548 results on '"Chakravarti R"'
Search Results
102. Tigogenin and ursolic acid from Cestrum diurnum Linn.
- Author
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Chakravarti, R., Datta, Sibani, and Mitra, M.
- Abstract
Copyright of Experientia is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 1964
- Full Text
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103. Triterpenes of Alstonia scholaris (dita-bark).
- Author
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Chakravarti, Mrs, Chakravarti, R., and Ghose, Miss
- Abstract
Copyright of Experientia is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 1957
- Full Text
- View/download PDF
104. Sterol from Aegle marmelos.
- Author
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Chakravarti, R. and Dasgupta, B.
- Abstract
Copyright of Experientia is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 1956
- Full Text
- View/download PDF
105. Atherosclerosis in Macaca mulatta: Histopathological, morphometric, and histochemical studies in aorta and coronary arteries of spontaneous and induced atherosclerosis
- Author
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Chakravarti, R
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- 1976
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106. Triterpenes ofAlstonia scholaris(dita-bark)
- Author
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Chakravarti, Mrs D., Chakravarti, R. N., and Ghose, Miss R.
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- 1957
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107. Efficient Synthesis of 2,3,4-Trisubstituted Quinolines via Friedländer Annulation with Nanoporous Cage-Type Aluminosilicate AlKIT-5 Catalyst
- Author
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Ajayan Vinu, B. V. Subba Reddy, S. M. J. Zaidi, Salem S. Al-Deyab, Rajashree Chakravarti, S. Chauhan, Chauhan, S., Chakravarti, R., Zaidi, S. M. J., Al-Deyab, Salem S., Reddy, B. V. Subba, and Vinu, Ajayan
- Subjects
quinolines ,Annulation ,Nanoporous ,domino reactions ,Organic Chemistry ,Quinoline ,High selectivity ,Condensation ,o-aminoaryl ketones ,nanoporous catalysts ,Catalysis ,chemistry.chemical_compound ,chemistry ,Aluminosilicate ,Organic chemistry ,High surface area - Abstract
2-Aminoaryl ketones undergo smooth Friedländer condensation/annulation with α-methyleneketones on the surface of nanoporous aluminosilicate catalyst to afford the corresponding quinoline derivatives in good yields with high selectivity due to its high surface area, large pore volume, and high acidity. The use of highly acidic and reusable AlKIT-5 catalyst makes the Friedländer annulation simple, convenient, and practical. Refereed/Peer-reviewed
- Published
- 2010
108. Three-dimensional mesoporous cage type aluminosilicate: An efficient catalyst for ring opening of epoxides with aromatic and aliphatic amines
- Author
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Hamid Oveisi, Ajayan Vinu, S. B. Halligudi, Ravindra R. Pal, Pranjal Kalita, Mannepalli Lakshmi Kantam, Rajashree Chakravarti, Chakravarti, R., Oveisi, H., Kalita, P., Pal, R., Halligudi, S. B., Kantam, M. L., and Vinu, Ajayan
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chemistry.chemical_classification ,catalysis ,aluminosilicates ,Epoxide ,General Chemistry ,Condensed Matter Physics ,Heterogeneous catalysis ,Catalysis ,epoxides ,Acid strength ,chemistry.chemical_compound ,Adsorption ,chemistry ,Nucleophile ,β-Amino alcohols ,Mechanics of Materials ,Aluminosilicate ,Organic chemistry ,General Materials Science ,mesoporous ,Mesoporous material - Abstract
Three-dimensional mesoporous aluminosilicate catalysts (AlKIT-5) with cage type porous structure were prepared using Pluronic F127 as a structure-directing agent in a highly acidic medium. The catalysts were characterized by XRD, N2 adsorption, and TPD of NH3. The acidity and the acid strength of the AlKIT-5 were controlled by varying the amount of Al in the silica framework of the mesochannels. Further, the catalysts were utilized for a facile nucleophilic ring opening of epoxides with various aromatic and aliphatic amines under mild reaction condition. The reactions were found to be highly selective and efficient, affording the corresponding β-aminoalcohols in good yield. It was found that the catalyst is recyclable and the activity of the catalyst was not diminished even after several reaction cycles. Refereed/Peer-reviewed
- Published
- 2009
109. High temperature microwave-assisted synthesis and the physico-chemical characterisation of mesoporous crystalline titania
- Author
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Ajayan Mano, Ajayan Vinu, Javaid S. M. Zaidi, Ramasamy Jayavel, Chokkalingam Anand, Salem S. Al-Deyab, Kandasamy Sivakumar, El-Refaie Kenawy, B. Sathyaseelan, Rajashree Chakravarti, Sathyaseelan, B., Anand, C., Mano, A., Zaidi, J., Chakravarti, R., Kenawy, El-Refaie, Al-Deyab, Salem S., Jayavel, R., Sivakumar, K., and Vinu, Ajayan
- Subjects
Anatase ,Materials science ,mesoporous TiO2 ,microwave ,Mineralogy ,Bioengineering ,Condensed Matter Physics ,Nanocrystalline material ,Mesoporous organosilica ,Template reaction ,Adsorption ,Nanocrystal ,Chemical engineering ,Materials Chemistry ,crystalline ,photoluminescence ,Electrical and Electronic Engineering ,Mesoporous material ,High-resolution transmission electron microscopy - Abstract
Mesoporous TiO2 with nanocrystalline architecture has been synthesised by using microwave-assisted high temperature method using polymeric surfactant. The polymeric template was removed by stepwise carbonisation process. The structural order, band structure and the textural parameters of the calcined mesoporous titania were investigated by using numerous sophisticated techniques such as XRD, nitrogen adsorption, HRSEM, UV-Vis DRS and HRTEM. The obtained mesoporous TiO2 material have mesoscopic order, high surface area, crystalline walls and narrow pore size distribution as evident from the XRD and nitrogen adsorption results. Wide-angle X-ray diffraction pattern obtained for calcined mesoporous TiO2 shows that the pore wall of the sample is composed of highly crystalline Ti-O-Ti framework with an anatase phase. The photoluminescence properties of the mesoporous TiO2 was also analysed and the results were discussed in detail. Refereed/Peer-reviewed
- Published
- 2010
110. EXPERIMENTAL STUDY OF AGENTS PROTECTING THE SKIN AGAINST ACUTE RADIATION ULCERATION.
- Author
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Chakravarti, R
- Published
- 1970
111. EXPERIMENTAL STUDY OF POST-IRRADIATION RENAL PATHOLOGY IN RABBITS.
- Author
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Chakravarti, R
- Published
- 1969
112. ON THE PRODUCTION OF CHARGED MESON PAIRS BY NEUTRAL PARTICLES IN COSMIC RAYS
- Author
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Chakravarti, R
- Published
- 1954
113. IRF3 inhibits inflammatory signaling pathways in macrophages to prevent viral pathogenesis.
- Author
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Chakravarty S, Varghese M, Fan S, Taylor RT, Chakravarti R, and Chattopadhyay S
- Subjects
- Animals, Mice, NF-kappa B metabolism, Lung virology, Lung pathology, Lung immunology, Lung metabolism, Interferon Regulatory Factor-3 metabolism, Interferon Regulatory Factor-3 genetics, Macrophages immunology, Macrophages metabolism, Signal Transduction, Inflammation metabolism, Inflammation immunology, Inflammation pathology, Mice, Knockout
- Abstract
Viral inflammation contributes to pathogenesis and mortality during respiratory virus infections. IRF3, a critical component of innate antiviral immune responses, interacts with pro-inflammatory transcription factor NF-κB, and inhibits its activity. This mechanism helps suppress inflammatory gene expression in virus-infected cells and mice. We evaluated the cells responsible for IRF3-mediated suppression of viral inflammation using newly engineered conditional Irf3
Δ/Δ mice. Irf3Δ/Δ mice, upon respiratory virus infection, showed increased susceptibility and mortality. Irf3 deficiency caused enhanced inflammatory gene expression, lung inflammation, immunopathology, and damage, accompanied by increased infiltration of pro-inflammatory macrophages. Deletion of Irf3 in macrophages ( Irf3MKO ) displayed, similar to Irf3Δ/Δ mice, increased inflammatory responses, macrophage infiltration, lung damage, and lethality, indicating that IRF3 in these cells suppressed lung inflammation. RNA-seq analyses revealed enhanced NF-κB-dependent gene expression along with activation of inflammatory signaling pathways in infected Irf3MKO lungs. Targeted analyses revealed activated MAPK signaling in Irf3MKO lungs. Therefore, IRF3 inhibited inflammatory signaling pathways in macrophages to prevent viral inflammation and pathogenesis.- Published
- 2024
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114. A Lipophilic Salt Form to Enhance the Lipid Solubility and Certain Biopharmaceutical Properties of Lapatinib.
- Author
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Singh N, Chakravarti R, Das A, Gupta S, Ghosh D, and Datta P
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- Humans, Lipids chemistry, Salts chemistry, Biological Availability, Hydrogen-Ion Concentration, Chemistry, Pharmaceutical methods, Antineoplastic Agents chemistry, Antineoplastic Agents pharmacology, Antineoplastic Agents administration & dosage, Drug Liberation, Solubility, Lapatinib chemistry, Excipients chemistry
- Abstract
Lapatinib (LTP) commercially available as lapatinib ditosylate (LTP-DTS) salt is the only drug approved for the treatment of HER-positive metastatic breast cancer. A low and pH-dependent solubility results in poor and variable oral bioavailability, thus driving significant interest in molecular modification and formulation strategies of the drug. Furthermore, due to very high crystallinity, LTP and LTP-DTS have low solubility in lipid excipients, making it difficult to be delivered by lipid-based carrier systems. Thus, the present work reports a new salt form of LTP with a docusate counterion to enhance the pharmaceutical properties of the drug (LTP-DOC). NMR spectra showed a downfield shift of the methylene singlet proton from 3.83 and 4.41 ppm, indicating a lowering of electron density on the adjacent nitrogen atom and confirming the formation of amine-sulfonyl salt through the specified basic nitrogen center located adjacent to the furan ring. PXRD diffractograms of LTP-DOC indicated a reduced crystallinity of the prepared salt. The dissolution, equilibrium solubility, lipid excipient solubility, partitioning coefficient, distribution coefficient, tabletability, and in vitro cytotoxicity of the lipophilic salt of LTP were investigated. The equilibrium solubility data showed that LTP-DOC possesses a pH-independent solubility profile in the pH range of 3.5 to 7.4 with a 3.14 times higher permeability coefficient than commercial ditosylate salt. Furthermore, the prepared LTP-DOC salts showed twice higher log P than the free base and 8 times higher than LTP-DTS. The prepared LTP-DOC was found to have 4- to 9-fold higher solubility in lipid excipients like Capmul MCM C8 and Maisine CC compared to the ditosylate salt. The LTP-DOC salt was tabletable and showed approximately 1.2 times lower dissolution than commercial ditosylate salt, indicating extended-release behavior. A cytotoxicity study of LTP-DOC salt showed an approximately 2.5 times lower IC
50 value than the LTP-free base and 1.7 times lower than commercial ditosylate salt with an approximately 3 times higher selectivity index. The investigations strongly indicate a high translational potential of the prepared salt form in maintaining solubility-lipophilicity interplay, enhancing the drug's bioavailability, and developing lipidic formulations.- Published
- 2024
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115. A poly-δ-decalactone (PDL) based nanoemulgel for topical delivery of ketoconazole and eugenol against Candida albicans .
- Author
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Dubey P, Kumar A, Vaiphei KK, Basrani S, Jadhav A, Wilen CE, Rosenholm JM, Bansal KK, Chakravarti R, Ghosh D, and Gulbake A
- Abstract
This study aimed to investigate the potential of poly-δ-decalactone (PDL) and a block copolymer (methoxy-poly(ethylene glycol)- b -poly-δ-decalactone (mPEG- b -PDL)) in the topical delivery of ketoconazole (KTZ) and eugenol (EUG) against Candida albicans . The nanoemulsion (NE) was studied for its significant factors and was optimized using the design of experiments (DOE) methodologies. A simple robust nanoprecipitation method was employed to successfully produce a nanoemulsion (KTZ-EUG-NE). The spherical globules exhibited rough surfaces, explaining the adsorption of mPEG- b -PDL onto PDL. The sustained drug release effects were governed by the amorphous nature of PDL. KTZ-EUG-NE was further used to develop a 1% w/v Carbopol-940-based nanoemulgel (KTZ-EUG-NE gel). The optimal rheological and spreadability properties of the developed nanoemulgel explain the ease of topical applications. Ex vivo permeation and retention studies confirmed the accumulation of KTZ-EUG-NE at different layers of the skin when applied topically. The cytotoxicity of the developed NE in human keratinocyte (HaCaT) cells demonstrated the utility of this newly explored nanocarrier in reducing the cell toxicity of KTZ. The higher antifungal activities of KTZ-EUG-NE at 19.23-fold lower concentrations for planktonic growth and 4-fold lower concentrations for biofilm formation than coarse drugs explain the effectiveness of the developed NE., Competing Interests: The authors report no conflict of interest related to the manuscript., (This journal is © The Royal Society of Chemistry.)
- Published
- 2024
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116. A mechanistic study on the tolerance of PAM distal end mismatch by SpCas9.
- Author
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Dey D, Chakravarti R, Bhattacharjee O, Majumder S, Chaudhuri D, Ahmed KT, Roy D, Bhattacharya B, Arya M, Gautam A, Singh R, Gupta R, Ravichandiran V, Chattopadhyay D, Ghosh A, Giri K, Roy S, and Ghosh D
- Subjects
- Humans, DNA chemistry, DNA metabolism, Molecular Dynamics Simulation, RNA chemistry, RNA metabolism, RNA, Guide, CRISPR-Cas Systems metabolism, RNA, Guide, CRISPR-Cas Systems chemistry, HEK293 Cells, Gene Editing, CRISPR-Cas Systems, Base Pair Mismatch, CRISPR-Associated Protein 9 metabolism, CRISPR-Associated Protein 9 genetics, CRISPR-Associated Protein 9 chemistry
- Abstract
The therapeutic application of CRISPR-Cas9 is limited due to its off-target activity. To have a better understanding of this off-target effect, we focused on its mismatch-prone PAM distal end. The off-target activity of SpCas9 depends directly on the nature of mismatches, which in turn results in deviation of the active site of SpCas9 due to structural instability in the RNA-DNA duplex strand. In order to test the hypothesis, we designed an array of mismatched target sites at the PAM distal end and performed in vitro and cell line-based experiments, which showed a strong correlation for Cas9 activity. We found that target sites having multiple mismatches in the 18th to 15th position upstream of the PAM showed no to little activity. For further mechanistic validation, Molecular Dynamics simulations were performed, which revealed that certain mismatches showed elevated root mean square deviation values that can be attributed to conformational instability within the RNA-DNA duplex. Therefore, for successful prediction of the off-target effect of SpCas9, along with complementation-derived energy, the RNA-DNA duplex stability should be taken into account., Competing Interests: Conflict of interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2024
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117. Non-transcriptional IRF7 interacts with NF-κB to inhibit viral inflammation.
- Author
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Fan S, Popli S, Chakravarty S, Chakravarti R, and Chattopadhyay S
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- Animals, Humans, Mice, HEK293 Cells, Inflammation genetics, Sendai virus physiology, Transcription Factor RelA genetics, Transcription Factor RelA immunology, Virus Replication, Mutation, Gene Expression Regulation genetics, Murine hepatitis virus physiology, Coronavirus Infections immunology, Respirovirus Infections immunology, Interferon Regulatory Factor-7 genetics, Interferon Regulatory Factor-7 immunology, NF-kappa B genetics, NF-kappa B immunology
- Abstract
Interferon (IFN) regulatory factors (IRF) are key transcription factors in cellular antiviral responses. IRF7, a virus-inducible IRF, expressed primarily in myeloid cells, is required for transcriptional induction of interferon α and antiviral genes. IRF7 is activated by virus-induced phosphorylation in the cytoplasm, leading to its translocation to the nucleus for transcriptional activity. Here, we revealed a nontranscriptional activity of IRF7 contributing to its antiviral functions. IRF7 interacted with the pro-inflammatory transcription factor NF-κB-p65 and inhibited the induction of inflammatory target genes. Using knockdown, knockout, and overexpression strategies, we demonstrated that IRF7 inhibited NF-κB-dependent inflammatory target genes, induced by virus infection or toll-like receptor stimulation. A mutant IRF7, defective in transcriptional activity, interacted with NF-κB-p65 and suppressed NF-κB-induced gene expression. A single-action IRF7 mutant, active in anti-inflammatory function, but defective in transcriptional activity, efficiently suppressed Sendai virus and murine hepatitis virus replication. We, therefore, uncovered an anti-inflammatory function for IRF7, independent of transcriptional activity, contributing to the antiviral response of IRF7., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2024
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118. Structural Features and Physiological Associations of Human 14-3-3ζ Pseudogenes.
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Lughmani H, Patel H, and Chakravarti R
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- Humans, Exons genetics, Genome, Human, 14-3-3 Proteins genetics, 14-3-3 Proteins metabolism, Pseudogenes genetics
- Abstract
There are about 14,000 pseudogenes that are mutated or truncated sequences resembling functional parent genes. About two-thirds of pseudogenes are processed, while others are duplicated. Although initially thought dead, emerging studies indicate they have functional and regulatory roles. We study 14-3-3ζ, an adaptor protein that regulates cytokine signaling and inflammatory diseases, including rheumatoid arthritis, cancer, and neurological disorders. To understand how 14-3-3ζ (gene symbol YWHAZ) performs diverse functions, we examined the human genome and identified nine YWHAZ pseudogenes spread across many chromosomes. Unlike the 32 kb exon-to-exon sequence in YWHAZ, all pseudogenes are much shorter and lack introns. Out of six, four YWHAZ exons are highly conserved, but the untranslated region (UTR) shows significant diversity. The putative amino acid sequence of pseudogenes is 78-97% homologous, resulting in striking structural similarities with the parent protein. The OMIM and Decipher database searches revealed chromosomal loci containing pseudogenes are associated with human diseases that overlap with the parent gene. To the best of our knowledge, this is the first report on pseudogenes of the 14-3-3 family protein and their implications for human health. This bioinformatics-based study introduces a new insight into the complexity of 14-3-3ζ's functions in biology.
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- 2024
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119. Differences in Responses of Immunosuppressed Kidney Transplant Patients to Moderna mRNA-1273 versus Pfizer-BioNTech.
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Bekbolsynov D, Waack A, Buskey C, Bhadkamkar S, Rengel K, Petersen W, Brown ML, Sparkle T, Kaw D, Syed FJ, Chattopadhyay S, Chakravarti R, Khuder S, Mierzejewska B, Rees M, and Stepkowski S
- Abstract
Immunosuppressed kidney transplant (KT) recipients produce a weaker response to COVID-19 vaccination than immunocompetent individuals. We tested antiviral IgG response in 99 KT recipients and 66 healthy volunteers who were vaccinated with mRNA-1273 Moderna or BNT162b2 Pfizer-BioNTech vaccines. A subgroup of participants had their peripheral blood leukocytes (PBLs) evaluated for the frequency of T helper 1 (Th1) cells producing IL-2, IFN-γ and/or TNF-α, and IL-10-producing T-regulatory 1 (Tr) cells. Among KT recipients, 45.8% had anti-SARS-CoV-2 IgG compared to 74.1% of healthy volunteers ( p = 0.009); also, anti-viral IgG levels were lower in recipients than in volunteers ( p = 0.001). In terms of non-responders (≤2000 U/mL IgG), Moderna's group had 10.8% and Pfizer-BioNTech's group had 34.3% of non-responders at 6 months ( p = 0.023); similarly, 15.7% and 31.3% were non-responders in Moderna and Pfizer-BioNTech groups at 12 months, respectively ( p = 0.067). There were no non-responders among controls. Healthy volunteers had higher Th1 levels than KT recipients, while Moderna produced a higher Th1 response than Pfizer-BioNTech. In contrast, the Pfizer-BioNTech vaccine induced a higher Tr1 response than the Moderna vaccine ( p < 0.05); overall, IgG levels correlated with Th1(fT
TNF-α )/Tr1(fTIL-10 ) ratios. We propose that the higher number of non-responders in the Pfizer-BioNTech group than the Moderna group was caused by a more potent activity of regulatory Tr1 cells in KT recipients vaccinated with the Pfizer-BioNTech vaccine.- Published
- 2024
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120. Exploration of Variable Solvent Directed Self-Healable Supramolecular M(II)-Metallogels (M = Co, Ni, Zn) of Azelaic Acid: Investigating Temperature-Dependent Ion Conductivity and Antibacterial Efficiency.
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Pal I, Majumdar S, Lepcha G, Ahmed KT, Yatirajula SK, Bhattacharya S, Chakravarti R, Bhattacharya B, Biswas SR, and Dey B
- Subjects
- Humans, Solvents, Temperature, HEK293 Cells, Anti-Bacterial Agents pharmacology, Zinc pharmacology, Salts, Neuroblastoma
- Abstract
Molecular self-assembly assisted self-healing supramolecular metallogels of azelaic acid with cobalt(II)-, nickel(II)-, and zinc(II)-based metal acetate salts were successfully fabricated. Individually, N , N '-dimethylformamide and dimethyl sulfoxide were immobilized within these distinctly synthesized soft-scaffolds of metallogels to attain their semisolid viscoelastic nature. Rheological experiments such as amplitude sweep, frequency sweep, and thixotropic measurements were executed for these metallogels to ratify their gel features. The different extents of supramolecular interactions operating within these solvent-directed metallogels were clearly reflected in terms of their distinct morphological patterns as investigated through field emission scanning electron microscopy. Comparative infrared (IR) spectral properties of metallogels along with individual metal salts and azelaic acid were analyzed. These experimental data clearly depict the significant shifting of Fourier transform (FT)-IR peaks of xerogel samples of different metallogels from the gel-forming precursors. The networks present within the soft-scaffold are evidently illustrated by the electrospray ionization-mass experimental data. The temperature-dependent ionic conductivity studies with these solvent-directed versatile metallogel systems were investigated through impedance spectroscopy. The temperature-dependent impedance spectroscopic studies clearly demonstrate that the ion-transportation within the gel matrix depends not only on the types of cations but also on the dielectric properties of the immobilized solvents. The antipathogenic effect of these metallogel systems has also been explored by testing their effectiveness against human pathogenic Gram-negative bacteria Klebsiella pneumoniae (MTCC 109) and Vibrio parahemolyticus , and Gram-positive bacteria like Bacillus cereus (MTCC 1272). These gel soft-scaffolds show no significant cytotoxicity against both the human neuroblastoma cell line-SH-SY5Y and the human embryonic kidney cell line-HEK 293.
- Published
- 2023
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121. Ohio Coronavirus Wastewater Monitoring Network: Implementation of Statewide Monitoring for Protecting Public Health.
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Bohrerova Z, Brinkman NE, Chakravarti R, Chattopadhyay S, Faith SA, Garland J, Herrin J, Hull N, Jahne M, Kang DW, Keely SP, Lee J, Lemeshow S, Lenhart J, Lytmer E, Malgave D, Miao L, Minard-Smith A, Mou X, Nagarkar M, Quintero A, Savona FDR, Senko J, Slonczewski JL, Spurbeck RR, Sovic MG, Taylor RT, Weavers LK, and Weir M
- Subjects
- Humans, Ohio, Pandemics prevention & control, Public Health, SARS-CoV-2, Wastewater, COVID-19 epidemiology, COVID-19 prevention & control
- Abstract
Context: Prior to the COVID-19 pandemic, wastewater influent monitoring for tracking disease burden in sewered communities was not performed in Ohio, and this field was only on the periphery of the state academic research community., Program: Because of the urgency of the pandemic and extensive state-level support for this new technology to detect levels of community infection to aid in public health response, the Ohio Water Resources Center established relationships and support of various stakeholders. This enabled Ohio to develop a statewide wastewater SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) monitoring network in 2 months starting in July 2020., Implementation: The current Ohio Coronavirus Wastewater Monitoring Network (OCWMN) monitors more than 70 unique locations twice per week, and publicly available data are updated weekly on the public dashboard., Evaluation: This article describes the process and decisions that were made during network initiation, the network progression, and data applications, which can inform ongoing and future pandemic response and wastewater monitoring., Discussion: Overall, the OCWMN established wastewater monitoring infrastructure and provided a useful tool for public health professionals responding to the pandemic., Competing Interests: The authors declare that they have no conflicts of interests to disclose., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)
- Published
- 2023
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122. Interferon-stimulated gene TDRD7 interacts with AMPK and inhibits its activation to suppress viral replication and pathogenesis.
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Chakravarty S, Subramanian G, Popli S, Veleeparambil M, Fan S, Chakravarti R, and Chattopadhyay S
- Subjects
- Animals, Mice, AMP-Activated Protein Kinases metabolism, Virus Replication genetics, Antiviral Agents pharmacology, Immunity, Innate, Ribonucleoproteins genetics, Interferons metabolism, Virus Diseases
- Abstract
Importance: Virus infection triggers induction of interferon (IFN)-stimulated genes (ISGs), which ironically inhibit viruses themselves. We identified Tudor domain-containing 7 (TDRD7) as a novel antiviral ISG, which inhibits viral replication by interfering with autophagy pathway. Here, we present a molecular basis for autophagy inhibitory function of TDRD7. TDRD7 interacted with adenosine monophosphate (AMP)-activated protein kinase (AMPK), the kinase that initiates autophagy, to inhibit its activation. We identified domains required for the interaction; deleting AMPK-interacting domain blocked antiAMPK and antiviral activities of TDRD7. We used primary cells and mice to evaluate the TDRD7-AMPK antiviral pathway. TDRD7-deficient primary mouse cells exhibited enhanced AMPK activation and viral replication. Finally, TDRD7 knockout mice showed increased susceptibility to respiratory virus infection. Therefore, our study revealed a new antiviral pathway of IFN and its contribution to host response. Our results have therapeutic potential; a TDRD7-derived peptide may be an effective AMPK inhibitor with application as antiviral agent., Competing Interests: The authors declare no conflict of interest.
- Published
- 2023
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123. Inflammatory Control of Viral Infection.
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Chakravarty S, Chakravarti R, and Chattopadhyay S
- Subjects
- Humans, NF-kappa B metabolism, Inflammation, Immunity, Innate, Signal Transduction, Virus Diseases
- Abstract
Inflammatory responses during virus infection differentially impact the host. Managing inflammatory responses is essential in controlling viral infection and related diseases. Recently, we identified a cellular anti-inflammatory mechanism, RIKA (Repression of IRF3-mediated inhibition of NF-κB activity), which controls viral inflammation and pathogenesis. The RIKA function of IRF3 may be explored further in other inflammatory diseases beyond viral infection.
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- 2023
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124. IRF3 inhibits nuclear translocation of NF-κB to prevent viral inflammation.
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Popli S, Chakravarty S, Fan S, Glanz A, Aras S, Nagy LE, Sen GC, Chakravarti R, and Chattopadhyay S
- Subjects
- Active Transport, Cell Nucleus, Animals, Cell Nucleus metabolism, Gene Expression, Interferon-beta genetics, Mice, Sendai virus, Immunity, Innate, Interferon Regulatory Factor-3 genetics, Interferon Regulatory Factor-3 metabolism, NF-kappa B metabolism, Pneumonia, Viral genetics, Pneumonia, Viral immunology
- Abstract
Interferon (IFN) regulatory factor 3 (IRF3) is a transcription factor activated by phosphorylation in the cytoplasm of a virus-infected cell; by translocating to the nucleus, it induces transcription of IFN-β and other antiviral genes. We have previously reported IRF3 can also be activated, as a proapoptotic factor, by its linear polyubiquitination mediated by the RIG-I pathway. Both transcriptional and apoptotic functions of IRF3 contribute to its antiviral effect. Here, we report a nontranscriptional function of IRF3, namely, the repression of IRF3-mediated NF-κB activity (RIKA), which attenuated viral activation of NF-κB and the resultant inflammatory gene induction. In Irf3
-/- mice, consequently, Sendai virus infection caused enhanced inflammation in the lungs. Mechanistically, RIKA was mediated by the direct binding of IRF3 to the p65 subunit of NF-κB in the cytoplasm, which prevented its nuclear import. A mutant IRF3 defective in both the transcriptional and the apoptotic activities was active in RIKA and inhibited virus replication. Our results demonstrated IRF3 deployed a three-pronged attack on virus replication and the accompanying inflammation.- Published
- 2022
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125. SARS-CoV-2 Monitoring in Wastewater Reveals Novel Variants and Biomarkers of Infection.
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McGowan J, Borucki M, Omairi H, Varghese M, Vellani S, Chakravarty S, Fan S, Chattopadhyay S, Siddiquee M, Thissen JB, Mulakken N, Moon J, Kimbrel J, Tiwari AK, Taylor RT, Kang DW, Jaing C, Chakravarti R, and Chattopadhyay S
- Subjects
- Biomarkers, Humans, Pandemics, RNA, RNA, Viral, Wastewater, COVID-19 epidemiology, SARS-CoV-2 genetics
- Abstract
Wastewater-based epidemiology (WBE) is a popular tool for the early indication of community spread of infectious diseases. WBE emerged as an effective tool during the COVID-19 pandemic and has provided meaningful information to minimize the spread of infection. Here, we present a combination of analyses using the correlation of viral gene copies with clinical cases, sequencing of wastewater-derived RNA for the viral mutants, and correlative analyses of the viral gene copies with the bacterial biomarkers. Our study provides a unique platform for potentially using the WBE-derived results to predict the spread of COVID-19 and the emergence of new variants of concern. Further, we observed a strong correlation between the presence of SARS-CoV-2 and changes in the microbial community of wastewater, particularly the significant changes in bacterial genera belonging to the families of Lachnospiraceae and Actinomycetaceae . Our study shows that microbial biomarkers could be utilized as prediction tools for future infectious disease surveillance and outbreak responses. Overall, our comprehensive analyses of viral spread, variants, and novel bacterial biomarkers will add significantly to the growing body of literature on WBE and COVID-19.
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- 2022
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126. Cas13d: A New Molecular Scissor for Transcriptome Engineering.
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Gupta R, Ghosh A, Chakravarti R, Singh R, Ravichandiran V, Swarnakar S, and Ghosh D
- Abstract
The discovery of Clustered Regularly Interspaced Palindromic Repeats (CRISPR) and its associated Cas endonucleases in bacterial and archaeal species allowed scientists to modify, utilized, and revolutionize this tool for genetic alterations in any species. Especially the type II CRISPR-Cas9 system has been extensively studied and utilized for precise and efficient DNA manipulation in plant and mammalian systems over the past few decades. Further, the discovery of the type V CRISPR-Cas12 (Cpf1) system provides more flexibility and precision in DNA manipulation in prokaryotes, plants, and animals. However, much effort has been made to employ and utilize the above CRISPR tools for RNA manipulation but the ability of Cas9 and Cas12 to cut DNA involves the nuisance of off-target effects on genes and thus may not be employed in all RNA-targeting applications. Therefore, the search for new and diverse Cas effectors which can precisely detect and manipulate the targeted RNA begins and this led to the discovery of a novel RNA targeting class 2, type VI CRISPR-Cas13 system. The CRISPR-Cas13 system consists of single RNA-guided Cas13 effector nucleases that solely target single-stranded RNA (ssRNA) in a programmable way without altering the DNA. The Cas13 effectors family comprises four subtypes (a-d) and each subtype has distinctive primary sequence divergence except the two consensuses Higher eukaryotes and prokaryotes nucleotide-binding domain (HEPN) that includes RNase motifs i.e. R-X4-6-H. These two HEPN domains are solely responsible for executing targetable RNA cleavage activity with high efficiency. Further, recent studies have shown that Cas13d exhibits higher efficiency and specificity in cleaving targeted RNA in the mammalian system compared to other Cas13 endonucleases of the Cas13 enzyme family. In addition to that, Cas13d has shown additional advantages over other Cas13 variants, structurally as well as functionally which makes it a prominent and superlative tool for RNA engineering and editing. Therefore considering the advantages of Cas13d over previously characterized Cas13 subtypes, in this review, we encompass the structural and mechanistic properties of type VI CRISPR-Cas13d systems, an overview of the current reported various applications of Cas13d, and the prospects to improve Cas13d based tools for diagnostic and therapeutic purposes., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Gupta, Ghosh, Chakravarti, Singh, Ravichandiran, Swarnakar and Ghosh.)
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- 2022
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127. Autophagy in Virus Infection: A Race between Host Immune Response and Viral Antagonism.
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Chawla K, Subramanian G, Rahman T, Fan S, Chakravarty S, Gujja S, Demchak H, Chakravarti R, and Chattopadhyay S
- Abstract
Virus-infected cells trigger a robust innate immune response and facilitate virus replication. Here, we review the role of autophagy in virus infection, focusing on both pro-viral and anti-viral host responses using a select group of viruses. Autophagy is a cellular degradation pathway operated at the basal level to maintain homeostasis and is induced by external stimuli for specific functions. The degradative function of autophagy is considered a cellular anti-viral immune response. However, autophagy is a double-edged sword in viral infection; viruses often benefit from it, and the infected cells can also use it to inhibit viral replication. In addition to viral regulation, autophagy pathway proteins also function in autophagy-independent manners to regulate immune responses. Since viruses have co-evolved with hosts, they have developed ways to evade the anti-viral autophagic responses of the cells. Some of these mechanisms are also covered in our review. Lastly, we conclude with the thought that autophagy can be targeted for therapeutic interventions against viral diseases., Competing Interests: Conflicts of Interest: The authors declare that they have no conflict of interest with the contents of this article.
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- 2022
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128. An insight into SARS-CoV-2 structure, pathogenesis, target hunting for drug development and vaccine initiatives.
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Ghosh A, Kar PK, Gautam A, Gupta R, Singh R, Chakravarti R, Ravichandiran V, Ghosh Dastidar S, Ghosh D, and Roy S
- Abstract
SARS-CoV-2, the virus responsible for the COVID-19 pandemic, has been confirmed to be a new coronavirus having 79% and 50% similarity with SARS-CoV and MERS-CoV, respectively. For a better understanding of the features of the new virus SARS-CoV-2, we have discussed a possible correlation between some unique features of the genome of SARS-CoV-2 in relation to pathogenesis. We have also reviewed structural druggable viral and host targets for possible clinical application if any, as cases of reinfection and compromised protection have been noticed due to the emergence of new variants with increased infectivity even after vaccination. We have also discussed the types of vaccines that are being developed against SARS-CoV-2. In this review, we have tried to give a brief overview of the fundamental factors of COVID-19 research like basic virology, virus variants and the newly emerging techniques that can be applied to develop advanced treatment strategies for the management of COVID-19 disease., Competing Interests: There is no conflict of interest to declare., (This journal is © The Royal Society of Chemistry.)
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- 2022
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129. Effects of antibiotic treatment on microbiota, viral transmission and viral pathogenesis of MoMuLV ts1 infected BALB/c mice.
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Okonta H, Cheng X, Chakravarti R, and Duggan J
- Subjects
- Animals, Female, Mice, Mice, Inbred BALB C, Anti-Bacterial Agents pharmacology, Gastrointestinal Microbiome drug effects, Moloney murine leukemia virus metabolism, Retroviridae Infections metabolism, Retroviridae Infections transmission
- Abstract
The effects of normal and altered intestinal microbiota on murine retroviral transmission via the gastrointestinal tract (GIT) are diverse. The role of orally administered antibiotic treatment (ABX) on viral transmission, GIT microbial dysbiosis and subsequent pathogenesis of Moloney Murine Leukemia virus-temperature sensitive 1 (ts1) on BALB/c mice were studied. BALB/c mice were divided into four groups: ABXts1-Treatment/Infection;ABX-Treatment/No infection;ts1-No treatment/Infection;Ctrl (control)-No treatment/No infection. ABXts1 and ABX groups showed a significant phylogenetic shift (ANOSIM p-value = 0.001) in alpha and beta diversity comparisons for microbial community composition compared to Ctrl group. Mice in the ABXts1 and ABX groups showed megacolon compared to ts1 and Ctrl groups; ABXts1 and ts1 groups showed hepatosplenomegaly, thymus enlargement, and mesenteric lymphadenopathy compared to ABX and Ctrl groups. Ctrl group had no abnormal manifestations. ABX treatment and ts1 infection uniquely affect microbial community when compared to control: ABXts1 and ABX groups significantly reduce microbiome diversity by over 80% and ts1 group by over 30%. ABXts1 and ts1 groups' viral load and clinical manifestations of infection were comparable; antibiotic treatment did not notably affect ts1 infection. Transmission and pathophysiology of ts1 infection were not significantly altered by the microbial composition of the GI tract, but ts1 viral infection did result in microbial dysbiosis independent of antibiotic treatment., Competing Interests: The authors have declared that no competing interests exist.
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- 2022
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130. A Review on the Current Status of Homeopathy in the Clinical Manage-ment of Cancer.
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Tangelloju A, Chakravarti R, Singh R, Bhattacharya B, Ghosh A, Bhutia SK, Ravichandiran V, and Ghosh D
- Subjects
- Humans, Homeopathy, Neoplasms therapy
- Abstract
Homeopathy is a widely practiced alternate system of medicine around the world that employs small doses of various medicines to promote auto-regulation and self-healing. It is among the most commonly used alternative approaches in cancer and other diseases and alternative therapeutic systems. It is widely used as palliative and as supportive therapy in cancer patients. Few cases have been reported on patients using homeopathy after surgery, radiotherapy, and chemotherapy, generally for overcoming side effects. The dose of Homoeopathic medicines and their mechanism of action in cancer has also been documented, while clinical trials on the effects of Homoeopathy in cancer treatment are rare. It is found that the anticancer potential of homeopathic medicines is reported for different cancer types, which show their efficacy through apoptosis and immune system modulation. Homeopathic treatment is an add-on to conventional therapy, with almost no interaction with the conventional drugs due to the small dose, and is largely attributed to improving lives by providing symptomatic relief, increasing survival time and boosting patient immunity. This review explores the accountability of the homeopathic system of medicine by highlighting some of the most commonly used homeopathic drugs for different types of cancers., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)
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- 2022
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131. Autophagic checks and balances of cellular immune responses.
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Chakravarty S, Fan S, Chakravarti R, and Chattopadhyay S
- Abstract
IRF3 (interferon regulatory factor 3) is a critical component of the antiviral innate immune response. IRF3 deficiency causes detrimental effects to the host during virus infection. Dysregulation of IRF3 functions is associated with viral, inflammatory, and hepatic diseases. Both transcriptional and pro-apoptotic activities of IRF3 are involved in the exacerbated inflammation and apoptosis in liver injury induced by ethanol and high-fat diets. Therefore, regulation of IRF3 activities has consequences, and it is a potential therapeutic target for infectious and inflammatory diseases. We recently revealed that IRF3 is degraded by a small molecule, auranofin, by activating the cellular macroautophagy/autophagy pathway. Autophagy is a catabolic pathway that contributes to cellular homeostasis and antiviral host defense. Degradation of IRF3 by autophagy may be a novel strategy used by the viruses to their benefit. In addition, IRF3 functions are harmful in other diseases, including liver injury and bacterial infection. A better understanding of the role of autophagy in regulating IRF3 functions has significant implications in developing therapeutic strategies. Therefore, autophagy provides checks and balances in the innate immune response.
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- 2022
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132. A Short Review on Glucogallin and its Pharmacological Activities.
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Khan AN, Singh R, Bhattacharya A, Chakravarti R, Roy S, Ravichandiran V, and Ghosh D
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- Humans, Antioxidants pharmacology, Hypoglycemic Agents pharmacology, Esters, Free Radicals, Hydrolyzable Tannins pharmacology, Hydrolyzable Tannins metabolism, Biological Products
- Abstract
Plant derived natural products have multifaceted beneficial roles in human pathophysiology. Plant secondary metabolites have been used as an adjunct medicine for a long time and β- Glucogallin is one such pharmaceutically important plant derived natural product. Β-glucogallin (1-O-galloyl-β-d-glucopyranose), a plant-derived polyphenolic ester, is regarded as the primary metabolite in the biosynthesis of hydrolyzable tannins. It is majorly found in amla, pomegranate, strawberry etc. Owing to its free radical scavenging properties, β-glucogallin (BG) is believed to protect against several diseases like diabetes and related complications like retinopathy, glaucoma, inflammation, hepatic damage, skin damage from UV, etc. Several semisynthetic derivatives of β-Glucogallin are being developed, which have better pharmacokinetic and pharmacodynamic parameters than β-glucogallin. Studies have shown the prophylactic role of β-Glucogallin in developing defence mechanisms against the advent and progression of certain diseases. β- glucogallin formulations have shown a positive effect as a neutraceutical. In this manuscript, we have discussed β-glucogallin, its natural sources, biosynthetic pathways, its semi-synthetic derivatives, and the plethora of its pharmacological activities like antioxidant-antiinflammatory, antidiabetic, cataract-preventing, anti glaucoma, and UV protectant. We have also highlighted various biological pathways, which are modulated by β-glucogallin. The manuscript will convey the importance of β-glucogallin as a compound of natural origin, having multifaceted health benefits., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)
- Published
- 2022
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133. A Review on CRISPR-mediated Epigenome Editing: A Future Directive for Therapeutic Management of Cancer.
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Chakravarti R, Lenka SK, Gautam A, Singh R, Ravichandiran V, Roy S, and Ghosh D
- Subjects
- CRISPR-Cas Systems, DNA Methylation, Epigenesis, Genetic, Epigenome, Histones metabolism, Humans, Obesity, Transcription Factors metabolism, Diabetes Mellitus, Type 2 genetics, Diabetes Mellitus, Type 2 therapy, Neoplasms genetics, Neoplasms therapy
- Abstract
Recent studies have shed light on the role of epigenetic marks in certain diseases like cancer, type II diabetes mellitus (T2DM), obesity, and cardiovascular dysfunction, to name a few. Epigenetic marks like DNA methylation and histone acetylation are randomly altered in the disease state. It has been seen that methylation of DNA and histones can result in down-regulation of gene expression, whereas histone acetylation, ubiquitination, and phosphorylation are linked to enhanced expression of genes. How can we precisely target such epigenetic aberrations to prevent the advent of diseases? The answer lies in the amalgamation of the efficient genome editing technique, CRISPR, with certain effector molecules that can alter the status of epigenetic marks as well as employ certain transcriptional activators or repressors. In this review, we have discussed the rationale of epigenetic editing as a therapeutic strategy and how CRISPR-Cas9 technology coupled with epigenetic effector tags can efficiently edit epigenetic targets. In the later part, we have discussed how certain epigenetic effectors are tagged with dCas9 to elicit epigenetic changes in cancer. Increased interest in exploring the epigenetic background of cancer and non-communicable diseases like type II diabetes mellitus and obesity accompanied with technological breakthroughs has made it possible to perform large-scale epigenome studies., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)
- Published
- 2022
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134. Autophagic degradation of IRF3 induced by the small-molecule auranofin inhibits its transcriptional and proapoptotic activities.
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Glanz A, Chakravarty S, Fan S, Chawla K, Subramanian G, Rahman T, Walters D, Chakravarti R, and Chattopadhyay S
- Subjects
- Animals, Humans, Interferon Regulatory Factor-3 genetics, Mice, RAW 264.7 Cells, Apoptosis drug effects, Auranofin pharmacology, Autophagy drug effects, Interferon Regulatory Factor-3 metabolism, Proteolysis drug effects, Transcription, Genetic drug effects
- Abstract
The ubiquitously expressed transcription factor interferon (IFN) regulatory factor 3 (IRF3) is critical for the induction of antiviral genes, e.g., type-I IFN. In addition to its transcriptional function, IRF3 also activates a nontranscriptional, proapoptotic signaling pathway. While the proapoptotic function of IRF3 protects against viral infections, it is also involved in harmful immune responses that trigger hepatocyte cell death and promote liver disease. Thus, we hypothesized that a small-molecule inhibitor of the proapoptotic activity of IRF3 could alleviate fatty-acid-induced hepatocyte cell death. We conducted a high-throughput screen, which identified auranofin as a small-molecule inhibitor of the proapoptotic activity of IRF3. In addition to the nontranscriptional apoptotic pathway, auranofin also inhibited the transcriptional activity of IRF3. Using biochemical and genetic tools in human and mouse cells, we uncovered a novel mechanism of action for auranofin, in which it induces cellular autophagy to degrade IRF3 protein, thereby suppressing IRF3 functions. Autophagy-deficient cells were unable to degrade IRF3 upon auranofin treatment, suggesting that the autophagic degradation of IRF3 is a novel approach to regulate IRF3 activities. Using a physiologically relevant in vitro model, we demonstrated that auranofin inhibited fatty-acid-induced apoptotic cell death of hepatocytes. In summary, auranofin is a novel inhibitor of IRF3 functions and may represent a potential therapeutic option in diseases where IRF3 is deleterious., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2021
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135. Immune regulations by 14-3-3: A misty terrain.
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Chakravarti R
- Subjects
- 14-3-3 Proteins chemistry, Adaptive Immunity, Animals, Antigens immunology, Cytokines metabolism, Humans, Immunity, Innate, Signal Transduction, Structure-Activity Relationship, 14-3-3 Proteins physiology, Immunomodulation
- Abstract
The 14-3-3 proteins are known for their functions related to the cell cycle and play a prominent role in cancer-related diseases. Recent studies show that 14-3-3 proteins are also regulators of immune responses and are involved in the pathogenesis of autoimmune and infectious diseases. This focused review highlights the significant and recent studies on how 14-3-3 proteins influence innate and adaptive immune responses; specifically, their roles as immunogens and cytokine signaling regulators are discussed. These revelations have added numerous questions to the pre-existing list of challenges, including understanding the 14-3-3 proteins' mechanism of immunogenicity to dissecting the isoform-specific immune regulations., (Copyright © 2021 Elsevier GmbH. All rights reserved.)
- Published
- 2021
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136. 14-3-3ζ: A suppressor of inflammatory arthritis.
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Kim J, Chun K, McGowan J, Zhang Y, Czernik PJ, Mell B, Joe B, Chattopadhyay S, Holoshitz J, and Chakravarti R
- Subjects
- 14-3-3 Proteins genetics, 14-3-3 Proteins immunology, Animals, Antibodies, Arthritis genetics, Arthritis metabolism, Bone Density, Bone Diseases metabolism, Bone Diseases prevention & control, Collagen metabolism, Collagen toxicity, Female, Freund's Adjuvant pharmacology, Gene Deletion, Gene Expression Regulation drug effects, Gene Expression Regulation immunology, Immunization, Passive, Male, Mesenchymal Stem Cells drug effects, RNA, Messenger genetics, RNA, Messenger metabolism, Rats, Terpenes toxicity, 14-3-3 Proteins metabolism, 14-3-3 Proteins pharmacology, Arthritis chemically induced, Inflammation drug therapy
- Abstract
Inflammatory arthritis (IA) is a common disease that affects millions of individuals worldwide. Proinflammatory events during IA pathogenesis are well studied; however, loss of protective immunity remains underexplored. Earlier, we reported that 14-3-3zeta (ζ) has a role in T-cell polarization and interleukin (IL)-17A signal transduction. Here, we demonstrate that 14-3-3ζ knockout (KO) rats develop early-onset severe arthritis in two independent models of IA, pristane-induced arthritis and collagen-induced arthritis. Arthritic 14-3-3ζ KO animals showed an increase in bone loss and immune cell infiltration in synovial joints. Induction of arthritis coincided with the loss of anti-14-3-3ζ antibodies; however, rescue experiments to supplement the 14-3-3ζ antibody by passive immunization did not suppress arthritis. Instead, 14-3-3ζ immunization during the presymptomatic phase resulted in significant suppression of arthritis in both wild-type and 14-3-3ζ KO animals. Mechanistically, 14-3-3ζ KO rats exhibited elevated inflammatory gene signatures at the messenger RNA and protein levels, particularly for IL-1β. Furthermore, the immunization with recombinant 14-3-3ζ protein suppressed IL-1β levels, significantly increased anti-14-3-3ζ antibody levels and collagen production, and preserved bone quality. The 14-3-3ζ protein increased collagen expression in primary rat mesenchymal cells. Together, our findings indicate that 14-3-3ζ causes immune suppression and extracellular remodeling, which lead to a previously unrecognized IA-suppressive function., Competing Interests: Competing interest statement: R.C. and B.J. hold a US patent related to the study. J.H. is an Inventor of Regents of the University of Michigan–owned technologies that are licensed to Zydus-Cadila, to whom he is an unpaid consultant.
- Published
- 2021
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137. Application of CRISPR/Cas System in the Metabolic Engineering of Small Molecules.
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Singh R, Chandel S, Ghosh A, Dey D, Chakravarti R, Roy S, Ravichandiran V, and Ghosh D
- Subjects
- Bacteria genetics, Genome, Microbial genetics, Yeasts genetics, CRISPR-Cas Systems genetics, Gene Editing methods, Metabolic Engineering methods, Small Molecule Libraries metabolism
- Abstract
Clustered regularly interspaced short palindromic repeats (CRISPR) and their associated Cas protein technology area is rapidly growing technique for genome editing and modulation of transcription of several microbes. Successful engineering in microbes requires an emphasis on the aspect of efficiency and targeted aiming, which can be employed using CRISPR/Cas system. Hence, this type of system is used to modify the genome of several microbes such as yeast and bacteria. In recent years, CRISPR/Cas systems have been chosen for metabolic engineering in microbes due to their specificity, orthogonality, and efficacy. Therefore, we need to review the scheme which was acquired for the execution of the CRISPR/Cas system for the modification and metabolic engineering in yeast and bacteria. In this review, we highlighted the application of the CRISPR/Cas system which has been used for the production of small molecules in the microbial system that is chemically and biologically important.
- Published
- 2021
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138. A review on potential of natural products in the management of COVID-19.
- Author
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Chakravarti R, Singh R, Ghosh A, Dey D, Sharma P, Velayutham R, Roy S, and Ghosh D
- Abstract
At the end of 2019, a life threatening viral infection (COVID-19) caused by a novel coronavirus, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) was reported. This virus has spread worldwide in a short duration and forced the world to face unprecedented life and economic loss. To date, there are no known specific drugs to combat this virus and the process for new drug development is lengthy. Most promising candidates, which emerged as potential leads, were abandoned in the later phases of clinical trials. Repurposing of already approved drugs for other therapeutic applications can be done only after extensive testing for safety and efficacy. With no definite therapeutics in the horizon, natural products are in extensive use arbitrarily as anti-viral agents and immune boosters. For ages it has been known that most natural products possess potent anti-viral activity and it is no different for SARS-CoV-2. It has been shown that natural products display inhibitory effects on MERS-CoV and SARS-CoV infections. In silico studies have shown that various natural products have strong binding affinity for and inhibitory action on the non-structural proteins of the virus, namely PL
PRO , MPRO , and RdRp, and structural proteins such as spike (S) protein. Since the virus utilizes the transmembrane ACE2 receptor of the host cell, it also proves to be a valid target for drug development. In this review promising targets for drug development against SARS-CoV-2 and anti-viral activities of some of the known natural products are discussed., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)- Published
- 2021
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139. Transcriptional and Non-Transcriptional Activation, Posttranslational Modifications, and Antiviral Functions of Interferon Regulatory Factor 3 and Viral Antagonism by the SARS-Coronavirus.
- Author
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Glanz A, Chakravarty S, Varghese M, Kottapalli A, Fan S, Chakravarti R, and Chattopadhyay S
- Subjects
- Animals, COVID-19 virology, Humans, Immunity, Innate, Interferon Regulatory Factor-3 genetics, Protein Processing, Post-Translational, SARS-CoV-2 genetics, COVID-19 genetics, COVID-19 immunology, Interferon Regulatory Factor-3 immunology, SARS-CoV-2 physiology
- Abstract
The immune system defends against invading pathogens through the rapid activation of innate immune signaling pathways. Interferon regulatory factor 3 (IRF3) is a key transcription factor activated in response to virus infection and is largely responsible for establishing an antiviral state in the infected host. Studies in Irf3
-/- mice have demonstrated the absence of IRF3 imparts a high degree of susceptibility to a wide range of viral infections. Virus infection causes the activation of IRF3 to transcribe type-I interferon (e.g., IFNβ), which is responsible for inducing the interferon-stimulated genes (ISGs), which act at specific stages to limit virus replication. In addition to its transcriptional function, IRF3 is also activated to trigger apoptosis of virus-infected cells, as a mechanism to restrict virus spread within the host, in a pathway called RIG-I-like receptor-induced IRF3 mediated pathway of apoptosis (RIPA). These dual functions of IRF3 work in concert to mediate protective immunity against virus infection. These two pathways are activated differentially by the posttranslational modifications (PTMs) of IRF3. Moreover, PTMs regulate not only IRF3 activation and function, but also protein stability. Consequently, many viruses utilize viral proteins or hijack cellular enzymes to inhibit IRF3 functions. This review will describe the PTMs that regulate IRF3's RIPA and transcriptional activities and use coronavirus as a model virus capable of antagonizing IRF3-mediated innate immune responses. A thorough understanding of the cellular control of IRF3 and the mechanisms that viruses use to subvert this system is critical for developing novel therapies for virus-induced pathologies.- Published
- 2021
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140. SARS-CoV-2, ACE2 expression, and systemic organ invasion.
- Author
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Ashraf UM, Abokor AA, Edwards JM, Waigi EW, Royfman RS, Hasan SA, Smedlund KB, Hardy AMG, Chakravarti R, and Koch LG
- Subjects
- COVID-19 epidemiology, COVID-19 virology, Host-Pathogen Interactions, Humans, Pandemics, Protein Binding, SARS-CoV-2 physiology, Virus Internalization, Angiotensin-Converting Enzyme 2 metabolism, COVID-19 metabolism, Renin-Angiotensin System physiology, SARS-CoV-2 metabolism, Spike Glycoprotein, Coronavirus metabolism
- Abstract
A novel coronavirus disease, COVID-19, has created a global pandemic in 2020, posing an enormous challenge to healthcare systems and affected communities. COVID-19 is caused by severe acute respiratory syndrome (SARS)-coronavirus-2 (CoV-2) that manifests as bronchitis, pneumonia, or a severe respiratory illness. SARS-CoV-2 infects human cells via binding a "spike" protein on its surface to angiotensin-converting enzyme 2 (ACE2) within the host. ACE2 is crucial for maintaining tissue homeostasis and negatively regulates the renin-angiotensin-aldosterone system (RAAS) in humans. The RAAS is paramount for normal function in multiple organ systems including the lungs, heart, kidney, and vasculature. Given that SARS-CoV-2 internalizes via ACE2, the resultant disruption in ACE2 expression can lead to altered tissue function and exacerbate chronic diseases. The widespread distribution and expression of ACE2 across multiple organs is critical to our understanding of the varied clinical outcomes of COVID-19. This perspective review based on the current literature was prompted to show how disruption of ACE2 by SARS-CoV-2 can affect different organ systems.
- Published
- 2021
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141. 14-3-3ζ-TRAF5 axis governs interleukin-17A signaling.
- Author
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McGowan J, Peter C, Kim J, Popli S, Veerman B, Saul-McBeth J, Conti H, Pruett-Miller SM, Chattopadhyay S, and Chakravarti R
- Subjects
- 14-3-3 Proteins genetics, Animals, Autoimmune Diseases pathology, Chemokines genetics, Cytokines genetics, Gene Expression Regulation genetics, Humans, Mice, Rats, Signal Transduction genetics, TNF Receptor-Associated Factor 5 genetics, TNF Receptor-Associated Factor 6 genetics, Autoimmune Diseases genetics, Chemokine CXCL1 genetics, Interleukin-17 genetics, Interleukin-6 genetics
- Abstract
IL-17A is a therapeutic target in many autoimmune diseases. Most nonhematopoietic cells express IL-17A receptors and respond to extracellular IL-17A by inducing proinflammatory cytokines. The IL-17A signal transduction triggers two broad, TRAF6- and TRAF5-dependent, intracellular signaling pathways to produce representative cytokines (IL-6) and chemokines (CXCL-1), respectively. Our limited understanding of the cross-talk between these two branches has generated a crucial gap of knowledge, leading to therapeutics indiscriminately blocking IL-17A and global inhibition of its target genes. In previous work, we discovered an elevated expression of 14-3-3 proteins in inflammatory aortic disease, a rare human autoimmune disorder with increased levels of IL-17A. Here we report that 14-3-3ζ is essential for IL-17 signaling by differentially regulating the signal-induced IL-6 and CXCL-1. Using genetically manipulated human and mouse cells, and ex vivo and in vivo rat models, we uncovered a function of 14-3-3ζ. As a part of the molecular mechanism, we show that 14-3-3ζ interacts with several TRAF proteins; in particular, its interaction with TRAF5 and TRAF6 is increased in the presence of IL-17A. In contrast to TRAF6, we found TRAF5 to be an endogenous suppressor of IL-17A-induced IL-6 production, an effect countered by 14-3-3ζ. Furthermore, we observed that 14-3-3ζ interaction with TRAF proteins is required for the IL-17A-induced IL-6 levels. Together, our results show that 14-3-3ζ is an essential component of IL-17A signaling and IL-6 production, an effect that is suppressed by TRAF5. To the best of our knowledge, this report of the 14-3-3ζ-TRAF5 axis, which differentially regulates IL-17A-induced IL-6 and CXCL-1 production, is unique., Competing Interests: The authors declare no competing interest.
- Published
- 2020
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142. The interferon-inducible protein TDRD7 inhibits AMP-activated protein kinase and thereby restricts autophagy-independent virus replication.
- Author
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Subramanian G, Popli S, Chakravarty S, Taylor RT, Chakravarti R, and Chattopadhyay S
- Subjects
- AMP-Activated Protein Kinases genetics, Animals, Chlorocebus aethiops, HeLa Cells, Humans, Mice, Ribonucleoproteins genetics, Vero Cells, AMP-Activated Protein Kinases metabolism, Autophagy, Herpesvirus 1, Human physiology, Ribonucleoproteins metabolism, Virus Replication
- Abstract
The interferon system is the first line of defense against virus infection. Recently, using a high-throughput genetic screen of a human interferon-stimulated gene short-hairpin RNA library, we identified a viral restriction factor, TDRD7 (Tudor domain-containing 7). TDRD7 inhibits the paramyxo-/pneumoviruses ( e.g. Sendai virus and respiratory syncytial virus) by interfering with the virus-induced cellular autophagy pathway, which these viruses use for their replication. Here, we report that TDRD7 is a viral restriction factor against herpes simplex virus (HSV-1). Using knockdown, knockout, and ectopic expression systems, we demonstrate the anti-HSV-1 activity of TDRD7 in multiple human and mouse cell types. TDRD7 inhibited the virus-activated AMP-activated protein kinase (AMPK), which was essential for HSV-1 replication. Genetic ablation or chemical inhibition of AMPK activity suppressed HSV-1 replication in multiple human and mouse cells. Mechanistically, HSV-1 replication after viral entry depended on AMPK but not on its function in autophagy. The antiviral activity of TDRD7 depended on its ability to inhibit virus-activated AMPK. In summary, our results indicate that the newly identified viral restriction factor TDRD7 inhibits AMPK and thereby blocks HSV-1 replication independently of the autophagy pathway. These findings suggest that AMPK inhibition represents a potential strategy to manage HSV-1 infections., (© 2020 Subramanian et al.)
- Published
- 2020
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143. High Throughput Screening of FDA-Approved Drug Library Reveals the Compounds that Promote IRF3-Mediated Pro-Apoptotic Pathway Inhibit Virus Replication.
- Author
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Glanz A, Chawla K, Fabry S, Subramanian G, Garcia J, Jay B, Ciricillo J, Chakravarti R, Taylor RT, and Chattopadhyay S
- Subjects
- Doxorubicin pharmacology, Drug Evaluation, Preclinical, Host-Pathogen Interactions drug effects, Host-Pathogen Interactions immunology, Humans, Immunity, Innate drug effects, MAP Kinase Signaling System drug effects, Models, Biological, Small Molecule Libraries, Vesicular stomatitis Indiana virus drug effects, Antiviral Agents pharmacology, Apoptosis drug effects, High-Throughput Screening Assays methods, Interferon Regulatory Factor-3 metabolism, Signal Transduction drug effects, Virus Replication drug effects
- Abstract
Interferon (IFN) regulatory factor 3 (IRF3) is the key transcription factor for the induction of IFN and antiviral genes. The absence of antiviral genes in IRF3 deficiency leads to susceptibility to a wide range of viral infections. Previously, we uncovered a function for nontranscriptional IRF3 (nt-IRF3), RLR (RIG-I-like receptor)-induced IRF3-mediated pathway of apoptosis (RIPA), which triggers apoptotic killing of virus-infected cells. Using knock-in mice expressing a transcriptionally inactive, but RIPA-active, IRF3 mutant, we demonstrated the relative contribution of RIPA to host antiviral defense. Given that RIPA is a cellular antiviral pathway, we hypothesized that small molecules that promote RIPA in virus-infected cells would act as antiviral agents. To test this, we conducted a high throughput screen of a library of FDA-approved drugs to identify novel RIPA activators. Our screen identified doxorubicin as a potent RIPA-activating agent. In support of our hypothesis, doxorubicin inhibited the replication of vesicular stomatitis virus, a model rhabdovirus, and its antiviral activity depended on its ability to activate IRF3 in RIPA. Surprisingly, doxorubicin inhibited the transcriptional activity of IRF3. The antiviral activity of doxorubicin was expanded to flavivirus and herpesvirus that also activate IRF3. Mechanistically, doxorubicin promoted RIPA by activating the extracellular signal-regulated kinase (ERK) signaling pathway. Finally, we validated these results using another RIPA-activating compound, pyrvinium pamoate, which showed a similar antiviral effect without affecting the transcriptional activity of IRF3. Therefore, we demonstrate that the RIPA branch of IRF3 can be targeted therapeutically to prevent virus infection.
- Published
- 2020
- Full Text
- View/download PDF
144. Mechanism and biomarkers in aortitis--a review.
- Author
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Benhuri B, ELJack A, Kahaleh B, and Chakravarti R
- Subjects
- Aged, Aged, 80 and over, Aortitis therapy, Autoantibodies blood, Biomarkers blood, Blood Sedimentation, C-Reactive Protein analysis, Cytokines blood, Female, Humans, Immunosuppression Therapy methods, Inflammation blood, Male, Middle Aged, Aortitis blood, Aortitis diagnosis, Autoimmune Diseases blood, Autoimmune Diseases diagnosis
- Abstract
Aortitis can be the manifestation of an underlying infectious or noninfectious disease process. An autoimmune cause is suggested in a large proportion of noninfectious causes. Similar to other autoimmune diseases, the pathophysiology of aortitis has been investigated in detail, but the etiology remains unknown. Most cases of aortitis often go undetected for a long time and are often identified at late stages of the disease. Recent advances in imaging techniques have significantly improved the diagnosis of aortitis. However, significant challenges associated with the imaging techniques limit their use. Several routine inflammation-based markers, such as erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and inflammatory cytokines, are nonspecific and, therefore, have limited use in the diagnosis of aortitis. The search for more specific serum biomarkers, which can facilitate detection and progression is under progress. Several autoantibodies have been identified, but assigning their role in the pathogenesis as well as their specificity remains a challenge. The current review addresses some of these issues in detail. KEY MESSAGES: • Noninfectious aortitis is an autoimmune disease. • Several biomarkers, including cytokines and autoantibodies, are increased in aortitis. • Imaging techniques, commonly used to detect aortitis, are associated with the high cost and technical challenges. • There is a need to develop low-cost biomarker-based detection tools. • The knowledge of biomarkers in aortitis detection is discussed.
- Published
- 2020
- Full Text
- View/download PDF
145. 14-3-3ζ-A Novel Immunogen Promotes Inflammatory Cytokine Production.
- Author
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McGowan J, Peter C, Chattopadhyay S, and Chakravarti R
- Subjects
- Autoimmune Diseases pathology, Humans, Th1 Cells pathology, Th17 Cells pathology, 14-3-3 Proteins immunology, Autoimmune Diseases immunology, HLA-DRB1 Chains immunology, Interferon-gamma immunology, Th1 Cells immunology, Th17 Cells immunology
- Abstract
The presence of autoantibodies against 14-3-3ζ in human autoimmune diseases indicates its antigenic function. However, neither the cause nor the consequence of this newly-identified antigenic function of 14-3-3ζ protein is known. To address this, we investigated the immunological functions of 14-3-3ζ by studying ex vivo effects on human peripheral blood mononuclear cells (PBMC) proliferation, polarization, and cytokine production. Exogenous 14-3-3ζ promoted PBMC proliferation and T cell polarization toward Th1 and Th17 populations. Significant increases in IFN-γ and IL-17 levels were observed in the presence of 14-3-3ζ. A specific increase in Th1 cells and IFN-γ production provided strong evidence for MHC class II presentation of 14-3-3ζ antigen. Particularly HLA-DRB1
* 0401 allele strongly promoted 14-3-3ζ-induced IFN-γ producing cells. In contrast, prednisolone treatment suppressed both 14-3-3ζ-induced T cell polarization and cytokine production. Overall, we show that MHC presentation and the adaptor functions of 14-3-3ζ participate in promoting IFN-γ and IL-17 production, two of the cytokines commonly associated with autoimmune diseases. To the best of our knowledge, this is the first report describing the ex vivo antigenic function of 14-3-3ζ with human PBMC, thereby providing the basis of its immunological role in human diseases.- Published
- 2019
- Full Text
- View/download PDF
146. Ifi204/p204, a new piece in the sepsis puzzle.
- Author
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Subramanian G, Chakravarti R, and Chattopadhyay S
- Abstract
Competing Interests: Conflicts of Interest: The authors have no conflicts of interest to declare.
- Published
- 2018
- Full Text
- View/download PDF
147. Glyceraldehyde-3-phosphate dehydrogenase is a chaperone that allocates labile heme in cells.
- Author
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Sweeny EA, Singh AB, Chakravarti R, Martinez-Guzman O, Saini A, Haque MM, Garee G, Dans PD, Hannibal L, Reddi AR, and Stuehr DJ
- Subjects
- Amino Acid Sequence, Animals, Binding Sites, Crystallography, X-Ray, Glyceraldehyde-3-Phosphate Dehydrogenases chemistry, Glyceraldehyde-3-Phosphate Dehydrogenases genetics, Heme chemistry, Humans, Mice, Molecular Chaperones chemistry, Molecular Chaperones genetics, Molecular Sequence Data, Nitric Oxide Synthase Type II genetics, Nitric Oxide Synthase Type II metabolism, Protein Binding, Sequence Alignment, Glyceraldehyde-3-Phosphate Dehydrogenases metabolism, Heme metabolism, Molecular Chaperones metabolism
- Abstract
Cellular heme is thought to be distributed between a pool of sequestered heme that is tightly bound within hemeproteins and a labile heme pool required for signaling and transfer into proteins. A heme chaperone that can hold and allocate labile heme within cells has long been proposed but never been identified. Here, we show that the glycolytic protein glyceraldehyde-3-phosphate dehydrogenase (GAPDH) fulfills this role by acting as an essential repository and allocator of bioavailable heme to downstream protein targets. We identified a conserved histidine in GAPDH that is needed for its robust heme binding both in vitro and in mammalian cells. Substitution of this histidine, and the consequent decreases in GAPDH heme binding, antagonized heme delivery to both cytosolic and nuclear hemeprotein targets, including inducible nitric-oxide synthase (iNOS) in murine macrophages and the nuclear transcription factor Hap1 in yeast, even though this GAPDH variant caused cellular levels of labile heme to rise dramatically. We conclude that by virtue of its heme-binding property, GAPDH binds and chaperones labile heme to create a heme pool that is bioavailable to downstream proteins. Our finding solves a fundamental question in cell biology and provides a new foundation for exploring heme homeostasis in health and disease., (© 2018 Sweeny et al.)
- Published
- 2018
- Full Text
- View/download PDF
148. Nitric oxide alters hyaluronan deposition by airway smooth muscle cells.
- Author
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Majors AK, Chakravarti R, Ruple LM, Leahy R, Stuehr DJ, Lauer M, Erzurum SC, Janocha A, and Aronica MA
- Subjects
- Animals, Cell Adhesion, Leukocytes cytology, Leukocytes metabolism, Mice, Myocytes, Smooth Muscle cytology, RAW 264.7 Cells, Hyaluronic Acid metabolism, Myocytes, Smooth Muscle metabolism, Nitric Oxide metabolism, Respiratory System cytology
- Abstract
Asthma is a chronic inflammatory disease that is known to cause changes in the extracellular matrix, including changes in hyaluronan (HA) deposition. However, little is known about the factors that modulate its deposition or the potential consequences. Asthmatics with high levels of exhaled nitric oxide (NO) are characterized by greater airway reactivity and greater evidence of airway inflammation. Based on these data and our previous work we hypothesized that excessive NO promotes the pathologic production of HA by airway smooth muscle cells (SMCs). Exposure of cultured SMCs to various NO donors results in the accumulation of HA in the form of unique, cable-like structures. HA accumulates rapidly after exposure to NO and can be seen as early as one hour after NO treatment. The cable-like HA in NO-treated SMC cultures supports the binding of leukocytes. In addition, NO produced by murine macrophages (RAW cells) and airway epithelial cells also induces SMCs to produce HA cables when grown in co-culture. The modulation of HA by NO appears to be independent of soluble guanylate cyclase. Taken together, NO-induced production of leukocyte-binding HA by SMCs provides a new potential mechanism for the non-resolving airway inflammation in asthma and suggests a key role of non-immune cells in driving the chronic inflammation of the submucosa. Modulation of NO, HA and the consequent immune cell interactions may serve as potential therapeutic targets in asthma., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2018
- Full Text
- View/download PDF
149. A new mechanism of interferon's antiviral action: Induction of autophagy, essential for paramyxovirus replication, is inhibited by the interferon stimulated gene, TDRD7.
- Author
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Subramanian G, Kuzmanovic T, Zhang Y, Peter CB, Veleeparambil M, Chakravarti R, Sen GC, and Chattopadhyay S
- Subjects
- Animals, Cells, Cultured, Gene Expression Regulation drug effects, HEK293 Cells, HeLa Cells, Humans, Immunity, Innate drug effects, Immunity, Innate genetics, Mice, Mice, Inbred C57BL, Ribonucleoproteins genetics, Signal Transduction drug effects, Signal Transduction genetics, Virus Replication genetics, Antiviral Agents pharmacology, Autophagy genetics, Autophagy immunology, Interferons pharmacology, Paramyxovirinae physiology, Ribonucleoproteins physiology, Virus Replication drug effects
- Abstract
The interferon (IFN) system represents the first line of defense against a wide range of viruses. Virus infection rapidly triggers the transcriptional induction of IFN-β and IFN Stimulated Genes (ISGs), whose protein products act as viral restriction factors by interfering with specific stages of virus life cycle, such as entry, transcription, translation, genome replication, assembly and egress. Here, we report a new mode of action of an ISG, IFN-induced TDRD7 (tudor domain containing 7) inhibited paramyxovirus replication by inhibiting autophagy. TDRD7 was identified as an antiviral gene by a high throughput screen of an ISG shRNA library for blocking IFN's protective effect against Sendai virus (SeV) replication. The antiviral activity of TDRD7 against SeV, human parainfluenza virus 3 and respiratory syncytial virus was confirmed by its genetic ablation or ectopic expression in several types of mouse and human cells. TDRD7's antiviral action was mediated by its ability to inhibit autophagy, a cellular catabolic process which was robustly induced by SeV infection and required for its replication. Mechanistic investigation revealed that TDRD7 interfered with the activation of AMP-dependent kinase (AMPK), an enzyme required for initiating autophagy. AMPK activity was required for efficient replication of several paramyxoviruses, as demonstrated by its genetic ablation or inhibition of its activity by TDRD7 or chemical inhibitors. Therefore, our study has identified a new antiviral ISG with a new mode of action.
- Published
- 2018
- Full Text
- View/download PDF
150. Bioinformatic analysis reveals new determinants of antigenic 14-3-3 proteins and a novel antifungal strategy.
- Author
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McGowan JE, Kratch J, Chattopadhyay S, Joe B, Conti HR, and Chakravarti R
- Subjects
- 14-3-3 Proteins chemistry, 14-3-3 Proteins immunology, 14-3-3 Proteins pharmacology, Amino Acid Sequence, Humans, Sequence Homology, Amino Acid, 14-3-3 Proteins metabolism, Antifungal Agents pharmacology, Candida albicans drug effects, Computational Biology, Saccharomyces cerevisiae drug effects
- Abstract
The ubiquitously expressed 14-3-3 family of proteins is evolutionarily conserved from yeast to mammals. Their involvement in humoral and cellular immune responses is emerging through studies in drosophila and humans. In humans, a select group of 14-3-3 isoforms are antigenic; however the determinants of their antigenicity are not known. Here, we show that although mammalian 14-3-3 proteins are mostly conserved, subtle differences between their isoforms may give rise to their antigenicity. We observed syntenic relations among all the isoforms of 14-3-3 for mammals, but not with that of birds or amphibians. However, the parasitic 14-3-3 isoforms, which have known antigenic properties, show unique sequence, structure and evolution compared to the human 14-3-3. Moreover we report, for the first time the existence of a bacterial 14-3-3 protein. Contrary to the parasitic isoforms, both bacterial and yeast 14-3-3 exhibited significant homology with mammalian 14-3-3 in protein sequence as well as structure. Furthermore, a human 14-3-3 inhibitor caused significant killing of Candida albicans, which could be due to the inhibition of the structurally similar yeast homologue of 14-3-3, BMH, which is essential for its life cycle. Overall, our bioinformatic analysis combined with the demonstration of a novel antifungal role of a peptide inhibitor of human 14-3-3 indicates that the sequences and structural similarities between the mammalian, bacterial and fungal proteins are likely determinants of the antigenic nature of these proteins. Further, we propose that molecular mimicry triggered by microbial infections with either yeast or bacteria may contribute to the antigenic role of human 14-3-3.
- Published
- 2017
- Full Text
- View/download PDF
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