Stefano Benedini^1,2*, Isabella Fermo³, Andrea Caumo¹, Ileana Terruzzi⁴, Livio Luzi^1,2

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¹ Department of Biomedical Sciences and Health, Università degli Studi di Milano, Milan, Italy.
² Metabolism Research Center, IRCCS Policlinico San Donato, Milan, Italy.
³ Division of Immunology, Transplantation & Infectious disease San Raffaele Scientific Institute, Milan, Italy.
⁴ Diabetes Research Institute, Metabolism, Nutrigenomics and Cellular Differentiation Unit, San Raffaele Scientific Institute, Milan, Italy.
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Abstract: Objectives: In the last decade gut microbial diversity was associated with the pathogenesis of obesity in humans. Plasma citrulline was a simple and accurate biomarker for the severity of intestinal failure and was associated with short bowel syndrome and alteration of gut permeability, being developed as an alternative to D-xylose tolerance test for the diagnosis of an abnormal small intestinal absorption of nutrients. This study was performed to ascertain whether obesity might be associated with dysregulation of epithelial gut function. Methods: Fifteen obese individuals (5 M/10 F; BMI 37.4 ± 6.1 Kg/m2; 42 ± 6 yrs) and 15 healthy gender- and age-matched controls (6 M/9 F BMI: 22.7 ± 2.1 Kg/m2; 39 ± 7 yrs) underwent D-xylose load (25 g) and plasma citrulline, plasma insulin, glucose and lipid profile testing. Results: Plasma citrulline was significantly lower in the obese group (p = 0.045) with respect to controls, whilst total cholesterol, LDL and trygliceri- des concentration, insulin level and HOMA-IR were significantly higher in obese patients. In contrast, after D-xylose load no difference in serum xylose was found between the two groups (p = ns). Conclusions: Obese patients show a decreased citrulline concentration with respect to lean subjects. Since citrulline is a known marker of intestinal health, alterations in the gut epithelium are likely to be associated with the obesity syndrome. We propose to measure citrulline level in obese patients on a routine basis.

Keywords: Citrulline, Obesity, HOMA-IR, Gut

Cite this paper: Benedini, S. , Fermo, I. , Caumo, A. , Terruzzi, I. , Luzi, L. (2015) Plasma Citrulline: A New Marker of Gut Epithelium Alteration in Obese Patients?. Journal of Diabetes Mellitus, 5, 233-237. doi: 10.4236/jdm.2015.54028.

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