Muhammad Sulaiman Zubair

Neuroblastoma is characterized by noticeable resistance to chemotherapy, largely driven by the ability of tumour cells to reorganize stress-adaptive signalling networks rather than relying on single oncogenic drivers. We conducted a study to investigate the pharmacological mode of action of doxorubicin in modifying adaptive signalling pathways in SH-SY5Y neuroblastoma cells, and whether the capacity of plant metabolites can exploit emergent biochemical vulnerabilities. Transcriptomic profiling through RNA sequencing conducted 48 h post-doxorubicin exposure unveiled the organized disruption of pathways linked with amyloidogenic processes, oncogenic signalling pathways, oxidative stress, and DNA repair. The protein–protein interactions, coupled with Kyoto Encyclopedia of Genes and Genomes pathway evaluations, revealed five network-central-hubs: BRAF, GSK3β, PARP1, BACE1, and MAOB. Structural docking integrated with 200 ns molecular dynamics simulations illustrated binding stability across multiple targets driven by three metabolites, Lactol binding to BRAF (−54.13 kcal/mol) and MAOB (−39.08 kcal/mol), Amino(1H-indol-2-yl)acetic acid to BACE1 (−41.07 kcal/mol) and GSK3β (−47.38 kcal/mol), and Quercetin-3-(6″-malonyl-glucoside) binding to PARP1 (−46.03 kcal/mol). In vitro Cell Counting Kit-8 proliferation assays validated the significant anti-neuroblastoma efficacy, with the lowest IC₅₀ (0.2397 µM) being exhibited by Amino(1H-indol-2-yl)acetic acid, followed by Lactol (1.226 µM) and Quercetin-3-(6″-malonyl-glucoside) (1.301 µM), which mirrored the cytotoxic action of doxorubicin (1.306 µM). These results suggest that plant-derived metabolites may interact with stress-adaptive signalling pathways connected with neuroblastoma. However, direct experimental validation of target engagement and pathway modulation will be required to confirm these predicted interactions.

The SARS-CoV-2 papain-like protease (PL^pro) is an essential viral enzyme that promotes viral polyprotein processing while simultaneously suppressing the host innate immune response, which makes it a primary target for developing antiviral drugs. The present study employs a comprehensive approach integrating untargeted metabolomic profiling, in silico molecular docking and dynamics simulations, Molecular Mechanics Generalized Born Surface Area (MM-GBSA) energetic assessments, and biochemical enzyme assays. This integrated method aims to discover natural PL^pro inhibitors from two ethnomedicinal plants, Lippia javanica and Acorus calamus, which have long been utilized in African traditional medicine to treat respiratory diseases. Comprehensive metabolite profiling using untargeted Ultra-Performance Liquid Chromatography–Tandem Mass Spectrometry (UPLC-MS/MS) and Global Natural Products Social (GNPS) molecular networking revealed flavonoid glucuronides and phenylpropanoid derivatives as the major constituents in both plant species. In situ histochemical staining further offered spatial validation of phenolic- and lignin-associated tissues, supporting the phenolic-dominated molecular families detected by GNPS molecular networking. In silico evaluation of six selected compounds demonstrated spontaneous and thermodynamically favorable binding to PL^pro, with ΔG_bind values ranging from −5.63 to −6.43 kcal/mol. Catechin-7-glucoside emerged as the lead compound, establishing multiple hydrogen bond networks with Asp164, Gln269, Tyr264, and Asn267, supplemented by hydrophobic engagement with Pro247 and Pro248, and π-π stacking with the blocking loop 2 (BL2 loop). Molecular dynamics simulations confirmed the stability of the protein–ligand complexes. Biochemical enzyme assays confirmed concentration-dependent inhibition of PL^pro proteolytic and deubiquitinating activity by both crude plant extracts and isolated bioactive compounds. However, S-adenosyl-methionine showed comparatively high PL^pro proteolytic activity (IC₅₀ 5.872 µM) compared to catechin-7-glucoside, with an IC₅₀ of 7.493 µM, exhibiting efficacy similar to the reference inhibitor GRL0617. Both the extracts of L. javanica and A. calamus have shown significant inhibitory activity while maintaining cell viability in Human embryonic kidney 293T cell (HEK293T) culture models, indicating a favorable safety profile of the tested concentrations. Based on these results, catechin-based polyphenols and phenylpropanoid derivatives appear as promising lead compounds for the development of PL^pro inhibitors. To progress toward therapeutic use, further work is necessary in pharmacokinetics, structural optimization, and antiviral validation in cell models.

Despite growing interest in South African medicinal plants, advanced metabolomic workflows that integrate positive (ESI+) and negative (ESI−) ionization modes in UPLC-MS/MS remain sparsely applied to South African flora, and especially to Acorus calamus and Lippia javanica species. Herein, application of a dual-polarity (positive (ESI+) and negative (ESI−) ionization modes) using an untargeted UPLC–MS/MS workflow, integrated with HEK293T cytotoxicity screening, to map their metabolomes, and rank potential signature metabolites for targeted antiviral follow-up. SwissADME supported in silico drug-likeness. Neither plant extract was cytotoxic across the concentration range, with absorbance-based cell viability of 73.82% for L. javanica and 77.23% for A. calamus at 250 µg/mL, and fluorescence-based cell viability ≥59.87% and ≥55.89%, respectively. Dual-polarity expanded coverage with ESI− yielded 312 features, compared with 225 with ESI+, consistent with the predominance of acidic phenolics in plant species. Unsupervised and supervised models segregated the plant species (PCA PC1/PC2 variance: ESI+ 89.4%/3.0%; ESI− 93.5%/1.8%; R²X(cum) = 0.799). Differential analysis identified 118 significant features in ESI+ with 80 up-regulated, 38 down-regulated, and 139 in ESI− with 96 up-regulated, 43 down-regulated. The ESI− showed the wider dynamic range. Chemotypes enriched among significant metabolites include flavonols of 3-O-methylkaempferol, apigenin, and conjugates of Pollenin A, iridoid glycosides of oleoside, forsythoside B, and jasmonate-pathway oxylipins of 7-epi-12-hydroxyjasmonic acid and its glucoside. These also include caryoptosidic acid and catechin-7-glucoside, which are ionized in both modes, pinning the increase in biomarker robustness. In conclusion, a dual-mode UPLC–MS/MS approach, integrated with cytotoxicity exploration, delivers a complementary metabolome coverage and a safety awareness for shortlisting of potential signature metabolites from L. javanica and A. calamus. Moreover, in vitro inhibition of SARS-CoV-2 papain-like protease (PL^pro) by these plants links chemical signatures to antiviral relevance. Shortlisted significant metabolites that demonstrated favorable drug-likeness include flavonol scaffolds of 3-O-methylkaempferol, Pollenin A, and jasmonate-pathway derivatives of 7-epi-12-hydroxyjasmonic acid. Moreover, the dual ionization mode may eliminate ionization bias, broaden metabolome coverage, and yield a mechanism-ready shortlist of metabolites from South African medicinal plants for downstream antiviral investigation.

Purpose: To investigate the activity of self-nanoemulsifying drug delivery system (SNEDDS) containing B. medicinalis and M. oleifera ethanolic extracts. Method: The SNEDDS was prepared using propylene glycol (40 %), Tween 80 (50 %), and isopropyl myristate (10 %). Transmittance percentage, particle size, polydispersity index, and zeta potential were evaluated. In vitro immunostimulant activity was measured by assessing the macrophages' phagocytic capacity and proliferation of lymphocyte cells using MTT assay. In vivo immunostimulant activity was determined by measuring the number (%) of leukocytes, neutrophils, and lymphocytes in Wistar male rats over 14 days following administration of the SNEDDS after induction with Staphylococcus aureus. Results: The SNEDDS formula of combined extract of B. medicinalis and M. oleifera demonstrated polydispersity index (0.46 ± 0.00), particle size (24.4 ± 0.1 nm), zeta potential (-37.73 ± 0.32 mV) and percentage transmittance (86.81 ± 0.16 %). In vitro and in vivo tests revealed that SNEDDS significantly increased macrophage phagocytic capacity, number of leukocytes, neutrophils and lymphocytes over 14 days of treatment (p < 0.05) following induction with S. aureus. Conclusion: Self-nanoemulsifying drug delivery system of combined ethanol extract of B. medicinalis and M. oleifera demonstrates stable physicochemical properties, and increases macrophage phagocytic activity, leukocytes, neutrophils and lymphocyte count.

The expected progress in SARS-CoV-2 vaccinations, as anticipated in 2020 and 2021, has fallen short, exacerbating global disparities due to a lack of universally recognized “safe and effective” vaccines. This study focuses on extracts of South African medicinal plants, Artemisia annua and Artemisia afra, to identify metabolomic bioactive compounds inhibiting the binding of the SARS-CoV-2 spike protein to ACE2 receptors. The extracts were monitored for cytotoxicity using a resazurin cell viability assay and xCELLigence real-time cell analyzer. Chemical profiling was performed using UPLC-MS/MS, orthogonal projection to latent structures (OPLS), and evaluated using principle component analysis (PCA) models. Identified bioactive compounds were subjected to in vitro SARS-CoV-2 enzyme inhibition assay using standard methods and docked into the spike (S) glycoprotein of SARS-CoV-2 using Schrodinger^® suite followed by molecular dynamics simulation studies. Cell viability assays revealed non-toxic effects of extracts on HEK293T cells at lower concentrations. Chemical profiling identified 81 bioactive compounds, with compounds like 6″-O-acetylglycitin, 25-hydroxyvitamin D3-26,23-lactone, and sesaminol glucoside showing promising binding affinity. Molecular dynamics simulations suggested less stable binding, but in vitro studies demonstrated the ability of these compounds to interfere with SARS-CoV-2 spike protein’s binding to the human ACE2 receptor. Sesaminol glucoside emerged as the most effective inhibitor against this interaction. This study emphasizes the importance of multiplatform metabolite profiling and chemometrics to understand plant extract composition. This finding is of immense significance in terms of unravelling metabolomics bioactive compounds inhibiting the binding of the SARS-CoV-2 spike protein to ACE2 receptors and holds promise for phytotherapeutics against SARS-CoV-2.

Background: Benalu batu (Begonia medicinalis) and kelor leaves (Moringa oleifera) are empirically used as alternative therapies by people in Central Sulawesi to maintain their health. Our previous research showed that the combination of these two plant extracts possessed an immunomodulatory activity. Self-Nanoemulsifying Drug Delivery System (SNEDDS) formulation was performed to improve the extract's bioavailability, solubility and stability. Objective: This study aims to formulate and characterise SNEDDS preparations of combined ethanolic extract of B. medicinalis herbs and M. oleifera leaves and further test its stability. Method: SNEDDS formulation was started by screening for proper oil, surfactant, and co-surfactant. The formula was then optimised using a ternary phase diagram and characterisation. The stability test was performed using centrifugation, heating-cooling, and freeze-thaw cycles. Results: The optimal SNEDDS formula consists of isopropyl myristate (10%), tween 80 (50%) and propylene glycol (40%). The characterisation values obtained were: Transmittance value 83.785 ± 0.275%, particle size 18.666 ± 0.208 nm, polydispersity index 0.664 ± 0.0085, and zeta potential -39.20 ± 0.2 mV. The formula was stable during three stability evaluation tests. Conclusion: The optimal formula met the SNEDDS characteristics requirements and showed good stability.

Diabetes contributes to the rising global death rate. Despite scientific advancements in understanding and managing diabetes, no single therapeutic agent has been identified to effectively treat and prevent its progression. Consequently, the exploration for new antidiabetic therapeutics continues. This study aimed to investigate the antidiabetic bioactive ethyl acetate fraction of F. lutea at the molecular level to understand the molecular interactions and ligand-protein binding. To do this, the fraction underwent column chromatography fractionation to yield five compounds: lupeol, stigmasterol, α-amyrin acetate, epicatechin, and epiafzelechin. These compounds were evaluated in vitro through α-glucosidase inhibition and glucose utilization assays in C2C12 muscle and H-4-11-E liver cells using standard methods. In silico analysis was conducted using molecular docking and ADMET studies. Epicatechin exhibited the most potent α-glucosidase inhibition (IC₅₀ = 5.72 ± 2.7 µg/mL), while epiafzelechin stimulated superior glucose utilization in C2C12 muscle cells (33.35 ± 1.8%) and H-4-11-E liver cells (46.7 ± 1.2%) at a concentration of 250 µg/mL. The binding energies of the isolated compounds for glycogen phosphorylase (1NOI) and α-amylase (1OSE) were stronger (<−8.1) than those of the positive controls. Overall, all tested compounds exhibited characteristics indicative of their potential as antidiabetic agents; however, toxicity profiling predicted epiafzelechin and epicatechin as better alternatives. The ethyl acetate fraction and its compounds, particularly epiafzelechin, showed promise as antidiabetic agents. However, further comprehensive studies are necessary to validate these findings.

Englerophytum magalismontanum, a medicinal plant with ethnopharmacology use, has a dearth of information regarding its antidiabetic properties. This study evaluated the crude methanol leaf extract of E. magalismontanum and its fractions for total phenolic content, antioxidant activity, and digestive enzymes (α-amylase and α-glucosidase) inhibitory activity using standard methods. The total phenolic content (56.53 ± 1.94 mg GAE/g dry extract) and DPPH Trolox antioxidant equivalent (TAE) (1.51 ± 0.66 µg/mL) of the methanol fraction were the highest among the fractions. The IC₅₀ values of the methanol fraction against α-amylase (10.76 ± 1.33 µg/mL) and α-glucosidase (12.25 ± 1.05 µg/mL) activities were also high. Being the most active, the methanol fraction was subjected to bio-assay guided column chromatography-based enzyme inhibition to obtain a pure compound. The phenolic compound isolated and identified as naringenin inhibited α-amylase and α-glucosidase with IC₅₀ of 5.81 ± 2.14 µg/mL and 4.77 ± 2.99 µg/mL, respectively. This is the first study to isolate naringenin from E. magalismontanum extract. The molecular docking and molecular dynamics studies demonstrated naringenin as a promising lead compound in comparison to acarbose for the treatment of diabetes through the inhibition of α-glucosidase activity.

Hepatitis C Virus (HCV) is reported to develop GS-461203 resistance because of multiple mutations within the RNA-dependent RNA Polymerase (RdRp) of HCV. The lack of a high-resolution structure of these RdRp mutants in complex with GS-461203 hinders efforts to understand the drug resistance. Here we decipher the binding differences of GS-461203 in the wild type and mutated systems T179A or M289L of HCV RdRp Genotype 2a using homology modeling, molecular docking, and molecular dynamics simulation. Key residues responsible for GS-461203 binding were identified to be Arg48, Arg158, Asp318, Asp319, and Asp220, and that mutations T179A or M289L have caused conformational changes of GS-461203 in the RdRp active site. The affinities of GS-461203 were reduced in T179A system, but it became slightly stronger in the M289L system. Furthermore, we designed two new analogues of GS-461203 which encouragingly induced more stable interactions than GS-461203, and thus resulted in much better binding energies. This present study reveals how a single mutation, T179A or M289L, will modulate GS-461203 binding in HCV RdRp Genotype 2a, while introducing two novel analogues to overcome the drug resistance which may be good candidate for further experimental verification.