Obesity, insulin resistance and the implication of thiazolidinediones

The mechanism of insulin resistance in obesity is not fully understood. In muscle cells, the number of insulin receptor, the function of glucose transporter 4 and the activity of tyrosine kinase decrease. The rink of body fat accumulation and insulin resistance in muscle is thought through free fatty acid and tumor necrosis factor alpha secreted in adipose tissue. Thiazolidinediones (TZDs) are useful to reduce insulin resistance especially in obesity. TZDs seem to cause small weight gain, but to reduce visceral fat in 12-24 weeks. In longer period, it hasn't been studied very much. There are some unsolved problems. So now, targets of TZDs are obese diabetes failed in other medicines. When using TZDs, be cautious of excess eating and physical inactivity.