Protein tyrosine phosphatase 1B inhibitory properties of seco-cucurbitane triterpenes obtained from fruiting bodies of Russula lepida

AbstractThe known seco-cucurbitane triterpene, (24E)-3,4-seco-cucurbita-4,24-diene-3,26,29-trioic acid (1), has been isolated as a potent protein tyrosine phosphatase (PTP) 1B inhibitor together with a new analogue, (24E)-3,4-seco-cucurbita-4,24-diene-3-hydroxy-26,29-dioic acid (2), from the fruiting bodies ofRussula lepida. Further evaluation of their biological properties against PTPs revealed that compound1 inhibited T-cell PTP activity similarly to PTP1B and exhibited moderate selectivity against PTP1B overvaccinia H-1-related phosphatase. Moreover, the in vitro growth inhibitory effects of1 and2 against three human cancer cell lines were examined in order to evaluate cell-based efficacy. However, neither1 nor2 enhanced insulin-stimulated p-Akt levels at non-cytotoxic concentrations.
Source: Journal of Natural Medicines - Category: Drugs & Pharmacology Source Type: research