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Mar. Drugs, Volume 14, Issue 9 (September 2016) – 14 articles

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3087 KiB  
Article
Depolymerization of Fucosylated Chondroitin Sulfate with a Modified Fenton-System and Anticoagulant Activity of the Resulting Fragments
by Jun-hui Li, Shan Li, Zi-jian Zhi, Lu-feng Yan, Xing-qian Ye, Tian Ding, Lei Yan, Robert John Linhardt and Shi-guo Chen
Mar. Drugs 2016, 14(9), 170; https://doi.org/10.3390/md14090170 - 21 Sep 2016
Cited by 50 | Viewed by 6827
Abstract
Fucosylated chondroitin sulfate (fCS) from sea cucumber Isostichopus badionotus (fCS-Ib) with a chondroitin sulfate type E (CSE) backbone and 2,4-O-sulfo fucose branches has shown excellent anticoagulant activity although has also show severe adverse effects. Depolymerization represents an effective method [...] Read more.
Fucosylated chondroitin sulfate (fCS) from sea cucumber Isostichopus badionotus (fCS-Ib) with a chondroitin sulfate type E (CSE) backbone and 2,4-O-sulfo fucose branches has shown excellent anticoagulant activity although has also show severe adverse effects. Depolymerization represents an effective method to diminish this polysaccharide’s side effects. The present study reports a modified controlled Fenton system for degradation of fCS-Ib and the anticoagulant activity of the resulting fragments. Monosaccharides and nuclear magnetic resonance (NMR) analysis of the resulting fragments indicate that no significant chemical changes in the backbone of fCS-Ib and no loss of sulfate groups take place during depolymerization. A reduction in the molecular weight of fCS-Ib should result in a dramatic decrease in prolonging activated partial thromboplastin time and thrombin time. A decrease in the inhibition of thrombin (FIIa) by antithromin III (AT III) and heparin cofactor II (HCII), and the slight decrease of the inhibition of factor X activity, results in a significant increase of anti-factor Xa (FXa)/anti-FIIa activity ratio. The modified free-radical depolymerization method enables preparation of glycosaminoglycan (GAG) oligosaccharides suitable for investigation of clinical anticoagulant application. Full article
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Article
Molecular Weight-Dependent Immunostimulative Activity of Low Molecular Weight Chitosan via Regulating NF-κB and AP-1 Signaling Pathways in RAW264.7 Macrophages
by Bin Zheng, Zheng-Shun Wen, Yun-Juan Huang, Mei-Sheng Xia, Xing-Wei Xiang and You-Le Qu
Mar. Drugs 2016, 14(9), 169; https://doi.org/10.3390/md14090169 - 20 Sep 2016
Cited by 40 | Viewed by 6931
Abstract
Chitosan and its derivatives such as low molecular weight chitosans (LMWCs) have been found to possess many important biological properties, such as antioxidant and antitumor effects. In our previous study, LMWCs were found to elicit a strong immunomodulatory response in macrophages dependent on [...] Read more.
Chitosan and its derivatives such as low molecular weight chitosans (LMWCs) have been found to possess many important biological properties, such as antioxidant and antitumor effects. In our previous study, LMWCs were found to elicit a strong immunomodulatory response in macrophages dependent on molecular weight. Herein we further investigated the molecular weight-dependent immunostimulative activity of LMWCs and elucidated its mechanism of action on RAW264.7 macrophages. LMWCs (3 kDa and 50 kDa of molecular weight) could significantly enhance the mRNA expression levels of COX-2, IL-10 and MCP-1 in a molecular weight and concentration-dependent manner. The results suggested that LMWCs elicited a significant immunomodulatory response, which was dependent on the dose and the molecular weight. Regarding the possible molecular mechanism of action, LMWCs promoted the expression of the genes of key molecules in NF-κB and AP-1 pathways, including IKKβ, TRAF6 and JNK1, and induced the phosphorylation of protein IKBα in RAW264.7 macrophage. Moreover, LMWCs increased nuclear translocation of p65 and activation of activator protein-1 (AP-1, C-Jun and C-Fos) in a molecular weight-dependent manner. Taken together, our findings suggested that LMWCs exert immunostimulative activity via activation of NF-κB and AP-1 pathways in RAW264.7 macrophages in a molecular weight-dependent manner and that 3 kDa LMWC shows great potential as a novel agent for the treatment of immune suppression diseases and in future vaccines. Full article
(This article belongs to the Collection Marine Polysaccharides)
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Article
Dioxinodehydroeckol Enhances the Differentiation of Osteoblasts by Regulating the Expression of Phospho-Smad1/5/8
by Byul-Nim Ahn, Fatih Karadeniz, Chang-Suk Kong, Ki-Ho Nam, Mi-Soon Jang, Youngwan Seo and Han Seong Kim
Mar. Drugs 2016, 14(9), 168; https://doi.org/10.3390/md14090168 - 14 Sep 2016
Cited by 9 | Viewed by 5708
Abstract
Lack of bone formation-related health problems are a major problem for the aging population in the modern world. As a part of the ongoing trend of developing natural substances that attenuate osteoporotic bone loss conditions, dioxinodehydroeckol (DHE) from edible brown alga Ecklonia cava [...] Read more.
Lack of bone formation-related health problems are a major problem for the aging population in the modern world. As a part of the ongoing trend of developing natural substances that attenuate osteoporotic bone loss conditions, dioxinodehydroeckol (DHE) from edible brown alga Ecklonia cava was tested for its effects on osteoblastogenic differentiation in MC3T3-E1 pre-osteoblasts. DHE was observed to successfully enhance osteoblast differentiation, as indicated by elevated cell proliferation, alkaline phosphatase activity, intracellular cell mineralization, along with raised levels of osteoblastogenesis indicators at the concentration of 20 μM. Results suggested a possible intervening of DHE on the bone morphogenetic protein (BMP) signaling pathway, according to elevated protein levels of BMP-2, collagen-I, and Smads. In addition, the presence of DHE was also able to raise the phosphorylated extracellular signal–regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) levels which are also activated by the BMP signaling pathway. In conclusion, DHE is suggested to be a potential bioactive compound against bone loss that could enhance osteoblastogenesis with a suggested BMP pathway interaction. Full article
(This article belongs to the Special Issue Marine Natural Products that Target Metabolic Disorders)
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Review
An Overview of the Medical Applications of Marine Skeletal Matrix Proteins
by M. Azizur Rahman
Mar. Drugs 2016, 14(9), 167; https://doi.org/10.3390/md14090167 - 12 Sep 2016
Cited by 12 | Viewed by 6970
Abstract
In recent years, the medicinal potential of marine organisms has attracted increasing attention. This is due to their immense diversity and adaptation to unique ecological niches that has led to vast physiological and biochemical diversification. Among these organisms, marine calcifiers are an abundant [...] Read more.
In recent years, the medicinal potential of marine organisms has attracted increasing attention. This is due to their immense diversity and adaptation to unique ecological niches that has led to vast physiological and biochemical diversification. Among these organisms, marine calcifiers are an abundant source of novel proteins and chemical entities that can be used for drug discovery. Studies of the skeletal organic matrix proteins of marine calcifiers have focused on biomedical applications such as the identification of growth inducing proteins that can be used for bone regeneration, for example, 2/4 bone morphogenic proteins (BMP). Although a few reports on the functions of proteins derived from marine calcifiers can be found in the literature, marine calcifiers themselves remain an untapped source of proteins for the development of innovative pharmaceuticals. Following an overview of the current knowledge of skeletal organic matrix proteins from marine calcifiers, this review will focus on various aspects of marine skeletal protein research including sources, biosynthesis, structures, and possible strategies for chemical or physical modification. Special attention will be given to potential medical applications and recent discoveries of skeletal proteins and polysaccharides with biologically appealing characteristics. In addition, I will introduce an effective protocol for sample preparation and protein purification that includes isolation technology for biopolymers (of both soluble and insoluble organic matrices) from coralline algae. These algae are a widespread but poorly studied group of shallow marine calcifiers that have great potential for marine drug discovery. Full article
(This article belongs to the Special Issue Marine Proteins and Peptides)
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Article
R-Phycoerythrin Induces SGC-7901 Apoptosis by Arresting Cell Cycle at S Phase
by Huixin Tan, Shiyong Gao, Yan Zhuang, Yanhong Dong, Wenhui Guan, Kun Zhang, Jian Xu and Jingru Cui
Mar. Drugs 2016, 14(9), 166; https://doi.org/10.3390/md14090166 - 12 Sep 2016
Cited by 27 | Viewed by 7852
Abstract
R-Phycoerythrin (R-PE), one of the chemical constituents of red algae, could produce singlet oxygen upon excitation with the appropriate radiation and possibly be used in photodynamic therapy (PDT) for cancer. Documents reported that R-PE could inhibit cell proliferation in [...] Read more.
R-Phycoerythrin (R-PE), one of the chemical constituents of red algae, could produce singlet oxygen upon excitation with the appropriate radiation and possibly be used in photodynamic therapy (PDT) for cancer. Documents reported that R-PE could inhibit cell proliferation in HepG2 and A549 cells, which was significative for cancer therapy. This is due to the fact that R-PE could kill cancer cells directly as well as by PDT. However, little is known about the cytotoxicity of R-PE to the SGC-7901 cell. In this study, it has been found that R-PE could inhibit SGC-7901 proliferation and induce cell apoptosis, which was achieved by arresting the SGC-7901 cell at S phase. CyclinA, CDK2 and CDC25A are proteins associated with the S phase, and it was found that R-PE could increase the expression of cyclin A protein and decrease the expression of CDK2 and CDC25A proteins. Thus, it was concluded that R-PE reduced the CDK2 protein activated through decreasing the CDC25A factor, which reduced the formation of Cyclin-CDK complex. The reduction of Cyclin-CDK complex made the SGC-7901 cells arrest at the S phase. Therefore, R-PE induced apoptosis by arresting the SGC-7901 cell at S phase was successful, which was achieved by the expression of the CDC25A protein, which reduced the CDK2 protein actived and the formation of Cyclin-CDK complex. Full article
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Article
Bioprospecting Red Sea Coastal Ecosystems for Culturable Microorganisms and Their Antimicrobial Potential
by Soha Al-Amoudi, Magbubah Essack, Marta F. Simões, Salim Bougouffa, Irina Soloviev, John A. C. Archer, Feras F. Lafi and Vladimir B. Bajic
Mar. Drugs 2016, 14(9), 165; https://doi.org/10.3390/md14090165 - 10 Sep 2016
Cited by 29 | Viewed by 9697
Abstract
Microorganisms that inhabit unchartered unique soil such as in the highly saline and hot Red Sea lagoons on the Saudi Arabian coastline, represent untapped sources of potentially new bioactive compounds. In this study, a culture-dependent approach was applied to three types of sediments: [...] Read more.
Microorganisms that inhabit unchartered unique soil such as in the highly saline and hot Red Sea lagoons on the Saudi Arabian coastline, represent untapped sources of potentially new bioactive compounds. In this study, a culture-dependent approach was applied to three types of sediments: mangrove mud (MN), microbial mat (MM), and barren soil (BS), collected from Rabigh harbor lagoon (RHL) and Al-Kharrar lagoon (AKL). The isolated bacteria were evaluated for their potential to produce bioactive compounds. The phylogenetic characterization of 251 bacterial isolates based on the 16S rRNA gene sequencing, supported their assignment to five different phyla: Proteobacteria, Firmicutes, Actinobacteria, Bacteroidetes, and Planctomycetes. Fifteen putative novel species were identified based on a 16S rRNA gene sequence similarity to other strain sequences in the NCBI database, being ≤98%. We demonstrate that 49 of the 251 isolates exhibit the potential to produce antimicrobial compounds. Additionally, at least one type of biosynthetic gene sequence, responsible for the synthesis of secondary metabolites, was recovered from 25 of the 49 isolates. Moreover, 10 of the isolates had a growth inhibition effect towards Staphylococcus aureus, Salmonella typhimurium and Pseudomonas syringae. We report the previously unknown antimicrobial activity of B. borstelensis, P. dendritiformis and M. salipaludis against all three indicator pathogens. Our study demonstrates the evidence of diverse cultured microbes associated with the Red Sea harbor/lagoon environments and their potential to produce antimicrobial compounds. Full article
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Article
Dichotocejpins A–C: New Diketopiperazines from a Deep-Sea-Derived Fungus Dichotomomyces cejpii FS110
by Zhen Fan, Zhang-Hua Sun, Zhong Liu, Yu-Chan Chen, Hong-Xin Liu, Hao-Hua Li and Wei-Min Zhang
Mar. Drugs 2016, 14(9), 164; https://doi.org/10.3390/md14090164 - 09 Sep 2016
Cited by 39 | Viewed by 6042
Abstract
Three new diketopiperazines, dichotocejpins A–C (13), together with eight known analogues (411), were isolated from the culture of the deep-sea sediment derived fungus Dichotomomyces cejpii FS110. Their structures, including absolute configurations, were elucidated by a [...] Read more.
Three new diketopiperazines, dichotocejpins A–C (13), together with eight known analogues (411), were isolated from the culture of the deep-sea sediment derived fungus Dichotomomyces cejpii FS110. Their structures, including absolute configurations, were elucidated by a combination of HRESIMS, NMR, X-ray crystallography, and ECD calculations. Compounds 46, 1011 showed significant cytotoxic activities against MCF-7, NCI-H460, HepG-2, and SF-268 tumor cell lines. Compound 1 exhibited excellent inhibitory activity against α-glucosidase with an IC50 of 138 μM. Full article
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Article
The Brown Alga Stypopodium zonale (Dictyotaceae): A Potential Source of Anti-Leishmania Drugs
by Deivid Costa Soares, Marcella Macedo Szlachta, Valéria Laneuville Teixeira, Angelica Ribeiro Soares and Elvira Maria Saraiva
Mar. Drugs 2016, 14(9), 163; https://doi.org/10.3390/md14090163 - 08 Sep 2016
Cited by 21 | Viewed by 5905
Abstract
This study evaluated the anti-Leishmania amazonensis activity of a lipophilic extract from the brown alga Stypopodium zonale and atomaric acid, its major compound. Our initial results revealed high inhibitory activity for intracellular amastigotes in a dose-dependent manner and an IC50 of [...] Read more.
This study evaluated the anti-Leishmania amazonensis activity of a lipophilic extract from the brown alga Stypopodium zonale and atomaric acid, its major compound. Our initial results revealed high inhibitory activity for intracellular amastigotes in a dose-dependent manner and an IC50 of 0.27 μg/mL. Due to its high anti-Leishmania activity and low toxicity toward host cells, we fractionated the lipophilic extract. A major meroditerpene in this extract, atomaric acid, and its methyl ester derivative, which was obtained by a methylation procedure, were identified by nuclear magnetic resonance (NMR) spectroscopy. Both compounds inhibited intracellular amastigotes, with IC50 values of 20.2 μM (9 μg/mL) and 22.9 μM (10 μg/mL), and selectivity indexes of 8.4 μM and 11.5 μM. The leishmanicidal activity of both meroditerpenes was independent of nitric oxide (NO) production, but the generation of reactive oxygen species (ROS) may be at least partially responsible for the amastigote killing. Our results suggest that the lipophilic extract of S. zonale may represent an important source of compounds for the development of anti-Leishmania drugs. Full article
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Article
A Saponification Method for Chlorophyll Removal from Microalgae Biomass as Oil Feedstock
by Tao Li, Jin Xu, Hualian Wu, Guanghua Wang, Shikun Dai, Jiewei Fan, Hui He and Wenzhou Xiang
Mar. Drugs 2016, 14(9), 162; https://doi.org/10.3390/md14090162 - 07 Sep 2016
Cited by 48 | Viewed by 12354
Abstract
Microalgae oil is an optimal feedstock for nutraceutical, pharmaceutical and biodiesel production, but its high levels of chlorophyll limit its large-scale application. To date, few effective approaches have been developed to remove chlorophyll from microalgae oil. The main purpose of this study was [...] Read more.
Microalgae oil is an optimal feedstock for nutraceutical, pharmaceutical and biodiesel production, but its high levels of chlorophyll limit its large-scale application. To date, few effective approaches have been developed to remove chlorophyll from microalgae oil. The main purpose of this study was to present a preprocessing method of algae oil feedstock (Scenedesmus) to remove chlorophyll by saponification. The results showed that 96% of chlorophyll in biomass was removed. High quality orange transparent oil could be extracted from the chlorophyll reduced biomass. Specifically, the proportion of neutral lipids and saturation levels of fatty acids increased, and the pigments composition became carotenoids-based. The critical parameters of chlorophyll reduced biodiesel conformed to the standards of the USA, China and EU. Sodium copper chlorophyllin could be prepared from the bleaching effluent. The results presented herein offer a useful pathway to improve the quality of microalgae oil and reduce the cost of microalgae biodiesel. Full article
(This article belongs to the Special Issue Advances and New Perspectives in Marine Biotechnology II 2016)
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Article
Design and Synthesis of Analogues of Marine Natural Product Galaxamide, an N-methylated Cyclic Pentapeptide, as Potential Anti-Tumor Agent in Vitro
by Jignesh Lunagariya, Shenghui Zhong, Jianwei Chen, Defa Bai, Poonam Bhadja, Weili Long, Xiaojian Liao, Xiaoli Tang and Shihai Xu
Mar. Drugs 2016, 14(9), 161; https://doi.org/10.3390/md14090161 - 03 Sep 2016
Cited by 8 | Viewed by 6929
Abstract
Herein, we report design and synthesis of novel 26 galaxamide analogues with N-methylated cyclo-pentapeptide, and their in vitro anti-tumor activity towards the panel of human tumor cell line, such as, A549, A549/DPP, HepG2 and SMMC-7721 using MTT assay. We have also investigated [...] Read more.
Herein, we report design and synthesis of novel 26 galaxamide analogues with N-methylated cyclo-pentapeptide, and their in vitro anti-tumor activity towards the panel of human tumor cell line, such as, A549, A549/DPP, HepG2 and SMMC-7721 using MTT assay. We have also investigated the effect of galaxamide and its representative analogues on growth, cell-cycle phases, and induction of apoptosis in SMMC-7721 cells in vitro. Reckon with the significance of conformational space and N-Me aminoacid (aa) comprising this compound template, we designed the analogues with modification in N-Me-aa position, change in aa configuration from l to d aa and substitute one Leu-aa to d/l Phe-aa residue with respective to the parent structure. The efficient solid phase parallel synthesis approach is employed for the linear pentapeptide residue containing N-Me aa, followed by solution phase macrocyclisation to afford target cyclo pentapeptide compounds. In the present study, all galaxamide analogues exhibited growth inhibition in A549, A549/DPP, SMMC-7721 and HepG2 cell lines. Compounds 6, 18, and 22 exhibited interesting activities towards all cell line tested, while Compounds 1, 4, 15, and 22 showed strong activity towards SMMC-7221 cell line in the range of 1–2 μg/mL IC50. Flow cytometry experiment revealed that galaxamide analogues namely Compounds 6, 18, and 22 induced concentration dependent SMMC-7721 cell apoptosis after 48 h. These compounds induced G0/G1 phase cell-cycle arrest and morphological changes indicating induction of apoptosis. Thus, findings of our study suggest that the galaxamide and its analogues 6, 18 and 22 exerted growth inhibitory effect on SMMC-7721 cells by arresting the cell cycle in the G0/G1 phase and inducing apoptosis. Compound 1 showed promising anti-tumor activity towards SMMC-7721 cancer cell line, which is 9 and 10 fold higher than galaxamide and reference DPP (cisplatin), respectively. Full article
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Article
A Coral-Derived Compound Improves Functional Recovery after Spinal Cord Injury through Its Antiapoptotic and Anti-Inflammatory Effects
by Chun-Hong Chen, Nan-Fu Chen, Chien-Wei Feng, Shu-Yu Cheng, Han-Chun Hung, Kuan-Hao Tsui, Chi-Hsin Hsu, Ping-Jyun Sung, Wu-Fu Chen and Zhi-Hong Wen
Mar. Drugs 2016, 14(9), 160; https://doi.org/10.3390/md14090160 - 02 Sep 2016
Cited by 26 | Viewed by 8703
Abstract
Background: Our previous in vitro results demonstrated that 11-dehydrosinulariolide significantly reduced 6-hydroxydopamine-induced cytotoxicity and apoptosis in a human neuroblastoma cell line, SH-SY5Y, and suppressed the expression of inducible NO synthase (iNOS) and cyclooxygenase 2 in lipopolysaccharide-stimulated macrophage cells. The neuroprotective and anti-inflammatory effects [...] Read more.
Background: Our previous in vitro results demonstrated that 11-dehydrosinulariolide significantly reduced 6-hydroxydopamine-induced cytotoxicity and apoptosis in a human neuroblastoma cell line, SH-SY5Y, and suppressed the expression of inducible NO synthase (iNOS) and cyclooxygenase 2 in lipopolysaccharide-stimulated macrophage cells. The neuroprotective and anti-inflammatory effects of 11-dehydrosinulariolide may be suitable for treating spinal cord injury (SCI). Methods: In the present study, Wistar rats were pretreated with 11-dehydrosinulariolide or saline through intrathecal injection after a thoracic spinal cord contusion injury induced using a New York University (NYU) impactor. The apoptotic cells were assessed using the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The expression and localization of proinflammatory, apoptosis-associated and cell survival-related pathway proteins were examined through immunoblotting and immunohistochemistry. Results: 11-Dehydrosinulariolide attenuated SCI-induced cell apoptosis by upregulating the antiapoptotic protein Bcl-2 and cell survival-related pathway proteins p-Akt and p-ERK, 8 h after SCI. Furthermore, the transcription factor p-CREB, which regulates Bcl-2 expression, was upregulated after 11-dehydrosinulariolide treatment. On day 7 after SCI, 11-dehydrosinulariolide exhibited an anti-inflammatory effect, attenuating SCI-induced upregulation of the inflammatory proteins iNOS and tumor necrosis factor-α. 11-Dehydrosinulariolide also induced an increase in the expression of arginase-1 and CD206, markers of M2 microglia, in the injured spinal cord on day 7 after SCI. Thus, the anti-inflammatory effect of 11-dehydrosinulariolide may be related to the promotion of an alternative pathway of microglia activation. Conclusion: The results show that 11-dehydrosinulariolide exerts antiapoptotic effects at 8 h after SCI and anti-inflammatory effects at 7 days after SCI. We consider that this compound may be a promising therapeutic agent for SCI. Full article
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Review
Antimicrobial Compounds from Eukaryotic Microalgae against Human Pathogens and Diseases in Aquaculture
by Charlotte Falaise, Cyrille François, Marie-Agnès Travers, Benjamin Morga, Joël Haure, Réjean Tremblay, François Turcotte, Pamela Pasetto, Romain Gastineau, Yann Hardivillier, Vincent Leignel and Jean-Luc Mouget
Mar. Drugs 2016, 14(9), 159; https://doi.org/10.3390/md14090159 - 02 Sep 2016
Cited by 165 | Viewed by 14466
Abstract
The search for novel compounds of marine origin has increased in the last decades for their application in various areas such as pharmaceutical, human or animal nutrition, cosmetics or bioenergy. In this context of blue technology development, microalgae are of particular interest due [...] Read more.
The search for novel compounds of marine origin has increased in the last decades for their application in various areas such as pharmaceutical, human or animal nutrition, cosmetics or bioenergy. In this context of blue technology development, microalgae are of particular interest due to their immense biodiversity and their relatively simple growth needs. In this review, we discuss about the promising use of microalgae and microalgal compounds as sources of natural antibiotics against human pathogens but also about their potential to limit microbial infections in aquaculture. An alternative to conventional antibiotics is needed as the microbial resistance to these drugs is increasing in humans and animals. Furthermore, using natural antibiotics for livestock could meet the consumer demand to avoid chemicals in food, would support a sustainable aquaculture and present the advantage of being environmentally friendly. Using natural and renewable microalgal compounds is still in its early days, but considering the important research development and rapid improvement in culture, extraction and purification processes, the valorization of microalgae will surely extend in the future. Full article
(This article belongs to the Collection Bioactive Compounds from Marine Plankton)
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Article
Hierridin B Isolated from a Marine Cyanobacterium Alters VDAC1, Mitochondrial Activity, and Cell Cycle Genes on HT-29 Colon Adenocarcinoma Cells
by Sara Freitas, Rosário Martins, Margarida Costa, Pedro N. Leão, Rui Vitorino, Vitor Vasconcelos and Ralph Urbatzka
Mar. Drugs 2016, 14(9), 158; https://doi.org/10.3390/md14090158 - 31 Aug 2016
Cited by 30 | Viewed by 6660
Abstract
Background: Hierridin B was isolated from a marine cyanobacterium Cyanobium sp. strain and induced cytotoxicity selectively in HT-29 adenocarcinoma cells. The underlying molecular mechanism was not yet elucidated. Methods: HT-29 cells were exposed to the IC50 concentration of hierridin B (100.2 μM) [...] Read more.
Background: Hierridin B was isolated from a marine cyanobacterium Cyanobium sp. strain and induced cytotoxicity selectively in HT-29 adenocarcinoma cells. The underlying molecular mechanism was not yet elucidated. Methods: HT-29 cells were exposed to the IC50 concentration of hierridin B (100.2 μM) for 48 h. Non-targeted proteomics was performed using 2D gel electrophoresis and MALDI-TOF/TOF mass spectrometry. The mRNA expression of apoptotic and cell cycle genes were analyzed by real-time PCR. Automated quantification of 160 cytoplasm and mitochondrial parameter was done by fluorescence microscopy using CellProfiler software. Results: Proteomics identified 21 significant different proteins, which belonged to protein folding/synthesis and cell structure amongst others. Increase of VDAC1 protein responsible for formation of mitochondrial channels was confirmed by mRNA expression. A 10-fold decrease of cytoskeleton proteins (STMN1, TBCA) provided a link to alterations of the cell cycle. CCNB1 and CCNE mRNA were decreased two-fold, and P21CIP increased 10-fold, indicative of cell cycle arrest. Morphological analysis of mitochondrial parameter confirmed a reduced mitochondrial activity. Conclusion: Hierridin B is a potential anticancer compound that targets mitochondrial activity and function. Full article
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Article
Additional New Cytotoxic Triquinane-Type Sesquiterpenoids Chondrosterins K–M from the Marine Fungus Chondrostereum sp.
by Lei Huang, Wen-Jian Lan, Rong Deng, Gong-Kan Feng, Qing-Yan Xu, Zhi-Yu Hu, Xiao-Feng Zhu and Hou-Jin Li
Mar. Drugs 2016, 14(9), 157; https://doi.org/10.3390/md14090157 - 26 Aug 2016
Cited by 19 | Viewed by 5849
Abstract
By the method of 1H NMR prescreening and tracing the diagnostic proton signals of the methyl groups, three additional new triquinane-type sesquiterpenoids—chondrosterins K–M (13) and the known sesquiterpenoid anhydroarthrosporone (4)—were isolated from the marine fungus Chondrostereum [...] Read more.
By the method of 1H NMR prescreening and tracing the diagnostic proton signals of the methyl groups, three additional new triquinane-type sesquiterpenoids—chondrosterins K–M (13) and the known sesquiterpenoid anhydroarthrosporone (4)—were isolated from the marine fungus Chondrostereum sp. Their structures were elucidated on the basis of MS, 1D, and 2D NMR data. Chondrosterin K is a rare hirsutane sesquiterpenoid, in which a methyl group was migrated from C-2 to C-6 and has a double bond between C-2 and C-3. Compounds 13 showed significant cytotoxicities against various cancer cell lines in vitro. Full article
(This article belongs to the Special Issue Marine Fungal Natural Products)
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