[Expression of peroxisome proliferator-activated receptor-gamma coactivator-1 in the liver of diabetic animals: experiment with rats].
OBJECTIVE
To investigate the expression of peroxisome proliferator-activated receptor-coactivator-1 (PGC-1) in the diabetic liver and the role thereof in the development of hyperglycemia and diabetes.


METHODS
Sixteen Wistar rats were randomly divided into 2 groups: Group A (n=11), undergoing intraperitoneal injection of streptozocin (STZ) to establish diabetic rat models, and Group B (n=6) undergoing injection of STZ and subcutaneous injection of insulin. Another 9 rats were used as normal controls (Group C). Then blood samples were collected from the abdominal aortas to examine the fasting blood glucose (FBG), serum total cholesterol (TC), triglycerides (TG), high density lipoprotein cholesterol (HDL-C), and low density lipoprotein cholesterol (LDL-C). Their livers were taken out. RT-PCR and Western blotting were used to examine the PGC-1 mRNA and protein expression.


RESULTS
The FBS and TC levels of Group A were both significantly higher than those of Group C (P < 0.01, P < 0.05). The PGC-1 protein expression level in liver of Group A was 2.47 times that of the Group C (P < 0.01) and 1.57 times that of Group B (P < 0.05). The PGC-1 mRNA expression level in the liver of Group A was (165.6 +/- 41.6), significantly higher than that of Group B [(121.6 +/- 25.4), P < 0.05] and that of Group C [(109.15 +/- 21.8), P < 0.01].


CONCLUSIONS
The PBC-1 protein and mRNA expression levels in the liver of diabetic animals are significantly higher than those of the normal livers, and can be reversed by insulin therapy. High PGC-1 expression in the diabetic liver may be related to the hyperglycemia in type 2 diabetes.
Liu
Cong
C
First Affiliated Hospital of China Medical University, Shenyang 110001, China. liucongjp@yahoo.com
Wu
Bo
B
Chen
Wei
W
Li
Li
L
Li
Ling
L
Han
Ping
P
Zheng
Chang-qing
CQ
Liu
Guo-liang
GL
D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D015153:Blotting, Western; D002784:Cholesterol / Q000097:blood; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D003921:Diabetes Mellitus, Experimental / Q000097:blood / Q000188:drug therapy / Q000378:metabolism*; D015870:Gene Expression; D007004:Hypoglycemic Agents / Q000494:pharmacology / Q000627:therapeutic use; D007328:Insulin / Q000494:pharmacology / Q000627:therapeutic use; D007333:Insulin Resistance; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014157:Transcription Factors / Q000096:biosynthesis* / Q000235:genetics; D014280:Triglycerides / Q000097:blood
D001786:Blood Glucose; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D007004:Hypoglycemic Agents; D007328:Insulin; D012333:RNA, Messenger; D014157:Transcription Factors; D014280:Triglycerides; C111264:peroxisome-proliferator-activated receptor-gamma coactivator-1; D002784:Cholesterol