PTP1B inhibitors for type 2 diabetes treatment: a patent review (2011 - 2014).

INTRODUCTION: Protein tyrosine phosphatase 1B (PTP1B) plays an important role in the negative regulation of insulin signal transduction pathway and has emerged as novel therapeutic strategy for the treatment of type 2 diabetes. PTP1B inhibitors enhance the sensibility of insulin receptor (IR) and have favorable curing effect for insulin resistance-related diseases. A large number of PTP1B inhibitors, either synthetic or isolated as bioactive agents from natural products, have developed and investigated for their ability to stimulate insulin signaling. AREAS COVERED: This review includes an updated summary (2011 - 2014) of PTP1B inhibitors that have been published in patent applications, with an emphasis on their chemical structure, mode of action and therapeutic outcomes. The usefulness of PTP1B inhibitors as pharmaceutical agents for the treatment of type 2 diabetes is also discussed. EXPERT OPINION: PTP1B inhibitors show beneficial effects to enhance sensibility of IR by restricting the activity of enzyme and have favorable curing effects. However, structural homologies in the catalytic domain of PTP1B with other protein tyrosine phosphatases (PTPs) like leukocyte common antigen-related, CD45, SHP-2 and T-cell-PTP present a challenging task of achieving selectivity. Thus, for therapeutic application of PTP1B inhibitors, highly selective molecules exhibiting desired effects without side effects are expected to find clinical application.