Type 2 diabetes is associated with decreased PGC1α expression in epicardial adipose tissue of patients with coronary artery disease

Abstract

BackgroundAlthough recent studies indicate that epicardial adipose tissue expresses brown fat-like genes, such as PGC1α, UCP1 and PRDM16, the association of these genes with type 2 diabetes mellitus (DM2) in coronary artery disease (CAD) remains unknown.MethodsPGC1α, UCP1, and PRDM16 mRNAs expression levels were measured by real-time PCR in epicardial and thoracic subcutaneous adipose tissue from 44 CAD patients (22 with DM2 [CAD-DM2] and 22 without DM2 [CAD-NDM2]) and 23 non-CAD patients (NCAD).ResultsThe CAD-DM2 patients had significantly lower PGC1α and UCP1 expression in epicardial adipose tissue than the CAD-NDM2 and NCAD patients. However, PGC1α and UCP1 mRNA trended upward in subcutaneous adipose tissue from CAD-DM2 patients. At multiple regression analysis, age, body mass index, left ventricular ejection fraction, UCP1 expression of epicardial adipose tissue and diabetes came out to be independent predictors of PGC1α levels. Epicardial adipose tissue PGC1α expression was dependent on the number of injured coronary arteries and logistic regression analysis showed that PGC1α expression in epicardial adipose tissue could exert a protective effect against coronary lesions.ConclusionsDM2 is associated with decreased expression of PGC1α and UCP1 mRNA in epicardial adipose tissue of patients with CAD, likely reflecting a loss of brown-like fat features. Decreased expression of PGC1α in human epicardial adipose tissue is associated with higher prevalence of coronary lesions.

Ultrasound Histogram Analyses of Epicardial Adipose Tissue

“…However, there are some data showing that EAT contains BAT as well. Published studies or studies focused on the identification of EAT as brown-like tissue used gene expression such as PGC1α, UCP1 and PRDM16 mRNAs where adipose tissue was collected invasively usually during patient´s operation [18,19,20]. Moreover, some of these invasive studies showed that, depending on the presence of different type of adipose tissue, different cardiovascular and metabolic risks are present in patients.…”

“…Moreover, some of these invasive studies showed that, depending on the presence of different type of adipose tissue, different cardiovascular and metabolic risks are present in patients. Moreno-Santos et al [18] showed that patients with type 2 diabetes and coronary artery disease exhibited a loss of brown-like fat features. This was also associated with higher prevalence of coronary lesions.…”

“…Since then more studies are available [34,35,36,37]. Besides the MRI, some other non-invasive investigation methods like 18 Ffluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) for the BAT identification were used [20,21,22].…”

“…The EAT is considered as a special form of visceral fat reflecting intra-abdominal fat deposition [15,16], however, recently it has been described as brown adipose tissue [17]. Investigators who confirmed that epicardial adipose tissue has some features of BAT used invasive methods primarily represented by gene expression in adipose tissue [17,18,19]. Despite the fact that non-invasive methods are quite expensive for clinical practice the methods such as magnetic resonance imaging (MRI) or computed tomography (CT) scanning for detection of the BAT [20,21,22] have been performed.…”

Looking beyond ectopic fat amount: A SMART method to quantify epicardial adipose tissue density

“…10,11 This brite phenotype seems to decrease with age, diabetes mellitus and the severity of CAD. 12,13 There has been growing interest in the past decade in the non-invasive imaging of EAT volume as a predictor of future coronary events. 14 In the Heinz Nixdorf recall study, which included more than 4000 middle-aged participants, EAT volume measured by computed tomography (CT), was significantly associated with coronary events over the following 8 years.…”