Spilanthes filicaulis (Schumach. & Thonn.) C.D. Adams leaves protects against streptozotocin-induced diabetic nephropathy.

BACKGROUND AND OBJECTIVE: Diabetic neuropathy (DN) is a complex type of diabetes. The underlying cause of diabetic nephropathy remains unclear and may be due to a variety of pathological conditions resulting in kidney failure. This study examines the protective effect of the methanolic extract of Spilanthes filicaulis leaves (MESFL) in fructose-fed streptozotocin (STZ)-induced diabetic nephropathy and the associated pathway. METHODS: Twenty-five rats were equally divided randomly into five categories: Control (C), diabetic control, diabetic + metformin (100 mg/kg), diabetic + MESFL 150 mg/kg bw, and diabetic + MESFL 300 mg/kg bw. After 15 days, the rats were evaluated for fasting blood glucose (FBG), alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), urea, uric acid, serum creatinine, reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), and lipid peroxidation (MDA). Gene expression levels of cyclic adenosine monophosphate (cAMP), protein kinase A (PKA), cAMP response element-binding (CREB), cFOS and the antiapoptotic protein Bcl-2 were examined. RESULTS: We observed that MESFL at 150 and 300 mg/kg bw significantly downregulated the protein expression of cAMP, PKA, CREB, and cFOS and upregulated the Bcl-2 gene, suggesting that the nephroprotective action of MESFL is due to the suppression of the cAMP/PKA/CREB/cFOS signaling pathway. In addition, MESFL increases SOD and CAT activities and GSH levels, reduces MDA levels, and reduces renal functional indices (ALP, urea, uric acid, and creatinine). CONCLUSION: Therefore, our results indicate that MESFL alleviates the development of diabetic nephropathy via suppression of the cAMP/PKA/CREB/cFOS pathways.

Revealing innovative JAK1 and JAK3 inhibitors: a comprehensive study utilizing QSAR, 3D-Pharmacophore screening, molecular docking, molecular dynamics, and MM/GBSA analyses.

The heterocycle compounds, with their diverse functionalities, are particularly effective in inhibiting Janus kinases (JAKs). Therefore, it is crucial to identify the correlation between their complex structures and biological activities for the development of new drugs for the treatment of rheumatoid arthritis (RA) and cancer. In this study, a diverse set of 28 heterocyclic compounds selective for JAK1 and JAK3 was employed to construct quantitative structure-activity relationship (QSAR) models using multiple linear regression (MLR). Artificial neural network (ANN) models were employed in the development of QSAR models. The robustness and stability of the models were assessed through internal and external methodologies, including the domain of applicability (DoA). The molecular descriptors incorporated into the model exhibited a satisfactory correlation with the receptor-ligand complex structures of JAKs observed in X-ray crystallography, making the model interpretable and predictive. Furthermore, pharmacophore models ADRRR and ADHRR were designed for each JAK1 and JAK3, proving effective in discriminating between active compounds and decoys. Both models demonstrated good performance in identifying new compounds, with an ROC of 0.83 for the ADRRR model and an ROC of 0.75 for the ADHRR model. Using a pharmacophore model, the most promising compounds were selected based on their strong affinity compared to the most active compounds in the studied series each JAK1 and JAK3. Notably, the pharmacokinetic, physicochemical properties, and biological activities of the selected compounds (As compounds ZINC79189223 and ZINC66252348) were found to be consistent with their therapeutic effects in RA, owing to their non-toxic, cholinergic nature, absence of P-glycoprotein, high gastrointestinal absorption, and ability to penetrate the blood-brain barrier. Furthermore, ADMET properties were assessed, and molecular dynamics and MM/GBSA analysis revealed stability in these molecules.

Comparing knowledge, attitudes, and practices in cardiovascular disease prevention and health promotion between community and hospital pharmacists in Saudi Arabia: A cross-sectional study.

Purpose: Saudi Arabia is one of the leading nations in the world in terms of the high frequency of chronic diseases and their associated risk factors. Knowledge and awareness are crucial for pharmacists to play an active role in the prevention of cardiovascular diseases (CVD). The current study assessed the pharmacists' knowledge, attitude, and practice to determine the potential differences with respect to their respective practice settings toward CVD prevention and related health promotions. Methods: It is a cross-sectional study targeted the registered pharmacists in the Kingdom of Saudi Arabia. An online questionnaire was prepared, and the link was circulated through various social media platforms. Descriptive statistics, multivariate linear regression analysis and chi square test were used to analyze the data accordingly. Results: A total of 324 pharmacists were included in the study. Among these, 157 (48.4 %) were community pharmacists, and the remaining were hospital pharmacists (51.6 %). No significant differences in knowledge scores were observed between community and hospital pharmacists. The mean attitude score among community and hospital pharmacists was found to be 26.40 ± 5.125 and 25.09 ± 5.393 respectively, which was statistically significant (p = 0.026). Similarly, the total practice scores across the settings were statistically significant (p = 0.02). Gender plays a significant role in terms of knowledge scores among both community and hospital pharmacists (p = 0.016 & 0.029). Gender, professional practice experience, and number of prescriptions handled and prescriptions with CVD medications showed significant differences in the distribution of positive attitudes and good practice frequency between community and hospital pharmacists. Conclusion: It is evident that there is a deficiency in knowledge among hospital pharmacists compared to community pharmacists. Which indicates that there is a need for a rigorous continuous pharmacy education covering the fundamental aspects of CVD primary prevention and health promotion among pharmacists, given more focus on hospital pharmacists.

Identification of novel inhibitors against VP40 protein of Marburg virus by integrating molecular modeling and dynamics approaches.

Marburg virus (MV) is a highly etiological agent of haemorrhagic fever in humans and has spread across the world. Its outbreaks caused a 23-90% human death rate. However, there are currently no authorized preventive or curative measures yet. VP40 is the MV matrix protein, which builds protein shell underneath the viral envelope and confers hallmark filamentous. VP40 alone is able to induce assembly and budding of filamentous virus-like particles (VLPs), which resemble authentic virions. As a result, this research is credited with clarifying the function of VP40 and leading to the discovery of new therapeutic targets effective in combating MV disease (MVD). Virtual screening, molecular docking and molecular dynamics (MD) simulation were used to find the putative active chemicals based on a 3D pharmacophore model of the protein's active site cavity. Initially, andrographidine-C, a potent inhibitor was selected for the development of the pharmacophore model. Later, a library of 30,000 compounds along with the andrographidine-C was docked against VP40 protein. Three best hits including avanafil, diuvaretin and macrourone were subjected to further MD simulation analysis, as these compounds had better binding affinities as compared to andrographidine-C. Furthermore, throughout the 100 ns simulations, the back bone of VP40 protein in presence of avanafil, diuvaretin and macrourone remained stable which was further validated by MM-PBSA analysis. Additionally, all of these compounds depict maximum drug-like properties. The predicted drugs based on the ligand, avanafil, diuvaretin and macrourone could be exploited and developed as an alternative or complementary therapy for the treatment of MVD.Communicated by Ramaswamy H. Sarma.

Structure-based virtual identification of natural inhibitors of SARS-CoV-2 and its Delta and Omicron variant proteins.

Aim: Structure-based identification of natural compounds against SARS-CoV-2, Delta and Omicron target proteins. Materials & methods: Several known antiviral natural compounds were subjected to molecular docking and MD simulation against SARS-CoV-2 Mpro, Helicase and Spike, including Delta and Omicron Spikes. Results: Of the docked ligands, 20 selected for each complex exhibited overall good binding affinities (-7.79 to -5.06 kcal/mol) with acceptable physiochemistry following Lipinski's rule. Finally, two best ligands from each complex upon simulation showed structural stability and compactness. Conclusion: Quercetin-3-acetyl-glucoside, Rutin, Kaempferol, Catechin, Orientin, Obetrioside and Neridienone A were identified as potential inhibitors of SARS-CoV-2 Mpro, Helicase and Spike, while Orientin and Obetrioside also showed good binding affinities with Omicron Spike. Catechin and Neridienone A formed stable complexes with Delta Spike.

Mutant strains of SARS-CoV-2 called 'variants of concern' (VOCs) are linked to a good ability to infect, re-infect and spread among people. They are also linked to poor ability to fight the disease and reduced effectiveness of vaccines. Delta and Omicron are important VOCs because they are difficult to control and treat. Specific resistance to some drugs used to treat COVID-19 poses a further challenge. Therefore, discovering natural or plant-derived drugs with no known resistance would be valuable to the treatment of COVID-19. In this study, we screen and identify seven plant-derived compounds that may be useful to treating COVID-19 ­ we identify Quercetin-3-acetyl-glucoside, Rutin, Kaempferol, Catechin, Orientin, Obetrioside and Neridienone A as potential candidates. Orientin, Obetrioside, Catechin and Neridienone A are identified as candidates against Delta and Omicron for the first time.

Molecular docking and ADMET studies of halogenated metabolites from marine sponges as inhibitors of wild-type and mutants PBP2 in Neisseria gonorrhoeae.

Gonorrhoea is a sexually transmitted infection (STI) caused by the bacteria Neisseria gonorrhoeae. Gonorrhoea symptoms can vary, although roughly 50% of women and 10% of men infected with N. gonorrhoeae may be asymptomatic. If left untreated, gonorrhoea can cause major health problems. However, no effective treatment or vaccination is currently available. The enzyme penicillin-binding protein 2 (PBP2) is necessary for cell wall synthesis during N. gonorrhoeae cell growth. The goal of this study is to investigate the molecular interactions of three PBP2 variants with halogenated marine sponge metabolites using molecular docking, molecular dynamic simulation, and ADMET analysis. The docking findings were evaluated using the glide gscore, and the top 20 compounds docked against each PBP2 protein receptor were chosen. Furthermore, the selected compounds underwent ADMET analysis, indicating that they have the potential for therapeutic development. Among the selected compounds, Bromoageliferin had the highest affinity for PBP2, Psammaplysin E for the penicillin-resistant variation of PBP2 protein, and Preaxinellamine for the cephalosporin-resistant variant of PBP2 protein. Additionally, MM-GBSA binding free energy and molecular dynamics simulations were used to support the docking investigations. The results of the study suggest that these compounds may eventually be used to treat gonorrhoea. However, computer validations were included in this study, and more in-vitro research is required to turn these prospective inhibitors into clinical drugs.Communicated by Ramaswamy H. Sarma.

Binding selectivity analysis of AURKs inhibitors through molecular dynamics simulation studies.

Aurora kinases (AURKs) have been identified as promising biological targets for the treatment of cancer. In this study, molecular dynamics simulations were employed to investigate the binding selectivity of three inhibitors (HPM, MPY, and VX6) towards AURKA and AURKB by predicting their binding free energies. The results show that the inhibitors HPM, MPY, and VX6 have more favorable interactions with AURKB as compared to AURKA. The binding energy decomposition analysis revealed that four common residue pairs (L139, L83), (V147, V91), (L210, L154), and (L263, L207) showed significant binding energies with HPM, MPY, and VX6, hence responsible for the binding selectivity of AURKA and AURKB to the inhibitors. The MD trajectory analysis also revealed that the inhibitors affect the dynamic flexibility of protein structure, which is also responsible for the partial selectivity of HPM, MPY, and VX6 towards AURKA and AURKB. As expected, this study provides useful insights for the design of potential inhibitors with high selectivity for AURKA and AURKB.

In silico identification of deep-sea fungal alkaloids as potential inhibitors of SARS-CoV-2, Delta and Omicron spikes.

Aim: Virtual screening of deep-sea fungal metabolites against SARS-CoV-2 Delta and Omicron spikes as potential antivirals. Materials & methods: Deep-sea fungal alkaloids (n ≥ 150) were evaluated against SARS-CoV-2, Delta and Omicron spikes, using various in silico approaches, including Admet scores, physiochemical properties, molecular docking (MD) and MD simulation (150 ns). Results: The test alkaloids complied with Admet scores and physiochemical properties within acceptable ranges, and followed Lipinski's rule of five. Of these, Cladosporium sphaerospermum-derived cladosin K (tetramate alkaloid) for SARS-CoV-2, Cystobasidium laryngis-derived saphenol (phenazine alkaloid) for Delta and Chaetomium globosum-derived chaetoglobosin E (quinoline alkaloid) for Omicron were identified as potential spike-inhibitors. Conclusion: Our data therefore, strongly warrants further experimental validations of cladosin K, saphenol and chaetoglobosin E, especially against the Omicron and Delta spikes.

Therapeutic Study of Cinnamic Acid Derivative for Oxidative Stress Ablation: The Computational and Experimental Answers.

This study aimed to examine the therapeutic activity of the cinnamic acid derivative KAD-7 (N'-(2,4-dichlorobenzylidene)-3-(4-methoxyphenyl) acrylohydrazide) on Fe2+-induced oxidative hepatic injury via experimental and computational models. In addition, the role of ATPase and ectonucleoside triphosphate diphosphohydrolase (ENTPDase) in the coordination of cellular signals is speculated upon to proffer suitable therapeutics for metabolic stress disorder upon their inhibition. While we know little about therapeutics with flexible dual inhibitors for these protein targets, this study was designed to screen KAD-7's (N'-(2,4-dichlorobenzylidene)-3-(4-methoxyphenyl) acrylohydrazide) inhibitory potential for both protein targets. We induced oxidative hepatic damage via the incubation of hepatic tissue supernatant with 0.1 mM FeSO4 for 30 min at 37 °C. We achieved the treatment by incubating the hepatic tissues with KAD-7 under the same conditions. The catalase (CAT), glutathione (GSH), malondialdehyde (MDA), ATPase, and ENTPDase activity were all measured in the tissues. We predicted how the drug candidate would work against ATPase and ENTPDase targets using molecular methods. When hepatic injury was induced, there was a significant decrease in the levels of the GSH, CAT, and ENTPDase (p < 0.05) activities. In contrast, we found a noticeable rise in the MDA levels and ATPase activity. KAD-7 therapy resulted in lower levels of these activities overall (p < 0.05), as compared to the control levels. We found the compound to have a strong affinity for ATPase (-7.1 kcal/mol) and ENTPDase (-7.4 kcal/mol), and a better chemical reactivity than quercetin. It also met all drug-likeness parameters. Our study shows that KAD-7 can protect the liver from damage caused by FeSO4 by reducing oxidative stress and purinergic actions. Our studies indicate that KAD-7 could be developed as a therapeutic option since it can flexibly inhibit both ATPase and ENTPDase.

Antispasmodic Effect of Alstonia boonei De Wild. and Its Constituents: Ex Vivo and In Silico Approaches.

BACKGROUND: Alstonia boonei, belonging to the family Apocynaceae, is one of the best-known medicinal plants in Africa and Asia. Stem back preparations are traditionally used as muscle relaxants. This study investigated the antispasmodic properties of Alstonia boonei Stem back and its constituents. METHOD: The freeze-dried aqueous Stem back extract of A. boonei, as well as dichloromethane (DCM), ethyl acetate, and aqueous fractions, were evaluated for their antispasmodic effect via the ex vivo method. Two compounds were isolated from the DCM fraction using chromatographic techniques, and their antispasmodic activity was evaluated. An in silico study was conducted by evaluating the interaction of isolated compounds with human PPARgamma-LBD and human carbonic anhydrase isozyme. RESULTS: The Stem back crude extract, DCM, ethyl acetate, and aqueous fractions showed antispasmodic activity on high-potassium-induced (K+ 80 mM) contractions on isolated rat ileum with IC50 values of 0.03 ± 0.20, 0.02 ± 0.05, 0.03 ± 0.14, and 0.90 ± 0.06 mg/mL, respectively. The isolated compounds from the DCM fraction were ß-amyrin and boonein, with only boonein exhibiting antispasmodic activity on both high-potassium-induced (IC50 = 0.09 ± 0.01 µg/mL) and spontaneous (0.29 ± 0.05 µg/mL) contractions. However, ß-amyrin had a stronger interaction with the two proteins during the simulation. CONCLUSION: The isolated compounds boonein and ß-amyrin could serve as starting materials for the development of antispasmodic drugs.

Deep-sea fungal metabolites as potential inhibitors of glucose-regulatory enzymes: In silico structure-activity analysis.

Chronic diabetes mellites related hyperglycemia is a major cause of mortality and morbidity due to further complications like retinopathy, hypertension and cardiovascular diseases. Though several synthetic anti-diabetes drugs specifically targeting glucose-metabolism enzymes are available, they have their own limitations, including adverse side-effects. Unlike other natural or marine-derived pharmacologically important molecules, deep-sea fungi metabolites still remain under-explored for their anti-diabetes potential. We performed structure-based virtual screening of deep-sea fungal compounds selected by their physiochemical properties, targeting crucial enzymes viz., α -amylase, α -glucosidase, pancreatic-lipoprotein lipase, hexokinase-II and protein tyrosine phosphatase-1B involved in glucose-metabolism pathway. Following molecular docking scores and MD simulation analyses, the selected top ten compounds for each enzyme, were subjected to pharmacokinetics prediction based on their AdmetSAR- and pharmacophore-based features. Of these, cladosporol C, tenellone F, ozazino-cyclo-(2,3-dihydroxyl-trp-tyr), penicillactam and circumdatin G were identified as potential inhibitors of α -amylase, α -glucosidase, pancreatic-lipoprotein lipase, hexokinase-II and protein tyrosine phosphatase-1B, respectively. Our in silico data therefore, warrants further experimental and pharmacological studies to validate their anti-diabetes therapeutic potential.

Computational evaluation of marine demospongiae sponges metabolites activity as mycolic acid biosynthesis inhibitors in Mycobacterium tuberculosis.

Background: Mycobacterium tuberculosis is a bacterium that has historically had a substantial impact on human health. Despite advances in understanding and management of tuberculosis (TB), the disease remains a crucial problem that necessitates ongoing work to discover effective drugs, minimize transmission, and improve global health outcomes. Methods: The purpose of this study is to use molecular docking and absorption, distribution, metabolism, excretion, and toxicity (ADMET) analyses to explore the molecular interactions of different proteins that are involved in mycolic acid biosynthesis (HadAB, InhA, KasA, FabD, and beta-ketoacyl-acyl carrier protein synthase III) of M. tuberculosis with Demospongiae metabolites. The docking findings were evaluated using the glide gscore, and the top 10 compounds docked against each protein receptor were chosen. Furthermore, the selected compounds underwent ADMET analysis, indicating that they have the potential for therapeutic development. Results: Among the selected compounds, makaluvamine G showed the highest binding affinity against HadAB, psammaplysin E showed highest binding affinity against InhA, pseudotheonamide D showed the highest binding affinity against KasA protein, dinordehydrobatzelladine B showed the highest binding affinity against FabD, and nagelamide X showed the highest binding affinity against beta-ketoacyl-acyl carrier protein synthase III. Additionally, molecular mechanics generalized born surface area (MM-GBSA) binding free energy and molecular dynamics simulations were used to support the docking investigations. Conclusion: The results of the study suggest that these compounds may eventually be used to treat TB. However, computer validations were included in this study, and more in vitro research is required to turn these prospective inhibitors into clinical drugs.

Association of CYP2C9*2 Allele with Sulphonylurea-Induced Hypoglycaemia in Type 2 Diabetes Mellitus Patients: A Pharmacogenetic Study in Pakistani Pashtun Population.

Polymorphism in cytochrome P450 (CYP) 2C9 enzyme is known to cause significant inter-individual differences in drug response and occurrence of adverse drug reactions. Different alleles of the CYP2C9 gene have been identified, but the notable alleles responsible for reduced enzyme activity are CYP2C9*2 and CYP2C9*3. No pharmacogenetic data are available on CYP2C9*2 and CYP2C9*3 alleles in the Pakistani population. In Pakistan, pharmacogenetics, which examines the relationship between genetic factors and drug response, are in the early stages of development. We, for the first time, investigated the association between the CYP2C9 variant alleles CYP2C9*2 and CYP2C9*3 and the incidence of hypoglycaemia in patients with Type 2 diabetes mellitus (T2DM) receiving sulphonylurea medications. A total of n = 400 individuals of Pashtun ethnicity were recruited from 10 different districts of Khyber Pakhtunkhwa, Pakistan to participate in the study. The study participants were divided into two distinct groups: the case group (n = 200) and the control group (n = 200). The case group consisted of individuals with T2DM who were receiving sulphonylurea medications and experienced hypoglycaemia with it, whereas the control group included individuals with T2DM who were receiving sulphonylurea medication but did not experience sulphonylurea-induced hypoglycaemia (SIH). Blood samples were obtained from study participants following informed consent. DNA was isolated from whole blood samples using a Wiz-Prep DNA extraction kit. Following DNA isolation, CYP2C9 alleles were genotyped using MassARRAY sequencing platform at the Centre of Genomics at the Rehman Medical Institute (RMI). The frequency of CYP2C9*2 (low-activity allele) was more frequent in the diabetic patients with SIH compared to the control group (17.5% vs. 6.0%, p = 0.021). The frequency of its corresponding genotype CYP2C9*1/*2 was higher in cases compared to the control group (10% vs. 6% with p = 0.036); the same was true for genotype CYP2C9*2/*2 (7% vs. 3.5% with p = 0.028). Logistic regression analysis evidenced potential association of CYP2C9*2 allele and its genotypes with SIH. When adjusted for confounding factors such as age, weight, sex, mean daily dose of sulphonylurea, and triglyceride level, the association between the CYP2C9*2 allele and hypoglycaemia remained consistent. Confounding factors played no role in SIH (insignificant p-value) because both groups (cases and controls) were closely matched in term of age, weight, sex, mean daily dose of sulphonylurea, and triglyceride levels. Our study suggests that genetic information about a patient's CYP2C9 gene/enzyme can potentially assist physicians in prescribing the most suitable and safest drug, based on their genetic make-up.

The ameliorative effect of bergamot oil nano-emulsion in stressed rabbit bucks: Influence on blood biochemical parameters, redox status, immunity indices, inflammation markers, semen quality, testicular changes and the expression of HSPs genes.

This work explored the activities of bergamot oil nano-emulsion (NBG) in modulating blood biochemical parameters, redox status, immunity indices, inflammation markers, semen quality, testicular changes and the expression of HSPs genes in stressed rabbit bucks. Twenty-four mature rabbit bucks (5 months) were randomly divided into three groups; control group (NBG0) received 1 ml of distilled water, while the other two groups received NBG orally at doses of 50 and 100 mg/kg (bw) twice a week. The present study's findings revealed that treated groups had lower values of total and direct bilirubin, triglyceride, lactate dehydrogenase, and creatinine compared with NBG0 group (p < 0.05). NBG100 group recorded the greatest of total protein, albumin, GPx, T3 and T4 values as well as the lowest values of uric acid, MDA, and indirect bilirubin. Both treated groups showed significantly reduced 8-OhDG, Amyloid A, TLR 4, while significantly increased nitric oxide, IgA, IgM, TAC, and SOD levels. Semen characteristics such as volume, sperm count, sperm motility, normal sperm, and vitality were significantly higher in the NBG100 group compared to the NBG50 and NBG0 groups, whereas sperm abnormalities and dead sperm were significantly reduced. HSP70, HSP72, and HSPA9 gene overexpression showed that testicular integrity was maintained after buck received oral doses of 50 or 100 mg/kg of NBG. Existing findings indicate that oral administration of NBG improves heat tolerance in rabbit bucks primarily as e result of its antioxidant and anti-inflammatory effects.

Inhibition of hepatitis B virus activities by Rhazya stricta­derived acacetin and acetyl­ß­carboline.

Hepatitis B virus (HBV) causes acute and chronic liver diseases, leading to cirrhosis and hepatocellular carcinoma. Although direct-acting nucleoside analogs, such as lamivudine (LAM), adefovir and famciclovir, are available, emergence of drug-resistance due to mutations in HBV polymerase (POL) restricts their further use. Alternatively, numerous plant products and compounds isolated from plants have been reported to confer anti-HBV efficacies without any sign of resistance in vitro or in vivo. As, flavonoids and alkaloids are the most widely reported antivirals, the anti-HBV activities of the flavonoid acacetin (ACT) and the alkaloid acetyl-ß-carboline (ABC) from the aerial parts of Rhazya stricta were assessed in the present study. Both compounds were isolated from the ethyl acetate fraction of the total methanol extract using column and thin-layer chromatography, and their structures were determined by nuclear magnetic resonance spectroscopy (NMR). Both compounds (at 6.25-50 µg/ml) showed a lack of hepatocytotoxicity in cultured HepG2.2.15 cells. Anti-HBV ELISA [hepatitis B surface antigen (HBsAg) and hepatitis B pre-core-antigen (HBeAg)] on HepG.2.2.15 cells following treatment with selected concentrations (12.5, 25 and 50 µg/ml) of both compounds showed dose- and time-dependent anti-HBV activities. Compared with those in the untreated control at day 5, ACT and ABC (25 µg/ml, each) maximally inhibited HBsAg synthesis by 43.4 and 48.7%, respectively, whilst also maximally inhibiting HBeAg synthesis by 41.2 and 44.2%, respectively, in HepG2.2.15 cells. Comparatively, quercetin and LAM (standards; POL inhibitors) suppressed HBsAg (63.9 and 60.2%, respectively) and HBeAg synthesis (87.1 and 84.3%, respectively) by larger magnitudes. Molecular docking of ACT and ABC structures performed in AutoDock revealed their hydrogen bonding with the drug-sensitive [wild-type (wt)-POL] 'Tyr-Met-Asp-Asp' motif, in addition to the drug-resistant [mutant (mut)-POL] 'Tyr-Ile-Asp-Asp' motif residues of the polymerase binding-pocket, along with other electrostatic interactions. In the wt-POL complex, both compounds showed good interactions with Asp205. In the mut-POL complex, ACT and ABC interacted with Tyr203-Asp205 and Tyr203-Ile204, respectively. In conclusion, to the best of our knowledge, the present study demonstrates anti-HBV efficacies of ACT and ABC in vitro for the first time, endorsed by in silico data. However, further molecular and pharmacological studies are required to validate their pre-clinical therapeutic potential.

A molecularly imprinted electrochemical sensor for specific and ultrasensitive determination of an aminoglycoside drug: the role of copper ions in the determination.

Herein, a molecularly imprinted polymer (MIP) was fabricated for specific sensing of an aminoglycoside e.g. kanamycin (KANA). Carbon paste modified with a MIP specific to Cu2+-KANA was first introduced. Copper (Cu2+) as a metal ion was used as a signal tracer and an amplifier, producing a current response measured by differential pulse voltammetry (DPV). Introducing the aminoglycoside drug into the solution containing Cu2+ did not affect the current response of the NIP/CPE. Under the optimum conditions, the as-fabricated sensor exhibited an increase in the current response in the range of 0.55-550 nM with a good limit of detection (LOD, S/N = 3) of 161 pM. The sensor exhibited many advantages including high sensitivity and selectivity, good stability and reproducibility, and cost-effectiveness. Moreover, it was successfully applied for the determination of KANA in milk and honey samples with RSD % not more than 3.3%, suggesting the reliability of the as-designed sensor.

Antimicrobial Activity of Dihydroisocoumarin Isolated from Wadi Lajab Sediment-Derived Fungus Penicillium chrysogenum: In Vitro and In Silico Study.

Antibiotic resistance is considered a major health concern globally. It is a fact that the clinical need for new antibiotics was not achieved until now. One of the most commonly prescribed classes of antibiotics is ß-Lactam antibiotics. However, most bacteria have developed resistance against ß-Lactams by producing enzymes ß-Lactamase or penicillinase. The discovery of new ß-Lactamase inhibitors as new antibiotics or antibiotic adjuvants is essential to avoid future catastrophic pandemics. In this study, five dihydroisocoumarin: 6-methoxy mellein (1); 5,6-dihydroxymellein (2); 6-hydroxymellein (3); 4-chloro-6-hydroxymellein (4) and 4-chloro-5,6-di-hydroxymellein (5) were isolated from Wadi Lajab sediment-derived fungus Penicillium chrysogenum, located 15 km northwest of Jazan, KSA. The elucidation of the chemical structures of the isolated compounds was performed by analysis of their NMR, MS. Compounds 1-5 were tested for antibacterial activities against Gram-positive and Gram-negative bacteria. All of the compounds exhibited selective antibacterial activity against Gram-positive bacteria Staphylococcus aureus and Bacillus licheniformis except compound 3. The chloro-dihydroisocoumarin derivative, compound 4, showed potential antimicrobial activities against all of the tested strains with the MIC value between 0.8-5.3 µg/mL followed by compound 5, which exhibited a moderate inhibitory effect. Molecular docking data showed good affinity with the isolated compounds to ß-Lactamase enzymes of bacteria; NDM-1, CTX-M, OXA-48. This work provides an effective strategy for compounds to inhibit bacterial growth or overcome bacterial resistance.

Novel anti-hepatitis B virus-active catechin and epicatechin from Rhus tripartita.

Bioactive natural or phytoproducts have emerged as a potential source of antiviral agents. Of the Rhus spp., R. coriaria and R. succedanea have been reported for their antiviral activities against hepatitis B virus (HBV), while the anti-HBV efficacy of R. tripartita has remained elusive. In the present study, the anti-HBV activities of R. tripartita-derived novel catechin [3,5,13,14-flavantetrol-catechin or rhuspartin (RPT)] and epicatechin-3-O-rhamnoside (ECR), were assessed using the HBV-reporter cell line HepG2.2.15. RPT and ECR proved to efficiently inhibit HBV surface antigen (HBsAg) synthesis by 68.8 and 71.3%, respectively, and HBV pre-core antigen (HBeAg) production by 62.3 and 71.2%, respectively, after 5 days of treatment. Of note, RPT had a lower anti-HBV activity than ECR. In comparison, the reference drug lamivudine (LAM) inhibited HBsAg and HBeAg expression by 83.6 and 85.4%, respectively. Further molecular docking analysis revealed formations of strong complexes of RPT, ECR and LAM with HBV polymerase through interactions with binding pocket residues. Taken together, the present results demonstrated promising therapeutic potential of the novel R. tripartita-derived catechin and epicatechin for HBV, warranting their further molecular and pharmacological evaluation.

Global and pathway-specific transcriptional regulations of pactamycin biosynthesis in Streptomyces pactum.

Pactamycin, a structurally unique aminocyclitol natural product isolated from Streptomyces pactum, has potent antibacterial, antitumor, and anti-protozoa activities. However, its production yields under currently used culture conditions are generally low. To understand how pactamycin biosynthesis is regulated and explore the possibility of improving pactamycin production in S. pactum, we investigated the transcription regulations of pactamycin biosynthesis. In vivo inactivation of two putative pathway-specific regulatory genes, ptmE and ptmF, resulted in mutant strains that are not able to produce pactamycin. Genetic complementation using a cassette containing ptmE and ptmF integrated into the S. pactum chromosome rescued the production of pactamycin. Transcriptional analysis of the ΔptmE and ΔptmF strains suggests that both genes control the expression of the whole pactamycin biosynthetic gene cluster. However, attempts to overexpress these regulatory genes by introducing a second copy of the genes in S. pactum did not improve the production yield of pactamycin. We discovered that pactamycin biosynthesis is sensitive to phosphate regulation. Concentration of inorganic phosphate higher than 2 mM abolished both the transcription of the biosynthetic genes and the production of the antibiotic. Draft genome sequencing of S. pactum and bioinformatics studies revealed the existence of global regulatory genes, e.g., genes that encode a two-component PhoR-PhoP system, which are commonly involved in secondary metabolism. Inactivation of phoP did not show any significant effect to pactamycin production. However, in the phoP::aac(3)IV mutant, pactamycin biosynthesis is not affected by external inorganic phosphate concentration.

Biosynthesis and Metabolic Engineering of Pseudo-oligosaccharides.

Pseudo-oligosaccharides are microbial-derived secondary metabolites whose chemical structures contain pseudosugars (glycomimetics). Due to their high resemblance to the molecules of life (carbohydrates), most pseudo-oligosaccharides show significant biological activities. Some of them have been used as drugs to treat human and plant diseases. Because of their significant economic value, efforts have been put into understanding their biosynthesis, optimizing their fermentation conditions, and engineering their metabolic pathways to obtain better production yields. A number of unusual enzymes participating in diverse biosynthetic pathways to pseudo-oligosaccharides have been reported. Various methods and conditions to improve the production yields of the target compounds and eliminate byproducts have also been developed. This review article describes recent studies on the biosynthesis, fermentation optimization, and metabolic engineering of high-value pseudo-oligosaccharides.