title: Octaphlorethol A, a novel phenolic compound isolated from Ishige foliacea, protects against streptozotocin-induced pancreatic β cell damage by reducing oxidative stress and apoptosis.
abstract: Pancreatic β cells are extremely sensitive to oxidative stress, which probably has an important role in β cell damage in diabetes. The protective effect of octaphlorethol A (OPA), a novel phenolic compound isolated from Ishige foliacea, against streptozotocin (STZ)-induced pancreatic β cell damage was investigated using a rat insulinoma cell line (RINm5F pancreatic β cells). Pretreatment with OPA decreased the death of STZ-treated pancreatic β cells at concentrations of 12.5 μg/ml or 50 μg/ml, and reduced the generation of thiobarbituric acid reactive substances and intracellular reactive oxygen species in a dose-dependent manner in STZ-treated pancreatic β cells. In addition, the OPA pretreatment increased the activities of antioxidant enzymes such as catalase, superoxide dismutase, and glutathione peroxidase in STZ-treated pancreatic β cells. Moreover, OPA treatment elevated the level of insulin, which was reduced by STZ treatment, and protected pancreatic β cells against damage under STZ-treated conditions. These effects were mediated by suppressing apoptosis and were associated with increased anti-apoptotic Bcl-xL expression and reduced pro-apoptotic Bax and cleaved caspase-3 expression. These findings indicate that OPA may be useful as a potential pharmaceutical agent to protect against pancreatic β cell damage caused by oxidative stress associated with diabetes.
authors.affiliation: Division of Food Bioscience, Konkuk University, Chungju Chungbuk 380-701, Republic of Korea.
authors.forename: Seung-Hong
authors.initials: SH
authors.lastname: Lee
authors.forename: Sung-Myung
authors.initials: SM
authors.lastname: Kang
authors.forename: Seok-Chun
authors.initials: SC
authors.lastname: Ko
authors.forename: Min-Cheol
authors.initials: MC
authors.lastname: Kang
authors.forename: You-Jin
authors.initials: YJ
authors.lastname: Jeon
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000302:isolation & purification / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D051017:Apoptosis Regulatory Proteins / Q000819:agonists / Q000037:antagonists & inhibitors / Q000378:metabolism; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D007004:Hypoglycemic Agents / Q000302:isolation & purification / Q000494:pharmacology*; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D050417:Insulin-Secreting Cells / Q000187:drug effects* / Q000378:metabolism; D009994:Osmolar Concentration; D016877:Oxidants / Q000037:antagonists & inhibitors / Q000633:toxicity; D018384:Oxidative Stress / Q000187:drug effects*; D010088:Oxidoreductases / Q000737:chemistry / Q000378:metabolism; D010140:Pacific Ocean; D000459:Phaeophyceae / Q000737:chemistry* / Q000254:growth & development; D010636:Phenols / Q000302:isolation & purification / Q000494:pharmacology*; D051381:Rats; D017382:Reactive Oxygen Species / Q000037:antagonists & inhibitors / Q000378:metabolism; D056910:Republic of Korea; D013311:Streptozocin / Q000037:antagonists & inhibitors / Q000633:toxicity
chemical_list: D000975:Antioxidants; D051017:Apoptosis Regulatory Proteins; D007004:Hypoglycemic Agents; D007328:Insulin; D016877:Oxidants; D010636:Phenols; D017382:Reactive Oxygen Species; C572462:octaphlorethol A; D013311:Streptozocin; D010088:Oxidoreductases
keywords: Apoptosis; Octaphlorethol A; Oxidative stress; Pancreatic β cells; Protective effect