Effect of aging on the development of glucose intolerance induced by a low-carbohydrate diet in rats

The effect of aging on the development of glucose intolerance between 2 kinds of diets, a low-carbohydrate/high-fat (LC/HF) diet and a control diet was investigated. A total of 20 eight-week-old S.D. rats were randomly divided into 2 groups of 10 rats each and at 10, 20, 40, 60 and 80 weeks of age, rats were switched to either control or LC/HF diet for 7 days. At 16:00 on the day following the 7th day of feeding, rats underwent an oral glucose tolerance test (OGTT). LC/HF feeding for 7 days impaired the glucose tolerance in rats. Moreover, insulin secretion decreased with age and insulin resistance increased after 60 weeks of age when rats were fed the LC/HF diet, and fasting plasma free fatty acids (FFA) concentrations increased with age. Thus, we speculated that the age-related impairment of insulin action through the glucose fatty-acid cycle might be closely associated with the onset and development of diabetes mellitus.