Antioxidant Fucoidans Obtained from Tropical Seaweed Protect Pre-Osteoblastic Cells from Hydrogen Peroxide-Induced Damage.
Some antioxidant compounds decrease the amount of intracellular reactive oxygen species (ROS) and consequently reduce the deleterious effects of ROS in osteoblasts. Thus, these compounds fight against osteoporosis. Brown seaweeds are a rich source of antioxidant fucose-containing sulfated polysaccharides (fucans and fucoidans). We obtained six fucoidans (FRFs)-F0.3, F0.5, F0.7, F1.0, F1.5, and F2.1-from Dictyota mertensii by proteolytic digestion followed by sequential acetone precipitation. Except for F0.3, all FRFs showed antioxidant activity in different in vitro tests. In pre- osteoblast-like cells (MC3T3-L1) exposed to H2O2-oxidative stress, caspase-3 and caspase-9 were activated, resulting in apoptosis of the cells. We also observed a decrease in superoxide dismutase (SOD) and alkaline phosphatase (ALP) activity. The antioxidant FRFs protected the cells from the oxidative damage caused by H2O2, decreasing intracellular ROS and caspase activation, and increasing SOD activity. The most effective protection against damage was provided by F0.7, F1.5, and F2.1. At 0.5 mg/mL, these FRFs also suppressed the H2O2-mediated inhibition of ALP activity. The data indicated that FRFs F0.7, F1.5, and F2.1 from D. mertensii were antioxidants that protected bone tissue from oxidative stress and could represent possible adjuvants for the treatment of bone fragility through counteracting oxidative phenomena.
['Fidelis|Gabriel Pereira|GP|0000-0003-1974-3771', 'Silva|Cynthia Haynara Ferreira|CHF|', 'Nobre|Leonardo Thiago Duarte Barreto|LTDB|0000-0002-4728-8035', 'Medeiros|Valquíria Pereira|VP|0000-0002-9378-6481', 'Rocha|Hugo Alexandre Oliveira|HAO|0000-0003-2252-1221', 'Costa|Leandro Silva|LS|']
D016475:3T3 Cells D000818:Animals D017209:Apoptosis D002454:Cell Differentiation D016166:Free Radical Scavengers D006801:Humans D006861:Hydrogen Peroxide D051379:Mice D010006:Osteoblasts D010024:Osteoporosis D010084:Oxidation-Reduction D018384:Oxidative Stress D000459:Phaeophyta D011134:Polysaccharides D012624:Seaweed
osteoporosis brown seaweed sulfated polysaccharides oxidative damage bone cells