Hepatocyte Specific Shp1 Deletion And Low Dose Rosiglitazone Treatment Act In Concert To Improve Liver Glucose Homeostasis In Diet-Induced Obese Mice

The protein‐tyrosine phosphatase Shp1 plays a key role in high‐fat diet (HFD)‐induced insulin resistance by negatively regulating insulin action on glucose homeostasis. Hepatocyte‐specific Shp1 knockout mice (Ptpn6H‐KO) on HFD show an improvement of hepatic insulin resistance and glucose homeostasis but also develop increased hepatic steatosis compared to their wild‐type littermates (Ptpn6fl/fl). Nevertheless, livers of Ptpn6H‐KO mice on HFD have reduced hepatocellular damage and a reduced inflammatory profile alongside with increased peroxisome proliferator‐activated receptor gamma (PPARγ) activity, suggesting a new role for Shp1 in the regulation of PPARγ and the control of hepatic lipid metabolism. Therefore, the aim of the present study was to determine whether activation of PPARγ activity using rosiglitazone could further ameliorate hepatic glucose and lipid homeostasis as well as the inflammatory profile in Ptpn6H‐KO mice. Male Ptpn6H‐KO and Ptpn6fl/fl mice were fed a HFD for 18 weeks. During the last 4 weeks the animals were treated with a very low dose of rosiglitazone (0.3 mg/kg/day). Low‐dose rosiglitazone treatment did not affect total body or adipose tissue weight, plasma levels of adiponectin or expression of PPARγ target genes in adipose tissue whereas PPARγ target genes expression was highly increased in liver. However, liver weight and liver triglycerides were increased in both rosiglitazone treated groups while plasma triglycerides were reduced by rosiglitazone. Furthermore, treatment with rosiglitazone led to an improvement in whole‐body glucose homeostasis and hepatic Akt activation both of which were even more ameliorated in HFD‐fed Ptpn6H‐KO compared to Ptpn6fl/fl mice. These results show that a low‐dose rosiglitazone treatment selectively target liver metabolism without detectable effects on adipose tissue, and our data further suggest that hepatic invalidation of Shp1 acts in concert with rosiglitazone to improve glucose metabolism in liver of HFD‐fed obese mice.Support or Funding InformationCIHRThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.