Unraveling Potential Glyoxalase-I Inhibitors Utilizing Structure-Based Drug Design Techniques.

Background: Glyoxalase system detoxifies methylglyoxal and other ketoaldehydes to produce innocuous metabolites that allow the cells to function normally. Its inhibition in cancer cells causes these toxic metabolites to accumulate, and the cancer cells enter the apoptotic stage. Methods: The techniques of Computer-Aided Drug Design (CADD) were used, and the compounds possessing a zinc-binding group from commercial databases were extracted, using the pharmacophore search protocol. These compounds were subjected to robust docking using the CDOCKER protocol within the Discovery Studio. Docking was performed on both Glo-I twin active sites. The biological activities of candidate hits were assessed using an in vitro assay against Glo-I. Results: Compounds containing zinc-binding groups were extracted from ASINEX® commercial database, which contains (91,001 compounds). This step has helped to retrieve 1809 ligands, which then were prepared and docked at the two active sites of Glo-I. The fourteen compounds, which have showed the highest scores in docking and returned acceptable Total Binding Energy values, were purchased and tested against the enzyme in vitro. Two compounds out of the fourteen, which were selected in the final step, possess tetrazole ring as zinc chelating moiety, and have showed moderate activity with an IC50 of 48.18µM for SYN 25285236 and 48.77 µM for SYN 22881895. Conclusion: Two hits with moderate activity are identified as the lead compounds against Glo-I. Both compounds possess a negatively ionized tetrazole ring as the zinc-binding moiety. These compounds will lead to the development of inhibitors with improved activities.

Computational fragment-based drug design of potential Glo-I inhibitors.

In this study, a fragment-based drug design approach, particularly de novo drug design, was implemented utilising three different crystal structures in order to discover new privileged scaffolds against glyoxalase-I enzyme as anticancer agents. The fragments were evoluted to indicate potential inhibitors with high receptor affinities. The resulting compounds were served as a benchmark for choosing similar compounds from the ASINEX® database by applying different computational ligand-based drug design techniques. Afterwards, the selection of potential hits was further aided by various structure-based approaches. Then, 14 compounds were purchased, and tested in vitro against Glo-I enzyme. Of the tested 14 hits, the biological screening results showed humble activities where the percentage of Glo-I inhibition ranged from 0-18.70 %. Compound 19 and compound 28, whose percentage of inhibitions are 18.70 and 15.80%, respectively, can be considered as hits that need further optimisation in order to be converted into lead-like compounds.

Lead optimization and biological evaluation of diazenylbenzenesulfonamides inhibitors against glyoxalase-I enzyme as potential anticancer agents.

In a previous report, we described the discovery of (E)-5-((8-hydroxyquinolin-5-yl)diazenyl)-2-methylbenzenesulfonamide as a potent inhibitor of GLO-I enzyme with IC50 of 1.28 ± 0.12 µM. Herein, lead optimization of this compound was achieved through targeting the central zinc atom and hydrophilic amino acid residues in the active site of the enzyme. Among the synthesized compounds, compound TS010 showed the most potent inhibitory activity with IC50 of 0.57 ± 0.04 µM. Compound TS013 also showed comparable activity to that of the lead compound with IC50 of 1.14 ± 0.03 µM. Molecular docking studies disclosed the binding mode of the compounds inside the active side of GLO-I enzyme.

Computational medicinal chemistry role in clinical pharmacy education: Ingavirin for coronavirus disease 2019 (COVID-19) discovery model.

Objective: Given the major shift to patient-directed education, novel coronavirus (nCoV) provides a live example on how medicinal chemistry could be a key science to teach pharmacy students. In this paper, students and clinical pharmacy practitioners will find a stepwise primer on identifying new potential nCoV treatments mechanistically modulated through angiotensin-converting enzyme 2 (ACE2). Methods: First, we identified the maximum common pharmacophore between carnosine and melatonin as background ACE2 inhibitors. Second, we performed a similarity search to spot out structures containing the pharmacophore. Third, molinspiration bioactivity scoring enabled us to promote one of the newly identified molecules as the best next candidate for nCoV. Preliminary docking in SwissDock and visualization through University of California San Francisco (UCSF) chimera made it possible to qualify one of them for further detailed docking and experimental validation. Results: Ingavirin had the best docking results with full fitness of -3347.15 kcal/mol and estimated ΔG of -8.53 kcal/mol compared with melatonin (-6.57 kcal/mol) and carnosine (-6.29 kcal/mol). UCSF chimera showed viral spike protein elements binding to ACE2 retained in the best ingavirin pose in SwissDock at 1.75 Angstroms. Conclusion: Ingavirin has a promising inhibitory potential to host (ACE2 and nCoV spike protein) recognition, and hence could offer the next best mitigating effect against the current coronavirus disease (COVID-19) pandemic.

Identification of the First "Two Digit Nano-molar" Inhibitors of the Human Glyoxalase-I Enzyme as Potential Anticancer Agents.

BACKGROUND: Glyoxalase-I (Glo-I) enzyme is recognized as an indispensable druggable target in cancer treatment. Its inhibition will lead to the accumulation of toxic aldehyde metabolites and cell death. Paramount efforts were spent to discover potential competitive inhibitors with the aim to eradicate cancer. OBJECTIVE: Based on our previous work on this target for discovering potent inhibitors of this enzyme, herein, we address the discovery of the most potent Glo-I inhibitors reported in the literature with two digits nano-molar activity. METHODS: Molecular docking and in vitro assay were performed to discover these inhibitors and explore the binding pattern within the active site. A detailed SAR scheme was generated, which identifies the major functionalities responsible for the observed activity. RESULTS: Compound 1 with an IC50 of 16.5 nM exhibited the highest activity, which possess catechol moiety as an essential zinc chelating functionality. It has been shown by using molecular modeling techniques that the catechol moiety is responsible for chelation zinc atom at the active site; an essential feature for enzyme inhibition. CONCLUSION: Catechol derivatives are successful zinc chelators in Glo-I enzyme while showing exceptional activity against the enzyme to nanomolar level.

An Ethical Roadmap for Prioritizing Medical Resources Within Muslim Societies During the COVID-19 Pandemic.

Profound ethical challenges have been generated by the emergence of the COVID-19 pandemic. The unprecedented plights that have arisen have led nations to devise ethical roadmaps for handling their finite resources. Muslim countries are no exception and must continue to endure the effects of the pandemic, as more waves of infections from new strains are being reported. Given the scarcity of resources available to some countries, it is critical to adopt a roadmap to prioritize these limited resources based on ethical guidelines that are acceptable to Muslim communities. This work describes the concept of "ijtihad", a process frequently used by Muslim scholars to develop novel solutions to deal with unprecedented events, such as the recent pandemic. In this manuscript, Islamic perspectives were discussed on social justice and equality and how limited resources can be used in a way consistent with such perspectives. Relying on previous experiences of the Muslim community, such as the plague of Amwas, in which social distancing and quarantine strategies were used effectively to control the disease, and utilizing available guidelines such as "Al-Qawaid Al-Fiqhiyyah" and "Fiqh Al-Nawazel", we propose a practical protocol and roadmap that can be applied in the current crisis. Managing and prioritizing limited medical resources requires a just and ethically acceptable system. Islamic leaders should immediately develop a roadmap that emphasizes ethical values such as ihsan and altruism to help Muslim countries prioritize the limited medical resources available to medical staff to guarantee the sustainability of health services.

The ethics of practicing defensive medicine in Jordan: a diagnostic study.

BACKGROUND: Defensive medicine (DM) practice refers to the ordering or prescription of unnecessary treatments or tests while avoiding risky procedures for critically ill patients with the aim to alleviate the physician's legal responsibility and preserve reputation. Although DM practice is recognized, its dimensions are still uncertain. The subject has been highly investigated in developed countries, but unfortunately, many developing countries are unable to investigate it properly. DM has many serious ramifications, exemplified by the increase in treatment costs for patients and health systems, patients' exposure to risks, and negative effects on the psychological health of both health providers and recipients. Ultimately, the most serious consequence is the ethical consequences. METHODS: This work is based on a review of the literature related to DM worldwide and a comparison with the available knowledge found in Jordan. It is qualitative with a descriptive nature, aiming to diagnose the current DM practice in Jordan. RESULTS: This is the first published article that discusses DM in Jordan by diagnosing its ethical and economic consequences for the health system as well as for patients. Despite the knowledge of the reasons that support its practice, little is being done to solve this issue. The absence of agreeable medical malpractice law, the dearth of unified medical protocols, the overwhelming pressure imposed by patients on medical staff, and the deteriorating patient-physician relationship are some of the causes of DM practice. Surely, the solution to these issues is to focus on fortifying the ethical and humanitarian aspects on the side of both the physician and the patient to ensure positive collaboration. The ethical aim of the physician to treat the patient faithfully and do what is possible to help combined with the appreciation of the physician's efforts and the choice to not take advantage of the physician through litigation could be the most reasonable solution in the near future. CONCLUSION: Jordan is suffering from DM due to the limited financial expenditure on the health sector and the impracticality of medical malpractice law. The authors highlight that the cardinal step in solving this dilemma is restoring the ethical dimension of the patient-physician relationship.

Ellagic acid: A potent glyoxalase-I inhibitor with a unique scaffold.

The glyoxalase system, particularly glyoxalase-I (GLO-I), has been approved as a potential target for cancer treatment. In this study, a set of structurally diverse polyphenolic natural compounds were investigated as potential GLO-I inhibitors. Ellagic acid was found, computationally and experimentally, to be the most potent GLO-I inhibitor among the tested compounds which showed an IC50 of 0.71 mmol L-1. Its binding to the GLO-I active site seemed to be mainly driven by ionic interaction via its ionized hydroxyl groups with the central Zn ion and Lys156, along with other numerous hydrogen bonding and hydrophobic interactions. Due to its unique and rigid skeleton, it can be utilized to search for other novel and potent GLO-I inhibitors via computational approaches such as pharmacophore modeling and similarity search methods. Moreover, an inspection of the docked poses of the tested compounds showed that chlorogenic acid and dihydrocaffeic acid could be considered as lead compounds worthy of further optimization.

Design, synthesis and biological evaluation of novel glyoxalase I inhibitors possessing diazenylbenzenesulfonamide moiety as potential anticancer agents.

The enzyme glyoxalase-I (Glo-I) is an essential therapeutic target in cancer treatment. Significant efforts have been made to discover competitive inhibitors of Glo-I as potential anticancer agents. Herein, we report the synthesis of a series of diazenylbenzenesulfonamide derivatives, their in vitro evaluation against Glo-I and the resulting structure-activity relationships. Among the compounds tested, compounds 9h and 9j exhibited the highest activity with IC50 1.28 µM and 1.13 µM, respectively. Docking studies to explore the binding mode of the compounds identified key moieties that may contribute to the observed activities. The active compounds will serve as suitable leads for further chemical optimization.

Identification of Human Leukotriene A4 Hydrolase Inhibitors Using Structure-Based Pharmacophore Modeling and Molecular Docking.

Leukotriene B4 (LTB4) is a potent, proinflammatory lipid mediator implicated in the pathologies of an array of inflammatory diseases and cancer. The biosynthesis of LTB4 is regulated by the leukotriene A4 hydrolase (LTA4H). Compounds capable of limiting the formation of LTB4, through selective inhibition of LTA4H, are expected to provide potent anti-inflammatory and anti-cancer agents. The aim of the current study is to obtain potential LTA4H inhibitors using computer-aided drug design. A hybrid 3D structure-based pharmacophore model was generated based on the crystal structure of LTA4H in complex with bestatin. The generated pharmacophore was used in a virtual screen of the Maybridge database. The retrieved hits were extensively filtered, then docked into the active site of the enzyme. Finally, they were consensually scored to yield five hits as potential LTA4H inhibitors. Consequently, the selected hits were purchased and their biological activity assessed in vitro against the epoxide hydrolase activity of LTA4H. The results were very promising, with the most active compound showing 73.6% inhibition of the basal epoxide hydrolase activity of LTA4H. The results from this exploratory study provide valuable information for the design and development of more potent and selective inhibitors.

The Ethics of Gene Editing from an Islamic Perspective: A Focus on the Recent Gene Editing of the Chinese Twins.

In light of the development of "CRISPR" technology, new promising advances in therapeutic and preventive approaches have become a reality. However, with it came many ethical challenges. The most recent worldwide condemnation of the first use of CRISPR to genetically modify a human embryo is the latest example of ethically questionable use of this new and emerging field. Monotheistic religions are very conservative about such changes to the human genome and can be considered an interference with God's creation. Moreover, these changes could cause perpetual changes to future generations. The Muslim scholars establish their decisions by addressing five foundations of Islamic law i.e. "maqasid al sharī`a"; the purposes of the law. These are din̄ (religion), nafs (life), nasl (progeny), `aql (intellect) and mal (wealth). To achieve this, the five principles should all be met before approval of an experiment like the Chinese embryo modifications; Qasd (intention) which is achieved in this case as it aims to protect the embryo from HIV. Yaqin̄ (certainty) and Darar (injury) were not satisfied as they require strong scientific certainty of the procedures, and evidence of safety. Darura (necessity) by which the alternatives being compared; in this case more established and proven safe alternatives to protect the HIV transmission from the father are available, so this principle is not met. The final principle is `Urf (custom), by which the social context of using any contemporary technology should be taken in consideration, and clearly this was not achieved. Collectively, germline changes are rejected from an Islamic perspective until the five principles are fulfilled. In the Chinese Twins gene editing case, there was clearly no justification or support for it according to the Muslim Jurisprudence laws. These laws and approaches can serve as an ethical checklist for such controversial research, especially in early stages of the research.

Combined High Throughput Screening with QSAR Analysis Unravelling Potential Glyoxalase-I Inhibitors.

AIMS: Discovery of new Glo-I inhibitors as potential anticancer agents. BACKGROUND: Glyoxalase system is ubiquitous system in human cells which has been examined thoroughly for its role in cancerous diseases. It performs detoxifying endogenous harmful metabolites, mainly methylglyoxal (MG) into non-toxic bystanders. OBJECTIVE: Structure based model Hypo(2ZA0_2_02) combined with 3D-QSAR modeling were applied to predict glyoxalase I inhibition and to explain their activity. METHODS: Currently, high throughput screening approach was used to investigate the activity of inhouse database composed of 205 compounds. RESULTS: 15 compounds were found active as glyoxalase I inhibitors. The 15 candidates showed more than 50% inhibition with low micromolar IC50 ranges between 5.0 to 42.0 µM. CONCLUSION: They have been successfully mapped and fitted the Hypo(2ZA0_2_02) model which explain the presence of anti-glyoxalase I activity. This model could be used in future for further development of new and novel glyoxylase I inhibitors.

Discovery of a nanomolar inhibitor of the human glyoxalase-I enzyme using structure-based poly-pharmacophore modelling and molecular docking.

The glyoxalase-I (GLO-I) enzyme, which is the initial enzyme of the glyoxalase system that is responsible for the detoxification of cytotoxic α-ketoaldehydes, such as methylglyoxal, has been approved as a valid target in cancer therapy. Overexpression of GLO-I has been observed in several types of carcinomas, including breast, colorectal, prostate, and bladder cancer. In this work we aimed to identify potential GLO-I inhibitors via employing different structure-based drug design techniques including structure-based poly-pharmacophore modelling, virtual screening, and molecular docking. Poly-pharmacophore modelling was applied in this study in order to thoroughly explore the binding site of the target enzyme, thereby, revealing hits that could bind in a nonconventional way which can pave the way for designing more potent and selective ligands with novel chemotypes. The modelling phase has resulted in the selection of 31 compounds that were biologically evaluated against human GLO-I enzyme. Among the tested set, seven compounds showed excellent inhibitory activities with IC50 values ranging from 0.34 to 30.57 µM. The most active compound (ST018515) showed an IC50 of 0.34 ± 0.03 µM, which, compared to reported GLO-I inhibitors, can be considered a potent inhibitor, making it a good candidate for further optimization towards designing more potent GLO-I inhibitors.

Multi-Armed 1,2,3-Selenadiazole and 1,2,3-Thiadiazole Benzene Derivatives as Novel Glyoxalase-I Inhibitors.

Glyoxalase-I (Glo-I) enzyme was established to be a valid target for anticancer drug design. It performs the essential detoxification step of harmful byproducts, especially methylglyoxal. A robust computer-aided drug design approach was used to design and validate a series of compounds with selenium or sulfur based heterorings. A series of in-house multi-armed 1,2,3-selenadiazole and 1,2,3-thiadiazole benzene derivatives were tested for their Glo-I inhibitory activity. Results showed that these compounds bind Glo-I active sites competitively with strong potential to inhibit this enzyme with IC50 values in micro-molar concentration. Docking poses revealed that these compounds interact with the zinc atom at the bottom of the active site, which plays an essential role in its viability.

Withania somnifera root powder protects againist post-traumatic stress disorder-induced memory impairment.

Post-traumatic stress disorder (PTSD) is precipitated by exposure to severe traumatic events such as wars, natural disasters, catastrophes, or other traumatic events. Withania somnifera (WS) Dunal (family: Solanaceae) known traditionally as "Ashwaghanda" is used widely in ayurvedic medicine, and known to have positive role in neurodegenerative diseases. In this study, WS effect on impairment of memory due to PTSD was studied in animal models. Single-prolonged stress rat model, which consisted of restrain for 2 h, forced swimming for 20 min, rest for 15 min, and diethyl ether exposure for 1-2 min, was used to induce PTSD animals. The WS root powder extract was administered orally at a dose of 500 mg/kg/day. The radial arm water maze (RAWM) was used to assess spatial learning and memory. Enzymatic assays were used to evaluate changes in oxidative stress biomarkers in the hippocampus following treatments. The result showed that PTSD resulted in short- and long- term memory impairments. Administration of WS prevented this impairment of memory induced by PTSD. Furthermore, WS prevented PTSD induced changes in oxidative stress biomarker in the hippocampus. For quality assessment, the methanolic extract for WS was subjected to UHPLC analysis. A calibration curve for isowithanone as a marker compound was constructed. WS roots content of isowithanone was found to be 0.23% (w/w). In conclusion, WS administration prevented PTSD induced memory impairment probably through preserving changes in antioxidant mechanisms in the hippocampus.

Combination of pharmacophore modeling and 3D-QSAR analysis of potential glyoxalase-I inhibitors as anticancer agents.

Glyoxalase system is an ubiquitous system in human cells which has been examined thoroughly for its role in different diseases. It comprises two enzymes; Glyoxalase I (Glo-I) and Glyoxalase II (Glo-II) which perform detoxifying endogenous harmful metabolites, mainly methylglyoxal (MG) into non-toxic bystanders. In silico computer Aided Drug Design approaches were used and ninety two diverse pharmacophore models were generated from eighteen Glyoxalase I crystallographic complexes. Subsequent QSAR modeling followed by ROC evaluation identified a single pharmacophore model which was able to predict the expected Glyoxalase I inhibition. Screening of the National Cancer Institute (NCI) database using the optimal pharmacophore Hypo(3VW9) identified several promising hits. Thirty eight hits were successfully predicted then ordered and evaluated in vitro. Seven hits out of the thirty eight tested compounds showed more than 50% inhibition with low micromolar IC50.

Molecular Dynamics Simulations of Adenosine Receptors: Advances, Applications and Trends.

Adenosine receptors (ARs) are transmembrane proteins that belong to the G protein-coupled receptors (GPCRs) superfamily and mediate the biological functions of adenosine. To date, four AR subtypes are known, namely A1, A2A, A2B and A3 that exhibit different signaling pathways, tissue localization, and mechanisms of activation. Moreover, the widespread ARs and their implication in numerous physiological and pathophysiological conditions had made them pivotal therapeutic targets for developing clinically effective agents. The crystallographic success in identifying the 3D crystal structures of A2A and A1 ARs has dramatically enriched our understanding of their structural and functional properties such as ligand binding and signal transduction. This, in turn, has provided a structural basis for a larger contribution of computational methods, particularly molecular dynamics (MD) simulations, toward further investigation of their molecular properties and designing bioactive ligands with therapeutic potential. MD simulation has been proved to be an invaluable tool in investigating ARs and providing answers to some critical questions. For example, MD has been applied in studying ARs in terms of ligand-receptor interactions, molecular recognition, allosteric modulations, dimerization, and mechanisms of activation, collectively aiding in the design of subtype selective ligands. In this review, we focused on the advances and different applications of MD simulations utilized to study the structural and functional aspects of ARs that can foster the structure-based design of drug candidates. In addition, relevant literature was briefly discussed which establishes a starting point for future advances in the field of drug discovery to this pivotal group of drug targets.

Recent Advances in Glyoxalase-I Inhibition.

Glyoxalase system is a ubiquitous system in human cells which has been examined thoroughly for its role in different disease conditions. It is composed of Glyoxalase-I (Glo-I) and Glyoxalase- II which perform an essential metabolic process inside the cell by detoxifying endogenous harmful metabolites, mainly methylglyoxal (MG) into non-toxic D-lactic acid. Tumor cells are well-known for their high metabolic rate which results in elevated levels of toxic metabolites. The over-expression of Glo-I in tumor cells makes this enzyme a pivotal target for anticancer drug development. Glo-I is metalloenzyme with two polypeptide chains and encompasses two active sites with an integral zinc atoms at their center. This review aims to highlight the important role of Glo-I in different pathogenic conditions, and more importantly, it provides a thorough discussion of all known human Glo-I inhibitors since its discovery, a hundred years ago, up to date. It embraces the different classes they belong to, their design and chemical structures. We believe this review will help guide the design of novel and potent human Glo-I inhibitors by providing a handy reference for interested researchers in this target.

Computational and experimental exploration of the structure-activity relationships of flavonoids as potent glyoxalase-I inhibitors.

Hit, Lead & Candidate Discovery Glyoxalase-I (Glo-I) enzyme has emerged as a potential target for cancer treatment. Several classes of natural products including coumarins and flavonoids have shown remarkable Glo-I inhibitory activity. In the present study, computational and experimental approaches were used to explore the structure-activity relationships of a panel of 24 flavonoids as inhibitors of the Glo-1 enzyme. Scutellarein with an IC50 value of 2.04 µM was identified as the most potent inhibitor among the series studied. Di- or tri-hydroxylation of the benzene rings A and B accompanied with a C2/C3 double bond in ring C were identified as essential structural features for enzyme inhibition. Moreover, the ketol system showed a minor role in the inhibitory power of these compounds. The structure-activity relationships revealed in this study had deepened our understanding of the Glo-I inhibitory activities of flavonoids and opened the door for further exploration of this promising compound class.