Hypolipidaemic and antioxidative effects of oligonol, a low-molecular-weight polyphenol derived from lychee fruit, on renal damage in type 2 diabetic mice.
Oligonol was orally administered at 10 or 20 mg/kg body weight per d for 8 weeks to db/db mice with type 2 diabetes, and its effects were compared with those of the vehicle in db/db and m/m (misty, non-diabetic) mice. Serum and renal biochemical factors, protein expressions related to lipid metabolism and inflammation, and advanced glycation endproducts were measured. There were significant reductions in the serum lipid concentration, reactive oxygen species (ROS) and lipid peroxidation, as well as improvements in renal function parameters. In addition, oligonol treatment significantly decreased ROS levels and lipid peroxidation in the kidney. In particular, the renal lipid contents such as TAG and total cholesterol were significantly reduced in the oligonol-administered groups through the up-regulation of PPARα and down-regulation of sterol regulatory element-binding protein-1 in db/db mice. Moreover, oligonol inhibited non-fluorescent AGE formation and their receptor expression, suggesting that it could effectively inhibit AGE development caused by oxidative stress and/or dyslipidaemia in the kidney of db/db mice. Furthermore, augmented expressions of NF-κBp65, cyclo-oxygenase-2 and inducible NO synthase were down-regulated to the levels of m/m mice in the group given oligonol at 20 mg/kg. This means that oligonol would act as a regulator in the inflammatory response of type 2 diabetes. The present results suggest that oligonol could have renoprotective effects against abnormal lipid metabolism and ROS-related AGE formation in type 2 diabetes.
Noh
Jeong Sook
JS
Institute of Natural Medicine, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan.
Kim
Hyun Young
HY
Park
Chan Hum
CH
Fujii
Hajime
H
Yokozawa
Takako
T
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology / Q000627:therapeutic use*; D015415:Biomarkers; D002392:Catechin / Q000031:analogs & derivatives* / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use; D048909:Diabetes Complications / Q000517:prevention & control; D003921:Diabetes Mellitus, Experimental / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000097:blood*; D005638:Fruit / Q000737:chemistry; D017127:Glycation End Products, Advanced / Q000378:metabolism; D006949:Hyperlipidemias / Q000188:drug therapy*; D000960:Hypolipidemic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D007668:Kidney / Q000187:drug effects / Q000473:pathology; D007674:Kidney Diseases / Q000209:etiology / Q000517:prevention & control; D032125:Litchi / Q000737:chemistry*; D008297:Male; D051379:Mice; D009929:Organ Size; D018384:Oxidative Stress; D010636:Phenols / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use*; D017382:Reactive Oxygen Species; D017392:Thiobarbituric Acid Reactive Substances
D000975:Antioxidants; D015415:Biomarkers; D017127:Glycation End Products, Advanced; D000960:Hypolipidemic Agents; D010636:Phenols; D017382:Reactive Oxygen Species; D017392:Thiobarbituric Acid Reactive Substances; C514283:oligonol; D002392:Catechin