Publications by authors named "Sharad Kumar Suthar"

There is a long-standing need for inhibitors that selectively target the actomyosin complex, the terminal effector of diverse processes that involve movement in the cells or the body. Such compounds, we term as actomyolytics, hold promise for treating numerous conditions with minimum adverse effects. In this study, we developed efficient synthesis pathways and conducted a detailed structure-activity relationship (SAR) analysis of 144 potential actomyolytics (referred to as the MPH-family) targeting the blebbistatin binding site on myosin-2.

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We report the anticancer activity, structure-activity relationships (SAR), molecular mechanism, and docking studies of nine pentacyclic triterpenoids derived from lantadene A. The NCI-60 cytotoxicity screening of synthesized compounds on 60 human tumor cell lines, representing nine different cancers revealed that compound , bearing dual C-3 and C-22 butyryloxy substitutions at the pentacyclic triterpenoid scaffold, displays remarkable potency with mean growth inhibition of 98.7% at 10 μM.

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Posttranslational modifications of α-synuclein, such as truncation or abnormal proteolysis, are implicated in Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). A key focus of this article includes the proteases responsible for inducing truncation, the specific sites susceptible to truncation, and the resultant influence of these truncated species on the seeding and aggregation of endogenous α-synuclein. We also shed light on the unique structural attributes of these truncated species, and how these modifications can lead to distinctive forms of synucleinopathies.

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Mutations in superoxide dismutase 1 (SOD1) result in misfolding and aggregation of the protein, causing neurodegenerative amyotrophic lateral sclerosis (ALS). In recent years, several new SOD1 variants that trigger ALS have been identified, making it increasingly crucial to understand the SOD1 toxicity pathway in ALS. Here we used an integrated bioinformatics approach, including the Ingenuity Pathway Analysis (IPA) tool to analyze signaling pathways, regulators, functions, and network molecules of SOD1 with an emphasis on ALS.

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Despite the knowledge that mutation, multiplication, and anomalous function of -synuclein cause progressive transformation of -synuclein monomers into toxic amyloid fibrils in neurodegenerative diseases, the understanding of canonical signaling, interaction network molecules, biological functions, and role of -synuclein remains ambiguous. The evolution of artificial intelligence and Bioinformatics tools have enabled us to analyze a vast pool of data to draw meaningful conclusions about the events occurring in complex biological systems. We have taken the advantage of such a Bioinformatics tool, ingenuity pathway analysis (IPA) to decipher the signaling pathways, interactome, biological functions, and role of -synuclein.

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Background: Despite recent advances in the treatment of squamous cell skin cancer (SCSC), the disease persists, and treatment resistance develops. Thus, identifying new targets and developing new therapeutic approaches showing low vulnerability to drug resistance is highly needed.

Purpose: This study aimed to reveal a novel targeted phytotherapeutic strategy for SCSC treatment alone or in combination with standard targeted anticancer molecules.

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Simple and consistent chiral HPLC methods for the efficient separation of enantiomeric blebbistatin derivatives, namely parent compound blebbistatin and derivatives 4-nitroblebbistatin, 4-aminoblebbistatin, 4-dimethylaminoblebbistatin, and 4-t-butylblebbistatin were developed using cellulose tris(3,5-dimethylphenylcarbamate) as a stationary phase (Lux cellulose-1 column). Blebbistatin, 4-aminoblebbistatin, and 4-dimethylaminoblebbistatin racemates were well-separated in normal-phase HPLC conditions while 4-nitroblebbistatin and 4-t-butylblebbistatin were effectively separated in both normal- and reversed-phase HPLC conditions. Furthermore, the order of elution of enantiopure compounds was found to be independent of mobile phase compositions and conditions used, and solely depends on the interaction between the enantiomer and the chiral stationary phase.

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TSPO-associated protein 1 (TSPOAP1) is a cytoplasmic protein and is closely associated with its mitochondrial transmembrane protein partner translocator protein (TSPO). To decipher the canonical signalling pathways of TSPOAP1, its role in human diseases and disorders, and relationship with TSPO; expression analyses of TSPOAP1- and TSPO-associated human genes were performed by Qiagen Ingenuity Pathway Analysis (IPA). In the expression analysis, necroptosis and sirtuin signalling pathways, mitochondrial dysfunction, and inflammasome were the top canonical pathways for both TSPOAP1 and TSPO, confirming the close relationship between these two proteins.

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Blebbistatin, -nitroblebbistatin (NBleb), and -aminoblebbistatin (AmBleb) are highly useful tool compounds as they selectively inhibit the ATPase activity of myosin-2 family proteins. Despite the medical importance of the myosin-2 family as drug targets, chemical optimization has not yet provided a promising lead for drug development because previous structure-activity-relationship studies were limited to a single myosin-2 isoform. Here we evaluated the potential of blebbistatin scaffold for drug development and found that D-ring substitutions can fine-tune isoform specificity, absorption-distribution-metabolism-excretion, and toxicological properties.

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Muscle spasticity after nervous system injuries and painful low back spasm affect more than 10% of global population. Current medications are of limited efficacy and cause neurological and cardiovascular side effects because they target upstream regulators of muscle contraction. Direct myosin inhibition could provide optimal muscle relaxation; however, targeting skeletal myosin is particularly challenging because of its similarity to the cardiac isoform.

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A simple and economical method was developed for the extraction and isolation of pentacyclic triterpenoid lantadene A from the leaves of . The lantadene A displays significant anti-inflammatory and anticancer properties via the inhibition of IKK-mediated NF-κB protein. Therefore, the derivatives of lantadene A were synthesised to further optimise the pharmacophore for anti-inflammatory and anticancer activities.

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The enzyme tyrosinase regulates melanogenesis and skin hyperpigmentation by converting L-3,4-dihydroxyphenylalanine (L-DOPA) into dopaquinone, a key step in the melanin biosynthesis. The present work deals with design and synthesis of various oxindole-based chalcones as monophenolase and diphenolase activity inhibitors of tyrosinase. Among the screened compounds, 4-hydroxy-3-methoxybenzylidene moiety bearing chalcone (7) prepared by one pot reaction of oxindole and vanillin displayed the highest activity against tyrosinase with ICs of 63.

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Nonsteroidal anti-inflammatory drugs (NSAIDs) are one of the widely used medications all over the world, indicated for pain, fever, and inflammation. It is now well established that inflammation and cancer are closely linked with each other. Inflammatory mediators, like cyclooxygenase (COX), vascular endothelial growth factor (VEGF), tumor growth factor (TGF), fibroblast growth factor (FGF), chemokines, and cytokines and related genes, such as inhibitor of nuclear factor-kappa B kinase (IKK) and nuclear factor-kappa B (NF-κB) have been shown to be up-regulated in various cancers.

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The 3-substituted oxindole derivatives were designed, synthesized, and evaluated for antidepressant activity by employing forced swimming test, tail suspension test, and MAO-A inhibition assay. Results of biological studies revealed that the majority of compounds exhibited potent to moderately potent activity and among them, 12 displayed potency comparable to that of the imipramine with %DID of 37.95 and 44.

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NSAIDs are among the most widely prescribed medications across the world, but the gastrointestinal (GI) toxicity still remains the biggest problem and the challenge for current NSAIDs-based therapeutics. The development of selective COX-2 inhibitors was driven by the assumption that selective inhibition of COX-2 would reduce the GI side effects. However, the initial enthusiasm for selective COX-2 inhibitors has faded away due to the emergence of serious side effects associated with the long-term use of these NSAIDs.

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An emulsified gel of (+)-catechin was developed and evaluated topically against 7,12-dimethylbenz(a)anthracene-induced and 12-O-tetradecanoylphorbol-13-acetate-promoted (DMBA-induced and TPA-promoted) squamous cell carcinoma of the skin in BALB/c mice. The biological evaluation outcome indicated that the (+)-catechin emulsified gel increased the activity of oxidative stress biomarkers glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), glutathione reductase (GR), and glutathione peroxidase (GPx), whereas it decreased the level of malondialdehyde (MDA). The mechanistic study showed that genes implicated in the inflammation and cancer, such as cyclooxygenase-2 (COX-2), nuclear factor-kappa B (NF-κB), and inducible nitric-oxide synthase (iNOS), were down-regulated by (+)-catechin emulsified gel while inhibiting an inflammatory mediator prostaglandin E2 (PGE2).

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The new series of pentacyclic triterpenoids reduced lantadene A (3), B (4), and 22β-hydroxy-3-oxo-olean-12-en-28-oic acid (5) analogs were synthesized and tested in vitro for their NF-κB and IKKβ inhibitory potencies and cytotoxicity against A549 lung cancer cells. The lead analog (11) showed sub-micromolar activity against TNF-α induced activation of NF-κB and exhibited inhibition of IKKβ in a single-digit micromolar dose. At the same time, 11 showed promising cytotoxicity against A549 lung cancer cells with IC50 of 0.

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A novel series of 2-phenyl-5-(1,3-diphenyl-1H-pyrazol-4-yl)-1,3,4-oxadiazoles were designed and synthesized for selective COX-2 inhibition with potent anti-inflammatory activity. Among the compounds tested, 9g (2-(3-(4-nitrophenyl)-1-phenyl-1H-pyrazol-4-yl)-5-phenyl-1,3,4-oxadiazole) was found to be the most potent inhibitor of COX-2 with IC50 of 0.31 μM showing promising degree of anti-inflammatory activity in the carrageenan-induced rat paw edema model with ED50 of 74.

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The activation of transcription factors nuclear factor-kappa B (NF-κ B) and cyclooxygenase-2 (COX-2) is critical in cancer; they act synergistically in promoting tumor growth, survival, and resistance to chemotherapy. Thus, combined targeting of NF-κ B and COX-2 present an opportunity for synergistic anticancer efficacy. The ester prodrugs of pentacyclic triterpenoids reduced lantadene A (3), B (4), and its congener 22β-hydroxyoleanonic acid (5) with various non steroidal anti-inflammatory drugs (NSAIDs) present a novel approach.

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The C-3, C-17 and C-22 congeners of pentacyclic triterpenoids reduced lantadene A (3), B (4) and 22β-hydroxyoleanolic acid (5) were synthesized and were tested in vitro for their NF-κB and IKKβ inhibitory potencies and cytotoxicity against A549 lung cancer cells. The lead congeners 12 and 13 showed IC50 of 0.56 and 0.

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The novel 4-(4-oxo-2-arylthiazolidin-3-yl)benzenesulfonamide derivatives were designed and synthesized for selective carbonic anhydrase IX (CA IX) inhibitory activity with anticancer potential. In the CA inhibition assay, 3f was found to be the most potent and selective inhibitor of CA IX with inhibitory constant (K(I)) value of 2.2 nM.

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Nuclear factor-kappaB (NF-κB) has been reported to regulate various genes involved in cancer and inflammation. Accordingly, drugs suppressing or inhibiting NF-κB may possess both anti-inflammatory and anticancer properties. A library of quinolone substituted thiazolidin-4-ones was docked into the active site of NF-κB and the top-ranked 31 compounds were synthesized and evaluated for anti-inflammatory and anticancer activity.

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