Korean J Intern Med.  2018 Mar;33(2):347-355. 10.3904/kjim.2015.208.

Compound K attenuates glucose intolerance and hepatic steatosis through AMPK-dependent pathways in type 2 diabetic OLETF rats

• Hwang YC
• Oh DH
• Choi MC
• Lee SY
• Ahn KJ
• Chung HY
• Lim SJ
• Chung SH
• Jeong IK

• KMID: 2411547
• DOI: http://doi.org/10.3904/kjim.2015.208

Abstract

BACKGROUND/AIMS
Non-alcoholic fatty liver disease is associated with insulin resistance. Compound K (CK) is the final metabolite of panaxadiol ginsenosides that have been shown to exert antidiabetic effects. However, the molecular mechanism of the antidiabetic effects in the liver have not been elucidated; further, whether CK has beneficial effects in hepatosteatosis remains unclear. Therefore, we evaluated the effect of CK on hepatosteatosis as well as its mechanism in high-fat diet (HFD)-fed type 2 diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats.
METHODS
Twenty-four-week-old male OLETF rats were assigned to four groups: control (saline), CK 10 mg/kg, CK 25 mg/kg, or metformin 300 mg/kg (positive control); all treatments were administered orally for 12 weeks.
RESULTS
Fasting glucose levels of the CK25 group were significantly lower than those of the control group during the 12 weeks. The results of the oral glucose tolerance test showed that both the glucose concentration after glucose loading and the fasting insulin levels of the CK25 group were significantly lower than those of the control. Hepatosteatosis was significantly improved by CK25. CK25 and metformin significantly increased the phosphorylation of hepatic adenosine monophosphate-activated protein kinase (AMPK). CK25 significantly inhibited the expression of sterol regulatory element-binding protein-1c and fatty acid synthase, while upregulating that of peroxisome proliferator-activated receptor-α and carnitine palmitoyltransferase-1.
CONCLUSIONS
CK improved glucose intolerance and hepatosteatosis in HFD-fed OLETF rats through AMPK activation, which has dual mode of action that involves decreasing the synthesis of fatty acids and increasing fatty acid oxidation.

Keyword

Diabetes mellitus, type 2; Ginsenoside M1; Non-alcoholic fatty liver disease; AMP-activated protein kinases

MeSH Terms

Adenosine
AMP-Activated Protein Kinases
Animals
Carnitine
Diabetes Mellitus, Type 2
Diet, High-Fat
Fasting
Fatty Acids
Ginsenosides
Glucose Intolerance*
Glucose Tolerance Test
Glucose*
Humans
Insulin
Insulin Resistance
Liver
Male
Metformin
Non-alcoholic Fatty Liver Disease
Peroxisomes
Phosphorylation
Protein Kinases
Rats
Rats, Inbred OLETF*
AMP-Activated Protein Kinases
Adenosine
Carnitine
Fatty Acids
Ginsenosides
Glucose
Insulin
Metformin
Protein Kinases