| Theme |
Nonalcoholic Steatohepatitis (NASH) |
| Title |
Insulin Resistance in NASH |
| Author |
Toshiji Saibara |
First Department of Medicine, Kochi Medical School |
| Author |
Yasuko Nozaki |
First Department of Medicine, Kochi Medical School |
| Author |
Masaya Takahashi |
First Department of Medicine, Kochi Medical School |
| Author |
Masafumi Ono |
First Department of Medicine, Kochi Medical School |
| Author |
Shinji Iwasaki |
First Department of Medicine, Kochi Medical School |
| Author |
Saburo Onishi |
First Department of Medicine, Kochi Medical School |
| [ Summary ] |
In the past two decades, the number of obese persons has doubled in Japan. The number of nonalcoholic steatohepatitis (NASH) cases has been considered to be low, but the increase in the obese population has resulted in an obvious increase in life style-related diseases in the past two decades. As NASH is often associated with diseases such as obesity, diabetes mellitus and hypertriglyceridemia, the majority of NASH patients meet the diagnostic criteria for insulin resistance syndrome. Body mass index (BMI) and HOMA-IR, determined by Homeostasis model assessment for these individuals are apparently higher than those observed in healthy volunteers. 75g OGTT revealed that the majority of NASH patients suffer from diabetes mellitus or impaired glucose tolerance (IGT). Hyperinsulinemia in 75g OGTT is another characteristic feature observed in NASH patients, but the division between these is blurred and impaired insulin secretion becomes evident when liver fibrosis develops. Insulin hypersecretion may be attributable to increased insulin secretion rather than decreased hepatic extraction of insulin. Since half of NASH patients develop liver fibrosis within ten years and hepatic steatosis is a frequent, complication in patients with non-viral hepatocarcinogenesis, we must investigate the pathogenesis of NASH precisely and develop new medicines to overcome insulin resistance in the near future. |