Obesity
The present study is the first study to compare the serum zonulin levels between obese and non-obese children. We demonstrated that serum zonulin levels were higher in obese children when compared to healthy children, which may play a role in the pathogenesis of obesity and related metabolic disturbances.
Obesity is associated with systemic microinflammation due to the release of proinflammatory peptides in visceral adipose tissue. Systemic microinflammation in obesity is the major cause in the pathogenesis of metabolic disorders such as insulin resistance (IR), dyslipidemia, type 2 diabetes. Recent evidence suggests a possible role of intestinal barrier dysfunction from releasing proinflammatory peptides in obesity.
Recent studies which report an increase in intestinal permeability and absorption together with a decrease in intestinal motility in patients with metabolic disorders indicate a link between intestinal barrier dysfunction and metabolic disorders.
Intestinal TJ dysfunction and upregulation of zonulin were found to be the primary defects in these diseases. Circulating zonulin levels are considered to be a useful marker of intestinal permeability. Recently, higher circulating zonulin levels were reported in obese adult subjects as compared to the non-obese and also in adults with glucose intolerance as compared to those with normal glucose tolerance.
Consequently, the development of inflammation in the intestinal microbiota is suggested to increase zonulin expression
In conclusion, zonulin expression is thought to be regulated by subclinical systemic inflammation as well as by local intestinal inflammation. What this means is that intestinal permeability is increased in inflamed individuals and obese people are more inflamed.
In the present study, we found a significant positive correlation between serum zonulin concentrations and leptin levels in obese individuals.
