The goal of this study was to examine the ameliorative effects of black ginseng(BG) in male obese diabetic C57BLKS/ J-db/db mice. Ten-week-old male db/db mice were administrated 300 ㎎/㎏ of F-BG daily for 6 weeks, The db/db mice where corresponded to the normal group and db/db mice which were the diabetic positive group were not provided BG treatment. The supressive effects of treatment were examined on serum lipids levels, which included total cholesterol, triglyceride, LDL-cholesterol and nonesterified fatty acid. Also, weight changes and the relative weight of liver and kidney, organ pathological investigation were measured. The effects of treatment were assessed by comparing the results of the db/db mice that received BG for 6 weeks with that of the diabetic positive group. Significant differences in several biological parameters such as HDL level(p<0.05), TG level(p<0.05) and NEFA level(p<0.05) were observed for the BG group. BG treatment increased the HDL level and decreased the NEFA level, which could ameliorate hyperlipidemia or blood circulation.

Hyperglycemia found in diabetes mellitus causes several physiological abnormalities including the formation of advanced glycation end products (AGEs) and oxidative stress. Accumulation of AGEs and elevation of oxidative stress plays major roles in the development of diabetic complications. Adiponectin secreted from adipocytes is known to improve insulin sensitivity and blood glucose level. Curcumin (CCM), a bioactive component of turmeric, has been reported as a potent antioxidant. Present work aimed to elucidate the roles of CCM in high glucose-induced protein glycation and intracellular events in mature adipocytes. The results demonstrated that CCM inhibited the formation of fluorescent AGEs by approximated 52% at 3 weeks of bovine serum albumin (BSA) glycation with glucose. Correspondingly, CCM decreased the levels of fructosamine and α-dicarbonyl compounds during BSA glycation with glucose. These data suggested that CCM might be a new promising anti-glycation agent. Also, CCM reduced high glucose-induced oxidative stress in a dose dependent manner, whereas CCM treatment time-dependently elevated the expression of adiponectin gene in 3T3-L1 adipocytes. The findings from this study suggested the possibility of therapeutic use of CCM for the prevention of diabetic complications and obesity-related diseases.

Background : ROS produced by oxidative stress damaged endothelial cells, and cause a variety of vascular complications. In diabetic hyperglycemia state, ROS increase. The polyol pathway occur in diabetic complications, the excess glucose is absorbed into the polyol pathway when aldose reductase increased, NADPH changes it to sorbitol. Glutathione (GSH) removes ROS. GSH level is reduced by glutathione reductase, using NADPH as an electron donor. Activation of the polyol pathway decrease NADPH, and GSH also reduced. As a result, ROS is increased. In diabetic hyperglycemia state, Glycolysis increases. Effects of increased glycolysis, protein kinase C (PKC) is increased. NAD(P)H oxidase, stimulated by PKC-dependent pathway, increases ROS in the cell. In this study, we measured the ROS scavenging activity of 5 natural products (Lycii fructus, Astragalus membranaceus, Cassia Tora, Polygonatum odoratum, Rubus Coreanus), to confirm the efficacy as diabetic antioxidants. Methods and Results : We extracted 5 natural product by distilled water and ethanol. DPPH radical scavenging activity was significantly higher in Lycii fructus, Rubus coreanus. ABTS radical scavenging activity was better Rubus coreanus, Lycii fructus, Cassia Tora. In addition to, Rubus coreanus, Cassia Tora, Lycii fructus was comparatively higher reducing power activity than other natural products. And total phenolic and flavonoid contents were much higher in Rubus coreanus compared with other extracts. Conclusion : These results suggest that Lycii fructus, Rubus coreanus can be applied as diabetic antioxidant that prevent vascular complications caused by ROS.