Serum Fibrinogen-Like Protein 1 Levels in Obese Patients Before and After Laparoscopic Sleeve Gastrectomy: A Six-Month Longitudinal Study

Purpose: Fibrinogen-like protein (FGL)-1 is an original hepatokine with a critical role in developing hepatic steatosis. This study intends to examine the pre-and postoperative serum FGL-1 levels in bariatric patients and identify its relationship with other clinical indicators. Patients and Methods: Ninety-two individuals (60 bariatric patients and 32 people with normal weight) were enrolled in this research between July 2018 and April 2021. All bariatric patients finished follow-up visits 6 months after laparoscopic sleeve gastrectomy (LSG). Clinical data, anthropometric parameters, biochemical variables, FibroScan, and serum FGL-1 levels were collected at baseline and 6 months after LSG.Results: FGL-1 levels in patients with obesity (44.66 +/- 20.03 ng/mL) were higher than in individuals with normal weight (20.73 +/- 9.73 ng/mL, p < 0.001). After LSG, FGL-1 levels were significantly decreased (27.53 +/- 11.45 ng/mL, p < 0.001). Besides, body mass index (BMI), liver enzyme levels, glucose metabolism, lipid metabolism, uric acid (UA), controlled attenuation parameter (CAP), and liver stiffness measurement (LSM) were significantly improved. After adjusting possible confounders, FGL-1 levels at baseline were negatively associated with changes in LSM levels; changes in FGL-1 levels showed positive correlations with changes in alanine aminotransferase (ALT), aspartate aminotransferase (AST) and UA levels at 6 months after surgery.Conclusion: Serum FGL-1 levels were significantly decreased following LSG in patients with obesity. The preoperative serum FGL-1 levels could be a predictor of postoperative liver fibrosis improvement. Furthermore, the decreased FGL-1 levels were associated with improved liver enzymes and UA but not with bodyweight or glucolipid metabolism.