Molecular mechanisms of diabetes reversibility after bariatric surgery

Objective: Insulin resistance is a strong biological marker of both obesity and type 2 diabetes. Abnormal fat deposition within skeletal muscle has been identified as a mechanism of obesity-associated insulin resistance. Biliopancreatic diversion (BPD), inducing a massive lipid malabsorption, leads to a reversion of type 2 diabetes. To elucidate the mechanisms of diabetes reversibility, the expression of genes involved in glucose and free fatty acids (FFAs) metabolism was investigated in skeletal muscle biopsies from obese, type 2 diabetic subjects. Peripheral insulin sensitivity and insulin secretion was also measured. Subjects: Eight Caucasian obese diabetic patients (BMI 52.1±1.85 kg/m²) were studied before and 3 years after BPD. Measurements: The mRNA levels were estimated by quantitative real-time reverse transcription polymerase chain reaction (RT-PCR), insulin sensitivity by the euglycemic-hyperinsulinemic clamp and insulin secretion using a model describing the relationship between insulin secretion and glucose concentration. Results: Whole-body glucose uptake (M), normalized by fat-free mass, significantly increased in post-obese subjects (P