Supplementation of SK1 from Platycodi radix ameliorates obesity and glucose intolerance in mice fed a high-fat diet.
This study investigated the beneficial effects of SK1 on obesity and insulin resistance in C57BL/6 mice, which were fed a high-fat diet (37% calories from fat). SK1 is an edible saponin-rich compound from Platycodi radix. The mice were supplemented with two doses of SK1 (0.5% and 1.0%, wt/wt) for 9 weeks. The body weight, visceral fat mass, and adipocyte area were significantly decreased in the SK1 supplemented-groups in a dose-dependent manner compared to the high-fat group. The SK1 supplement significantly lowered plasma triglycerides, total cholesterol, and free fatty acid levels, whereas it significantly elevated the fecal excretion of lipids in the diet-induced obese mice. Supplementation of SK1 decreased the triglyceride and cholesterol levels and the accumulation of lipid droplets in the liver compared to the high-fat control group. High-fat diet induced glucose intolerance and insulin resistance with the elevation of blood glucose levels compared to the normal group; however, the SK1 supplement significantly improved postprandial glucose levels and insulin resistance index. After 9 weeks of being fed a high-fat diet, the mice presented with significantly increased activities of hepatic fatty acid synthase, fatty acid beta-oxidation, and glucokinase; however, both 0.5% and 1.0% SK1 supplementation normalized these activities. Notably, SK1 supplementation effectively diminished the ratio of fatty acid biosynthesis to fatty acid oxidation compared to the high-fat group. These results indicate that SK1 exhibits a potential anti-obesity effect and may prevent glucose intolerance by reducing body weight and fat accumulation, increasing fecal lipid excretions, and regulating hepatic lipid and glucose metabolism in high-fat fed mice.
Kim
Jae-Yong
JY
Department of Food Science and Technology, Kyungpook National University, Daegu, Republic of Korea.
Moon
Kwang-Deog
KD
Seo
Kwon-Il
KI
Park
Kyung-Wuk
KW
Choi
Myung-Sook
MS
Do
Gyeong-Min
GM
Jeong
Yong-Kee
YK
Cho
Young-Su
YS
Lee
Mi-Kyung
MK
D000273:Adipose Tissue / Q000187:drug effects; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D004041:Dietary Fats / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D002149:Energy Intake / Q000187:drug effects; D005243:Feces / Q000737:chemistry; D018149:Glucose Intolerance / Q000188:drug therapy* / Q000378:metabolism; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D050356:Lipid Metabolism; D008099:Liver / Q000201:enzymology / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009765:Obesity / Q000188:drug therapy* / Q000378:metabolism; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use*; D018517:Plant Roots; D031238:Platycodon / Q000737:chemistry*; D012503:Saponins / Q000494:pharmacology / Q000627:therapeutic use
D001786:Blood Glucose; D004041:Dietary Fats; D007328:Insulin; D010936:Plant Extracts; D012503:Saponins