Cucurbitacin E Alleviates Colonic Barrier Function Impairment and Inflammation Response and Improves Microbial Composition on Experimental Colitis Models.

Purpose: Cucurbitacins, which are found in a variety of medicinal plants, vegetables and fruits, were known for their diverse pharmacological and biological activities, including anticancer, anti-oxidative and anti-inflammatory effects. Cucurbitacin E, one of the major cucurbitacins, was recently proved to inhibit inflammatory response. Methods: To explore the therapeutic effects of cucurbitacin E on colitis and the underlying mechanisms, male mice drunk water containing 2.5% dextran sulfate sodium (DSS) to establish colitis model and administrated with cucurbitacin E during and after DSS treatment. The disease activity index was scored and colonic histological damage was observed. Intestinal tight junction and inflammatory response were determined. 16S rRNA and transcriptome sequencing were performed to analyze gut microbiota composition and gene expression, respectively. Results: We found that cucurbitacin E alleviated DSS-induced body weight loss and impaired colonic morphology. Cucurbitacin E decreased the expression of inflammatory cytokines and cell apoptosis, and maintained barrier function. Additionally, cucurbitacin E retrieved DSS-induced alterations in the bacterial community composition. Furthermore, a variety of differentially expressed genes (DEGs) caused by cucurbitacin E were enriched in several pathways including the NFκB and TNF signaling pathways as well as in Th17 cell differentiation. There was a close relationship between DEGs and bacteria such as Escherichia-Shigella and Muribaculaceae. Conclusion: Our results revealed that cucurbitacin E may exert protective effects on colitis via modulating inflammatory response, microbiota composition and host gene expression. Our study supports the therapeutic potential of cucurbitacin E in colitis and indicates that gut microbes are potentially therapeutic targets.

Total cucurbitacins from Herpetospermum pedunculosum pericarp do better than Hu-lu-su-pian (HLSP) in its safety and hepatoprotective efficacy.

The pericarp of Herpetospermum pedunculosum (HPP) has traditionally been used for treating jaundice and hepatitis. However, the specific hepatoprotective components and their safety/efficacy profiles remain unclear. This study aimed to characterize the total cucurbitacins (TCs) extracted from HPP and evaluate their hepatoprotective potential. As a reference, Hu-lu-su-pian (HLSP), a known hepatoprotective drug containing cucurbitacins, was used for comparison of chemical composition, effects, and safety. Molecular networking based on UHPLC-MS/MS identified cucurbitacin B, isocucurbitacin B, and cucurbitacin E as the major components in TCs, comprising 70.3%, 26.1%, and 3.6% as determined by RP-HPLC, respectively. TCs treatment significantly reversed CCl4-induced metabolic changes associated with liver damage in a dose-dependent manner, impacting pathways including energy metabolism, oxidative stress and phenylalanine metabolism, and showed superior efficacy to HLSP. Safety evaluation also showed that TCs were safe, with higher LD50 and no observable adverse effect level (NOAEL) values than HLSP. The median lethal dose (LD50) and NOAEL values of TCs were 36.21 and 15 mg/kg body weight (BW), respectively, while the LD50 of HLSP was 14 mg/kg BW. In summary, TCs extracted from HPP demonstrated promising potential as a natural hepatoprotective agent, warranting further investigation into synergistic effects of individual cucurbitacin components.

Antiproliferative and immunomodulative potential of Citrullus colocynthis and its bioactive compounds in human lymphocytes and lung cells.

ETHNOPHARMACOLOGICAL RELEVANCE: Citrullus colocynthis (L.) Schrad is a member of the Cucurbitaceae plant family which has been used in traditional medicine for the treatment of lung diseases such as asthma and bronchitis. AIM OF THE STUDY: The study was conducted to investigate antiproliferative and immunomodulating effects of C. colocynthis and isolated cucurbitacins on human T lymphocytes and lung epithelial cells in order to evaluate their potential in the treatment of airway diseases. MATERIALS AND METHODS: Different concentrations of an ethanolic extract of C. colocynthis fruits and cucurbitacins B (CuB), E (CuE) and E-glucopyranoside (CuE-Glu) were analysed for their cytotoxicity and immunomodulatory potential on Peripheral Blood Mononuclear Cells (PBMCs) of healthy donors and on the epithelial lung cancer cell line A549. Viability and proliferation were tested using WST1 and CFSE assays. Flow cytometric analysis of AnnexinV/PI staining was used to investigate cell death through apoptosis/necrosis. Effects on regulatory mechanisms of T lymphocytes, such as CD69 and CD25 marker activation, cytokine production of the cytokines interleukin 2 (IL2), tumor necrosis factor α (TNFα) and interferon γ (IFNy) were also analysed via flow cytometry. Influences on the activator protein 1 (AP1), nuclear factor of activated T-cells (NFAT) or nuclear factor 'kappa-light-chain-enhancer' of activated B-cells (NFκB) pathways were analysed in the Jurkat reporter cell line. Cytokine secretion in A549 cells stimulated with virus-like particles was analysed using the bead-based Legendplex™ assay. RESULTS: Non-toxic concentrations of C. colocynthis and CuE-Glu showed dose-dependent effects on viability and proliferation in both T lymphocytes and A549 cells. The extracts inhibited lymphocyte activation and suppressed T cell effector functions, which was also shown by lower production of cytokines IL2, TNFα and IFNy. A dose dependent inhibition of the pathways NFκB, NFAT and AP1 in Jurkat cells could be observed. In A549 cells, especially CuE and CuE-Glu showed inhibitory effects on cytokine production following a simulated viral infection. Unglycosylated cucurbitacins were more effective in suppressing the immune function in lymphocytes than glycosylated cucurbitacins, however this activity is limited to cytotoxic concentrations. CONCLUSION: In our study we could confirm the immunmodulating effect of C. colocynthis and cucurbitacins B, E and E-glucopyranoside in vitro by suppression of different pathways of inflammation and T cell proliferation. Activity in a lung cell model using a virus-like stimulation shows promise for further research regarding cucurbitacins in airway diseases.

Research Progress on Anti-tumor Effect and Mechanism of Cucurbitacins / 中国实验方剂学杂志

Cancer is a major global public health problem. Statistics from the national cancer center of China also show that cancer has become a major disease threatening human health with increasing morbidity and mortality. The occurrence and development mechanism of cancer is complex， involving multiple stages， multiple genes and multiple signaling pathways. Conventional chemoradiotherapy and emerging targeted therapy methods are the main methods in treatment of tumor. However， the quality of life of patients as well as the sustained and effective therapeutic effect are seriously affected due to the toxic side effects and drug resistance. Therefore， it is the global focus to find safe and effective anti-cancer drugs. The research and development and application of anti-cancer herbal medicines such as paclitaxel， vinblastine， podophyllin， ginsenoside and ginseng polysaccharide have brought new hope for the treatment of cancer. Cucurbitacine from Chinese medicine cucurbitaceae plantsare is a kind of highly oxidized tetracyclic triterpene compound with extensive pharmacological effects and complex mechanism. In the family of cucurbitacines， cucurbitin B， D， E and I have been studied most frequently on anticancer effect， and in a large number of studies， they have been found to play an important role in tumor diseases of the digestive system， respiratory system， reproductive system， blood system， urinary system and so on. With significant effect in inhibiting tumor cells proliferation， blocking the cell cycle， inducing apoptosis and autophagy death， inhibiting cell migration and invasion， inhibiting tumor angiogenesis， regulating the levels of reactive oxygen species and regulating immune system， such cucurbitacins are expected to be developed as a new kind of anti-cancer drugs. The authors of this study aim to provide reference for the further research and development of new anti-cancer drugs about cucurbitines by summarizing the anti-tumor effect and mechanism of the cucurbitacins.

Cucurbitacin B inhibits proliferation and invasion of osteosarcoma 143b cells and promotes apoptosis / 肿瘤

Objective: To investigate the effects of cucurbitacin B (CuB) on the proliferation, invasion and apoptosis of osteosarcoma 143B cells, to explore the related molecular mechanisms. Methods: 143B cells were treated with different concentrations of CuB. The proliferation ability of 143B cells was detected by crystal violet staining and colony formation assay. The invasion ability of 143B cells was detected by Transwell chamber assay. The apoptosis rate and cell cycle distribution were detected by flow cytometry (FCM) method. The expression levels of epithelial-mesenchymal transition (EMT)-related markers including Vimentin, Snail and matrix metalloproteinase-9 (MMP-9) mRNAs and proteins were detected by real-time fluorescent quantitative PCR and Western blotting, respectively. The expression levels of apoptosis-related proteins [Bad, cleaved-caspase 3, cleaved-polyadenosine diphosphate ribose polymerase (PARP) and cyclin B1] and protein kinase B (PKB, Akt) signal pathwayrelated proteins [Akt, phospho-Akt (p-Akt), phosphatase and tensin homolog deleted on chromosome ten (PTEN) and phospho-PTEN (p-PTEN)] were detected by Western blotting. Results: Compared with the untreated control group, the proliferation and invasion of 143B cells treated with different concentrations of CuB were significantly inhibited (all P < 0.05). After treatment with 30 or 40 nmol/L CuB, the apoptosis rate of 143B cells was increased (both P < 0.05), the cell cycle was blocked in G2/M phase (both P < 0.01). The expression levels of MMP-9, Vimentin and Snail mRNAs and proteins were remarkably down-regulated (all P < 0.05) in 143B cells treated with CuB. The expression levels of apoptosis-related Bad, cleavedcaspase 3 and cleaved-PARP proteins were remarkably up-regulated (all P < 0.05) in 143B cells treated with CuB, the expression of cell cycle-related cyclin B1 protein was down-regulated (all P < 0.01) in 143B cells treated with CuB. At the same time, CuB reduced the expression level of p-Akt protein and increased the expression level of p-PTEN protein (both P < 0.05). Conclusion: CuB can inhibit the proliferation and invasion of osteosarcoma 143B cells, and promote apoptosis. These effects may be related to Akt pathway impediment and EMT processing attenuation.

Mechanism of cucurbitacin B underlying pressure overload-induced myocardial fibrosis / 中华老年心脑血管病杂志

Objective To study the mechanism of cucurbitacin B (CuB) underlying pressure over load-induced myocardial fibrosis.Methods Sixty C57 mice were divided into sham operation group,CuB treatment group,aorta ligation group,CuB+aorta ligation group (15 in each group).The animals received intragastric gavage (0.2 mg/kg · 2 d) one week after operation and a myocardial fibrosis model of mice was induced by aorta ligation 4 weeks after operation.Microvascular density (MVD) was detected with immunohistochemical staining.Expressions of α-SMA,CD31,CD34,vimentin and endothelial-mesenchymal transition (EndMT) were detected by Western blot with immunofluorescence staining.Results No significant difference was found in cardiac MVD,and expression level of α-SMA,vimentin,CD31 and CD34 between sham operation group and CuB group 4 weeks after operation (P＞0.05).The cardiac MVD and expression level of CD31 and CD34 were significantly lower while the expression level of α-SMA and vimentin was significantly higher in aorta ligation group than in sham operation group 4 weeks after operation (P＜0.05).The cardiac MVD and expression level of CD31 and CD34 were significantly higher while the expression level of α-SMA and vimentin was significantly lower in CuB+aorta ligation group than in aorta ligation group 4 weeks after operation (P＜0.05).Conclusion CuB can attenuate cardiac fibrosis by regulating EndMT.

Effects of cucurbitacin Ⅰ on in vitro proliferation of HaCaT cells and the expression of keratin 17, signal transducer and activator of transcription 3 and vascular endothelial growth factor / 中华皮肤科杂志

Objective To evaluate effects of cucurbitacin Ⅰ on in vitro proliferation of HaCaT cells and the expression of keratin 17 (K17),signal transducer and activator of transcription 3 (STAT3) and vascular endothelial growth factor (VEGF) in cultured HaCaT cells.Methods In vitro cultured HaCaT cells were divided into 6 groups to be treated with cucurbitacin Ⅰ at different concentrations of 0.0125,0.025,0.05 and 0.1 μmol/L (0.0125,0.025,0.05 and 0.1 μmol/L cucurbitacin Ⅰ groups),DMEM containing the same volume of DMSO as 0.1 pmol/L cucurbitacin Ⅰ (DMSO group),DMEM (negative control group) and 10 nmol/L calcipotriol (positive control group),respectively.Cell counting kit-8 (CCK8) assay was performed to assess in vitro cellular proliferative activity after 12-,24-,36-hour treatment,reverse transcription (RT)-PCR to measure the mRNA expression of K17 and VEGF in HaCaT cells after 24-hour treatment,and Western blot analysis to determine the protein expression of K17,STAT3,phosphorylated-STAT3 (p-STAT3) and VEGF after 24-hour treatment.Statistical analysis was carried out by one-way analysis of variance (ANOVA),repeated measures ANOVA,Student-Newman-Keuls (SNK)-q test and Pearson correlation analysis.Results The proliferative activity of HaCaT cells started to decrease after 12-hour treatment with cucurbitacin Ⅰ at the concentration of 0.0125 μmol/L.When the concentration of cucurbitacin Ⅰ increased up to 0.1 μmol/L,the cell proliferation rates were inhibited by 43.00％ ± 2.11％ and 48.98％ ± 2.27％ after 24-and 36-hour treatment respectively.Compared with the negative control group,cucurbitacin Ⅰ at different concentrations all could inhibit in vitro proliferation of HaCaT cells (all P ＜ 0.05),and the inhibitory effects increased gradually with the increase of cucurbitacin Ⅰ concentration and treatment duration.After 24-hour treatment,the mRNA expression of K17 and VEGF and the protein expression of K17,VEGF and P-STAT3 were significantly decreased along with the increase of concentration of cucurbitacin Ⅰ (all P ＜ 0.05).Conclusion Cucurbitacin Ⅰ can inhibit in vitro proliferation of HaCaT cells,and down-regulate the mRNA expression of K17 and VEGF and protein expression of K17,VEGF and P-STAT3.

Low Nanomolar Cucurbitacin-I Induces G2 / M Phase Arrest and Apoptosis in Gastric Cancer Cells and the Underlying Mechanism / 胃肠病学

Background:Upon inhibition of STAT3 signaling pathway,cucurbitacin-I elicits anticancer effect in various malignancies. However,the anticancer effect and underlying mechanism of cucurbitacin-I in gastric cancer is still elusive. Aims:To explore the effect of low nanomolar cucurbitacin-I on cell proliferation,cell cycle and apoptosis in human gastric cancer cells and the underlying mechanism in vitro. Methods:Human gastric adenocarcinoma cell lines AGS and HGC-27 were treated with cucurbitacin-I at low nanomolar concentration. The anti-proliferative effect of cucurbitacin-I was detected by CCK-8 assay and colony formation assay. Flow cytometry was used to assess the cell cycle and apoptosis. Expressions of cell cycle-related proteins,as well as activation of related pathways such as caspase-3 / PARP apoptotic pathway,STAT3, GADD45α and JNK/ p38 MAPK signaling pathways were determined by Western blotting. Results:Cucurbitacin-I markedly inhibited the growth of gastric cancer cells at low nanomolar concentration by inducing G2 / M phase arrest and apoptosis via a STAT3-independent manner. Furthermore,it was revealed that the anticancer effect of cucurbitacin-I was associated with up-regulation of GADD45α,activation of JNK/ p38 MAPK signaling pathway and the subsequent apoptotic events. Conclusions:The present study provides new insights into the mechanism of anticancer effect of cucurbitacin-I, supporting cucurbitacin-I as an attractive therapeutic drug in gastric cancer.