Possible role of ginsenoside Rb1 on regulation of rat liver triglycerides.
We have studied the effects of ginsenoside Rb1 (GRb1) on the change in lipid contents in rat liver. When GRb1 was administered intraperitoneally to rats, liver microsomal cytochrome P-450 content and NADPH-cytochrome P-450 reductase activity were lower than those in control rats. The contents of triglyceride (TG) and cholesterol were decreased, but those of total phospholipid, phosphatidylcholine, and phosphatidylethanolamine were increased in the GRb1-treated group compared with controls. These results indicate that GRb1 might be involved in lipid metabolism by regulating the activity of microsomal cytochrome P-450 monooxygenase. Although liver TG levels were reduced by GRb1, the levels of TG and beta-lipoprotein in serum from the GRb1-treated group did not change as compared with those in controls. Thus we suggest that the decrease in liver TG levels with GRb1-treatment is not associated with the secretion of TG-rich very low-density lipoprotein. Furthermore, the level of cAMP was also significantly increased in the GRb1-treated group as compared with that in controls. Additionally, the cAMP level was more markedly increased as compared with that in the GRb1-treated group or control group when GRb, was exogenously added to the reaction system for measuring cAMP production in homogenates from control group liver. Accordingly, these results demonstrate that GRb1 might lower TG levels via cAMP-production in the liver, and GRb1 might be an interesting candidate to for a modulator of cAMP-mediated effects, especially within the liver steatosis system.
Park
Ki-Hyun
KH
Department of Biomedical Pharmacology, Korea Ginseng and Tobacco Research Institute, Taejon.
Shin
Han-Jae
HJ
Song
Young-Bum
YB
Hyun
Hak-Chul
HC
Cho
Hyun-Jeong
HJ
Ham
Hye-Seon
HS
Yoo
Young-Bin
YB
Ko
Young-Chul
YC
Jun
Woong-Tak
WT
Park
Hwa-Jin
HJ
D000818:Animals; D000242:Cyclic AMP / Q000378:metabolism; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D036145:Ginsenosides / Q000008:administration & dosage / Q000494:pharmacology*; D007274:Injections, Intraperitoneal; D008099:Liver / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D008862:Microsomes, Liver / Q000187:drug effects / Q000378:metabolism; D005894:Panax / Q000737:chemistry; D051381:Rats; D017207:Rats, Sprague-Dawley; D014280:Triglycerides / Q000378:metabolism*
D036145:Ginsenosides; D014280:Triglycerides; C442759:ginsenoside Rb1; D003577:Cytochrome P-450 Enzyme System; D000242:Cyclic AMP