Tongxinluo inhibits cyclooxygenase-2, inducible nitric oxide synthase, hypoxia-inducible factor-2α/vascular endothelial growth factor to antagonize injury in hypoxia-stimulated cardiac microvascular endothelial cells

Chinese patent medicine Tongxinluo: A review on chemical constituents, pharmacological activities, quality control, and clinical applications

BACKGROUND

Cardiovascular and cerebrovascular disease (CCVD) is the leading cause of morbidity and mortality worldwide, imposing a significant economic burden on individuals and societies. For the past few years, Traditional Chinese Medicine (TCM) has attracted much attention due to its advantages such as fewer side effects in the treatment of CCVD. TXL has shown great promise in the treatment of CCVD.

PURPOSE

This paper aims to provide a comprehensive introduction to TXL, covering its chemical constituents, quality control, pharmacological properties, adverse reactions, and clinical applications through an extensive search of relevant electronic databases while discussing its current challenges and provides opinions for future study.

METHODS

The following electronic databases were searched up to 2023: "TXL", "CCVD", "Chemical constituents", "Quality control" and "Pharmacological properties" were entered as keywords in PubMed, Web of Science, Google Scholar and China National Knowledge Infrastructure Database and WANFANG DATA databases. The PRISMA guidelines were followed in this review process.

RESULTS

Studies have confirmed that TXL is effective in treating patients with CCVD and has fewer adverse effects. The aim of this review is to explore TXL anti-CCVD effects in relation to oxidative stress, lipid metabolism and enhanced cardiac function. This review also provides additional information on safety issues.

CONCLUSION

TXL plays a key role in the treatment of CCVD by regulating various pathways such as lipid metabolism, oxidative stress and inflammation. However, further clinical trials and animal experiments are needed to provide more evidence and recommendations for its clinical application. This article provides an overview of TXL research to inform and inspire future studies.

Tongxinluo capsule as a multi-functional traditional Chinese medicine in treating cardiovascular disease: A review of components, pharmacological mechanisms, and clinical applications

Cardiovascular diseases (CVDs) are one of the most significant diseases that pose a threat to human health. The innovative traditional Chinese medicine Tongxinluo Capsule, developed under the guidance of the theory of traditional Chinese medicine, has good clinical efficacy in various cardiovascular diseases, this medicine has effects such as blood protection, vascular protection, myocardial protection, stabilizing vulnerable plaques, and vasodilation. However, CVDs are a multifactorial disease, and their underlying mechanisms are not fully understood. Therefore, exploring the mechanism of action and clinical application of Tongxinluo Capsule in the treatment of various cardiovascular diseases is beneficial for exerting its therapeutic effect from multiple components, targets, and pathways. At the same time, it provides broader treatment ideas for other difficult to treat diseases in the cardiovascular event chain, and has significant theoretical and clinical significance for improving the treatment of cardiovascular diseases with traditional Chinese medicine.

Coronary microvascular dysfunction and cardiovascular disease: Pathogenesis, associations and treatment strategies

Coronary microvascular dysfunction (CMD) is a high-risk factor for a variety of cardiovascular events. Due to its complex aetiology and concealability, knowledge of the pathophysiological mechanism of CMD is still limited at present, which greatly restricts its clinical diagnosis and treatment. Studies have shown that CMD is closely related to a variety of cardiovascular diseases, can aggravate the occurrence and development of cardiovascular diseases, and is closely related to a poor prognosis in patients with cardiovascular diseases. Improving coronary microvascular remodelling and increasing myocardial perfusion might be promising strategies for the treatment of cardiovascular diseases. In this paper, the pathogenesis and functional assessment of CMD are reviewed first, along with the relationship of CMD with cardiovascular diseases. Then, the latest strategies for the treatment of CMD and cardiovascular diseases are summarized. Finally, urgent scientific problems in CMD and cardiovascular diseases are highlighted and future research directions are proposed to provide prospective insights for the prevention and treatment of CMD and cardiovascular diseases in the future.

Protective Effects and Potential Mechanism of Tongxinluo on Mice with Thromboangiitis Obliterans Induced by Sodium Laurate

OBJECTIVE

To investigate the effects of Tongxinluo (TXL) on thromboangiitis obliterans (TAO) and the underlying mechanisms.

METHODS

Ninety male C57/BL6J mice were randomly divided into 6 groups according to a random number table: the sham group, TAO model group, Compound Danshen Tablet (CDT) group, and the high-, medium-, and low-dose TXL groups. All mice except the sham group were injected with sodium laurate (0.1 mL, 5 mg/mL) in the femoral artery to establish TAO mouse model. After modeling, mice in the sham and TAO model groups were intragastrically administered 0.5% (w/v) sodium carboxymethylcellulose, mice in the CDT group were intragastrically administered 0.52 g/kg CDT, and mice in the TXL-H, TXL-M, and TXL-L groups were intragastrically administered 1.5, 0.75, and 0.38 g/kg TXL, respectively. After 4 weeks of gavage, the recovery of blood flow in the lower limbs of mice was detected by Laser Doppler Imaging. The pathological changes and thrombosis of the femoral artery were observed by morphological examination. The expressions of tumor necrosis factor α (TNF-α) and inducible nitric oxide synthase (iNOS) in the femoral artery wall were detected by HE staining. Levels of thromboxane B2 (TXB2), 6-keto-prostaglandin F1α (6-keto-PGF1α), endothelin-1 (ET-1), interleukin (IL)-1β and IL-6 were measured using enzyme-linked immunosorbent assay (ELISA). Levels of activated partial thromboplastin time (APTT), prothrombin time (PT), thrombin time (TT) and fibrinogen (FIB) were detected by a fully automated biochemical analyzer.

RESULTS

TXL promoted the restoration of blood flow in the lower limbs, reduced the area of thrombosis in the femoral artery, and alleviated the pathological changes in the femoral artery wall. Moreover, the levels of TXB2, ET-1, IL-6, IL-1β, TNF-α and iNOS were significantly lower in the TXL groups compared with the model group (P<0.05 or P<0.01), while the level of 6-keto-PGF1α was significantly higher (P<0.01). In addition, APTT, PT, and TT were significantly prolonged in TXL groups compared with the model group (P<0.05 or P<0.01), and FIB levels were significantly decreased compared with the model group (P<0.01).

CONCLUSIONS

TXL had a protective effect on TAO mice, and the mechanism may involve inhibition of thrombosis and inflammatory responses. TXL may be a potential drug for the treatment of TAO.

Molecular basis of acute coronary syndrome

Cardiovascular diseases (CVD) comprise of various heart and blood vessels-related diseases. Acute coronary syndrome (ACS) is one of them. Basic researchers and cardiologists have witnessed landmark developments related to ACS and despite rapid refinement in our understanding; scientists are seeking answers for more questions. Scientists have mapped wide ranging proteins and intricate protein networks which play central role in the pathogenesis in ACS. In this review, we have attempted to summarize underlying causes of ACS. Better understanding of the disease pathology will enable us to get a step closer to an effective clinical management.

Vitamin D stimulates miR-26b-5p to inhibit placental COX-2 expression in preeclampsia

Vitamin D insufficiency or deficiency during pregnancy has been associated with an increased risk of preeclampsia. Increased placental cyclooxygenase-2 (COX-2) activity was proposed to contribute to the inflammatory response in preeclampsia. This study was to investigate if vitamin D can benefit preeclampsia by inhibiting placental COX-2 expression. Placenta tissues were obtained from 40 pregnant women (23 normotensive and 17 preeclampsia). miR-26b-5p expression was assessed by quantitative PCR. Vitamin D receptor (VDR) expression and COX-2 expression were determined by immunostaining and Western blot. HTR-8/SVneo trophoblastic cells were cultured in vitro to test anti-inflammatory effects of vitamin D in placental trophoblasts treated with oxidative stress inducer CoCl₂. 1,25(OH)₂D₃ was used as bioactive vitamin D. Our results showed that reduced VDR and miR-26b-5p expression, but increased COX-2 expression, was observed in the placentas from women with preeclampsia compared to those from normotensive pregnant women. Transient overexpression of miR-26b-5p attenuated the upregulation of COX-2 expression and prostaglandin E₂ (PGE₂) production induced by CoCl₂ in placental trophoblasts. 1,25(OH)₂D₃ treatment inhibited CoCl₂-induced upregulation of COX-2 in placental trophoblasts. Moreover, miR-26b-5p expression were significantly upregulated in cells treated with 1,25(OH)₂D₃, but not in cells transfected with VDR siRNA. Conclusively, downregulation of VDR and miR-26b-5p expression was associated with upregulation of COX-2 expression in the placentas from women with preeclampsia. 1,25(OH)₂D₃ could promote miR-26b-5p expression which in turn inhibited COX-2 expression and PGE₂ formation in placental trophoblasts. The finding of anti-inflammatory property by vitamin D through promotion of VDR/miR-26b-5p expression provides significant evidence that downregulation of vitamin D/VDR signaling could contribute to increased inflammatory response in preeclampsia.

HIF-1α is a Potential Molecular Target for Herbal Medicine to Treat Diseases

HIF-1α is an important factor regulating oxygen balance in mammals, and its expression is closely related to various physiological and pathological conditions of the body. Because HIF-1α plays an important role in the occurrence and development of cancer and other diseases, it has become an enduring research hotspot. At the same time, natural medicines and traditional Chinese medicine compounds have amazing curative effects in various diseases related to HIF-1 subtype due to their unique pharmacological effects and more effective ingredients. Therefore, in this article, we first outline the structure of HIF-1α and the regulation related to its expression, then introduce various diseases closely related to HIF-1α, and finally focus on the regulation of natural medicines and compound Chinese medicines through various pathways. This will help us understand HIF-1α systematically, and use HIF-1α as a target to discover more natural medicines and traditional Chinese medicines that can treat related diseases.

A Multicenter, Randomized, Double-Blind, and Placebo-Controlled Study of the Effects of Tongxinluo Capsules in Acute Coronary Syndrome Patients with High On-Treatment Platelet Reactivity

Background

High platelet reactivity (HPR) during clopidogrel treatment predicts postpercutaneous coronary intervention (PCI) ischemic events strongly and independently. Tongxinluo capsules (TCs) are a traditional Chinese medicine formulation used as antiplatelet treatment. However, its efficacy against HPR is not known. The aim of the present study was to evaluate the effects of TCs in acute coronary syndrome (ACS) patients with HPR.

Methods

This multicenter, randomized, double-blind, placebo-controlled study prospectively analyzed 136 ACS patients with HPR who underwent PCI. The patients were enrolled from November 2013 to May 2014 and randomized to receive placebo or TCs in addition to standard dual antiplatelet therapy (DAPT) with aspirin and clopidogrel. The primary end points were the prevalence of HPR at 30 days and the mean change in P2Y₁₂reaction units (PRUs) between baseline and 30 days. Survival curves were constructed with Kaplan-Meier estimates and compared by log-rank tests between the two groups.

Results

Both groups had a significantly reduced prevalence of HPR at 30 days versus baseline, but the TC group, compared with the placebo group, had greater reduction (15.8% vs. 24.8%, P = 0.013), especially among patients with one cytochrome P450 2C19 loss of function (LOF) allele (χ² = 2.931, P = 0.047). The TC group also had a lower prevalence of HPR (33.3% vs. 54.2%, t = 5.284, P = 0.022) and superior performance in light transmittance aggregometry and higher levels of high-sensitivity C-reactive protein (hsCRP), but the composite prevalence of ischemic events did not differ significantly (χ² = 1.587, P = 0.208).

Conclusions

In addition to standard DAPT with aspirin and clopidogrel, TCs further reduce PRU and hsCRP levels, especially in patients carrying only one LOF allele. The data suggest that TCs could be used in combination therapy for ACS patients with HPR undergoing PCI.

Potential Effectiveness of Chinese Patent Medicine Tongxinluo Capsule for Secondary Prevention After Acute Myocardial Infarction: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background: Chinese patent medicine Tongxinluo capsule (TXL) is commonly used for cardio-cerebrovascular diseases. Previous research had demonstrated that TXL exhibited great clinical effects on the treatment of acute myocardial infarction (AMI), however there is a lack of systematic review. The purpose of this study was to evaluate the potential effectiveness and safety of TXL for secondary prevention in patients with AMI. Method: We searched 6 databases to identify relevant randomized controlled trials (RCTs) from inceptions to December 30, 2017. Two review authors independently assessed the methodological quality and analyzed data by the RevMan 5.3 software. The publication bias was assessed through funnel plot and Begg's test. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used for evaluating the quality of evidence. Results: We included 19 RCTs in this review and performed a meta-analysis based on 16 studies. There were statistical differences of TXL treatment group in reducing primary cardiovascular events (cardiac death [RR = 0.27, 95%CI: 0.08~0.95, I2 = 0%], recurrent myocardial reinfarction [RR = 0.38, 95%CI: 0.20~0.74, I2 = 0%], arrhythmia [RR = 0.44, 95%CI: 0.30~0.66, I2 = 0%], recurrent angina pectoris [RR = 0.34, 95%CI: 0.17~0.69, I2 = 0%]). TXL could improve cardiac function (LVEF [MD = 4.10, 95%CI: 3.95~4.25, I2 = 0%]), regulate blood lipid TC [MD = -0.66, 95%CI: -0.94 ~ -0.37, I2 = 74%], TG [MD = -0.38, 95%CI: -0.62 ~ -0.14, I2 = 70%], LDL-C[-0.40, 95%CI: -0.65 ~ -0.16, I2 = 88%), decrease the level of hs-CRP (4-week: MD = -0.78, 95%CI: -0.97 ~ -0.60, I2 = 20%; Over 4-week: MD = -1.36, 95%CI: -1.55 ~ -1.17, I2 = 20%). However, TXL has little effects on revascularization [RR = 0.45, 95%CI: 0.13~1.56, I2 = 0%], recurrent heart failure (RR = 0.83, 95%CI: 0.27~2.57, I2 = 0%), and HDL-C (MD = 0.14, 95%CI: 0.00 ~0.29, I2 = 73%). Furthermore, TXL treatment group was more prone to suffer gastrointestinal discomfort. Conclusion: Chinese patent medicine TXL seemed beneficial for secondary prevention after AMI. This potential benefit needs to be further assessed through more rigorous RCTs. Systematic review registration number in the PROSPERO register: CRD42017068417.

Tongxinluo Reverses the Hypoxia-suppressed Claudin-9 in Cardiac Microvascular Endothelial Cells

Background:

Claudin-5, claudin-9, and claudin-11 are expressed in endothelial cells to constitute tight junctions, and their deficiency may lead to hyperpermeability, which is the initiating process and pathological basis of cardiovascular disease. Although tongxinluo (TXL) has satisfactory antianginal effects, whether and how it modulates claudin-5, claudin-9, and claudin-11 in hypoxia-stimulated human cardiac microvascular endothelial cells (HCMECs) have not been reported.

Methods:

In this study, HCMECs were stimulated with CoCl₂ to mimic hypoxia and treated with TXL. First, the messenger RNA (mRNA) expression of claudin-5, claudin-9, and claudin-11 was confirmed. Then, the protein content and distribution of claudin-9, as well as cell morphological changes were evaluated after TXL treatment. Furthermore, the distribution and content histone H3K9 acetylation (H3K9ac) in the claudin-9 gene promoter, which guarantees transcriptional activation, were examined to explore the underlying mechanism, by which TXL up-regulates claudin-9 in hypoxia-stimulated HCMECs.

Results:

We found that hypoxia-suppressed claudin-9 gene expression in HCMECs (F = 7.244; P = 0.011) and the hypoxia-suppressed claudin-9 could be reversed by TXL (F = 61.911; P = 0.000), which was verified by its protein content changes (F = 29.142; P = 0.000). Moreover, high-dose TXL promoted the cytomembrane localization of claudin-9 in hypoxia-stimulated HCMECs, with attenuation of cell injury. Furthermore, high-dose TXL elevated the hypoxia-inhibited H3K9ac in the claudin-9 gene promoter (F = 37.766; P = 0.000), activating claudin-9 transcription.

Conclusions:

The results manifested that TXL reversed the hypoxia-suppressed claudin-9 by elevating H3K9ac in its gene promoter, playing protective roles in HCMECs.

High glucose decreases claudins-5 and -11 in cardiac microvascular endothelial cells: Antagonistic effects of tongxinluo

Purpose/aim of the study: Claudins-5, -9, and -11 are tight-junction proteins that are mainly expressed in endothelial cells. Their deficiency may lead to cell barrier dysfunction, which is considered as the initiating process and pathological basis of cardiovascular disease in diabetes. We investigated whether high glucose (HG) affects claudins-5, -9, and -11 in human cardiac microvascular endothelial cells (HCMECs), and examined the effects of the traditional Chinese medication tongxinluo (TXL) on these tight junction proteins.

MATERIALS AND METHODS

HCMECs were exposed to HG with and without TXL treatment, and then mRNA and protein levels of claudins-5, -9, and -11 were examined. The distribution of claudins-5 and -11 was also investigated. Histone H3K9 acetylation (H3K9ac) in claudin-5 and claudin-11 gene promoters, which functions in transactivation, was measured.

RESULTS

We found that HG suppressed claudins-5 and -11 gene expression in HCMECs, and TXL reversed the HG-mediated inhibition of claudins-5 and -11 mRNA and protein expressions. Treatment with high-dose of TXL promoted cell membrane localization of claudins-5 and -11 in HG-stimulated HCMECs. Furthermore, high-dose of TXL blocked the inhibition of H3K9ac in claudin-5 and claudin-11 gene promoters caused by exposure to HG, thus activating gene transcription.

CONCLUSIONS

Our results show that HG suppressed claudins-5 and -11 in HCMECs, and TXL could reverse the HG-induced suppression of claudins-5 and -11 by increasing H3K9ac in their respective gene promoters.

The injury of fine particulate matter from cooking oil fumes on umbilical cord blood vessels in vitro

Cooking oil fumes (COFs) derived PM_2.5 is the major source of indoor air pollution in Asia. For this, a pregnant rat model within different doses of cooking oil fumes (COFs) derived PM_2.5 was established in pregnancy in our research. Our previous studies have showed that exposure to COFs-derived PM_2.5 was related to adverse pregnancy outcomes. However, the mechanisms of signaling pathways remain unknown. Therefore, this study aimed to investigate the underlying mechanisms induced by COFs-derived PM2.5 injury on umbilical cord blood vessels (UCs) in vitro. Exposure to COFs-derived PM_2.5 resulted in changing the expression of eNOS, ET-1, ETRA, and ETRB. In additions, western blot analysis indicated that the HIF-1α/iNOS/NO signaling pathway and VEGF/VEGFR1/iNOS signaling pathway were involved in UCs injury triggered by COFs-derived PM_2.5. In conclusion, our data suggested that exposure to COFs-derived PM_2.5 resulted in increasing of oxidative stress and inflammation, as well as dysfunction of UCs.

Tea polyphenols protect against ischemia/reperfusion-induced liver injury in mice through anti-oxidative and anti-apoptotic properties

Tea polyphenols (TPs), which are derived from tea extracts, are a class of chemicals containing polyphenol hydroxyls that have been observed to have strong anti-oxidative properties. Previous studies have demonstrated that TP can protect against hepatic ischemia/reperfusion (I/R) injury; however, the underlying mechanism remains unknown. In the present study, the mechanism underlying TPs protective effects against I/R-induced liver damage was investigated, focusing on its anti-oxidative and anti-apoptotic bioactivities. C57BL/6 mice were used to establish a hepatic I/R-induced injury model, and liver injury was analyzed using a biochemical assay. The results from the current study demonstrated that the serum expression levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were significantly increased in mice following hepatic I/R injury, while the ratio of hepatic glutathione (GSH)/oxidized GSH (GSSG) was reduced, indicating that liver damage had occurred. In mice that were orally administered with TP (50 mg/kg) 1 h prior to I/R-induced injury, the extent of liver injury was significantly attenuated. It was also observed that I/R injury significantly decreased the mRNA and protein expression levels of cytokine-inducible nitric oxide synthase in liver tissues, and this was also attenuated by pretreatment with TP. Furthermore, pretreatment with TP significantly attenuated the I/R-induced increase in liver cell apoptosis, and the expression level and activity of pro-apoptotic proteins in the liver, indicating that I/R-induced liver cell apoptosis is inhibited by TP. In conclusion, the results in the present study suggest that TP protects against hepatic I/R-induced injury by inhibiting I/R-induced oxidative damage and liver cell apoptosis.

Macrophages Aggravate Hypoxia-Induced Cardiac Microvascular Endothelial Cell Injury via Peroxynitrite: Protection by Tongxinluo

Activated macrophages contribute to endothelial dysfunction; however, it is unclear how peroxynitrite contributes to macrophage-mediated human cardiac microvascular endothelial cell (HCMEC) injury in hypoxia. In macrophage-HCMEC co-cultures subjected to hypoxia, there was an increase in hypoxia-inducible factor (HIF)-1α, HIF-2α, inducible nitric oxide synthase (iNOS), endothelin-converting enzyme (ECE)-1 and cyclooxygenase-2 (COX-2), and concomitant decrease in prostacyclin synthase (PGIS). This was mimicked by a peroxynitrite donor and attenuated by its decomposition catalyst. Tongxinluo (TXL) could decrease HIF-2α, iNOS, ECE-1 and COX-2 and increase PGIS in a dose-dependent manner, with increase of vascular endothelial growth factor. The protein alterations verified the remarkably affected mRNAs, indicating that the effects of TXL were similar to but better than that of peroxynitrite decomposition catalyst. Furthermore, TXL inhibited macrophage-mediated nitrotyrosine accumulation and attenuated HCMEC injury. The results suggest that peroxynitrite contributes to macrophage-mediated HCMEC injury in hypoxia, and TXL attenuates HCMEC injury mainly by inhibiting peroxynitrite.