Increased Levels of AIM2 and Circulating Mitochondrial DNA in Type 2 Diabetes

Chronic inflammation has critical role in Type 2 diabetes (T2D), in which IL-1β contributes in insulin resistance and beta cell dysfunction. The activation of NLRP3 and AIM2 by endogens ligands, such as mtDNA can lead to the release of active form of IL-1β. To evaluate AIM2 expression and activation as well as circulating mtDNA levels in T2D patients. AIM2 expression was analyzed by flow cytometry, it's activity was assessed by measuring in vitro release of IL-1β induced by Poly (dA:dT), and mtDNA copy number was determined by quantitative real-time polymerase chain reaction. Increased percent of AIM2+ cells were detected in monocytes from patients with T2D. Moreover, increased levels of IL-1β in monocytes cultures from T2D patients compared to healthy controls were observed. Also, association between AIM2+ cells and hyperglycemia (r=0.4385, P=0.0095) and triglycerides levels (r=0.5112, P=0.002) and waist-hip ratio (r=0.4710, P=0.0049) were detected. Likewise, the mtDNA copy number was augmented in T2D patients compared to control group. The mtDNA copies number was associated with body mass index (r=0.4231, P=0.0008) and TNF-α levels (r=0.5231, P=0.0005). In addition, increased levels of IL-12p70, TNF-a, IL-10, IL-6, IL-8 and IL-1β were detected in a serum from T2D patients. These results suggest the involvement of AIM2 and mtDNA in the inflammatory process seen in T2D.