OBJECTIVE: Obesity is associated with oxidative stress and inflammation. We hypothesized that the pro-inflammatory state in obesity may result in spontaneous activation and, hence, increased generation of reactive oxygen species (ROS) and integrin expression in the circulating leukocytes. METHODS: Flow cytometry was used to determine integrin expression (immunostaining) as well as superoxide and hydrogen peroxide productions (fluorescent probes) in the peripheral blood and splenic leukocyte of 24-week-old male obese normotensive and not-as-yet diabetic Zucker rats (n = 6) and their lean counterparts (n = 6). RESULTS: Obese rats had hyperlipidemia and normal arterial pressure, plasma glucose, and creatinine concentrations. Nevertheless, obese rats exhibited increased hydrogen peroxide production by circulating and splenic CD4+ and CD8+ T lymphocytes and by splenic macrophages. This was accompanied by up-regulations of CD11a expression in the peripheral blood and splenic CD4+ T cells, CD11b in circulating macrophages, and CD11a and CD18 in circulating granulocytes. CONCLUSION: The study revealed direct evidence of spontaneous leukocyte activation and increased ROS generation by T lymphocytes and monocytes in the peripheral blood of obese Zucker rats before the development of diabetes or hypertension. These findings illustrate the link between obesity, oxidative stress, and inflammation.
OBJECTIVE:Obesity is associated with oxidative stress and inflammation. We hypothesized that the pro-inflammatory state in obesity may result in spontaneous activation and, hence, increased generation of reactive oxygen species (ROS) and integrin expression in the circulating leukocytes. METHODS: Flow cytometry was used to determine integrin expression (immunostaining) as well as superoxide and hydrogen peroxide productions (fluorescent probes) in the peripheral blood and splenic leukocyte of 24-week-old male obese normotensive and not-as-yet diabetic Zucker rats (n = 6) and their lean counterparts (n = 6). RESULTS:Obeserats had hyperlipidemia and normal arterial pressure, plasma glucose, and creatinine concentrations. Nevertheless, obeserats exhibited increased hydrogen peroxide production by circulating and splenic CD4+ and CD8+ T lymphocytes and by splenic macrophages. This was accompanied by up-regulations of CD11a expression in the peripheral blood and splenic CD4+ T cells, CD11b in circulating macrophages, and CD11a and CD18 in circulating granulocytes. CONCLUSION: The study revealed direct evidence of spontaneous leukocyte activation and increased ROS generation by T lymphocytes and monocytes in the peripheral blood of obese Zucker rats before the development of diabetes or hypertension. These findings illustrate the link between obesity, oxidative stress, and inflammation.
Authors: Peter Horvath; Stacy R Oliver; Goutham Ganesan; Frank P Zaldivar; Shlomit Radom-Aizik; Pietro R Galassetti Journal: J Investig Med Date: 2013-08 Impact factor: 2.895