Gut Microbiota and Bile Acids in Type 2 Diabetes Mellitus

Inclusion Criteria: 1. Treatment-naïve male patients with type 2 diabetes; 2. Aged 20-65 years; 3. Body mass index (BMI) ≥ 24 kg/m2; 4.7 % ≤ glycated hemoglobin (HbA1c) \< 9 %; 5.Low-density cholesterol (LDL-C) ≥ 130 mg/dl; 6.Expected to receive metformin 500 mg tid or YH1 6g tid for one month Exclusion Criteria: 1. type 1,or other specific types of diabetes; 2. female; 3. history of oral hypoglycemic agents (OHAs) treatment or insulin therapy; 4. use of lipid-lowering drugs within the past six months; 5. serious gastrointestinal (GI) tract diseases, including peptic ulcers and GI tract bleeding; 6. hepatic insufficiency with ALT \>72 U/L or renal insufficiency with an eGFR \< 60 mL/min/1.73 m2; 7. history of stressful situations, including diabetic ketoacidosis, nonketotic hyperosmolar diabetic coma, infectious disease, or surgery in the previous month; 8. mental illness; 9. current smoking status, alcohol or drug abuse; 10. hemoglobin disease or chronic anemia; 11. underlying conditions that could lead to poor compliance; 12. severe organic diseases, including cancer, coronary heart disease, myocardial infarction or cerebrovascular disease; 13. continuous antibiotic or probiotics use for over 3 days within 3 months prior to enrollment; 14. continuous use of weight loss drug for over 1 month; 15. history of YH1 therapy, or Chinese medicine treatment within the past one month.