Nelfinavir Research Articles

Optimizing rosemary oil nanoemulsion loaded with nelfinavir and epigallocatechin gallate: A Design Expert® endorsed approach for enhanced neuroAIDS management

This study focuses on optimizing the delivery of Nelfinavir (NFV), a vital protease inhibitor in antiretroviral therapy, and Epigallocatechin gallate (EGCG), a potent adjunctive anti- human immunodeficiency virus (anti-HIV) agent found in green tea. The challenge lies in NFV's low intrinsic dissolution rate, significant p-gp efflux, and high hepatic metabolism, necessitating frequent and high-dose administration. Our objective was to develop a nanoemulsion loaded with NFV and EGCG to enhance oral delivery, expediting antiretroviral effects for NeuroAIDS treatment. After meticulous excipient screening, we selected Tween 40 as the surfactant and polyethylene glycol 400 (PEG 400) as the co-surfactant. Employing a Quality by Design (QbD) approach with statistical multivariate methods, we optimized the nanoemulsion that exhibited a droplet size of 83.21 nm, polydispersity index (PDI) of 2.289, transmittance of 95.20 %, zeta potential of 1.495 mV, pH of 6.95, refractive index of 1.40, viscosity of 24.00 ± 0.42 mPas, and conductivity of 0.162 μS/cm. Pharmacokinetic studies demonstrated superior in vivo absorption of the optimized nanoemulsion compared to NFV and EGCG suspension. The optimized nanoemulsion showcased higher Cmax of NFV (9.75 ± 1.23 μg/ml) and EGCG (27.7 ± 1.22 μg/ml) in the brain, along with NFV (26.44 ± 1.44 μg/ml) and EGCG (313.20 ± 5.53 μg/ml) in the plasma. This study advocates for the potential of NFV and EGCG-loaded nanoemulsion in combination antiretroviral therapy (cART) for effective NeuroAIDS management.

Exploring Drug-Resistant Mutations in Protease Inhibitors and Subtype Distribution Among HIV-1 Positive Patients in Lorestan Province, Iran

: This study focuses on drug-resistant mutations in protease inhibitors (PIs) and the distribution of Human immunodeficiency virus type 1 (HIV-1) subtypes in Lorestan province, Iran. A total of 59 patients were categorized into two groups: Recipients of antiretroviral therapy (ART) and drug-naive individuals. Genotypic resistance testing was performed using nested PCR, followed by sequencing and analysis of the PCR product to identify drug-resistance mutations and determine the viral subtype. Among the ART recipients, 11 (78%) exhibited major mutations, while 3 (22%) had minor mutations specifically in PIs. The most commonly observed major protease inhibitor (PI) mutations were D30N (27.2%) and V32I (27.2%), followed by G48A (18.1%), L90M (18.1%), and L76V (9%). The most frequent minor PI mutations recorded were K20R (40%), L10I (20%), F53I (20%), and V11I (20%). No drug resistance was detected in drug-naive patients. Lopinavir (LPV) and nelfinavir (NFV) exhibited the highest levels of resistance, while saquinavir (SQV) and fosamprenavir (FPV) showed the highest levels of susceptibility. All participants were found to be infected with CRF35_AD, the dominant HIV-1 subtype in Iran. This study represents the first attempt in the region to analyze drug-resistant mutations in PIs among ART-experienced patients in Lorestan province. The findings contribute to ongoing efforts aimed at controlling the spread of drug-resistant HIV-1 strains.

Activity profiling of natural and synthetic SARS-Cov-2 inhibitors using molecular docking analysis

Abstract COVID-19, the global pandemic caused by SARS-Corona virus 2 (SARS-CoV-2), recently ravaged the World with various efforts charged towards finding therapeutic drug targets for this novel virus. The identification of COVID-19 main protease (Mpro) opened the possibility of testing new families of inhibitors as potential anti-coronaviral drugs. Protein-drug interaction is of pivotal importance to understanding the structural features essential for any ligand affinity. This study evaluated the efficacy of an isolated bioactive plant compound and synthetic tetraazamacrocycles against COVID-19 Mpro by molecular docking. Molecular docking investigations were performed using PyRx, Auto Dock vina and Discovery Studio (DS) to analyze the inhibition probability of these compounds against COVID-19. COVID-19 Mpro (PDB ID: 6LU7: Resolution 2.16 Å) was docked with 1 flavonoid and 3 tetraaza-macrocyclic compounds comparatively with known anti-viral drugs (Remdesivir (REMD) and Nelfinavir (NELF)) and hydroxychloroquine (HCQ). Docking studies showed H-TEAD, 5 interacting with 5 residues having the highest binding affinity of −9.4 kcal/mol, followed by TEAD with 5 residue interactions and a binding affinity value of −9.4 kcal/mol, HA-TEAD, 7 has 5 interactions with a binding affinity of −9.3 kcal/mol, and Siam1 has 6 interactions with a binding energy of −7.8 kcal/mol. All the docked potential drugs have binding energies higher than the reference drugs HCQ, 1 and REMD, 2 connoting greater activity except NELF, 3 whose value is only lower than the 3 macrocycles (HA-TEAD, 7 and H-TEAD, 5 and TEA1, 6). They are bound through hydrogen bonds, arene-anion and arene-cation interactions. The trend of binding affinity show H-TEAD (−9.4 kcal/mol) = TEAD1 (−9.4 kcal/mol) > HA-TEAD (−9.3 kcal/mol) > NELF (−8.7 kcal/mol) > Siamone (−8.8 kcal/mol) > HCQ (−7.2 kcal/mol) > REMD (−6.2 kcal/mol) while the number of interactions shows REMD > HA-TEAD = HCQ > Siamone > NELF > H-TEAD > TEAD1. This study, hence, validates the activity of HCQ against COVID-19 and provides a foundation for advanced experimental research, to evaluate the real pharmaceutical potentials of these compounds, towards finding a cure for COVID-19 and other related diseases.

Abstract B016: Repurposing nelfinavir for re-sensitizing platinum-resistant high grade serous ovarian cancer cells

Abstract B016: Repurposing nelfinavir for re-sensitizing platinum-resistant high grade serous ovarian cancer cells

Prediction of Binding Pose and Affinity of Nelfinavir, a SARS-CoV-2 Main Protease Repositioned Drug, by Combining Docking, Molecular Dynamics, and Fragment Molecular Orbital Calculations.

A novel in silico drug design procedure is described targeting the Main protease (Mpro) of the SARS-CoV-2 virus. The procedure combines molecular docking, molecular dynamics (MD), and fragment molecular orbital (FMO) calculations. The binding structure and properties of Mpro were predicted for Nelfinavir (NFV), which had been identified as a candidate compound through drug repositioning, targeting Mpro. Several poses of the Mpro and NFV complexes were generated by docking, from which four docking poses were selected by scoring with FMO energy. Then, each pose was subjected to MD simulation, 100 snapshot structures were sampled from each of the generated MD trajectories, and the structures were evaluated by FMO calculations to rank the pose based on binding energy. Several residues were found to be important in ligand recognition, including Glu47, Asp48, Glu166, Asp187, and Gln189, all of which interacted strongly with NFV. Asn142 is presumably regarded to form hydrogen bonds or CH/π interaction with NFV; however, in the present calculation, their interactions were transient. Moreover, the tert-butyl group of NFV had no interaction with Mpro. Identifying such strong and weak interactions provides candidates for maintaining and substituting ligand functional groups and important suggestions for drug discovery using drug repositioning. Besides the interaction between NFV and the amino acid residues of Mpro, the desolvation effect of the binding pocket also affected the ranking order. A similar procedure of drug design was applied to Lopinavir, and the calculated interaction energy and experimental inhibitory activity value trends were consistent. Our approach provides a new guideline for structure-based drug design starting from a candidate compound whose complex crystal structure has not been obtained.

Results of an Open-Label Phase 1 Study Repurposing Oral Metformin and Nelfinavir in Combination with Subcutaneous Bortezomib in Patients with Relapsed and/or Refractory Multiple Myeloma

Background: GLUT4 inhibition via the use of a protease inhibitor, such as nelfinavir (NEL), is an attractive therapeutic option in multiple myeloma (MM), given the dependence of MM cells on glucose. Furthermore, combining a GLUT4 inhibitor with an oxidative phosphorylation inhibitor, such as metformin (MET), may counter the possibility of therapeutic resistance to GLUT4 inhibition in MM cells, showing synergistic promise (Dalva-Aydemir et al., Clin Can Res 2015). In addition to GLUT4 inhibition, NEL also lowers the cytotoxicity resistance of MM cells against proteasome inhibitors such as bortezomib (BOR) (Driessen et al., Blood 2018). Thus, this study evaluated the safety and tolerability of repurposing MET and NEL, in combination with BOR for the treatment of relapsed/refractory MM (RRMM) that had progressed on all standard of care (SOC) therapies. Methods: This trial utilized a 3+3 dose escalation design with 3 dose levels planned for up to a maximum of six (21-day) cycles. MET was administered for 14/21 days and started at a dose of 500 mg BID with plans to be investigated at a maximum dose of 1000 mg BID. NEL was administered for 14/21 days and started at a dose of 1250 mg BID with plans to be investigated to a maximum dose of 2500 mg BID. SubQ BOR was administered on days 1, 8, and 15 of a 21-day cycle at a dose of 1.3 mg/m 2 to a portion of patients. Patients with RRMM were required to have had 2 prior lines of therapy and prior exposure to proteasome inhibitors (PIs), immunomodulators (IMiDs), and Anti-CD38 monoclonal antibodies. The primary objective was to determine the maximal tolerated dose (MTD) of this combination. The secondary objective was to evaluate the safety as well as the overall response rate (ORR) of this combination. This trial was funded by the Helen Diller Family Foundation. Results: From 4/2019 until 9/2022, nine patients were accrued with a median age of 65 (range: 42-81) that received a median of 7 prior lines of therapy (Range: 6-13). All but one patient had a prior autologous stem cell transplant. Only one patient was not triple-class refractory, and 2/3 rd (n = 6) also had prior anti-BCMA therapy. The first three patients received only MET (500 mg BID) and NEL (1250 mg BID) at the first dose level for up to one cycle before experiencing progressive disease and coming off the study. Given the limited activity of MET and NEL in the initial treatment of these three patients, two subsequent amendments to the protocol allowed for the upfront addition of BOR 1.3 mg/m2 to the original combination, as well as shortened the DLT evaluation period from two cycles to just one. Thus, the following six patients received MET (500 mg BID) and NEL (1250 mg BID) at the first dose level in addition to weekly BOR at 1.3 mg/m2. Four (44%) patients experienced grade 3+ hematological AEs and six (67%) experienced grade 3+ non-hematological AEs. The most common hematologic grade 3+ AE observed was anemia (44%). The nonhematologic grade 3+ AEs observed were dyspnea, fatigue, nausea, and vomiting (11% each). None of the AEs were possibly related to treatment, suggesting good overall safety of the combination. While eight of nine patients have since died of progressive disease, no deaths were attributable to the treatment. All six patients who received BOR upfront with MET and NEL were previously refractory to BOR in prior lines of therapy; however, none had received BOR as their last line of therapy prior to accrual to this study. Four of these six patients had progressive disease after one cycle of therapy and went off study. However, the remaining two were able to receive 2 or more cycles of therapy, with one experiencing an unconfirmed minor response (MR) in the first cycle and the other experiencing stable disease (SD) for all six cycles. The patient who experienced SD was safely able to transition to a subsequent clinical trial utilizing an anti-BCMA bispecific antibody therapy and remains alive at the time of this analysis. The study was closed before accrual to the next dose level was started. Conclusions: This is the first study to evaluate the safety and efficacy of this repurposed drug combination in this very difficult-to-treat population of RRMM. While no ORR was observed, identification of biomarkers used for selection of patients with no other SOC options who could experience at least SD responses may be beneficial in allowing this combination to slow or stabilize the disease progression until other novel therapies or clinical trials are available.

The cytotoxic activity of carfilzomib together with nelfinavir is superior to the bortezomib/nelfinavir combination in non-small cell lung carcinoma

Chemotherapy resistance is still a major problem in the treatment of patients with non-small-cell-lung carcinoma (NSCLC), and novel concepts for the induction of cytotoxicity in NSCLC are highly warranted. Proteotoxicity, the induction of cytotoxicity by targeting the ubiquitin proteasome system, represents an appealing innovative strategy. The combination of the proteasome inhibitor bortezomib (BTZ) and the proteotoxic stress-inducing HIV drug nelfinavir (NFV) synergistically induces proteotoxicity and shows encouraging preclinical efficacy in NSCLC. The second-generation proteasome inhibitor carfilzomib (CFZ) is superior to BTZ and overcomes BTZ resistance in multiple myeloma patients. Here, we show that CFZ together with NFV is superior to the BTZ + NFV combination in inducing endoplasmic reticulum stress and proteotoxicity through the accumulation of excess proteasomal substrate protein in NSCLC in vitro and ex vivo. Interestingly, NFV increases the intracellular availability of CFZ through inhibition of CFZ export from NSCLC cells that express multidrug resistance (MDR) protein. Combining CFZ with NFV may therefore represent a future treatment option for NSCLC, which warrants further investigation.

Meta-Data Analysis to Explore the Hub of the Hub-Genes That Influence SARS-CoV-2 Infections Highlighting Their Pathogenetic Processes and Drugs Repurposing.

The pandemic of SARS-CoV-2 infections is a severe threat to human life and the world economic condition. Although vaccination has reduced the outspread, but still the situation is not under control because of the instability of RNA sequence patterns of SARS-CoV-2, which requires effective drugs. Several studies have suggested that the SARS-CoV-2 infection causing hub differentially expressed genes (Hub-DEGs). However, we observed that there was not any common hub gene (Hub-DEGs) in our analyses. Therefore, it may be difficult to take a common treatment plan against SARS-CoV-2 infections globally. The goal of this study was to examine if more representative Hub-DEGs from published studies by means of hub of Hub-DEGs (hHub-DEGs) and associated potential candidate drugs. In this study, we reviewed 41 articles on transcriptomic data analysis of SARS-CoV-2 and found 370 unique hub genes or studied genes in total. Then, we selected 14 more representative Hub-DEGs (AKT1, APP, CXCL8, EGFR, IL6, INS, JUN, MAPK1, STAT3, TNF, TP53, UBA52, UBC, VEGFA) as hHub-DEGs by their protein-protein interaction analysis. Their associated biological functional processes, transcriptional, and post-transcriptional regulatory factors. Then we detected hHub-DEGs guided top-ranked nine candidate drug agents (Digoxin, Avermectin, Simeprevir, Nelfinavir Mesylate, Proscillaridin, Linifanib, Withaferin, Amuvatinib, Atazanavir) by molecular docking and cross-validation for treatment of SARS-CoV-2 infections. Therefore, the findings of this study could be useful in formulating a common treatment plan against SARS-CoV-2 infections globally.

Molecular modeling identification of potential drug candidates from selected African plants against SARS-CoV-2 key druggable proteins

Coronavirus disease 2019 (COVID-19) pandemic, caused by the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is one of the major health threats the world has experienced. In order to stem the tide of the virus and its associated disease, rapid efforts have been dedicated to identifying credible anti-SARS-CoV-2 drugs. This study forms part of the continuing efforts to develop anti-SARS-CoV-2 molecules and employed a computational structure-activity relationship approach with emphasis on 99 plant secondary metabolites from eight selected African medicinal plants with proven therapeutic benefits against respiratory diseases focusing on the viral protein targets [Spike protein (Sgp), Main protease (Mpro), and RNA-dependent RNA polymerase (RdRp)]. The results of the molecular dynamics simulation of the best docked compounds presented as binding free energy revealed that three compounds each against the Sgp (VBS, COG and ABA), and Mpro (COR, QOR and ABG) had higher and better affinity for the proteins than the respective reference drugs, cefoperazone (CSP) and Nelfinavir (NEF), while four compounds (HDG, VBS, COR and KOR) had higher and favorable binding affinity towards RdRp than the reference standard, ramdesivir (RDS). Analysis of interaction with the receptor binding domain amino acid residues of Sgp showed that VBS had the highest number of interactions (17) relative to 14 and 13 for COG and ABA, respectively. For Mpro, COR showed interactions with catalytic dyad residues (His172 and Cys145). Compared to RDS, COR, HDG, VBS and KOR formed 19, 18, 17 and 12 H-bond and Van der Waal bonds, respectively, with RdRp. Furthermore, structural examination of the three proteins after binding to the lead compounds revealed that the compounds formed stable complexes. These observations suggest that the identified compounds might be beneficial in the fight against COVID-19 and are suggested for further in vitro and in vivo experimental validation.

Abstract 1839: Nelfinavir induced-cytotoxicity towards high-grade serous ovarian cancer cells involves induction of the unfolded protein response, modulation of protein synthesis, DNA damage, lysosomal impairment, and potentiation of toxicity caused by proteasome inhibition

Abstract High-grade serous ovarian cancer (HGSOC) is a significant cause of mortality among women worldwide. Traditional treatment consists of platinum-based therapy; however, the rapid development of platinum resistance contributes to lower life expectancy, warranting newer therapies to supplement the current platinum-based protocol. Repurposing market-available drugs as cancer therapeutics is a cost- and time-effective way to avail new therapies to drug-resistant patients. The anti-HIV agent nelfinavir (NFV) has shown promising toxicity against various cancers; however, its role against HGSOC is unknown. Here, we studied the effect of NFV against HGSOC cells obtained from patients along disease progression and carrying different sensitivities to platinum. NFV triggered, independently of platinum sensitivity, a dose-dependent reduction of HGSOC cell number and viability, and a parallel increase in hypo-diploid DNA content. Moreover, a dose-dependent reduction of clonogenic survival of cells escaping the acute toxicity was indicative of long-term residual damage. Western blot analysis of underlying molecular mechanisms revealed activation by NFV of the three signaling arms of the unfolded protein response (UPR): PERK, IRE1alpha and ATF6 - in a similar manner to the classical endoplasmic reticulum (ER) stressor tunicamycin. NFV-mediated modulation of the UPR was accompanied by the inhibition of global protein synthesis as analyzed through a non-radioactive method by labelling the nascent polypeptides with puromycin. NFV maintained a proapoptotic environment through the UPR, evidenced by a dose- and time-dependent enhanced expression of ATF4, CHOP, increased Bax/Bcl2 ratio, and cleavage of executioner caspase-7. Enhanced gamma-H2AX suggested NFV-mediated induction of DNA damage, which was associated with decreased proliferation signals driven by the AKT and ERK pathways. NFV increased the level of autophagosome-associated protein LC3II in HGSOC cells of varying platinum sensitivities; however, the autophagic flux was not increased during co-treatment with NFV and the lysosomal inhibitor bafilomycin A1, suggesting a likely impairment of the lysosomes by NFV impeding autophagosome clearance. Finally, we show that NFV potentiates the short-term cell cycle arrest and long-term toxicity caused by the proteasome inhibitor bortezomib. Overall, our in vitro study demonstrates that NFV can therapeutically target HGSOC cells of differential platinum sensitivities via several mechanisms, suggesting its prospective repurposing benefit considering its good safety profile. Citation Format: Mahbuba R. Subeha, Alicia A. Goyeneche, Prisca Bustamante, Michael A. Lisio, Julia V. Burnier, Carlos M. Telleria. Nelfinavir induced-cytotoxicity towards high-grade serous ovarian cancer cells involves induction of the unfolded protein response, modulation of protein synthesis, DNA damage, lysosomal impairment, and potentiation of toxicity caused by proteasome inhibition [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1839.

Identification of SARS-CoV-2 inhibitors targeting Mpro and PLpro using in-cell-protease assay

SARS-CoV-2 proteases Mpro and PLpro are promising targets for antiviral drug development. In this study, we present an antiviral screening strategy involving a novel in-cell protease assay, antiviral and biochemical activity assessments, as well as structural determinations for rapid identification of protease inhibitors with low cytotoxicity. We identified eight compounds with anti-SARS-CoV-2 activity from a library of 64 repurposed drugs and modeled at protease active sites by in silico docking. We demonstrate that Sitagliptin and Daclatasvir inhibit PLpro, and MG-101, Lycorine HCl, and Nelfinavir mesylate inhibit Mpro of SARS-CoV-2. The X-ray crystal structure of Mpro in complex with MG-101 shows a covalent bond formation between the inhibitor and the active site Cys145 residue indicating its mechanism of inhibition is by blocking the substrate binding at the active site. Thus, we provide methods for rapid and effective screening and development of inhibitors for blocking virus polyprotein processing as SARS-CoV-2 antivirals. Additionally, we show that the combined inhibition of Mpro and PLpro is more effective in inhibiting SARS-CoV-2 and the delta variant.

Nelfinavir Induces Cytotoxicity towards High-Grade Serous Ovarian Cancer Cells, Involving Induction of the Unfolded Protein Response, Modulation of Protein Synthesis, DNA Damage, Lysosomal Impairment, and Potentiation of Toxicity Caused by Proteasome Inhibition.

Simple SummaryHigh-grade serous ovarian cancer (HGSOC) accounts for 70% of all ovarian-cancer-related deaths. Mainstay treatment with platinum-based drugs following surgery results in favorable outcomes in the majority of patients; however, in >80% of cases, the disease relapses with eventual drug resistance. As such, urgent development of improved alternative therapies is necessary for HGSOC patients with lower life expectancy. Rapid repurposing of market available drugs for cancer therapy is a cost-effective alternative to bypass the decade-long traditional drug development pipeline. Among potential drug-repurposing candidates, nelfinavir (NFV)—an anti-infective agent to treat acquired immunodeficiency syndrome (AIDS)—has shown anti-cancer effects against diverse cancers; however, its remedial benefits against HGSOC are unknown. In this study, we explored how NFV targets HGSOC cells obtained from patients at platinum-sensitive and -resistant stages. We observed beneficial efficacy elicited by NFV against HGSOC in both disease conditions through multiple mechanistic avenues, suggesting positive drug-repurposing prospects.High-grade serous ovarian cancer (HGSOC) is a significant cause of mortality among women worldwide. Traditional treatment consists of platinum-based therapy; however, rapid development of platinum resistance contributes to lower life expectancy, warranting newer therapies to supplement the current platinum-based protocol. Repurposing market-available drugs as cancer therapeutics is a cost- and time-effective way to avail new therapies to drug-resistant patients. The anti-HIV agent nelfinavir (NFV) has shown promising toxicity against various cancers; however, its role against HGSOC is unknown. Here, we studied the effect of NFV against HGSOC cells obtained from patients along disease progression and carrying different sensitivities to platinum. NFV triggered, independently of platinum sensitivity, a dose-dependent reduction in the HGSOC cell number and viability, and a parallel increase in hypo-diploid DNA content. Moreover, a dose-dependent reduction in clonogenic survival of cells escaping the acute toxicity was indicative of long-term residual damage. In addition, dose- and time-dependent phosphorylation of H2AX indicated NFV-mediated DNA damage, which was associated with decreased survival and proliferation signals driven by the AKT and ERK pathways. NFV also mediated a dose-dependent increase in endoplasmic reticulum stress-related molecules associated with long-term inhibition of protein synthesis and concurrent cell death; such events were accompanied by a proapoptotic environment, signaled by increased phospho-eIF2α, ATF4, and CHOP, increased Bax/Bcl-2 ratio, and cleaved executer caspase-7. Finally, we show that NFV potentiates the short-term cell cycle arrest and long-term toxicity caused by the proteasome inhibitor bortezomib. Overall, our in vitro study demonstrates that NFV can therapeutically target HGSOC cells of differential platinum sensitivities via several mechanisms, suggesting its prospective repurposing benefit considering its good safety profile.

Computational Simulation of HIV Protease Inhibitors to the Main Protease (Mpro) of SARS-CoV-2: Implications for COVID-19 Drugs Design.

SARS-CoV-2 is highly homologous to SARS-CoV. To date, the main protease (Mpro) of SARS-CoV-2 is regarded as an important drug target for the treatment of Coronavirus Disease 2019 (COVID-19). Some experiments confirmed that several HIV protease inhibitors present the inhibitory effects on the replication of SARS-CoV-2 by inhibiting Mpro. However, the mechanism of action has still not been studied very clearly. In this work, the interaction mechanism of four HIV protease inhibitors Darunavir (DRV), Lopinavir (LPV), Nelfinavir (NFV), and Ritonavire (RTV) targeting SARS-CoV-2 Mpro was explored by applying docking, molecular dynamics (MD) simulations, and MM–GBSA methods using the broad-spectrum antiviral drug Ribavirin (RBV) as the negative and nonspecific control. Our results revealed that LPV, RTV, and NFV have higher binding affinities with Mpro, and they all interact with catalytic residues His41 and the other two key amino acids Met49 and Met165. Pharmacophore model analysis further revealed that the aromatic ring, hydrogen bond donor, and hydrophobic group are the essential infrastructure of Mpro inhibitors. Overall, this study applied computational simulation methods to study the interaction mechanism of HIV-1 protease inhibitors with SARS-CoV-2 Mpro, and the findings provide useful insights for the development of novel anti-SARS-CoV-2 agents for the treatment of COVID-19.

Decoding molecular mechanism underlying binding of drugs to HIV-1 protease with molecular dynamics simulations and MM-GBSA calculations

ABSTRACT HIV-1 protease (PR) is thought to be efficient targets of anti-AIDS drug design. Molecular dynamics (MD) simulations and multiple post-processing analysis technologies were applied to decipher molecular mechanism underlying binding of three drugs Lopinavir (LPV), Nelfinavir (NFV) and Atazanavir (ATV) to the PR. Binding free energies calculated by molecular mechanics generalized Born surface area (MM-GBSA) suggest that compensation between binding enthalpy and entropy plays a vital role in binding of drugs to PR. Dynamics analyses show that binding of LPV, NFV and ATV highly affects structural flexibility, motion modes and dynamics behaviour of the PR, especially for two flaps. Computational alanine scanning and interaction network analysis verify that although three drugs have structural difference, they share similar binding modes to the PR and common interaction clusters with the PR. The current findings also confirm that residues located interaction clusters, such as Asp25/Asp25ʹ, Gly27/Gly27ʹ, Ala28/Ala28ʹ, Asp29, Ile47/Ile47ʹ, Gly49/Gly49ʹ, Ile50/Ile50ʹ, Val82/Val82ʹ and Ile84/Ile84, can be used as efficient targets of clinically available inhibitors towards the PR.

Патогенез COVID-19

В статье на основании литературных источников представлены современные данные об основных патогенетических особенностях коронавирусной инфекции, связанной с вирусом SARS-CoV-2, вызвавшим в 2019 году, по определению Всемирной организации здравоохранения, пандемию. В литературном обзоре подробно освещены процессы связывания вируса SARS-CoV-2 с рецептором клеток человека, которые экспрессируют ангиотензинпревращающий фермент 2 (АСЕ2), а также интернализация, репликация вируса и высвобождение новых вирионов из инфицированной клетки, которые поражают таргетные органы (легкие, пищеварительный тракт, сердце, центральную нервную систему и почки) и индуцируют развитие местного и системного воспалительного ответа. Описаны существующие способы медикаментозного воздействия, препятствующие инфицированию человека вирусом SARS-CoV-2. Выделены основные эпидемиологические моменты инфицирования вирусом SARS-CoV-2, указывающие на преимущественное поражение пожилых людей и чаще лиц мужского пола в связи с более высоким уровнем экспрессии АСЕ2, в большей степени в альвеолоцитах, чем у лиц женского пола. Продемонстрированы механизмы развития ответной реакции врожденной и адаптивной иммунной системы макроорганизма на инфицирование вирусом SARS-CoV-2. Представлены терапевтические стратегии, связанные с влиянием на различные этапы жизнедеятельности вируса SARS-CoV-2: интернализацию — использование солютабных доменов S-белка, антител против S-белка, одноцепочечного вариабельного фрагмента антител к АСЕ2 или ингибирования гликозилирования клеточных рецепторов, блокирования взаимодействия S-протеина вируса SARS-CoV-2 с протеином ACE2 и подавления интернализации вируса за счет назначения препаратов хлорохин и гидроксихлорохин; репликацию — ингибирование вирусной РНК-зависимой РНК-полимеразой и применение фавипиравира, ненуклеозидного противовирусного препарата триазавирина, антиретровирусных препаратов (лопинавира в сочетании с ритонавиром), нелфинавира, рибавирина, галидесивира, умифеновира, ингибиторов химотрипсиноподобной протеазы (цинансерина, флавоноидов) и папаиноподобной протеазы. Вышеперечисленные терапевтические методы в ближайшем будущем будут направлены на предупреждение развития и лечение как острого респираторного дистресс-синдрома, так и состояний, обусловленных поражением других таргетных органов при COVID-19.

Abstract 1013: Mechanistic role of nelfinavir as drug-repurposing strategy against high-grade serous ovarian cancer

Abstract Platinum-based therapy following tumor-debulking surgery has been the backbone of treatment for high-grade serous ovarian cancer (HGSOC) since the 1970s; however, high recurrence of platinum-resistant disease necessitates the development of improved alternative therapies. Repurposing market-available drugs as cancer therapeutics carries the prospect of reducing the timeframe and cost of drug development, posing potential benefits to drug-resistant as well as financially underprivileged patients. Nelfinavir (NFV), an orally available anti-HIV drug, has shown promising effects against diverse cancers as demonstrated through a myriad of pre-clinical studies and clinical trials; however, its remedial benefits against HGSOC are still unclear. In this study, we explored the therapeutic efficacy of NFV on HGSOC cells generated from patients when platinum sensitive or resistant. Acute drug toxicity was assessed by total cell count, percent viability, and the level of hypo-diploid DNA content following 72 h of treatment with NFV. Living cells that tolerated 72 h of NFV treatment were subjected to further drug-free re-incubation for 14-21 days, to assess the residual anti-clonogenic potential of the drug. NFV triggered a dose-depended reduction of total cell number and viability, with a parallel increased hypo-diploid DNA content in both platinum-sensitive and resistant HGSOC cells. A dose-dependent reduction in the number of colonies - originating from cells that evaded acute toxicity - suggested long-term residual toxicity of NFV. Western blot analysis of underlying molecular mechanisms revealed phosphorylation of γH2AX, which suggested NFV-mediated induction of DNA damage. NFV also inhibited proliferation signals by reducing the phosphorylation of Akt and ERK. Moreover, NFV stimulated endoplasmic reticulum (ER) stress in a dose-dependent manner, which was evident from the enhanced expression of GRP78, IRE1α, ATF4, CHOP, and phosphorylated eIF2α. A time-dependent steady increase of ATF4 and CHOP suggested a progressive temporal apoptotic shift during NFV treatment. Finally, the cleavage of caspases-3 and -7 and their downstream effector PARP, in association with increased pro-apoptotic protein BAX, indicated caspase-associated cell-death during NFV-mediated cytotoxicity. In summary, we demonstrated that HGSOC cells of differential platinum sensitivities could be therapeutically targeted by NFV via multipronged mechanistic approaches, encouraging its prospective repurposing benefit against HGSOC. Citation Format: Mahbuba R. Subeha, Alicia A. Goyeneche, Carlos M. Telleria. Mechanistic role of nelfinavir as drug-repurposing strategy against high-grade serous ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1013.

Virtual Screening of Potential Drug Molecules Against Covid-19 Targets: A Drug Repurposing Approach

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has shattered normal life across the world. This deadly virus displays many variants and has claimed many lives in various countries. Spike protein plays a major role in the transmission and infectivity of this virus. The scientific community is trying hard to reign this virus and save human lives. In this effort, drug repurposing has emerged as a reliable tool to screen FDA-approved drugs. In the present study, we did a virtual screening of 265 FDA-approved drugs against two important covid-19 targets (Non-structural protein & main protease) with PDB IDs 6W4H, 6LU7, and 6W63. A comparative analysis of the best drugs based on docking score, binding energy, and effective hits was done against both targets. Out of 265 molecules, the best 7 molecules showed reliable hits against both targets. Best seven drugs namely Saquinavir, Indinavir, Tenofovir Alafenamide, Ritonavir, Nelfinavir mesylate, Cefiderocol and Plazomicin. Our results suggest that these ligands, in combination or individually, can be taken as novel prospects for developing a drug against SARS CoV-2.

Nelfinavir restricts A549 cell growth by inhibiting STAT3 signaling.

ObjectiveTo investigate the anticancer effect of nelfinavir (NFV) on human A549 cells.MethodsThe inhibitory effects of NFV on the proliferation of human A549 cells were assessed using a MTT assay. Apoptotic cells were observed by fluorescence microscopy following Hoechst 33342 staining. Apoptosis of A549 cells was assessed using Annexin-V/propidium iodide staining and flow cytometry. Expression levels of signal transducer and activator of transcription 3 (STAT3) and p-STAT3 were measured by western blotting. STAT3 RNA silencing was used to investigate the pro-apoptotic mechanism of NFV in A549 cells.ResultsNFV dose-dependently suppressed proliferation of human A549 cells and induced significant apoptosis. Western blotting showed that the antitumor function of NFV might be mediated by STAT3 inhibition. A549 cell apoptosis in response to 20 µM NFV was significantly increased following STAT3 silencing. NFV significantly impeded the expression of the anti-apoptotic proteins Bcl-xL and Bcl-2, by increased the expression of the pro-apoptotic protein Cle-PARP.ConclusionsOur findings highlight STAT3 as a promising therapeutic target. NFV is a novel anti-cancer drug for the treatment of non-small-cell lung cancer.

Identification of Plitidepsin as Potent Inhibitor of SARS-CoV-2-Induced Cytopathic Effect After a Drug Repurposing Screen.

There is an urgent need to identify therapeutics for the treatment of Coronavirus disease 2019 (COVID-19). Although different antivirals are given for the clinical management of SARS-CoV-2 infection, their efficacy is still under evaluation. Here, we have screened existing drugs approved for human use in a variety of diseases, to compare how they counteract SARS-CoV-2-induced cytopathic effect and viral replication in vitro. Among the potential 72 antivirals tested herein that were previously proposed to inhibit SARS-CoV-2 infection, only 18 % had an IC50 below 25 µM or 102 IU/ml. These included plitidepsin, novel cathepsin inhibitors, nelfinavir mesylate hydrate, interferon 2-alpha, interferon-gamma, fenofibrate, camostat along the well-known remdesivir and chloroquine derivatives. Plitidepsin was the only clinically approved drug displaying nanomolar efficacy. Four of these families, including novel cathepsin inhibitors, blocked viral entry in a cell—type specific manner. Since the most effective antivirals usually combine therapies that tackle the virus at different steps of infection, we also assessed several drug combinations. Although no particular synergy was found, inhibitory combinations did not reduce their antiviral activity. Thus, these combinations could decrease the potential emergence of resistant viruses. Antivirals prioritized herein identify novel compounds and their mode of action, while independently replicating the activity of a reduced proportion of drugs which are mostly approved for clinical use. Combinations of these drugs should be tested in animal models to inform the design of fast track clinical trials.

Repurposing drugs and identification of inhibitors of integral proteins (spike protein and main protease) of SARS-CoV-2

The outbreak of Coronavirus infection (COVID-19) has prompted the World Health Organisation (WHO) to declare the outbreak, a Public Health Emergency of International concern. As part of the efforts to discover lead compounds for clinical use, 53 molecules were screened using molecular docking and dynamic simulations (MDS) techniques to identify potential inhibitors of SARS-CoV-2 spike protein (COVID-19 Sgp) and main protease (COVID-19 Mpro) or both. Lopinavir (LPV), nelfinavir (NEF), hydroxychloroquine (HCQ), remdesivir (RDV) and an irreversible inhibitor of SARS-CoV (N3) were used as standard drugs for COVID-19 Mpro, while zafirlukast (ZFK) and cefoperazone (CSP)) as standard drugs for COVID-19 Sgp. After 100 ns of MDS, with reference to standard drugs (N3, −52.463 Kcal/mol, NEF, −51.618 Kcal/mol, RDV, −48.780 Kcal/mol, LPV, −46.788 Kcal/mol, DRV, −33.655 Kcal/mol and HCQ, −21.065 Kcal/mol), five molecules, HCR, GRN, C3G, EGCG, and K7G were predicted to be promising inhibitors of COVID-19 Mpro with binding energies of −53.877 kcal/mol, −50.653 Kcal/mol, −48.600 kcal/mol, −47.798 kcal/mol and −46.902 kcal/mol, respectively. These lead molecules were then docked at receptor-binding domain (RBD) of COVID-19 Sgp to examine their inhibitory effects. C3G, GRN and K7G exhibited higher binding energies of −42.310 kcal/mol, −32.210 kcal/mol, −26.922 kcal/mol than the recorded values for the reference drugs (CSP, −35.509 kcal/mol, ZFK, −24.242 kcal/mol), respectively. The results of the binding energy and structural analyses from this study revealed that C3G, GRN and K7G could serve as potential dual inhibitors of COVID-19 Sgp and COVID-19 Mpro, while HCR and EGCG would be inhibitors of COVID-19 Mpro. Communicated by Ramaswamy H. Sarma