Hydrotalcite–Niclosamide Nanohybrid as OralFormulation towards SARS-CoV-2 Viral Infections

COVID-19 has been affecting millions of individuals worldwide and, thus far, there is no accurate therapeutic strategy. This critical situation necessitates novel formulations for already existing, FDA approved, but poorly absorbable drug candidates, such as niclosamide (NIC), which is of great relevance. In this context, we have rationally designed NIC-loaded hydrotalcite composite nanohybrids, which were further coated with Tween 60 or hydroxypropyl methyl cellulose (HPMC), and characterized them in vitro. The optimized nanohybrids showed particle sizes <300 nm and were orally administrated to rats to determine whether they could retain an optimum plasma therapeutic concentration of NIC that would be effective for treating COVID-19. The pharmacokinetic (PK) results clearly indicated that hydrotalcite-based NIC formulations could be highly potential options for treating the ongoing pandemic and we are on our way to understanding the in vivo anti-viral efficacy sooner. It is worth mentioning that hydrotalcite–NIC nanohybrids maintained a therapeutic NIC level, even above the required IC50 value, after just a single administration in 8–12 h. In conclusion, we were very successfully able to develop a NIC oral formulation by immobilizing with hydrotalcite nanoparticles, which were further coated with Tween 60 or HPMC, in order to enhance their emulsification in the gastrointestinal tract.

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Pyrimidine biosynthesis inhibitors synergize with nucleoside analogs to block SARS-CoV-2 infection

10.1101/2021.06.24.449811 ◽

2021 ◽

Author(s):

David Schultz ◽

Robert Johnson ◽

Kasirajan Ayyanathan ◽

Jesse Miller ◽

Kanupriya Whig ◽

...

Keyword(s):

Antiviral Activity ◽

Viral Infections ◽

Nucleoside Analogs ◽

Pyrimidine Biosynthesis ◽

Live Virus ◽

Drug Candidates ◽

Biosynthesis Inhibitors ◽

Approved Drugs

The ongoing COVID-19 pandemic has highlighted the dearth of approved drugs to treat viral infections, with only ~90 FDA approved drugs against human viral pathogens. To identify drugs that can block SARS-CoV-2 replication, extensive drug screening to repurpose approved drugs is underway. Here, we screened ~18,000 drugs for antiviral activity using live virus infection in human respiratory cells. Dose-response studies validate 122 drugs with antiviral activity and selectivity against SARS-CoV-2. Amongst these drug candidates are 16 nucleoside analogs, the largest category of clinically used antivirals. This included the antiviral Remdesivir approved for use in COVID-19, and the nucleoside Molnupirivir, which is undergoing clinical trials. RNA viruses rely on a high supply of nucleoside triphosphates from the host to efficiently replicate, and we identified a panel of host nucleoside biosynthesis inhibitors as antiviral, and we found that combining pyrimidine biosynthesis inhibitors with antiviral nucleoside analogs synergistically inhibits SARS-CoV-2 infection in vitro and in vivo suggesting a clinical path forward.

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Nanoformulation of Glycyrrhizic acid as a potent antiviral agent against Covid-19

Current Applied Materials ◽

10.2174/2666731201666220114111711 ◽

2022 ◽

Vol 01 ◽

Author(s):

Sayani Ghosh ◽

Prasun Patra

Keyword(s):

Therapeutic Strategy ◽

Glycyrrhizic Acid ◽

Viral Infections ◽

Antiviral Agent ◽

Viral Gene Expression ◽

Viral Gene ◽

Replication Strategy ◽

Increased Activity

Abstract: In many previous studies, it has been found that liquorice plant (Glycyrrhiza glabra) extracts contain more than 300 natural compounds, most of which are triterpenoids and flavonoids, and had shown promising results in clinical studies for treating many microbial and viral infections. Triterpenoids like glycyrrhizic acid have shown anti-SARS-CoV activity in- vitro. Experimentally, certain glycyrrhizic acid derivatives have shown increased activity by many folds against SARS-associated viruses. These compounds can potentially inhibit the replication cycle of SARS-associated viruses by interfering with the viral gene expression or by inhibiting the spike protein expression, which in turn inhibits the adhesion and entry of the virus. Although the therapeutic has shown great antiviral activity in vitro, but in vivo its efficiency deteriorates till it reaches the liver for metabolism. In the current review, we analyze the unique replication strategy of SARS-CoV-2 and glycyrrhizic acid as a potential drug against SARS-CoV-2. We also discuss possible nano-formulations of glycyrrhizic acid for efficient drug delivery in humans, as a potent therapeutic strategy for COVID-19.

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African and Asian Medicinal Plants as a Repository for Prospective Antiviral Metabolites Against HIV-1 and SARS CoV-2: A Mini Review

Frontiers in Pharmacology ◽

10.3389/fphar.2021.703837 ◽

2021 ◽

Vol 12 ◽

Author(s):

Godwin Anywar ◽

Muhammad Akram ◽

Muhammad Amjad Chishti

Keyword(s):

Medicinal Plants ◽

Plant Species ◽

Viral Infections ◽

Antiviral Agents ◽

Natural Compounds ◽

Drug Candidates ◽

Novel Coronavirus ◽

Hiv 1

Introduction: The worldwide burden of viral infections has triggered a resurgence in the search for new and more efficient antiviral drugs. Scientists are also repurposing existing natural compounds such as the antimalarial drug artemisinin from Artemesia annua L. as potential drug candidates for some of the emerging and re-emerging viral infections such as covid-19Aim: The aim of this review was to analyse the existing literature to explore the actual or potential natural antiviral compounds from African and Asian medicinal plants as lead compounds in the drug discovery process.Methods: We searched the literature on African and Asian medicinal plant species as antiviral agents for HIV-1 and the novel coronavirus (SARS-CoV-2) in various databases and search engines such as Web of Science, Google Scholar and PubMed. The search was limited to in vitro, in vivo, and clinical studies and excluded in silico studies.Results: We present 16 plant species with actual or potential antiviral activity against HIV-1 and SARS-CoV-2. These plant species span the continents of Africa and Asia where they are widely used for treating several other ailments.Conclusion: Natural compounds from plants can play a significant role in the clinical management of HIV/AIDS and the covid-19 pandemic. More research needs to be conducted to investigate the potential toxicities of the various compounds and their efficacies in clinical settings.

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Flavonoids as P-gp Inhibitors: A Systematic Review of SARs

Current Medicinal Chemistry ◽

10.2174/0929867325666181001115225 ◽

2019 ◽

Vol 26 (25) ◽

pp. 4799-4831 ◽

Cited By ~ 4

Author(s):

Jiahua Cui ◽

Xiaoyang Liu ◽

Larry M.C. Chow

Keyword(s):

Molecular Mechanisms ◽

Metastatic Cancer ◽

Drug Candidates ◽

Chemical Structures ◽

Transporter Family ◽

Promising Area ◽

New Generation ◽

Nontoxic Inhibitors

P-glycoprotein, also known as ABCB1 in the ABC transporter family, confers the simultaneous resistance of metastatic cancer cells towards various anticancer drugs with different targets and diverse chemical structures. The exploration of safe and specific inhibitors of this pump has always been the pursuit of scientists for the past four decades. Naturally occurring flavonoids as benzopyrone derivatives were recognized as a class of nontoxic inhibitors of P-gp. The recent advent of synthetic flavonoid dimer FD18, as a potent P-gp modulator in reversing multidrug resistance both in vitro and in vivo, specifically targeted the pseudodimeric structure of the drug transporter and represented a new generation of inhibitors with high transporter binding affinity and low toxicity. This review concerned the recent updates on the structure-activity relationships of flavonoids as P-gp inhibitors, the molecular mechanisms of their action and their ability to overcome P-gp-mediated MDR in preclinical studies. It had crucial implications on the discovery of new drug candidates that modulated the efflux of ABC transporters and also provided some clues for the future development in this promising area.

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Current Approaches to Drug Discovery for Chagas Disease: Methodological Advances

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207322666191010144111 ◽

2019 ◽

Vol 22 (8) ◽

pp. 509-520

Author(s):

Cauê B. Scarim ◽

Chung M. Chin

Keyword(s):

Drug Discovery ◽

Chagas Disease ◽

Drug Candidates ◽

Lead Compounds ◽

New Drug ◽

Compound Libraries ◽

Screening Assays ◽

Cruzi Infection

Background: In recent years, there has been an improvement in the in vitro and in vivo methodology for the screening of anti-chagasic compounds. Millions of compounds can now have their activity evaluated (in large compound libraries) by means of high throughput in vitro screening assays. Objective: Current approaches to drug discovery for Chagas disease. Method: This review article examines the contribution of these methodological advances in medicinal chemistry in the last four years, focusing on Trypanosoma cruzi infection, obtained from the PubMed, Web of Science, and Scopus databases. Results: Here, we have shown that the promise is increasing each year for more lead compounds for the development of a new drug against Chagas disease. Conclusion: There is increased optimism among those working with the objective to find new drug candidates for optimal treatments against Chagas disease.

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Role of interleukins in the pathogenesis of pulmonary fibrosis

Cell Death Discovery ◽

10.1038/s41420-021-00437-9 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Yi Xin She ◽

Qing Yang Yu ◽

Xiao Xiao Tang

Keyword(s):

Pulmonary Fibrosis ◽

Therapeutic Strategy ◽

Future Directions ◽

Regulation Mechanisms ◽

Underlying Mechanisms ◽

Multiple Cells ◽

The Relationship

AbstractInterleukins, a group of cytokines participating in inflammation and immune response, are proved to be involved in the formation and development of pulmonary fibrosis. In this article, we reviewed the relationship between interleukins and pulmonary fibrosis from the clinical, animal, as well as cellular levels, and discussed the underlying mechanisms in vivo and in vitro. Despite the effects of interleukin-targeted treatment on experimental pulmonary fibrosis, clinical applications are lacking and unsatisfactory. We conclude that intervening in one type of interleukins with similar functions in IPF may not be enough to stop the development of fibrosis as it involves a complex network of regulation mechanisms. Intervening interleukins combined with other existing therapy or targeting interleukins affecting multiple cells/with different functions at the same time may be one of the future directions. Furthermore, the intervention time is critical as some interleukins play different roles at different stages. Further elucidation on these aspects would provide new perspectives on both the pathogenesis mechanism, as well as the therapeutic strategy and drug development.

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Potential In Vitro Inhibition of Selected Plant Extracts against SARS-CoV-2 Chymotripsin-Like Protease (3CLPro) Activity

Foods ◽

10.3390/foods10071503 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1503

Author(s):

Carla Guijarro-Real ◽

Mariola Plazas ◽

Adrián Rodríguez-Burruezo ◽

Jaime Prohens ◽

Ana Fita

Keyword(s):

Plant Extracts ◽

Curcuma Longa ◽

Hydrolysis Product ◽

Resonance Energy ◽

Significant Inhibition ◽

Main Role ◽

Turmeric Extract ◽

Ic50 Value

Antiviral treatments inhibiting Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) replication may represent a strategy complementary to vaccination to fight the ongoing Coronavirus disease 19 (COVID-19) pandemic. Molecules or extracts inhibiting the SARS-CoV-2 chymotripsin-like protease (3CLPro) could contribute to reducing or suppressing SARS-CoV-2 replication. Using a targeted approach, we identified 17 plant products that are included in current and traditional cuisines as promising inhibitors of SARS-CoV-2 3CLPro activity. Methanolic extracts were evaluated in vitro for inhibition of SARS-CoV-2 3CLPro activity using a quenched fluorescence resonance energy transfer (FRET) assay. Extracts from turmeric (Curcuma longa) rhizomes, mustard (Brassica nigra) seeds, and wall rocket (Diplotaxis erucoides subsp. erucoides) at 500 µg mL−1 displayed significant inhibition of the 3CLPro activity, resulting in residual protease activities of 0.0%, 9.4%, and 14.9%, respectively. Using different extract concentrations, an IC50 value of 15.74 µg mL−1 was calculated for turmeric extract. Commercial curcumin inhibited the 3CLPro activity, but did not fully account for the inhibitory effect of turmeric rhizomes extracts, suggesting that other components of the turmeric extract must also play a main role in inhibiting the 3CLPro activity. Sinigrin, a major glucosinolate present in mustard seeds and wall rocket, did not have relevant 3CLPro inhibitory activity; however, its hydrolysis product allyl isothiocyanate had an IC50 value of 41.43 µg mL−1. The current study identifies plant extracts and molecules that can be of interest in the search for treatments against COVID-19, acting as a basis for future chemical, in vivo, and clinical trials.

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Prrx1 promotes stemness and angiogenesis via activating TGF-β/smad pathway and upregulating proangiogenic factors in glioma

Cell Death and Disease ◽

10.1038/s41419-021-03882-7 ◽

2021 ◽

Vol 12 (6) ◽

Author(s):

Zetao Chen ◽

Yihong Chen ◽

Yan Li ◽

Weidong Lian ◽

Kehong Zheng ◽

...

Keyword(s):

Stem Cells ◽

Therapeutic Strategy ◽

Critical Role ◽

Glioma Stem Cells ◽

Promoter Regions ◽

Aberrant Expression ◽

Smad Pathway ◽

Tgf Β1

AbstractGlioma is one of the most lethal cancers with highly vascularized networks and growing evidences have identified glioma stem cells (GSCs) to account for excessive angiogenesis in glioma. Aberrant expression of paired-related homeobox1 (Prrx1) has been functionally associated with cancer stem cells including GSCs. In this study, Prrx1 was found to be markedly upregulated in glioma specimens and elevated Prrx1 expression was inversely correlated with prognosis of glioma patients. Prrx1 potentiated stemness acquisition in non-stem tumor cells (NSTCs) and stemness maintenance in GSCs, accompanied with increased expression of stemness markers such as SOX2. Prrx1 also promoted glioma angiogenesis by upregulating proangiogenic factors such as VEGF. Consistently, silencing Prrx1 markedly inhibited glioma proliferation, stemness, and angiogenesis in vivo. Using a combination of subcellular proteomics and in vitro analyses, we revealed that Prrx1 directly bound to the promoter regions of TGF-β1 gene, upregulated TGF-β1 expression, and ultimately activated the TGF-β/smad pathway. Silencing TGF-β1 mitigated the malignant behaviors induced by Prrx1. Activation of this pathway cooperates with Prrx1 to upregulate the expression of stemness-related genes and proangiogenic factors. In summary, our findings revealed that Prrx1/TGF-β/smad signal axis exerted a critical role in glioma stemness and angiogeneis. Disrupting the function of this signal axis might represent a new therapeutic strategy in glioma patients.

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Antimalarial drugs—are they beneficial in rheumatic and viral diseases?—considerations in COVID-19 pandemic

Clinical Rheumatology ◽

10.1007/s10067-021-05805-5 ◽

2021 ◽

Author(s):

Bogna Grygiel-Górniak

Keyword(s):

Connective Tissue ◽

Viral Infections ◽

Current Knowledge ◽

Inflammatory Diseases ◽

Antiviral Drugs ◽

In Vivo Studies ◽

Viral Diseases ◽

Cardiac Complications

AbstractThe majority of the medical fraternity is continuously involved in finding new therapeutic schemes, including antimalarial medications (AMDs), which can be useful in combating the 2019-nCoV: coronavirus disease (COVID-19). For many decades, AMDs have been widely used in the treatment of malaria and various other anti-inflammatory diseases, particularly to treat autoimmune disorders of the connective tissue. The review comprises in vitro and in vivo studies, original studies, clinical trials, and consensus reports for the analysis, which were available in medical databases (e.g., PubMed). This manuscript summarizes the current knowledge about chloroquine (CQ)/hydroxychloroquine (HCQ) and shows the difference between their use, activity, recommendation, doses, and adverse effects on two groups of patients: those with rheumatic and viral diseases (including COVID-19). In the case of connective tissue disorders, AMDs are prescribed for a prolonged duration in small doses, and their effect is observed after few weeks, whereas in the case of viral infections, they are prescribed in larger doses for a short duration to achieve a quick saturation effect. In rheumatic diseases, AMDs are well tolerated, and their side effects are rare. However, in some viral diseases, the effect of AMDs is questionable or not so noticeable as suggested during the initial prognosis. They are mainly used as an additive therapy to antiviral drugs, but recent studies have shown that AMDs can diminish the efficacy of some antiviral drugs and may cause respiratory, kidney, liver, and cardiac complications.

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Predicting Absorption-Distribution Properties of Neuroprotective Phosphine-Borane Compounds Using In Silico Modeling and Machine Learning

Molecules ◽

10.3390/molecules26092505 ◽

2021 ◽

Vol 26 (9) ◽

pp. 2505

Author(s):

Raheem Remtulla ◽

Sanjoy Kumar Das ◽

Leonard A. Levin

Keyword(s):

Machine Learning ◽

Neural Networks ◽

In Silico ◽

Disulfide Bonds ◽

Oral Absorption ◽

In Vivo Studies ◽

Drug Candidates ◽

In Silico Methods

Phosphine-borane complexes are novel chemical entities with preclinical efficacy in neuronal and ophthalmic disease models. In vitro and in vivo studies showed that the metabolites of these compounds are capable of cleaving disulfide bonds implicated in the downstream effects of axonal injury. A difficulty in using standard in silico methods for studying these drugs is that most computational tools are not designed for borane-containing compounds. Using in silico and machine learning methodologies, the absorption-distribution properties of these unique compounds were assessed. Features examined with in silico methods included cellular permeability, octanol-water partition coefficient, blood-brain barrier permeability, oral absorption and serum protein binding. The resultant neural networks demonstrated an appropriate level of accuracy and were comparable to existing in silico methodologies. Specifically, they were able to reliably predict pharmacokinetic features of known boron-containing compounds. These methods predicted that phosphine-borane compounds and their metabolites meet the necessary pharmacokinetic features for orally active drug candidates. This study showed that the combination of standard in silico predictive and machine learning models with neural networks is effective in predicting pharmacokinetic features of novel boron-containing compounds as neuroprotective drugs.

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