In vitro Screening of Traditional Chinese Medicines Compounds Derived with Anti-encephalomyocarditis Virus Activities

Curcumol inhibits EMCV replication by activating CH25H and inhibiting the formation of ROs

BACKGROUND

Zedoary turmeric oil extracted from the roots of curcuma (Curcuma aeruginosa Roxb.) is used for the treatment of myocarditis in China. EMCV infection causes abortion in pregnant sows and myocarditis in piglets. Our previous studies demonstrated that curcumol significantly increased the expression of IFN-β in EMCV infected HEK-293T cells. The present results showed that curcumol inhibits EMCV replication by interfering the host cell cholesterol homeostasis and reducing ROs production through activation of the JAK/STAT signaling pathway.

METHOD

This study was designed to explore whether curcumol can inhibit the replication of encephalomyocarditis viruses (EMCV) in cell culture. The expression level of JAK1, IRF9, STAT2, P-STAT2, CH25H, PI4KA and OSBP in EMCV-infected HEK-293T cells treated with curcumol, ribavirin or hydroxypropyl-β-CD (HPCD) were determined by Western blotting (WB). The cholesterol level in EMCV infected HEK-293T cells treated with curcumol and HPCD were detected using Amplex™ Red Cholesterol Assay Kit. The antiviral effects of curcumol and HPCD on EMCV were also quantitatively detected by real-time fluorescence quantitative PCR (q-PCR). The amount and morphology of ROs were observed by transmission electron microscopy (TEM).

RESULTS

The results demonstrated that curcumol significantly (P < 0.05) increased the expression of JAK1, IRF9, P-STAT2 and CH25H proteins, while that of STAT2, PI4KA and OSBP were remained unchanged. Compared with virus group (0.134 μg.μg^-1 proteins), the total cholesterol level was significantly (P < 0.05) reduced by curcumol (0.108 μg.μg^-1 proteins) and HPCD (0.089 μg.μg^-1 proteins). Compared with virus group (88237 copies), curcumol (41802 copies) and HPCD (53 copies) significantly (P < 0.05) reduced EMCV load. Curcumol significantly reduced the production of ROs in EMCV-infected HEK-293T cells and activated CH25H through the JAK/STAT signaling pathway.

CONCLUSION

Curcumol inhibited EMCV replication by affecting the cholesterol homeostasis and the production of ROs in HEK-293T cell.

A novel strategy for optimal component formula of anti-PRRSV from natural compounds using tandem mass tag labeled proteomic analyses

BACKGROUND

Porcine Reproductive and Respiratory Syndrome (PRRS) is one of the most important porcine viral diseases which have been threatening the pig industry in China. At present, most commercial vaccines fail to provide complete protection because of highly genetic diversity of PRRSV strains. This study aimed to optimize a component formula from traditional Chinese medicine(TCM)compounds with defined chemical characteristics and clear mechanism of action against PRRSV.

METHODS

A total of 13 natural compounds were screened for the anti-PRRSV activity using porcine alveolar macrophages (PAMs). Three compounds with strong anti-PRRSV activity were selected to identify their potential protein targets by proteomic analysis. The optimal compound formula was determined by orthogonal design based on the results of proteomics. MTT assay was used to determine the maximum non-cytotoxic concentration (MNTC) of each compound using PAMs. QPCR and western blot were used to investigate the PRRSV N gene and protein expression, respectively. The Tandem Mass Tag (TMT) technique of relative quantitative proteomics was used to detect the differential protein expression of PAMs treated with PRRSV, matrine (MT), glycyrrhizic acid (GA) and tea saponin (TS), respectively. The three concentrations of these compounds with anti-PRRSV activity were used for orthogonal design. Four formulas with high safety were screened by MTT assay and their anti-PRRSV effects were evaluated.

RESULTS

MT, GA and TS inhibited PRRSV replication in a dose-dependent manner. CCL8, IFIT3, IFIH1 and ISG15 were the top four proteins in expression level change in cells treated with MT, GA or TS. The relative expression of IFIT3, IFIH1, ISG15 and IFN-β mRNAs were consistent with the results of proteomics. The component formula (0.4 mg/mL MT + 0.25 mg/mL GA + 1.95 μg/mL TS) showed synergistic anti-PRRSV effect.

CONCLUSIONS

The component formula possessed anti-PRRSV activity in vitro, in which the optimal dosage on PAMs was 0.4 mg/mL MT + 0.25 mg/mL GA + 1.95 μg/mL TS. Compatibility of the formula was superposition of the same target with GA and TS, while different targets of MT. IFN-β may be one of the targets of the component formula possessed anti-PRRSV activity.

Curcumol inhibits encephalomyocarditis virus by promoting IFN-β secretion

Background

Encephalomyocarditis virus (EMCV) infection can cause reproductive failure in sows and acute myocarditis and sudden death in piglets. It has caused huge economic losses to the global pig industry and that is why it is necessary to develop effective new treatment compounds. Zedoary turmeric oil has been used for treating myocarditis. Curcumol extracted from the roots of curcuma is one of the main active ingredient of zedoary turmeric oil. The anti-EMCV activity of curcumol along with the molecular mechanisms involved with a focus on IFN-β signaling pathway was investigated in this study.

Method

3-(4,5-dimethyithiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to determine the maximum non-toxic concentration (MNTC), 50% cytotoxic concentration (CC₅₀), maximum inhibition rate (MIR) and 50% effective concentration (EC₅₀) against EMCV. Through EMCV load, the anti-viral effect of curcumol was quantitatively determined using real-time quantitative PCR (qPCR). The effect of curcumol on the expression of IFN-β was investigated using real-time quantitative PCR and ELISA. Western blot was used to determine the amounts of MDA5, MAVS, TANK, IRF3 and P-IRF3 proteins in human embryonic kidney 293 T (HEK-293 T) cells infected with EMCV.

Results

The results of MTT showed that compared with the ribavirin positive control group, the maximum inhibition ratio (MIR) of curcumol was greater but the selection index (SI) value was much smaller than that of ribavirin. The results of qPCR showed that curcumol and ribavirin significantly reduced the replication of EMCV in HEK-293 T cells. The curcumol (0.025 mg/mL) treatment has significantly increased IFN-β mRNA expression in the EMCV-infected HEK-293 T cells while ribavirin treatment did not. The results of ELISA showed that curcumol (0.025 mg/mL and 0.0125 mg/mL) has significantly increased the expression of IFN-β protein in EMCV-infected HEK-293 T cells. The results of Western blot showed that curcumol can inhibit the degradation of TANK protein mediated by EMCV and promote the expression of MDA5 and P-IRF3, while the protein expression level of MAVS and IRF3 remain unchanged.

Conclusion

Curcumol has biological activity against EMCV which we suggest that IFN-β signaling pathway is one of its mechanisms.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12917-021-03015-4.

Matrine: A review of its pharmacology, pharmacokinetics, toxicity, clinical application and preparation researches

ETHNOPHARMACOLOGICAL RELEVANCE

"Dogel ebs" was known as Sophora flavescens Ait., which has been widely utilized in the clinical practice of traditional Chinese Mongolian herbal medicine for thousands of years. Shen Nong's Materia Medica (Shen Nong Ben Cao Jing in Chinese pinyin) recorded that it is bitter in taste and cold in nature with the effect of clearing heat and eliminating dampness, insecticide, diuresis. Due to its extensive application in the fields of ethnopharmacological utilization, the pharmaceutical researches of Sophora flavescens Ait.s keeps deepening. Modern pharmacological studies have exhibited that matrine, which is rich in this traditional herbal medicine, mediates its main biological properties.

AIMS OF THE REVIEW

This review aimed at summarizing the latest and comprehensive information of matrine on the pharmacology, pharmacokinetics, toxicity, clinical application and preparation researches to explore the therapeutic potential of this natural ingredient. In addition, outlooks and perspective for possible future researches that related are also discussed.

MATERIALS AND METHODS

Related information concerning matrine was gathered from the internet database of Google scholar, Pubmed, ResearchGate, Web of Science and Wiley Online Library with the keywords including "matrine", "pharmacology", "toxicology" and "pharmacokinetics", "clinical application", etc. RESULTS: Based on literatures, matrine has a variety of pharmacological effects, including anti-cancer, anti-inflammatory, anti-microbial, detoxification and so on. Nevertheless, there are still some doubts about it due to the toxicity and questionable bioavailability that does exist.

CONCLUSIONS

Future researches directions probably include elucidate the mechanism of its toxicity and accurately tracing the in vivo behavior of its drug delivery system. Without doubt, integration of toxicity and efficiency and structure modification based on it are also pivotal methods to enhance pharmacological activity and bioavailability.