The protective mechanism of magnolol, a Chinese herb drug, against warm ischemia-reperfusion injury of rat liver.
BACKGROUND
Cell apoptosis following warm ischemia-reperfusion injury is a major concern in clinical issues such as organ transplantation, trauma, and cardiogenic shock. The purpose of this study was to evaluate the possible role of magnolol, a Chinese herb drug, in apoptotic injury and the kinetic expression of apoptotic-related genes in rat livers subjected to warm ischemia-reperfusion (WI/R).


METHODS
Three weeks prior to the experiment 10 rats underwent a portosystemic shunt operation according to Bengmerk's method. The rats were divided into three groups. Group 1 (GI) was the control group, Group 2 (GII) and Group 3 (GIII) the magnolol-treated groups. GI and GII were subjected to 2 h and GIII to 3 h of WI/R by clamping the portal vein and hepatic artery under ether anesthesia.


RESULTS
Results show that all the control rats died after 2 h WI/R. Apoptotic cells were detected under microscopy as well as by DNA assay. Magnolol-treated groups tolerated warm ischemia-reperfusion for 2 h and significantly less apoptotic cells were observed (198 +/- 22 vs 42.6 +/- 28). But magnolol-treated rats could not tolerate 3 h warm ischemia-reperfusion. RT-PCR of liver tissue shows that there is an upregulated expression of the anti-apoptotic Bcl-xL gene and suppression of the Bcl-xS gene in GII.


CONCLUSIONS
Magnolol has an anti-apoptotic effect and protects the liver against WI/R for 2 h but not for 3 h through upregulation of the anti-apoptotic Bcl-XL gene and suppression of the Bcl-xS gene.
Jawan
Bruno
B
First Department of Anesthesiology, Chang Gung Memorial Hospital, Kaohsiung Medical Center, Chang Gung University, 123 Ta-Pei Road, Niao-Sung, Kaohsiung, Taiwan. jawanb@hotmail.com
Goto
Shigeru
S
Pan
Tair-Long
TL
Lai
Chia-Yun
CY
Luk
Hsiang-Ning
HN
Eng
Hock-Liew
HL
Lin
Yu-Chun
YC
Chen
Yaw-Sen
YS
Lan
Kok-Mao
KM
Hsieh
Sao-Wei
SW
Wang
Chih Chi
CC
Cheng
Yu-Fan
YF
Chen
Chao-Long
CL
D000818:Animals; D017209:Apoptosis / Q000187:drug effects* / Q000235:genetics; D001713:Biphenyl Compounds / Q000494:pharmacology*; D004365:Drugs, Chinese Herbal / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005786:Gene Expression Regulation; D017705:Lignans; D008099:Liver / Q000098:blood supply* / Q000187:drug effects* / Q000503:physiopathology; D023421:Models, Animal; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000502:physiology; D051381:Rats; D015427:Reperfusion Injury / Q000188:drug therapy* / Q000235:genetics / Q000503:physiopathology; D051020:bcl-X Protein
C494813:Bcl2l1 protein, rat; D001713:Biphenyl Compounds; D004365:Drugs, Chinese Herbal; D004791:Enzyme Inhibitors; D017705:Lignans; D019253:Proto-Oncogene Proteins c-bcl-2; D051020:bcl-X Protein; C005498:magnolol; D019001:Nitric Oxide Synthase