Inhibition of protein tyrosine phosphatase 1B by lupeol and lupenone isolated from Sorbus commixta

Abstract

Protein tyrosine phosphatase 1B (PTP1B) appears to be an attractive target for the development of new drugs for type 2 diabetes and obesity. In our preliminary test, a MeOH extract of the stem barks of Sorbus commixta Hedl. (Rosaceae) showed strong PTP1B inhibitory activity. Bioassay-guided fractionation of the MeOH extract resulted in the isolation of two lupane-type triterpenes, lupenone (1) and lupeol (2). Compounds 1 and 2 inhibited PTP1B with IC(50) values of 13.7 +/- 2.1 and 5.6 +/- 0.9 microM, respectively. Kinetic studies revealed that both the compounds 1 and 2 are non-competitive inhibitors of PTP1B that decrease V(max) values with no effect on K(m) values.

Antihyperglycemic Activity of Banana (Musa nana Lour.) Peel and Its Active Ingredients in Alloxan-Induced Diabetic Mice

“…According to reports, lupenone can inhibit α -glucosidase ( α -Glu) and protein tyrosine phosphatase 1B (PTP1B) activity in vitro [31,32], the two enzymes are associated with anti-diabetic, and recently study has found that lupenone has the anti-diabetic activity in diabetic sprague-dawley rats [33]. In this study, the results clearly showed that lupenone had a significantly antihyperglycemic activity in alloxan-induced diabetic mice with no animal deaths during the experiment.…”

RP-HPLC Characterization of Lupenone and β-Sitosterol in Rhizoma Musae and Evaluation of the Anti-Diabetic Activity of Lupenone in Diabetic Sprague-Dawley Rats

“…Lupenone and β-sitosterol are likely the primary bioactive constituents responsible for the therapeutic efficacies of Rhizoma Musae [11,12,17]. Managing the active ingredients in herbs may be a feasible approach to control the therapeutic qualities of medicinal herbs [18,19].…”

“…Current studies have shown that lupenone and β-sitosterol possess multiple pharmacological activities. For example, in vitro studies have found that lupenone stimulates melanogenesis in B 16 murine melanoma cells [10], as well as inhibits α-glucosidase (α-Glu) and protein tyrosine phosphatase 1B (PTP1B) activities [11,12], Furthermore, lupenone inhibits adipogenic differentiation via downregulation of peroxisome proliferator-activated receptor PPARγ expression in 3T3-L1 cells [13]. Additionally, previous studies have reported that β-sitosterol inhibits the growth of HT-29 human colon cancer cells and induces apoptosis of LNCaP human prostate cancer cells in vitro [14,15].…”

Antidiabetic and antiplatelet aggregation study of various methanol fractions of Nymphaea stellata Willd. leaves

“…5). Oleanolic acid [28], betulinic acid [29] and lupeol [30] has been previously reported for PTP1B inhibition activity. The activity of UPFME may be due to the synergistic action of oleanolic acid, betulinic acid and lupeol.…”