EFFECT OF THIAZOLIDINEDIONES ON ADIPOCYTOKINES AND LIPID PROFILE IN INSULIN RESISTANT SPRAGUE DAWLEY RATS
Background: Insulin resistance is manifested by decreased effect of fixed quantity of insulin on glucose metabolism leading to type 2 diabetes mellitus. Visceral obesity has been positively correlated with insulin resistance but its mechanism is not fully defined. Insulin resistance may be the consequence of adipocytokines including visfatin and resistin. This study was designed to observe the effects of thiazolidinediones on lipid profile and levels of adipocytokines (visfatin and resistin) in insulin resistant Sprague Dawley rats. Methods: Ninety Sprague Dawley rats were randomly divided into three groups. Group I served as control. Rats in Group II and III were made insulin resistant diabetics. Group III was treated with rosiglitazone after development of diabetes. Plasma glucose, serum triglycerides (TG), HDL, TG: HDL ratio and serum adipocytokines (visfatin, resistin) levels were analyzed. Results: Body weight and plasma glucose were significantly increased (p<0.05) along with TG: HDL ratio (p<0.05) in group II and group III at the end of 4th week. Serum visfatin and resistin levels also increased significantly (p<0.05) in group II and III at the end of 4th week. Treatment of group III with rosiglitazone led to improvement in insulin resistance with decrease in serum resistin levels (p<0.05) and increase in serum visfatin levels (p<0.05). Rosiglitazone treatment decreased serum TG level and increased serum HDL level. Conclusions: Deranged lipid profile and increased serum resistin levels indicate insulin resistance and impending hyperglycaemia. Thiazolidinediones augment sensitivity of insulin to restore normoglycemia by improving lipid profile, decreasing serum resistin levels and improving serum visfatin levels.
Pak J Physiol 2017;13(4):3â€“6
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