Antioxidants

15 pages, 840 KiB

Open AccessReview

Therapeutic Potential of Polyphenols in Amyotrophic Lateral Sclerosis and Frontotemporal Dementia

by Valentina Novak, Boris Rogelj and Vera Župunski

Antioxidants 2021, 10(8), 1328; https://doi.org/10.3390/antiox10081328 - 23 Aug 2021

Cited by 27 | Viewed by 5289

Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are severe neurodegenerative disorders that belong to a common disease spectrum. The molecular and cellular aetiology of the spectrum is a highly complex encompassing dysfunction in many processes, including mitochondrial dysfunction and oxidative stress. There [...] Read more.

Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are severe neurodegenerative disorders that belong to a common disease spectrum. The molecular and cellular aetiology of the spectrum is a highly complex encompassing dysfunction in many processes, including mitochondrial dysfunction and oxidative stress. There is a paucity of treatment options aside from therapies with subtle effects on the post diagnostic lifespan and symptom management. This presents great interest and necessity for the discovery and development of new compounds and therapies with beneficial effects on the disease. Polyphenols are secondary metabolites found in plant-based foods and are well known for their antioxidant activity. Recent research suggests that they also have a diverse array of neuroprotective functions that could lead to better treatments for neurodegenerative diseases. We present an overview of the effects of various polyphenols in cell line and animal models of ALS/FTD. Furthermore, possible mechanisms behind actions of the most researched compounds (resveratrol, curcumin and green tea catechins) are discussed. Full article

(This article belongs to the Special Issue Dietary Polyphenols and Neuroprotection)

► Show Figures

Figure 1

15 pages, 2133 KiB

Open AccessArticle

Enzymatic Production of 3-OH Phlorizin, a Possible Bioactive Polyphenol from Apples, by Bacillus megaterium CYP102A1 via Regioselective Hydroxylation

by Ngoc Anh Nguyen, Ngoc Tan Cao, Thi Huong Ha Nguyen, Jung-Hwan Ji, Gun Su Cha, Hyung-Sik Kang and Chul-Ho Yun

Antioxidants 2021, 10(8), 1327; https://doi.org/10.3390/antiox10081327 - 23 Aug 2021

Cited by 12 | Viewed by 3579

Abstract

Phlorizin is the most abundant glucoside of phloretin from the apple tree and its products. Phlorizin and its aglycone phloretin are currently considered health-beneficial polyphenols from apples useful in treating hyperglycemia and obesity. Recently, we showed that phloretin could be regioselectively hydroxylated to [...] Read more.

Phlorizin is the most abundant glucoside of phloretin from the apple tree and its products. Phlorizin and its aglycone phloretin are currently considered health-beneficial polyphenols from apples useful in treating hyperglycemia and obesity. Recently, we showed that phloretin could be regioselectively hydroxylated to make 3-OH phloretin by Bacillus megaterium CYP102A1 and human P450 enzymes. The 3-OH phloretin has a potent inhibitory effect on differentiating 3T3-L1 preadipocytes into adipocytes and lipid accumulation. The glucoside of 3-OH phloretin would be a promising agent with increased bioavailability and water solubility compared with its aglycone. However, procedures to make 3-OH phlorizin, a glucoside of 3-OH phloretin, using chemical methods, are not currently available. Here, a biocatalytic strategy for the efficient synthesis of a possibly valuable hydroxylated product, 3-OH phlorizin, was developed via CYP102A1-catalyzed regioselective hydroxylation. The production of 3-OH phlorizin by CYP102A1 was confirmed by HPLC and LC–MS spectroscopy in addition to enzymatic removal of its glucose moiety for comparison to 3-OH phloretin. Taken together, in this study, we found a panel of mutants from B. megaterium CYP102A1 could catalyze regioselective hydroxylation of phlorizin to produce 3-OH phlorizin, a catechol product. Full article

(This article belongs to the Section Extraction and Industrial Applications of Antioxidants)

► Show Figures

Graphical abstract

17 pages, 883 KiB

Open AccessArticle

Effects of a Nanoencapsulated Moringa Leaf Ethanolic Extract on the Physiology, Metabolism and Reproductive Performance of Rabbit Does during Summer

by Nagwa I. El-Desoky, Nesrein M. Hashem, Antonio Gonzalez-Bulnes, Ahmed G. Elkomy and Zahraa R. Abo-Elezz

Antioxidants 2021, 10(8), 1326; https://doi.org/10.3390/antiox10081326 - 23 Aug 2021

Cited by 22 | Viewed by 3555

Abstract

This study investigated the effect of Moringa leaf ethanolic extract (MLEE) on heat-tolerance variables and the reproductive performance of rabbit does bred under hot climate conditions. Additionally, the effect of nanoencapsulation technology on the biological efficiency of MLEE was considered. A total of [...] Read more.

This study investigated the effect of Moringa leaf ethanolic extract (MLEE) on heat-tolerance variables and the reproductive performance of rabbit does bred under hot climate conditions. Additionally, the effect of nanoencapsulation technology on the biological efficiency of MLEE was considered. A total of 56 rabbit does were randomly divided into four experimental groups and treated with 50 mg/kg body weight (BW) nonencapsulated MLEE, 25 or 10 mg/kg BW nanoencapsulated MLEE, or not treated (Control, C). The treatments continued for 50 days, including mating and pregnancy times. Physiological and hematochemical variables, hormonal profiles, and reproductive performance (kindling rate and litter characteristics) were determined. The active components of MLEE were identified. The results indicated that MLEE has 30 active components. All MLEE-based treatments reduced heat-stress-related indicators, such as rectal temperatures, respiratory rates and heart rate; improved hematochemical attributes, redox status, and hormones (progesterone and prolactin); and increased the total litter size, the kindling rate, litter size at birth and litter weight at birth. Adding MLEE can alleviate the negative impacts of heat stress by improving metabolism, redox status, and hormonal balance during pregnancy. These effects were seen whether MLLE was in free or encapsulated forms. However, the use of nanoencapsulated MLEE allowed 80% reduction (10 mg/kg BW) in the optimal dose (50 mg/kg BW) without affecting the efficiency of the treatment. These results support the importance of nanoencapsulation technology in improving the bioavailability of active components when they are orally administered. Full article

(This article belongs to the Special Issue The Potential of Dietary Antioxidants)

► Show Figures

Figure 1

25 pages, 728 KiB

Open AccessReview

Role of Coenzyme Q₁₀ in Health and Disease: An Update on the Last 10 Years (2010–2020)

by Ilenia Cirilli, Elisabetta Damiani, Phiwayinkosi Vusi Dludla, Iain Hargreaves, Fabio Marcheggiani, Lauren Elizabeth Millichap, Patrick Orlando, Sonia Silvestri and Luca Tiano

Antioxidants 2021, 10(8), 1325; https://doi.org/10.3390/antiox10081325 - 23 Aug 2021

Cited by 59 | Viewed by 15499

Abstract

The present review focuses on preclinical and clinical studies conducted in the last decade that contribute to increasing knowledge on Coenzyme Q₁₀’s role in health and disease. Classical antioxidant and bioenergetic functions of the coenzyme have been taken into consideration, as [...] Read more.

The present review focuses on preclinical and clinical studies conducted in the last decade that contribute to increasing knowledge on Coenzyme Q₁₀’s role in health and disease. Classical antioxidant and bioenergetic functions of the coenzyme have been taken into consideration, as well as novel mechanisms of action involving the redox-regulated activation of molecular pathways associated with anti-inflammatory activities. Cardiovascular research and fertility remain major fields of application of Coenzyme Q₁₀, although novel applications, in particular in relation to topical application, are gaining considerable interest. In this respect, bioavailability represents a major challenge and the innovation in formulation aspects is gaining critical importance. Full article

(This article belongs to the Special Issue Health Effects of Coenzyme Q10)

► Show Figures

Figure 1

16 pages, 4083 KiB

Open AccessArticle

5-Hydroxymaltol Derived from Beetroot Juice through Lactobacillus Fermentation Suppresses Inflammatory Effect and Oxidant Stress via Regulating NF-kB, MAPKs Pathway and NRF2/HO-1 Expression

by Su-Lim Kim, Hack Sun Choi, Yu-Chan Ko, Bong-Sik Yun and Dong-Sun Lee

Antioxidants 2021, 10(8), 1324; https://doi.org/10.3390/antiox10081324 - 23 Aug 2021

Cited by 17 | Viewed by 3753

Abstract

Inflammation is the first response of the immune system against bacterial pathogens. This study isolated and examined an antioxidant derived from Lactobacillus fermentation products using cultured media with 1% beet powder. The antioxidant activity of the beet culture media was significantly high. Antioxidant [...] Read more.

Inflammation is the first response of the immune system against bacterial pathogens. This study isolated and examined an antioxidant derived from Lactobacillus fermentation products using cultured media with 1% beet powder. The antioxidant activity of the beet culture media was significantly high. Antioxidant activity-guided purification and repeated sample isolation yielded an isolated compound, which was identified as 5-hydoxymaltol using nuclear magnetic resonance spectrometry. We examined the mechanism of its protective effect on lipopolysaccharide (LPS)-induced inflammation of macrophages. 5-Hydroxymaltol suppressed nitric oxide (NO) production in LPS-stimulated RAW 264.7 cells. It also suppressed tumor necrosis factor α (TNF-α), interleukin (IL)-1β, and inducible nitric oxide synthase (iNOS) in the messenger RNA and protein levels in LPS-treated RAW 264.7 cells. Moreover, it suppressed LPS-induced nuclear translocation of NF-κB (p65) and mitogen-activated protein kinase activation. Furthermore, 5-hydroxymaltol reduced LPS-induced reactive oxygen species (ROS) production as well as increased nuclear factor erythroid 2–related factor 2 and heme oxygenase 1 expression. Overall, this study found that 5-hydroxymaltol has anti-inflammatory activities in LPS-stimulated RAW 264.7 macrophage cells based on its inhibition of pro-inflammatory cytokine production depending on the nuclear factor κB signaling pathway, inhibition of LPS-induced reactive oxygen species production, inhibition of LPS-induced mitogen-activated protein kinase induction, and induction of the nuclear factor erythroid 2–related factor 2/heme oxygenase 1 signaling pathway. Our data showed that 5-hydroxymaltol may be an effective compound for treating inflammation-mediated diseases. Full article

(This article belongs to the Special Issue Antioxidants and Bioactive Compounds in Fermented Foods)

► Show Figures

Graphical abstract

14 pages, 1136 KiB

Open AccessArticle

Association of Particulate Matter from Cooking Oil Fumes with Heart Rate Variability and Oxidative Stress

by Chang-Chuan Chan, Lian-Yu Lin, Ching-Huang Lai, Kai-Jen Chuang, Ming-Tsang Wu and Chih-Hong Pan

Antioxidants 2021, 10(8), 1323; https://doi.org/10.3390/antiox10081323 - 23 Aug 2021

Cited by 8 | Viewed by 2778

Abstract

Many studies have reported various cardiovascular autonomic responses to ambient particulate matter (PM) pollution, but few have reported such responses to occupational PM exposures. Even fewer have demonstrated a relationship between PM pollution and oxidative stress in humans. This panel study evaluates the [...] Read more.

Many studies have reported various cardiovascular autonomic responses to ambient particulate matter (PM) pollution, but few have reported such responses to occupational PM exposures. Even fewer have demonstrated a relationship between PM pollution and oxidative stress in humans. This panel study evaluates the association between occupational exposure to PM in cooking oil fumes (COFs), and changes in both heart rate variability (HRV) and oxidative stress responses in 54 male Chinese cooks. Linear mixed-effects regression models were adopted to estimate the strength of the association between PM and HRV. Participants’ pre- and post-workshift urine samples were analyzed for 8-hydroxy-2′-deoxyguanosine (8-OHdG) and malondialdehyde (MDA). Exposure to PM in COFs from 15 min to 2 h were associated with a decrease in HRV and an increase in heart rate among cooks. The urinary 8-OHdG levels of cooks were significantly elevated after workshift exposure to COFs. The levels of PM_2.5, PM_1.0, and particulate benzo(a)pyrene in COFs were all positively correlated with cross-workshift urinary 8-OHdG levels. Furthermore, the levels of benzo(a)pyrene in COFs were positively correlated with cross-workshift urinary MDA levels. The effects of COFs on HRV were independent of cross-workshift urinary 8-OHdG levels. Exposure to COFs leads to disturbed autonomic function and an increased risk of oxidative DNA injury among cooks in Chinese restaurants. Full article

(This article belongs to the Special Issue Oxidative/Nitrosative Stress-Related Mechanisms and Antioxidant Therapy in Cardiovascular Diseases)

► Show Figures

Figure 1

18 pages, 6608 KiB

Open AccessArticle

Effects of pH and Temperature on Water under Pressurized Conditions in the Extraction of Nutraceuticals from Chaga (Inonotus obliquus) Mushroom

by Ibrahim M. Abu-Reidah, Amber L. Critch, Charles F. Manful, Amanda Rajakaruna, Natalia P. Vidal, Thu H. Pham, Mumtaz Cheema and Raymond Thomas

Antioxidants 2021, 10(8), 1322; https://doi.org/10.3390/antiox10081322 - 23 Aug 2021

Cited by 21 | Viewed by 5611

Abstract

Currently, there is increased interest in finding appropriate food-grade green extraction systems capable of extracting these bioactive compounds from dietary mushrooms for applications in various food, pharmacological, or nutraceutical formulations. Herein, we evaluated a modified Swiss water process (SWP) method using alkaline and [...] Read more.

Currently, there is increased interest in finding appropriate food-grade green extraction systems capable of extracting these bioactive compounds from dietary mushrooms for applications in various food, pharmacological, or nutraceutical formulations. Herein, we evaluated a modified Swiss water process (SWP) method using alkaline and acidic pH at low and high temperature under pressurized conditions as a suitable green food grade solvent to obtained extracts enriched with myco-nutrients (dietary phenolics, total antioxidants (TAA), vitamins, and minerals) from Chaga. Ultra-high performance liquid chromatography coupled to high resolution accurate mass tandem mass spectrometry (UHPLC-HRAMS-MS/MS) was used to assess the phenolic compounds and vitamin levels in the extracts, while inductively coupled plasma mass spectrometry (ICP-MS) was used to determine the mineral contents. Over 20 phenolic compounds were quantitatively evaluated in the extracts and the highest total phenolic content (TPC) and total antioxidant activity (TAA) was observed at pH 11.5 at 100 °C. The most abundant phenolic compounds present in Chaga extracts included phenolic acids such as protocatechuic acid 4-glucoside (0.7–1.08 µg/mL), syringic acid (0.62–1.18 µg/mL), and myricetin (0.68–1.3 µg/mL). Vitamins are being reported for the first time in Chaga. Not only, a strong correlation was found for TPC with TAA (r-0.8, <0.0001), but also, with individual phenolics (i.e., Salicylic acid), lipophilic antioxidant activity (LAA), and total antioxidant minerals (TAM). pH 2.5 at 100 °C treatment shows superior effects in extracting the B vitamins whereas pH 2.5 at 60 and 100 °C treatments were outstanding for extraction of total fat-soluble vitamins. Vitamin E content was the highest for the fat-soluble vitamins in the Chaga extract under acidic pH (2.5) and high temp. (100 °C) and ranges between 50 to 175 µg/100 g Chaga. Antioxidant minerals ranged from 85.94 µg/g (pH7 at 100 °C) to 113.86 µg/g DW (pH2.5 at 100 °C). High temperature 100 °C and a pH of 2.5 or 9.5. The treatment of pH 11.5 at 100 °C was the most useful for recovering phenolics and antioxidants from Chaga including several phenolic compounds reported for the first time in Chaga. SWP is being proposed herein for the first time as a novel, green food-grade solvent system for the extraction of myco-nutrients from Chaga and have potential applications as a suitable approach to extract nutrients from other matrices. Chaga extracts enriched with bioactive myconutrients and antioxidants may be suitable for further use or applications in the food and nutraceutical industries. Full article

(This article belongs to the Special Issue From the Green Extraction of Food Waste and By-Products to the Structure-Activity Relationships of Natural Antioxidants)

► Show Figures

Figure 1

16 pages, 2856 KiB

Open AccessArticle

Long-Term Treatment of Cuban Policosanol Attenuates Abnormal Oxidative Stress and Inflammatory Response via Amyloid Plaques Reduction in 5xFAD Mice

by Jin-Ho Kim, Dong-Kyun Lim, Yoo-Hun Suh and Keun-A Chang

Antioxidants 2021, 10(8), 1321; https://doi.org/10.3390/antiox10081321 - 23 Aug 2021

Cited by 11 | Viewed by 3937

Abstract

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder resulting in cognitive decline or dementia, the number of patients with AD is continuously increasing. Although a lot of great progress has been made in research and development of AD therapeutics, there is no fundamental [...] Read more.

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder resulting in cognitive decline or dementia, the number of patients with AD is continuously increasing. Although a lot of great progress has been made in research and development of AD therapeutics, there is no fundamental cure for this disease yet. This study demonstrated the memory-improving effects of Cuban policosanol (PCO) in 5xFAD mice, which is an animal model of AD. Following 4-months of treatment with PCO in 5xFAD mice, we found that the number of amyloid plaques decreased in the brain compared to the vehicle-treated 5xFAD mice. Long-term PCO treatment in 5xFAD mice resulted in the reduction of gliosis and abnormal inflammatory cytokines level (interleukin [IL]-1β, IL-6, and tumor necrosis factor [TNF]-α) in the cortex and hippocampus. Levels of lipid peroxide (4-hydroxynonenal [4-HNE]) and superoxide dismutase (SOD1 and SOD2) levels were also recoverd in the brains of PCO-treated 5xFAD mice. Notably, PCO administration reduced memory deficits in the passive avoidance test, as well as synaptic loss (PSD-95, synaptophysin) in 5xFAD mice. Collectively, we identified the potential effects of PCO as a useful supplement to delay or prevent AD progression by inhibiting the formation of Aβ plaques in the brain. Full article

► Show Figures

Figure 1

20 pages, 3509 KiB

Open AccessArticle

Silicon Improves the Redox Homeostasis to Alleviate Glyphosate Toxicity in Tomato Plants—Are Nanomaterials Relevant?

by Cristiano Soares, Pedro Nadais, Bruno Sousa, Edgar Pinto, Isabel M. P. L. V. O. Ferreira, Ruth Pereira and Fernanda Fidalgo

Antioxidants 2021, 10(8), 1320; https://doi.org/10.3390/antiox10081320 - 23 Aug 2021

Cited by 14 | Viewed by 3818

Abstract

Given the widespread use of glyphosate (GLY), this agrochemical is becoming a source of contamination in agricultural soils, affecting non-target plants. Therefore, sustainable strategies to increase crop tolerance to GLY are needed. From this perspective and recalling silicon (Si)’s role in alleviating different [...] Read more.

Given the widespread use of glyphosate (GLY), this agrochemical is becoming a source of contamination in agricultural soils, affecting non-target plants. Therefore, sustainable strategies to increase crop tolerance to GLY are needed. From this perspective and recalling silicon (Si)’s role in alleviating different abiotic stresses, the main goal of this study was to assess if the foliar application of Si, either as bulk or nano forms, is capable of enhancing Solanum lycopersicum L. tolerance to GLY (10 mg kg⁻¹). After 28 day(s), GLY-treated plants exhibited growth-related disorders in both shoots and roots, accompanied by an overproduction of superoxide anion (O₂^•−) and malondialdehyde (MDA) in shoots. Although plants solely exposed to GLY have activated non-enzymatic antioxidant mechanisms (proline, ascorbate and glutathione), a generalized inhibition of the antioxidant enzymes was found, suggesting the occurrence of great redox disturbances. In response to Si or nano-SiO₂ co-application, most of GLY phytotoxic effects on growth were prevented, accompanied with a better ROS removal, especially by an upregulation of the main antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX). Overall, results pointed towards the potential of both sources of Si to reduce GLY-induced oxidative stress, without major differences between their efficacy. Full article

(This article belongs to the Special Issue Antioxidant Mechanisms in Plants)

► Show Figures

Figure 1

15 pages, 2097 KiB

Open AccessArticle

Bilberry (Vaccinium myrtillus L.) Powder Has Anticarcinogenic Effects on Oral Carcinoma In Vitro and In Vivo

by Matti Mauramo, Tuulia Onali, Wafa Wahbi, Jenni Vasara, Anniina Lampinen, Elina Mauramo, Anne Kivimäki, Stefan Martens, Hely Häggman, Meeri Sutinen and Tuula Salo

Antioxidants 2021, 10(8), 1319; https://doi.org/10.3390/antiox10081319 - 22 Aug 2021

Cited by 13 | Viewed by 4151

Abstract

Previous studies indicate that bilberry with high amounts of phenolic compounds can inhibit carcinogenic processes of colorectal cancer in vitro and in vivo. However, no studies have focused on the effects of bilberry on oral cancer. In this study, we aimed to examine [...] Read more.

Previous studies indicate that bilberry with high amounts of phenolic compounds can inhibit carcinogenic processes of colorectal cancer in vitro and in vivo. However, no studies have focused on the effects of bilberry on oral cancer. In this study, we aimed to examine the effects of bilberry powder on oral squamous cell carcinoma (OSCC) cells using both in vitro and in vivo assays. The effects of 0, 1, 10, and 25 mg/mL of whole bilberry powder on the viability, proliferation, migration, and invasion of OSCC (HSC-3) cells were examined and compared with 0.01 mg/mL of cetuximab. Two oral keratinocyte cell lines served as controls. Tumor area was analyzed in zebrafish microinjected with HSC-3 cells and treated with 2.5, 10, or 25 µg/mL of bilberry powder. Metastases in the head or tail areas were counted. Bilberry powder inhibited the viability, proliferation, migration, and invasion of HSC-3 cells (p < 0.05), which was more pronounced with higher concentrations. Cetuximab had no effect on HSC-3 cell migration or invasion. Compared to controls, the tumor area in zebrafish treated with bilberry powder (10 and 25 µg/mL) was reduced significantly (p = 0.038 and p = 0.021, respectively), but the number of fish with metastases did not differ between groups. Based on our in vitro and in vivo experiments, we conclude that whole bilberry powder has anti-tumor effects on OSCC cells. Full article

► Show Figures

Figure 1

11 pages, 287 KiB

Open AccessArticle

Dietary Blueberry and Soluble Fiber Improve Serum Antioxidant and Adipokine Biomarkers and Lipid Peroxidation in Pregnant Women with Obesity and at Risk for Gestational Diabetes

by Arpita Basu, Jeannette Crew, Jeffrey L. Ebersole, Jefferson W. Kinney, Arnold M. Salazar, Petar Planinic and James M. Alexander

Antioxidants 2021, 10(8), 1318; https://doi.org/10.3390/antiox10081318 - 22 Aug 2021

Cited by 18 | Viewed by 3673

Abstract

Pregnancies affected by obesity are at high risk for developing metabolic complications with oxidative stress and adipocyte dysfunction contributing to the underlying pathologies. Few studies have examined the role of dietary interventions, especially those involving antioxidants including polyphenolic flavonoids found in fruits and [...] Read more.

Pregnancies affected by obesity are at high risk for developing metabolic complications with oxidative stress and adipocyte dysfunction contributing to the underlying pathologies. Few studies have examined the role of dietary interventions, especially those involving antioxidants including polyphenolic flavonoids found in fruits and vegetables on these pathologies in high-risk pregnant women. We conducted an 18 gestation-week randomized controlled trial to examine the effects of a dietary intervention comprising of whole blueberries and soluble fiber vs. control (standard prenatal care) on biomarkers of oxidative stress/antioxidant status and adipocyte and hormonal functions in pregnant women with obesity (n = 34). Serum samples were collected at baseline (<20 gestation weeks) and at the end of the study period (32–26 gestation weeks). Study findings showed maternal serum glutathione and antioxidant capacity to be significantly increased, and malondialdehyde to be decreased in the dietary intervention vs. control group (all p < 0.05). Among the adipokine biomarkers, serum plasminogen activator inhibitor-1 and visfatin, as biomarkers of adipocyte dysfunction and insulin resistance, were also decreased following dietary intervention (all p < 0.05). These findings support the need for supplementing maternal diets with berries and fiber to improve oxidative stress and risks of metabolic complications during pregnancy. Full article

(This article belongs to the Special Issue Antioxidants, Oxidative Stress and Non-communicable Diseases)

19 pages, 2375 KiB

Open AccessArticle

Ultrasound-Assisted Extraction Optimization of Proanthocyanidins from Kiwi (Actinidia chinensis) Leaves and Evaluation of Its Antioxidant Activity

by Ji-Min Lv, Mostafa Gouda, Yan-Yun Zhu, Xing-Qian Ye and Jian-Chu Chen

Antioxidants 2021, 10(8), 1317; https://doi.org/10.3390/antiox10081317 - 21 Aug 2021

Cited by 30 | Viewed by 4600

Abstract

Using ultrasound (US) in proanthocyanidin (PA) extraction has become one of the important emerging technologies. It could be the next generation for studying the US mechnophore impact on the bioactive compound’s functionality. The objective of this study was to demonstrate the potential of [...] Read more.

Using ultrasound (US) in proanthocyanidin (PA) extraction has become one of the important emerging technologies. It could be the next generation for studying the US mechnophore impact on the bioactive compound’s functionality. The objective of this study was to demonstrate the potential of US treatment on PAs extracted from kiwifruit (Actinidia chinensis) leaves, and to provide a comprehensive chemical composition and bioactivity relationship of the purified kiwifruit leaves PAs (PKLPs). Several methods like single-factor experiments and response surface methodology (RSM) for the four affected factors on US extraction efficiency were constructed. HPLC-QTOF-MS/MS, cytotoxicity analysis, and antioxidant activity were also demonstrated. In the results, the modeling of PA affected factors showed that 40% US-amplitude, 30 mL/g dry weight (DW) solvent to solid ration (S/S), and 70 °C for 15 min were the optimum conditions for the extraction of PAs. Furthermore, PKLPs exhibited significant radical scavenging and cellular antioxidant activity (p < 0.05). In conclusion, this study’s novelty comes from the broad prospects of using US in PKLP green extraction that could play an important role in maximizing this phytochemical functionality in drug discovery and food science fields. Full article

(This article belongs to the Special Issue New Insights into Phytochemical Antioxidants in Food)

► Show Figures

Figure 1

18 pages, 1548 KiB

Open AccessReview

The Alteration of Chloride Homeostasis/GABAergic Signaling in Brain Disorders: Could Oxidative Stress Play a Role?

by Provvidenza M. Abruzzo, Cristina Panisi and Marina Marini

Antioxidants 2021, 10(8), 1316; https://doi.org/10.3390/antiox10081316 - 21 Aug 2021

Cited by 14 | Viewed by 3997

Abstract

In neuronal precursors and immature neurons, the depolarizing (excitatory) effect of γ-Aminobutyric acid (GABA) signaling is associated with elevated [Cl⁻]_i; as brain cells mature, a developmental switch occurs, leading to the decrease of [Cl⁻]_i and to [...] Read more.

In neuronal precursors and immature neurons, the depolarizing (excitatory) effect of γ-Aminobutyric acid (GABA) signaling is associated with elevated [Cl⁻]_i; as brain cells mature, a developmental switch occurs, leading to the decrease of [Cl⁻]_i and to the hyperpolarizing (inhibitory) effect of GABAergic signaling. [Cl⁻]_i is controlled by two chloride co-transporters: NKCC1, which causes Cl⁻ to accumulate into the cells, and KCC2, which extrudes it. The ontogenetic upregulation of the latter determines the above-outlined switch; however, many other factors contribute to the correct [Cl⁻]_i in mature neurons. The dysregulation of chloride homeostasis is involved in seizure generation and has been associated with schizophrenia, Down’s Syndrome, Autism Spectrum Disorder, and other neurodevelopmental disorders. Recently, much effort has been put into developing new drugs intended to inhibit NKCC1 activity, while no attention has been paid to the origin of [Cl⁻]_i dysregulation. Our study examines the pathophysiology of Cl⁻ homeostasis and focuses on the impact of oxidative stress (OS) and inflammation on the activity of Cl⁻ co-transporters, highlighting the relevance of OS in numerous brain abnormalities and diseases. This hypothesis supports the importance of primary prevention during pregnancy. It also integrates the therapeutic framework addressed to restore normal GABAergic signaling by counteracting the alteration in chloride homeostasis in central nervous system (CNS) cells, aiming at limiting the use of drugs that potentially pose a health risk. Full article

(This article belongs to the Special Issue Oxidative Stress and Neuroinflammation in Neurological and Neurodegenerative Disorders)

► Show Figures

Figure 1

24 pages, 4495 KiB

Open AccessReview

Mechanistic Basis and Clinical Evidence for the Applications of Nicotinamide (Niacinamide) to Control Skin Aging and Pigmentation

by Yong Chool Boo

Antioxidants 2021, 10(8), 1315; https://doi.org/10.3390/antiox10081315 - 21 Aug 2021

Cited by 86 | Viewed by 45452

Abstract

Vitamin B3 (nicotinic acid, niacin) deficiency causes the systemic disease pellagra, which leads to dermatitis, diarrhea, dementia, and possibly death depending on its severity and duration. Vitamin B3 is used in the synthesis of the NAD⁺ family of coenzymes, contributing to cellular [...] Read more.

Vitamin B3 (nicotinic acid, niacin) deficiency causes the systemic disease pellagra, which leads to dermatitis, diarrhea, dementia, and possibly death depending on its severity and duration. Vitamin B3 is used in the synthesis of the NAD⁺ family of coenzymes, contributing to cellular energy metabolism and defense systems. Although nicotinamide (niacinamide) is primarily used as a nutritional supplement for vitamin B3, its pharmaceutical and cosmeceutical uses have been extensively explored. In this review, we discuss the biological activities and cosmeceutical properties of nicotinamide in consideration of its metabolic pathways. Supplementation of nicotinamide restores cellular NAD⁺ pool and mitochondrial energetics, attenuates oxidative stress and inflammatory response, enhances extracellular matrix and skin barrier, and inhibits the pigmentation process in the skin. Topical treatment of nicotinamide, alone or in combination with other active ingredients, reduces the progression of skin aging and hyperpigmentation in clinical trials. Topically applied nicotinamide is well tolerated by the skin. Currently, there is no convincing evidence that nicotinamide has specific molecular targets for controlling skin aging and pigmentation. This substance is presumed to contribute to maintaining skin homeostasis by regulating the redox status of cells along with various metabolites produced from it. Thus, it is suggested that nicotinamide will be useful as a cosmeceutical ingredient to attenuate skin aging and hyperpigmentation, especially in the elderly or patients with reduced NAD⁺ pool in the skin due to internal or external stressors. Full article

(This article belongs to the Special Issue Antioxidants in Age-Related Diseases and Anti-Aging Strategies)

► Show Figures

Figure 1

16 pages, 2575 KiB

Open AccessArticle

Curcumin Suppresses the Lipid Accumulation and Oxidative Stress Induced by Benzo[a]pyrene Toxicity in HepG2 Cells

by Seung-Cheol Lee, Seung-Cheol Jee, Min Kim, Soee Kim, Min Kyoung Shin, Yunkyung Kim and Jung-Suk Sung

Antioxidants 2021, 10(8), 1314; https://doi.org/10.3390/antiox10081314 - 20 Aug 2021

Cited by 19 | Viewed by 4842

Abstract

Benzo[a]pyrene (B[a]P) is a potentially hepatotoxic group-1 carcinogen taken up by the body through ingestion of daily foods. B[a]P is widely known to cause DNA and protein damages, which are closely related to cell transformation. Accordingly, studies on natural bioactive compounds that attenuate [...] Read more.

Benzo[a]pyrene (B[a]P) is a potentially hepatotoxic group-1 carcinogen taken up by the body through ingestion of daily foods. B[a]P is widely known to cause DNA and protein damages, which are closely related to cell transformation. Accordingly, studies on natural bioactive compounds that attenuate such chemical-induced toxicities have significant impacts on public health. This study aimed to uncover the mechanism of curcumin, the major curcuminoid in turmeric (Curcuma longa), in modulating the lipid accumulation and oxidative stress mediated by B[a]P cytotoxicity in HepG2 cells. Curcumin treatment reduced the B[a]P-induced lipid accumulation and reactive oxygen spicies (ROS) upregulation and recovered the cell viability. Cytochrome P450 family 1 subfamily A polypeptide 1 (CYP1A1) and Cytochrome P450 subfamily B polypeptide 1 (CYP1B1) downregulation resulting from decreased aryl hydrocarbon receptor (AhR) translocation into nuclei attenuated the effects of B[a]P-induced lipid accumulation and repressed cell viability, respectively. Moreover, the curcumin-induced reduction in ROS generation decreased the nuclear translocation of Nuclear factor erythroid-2-related factor 2 (Nrf2) and the expression of phase-II detoxifying enzymes. These results indicate that curcumin suppresses B[a]P-induced lipid accumulation and ROS generation which can potentially induce nonalcoholic fatty liver disease (NAFLD) and can shed a light on the detoxifying effect of curcumin. Full article

(This article belongs to the Special Issue Antioxidant Agents for the Prevention and Therapy of Oxidative Stress in Hepatic Diseases)

► Show Figures

Figure 1

10 pages, 298 KiB

Open AccessArticle

Effects of Fusarium Mycotoxin Exposure on Lipid Peroxidation and Glutathione Redox System in the Liver of Laying Hens

by Szabina Kulcsár, Benjámin Kövesi, Krisztián Balogh, Erika Zándoki, Zsolt Ancsin, Balláné Erdélyi Márta and Miklós Mézes

Antioxidants 2021, 10(8), 1313; https://doi.org/10.3390/antiox10081313 - 20 Aug 2021

Cited by 13 | Viewed by 2657

Abstract

It has been proven by several studies that Fusarium mycotoxins induce oxidative stress in animals, consequently inducing lipid peroxidation, which the glutathione system can neutralize. A short-term (3-day) in vivo feeding trial was performed with laying hens using a double dose of the [...] Read more.

It has been proven by several studies that Fusarium mycotoxins induce oxidative stress in animals, consequently inducing lipid peroxidation, which the glutathione system can neutralize. A short-term (3-day) in vivo feeding trial was performed with laying hens using a double dose of the EU recommendation for mycotoxin contamination (T-2 toxin 0.5 mg/kg feed; deoxynivalenol (DON) 10 mg/kg feed; fumonisin B₁ (FB1) 40 mg/kg feed). Some lipid peroxidation and glutathione redox system parameters and gene expression levels were measured in the liver. The results show that FB1 significantly decreased the reduced glutathione (GSH) content and the activity of glutathione peroxidase (GPx) compared to the control and the two other mycotoxin-treated groups on day 3. Lipid peroxidation was affected by all three mycotoxins. Significantly lower values were observed in the case of conjugated dienes for all of the three mycotoxins and malondialdehyde concentration as an effect of DON on day 3. T-2 toxin and DON upregulated the expression of the GPX4 gene. The results show that Fusarium mycotoxins had different effects at the end of the trial. The FB1 exposure caused a decrease in the glutathione redox markers, while DON decreased the formation of malondialdehyde. The results suggest that the Fusarium mycotoxins investigated individually differently activated the antioxidant defense and caused low-level oxidative stress at the dose applied. Full article

(This article belongs to the Special Issue Antioxidant Defences and Redox Homeostasis in Animals)

37 pages, 2859 KiB

Open AccessArticle

Impact of Drying Processes on the Nutritional Composition, Volatile Profile, Phytochemical Content and Bioactivity of Salicornia ramosissima J. Woods

by Sheila C. Oliveira-Alves, Fábio Andrade, Inês Prazeres, Andreia B. Silva, Jorge Capelo, Bernardo Duarte, Isabel Caçador, Júlio Coelho, Ana Teresa Serra and Maria R. Bronze

Antioxidants 2021, 10(8), 1312; https://doi.org/10.3390/antiox10081312 - 20 Aug 2021

Cited by 32 | Viewed by 5592

Abstract

Salicornia ramosissima J. Woods is a halophyte plant recognized as a promising natural ingredient and will eventually be recognized a salt substitute (NaCl). However, its shelf-life and applicability in several food matrices requires the use of drying processes, which may have an impact [...] Read more.

Salicornia ramosissima J. Woods is a halophyte plant recognized as a promising natural ingredient and will eventually be recognized a salt substitute (NaCl). However, its shelf-life and applicability in several food matrices requires the use of drying processes, which may have an impact on its nutritional and functional value. The objective of this study was to evaluate the effect of oven and freeze-drying processes on the nutritional composition, volatile profile, phytochemical content, and bioactivity of S. ramosissima using several analytical tools (LC-DAD-ESI-MS/MS and SPME-GC-MS) and bioactivity assays (ORAC, HOSC, and ACE inhibition and antiproliferative effect on HT29 cells). Overall, results show that the drying process changes the chemical composition of the plant. When compared to freeze-drying, the oven-drying process had a lower impact on the nutritional composition but the phytochemical content and antioxidant capacity were significantly reduced. Despite this, oven-dried and freeze-dried samples demonstrated similar antiproliferative (17.56 mg/mL and 17.24 mg/mL, respectively) and antihypertensive (24.56 mg/mL and 18.96 mg/mL, respectively) activities. The volatile composition was also affected when comparing fresh and dried plants and between both drying processes: while for the freeze-dried sample, terpenes corresponded to 57% of the total peak area, a decrease to 17% was observed for the oven-dried sample. The oven-dried S. ramosissima was selected to formulate a ketchup and the product formulated with 2.2% (w/w) of the oven-dried plant showed a good consumer acceptance score. These findings support the use of dried S. ramosissima as a promising functional ingredient that can eventually replace the use of salt. Full article

(This article belongs to the Special Issue Impact of Processing on Antioxidant Rich Foods)

► Show Figures

Figure 1

17 pages, 2986 KiB

Open AccessArticle

Expression of Endothelial NOX5 Alters the Integrity of the Blood-Brain Barrier and Causes Loss of Memory in Aging Mice

by Adriana Cortés, Maite Solas, Álvaro Pejenaute, Miguel A. Abellanas, Marcos Garcia-Lacarte, Maria S. Aymerich, Javier Marqués, María J. Ramírez and Guillermo Zalba

Antioxidants 2021, 10(8), 1311; https://doi.org/10.3390/antiox10081311 - 20 Aug 2021

Cited by 16 | Viewed by 3005

Abstract

Blood-Brain barrier (BBB) disruption is a hallmark of central nervous system (CNS) dysfunction, and oxidative stress is one of the molecular mechanisms that may underlie this process. NADPH oxidases (NOX) are involved in oxidative stress-mediated vascular dysfunction and participate in the pathophysiology of [...] Read more.

Blood-Brain barrier (BBB) disruption is a hallmark of central nervous system (CNS) dysfunction, and oxidative stress is one of the molecular mechanisms that may underlie this process. NADPH oxidases (NOX) are involved in oxidative stress-mediated vascular dysfunction and participate in the pathophysiology of its target organs. The NADPH oxidase 5 (NOX5) isoform is absent in rodents, and although little is known about the role it may play in disrupting the BBB, it has recently been implicated in experimental stroke. Our aim was to investigate the role of NADPH oxidase 5 (NOX5) in promoting vascular alterations and to identify its impact on the cognitive status of aged mice. No differences were detected in the arterial blood pressure or body weight between knock-in mice expressing endothelial NOX5 and the control mice. The Morris water maze test showed memory impairments in the aged knock-in mice expressing NOX5 compared with their control littermates. For assessing the BBB integrity, we studied the protein expression of two tight junction (TJ) proteins: Zonula occludens-1 (ZO-1) and occludin. Compared to the control animals, Aged NOX5 mice exhibited reduced levels of both proteins, demonstrating an alteration of the BBB integrity. Our data indicate that vascular NOX5 may favor behavioral changes with aging through oxidative stress-mediated BBB breakdown. Full article

(This article belongs to the Special Issue Oxidative Stress in Cardiovascular Disease and Comorbidities)

► Show Figures

Figure 1

11 pages, 458 KiB

Open AccessReview

Involvement of microRNAs as a Response to Phototherapy and Photodynamic Therapy: A Literature Review

by Francesco Borgia, Paolo Custurone, Lucia Peterle, Giovanni Pioggia, Fabrizio Guarneri and Sebastiano Gangemi

Antioxidants 2021, 10(8), 1310; https://doi.org/10.3390/antiox10081310 - 20 Aug 2021

Cited by 4 | Viewed by 2348

Abstract

The current knowledge about the mechanisms of action of light-based treatments (chiefly photodynamic therapy and phototherapy) in skin diseases leans to the possible involvement of epigenetic and oxidative stress mechanisms. To better understand and exploit, to the fullest, these relatively safe and reproducible [...] Read more.

The current knowledge about the mechanisms of action of light-based treatments (chiefly photodynamic therapy and phototherapy) in skin diseases leans to the possible involvement of epigenetic and oxidative stress mechanisms. To better understand and exploit, to the fullest, these relatively safe and reproducible treatments, several studies have focused on miRNAs, small non-encoding RNAs (22–24 nucleotides), after light-based treatments. The current narrative review focused on 25 articles. A meta-analysis was not deemed appropriate. The results gather the most recurrent skin-related miRNAs up- or downregulated after light treatment. Five of these, miR-21, -29, -125, -145 and -155, are either the most consistently related to efficacy/resistance to treatment or identified as helpful diagnostic tools. A specific class of miRNAs (angioMIRs) requires further studies. Future treatments and imaging techniques could benefit greatly from the use of antagomirs as a possible co-adjuvant therapy along with light-based treatments. Full article

► Show Figures

Figure 1

13 pages, 3449 KiB

Open AccessArticle

Hypolipidemic Effects and Preliminary Mechanism of Chrysanthemum Flavonoids, Its Main Components Luteolin and Luteoloside in Hyperlipidemia Rats

by Jihan Sun, Zhaodan Wang, Lin Chen and Guiju Sun

Antioxidants 2021, 10(8), 1309; https://doi.org/10.3390/antiox10081309 - 20 Aug 2021

Cited by 54 | Viewed by 4547

Abstract

This study aimed to investigate the key constituents and preliminary mechanism for the hypolipidemic activity of chrysanthemum flavonoids. Hyperlipidemia (HPL) rats were divided into five groups: the model control group (MC); Chrysanthemum flavone intervention group (CF); luteolin intervention group; luteoloside intervention group and [...] Read more.

This study aimed to investigate the key constituents and preliminary mechanism for the hypolipidemic activity of chrysanthemum flavonoids. Hyperlipidemia (HPL) rats were divided into five groups: the model control group (MC); Chrysanthemum flavone intervention group (CF); luteolin intervention group; luteoloside intervention group and simvastatin intervention group. The body weight, organ coefficient, serum lipids, antioxidant activity, and lipid metabolism enzymes were detected. Hematoxylin and eosin (H&E) staining was used to observe the liver and adipose tissue. Chrysanthemum flavonoids, luteolin, and luteoloside can reduce the weight and levels of total cholesterol (TC), triglycerides (TG), and LDL-C, and increase the level of HDL-C in the blood and reduce liver steatosis. Indicators of liver function (AST, ALT, and ALP) improved. The antioxidant activity (GSH-Px, CAT, SOD) and enzymes associated with lipid catabolism (FAβO, CYP7A1, and HL) increased, while lipid peroxidation products (MDA) and enzymes associated with lipid synthesis (FAS, HMG-CoA, and DGAT) decreased. Chrysanthemum flavonoids had a better effect on the antioxidant level and lipid metabolism-related enzyme activity. There was no significant difference in the effects of the chrysanthemum flavonoids, luteolin, and Luteoloside on improving blood lipids and hepatic steatosis—mechanisms that may be related to antioxidant levels and regulating enzymes involved in the metabolism of fatty acids, cholesterol, and triglycerides in the liver. However, chrysanthemum flavonoids had a stronger antioxidant and lipid metabolism regulation ability, and the long-term effects may be better. Full article

► Show Figures

Graphical abstract

23 pages, 4084 KiB

Open AccessArticle

Hyperphosphatemia-Induced Oxidant/Antioxidant Imbalance Impairs Vascular Relaxation and Induces Inflammation and Fibrosis in Old Mice

by Ana Asenjo-Bueno, Elena Alcalde-Estévez, Mariam El Assar, Gemma Olmos, Patricia Plaza, Patricia Sosa, Patricia Martínez-Miguel, María Piedad Ruiz-Torres and Susana López-Ongil

Antioxidants 2021, 10(8), 1308; https://doi.org/10.3390/antiox10081308 - 19 Aug 2021

Cited by 15 | Viewed by 2872

Abstract

Aging impairs vascular function, but the mechanisms involved are unknown. The aim of this study was to analyze whether aging-related hyperphosphatemia is implied in this effect by elucidating the role of oxidative stress. C57BL6 mice that were aged 5 months (young) and 24 [...] Read more.

Aging impairs vascular function, but the mechanisms involved are unknown. The aim of this study was to analyze whether aging-related hyperphosphatemia is implied in this effect by elucidating the role of oxidative stress. C57BL6 mice that were aged 5 months (young) and 24 months (old), receiving a standard (0.6%) or low-phosphate (0.2%) diet, were used. Isolated mesenteric arteries from old mice showed diminished endothelium-dependent vascular relaxation by the down-regulation of NOS3 expression, increased inflammation and increased fibrosis in isolated aortas, compared to those isolated from young mice. In parallel, increased Nox4 expression and reduced Nrf2, Sod2-Mn and Gpx1 were found in the aortas from old mice, resulting in oxidant/antioxidant imbalance. The low-phosphate diet improved vascular function and oxidant/antioxidant balance in old mice. Mechanisms were analyzed in endothelial (EC) and vascular smooth muscle cells (SMCs) treated with the phosphate donor ß-glycerophosphate (BGP). In EC, BGP increased Nox4 expression and ROS production, which reduced NOS3 expression via NFκB. BGP also increased inflammation in EC. In SMC, BGP increased Collagen I and fibronectin expression by priming ROS production and NFκB activity. In conclusion, hyperphosphatemia reduced endothelium-dependent vascular relaxation and increased inflammation and vascular fibrosis through an impairment of oxidant/antioxidant balance in old mice. A low-phosphate diet achieved improvements in the vascular function in old mice. Full article

(This article belongs to the Special Issue Oxidative Stress in Aging and Associated Chronic Diseases)

► Show Figures

Figure 1

23 pages, 5884 KiB

Open AccessArticle

In Vitro and In Silico Toxicological Properties of Natural Antioxidant Therapeutic Agent Azima tetracantha. LAM

by Palanisamy Prakash, Nisha Kumari, Ekambaram Gayathiri, Kuppusamy Selvam, Manikavali Gurunadhan Ragunathan, Murugesan Chandrasekaran, Munirah Abdullah Al-Dosary, Ashraf Atef Hatamleh, Ashok Kumar Nadda and Manu Kumar

Antioxidants 2021, 10(8), 1307; https://doi.org/10.3390/antiox10081307 - 18 Aug 2021

Cited by 8 | Viewed by 4376

Abstract

Plant-derived antioxidants are a large group of natural products with the capacity to reduce radical-scavenging. Due to their potent therapeutic and preventive actions, these compounds receive a lot of attention from scientists, particularly pharmacologists. The pharmacological activities of the Azima tetracantha Lam. ( [...] Read more.

Plant-derived antioxidants are a large group of natural products with the capacity to reduce radical-scavenging. Due to their potent therapeutic and preventive actions, these compounds receive a lot of attention from scientists, particularly pharmacologists. The pharmacological activities of the Azima tetracantha Lam. (AT) plant, belonging to the Salvadoraceae family, reported here justifies its traditional use in treating several diseases or disorders. This study aims to look at the propensity of certain plant compounds found in natural AT plant extracts that might play a critical role as a secondary metabolite in cervical cancer treatment. There is a shortage of information on the plant’s phytochemical and biological characteristics. Methanol (MeOH) solvent extracts of the dried AT plant were screened phytochemically. Its aqueous extract was tested for antioxidant, antiseptic, anti-inflammatory, and anticancerous properties. Absorption Distribution Metabolism and Excretion (ADME/T), Docking, and HPLC were also performed. In clinical treatment, the plant shown no adverse effects. The antioxidant activity was evaluated and showed the highest concentration at 150 µg/mL (63.50%). MeOH leaf extract of AT exhibited the highest and best inhibitory activity against Staphylococcus aureus (15.3 mm/1000) and displayed a high antiseptic potential. At a 200 µg/mL concentration, MeOH leaves-extract inhibited red blood cells (RBC) hemolysis by 66.56 ± 0.40, compared with 62.33 ± 0.40 from the standard. Albumin’s ability to suppress protein denaturation ranged from 16.75 ± 0.65 to 62.35 ± 0.20 inhibitions in this test, providing even more support for its favorable anti-inflammatory properties. The ADME/T studies were considered for a potential cancer drug molecule, and one of our compounds from MeOH extract fills the ADME and toxicity parameters. The forms of compound 4 showed a strong hydrogen-bonding interaction with the vital amino acids (ASN923, THR410, LEU840TRY927, PHE921, and GLY922). A total of 90% of cell inhibition was observed when HeLa cell lines were treated with 300 µg/mL of compound 4 (7-acetyl-3a¹-methyl- 4,14-dioxo-1,2,3a,3a¹,4,5,5a,6,8a,9b,10,11,11a-tetradecahydro-2,5a epoxy5,6a (methanooxymethano)phenaleno[1′,9′:5,6,7]indeno[1,7a-b]oxiren-2-yl acetate). The polyphenol compounds demonstrated significant advances in anticancer drug properties, and it could lead to activation of cancer cell apoptosis. Full article

(This article belongs to the Special Issue Antioxidant and Biological Properties of Plant Extracts)

► Show Figures

Graphical abstract

13 pages, 718 KiB

Open AccessReview

Pathophysiological Association between Diabetes Mellitus and Endothelial Dysfunction

by Tatsuya Maruhashi and Yukihito Higashi

Antioxidants 2021, 10(8), 1306; https://doi.org/10.3390/antiox10081306 - 18 Aug 2021

Cited by 85 | Viewed by 12261

Abstract

Endothelial dysfunction plays a critical role in atherosclerosis progression, leading to cardiovascular complications. There are significant associations between diabetes mellitus, oxidative stress, and endothelial dysfunction. Oxidative stress is increased by chronic hyperglycemia and acute glucose fluctuations induced by postprandial hyperglycemia in patients with [...] Read more.

Endothelial dysfunction plays a critical role in atherosclerosis progression, leading to cardiovascular complications. There are significant associations between diabetes mellitus, oxidative stress, and endothelial dysfunction. Oxidative stress is increased by chronic hyperglycemia and acute glucose fluctuations induced by postprandial hyperglycemia in patients with diabetes mellitus. In addition, selective insulin resistance in the phosphoinositide 3-kinase/Akt/endothelial nitric oxide (NO) synthase pathway in endothelial cells is involved in decreased NO production and increased endothelin-1 production from the endothelium, resulting in endothelial dysfunction. In a clinical setting, selecting an appropriate therapeutic intervention that improves or augments endothelial function is important for preventing diabetic vascular complications. Hypoglycemic drugs that reduce glucose fluctuations by decreasing the postprandial rise in blood glucose levels, such as glinides, α-glucosidase inhibitors and dipeptidyl peptidase 4 inhibitors, and hypoglycemic drugs that ameliorate insulin sensitivity, such as thiazolidinediones and metformin, are expected to improve or augment endothelial function in patients with diabetes. Glucagon-like peptide 1 receptor agonists, metformin, and sodium-glucose cotransporter 2 inhibitors may improve endothelial function through multiple mechanisms, some of which are independent of glucose control or insulin signaling. Oral administration of antioxidants is not recommended in patients with diabetes due to the lack of evidence for the efficacy against diabetic complications. Full article

► Show Figures

Figure 1

21 pages, 5172 KiB

Open AccessArticle

Early Cytokine-Induced Transient NOX2 Activity Is ER Stress-Dependent and Impacts β-Cell Function and Survival

by Eloisa A. Vilas-Boas, Christopher Carlein, Lisa Nalbach, Davidson C. Almeida, Emmanuel Ampofo, Angelo R. Carpinelli, Leticia P. Roma and Fernanda Ortis

Antioxidants 2021, 10(8), 1305; https://doi.org/10.3390/antiox10081305 - 18 Aug 2021

Cited by 6 | Viewed by 3067

Abstract

In type 1 diabetes (T1D) development, proinflammatory cytokines (PIC) released by immune cells lead to increased reactive oxygen species (ROS) production in β-cells. Nonetheless, the temporality of the events triggered and the role of different ROS sources remain unclear. Isolated islets from C57BL/6J [...] Read more.

In type 1 diabetes (T1D) development, proinflammatory cytokines (PIC) released by immune cells lead to increased reactive oxygen species (ROS) production in β-cells. Nonetheless, the temporality of the events triggered and the role of different ROS sources remain unclear. Isolated islets from C57BL/6J wild-type (WT), NOX1 KO and NOX2 KO mice were exposed to a PIC combination. We show that cytokines increase O₂^•− production after 2 h in WT and NOX1 KO but not in NOX2 KO islets. Using transgenic mice constitutively expressing a genetically encoded compartment specific H₂O₂ sensor, we show, for the first time, a transient increase of cytosolic/nuclear H₂O₂ in islet cells between 4 and 5 h during cytokine exposure. The H₂O₂ increase coincides with the intracellular NAD(P)H decrease and is absent in NOX2 KO islets. NOX2 KO confers better glucose tolerance and protects against cytokine-induced islet secretory dysfunction and death. However, NOX2 absence does not counteract the cytokine effects in ER Ca²⁺ depletion, Store-Operated Calcium Entry (SOCE) increase and ER stress. Instead, the activation of ER stress precedes H₂O₂ production. As early NOX2-driven ROS production impacts β-cells’ function and survival during insulitis, NOX2 might be a potential target for designing therapies against early β-cell dysfunction in the context of T1D onset. Full article

(This article belongs to the Special Issue Hydrogen Peroxide in Redox Signaling)

► Show Figures

Figure 1

15 pages, 903 KiB

Open AccessSystematic Review

Effects of Antioxidant in Adjunct with Periodontal Therapy in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis

by Koji Mizutani, Prima Buranasin, Risako Mikami, Kohei Takeda, Daisuke Kido, Kazuki Watanabe, Shu Takemura, Keita Nakagawa, Hiromi Kominato, Natsumi Saito, Atsuhiko Hattori and Takanori Iwata

Antioxidants 2021, 10(8), 1304; https://doi.org/10.3390/antiox10081304 - 18 Aug 2021

Cited by 13 | Viewed by 4405

Abstract

This review investigated whether the adjunctive use of antioxidants with periodontal therapy improves periodontal parameters in patients with type 2 diabetes. A systematic and extensive literature search for randomized controlled trials (RCTs) conducted before April 2021 was performed on the PubMed, Cochrane Library, [...] Read more.

This review investigated whether the adjunctive use of antioxidants with periodontal therapy improves periodontal parameters in patients with type 2 diabetes. A systematic and extensive literature search for randomized controlled trials (RCTs) conducted before April 2021 was performed on the PubMed, Cochrane Library, and Web of Science databases. The risk of bias was assessed using the Cochrane risk-of-bias tool. A meta-analysis was performed to quantitatively evaluate the clinical outcomes following periodontal therapy. After independent screening of 137 initial records, nine records from eight RCTs were included. The risk-of-bias assessment revealed that all RCTs had methodological weaknesses regarding selective bias, although other risk factors for bias were not evident. This meta-analysis of two RCTs showed that periodontal pocket depths were significantly reduced in the groups treated with combined non-surgical periodontal therapy and melatonin than in those treated with non-surgical periodontal therapy alone. The present systematic review and meta-analysis suggest that the adjunctive use of melatonin, resveratrol, omega-3 fatty acids with cranberry juice, propolis, and aloe vera gel with periodontal therapy significantly improves periodontal disease parameters in patients with type 2 diabetes, and melatonin application combined with non-surgical periodontal therapy might significantly reduce periodontal pocket depth. However, there are still limited studies of melatonin in combination with non-surgical periodontal therapy in Type 2 diabetic patients, and more well-designed RCTs are required to be further investigated. Full article

(This article belongs to the Special Issue Role of Oxidative Stress in Diabetes and Complications: From Biomarkers to Therapeutic Targets)

► Show Figures

Figure 1

16 pages, 6674 KiB

Open AccessArticle

Theoretical Study of Radical Inactivation, LOX Inhibition, and Iron Chelation: The Role of Ferulic Acid in Skin Protection against UVA Induced Oxidative Stress

by Ana Amić, Jasmina M. Dimitrić Marković, Zoran Marković, Dejan Milenković, Žiko Milanović, Marko Antonijević, Denisa Mastiľák Cagardová and Jaime Rodríguez-Guerra Pedregal

Antioxidants 2021, 10(8), 1303; https://doi.org/10.3390/antiox10081303 - 18 Aug 2021

Cited by 17 | Viewed by 3320

Abstract

Ferulic acid (FA) is used in skin formulations for protection against the damaging actions of the reactive oxygen species (ROS) produced by UVA radiation. Possible underlying protective mechanisms are not fully elucidated. By considering the kinetics of proton-coupled electron transfer (PCET) and radical-radical [...] Read more.

Ferulic acid (FA) is used in skin formulations for protection against the damaging actions of the reactive oxygen species (ROS) produced by UVA radiation. Possible underlying protective mechanisms are not fully elucidated. By considering the kinetics of proton-coupled electron transfer (PCET) and radical-radical coupling (RRC) mechanisms, it appears that direct scavenging could be operative, providing that a high local concentration of FA is present at the place of ^•OH generation. The resulting FA phenoxyl radical, after the scavenging of a second ^•OH and keto-enol tautomerization of the intermediate, produces 5-hydroxyferulic acid (5OHFA). Inhibition of the lipoxygenase (LOX) enzyme, one of the enzymes that catalyse free radical production, by FA and 5OHFA were analysed. Results of molecular docking calculations indicate favourable binding interactions of FA and 5OHFA with the LOX active site. The exergonicity of chelation reactions of the catalytic Fe²⁺ ion with FA and 5OHFA indicate the potency of these chelators to prevent the formation of ^•OH radicals via Fenton-like reactions. The inhibition of the prooxidant LOX enzyme could be more relevant mechanism of skin protection against UVA induced oxidative stress than iron chelation and assumed direct scavenging of ROS. Full article

► Show Figures

Graphical abstract

16 pages, 3120 KiB

Open AccessArticle

Acyl Quinic Acid Derivatives Screened Out from Carissa spinarum by SOD-Affinity Ultrafiltration LC–MS and Their Antioxidative and Hepatoprotective Activities

by Ye Liu, Felix Wambua Muema, Yong-Li Zhang and Ming-Quan Guo

Antioxidants 2021, 10(8), 1302; https://doi.org/10.3390/antiox10081302 - 18 Aug 2021

Cited by 14 | Viewed by 3205

Abstract

Carissa spinarum Linn. has been utilized both in the food industry and as a traditional medicine for various ailments, while the responsible chemical components and action mechanisms of its antioxidative and hepatoprotective activities remain unclear. In this work, at least 17 quinic acid [...] Read more.

Carissa spinarum Linn. has been utilized both in the food industry and as a traditional medicine for various ailments, while the responsible chemical components and action mechanisms of its antioxidative and hepatoprotective activities remain unclear. In this work, at least 17 quinic acid derivatives as potential ligands for the superoxide dismutase (SOD) enzyme from Carissa spinarum L. were screened out using the bio-affinity ultrafiltration with liquid chromatography mass spectrometry (UF–LC/MS), and 12 of them (1–12), including, three new ones (1–3), were further isolated by phytochemical methods and identified by high resolution electrospray ionization mass spectrometry (HR-ESI-MS) and extensive nuclear magnetic resonance (NMR) spectroscopic analysis. All of these isolated compounds were evaluated for their antioxidant activities by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and ferric-reducing antioxidant power (FRAP) methods. As a result, compounds 4 and 6–11 displayed similar or better antioxidant activities compared to vitamin C, which is in good agreement with the bio-affinity ultrafiltration with SOD enzyme. Then, these compounds, 4 and 6–11, with better antioxidant activity were further explored to protect the L02 cells from H₂O₂-induced oxidative injury by reducing the reactive oxygen species (ROS) and Malondialdehyde (MDA) production and activating the SOD enzyme. To the best of our knowledge, this is the first report to use an efficient ultrafiltration approach with SOD for the rapid screening and identification of the SOD ligands directly from a complex crude extract of Carissa spinarum, and to reveal its corresponding active compounds with good antioxidative and hepatoprotective activities. Full article

(This article belongs to the Special Issue Antioxidant Agents for the Prevention and Therapy of Oxidative Stress in Hepatic Diseases)

► Show Figures

Graphical abstract

18 pages, 2182 KiB

Open AccessArticle

Effects of Water Deficit Irrigation on Phenolic Composition and Antioxidant Activity of Monastrell Grapes under Semiarid Conditions

by Eva P. Pérez-Álvarez, Diego S. Intrigliolo, María Pilar Almajano, Pilar Rubio-Bretón and Teresa Garde-Cerdán

Antioxidants 2021, 10(8), 1301; https://doi.org/10.3390/antiox10081301 - 18 Aug 2021

Cited by 21 | Viewed by 3407

Abstract

The high phenolic compound content of grapes makes them an important source of natural antioxidants, among other beneficial health properties. Vineyard irrigation might affect berry composition and quality. Regulated deficit irrigation (RDI) is a widely used strategy to reduce the possible negative impact [...] Read more.

The high phenolic compound content of grapes makes them an important source of natural antioxidants, among other beneficial health properties. Vineyard irrigation might affect berry composition and quality. Regulated deficit irrigation (RDI) is a widely used strategy to reduce the possible negative impact of irrigation on grapes, improving grape composition and resulting in water savings. Monastrell grapevines (Vitis vinifera L.) grown in eastern Spain were subjected to two water regime strategies: rainfed (non-irrigation) and RDI. The content of anthocyanins, flavonols, flavanols, hydroxybenzoic and hydroxycinnamic acids, and stilbenes was determined by HPLC and was related with total phenolic content and three antioxidant activity methods (ABTS, DPPH, and ORAC). The study aimed to evaluate and compare the phenolic composition and antioxidant potential of Monastrell grapes. The rainfed regime concentrated grapes in terms of phenolic compounds. Thus, total content of anthocyanins, flavonols, flavanols, hydroxybenzoic acids, and total phenols were higher in the rainfed grapes than in the RDI ones. Besides, the rainfed grapes doubled their antioxidant potential with respect to the RDI grapes with the ORAC method. Total phenolic content and antioxidant activity by ORAC assay positively correlated with most of the total phenolic compounds analyzed. This study demonstrates how field practices can modulate final grape composition in relation to their antioxidant activity. Full article

(This article belongs to the Special Issue Antioxidant Capacity of Vegetables and Foods)

► Show Figures

Figure 1

27 pages, 2643 KiB

Open AccessArticle

Water-Soluble Melanoidin Pigment as a New Antioxidant Component of Fermented Willowherb Leaves (Epilobium angustifolium)

by Daniil N. Olennikov, Christina S. Kirillina and Nadezhda K. Chirikova

Antioxidants 2021, 10(8), 1300; https://doi.org/10.3390/antiox10081300 - 18 Aug 2021

Cited by 16 | Viewed by 4534

Abstract

Willowherb (Epilobium angustifolium L., family Onagraceae) is a well-known food and medicinal plant used after fermentation as a source of beverages with high antioxidant potential. Despite this long history of use, only a few papers have described the chemical profile and bioactivity [...] Read more.

Willowherb (Epilobium angustifolium L., family Onagraceae) is a well-known food and medicinal plant used after fermentation as a source of beverages with high antioxidant potential. Despite this long history of use, only a few papers have described the chemical profile and bioactivity of fermented willowherb tea in general. To understand the basic metabolic differences of non-fermented and fermented E. angustifolium leaves, we used general chemical analysis, high-performance liquid chromatography with photodiode array detection and electrospray ionization triple quadrupole mass spectrometric detection assay, and an isolation technique. As a result, the content of 14 chemical groups of compounds was compared in the two plant materials; 59 compounds were detected, including 36 new metabolites; and a new water-soluble phenolic polymer of melanoidin nature was isolated and characterized. The fundamental chemical shifts in fermented E. angustifolium leaves relate mainly to the decrease of ellagitannin content, while there is an increase of melanoidin percentage and saving of the antioxidant potential, despite the significant changes detected. The strong antioxidative properties of the new melanoidin were revealed in a series of in vitro bioassays, and a simulated gastrointestinal and colonic digestion model demonstrated the stability of melanoidin and its antioxidant activity. Finally, we concluded that the new melanoidin is a basic antioxidant of the fermented leaves of E. angustifolium, and it can be recommended for additional study as a promising food and medicinal antioxidant agent. Full article

(This article belongs to the Special Issue Antioxidant Capacity of Vegetables and Foods)

► Show Figures

Figure 1

12 pages, 10019 KiB

Open AccessArticle

Tumor-Induced Cardiac Dysfunction: A Potential Role of ROS

by Priyanka Karekar, Haley N. Jensen, Kathryn L. G. Russart, Devasena Ponnalagu, Sarah Seeley, Shridhar Sanghvi, Sakima A. Smith, Leah M. Pyter, Harpreet Singh and Shubha Gururaja Rao

Antioxidants 2021, 10(8), 1299; https://doi.org/10.3390/antiox10081299 - 18 Aug 2021

Cited by 6 | Viewed by 6099

Abstract

Cancer and heart diseases are the two leading causes of mortality and morbidity worldwide. Many cancer patients undergo heart-related complications resulting in high incidences of mortality. It is generally hypothesized that cardiac dysfunction in cancer patients occurs due to cardiotoxicity induced by therapeutic [...] Read more.

Cancer and heart diseases are the two leading causes of mortality and morbidity worldwide. Many cancer patients undergo heart-related complications resulting in high incidences of mortality. It is generally hypothesized that cardiac dysfunction in cancer patients occurs due to cardiotoxicity induced by therapeutic agents, used to treat cancers and/or cancer-induced cachexia. However, it is not known if localized tumors or unregulated cell growth systemically affect heart function before treatment, and/or prior to the onset of cachexia, hence, making the heart vulnerable to structural or functional abnormalities in later stages of the disease. We incorporated complementary mouse and Drosophila models to establish if tumor induction indeed causes cardiac defects even before intervention with chemotherapy or onset of cachexia. We focused on one of the key pathways involved in irregular cell growth, the Hippo–Yorkie (Yki), pathway. We used overexpression of the transcriptional co-activator of the Yki signaling pathway to induce cellular overgrowth, and show that Yki overexpression in the eye tissue of Drosophila results in compromised cardiac function. We rescue these cardiac phenotypes using antioxidant treatment, with which we conclude that the Yki induced tumorigenesis causes a systemic increase in ROS affecting cardiac function. Our results show that systemic cardiac dysfunction occurs due to abnormal cellular overgrowth or cancer elsewhere in the body; identification of specific cardiac defects associated with oncogenic pathways can facilitate the possible early diagnosis of cardiac dysfunction. Full article

(This article belongs to the Special Issue Oxidative Stress in Cardiac Disease)

► Show Figures

Graphical abstract

Journal Menu

Journal Browser

Antioxidants, Volume 10, Issue 8 (August 2021) – 173 articles

Further Information

Guidelines

MDPI Initiatives

Follow MDPI