Effect of sulfated galactan from Porphyra haitanensis on H2O2-induced premature senescence in WI-38 cells

Porphyran sulfated galactan extracted from red algae Porphyra haitanensis is a sulfated polysaccharide, which possesses excellent activities. In the present study, WI-38 cells were treated with H2O2 to induce premature senescence and then the protection of porphyran against aging in vitro and associated molecular mechanisms were investigated. The protection occurred in a dose-dependent manner, offering an optimal efficacy starting at 10 mu g/mL. The proportion of SA-beta-gal positive cells in porphyran group decreases from 53% to 23% in the cultures at 30 PDs. Porphyran has been detected specifically reducing SAHF-like foci formation in senescent cells. In addition, porphyran significantly affected the p53-p21 pathways in H2O2-treated WI-38 cells. Our data suggest the promising role of porphyran as an attractive and bio-safe agent with the potential to retard senescence and attenuate senescence-related diseases. (C) 2017 Published by Elsevier B.V.