Association of circulating proinflammatory marker, leucine-rich-α2-glycoprotein (LRG1), following metabolic/bariatric surgery

Background: Obesity confers substantial excess risk for morbidity and mortality, especially for type 2 diabetes (T2D). Leucine-rich-alpha 2-glycoprotein 1 (LRG1), a novel proinflammatory factor, was recently reported to be higher in patients with T2D with complications of peripheral arterial disease. Association of LRG1, obesity, and weight loss is unknown. We examined whether plasma LRG1 is associated with obesity in health screening participants and if it predicts future weight loss in morbidly obese patients after metabolic/bariatric surgery. Methods: Cohort 1 was a cross-sectional study from a Health Screening program (n = 616) in a tertiary hospital. Cohort 2 was a prospective study of morbidly obese patients (n = 231) who underwent metabolic/bariatric surgery with follow-up weight measurements. Anthropometric data, baseline fasting glucose, plasma adiponectin, high sensitivity C-reactive protein (HsCRP), and LRG1 were measured. Postsurgery blood, after metabolic/bariatric surgery, were available for LRG1 and HsCRP measurements in 57 patients. Results: In the group with highest tertile of LRG1, body mass index (BMI), waist circumference, and HsCRP were significantly higher, while total cholesterol, high-density lipoprotein, low-density lipoprotein, and adiponectin were lower than tertiles 1 and 2. Generalized linear model analysis showed that female gender (P < .0001), non-Chinese ethnicity (P < .019), and higher HsCRP (P < .0001) levels were independent and significant determinants of higher plasma LRG1 levels. After adjustment for age, gender, ethnicity, and baseline BMI, female gender (P = .020), higher presurgery BMI (P = .001), and lower presurgery LRG1 (P = .002) remained statistically significant predictors for greater weight loss. Plasma LRG1 increased significantly [from 28.2 (21.9-36.8) to 34.9 (22.6-49.5)] g/mL (P = .003) within 1.5 months, after metabolic/bariatric surgery. Conclusions: Our study demonstrates that LRG1 level is positively associated with obesity and a lower level of plasma LRG1 predicts weight loss in metabolic/bariatric surgery. Our novel findings suggest LRG1, itself or in combination with other known factors, is a potential biomarker of inflammation and obesity.