Alterations in Fat Mass and Bone Mineral Density Are Associated with Decreased Lipocalin-2 After Laparoscopic Sleeve Gastrectomy in Obese Chinese Women

Objective Lipocalin-2 (LCN2) plays an important role in the regulation of the obesity and obesity-related dysmetabolic state. This study aimed to analyze serum LCN2 level in Chinese women with obesity before and after laparoscopic sleeve gastrectomy (LSG) and determine the association between alteration in fat mass and bone mineral density (BMD) and LCN2 level. Methods Fifty-two women (38 patients with obesity and 14 with normal body mass index (BMI)) were enrolled in this study. All patients with obesity underwent LSG. BMDs of the arm, leg, thoracic and lumbar spine, and pelvis were measured by dual-energy X-ray absorptiometry. Body fat mass and distribution were measured by dual-energy X-ray absorptiometry, and routine anthropometric/laboratory biochemical parameters at baseline and 3 and 12 months after LSG were recorded. Serum LCN2 levels were measured using an enzyme-linked immunosorbent assay. Results Serum LCN2 level was significantly higher in women with obesity than in the controls with normal BMI (102.70 ± 27.19 vs. 80.66 ± 19.55 ng/mL, P = 0.009). LCN2 level was decreased at 3 and 12 months after LSG (86.73 ± 26.79 ng/mL, P = 0.171, and 64.79 ± 28.39 ng/mL, P < 0.001, respectively). LSG led to marked body fat mass and slight BMD decrease. Decreased LCN2 level was significantly correlated with alterations in left and right leg BMDs and trunk fat mass at 12 months after LSG. Conclusions Obesity was associated with up-regulated serum LCN2 level. Decreased LCN2 level was positively correlated with changes in BMD and fat mass at 12 months after LSG in Chinese women.