For instance, several cross-sectional studies, including Zhang et al. [66] reported that serum Nrg4 levels were decreased and negatively correlated with FPG, fasting insulin, and HOMA-IR in participants with T2DM, while studies by Yan and co-workers [67,68] found that low plasma Nrg4 levels were inversely correlated with proinflammatory mediators hs-CRP and white blood cell count but positively correlated with HDL-c. This evidence concerns the gene NRG4 and type 2 diabetes mellitus.