Critical roles of reactive oxygen species in mitochondrial permeability transition in mediating evodiamine-induced human melanoma A375-S2 cell apoptosis

Previous studies have shown that evodiamine could trigger apoptosis in human malignant melanoma A375-S2 cells within 24 h. To further investigate the biochemical basis of this activity, the roles of reactive oxygen species (ROS) and mitochondrial permeability transition (MPT) were evaluated. Exposure to evodiamine led to a rapid increase in intracellular ROS followed by an onset of mitochondrial depolarization. ROS scavenger rescued the ΔΨm dissipation and cell death induced by evodiamine, whilst MPT inhibitor blocked the second-time ROS formation as well as cell death. Expressions of key proteins in Fas- and mitochondria-mediated pathways were furthermore examined. Both pathways were activated and regulated by ROS and MPT and were converged to a final common pathway involving the activation of caspase-3. These data suggested that a phenomenon termed ROS-induced ROS release (RIRR) was involved in evodiamine-treated A375-S2 cells and greatly contributed to the apoptotic process through both extrinsic and intrinsic pathways.     

Reactive oxygen species and nitric oxide regulate mitochondria-dependent apoptosis and autophagy in evodiamine-treated human cervix carcinoma HeLa cells

The redox environment of the cell is currently thought to be extremely important to control either apoptosis or autophagy. This study reported that reactive oxygen species (ROS) and nitric oxide (NO) generations were induced by evodiamine time-dependently; while they acted in synergy to trigger mitochondria-dependent apoptosis by induction of mitochondrial membrane permeabilization (MMP) through increasing the Bax/Bcl-2 or Bcl-x_L ratio. Autophagy was also stimulated by evodiamine, as demonstrated by the positive autophagosome-specific dye monodansylcadaverine (MDC) staining as well as the expressions of autophagy-related proteins, Beclin 1 and LC3. Pre-treatment with 3-MA, the specific inhibitor for autophagy, dose-dependently decreased cell viability, indicating a survival function of autophagy. Importantly, autophagy was found to be promoted or inhibited by ROS/NO in response to the severity of oxidative stress. These findings could help shed light on the complex regulation of intracellular redox status on the balance of autophagy and apoptosis in anti-cancer therapies.     

Anti-proliferative effects of evodiamine on human prostate cancer cell lines DU145 and PC3

Prostate carcinoma is one of the most common malignant tumors and has become a more common cancer in men. Previous studies demonstrated that evodiamine (EVO) exhibited anti-tumor activities on several cancers, but its effects on androgen-independent prostate cancer are unclear. In the present study, the action mechanisms of EVO on the growth of androgen-independent prostate cancer cells (DU145 and PC3 cells) were explored. EVO dramatically inhibited the growth and elevated cytotoxicity of DU145 and PC3 cells. The flow cytometric analysis of EVO-treated cells indicated a block of G2/M phase and an elevated level of DNA fragmentation. The G2/M arrest was accompanied by elevated Cdc2 kinase activity, an increase in expression of cyclin B1 and phosphorylated Cdc2 (Thr 161), and a decrease in expression of phosphorylated Cdc2 (Tyr 15), Myt-1, and interphase Cdc25C. TUNEL examination showed that EVO-induced apoptosis was observed at 72 h. EVO elevated the activities of caspase 3, 8, and 9 in DU145 cells, while in PC3 cells only the activities of caspase 3 and 9 were elevated. EVO also triggered the processing of caspase 3 and 9 in both DU145 and PC3 cells. We demonstrate that roscovitine treatment result in the reversion of G2/M arrest in response to EVO in both DU145 and PC3. However, inhibitory effect of roscovitine on EVO-induced apoptosis could only be observed in DU145 rather than PC3. In DU145, G2/M arrest might be a signal for initiation of EVO-triggered apoptosis. Whereas EVO-triggered PC3 apoptosis might be independent of G2/M arrest. These results suggested that EVO inhibited the growth of prostate cancer cell lines, DU145 and PC3, through an accumulation at G2/M phase and an induction of apoptosis.     

Enhanced antitumor efficacy of gemcitabine by evodiamine on pancreatic cancer via regulating PI3K/Akt pathway

Evodiamine has therapeutic potential against cancers. This study was designed to investigate whether combination therapy with gemcitabine and evodiamine enhanced antitumor efficacy in pancreatic cancer. In vitro application of the combination therapy triggered significantly higher frequency of pancreatic cancer cells apoptosis, inhibited the activities of PI3K, Akt, PKA, mTOR and PTEN, and decreased the activation of NF-κB and expression of NF-κB-regulated products. In vivo application of the combination therapy induced significant enhancement of tumor cell apoptosis, reductions in tumor volume, and inhibited activation of mTOR and PTEN. In conclusion, evodiamine can augment the therapeutic effect of gemcitabine in pancreatic cancer through direct or indirect negative regulation of the PI3K/Akt pathway.     

Protein tyrosine kinase pathway-derived ROS/NO productions contribute to G2/M cell cycle arrest in evodiamine-treated human cervix carcinoma HeLa cells

Abstract

A previous study indicated that reactive oxygen species (ROS) and nitric oxide (NO) played pivotal roles in mediating cytotoxicity of evodiamine in human cervix carcinoma HeLa cells. This study suggested that G2/M cell cycle arrest was triggered by ROS/NO productions with regulations of p53, p21, cell division cycle 25C (Cdc25C), Cdc2 and cyclin B1, which were able to be prevented by protein tyrosine kinase (PTK) activity inhibitor genistein or JNK inhibitor SP600125. The decreased JNK phosphorylation by addition of Ras or Raf inhibitor, as well as the increased cell viability by addition of insulin-like growth factor-1 receptor (IGF-1R), Ras, Raf or c-Jun N-terminal kinase (JNK) inhibitor, further demonstrated that the Ras-Raf-JNK pathway was responsible for this PTK-mediated signalling. These observations provide a distinct look at PTK pathway for its suppressive effect on G2/M transition by inductions of ROS/NO generations.     

Induction of Apoptosis and Effect on the FAK/AKT/mTOR Signal Pathway by Evodiamine in Gastric Cancer Cells

Evodiamine isolated from Evodia rutaecarpa has been known to have anti-tumor activity against various cancer cell types. Although there have been reports showing the inhibitory effect of evodiamine on cell survival of gastric cancer cell, it is not clearly explained how evodiamine affects the expression and modification of proteins associated with apoptosis and upstream signal pathways. We confirmed the cytotoxic activity of evodiamine against AGS and MKN45 cells by a WST assay, cell morphological change, and clonogenic assay. The apoptotic cells were evaluated by Annexin V/PI analysis and Western blot and the expressions of apoptosis-related molecules were confirmed by Western blot. Evodiamine promoted apoptosis of AGS gastric cancer cells through both intrinsic and extrinsic signal pathways in a time- and dose-dependent manner. Evodiamine attenuated the expression of anti-apoptotic proteins, including Bcl-2, XIAP, and survivin, and elevated that of the pro-apoptotic protein Bax. Evodiamine also suppressed the FAK/AKT/mTOR signal pathway. Based on these results, we expect that the results from this study will further elucidate our understanding of evodiamine as an anti-cancer drug.     

吴茱萸碱对黑色素瘤细胞的耐药逆转作用

黑色素瘤是目前恶性程度最高的肿瘤之一。临床上,常采用维罗非尼（PLX4032）作为晚期患者的治疗药物,但患者很快就出现了耐药。因此,如何克服耐药、提高患者生存率成为急需解决的问题。本文选用中药吴茱萸碱（EVO）与黑色素瘤A375细胞、对PLX4032耐药的A375细胞（A375/R）进行相关研究。采用CCK-8法检测发现,用EVO的细胞非毒性浓度0.5 μmol/L处理A375/R,PLX4032对A375/R细胞的半数抑制浓度（IC50）降低,逆转倍数为3.85。显示EVO能够增强黑色素瘤A375/R细胞对PLX4032的敏感性。后续实验分为对照组、EVO组、PLX组、PLX + EVO组。流式细胞仪检测结果显示,EVO组细胞凋亡率为5.88%,PLX组细胞凋亡率为17.88%,PLX + EVO组细胞凋亡率为30.28%。细胞集落结果证明,PLX4032联合EVO能够抑制A375/R细胞的克隆形成。免疫印迹法结果证明,联合用药能够上调促凋亡蛋白质Bax、胱天蛋白酶3的表达量,下调p-Akt、p-NF-κB-p65及抗凋亡蛋白Bcl-2的蛋白质水平。以上结果均表明,EVO能够有效逆转黑色素瘤A375/R细胞耐药,并且诱导细胞凋亡,抑制细胞增殖。     

Evodiamine inhibits the proliferation of leukemia cell line K562 by regulating peroxisome proliferators-activated receptor gamma (PPARγ) pathway

Evodiamine, a quinolone alkaloid, is one of the major bioactive compounds of Evodia rutaecarpa Bentham (Rutaceae). It exhibits excellent biological activities, especially the anticancer activity. This study aims to investigate the effect of evodiamine on the proliferation of leukemia cell line K562 and to explore the underlying mechanism. The effect of evodiamine on K562 cells proliferation was analyzed by trypan blue dye exclusion assay and MTT assay. The expression levels of peroxisome proliferators-activated receptor gamma (PPARγ), cyclin D1, and p21 were detected by western blot assay. The results demonstrated that evodiamine inhibited the proliferation and decreased the viability of K562 cells in a dose- and time-dependent manner. 2-Chloro-5-nitro-N-phenylbenzamide (GW9662) and/or PPARγ-siRNA pretreatment alleviated the cell growth suppression triggered by evodiamine. Meanwhile, evodiamine intervention elevated the expression of PPARγ in K562 cells, while pretreatment with GW9662 attenuated the enhanced upregulation of PPARγ expression induced by evodiamine. In addition, GW9662 and PPARγ-siRNA pretreatment also significantly attenuated the downregulation of the cell cycle control protein cyclin D1 and the upregulation of cyclin-dependent kinase inhibitor p21 induced by evodiamine. In conclusion, PPARγ signaling pathway may involve in the proliferation inhibition of evodiamine on K562 cells via inhibiting cylcin D1 and stimulating of p21.     

Evodiamine and rutaecarpine inhibit migration by LIGHT via suppression of NADPH oxidase activation

LIGHT acted as a new player in the atherogenesis. The dried, unripe fruit of Evodia Fructus (EF) has long been used as a traditional Chinese herbal medicine, and is currently widely used for the treatment of headache, abdominal pain, vomiting, colds and reduced blood circulation. Evodiamine and rutaecarpine are active components of EF. In this study, we investigated the inhibitory effect of evodiamine and rutaecarpine on LIGHT‐induced migration in human monocytes. Evodiamine and rutaecarpine decreased the LIGHT‐induced production of ROS, IL‐8, monocyte chemoattractant protein‐1 (MCP‐1), TNF‐α, and IL‐6, as well as the expression of chemokine receptor (CCR) 1, CCR2 and ICAM‐1 and the phosphorylation of the ERK 1/2 and p38 MAPK. Furthermore, NADPH oxidase assembly inhibitor, AEBSF, blocked LIGHT‐induced migration and activation of CCR1, CCR2, ICAM‐1, and MAPK such as ERK and p38 in a manner similar to evodiamine and rutaecarpine. These findings indicate that the inhibitory effects of evodiamine and rutaecarpine on LIGHT‐induced migration and the activation of CCR1, CCR2, ICAM‐1, ERK, and p38 MAPK occurs via decreased ROS production and NADPH oxidase activation. Taken together, these results indicate that evodiamine and rutaecarpine have the potential for use as an anti‐atherosclerosis agent. J. Cell. Biochem. 107: 123–133, 2009. © 2009 Wiley‐Liss, Inc.