PRTN3 and obesity due to melanocortin 4 receptor deficiency: However, in recent years, several studies have shown that NE and PR3 are important drivers of chronic inflammation leading to metabolic disturbances in mouse models for obesity-induced insulin resistance, type 2 diabetes and NAFLD (Mansuy-Aubert et al. 2013; Toonen et al. 2016; Talukdar et al. 2012).