1. Introduction
Type 2 diabetes mellitus (T2DM) is the most common form of diabetes mellitus and is a rapidly growing global problem [
1]. T2DM is associated with the diverse interplay of genetic, environmental, and behavioral risk factors [
2]. T2DM patients are often more vulnerable to a number of short- and long-term difficulties, which can result in serious complications [
3]. In 2011, 366 million individuals were expected to have diabetes; by 2030, that number will have increased to 552 million [
4]. It is proposed that the incidence of T2DM will rise in the next couple of decades, with much of the growth appearing in the developed world [
5]. Despite the fact that the etiology and pathogenesis of T2DM are unclear, insulin resistance has long been thought to be a major pathological hallmark of T2DM patients [
6,
7]. As a result, understanding the mechanisms of insulin resistance and discovering novel drugs that promote insulin sensitivity are critical in the fight against T2DM. Pharmacotherapy consisting of natural products is seen as a viable therapeutic method for T2DM and could provide answers to the questions raised above.
Abrus precatorius L. is a herbaceous plant of fabaceae, which flowers in winters. The latest pharmacological studies suggest that
A. precatorius possesses antidiabetic, antimicrobial, anticancer, and anti-inflammatory properties due to the presence of natural bioactive compounds [
8,
9]. Alkaloids, steroids, tannin, triterpenoids, protein, flavonoids, and phenolic compounds are among the secondary chemicals isolated from
A. precatorius [
8,
9,
10,
11]. The findings of this study show that
A. precatorius is a root and distinctive source of numerous promising phytochemicals, making it a valuable and adaptable plant with a wide range of therapeutic qualities.
Network pharmacology (NP) is a rising star in the field of drug discovery, as it integrates systematic medicine with information science [
12]. It is an integrative in silico approach for introducing a ‘protein-compound/disease-gene’ network in order to reveal the mechanisms underlying the synergistic therapeutic actions of traditional medicines [
13]. This advancement, in turn, has shifted the paradigm from a ‘one-target, one-drug’ mode to a ‘network-target, multiple-component-therapeutics’ mode.
The use of bioactive compounds to reform medicines in the future is exciting, and prospects for curing multiple diseases are encouraging. Recently, Li et al. [
14] employed a network pharmacology-based approach to explore the active ingredients of Ge-Gen-Qin-Lian decoction for the treatment of T2DM. Hence, network pharmacology provided a powerful means for identifying bioactive ingredients and mechanisms of action for Traditional Chinese medicinal (TCM) herbs/herbal formulae for the treatment of disease and disorders [
15]. In this current work, a comprehensive NP-based approach was used to explore the active ingredients of
A. precatorius. To the best of our knowledge, this is the first study that integrated bioinformatics analysis with NP to explore the mechanism of
A. precatorius for T2DM treatment. This study gives a new and novel insight in terms of understanding the molecular mechanism of the anti-diabetic activity of
A. precatorius and expedites the process of drug discovery. Moreover, this breakthrough has sparked a new interest in the search for candidate drugs from
A. precatorius. In the framework of this study, bioactive compounds of
A. precatorius, as well as the putative mechanism underlying its anti-T2DM effect, were analyzed by employing a network pharmacology approach along with molecular-docking analysis. Moreover, laboratory experiments are recommended to explore the substance’s pharmacological potential in the near future.
3. Discussion
Type 2 diabetes mellitus is a multifactorial chronic metabolic condition characterized by relative insulin deficiency, hyperglycemia, and insulin resistance [
21]. All around the globe, the rate of patients with diabetes mellitus has reached an unimaginable level, and 80 percent of those with the disease reside in low- and middle-income countries [
22]. Metformin, Repaglinide, Sitagliptin, Glimepiride, Pioglitazone, Sitagliptin, and Acarbose [
23] are generally prescribed for T2DM patients, but all these oral anti-diabetic medicines have been linked to major side effects. As a result, the search for new medications has grown more focused. In this context, a high-potency source of phytoconstituents with health advantages could be a promising T2DM treatment candidate.
Medicinal plants are considered a natural pool and an infinite source of medicinal agents due to the presence of naturally occurring compounds [
24,
25]. Natural products and their derivatives make up nearly half of all clinically used pharmaceuticals, and due to their structural variety, multi-target action, and low toxic side effects, they have been a hot topic in recent years as a research trend and possible source for targeted drugs. Over the past dozen years, high-throughput techniques have proposed a strong arm in screening the pharmacological efficacy of herbal medicines in drug discovery [
26,
27]. The discovery of potentially bioactive compounds that cease the pathophysiology of disorders and diseases will be considered a thunderbolt of this present epoch.
A. precatorius is a medicinal herb abundantly found across Afro-Asian regions of the world. This plant has therapeutic properties used to treat a variety of ailments. Various parts of the plant, such as seeds, roots, and leaves, are utilized for a variety of medical purposes. Flavonoids, glycosides, triterpenoids, abrin, and alkaloids are the main components of
A. precatorius [
8,
28,
29]. The conventional usage of
A. precatorius in the treatment and management of diabetes mellitus has been emphasized in various reports [
30,
31]. Of note, compounds of
A. precatorius revealed efficacy in treating breast cancer [
32] and diabetes mellitus [
33]. This study is a touchstone for the initial screening of bioactive compounds of
A. precatorius as well as a new therapeutic concept for further exploration on mechanisms of
A. precatorius for T2DM treatment. In our line of work, screening results represented that triterpenoids, flavonoids, steroids, and alkaloids were the main bioactive compound of
A. precatorius, which played a decisive role in the development of T2DM by affecting AKT1, MAPK3, TNFalpha, and MAPK1 genes. Furthermore, molecular docking also confirmed our findings that stable binding forces exist between core compounds and key targets. By constructing a model of ‘herb-active compounds–targets–pathways’, we discovered that abrectorin, abrusin, abrisapogenol J, sophoradiol, cholanoic acid, precatorine, and cycloartenol had a strong association in the network, indicating that it has anti-diabetic properties. Moreover, molecular docking also strengthened our findings by successfully validating the interaction that exists between highly active constituents and their putative targets. Finally, the associated ADMET properties of potential compounds for different models, such as P-glycoprotein substrates, BBB penetration, and gastrointestinal absorption, showed positive results that strongly support the compounds’ suitability as drug candidates.
According to GO functional analysis, the anti-diabetic targets of A. precatorius were mainly involved in insulin receptor substrate binding, protein autophosphorylation, insulin receptor substrate binding, and the regulation of insulin secretion. KEGG pathway studies revealed that targets were concentrated in diabetes-related pathways. In addition to being enriched in diabetes-related pathways, anti-diabetic targets were also involved in other pathways that are intimately tied with T2DM, such as neuroactive ligand–receptor interaction, the AMPK signaling pathway, the PI3K-Akt signaling pathway, and pathways in cancer.
In the current analysis, we discovered many target genes participating in various metabolic pathways. By targeting the genes that cause disturbance in metabolic pathways, the pathophysiology of disease can be halted. A few of studies strengthened our findings, such as one that showed that most people suffering from T2DM are insulin resistant just because of glucose toxicity [
34]. It is noteworthy that two of our key targets, namely, AKT1 and MAPK1, are mainly involved in insulin-resistant pathways. AKT1 or Akt serine/threonine kinase 1 regulates glucose metabolism [
35]. This gives clear evidence to the concept that the dysregulation of AKT1 signaling pathways may be affiliated with an increased risk of T2DM. In the wake of the worldwide increase in T2DM, the central theme of research is to better understand the signaling pathways affecting this disease. Our analysis proposed that AKT1, MAPK1, and MAPK3 are directly involved in insulin signaling pathways. Hence, variation in these genes may cause disturbance in the associated pathways, which in turn leads to a disease state. Beyond this, the targeted genes of active constituents are also enriched in various inflammatory conditions such as rheumatoid arthritis, which seems to indicate that it can act on various anti-inflammatory cytokines and exert an effect on T2DM.
According to the ‘compounds–targets network’, we screened seven compounds and four genes for a docking experiment. Furthermore, docking results verified our findings and showed that abrisapogenol J, abrusin, cycloartenol, and precatorine bind stably with the active pockets of target genes, which spotlight that these compounds can be considered for the treatment of T2DM by inhibiting AKT1, MAPK3, TNFalpha, and MAPK1 genes. In the light of network pharmacology, the current study elaborates on the active compounds, their potential targets, and associated pathways to treat T2DM, hence providing a theoretical basis for additional experimental research. Bearing in mind the limitations of network pharmacology, the basic pharmacological mechanisms for the treatment of T2DM is only achieved by mining data. Network pharmacology presently relies on different databases for bioactive mining. Databases, though curated, may show discrepancies due to numerous sources of information and experimental data. A way to navigate around this problem is to make use of modern, high-throughput chemical identification techniques such as ultra-performance liquid chromatography–electrospray mass spectroscopy [
36]. Despite the fact that we have presented some interesting data, additional studies and clinical trials are needed to explore the potential of
A. precatorius to validate their medicinal usages.