Correlation between serum ceramide subspecies and metabolic disorders in obese patients in the early stage of post-laparoscopic sleeve gastrectomy

Objective To evaluate the changes in serum ceramide (CER) and its subspecies in obese patients at 1 month after laparoscopic sleeve gastrectomy (LSG) and explore the correlation between serum ceramide subtypes and metabolic disorders. Methods A total of 34 obese patients undergoing LSG [obese group, mean age was (29.0±8.9) years, 30 female (88.2%),4 male (11.8%)] and 31 healthy subjects [normal group,mean age was (24.8±3.8) years, 18 female (58.1%) , 13 male (41.9%) ] who had not received anti-obesity treatment were recruited in the First Affiliated Hospital of Nanjing Medical University from November 2017 to May 2018. The clinical data of obese patients were collected and compared before surgery and 1 month after LSG. Insulin resistance was evaluated with homeostasis model assessment of insulin resistance (HOMA-IR). Serum lipidomics analysis was performed in an electrospray ionization mode using Exion UPLC-QTRAP 6500 PLUS (Sciex) LC/MS. The t test, Wilcoxon rank test and SNK-q test were wsed for statistical analysis. Pearson and Spearman rank correlation analysis were used to analyze the correlation between CER and serological indexes. Results 1 month after LSG, serum ceramides including Cer d18∶1/22∶0 [piror and post LSG respectively: 0.99(0.83,1.25), 0.55(0.45,0.77) pmol/L, Z=4.59, P<0.01] and Cer d18∶1/24∶0 [piror and post LSG respectively: 2.63(2.22,3.45), 1.46(0.99,2.22) pmol/L, Z=5.10, P<0.01] decreased in 34 obese patients, and they were significantly positively correlated with body mass index, total cholesterol, low density lipoprotein cholesterol, HOMA-IR, C-reactive protein, and interleukin-6 (r=0.26-0.59, all P<0.05). Conclusion Cer d18∶1/22∶0 and Cer d18∶1/24∶0 may be related to the recovery of insulin resistance, reduction of inflammatory cytokines and cardiovascular risk in obese patients treated with LSG. Key words: Obesity; Ceramides; Laparoscopic sleeve gastrectomy; Insulin resistance