Cyclosporine A enhances gluconeogenesis while sirolimus impairs insulin signaling in peripheral tissues after 3 weeks of treatment

Abstract Cyclosporine A (CsA) and sirolimus (SRL) are immunosuppressive agents (IA) associated with new-onset diabetes after transplantation (NODAT). This study aims to evaluate the effects of 3-weeks of treatment with either CsA (5 mg/kg BW/day) or SRL (1 mg/kg BW/day) on insulin signaling and expression of markers involved in glucose metabolism in insulin-sensitive tissues, in Wistar rats. Although no differences were observed in fasting glucose, insulin or C-peptide levels, both treated groups displayed an impaired glucose excursion during both glucose and insulin tolerance tests. These results suggest glucose intolerance and insulin resistance. An increase in glucose-6-phosphatase protein levels (68%, p p p p Taken together, these data suggest that CsA treatment enhances gluconeogenic factors in liver, while SRL treatment impairs insulin signaling in peripheral tissues, which can contribute to the development of insulin resistance and NODAT associated with immunosuppressive therapy.