Deoxyelephantopin Research Articles

Deoxyelephantopin induces apoptosis and cell cycle arrest in GL261 glioblastoma cells.

Glioblastoma multiforme (GBM) is a highly malignant central nervous system tumor with a poor prognosis. Developing new therapeutic drugs is crucial. This study evaluates deoxyelephantopin (DET), a major component of *Elephantopus scaber* L., for its potential anti-GBM effects. The effects of DET on GBM cell lines were investigated using the MTT assay and Annexin-V kit to assess cell death and apoptosis. Western blot analysis examined apoptosis and cell cycle-related proteins. ELISA kits measured VEGF and TGF-β levels. In vivo, NOD SCID mice were injected with GL-261 cells and treated with DET to evaluate tumor growth and survival. DET inhibited GBM cell growth in a time- and dose-dependent manner. MTT and Annexin-V assays confirmed cell death and apoptosis. Western blot analysis showed DET downregulated Bcl-2 and increased caspase-3, Bax, and cytochrome c levels. ELISA results indicated that DET suppressed VEGF and TGF-β expression. DET treatment also decreased phosphorylation of AKT and STAT-3, CDK4, cyclin D2, MMP2, and MMP9 levels. In vivo, DET significantly inhibited tumor growth and improved survival rates in mice. DET exhibits significant in vitro and in vivo anticancer effects, making it a promising candidate for further research and potential clinical application against GBM.

Deoxyelephantopin—a novel PPARγ agonist regresses pressure overload-induced cardiac fibrosis via IL-6/STAT-3 pathway in crosstalk with PKCδ

Pathological cardiac hypertrophy is associated with ventricular fibrosis leading to heart failure. The use of thiazolidinediones as Peroxisome Proliferator-Activated Receptor-gamma (PPARγ)-modulating anti-hypertrophic therapeutics has been restricted due to major side-effects. The present study aims to evaluate the anti-fibrotic potential of a novel PPARγ agonist, deoxyelephantopin (DEP) in cardiac hypertrophy. AngiotensinII treatment in vitro and renal artery ligation in vivo were performed to mimic pressure overload-induced cardiac hypertrophy. Myocardial fibrosis was evaluated by Masson's trichrome staining and hydroxyproline assay. Our results showed that DEP treatment significantly improves the echocardiographic parameters by ameliorating ventricular fibrosis without any bystander damage to other major organs. Following molecular docking, all-atomistic molecular dynamics simulation, reverse transcription-polymerase chain reaction and immunoblot analyses, we established DEP as a PPARγ agonist stably interacting with the ligand-binding domain of PPARγ. DEP specifically downregulated the Signal Transducer and Activator of Transcription (STAT)-3-mediated collagen gene expression in a PPARγ-dependent manner, as confirmed by PPARγ silencing and site-directed mutagenesis of DEP-interacting PPARγ residues. Although DEP impaired STAT-3 activation, it did not have any effect on the upstream Interleukin (IL)-6 level implying possible crosstalk of the IL-6/STAT-3 axis with other signaling mediators. Mechanistically, DEP increased the binding of PPARγ with Protein Kinase C-delta (PKCδ) which impeded the membrane translocation and activation of PKCδ, downregulating STAT-3 phosphorylation and resultant fibrosis. This study, therefore, for the first time demonstrates DEP as a novel cardioprotective PPARγ agonist. The therapeutic potential of DEP as an anti-fibrotic remedy can be exploited against hypertrophic heart failure in the future.

Deoxyelephantopin, a germacrane-type sesquiterpene lactone from Elephantopus scaber, induces mitochondrial apoptosis of hepatocarcinoma cells by targeting Hsp90α in vitro and in vivo.

Hepatocellular carcinoma has been known as the most frequent subtype of liver cancer with a high rate of spread, metastases, and recurrence, also dismal treatment effects. However, effective therapies for HCC are still required. Nowadays, natural products have been known as a valuable source for drug discovery. In this research, 44 sesquiterpene lactones isolated from the Elephantopus scaber Linn. (Asteraceae) were tested by MTT assay for the antitumor activities. Deoxyelephantopin (DET) was found to exert significant cytotoxicity on HepG2 and Hep3B cells. Moreover, we found that DET treatment markedly reduced the growth of HCC cells in a concentration-dependent manner, which was better than sorafenib. Furthermore, DET induced mitochondrial dysfunction, oxidative stress, and cellular apoptosis. Additionally, we found that DET and sorafenib synergistically induced apoptosis and mitochondrial dysfunction in HCC cells. DET combined with sorafenib was also efficacious in tumor xenograft model. Molecular docking experiments revealed that DET had a potentially high binding affinity with Hsp90α. Moreover, Drug Affinity Responsive Target Stability assay suggested that DET could directly target Hsp90α. Additionally, the expression of Hsp90α was both decreased in vitro and in vivo. Altogether, this study revealed that DET might be a promising agent for HCC therapy by targeting Hsp90α.

MicroRNA-Mediated Mitochondrial Dysfunction Is Involved in the Anti-triple-Negative Breast Cancer Cell Activity of Phytosesquiterpene Lactones.

Aims: Emerging evidence suggests that modulating redox homeostasis through targeting mitochondrial functions may be a useful strategy for suppressing triple-negative breast cancer (TNBC) activities. However, whether there are specific microRNAs (miRNAs) involved in regulating oxidative stress-associated mitochondrial functions that can act as therapeutic targets to suppress TNBC activities remains unclear. Here, we aimed to identify the role of redox-associated miRNAs in TNBC and investigated their potential as therapeutic targets. Results: We identified oxidative stress-responsive differentially expressed miRNAs (DEMs) regulated by phytosesquiterpene lactone deoxyelephantopin (DET) and its novel derivative DETD-35, which are known to inhibit TNBC growth and metastasis in vitro and in vivo, using comparative miRNA microarray analysis and reactive oxygen species (ROS) scavenging approaches. Mitochondrial dysfunction was identified as a major biological function regulated by a few specific DEMs. In particular, miR-4284 was identified to play a role in DET- and DETD-35-mediated ROS production, mitochondrial basal proton leak, and antiproliferation activity in TNBC cells. Moreover, DET- and DETD-35-induced mitochondrial DNA damage was observed in TNBC cells and xenograft tumors. miR-4284 was also identified to play a role in oxidative DNA damage in TNBC tumors. Innovation: We identified a novel role for miR-4284 in regulating mitochondrial basal proton leak in TNBC cells, and highlighted its significance in TNBC tumor oxidative DNA damage, and its direct correlation with TNBC patient survival. Conclusion: We used DET and DETD-35 as proof of concept to demonstrate that activities of anticancer agents can involve regulation of multiple miRNAs playing different roles in cancer progression. Antioxid. Redox Signal. 38, 198-214.

Deoxyelephantopin Suppresses Pancreatic Cancer Progression In Vitro and In Vivo by Targeting linc00511/miR-370-5p/p21 Promoter Axis.

Objectives Deoxyelephantopin (DET) is a kind of natural active ingredient extracted from the Chinese herbal medicine Elephantopus scaber L. Many studies have revealed the potential antitumor effect on multiple malignancies. However, the detailed mechanism of its antitumor effect in pancreatic cancer remains unclear. Recently, studies have confirmed that noncoding RNA (ncRNA) plays an important regulatory role in malignancies. This research was performed to explore the relationship between ncRNA and DET-induced tumor inhibition in pancreatic cancer. Methods Microarray profiling was applied to identify the candidate ncRNAs associated with DET-induced tumor inhibition. Quantitative real-time PCR was used to evaluate the expression of linc00511 in pancreatic cancer cells and tissues. The influence of DET on the cell proliferation, migration, and invasion was assessed by CCK-8, colony formation, wound healing, and Transwell assays. The relationship between lncRNAs, miRNAs, and p21 promoter region was analyzed by bioinformatics and verified by luciferase reporter gene and western blotting. The effect of linc00511 on nuclear translocation of miR-370-5p was explored by cytoplasmic and nuclear RNA purification. Moreover, the effect of DET on tumor growth and metastasis, and the prophylactic effect were investigated by establishing subcutaneous and lung metastatic tumor models. Results Microarray assay indicated linc00511 was a potential target gene. The antitumor effect of DET in pancreatic cancer depended on downregulating linc00511 expression, and linc00511 might be an oncogene in pancreatic cancer. Silencing linc00511 enhanced the antitumor function of DET; conversely, linc00511 overexpression antagonized the DET cytotoxic effect. Additionally, miR-370-5p could bind to p21 promoter to exert the RNA activation and then promote p21 expression. P21 was a downstream gene of linc00511 and associated with pancreatic cancer progression. Linc00511 regulated p21 expression by blocking miR-370-5p nuclear translocation. Conclusions To sum up, the present finding confirmed that DET suppressed the malignant biological behavior of pancreatic cancer via linc00511/miR-370-5p/p21 promoter axis.

Deoxyelephantopin Induces Apoptosis and Enhances Chemosensitivity of Colon Cancer via miR-205/Bcl2 Axis.

Colon cancer (CC) is one of the major causes of cancer death in humans. Despite recent advances in the management of CC, the prognosis is still poor and a new strategy for effective therapy is imperative. Deoxyelephantopin (DET), extracted from an important medicinal plant, Elephantopus scaber L., has been reported to exhibit excellent anti-inflammatory and -cancer activities, while the detailed anti-cancer mechanism remains unclear. Herein, we found that DET showed a significant CC inhibiting effect in vitro and in vivo without obvious organ toxicity. Mechanistically, DET inhibited CC cells and tumor growth by inducing G2/M phase arrest and subsequent apoptosis. DET-mediated cell cycle arrest was caused by severe DNA damage, and DET decreased the Bcl2 expression level in a dose-dependent manner to promote CC cell apoptosis, whereas restoring Bcl2 expression reduced apoptosis to a certain extent. Moreover, we identified a microRNA complementary to the 3′-UTR of Bcl2, miR-205, that responded to the DET treatment. An inhibitor of miR-205 could recover Bcl2 expression and promoted the survival of CC cells upon DET treatment. To further examine the potential value of the drug, we evaluated the combinative effects of DET and 5-Fluorouracil (5FU) through Jin’s formula and revealed that DET acted synergistically with 5FU, resulting in enhancing the chemotherapeutic sensitivity of CC to 5FU. Our results consolidate DET as a potent drug for the treatment of CC when it is used alone or combined with 5FU, and elucidate the importance of the miR-205-Bcl2 axis in DET treatment.

Targeting thioredoxin reductase by deoxyelephantopin from Elephantopus scaber triggers cancer cell apoptosis

Elevated expression of thioredoxin reductase (TrxR) is associated with the tumorigenesis and resistance to cancer chemoradiotherapy, highlighting the potential of TrxR inhibitors as anticancer drugs. Deoxyelephantopin (DET) is the major active ingredient of Elephantopus scaber and reveals potent anticancer activity. However, the potential mechanism of action and the cellular target of DET are still unknown. Here, we found that DET primarily targets the Sec residue of TrxR and irreversibly prohibits enzyme activity. Suppression of TrxR by DET leads to accumulation of reactive oxygen species and dysregulation in intracellular redox balance, eventually inducing cancer cell apoptosis mediated by oxidative stress. Noticeably, down-regulation of TrxR1 by shRNA increases cell sensitivity to DET. Collectively, targeting of TrxR1 by DET uncovers a novel mechanism of action in DET and deepens the understanding of developing DET as a potential chemotherapeutic agent for treating cancers.

Sesquiterpene Lactone Deoxyelephantopin Isolated from Elephantopus scaber and Its Derivative DETD-35 Suppress BRAFV600E Mutant Melanoma Lung Metastasis in Mice.

Melanoma is a highly metastatic disease with an increasing rate of incidence worldwide. It is treatment refractory and has poor clinical prognosis; therefore, the development of new therapeutic agents for metastatic melanoma are urgently required. In this study, we created a lung-seeking A375LM5IF4g/Luc BRAFV600E mutant melanoma cell clone and investigated the bioefficacy of a plant sesquiterpene lactone deoxyelephantopin (DET) and its novel semi-synthetic derivative, DETD-35, in suppressing metastatic A375LM5IF4g/Luc melanoma growth in vitro and in a xenograft mouse model. DET and DETD-35 treatment inhibited A375LM5IF4g/Luc cell proliferation, and induced G2/M cell-cycle arrest and apoptosis. Furthermore, A375LM5IF4g/Luc exhibited clonogenic, metastatic and invasive abilities, and several A375LM5IF4g/Luc metastasis markers, N-cadherin, MMP2, vimentin and integrin α4 were significantly suppressed by treatment with either compound. Interestingly, DET- and DETD-35-induced Reactive Oxygen Species (ROS) generation and glutathione (GSH) depletion were found to be upstream events important for the in vitro activities, because exogenous GSH supplementation blunted DET and DETD-35 effects on A375LM5IF4g/Luc cells. DET and DETD-35 also induced mitochondrial DNA mutation, superoxide production, mitochondrial bioenergetics dysfunction, and mitochondrial protein deregulation. Most importantly, DET and DETD-35 inhibited lung metastasis of A375LM5IF4g/Luc in NOD/SCID mice through inhibiting pulmonary vascular permeability and melanoma cell (Mel-A+) proliferation, angiogenesis (VEGF+, CD31+) and EMT (N-cadherin) in the tumor microenvironment in the lungs. These findings indicate that DET and DETD-35 may be useful in the intervention of lung metastatic BRAFV600E mutant melanoma.

Abstract PR05: Unique lipid metabolite profiling in BRAFV600E inhibitor drug-resistant melanoma and their potential as drug target

Abstract Melanoma is the most life-threatening skin cancer in the world. Advanced melanoma is highly metastatic, commonly develops drug resistance, and causes low survival rate in patients. PLX4032 (vemurafenib), a BRAFV600E inhibitor, is used to treat patients with late-stage melanoma. It showed initial good clinical responses but relapsed due to acquired drug resistance in tumors. The mechanism of PLX4032-induced resistance in melanoma is not well characterized; in particular, whether PLX4032-induced drug resistance in BRAF mutant melanoma would alter lipid metabolism in cancer is not clear. Understanding the status and role of lipid mediators (oxylipins) in melanoma pathology may be crucial for developing effective approach to overcome drug resistance. Our laboratory has demonstrated that plant sesquiterpene lactone deoxyelephantopin (DET) and its novel derivative DETD-35 effectively suppressed human A375 BRAFV600E melanoma with acquired drug resistance to PLX4032 in vitro and in xenograft mice. In this study we aimed to identify potential biomarkers associated with the resistant melanoma cells (A375-R) in the context of bioactive lipid mediators and to investigate whether DETD-35/DET effects against drug-resistant melanoma are through regulating their dynamics and contents. MS-based metabolomics was used to comprehensively analyze the oxylipin profiles in A375 and A375-R cells, mouse A375/A375-R tumor tissues, and respective sera with vehicle, drug, or compound treatment. We observed that PLX4032-resistant A375R melanoma cells or tumors produce significant and higher amounts of CYP450 enzyme-derived oxylipins than the parental A375, which were decreased after DETD-35 or DET treatment. This study proposes a role of CYP450-derived oxylipins in PLX4032-resistant melanoma cells and its potential to be a drug target. This abstract is also being presented as Poster B03. Citation Format: Meng-Ting Chang, Jia-Hua Feng, Kyoko Nakagawa-Goto, Kuo-Hsiung Lee, Lie-Fen Shyur. Unique lipid metabolite profiling in BRAFV600E inhibitor drug-resistant melanoma and their potential as drug target [abstract]. In: Proceedings of the AACR Special Conference on Melanoma: From Biology to Target; 2019 Jan 15-18; Houston, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(19 Suppl):Abstract nr PR05.

Deoxyelephantopin, a novel naturally occurring phytochemical impairs growth, induces G2/M arrest, ROS-mediated apoptosis and modulates lncRNA expression against uterine leiomyoma

Deoxyelephantopin (DOE), a phytochemical, extracted and purified from Elephantopus scaber, has been shown to exhibit antitumor activities. Objective of the present study was to investigate anti-tumor and apoptosis-inducing properties of DOE against uterine leiomyoma (UL) and to explore their molecular mechanisms. Primary cell cultures from fresh UL tissue were established and maintained up to 12 passages. The cells exhibited continuous proliferation with 24 -h doubling time until 12 passages and was then subjected to molecular characterization. The growth inhibitory effect of DOE on UL cells was confirmed by colony formation, cellular senescence, AO/PI and DAPI staining. Fluorescent-activated cell sorting (FACS) assay for apoptosis and cell cycle arrest analysis revealed that DOE significantly (p < 0.05) inhibited the UL cell proliferation via cell cycle arrest at G2/M phase and induced apoptosis via ROS production by lowering mitochondrial membrane potential. Subsequently, the DOE induced ROS was markedly attenuated by co-treatment of N-Acetyl-Cysteine (NAC). Our quantitative RT-PCR and western blot results showed up-regulation of Bax, Caspase-3 and down-regulation of Bcl2, P53, αSMA, COL4A2, VEGF, PCNA, Cyclin B1 and oncogenic lncRNAs (H19, HOTAIR, BANCR and ROR) in DOE treated UL cells which further strengthen our findings. In conclusion, DOE inhibits growth of UL cells via cell cycle arrest at G2/M phase, induces ROS-dependent caspase-3-mediated mitochondrial intrinsic apoptotic pathway and down-regulation of oncogenic lncRNA in UL cells. Our findings suggest that DOE deserves for further systematic investigation in the uterine leiomyoma animal model as a novel apoptosis inducer for potential applications in the prevention or treatment of uterine leiomyoma.

Deoxyelephantopin induces apoptosis via oxidative stress and enhances gemcitabine sensitivity in vitro and in vivo through targeting the NF-κB signaling pathway in pancreatic cancer.

Pancreatic cancer is a highly invasive malignant tumor of the digestive system with an unfavorable prognosis worldwide. This trait is thought to be largely attributed to chemoresistance. Chemotherapy is the only hope for patients with advanced pancreatic cancer. Therefore, seeking new effective chemotherapy drugs has become an urgent need. The purpose of our study was to explore whether deoxyelephantopin (DET), a sesquiterpene lactone, has a potential antitumor effect in pancreatic cancer. Additionally, the antitumor effects of DET alone or in combination with gemcitabine (GEM) and the potential mechanism of this combination were revealed. In vitro experiments showed that DET suppressed the proliferation, invasion and metastasis of pancreatic cancer cells, induced cell apoptosis via oxidative stress, and enhanced GEM sensitivity by inhibiting the NF-κB signaling pathway. Beyond that, in vivo experiments showed that DET not only inhibited pancreatic tumor growth and metastasis but also amplified the antitumor capacity of GEM, which was related to the downregulation of NF-κB and its downstream gene products. In summary, it is possible that DET could be developed as a single agent or combined with conventional chemotherapy drugs to improve the treatment of pancreatic cancer.

Deoxyelephantopin decreases the release of inflammatory cytokines in macrophage associated with attenuation of aerobic glycolysis via modulation of PKM2

Growing evidence suggests that activated immune cells undergo metabolic reprogramming in the regulation of the innate inflammatory response. Remarkably, macrophages activated by lipopolysaccharide (LPS) induce a switch from oxidative phosphorylation to aerobic glycolysis, and consequently results in release of proinflammatory cytokines. Pyruvate Kinase M2 (PKM2) plays a vital role in the process of macrophage activation, promoting the inflammatory response in sepsis and septic shock. Deoxyelephantopin (DET), a naturally occurring sesquiterpene lactone from Elephantopus scaber, has been shown to counteracts inflammation during fulminant hepatitis progression, but the underlying mechanism remains unclear. Here, we studied the function of the DET on macrophage activation and investigated the anti-inflammatory effects of DET associated with interfering with glycolysis in macrophage. Our results first demonstrated that DET attenuates LPS-induced interleukin-1β (IL-1β) and high-mobility group box 1 (HMGB1) release in vitro and in vivo and protected mice against lethal endotoxemia. Furthermore, DET decreased the expression of pyruvate dehydrogenase kinase 1 (PDK1), glucose transporter 1(GLUT1), lactate dehydrogenase A (LDHA), and reduced lactate production dose-dependently in macrophages. Moreover, we further revealed that DET attenuates aerobic glycolysis in macrophages associated with regulating the nuclear localization of PKM2. Our results provided a novel mechanism for DET suppression of macrophages activation implicated in anti-inflammatory therapy.

Isodeoxyelephantopin, a Sesquiterpene Lactone Induces ROS Generation, Suppresses NF-\u03baB Activation, Modulates LncRNA Expression and Exhibit Activities Against Breast Cancer

The sesquiterpene lactones, Isodeoxyelephantopin (IDET) and Deoxyelephantopin (DET) are known to exhibit activities against some cancer types. The activities of these lactones against breast cancer and the molecular bases is not known. We examined the efficacy of lactones in breast cancer preclinical model. Although both lactones exhibited drug like properties, IDET was relatively effective in comparison to DET. IDET suppressed the proliferation of both invasive and non-invasive breast cancer cell lines. IDET also suppressed the colony formation and migration of breast cancer cells. The assays for Acridine Orange (AO)/Propidium Iodide (PI) staining, cell cycle distribution, phosphatidylserine externalization and DNA laddering suggested the apoptosis inducing potential of IDET. The treatment with IDET also induced an accumulation of cells in the sub-G1 and G2/M phases. The exposure of breast cancer cells to the lactone was associated with a depolarization in mitochondrial membrane potential, and cleavage of caspase and PARP. The lactone induced reactive oxygen species (ROS) generation in breast cancer cells. Further, the use of N-acetyl cysteine (NAC) suppressed IDET induced ROS generation and apoptosis. The NF-κB-p65 nuclear translocation induced by okadaic acid (OA) was suppressed by the sesquiterpene. IDET also suppressed the expression of NF-κB regulated tumorigenic proteins, and induced the expression of proapoptotic gene (Bax) in cancer cells. While the expression of oncogenic lncRNAs was suppressed, the tumor suppressor lncRNAs were induced by the sesquiterpene. Collectively, the modulation of multiple cell signaling molecules by IDET may contribute to its activities in breast cancer cells.

Deoxyelephantopin suppresses hepatic stellate cells activation associated with inhibition of aerobic glycolysis via hedgehog pathway

Accumulating evidence suggests that hepatic stellate cells (HSCs) adopt aerobic glycolysis during activation. Hedgehog (Hh) pathway plays a vital role in the process of HSCs activation by regulating metabolism, and activation of the Hh pathway promotes transdifferentiation of HSCs into myofibroblasts. Deoxyelephantopin (DET), a naturally occurring sesquiterpene lactone from Elephantopus scaber, has been shown to exert hepatoprotective as well as anticancer effects. However, the effect of DET on hepatic fibrosis and glycolysis in HSCs have never been elucidated. Here, we studied the function of the DET on HSCs activation and investigated the anti-fibrogenic effects of DET was associated with interfering with glycolysis in HSCs. Our results first demonstrated that DET reduced the expression of a-smooth muscle actin (a-SMA) and a1(I)procollagen at both mRNA and protein levels, and restore lipogenesis in HSCs. Furthermore, DET decreased the expression of hexokinase (HK), phosphofructokinase-2 (PFK2), Glucose transporter 4 (Glut4), and reduced lactate production dose-dependently in HSCs. Moreover, we further revealed that DET reduced fibrotic gene expression, restored lipid accumulation in HSCs. However, the Hh pathway agonist SAG could reverse the above effect of DET. Together, these results indicate DET inhibits aerobic glycolysis in HSCs associated with inhibition of Hh pathway. Our results provided a novel mechanism for DET suppression of HSC activation implicated in antifibrotic therapy.

In vitro and in vivo antitumor activity of deoxyelephantopin from a potential medicinal plant Elephantopus scaber against Ehrlich ascites carcinoma

Elephantopus scaber Linn. is a perennial medicinal herb widely used in Asian traditional medicine for the treatment of different kinds of neoplasm. The aim of the present study was to appraise the in vitro and in vivo antitumor activity of deoxyelephantopin (DOE) - the active principle isolated from E. scaber against murine Ehrlich ascites carcinoma (EAC). Intraperitoneal administration of DOE (25 mg/kg) reduced the ascites tumor volume to a better extend than the treatments with same concentrations of 5-Flourouracil (5-FU) in EAC ascites tumor model and increased the life span of treated mice with respect to control mice (p ˂ 0.001). Moreover, treatment with 25 mg/kg DOE reduced the tumor volume and tumor burden in EAC solid tumor model and showed the best overall survival responses (Log-Rank p value < 0.001). DOE exhibited impressive cytotoxicity against EAC cells in vitro. Morphological analysis of DOE-treated EAC cells showed membrane blebbing, chromatin condensation and nuclear fragmentation-signs of apoptotic cell death. Assessment for DNA laddering in DOE-treated EAC cells confirmed that DOE caused EAC cell death by apoptosis. The present study showed that even lower doses of DOE has better in vivo antitumor activity, than the widely used chemotherapeutic agent- 5-FU. Thus, it is obvious that DOE shall be developed as a useful chemotherapeutic drug for cancer treatment in near future.

Phyto-sesquiterpene lactone deoxyelephantopin and cisplatin synergistically suppress lung metastasis of B16 melanoma in mice with reduced nephrotoxicity

BackgroundCisplatin (CP) is a chemotherapeutic drug for treating melanoma that also causes adverse side effects in cancer patients. PurposeThis study investigated the bioefficacy of a phytoagent deoxyelephantopin (DET) in inhibiting B16 melanoma cell activity, its synergism with CP against metastatic melanoma, and its capability to attenuate CP side effects in animals. MethodsDET and CP bioactivities were assessed by MTT assay, isobologram analysis, time-lapse microscopy, migration and invasion assays, flow cytometry and western blotting. In vivo bioluminescence imaging was used to detect lung metastasis of B16 cells carrying COX-2 reporter gene in syngeneic mice. H&E staining and immunohistochemistry were used to evaluate the compound/drug efficacy and CP side effects. Nephrotoxicity caused by CP treatment in mice was evaluated by UPLC/ESI-QTOF MS − based metabolomics and haematometry. ResultDET, alone or in combination with cisplatin, inhibited B16 cell proliferation, migration, and invasion, and induced cell-cycle arrested at the G2/M phase and de-regulated cell-cycle mediators in cancer cells. In a murine B16COX-Luc metastatic allograft model, CP2 (2 mg/kg) treatment inhibited B16 lung metastasis accompanied by severe body weight loss, renal damage and inflammation, and haematological toxicity. DET10 and CP cotreatment (DET10 + CP1) or sequential treatment (CP2→DET10) significantly inhibited formation of pulmonary melanoma foci and reduced renal damage. DET pretreatment (Pre-DET10) or CP2→DET10 treatment had the longest survival (52 vs. 37 days for tumor control mice). CP treatment caused abnormally accumulated urea cycle metabolites and serotonin metabolite hippuric acid in renal tissues that were not seen with DET alone or in combination with CP. ConclusionThe CP and DET combination may be an effective intervention for melanoma with reduced side effects.

Deoxyelephantopin ameliorates lipopolysaccharides (LPS)-induced memory impairments in rats: Evidence for its anti-neuroinflammatory properties

AimNeuroinflammation is a critical pathogenic mechanism of most neurodegenerative disorders especially, Alzheimer's disease (AD). Lipopolysaccharides (LPS) are known to induce neuroinflammation which is evident from significant upsurge of pro-inflammatory mediators in in vitro BV-2 microglial cells and in vivo animal models. In present study, we investigated anti-neuroinflammatory properties of deoxyelephantopin (DET) isolated from Elephantopus scaber in LPS-induced neuroinflammatory rat model. Materials and methodsIn this study, DET (0.625. 1.25 and 2.5 mg/kg, i.p.) was administered in rats for 21 days and those animals were challenged with single injection of LPS (250 μg/kg, i.p.) for 7 days. Cognitive and behavioral assessment was carried out for 7 days followed by molecular assessment on brain hippocampus. Statistical significance was analyzed with one-way analysis of variance followed by Dunnett's test to compare the treatment groups with the control group. Key findingsDET ameliorated LPS-induced neuroinflammation by suppressing major pro-inflammatory mediators such as iNOS and COX-2. Furthermore, DET enhanced the anti-inflammatory cytokines and concomitantly suppressed the pro-inflammatory cytokines and chemokine production. DET treatment also reversed LPS-induced behavioral and memory deficits and attenuated LPS-induced elevation of the expression of AD markers. DET improved synaptic-functionality via enhancing the activity of pre- and post-synaptic markers, like PSD-95 and SYP. DET also prevented LPS-induced apoptotic neurodegeneration via inhibition of PARP-1, caspase-3 and cleaved caspase-3. SignificanceOverall, our studies suggest DET can prevent neuroinflammation-associated memory impairment and neurodegeneration and it could be developed as a therapeutic agent for the treatment of neuroinflammation-mediated and neurodegenerative disorders, such as AD.

Deoxyelephantopin from Elephantopus scaber modulates neuroinflammatory response through MAPKs and PI3K/Akt-dependent NF-κB signaling pathways in LPS-stimulated BV-2 microglial cells

Microglial activation which results in neuroinflammation, plays a great significance in the pathogenesis of neurodegenerative diseases by secreting various neurotoxic factors. Suppression of microglial activation by the natural-derived compounds may ameliorate neurodegenerative processes. The anti-inflammatory activity of deoxyelephantopin (DET) from the ethyl acetate fraction of Elephantopus scaber was studied against LPS-stimulated BV-2 cells. Deoxyelephantopin suppressed the production of nitric oxide and prostaglandin E2 by inhibiting the LPS-induced inducible nitric oxide synthase and cyclooxygenase-2. DET inhibited nuclear translocation of nuclear factor-kappa B (NF-κB) and IκBα phosphorylation by suppressing phosphorylation of PI3K/Akt and mitogen-activated protein kinases (MAPKs) pathways in BV-2 cells. Interestingly, the enhancement of anti-inflammatory cytokines, interleukin (IL)-4 and IL-10 concomitantly with the reduction of pro-inflammatory cytokines (Interferon-γ, IL-1β, IL-2, IL-6, IL-12 and tumor necrosis factor-α), chemokines (CCL21 and CCL5/RANTES) and galectin-3 were found upon DET treatment. Taken together, present study further advocates DET as a potential novel anti-neuroinflammatory agent in the intervention of neurodegenerative diseases.

Phytoagent Deoxyelephantopin and Its Derivative Inhibit Triple Negative Breast Cancer Cell Activity through ROS-Mediated Exosomal Activity and Protein Functions.

A novel plant sesquiterpene lactone derivative, DET derivative (DETD)-35, originating from parental deoxyelephantopin (DET) was previously observed to effectively suppress human triple negative breast cancer (TNBC) MDA-MB-231 cell activity and tumor growth in mice. In this study, the mechanisms underlying the activity of DETD-35 were elucidated. DET and DETD-35 induced reactive oxygen species (ROS) which caused structural damage and dysfunction of mitochondria and increased cytosolic calcium level, subsequently evoking exosome release from the cancer cells. Intriguingly, exosomes induced by both compounds had an atypical function. Cancer cell-derived exosomes commonly show metastatic potential, but upon DET/DETD-35 treatment exosomes showed anti-proliferative activity against MDA-MB-231 cells. Quantitative proteome analysis of TNBC cell-secreted exosomes showed that DET and DETD-35 attenuated the expression of proteins related to cell migration, cell adhesion, and angiogenesis. Furthermore, several exosomal proteins participating in biological mechanisms such as oxidative stress and decrease of transmembrane potential of mitochondria were found deregulated by treatment with either compound. Pretreatment with ROS scavenger, N-acetylcysteine, blockaded DET- or DETD-35-induced oxidative stress and calcium dependent exosome release mechanisms, and also reverted DET- or DETD-35-induced reprogramming exosomal protein expression profiles resulting in attenuation of exosomal toxicity against TNBC cell proliferation. In summary, this study shows that a plant-derived sesquiterpene lactone DET and its analog DETD-35 inhibitory TNBC cell activities through oxidative stress-induced cancer cell releasing exosomes in tandem with alteration of exosomal protein composition and functions. The findings of this study suggest that DETD-35 may be suitable for further development into an anti-TNBC drug.

Deoxyelephantopin and Isodeoxyelephantopin as Potential Anticancer Agents with Effects on Multiple Signaling Pathways.

Cancer is the 2nd leading cause of death worldwide. The development of drugs to target only one specific signaling pathway has limited therapeutic success. Developing chemotherapeutics to target multiple signaling pathways has emerged as a new prototype for cancer treatment. Deoxyelephantopin (DET) and isodeoxyelephantopin (IDET) are sesquiterpene lactone components of “Elephantopus scaber and Elephantopus carolinianus”, traditional Chinese medicinal herbs that have long been used as folk medicines to treat liver diseases, diabetes, diuresis, bronchitis, fever, diarrhea, dysentery, cancer, and inflammation. Recently, the anticancer activity of DET and IDET has been widely investigated. Here, our aim is to review the current status of DET and IDET, and discuss their anticancer activity with specific emphasis on molecular targets and mechanisms used by these compounds to trigger apoptosis pathways which may help to further design and conduct research to develop them as lead therapeutic drugs for cancer treatments. The literature has shown that DET and IDET induce apoptosis through multiple signaling pathways which are deregulated in cancer cells and suggested that by targeting multiple pathways simultaneously, these compounds could selectively kill cancer cells. This review suggests that DET and IDET hold promising anticancer activity but additional studies and clinical trials are needed to validate and understand their therapeutic effect to develop them into potent therapeutics for the treatment of cancer.