Role of medicinal plants in HIV/AIDS therapy

Current Challenges With Highly Active Antiretroviral Therapy and New Hope and Horizon With CRISPR-CAS9 Technology for HIV Treatment

Clustered regularly interspaced short palindromic repeats (CRISPR/Cas system) is now the predominant approach for genome editing. Compared to conventional genetic editing methods, CRISPR/Cas technology offers several advantages that were previously unavailable. Key benefits include the ability to simultaneously modify multiple locations, reduced costs, enhanced efficiency, and a more user-friendly design. By directing Cas-mediated DNA cleavage to specific genomic targets and utilizing intrinsic DNA repair processes, this system can produce site-specific gene modifications. This goal is achieved through an RNA-guided procedure. As the most effective gene editing method currently available, the CRISPR/Cas system has proven to be highly valuable in genomic research across a wide range of species since its discovery as a component of the adaptive immune system in bacteria. Its applicability extends to various organisms, making it increasingly prevalent in the medical field, where it shows great promise in investigating viral infections, cancer, and genetic disorders. Furthermore, it enhances our understanding of fundamental genetics. This article outlines the current antiretroviral therapy and its adverse effects but also CRISPR/Cas technology. This review article also discusses its mechanism of action and potential applications in the treatment of HIV/AIDS.

Bird's eye view of natural products for the development of new anti-HIV agents: Understanding from a therapeutic viewpoint

Acquired immune deficiency syndrome (AIDS) is the name used to describe several potentially life-threatening infections and disorders that happen when HIV has severely compromised the immune system. The primary effect of HIV is to decrease host immunity, exposing the host to external pathogens. The development of pharmaceutical drugs that directly cure the infection is crucial because of the current wide-ranging epidemic of HIV. Most therapeutic anti-HIV drugs are nucleosides. However, their high toxicity and potential for drug resistance restrict their use. Many of the most effective clinical drugs used to inhibit HIV, the activation of latent HIV, and AIDS have been obtained from natural sources. This review focuses on potential natural medicinal products for treating and managing HIV and AIDS. Notwithstanding, further clinical research studies are needed to understand the subject and its dynamics.

The role of weak interactions in evaluation of inhibitory potential of Indinavir as an HIV protease inhibitor and its comparison with innovative drug candidates

Designing and employing enzyme inhibitors against viral enzymes is one of the innovative and efficient approaches to treating viral diseases. These inhibitors can disrupt the viral replication cycle by deactivating vital enzymes, thereby curbing the spread of viral infections by reducing their population. So far, inhibitors have been designed, validated, and introduced for these enzymes. In this study, we designed the drug Indinavir and 20 analogs using Hartree-Fock and DFT methods to enhance the design of more potent protease enzyme inhibitors. Frequency calculations were performed at similar computational levels for all examined drugs and their designed analogs, revealing no negative frequencies. The Pharmacokinetics of the inhibitors were assessed, and inhibitors were screened, with those exhibiting minimal toxicity introduced as drug candidates for further evaluation. The best binding mode of Indinavir and the designed drugs at the protein binding site were determined using molecular docking studies. For the IND20 inhibitor with the best binding mode, an energy of -13.03 (kcal/mol) was reported. Finally, molecular dynamics simulations were conducted to evaluate the inhibitory mechanism of the recommended inhibitor on the protease enzyme. The relevant analyses during the simulation period showed that the designed drug IND20 exhibited better performance in inhibiting the HIV-1 protease enzyme compared to Indinavir.

Bioactive Molecules, Ethnomedicinal Uses, Toxicology, and Pharmacology of Peltophorum africanum Sond (Fabaceae): Systematic Review

Plants have long been used to treat serious illnesses in both humans and animals. A significant underappreciated medicinal tree, Peltophorum africanum Sond is utilized by many different ethnic groups to cure a wide range of illnesses. A variety of electronic databases, including ScienceDirect, Scopus, Scielo, Scifinder, PubMed, Web of Science, Medline, and Google Scholar, were used to search the literature on P. africanum, using key words such as uses, survey, pharmacology, antigonococcal, toxicity, phytochemistry and others. Further data was obtained from several scholarly theses, dissertations, and books on general plant sciences, ethnomedicine, and other pertinent ethnobotanical topics. The plant species possess very important pharmacological activities in vitro, which includes antimicrobial, anti-HIV, antioxidant, anticancer, antidiabetic, and other activities. Phytochemically, the plant possesses various classes of compounds, dominated by flavonols, which may well explain its wider range of pharmacological activities. Although the plant is promising anti-HIV activity, the mode of action and safety profiles of the plant also need to be explored as its extracts exerted some degree of mutagenicity. It is also important to further explore its ethnoveterinary use against a plethora of nematodes that infects both wild and domestic animals. Given its potent pharmacological activity, the further in vivo studies need to be explored to ascertain the comprehensive toxicology of the plant species, thereby developing possible medications. The plant species may further be elevated to a potent pharmaceutical product against plethora of infections.

Coumarins and Hesperetin Inhibit Human Respiratory Syncytial Virus Infection

Respiratory syncytial virus (RSV) is one of the most prevalent viruses that causes severe acute lower respiratory tract infections (ALRTIs) in the elderly and young children. There is no specific drug to treat RSV, only a broad-spectrum antiviral, ribavirin, which is only used in critical cases. Our research group is investigating antiviral agents of natural origin, such as coumarins and flavonoids, that may help reduce or prevent RSV infection. The cytotoxic concentrations of coumarins and hesperetin were tested on A549 and HEp-2 cells and used in inhibition tests in which 80% of the cells were viable. The anti-RSV action of the molecules was analyzed in A549 and HEp-2 cells and in HBE cell cultures infected with RSV-luc or rgRSV. We also encapsulated the compounds using β-cyclodextrin to improve the permeability and solubility of the molecules. Esculetin and 4-methyl inhibited rgRSV effectively on A549 and HEp-2 cells after 24 hpi, and when they were encapsulated, coumarin, esculetin, and hesperetin presented inhibition against rgRSV in HBE culture. The coumarins inhibit RSV replication in cell culture and even manage to overcome the mucus barriers of the HBE cultures, and β-cyclodextrin was essential for some of the coumarins to enter the cell and therefore to reach their targets.

Medicinal Plant and Traditional Knowledge-guided Strategies to Combat HIV Persistence

PURPOSE OF REVIEW

 Combination antiretroviral therapy (cART) does not act on latent HIV reservoirs, and no latency-reversing agent (LRA) to date consistently reduces viral reservoirs in humans. In Sub-Saharan Africa and elsewhere, complementary and alternative medicines (CAM) are traditionally used to manage HIV/AIDS, including a subset with LRA properties.

RECENT FINDINGS

Several plants from the Euphorbiaceae and Thymelaeaceae families have been recently documented for traditional HIV/AIDS management and contain LRAs that function through protein kinase C activation. These CAM are increasingly validated in HIV-infected primary cells and humanized mice. Engagement with traditional health practitioners (THPs) which prioritizes data and benefits sharing can improve trust relations, build long-term collaborations, and advance mutual knowledge on these unique CAM. CAM used traditionally for HIV/AIDS management include LRAs already used by humans, but more study and collaboration with THPs are needed to understand their potential to support global cART-free HIV remission and cure efforts.

Anti-Human Immunodeficiency Virus-1 Property of Thai Herbal Extract Kerra™

Kerra™, a Thai traditional herbal medicine derived from the "Tak-Ka-Si-La Scripture" and composed of nine medicinal plants, has demonstrated potential antiviral properties against HIV. This study investigated the inhibitory effects of Kerra™ on HIV-1 reverse transcriptase (RT) and its ability to prevent pseudo-HIV viral infection in HEK293 cells. The results showed that Kerra™ extract achieved a 95.73 ± 4.24% relative inhibition of HIV-1 RT, with an IC50 value of 42.66 ± 8.74 µg/mL. Docking studies revealed that key phytochemicals in Kerra™, such as oleamide, formononetin, and biochanin A, interact with several residues in the RT non-nucleoside binding pocket, contributing to their inhibitory effects. Furthermore, Kerra™ was able to reduce pseudo-HIV infection in HEK293 cells at a concentration of 10 µg/mL, suggesting its potential as a supplementary treatment for HIV.

Role of diosgenin extracted from Helicteres isora L in suppression of HIV-1 replication: An in vitro preclinical study

Background

Diosgenin, an essential sapogenin steroid with significant biological implications, is composed of a hydrophilic sugar moiety intricately linked to a hydrophobic steroid aglycone. While the antiviral properties of diosgenin against numerous RNA viruses have been extensively documented, its potential in combating Human Immunodeficiency Virus infections remains unexplored.

Experimental procedure

This current investigation presents a comprehensive and systematic analysis of extracts derived from the leaves of Helicteres isora, which are notably enriched with diosgenin. Rigorous methodologies, including established chromatographic techniques and Fourier-transform infrared spectroscopy were employed for the characterization of the active diosgenin compound followed by molecular interaction analyses with the key HIV enzymes and mechanistic validation of HIV inhibition.

Key results

The inhibitory effects of extracted diosgenin on the replication of HIV-1 were demonstrated using a permissive cellular system, encompassing two distinct subtypes of HIV-1 strains. Computational analyses involving molecular interactions highlighted the substantial occupancy of critical active site pocket residues within the key HIV-1 proteins by diosgenin. Additionally, the mechanistic underpinnings of diosgenin activity in conjunction with standard controls were elucidated through specialized colorimetric assays, evaluating its impact on HIV-1 Reverse Transcriptase and Integrase enzymes.

Conclusions

To our current state of knowledge, this study represents the inaugural demonstration of the anti-HIV efficacy inherent to diosgenin found in the leaves of Helicteres isora, and can be taken further for drug design and development for the management of HIV infection.

Inhibition of Cysteine Proteases via Thiol-Michael Addition Explains the Anti-SARS-CoV-2 and Bioactive Properties of Arteannuin B

Artemisia annua is the plant that produces artemisinin, an endoperoxide-containing sesquiterpenoid used for the treatment of malaria. A. annua extracts, which contain other bioactive compounds, have been used to treat other diseases, including cancer and COVID-19, the disease caused by the virus SARS-CoV-2. In this study, a methyl ester derivative of arteannuin B was isolated when A. annua leaves were extracted with a 1:1 mixture of methanol and dichloromethane. This methyl ester was thought to be formed from the reaction between arteannuin B and the extracting solvent, which was supported by the fact that arteannuin B underwent 1,2-addition when it was dissolved in deuteromethanol. In contrast, in the presence of N-acetylcysteine methyl ester, a 1,4-addition (thiol-Michael reaction) occurred. Arteannuin B hindered the activity of the SARS CoV-2 main protease (nonstructural protein 5, NSP5), a cysteine protease, through time-dependent inhibition. The active site cysteine residue of NSP5 (cysteine-145) formed a covalent bond with arteannuin B as determined by mass spectrometry. In order to determine whether cysteine adduction by arteannuin B can inhibit the development of cancer cells, similar experiments were performed with caspase-8, the cysteine protease enzyme overexpressed in glioblastoma. Time-dependent inhibition and cysteine adduction assays suggested arteannuin B inhibits caspase-8 and adducts to the active site cysteine residue (cysteine-360), respectively. Overall, these results enhance our understanding of how A. annua possesses antiviral and cytotoxic activities.

Plant Toxic Proteins: Their Biological Activities, Mechanism of Action and Removal Strategies

Plants evolve to synthesize various natural metabolites to protect themselves against threats, such as insects, predators, microorganisms, and environmental conditions (such as temperature, pH, humidity, salt, and drought). Plant-derived toxic proteins are often secondary metabolites generated by plants. These proteins, including ribosome-inactivating proteins, lectins, protease inhibitors, α-amylase inhibitors, canatoxin-like proteins and ureases, arcelins, antimicrobial peptides, and pore-forming toxins, are found in different plant parts, such as the roots, tubers, stems, fruits, buds, and foliage. Several investigations have been conducted to explore the potential applications of these plant proteins by analyzing their toxic effects and modes of action. In biomedical applications, such as crop protection, drug development, cancer therapy, and genetic engineering, toxic plant proteins have been utilized as potentially useful instruments due to their biological activities. However, these noxious metabolites can be detrimental to human health and cause problems when consumed in high amounts. This review focuses on different plant toxic proteins, their biological activities, and their mechanisms of action. Furthermore, possible usage and removal strategies for these proteins are discussed.

Spherical PEG/SiO2 promising agents for Lamivudine antiviral drug delivery, a molecular dynamics simulation study

Spherical nanocarriers can lead to a bright future to lessen problems of virus infected people. Spherical polyethylene glycol (PEG) and spherical silica (SiO₂) are novel attractive nanocarriers as drug delivery agents, especially they are recently noticed to be reliable for antiviral drugs like anti-HIV, anti-covid-19, etc. Lamivudine (3TC) is used as a first line drug for antiviral therapy and the atomic view of 3TC-PEG/SiO₂ complexes enable scientist to help improve treatment of patients with viral diseases. This study investigates the interactions of 3TC with Spherical PEG/SiO₂, using molecular dynamics simulations. The mechanism of adsorption, the stability of systems and the drug concentration effect are evaluated by analyzing the root mean square deviation, the solvent accessible surface area, the radius of gyration, the number of hydrogen bonds, the radial distribution function, and Van der Waals energy. Analyzed data show that the compression of 3TC is less on PEG and so the stability is higher than SiO₂; the position and intensity of the RDF peaks approve this stronger binding of 3TC to PEG as well. Our studies show that PEG and also SiO₂ are suitable for loading high drug concentrations and maintaining their stability; therefore, spherical PEG/SiO₂ can reduce drug dosage efficiently.

Tackling the Future Pandemics: Broad-Spectrum Antiviral Agents (BSAAs) Based on A-Type Proanthocyanidins

A-type proanthocyanidins (PAC-As) are plant-derived natural polyphenols that occur as oligomers or polymers of flavan-3-ol monomers, such as (+)-catechin and (-)-epicatechin, connected through an unusual double A linkage. PAC-As are present in leaves, seeds, flowers, bark, and fruits of many plants, and are thought to exert protective natural roles against microbial pathogens, insects, and herbivores. Consequently, when tested in isolation, PAC-As have shown several biological effects, through antioxidant, antibacterial, immunomodulatory, and antiviral activities. PAC-As have been observed in fact to inhibit replication of many different human viruses, and both enveloped and non-enveloped DNA and RNA viruses proved sensible to their inhibitory effect. Mechanistic studies revealed that PAC-As cause reduction of infectivity of viral particles they come in contact with, as a result of their propensity to interact with virion surface capsid proteins or envelope glycoproteins essential for viral attachment and entry. As viral infections and new virus outbreaks are a major public health concern, development of effective Broad-Spectrum Antiviral Agents (BSAAs) that can be rapidly deployable even against future emerging viruses is an urgent priority. This review summarizes the antiviral activities and mechanism of action of PAC-As, and their potential to be deployed as BSAAs against present and future viral infections.

Exploration of Anti-HIV Phytocompounds against SARS-CoV-2 Main Protease: Structure-Based Screening, Molecular Simulation, ADME Analysis and Conceptual DFT Studies

The ever-expanding pandemic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has gained attention as COVID-19 and caused an emergency in public health to an unmatched level to date. However, the treatments used are the only options; currently, no effective and licensed medications are available to combat disease transmission, necessitating further research. In the present study, an in silico-based virtual screening of anti-HIV bioactive compounds from medicinal plants was carried out through molecular docking against the main protease (Mpro) (PDB: 6LU7) of SARS-CoV-2, which is a key enzyme responsible for virus replication. A total of 16 anti-HIV compounds were found to have a binding affinity greater than -8.9 kcal/mol out of 150 compounds screened. Pseudohypericin had a high affinity with the energy of -10.2 kcal/mol, demonstrating amino acid residual interactions with LEU141, GLU166, ARG188, and GLN192, followed by Hypericin (-10.1 kcal/mol). Moreover, the ADME (Absorption, Distribution, Metabolism and Excretion) analysis of Pseudohypericin and Hypericin recorded a low bioavailability (BA) score of 0.17 and violated Lipinski's rule of drug-likeness. The docking and molecular simulations indicated that the quinone compound, Pseudohypericin, could be tested in vitro and in vivo as potent molecules against COVID-19 disease prior to clinical trials.This was also supported by the theoretical and computational studies conducted. The global and local descriptors, which are the underpinnings of Conceptual Density FunctionalTheory (CDFT) have beenpredicted through successful model chemistry, hoping that they could be of help in the comprehension of the chemical reactivity properties of the molecular systems considered in this study.

Artemisia Extracts and Artemisinin-Based Antimalarials for COVID-19 Management: Could These Be Effective Antivirals for COVID-19 Treatment?

As the world desperately searches for ways to treat the coronavirus disease 2019 (COVID-19) pandemic, a growing number of people are turning to herbal remedies. The Artemisia species, such as A. annua and A. afra, in particular, exhibit positive effects against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection and COVID-19 related symptoms. A. annua is a source of artemisinin, which is active against malaria, and also exhibits potential for other diseases. This has increased interest in artemisinin's potential for drug repurposing. Artemisinin-based combination therapies, so-called ACTs, have already been recognized as first-line treatments against malaria. Artemisia extract, as well as ACTs, have demonstrated inhibition of SARS-CoV-2. Artemisinin and its derivatives have also shown anti-inflammatory effects, including inhibition of interleukin-6 (IL-6) that plays a key role in the development of severe COVID-19. There is now sufficient evidence in the literature to suggest the effectiveness of Artemisia, its constituents and/or artemisinin derivatives, to fight against the SARS-CoV-2 infection by inhibiting its invasion, and replication, as well as reducing oxidative stress and inflammation, and mitigating lung damage.

Repositioning therapeutics for SARS-CoV-2: Virtual screening of plant-based Anti-HIV compounds as possible inhibitors against COVID-19 viral RdRp

Background:

Coronavirus disease 2019 (COVID-19) has caused a global pandemic with a high mortality rate and infecting people worldwide. The COVID-19 vaccines that are currently in development or already approved are expected to provide at least some protection against the emerging variants of the virus but the mutations may reduce the efficacy of the existing vaccines. Purified phytochemicals from medicinal plants provide a helpful framework for discovering new therapeutic leads as they have long been employed in traditional medicine to treat many disorders.

Objective:

The objectives of the study are to exploit the anti-HIV bioactive compounds against SARS-CoV-2 RNA-dependent RNA polymerase (RdRp) through molecular docking studies and perform the Absorption, Distribution, Metabolism, Excretion and Toxicity (ADMET) properties of potential compounds.

Methods:

Molecular docking was performed to study the interaction of ligands with the target sites of RdRp protein (PDB: 6M71) using AutoDock Vina. The ADMET properties of potential compounds were predicted using the pkCSM platform.

Results:

A total of 151 phytochemicals derived from the medicinal plants with recognized antiviral activity and 18 anti-HIV drugs were virtually screened against COVID-19 viral RdRp to identify putative inhibitors that facilitate the development of potential anti-COVID-19 drug candidates. The computational studies identified 34 compounds and three drugs inhibiting viral RdRp with binding energies ranging from -10.2 to -8.5 kcal/ mol. Among these, five compounds, namely Michellamine B, Quercetin 3-O-(2'',6''-digalloyl)-beta-D-galactopyranoside, Corilagin, Hypericin, and 1,2,3,4,6-Penta-O-galloyl-beta-D-glucose residues bound efficiently with the binding site of RdRp. Besides, Lopinavir, Maraviroc, and Remdesivir drugs also inhibited SARS-CoV-2 polymerase. In addition, the ADMET properties of top potential compounds were also predicted in comparison to the drugs.

Conclusion:

The present study suggested that these potential drug candidates can be further subjected to in vitro and in vivo studies that may help develop effective anti-COVID-19 drugs.

The Decline and Fall of Materia Medica and the Rise of Pharmacology and Therapeutics in Veterinary Medicine

Materia Medica is a Latin term, relating to the history of pharmacy. It describes the sources (vegetable, animal and mineral), nature, preparation, and properties of substances or mixtures of substances, which were used as remedies for the treatment of diseases. Bourgelat authored the first veterinary Materia Medica book. This review describes the evolution and ultimate downfall of Materia Medica concepts and practices. Its survival for more than two millennia reflected the impact of religion and dogmas on therapy. The consignment of Materia Medica to history was signified by publication of the first modern book of veterinary pharmacology and therapeutics by Meyer Jones in 1953. Previously, the dominance of Materia Medica was linked to an hippiatry culture, which was shared with farriers and quacks. The Pasteurian and pharmacological revolutions of the second half of the nineteenth century led to its gradual abandonment. This review explains why the existence of authentically active substances, such as opioid analgesics, cardiotonics and general anesthetics either were not used for those actions or were badly prescribed, in part because of historical precedence and in part from lack of pathophysiological knowledge to justify rational use. The modern concept of dosage, in particular inter-species differences, was not understood. There were also major dogmas, supporting false indications, such as failure to recognize pain as a symptom to be treated, whereas inflammation was only a disease symptom involving excess of activity of the blood system, which had to be vigorously addressed by bleeding and purging. This review covers a well-defined period, ranging from Bourgelat, who wrote the first book of Materia Medica for veterinary studies to the first edition of Meyer Jones textbook in 1953, which marked the end of Materia Medica and the beginning of pharmacology in veterinary medicine.

Pharmacological perspectives and molecular mechanisms of coumarin derivatives against virus disease

Infections caused by viruses are one of the foremost causes of morbidity and mortality in the world. Although a number of antiviral drugs are currently used for treatment of various kinds of viral infection diseases, there is still no available therapeutic agent for most of the viruses in clinical practice. Coumarin is a chemical compound which is found naturally in a variety of plants, it can also be synthetically produced possessing diverse biological effects. More recently, reports have highlighted the potential role of coumarin derivatives as antiviral agents. This review outlines the advances in coumarin-based compounds against various viruses including human immunodeficiency virus, hepatitis virus, herpes simplex virus, Chikungunya virus and Enterovirus 71, as well as the structure activity relationship and the possible mechanism of action of the most potent coumarin derivatives.

Identification of immune features of HIV-infected patients with antiretroviral therapy through bioinformatics analysis

BACKGROUND

Acquired immunodeficiency syndrome (AIDS) is a disease arising from human immunodeficiency virus (HIV). Antiretroviral therapy (ART) is a main therapeutic regimen for inhibiting HIV proliferation and viability. Identification of differentially expressed genes (DEGs) in HIV-infected patients with and without ART could provide theoretical evidence for deep research into the efficacy of ART and corresponding mechanism.

METHODS

In this study, mRNA microarray data (GSE108296) of HIV-infected patients who received and didn't receive ART were downloaded from Gene Expression Omnibus (GEO) database. DEGs were obtained through differential analysis with R package limma. Then, protein-protein interaction (PPI) analysis was performed to identify hub genes and functional modules. Besides, immune-related DEGs were screened, followed by GO annotation and KEGG pathway enrichment analysis. Moreover, various immune cells and immune functions in samples were analyzed by ESTIMATE, ssGSEA and CIBERSORT, based on which the immune function of HIV-infected patients who received and didn't receive ART was evaluated.

RESULTS

A total of 109 DEGs were obtained from differential analysis. Among them, 19 immune-related DEGs were identified and subjected to GO and KEGG enrichment analyses. Furthermore, PPI network analysis was undertaken on the 109 DEGs. 10 hub genes and 3 functional modules were further screened. It was shown that these genes and functional modules were correlated with immune functions and relevant signaling pathways. ESTIMATE, ssGSEA and CIBERSORT results displayed that HIV-infected patients with ART presented a relatively high immune level.

CONCLUSION

According to bioinformatics analysis, we reasonably posited that HIV-infected patients who received ART had an increased immune level relative to patients who didn't receive ART.

Curcumin Nanoparticles as Promising Therapeutic Agents for Drug Targets

Curcuma longa is very well-known medicinal plant not only in the Asian hemisphere but also known across the globe for its therapeutic and medicinal benefits. The active moiety of Curcuma longa is curcumin and has gained importance in various treatments of various disorders such as antibacterial, antiprotozoal, cancer, obesity, diabetics and wound healing applications. Several techniques had been exploited as reported by researchers for increasing the therapeutic potential and its pharmacological activity. Here, the dictum is the new room for the development of physicochemical, as well as biological, studies for the efficacy in target specificity. Here, we discussed nanoformulation techniques, which lend support to upgrade the characters to the curcumin such as enhancing bioavailability, increasing solubility, modifying metabolisms, and target specificity, prolonged circulation, enhanced permeation. Our manuscript tried to seek the attention of the researcher by framing some solutions of some existing troubleshoots of this bioactive component for enhanced applications and making the formulations feasible at an industrial production scale. This manuscript focuses on recent inventions as well, which can further be implemented at the community level.

Anti-Viral and Immunomodulatory Properties of Propolis: Chemical Diversity, Pharmacological Properties, Preclinical and Clinical Applications, and In Silico Potential against SARS-CoV-2

Propolis, a resin produced by honeybees, has long been used as a dietary supplement and folk remedy, and more recent preclinical investigations have demonstrated a large spectrum of potential therapeutic bioactivities, including antioxidant, antibacterial, anti-inflammatory, neuroprotective, immunomodulatory, anticancer, and antiviral properties. As an antiviral agent, propolis and various constituents have shown promising preclinical efficacy against adenoviruses, influenza viruses, respiratory tract viruses, herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2), human immunodeficiency virus (HIV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Over 300 chemical components have been identified in propolis, including terpenes, flavonoids, and phenolic acids, with the specific constituent profile varying widely according to geographic origin and regional flora. Propolis and its constituents have demonstrated potential efficacy against SARS-CoV-2 by modulating multiple pathogenic and antiviral pathways. Molecular docking studies have demonstrated high binding affinities of propolis derivatives to multiple SARS-CoV-2 proteins, including 3C-like protease (3CLpro), papain-like protease (PLpro), RNA-dependent RNA polymerase (RdRp), the receptor-binding domain (RBD) of the spike protein (S-protein), and helicase (NSP13), as well as to the viral target angiotensin-converting enzyme 2 (ACE2). Among these compounds, retusapurpurin A has shown high affinity to 3CLpro (ΔG = -9.4 kcal/mol), RdRp (-7.5), RBD (-7.2), NSP13 (-9.4), and ACE2 (-10.4) and potent inhibition of viral entry by forming hydrogen bonds with amino acid residues within viral and human target proteins. In addition, propolis-derived baccharin demonstrated even higher binding affinity towards PLpro (-8.2 kcal/mol). Measures of drug-likeness parameters, including metabolism, distribution, absorption, excretion, and toxicity (ADMET) characteristics, also support the potential of propolis as an effective agent to combat COVID-19.

Anti-HIV and Anti-Candidal Effects of Methanolic Extract from Heteropterys brachiata

Nowadays, the HIV pandemic is far from controlled. HIV+/AIDS patients show a serious risk of developing resistance to HIV antiretroviral drugs and to be orally colonized by albicans and non-albicans Candida strains resistant to antifungals. As a consequence, new drugs that possess anti-candidal and anti-HIV effects would represent an alternative in the comprehensive treatment of HIV+/AIDS patients. The present study evaluates the possible anti-HIV and anti-Candida effects of a methanolic extract from Heteropterys brachiata (Hb MeOH), an American tropical plant. The anti-HIV effect of Hb MeOH was tested using a non-radioactive colorimetric method (Lenti RT® Activity Assay; Cavidi Tech) that uses reverse transcriptase of HIV-1 enzyme as enzymatic target. The anti-candidal effect of HbMeOH extract was evaluated by following a standardized test protocol of microdilution for yeast using the Candida albicans strain ATCC® 90028. The Hb MeOH at 1 mg/mL concentration shows 38.5% RT-HIV inhibition, while Hb MeOH at 10 mg/mL concentration produced 98% C. albicans growth inhibition. Our findings show that the Hb MeOH possesses a strong anti-candidal activity and moderate anti-HIV effect and suggests that the plant extract could be considered as a potential candidate for HIV/AIDS treatment.

Therapeutic Promises of Medicinal Plants in Bangladesh and Their Bioactive Compounds against Ulcers and Inflammatory Diseases

When functioning properly, the stomach is the center of both physical and mental satisfaction. Gastrointestinal disorders, or malfunctioning of the stomach, due to infections caused by various biological entities and physiochemical abnormalities, are now widespread, with most of the diseases being inflammatory, which, depending on the position and degree of inflammation, have different names such as peptic or gastric ulcers, irritable bowel diseases, ulcerative colitis, and so on. While many synthetic drugs, such as non-steroidal anti-inflammatory drugs, are now extensively used to treat these diseases, their harmful and long-term side effects cannot be ignored. To treat these diseases safely and successfully, different potent medicinal plants and their active components are considered game-changers. In consideration of this, the present review aimed to reveal a general and comprehensive updated overview of the anti-ulcer and anti-inflammatory activities of medicinal plants. To emphasize the efficacy of the medicinal plants, various bioactive compounds from the plant extract, their experimental animal models, and clinical trials are depicted.

Effect of Azadirachta indica and Senna siamea Decoction on CD4+ and CD8+ Level, Toxicological, and Antioxidant Profile in HIV/AIDS Positive Persons

Acquired immune deficiency syndrome (AIDS) is a major public health problem affecting several countries with predominance in black Africa. Faced with therapeutic failure caused by resistance and supply disruptions, searching for other antiretroviral agents, in particular from natural sources, becomes necessary. Given popular consumption of Azadirachta indica and Senna siamea decoction in the Northern Cameroon region and the traditionally attributed antiretroviral value, information on its efficacy and safety consumption is relevant to confirm its use. A total of 297 participants aged 18-52 and HIV-positive were recruited and divided into 3 groups: one taking only the decoction (group 1), another taking only antiretroviral therapy (ARTs) (group 2), and finally, one taking the decoction and antiretroviral (group 3). During 6 months, all the participants of the concerned groups consumed daily (morning and evening) 250 mL of Azadirachta indica and Senna siamea decoction. CD4+ and CD8+ levels were measured by flow cytometry. Hepatic and renal toxicity and oxidative stress were evaluated spectrophotometrically by measuring ALT, AST, ALP, BUN, CREAT, SOD, CAT, and GSH parameters. We note an increase in the CD4+ level of the three groups with values much more pronounced in the group treated by ARTs + decoction, from 328 ± 106 to 752 ± 140. Group 2 presented not only biological signs of hepatic and renal toxicity but also significant oxidative stress. No signs of toxicity were detected in the other groups. The study concludes that a decoction of Azadirachta indica and Senna siamea stimulates the production of CD4+ and is not toxic. On the contrary, it would reduce the toxicity caused by ARTs intake.

Optimization of Light Intensity, Temperature, and Nutrients to Enhance the Bioactive Content of Hyperforin and Rutin in St. John's Wort

St. John’s wort (Hypericum perforatum L.) is a medicinal plant that alleviates depression and other disorders due to its abundance of active ingredients. Hyperforin, rutin, and melatonin are the main active, and important, ingredients in St. John’s wort that alleviate depression. In order to investigate the optimal conditions for accumulating these active ingredients, design of experiments and response surface methodology (RSM) was employed in this study. Two-month-old St John’s wort plants were cultivated in growth chambers at varying temperatures, light intensities, and nutrient solution concentrations before analysis by HPLC, for determining differences in hyperforin, rutin, and melatonin content. The results showed that hyperforin and rutin contents were significantly influenced by temperature (18–23 °C) and light intensity (49–147 μmol m⁻² s⁻¹ photosynthetic photon flux density (PPFD)), whereas Hoagland’s nutrient solution concentration (25–75%) had little effect. The accumulation of melatonin might not be influenced by cultivation conditions. Light intensity and temperature are easily controlled environmental factors in artificial cultivation, both of which are related to secondary metabolite production in the plant. Based on RSM, the optimal conditions for the accumulation of hyperforin and rutin were obtained. The maximum content of hyperforin was 5.6 mg/g, obtained at a temperature of 19 °C, a nutrient solution concentration of 45%, and a light intensity of 49 μmol m⁻² s⁻¹ PPFD. The maximum content of rutin was 3.8 mg/g obtained at a temperature of 18 °C, a nutrient solution concentration of 50%, and a light intensity of 147 μmol m⁻² s⁻¹ PPFD. This evaluation of suitable conditions for the accumulation of bioactive compounds in St. John’s wort can be applied to plant factories on a large scale.

Scientific basis for the industrialization of traditionally used plants of the Rosaceae family

Plants have been traditionally used for the treatment of different types of illness, due to biomolecules with recognised benefits. Rosaceae family is used in traditional Galician medicine. The following plants Agrimonia eupatoria, Crataegus monogyna, Filipendula ulmaria, Geum urbanum, Potentilla erecta and Rosa canina are usually found in treatments. The aim of this study is to perform an ethnobotanical review about the bioactive compounds of these plants and their different bioactivities, both studied in vitro and in vivo. The nature of the bioactive compounds is varied, highlighting the presence of different phenolic compounds, such as phenolic acids, flavonoids or tannins. Understanding the beneficial effects of the administration of the whole plant or target tissues from A. eupatoria, C. monogyna, F. ulmaria, G. urbanum, P. erecta and R. canina as well as those from their individual compounds could lead to the development of new drugs based on the use of natural ingredients.

Coumarin: An emerging antiviral agent

Viral infections are responsible for many illnesses, and recent outbreaks have raised public health concerns. Despite the availability of many antiviral drugs, they are often unsuccessful due to the generation of viral mutants and less effective against their target virus. Identifying novel antiviral drugs is therefore of critical importance and natural products are an excellent source for such discoveries. Coumarin is one such natural compound that is a potential drug candidate owing to its properties of stability, solubility, and low toxicity. There are numerous evidences showing its inhibitory role against infection of various viruses such as HIV, Influenza, Enterovirus 71 (EV71) and coxsackievirus A16 (CVA16). The mechanisms involve either inhibition of proteins essential for viral entry, replication and infection or regulation of cellular pathways such as Akt-Mtor (mammalian target of rapamycin), NF-κB (nuclear factor kappa-light-chain-enhancer of activated B cells), and anti-oxidative pathway including NrF-2 (The nuclear factor erythroid 2 (NFE2)-related factor 2). This review summarizes the present state of understanding with a focus on coumarin's antiviral effect and their possible molecular mechanisms against Influenza virus, HIV, Hepatitis virus, Dengue virus and Chikungunya virus.