Search Results (2,336)

In recent decades, chemotherapy has significantly improved cancer survival, yet its adverse effects on non-cancerous tissues raise increasing concerns. In this context, growing attention has been focused on natural compounds that may be useful in mitigating the undesirable effects of chemotherapeutic agents. Here, we aimed to demonstrate that Cytosporone B (CsnB) is a potent agent for counteracting the cardiovascular effects induced by Imatinib. To this end, 12-week-old male Wistar rats were studied; they were divided into three groups as follows: (1) control, (2) Imatinib-treated (Imatinib: 60 mg/kg/day, per os), (3) Imatinib + CsnB-treated (CsnB: 5 mg/kg/day, i.p.). After the two-week-long experimental period, rats were euthanized. Their hearts were used for the following biochemical measurements: NADPH oxidase (NOX4), high mobility group box 1 (HMGB1), peptidylarginine deiminase 4 (PAD4), inducible nitric oxide synthase (iNOS) expression, tumor necrosis factor-alpha (TNF-α) level, and myeloperoxidase (MPO) activity. Imatinib caused a marked upregulation of key inflammatory and oxidative markers, including HMGB1, TNF-α, MPO, iNOS, PAD4, and NOX4 in cardiac tissue; however, CsnB treatment mitigated these elevations, implying its role in opposing Imatinib-induced inflammatory and oxidative processes in the heart. Our findings suggest that CsnB holds promise as a cardioprotective agent capable of modulating Imatinib-induced adverse cardiac effects. Full article

In left ventricular hypertrophy (LVH), the combined external administration of hydrogen sulfide (H₂S) and nitric oxide (NO) has been shown to reverse LVH by activating the endothelial nitric oxide synthase pathway (eNOS/NO), independent of the cystathionine γ-lyase (CSE/H₂S) pathway. Individually, both H₂S and NO have also been reported to significantly improve RCBP, restore renal excretory performance, and enhance α-adrenergic receptor responsiveness in rats. The induction of LVH was performed over a period of two weeks using drinking water with caffeine and isoprenaline. Five weeks later, the rats were fed with L-arginine (1.25 g/L) as a nitrogen oxide donor. Vascular reactions to methoxamine, phenylephrine, and noradrenaline were assessed in presences and absence of 5-methylurapidil (5-MeU), BMY7378, and chloroethylclonidine (CeC) and α1-adrenoceptor antagonists. In both the Control WKY and LVH-WKY groups, combined H₂S+NO therapy significantly (p < 0.05) upregulated the renal mRNA of CSE and eNOS when compared with untreated LVH rats. The treatment also markedly increased RCBP in LVH-H₂S+NO rats relative to LVH controls. Furthermore, H₂S+NO administration enhanced the activity of α_1A, α_1B, and α_1D adrenergic receptors in mediating renal vasoconstriction. Even under receptor blockade with high doses (HDs) of 5-MeU, CeC, and BMY 7378, renal vasoconstriction responses to adrenergic agonists like NA, PE, and ME in the LVH-H₂S+NO group remained comparable to those observed in the counterpart Control-H₂S+NO group. The findings of current study suggest that simultaneous exogenous administration of H₂S and NO donors improve renal cortical blood flow, support renal function, and augment α_1A, α_1B, and α_1D adrenergic receptor responsiveness to adrenergic agonists like NA, PE, and ME in LVH rats. This effect appears to rely primarily on the eNOS/NO pathway, with partial contribution from the CSE/H₂S pathway. Full article

In recent years, chitosan oligosaccharide (COS) has demonstrated promising applications in enhancing the immune protective function of sea cucumbers. However, the immune-protective effect of COS on sea cucumber coelomocytes in vitro remains unclear. This study investigated the effect of COS on lipopolysaccharide (LPS)-stimulated inflammation in sea cucumber coelomocytes. First, we measured the effects of COS and LPS on the viability of coelomocytes. COS exhibited no toxic effects on sea cucumber coelomocytes. Furthermore, pre-incubating the coelomocytes with COS significantly improved coelomocytes’ viability after LPS stimulation (p < 0.05). Secondly, the phagocytic activity and respiratory burst of the coelomocytes were assessed to evaluate their immune levels. COS alone significantly increased the respiratory burst and phagocytic activity of the coelomocytes (p < 0.05). However, with LPS stimulated, COS significantly increased both the respiratory burst and phagocytic activity of the coelomocytes. The activities of lysozyme (Lyz), total nitric oxide synthase (T-NOSs), and superoxide dismutase (SOD) in sea cucumber coelomocytes were measured to evaluate their response to LPS stimulation. The results indicated that LPS stimulation significantly increases the activities of Lyz, T-NOSs, and SOD in sea cucumber coelomocytes (p < 0.05). Additionally, it was found that COS could inhibit the LPS-mediated expression of Lyz, T-NOSs, and SOD activities in the coelomocytes (p < 0.05). Furthermore, the relative expression of six immune-related genes—Aj-IL-17, Aj-TNF-α, Aj-i-Lys, Aj-NOS, Aj-Rel, Aj-P105—were analyzed in the coelomocytes stimulated by LPS after being cultured with COS. Finally, through transcriptomic technology analysis, it was determined that COS primarily alleviates LPS-induced inflammation via the tumor necrosis factor signaling pathway and the phagosome signaling pathway. The findings demonstrated that COS inhibited the expression of immune genes in sea cucumber coelomocytes in a dose-dependent manner. In summary, pretreatment with chitosan oligosaccharides appears to confer an immune protective role in LPS-stimulated sea cucumber coelomocytes. Full article

Hypocrellin A (HA), a photodynamic perylenequinone pigment from Shiraia fruiting bodies, functions as an efficient photosensitizer for clinical photodynamic therapy. Glucose-6-phosphate dehydrogenase (G6PDH), the rate-limiting enzyme of the pentose phosphate pathway (PPP), governs carbon flux into NADPH production. This study elucidates G6PDH’s regulatory role in HA biosynthesis in Shiraia sp. S9. Bamboo polysaccharide (BPS) elicitation (100 mg/L) significantly enhanced HA production to 428.1 mg/L, 1.6-fold higher than controls after 5 days. We cloned the G6PDH gene and demonstrated that BPS upregulated its expression and activity, concomitant with increased reactive oxygen species (ROS; H₂O₂ and O₂^•−) and nitric oxide (NO) generation. ROS production was mediated by NADPH oxidase induction, while NO generation was attributed to elevated nitric oxide synthase and nitrate reductase activities. Critically, the G6PDH inhibitor glucosamine (1.0 mM) suppressed both H₂O₂ and NO production. These ROS/NO signals upregulated key HA biosynthetic (PKS, Omef) and transport (MFS) genes. Our findings establish G6PDH as a central regulator of BPS-induced HA biosynthesis via ROS/NO signaling, revealing novel metabolic crosstalk between the PPP and fungal perylenequinone biosynthesis. This work presents BPS elicitation as a biotechnological strategy for scalable HA production in Shiraia mycelium cultures. Full article

Cerebral vasospasm (CVS) following a subarachnoid hemorrhage (SAH) is a critical complication driven by imbalances between vasodilators and vasoconstrictors. This review explores the bidirectional interplay between nitric oxide (NO) and endothelin-1 (ET-1) in CVS pathogenesis. NO, a potent vasodilator mainly produced by endothelial and neuronal nitric oxide synthase (eNOS/nNOS) under normal physiological conditions, is scavenged early after SAH by hemoglobin derivatives, leading to microcirculatory dysfunction, pericyte constriction, and impaired neurovascular coupling. Conversely, ET-1 exacerbates vasoconstriction by suppressing NO synthesis via ROS-dependent eNOS uncoupling and Rho-kinase activation. The NO/ET-1 axis further influences delayed cerebral ischemia (DCI) through mechanisms like 20-HETE-mediated cGMP suppression and oxidative stress. Emerging therapies—including NO donors, NOS gene therapy, and ET-1 receptor antagonists—aim to restore this balance. Understanding these pathways offers translational potential for mitigating CVS and improving outcomes post-SAH. Full article

Background/Objectives: Enhancing endothelial nitric oxide (NO) bioavailability through natural products may provide a promising strategy for the prevention and management of hypertension. This study investigated the phytochemical composition of ethanolic lotus (Nelumbo nucifera) seed extract (LSE), its vasorelaxant mechanisms, effects on endothelial NO production, and antihypertensive activity. Methods: LSE was characterized via LC-ESI-QTOF-MS using accurate mass data and fragmentation patterns. Vasorelaxant effects were evaluated in isolated rat aortas, and the underlying mechanisms were explored using pharmacological inhibitors. NO production was assessed in human endothelial EA.hy926 cells. Hypotensive activity was examined in normotensive rats following intravenous administration of LSE (10, 30, and 100 mg/kg). Molecular docking was performed to analyze interactions between LSE bioactive compounds and endothelial nitric oxide synthase (eNOS). Results: LC-ESI-QTOF-MS analysis identified 114 compounds, including primary and secondary metabolites. LSE induced vasorelaxation in endothelium-intact aortas, which was reduced by endothelium removal (p < 0.001) and by L-NAME (p < 0.001). LSE also inhibited receptor-operated, Ca²⁺ channel-mediated vasoconstriction (p < 0.05). In vivo, LSE decreased blood pressure in a dose-dependent manner. In EA.hy926 cells, LSE (750 and 1000 µg/mL) increased NO production, an effect attenuated by L-NAME. Molecular docking showed that LSE alkaloids, including nelumborine, nelumboferine, neferine, and isoliensinine had strong affinities for binding with eNOS at the tetrahydrobiopterin (BH4) binding site. Nelumborine exhibited the highest affinity, suggesting its potential as an eNOS modulator. Conclusions: LSE promotes vasorelaxation through the stimulation of endothelium-derived NO release and Ca²⁺ influx inhibition, contributing to blood pressure reduction. These findings support LSE as a potential natural antihypertensive supplement. Full article

Background: Parkinson’s disease (PD) is a neurodegenerative disorder for which no curative therapies currently exist. Experimental models employing 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) reproduce PD features such as striatal dopaminergic dysfunction and motor deficits. Various MPTP dosing regimens are used to screen drug candidates for PD, but their validity is limited because of the predominant use of young male animals. Sex bias is another issue that is underrepresented in PD research, since females are more susceptible to this pathology. Here, we studied the model of bolus administration of MPTP (30 mg/kg) in aged female mice and assessed its sensitivity to the antioxidants fullerene C₆₀ and fullerenol C₆₀(OH)₂₄, given that oxidative stress is a key contributor to PD. Methods: 12-month-old female C57BL/6 mice received fullerene (0.1 mg/kg/day, via diet) or fullerenol (0.15 mg/kg/day, via drinking water). On day 10, mice were injected with MPTP. We studied tremor, piloerection, and behavior in the pole test, rotarod, pole test, and open field. High-performance liquid chromatography (HPLC) was employed to study dopaminergic neurotransmission, and the expression levels of its molecular regulators and nitric oxide synthase (NOS)-related targets were investigated using RT-PCR in the striatum and cortex. Results: MPTP-challenged mice displayed profound impairment in markers of dopaminergic neurotransmission and cellular distress, and showed disrupted motor behavior and vegetative functions. Antioxidant-treated animals that received a bolus injection of MPTP demonstrated partial preservation of tremor response, dopaminergic parameters, and iNOS and nNOS gene expression, although motor performance in the pole test was only modestly improved. Fullerenol appeared more effective in decreasing MPTP-induced neurochemical changes. Conclusions: The applied MPTP model showed its validity in mimicking PD features and was sensitive to low doses of antioxidants, suggesting its usefulness for screening drugs that target oxidative and nitrosative stress. The neuroprotective effects of fullerene-based compounds suggest their potential utility in the treatment of PD. Full article

The development of dressing materials mainly protects the wound, prevents infection, and assists in wound healing. Apart from the most common gauze on the market, different dressing materials can accelerate wound healing. Bacterial cellulose (BC) dressings have had many related studies and applications so far, and other natural or artificial compounds that are beneficial to tissue repair may also be added during the manufacturing process. This study compared the wound healing efficacies of BC dry membrane developed by our team, gauze, commercially available “Tegaderm^TM Hydrocolloid Dressing”, and “AQUACEL^® EXTRA Hydrofiber Dressing”. This study used rats as experimental animals and injured them by scalding. Moreover, Staphylococcus aureus was used to infect wounds to compare the effects on wound healing. We first used NIH-3T3 cells for an in vitro model to confirm that the BC membrane is not harmful to cells. In the animal experiment, wounds were created by scalding and then treated with different dressing materials and doses of S. aureus. After 10 days of treatment, the wound recovery in the BC membrane and AQUACEL^® groups was the most obvious, including angiogenesis in the dermal layer and regeneration of the epidermis layer. Especially without S. aureus infection, inflammatory markers such as cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expression levels were reduced to those of healthy tissue. In conclusion, we confirmed that the BC dry membrane can accelerate wound healing. In the future, it may provide high-efficiency and less expensive options in the dressing market. Full article

Exposure to hypoxia at high altitudes is significantly associated with impairments in learning and memory functions, as well as abnormalities in neuronal function and synaptic plasticity. Recent research has indicated that mitochondrial reactive oxygen species (mtROS) play a role in regulating microglial activation and mediating neurotoxic damage in the hippocampal CA1 region. Nicotinamide riboside (NR), upon absorption, is rapidly converted into nicotinamide adenine dinucleotide (NAD+), which is involved in the production of mitochondrial adenosine triphosphate (ATP). The potential of NR to protect dendritic spine plasticity in hippocampal CA1 neurons following hypoxia exposure, potentially through the inhibition of microglial activation, warrants further investigation. To this end, a mouse model simulating hypoxia at an altitude of 6000 m over a two-week period, along with a BV2 cells and conditional co-culture of BV2 cells and HT22 cells 1%O₂ hypoxia model, was developed. Behavioral assessments indicated that, relative to the normoxia group, mice subjected to hypoxia exhibited a significant reduction in the time spent in the target quadrant, the distance traveled within the target quadrant, the number of platform crossings, and the novel object recognition index. Furthermore, Golgi staining revealed a marked decrease in the density of dendritic spines in the hippocampal CA1 region in the hypoxia-exposed mice compared to the normoxia group. Subsequently, A daily dosage of 400 mg/kg of NR was administered for two weeks and 0.5 mM NR was used in a conditional co-culture model. Results demonstrated that, in comparison to the hypoxia group, the group receiving combined hypoxia and NR treatment showed significant improvements in the time spent in the target quadrant, the distance traveled within the target quadrant, the number of platform crossings, the novel object recognition index, and the density of dendritic spines in the hippocampal CA1 region. Additionally, transmission electron microscopy indicated a significant increase in the synaptic density of hippocampal neurons in the combined hypoxia exposure and NR treatment group compared to the hypoxia exposure group. Simultaneously, when compared to the hypoxia group, the combination of hypoxia and NR treatment resulted in an increased concentration of mitochondrial ATP. This treatment also partially restored mitochondrial membrane integrity, reduced mtROS levels, decreased the percent of Iba1⁺CD68⁺Iba1⁺ microglia, and lowered the interleukin-1β (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-α (TNFα), and inducible nitric oxide synthase (iNOS) mRNA levels. These findings indicate that NR treatment may mitigate neurotoxic damage in the hippocampal CA1 region induced by hypoxia exposure, primarily through the attenuation of microglial activation and the reduction in mtROS production. Full article

Background/Objectives: The rapid progression of stroke often results in irreversible brain damage and poor outcomes when treatment is delayed. Prophylactic administration of FAD012 (3,5-dimethyl-4-hydroxycinnamic acid), a synthetic derivative of ferulic acid (FA), has demonstrated cerebroprotective effects in ischemic models through antioxidant and endothelial protective mechanisms. This study investigated the effects of FAD012 on cerebral infarction and blood–brain barrier (BBB) integrity using a photothrombotic stroke model in rats. Methods: Male Sprague Dawley rats received a single intraperitoneal injection of FAD012 or FA (100 or 300 mg/kg) 60 min prior to stroke induction. Under isoflurane anesthesia, the middle cerebral artery was exposed, and stroke was induced by intravenous administration of Rose Bengal followed by green laser irradiation. Cerebral blood flow (CBF) was monitored by laser Doppler flowmetry. BBB disruption was evaluated by Evans Blue extravasation and immunohistochemistry for tight junction (TJ) proteins. Results: Control rats exhibited extensive infarction, BBB disruption, and reduced expression of claudin-5, occludin, and ZO-1, along with fragmented collagen IV. In contrast, FAD012 (300 mg/kg) significantly attenuated CBF reduction, reduced infarct size, preserved BBB integrity, and maintained TJ protein expression, with greater efficacy than an equivalent dose of FA. FAD012 also preserved the expression and phosphorylation of endothelial nitric oxide synthase (eNOS), a key marker of vascular integrity. The CBF-preserving effect of FAD012 was completely abolished by N^G-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor. Conclusions: These findings suggest that FAD012 protects endothelial function, thereby contributing to the maintenance of CBF and BBB integrity, supporting its potential as a prophylactic therapeutic agent for ischemic stroke. Full article

Background: Nitric oxide (NO) is a gaseous free radical produced from L-arginine by the nitric oxide synthase (NOS) enzymes. NO exerts a dose-dependent biphasic effect on lung cancer development, angiogenesis, and dissemination. The widespread contribution of nitric oxide signaling to lung cancer biology has cast a spotlight on the identification of NO-based therapeutic approaches as well as the use of fractional exhaled NO (FeNO) as a prognostic biomarker of clinical control. However, the significance of lung cancer treatment and prognosis has not been fully elucidated. Objective: This narrative review gives an overview of NO in lung cancer, focusing on its therapeutic and prognostic implications. Results: FeNO may help to assess the complications associated with non-pharmacological treatments, including postoperative pneumonia and radiation pneumonitis. By contrast, the role of FeNO dynamics during pharmacological treatment is still largely unexplored due to the suppressive effect of chemotherapy on FeNO levels. The rise of immunotherapy may pave the way to a better evaluation of FeNO as a prognostic biomarker of treatment response. The dichotomous involvement of NO in lung cancer events has led to the adoption of several NO-centered treatments that are focused on both inhibiting and enhancing NO signaling. However, NO chemical and biological characteristics have hindered its implementation in clinical practice. Conclusions: In the coming years, the advancements in drug delivery systems may lead to more effective anti-cancer applications of NO by improving tumor targeting and minimizing the systemic side effects. Together, our findings emphasize the promising role of NO in lung cancer treatment, underscoring the challenges and avenues for future research. Full article

Traumatic brain injury (TBI), even when mild, has been associated with the presence of depression. Depression is a mood disorder characterized by persistent negative thoughts and sadness and is challenging to treat due to the multiple mechanisms involved in its pathophysiology, including increased nitric oxide (NO) levels. There are no completely safe and effective pharmacological strategies to treat this disorder. Mucuna pruriens (MP) has been shown to possess neuroprotective properties by regulating inflammatory responses and nitric oxide synthase activity. In this study, we evaluated the antidepressant-like effect of MP in male Wistar rats with induced mild traumatic brain injury (mTBI). MP extract (50 mg/kg i.p.) was administered immediately after mTBI and every 24 h for five days. We used the rats’ preference for sucrose consumption to assess the presence of depression-like behavior and analyzed the nitrite and nitrate levels in their cerebral cortex, striatum, midbrain, and nucleus accumbens. Untreated animals with mTBI showed a reduced preference for sucrose than those treated with MP, whose preference for sucrose was similar to that of sham animals. Increased nitrite and nitrate levels were observed in different brain regions in the TBI subjects; however, this increase was not observed in MP-treated animals. MP reduces behavior associated with depression and the brain NO levels in rats with mTBI. Full article

Zanthoxyli Pericarpium (ZP), the dried pericarp of mature fruits of Zanthoxylum schinifolium Siebold and Zucc., has traditionally been used in East Asian medicine for its medicinal properties, but its therapeutic potential in periodontitis has not been elucidated. In the present study, we investigated the effects of ZP on ligature-induced experimental periodontitis (EPD) in male Sprague Dawley rats. Animals were assigned to vehicle control, ligature control, ZP-treated (25, 50, and 100 mg/kg), or indomethacin-treated (5 mg/kg) groups (n = 10 per group) and orally administered the respective treatments daily for 10 days after ligature placement. ZP significantly reduced anaerobic bacterial proliferation and inflammatory cell infiltration in gingival tissue. ZP suppressed the production of inflammatory mediators, such as tumor necrosis factor-α and interleukin-1β, in both gingival tissues and lipopolysaccharide-stimulated RAW 264.7 macrophages, through inhibition of the mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) signaling pathways. In addition, ZP decreased myeloperoxidase activity and reduced matrix metalloproteinase-8 expression, thereby preserving collagen areas. ZP also restored the receptor activator of NF-κB ligand/osteoprotegerin (RANKL/OPG) balance, leading to a reduction in osteoclast numbers and their occupancy on the alveolar surface, and it effectively ameliorated horizontal alveolar bone loss. Furthermore, ZP exhibited antioxidant effects by lowering malondialdehyde levels and inducible nitric oxide synthase activity in gingival tissues. Statistical analysis was performed using ANOVA followed by a post hoc test, with significance set at p < 0.05. These findings indicate that ZP mitigates periodontitis through combined antimicrobial, anti-inflammatory, antioxidant, and anti-resorptive actions, supporting its potential as a therapeutic candidate for periodontitis. Full article

Background: The pathophysiology of Alzheimer’s disease (AD) is strongly linked to damage to the cholinergic systems of the central nervous system (CNS), mainly due to the formation of β-amyloid peptide plaques, which trigger intense inflammatory responses and are currently the main cause of the symptoms of the disease. Among the therapeutic strategies under investigation, classes of natural products with immunomodulatory properties, action on the CNS, and potent antioxidant activity, which contribute to neuroprotection, stand out. Methods: We aimed to evaluate the flavonoid quercetin using in silico, in vitro, and in vivo methods for the treatment of AD. Initially, the compounds were selected, and molecular dynamics simulations were performed. The in vitro assays included tests of antioxidant activity (DPPH), enzymatic inhibition of acetylcholinesterase (AChE), and prediction of oral toxicity. The in vivo studies investigated the effects on scopolamine-induced learning deficits and conducted histopathological analysis of the brain. Results: Quercetin showed structural stability in the complex with (AChE), with no significant alterations in the Root Mean Square Deviation (RMSD), SASA and radius of gyration (Rg) parameters. Through the same method it was possible to predict stability between the quercetin and inducible nitric oxide synthase (iNOS) complex, a possible mechanism for quercetin immunomodulation in the CNS. In the AChE inhibition test, the IC₅₀ obtained for quercetin was 59.15 μg mL⁻¹, while in the antioxidant test with DPPH, the concentration of 33.1 µM exhibited 50% of the scavenging of reactive oxygen species. This corroborates the perspective of quercetin having neuroprotective activity. This activity was also corroborated in vivo, in a zebrafish model, in which quercetin reduced the cognitive deficit induced by scopolamine. Histopathological analysis revealed its ability to prevent atrophy, caused by scopolamine, in the nervous tissue of animals, reinforcing the potential of quercetin as a neuroprotective agent. Conclusions: The results of the tests carried out with quercetin suggest that this molecule has antioxidant, AChE inhibitory, and neuroprotective activities, making it a good candidate for use in future clinical trials to ensure its efficacy and safety. Full article

Herpes simplex virus-1 (HSV-1) is a neurotropic virus that can infect the brain, and an uncontrolled infection can lead to severe encephalitis. NO can exert both antiviral as well as cytotoxic effects in the central nervous system (CNS) depending on its concentration and site of infection. In this study, we report that treatment of an intranasal murine HSV-1 infection with aminoguanidine (AMG) decreases both neuroinflammation and neurodegeneration markers, but its positive effect depends on the time of treatment. Specifically, early treatment with AMG impaired the activation of microglia/monocytes, leading to decreased virus-specific antiviral response and higher viral titers in the brain. However, AMG treatment during the peak of brain infection significantly improved antiviral response, reduced inflammation and improved general clinical score. We also found that treatment with AMG decreased beta amyloid levels during both primary and latent infections and protected from the accumulation of phosphorylated Tau protein during early infection. Our findings position inducible nitric oxide synthetase (iNOS) as a potential therapeutic target for mitigating virus-induced neuroinflammation and neurodegeneration. Full article