Effect Of RVisfatin On Human Adipocytes

The prevalence of obesity and diabetes has increased rapidly. They are increasingly seen as a public health problem requiring concerted action. They are both polygene multifactorial chronic metabolic diseases caused by multiple factors such as heredity and environment. Existing researches showed that insulin resistance was the central link of multiple metabolic disorders related to obesity. It was also collective morbidity base of obesity and type 2 diabetes. So it is a key point of the treatment of obesity and type 2 diabetes to improve insulin resistance. Adiponectin, which was discovered recently, plays a critical role in improvement of insulin resistance, as unique adipocytokine to have protection on human body. Adiponectin and its receptors have tight relativity with insulin sensitivity, and it will provide new treatment target for control of metabolic disorder of obese patients to study adiponectin and its receptors deeply.Visfatin is a newly identified adipocytokine which is highly enriched in the visceral fat of both humans and mice. Visfatin, which not only directly binds to and stimulates the insulin receptor but also imitates insulin actions and lower plasma glucose levels, is capable of facilitating the differentiation, synthesis, accumulation of the adipose tissue. The relationship between visfatin and insulin resistance is not clear. Available researches indicate that visfatin could be the unknown link between obesity and diabetes. Moreover, the discovery of visfatin provides new content in the pathogenesis of obesity and diabetes, and it may be a useful target in drug therapies for diabetes.Part I: Effects of rVisfatin on proliferation and differentiation of human preadipocytesObjective: To investigate the effect of rVisfatin on the proliferation and differentiation of the human preadipocytes.Methods:Omental adipose tissue biopsies were obtained from patients who were undergoing elective open-abdominal surgery. The primary culture and differentiated induction of human preadipocytes were performed for total cells, and the human preadipocytes were treated with rVisfatin at different concentrations (1ng/ml,50ng/ml) at proper moments. The proliferation and differentiation of human preadipocytes were assessed with colorimetric MTT assay and oil red 0 staining.Results:Comparing with the control group, after 48 hours with rVisfatin, 1ng/ml group increased the MTT value of the human preadipocytes by 14.3% (P < 0.05), while 50ng/ml group by 17.5% (P < 0.05). The human adipocytes with rVisfatin cumulated more adipose in the endochylema than those without rVisfatin group.Conclusion:rVisfatin may promote the proliferation and differentiation of the human omental preadipocytes. Key Words: Part II: Effects of rVisfatin on expression of adiponectin mRNA in human adipocytesObjective:To investigate the effect of rVisfatin on the expression of adiponectin mRNA in human adipocytes.Methods:Omental adipose tissue biopsies were obtained from patients who were undergoing elective open-abdominal surgery. The primary culture and differentiated induction of human preadipocytes were performed for total cells, and the human preadipocytes were treated with rVisfatin at different concentrations (1ng/ml,50ng/ml) at proper moments. The expression of adiponectin mRNA in human adipocytes were assessed with RT-PCR.Results:The expression of adiponectin mRNA in human adipocytes was up-regulated after 10d of exposure to rVisfatin.Conclusion:rVisfatin may promote the expression of adiponectin mRNA of the human adipocytes.