Adiposity and inflammation markers explain mostly part of the plasma zonulin variation in Brazilian adults with overweight/obesity: A cross-sectional analysis from Brazilian nuts study

Objective: This study evaluated intestinal permeability according to plasma zonulin and its association with adiposity, inflammation, cardiometabolic risk, liver function, and intestinal health markers in adults with overweight/obesity.

Methodology: This study is a cross-sectional analysis using baseline data from the Brazilian Nut Study, which involved 123 participants (93 women, age 33.2 ± 8.58 years, BMI 33.9 ± 4.30kg/m2). Subjects were divided into quartiles according to plasma zonulin, assessed by Elisa. Cytokines were assessed by flow cytometry; anthropometric measurements were collected by standard procedure and body composition was assessed by DXA. SCFA analysis was performed by high-performance liquid chromatography, and fecal pH, by a pH meter. Linear regression models were performed (α<5 %).

Results: Participants included in the last quartile of plasma zonulin had higher values of body fat (%), pro-inflammatory cytokines (CRP, IL-1). According to the multivariate regression model, each one-unit increased in body fat, CRP, IL-12p70, IL-6 and IL-8 resulted correspondingly in an increment of 0.42, 0.14, 0.192, 0.250 and 0.312 ng/ml in plasma zonulin, respectively. Conversely, a one-unit decreased in IL-10 led to an increase of 0.40 ng/ml in plasma zonulin.

Conclusion: Intestinal permeability assessed by plasma zonulin is associated with adiposity, subclinical inflammation and reduced serum HDL levels adults with overweight/obesity, while adiposity and inflammation markers are independent factors for plasma zonulin variation.