Attenuation of hydrogenperoxide-induced oxidative damages in L929 fibroblast cells by sulfated polysaccharides isolated from the edible marine algae Padina tetrastromatica

Sulfated polysaccharides are polymers with potent biological roles such as antioxidant, anticancer, anti-inflammatory, and immunomodulatory activities. They are gaining significance in advanced healthcare research, since they can control oxidative cellular damages by arresting the reactive oxygen species. Hence, this study aims to evaluate the cellular antioxidant potential of sulfated polysaccharides isolated from the marine algae Padina tetrastromatica in L929 cells. The monosaccharide composition of sulfated polysaccharides was determined using high-performance liquid chromatography. The protective effect of sulfated polysaccharides on L929 fibroblast cells under H2O2-induced oxidative stress has been evaluated using MTT assay, acridine orange/ethidium bromide staining, flow cytometry, comet assay, DCFH-DA staining, fluorometry, and biochemical assays. Sulfated polysaccharides were found to contain glucose, fucose, xylose, and uronic acid. It was non-toxic to L929 cells and effectively increased the viability of mouse fibroblast cells under induced oxidative stress. Various cellular damages such as apoptosis, plasma membrane alterations, DNA damage, and lipid peroxidation induced by H2O2 have been attenuated by sulfated polysaccharides. This might be due to the reduction of intracellular reactive oxygen species level by sulfated polysaccharides as observed in DCFH-DA staining. Sulfated polysaccharides improved the activity of intracellular antioxidant status and glutathione system. The augmentation of endogenous antioxidant enzymes and glutathione system by sulfated polysaccharides can be the possible reason for the reduction of intracellular reactive oxygen species, prevention of apoptosis, and betterment of viability in L929 cells. The study confirms the potent antioxidant activity of the sulfated polysaccharides in addition to their structural and nutritional roles.