Viral protein R inhibitors from Swertia chirata of Myanmar

In silico investigation of binding propensity of hematoxylin derivative and damnacanthal for their potential inhibitory effect on HIV-1 Vpr from different subtypes

HIV-1, the causative agent of AIDS leads to many deaths worldwide though few options are available as therapeutics. To deal with the continuous mutation in the virus genome, requirement of new drugs is always there. Subtype variation plays a crucial role in case of HIV-1 therapeutics development. In this study, we want to investigate some pre examined molecules that can be effective for HIV-1 VPR. Inhibition of several protein-protein interactions with the small molecules will lead to identify some molecules as therapeutics other than the conventional drugs. We retrieved the sequences of different subtypes from the database and representative sequences were identified. Representative structures were modelled and validated using MD simulations. Forty molecules, showing anti Vpr activity in vitro were identified from literature survey and those were docked with each subtype representative structures. Two molecules a stable Hematoxylin Derivative (SHD) and Damnacanthal (D3), these were shown to be bind more effectively for all the subtypes. The stability of the protein and those two small molecule complexes were identified again with MD simulation followed by the binding energy calculation. Thus, these molecules can be thought as any option other than the conventional drug targeting HIV-1 Vpr.Communicated by Ramaswamy H. Sarma.

Swertia chirayita: A comprehensive review on traditional uses, phytochemistry, quality assessment and pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Swertia chirayita (Roxb.) H. Karst. is a traditionally used, well-recognized medicinal plant of the family Gentianaceae with significant therapeutic potential. It has been traditionally used to cure various ailments such as fever, vomiting, jaundice, digestive disorders, heart diseases, diabetes, malaria, scorpion bite, and skin diseases.

AIM OF REVIEW

The present review emphasized the traditional uses, phytochemistry, pharmacology, toxicology, chemical profiling, and structural identification of isolated compounds by analytical and spectroscopic techniques. This review demonstrates the possibility of advanced ethnopharmacological research.

MATERIALS AND METHODS

The literature on S. chirayita was obtained from bibliographic databases like Web of Science, PubMed, Science-Direct, American Chemical Society (ACS), Google Scholar, and SciFinder. The compiled review is covered up until March 2022.

RESULTS

Approximately, 123 specialized metabolites including xanthones, seco-iridoids, terpenoids, alkaloids, and flavonoids have been isolated and characterized from S. chirayita. The extract and isolated compounds exhibited a wide spectrum of pharmacological effects such as anti-inflammatory, antioxidant, antitumor, hepatoprotective, antiviral, antimalarial, and antibacterial offering scientific evidence for traditional claims of this medicinal plant. In addition, various analytical methods using HPTLC, UPLC, HPLC, LC-MS, and GC-MS have also been documented to determine the phytochemicals of S. chirayita.

CONCLUSION

The current article provides information on traditional usage, phytochemistry, chemical profiling, structure elucidation, pharmacological efficacy, toxicity, and future prospects of S. chirayita. This plant has long been traditionally used in a variety of ways by indigenous people. Numerous phytoconstituents and several pharmacological activities have been reported in S. chirayita. However, there are still some scientific gaps such as identification of bioactive compounds, structure-activity relationship and mechanistic action of isolated bioactive compounds, development of effective analytical methods for comprehensive quality control, and safety profiles that need to be addressed.

A Novel Class of HIV-1 Inhibitors Targeting the Vpr-Induced G2-Arrest in Macrophages by New Yeast- and Cell-Based High-Throughput Screening

The human immunodeficiency virus type 1 (HIV-1) accessory protein, Vpr, arrests the cell cycle of the G2 phase, and this Vpr-mediated G2 arrest is implicated in an efficient HIV-1 spread in monocyte-derived macrophages. Here, we screened new candidates for Vpr-targeting HIV-1 inhibitors by using fission yeast- and mammalian cell-based high-throughput screening. First, fission yeast strains expressing the HIV-1 Vpr protein were generated and then treated for 48 h with 20 μM of a synthetic library, including 140,000 chemical compounds. We identified 268 compounds that recovered the growth of Vpr-overexpressing yeast. The selected compounds were then tested in mammalian cells, and those displaying high cytotoxicity were excluded from further cell cycle analysis and imaging-based screening. A flow cytometry analysis confirmed that seven compounds recovered from the Vpr-induced G2 arrest. The cell toxicity and inhibitory effect of HIV-1 replication in human monocyte-derived macrophages (MDM) were examined, and three independent structural compounds, VTD227, VTD232, and VTD263, were able to inhibit HIV-1 replication in MDM. Furthermore, we showed that VTD227, but not VTD232 and VTD263, can directly bind to Vpr. Our results indicate that three new compounds and their derivatives represent new drugs targeting HIV-1 replication and can be potentially used in clinics to improve the current antiretroviral therapy.

Investigation of HIV-1 Viral Protein R Inhibitory Activities of Twelve Thai Medicinal Plants and Their Commercially Available Major Constituents

Viral protein R (Vpr) is an accessory protein in Human immunodeficiency virus-1 (HIV-1) and has been suggested as an attractive target for HIV disease treatment. Investigations of the ethanolic extracts of twelve Thai herbs revealed that the extracts of the Punica granatum fruits, the Centella asiatica aerials, the Citrus hystrix fruit peels, the Caesalpinia sappan heartwoods, the Piper betel leaves, the Alpinia galangal rhizomes, the Senna tora seeds, the Zingiber cassumunar rhizomes, the Rhinacanthus nasutus leaves, and the Plumbago indica roots exhibited the anti-Vpr activity in HeLa cells harboring the TREx plasmid encoding full-length Vpr (TREx-HeLa-Vpr cells). Moreover, the investigation of the selected main constituents in Punica granatum, Centella asiatica, A. galangal, and Caesalpinia sappan indicated that punicalagin, asiaticoside, ellagic acid, madecassic acid, madecassoside, zingerone, brazilin, and asiatic acid possessed anti-Vpr activities at the 10 μM concentration. Among the tested extracts and compounds, the extracts from Centella asiatica and Citrus hystrix and the compounds, punicalagin and asiaticoside, showed the most potent anti-Vpr activities without any cytotoxicity, respectively.

Shanpanootols G and H, Diterpenoids from the Rhizomes of Kaempferia pulchra Collected in Myanmar and Their Vpr Inhibitory Activities

Two new trihydroxy derivative of Δ^8(14),15-isopimarane diterpenoids, shanpanootols G (1) and H (2), along with three known analogues were isolated from the ethyl acetate-soluble extract of Kaempferia pulchra rhizomes collected in Shan State of Myanmar. The structures of these compounds including their absolute configurations were elucidated by the combination of one dimensional (1D) and 2D-NMR spectroscopic methods, high resolution mass spectrometric technique, and the experimental and the calculated electronic circular dichroism (ECD) data. The isopimarane diterpenoids (1-5) were tested for their Viral protein R (Vpr) inhibitory activities against TREx-HeLa-Vpr cells. Shanpanootol H (2) and (1R,2S,5S,9R,10S,13R)-1,2-dihydroxypimara-8(14),15-dien-7-one (4) exhibited anti-Vpr activities at the 5 µM treated dose.

Potential drug development and therapeutic approaches for clinical intervention in COVID-19

While the vaccination is now available to many countries and will slowly dissipate to others, effective therapeutics for COVID-19 is still illusive. The SARS-CoV-2 pandemic has posed an unprecedented challenge to researchers, scientists, and clinicians and affected the wellbeing of millions of people worldwide. Since the beginning of the pandemic, a multitude of existing anti-viral, antibiotic, antimalarial, and anticancer drugs have been tested, and some have shown potency in the treatment and management of COVID-19, albeit others failed to leave any positive impact and a few also became controversial as they showed mixed clinical outcomes. In the present article, we have brought together some of the candidate therapeutic drugs being repurposed or used in the clinical trials and discussed their clinical efficacy and safety for COVID-19.

A New Monoterpene from the Rhizomes of Alpinia galanga and Its Anti-Vpr Activity

A new menthane-type monoterpene, alpigalanol (1), together with four known terpenes (2-5) were isolated from the ethyl acetate soluble fraction of the 70 % ethanol extract of the Alpinia galanga rhizomes. The structure of 1 was determined by spectroscopic analyses, including 1D- and 2D-NMR. The extract of the A. galanga rhizomes and all isolated compounds (1-5) possessed Vpr inhibitory activities against the TREx-HeLa-Vpr cells at a concentration of 1.25 μM without showing any cytotoxicity.

Pyrrolactams from Marine Sponge Stylissa massa Collected from Myanmar and Their Anti-Vpr Activities

A new brominated pyrrolactam stylissaol A (1) together with four known analogues, 2-bromoaldisine, aldisine, spongiacidin D, and Z-hymenialdisine, were isolated from the EtOAc extract of marine sponge Stylissa massa collected in Myanmar. The absolute configuration at C-10 of 1 was determined as R by the electronic circular dichroism (ECD) data. Among the isolated compounds, 2-bromoaldisine showed anti-Viral Protein R (Vpr) activity against TREx-HeLa-Vpr cells with an effective dose of 10 µM and its potency was comparable to that of positive control damnacanthal.

Anti-Vpr activities of sesqui- and diterpenoids from the roots and rhizomes of Kaempferia candida

New copaene-type and nerolidol-type sesquiterpenoids, 7-hydroxymustakone (1) and 15-hydroxynerolidol (2), and a 15-norlabdane diterpenoid, kaempcandiol (3), together with four known compounds (4-7) were isolated from the chloroform extract of Kaempferia candida roots and rhizomes. The structures of the new compounds 1-3 were elucidated based on 1D and 2D NMR and HRESIMS spectroscopic analyses. The extract of the K. candida roots and rhizomes and all isolated compounds 1-7 possessed HIV-1 viral protein R (Vpr) inhibitory activities on the TREx-HeLa-Vpr cell line at a 5 μM concentration, without detectable cytotoxicity.

Indian Medicinal Plants and Formulations and Their Potential Against COVID-19-Preclinical and Clinical Research

The cases of COVID-19 are still increasing day-by-day worldwide, even after a year of its first occurrence in Wuhan city of China. The spreading of SARS-CoV-2 infection is very fast and different from other SARS-CoV infections possibly due to structural differences in S proteins. The patients with severe diseases may die due to acute respiratory distress syndrome (ARDS) caused by systemic inflammatory reactions due to the excessive release of pro-inflammatory cytokines and chemokines by the immune effector cells. In India too, it is spreading very rapidly, although the case fatality rate is below 1.50% (https://www.statista.com), which is markedly less than in other countries, despite the dense population and minimal health infrastructure in rural areas. This may be due to the routine use of many immunomodulator medicinal plants and traditional AYUSH formulations by the Indian people. This communication reviews the AYUSH recommended formulations and their ingredients, routinely used medicinal plants and formulations by Indian population as well as other promising Indian medicinal plants, which can be tested against COVID-19. Special emphasis is placed on Indian medicinal plants reported for antiviral, immunomodulatory and anti-allergic/anti-inflammatory activities and they are categorized for prioritization in research on the basis of earlier reports. The traditional AYUSH medicines currently under clinical trials against COVID-19 are also discussed as well as furtherance of pre-clinical and clinical testing of the potential traditional medicines against COVID-19 and SARS-CoV-2. The results of the clinical studies on AYUSH drugs will guide the policymakers from the AYUSH systems of medicines to maneuver their policies for public health, provide information to the global scientific community and could form a platform for collaborative studies at national and global levels. It is thereby suggested that promising AYUSH formulations and Indian medicinal plants must be investigated on a priority basis to solve the current crisis.

In silico evaluation of the compounds of the ayurvedic drug, AYUSH-64, for the action against the SARS-CoV-2 main protease

Background

Outbreak of Corona Virus Disease in late 2019 (COVID-19) has become a pandemic global Public health emergency. Since there is no approved anti-viral drug or vaccine declared for the disease and investigating existing drugs against the COVID-19.

Objective

AYUSH-64 is an Ayurvedic formulation, developed and patented by Central Council of Research in Ayurvedic Sciences, India, has been in clinical use as anti-malarial, anti-inflammatory, anti-pyretic drug for few decades. Thus, the present study was undertaken to evaluate AYUSH-64 compounds available in this drug against Severe Acute Respiratory Syndrome-Corona Virus (SARS-CoV-2) Main Protease (M^pro; PDB ID: 6LU7) via in silico techniques.

Materials and methods

Different molecular docking software's of Discovery studio and Auto Dock Vina were used for drugs from selected AYUSH-64 compounds against SARS-CoV-2. We also conducted 100 ns period of molecular dynamics simulations with Desmond and further MM/GBSA for the best complex of AYUSH-64 with M^pro of SARS-CoV-2.

Results

Among 36 compounds of four ingredients of AYUSH-64 screened, 35 observed to exhibits good binding energies than the published positive co–crystal compound of N3 pepetide. The best affinity and interactions of Akuammicine N-Oxide (from Alstonia scholaris) towards the M^pro with binding energy (AutoDock Vina) of −8.4 kcal/mol and Discovery studio of Libdock score of 147.92 kcal/mol. Further, molecular dynamics simulations with MM-GBSA were also performed for M^pro– Akuammicine N-Oxide docked complex to identify the stability, specific interaction between the enzyme and the ligand. Akuammicine N-Oxide is strongly formed h-bonds with crucial M^pro residues, Cys145, and His164.

Conclusion

The results provide lead that, the presence of M^pro– Akuammicine N-Oxide with highest M^pro binding energy along with other 34 chemical compounds having similar activity as part of AYUSH-64 make it a suitable candidate for repurposing to management of COVID-19 by further validating through experimental, clinical studies.

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Main protease (M^pro) is a molecular drug target for the 2019-nCoV of epidemic disease of COVID-19.

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Docking strategies implemented to identify AUSH-64 having dual role as immunomodualtor and inhibition against M^pro of SARS-CoV-2.

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Molecular dynamics stability analysis revealed that 2019-nCoV M^pro – Akuammicine N-Oxide is stable.

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Akuammicine N-Oxide may represent potential treatment options against M^pro of 2019-nCoV.

Bioactive Compounds from Medicinal Plants in Myanmar

Myanmar is a country with rich natural resources and of these, medicinal plants play a vital role in the primary health care of its population. The people of Myanmar have used their own system of traditional medicine inclusive of the use of medicinal plants for 2000 years. However, systematic and scientific studies have only recently begun to be reported. Researchers from Japan, Germany, and Korea have collaborated with researchers in Myanmar on medicinal plants since 2000. During the past two decades, over 50 publications have been published in peer-reviewed journals. Altogether, 433 phytoconstituents, including 147 new and 286 known compounds from 26 plant species consisting of 29 samples native to Myanmar, have been collated. In this contribution, phytochemical and biological investigations of these plants, including information on traditional knowledge are compiled and discussed.

Bellidifolin Inhibits Proliferation of A549 Cells by Regulating STAT3/COX-2 Expression and Protein Activity

Objectives

Bellidifolin (BEL) is one type of tetraoxygenated xanthone that is particularly found in Swertia and Gentiana (Gentianaceae). Despite its broad range of pharmacological activities, it is still unclear whether BEL could be used for lung cancer treatment. Hence, we presently demonstrate the roles of BEL towards the proliferative inhibition of the prototypical A549 lung cancer cells.

Materials and Methods

The antiproliferative activity of BEL was initially verified by cellular experiments. A network pharmacology method was then pursued to assess BEL potential molecular targets from the platform for pharmacological analysis of Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP). Disease enrichment of potential targets and construction of compound-target-disease network maps were performed based on a total of 20 diseases. Two core targets related to the BEL-mediated effect in A549 cells were obtained by importing potential targets into a protein-protein interaction database (STRING) and also analyzing respective data of related targets into this database. Last, these core targets were examined by in vitro analysis and molecular docking.

Results

CCK8 assays indicated that treatment with 50-100 μm BEL had an inhibitory effect on the proliferation of human A549 lung cancer cells, whereas this effect was time- and concentration-dependent. As control, treatment with 50-100 μm BEL did not inhibit the proliferation of normal lung epithelial cells (BEAS-2b cell line). H&E staining of BEL-treated A549 cells showed that, upon an increase of drug concentration, nuclear condensation and fragmentation were largely observed. Cell cycle analysis showed that in vitro treatment with 75-100 μm BEL could block A549 cells in S and G2 phases. Western blot analyses showed that after 72 hours of BEL treatment, the level of caspase-8/3 in A549 cells increased, and the level of PARP1 decreased in a dose-dependent manner. Network pharmacology analysis also indicated that lung cancer was the major disease susceptible to BEL treatment. At the same time, STAT3 and COX-2 were identified as two core targets of BEL in lung cancer treatment. Functional analyses further revealed that the cytotoxicity effect of BEL in A549 cells potentially involved the STAT3/COX-2 pathway. Moreover, molecular docking analysis indicated that BEL structure properly matches with COX-2 and STAT3 in space shape, thus illustrating the putative molecular mechanism of BEL's anticancer effect.

Conclusions

Based on a series of in vitro analyses, network pharmacology, and molecular docking, the potential mechanism involving the antiproliferative and cytotoxic effects of BEL in lung cancer cells was investigated. Our study may help providing some theoretical basis for the discovery of novel phytotherapy drugs applicable for the treatment of lung cancer.

Anti-Vpr activities of homodrimane sesquiterpenoids and labdane diterpenoids from Globba sherwoodiana rhizomes

Two new homodrimane sesquiterpenoids, globbatones A and B (1 and 2), and one 16-norlabdane diterpenoid, globbatone C (3), together with two new naturally occurring, (E)-labda-8(17),12-diene-15,16-olide (4) and γ-bicyclohomofarnesen-12-ol (5), and one known homodrimane sesquiterpenoid (6), nine known labdane diterpenoids (7-15), and one isospongian diterpenoid (16), were isolated from the chloroform extract of Globba sherwoodiana rhizomes. The structures of the new compounds 1-3 were elucidated based on 1D and 2D NMR and HRESIMS spectroscopic analyses. The chloroform extract of G. sherwoodiana rhizomes and 10 μM concentrations of some of its constituents 1, 3, 4, 8, 9, 12, and 14 showed the moderate anti-Vpr activities, without cytotoxic effects on the TREx-HeLa-Vpr cell line.

Impact of HIV-1 Vpr manipulation of the DNA repair enzyme UNG2 on B lymphocyte class switch recombination

Background

HIV-1 Vpr encodes a 14 kDa protein that has been implicated in viral pathogenesis through modulation of several host cell functions. In addition to pro-apoptotic and cytostatic properties, Vpr can redirect cellular E3 ubiquitin ligases (such as DCAF1-Cul4A E3 ligase complex) to target many host proteins and interfere with their functions. Among them, Vpr binds the uracil DNA glycosylase UNG2, which controls genome uracilation, and induces its specific degradation leading to loss of uracil removal activity in infected cells. Considering the essential role of UNG2 in antibody diversification in B-cells, we evaluated the impact of Vpr on UNG2 fate in B lymphocytes and examined the functional consequences of UNG2 modulations on class switch recombination (CSR).

Methods

The impact of Vpr-induced UNG2 deregulation on CSR proficiency was evaluated by using virus-like particles able to deliver Vpr protein to target cells including the murine model CSR B cell line CH12F3 and mouse primary B-cells. Co-culture experiments were used to re-examine the ability of Vpr to be released by HIV-1 infected cells and to effectively accumulate in bystander B-cells. Vpr-mediated UNG2 modulations were monitored by following UNG2 protein abundance and uracil removal enzymatic activity.

Results

In this study we report the ability of Vpr to reduce immunoglobulin class switch recombination (CSR) in immortalized and primary mouse B-cells through the degradation of UNG2. We also emphasize that Vpr is released by producing cells and penetrates bystander B lymphocytes.

Conclusions

This work therefore opens up new perspectives to study alterations of the B-cell response by using Vpr as a specific CSR blocking tool. Moreover, our results raise the question of whether extracellular HIV-1 Vpr detected in some patients may manipulate the antibody diversification process that engineers an adapted response against pathogenic intruders and thereby contribute to the intrinsic B-cell humoral defect reported in infected patients.

AYUSH 64, a polyherbal Ayurvedic formulation in Influenza-like illness - Results of a pilot study

BACKGROUND

Influenza-like Illness (ILI) refers to a wide range of viral infections with an important cause of morbidity and mortality worldwide. The global incidence of ILI is estimated at 5-10% in adults and 20-30% in children. In India influenza accounts for 20-42% of monthly acute medical illness hospitalizations during the peak rainy season. AYUSH-64, a poly-herbal drug, is in practice for 40 years for various clinical conditions like fevers, microfilaremia, and inflammatory conditions.

OBJECTIVE

A pilot study was conducted to evaluate the safety and efficacy of Ayurvedic formulation, AYUSH-64 in clinically diagnosed ILI for accelerating the recovery.

MATERIAL AND METHODS

A prospective, open-label, nonrandomized, single group, single-center pilot clinical study with pre-test and post-test design was conducted at Raja Ramdeo Anandilal Podar Central Ayurveda Research Institute for Cancer, Mumbai, an institute of Central Council for Research in Ayurvedic Sciences (CCRAS) between June 2018 and July 2019. A total of 38 participants of clinically diagnosed ILI (18-65 years) were studied with an one-week intervention of 'AYUSH 64' in a dose of 3 gm/day and three weeks post-treatment observation period. Assessment of parameters viz. improvement in the symptoms of ILI, frequency of usage of acetaminophen, antihistaminic and cough syrup, hematology, liver function and kidney function tests along with incidence of secondary complications, and time to return to a normal routine was done.

RESULTS

One-week intervention of AYUSH 64 helped to recover from ILI symptoms with reduced frequency of usage of acetaminophen and antihistaminic. The intervention was safe on hematology and biochemical parameters. No serious adverse effects were observed during the study.

CONCLUSION

AYUSH 64 along-with standard care in ILI is safe and efficacious and this may be used in other viral infections with pyrexia as add-on to standard care for early recovery and better outcome.