Insulin Resistance is Associated with Gut Permeability Without the Direct Influence of Obesity in Young Adults

Objective: Recent findings have associated insulin resistance and obesity with increased gut permeability. However, it still remains unclear whether obesity may be the underlining factor for the association between gut permeability and insulin resistance. This study investigated the relationship between gut permeability, measures of obesity, and markers of insulin resistance in young adults. Materials and Methods: A cross-sectional quantitative study which enrolled 151 young South African adults was conducted. Anthropometric measurements were performed to assess obesity. Adiponectin, leptin, and zonulin, a marker for gut permeability, were assayed. Insulin and fasting glucose were assayed and used to determine insulin resistance (HOMAIR), insulin sensitivity (%S) and beta cell function (%B). Results: Decreased adiponectin and increased leptin were associated (p<0.05) with obesity. HOMA-IR inversely correlated (p<0.05) with adiponectin but positively with leptin to adiponectin (Lept/ADP) ratio (p<0.05) in females. Markers of insulin resistance were not associated (p>0.05) with obesity. Overweight/obese (0/0) females had a significantly (p<0.01) higher zonulin concentration than lean females. Zonulin positively associated (p<0.05) with body mass index and visceral fat, as well as with HOMA-IR and insulin concentration. Lept/ADP ratio, an inflammatory marker, was associated with risk of insulin resistance. Increased insulin, a maker for insulin resistance, was associated with risk of gut permeability. Conclusion: Insulin resistance was associated with gut permeability without a direct influence by obesity in young adults. The lack of relationship between obesity and insulin resistance was possibly mediated by the contribution of obesity to gut permeability. This finding suggests that gut permeability may be a potential independent risk factor for the development of insulin resistance in healthy obese young adults.