title: Effects of weight loss on structural and functional alterations of subcutaneous small arteries in obese patients.
abstract: Structural alterations of subcutaneous small resistance arteries, as indicated by an increased media:lumen ratio, are frequently present in hypertensive and/or diabetic patients and may represent the earliest alteration observed. In addition, media:lumen ratios of small arteries have a strong prognostic significance. However, no data are available about the structure of small resistance arteries of obese patients, particularly after weight loss. We have investigated 27 patients with severe obesity. Twelve of them were normotensive, and 15 were hypertensive. All of the obese patients underwent bariatric surgery. We compared results obtained with those observed in 13 normotensive lean controls and in 13 hypertensive lean patients. All of the subjects and patients underwent a biopsy of subcutaneous fat during surgical intervention. In 8 obese patients, a second biopsy was obtained after consistent weight loss, during a surgical intervention for abdominoplasty. Subcutaneous small resistance arteries were dissected and mounted on a wire myograph, and structural parameters were measured. A concentration-response curve to acetylcholine was performed to evaluate endothelial function. Obese patients, independent from the presence of hypertension, show the presence of an increased media:lumen ratio and media cross-sectional area, together with an impaired endothelial-dependent vasodilatation. After surgical correction of obesity and consistent weight loss, a significant improvement of microvascular structure and of some oxidative stress/inflammation markers were observed. In conclusion, our data suggest that the presence of obesity is associated with structural alterations of subcutaneous small resistance arteries, mainly characterized by hypertrophic remodeling. Weight loss may improve microvascular structure.
authors.affiliation: Department of Medical and Surgical Sciences, University of Brescia, c/o 2 Medicina Spedali Civili di Brescia, Piazza Spedali Civili 1, 25100 Brescia, Italy.
authors.forename: Carolina
authors.initials: C
authors.lastname: De Ciuceis
authors.forename: Enzo
authors.initials: E
authors.lastname: Porteri
authors.forename: Damiano
authors.initials: D
authors.lastname: Rizzoni
authors.forename: Claudia
authors.initials: C
authors.lastname: Corbellini
authors.forename: Elisa
authors.initials: E
authors.lastname: La Boria
authors.forename: Gianluca E M
authors.initials: GE
authors.lastname: Boari
authors.forename: Annamaria
authors.initials: A
authors.lastname: Pilu
authors.forename: Francesco
authors.initials: F
authors.lastname: Mittempergher
authors.forename: Ernesto
authors.initials: E
authors.lastname: Di Betta
authors.forename: Claudio
authors.initials: C
authors.lastname: Casella
authors.forename: Riccardo
authors.initials: R
authors.lastname: Nascimbeni
authors.forename: Claudia Agabiti
authors.initials: CA
authors.lastname: Rosei
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Ruggeri
authors.forename: Luigi
authors.initials: L
authors.lastname: Caimi
authors.forename: Enrico Agabiti
authors.initials: EA
authors.lastname: Rosei
mesh_terms: D000328:Adult; D001160:Arterioles / Q000473:pathology / Q000503:physiopathology*; D001706:Biopsy; D001794:Blood Pressure / Q000502:physiology; D015992:Body Mass Index; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009213:Myography / Q000379:methods; D009767:Obesity, Morbid / Q000150:complications / Q000503:physiopathology* / Q000534:rehabilitation; D011379:Prognosis; D012189:Retrospective Studies; D040521:Subcutaneous Tissue / Q000098:blood supply*; D014655:Vascular Resistance / Q000502:physiology*; D015431:Weight Loss