title: Renal peroxidative changes mediated by oxalate: the protective role of fucoidan.
abstract: Oxalate, one of the major constituents of renal stones is known to induce free radicals which damage the renal membrane. Damaged epithelia might act as nidi for stone formation aggravating calcium oxalate precipitation during hyperoxaluria. In the present study, the beneficial effects of fucoidan on oxalate-induced free radical injury were investigated. Male Wistar rats were divided into four groups. Hyperoxaluria was induced in two groups by administration of 0.75% ethylene glycol in drinking water for 28 days and one of them was treated with fucoidan from Fucus vesiculosus at a dose of 5 mg/kg b.wt subcutaneously commencing from the 8th day of induction. A control and drug control (fucoidan alone) was also included in the study. The extent of renal injury in hyperoxaluria was evident from the increased activities of alkaline phosphatase, gamma-glutamyl transferase, beta-glucuronidase, N-acetyl-beta-D-glucosaminidase in urine. There was a positive correlation between plasma malondialdehyde levels and renal membrane damage indicating a striking relation between free radical formation and cellular injury. Increased protein carbonyl and decreased thiols further exemplified the oxidative milieu prevailing during hyperoxaluria. Decreased renal membrane ATPases accentuated the renal membrane damage induced by oxalate. Renal microscopic analysis showed abnormal findings in histology as an evidence of oxalate damage. The above biochemical and histopathological discrepancies were abrogated with fucoidan administration, indicating its protective role in oxalate mediated peroxidative injury.
authors.affiliation: Department of Medical Biochemistry, Dr ALM Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Chennai, India.
authors.forename: Coothan Kandaswamy
authors.initials: CK
authors.lastname: Veena
authors.forename: Anthony
authors.initials: A
authors.lastname: Josephine
authors.forename: Sreenivasan P
authors.initials: SP
authors.lastname: Preetha
authors.forename: Palaninathan
authors.initials: P
authors.lastname: Varalakshmi
authors.forename: Rajaguru
authors.initials: R
authors.lastname: Sundarapandiyan
mesh_terms: D000818:Animals; D002129:Calcium Oxalate / Q000378:metabolism*; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D004195:Disease Models, Animal; D006959:Hyperoxaluria / Q000378:metabolism / Q000517:prevention & control*; D007668:Kidney / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D015227:Lipid Peroxidation / Q000187:drug effects*; D008054:Lipid Peroxides / Q000097:blood; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D011134:Polysaccharides / Q000008:administration & dosage / Q000627:therapeutic use*; D020011:Protective Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D050050:Protein Carbonylation / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D013438:Sulfhydryl Compounds / Q000378:metabolism
chemical_list: D008054:Lipid Peroxides; D011134:Polysaccharides; D020011:Protective Agents; D013438:Sulfhydryl Compounds; D002129:Calcium Oxalate; D008315:Malondialdehyde; C007789:fucoidan