Antidiabetic effect of long-term supplementation with Siraitia grosvenori on the spontaneously diabetic Goto-Kakizaki rat.
Siraitia grosvenori Swingle (SG) is a traditional Chinese fruit used as a folk medicine. Its extract (SG-ex) contains potent sweet elements with a sweetness several hundred times higher than table sugar. We investigated the antidiabetic effect of SG-ex in the type 2 diabetic Goto-Kakizaki (GK) rat. Diabetic 7-week-old GK rats were fed a diet supplemented with 0.4 % of the SG-ex for 13 weeks, and its antidiabetic effects were evaluated. SG-ex had no effect on food intake or body weight. In oral glucose tolerance tests (OGTT), SG-ex supplementation improved the insulin response at 15 min (control, 63 (sem 6) pm; SG-ex, 107 (sem 20) pm; P < 0.05) and reduced the plasma glucose level at 120 min after the glucose administration (control, 18.5 (sem 0.8) mm; SG-ex, 14.8 (sem 0.7) mm; P < 0.05). The total amount of insulin in whole pancreas taken from fasting rats was higher in the SG-ex-supplemented group, which may explain the greater capacity to secrete insulin during the OGTT. Thiobarbituric acid-reactive substances in both the liver and the plasma were lower in the SG-ex-supplemented group, suggesting that an absorbable component in SG-ex has an antioxidative effect on lipid peroxidation, thereby counteracting the oxidative stress caused by a diabetic state. Excreted urine volume and urinary albumin level for 24 h were both reduced in the SG-ex-supplemented group, suggesting the attenuation of kidney damage that is caused by diabetes. These data indicate that SG-ex supplementation may prevent complications and attenuate pathological conditions for type 2 diabetes, along with its sweet characteristics.
Suzuki
Yasushi A
YA
Biochemical Laboratory, Saraya Company Ltd, Kashiwara, Osaka, 582-0028, Japan. suzuki-y@saraya.com
Tomoda
Mayuko
M
Murata
Yuji
Y
Inui
Hiroshi
H
Sugiura
Masaki
M
Nakano
Yoshihisa
Y
D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D019662:Cucurbitaceae; D048909:Diabetes Complications / Q000517:prevention & control; D003921:Diabetes Mellitus, Experimental / Q000097:blood / Q000188:drug therapy* / Q000652:urine; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000188:drug therapy* / Q000652:urine; D004435:Eating / Q000187:drug effects; D005951:Glucose Tolerance Test; D007328:Insulin / Q000032:analysis; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D010179:Pancreas / Q000737:chemistry; D008517:Phytotherapy / Q000379:methods*; D010936:Plant Extracts / Q000627:therapeutic use; D051381:Rats; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism
D001786:Blood Glucose; D007328:Insulin; D010936:Plant Extracts; D017392:Thiobarbituric Acid Reactive Substances