Effect of ginsam, a vinegar extract from Panax ginseng, on body weight and glucose homeostasis in an obese insulin-resistant rat model.
Extracts of ginseng species show antihyperglycemic activity. We evaluated the antihyperglycemic and antiobesity effects of ginsam, a component of Panax ginseng produced by vinegar extraction, which is enriched in the ginsenoside Rg3. Otsuka Long-Evans Tokushima Fatty rats, an obese insulin-resistant rat model, were assigned into 1 of 3 groups (n = 8 each): controls (isotonic sodium chloride solution, 5 mL/d), rats given 300 mg/(kg d) ginsam, and rats given 500 mg/(kg d) ginsam. An intraperitoneal 2-hour glucose tolerance test was performed at the end of the 6-week treatment. After 8 weeks, body and liver weights, visceral fat measured by computed tomography, and fasting glucose and insulin concentrations and lipid profiles were recorded. Insulin-resistant rats treated with ginsam had lower fasting and postprandial glucose concentrations compared with vehicle-treated rats. Importantly, overall glucose excursion during the intraperitoneal 2-hour glucose tolerance test decreased by 21.5% (P < .01) in the treated rats, indicating improved glucose tolerance. Plasma insulin concentration was significantly lower in ginsam-treated rats. These changes may be related to increased glucose transporter 4 expression in skeletal muscle. Interestingly, when the data from both ginsam-treated groups were combined, body weight was 60% lower in the ginsam-treated rats than in the controls (P < .01). Liver weight and serum alanine aminotransferase concentrations were also lower in the ginsam-treated rats. These effects were associated with increased peroxisome proliferator-activated receptor gamma expression and adenosine monophosphate-activated protein kinase phosphorylation in liver and muscle. Our data suggest that ginsam has distinct beneficial effects on glucose metabolism and body weight control in an obese animal model of insulin resistance by changing the expression of genes involved in glucose and fatty acid metabolism.
Lim
Soo
S
Department of Internal Medicine, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam 463-707, South Korea.
Yoon
Ji Won
JW
Choi
Sung Hee
SH
Cho
Bong Jun
BJ
Kim
Jun Tae
JT
Chang
Ha Soon
HS
Park
Ho Seon
HS
Park
Kyong Soo
KS
Lee
Hong Kyu
HK
Kim
Young-Bum
YB
Jang
Hak Chul
HC
D000091162:AMP-Activated Protein Kinase Kinases; D050153:Abdominal Fat / Q000033:anatomy & histology / Q000187:drug effects; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects*; D002784:Cholesterol / Q000097:blood; D005947:Glucose / Q000378:metabolism*; D005951:Glucose Tolerance Test; D051275:Glucose Transporter Type 4 / Q000378:metabolism; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance / Q000502:physiology; D008099:Liver / Q000033:anatomy & histology / Q000187:drug effects / Q000378:metabolism; D008297:Male; D018482:Muscle, Skeletal / Q000187:drug effects; D009765:Obesity / Q000097:blood / Q000188:drug therapy* / Q000378:metabolism*; D009929:Organ Size / Q000187:drug effects; D047495:PPAR gamma / Q000378:metabolism; D010766:Phosphorylation; D011134:Polysaccharides / Q000494:pharmacology*; D011494:Protein Kinases / Q000378:metabolism; D051381:Rats; D020334:Rats, Inbred OLETF; D014280:Triglycerides / Q000097:blood
D001786:Blood Glucose; D051275:Glucose Transporter Type 4; D007328:Insulin; D047495:PPAR gamma; D011134:Polysaccharides; D014280:Triglycerides; C111520:ginsan; D002784:Cholesterol; D011494:Protein Kinases; D000091162:AMP-Activated Protein Kinase Kinases; D005947:Glucose