The relationship between Lipocalin-2 level and hepatic steatosis in obese patients with NAFLD after bariatric surgery

Background Lipocalin-2 (LCN2) has a critical effect on obesity as well as its associated comorbidities. The present study focused on analyzing serum LCN2 levels of obese patients with nonalcoholic fatty liver disease (NAFLD) and on determining relationship of hepatic steatosis improvement with LCN2 levels after laparoscopic sleeve gastrectomy (LSG). Methods This work enrolled ninety patients with obesity and NAFLD. Twenty-three of them underwent LSG. Anthropometric and biochemical parameters and serum LCN2 levels were determined at baseline and those at 6-month post-LSG. Controlled attenuation parameter (CAP) measured by FibroScan was adopted for evaluating hepatic steatosis. Results Among severe obesity patients, serum LCN2 levels were significantly increased (111.59 +/- 51.16 ng/mL vs. 92.68 +/- 32.68 ng/mL, P = 0.035). The CAP value was higher indicating higher liver fat content (360.51 +/- 45.14 dB/m vs. 340.78 +/- 45.02 dB/m, P = 0.044). With regard to surgical patients, liver function, glucose, and lipid levels were significantly improved after surgery. Serum LCN2 levels significantly decreased (119.74 +/- 36.15 ng/mL vs. 87.38 +/- 51.65 ng/mL, P = 0.001). Decreased CAP indicated a significant decrease in liver fat content (358.48 +/- 46.13 dB/m vs. 260.83 +/- 69.64 dB/m, P < 0.001). The decrease in LCN2 levels was significantly related to the reduced hepatic fat content and improvement in steatosis grade after adjusting for gender, age, and BMI decrease. Conclusions Serum LCN2 levels are related to obesity and NAFLD. The decreased serum LCN2 levels could be an indicator of hepatic steatosis improvement.