A High Content Screening Assay to Identify Compounds with Anti-Epithelial-Mesenchymal Transition Effects from the Chinese Herbal Medicine Tong-Mai-Yang-Xin-Wan

Tongmai Yangxin Pill combined with metoprolol or metoprolol alone for the treatment of symptomatic premature ventricular complex: a multicenter, randomized, parallel-controlled clinical study

OBJECTIVE

To investigate the effects of Tongmai Yangxin Pill (TMYXP) combined with metoprolol tartrate or metoprolol alone for the treatment of premature ventricular complex (PVC) in patients with symptomatic frequent PVC.

METHODS

A total of 584 patients with symptomatic frequent PVC were randomly assigned (in a 1:1 ratio) into two groups: study group [n = 292, TMYXP (40 pills twice/day, orally) combined with metoprolol tartrate (25 mg twice/day, orally)] and control group [n = 292, metoprolol tartrate (25 mg twice/day, orally) plus placebo pill (40 pills twice/day, orally)]. The total treatment period was eight weeks.

RESULTS

After eight weeks of treatment, the total effective rate of reduction of PVC in the study group and the control group were 76.4% and 51.4%, respectively (P < 0.001). TMYXP combined with metoprolol tartrate demonstrated a significantly greater reduction of the frequency of PVCs compared with the metoprolol tartrate alone (-4537 times/24 h vs. -3013 times/24 h, P < 0.001). The study group also showed a better result compared with the control group with respect to PVC related symptoms. In terms of New York Heart Association classification improvement, the total effective rates were 21.9% in the study group and 12.4% in the control group ( P < 0.05). Both the study group and the control group exhibited improvements in echocardiographic indexes. Left ventricular ejection fraction was significantly improved in the study group compared with the control group ( P < 0.05). There was no significant difference in the incidence of adverse events between the two groups.

CONCLUSIONS

Compared with metoprolol tartrate alone, TMYXP combined with metoprolol tartrate could more effectively reduce the frequency of PVC and alleviated PVC related symptoms, and improve cardiac function in patients with symptomatic PVC.

Epithelial-Mesenchymal Transition (EMT) as a Therapeutic Target

Metastasis is the spread of cancer cells from the primary tumour to distant sites and organs throughout the body. It is the primary cause of cancer morbidity and mortality, and is estimated to account for 90% of cancer-related deaths. During the initial steps of the metastatic cascade, epithelial cancer cells undergo an epithelial-mesenchymal transition (EMT), and as a result become migratory and invasive mesenchymal-like cells while acquiring cancer stem cell properties and therapy resistance. As EMT is involved in such a broad range of processes associated with malignant transformation, it has become an increasingly interesting target for the development of novel therapeutic strategies. Anti-EMT therapeutic strategies could potentially not only prevent the invasion and dissemination of cancer cells, and as such prevent the formation of metastatic lesions, but also attenuate cancer stemness and increase the effectiveness of more classical chemotherapeutics. In this review, we give an overview about the pros and cons of therapies targeting EMT and discuss some already existing candidate drug targets and high-throughput screening tools to identify novel anti-EMT compounds.

Tongmai Yangxin pill reduces myocardial no-reflow by regulating apoptosis and activating PI3K/Akt/eNOS pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Tongmai Yangxin pill (TMYX) is derived from the Zhigancao decoction recorded in Shang han lun by Zhang Zhongjing during the Han dynasty and was further improved by Professor Ruan Shiyi, a cardiovascular expert at Tianjin University of Traditional Chinese Medicine. TMYX is used for the clinical treatment of chest pain, heartache, and qi-yin-deficiency coronary heart disease and can improve vascular endothelial function in patients with angina pectoris or coronary heart disease by up-regulating nitric oxide activity and then regulating vascular tension. Whether TMYX can further improve myocardial no-reflow by up-regulating NO activity and then dilating blood vessels remains unclear.

AIM OF THE STUDY

This study aimed to reveal whether TMYX can further improve myocardial NR by up-regulating NO activity and then dilating blood vessels. The mechanism underlying PI3K/Akt/eNOS pathway activation and apoptosis regulation is also explored.

MATERIALS AND METHODS

The left anterior descending coronary arteries of healthy adult male SD rats were ligated to establish a NR model. The rats were assigned to 14 groups: control, sham, NR, TMYX (4.0 g/kg), sodium nitroprusside (SNP), Tongxinluo capsule (TXL), PI3K blocker (LY), TMYX + LY, SNP + LY, TXL + LY, eNOS blocker (L-NAME), TMYX + L-NAME, SNP + L-NAME, and TXL + L-NAME groups. Cardiac function was measured through echocardiography. Thioflavin S, Evans Blue, and TTC staining were adopted to evaluate NR and ischemic areas. Cell inflammation degree and edema were assessed by hematoxylin-eosin staining. Automated biochemical analyzer and kit were used to detect the activities of myocardial oxidants, including reactive oxygen species, super oxide dismutase, malonaldehyde, and NO. The expression levels of genes and proteins in the PI3K/Akt/eNOS signaling pathway and apoptosis were detected via real-time fluorescence quantitative PCR and Western blot analysis, respectively. A microvascular tension sensor was adopted to detect coronary artery diastolic function in vitro.

RESULTS

TMYX reduced NR and ischemic areas; suppressed LV-mass; enhanced EF, FS, LVOT peak, and LVSV; and improved cardiac structure and function. Moreover, it decreased creatine kinase (CK), CK-MB, and lactic dehydrogenase activities. TMYX increased NO and super oxide dismutase activities; inhibited malonaldehyde activity; reduced muscle fiber swelling and inflammatory cell infiltration; and improved vasodilation in vitro. In the NR myocardium, TMYX stimulated myocardial PI3K activities and PI3K (Tyr458) phosphorylation and enhanced Akt activities and Akt phosphorylation at Tyr315. TMYX increased the activities of eNOS and the phosphorylation of eNOS at Ser¹¹⁷⁷ in the NR myocardium and attenuated cardiomyocyte apoptosis by increasing the expression of Bcl-2 and decreasing that of caspase-3 and Bax. All these effects of TMYX were abolished by the specific inhibitors of PI3K (LY) and eNOS (L-NAME).

CONCLUSIONS

TMYX attenuates myocardial NR after ischemia and reperfusion by activating the PI3K/Akt/eNOS pathway and regulating apoptosis, further up-regulating NO activity and relaxing coronary microvessels.

High content screening identifies licoisoflavone A as a bioactive compound of Tongmaiyangxin Pills to restrain cardiomyocyte hypertrophy via activating Sirt3

BACKGROUND

Cardiac hypertrophy is a prominent feature of heart remodeling, which may eventually lead to heart failure. Tongmaiyangxin (TMYX) pills are a clinically used botanical drug for treating multiple cardiovascular diseases including chronic heart failure. The aim of the current study was to identify the bioactive compounds in Tongmaiyangxin pills that attenuate cardiomyocytes hypertrophy, and to investigate the underlying mechanism of action.

METHODS AND RESULTS

The anti-hypertrophy effect of TMYX was validated in isoproterenol-induced cardiac hypertrophy model in C57BL/6 mice. After TMYX treatment for 2 weeks, the heart ejection fraction and fractional shortening of the mice model was increased by approximately 20% and 15%, respectively, (p < 0.05). Besides, TMYX dose-dependently reduced the cross section area of cardiomyocytes in the angiotensin-II induced hypertrophy H9c2 model (p < 0.01). Combining high content screening and liquid chromatography mass spectrometry, four compounds with anti-cardiac hypertrophy effects were identified from TMYX, which includes emodin, licoisoflavone A, licoricone and glyasperin A. Licoisoflavone A is one of the compounds with most significant protective effect and we continued to investigate the mechanism. Primary cultures of neonatal rat cardiomyocytes were treated with a hypertrophic agonist phenylephrine (PE) in the presence or absence of licoisoflavone A. After 48 h of treatment, cells were harvested and mitochondrial acetylation was analyzed by western blotting and Image analysis. Interestingly, the results suggested that the anti-hypertrophic effects of licoisoflavone A depend on the activation of the deacetylase Sirt3 (p < 0.01). Finally, we showed that licoisoflavone A-treatment was able to decrease relative ANF and BNP levels in the hypertrophic cardiac cells (p < 0.01), but not in cells co-treated with Sirt3 inhibitors (3-TYP) (p > 0.05).

CONCLUSION

TMYX exerts its anti-hypertrophy effect possibly through upregulating Sirt3 expression. Four compounds were identified from TMYX which may be responsible for the anti-hypertrophy effect. Among these compounds, licoisoflavone A was demonstrated to block the hypertrophic response of cardiomyocytes, which required its positive regulation on the expression of Sirt3. These results suggested that licoisoflavone A is a potential Sirt3 activator with therapeutic effect on cardiac hypertrophy.

Development of a HPLC-MS/MS Method to Determine 11 Bioactive Compounds in Tongmai Yangxin Pill and Application to a Pharmacokinetic Study in Rats

A sensitive and reliable HPLC-MS/MS method has been developed and validated for simultaneous determination of eleven bioactive compounds (rhein, emodin, stilbene glycoside, liquiritin, ononin, verbascoside, gallic acid, schisandrin, liquiritigenin, glycyrrhizic acid, and isoliquiritigenin) in rat plasma after oral administration of Tongmai Yangxin Pill. The collected plasma samples were prepared by liquid-liquid extraction with ethyl acetate after acidification. Eleven compounds were separated on a CORTECS™ C18 column with mobile phases consisting of 0.1% formic acid in deionized water and acetonitrile. The flow rate was 0.3 mL/min. The detection was performed on a tandem mass system with an electrospray ionization (ESI) source in both positive and negative ionization using multiple-reaction monitoring (MRM) mode. The calibration curves were linear over the range of 8-2000 ng/mL for glycyrrhizic acid; 4-1000 ng/mL for liquiritin; 0.8-200 ng/mL for emodin, gallic acid, ononin, schisandrin, and stilbene glycoside; 0.4-100 ng/mL for isoliquiritigenin, liquiritigenin, rhein, and verbascoside, respectively. The intra- and interday precision of the analytes were less than 9.3% and 8.5%. The intra- and interday accuracy were in the range of -14.0% to 10.3% and -6.5% to 9.6%. Meanwhile, the extraction recovery of the analytes in plasma samples ranged from 85.2% to 109.1% and matrix effect from 89.2% to 113.4%. The developed method was successfully applied to the pharmacokinetics of eleven bioactive compounds in rat plasma after oral administration of Tongmai Yangxin Pill prescription.

Establishing a Cell-Based High-Content Screening Assay for TCM Compounds with Anti-Renal Fibrosis Effects

Renal fibrosis is thought to be the final common pathway leading to chronic kidney disease (CKD) and end-stage renal failure. Except for renal replacement therapy, no adequate treatment regimen is available; therefore studies on the treatment of renal fibrosis have attracted significant interest. In recent years, studies have shown that traditional Chinese medicine (TCM) may represent an attractive source to produce drugs with antifibrosis effects. The aim of this study was to establish a robust cell-based high-content screening (HCS) approach to identify TCM compounds with antifibrosis effects in NRK49F cells following TGF-β1 exposure. When designing the model, one of the most important steps involved the stability and reproducibility of this cell-based model. Therefore, we initially optimized the experimental parameters. Then, our HCS model was validated using SB525334, an inhibitor of the TGF-β1 receptor, and curcumin and emodin, two TCM compounds with well-documented anti-renal fibrosis activity. Subsequently, the proven reliable HCS model was used to screen a standard TCM compound library, which included 344 TCM molecules. Based on our HCS algorithm, a total of 16 compounds were identified to have prospective inhibitory activity. These compounds were further validated by verification experiments. Strikingly, eight compounds have been shown to inhibit renal fibrosis; six of them had rarely been described in the literature, namely, Ligustrazine, Glycyrrhizic acid, Astragaloside iv, Hydroxysafflor Yellow A, Crocin, and Gypenosides. To the best of our knowledge, this is the first study in which a HCS assay was performed to identify TCM compounds with anti-renal fibrosis effects. The HCS approach was successfully applied to screen active compounds and will be propitious to further anti-renal fibrosis drugs discovery research. Meanwhile, it may offer possibilities for identifying lead compounds for treating other diseases from registered Chinese herbal medicines.

Monitoring and manipulating cellular crosstalk during kidney fibrosis inside a 3D in vitro co-culture

In pharmacological research the development of promising lead compounds requires a detailed understanding of the dynamics of disease progression. However, for many diseases, such as kidney fibrosis, gaining such understanding requires complex real-time, multi-dimensional analysis of diseased and healthy tissue. To allow for such studies with increased throughput we established a dextran hydrogel-based in vitro 3D co-culture as a disease model for kidney fibrosis aimed at the discovery of compounds modulating the epithelial/mesenchymal crosstalk. This platform mimics a simplified pathological renal microenvironment at the interface between tubular epithelial cells and surrounding quiescent fibroblasts. We combined this 3D technology with epithelial reporter cell lines expressing fluorescent biomarkers in order to visualize pathophysiological cell state changes resulting from toxin-mediated chemical injury. Epithelial cell damage onset was robustly detected by image-based monitoring, and injured epithelial spheroids induced myofibroblast differentiation of co-cultured quiescent human fibroblasts. The presented 3D co-culture system therefore provides a unique model system for screening of novel therapeutic molecules capable to interfere and modulate the dialogue between epithelial and mesenchymal cells.