Ectopic fat: the true culprit linking obesity and cardiovascular disease?

Abstract

Obesity is a major risk factor for cardiovascular disease and its complications. However, not all fat depots share the same characteristics. Recent studies have found that ectopic rather than subcutaneous fat accumulation is associated with increased cardiometabolic risk. However, ectopic fat accumulation can be seen initially as a protective mechanism against lipotoxicity. Subsequently the adipose tissue becomes dysfunctional, thus inducing systemic metabolic alterations (through release of cytokines) or specific organ dysfunctions. The purpose of this review is to summarise the current available data on the impact of excess adiposity vs ectopic fat in the development of cardio-metabolic diseases.

The color of fat and its central role in the development and progression of metabolic diseases

“…This has led to the definition of adiposopathy, or sick fat [34]. Moreover, dysfunctional WAT is resistant to the anti-lipolytic effect of insulin, and is responsible for fatty acid overflow and the development of lipotoxicity that in turn determines alteration in glucose and lipid metabolism [35]. Studies with overfeeding did not help to clarify the impact of dysfunctional WAT.…”

“…They studied the effect of 8 weeks of excess energy and lipid intake on adipocyte size and expansion in young healthy men: lean subjects with smaller adipocytes responded with a rapidly and not protective adipocyte remodelling, and despite expansion of subcutaneous fat they developed insulin resistance and released more inflammatory markers while subjects with larger subcutaneous adipocytes had less insulin resistance and visceral fat accumulation, maybe due to reduced expandability of these cells [31]. It is likely that other factors are involved, possibly a genetic predisposition to type 2 diabetes or in general to ectopic fat deposition [3], [35], [37], [38].…”

The Role of Epicardial Obesity in the Development of Structural and Functional Remodeling of the Heart

“…Отсутствие различий подгрупп пациентов с нали-чием/отсутствием эпикардиального ожирения по величине ОТ может являться еще одним подтвержде-нием превалирующего значения локального эктопи-ческого висцерального жирового депо в патогенезе кардиального ремоделирования [14].…”

Epicardial fat thickness as a tool for predicting complicated obesity

“…Продемонстрированные в многочисленных иссле-дованиях взаимосвязи между выраженностью ЭВЖД и различными метаболическими нарушениями, показателями нейрогуморальной активности ВЖТ, параметрами кардиоваскулярного ремоделирования, а также частотой различных сердечно-сосудистых осложнений (ССО), позволили выдвинуть гипотезу о том, что не ожирение как таковое в целом, а акку-мулированный эктопический висцеральный жир является причиной увеличения риска при висцераль-ном ожирении [16], и дать начало новому этапу в изучении показателей количественной оценки ЭВЖД в качестве самостоятельных факторов кардио-васкулярного риска.…”