Correlation of vascular structural changes in a cadaveric model and obesity-related cardiovascular non-communicable diseases

Abstract

Introduction: Carrying excess body weight is a vital risk factor for obesity-related chronic diseases affecting blood vessels. Obesity influences cardiovascular non-communicable diseases (NCDs) via vascular structural changes, which involve alterations in lipids, blood pressure, coagulation, fibrinolysis, and inflammation, leading to endothelial dysfunction due to vascular remodeling and stiffness. Small peripheral vessels are the first to be impacted; however, it is unclear whether this change is followed by microscopic changes in the aorta.

Objectives: To determine the correlation of vascular structure with the incidence of NCDs and subcutaneous fat thickness and to study micro-scale changes in vascular structure, especially concerning collagen in the aorta, using a cadaveric model.

Methods: Twenty-four cadaveric models were classified into a control group and an NCD group. The subcutaneous fat thickness was measured on the arm, anterior abdomen, and thigh. The aorta was collected and stained with hematoxylin, eosin, and Masson's trichrome for collagen evaluation. The vessel thickness was morphometrically analyzed. Scanning electron microscopy was performed to identify the extracellular matrix organization in the vessel.

Results: Disorganization of the extracellular matrix and fragments of the vascular wall were found in the NCDs group. The tunica intima of the NCDs group represented endothelial dysfunction with macrophage foam cells. The thickness of the tunica intima of the NCDs group slightly increased without being significantly different compared to control group with 144.63 ± 124.38 µm and 105.60 ± 27.49 µm, respectively. However, the thickness of tunica media of the NCDs group significantly decreased compared to control group with 956.58 ± 27.80 µm and 1167.43 ± 48.6 µm, respectively. Collagen deposits in the aortic wall significantly increased by 15% in the NCDs group especially in tunica media by 17.4% compared to control. The results showed a correlation between the amount of collagen fiber and subcutaneous fat on the thigh.

Conclusion: There was a change toward irregular microstructural patterns and increased collagen fibers in NCDs. In addition, there was a correlation between collagen fiber density and the subcutaneous fat thickness of the thigh in cadavers with a history of NCDs.

Keywords: Aortic thickness; collagen; non-communicable diseases; subcutaneous fat.