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Abstract: The aim of this study was to investigate the antioxidant and anti-inflammatory activities of aminoethyl-chitooligosaccharides (AE-COS) in murine microglial cells (BV-2). At the high concentration of 100μg/ml, the inhibition of reactive oxygen species, DNA, protein and lipid oxidation were determined in BV-2 cells, at the rates of 77%, 80%, 85% and 85%, respectively. Furthermore, AE-COS was studied for its capabilities against lipopolysaccharide-induced inflammatory responses in BV-2 cells. It was found that AE-COS reduced the level of nitric oxide (NO) and prostaglandin E2 production by diminishing the expression of inducible NO synthase and cyclooxygenase-2 without significant cytotoxicity. Moreover, the inhibitory activities of AE-COS on generation of tumor necrosis factor-alpha and interleukin-1beta were performed. Collectively, these results indicate that AE-COS possess potential antioxidant and anti-inflammatory activities in brain microglia, and could be a useful therapeutic agent for the treatment of neuroinflammatory diseases. [Copyright &y& Elsevier]

Abstract: The purpose of this research is not only to produce two kinds of chitin oligosaccharides or N-acetyl chito-oligosaccharides (NA-COSs) with different molecular weights (MW) from crab chitin hydrolysis solution but also to determine their effect against oxidative stress in live cells. Two kinds of NA-COSs with MW 1–3kDa (NA-COS 1–3kDa) and below 1kDa (NA-COS<1kDa) were obtained using an ultrafiltration membrane system. They exhibited an inhibitory effect against DNA and protein oxidation. In addition, in their presence, intracellular glutathione (GSH) level and direct intracellular radical scavenging effect were significantly increased in a time-dependent manner in mouse macrophages (RAW 264.7) and rendered inhibitory effect against cellular oxidative stress. In particular, NA-COS 1–3kDa was more effective than NA-COS<1kDa in protein oxidation and production of intracellular free radicals in live cells. These results suggest that NA-COSs act as a potential scavenger against oxidative stress in cells. [Copyright &y& Elsevier]

Abstract: The aim of this research is to identify the cellular antioxidant effects of chitin oligosaccharides (NA-COS; M w 229.21–593.12Da) produced by acidic hydrolysis of crab chitin. The inhibitory effect of NA-COS on myeloperoxidase (MPO) activity in human myeloid cells (HL-60) and oxidation of DNA and protein in mouse macrophages (Raw 264.7) were identified. Furthermore, their direct radical scavenging effect by 2′,7′-dichlorofluorescein (DCF) intensity and intracellular glutathione (GSH) level were significantly increased in a time dependent manner, respectively. These results suggest that NA-COS act as a potent antioxidant in live cells. [Copyright &y& Elsevier]

Abstract: Marine organisms have been recognized as rich sources of bioactive compounds with valuable nutraceutical and pharmaceutical potentials. Recently, marine bioactive peptides have gained much attention because of their numerous health beneficial effects. Notably, these peptides exhibit various biological activities such as antioxidant, anti-hypertensive, anti-human immunodeficiency virus, anti-proliferative, anticoagulant, calcium-binding, anti-obesity and anti-diabetic activities. This review mainly presents biological activities of peptides from marine organisms and emphasizing their potential applications in foods as well as pharmaceutical areas. [Copyright &y& Elsevier]

Abstract: This study explains the novel possibility of the involvement of gallic acid conjugated chitooligosaccharides (G-COS) in ameliorating cellular antioxidant activity. The free radicals scavenging activity of G-COS was assessed by using an electron spin resonance technique. In addition, the inhibition of reactive oxygen species, lipid, protein, and DNA oxidation were determined in human chondrosarcoma (SW1353 cells). Moreover, the antioxidative mechanism of G-COS was evaluated by protein and gene expression levels of antioxidant enzymes (superoxide dismutase and glutathione). Western blot analysis revealed that G-COS inhibit radical-mediated expression and activation of NF-κB proteins (transcription factor in the regulation of expression of numerous genes in the setting of the osteoarthritic response). Based on the results of this study, G-COS can be used as a scavenger in controlling free radicals that lead to damage to cellular systems in osteoarthritis. [Copyright &y& Elsevier]

Highlights: [•] Intracellular free radicals scavenging activities of 4-hydroxybenzyl-chitooligomers (HB-COS) were determined in Chang liver cells. [•] HB-COS exerted protective effects against reactive oxygen species and DNA oxidation. [•] HB-COS increased the gene and protein expressions of intracellular antioxidant enzymes. [•] Antioxidant effects are due to suppression of NF-κB signaling pathway. [•] Collectively, HB-COS can be used as a free radicals scavenger in cellular system. [ABSTRACT FROM AUTHOR]

Abstract: In this research, a novel derivative of chitooligosaccharides (COS) was synthesized by covalently linking gallic acid and COS (gallate-COS) via carbodiimide to improve cellular antioxidant activity. The direct intracellular radical scavenging effect of gallate-COS by 2′,7′-dichlorofluorescin diacetate (DCFH-DA) method, and the inhibition of oxidation of cellular macromolecules, such as DNA, protein and lipid in mouse macrophages (RAW264.7 cells) were determined. Furthermore, with the treatment of gallate-COS, the expression levels of antioxidant enzymes such as superoxide dismutase (SOD) and glutathione (GSH) were significantly increased according to reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis. In addition, gallate-COS decreased reactive oxygen species induced activation of the nuclear transcription factor (NF-κB). Collectively, these results suggest that gallate-COS can be used as a potential natural compound-based antioxidant in the functional food and pharmaceutical industries. [Copyright &y& Elsevier]