Objective:To investigate the effect of Ophiopogonis Radix extract on expressions of miRNA-29a and FOXO3 in liver tissues of insulin resistant rats. Method:A total of 60 male SD rats were selected

including 10 for normal control. The remaining 50 rats were randomly divided into model control group

high

medium and low-dose Ophiopogonis Radix extract groups

metformin positive control group 5

with 10 in each group. High

medium and low-dose Ophiopogonis Radix extract groups were given 150

300

500 mg·kg-1 Ophiopogonis Radix extract

the positive control group was given 200 mg·kg-1 metformin suspension through intragastric administration for intervention

while the normal control group and the model control group were given the same volume of saline. The levels of body weight (BW)

liver weight (LW)

fasting blood glucose (FBG)

total cholesterol (TC)

triglyceride (TG)

fasting insulin (FINs)

insulin sensitivity index (ISI)

liver index (LI) and C-peptide were measured by hematoxylin-eosin(HE) staining. The pathological changes in liver were observed

and the expressions of miRNA-29a and FOXO3 in liver tissues were detected by Real-time PCR at the 4th and 8th weeks after administration. Result:The rats in the normal control group were given normal diets

with clean skin and in a good mental state. The rats in the model control group were lethargic and lazy

with messy and dim skin. The Ophiopogonis Radix extract and the metformin groups had dim skin

with a better mental state than the model control group. Ophiopogonis Radix extract significantly reduced the levels of BW

LW

C-peptide and LI in insulin resistance rats (P<0.05)

significantly reduced the levels of TC

TG and FINs (P<0.05)

significantly increased ISI levels (P<0.05)

and improved insulin resistance in rats. Ophiopogonis Radix extract significantly relieved steatosis of rats in the insulin resistance model and pathological status of liver. Ophiopogonis Radix extract significantly down-regulated miRNA-29a expression

and up-regulated FOXO3 expression

in a dose-dependent manner (P<0.05). Conclusion:Ophiopogonis Radix extract can significantly relieve insulin resistance

suggesting that its mechanism is down-regulation of miRNA-29a expression and up-regulation of FOXO3 expression.