Abstract: Objective To investigate the effect of selective β3-adrenergic receptor（β3-AR） agonist on hepatic oxidative stress and liver fibrosis in rats with nonalcoholic fatty liver disease（NAFLD）. Methods 30 male SD rats were randomly divided into control （NC）,model and and β3-AR agonist （BRL 37344） intervention group （BRL） with ten in each. Serum hyaluronic acid （HA）and transforming growth factor-β1 （TGF-β1） were detected by ELISA. The superoxide dismutase （SOD）,malondialdehyde （MDA） and glutathione peroxidase （GSH-Px） levels in liver tissue homogenates were detected by spectrophotometry. The liver tissues of rats were collected to examine the pathological changes and the degree of fibrosis. Results Serum TC,TG,ALT,AST,HA and TGF-β1 levels in BRL group were（1.95±0.43） mmol/L,（0.82±0.31） mmol/L,（71.02±11.34） U/L,（165.18±39.11） U/L, （159.64±32.50） ng/ml and（0.92±0.54） μg/ml,much higher than【（1.77±0.34） mmol/L,（0.59±0.23） mmol/L,（54.48±8.64）U/L,（134.12±37.16） U/L,（95.57±19.47） ng/ml and（0.75±0.51） μg/ml,respectively,P<0.05】 in model group,and they were all higher than 【（1.19±0.25） mmol/L,（0.35±0.19） mmol/L,（32.26±7.13）U/L,（119.64±35.16）U/L,（76.26±13.34）ng/ml and（0.69±0.46） μg/ml,respectively,P<0.05] in the NC group; hepatic SOD and GSH-Px levels in BRL were （46.31±16.39）×103U/g protein and（98.64±19.33） mg/g protein,much lower than （79.26±15.34）×103U/g protein and （126.34±21.56） mg/g protein,respectively in the model,while MDA level was（8.16±0.92）μmol/L/g protein,much higher than（5.76±0.88）μmol/L/g protein in the model （P<0.05）,and they were （113.34±12.26）×103U/g protein,（175.59±26.34）mg/g protein and（2.71±0.64） μmol/L/g protein in the control（P<0.05）;the scores of steatosis, inflammatory infiltration,ballooning degeneration and liver fibrosis in BRL were （2.71±0.34）,（2.38±0.41）,（0.86±0.21） and （4.19±0.40,much higher than【（1.94±0.34）,（1.76±0.34）,（0.61±0.16） and（3.02±0.34）,respectively,P<0.05】 in the model. Conclusion β3-AR agonist could aggravate hepatic oxidative stress and might improve liver fibrosis in rats with NAFLD,which warrants further investigation.

Key words: Nonalcoholic fatty liver disease, β3 adrenergic receptor agonist;, Oxidative stress, Liver fibrosis