OBJECTIVE: Bariatric surgery is emerging as an effective method to alleviate a multitude of medical conditions associated with morbid obesity and type 2 diabetes. However, little is known about the effects and mechanisms of bariatric surgery on visceral fat inflammation and endothelial dysfunction in type 2 diabetes. We hypothesize that bariatric surgery ameliorates interferon-γ-mediated adipose tissue inflammation/oxidative stress and improves endothelial function in type 2 diabetic mice. METHODS AND RESULTS: Control mice (m Lepr(db)) and diabetic mice (Lepr(db)) were treated with either sham surgery or improved gastric bypass surgery and then were evaluated at 5, 10, 20, and 30 days to assess postsurgical effects. Surgery reduced body weight, abdominal adiposity, blood glucose level, and food intake in Lepr(db). The surgery-induced decrease in visceral adiposity was accompanied by amelioration of T-lymphocytes and macrophage infiltration, as well as reduction in the expression of interferon-γ and other inflammatory cytokines in the mesenteric adipose tissue (MAT) of Lepr(db) mice. Furthermore, surgery improved endothelium-dependent, but not endothelium-independent, vasorelaxation in small mesenteric arteries (SMA) of Lepr(db) mice. The improvement in endothelial function was largely attenuated by nitric oxide synthase inhibitor (L-NAME) incubation. Interferon-γ treatment increased the mRNA expression of tumor necrosis factor-α in the MAT of control mice and incubation of SMA of control mice with tumor necrosis factor-α caused impairment of endothelial function. Superoxide production in MAT/SMA and nitrotyrosine protein level in SMA were elevated in diabetic mice. Surgery reduced MAT/SMA oxidative stress in Lepr(db) mice. CONCLUSIONS: The amelioration of adipose tissue inflammation and the improvement of endothelial function may represent important mechanisms that result in cardiovascular benefits after bariatric surgery.
OBJECTIVE: Bariatric surgery is emerging as an effective method to alleviate a multitude of medical conditions associated with morbid obesity and type 2 diabetes. However, little is known about the effects and mechanisms of bariatric surgery on visceral fat inflammation and endothelial dysfunction in type 2 diabetes. We hypothesize that bariatric surgery ameliorates interferon-γ-mediated adipose tissue inflammation/oxidative stress and improves endothelial function in type 2 diabeticmice. METHODS AND RESULTS: Control mice (m Lepr(db)) and diabeticmice (Lepr(db)) were treated with either sham surgery or improved gastric bypass surgery and then were evaluated at 5, 10, 20, and 30 days to assess postsurgical effects. Surgery reduced body weight, abdominal adiposity, blood glucose level, and food intake in Lepr(db). The surgery-induced decrease in visceral adiposity was accompanied by amelioration of T-lymphocytes and macrophage infiltration, as well as reduction in the expression of interferon-γ and other inflammatory cytokines in the mesenteric adipose tissue (MAT) of Lepr(db) mice. Furthermore, surgery improved endothelium-dependent, but not endothelium-independent, vasorelaxation in small mesenteric arteries (SMA) of Lepr(db) mice. The improvement in endothelial function was largely attenuated by nitric oxide synthase inhibitor (L-NAME) incubation. Interferon-γ treatment increased the mRNA expression of tumor necrosis factor-α in the MAT of control mice and incubation of SMA of control mice with tumor necrosis factor-α caused impairment of endothelial function. Superoxide production in MAT/SMA and nitrotyrosine protein level in SMA were elevated in diabeticmice. Surgery reduced MAT/SMA oxidative stress in Lepr(db) mice. CONCLUSIONS: The amelioration of adipose tissue inflammation and the improvement of endothelial function may represent important mechanisms that result in cardiovascular benefits after bariatric surgery.
Authors: Noyan Gokce; Joseph A Vita; Marie McDonnell; Armour R Forse; Nawfal Istfan; Maria Stoeckl; Izabella Lipinska; John F Keaney; Caroline M Apovian Journal: Am J Cardiol Date: 2005-01-15 Impact factor: 2.778
Authors: Marta Focardi; Gregory M Dick; Andrea Picchi; Cuihua Zhang; William M Chilian Journal: Am J Physiol Heart Circ Physiol Date: 2007-01-12 Impact factor: 4.733
Authors: Luis Alberto Vázquez; Fernando Pazos; José Ramón Berrazueta; Carlos Fernández-Escalante; María Teresa García-Unzueta; Julio Freijanes; José Antonio Amado Journal: J Clin Endocrinol Metab Date: 2004-10-26 Impact factor: 5.958
Authors: Samuel Klein; Luigi Fontana; V Leroy Young; Andrew R Coggan; Charles Kilo; Bruce W Patterson; B Selma Mohammed Journal: N Engl J Med Date: 2004-06-17 Impact factor: 91.245