The combination of tetracyclines effectively ameliorates liver fibrosis via inhibition of EphB1/2.

Eph receptor tyrosine kinase EphB1/2 contributes to the development of liver fibrosis, suggesting the rationale that EphB1/2 inhibitors may be effective in liver fibrosis therapy. Since tetracycline antibiotics were recently demonstrated as EphB kinase inhibitors, in present study we investigated their therapeutic potential against liver fibrosis. Our results showed that the tetracycline combination of demeclocycline (D), chlortetracycline (C), and minocycline (M) inhibited the activation of hepatic stellate cells (HSCs) in vitro and alleviated CCl4-induced animal model of liver fibrosis in vivo. Mechanistically, DCM combination inhibited EphB1/2 phosphorylation and subsequent activation of the MAPK signaling. Moreover, we found that short-term and low-dose DCM combination treatment decreased tissue inflammation and improved liver fibrosis in mice. Thus, our study indicates that tetracyclines may be repurposed for the treatment of liver fibrosis.

Neddylation of EphB1 Regulates Its Activity and Associates with Liver Fibrosis.

Liver fibrosis is a pathological process characterized by the excessive synthesis and accumulation of extracellular matrix proteins (ECMs) contributed mainly by the activated hepatic stellate cells (HSCs). Currently, no direct and effective anti-fibrotic agents have been approved for clinical use worldwide. Although the dysregulation of Eph receptor tyrosine kinase EphB2 has been reported to associate with the development of liver fibrosis, the involvement of other Eph family members in liver fibrosis remains underexplored. In this study, we found that the expression of EphB1 is significantly increased accompanying remarkable neddylation in activated HSCs. Mechanistically, this neddylation enhanced the kinase activity of EphB1 by the prevention of its degradation, thereby promoting the proliferation, migration, and activation of HSCs. Our findings revealed the involvement of EphB1 in the development of liver fibrosis through its neddylation, which provides new insights into the Eph receptor signaling and a potential target for the treatment of liver fibrosis.

Demethylzeylasteral attenuates hepatic stellate cell activation and liver fibrosis by inhibiting AGAP2 mediated signaling.

BACKGROUND: Liver fibrosis is a common cause of chronic liver disease. If left untreated, it can ultimately develop into liver cirrhosis or hepatocellular carcinoma. However, a direct antifibrotic therapy is currently unavailable. A re-examination of existing chemicals might be a potential strategy for finding more lead compounds against liver fibrosis. Demethylzeylasteral (T-96), a naturally occurring bioactive compound found in Tripterygium wilfordii Hook. f. (TwHf) possesses multiple pharmacological properties. However, its antifibrotic potential has not yet been fully evaluated. PURPOSE: This study aimed to investigate the antifibrotic properties of T-96 and its underlying molecular mechanisms. METHODS: The antifibrotic properties of T-96 were investigated in three types of hepatic stellate cells (HSCs) and in a CCl4-induced liver fibrosis mouse model. The effect of T-96 on the proliferation, migration, and activation of HSCs was detected using CCK-8 and scratch/wound healing assays. Hepatic inflammation and fibrosis were evaluated by H&E, Masson's trichrome stain, and Sirius Red staining. The expression of inflammatory and fibrogenic genes was detected by quantitative real-time PCR (qRT-PCR) and western blotting. RNA sequencing (RNA-seq) was performed to explore the potential molecular mechanisms mediating the antifibrotic effect of T-96, which was verified by dual-luciferase reporter assay, qRT-PCR, western blotting, immunofluorescence, and immunoprecipitation analysis. RESULTS: The T-96 treatment significantly suppressed the proliferation, migration, and activation of HSCs in vitro. The administration of T-96 attenuated hepatic injury, inflammation, and fibrosis progression in mice with CCl4-induced liver fibrosis. In addition, the RNA-seq of fibrotic liver tissues and subsequent functional verification indicated that the key mechanisms of the antifibrotic effect of T-96 were mediated by suppressing the expression of AGAP2 (Arf GAP with GTPase-like domain, ankyrin repeat and PH domain 2), inhibiting the subsequent phosphorylation of focal adhesion kinase (FAK) and protein kinase B (AKT), and finally reducing the expression of fibrosis-related genes. CONCLUSION: Our results provide the first insight that T-96 exerts potent antifibrotic effects both in vitro and in vivo by inhibiting the AGAP2 mediated FAK/AKT signaling axis, and that T-96 may serve as a potential therapeutic candidate for the treatment of liver fibrosis.

Rotundic Acid Regulates the Effects of Let-7f-5p on Caco2 Cell Proliferation.

BACKGROUND & OBJECTIVE: Nowadays, the interaction between natural products and microRNAs provides a promising field for exploring the chemopreventive agents for various cancers. As a member of microRNAs, the expression of let-7f-5p is universally downregulated in Colorectal Cancer (CRC). The present study aimed to uncover the function of let-7f-5p in the proliferation of human colon cancer cell line Caco2 and explored chemopreventive agents from natural resources that can prevent the development of CRC. METHODS: Herein, Caco2 cells were transfected with let-7f-5p mimic and inhibitor to manipulate let-7f-5p levels, and the expression of let-7f-5p was performed by RT-qPCR. Next, we determined how let-7f-5p regulates Caco2 cell proliferation by using MTT, wound-healing, cell cycle, and colony formation assays. Besides, to further understand the effect of let-7f-5p, we evaluated the protein level of AMER3 and SLC9A9 by using western blotting assays. RESULTS: The results showed a suppressive function of let-7f-5p on Caco2 cell proliferation and then put forward a triterpenoid (Rotundic Acid, RA) which significant antagonized the effect of cell proliferation, restitution after wounding, and colony formation caused by let-7f-5p. Moreover, the western blot results further indicated that the inhibitory effect of RA might be due to its suppressive role in let-7f-5p-targeted AMER3 and SLC9A9 regulation. CONCLUSION: Our validation study results confirmed that let-7f-5p was a potent tumor suppressor gene of Caco2 cell proliferation, and RA showed as a regulator of the effect of let-7f-5p on cell proliferation and then could be a potential chemopreventive agent for CRC treatment.

Post-transcriptional Gene Regulation in Colitis Associated Cancer.

Colitis-associated cancer (CAC) has been linked to microRNA (miRNA) aberrant expression elicited by inflammation. In this study, we used the AOM/DSS-induced CAC mice model to explore the ectopic expression of miRNAs in the precancerous stage of CAC. As a result, we found that miR-31-5p, miR-223-3p, and let-7f-5p were dysregulated during the development of intestinal dysplasia. Subsequently, we first identified the role of these three miRNAs in CAC. Adenomatous polyposis coli (APC) was revealed as a new target of miR-223-3p, and solute carrier family 9- subfamily A-member 9 (SLC9A9) and APC membrane recruitment protein 3 (AMER3) were suggested as two new targets for let-7f-5p. For miR-31-5p, we proved that it can target LATS2 mRNA so as to modulate Hippo pathway in Caco2 cells. Second, to examine if targeting these three miRNAs would lead to CAC prevention, pedunculoside, a natural triterpene glycoside capable of rescuing the down-regulation of LATS2 and APC caused by either miR-31-5p or miR-223-3p overexpression, respectively, was used in the in vivo AOM/DSS-induced CAC model. The results showed that pedunculoside (25 mg/kg) substantially mitigated the damage to mice intestine caused by DSS/AOM. These results suggested that miRNAs-elicited post-transcriptional regulation is involved in the pathogenesis of CAC, and CAC can be prevented through targeting key miRNAs that are ectopically expressed in CAC.

Antiproliferative steroidal glycosides from rhizomes of Polygonatum sibiricum.

Screening assays showed that total glycoside-rich fraction (TG) of rhizomes of Polygonatum sibiricum unveiled remarkable anti-proliferative activities against three cancer cell lines (A549, HepG2, and Caco2). Activity-guided isolation of TG afforded seven undescribed steroidal glycosides (polygonosides 1-7), along with 24 known glycosides. Their structures were established by 1D and 2D NMR spectroscopic analyses, high-resolution mass spectrometry, and chemical evidence. The isolated steroidal glycosides were tested for their antiproliferative activities against A549, HepG2, and Caco2 cells. Compounds 8, 10, 11, and 16 possessed stronger anticancer activities against A549 cells than the positive control Bay (25.8 µM), with IC50 values ranging from 5.8 to 24.2 µM. Compound 10 reduced the expression of Blc-2 and pro-caspase3 and increased the production of Bax as determined by western blotting. Molecular docking experiment suggested that 10 bound stably to the BH3-binding groove of the Bcl-2 protein by hydrogen bond interactions. These compounds could be candidates for anticancer agents with cytotoxic activity.

Extract of Ilex rotunda Thunb alleviates experimental colitis-associated cancer via suppressing inflammation-induced miR-31-5p/YAP overexpression.

BACKGROUND: Ilex rotunda Thunb is a traditional medicine used in China treating colitis clinically. Triterpenoids is one of its main components. However, the detailed pharmacological activity and the component responsible for its clinical effects are still elusive. PURPOSE: To test the in vivo colitis-associated cancer (CAC) preventive effect of the water fraction extracted from the roots of I. rotunda, and to evaluate its microRNA (miRNA)-related mechanism. STUDY DESIGN AND METHODS: Male or female C57BL/6 mice (12 weeks of age) were used to construct the azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced CAC. 12.5 mg/kg and 25.0 mg/kg of the standardized water extract of I. rotunda (WIR), being equal to 4.29 and 8.58 g of the raw medicine respectively, were adopted to treat the AOM/DSS-induced CAC from the fourth week and continued for 5 weeks. Mice were killed two weeks after the end of the last round of DSS by cervical dislocation. RESULTS: The chemical analysis of WIR revealed the presence of 21 compounds. The syringing and caffeic acid (1-hydroxyl-4-O-ß-D-glucopyranosylprenyl)-ester are the main components of WIR, counting for 8.27% and 5.71% of the water extract respectively. The levels of miR-31-5p were up-regulated in both thp1 and Caco2 cells (p < 0.05) stimulated by either IL-6 or TNF-α, and WIR could restore miR-31-5p levels in the IL-6/TNF-α-stimulated thp-1 and Caco2 cells. Furthermore, WIR decreased TNF-α and IL-6 levels in PMA-differentiated thp-1 cells stimulated by LPS via NF-κB pathway (p < 0.05), suggesting that WIR could restore miR-31-5p expression via down-regulating IL-6 and TNF-α levels. In vivo study showed that oral administration of WIR (25 mg/kg) produced a significant inhibition on the atypical hyperplasia, as well as the release and the expression of IL-6 and TNF-α in the colon tissue. The in vivo transcription of other pro-inflammatory mediators such as iNOS, IL-11, and IL-17A were also attenuated by WIR administration (25 mg/kg, p < 0.05). Meanwhile, WIR (25 mg/kg) restored the miR-31-5p level which was up-regulated in the CAC model group, and ectopic expressions of the miR-31-5p down-stream LATS2 and YAP genes in the hippo pathway were also modulated by the WIR (25 mg/kg) treatment. CONCLUSION: The present study suggests that WIR exerts intestinal anti-inflammatory and CAC preventive effects in an experimental CAC mouse model. The CAC preventive effect can be attributed to the suppression of hippo pathway activated by the inflammatory cytokines, indicating that WIR can be potentially used as an herbal product for CAC prevention. Therefore, there is an emergent need for further evaluation of the main components in WIR to determine the definite bioactive component responsible for the CAC preventive activity.

Natural CAC chemopreventive agents from Ilex rotunda Thunb.

Colitis-associated cancer (CAC) is one of the most serious complications of inflammatory bowel disease. The pathogenesis of CAC is complicated and so far elusive, and the anti-inflammatory effect does not assure CAC preventive activity, making it difficult to discover CAC preventive drugs. In this study, we report the CAC preventive effect of the ethyl acetate (EIR) of Ilex rotunda Thunb., a traditional Chinese herbal medicine being clinically used to treat intestinal disease. We also report the results of screening for CAC preventive agents from EIR via a nuclear factor-kappa B (NF-κB) translocation model in Caco2 cells, since activated NF-κB can be used by tumor cells at the early stage of tumorigenesis. Twenty-four components were isolated from EIR and identified by multiple chromatography and spectral analysis. MTT experiments in IEC-6 and RAW264.7 cells showed that all 24 compounds were toxic-free to normal cell lines. Furthermore, compound rotundic acid (RA) (19) exhibited an inhibitory effect on LPS-induced NF-κB translocation in Caco2 cells. Moreover, RA did not induce apoptosis in Caco2 tumor cells while possessing an anti-inflammatory effect both in immune and intestinal epithelium cells (RAW264.7 and IEC-6 cells, respectively). Removing RA (19) and its 28-O-glucopyranoside (17) from EIR definitely undermined the in vivo CAC preventive activity of EIR. Therefore, the current study suggested that RA (19) could be a potential therapeutic agent against CAC.

High Performance Liquid Chromatography Determination and Optimization of the Extraction Process for the Total Alkaloids from Traditional Herb Stephania cepharantha Hayata.

Stephania cepharantha Hayata is a traditional Chinese herbal medicine used to treat lung cancer, and its alkaloids, especially cepharanthine (CEP), were reported to be its effective ingredients. Therefore, the extraction of potential antitumor ingredients from the plant was of interest. We first explored the optimized solvent extraction of antitumor agents from S. cepharantha Hayata guided by an in vitro antitumor activity assay. The solvent for extraction and its concentration, the liquid to material ratio, extraction duration, particle size, macerating time, and the frequency of extraction were investigated using a single-factor experiment. An orthogonal design (L9, 34) was constructed to determine the suitable extraction conditions. The crude extract was then purified sequentially by macroporous adsorption resins (MR) for the enrichment of CEP. Under these optimal conditions, the yield of total alkaloids in the herbs was 3.4%, whereas the CEP content was 2.9%. Total alkaloids exhibited significant anti-proliferative activities in the A549 cell line. Our study provides means for the further development and use of the antitumor components from S. cepharantha, which has potential for application in the pharmaceutical industry.

Lico A Causes ER Stress and Apoptosis via Up-Regulating miR-144-3p in Human Lung Cancer Cell Line H292.

During our study on the bioactivities of natural flavonoids, we found that the total flavonoids (TFs) and the main constituent of it, licochalcone A (lico A), activated unfolded protein response (UPR) and induced autophagy and thereby apoptosis in H292 cells. MicroRNAs, such as the tumor repressor miR-144-3p, were reported to be differentially expressed in lung cancer cells and were linked to ER stress, autophagy, and apoptosis. However, the underlying miRNA-based mechanism for lico A modulating proliferation, autophagy and apoptosis in lung cancer cells is elusive. In this study, we found that miR-144-3p was down-regulated in H292 cells comparing to normal embryonic lung cells WI-38, and lico A (10 µM) could increase miR-144-3p level in H292 cells. Knockdown of miR-144-3p significantly abrogated the apoptosis and proliferation-inhibiting effects of lico A, and lico A could enhance the proliferation-inhibiting effect and apoptosis induced by miR-144-3p overexpression. Moreover, overexpression miR-144-3p could induce ER stress by down-regulating Nrf2, and lico A enhanced the Nrf2 down-regulation caused by miR-144-3p overexpression. Co-transfection experiments showed that lico A potentially increased the dicing of pre-miR-144 so as to increase the mature miR-144-3p level. Interestingly, high level of lico A (40 µM) up-regulated CHOP protein, but failed to increase the downstream genes levels of CHOP, including Bim and Bcl-2 in H292 cells. Docking studies indicated that CHOP-mediated pathway was potentially blocked by high dose of lico A. Our results suggested that lico A could cause UPR, autophagy and apoptosis, and the underlying mechanism involved up-regulation of miR-144-3p, and increased lico A level would also increase the potential for lico A inhibiting CHOP-dependent apoptosis in H292 cells.

Undescribed phenylethyl flavones isolated from Patrinia villosa show cytoprotective properties via the modulation of the mir-144-3p/Nrf2 pathway.

Five previously undescribed phenylethyl flavones, together with six known flavones, were isolated from the whole plant of Patrinia villosa. It is the first report of natural flavones bearing phenylethyl groups. Their structures were elucidated by the interpretation of 1D and 2D NMR data. The absolute configurations of the previously undescribed phenylethyl flavones were deduced by analysis of the ECD data. All isolates were investigated for their cytoprotective effects against hydrogen peroxide (H2O2)-induced oxidative damage in Caco2 cells for the first time. Moreover, the mRNA expression levels of heme oxygenase-1 (HO-1) and NAD(P)H:quinine oxidoreductase 1 (NQO1), and the expression for mir-144-3p/Nrf2 pathway in Caco2 cells were examined by RT-qPCR analysis. As a result, compound 5 showed most potent cytoprotective activity via modulating mir-144-3p/Nrf2 pathway and thereby scavenging of intracellular ROS in vitro.

Four new hybrid polyketide-terpenoid metabolites from the Penicillium sp. SYPF7381 in the rhizosphere soil of Pulsatilla chinensis.

A search for cytotoxic agents from cultures of the Penicillium sp., isolated from the rhizosphere soil of Pulsatilla chinensis, led to the isolation of four new hybrid polyketide-terpenoid metabolites (1-4), together with fourteen known compounds (5-18). Using a bioassay-guided fractionation approach, eighteen compounds were obtained from the ethyl acetate extract of this fungus. Structure elucidation was achieved by extensive analysis of spectroscopic data (1D/2D NMR, HRESIMS and IR). The absolute configurations of compounds 1-4 were determined by means of electronic circular dichroism (ECD) calculation. Compounds 1-4, 7-9, 11, 12, 14 and 17 were tested for their cytotoxicity against HL-60, THP-1 and Caco2 cell lines. Compound 1 showed potent cytotoxic capability against HL-60, THP-1 and Caco2 cell with IC50 values of 3.4µM, 4.3µM, 10.5µM, and compound 2 showed significant inhibiting activities against HL-60 cell line and THP-1 cell line (IC50=7.9µM, 11.3µM, respectively), using 5-fluorouracil as the positive drug with IC50 values of 6.4µM, 4.4µM, 56.6µM for HL-60, THP-1 and Caco2 cells, respectively. And compound 1 showed antibacterial activity toward Bacillus cereus (IC50=49µg/mL, IC90=111µg/mL) and Bacillus subtilis (IC50=10µg/mL, IC90=85µg/mL).