Expression of resistin mRNA in adipose tissue of rat model with polycystic ovarian syndrome and its implication

Abstract

To investigate the relationship between the insulin resistance (IR) of polycystic ovarian syndrome (PCOS) rat model induced by dehydroeplandrosterone (DHEA) and hormonal changes in the ovarium and the resistin mRNA levels in adipose tissue, 21-day-old female SD rats were divided into two groups in pairs. The rats in group 1 were injected daily (s. c) with DHEA for up to 20 days and the rats in group 2 injected with oil at the same time. Ovarian weight, serum insulin levels and sex hormone levels in rat blood of both groups were determineds. Oral glucose tolerance tests, light microscopic and electronic microscopic examination were performed. The levels of resistin mRNA in adipose tissue were measured by reverse transcription-polymerase chain reaction (RT-PCR). Our results showed that the ovarian weight in group 1 was greater than that in group 2 (P<0.05). The ovaria in group 1 showed multiple follicular cysts. The serum testeosterone and etrasdiol concentration were significantly higher in group 1 than those in group 2 (P<0.001 andP<0.05 respectively), so as the fasting serum glucose (P<0.001) and fasting serum insulin (P<0.05). The value of 1/FINS×FGC was significantly higher in group 1 than that in group 2 (P<0.001). Moreover, the resistin mRNA level of white adipose tissue in the DHEA-induced group was significantly higher than that in the control rats (P<0.05). It is concluded that the DHEA-induced PCOS rat models were similar to those of the patients with PCOS, and the IR was observed. Resistin secreted by adipose tissue may mediate IR in PCOS, and it is likely involved in the pathogenesis and development of PCOS.

Keywords

polycystic ovarian syndrome / resistin / animal model

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