[Effect of soy isoflavone on gene expression of leptin and insulin sensibility in insulin-resistant rats].
OBJECTIVE
To explore the effects of soy isoflavone (SIF) on gene expression of leptin and insulin sensibility in insulin-resistant (IR) rats induced by high-fat, and to reveal the mechanisms of SIF in ameliorating insulin sensibility.


METHODS
IR rats were randomly divided into four groups based on their insulin-resistant indexes (IRI): one model control group and three SIF groups that were gavaged with water solutions with SIF at doses of 0 mg/kg, 50 mg/kg, 150 mg/kg, and 450 mg/kg, respectively. After one month, fasting glucose, fasting insulin, leptin in serum, and leptin mRNA in the perirenal adipocyte were detected by enzymic method, radioimmunoassay, enzyme linked immunosorbent assay, and real time quantitative RT-PCR, respectively.


RESULTS
The model control group was used to compare against the other groups: (1) Insulin and IRI were lower in the 150 mg/kg and 450 mg/kg groups; (2) In the 450 mg/kg group, body weight and leptin mRNA expression were lower, serum leptin content was higher.


CONCLUSIONS
These results indicate that soy isoflavone might decrease body weight of rats and leptin mRNA, increase serum leptin level, and ameliorate leptin and insulin sensitivities.
Chen
Shi-wei
SW
Department of Nutrition and Food Hygiene, West China School of Public Health, Sichuan University, Chengdu 610041, China.
Zhang
Li-shi
LS
Zhang
Hong-min
HM
Feng
Xiao-fan
XF
Peng
Xiao-li
XL
D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D001835:Body Weight; D015870:Gene Expression; D007328:Insulin / Q000097:blood*; D007333:Insulin Resistance; D007529:Isoflavones / Q000494:pharmacology*; D020738:Leptin / Q000097:blood*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013025:Glycine max / Q000737:chemistry
D001786:Blood Glucose; D007328:Insulin; D007529:Isoflavones; D020738:Leptin