Mechanisms of Lian-Gui-Ning-Xin-Tang in the treatment of arrhythmia: Integrated pharmacology and in vivo pharmacological assessment

Study on the underlying mechanism of Poria in intervention of arrhythmia zebrafish by integrating metabolomics and network pharmacology

BACKGROUND

Poria is an herb with both medicinal and dietary application. It has been used in various traditional Chinese patent medicines and medicinal decoctions for the treatment of arrhythmia. However, the specific mechanisms involved in the antiarrhythmic effects of Poria have, until now, remained unknown.

PURPOSE

This present study sought to explore the potential compounds and mechanisms by which Poria ameliorates BaCl2-induced arrhythmia.

METHOD

We initiated by using network pharmacology to predict probable components, targets, and associated signaling pathways before optimizing the extraction process of Poria. We then applied Poria extract to a zebrafish model of BaCl2-induced arrhythmia. We combined network pharmacology and untargeted metabolomic analysis to predict the likely signaling and metabolic pathways governed by Poria. Finally, we verified putative mRNA and metabolite targets of Poria involved in the intervention of arrhythmia by PCR, molecular docking, enzymatic inhibition and targeted metabolomics.

RESULTS

We found that triterpenoids may be the main components of Poria responsible for its effects on arrhythmia, and that the optimal extraction process for its water extract is 9 volumes of water with the 7.5 h first extraction period, and the second extraction period of 1.5 h. Through experimentation, we have found that the water extract of Poria can interfere with BaCl2 induced arrhythmia in zebrafish by significantly increasing the heart rate, reducing the SV-BA distance, and pericardial area, and the degree of cardiomyocyte apoptosis in zebrafish. In addition, PCR validation revealed that Poria can regulate the calcium signaling pathway by upregulating the gene expression levels of ADRB1, HTR7, CALMB1, and PPP3CA. Meanwhile, through molecular docking and enzyme activity inhibition, it was found that the compounds in Poria can bind to ADRB1, HTR7, CALMB1, and PPP3CA, respectively. Targeted metabolism confirmed that Poria can downregulate the synthesis of cAMP in the calcium signaling pathway, as well as the synthesis of valine and isoleucine in valine, leucine, and isoleucine biosynthesis.

CONCLUSION

Overall, our study indicates that Poria exerts its antiarrhythmic effect through regulating the calcium signaling pathway and valine, leucine, and isoleucine biosynthesis. Our findings not only establish a mechanistic framework for elucidating the antiarrhythmic effects of Chinese patent medicine containing Poria, but also provide a medicinal basis for the study of its dual use as medicine and food.

Mechanism investigation of Shi-Xiao-San in treating blood stasis syndrome based on network pharmacology, molecular docking and in vitro/vivo pharmacological validation

ETHNOPHARMACOLOGICAL RELEVANCE

Shixiao San (SXS) is a traditional Chinese formula that has been widely used in clinical practice to treat blood stasis syndromes, such as hyperlipidemia, atherosclerotic, thrombosis and coronary heart disease. However, the effectiveness and mechanism of SXS have not been studied in detail yet.

AIM OF THE STUDY

Current study aimed to identify the compounds in SXS, evaluate the formula efficacies using network pharmacology, molecular docking, and verify the pharmacological effects by in vivo and in vitro experiments.

MATERIALS AND METHODS

The compounds in SXS were analyzed using UPLC-QTOF-MS. Potential target genes for identified compounds were obtained from three databases. DAVID database was used to perform GO and KEGG pathway enrichment analyses. PPI network was constructed to screen core targets. Molecular docking was used to examine interactions between active compounds and potential targets. The mechanism was also verified by model of acute blood stasis rats and human umbilical vein cells.

RESULTS

In total, 45 compounds were identified from SXS. Among the detected phytochemicals, quercetin, isorhamnetin, kaempferol, D-catechin, naringenin and amentoflavone were identified as the active constituents. SXS is primarily involved in the modulation of hypoxic state, vascular regulation, and inflammation response, according to GO and KGG pathway enrichment analysis. A network of protein-protein interactions (PPIs) was constructed and five core targets were identified as VEGFA, AKT1, EGFR, PTGS2, and MMP9. Molecular docking simulation revealed good binding affinity of the five putative targets with the corresponding compounds. SXS reduced HIF-1α and COX-2 levels and increased the eNOS expression levels in hypoxic HUVECs. SXS can reduce the whole blood viscosity in adrenaline induced acute blood stasis rats and relieve blood stasis.

CONCLUSIONS

SXS removes blood stasis might through VEGFA/AKT/eNOS/COX-2 pathway and flavonoids are the main active components in the formula.

Uncovering the Mechanisms of Active Components from Toad Venom against Hepatocellular Carcinoma Using Untargeted Metabolomics

Toad venom, a dried product of secretion from Bufo bufo gargarizans Cantor or Bufo melanostictus Schneider, has had the therapeutic effects of hepatocellular carcinoma confirmed. Bufalin and cinobufagin were considered as the two most representative antitumor active components in toad venom. However, the underlying mechanisms of this antitumor effect have not been fully implemented, especially the changes in endogenous small molecules after treatment. Therefore, this study was designed to explore the intrinsic mechanism on hepatocellular carcinoma after the cotreatment of bufalin and cinobufagin based on untargeted tumor metabolomics. Ultraperformance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS) was performed to identify the absorbed components of toad venom in rat plasma. In vitro experiments were determined to evaluate the therapeutic effects of bufalin and cinobufagin and screen the optimal ratio between them. An in vivo HepG2 tumor-bearing nude mice model was established, and a series of pharmacodynamic indicators were determined, including the body weight of mice, tumor volume, tumor weight, and histopathological examination of tumor. Further, the entire metabolic alterations in tumor after treating with bufalin and cinobufagin were also profiled by UHPLC-MS/MS. Twenty-seven active components from toad venom were absorbed in rat plasma. We found that the cotreatment of bufalin and cinobufagin exerted significant antitumor effects both in vitro and in vivo, which were reflected in inhibiting proliferation and inducing apoptosis of HepG2 cells and thereby causing cell necrosis. After cotherapy of bufalin and cinobufagin for twenty days, compared with the normal group, fifty-six endogenous metabolites were obviously changed on HepG2 tumor-bearing nude mice. Meanwhile, the abundance of α-linolenic acid and phenethylamine after the bufalin and cinobufagin intervention was significantly upregulated, which involved phenylalanine metabolism and α-linolenic acid metabolism. Furthermore, we noticed that amino acid metabolites were also altered in HepG2 tumor after drug intervention, such as norvaline and Leu-Ala. Taken together, the cotreatment of bufalin and cinobufagin has significant antitumor effects on HepG2 tumor-bearing nude mice. Our work demonstrated that the in-depth mechanism of antitumor activity was mainly through the regulation of phenylalanine metabolism and α-Linolenic acid metabolism.