Objective: The aim of this study was to investigate the effects of high glucose (HG) on inflammation in HepG2 cells. Methods: The molecular mechanisms linking HG to inflammation was assessed in HepG2 cells exposed to HG (33 mM). Results: The results showed that HG significantly enhanced TNF-α, IL-6 and PAI-1 expression in HepG2 cells. Increased expression of cytokines was accompanied by enhanced phosphorylation of JNK, P38, ERK and IKKα/IKKβ. In addition, JNK, ERK, P38 and NF-kB inhibitors could significantly attenuate HG-induced expression of TNF-α, IL-6 and PAI-1. Furthermore, HG could promote the generation of reactive oxygen species (ROS), while N-acetyl cysteine, a ROS scavenger, had an inhibitory effect on the expression of TNF-α, IL-6 and PAI-1 in HG-treated cells. Conclusions: Our results indicated that HG-induced inflammation is mediated through the generation of ROS and activation of the MAPKs and NF-kB signalling pathways in HepG2 cells.

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.

Background: Recently, much attention has been paid to the role of circulating microRNAs (miRNAs) as novel biomarkers for various diseases. The aim of this study was to investigate the level of a subset of miRNAs in serum samples of the diabetic and healthy subjects. Methods: Forty two healthy and 45 T2D subjects participated in this study. Serum miR-21, miR-126, and miR-146a levels were measured using real-time PCR. Results: There was no significant difference in the serum level of miR-21, miR-126, and miR-146a between the diabetic and non-diabetic groups. The level of miR-21 in obese non-diabetic and diabetic subjects was significantly lower than lean subjects. Correlation analyses in non-diabetic and diabetic groups revealed a significant negative correlation between the amount of miR-21 and body mass index, waist circumference, insulin, and HOMA-IR levels. Conclusions: A reduced level of miR-21 might associate with obesity and its related metabolic traits such as hyperinsulinaemia.