Oxidative stress and inflammatory markers in type 2 diabetic patients

Eur J Clin Invest. 2020 Jun;50(6):e13238. doi: 10.1111/eci.13238. Epub 2020 May 15.

Abstract

Background: Type 2 diabetes mellitus (T2DM) is most demanding public health problem of 21st century. Uncontrolled diabetes may cause complications affecting any part of gut from mouth to rectum presenting as vomiting, nausea, bloating, abdominal pain, constipation and diarrhoea. The aim of this study was to compare levels of oxidative stress and inflammatory markers in small intestinal bacterial overgrowth (SIBO)-positive and negative diabetic patients.

Subjects and methods: An observational analytical study was conducted on 300 T2DM (>5 years' duration) attending Diabetic Clinic. A total of 200 age- and sex-matched healthy individuals were enrolled as controls. Noninvasive glucose hydrogen breath test was used to diagnose SIBO. A total of 5 mL blood was taken. Plasma was used for measurement of inflammatory cytokines (TNF-α, IL-6 and IL-10) by ELISA. Hemolysate was used for measurement of lipid peroxidation, reduced GSH, superoxide dismutase and catalase.

Results: It was observed that constipation was present in 59.6% T2DM patients. SIBO was observed significantly higher (P < .0001) in T2DM patients than controls. Inflammatory and oxidative stress markers were significantly (P < .001) higher in diabetic and SIBO-positive patients than controls and SIBO negative. Reduced GSH was significantly (P < .05) lower whereas superoxide dismutase (SOD) and catalase antioxidant enzymes were significantly (<.05) higher in diabetic and SIBO-positive patients than controls and SIBO-negative patients.

Conclusion: From this study, it could be concluded that SIBO in T2DM patients can cause oxidative stress and inflammation. Therefore, SIBO should be taken care to prevent further damage to intestine.

Keywords: inflammatory markers; orocecal transit time; oxidative stress; small intestinal bacterial over growth; type 2 diabetes mellitus.

Publication types

  • Observational Study

MeSH terms

  • Blind Loop Syndrome / immunology
  • Blind Loop Syndrome / metabolism*
  • Breath Tests
  • Case-Control Studies
  • Catalase / metabolism*
  • Cytokines / immunology*
  • Diabetes Mellitus, Type 2 / immunology
  • Diabetes Mellitus, Type 2 / metabolism*
  • Female
  • Glutathione / metabolism*
  • Humans
  • Inflammation / immunology*
  • Interleukin-10 / immunology
  • Interleukin-6 / immunology
  • Lipid Peroxidation
  • Male
  • Middle Aged
  • Oxidative Stress*
  • Superoxide Dismutase / metabolism*
  • Tumor Necrosis Factor-alpha / immunology

Substances

  • Cytokines
  • IL10 protein, human
  • IL6 protein, human
  • Interleukin-6
  • TNF protein, human
  • Tumor Necrosis Factor-alpha
  • Interleukin-10
  • Catalase
  • Superoxide Dismutase
  • Glutathione