DDIT4 and Insulin resistance: The findings that mangiferin ameliorates insulin resistance by activating the PPARα pathway (61), resveratrol enhances PA-induced insulin resistance via the DDIT4/mTOR pathway (62), and downregulation of lipin-1 induces insulin resistance by elevating intracellular ceramide accumulation (63), were all derived from the experiments using insulin resistance C2C12 cell models.