Serum Asprosin Levels and Bariatric Surgery Outcomes in Obese Adults

Background/objectives: Asprosin is a novel fasting-induced glucogenic and orexigenic protein hormone. The clinical function of asprosin in obesity is currently unknown. This study investigated the association between asprosin abundance and the outcome of bariatric surgery.

Subjects/methods: Patients with body mass index more than 35 kg/m were recruited for the Obesity and Clock for Elegant Aging Registry in 2011-2016. Body weight changes, blood sugar, and asprosin were assessed in 117 patients receiving bariatric surgery and 57 non-obese subjects as normal control. Primary outcomes of excess weight loss percentage at 6 months after bariatric surgery were determined at follow-up.

Results: Asprosin levels were significantly higher in obese patients than in non-obese subjects (2360 ± 5094 vs. 307 ± 832 ng/ml, p < 0.0001). Multivariate analyses showed a significant association of asprosin abundance with excess body weight loss percentage at 6 months after surgery (p < 0.0001). After adjusted for age, sex, smoking, HbA1c, cholesterol, and triglyceride, serum asprosin level was the only independent predictor of 6 months excess weight loss percentage after bariatric surgery. Asprosin levels decreased significantly 6 months after bariatric surgery (162.2 ± 169.1 ng/ml). Furthermore, there was no association between asprosin and serum glucose levels in our study.

Conclusion: This study provides novel evidence that higher asprosin concentrations before bariatric surgery were associated with the weight reduction magnitude at 6 months after surgery. Further studies are warranted to investigate whether asprosin has direct functions to modulate body weight regulation in humans after bariatric surgery.