A potential human hepatocellular carcinoma inhibitor from Bauhinia purpurea L. seeds: from purification to mechanism exploration

Abstract

A 20-kDa Kunitz-type trypsin-chymotrypsin inhibitor, Bauhinia purpurea trypsin inhibitor (BPLTI), has been isolated from the seeds of B. purpurea L. by using liquid chromatography procedures that involved ion exchange chromatography on Sp-Sepharose and Mono S and gel filtration on Superdex 75. BPLTI demonstrated protease inhibitory activities of 7226 BAEE units/mg and 65 BTEE units/mg toward trypsin and α-chymotrypsin, respectively. BPLTI was relatively thermal (0-60°C) and pH (3-10) stable and its activity could be decreased by dithiothreitol treatment. BPLTI exhibited a wide spectrum of anti-proliferative and pro-apoptotic activities especially on human hepatocellular carcinoma Hep G2 cells. However, it was devoid of a significant antiproliferative effect on immortal human hepatic WRL 68 cells. We show here that BPLTI stimulates apoptosis in Hep G2 cells, including (1) evoking DNA damage including the production of chromatin condensation and apoptotic bodies; (2) induction of cell apoptosis/necrosis; (3) mitochondrial membrane depolarization; and (4) increasing the production of cytokines. Taken together, our findings show for the first time that purified protease inhibitor from B. purpurea L. seeds is a promising candidate for the treatment of human hepatocellular carcinoma.

A thermostable trypsin inhibitor with antiproliferative activity from small pinto beans

“…However, whether the same is also true of plant trypsin inhibitors is not known. Bauhinia purpurea trypsin inhibitor BPLTI elicited apoptosis in HepG2 cells by (i) evoking DNA damage including the production of chromatin condensation and apoptotic bodies; (ii) induction of cell apoptosis/necrosis; (iii) induction of mitochondrial membrane depolarization and (iv) enhancing the production of cytokines 34 . Vicia fava trypsin inhibitor VFTI-G1 manifested specific antiproliferative activity on HepG2 hepatoma cells by triggering chromatin condensation and cell apoptosis 27 .…”

“…Hence, treatment with DTT would inhibit both types of trypsin inhibitor. On the other hand, most legume Kunitz-type trypsin inhibitors are 20-kDa [34][35][36][37][38] while legume BBIs are 16-kDa in molecular weight 27,39 . In this report, the small pinto bean trypsin inhibitor was found to be a 16-kDa protein abundant in the beans.…”

Fatores antinutricionais e digestibilidade “in vitro” de folhas de Pereskia aculeata Miller

“…Trypsin and chymotrypsin inhibitors are the most studied families and can be found in legume seeds (FANG et al, 2012), cereals (LIN et al, 2006) and legumes leaves (CHEVREUIL et al, 2011). Exposure to trypsin inhibitors results in increased synthesis and secretion of proteases (such as trypsin, chymotrypsin and elastase) and pancreatic hypertrophy and hyperplasia in animal models (FRIEDMAN et al, 2001).…”

Two legume defense proteins suppress the mobility of nasopharyngeal carcinoma cells

“…Other than the potential application in agriculture, many plant defense proteins have also been reported to demonstrate other biological functions. According to the report of Fang et al, the trypsin inhibitors isolated from Bauhinia purpurea L. seeds could induce apoptosis in hepatocellular carcinoma HepG2 cells and had anti-proliferative effects on several other cancer cell lines, like CNE-1, CNE-2 and MCF-7 cells 25 . A Bowman-Birk trypsin inhibitor from Hokkaido large black soybeans could also suppress the proliferation of MCF-7 and Hep G2 cells, but these two cell lines were not equally sensitive to the anti-proliferative effect of black soybean that the IC50 were, respectively, 35 and 140 mM for MCF-7 cells and Hep G2 cells at 72 h 26 .…”