Park See-Hyoung, Phuc Nguyen Minh, Lee Jongsung, Wu Zhexue, Kim Jieun, Kim Hyunkyoung, Kim Nam Doo, Lee Taeho, Song Kyung-Sik, Liu Kwang-Hyeon
Department of Bio and Chemical Engineering, Hongik University, Sejong 30016, Republic of Korea.
BK21 Plus KNU Multi-Omics based Creative Drug Research Team, College of Pharmacy and Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu 41566, Republic of Korea.
Phytomedicine. 2017 Jan 15;24:134-140. doi: 10.1016/j.phymed.2016.12.001. Epub 2016 Dec 2.
Acetylshikonin is one of the biologically active compounds derived from the root of Lithospermum erythrorhizon, a medicinal plant with anti-cancer and anti-inflammation activity. Although there have been a few previous reports demonstrating that acetylshikonin exerts anti-cancer activity in vitro and in vivo, it is still not clear what is the exact molecular target protein of acetylshikonin in cancer cells.
The purpose of this study is to evaluate the inhibitory effect of acetylshikonin against CYP2J2 enzyme which is predominantly expressed in human tumor tissues and carcinoma cell lines.
The inhibitory effect of acetylshikonin on the activities of CYP2J2-mediated metabolism were investigated using human liver microsomes (HLMs), and its cytotoxicity against human hepatoma HepG2 cells was also evaluated.
Astemizole, a representative CYP2J2 probe substrate, was incubated in HLMs in the presence or absence of acetylshikonin. After incubation, the samples were analyzed by liquid chromatography and triple quadrupole mass spectrometry. The anti-cancer activity of acetylshikonin was evaluated on human hepatocellular carcinoma HepG2 cells. WST-1, cell counting, and colony formation assays were further adopted for the estimation of the growth rate of HepG2 cells treated with acetylshikonin.
Acetylshikonin inhibited CYP2J2-mediated astemizole O-demethylation activity (K = 2.1µM) in a noncompetitive manner. The noncompetitive inhibitory effect of acetylshikonin on CYP2J2 enzyme was also demonstrated using this 3D structure, which showed different binding location of astemizole and acetylshikonin in CYP2J2 model. It showed cytotoxic effects against human hepatoma HepG2 cells (IC = 2μM). In addition, acetylshikonin treatment inhibited growth of human hepatocellular carcinoma HepG2 cells leading to apoptosis accompanied with p53, bax, and caspase3 activation as well as bcl2 down-regulation.
Taken together, our present study elucidates acetylshikonin displays the inhibitory effects against CYP2J2 in HLMs and anti-cancer activity in human hepatocellular carcinoma HepG2 cells.
乙酰紫草素是从药用植物紫草的根中提取的具有生物活性的化合物之一，紫草具有抗癌和抗炎活性。尽管之前有一些报道表明乙酰紫草素在体外和体内均具有抗癌活性，但尚不清楚其在癌细胞中的具体分子靶蛋白是什么。
本研究旨在评估乙酰紫草素对主要在人肿瘤组织和癌细胞系中表达的CYP2J2酶的抑制作用。
使用人肝微粒体（HLM）研究乙酰紫草素对CYP2J2介导的代谢活性的抑制作用，并评估其对人肝癌HepG2细胞的细胞毒性。
将代表性的CYP2J2探针底物阿司咪唑在有或没有乙酰紫草素存在的情况下于HLM中孵育。孵育后，通过液相色谱和三重四极杆质谱对样品进行分析。在人肝癌HepG2细胞上评估乙酰紫草素的抗癌活性。进一步采用WST-1、细胞计数和集落形成试验来估计用乙酰紫草素处理的HepG2细胞的生长速率。
乙酰紫草素以非竞争性方式抑制CYP2J2介导的阿司咪唑O-去甲基化活性（K = 2.1µM）。使用该三维结构也证明了乙酰紫草素对CYP2J2酶的非竞争性抑制作用，该结构显示了阿司咪唑和乙酰紫草素在CYP2J2模型中的不同结合位置。它对人肝癌HepG2细胞显示出细胞毒性作用（IC = 2μM）。此外，乙酰紫草素处理抑制了人肝癌HepG2细胞的生长，导致细胞凋亡，并伴有p53、bax和caspase3激活以及bcl2下调。
综上所述，我们目前的研究阐明了乙酰紫草素对HLM中的CYP2J2具有抑制作用，并对人肝癌HepG2细胞具有抗癌活性。
