INS and obesity due to melanocortin 4 receptor deficiency: This assumption is supported by a study conducted by Grapentine et al. in which they demonstrated that deficiency of PE synthesizing enzyme (CTP:phosphoethanolamine cytidylyltransferase - Pcyt2) in Pcyt2+/− mice results in disrupted PE milieu with subsequent deleterious metabolic effects including enhanced lipogenesis, greater intramuscular accumulation of DAGs and triacylglycerols (TAGs), impaired insulin signaling and mounting inflammatory state in skeletal muscle, which is linked to occurrence of obesity and IR (Grapentine et al., 2023).