Depot-specific differences in adipocyte insulin sensitivity in mice are diet- and function-dependent

Fat depots of different localization vary in their biological/metabolic function. We recently provided evidence for different regulation of lipolysis between perigonadal and mesenteric adipocytes; in particular insulin-induced suppression of lipolysis was significantly higher in perigonadal compared with mesenteric adipocytes in chow-fed mice. Moreover, insulin's anti-lipolytic effect was maintained in mesenteric but lost in perigonadal adipocytes under high fat diet (HFD). Herein, we expanded our previous study and included inguinal (subcutaneous) adipocytes in our analysis. When compared with perigonadal adipocytes, inguinal adipocytes are equally sensitive to insulin's anti-lipolytic effect under chow diet. However, they remain insulin-sensitive under HFD. Moreover, insulin-stimulated glucose incorporation was equally blunted in adipocytes of all three depots in HFD-fed mice. In conclusion, regulation of insulin sensitivity in murine adipocytes is diet-, depot- and function-dependent.