PDK4 and type 1 diabetes mellitus: Furthermore, type 1 diabetic mice and WRL68 human hepatocytes subjected to high-glucose treatments were used as research models to verify that CcpA-knockout S. aureus infection activated the signal transducer and activator of the transcription 5 (STAT5)/PDK4 pathway of the liver by secreting proteins, resulting in abnormal metabolic phenotypes of diabetes.