Xanthine oxidase (XO) has been well-recognized as a validated target for the treatment of hyperuricemia and gout. Currently, there are two drugs in clinical use that shut down XO overactivity, allopurinol and febuxostat; however, detrimental side effects restrict their applications. Propolis is a unique natural adhesive biomass of structurally variable and biologically active metabolites that exert remarkable health benefits. Moreover, combination drug therapy has become a promising pharmacotherapeutic strategy directed for reformulating existing drugs into new combination entities with potentiating therapeutic impacts. In this study, computer-aided molecular docking and MD simulations accompanied by biochemical testing were used for mining novel pharmacologically active chemical entities from Egyptian propolis to combat hyperuricemia. Further, with a view to decrease the potential toxicity of synthetic drugs and enhance efficacy, propolis hits were subjected to combination analysis with each of allopurinol and febuxostat. More specifically, Glide docking was utilized for a structure-based virtual screening of in-house datasets comprising various Egyptian propolis metabolites. Rosmarinic acid, luteolin, techtochrysin and isoferulic acid were the most promising virtual hits. In vitro XO inhibitory assays demonstrated the ability of these hits to significantly inhibit XO in a dose-dependent manner. Molecular docking and MD simulations revealed a cooperative binding mode between the discovered hits and standard XO inhibitors within the active site. Subsequently, the most promising hits were tested in a fixed-ratio combination setting with allopurinol and febuxostat separately to assess their combined effects on XO catalytic inhibition. The binary combination of each techtochrysin and rosmarinic acid with febuxostat displayed maximal synergy at lower effect levels. In contrast, individually, techtochrysin and rosmarinic acid with allopurinol cooperated synergistically at high dose levels. Taken together, the suggested strategy seems imperative to ensure a steady supply of new therapeutic options sourced from Egyptian propolis to regress the development of hyperuricemia.

Cancer is one of the predominant causes of death worldwide. The new trend nowadays is to exploit natural products with the hope of developing new anticancer agents with fewer side effects. Propolis is one of these natural products which showed effectiveness in cancer treatment. The aim of this study is to understand the multi-level mechanism of action of propolis constituents in cancer treatment using an integrated approach of network pharmacology-based analysis, molecular docking and in vitro cytotoxicity testing. An inhouse database of chemical constituents from Egyptian propolis was compiled and assessed for its ADME properties using the QikProp module in the Schrodinger software. STITCH, UniProt, STRING, KEGG and DAVID databases were used for construction of constituent-target gene, gene-pathway, and constituent-target gene-pathway networks with the aid of Cytoscape 3.8.2. The network pharmacology-based analysis showed that the hit propolis constituents related to cancer targets were genistein, luteolin, benzoic acid, quercetin and vanillic acid, whereas the main cancer-associated targets were CYP1A1, CYP19A1, ESR1, NOS3, CASP3 and AKT1. Twenty-four cancer-related pathways were recognized where the most enriched ones were pathways in cancer and estrogen signaling pathway. The most enriched biological processes involved in the mechanism of action of propolis constituents in cancer treatment were negative regulation of the apoptotic process and the metabolic process and negative regulation of cellular glucuronidation. Molecular docking analysis of the top hit compounds against the most enriched target proteins in the constructed networks was carried out using the Maestro interface of the Schrodinger software. Among hit compounds, quercetin and genistein exhibited the most stabilized interaction. Finally, confirmation of the potential anticancer activity of propolis was assured by in vitro cytotoxicity testing of propolis extract on human prostate cancer (DU-145), breast adenocarcinoma (MCF-7) and colorectal adenocarcinoma (Caco-2) cell lines. This study presents deeper insights about propolis molecular mechanisms of action in cancer for the first time using an integrated approach of network pharmacology, molecular docking and in vitro testing.

Most synthetic immunomodulatory medications are extremely expensive, have many disadvantages and suffer from a lot of side effects. So that, introducing immunomodulatory reagents from natural sources will have great impact on drug discovery. Therefore, this study aimed to comprehend the mechanism of the immunomodulatory activity of some natural plants via network pharmacology together with molecular docking andin vitrotesting. Apigenin, luteolin, diallyl trisulfide, silibinin and allicin had the highest percentage of C-T interactions while, AKT1, CASP3, PTGS2, NOS3, TP53 and MMP9 were found to be the most enriched genes. Moreover, the most enriched pathways were pathways in cancer, fluid shear stress and atherosclerosis, relaxin signaling pathway, IL-17 signaling pathway and FoxO signaling pathway. Additionally,Curcuma longa,Allium sativum,Oleu europea, Salvia officinalis,Glycyrrhiza glabraandSilybum marianumhad the highest number of P-C-T-P interactions. Furthermore, molecular docking analysis of the top hit compounds against the most enriched genes revealed that silibinin had the most stabilized interactions with AKT1, CASP3 and TP53, whereas luteolin and apigenin exhibited the most stabilized interactions with AKT1, PTGS2 and TP53.In vitroanti-inflammatory and cytotoxicity testing of the highest scoring plants exhibited equivalent outcomes to those of piroxicam.

The critical function of dihydroorotate dehydrogenase (DHODH) in pyrimidine synthesis attracted a great interest throughout beyond decades. Inhibitors of human DHODH (hDHODH) have validated efficacy for remedy of many immunological diseases. Brequinar and leflunomide are examples of such compounds. However, most of such immunosuppressive medications suffer from a lot of side effects and accompanied by adverse metabolic disturbances and toxicities. So that, immunomodulation utilizing natural products received the attention of many researchers. In this study, computer-aided molecular docking, molecular dynamic (MD) simulations and biochemical testing were utilized to find new pharmacologically active chemical entities from natural sources to combat immunosuppressive diseases. More specifically, Glide docking was used for a structure-based virtual screening of in-house 3D database of compounds retrieved from some traditionally known immunomodulatory plants surveyed from literature. The top five scored plants were found to be Zingiber officinale, Curcuma longa, Glycyrrhiza glabra, Allium sativum and Olea europaea. In vitro hDHODH inhibitory assays illustrated the ability of Allium sativum and silymarin standard hits; specifically, silibinin, to significantly inhibit the hDHODH enzyme. Molecular docking and MD simulations revealed a strong binding of the discovered hits within the active site. Following that, the most promising hits were tested separately with brequinar in a fixed-ratio combination setting to assess their combined effects on hDHODH catalytic inhibition. The binary combination of silibinin and brequinar revealed that in this combination, brequinar could be utilized at a dose 9.33-fold less when compared to its single-use to produce 99% inhibition for hDHODH enzyme. These findings confirmed that this binary mixture is an excellent combination providing better therapeutic effects and lower side effects.

Background: Type 2 Diabetes mellitus (DM) is an affliction impacting the quality of life of millions of people worldwide. An approach used in the management of Type 2 DM involves the use of the carbohydrate-hydrolyzing enzyme inhibitor, acarbose. Although acarbose has long been the go-to drug in this key approach, it has become apparent that its side effects negatively impact patient adherence and subsequently, therapeutic outcomes. Similar to acarbose in its mechanism of action, bee propolis, a unique natural adhesive biomass consisting of biologically active metabolites, has been found to have antidiabetic potential through its inhibition of α-amylase. To minimize the need for ultimately novel agents while simultaneously aiming to decrease the side effects of acarbose and enhance its efficacy, combination drug therapy has become a promising pharmacotherapeutic strategy and a focal point of this study. Methods: Computer-aided molecular docking and molecular dynamics (MD) simulations accompanied by in vitro testing were used to mine novel, pharmacologically active chemical entities from Egyptian propolis to combat Type 2 DM. Glide docking was utilized for a structure-based virtual screening of the largest in-house library of Egyptian propolis metabolites gathered from literature, in addition to GC–MS analysis of the propolis sample under investigation. Thereafter, combination analysis by means of fixed-ratio combinations of acarbose with propolis and the top chosen propolis-derived phytoligand was implemented. Results: Aucubin, identified for the first time in propolis worldwide and kaempferol were the most promising virtual hits. Subsequent in vitro α-amylase inhibitory assay demonstrated the ability of these hits to significantly inhibit the enzyme in a dose-dependent manner with an IC₅₀ of 2.37 ± 0.02 mM and 4.84 ± 0.14 mM, respectively. The binary combination of acarbose with each of propolis and kaempferol displayed maximal synergy at lower effect levels. Molecular docking and MD simulations revealed a cooperative binding mode between kaempferol and acarbose within the active site. Conclusion: The suggested strategy seems imperative to ensure a steady supply of new therapeutic entities sourced from Egyptian propolis to regress the development of DM. Further pharmacological in vivo investigations are required to confirm the potent antidiabetic potential of the studied combination.