Insulin-like effects of vanadate on rat liver 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase mRNA and protein inductions in diabetic rats.
Effects of vanadate on liver 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (6PF-2-K/F-2,6-P2ase) mRNA and protein inductions were examined in streptozotocin (STZ)-induced diabetic rats. In diabetic rats at one week after STZ (60 mg/kg body weight), the liver 6PF-2-K activity was decreased to 22% of the control. The enzyme protein was also decreased to 31% of the control, but the reduction in mRNA was not significant. Treatment of diabetes with vanadate (10 mg/kg BW, i.v., every 8 h), as well as insulin (10 u/kg BW, s.c., every 8 h), increased the 6PF-2-K activity and the enzyme protein content, though it was not completely restored to the control level. 68% of the control was the figure for enzyme activity and 65% of the control for protein content after 24-h of treatment. On the other hand, vanadate, like insulin, increased enzyme mRNA content to a higher level than the control (140% of the control). The present results indicate that vanadate, like insulin, modulates the liver 6PF-2-K/Fru-2,6-P2ase gene expression, and stimulated protein induction contributes to the regulation of its enzyme activity, resulting in amelioration of the deranged carbohydrate metabolism in the diabetic state.
3rd Department of Medicine, Yamaguchi University School of Medicine, Ube, Japan.
H
H
Inoue
K
K
Kaku
A
A
Matsutani
T
T
Tao
H
H
Ayame
T
T
Kaneko
D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy / Q000201:enzymology* / Q000378:metabolism; D007328:Insulin / Q000097:blood / Q000494:pharmacology*; D008099:Liver / Q000187:drug effects* / Q000201:enzymology; D025481:Phosphofructokinase-2; D010744:Phosphoric Monoester Hydrolases / Q000235:genetics*; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000235:genetics*; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000187:drug effects*; D051381:Rats; D014638:Vanadates / Q000494:pharmacology*
D001786:Blood Glucose; D007328:Insulin; D012333:RNA, Messenger; D014638:Vanadates; D017853:Phosphotransferases (Alcohol Group Acceptor); D025481:Phosphofructokinase-2; D010744:Phosphoric Monoester Hydrolases