Objective:To explore the role of obesity in sepsis-induced liver injury and inflammation.Methods:The experimental groups consisted of 80 male C57 BL/6 mice at 6 weeks of age.Animals were randomized to HFD（n=40）or ND（n=40）for 6 weeks

then they were weighed.Glucose tolerance tests were measured.The liver triglyceride levels were determined by colorimetric assay kit.Poly microbial sepsis was induced by cecal ligation-peferation（CLP） and mice were monitored for survival.Plasma and liver tissues were collected.HE staining was used to observe the liver tissue of mice.The levels of alanine aminotransferase（ALT）

leptin

adiponectin

TNF-α

IL-6 and IL-10 were detected by enzyme-linked immunosorbent assay（ELISA）.RT-PCR was used to detect the expression of activator protein-1 expression.Results:The body weight of HFD group was significantly higher than that of ND group[（34.867±1.465）vs.（25.678±1.761）

t=-9.827

P=0.000].Glucose tolerance test:compared with the ND group

the HFD group had higher blood glucose levels and higher hepatic triglyceride levels（F=200.921

P=0.000;t=31.793

P=0.000）.Obese mice had a lower survival rate and a shorter survival time（P=0.037）than ND mice in sepsis.After CLP treatment

the levels of plasma leptin in obese mice were still significantly higher than those in non-obese mice [（27.64 ±5.16） ng/mL vs.（7.12 ±2.91） ng/mL

F =95.141

P=0.000]

while adiponectin expressions were decreased in obese mice[6 h ND group vs.HFD group:（8 445.344±3 245.632）vs.（2 434.532±2.012）

t=2.660

P=0.000].The expressions of TNF-α

IL-6 and IL-10 were increased in septic mice[TNF-α:（2.017±1.071）vs.（170.698±37.705）

t=8.137

P=0.001;（2.760±0.853）vs.（122.080±19.520）

t=13.553

P=0.000;IL-6:（19.955±3.500）vs.（404.752±50.701）

t=18.070

P=0.000;（15.975±4.022）vs.（533.064±104.866）

t=11.032

P=0.000;IL-10:（79.810±7.042）vs.（277.156±124.213）

t=4.335

P=0.012;（120.678±7.172）vs.（214.111±85.322）

t=3.925

P=0.020]

but the expression of TNF-α and IL-10 in obese mice was lower than that in non-obese mice[TNF-α:（170.698±37.705）vs.（122.080±19.520）

t=0.981

P=0.356;IL-10:（277.156±124.213）vs.（214.111±85.322）

t=3.216

P=0.031].Plasma ALT levels were significantly higher in obese sepsis mice than in non-obese sepsis mice[（132.774 ±45.662）vs.（236.633±42.782）

t=2.831

P=0.045].Although AP-1 activity increased in mice without obesity at 6 h after CLP

AP-1 activity was significantly higher in mice with obesity than in mice without obesity after CLP[ND 0 h vs.6 h:（1.069±0.404）vs.（1.653±0.184）

F=32.886

P=0.000;6 h ND vs.HFD:（1.653±0.184）vs.（5.021 ±0.623）

F=29.189

P=0.000].Conclusion:High fat diet induced obese mice in sepsis have low survival rate

severe liver injury

decreased inflammatory response

which may be related to increased activity of AP-1.