[Preventive effect of radix Astragali on insulin resistance caused by tumor necrosis factor-alpha].
OBJECTIVE
To investigate the preventive effect of Radix Astragali (RA) on insulin resistance caused by tumor necrosis factor-alpha (TNF-alpha).


METHODS
Normal rats were pretreated with RA or distilled water by intragastric infusion for one week. Glucose-insulin tolerance test was conducted in the rats 4 h after low dose TNF-alpha injection by caudal vein to estimate the change in insulin sensitivity. Meanwhile, the plasma glucagon, ACTH, blood lipid, and glycogen, triglyceride in tissue were also observed.


RESULTS
Exogenous TNF-alpha could induce hyperinsulinemia in normal rats. K value in glucose-insulin tolerance test decreased, serum ACTH, glucagon, blood lipid increased, glycogen content in liver and red quadriceps muscles decreased, the liver triglyceride level increased in the TNF-alpha treated rats. RA could improve all the above-mentioned changes significantly except the blood lipid and triglyceride depots in liver.


CONCLUSIONS
RA has obvious preventive effect on insulin resistance caused by TNF-alpha, it may be due to its action in decreasing insulin antagonistic hormones and increasing glycogen synthesis in tissue.
Lu
J
J
Department of Endocrinology, Changhai Hospital, Second Military Medical University, Shanghai (200433).
Zou
D
D
Zhang
J
J
D000818:Animals; D027883:Astragalus Plant; D027885:Astragalus propinquus; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D007333:Insulin Resistance; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors
D004365:Drugs, Chinese Herbal; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha; C027492:Huang Qi