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Singh G, Shankar G, Panda SR, Kumar S, Rai S, Verma H, Kumar P, Nayak PK, Naidu VGM, Srikrishna S, Kumar S, Modi G. Design, Synthesis, and Biological Evaluation of Ferulic Acid Template-Based Novel Multifunctional Ligands Targeting NLRP3 Inflammasome for the Management of Alzheimer's Disease. ACS Chem Neurosci 2024; 15:1388-1414. [PMID: 38525886 DOI: 10.1021/acschemneuro.3c00679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2024] Open
Abstract
Alzheimer's disease (AD) is the most common cause of dementia, which arises due to low levels of acetyl and butyrylcholines, an increase in oxidative stress, inflammation, metal dyshomeostasis, Aβ and tau aggregations. The currently available drugs for AD treatment can provide only symptomatic relief without interfering with pathological hallmarks of the disease. In our ongoing efforts to develop naturally inspired novel multifunctional molecules for AD, systematic SAR studies on EJMC-4e were caried out to improve its multifunctional properties. The rigorous medicinal efforts led to the development of 12o, which displayed a 15-fold enhancement in antioxidant properties and a 2-fold increase in the activity against AChE and BChE over EJMC-4e. Molecular docking and dynamics studies revealed the binding sites and stability of the complex of 12o with AChE and BChE. The PAMPA-BBB assay clearly demonstrated that 12o can easily cross the blood-brain barrier. Interestingly, 12o also expresses promising metal chelation activity, while EJMC-4e was found to be devoid of this property. Further, 12o inhibited metal-induced or self Aβ1-42 aggregation. Observing the neuroprotection ability of 12o against H2O2-induced oxidative stress in the PC-12 cell line is noteworthy. Furthermore, 12o also inhibited NLRP3 inflammasome activation and attenuated mitochondrial-induced ROS and MMP damage caused by LPS and ATP in HMC-3 cells. In addition, 12o is able to effectively reduce mitochondrial and cellular oxidative stress in the AD Drosophila model. Finally, 12o could reverse memory impairment in the scopolamine-induced AD mice model, as evident through in vivo and ex vivo studies. These findings suggest that this compound may act as a promising candidate for further improvement in the management of AD.
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Affiliation(s)
- Gourav Singh
- Department of Pharmaceutical Engineering and Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005, India
| | - Gauri Shankar
- Department of Pharmaceutical Engineering and Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005, India
| | - Samir Ranjan Panda
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Guwahati, Assam 781032, India
| | - Sunil Kumar
- Department of Pharmaceutical Engineering and Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005, India
| | - Sanskriti Rai
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi 110029, India
| | - Himanshu Verma
- Department of Pharmaceutical Engineering and Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005, India
| | - Prabhat Kumar
- Department of Biochemistry, Institute of Sciences, Banaras Hindu University, Varanasi 201005, India
| | - Prasanta Kumar Nayak
- Department of Pharmaceutical Engineering and Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005, India
| | - V G M Naidu
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Guwahati, Assam 781032, India
| | - Saripella Srikrishna
- Department of Biochemistry, Institute of Sciences, Banaras Hindu University, Varanasi 201005, India
| | - Saroj Kumar
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi 110029, India
| | - Gyan Modi
- Department of Pharmaceutical Engineering and Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005, India
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Singh G, Kesharwani P, Kumar Singh G, Kumar S, Putta A, Modi G. Ferroptosis and its modulators: A raising target for cancer and Alzheimer's disease. Bioorg Med Chem 2024; 98:117564. [PMID: 38171251 DOI: 10.1016/j.bmc.2023.117564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2023] [Revised: 12/01/2023] [Accepted: 12/18/2023] [Indexed: 01/05/2024]
Abstract
The process of ferroptosis, a recently identified form of regulated cell death (RCD) is associated with the overloading of iron species and lipid-derived ROS accumulation. Ferroptosis is induced by various mechanisms such as inhibiting system Xc, glutathione depletion, targeting excess iron, and directly inhibiting GPX4 enzyme. Also, ferroptosis inhibition is achieved by blocking excessive lipid peroxidation by targeting different pathways. These mechanisms are often related to the pathophysiology and pathogenesis of diseases like cancer and Alzheimer's. Fundamentally distinct from other forms of cell death, such as necrosis and apoptosis, ferroptosis differs in terms of biochemistry, functions, and morphology. The mechanism by which ferroptosis acts as a regulatory factor in many diseases remains elusive. Studying the activation and inhibition of ferroptosis as a means to mitigate the progression of various diseases is a highly intriguing and actively researched topic. It has emerged as a focal point in etiological research and treatment strategies. This review systematically summarizes the different mechanisms involved in the inhibition and induction of ferroptosis. We have extensively explored different agents that can induce or inhibit ferroptosis. This review offers current perspectives on recent developments in ferroptosis research, highlighting the disease's etiology and presenting references to enhance its understanding. It also explores new targets for the treatment of cancer and Alzheimer's disease.
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Affiliation(s)
- Gourav Singh
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005, India
| | - Prashant Kesharwani
- Department of Pharmaceutics, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi, 110062, India
| | - Gireesh Kumar Singh
- Department of Pharmacy, School of Health Science, Central University of South Bihar Gaya, 824236, India
| | - Saroj Kumar
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi 110029, India
| | - Anjaneyulu Putta
- Department of Chemistry, University of South Dakota, Churchill Haines, Vermillion SD-57069, United States
| | - Gyan Modi
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005, India.
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Narayanan AC, Venkatesh R, Singh S, Singh G, Modi G, Singh S, Kandasamy J. Synthesis of phenylethanoid glycosides from acrylic esters of glucose and aryldiazonium salts via palladium-catalyzed cross-coupling reactions and evaluation of their anti-Alzheimer activity. Carbohydr Res 2023; 532:108920. [PMID: 37586143 DOI: 10.1016/j.carres.2023.108920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Revised: 07/13/2023] [Accepted: 08/02/2023] [Indexed: 08/18/2023]
Abstract
Cinnamic acid-containing sugar compounds such as phenylethanoid glycosides are widely present in nature and display various biological activities. In this work, the synthesis of trans-cinnamic acid containing phenylethanoid glycosides was achieved via palladium-catalyzed cross-coupling reactions between glycosyl acrylic esters and aryldiazonium salts. A wide range of functionalized aryldiazonium salts were successfully coupled with 6-O- and 4-O-acrylic esters of glucose under optimized conditions. The reactions proceeded at room temperature in the absence of additives and base. The desired products were obtained in good to excellent yields. Selected compounds from the library were screened for anti-Alzheimer activity, while compound 16 displayed significant inhibitory activities against butyrylcholinesterase (BChE) and acetylcholinesterase (AChE) enzymes.
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Affiliation(s)
- Aswathi C Narayanan
- Department of Chemistry, Indian Institute of Technology (BHU), Varanasi, Uttar Pradesh, 221005, India
| | - Rapelly Venkatesh
- Department of Chemistry, Indian Institute of Technology (BHU), Varanasi, Uttar Pradesh, 221005, India
| | - Shweta Singh
- Department of Chemistry, Indian Institute of Technology (BHU), Varanasi, Uttar Pradesh, 221005, India
| | - Gourav Singh
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Gyan Modi
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Sundaram Singh
- Department of Chemistry, Indian Institute of Technology (BHU), Varanasi, Uttar Pradesh, 221005, India
| | - Jeyakumar Kandasamy
- Department of Chemistry, Indian Institute of Technology (BHU), Varanasi, Uttar Pradesh, 221005, India; Department of Chemistry, Pondicherry University, Pondicherry, 605014, India.
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Singh G, Thomas J, Wadhawa S, Kashyap A, Rahaman SA, Borkotoky S, Datta A, Singh GK, Mishra I, Rai G, Satija J, Dubey VK, Modi G. Repurposing the in-house generated Alzheimer's disease targeting molecules through computational and preliminary in-vitro studies for the management of SARS-coronavirus-2. Mol Divers 2023:10.1007/s11030-023-10717-4. [PMID: 37749454 DOI: 10.1007/s11030-023-10717-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 08/14/2023] [Indexed: 09/27/2023]
Abstract
Covid-19 was declared a world pandemic. Recent studies demonstrated that Covid-19 impairs CNS activity by crossing the blood-brain barrier and ensuing cognitive impairment. In this study, we have utilized Covid-19 main protease (Mpro) as a biological target to repurpose our previously reported multifunctional compounds targeting Alzheimer's disease. Molecular docking, spatial orientation, molecular dynamics simulation, MM-GBSA energy calculation, and DFT studies were carried out with these molecules. Among all the compounds, F27, F44, and F56 exhibited higher binding energy (- 8.03, - 8.65, and - 8.68 kcal/mol, respectively) over the co-crystal ligand O6K (- 7.00 kcal/mol). In MD simulation, compounds F27, F44, and F56 could make a stable complex with Mpro target throughout the simulation. The compounds were synthesized following reported methods and subjected for cytotoxicity, and assessment of their capability to cross the blood-brain barrier in PAMPA assay, and antioxidant property evaluation through DPPH assay. The compounds F27, F44, and F56 exhibited cytocompatibility with the SiHA cell line and also displayed significant antioxidant properties with IC50 = 45.80 ± 0.27 μM, 44.42 ± 0.30 μM, and 42.74 ± 0.23 μM respectively. In the PAMPA assays, the permeability coefficient (Pe) value of F27, F44, and F56 lies in the acceptable range (Pe > 4). The results of the computational and preliminary in-vitro studies strongly corroborate the potential of F27, F44, and F56 as a lead for further optimization in treating the CNS complications associated with Covid-19.
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Affiliation(s)
- Gourav Singh
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Jobin Thomas
- Centre for Nanobiotechnology, Vellore Institute of Technology, Vellore, 632014, India
| | - Sahil Wadhawa
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Anurag Kashyap
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Syed Ajijur Rahaman
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Subhomoi Borkotoky
- School of Biochemical Engineering, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
- Department of Biotechnology, Faculty of Biosciences, Invertis University, Bareilly, 243123, India
| | - Agnisha Datta
- Department of Molecular and Human Genetics, Institute of Science, Banaras Hindu University, Varanasi, 221005, India
| | - Gireesh Kumar Singh
- Department of Pharmacy, School of Health Science, Central University of South Bihar, Gaya, Bihar, 824236, India
| | | | - Geeta Rai
- Department of Molecular and Human Genetics, Institute of Science, Banaras Hindu University, Varanasi, 221005, India
| | - Jitendra Satija
- Centre for Nanobiotechnology, Vellore Institute of Technology, Vellore, 632014, India
| | - Vikash Kumar Dubey
- School of Biochemical Engineering, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Gyan Modi
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India.
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Kumar J, Shankar G, Kumar S, Thomas J, Singh N, Srikrishna S, Satija J, Krishnamurthy S, Modi G, Mishra SK. Extraction, isolation, synthesis, and biological evaluation of novel piperic acid derivatives for the treatment of Alzheimer's disease. Mol Divers 2023:10.1007/s11030-023-10667-x. [PMID: 37351693 DOI: 10.1007/s11030-023-10667-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 05/31/2023] [Indexed: 06/24/2023]
Abstract
In this paper, we developed a series of piperic acid (PA) analogs with the aim of overcoming the limitations associated with the natural products for the management of Alzheimer's disease (AD). A comprehensive SAR study was performed to enhance cholinesterase inhibition of PA. The acetylcholinesterase inhibition and its kinetic data suggested 6j as the lead molecule (AChE IC50 = 2.13 ± 0.015 µM, BChE = 28.19 ± 0.20%), in comparison to PA (AChE = 7.14 ± 0.98%) which was further selected for various biological studies in AD models. 6j, exhibited interaction with the peripheral anionic site of AChE, BBB permeability (Pe = 7.98), and antioxidant property (% radical scavenging activity = 35.41 ± 1.09, 2.43 ± 1.65, for 6j and PA at 20 M[Formula: see text], respectively). The result from the metal chelation study suggests that 6j did not effectively chelate iron. The molecular modeling studies suggested that 6j could effectively interact with Ser293, Phe295, Arg296, and Tyr34 of AChE. In the cell-based cytotoxicity studies, 6j exhibited cytocompatibility at the different tested concentrations. The acute toxicity data on mice suggested that compound 6j had no renal and hepatotoxicity at 500 mg/kg. Moreover, 6j could effectively reverse scopolamine-induced amnesia by improving spatial and cognitive memory in mice. The above results strongly suggest that compound 6j may act as a novel multi-targeted lead for AD therapy.
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Affiliation(s)
- Jitendra Kumar
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Gauri Shankar
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Sunil Kumar
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Jobin Thomas
- Centre for Nanobiotechnology, Vellore Institute of Technology, Vellore, 632014, India
| | - Neha Singh
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Saripella Srikrishna
- Department of Biochemistry, Faculty of Science, Banaras Hindu University, Varanasi, 221 005, India
| | - Jitendra Satija
- Centre for Nanobiotechnology, Vellore Institute of Technology, Vellore, 632014, India
| | - Sairam Krishnamurthy
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Gyan Modi
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Sunil Kumar Mishra
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India.
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Arora V, Abourehab MA, Modi G, Kesharwani P. Dendrimers as prospective nanocarrier for targeted delivery against lung cancer. Eur Polym J 2022. [DOI: 10.1016/j.eurpolymj.2022.111635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Rai H, Gupta S, Kumar S, Yang J, Singh SK, Ran C, Modi G. Near-Infrared Fluorescent Probes as Imaging and Theranostic Modalities for Amyloid-Beta and Tau Aggregates in Alzheimer's Disease. J Med Chem 2022; 65:8550-8595. [PMID: 35759679 DOI: 10.1021/acs.jmedchem.1c01619] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A person suspected of having Alzheimer's disease (AD) is clinically diagnosed for the presence of principal biomarkers, especially misfolded amyloid-beta (Aβ) and tau proteins in the brain regions. Existing radiotracer diagnostic tools, such as PET imaging, are expensive and have limited availability for primary patient screening and pre-clinical animal studies. To change the status quo, small-molecular near-infrared (NIR) probes have been rapidly developed, which may serve as an inexpensive, handy imaging tool to comprehend the dynamics of pathogenic progression in AD and assess therapeutic efficacy in vivo. This Perspective summarizes the biochemistry of Aβ and tau proteins and then focuses on structurally diverse NIR probes with coverages of their spectroscopic properties, binding affinity toward Aβ and tau species, and theranostic effectiveness. With the summarized information and perspective discussions, we hope that this paper may serve as a guiding tool for designing novel in vivo imaging fluoroprobes with theranostic capabilities in the future.
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Affiliation(s)
- Himanshu Rai
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (BHU), Varanasi, U.P.-221005, India
| | - Sarika Gupta
- Molecular Science Laboratory, National Institute of Immunology, New Delhi-110067, India
| | - Saroj Kumar
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi-110029, India
| | - Jian Yang
- School of Medicine, Shanghai University, Shanghai 200444, China
| | - Sushil K Singh
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (BHU), Varanasi, U.P.-221005, India
| | - Chongzhao Ran
- Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, United States
| | - Gyan Modi
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (BHU), Varanasi, U.P.-221005, India
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Venkatesh R, Shankar G, Narayanan AC, Modi G, Sabiah S, Kandasamy J. Multicomponent Synthesis of S-Benzyl Dithiocarbamates from para-Quinone Methides and Their Biological Evaluation for the Treatment of Alzheimer's Disease. J Org Chem 2022; 87:6730-6741. [PMID: 35545917 DOI: 10.1021/acs.joc.2c00423] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Multicomponent synthesis of biologically relevant S-benzyl dithiocarbamates from para-quinone methides, amines, and carbon disulfide are described under catalyst and additive-free conditions. The reactions proceeded at room temperature in a short span of time with excellent yields. One of the synthesized compounds, 3e showed considerable acetylcholinesterase (AChE) inhibitory (51.70 + 5.63% at 20 μm) and antioxidant (63.52 ± 1.15 at 20 μm) activities.
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Affiliation(s)
- Rapelly Venkatesh
- Department of Chemistry, Indian Institute of Technology (BHU), Varanasi, Uttar Pradesh 221005, India
| | - Gauri Shankar
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005, India
| | - Aswathi C Narayanan
- Department of Chemistry, Indian Institute of Technology (BHU), Varanasi, Uttar Pradesh 221005, India
| | - Gyan Modi
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005, India
| | | | - Jeyakumar Kandasamy
- Department of Chemistry, Indian Institute of Technology (BHU), Varanasi, Uttar Pradesh 221005, India
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Singh YP, Kumar N, Priya K, Chauhan BS, Shankar G, Kumar S, Singh GK, Srikrishna S, Garg P, Singh G, Rai G, Modi G. Exploration of Neuroprotective Properties of a Naturally Inspired Multifunctional Molecule (F24) against Oxidative Stress and Amyloid β Induced Neurotoxicity in Alzheimer's Disease Models. ACS Chem Neurosci 2022; 13:27-42. [PMID: 34931800 DOI: 10.1021/acschemneuro.1c00443] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The pathological hallmarks of Alzheimer's disease (AD) are manifested as an increase in the level of oxidative stress and aggregation of the amyloid-β protein. In vitro, in vivo, and in silico experiments were designed and carried out with multifunctional cholinergic inhibitor, F24 (EJMC-7a) to explore its neuroprotective effects in AD models. The neuroprotection ability of F24 was tested in SH-SY5Y cells, a widely used neuronal cell line. The pretreatment and subsequent co-treatment of SH-SY5Y cells with different doses of F24 was effective in rescuing the cells from H2O2 induced neurotoxicity. F24 treated cells were found to be effective in the reduction of cellular reactive oxygen species, DNA damage, and Aβ1-42 induced neurotoxicity, which validated its neuroprotective effectiveness. F24 exhibited efficacy in an in vivo Drosophila model by rescuing eye phenotypes from degeneration caused by Aβ toxicity. Further, computational studies were carried out to monitor the interaction between F24 and Aβ1-42 aggregates. The computational studies corroborated our in vitro and in vivo studies suggesting Aβ1-42 aggregation modulation ability of F24. The brain entry ability of F24 was studied in the parallel artificial membrane permeability assay. Finally, F24 was tested at doses of 1 and 2.5 mg/kg in the Morris water maze AD model. The neuroprotective properties shown by F24 strongly suggest that multifunctional features of this molecule provide symptomatic relief and act as a disease-modifying agent in the treatment of AD. The results from our experiments strongly indicated that natural template-based F24 could serve as a lead molecule for further investigation to explore multifunctional therapeutic agents for AD management.
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Affiliation(s)
- Yash Pal Singh
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005, India
| | - Navneet Kumar
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar, 160062 Punjab, India
| | - Khushbu Priya
- Department of Molecular and Human Genetics, Institute of Science, Banaras Hindu University, Varanasi 221005, India
| | - Brijesh Singh Chauhan
- Department of Biochemistry, Institute of Science, Banaras Hindu University, Varanasi 221005, India
| | - Gauri Shankar
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005, India
| | - Saroj Kumar
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi 110029, India
| | - Gireesh Kumar Singh
- Department of Pharmacy, School of Health Science, Central University of South Bihar, Gaya, 824236 Bihar, India
| | - Saripella Srikrishna
- Department of Biochemistry, Institute of Science, Banaras Hindu University, Varanasi 221005, India
| | - Prabha Garg
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar, 160062 Punjab, India
| | - Gourav Singh
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005, India
| | - Geeta Rai
- Department of Molecular and Human Genetics, Institute of Science, Banaras Hindu University, Varanasi 221005, India
| | - Gyan Modi
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005, India
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Modi G, Marqus GM, Vippila MR, Gollapalli DR, Kim Y, Manna AC, Chacko S, Maltseva N, Wang X, Cullinane RT, Zhang Y, Kotler JLM, Kuzmic P, Zhang M, Lawson AP, Joachimiak A, Cheung A, Snider BB, Rothstein DM, Cuny GD, Hedstrom L. The Enzymatic Activity of Inosine 5'-Monophosphate Dehydrogenase May Not Be a Vulnerable Target for Staphylococcus aureus Infections. ACS Infect Dis 2021; 7:3062-3076. [PMID: 34590817 DOI: 10.1021/acsinfecdis.1c00342] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Many bacterial pathogens, including Staphylococcus aureus, require inosine 5'-monophosphate dehydrogenase (IMPDH) for infection, making this enzyme a promising new target for antibiotics. Although potent selective inhibitors of bacterial IMPDHs have been reported, relatively few have displayed antibacterial activity. Here we use structure-informed design to obtain inhibitors of S. aureus IMPDH (SaIMPDH) that have potent antibacterial activity (minimal inhibitory concentrations less than 2 μM) and low cytotoxicity in mammalian cells. The physicochemical properties of the most active compounds were within typical Lipinski/Veber space, suggesting that polarity is not a general requirement for achieving antibacterial activity. Five compounds failed to display activity in mouse models of septicemia and abscess infection. Inhibitor-resistant S. aureus strains readily emerged in vitro. Resistance resulted from substitutions in the cofactor/inhibitor binding site of SaIMPDH, confirming on-target antibacterial activity. These mutations decreased the binding of all inhibitors tested, but also decreased catalytic activity. Nonetheless, the resistant strains had comparable virulence to wild-type bacteria. Surprisingly, strains expressing catalytically inactive SaIMPDH displayed only a mild virulence defect. Collectively these observations question the vulnerability of the enzymatic activity of SaIMPDH as a target for the treatment of S. aureus infections, suggesting other functions of this protein may be responsible for its role in infection.
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Affiliation(s)
- Gyan Modi
- Department of Biology, Brandeis University, Waltham, Massachusetts 02453, United States
| | - Gary M. Marqus
- Graduate Program in Chemistry, Brandeis University, Waltham Massachusetts 02453, United States
| | - Mohana Rao Vippila
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Health Building 2, 4849 Calhoun Rd., Houston, Texas 77204, United States
| | | | - Youngchang Kim
- Center for Structural Genomics of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, Illinois 60667, United States
- The Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Adhar C. Manna
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire 03755, United States
| | - Shibin Chacko
- Department of Biology, Brandeis University, Waltham, Massachusetts 02453, United States
| | - Natalia Maltseva
- Center for Structural Genomics of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, Illinois 60667, United States
- The Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Xingyou Wang
- Graduate Program in Chemistry, Brandeis University, Waltham Massachusetts 02453, United States
| | - Ryan T. Cullinane
- Department of Biochemistry, Brandeis University, Massachusetts 02453, United States
| | - Yubo Zhang
- Department of Biochemistry, Brandeis University, Massachusetts 02453, United States
| | - Judy L. M. Kotler
- Graduate Program in Biochemistry and Biophysics, Brandeis University, Waltham, Massachusetts 02453, United States
| | - Petr Kuzmic
- BioKin Ltd., Watertown, Massachusetts 02472, United States
| | - Minjia Zhang
- Department of Biology, Brandeis University, Waltham, Massachusetts 02453, United States
| | - Ann P. Lawson
- Department of Biology, Brandeis University, Waltham, Massachusetts 02453, United States
| | - Andrzej Joachimiak
- Center for Structural Genomics of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, Illinois 60667, United States
- The Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois 60367, United States
| | - Ambrose Cheung
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire 03755, United States
| | - Barry B. Snider
- Department of Chemistry, Brandeis University, Waltham, Massachusetts 02453, United States
| | - David M. Rothstein
- David Rothstein Consulting, LLC, Lexington, Massachusetts 02421, United States
| | - Gregory D. Cuny
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Health Building 2, 4849 Calhoun Rd., Houston, Texas 77204, United States
| | - Lizbeth Hedstrom
- Department of Biology, Brandeis University, Waltham, Massachusetts 02453, United States
- Department of Chemistry, Brandeis University, Waltham, Massachusetts 02453, United States
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11
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Singh YP, Rai H, Singh G, Singh GK, Mishra S, Kumar S, Srikrishna S, Modi G. A review on ferulic acid and analogs based scaffolds for the management of Alzheimer's disease. Eur J Med Chem 2021; 215:113278. [PMID: 33662757 DOI: 10.1016/j.ejmech.2021.113278] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 01/30/2021] [Accepted: 01/30/2021] [Indexed: 12/17/2022]
Abstract
Alzheimer's disease (AD) is an age-related multifactorial neurodegenerative disorder characterized by severe central cholinergic neuronal loss, gradually contributing to cognitive dysfunction and impaired motor activity, resulting in the brain's cell death at the later stages of AD. Although the etiology of AD is not well understood, however, several factors such as oxidative stress, deposition of amyloid-β (Aβ) peptides to form Aβ plaques, intraneuronal accumulation of hyperphosphorylated tau protein, and low level of acetylcholine are thought to play a major role in the pathogenesis of AD. There is practically no drug for AD treatment that can address the basic factors responsible for the neurodegeneration and slow down the disease progression. The currently available therapies for AD in the market focus on providing only symptomatic relief without addressing the aforesaid basic factors responsible for the neurodegeneration. Ferulic acid (FA) is a phenol derivative from natural sources and serves as a potential pharmacophore that exerts multiple pharmacological properties such as antioxidant, neuroprotection, Aβ aggregation modulation, and anti-inflammatory. Several FA based hybrid analogs are under investigation as a multi-target directed ligand (MTDLs) to develop novel hybrid compounds for the treatment of AD. In the present review article, we are focused on the critical pathogenic factors responsible for the onset of AD followed by the developments of FA pharmacophore-based hybrids compounds as a novel multifunctional therapeutic agent to address the limitations associated with available treatment for AD. The rationale behind the development of these compounds and their pharmacological activities in particular to their ChE inhibition (ChEI), neuroprotection, antioxidant property, Aβ aggregation modulation, and metal chelation ability, are discussed in detail. We have also discussed the discovery of caffeic and cinnamic acids based MTDLs for AD. This review paper provides an in-depth insight into the research progress and current status of these novel therapeutics in AD and prospects for developing a druggable molecule with desired pharmacological affinity and reduced toxicity for the management of AD.
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Affiliation(s)
- Yash Pal Singh
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Himanshu Rai
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Gourav Singh
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Gireesh Kumar Singh
- Department of Pharmacy, School of Health Science, Central University of South Bihar Gaya, 824236, India
| | - Sunil Mishra
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Saroj Kumar
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, 110029, India
| | - S Srikrishna
- Department of Biochemistry, Institute of Science, Banaras Hindu University, Varanasi, 221005, India
| | - Gyan Modi
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India.
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12
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Rai H, Barik A, Singh YP, Suresh A, Singh L, Singh G, Nayak UY, Dubey VK, Modi G. Molecular docking, binding mode analysis, molecular dynamics, and prediction of ADMET/toxicity properties of selective potential antiviral agents against SARS-CoV-2 main protease: an effort toward drug repurposing to combat COVID-19. Mol Divers 2021; 25:1905-1927. [PMID: 33582935 PMCID: PMC7882058 DOI: 10.1007/s11030-021-10188-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 01/19/2021] [Indexed: 12/16/2022]
Abstract
The importance of the main protease (Mpro) enzyme of SARS-CoV-2 in the digestion of viral polyproteins introduces Mpro as an attractive drug target for antiviral drug design. This study aims to carry out the molecular docking, molecular dynamics studies, and prediction of ADMET properties of selected potential antiviral molecules. The study provides an insight into biomolecular interactions to understand the inhibitory mechanism and the spatial orientation of the tested ligands and further, identification of key amino acid residues within the substrate-binding pocket that can be applied for structure-based drug design. In this regard, we carried out molecular docking studies of chloroquine (CQ), hydroxychloroquine (HCQ), remdesivir (RDV), GS441524, arbidol (ARB), and natural product glycyrrhizin (GA) using AutoDock 4.2 tool. To study the drug-receptor complex's stability, selected docking possesses were further subjected to molecular dynamics studies with Schrodinger software. The prediction of ADMET/toxicity properties was carried out on ADMET Prediction™. The docking studies suggested a potential role played by CYS145, HIS163, and GLU166 in the interaction of molecules within the active site of COVID-19 Mpro. In the docking studies, RDV and GA exhibited superiority in binding with the crystal structure of Mpro over the other selected molecules in this study. Spatial orientations of the molecules at the active site of Mpro exposed the significance of S1–S4 subsites and surrounding amino acid residues. Among GA and RDV, RDV showed better and stable interactions with the protein, which is the reason for the lesser RMSD values for RDV. Overall, the present in silico study indicated the direction to combat COVID-19 using FDA-approved drugs as promising agents, which do not need much toxicity studies and could also serve as starting points for lead optimization in drug discovery.
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Affiliation(s)
- Himanshu Rai
- Room # 23, Department of Pharmaceutical Engineering and Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, Uttar Pradesh, 221005, India
| | - Atanu Barik
- Room # 23, Department of Pharmaceutical Engineering and Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, Uttar Pradesh, 221005, India
| | - Yash Pal Singh
- Room # 23, Department of Pharmaceutical Engineering and Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, Uttar Pradesh, 221005, India
| | - Akhil Suresh
- Department of Pharmaceutics, Manipal College of Pharmaceutical Sciences (MCOPS), Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India
| | - Lovejit Singh
- Room # 23, Department of Pharmaceutical Engineering and Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, Uttar Pradesh, 221005, India
| | - Gourav Singh
- Room # 23, Department of Pharmaceutical Engineering and Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, Uttar Pradesh, 221005, India
| | - Usha Yogendra Nayak
- Department of Pharmaceutics, Manipal College of Pharmaceutical Sciences (MCOPS), Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India.,Manipal McGill Centre for Infectious Diseases, Prasanna School of Public Health, Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India
| | - Vikash Kumar Dubey
- School of Biochemical Engineering, Indian Institute of Technology (Banaras Hindu University), Varanasi, Uttar Pradesh, 221005, India
| | - Gyan Modi
- Room # 23, Department of Pharmaceutical Engineering and Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, Uttar Pradesh, 221005, India.
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13
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Kumar N, Gahlawat A, Kumar RN, Singh YP, Modi G, Garg P. Drug repurposing for Alzheimer’s disease: in silico and in vitro investigation of FDA-approved drugs as acetylcholinesterase inhibitors. J Biomol Struct Dyn 2020; 40:2878-2892. [DOI: 10.1080/07391102.2020.1844054] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Navneet Kumar
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S. Nagar, Mohali, Punjab, India
| | - Anuj Gahlawat
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S. Nagar, Mohali, Punjab, India
| | - Rajaram Naresh Kumar
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S. Nagar, Mohali, Punjab, India
| | - Yash Pal Singh
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, Uttar Pradesh, India
| | - Gyan Modi
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, Uttar Pradesh, India
| | - Prabha Garg
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S. Nagar, Mohali, Punjab, India
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14
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Singh YP, Tej GNVC, Pandey A, Priya K, Pandey P, Shankar G, Nayak PK, Rai G, Chittiboyina AG, Doerksen RJ, Vishwakarma S, Modi G. Design, synthesis and biological evaluation of novel naturally-inspired multifunctional molecules for the management of Alzheimer's disease. Eur J Med Chem 2020; 198:112257. [PMID: 32375073 DOI: 10.1016/j.ejmech.2020.112257] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Revised: 03/17/2020] [Accepted: 03/18/2020] [Indexed: 11/17/2022]
Abstract
In our overall goal to overcome the limitations associated with natural products for the management of Alzheimer's disease and to develop in-vivo active multifunctional cholinergic inhibitors, we embarked on the development of ferulic acid analogs. A systematic SAR study to improve upon the cholinesterase inhibition of ferulic acid with analogs that also had lower logP was carried out. Enzyme inhibition and kinetic studies identified compound 7a as a lead molecule with preferential acetylcholinesterase inhibition (AChE IC50 = 5.74 ± 0.13 μM; BChE IC50 = 14.05 ± 0.10 μM) compared to the parent molecule ferulic acid (% inhibition of AChE and BChE at 20 μM, 15.19 ± 0.59 and 19.73 ± 0.91, respectively). Molecular docking and dynamics studies revealed that 7a fits well into the active sites of AChE and BChE, forming stable and strong interactions with key residues Asp74, Trp286, and Tyr337 in AChE and with Tyr128, Trp231, Leu286, Ala328, Phe329, and Tyr341 in BChE. Compound 7a was found to be an efficacious antioxidant in a DPPH assay (IC50 = 57.35 ± 0.27 μM), and it also was able to chelate iron. Data from atomic force microscopy images demonstrated that 7a was able to modulate aggregation of amyloid β1-42. Upon oral administration, 7a exhibited promising in-vivo activity in the scopolamine-induced AD animal model and was able to improve spatial memory in cognitive deficit mice in the Y-maze model. Analog 7a could effectively reverse the increased levels of AChE and BChE in scopolamine-treated animals and exhibited potent ex-vivo antioxidant properties. These findings suggest that 7a can act as a lead molecule for the development of naturally-inspired multifunctional molecules for the management of Alzheimer's and other neurodegenerative disorders.
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Affiliation(s)
- Yash Pal Singh
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Gullanki Naga Venkata Charan Tej
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Amruta Pandey
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Khushbu Priya
- Department of Molecular and Human Genetics, Institute of Science, Banaras Hindu University, Varanasi, 221005, India
| | - Pankaj Pandey
- National Center for Natural Products Research, University of Mississippi, University, MS, 38677, United States
| | - Gauri Shankar
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Prasanta Kumar Nayak
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Geeta Rai
- Department of Molecular and Human Genetics, Institute of Science, Banaras Hindu University, Varanasi, 221005, India
| | - Amar G Chittiboyina
- National Center for Natural Products Research, University of Mississippi, University, MS, 38677, United States
| | - Robert J Doerksen
- Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, University, MS, 38677, United States
| | - Swati Vishwakarma
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Gyan Modi
- Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India.
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Abstract
Purpose: Post-traumatic CSF leaks are a complication in 2% of all head injuries. Majority of these patients will recover spontaneously. Whilst recent literature has predominantly centred on CSF leaks and their general investigations and management thereof, there is a paucity of information when it comes to those patients who have persistent post-traumatic CSF leaks, as well as the complication of recurrent meningitis. We present a patient with a persistent post-traumatic CSF leak who presented with recurrent bacterial meningitis thirteen times- the highest documented amount in an adult. We reviewed the literature with regards to the above as well.Material and Methods: We reviewed a vast array of journal articles on the topic of CSF leaks from the PubMed resource, and focused this review specifically on those that documented patients who had uncorrected CSF leaks and their outcomes.Results: Complications include meningitis and rhinorrhoea with brain abscesses and pneumocephalus occurring less frequently. Mortality has been documented to be 9% after 1 year. The rates of persistent CSF leaks were within the same range with an average calculated rate of 21%. Whilst meningitis was recorded and is common, it was not stipulated whether the incidences were recurrent.Conclusion: Post-traumatic persistent CSF leaks remain a therapeutic challenge and continued follow-up with early surgical intervention is highly recommended to prevent complications. One of the more serious complications of a persistent leak is meningitis. The long-term outcomes of recurrent meningitis could include cumulative focal neurological deficitis and cognitive impairment.
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Affiliation(s)
- A J Soni
- Department of Neurology, University of Witwatersrand, Johannesburg, South Africa
| | - G Modi
- Department of Neurology, University of Witwatersrand, Johannesburg, South Africa
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16
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Kumar D, Ganeshpurkar A, Kumar D, Modi G, Gupta SK, Singh SK. Secretase inhibitors for the treatment of Alzheimer's disease: Long road ahead. Eur J Med Chem 2018; 148:436-452. [DOI: 10.1016/j.ejmech.2018.02.035] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 01/30/2018] [Accepted: 02/10/2018] [Indexed: 10/18/2022]
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17
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Wei Y, Kuzmič P, Yu R, Modi G, Hedstrom L. Inhibition of Inosine-5'-monophosphate Dehydrogenase from Bacillus anthracis: Mechanism Revealed by Pre-Steady-State Kinetics. Biochemistry 2016; 55:5279-88. [PMID: 27541177 DOI: 10.1021/acs.biochem.6b00265] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Inosine-5'-monophosphate dehydrogenase (IMPDH) catalyzes the conversion of inosine 5'-monophosphate (IMP) to xanthosine 5'-monophosphate (XMP). The enzyme is an emerging target for antimicrobial therapy. The small molecule inhibitor A110 has been identified as a potent and selective inhibitor of IMPDHs from a variety of pathogenic microorganisms. A recent X-ray crystallographic study reported that the inhibitor binds to the NAD(+) cofactor site and forms a ternary complex with IMP. Here we report a pre-steady-state stopped-flow kinetic investigation of IMPDH from Bacillus anthracis designed to assess the kinetic significance of the crystallographic results. Stopped-flow kinetic experiments defined nine microscopic rate constants and two equilibrium constants that characterize both the catalytic cycle and details of the inhibition mechanism. In combination with steady-state initial rate studies, the results show that the inhibitor binds with high affinity (Kd ≈ 50 nM) predominantly to the covalent intermediate on the reaction pathway. Only a weak binding interaction (Kd ≈ 1 μM) is observed between the inhibitor and E·IMP. Thus, the E·IMP·A110 ternary complex, observed by X-ray crystallography, is largely kinetically irrelevant.
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Affiliation(s)
- Yang Wei
- Department of Biology, Brandeis University , Waltham, Massachusetts 02454, United States
| | - Petr Kuzmič
- Department of Biology, Brandeis University , Waltham, Massachusetts 02454, United States.,BioKin Ltd. , Watertown, Massachusetts 02472, United States
| | - Runhan Yu
- Department of Chemistry, Brandeis University , Waltham, Massachusetts 02454, United States
| | - Gyan Modi
- Department of Biology, Brandeis University , Waltham, Massachusetts 02454, United States
| | - Lizbeth Hedstrom
- Department of Biology, Brandeis University , Waltham, Massachusetts 02454, United States.,Department of Chemistry, Brandeis University , Waltham, Massachusetts 02454, United States
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18
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Hari KR, Modi MR, Mochan AHD, Modi G. Reduced risk of toxoplasma encephalitis in HIV-infected patients – a prospective study from Gauteng, South Africa. Int J STD AIDS 2016; 18:555-8. [PMID: 17686219 DOI: 10.1258/095646207781439829] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Toxoplasma seroprevalence was determined in 307 consecutive HIV-infected medical inpatients at the Helen Joseph Hospital, Johannesburg, South Africa, using an enzyme linked immunosorbent assay to detect immunoglobulin G (IgG) and IgM antibodies. The mean age of patients was 36 years, with a female to male ratio of 1.3 to 1. The mean CD4 count was 109 cells/mL. Toxoplasma antibodies were detected in 25 patients (8%). Twenty-two of these patients were IgG positive and IgM negative, i.e. reactivation toxoplasmosis. Only two patients (0.65%) had clinical manifestations of toxoplasmosis (one toxoplasma encephalitis and one retinitis). The risk for toxoplasma encephalitis (TE) was 0.33%. These results indicate that the toxoplasma seroprevalence and the TE risk in this population is low. The implication from this study is that in HIV-infected populations where the toxoplasma seroprevalence is low, the TE risk will be low and empiric treatment of focal brain lesions with anti-toxoplasma therapy may be inappropriate.
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Affiliation(s)
- K R Hari
- Division of Neurology, Department of Neurosciences, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
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19
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Das B, Modi G, Dutta A. Dopamine D3 agonists in the treatment of Parkinson's disease. Curr Top Med Chem 2015; 15:908-26. [PMID: 25832718 DOI: 10.2174/156802661510150328223428] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 10/21/2014] [Accepted: 11/05/2014] [Indexed: 11/22/2022]
Abstract
Parkinson's disease (PD) is t he second most common form of neurodegenerative disorders that results from the progressive loss of dopaminergic neurons in the midbrain substantia nigra pars compacta (SNpc) triggering profound motor perturbation, as well as cognitive, sensory and mood deficits. Although these symptoms can be improved using currently available dopamine replacement strategies, they are not able to slow the neurodegenerative process that underlies PD progression. Following the discovery of the D3 receptor from molecular cloning, it has gained much attention as a potential therapeutic target for the treatment of PD due to their localization in the limbic regions of the brain as well as pharmacologic similarity to the D2 receptor subtype. Of particular interest, D3 receptor-selective agonists appear to have neuroprotective effects apart from their ability to relieve PD symptoms. Owing to the distinct significance of D3 receptor in mediating diverse neurological effects, it represents a unique target for therapeutic intervention in PD with much less undesirable side effects. Herein, we review progress in the development of D3 receptor-selective agonist molecules having a broad spectrum of affinities, selectivities as well as unique pharmacological properties directed at slowing the neurodegeneration process.
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Affiliation(s)
| | | | - Aloke Dutta
- Department of Pharmaceutical Sciences, Wayne State University, Detroit, MI 48202,USA.
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20
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21
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Makowska-Grzyska M, Kim Y, Gorla SK, Wei Y, Mandapati K, Zhang M, Maltseva N, Modi G, Boshoff HI, Gu M, Aldrich C, Cuny GD, Hedstrom L, Joachimiak A. Mycobacterium tuberculosis IMPDH in Complexes with Substrates, Products and Antitubercular Compounds. PLoS One 2015; 10:e0138976. [PMID: 26440283 PMCID: PMC4594927 DOI: 10.1371/journal.pone.0138976] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Accepted: 09/07/2015] [Indexed: 11/30/2022] Open
Abstract
Tuberculosis (TB) remains a worldwide problem and the need for new drugs is increasingly more urgent with the emergence of multidrug- and extensively-drug resistant TB. Inosine 5’-monophosphate dehydrogenase 2 (IMPDH2) from Mycobacterium tuberculosis (Mtb) is an attractive drug target. The enzyme catalyzes the conversion of inosine 5’-monophosphate into xanthosine 5’-monophosphate with the concomitant reduction of NAD+ to NADH. This reaction controls flux into the guanine nucleotide pool. We report seventeen selective IMPDH inhibitors with antitubercular activity. The crystal structures of a deletion mutant of MtbIMPDH2 in the apo form and in complex with the product XMP and substrate NAD+ are determined. We also report the structures of complexes with IMP and three structurally distinct inhibitors, including two with antitubercular activity. These structures will greatly facilitate the development of MtbIMPDH2-targeted antibiotics.
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Affiliation(s)
- Magdalena Makowska-Grzyska
- Center for Structural Genomics of Infectious Diseases, University of Chicago, Chicago, IL, United States of America
| | - Youngchang Kim
- Center for Structural Genomics of Infectious Diseases, University of Chicago, Chicago, IL, United States of America
- Structural Biology Center, Biosciences, Argonne National Laboratory, 9700 S Cass Ave. Argonne, IL, United States of America
| | - Suresh Kumar Gorla
- Department of Biology, Brandeis University, 415 South St. Waltham, MA, United States of America
| | - Yang Wei
- Department of Biology, Brandeis University, 415 South St. Waltham, MA, United States of America
| | - Kavitha Mandapati
- Department of Biology, Brandeis University, 415 South St. Waltham, MA, United States of America
| | - Minjia Zhang
- Department of Biology, Brandeis University, 415 South St. Waltham, MA, United States of America
| | - Natalia Maltseva
- Center for Structural Genomics of Infectious Diseases, University of Chicago, Chicago, IL, United States of America
| | - Gyan Modi
- Department of Biology, Brandeis University, 415 South St. Waltham, MA, United States of America
| | - Helena I. Boshoff
- Tuberculosis Research Section, National Institute of Allergy and Infectious Diseases, Bethesda, MD, United States of America
| | - Minyi Gu
- Center for Structural Genomics of Infectious Diseases, University of Chicago, Chicago, IL, United States of America
| | - Courtney Aldrich
- Center for Drug Design, Academic Health Center, University of Minnesota, 516 Delaware St. SE, Minneapolis, MN, United States of America
| | - Gregory D. Cuny
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, 549A Science and Research Building 2, Houston, TX, United States of America
- Department of Chemistry, Brandeis University, 415 South St. Waltham, MA, United States of America
| | - Lizbeth Hedstrom
- Department of Biology, Brandeis University, 415 South St. Waltham, MA, United States of America
- Department of Chemistry, Brandeis University, 415 South St. Waltham, MA, United States of America
- * E-mail: (LH); (AJ)
| | - Andrzej Joachimiak
- Center for Structural Genomics of Infectious Diseases, University of Chicago, Chicago, IL, United States of America
- Structural Biology Center, Biosciences, Argonne National Laboratory, 9700 S Cass Ave. Argonne, IL, United States of America
- * E-mail: (LH); (AJ)
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Modi G, Voshavar C, Gogoi S, Shah M, Antonio T, Reith MEA, Dutta AK. Multifunctional D2/D3 agonist D-520 with high in vivo efficacy: modulator of toxicity of alpha-synuclein aggregates. ACS Chem Neurosci 2014; 5:700-17. [PMID: 24960209 DOI: 10.1021/cn500084x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
We have developed a series of dihydroxy compounds and related analogues based on our hybrid D2/D3 agonist molecular template to develop multifunctional drugs for symptomatic and neuroprotective treatment for Parkinson's disease (PD). The lead compound (-)-24b (D-520) exhibited high agonist potency at D2/D3 receptors and produced efficacious activity in the animal models for PD. The data from thioflavin T (ThT) assay and from transmission electron microscopy (TEM) analysis demonstrate that D-520 is able to modulate aggregation of alpha-synuclein (αSN). Additionally, coincubation of D-520 with αSN is able to reduce toxicity of preformed aggregates of αSN compared to control αSN alone. Finally, in a neuroprotection study with dopaminergic MN9D cells, D-520 clearly demonstrated the effect of neuroprotection from toxicity of 6-hydroxydopamine. Thus, compound D-520 possesses properties characteristic of multifunctionality conducive to symptomatic and neuroprotective treatment of PD.
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Affiliation(s)
- Gyan Modi
- Department
of Pharmaceutical Sciences, Wayne State University, Detroit, Michigan 48202, United States
| | - Chandrashekhar Voshavar
- Department
of Pharmaceutical Sciences, Wayne State University, Detroit, Michigan 48202, United States
| | - Sanjib Gogoi
- Department
of Pharmaceutical Sciences, Wayne State University, Detroit, Michigan 48202, United States
| | - Mrudang Shah
- Department
of Pharmaceutical Sciences, Wayne State University, Detroit, Michigan 48202, United States
| | | | | | - Aloke K. Dutta
- Department
of Pharmaceutical Sciences, Wayne State University, Detroit, Michigan 48202, United States
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23
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Kumar P, Choonara Y, Modi G, Naidoo D, Pillay V. Cur(Que)min: A neuroactive permutation of Curcumin and Quercetin for treating spinal cord injury. Med Hypotheses 2014; 82:437-41. [DOI: 10.1016/j.mehy.2014.01.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Accepted: 01/18/2014] [Indexed: 11/26/2022]
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24
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Modi G, Antonio T, Reith M, Dutta A. Structural modifications of neuroprotective anti-Parkinsonian (-)-N6-(2-(4-(biphenyl-4-yl)piperazin-1-yl)-ethyl)-N6-propyl-4,5,6,7-tetrahydrobenzo[d]thiazole-2,6-diamine (D-264): an effort toward the improvement of in vivo efficacy of the parent molecule. J Med Chem 2014; 57:1557-72. [PMID: 24471976 PMCID: PMC3983390 DOI: 10.1021/jm401883v] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In our overall goal to develop multifunctional dopamine D2/D3 agonist drugs for the treatment of Parkinson's disease (PD), we previously synthesized potent D3 preferring agonist D-264 (1a), which exhibited neuroprotective properties in two animal models of PD. To enhance the in vivo efficacy of 1a, a structure-activity relationship study was carried out. Competitive binding and [(35)S]GTPγS functional assays identified compound (-)-9b as one of the lead molecules with preferential D3 agonist activity (EC50(GTPγS); D3 = 0.10 nM; D2/D3 (EC50): 159). Compounds (-)-9b and (-)-8b exhibited high in vivo activity in two PD animal models, reserpinized and 6-hydroxydopamine (OHDA)-induced unilateral lesioned rats. On the other hand, 1a failed to show any in vivo activity in these models unless the compound was dissolved in 5-10% beta-hydroxy propyl cyclodextrin solution. Lead compounds exhibited appreciable radical scavenging activity. In vitro experiments with dopaminergic MN9D cells indicated neuroprotection by both 1a and (-)-9b from toxicity of MPP+.
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Affiliation(s)
- Gyan Modi
- Department of Pharmaceutical Sciences, Wayne State University , Detroit, Michigan 48202, United States
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Modi G, Sharma H, Kharkar PS, Dutta AK. Understanding the Structural Requirements of Hybrid (S)-6-((2-(4-Phenylpiperazin-1-yl)ethyl)(propyl)amino)-5,6,7,8-tetrahydronaphthalen-1-ol and its Analogs as D2/D3 Receptor Ligands: A Three-Dimensional Quantitative Structure-Activity Relationship (3D QSAR) Investigation. Medchemcomm 2014; 5:1384-1399. [PMID: 25221669 DOI: 10.1039/c4md00159a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
To gain insights into the structural requirements for dopamine D2 and D3 agonists in the treatment of Parkinson's disease (PD) and to elucidate the basis of selectivity for D3 over D2 (D2/D3), 3D quantitative structure-activity relationship (3D QSAR) investigations using CoMFA (comparative molecular field analysis) and CoMSIA (comparative molecular similarity indices analysis) methods were performed on a series of 45 structurally related D2 and D3 dopaminergic ligands. Two alignment methods (atom-based and flexible) and two charge calculation methods (Gasteiger-Hückel and AM1) were used in the present study. Overall, D2 affinity and selectivity (D2/D3) models performed better with r2cv values of 0.71 and 0.63 for CoMFA and 0.71 and 0.79 for CoMSIA, respectively. The corresponding predictive r2 values for the CoMFA and CoMSIA models were 0.92 and 0.86 and 0.91 and 0.78, respectively. The CoMFA models generated using flexible alignment outperformed the models with the atom-based alignment in terms of relevant statistics and interpretability of the generated contour maps while CoMSIA models obtained using atom-based alignment showed superiority in terms of internal and external predictive abilities. The presence of carbonyl group (C=O) attached to the piperazine ring and the hydrophobic biphenyl ring were found to be the most important features responsible for the D3 selectivity over D2. This study can be further utilized to design and develop selective and potent dopamine agonists to treat PD.
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Affiliation(s)
- Gyan Modi
- Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmaceutical and Health Sciences (EACPHS), Wayne State University, Detroit, MI 48201. USA
| | - Horrick Sharma
- Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmaceutical and Health Sciences (EACPHS), Wayne State University, Detroit, MI 48201. USA
| | - Prashant S Kharkar
- Department of Pharmaceutical Chemistry, SPP School of Pharmacy and Technology Management (SPPSPTM), SVKM's NMIMS, Mumbai-400 056. India
| | - Aloke K Dutta
- Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmaceutical and Health Sciences (EACPHS), Wayne State University, Detroit, MI 48201. USA
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Kumar P, Pillay V, Choonara Y, Toit LD, Modi G, Naidoo D. ISDN2012_0186: A combinatorial
in silico
approach to model the glycosylated nornicotine‐curcumin paradigm in neuroprotection and neurotherapy for Alzheimer's disease. Int J Dev Neurosci 2012. [DOI: 10.1016/j.ijdevneu.2012.10.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Affiliation(s)
- P. Kumar
- Department of Pharmacy and PharmacologyUniversity of the WitwatersrandParktownJohannesburgSouth Africa
| | - V. Pillay
- Department of Pharmacy and PharmacologyUniversity of the WitwatersrandParktownJohannesburgSouth Africa
| | - Y.E. Choonara
- Department of Pharmacy and PharmacologyUniversity of the WitwatersrandParktownJohannesburgSouth Africa
| | - L.C. du Toit
- Department of Pharmacy and PharmacologyUniversity of the WitwatersrandParktownJohannesburgSouth Africa
| | - G. Modi
- Department of NeurologyUniversity of the WitwatersrandParktownJohannesburgSouth Africa
| | - D. Naidoo
- Department of NeurosurgeryUniversity of the WitwatersrandParktownJohannesburgSouth Africa
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Gogoi S, Biswas S, Modi G, Antonio T, Reith MEA, Dutta AK. Novel bivalent ligands for D2/D3 dopamine receptors: Significant co-operative gain in D2 affinity and potency. ACS Med Chem Lett 2012; 3:991-996. [PMID: 23275802 DOI: 10.1021/ml3002117] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
This report describes development of a series of novel bivalent molecules with a pharmacophore derived from the D2/D3 agonist 5-OH-DPAT. Spacer length in the bivalent compounds had a pronounced influence on affinity for D2 receptors. A 23-fold increase of D2 affinity was observed at a spacer length of 9 or 10 (compounds 11d and 14b) compared to monovalent 5-OH-DPAT (Ki; 2.5 and 2.0 vs. 59 nM for 11d and 14b vs. 5-OH-DPAT, respectively). Functional potency of 11d and 14b indicated a 24- and 94-fold increase in potency at the D2 receptor compared to 5-OH-DPAT (EC50; 1.7 and 0.44 vs. 41 nM for 11d and 14b vs. 5-OH-DPAT, respectively). These are the most potent bivalent agonists for D2 receptor known to date. This synergism is consonant with cooperative interaction at the two orthosteric binding sites in the homodimeric receptor.
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Affiliation(s)
- Sanjib Gogoi
- Department of Pharmaceutical Sciences, Wayne State University, Detroit, Michigan 48202, United States
| | - Swati Biswas
- Department of Pharmaceutical Sciences, Wayne State University, Detroit, Michigan 48202, United States
| | - Gyan Modi
- Department of Pharmaceutical Sciences, Wayne State University, Detroit, Michigan 48202, United States
| | | | | | - Aloke K. Dutta
- Department of Pharmaceutical Sciences, Wayne State University, Detroit, Michigan 48202, United States
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Luciani P, Deledda C, Benvenuti S, Cellai I, Modi G, Fibbi B, Danza G, Vannelli GB, Peri A. Relationship between the neuroprotective effects of insulin-like growth factor-1 and 17β-oestradiol in human neuroblasts. J Neuroendocrinol 2012; 24:1304-10. [PMID: 22621285 DOI: 10.1111/j.1365-2826.2012.02343.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Insulin-like growth factor-1 (IGF-1) and oestrogens interact with each other as neuroprotective factors. We have previously demonstrated that 17β-oestradiol protects against β-amyloid and oxidative stress toxicity and increases the amount of cell cholesterol in human foetal neuroblasts (FNC). The present study aimed: (i) to assess the protective effects of IGF-1 in FNC cells; (ii) to investigate the relationship between IGF-1 and 17β-oestradiol; and (iii) to determine whether cholesterol was a major mediator of the effects of IGF-1, similarly to 17β-oestradiol. We found that IGF-1 effectively exerts neuroprotective effects in FNC cells. We also demonstrated that the IGF-1 receptor (IGF-1R) pathway is needed to maintain oestrogen-mediated neuroprotection. Finally, we found that, opposite to 17β-oestradiol, IGF-1 did not cause a significant increase in cell cholesterol. These findings indicate that a cross-talk between IGF-1 and 17β-oestradiol occurs in FNC cells. In particular, the activation of the IGF-1R cascade appears to be fundamental to warrant 17β-oestradiol-mediated neuroprotection, even though cell cholesterol does not play a major role as an effector of this pathway.
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Affiliation(s)
- P Luciani
- Department of Clinical Physiopathology, Center for Research, Transfer and High Education on Chronic, Inflammatory, Degenerative and Neoplastic Disorders for the Development of Novel Therapies-DENOThe, University of Florence, Florence, Italy
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Abstract
BACKGROUND Non-traumatic myelopathy from developing regions has been described widely. In these regions infections, mainly tuberculosis, followed by acute transverse myelitis and neoplasms, dominate. These are also regions of high HIV prevalence. In developed regions, the most prominent reported spinal cord disease in HIV/AIDS is vacuolar myelopathy (VM). Other myelopathy causes in HIV/AIDS include opportunistic infections, neoplasms, vascular lesions and metabolic disease. In developing regions, opportunistic infections are more commonly encountered with VM occurring less frequently. AIM To determine the influence of HIV on the myelopathy spectrum in an HIV endemic region. DESIGN Prospective case series. METHODS Hundred unselected consecutive in-patients admitted with myelopathy were studied. Myelopathy aetiologies were established by collating information obtained from magnetic resonance imaging (MRI) scans, CSF and blood studies, CXR findings, non-neurological illness and response to treatment. Data were analysed in terms of two cohorts, HIV positive and HIV negative. RESULTS Approximately 50% of the patients presenting and admitted to our hospital with non-traumatic myelopathy are HIV positive. The HIV positive myelopathy patients were younger (20-40 years) and had infectious aetiologies. Tuberculosis was the most frequently identified cause of myelopathy. The majority of HIV-positive patients had advanced HIV infection. Anti-retroviral treatment did not influence myelopathy aetiologies. The HIV-negative patients were older and had neoplasms, followed by degenerative spondylosis as the main myelopathy causes. CONCLUSION HIV influences the non-traumatic myelopathy spectrum in regions with high HIV prevalence. Empiric treatment of HIV-myelopathy patients with anti-tuberculous medications where resources are severely limited has merit.
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Affiliation(s)
- G Modi
- Department of Neurosciences, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, 7 York road, Partktown, Johannesburg, Gauteng 2193, South Africa.
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Gopishetty B, Hazeldine S, Santra S, Johnson M, Modi G, Ali S, Zhen J, Reith M, Dutta A. Further structure-activity relationship studies on 4-((((3S,6S)-6-benzhydryltetrahydro-2H-pyran-3-yl)amino)methyl)phenol: identification of compounds with triple uptake inhibitory activity as potential antidepressant agents. J Med Chem 2011; 54:2924-32. [PMID: 21446715 DOI: 10.1021/jm200020a] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
To investigate structural alterations of the lead triple uptake inhibitor molecule, disubstituted 4-((((3S,6S)-6-benzhydryltetrahydro-2H-pyran-3-yl)amino)methyl)phenol, we have carried out structure-activity relationship (SAR) studies to investigate the effect of alteration of aromatic substitutions and introduction of heterocyclic aromatic moieties on this molecular template. The novel compounds were tested for their affinities for the dopamine transporter (DAT), serotonin transporter (SERT), and norepinephrine transporter (NET) in the brain by measuring their potency in inhibiting the uptake of [(3)H]DA, [(3)H]5-HT, and [(3)H]NE, respectively. SAR results indicate dopamine norepinephrine reuptake inhibitory (DNRI) type activity in thiophene (10g) and pyrrole (10i) derivatives. On the other hand, 3-hydroxyphenyl derivative 10f and 4-methoxyphenyl derivative 10j exhibited a triple reuptake inhibitory (TUI) activity profile, as these molecules exhibited potent uptake inhibition for all the monoamine transporters (K(i) of 31.3, 40, 38.5 and K(i) of 15.9, 12.9, 29.3 for DAT, SERT, and NET for 10f and 10g, respectively). Compound 10f was further evaluated in the rat forced swim test to evaluate its potential antidepressant effect. The results show significant reduction of immobility by TUI 10f at 10 mg/kg dose, indicating potential antidepressant activity.
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Affiliation(s)
- Bhaskar Gopishetty
- Department of Pharmaceutical Sciences, Wayne State University, Detroit, Michigan 48202, United States
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Jivan K, Mochan A, Modi G. Intraventricular neurocysticercosis causing acute unilateral hydrocephalus. Afr J Psychiatry (Johannesbg) 2010; 13:315-317. [PMID: 20957333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Affiliation(s)
- K Jivan
- Division of Neurology, Department of Neurosciences, University of the Witwatersrand, Johannesburg, South Africa
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Sibeko B, Pillay V, Choonara YE, Khan RA, Modi G, Iyuke SE, Naidoo D, Danckwerts MP. Computational molecular modeling and structural rationalization for the design of a drug-loaded PLLA/PVA biopolymeric membrane. Biomed Mater 2008; 4:015014. [DOI: 10.1088/1748-6041/4/1/015014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Modi G, Ranchod K, Modi M, Mochan A. Human immunodeficiency virus associated intracranial aneurysms: report of three adult patients with an overview of the literature. J Neurol Neurosurg Psychiatry 2008; 79:44-6. [PMID: 17220288 DOI: 10.1136/jnnp.2006.108878] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND AND PURPOSE Aneurysms have been described in HIV infected patients. These involve predominantly extracranial blood vessels with specific histological and clinical features. Intracranial aneurysms are rare and have been identified mainly in children. METHODS Case reports and literature review. RESULTS Three black South African HIV positive adult patients with intracranial aneurysms were identified. The clinical, laboratory and radiological features are described. CONCLUSIONS Intracranial aneurysms occur in both adults and children infected with HIV. More information is required on this association. The frequency in terms of numbers of cases indicates that it is an uncommon association or manifestation of HIV. The characteristics of the aneurysms suggest that they are distinctive and not a chance or coincidental co-occurrence of congenital or arteriosclerotic aneurysms.
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Affiliation(s)
- G Modi
- Division of Neurology, Department of Neurosciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, PO Box 909, Lenasia, 1820, South Africa.
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Connor MD, Hopkins T, Tollman SM, Thorogood M, Modi G. Blood pressure-measuring devices in rural South Africa: an audit conducted by the SASPI team in the Agincourt field site. Cardiovasc J Afr 2006; 17:192-6. [PMID: 17001422 PMCID: PMC2965368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023] Open
Abstract
BACKGROUND Cardiovascular disease is an important cause of morbidity and mortality in South Africa. The Southern Africa Stroke Prevention Initiative (SASPI) found a high prevalence of stroke in the rural Agincourt subdistrict, Limpopo province. Hypertension is the commonest vascular risk factor in our population and it is essential that primary care services be adequately equipped to detect and treat hypertension. The aim of this study was to assess the number, accuracy and working condition of blood pressure measuring devices (BMD) in the clinics that serve the field site, and to assess the clinic sisters' perceptions of the availability of antihypertensive medication and aspirin. METHODS In each of the clinics serving the site we assessed the BMDs and cuffs using the following criteria: general condition, bladder size, state of rubber components, operation of the inlet valve and control of valve operation. The legibility of the gauge, level and condition of the mercury, and the condition of the glass tube were checked when relevant. The performance of the BMD was then assessed both with the cuff used in the clinic and with a new functioning cuff, against an accurate mercury sphygmomanometer. By interviewing the clinic sister we could assess the availability of antihypertensive medication and aspirin, as well as the state of the drug delivery system. RESULTS All BMDs were mercury sphygmomanometers. Four clinics had one BMD each, one clinic had two, and one clinic had four. In one clinic the device was not functional at all until the study cuff was used. None of the clinics had spare cuffs and only one clinic had access to a large cuff. Nine out of 10 (90%) cuffs tested had unsatisfactory valve function, and none was of the size recommended by the guidelines. Although the condition of the mercury was only considered satisfactory in 40% of BMDs, once a new cuff had been fitted to the BMDs all of them were accurate to within 4 mmHg between 50 and 250 mmHg. Fifty per cent of clinic sisters felt they always had sufficient stock of hydrochlorothiazide and alpha-methyldopa, but the supply of more expensive medication was less reliable. Only one clinic always had sufficient aspirin. CONCLUSION Although none of the primary care clinics had fully functioning BMDs, almost all the defects related to malfunctioning and inappropriately sized cuffs, which would be inexpensive to repair or replace. A procedure for routine servicing or replacement of both BMDs and cuffs is needed, as well as optimisation of medication delivery to remote areas.
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Affiliation(s)
- M D Connor
- Division of Neurology, Department of Neurosciences, University of the Witwatersrand, Johannesburg, South Africa
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Abstract
The purpose of the study was to determine the relevance of protein S deficiency in HIV infected patients with ischaemic stroke. In total, 33 HIV positive patients with ischaemic stroke, previously described by us, were prospectively compared with control groups for occurrence of protein S deficiency. The control groups comprised an equal number of consecutive matched HIV positive and negative patients without and with stroke respectively. Data were analysed in contingency tables using Fisher's exact test. Protein S deficiency occurred significantly more frequently in HIV positive compared with HIV negative stroke patients (p < 0.001). However, by including HIV positive patients without stroke as a control group and comparing this group with the HIV positive stroke group we found that protein S deficiency is statistically related to HIV infection and not stroke occurrence. Our data indicate that the presence of protein S deficiency in HIV positive patients with stroke is an epiphenomenon of HIV infection.
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Affiliation(s)
- A Mochan
- Division of Neurology, Department of Neurosciences, School of Clinical Medicin, Faculty of Health Sciences, University of Witwatersrand, Johannesburg, South Africa
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Modi M, Mochan A, Modi G. Management of HIV-associated focal brain lesions in developing countries - experience at Chris Hani Baragwanath Hospital. SA J Radiol 2005. [DOI: 10.4102/sajr.v9i2.83] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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Modi M, Mochan A, Modi G, Hale MJ. Haemorrhage in intracranial tuberculosis. SA J Radiol 2005. [DOI: 10.4102/sajr.v9i2.85] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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Abstract
BACKGROUND HIV-associated focal brain lesions (HFBL) are caused by opportunistic infections, neoplasms, or cerebrovascular diseases. In developed countries, toxoplasma encephalitis (TE) is the most frequent cause, followed by primary CNS lymphoma (PCNSL). Guidelines based on these causes however are poorly suited to developing countries, where treatable infections predominate as causes of HFBL. AIM To determine a practical approach to the management of HFBL in developing countries. DESIGN Case series. METHODS Patients (n = 32) were managed based on presumed aetiologies of the focal brain lesions, determined by collating information from CT scans, CSF and blood studies, concurrent non-neurological illness and response to treatment. RESULTS The principal presumed cause of HFBL was tuberculosis (69%). The therapeutic response was good in 69% of patients. DISCUSSION In developing countries, infections are the predominant cause of HFBL, the principal causes being infections that are endemic to the populations being studied. Empiric treatment based on limited investigations should be directed according to the nature of such infections. A modified algorithm is proposed.
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Affiliation(s)
- M Modi
- Division of Radiology, Department of Radiation Sciences, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
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Bhowmik D, Padmanabhan S, Dinda A, Modi G, Gupta S, Agarwal SK, Tiwari SC, Dash SC. Hepatitis C virus related cryoglobulinemic glomerulonephritis. J Assoc Physicians India 2002; 50:275-7. [PMID: 12038665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
A 46 years male presented with skin rash and acute nephritic syndrome. He had history of jaundice four months back. Rheumatoid factor and cryoglobulins were present in the serum. Although anti-HCV antibodies were negative, HCV RNA was detected by polymerase chain reaction. Kidney biopsy showed membranoproliferative glomerulonephritis and thrombi in the lumen of the glomerular capillary loops. His renal functions improved with steroids.
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Affiliation(s)
- D Bhowmik
- Department of Nephrology, All India Institute of Medical Sciences, New Delhi
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Modi M, Modi G. New-onset seizures in HIV-infected patients. A review and guide to management. S Afr Med J 2001; 91:1025-6. [PMID: 11845592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Affiliation(s)
- M Modi
- Radiology Division, Department of Radiological Sciences, Neurology Division, Department of Neurosciences, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg
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Abstract
Repeated administration of psychomotor stimulants produces an enduring and progressively enhanced behavioral response known as behavioral sensitization, which has been implicated as a model for psychiatric disorders such as mania, schizophrenia, and drug addiction. The objective of the study was to determine whether lithium chloride (LiCl), an anti-manic agent, is effective in blocking the development and/or the expression of behavioral sensitization to methylphenidate. Male Sprague-Dawley rats (n=64) weighing 170-190 g were randomly divided into seven treatment groups. A computerized animal activity monitor system continuously recorded locomotor activity for 16 days. Effects of LiCl on induction of methylphenidate sensitization were studied by giving LiCl before or during six daily methylphenidate administrations. Effects of LiCl on the expression of methylphenidate sensitization were studied by injecting LiCl after sensitization to methylphenidate was induced. It was shown that LiCl treatment modulated the acute methylphenidate effects by transiently attenuating the locomotor response to methylphenidate during the six daily methylphenidate administrations but neither single nor multiple treatments with LiCl blocked the development or the expression of behavioral sensitization.
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Affiliation(s)
- P Yang
- Department of Neurobiology and Anatomy, The University of Texas Medical School at Houston, PO Box 20708, Houston, TX 77225, USA
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Abstract
PURPOSE To describe the clinical profile of idiopathic optic neuritis in South African blacks. METHODS South African black patients with acute isolated idiopathic optic neuritis, treated and followed for at least 3 months at a large medical centre, were studied. Exclusion criteria were other causes of optic neuropathy (such as ischaemic optic neuropathy, toxins or Leber's hereditary optic neuropathy); all causes of optic neuritis (such as HIV, neurosyphilis, sarcoid or connective tissue disease); neurological disease outside of the optic nerves; and any race other than South African black. Patients underwent extensive ophthalmic, neurological, radiological, cerebrospinal fluid and blood assessment. RESULTS Eighteen eyes of 10 patients were studied. The mean age was 35.7 years and 9 patients were female. Only 2 patients had truly unilateral optic neuritis, the other 8 having either bilaterally simultaneous or consecutive disease. Presenting visual acuity (VA) was less than 6/60 in 17 of 18 eyes, with severe dyschromatopsia in all eyes. Fifteen eyes had optic disc swelling. All patients were treated with corticosteroids. After at least 3 months follow-up only 6 eyes recovered VA of 6/12 or better, with only 3 eyes recovering colour vision of 10/13 or better on Ishihara plate testing. No patient had multiple sclerosis (MS) on presentation, nor developed MS on follow-up. CONCLUSION Idiopathic optic neuritis in black South Africans differs from that in whites. The higher prevalence of bilateral cases and of optic disc swelling, the weaker association with MS and the extremely poor visual outcome distinguish optic neuritis in black South Africans.
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Affiliation(s)
- R Pokroy
- Department of Neurology, Baragwanath Chris Hani Hospital, University of Witwatersrand, Johannesburg-Soweto, South Africa.
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Abstract
Adenosine and AMP in the salivary glands of the sand fly Phlebotomus argentipes were characterized by reversed-phase high-pressure liquid chromatography with diode-array detection and mass spectrometry. AMP and adenosine were measured in individual salivary gland pairs, yielding 76.8 +/- 8.6 and 380 +/- 25 pmoles per pair of salivary glands, respectively (mean +/- SE, n = 12). These values decrease to 45 +/- 7 and 181 +/- 21 pmoles following a blood meal, indicating that AMP and adenosine were secreted. Because adenosine and AMP have anti-platelet, vasodilatory, and immunomodulatory properties, it is proposed that these salivary nucleotides help the fly to blood feed and may affect Leishmania transmission.
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Affiliation(s)
- J M Ribeiro
- Section of Medical Entomology, Laboratory of Parasitic Diseases, Bethesda, Maryland 20892-0425, USA
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Abstract
OBJECTIVES To investigate the nature and cause in eight black South African patients of a recurrent (multiphasic), remitting, and relapsing demyelinating disease of the CNS. METHODS The clinical and laboratory investigations and radiological manifestations of these patients were documented. RESULTS Each patient had two or more acute attacks of demyelinating disease affecting the CNS. The clinical presentations of the patients were predominantly those of multiphasic neuromyelitis optica (NMO). Brain MRI in these patients showed features consistent with those described for acute disseminated encephalomyelitis (ADEM), as well as lesions that are described in multiple sclerosis. There was involvement of the corpus callosum in addition to typical ADEM lesions. Laboratory investigations excluded all other known causes of multiphasic CNS demyelination. Oligoclonal antibodies were not detected in these patients at any time. The patients were all from a population with a low risk for MS (black South Africans). CONCLUSION The patients described here represent a new phenotypic expression of a recurrent (multiphasic), steroid sensitive, inflammatory demyelinating disorder of the CNS occurring in black South Africans. The disorder is either a distinct inflammatory demyelinating disorder of the CNS of as yet unknown aetiology, or a varied form of MS (ADEM/NMO) occurring in a population with a low risk (where the genetic trait and environmental risk factors for MS do not exist) for MS.
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Affiliation(s)
- G Modi
- Neurology Unit, Department of Medicine, Chris Hani Baragwanath Hospital, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
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Abstract
The authors studied new-onset seizures in 60 heterosexual black South African HIV-infected patients who had not used IV drugs. An intracranial space-occupying lesion was identified in 53% of patients, meningitis in 22%, and no additional cause in 25%. Of the patients with an identifiable cause, 64% had probable tuberculosis (tuberculoma or tuberculous meningitis). The majority of patients had late-stage HIV infection (CD4 counts <200/mm(3)).
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Affiliation(s)
- G Modi
- Neurology Unit, Department of Medicine, Chris Hani Baragwanath Hospital, and the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
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46
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Abstract
Despite the fact that Leishmania are transmitted exclusively by sand flies, none of the experimental models of leishmaniasis have established infection via sand fly bites. Here we describe a reproducible murine model of Leishmania major infection transmitted by Phlebotomus papatasi. Prior exposure of mice to bites of uninfected sand flies conferred powerful protection against Leishmania major that was associated with a strong delayed-type hypersensitivity response and with interferon-gamma production at the site of parasite delivery. These results have important implications for the epidemiology of cutaneous leishmaniasis and suggest a vaccination strategy against this and possibly other vector-borne diseases.
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Affiliation(s)
- S Kamhawi
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
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47
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Abstract
A 25-year-old woman with a history of chronic severe migraine with aura presented in an apoplectic state 1 week after the delivery of her third child. She developed a severe headache and within hours lapsed into a coma. A CT scan of the brain showed cerebral edema and an occipital hemorrhage. A four-vessel angiogram showed diffuse arterial narrowing of all the intracranial vessels with segmental narrowing of the suprasellar portion of the internal carotid arteries bilaterally. She had no risk factors for stroke or vasculitis. Her pregnancy and delivery were uneventful with no preeclampsia or eclampsia. Apart from ergometrine at the time of the delivery, no vasoconstrictor drugs were used. She recovered spontaneously. Serial CT scans of the brain demonstrated resolution of the edema and hemorrhage with the development of cortical and watershed infarcts. A repeat cerebral angiogram was normal. She was, therefore, diagnosed as having suffered from postpartum cerebral angiopathy, a form of reversible cerebral vasoconstriction, called the Call or Call-Fleming syndrome. The relationship between migraine and postpartum angiopathy in the development of reversible cerebral vasoconstriction is discussed.
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Affiliation(s)
- M Modi
- Department of Radiology and the Neurology Unit, Department of Medicine, the Chris Hani Baragwanath Hospital and the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
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48
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Lira R, Doherty M, Modi G, Sacks D. Evolution of lesion formation, parasitic load, immune response, and reservoir potential in C57BL/6 mice following high- and low-dose challenge with Leishmania major. Infect Immun 2000; 68:5176-82. [PMID: 10948141 PMCID: PMC101773 DOI: 10.1128/iai.68.9.5176-5182.2000] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A model of cutaneous leishmaniasis using 10(2) Leishmania major metacyclic promastigotes inoculated into the footpads of genetically resistant C57BL/6 mice was studied in order to more accurately reproduce the evolution of lesion formation and the kinetics of parasite growth and immune response as they might occur in naturally exposed reservoirs and in human hosts. In contrast to the more conventional experimental model employing 10(6) metacyclic promastigotes, in which the rapid development of footpad lesions was associated with an increasing number of amastigotes in the site, the low-dose model revealed a remarkably "silent" phase of parasite growth, lasting approximately 6 weeks, during which peak parasitic loads were established in the absence of any overt pathology. Footpad swelling was observed after 6 weeks, coincident with the onset of parasite clearance and with production of high levels of interleukin-12 (IL-12) and gamma interferon (IFN-gamma) in draining lymph nodes. Low-dose challenge of IL-12- and IFN-gamma-depleted or -deficient mice provided strong evidence that the induction or expression of cellular immunity is essentially absent during the first 6 to 8 weeks of intracellular growth, since the concentration of amastigotes in the site was not enhanced compared to that for wild-type animals during this time. By monitoring the ability of infected mice to transmit parasites to vector sand flies, it was observed that following low-dose challenge, footpads without apparent lesions provided an efficient source of parasites for exposed flies and that the low-dose challenge actually extended the duration of parasite transmissibility during the course of infection.
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Affiliation(s)
- R Lira
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
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49
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Abstract
Fifteen patients with primary hypothyroidism were evaluated neurologically. Needle biopsies of skeletal muscle were obtained using a Bergstrom needle. In 73% of the patients, cores were identified histologically and by electron microscopy in the skeletal muscle of these patients. The presence of cores correlated with the severity of hypothyroidism, muscle hypertrophy, cramps and the duration of the hypothyroid state. There was no significant correlation with muscle weakness. Immunofluorescence studies with N-CAM antibodies demonstrated staining of the sarcolemma, cytoplasm and central regions (cores) in the hypothyroid muscle. These imply that the presence of cores in hypothyroid myopathy is due to reactivation of embryonic proteins that disrupt skeletal muscle architecture.
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Affiliation(s)
- G Modi
- Neurology Unit, Department of Medicine, Chris Hani Baragwanath Hospital, Johannesburg, South Africa
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50
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Modi G, Modi M. Cold agglutinins and cryoglobulins in a patient with acute aortoarteritis (Takayasu's disease) and tuberculous lymphadenitis. Rheumatology (Oxford) 2000; 39:337-8. [PMID: 10788549 DOI: 10.1093/rheumatology/39.3.337] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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