Department of Pharmacology, Faculty of Science, Prince of Songkla University, Songkhla 90110, Thailand.
Department of Chemistry, Faculty of Science, Prince of Songkla University, Songkhla 90110, Thailand.
Biomed Pharmacother. 2017 Aug;92:732-743. doi: 10.1016/j.biopha.2017.05.130. Epub 2017 Jun 4.
Several studies have reported that active compounds isolated from Piper nigrum possess anticancer properties. However, there are no data on anticancer activity of (-)-kusunokinin and piperlonguminine. The purposes of this study were to isolate active compounds from P. nigrum and identify the molecular mechanisms underlying growth and apoptosis pathway in breast cancer cells. Two bioactive compounds, (-)-kusunokinin and piperlonguminine, were isolated from P. nigrum. Cytotoxicity and the molecular mechanism were measured by methyl thiazolyl tetrazolium (MTT) assay, flow cytometry and Western blot analysis. We found that the active compounds, which effect cancer cell lines were (-)-kusunokinin and piperlonguminine. These compounds have potent cytotoxic effects on breast cancer cells (MCF-7 and MDA-MB-468) and colorectal cells (SW-620). (-)-Kusunokinin demonstrated a cytotoxic effect on MCF-7 and MDA-MB-468 with IC values of 1.18 and 1.62μg/mL, respectively. Piperlonguminine had a cytotoxic effect on MCF-7 and MDA-MB-468 with IC values of 1.63 and 2.19μg/mL, respectively. Both compounds demonstrated lower cytotoxicity against normal breast cell lines with IC values higher than 11μg/mL. Cell cycle and apoptotic analysis using flow cytometry, showed that the (-)-kusunokinin and piperlonguminine induced cell undergoing apoptosis and drove cells towards the G2/M phase. Moreover, both compounds decreased topoisomerase II and bcl-2. The increasing of p53 levels further increased p21, bax, cytochrome c, caspase-8, -7 and -3 activities, except caspase-9. These results suggest that the (-)-kusunokinin and piperlonguminine have been shown to have potent anticancer activities through extrinsic pathway and G2/M phase arrest.
多项研究报告称，从胡椒中分离出的活性化合物具有抗癌特性。然而，目前还没有关于（-）-库苏诺因和胡椒碱的抗癌活性的数据。本研究的目的是从胡椒中分离活性化合物，并确定其在乳腺癌细胞生长和凋亡途径中的分子机制。从胡椒中分离出两种生物活性化合物（-）-库苏诺因和胡椒碱。通过噻唑蓝（MTT）测定法、流式细胞术和 Western blot 分析来测量细胞毒性和分子机制。我们发现，这些活性化合物对乳腺癌细胞（MCF-7 和 MDA-MB-468）和结直肠细胞（SW-620）均有显著的细胞毒性作用。（-）-库苏诺因对 MCF-7 和 MDA-MB-468 的细胞毒性作用的 IC 值分别为 1.18 和 1.62μg/mL。胡椒碱对 MCF-7 和 MDA-MB-468 的细胞毒性作用的 IC 值分别为 1.63 和 2.19μg/mL。两种化合物对正常乳腺细胞系的细胞毒性作用较低，IC 值均高于 11μg/mL。用流式细胞术进行细胞周期和凋亡分析表明，（-）-库苏诺因和胡椒碱诱导细胞凋亡，并使细胞进入 G2/M 期。此外，两种化合物均降低拓扑异构酶 II 和 bcl-2 的表达。p53 水平的升高进一步增加了 p21、bax、细胞色素 c、caspase-8、-7 和 -3 的活性，除 caspase-9 外。这些结果表明，（-）-库苏诺因和胡椒碱通过外源性途径和 G2/M 期阻滞显示出强大的抗癌活性。
