Biochemia Medica, Vol. 16 No. 1, 2006.
Review article
Molecular Mechanisms of Insulin Resistance, Obesity and Metabolic Syndrome
Barbara Mlinar
Janja Marc
Marija Pfeifer
Abstract
Insulin resistance is a state of impaired responsiveness to insulin action. The most common underlying cause is central obesity although primary insulin resistance in normal-weight individuals is also possible. Excess abdominal adipose tissue has been shown to release increased amounts of tumor necrosis factor α and free fatty acids, which directly affect insulin signaling, diminish glucose uptake in the muscle, drive exaggerated triglyceride synthesis and induce gluconeogenesis in the liver. Other factors presumed to play a role in insulin resistance are adiponectin (a decrease), leptin, IL-6 and some other adipokines. Common obesity is thought to be of polygenic origin with influence of "obesogenic" environment, i.e. increased food intake and the lack of physical activity. Today's high prevalence of obesity could be explained by evolutionary pressure for selection of genes promoting fat storage to survive in starvation. Insulin resistance frequently coexists with central obesity, hypertension and dyslipidemia, which have collectively been denoted as metabolic syndrome. These manifestations represent strong risk factors for diabetes mellitus type 2 and cardiovascular disease.
Keywords
insulin resistance; obesity; metabolic syndrome; adipokines
Hrčak ID:
11531
URI
Publication date:
15.5.2006.
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