1. Introduction
Myocardial infarction (MI) results from arterial plaque accumulation leading to reductions in blood flow, reduced oxygen and damage to the heart muscles [
1,
2,
3]. MI symptoms include chest pain, heartbeat abnormalities, shortness of breath and nausea, amongst others [
2,
4]. If these symptoms are not treated rapidly, MI can lead to death [
5,
6]. It is thus important to prevent and alleviate the symptoms of MI to save patients’ lives.
Traditional Chinese medicine (TCM) has been used for many thousands of years in China [
7]. The Gualou Xiebai Banxia decoction is an herbal formula that was first described in the “Synopsis of the Golden Chamber” by Zhang Zhongjing in the Eastern Han Dynasty [
8]. It is composed mostly of Gualou, Xiebai and Banxia [
9]. For centuries, Gualou and Xiebai have been used for the clinical treatment of cardiovascular diseases (CVDs), including MI, heart failure and arrhythmia [
10,
11]. Extracts of Gualou (
Trichosanthes kirilowii Maxim) and Xiebai (
Allium macrostemon Bge) have been found to improve cardiac function and hemodynamics and have been shown to be effective in treating ischemia/reperfusion injuries and MI [
12,
13,
14]. Banxia (
Pinellia pinellia), likewise, has significant therapeutic actions in CVD [
14]. The Gualou Xiebai Banxia decoction is a commonly prescribed TCM for the treatment of CVD, including MI [
15]. Furthermore, Gualou Xiebai Banxia decoction has been found to protect against type II diabetes (T2DM) treatment with acute myocardial ischemia (AMI) (T2DM-AMI) by attenuating oxidative stress (OS) and apoptosis via phosphatidyl inositol 3-kinase (PI3K)/serine/threonine protein kinase B (Akt)/endothelial nitric oxide synthase (e-NOS) signaling [
15]. Specifically, Gualou Xiebai Banxia decoction is reported to upregulate PI3K, Akt and e-NOS mRNA and protein in T2DM-AMI rats, leading to protection against T2DM-AMI [
15]. Although the Gualou Xiebai Banxia decoction has been demonstrated to have a specific protective effect against MI, its mechanism of action and the pathways involved still require further study.
Network pharmacology was introduced by Hopkins in 2007 [
16,
17] and predicts drug–target interactions based on the structures of the interacting molecules and the effectiveness of the drug’s action. This approach takes into account the multiple interactions occurring within the body and constructs a network between the drug, the molecular target and the disease, together with an analysis of the genes associated with the disease [
18]. An understanding of the signaling and regulatory pathways involved in drug action can both improve the efficacy of the drug and reduce its side effects, thus ultimately improving the success of clinical trials and saving costs [
19]. Network pharmacology uses multiple levels of analysis, including omics datasets and in silico simulations, to analyze the mechanisms underlying drug effects. It is, thus, an ideal approach for analyzing the complexities of TCM [
20]. It is worth mentioning the relevance of molecular docking to drug research as it simulates the recognition process between molecules and predicts both the binding mode and the strength of the interaction between molecules and receptors through a scoring function. In recent years, molecular docking has contributed significantly to the field of computer-aided medical research.
Here, we used network pharmacology to explore the main components and molecular biological mechanisms of Gualou Xiebai Banxia decoction for the treatment of MI. Molecular docking was then used to verify the predicted interactions between the identified active components of Gualou Xiebai Banxia decoction and their molecular targets. The combination of molecular docking and network pharmacology provides a means of effectiveness for studying the action of Gualou Xiebai Banxia decoction, as well as a reference for follow-up research.
Figure 1 shows a flow chart of the study.
4. Discussion
Network pharmacology utilizes resemblances between the structures and the documented effects of known drugs and ligands to construct a network of interactions between ligands and targets [
33]. This method takes crosstalk between signaling pathways into account, allowing the prediction of multiple interactions that may be used in rational drug design [
34,
35,
36].
Here, we investigated the mechanism of Gualou Xiebai Banxia decoction in treating MI using various techniques, including network pharmacology, pathways analysis and molecular docking between the identified active components and predicted targets. The analysis identified 97 potential target proteins, with PPI network analysis narrowing these down to seven final targets, specifically, HIF1A, MYC, MAPK3, MAPK1, TP53, ESR1 and RELA. Molecular docking (
Figure 8) showed that four active components of the decoction, namely, baicalein, quercetin, naringenin and coniferin, can interact directly with these target proteins. Many studies have demonstrated interactions between these active compounds and their targets [
37,
38,
39]. For example, Chao et al. demonstrated that baicalein protects against retinal ischemia through anti-apoptotic effects, as well as through the downregulation of HIF-1α, vascular endothelial growth factor (VEGF) and MMP-9 and upregulation of HO-1 [
36]. Our study illustrates that quercetin also interacts with the targets identified here.
GO analysis calculates the hypergeometric distribution relationship to a particular branch of the GO classification, based on the common genes. This analysis is helpful in identifying protein functions and in pharmacological studies [
39]. GO annotates genes according to function, while KEGG analysis considers the physiological pathways [
40]. The integration of these two procedures allows the identification of specific genes and pathways [
41]. KEGG enrichment analysis indicated that the HIF-related pathway, inflammation-related pathways and PI3K/AKT-related pathways may be involved in the treatment of MI by Gualou Xiebai Banxia decoction. Interestingly, RELA, which forms part of the NF-κB pathway, also regulates the inflammatory pathway. In addition, from
Figure 8, we can see that the PI3K/AKT pathway indirectly interacts with TP53 and affects the expression of TP53. The MAPK pathway is related to MYC and ESR proteins, while the VEGF signaling identified by KEGG may affect the MAPK pathway [
42]. Through the analysis of GO and KEGG, we found that HIF1A, MYC, MAPK, TP53, ESR and RELA were likely targets of the Gualou Xiebai Banxia decoction in treating MI. Importantly, the GO, KEGG and PPI analyses all showed that HIF1A was the most significant of the identified target proteins, suggesting its importance in the action of the Gualou Xiebai Banxia decoction in the prevention or treatment of MI. However, to date, there have been no studies investigating the effects of Gualou Xiebai Banxia decoction on HIF1A, suggesting the usefulness of further investigation of this protein as a novel target of Gualou Xiebai Banxia decoction in cell and animal experiments. In addition, ESR, as one of the main targets, provides a new direction for the study of the mechanism of Gualou Xiebai Banxia decoction. It is worth noting that we have not focused on any sub-datasets for KEGG enrichment analysis, as our previous results have been screened for seven important targets, which we focus on most in our current analysis. However, KEGG results can be used as a reference for further study to demonstrate that these targets or other targets are critical and involved in MI process.
The main purpose of this research was to use network pharmacology prediction and a molecular docking-based strategy to explore the potential mechanism of Gualou Xiebai Banxia decoction in the treatment and prevention of MI. The combination of molecular docking and network pharmacology provides an effective means of studying the effects of Gualou Xiebai Banxia decoction to provide a reference for follow-up research. However, there are some limitations to the present study. It would be worthwhile to conduct additional animal or clinical experiments to verify the results. Issues such as the TCM dosage, safety and its effects after administration also require further investigation.
In this paper, we used AutoDock Vina for molecular docking, which has a relatively high average accuracy of binding mode prediction and easy operation. It successfully simulates the binding of large-molecule proteins and small-molecule ligands. We focused on network pharmacology combined with molecular docking. Network pharmacology emphasizes holistic systems and biological networks when analyzing the laws of molecular association between drugs and therapeutic targets. By focusing on drug research, it allows for an analysis of the complexity of TCM formulations, together with an explanation of the overall mechanisms of action and the provision of new scientific and technological support for drug development. With the increasing influence and applications of the big data era, network pharmacology faces both significant development opportunities and challenges [
43]. There are still many problems in current network pharmacology research, such as uneven study quality, a lack of standardized data and insufficient scientific validation. Moreover, some of the predicted targets and pathways may have undesirable effects on the drug safety, such as dizziness, headache and nitrate-related tolerance [
44]. Therefore, the optimal dose and duration of the compound require further investigation before clinical application. Thus, the establishment of rigorous, scientific and uniform criteria for the evaluation of network pharmacology is urgently needed for the further development of network pharmacology research [
43].
To summarize, Gualou Xiebai Banxia decoction contains many active components that interact with specific targets to influence downstream pathways, leading to the treatment of MI. The results showed that baicalein, quercetin, naringenin and coniferin were the key active compounds in Gualou Xiebai Banxia decoction and suggested that they may play significant roles in MI treatment. In addition, HIF1A, MYC, MAPK3, MAPK1, TP53, ESR1 and RELA were identified as key target proteins and, of these, HIF1A was the most significant. This article is the first to systematically explore the possible targets and mechanisms of Gualou Xiebai Banxia decoction in the treatment of MI. It provides a new theoretical basis for exploring therapeutic drugs and their mechanisms for the treatment of MI. However, the precise roles and mechanisms of action of the active components of Gualou Xiebai Banxia decoction in the treatment of MI have not been fully explained and verified, suggesting directions for future research.