Early postoperative changes of sphingomyelins and ceramides after laparoscopic sleeve gastrectomy

BACKGROUND: This study aimed to determine early postoperative changes of serum sphingomyelin (SM) and ceramide (CER) species following laparoscopic sleeve gastrectomy (LSG). METHODS: Twenty obese patients [mean body mass index (BMI) 45,64 ± 6,10 kg/m(2)] underwent LSG and normal weight control patients (mean BMI 31,51 ± 6,21 kg/m(2)) underwent laparoscopic cholecystectomy. Fasting blood samples were collected prior to surgery, at day 1 and day 30 after surgery. Circulating levels of C16-C24 SMs, C16-C24 CERs and sphingosine-1-phosphate (S1P) were determined by an optimized multiple reaction monitoring (MRM) method using ultra fast-liquid chromatography (UFLC) coupled with tandem mass spectrometry (MS/MS). Serum activity of neutral sphingomyelinase (N-SMase) was assayed by standard kit methods, and ceramide-1-phosphate (C1P) levels were determined by enzyme-linked immunosorbent assay (ELISA). Lipid profile, routine biochemical and hormone parameters were assayed by standard kit methods. Insulin sensitivity was evaluated using homeostatic model assessment for insulin resistance (HOMA IR). RESULTS: A significant decrease was observed in serum levels of very-long-chain C24 SM, very-long-chain C22-C24 CERs, HOMA-IR, N-SMase and C1P in LSG patients after postoperation day 1 and day 30 compared to preoperation levels. At 30 days postsurgery, BMI was reduced by 11%, fasting triglycerides were significantly decreased, and insulin sensitivity was increased compared to presurgery values. A significant positive correlation was found between HOMA-IR and serum levels of C22-C24 CERs in LSG patients. CONCLUSION: We conclude that very long chain CERs may mediate improved insulin sensitivity after LSG.