Date Published: January 30, 2018
Publisher: Public Library of Science
Author(s): Nariman Moradi, Reza Fadaei, Solaleh Emamgholipour, Elham Kazemian, Ghodratollah Panahi, Siamak Vahedi, Lotfolah Saed, Soudabeh Fallah, Jonathan M. Peterson.
C1q/TNF-related protein 9 (CTRP9) is a paralogue of adiponectin with known favorable effects on lipid and glucose metabolism. A potential role of CTRP9 for regulation of endothelium function has been suggested by previous studies. However, no studies have examined the relation between serum CTRP9 levels and adhesion molecules in patients with type 2 diabetes mellitus (T2DM) and coronary artery disease (CAD). The present study was conducted on 337 subjects who underwent coronary angiography and were categorized into four groups according to the presence of CAD and T2DM (control, CAD, T2DM and CAD+T2DM). Serum levels of CTRP9, adiponectin, sICAM-1, sVCAM-1, sE-Selectin, IL-6 and TNF-α were measured. It was found that the circulating CTRP9 levels were independently associated with increased risk of CAD and T2DM in addition to elevated levels of serum CTRP9 in CAD, T2DM and CAD+T2DM groups. A significant association of serum CTRP9 levels with adhesion molecules in CAD and T2DM patients as well as serum TNF-α levels in CAD individuals was noted. A significant relation between the circulating levels of CTRP9 and HOMA-IR in T2DM subjects was also observed. The results revealed increased circulating levels of CTRP9 in T2DM and CAD individuals which suggests a compensatory response to insulin resistance, inflammatory milieu and endothelial dysfunction; however, more studies are needed to confirm this.
Adipose tissue is a highly active endocrine organ that is responsible for the synthesis and secretion of several hormones, such as bioactive molecules known as adipokines . In recent years, considerable research has been devoted to understanding the biology of adipokines and their potential role in obesity-related diseases such as diabetes and cardiovascular disease (CVD) [2,3]. Adipokines have been identified as having diverse functional roles in lipid and glucose metabolism and in inflammation, along with the pathogenic processes of many diseases [4,5].
Anthropometric and clinical characteristics of the study participants are presented in Table 1. No significant differences in age, sex or BMI were observed between groups. The number of smokers and individuals taking statins and antihypertensive medications were higher in the case groups than in the control. Anti-hyperglycemic medications were used only by T2DM patients (T2DM and CAD+T2DM groups). Details of medication use are given in S1 Table. Higher SBP, DBP and FBS values were found in the CAD+T2DM group compared to the control. The highest level of FBS and the lowest levels of insulin and the HOMA-IR index were observed in the control group. In addition, compared to T2DM and CAD+T2DM groups, CAD individuals had lower HOMA-IR indexes. Furthermore, the results of post hoc analysis showed a significant difference in circulating levels of TG, TC, LDL-C, HDL-C, ALT and AST between the case and control groups.
The findings of the present study revealed that circulating CTRP9 levels were associated with an increased risk of T2DM and CAD. The associations between CTRP family members and cardio-metabolic abnormalities have been documented by previous studies [24–26]. Interestingly, we found an independent association of CTRP9 levels with soluble adhesion molecules in patients with CAD and T2DM. These results indicate that serum levels of CTRP9 were elevated in CAD and T2DM patients. Preceding studies showed increased levels of serum CTRP9 in obesity and its attendant health risks [8,18–20], while decreased serum levels of CTRP9 was reported in CAD patients . These observed discrepancies may have resulted from differences such as non-CAD subject selection/exclusion criteria and ethnicities between studies.