Controlling pathogenesis in Candida albicans by targeting Efg1 and Glyoxylate pathway through naturally occurring polyphenols.

Candida albicans has frequently shown resistance to azoles, the commonly used antifungal drugs. Efg1 has dual role under normoxia and hypoxia supporting infection. It is the major regulator of morphogenesis in C. albicans requisite for its pathogenesis. Targeting this protein is expected to render Candida ineffective to undergo filamentation causing virulence. Further the glyoxylate pathway supports the stress resistance and pathogenesis. In the present study an in silico approach and in vitro validation has been performed to find the potential role of polyphenols in controlling hyphal growth in C. albicans. The aspect of changes biome which may provide required niche to the pathogen has been checked which certainly opens the doors towards safe natural polyphenol-based drugs as potent antifungals.

Synthesis and applications of biogenic nanomaterials in drinking and wastewater treatment.

The continuous increase in water pollution by various organic & inorganic contaminants has become a major issue of concern worldwide. Furthermore, the anthropogenic activities for the manufacturing of various products have boosted this problem manifold. To overcome this serious issue, nanotechnology has initiated to explore various proficient strategies to treat waste water in a more precise and accurate way with the support of various nanomaterials. In recent times, nanosized materials have proved their applicability to provide clean and affordable water treatment technologies. The exclusive features such as high surface area and mechanical properties, greater chemical reactivity, lower cost and energy, efficient regeneration for reuse allow the nanomaterials perfect for water remediation. But the conventional routes of synthesis of nanomaterials encompass the involvement of hazardous and volatile chemicals; therefore the use of nanomaterials further creates the secondary pollution. This issue has intrigued the scientists to develop biogenic pathways and procedures which are environmentally safer and inexpensive. It has led to the new trends that involve developing bio-inspired nano-scale adsorbents and catalysts for the removal and degradation of a wide range of water pollutants. Carbohydrates, proteins, polymers, flavonoids, alkaloids and several antioxidants obtained from plants, bacteria, fungi, and algae have proven their effectiveness as capping and stabilizing agents during manufacture of nanomaterials. Application of biogenic nanomaterials for waste water treatment is relatively newer but rapidly escalating area of research. In the present review, promises and challenges for the synthesis of various biogenic nanomaterials and their potential applications in waste water treatment and/or water purification have been discussed.

In-silico designing, chemical synthesis, characterization and in-vitro assessment of antibacterial properties of some analogues of curcumin.

In the present work two key regulator proteins, monomeric MipZ of Caulobacter vibrioides (similar to Pseudomonas aeruginosa) and Pyruvate kinase of Staphylococcus aureus were docked with curcumin, the wonder molecule from the spice turmeric and structures of its twelve analogues were designed, synthesized and tested in-vitro for antibacterial activity. Based on the test results a comparative account of the probable mechanism has been given Two major alternative targets are possible for antibacterial activity of drug molecules. These may be bacterial cell wall lipids or the proteins responsible for smooth functioning of bacterial cells. In the former case, due to significant difference in the structural components of the cell walls of Gram positive and Gram negative bacteria, it is improbable that same ligand will affect both equally. Majority of commercial drugs are anti-Gram negative bacteria while in the present work we have found most effective drugs against Gram positive bacteria. Based on the test results a comparative account of the probable mechanism has been given. Evidently along with the cell wall damaging mechanism other parallel mechanisms are also operative.

Restraining Pathogenicity in Candida albicans by Taxifolin as an Inhibitor of Ras1-pka Pathway.

Candida albicans is one of the most virulent and opportunistic fungal strains. In the present scenario, majority metabolic imbalances and unsuccessful treatments of some severe diseases including cancer, diabetes, HIV, psoriasis are because of invasive Candida emergence. Being a beneficial integral part of human biome, its elimination is not possible. The major pathogenicity characteristics in Candida involve hyphal growth, biofilm formation, HSP90 down regulation and genetic modifications. Ras1-pka pathway initiated by HSP90 down regulation is important for hyphal growth and has been focused in the present study. The principle transcriptional factors that induce hyphal growth causing invasiveness and virulence through this pathway have been identified as Tec1 and Rfg1. In the present study, taxifolin, a naturally occurring polyphenol, has been identified as inhibitor for both the transcriptional factors in parallel.

Computation-based virtual screening for designing novel antimalarial drugs by targeting falcipain-III: a structure-based drug designing approach.

BACKGROUND & OBJECTIVES: Cysteine proteases (falcipains), a papain-family of enzymes of Plasmodium falciparum, are responsible for haemoglobin degradation and thus necessary for its survival during asexual life cycle phase inside the human red blood cells while remaining non-functional for the human body. Therefore, these can act as potential targets for designing antimalarial drugs. The P. falciparum cysteine proteases, falcipain-II and falcipain- III are the enzymes which initiate the haemoglobin degradation, therefore, have been selected as targets. In the present study, we have designed new leupeptin analogues and subjected to virtual screening using Glide at the active site cavity of falcipain-II and falcipain-III to select the best docked analogues on the basis of Glide score and also compare with the result of AutoDock. The proposed analogues can be synthesized and tested in vivo as future potent antimalarial drugs. METHODS: Protein falcipain-II and falcipain-III together with bounds inhibitors epoxysuccinate E64 (E64) and leupeptin respectively were retrieved from protein data bank (PDB) and latter leupeptin was used as lead molecule to design new analogues by using Ligbuilder software and refined the molecules on the basis of Lipinski rule of five and fitness score parameters. All the designed leupeptin analogues were screened via docking simulation at the active site cavity of falcipain-II and falcipain-III by using Glide software and AutoDock. RESULTS: The 104 new leupeptin-based antimalarial ligands were designed using structure-based drug designing approach with the help of Ligbuilder and subjected for virtual screening via docking simulation method against falcipain-II and falcipain-III receptor proteins. The Glide docking results suggest that the ligands namely result_037 shows good binding and other two, result_044 and result_042 show nearly similar binding than naturally occurring PDB bound ligand E64 against falcipain-II and in case of falcipain-III, 15 designed leupeptin analogues having better binding affinity compared to the PDB bound inhibitor of falcipain-III. The docking simulation results of falcipain-III with designed leupeptin analogues using Glide compared with AutoDock and find 80% similarity as better binder than leupeptin. INTERPRETATION & CONCLUSION: These results further highlight new leupeptin analogues as promising future inhibitors for chemotherapeutic prevention of malaria. The result of Glide for falcipain-III has been compared with the result of AutoDock and finds very less differences in their order of binding affinity. Although there are no extra hydrogen bonds, however, equal number of hydrogen bonds with variable strength as compared to leupeptin along with the enhanced hydrophobic and electrostatic interactions in case of analogues supports our study that it holds the ligand molecules strongly within the receptor. The comparative e-pharmacophoric study also suggests and supports our predictions regarding the minimum features required in ligand molecule to behave as falcipain- III inhibitors and is also helpful in screening the large database as future antimalarial inhibitors.

Artificial Intelligence in Accelerating Drug Discovery and Development.

Drug discovery and development are critical processes that enable the treatment of wide variety of health-related problems. These are time-consuming, tedious, complicated, and costly processes. Numerous difficulties arise throughout the entire process of drug discovery, from design to testing. Corona Virus Disease 2019 (COVID-19) has recently posed a significant threat to global public health. SARS-Cov-2 and its variants are rapidly spreading in humans due to their high transmission rate. To effectively treat COVID-19, potential drugs and vaccines must be developed quickly. The advancement of artificial intelligence has shifted the focus of drug development away from traditional methods and toward bioinformatics tools. Computer-aided drug design techniques have demonstrated tremendous utility in dealing with massive amounts of biological data and developing efficient algorithms. Artificial intelligence enables more effective approaches to complex problems associated with drug discovery and development through the use of machine learning. Artificial intelligence-based technologies improve the pharmaceutical industry's ability to discover effective drugs. This review summarizes significant challenges encountered during the drug discovery and development processes, as well as the applications of artificial intelligence-based methods to overcome those obstacles in order to provide effective solutions to health problems. This may provide additional insight into the mechanism of action, resulting in the development of vaccines and potent substitutes for repurposed drugs that can be used to treat not only COVID-19 but also other ailments.

Anti-inflammatory effect of curcumin in an accelerated senescence model of Wistar rat: an in vivo and in-silico study.

Curcumin, a biphenolic substance derived from turmeric (Curcuma longa), offers a number of health-beneficial effects, including anti-inflammatory, cardiovascular protection, anti-cancerous, and anti-angiogenic. By interacting with the PPARγ (Peroxisome Proliferator-Activated Receptor-γ), curcumin inhibits NF-κB. These biological outcomes seem to be the outcome of NF-κB inhibition mediated by curcumin. The current study explores the in vivo impact of curcumin on several inflammatory parameters during aging in Wistar rats. An in-silico docking simulation study using Maestro and Desmond, Schrödinger, was carried out to further validate the experimental findings. According to our observation, rats given curcumin supplementation had a considerably (p ≤ 0.05) reduced level of inflammation. By generating numerous polar and hydrophobic interactions and exhibiting little conformational deviation throughout the simulation, in silico investigations showed that the proposed ligand curcumin had a high affinity for the enzyme COX-2. During simulation, protein-ligand complexes of curcumin with the other targets viz. 5-LOX, TNF-α and IL-6 also demonstrated improved binding and minimal fluctuation. The COX-2 and 5-LOX enzymes and the cytokines (TNF-α and IL-6) implicated in inflammation may have been inhibited by curcumin, highlighting its function as a multi-target inhibitor. Our study provides convincing support for the idea that eating a diet high in curcumin may help to reduce inflammation and help to explain some of its health-beneficial effects.Communicated by Ramaswamy H. Sarma.

Modulation of GPCR receptors common to gut inflammatory diseases and neuronal disorders, Alzheimer's and Parkinson's diseases as druggable targets through Withania somnifera bioactives: an in silico study.

Microorganisms in human gastrointestinal tract have profound influence on the transformation of food into metabolites which can impact human health. Along with playing crucial roles in regulating and modulating various metabolic reactions and life processes, dysbiosis of gut microbiota also affects the permeability of gut and blood-brain barrier. This increases the chance of age-related neurological disorders' like Alzheimer's and Parkinson's diseases. Withania somnifera (W. somnifera) has been proclaimed as a virtuous plant for the treatment of neurodegenerative diseases and many other problems. We have studied the bioactive components of W. somnifera for combined treatment of gut-dysbiosis led bowel diseases (Inflammatory Bowel Disease, Irritable Bowel Syndrome) and the most common neurodegenerative diseases through common potential targets. This approach can solve along with curing the neurodegenerative diseases, the factors causing these diseases would also be obstructed from entering the brain, consonantly curing Inflammatory Bowel Disease and Irritable Bowel Syndrome. Our work on GPCR receptors common to gut inflammatory diseases and neuronal disorders through Network Pharmacology, Molecular docking and Dynamic Simulation approach has shown that modulation of these receptors with bioactive compounds present in W. somnifera can result in effective control of these diseases. We have found five proteins (HTR1A, HTR1B, HTR2A, HTR2B & HTR7) and five best lead compounds (Withanolide A, B, E, Q & Anahygrine) against these targets after molecular docking analysis. Our simulation studies have finally shown that amongst these five HTR1A and HTR7 proteins are the best targets with the leads Withanolide E and Withanolide A against them, respectively.Communicated by Ramaswamy H. Sarma.

Identification of candidate target genes of oral squamous cell carcinoma using high-throughput RNA-Seq data and in silico studies of their interaction with naturally occurring bioactive compounds.

Oral Squamous Cell Carcinoma (OSCC) accounts for more than 90% of all kinds of oral neoplasms that develop in the oral cavity. It is a type of malignancy that shows high morbidity and recurrence rate, but data on the disease's target genes and biomarkers is still insufficient. In this study, in silico studies have been performed to find out the novel target genes and their potential therapeutic inhibitors for the effective and efficient treatment of OSCC. The DESeq2 package of RStudio was used in the current investigation to screen and identify differentially expressed genes for OSCC. As a result of gene expression analysis, the top 10 novel genes were identified using the Cytohubba plugin of Cytoscape, and among them, the ubiquitin-conjugating enzyme (UBE2D1) was found to be upregulated and playing a significant role in the progression of human oral cancers. Following this, naturally occurring compounds were virtually evaluated and simulated against the discovered novel target as prospective drugs utilizing the Maestro, Schrodinger, and Gromacs software. In a simulated screening of naturally occurring potential inhibitors against the novel target UBE2D1, Epigallocatechin 3-gallate, Quercetin, Luteoline, Curcumin, and Baicalein were identified as potent inhibitors. Novel identified gene UBE2D1 has a significant role in the proliferation of human cancers through suppression of 'guardian of genome' p53 via ubiquitination dependent pathway. Therefore, the treatment of OSCC may benefit significantly from targeting this gene and its discovered naturally occurring inhibitors.Communicated by Ramaswamy H. Sarma.

Glutamoyl diester of the dietary polyphenol curcumin offers improved protection against peroxynitrite-mediated nitrosative stress and damage of brain mitochondria in vitro: implications for Parkinson's disease.

Oxidative/nitrosative stress plays a crucial role in Parkinson's disease (PD) by triggering mitochondrial dysfunction. Nitrosative stress is mediated by reactive species such as peroxynitrite (PN) which could damage biomolecules thereby impinging on the cellular machinery. We observed that PN (0-1000 µM) inhibited brain mitochondrial complex I (CI) activity in a dose-dependent manner with concomitant tyrosine nitration of proteins. We also observed that exposure to PN at low concentrations (62.5-125 µM) significantly decreased the mitochondrial membrane potential and affected the mitochondrial integrity at higher doses (500-750 µM) as indicated by the mitochondrial swelling experiment. Therefore, it could be surmised that compounds that prevent such mitochondrial damage might have therapeutic value in neurological conditions such as PD. We previously showed that curcumin could detoxify PN and protect against CI inhibition and protein nitration. However, the therapeutic potential of curcumin is constrained by limited bioavailability. To address this issue and obtain improved antioxidants, three bioconjugates of curcumin (Di-demethylenated piperoyl, di-valinoyl and di-glutamoyl esters) were generated and tested against PN-mediated nitrosative stress and mitochondrial damage. We found that among the bioconjugates, the glutamoyl diester of curcumin showed improved protection against PN-dependent CI inhibition and protein nitration compared to other conjugates. Di-glutamoyl curcumin protected dopaminergic neurons against 1-methyl-4-phenylpyridinium (MPP(+))-mediated neuronal death. These effects were improved compared to curcumin alone suggesting that di-glutamoyl curcumin could be a better neuroprotective agent in neurodegenerative diseases such as PD.

Two pronged approach for prevention and therapy of COVID-19 (Sars-CoV-2) by a multi-targeted herbal drug, a component of ayurvedic decoction.

INTRODUCTION: SARS-CoV-2 a new virus of the zoonotic coronavirus family causes the disease COVID-19, which has become a global pandemic. One of the ways for prevention of COVID-19 is by disabling its spike protein which results in inhibiting its binding with angiotensin-converting enzyme 2 (ACE-2). The other alternative is to inhibit its replication once inside the body. The aim of this study was to explore the literature to identify whether there were any Ayurvedic remedies which contained ingredients which demonstrated this dual effect. METHODS: In silico studies were carried out to find the structures of the targets i.e. spike protein of the virus and its main protease (Mpro). Databases were searched to identify the composition of Ayurvedic decoctions used for respiratory ailments. RESULTS: We have found that two components out of 26 active ingredients of Ayurvedic decoctions are strong binders for spike protein as well as corresponding Mpro (3CL protease) which plays an essential role in mediating viral replication and transcription, making it an attractive antiviral drug target. Out of 26 components of Ayurvedic herbal decoction used for influenza, one compound was found to be most active. It is a well-known antioxidant, antinflammatory and hepatoprotective molecule. CONCLUSION: The resultant compound could act as a repurposed drug or like other methoxyphenols, could be a good lead molecule for a potent drug for COVID-19.

Design, synthesis and characterization of some bioactive conjugates of curcumin with glycine, glutamic acid, valine and demethylenated piperic acid and study of their antimicrobial and antiproliferative properties.

The monoesters of curcumin, a symmetric diphenol with valine and glycine have been prepared by a novel solid phase synthesis and its diesters with valine, glutamic acid and demethylenated piperic acid have been prepared by solution phase method. The assessment of their antimicrobial and anticancer (antiproliferative) activities suggested that diesters of curcumin are relatively more active than curcumin itself due to their increased solubility, slow metabolism and better cellular uptake. Furthermore, significant observation was that monoesters of curcumin have even better antimicrobial activity than their corresponding diesters, emphasizing the role of free phenolic group. The conjugate of curcumin with demethylenated piperic acid in which methylenedioxy ring was open also shows enhanced activity than the corresponding piperic acid conjugate, emphasizing the role of free phenolics in the transport or in the binding processes.

Structure-Based Drug Designing and Simulation Studies for Finding Novel Inhibitors of Heat Shock Protein (HSP70) as Suppressors for Psoriasis.

Psoriasis is a chronic immune-mediated inflammatory skin disorder. Heat shock proteins (HSPs) have been witnessed as a potential drug target for inhibition of psoriatic cell differentiation. The expression level of HSP is increased when the cells get exposed to elevated temperature, oxidative stress and nutritional deficiencies and thus plays major role in psoriatic progression pathway. Immunoreactivity intensity distribution index scores for HSP70 expression is significantly higher in psoriatic patients compared to normal. In the present work, the 3D structure of human Hsp70 has been taken. Inhibition of HSP70 can control the severity of psoriasis up to many folds; thus, virtual screening was performed against lead-like, drug-like and some natural product of ZINC database. The screened ligands were further introduced to ADMET prediction and simulations to see the drug proficiency and likeness property. The molecular dynamic of system was found stable during simulation trajectory and not much of significant changes occurred in the conformation of the protein-ligand complex. Thus, present study in all probability might prove useful for future design of new derivatives with higher potency and specificity.

Telomerase targeted anticancer bioactive prodrug by antisense-based approach.

A deoxy 11-mer oligonucleotide 5'-GTTAGGGTTAG-3', complementary to a repeat sequence of human telomerase RNA template has been linked through phosphate and a C-2 linker to a bioactive tetraglycine conjugate of curcumin, a well-known antitumor herbal spice component of turmeric. This molecule has been transfected into KB and HeLa cell lines and found to affect cell growth in the former. This DNA-curcumin-tetraglycine acts as a prodrug being targeted by antisense mechanism to telomerase.

Recent Wetting and Glacier Expansion in the Northwest Himalaya and Karakoram.

Hydroclimatic variability driven by global warming in the climatically vulnerable cold semi-arid to arid northwest (NW) Himalaya is poorly constrained due to paucity of continuous weather records and annually resolved proxies. Applying a network of annually resolved tree-ring-width chronologies from semi-arid region of Kishtwar, Jammu and Kashmir, India, we reconstructed April-May standardized precipitation index extending back to A.D. 1439 (576 years). The reconstructed series is featured by the most conspicuous long-term droughts during the 15th to early 17th centuries followed by a general wetting, with 1984-2014 being the wettest interval in the past 576 years. The data, consistent with other independently developed tree-ring-based hydrological records from cold semi-arid to arid NW Himalaya and Karakoram, point to an increased regional wetting in the recent decades. Such an increased wetting might have led to the anomalous behaviour of glaciers in the NW Himalaya and Karakoram in contrast to the general receding trends in the central and eastern Himalaya.

Inhibition of P-Glycoprotein Mediated Efflux of Paclitaxel by Coumarin Derivatives in Cancer Stem Cells: An In Silico Approach.

P-glycoprotein (P-gp) is well known to cause multidrug resistance (MDR) in cancer cells. This MDR leads to cancer recurrence which is a major obstacle in cancer treatment. High P-gp expression has been observed in the population of cancer stem cells (CSCs) having self-renewal potential. Early detection and inhibition of these CSCs is directly beneficial to cancer treatment. In this study coumarin derivatives are used to inhibit efflux process and thereby enhance bioavailability of various drugs like paclitaxel (PTX). This drug is most commonly used for the treatment of cancers of breast, ovary, head and neck. Coumarin derivatives can be used to reduce the growth of breast cancer stem cells through P-gp mediated efflux inhibition and paclitaxel bioavailability enhancement. With the use of computational approaches including molecular docking simulation and pharmacophore study, few coumarin derivatives have been found to be more potential inhibitors of P-gp mediated efflux. Based on high affinity inhibitors, new coumarin derivatives have been designed and docked at active site cavity of P-gps. Some newly designed coumarin derivatives were found to be more potent due to their higher binding affinity towards target protein. The finding that newly designed coumarins can be exploited for inhibition of P-gp mediated efflux in order to enhance paclitaxel bioavailability and can inhibit breast cancer stem cell growth is significant for designing potent anticancer drugs.

Modulation of Erythrocyte Plasma Membrane Redox System Activity by Curcumin.

Plasma membrane redox system (PMRS) is an electron transport chain system ubiquitously present throughout all cell types. It transfers electron from intracellular substrates to extracellular acceptors for regulation of redox status. Curcumin, isolated from Curcuma longa, has modulatory effects on cellular physiology due to its membrane interaction ability and antioxidant potential. The present study investigates the effect of curcumin on PMRS activity of erythrocytes isolated from Wistar rats in vitro and in vivo and validated through an in silico docking simulation study using Molegro Virtual Docker (MVD). Effects of curcumin were also evaluated on level of glutathione (GSH) and the oxidant potential of plasma measured in terms of plasma ferric equivalent oxidative potentials (PFEOP). Results show that curcumin significantly (p < 0.01) downregulated the PMRS activity in a dose-dependent manner. Molecular docking results suggest that curcumin interacts with amino acids at the active site cavity of cytochrome b 5 reductase, a key constituent of PMRS. Curcumin also increased the GSH level in erythrocytes and plasma while simultaneously decreasing the oxidant potential (PFEOP) of plasma. Altered PMRS activity and redox status are associated with the pathophysiology of several health complications including aging and diabetes; hence, the above finding may explain part of the role of curcumin in health beneficial effects.

Differential apoptotic and redox regulatory activities of curcumin and its derivatives.

We have synthesized different bioconjugates of curcumin, which were tested for their pro- and antioxidant properties. In the present study five representative derivatives of curcumin, i.e., 4,4'-di-(O-acetyl) curcumin, 4,4'-di-(O-glycinoyl) curcumin, 4,4'-di-(O-glycinoyl-di-N-piperoyl) curcumin, 4,4'-di-(O-piperoyl) curcumin, and 4,4'-(O,O-cystinoyl)-3,3'-dimethoxydiphenyl-1,6-heptadiene-3,5-dione, were used for testing their apoptotic potential on tumor cells. Dipiperoyl and diglycinoyl derivatives showed higher apoptotic activity at lower concentrations, whereas diacetyl curcumin had slightly lower apoptotic activity on tumor cells. On the other hand, diglycinoyl-dipiperoyl and cystinoyl heptadiene derivatives had lost their apoptotic potential significantly. The apoptotic activity of these derivatives correlated very well with the generation of ROS by the tumor cells, whereas GSH levels remained unaltered. Our studies also indicate downregulation of Bcl-2 and participation of caspase-3 in the apoptotic death of tumor cells.