PTPN1 and obesity due to melanocortin 4 receptor deficiency: Although the protective role of PTP1B inhibition on inflammatory conditions such as obesity-induced diabetes, colitis [16, 48], and LPS-induced neuroinflammation (Fig. 7) has been observed, the ability of PTP1B inhibitor to protect against neurodegenerative diseases including Alzheimer’s disease, Parkinson’s disease, and multiple sclerosis remains unknown.