Investigation of the immunometabolic roles of IRF5, IRF7, and FOXO1 transcription factors in macrophages and adipocytes in obesity and type-2 diabetes

The prevalence of type-2 diabetes (T2D) in adult and adolescent Kuwaiti populations is alarmingly high and the national health priorities necessitate to find targets for effective disease control. The molecular pathway research is a cutting edge domain and promising approach to identify novel biomarkers or therapeutic targets. Obesity-induced chronic low-grade inflammation called metaflammation is pivotal in inducing insulin resistance and causing T2D. To this effect, diverse roles of transcription factors such as IRF5, IRF7, and FOXO1 are well elucidated in the context of adaptive/innate immunity, DNA damage response, and apoptosis; however, their roles in metaflammation, including pancreatic islet inflammation and insulin resistance, are unclear. Herein, we seek to investigate the molecular mechanisms that regulate expression and activity of IRF5, IRF7, and FOXO1 in macrophages and adipocytes in obesity/T2D and to understand how they cause immunometabolic deregulation at the cellular and organismal level. Our preliminary data support such a role for IRF5 which we hypothesize goes beyond to include IRF7 and FOXO1 as well. Initially, we will assess expression/activities, and upstream regulators of IRF5/7 and FOXO1, in monocytes/macrophages and adipocytes from 57 obese, 40 overweight, and 19 lean individuals with or without T2D. Next, the expression and activity changes following loss or overexpression of IRF5, IRF7 and FOXO1 will be studied in vitro using 3T3L1 and RAW264.7 cell lines as well as human adipocyte and macrophage cell lines. Insulin resistance will be measured by glucose uptake assays. Gene targets in macrophages/adipocytes will be identified using RNA-Seq, candidate proteins will be analyzed by MALDI-TOF and data will be confirmed by qRT-PCR and Western blotting, respectively. These studies are expected to define the immunometabolic role of these transcription factors in insulin resistance/T2D and have a potential to identify novel markers of prognostic or targets of therapeutic significance.