title: Ulcer preventive and antioxidative properties of astaxanthin from Haematococcus pluvialis.
abstract: The anti-ulcer properties of astaxanthin fractions such as total carotenoid and astaxanthin esters from Haematococcus pluvialis were evaluated in ethanol-induced gastric ulcers in rats. Since oxygen radical release is a pathogenic factor of ethanol-induced gastric damage, astaxanthin - a free radical scavenger, was investigated as a potential ulcer preventive agent. Astaxanthin fractions - total carotenoid and astaxanthin esters were orally administered to experimental rats at 100, 250 and 500 microg/kg b.w. prior to ulcer induction. Alcian blue binding assay indicates that, total carotenoid and astaxanthin esters at 500 microg/kg b.w could protect gastric mucin approximately 40% and 67% respectively. Pre-treatment with astaxanthin esters, also resulted in significant increase in antioxidant enzyme levels - catalase, superoxide dismutase, and glutathione peroxidase in stomach homogenate. Histopathological examination substantiated the protective effect of astaxanthin in pre-treated rats. The increased antioxidant potencies such as free radical scavenging activity with an IC(50) of approximately 8 microg/ml and reducing power abilities (59 x 10(3) U/g) in vitro, reveal that H. pluvialis astaxanthin may protect gastric mucosal injury by antioxidative mechanism. In addition, approximately 23 fold increased lipoxygenase-inhibitory property, in comparison with standard astaxanthin and significant H(+), K(+)-ATPase-inhibitory activity of astaxanthin esters, in comparison with known proton pump blocking anti-ulcer drug - omeprazole, may envisage the potential gastroprotective effect by regulating the gastric mucosal injury and gastric acid secretion by the gastric cell during ulcer disease.
authors.affiliation: Plant Cell Biotechnology Department, Central Food Technological Research Institute, Mysore, 570 020, India.
authors.forename: Burde Sandesh
authors.initials: BS
authors.lastname: Kamath
authors.forename: Belagihally Manjegowda
authors.initials: BM
authors.lastname: Srikanta
authors.forename: Shylaja Mallaiah
authors.initials: SM
authors.lastname: Dharmesh
authors.forename: Ravi
authors.initials: R
authors.lastname: Sarada
authors.forename: Gokare Aswathanarayana
authors.initials: GA
authors.lastname: Ravishankar
mesh_terms: D000818:Animals; D000897:Anti-Ulcer Agents / Q000494:pharmacology*; D000975:Antioxidants / Q000494:pharmacology*; D002338:Carotenoids / Q000302:isolation & purification / Q000494:pharmacology; D000460:Chlorophyta / Q000737:chemistry*; D005260:Female; D005753:Gastric Mucosa / Q000473:pathology; D015227:Lipid Peroxidation / Q000187:drug effects; D016859:Lipoxygenase Inhibitors / Q000494:pharmacology; D008297:Male; D054328:Proton Pump Inhibitors; D051381:Rats; D017208:Rats, Wistar; D013276:Stomach Ulcer / Q000517:prevention & control; D024341:Xanthophylls / Q000302:isolation & purification / Q000494:pharmacology
chemical_list: D000897:Anti-Ulcer Agents; D000975:Antioxidants; D016859:Lipoxygenase Inhibitors; D054328:Proton Pump Inhibitors; D024341:Xanthophylls; D002338:Carotenoids; C005948:astaxanthine