1
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Khan SS, Khatik GL, Datusalia AK. Strategies for Treatment of Disease-Associated Dementia Beyond Alzheimer's Disease: An Update. Curr Neuropharmacol 2023; 21:309-339. [PMID: 35410602 PMCID: PMC10190146 DOI: 10.2174/1570159x20666220411083922] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 02/27/2022] [Accepted: 04/03/2022] [Indexed: 11/22/2022] Open
Abstract
Memory, cognition, dementia, and neurodegeneration are complexly interlinked processes with various mechanistic pathways, leading to a range of clinical outcomes. They are strongly associated with pathological conditions like Alzheimer's disease, Parkinson's disease, schizophrenia, and stroke and are a growing concern for their timely diagnosis and management. Several cognitionenhancing interventions for management include non-pharmacological interventions like diet, exercise, and physical activity, while pharmacological interventions include medicinal agents, herbal agents, and nutritional supplements. This review critically analyzed and discussed the currently available agents under different drug development phases designed to target the molecular targets, including cholinergic receptor, glutamatergic system, GABAergic targets, glycine site, serotonergic targets, histamine receptors, etc. Understanding memory formation and pathways involved therein aids in opening the new gateways to treating cognitive disorders. However, clinical studies suggest that there is still a dearth of knowledge about the pathological mechanism involved in neurological conditions, making the dropouts of agents from the initial phases of the clinical trial. Hence, a better understanding of the disease biology, mode of drug action, and interlinked mechanistic pathways at a molecular level is required.
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Affiliation(s)
- Sabiya Samim Khan
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER) Raebareli, Lucknow (UP) India
| | - Gopal L. Khatik
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER) Raebareli, Lucknow (UP) India
| | - Ashok K. Datusalia
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER) Raebareli, Lucknow (UP) India
- Department of Regulatory Toxicology, National Institute of Pharmaceutical Education and Research (NIPER) Raebareli, Lucknow (UP) India
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2
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Rivi V, Benatti C, Colliva C, Radighieri G, Brunello N, Tascedda F, Blom JMC. Lymnaea stagnalis as model for translational neuroscience research: From pond to bench. Neurosci Biobehav Rev 2019; 108:602-616. [PMID: 31786320 DOI: 10.1016/j.neubiorev.2019.11.020] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 09/24/2019] [Accepted: 11/25/2019] [Indexed: 12/18/2022]
Abstract
The purpose of this review is to illustrate how a reductionistic, but sophisticated, approach based on the use of a simple model system such as the pond snail Lymnaea stagnalis (L. stagnalis), might be useful to address fundamental questions in learning and memory. L. stagnalis, as a model, provides an interesting platform to investigate the dialog between the synapse and the nucleus and vice versa during memory and learning. More importantly, the "molecular actors" of the memory dialogue are well-conserved both across phylogenetic groups and learning paradigms, involving single- or multi-trials, aversion or reward, operant or classical conditioning. At the same time, this model could help to study how, where and when the memory dialog is impaired in stressful conditions and during aging and neurodegeneration in humans and thus offers new insights and targets in order to develop innovative therapies and technology for the treatment of a range of neurological and neurodegenerative disorders.
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Affiliation(s)
- V Rivi
- Dept. of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - C Benatti
- Dept. of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy; Centre of Neuroscience and Neurotechnology, University of Modena and Reggio Emilia, Modena, Italy
| | - C Colliva
- Dept. of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy; Centre of Neuroscience and Neurotechnology, University of Modena and Reggio Emilia, Modena, Italy
| | - G Radighieri
- Dept. of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - N Brunello
- Dept. of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - F Tascedda
- Dept. of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy; Centre of Neuroscience and Neurotechnology, University of Modena and Reggio Emilia, Modena, Italy
| | - J M C Blom
- Dept. of Education and Human Sciences, University of Modena and Reggio Emilia, Modena, Italy; Centre of Neuroscience and Neurotechnology, University of Modena and Reggio Emilia, Modena, Italy.
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3
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Kim HJ. Regulation of Neural Stem Cell Fate by Natural Products. Biomol Ther (Seoul) 2019; 27:15-24. [PMID: 30481958 PMCID: PMC6319553 DOI: 10.4062/biomolther.2018.184] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 10/22/2018] [Accepted: 11/02/2018] [Indexed: 12/13/2022] Open
Abstract
Neural stem cells (NSCs) can proliferate and differentiate into multiple cell types that constitute the nervous system. NSCs can be derived from developing fetuses, embryonic stem cells, or induced pluripotent stem cells. NSCs provide a good platform to screen drugs for neurodegenerative diseases and also have potential applications in regenerative medicine. Natural products have long been used as compounds to develop new drugs. In this review, natural products that control NSC fate and induce their differentiation into neurons or glia are discussed. These phytochemicals enable promising advances to be made in the treatment of neurodegenerative diseases.
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Affiliation(s)
- Hyun-Jung Kim
- Laboratory of Molecular Stem Cell Pharmacology, College of Pharmacy, Chung-Ang University, Seoul 06974,
Republic of Korea
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4
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Safaeinejad F, Bahrami S, Redl H, Niknejad H. Inhibition of Inflammation, Suppression of Matrix Metalloproteinases, Induction of Neurogenesis, and Antioxidant Property Make Bryostatin-1 a Therapeutic Choice for Multiple Sclerosis. Front Pharmacol 2018; 9:625. [PMID: 29971003 PMCID: PMC6018466 DOI: 10.3389/fphar.2018.00625] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Accepted: 05/24/2018] [Indexed: 11/13/2022] Open
Abstract
Multiple sclerosis (MS) is a neurodegenerative disease characterized by inflammation and myelin damage. Pro-inflammatory cytokines, oxidative stress, high level of matrix metalloproteinases (MMPs) activity and blood-brain barrier (BBB) damage, immune-mediated destruction of myelin and neuron loss are involved in the pathogenesis of MS. The currently approved treatments for MS include injectable drugs (interferon-β and glatiramer acetate), oral drugs (fingolimod), and monoclonal antibodies (natalizumab). The mentioned therapeutic choices are mostly focused on the inhibition of inflammation. Therefore, the search for a multi-target therapeutic choice remains unchallenged. It seems that a drug with anti-inflammatory, oxidative stress inhibitory, reduction of MMPs activity, and neurogenesis stimulatory properties may be effective for treatment of MS. In this regard, Bryostatin-1 as a macrolide and marine natural product has been selected as a therapeutic choice. Studies indicate that Bryostatin-1 has anti-inflammatory and antioxidant properties and decreases MMPs level and BBB damage. Furthermore, Bryostatin-1 has a neuroprotective effect and promotes neurogenesis and differentiation of oligodendrocyte progenitor stem cells as a critical step for remyelination/myelogenesis. Based on these properties, we hypothesized here that Bryostatin-1 is an effective treatment in MS.
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Affiliation(s)
- Fahimeh Safaeinejad
- Department of Pharmacology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Soheyl Bahrami
- Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, AUVA Research Centre, Vienna, Austria
| | - Heinz Redl
- Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, AUVA Research Centre, Vienna, Austria
| | - Hassan Niknejad
- Department of Pharmacology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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5
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Salim EI, Harras SF, Abdalla AG, Mona MH. Syphacia muris infection in rats attenuates colorectal carcinogenesis through oxidative stress and gene expression alterations. Implications for modulatory effects by Bryostatin-1. Acta Parasitol 2018; 63:198-209. [PMID: 29351079 DOI: 10.1515/ap-2018-0023] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 11/30/2017] [Indexed: 12/13/2022]
Abstract
Accumulating evidence suggest that some infectious agents may interfere in the natural progression of neoplasia. This study examined the association between chronic infection with adult Syphacia muris parasites and 1,2-dimethylhydrazine (DMH)-induced colorectal carcinogenesis in rats. In addition, the conceivable therapeutic effect of Bryostatin-1, a potent extract of the marine Bryozoan, Bugulane ritina, was investigated against this combined effect.DMH administration has induced aberrant crypt foci (ACF), surrogate biomarkers for colorectal carcinogenesis, while the S. muris infection combined with DMH has significantly increased the total numbers of ACF. Nonetheless, treatment with Bryostatin-1 after infection has significantly reduced the ACF numbers particularly larger ones. This inhibition was concomitant with significant inhibition in the immunohistochemical levels of the ki67, Caspase-3 and IgM levels in colorectal epithelium, as well as serum levels of IgM and IgG. Additionally, treatment with Bryostatin-1 after S. muris + DMH has modulated enzymatic antioxidative markers levels of superoxide dismutase and catalase as well as the non-enzymatic antioxidant markers levels of reduced glutathione, lipid peroxidation, nitric oxide and total antioxidant capacity. Further, treatment with Bryostatin-1 has down-regulated the mRNA expression levels of COX-2 and APC genes in colorectal mucosa. In conclusion, infection with S. muris during colorectal carcinogenesis has significantly modulated the oxidative stress markers in the colorectum, while treatment with Bryostatin-1 has exerted significant curative potential. A mechanism could be explained that Bryostatin-1 treatment has reduced oxidative stress markers activities along with affecting host to parasite immunity possibly leading to changes in the COX-2 and APC expression, retarding cellular proliferation and subsequently reducing the colorectal carcinogenesis events.
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Affiliation(s)
- Elsayed I Salim
- Zoology Department, Faculty of Science, Tanta University, Tanta, 31527, Egypt
| | - Samar F Harras
- Zoology Department, Faculty of Science, Tanta University, Tanta, 31527, Egypt
| | - Aisha G Abdalla
- Zoology Department, Faculty of Science, Tanta University, Tanta, 31527, Egypt
| | - Mohmmed H Mona
- Zoology Department, Faculty of Science, Tanta University, Tanta, 31527, Egypt
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6
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Sun MK, Hongpaisan J, Alkon DL. Rescue of Synaptic Phenotypes and Spatial Memory in Young Fragile X Mice. ACTA ACUST UNITED AC 2016; 357:300-10. [PMID: 26941170 DOI: 10.1124/jpet.115.231100] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 03/02/2016] [Indexed: 01/01/2023]
Abstract
Fragile X syndrome (FXS) is characterized by synaptic immaturity, cognitive impairment, and behavioral changes. The disorder is caused by transcriptional shutdown in neurons of thefragile X mental retardation 1gene product, fragile X mental retardation protein. Fragile X mental retardation protein is a repressor of dendritic mRNA translation and its silencing leads to dysregulation of synaptically driven protein synthesis and impairments of intellect, cognition, and behavior, and FXS is a disorder that currently has no effective therapeutics. Here, young fragile X mice were treated with chronic bryostatin-1, a relatively selective protein kinase Cεactivator, which induces synaptogenesis and synaptic maturation/repair. Chronic treatment with bryostatin-1 rescues young fragile X mice from the disorder phenotypes, including normalization of most FXS abnormalities in 1) hippocampal brain-derived neurotrophic factor expression, 2) postsynaptic density-95 levels, 3) transformation of immature dendritic spines to mature synapses, 4) densities of the presynaptic and postsynaptic membranes, and 5) spatial learning and memory. The therapeutic effects were achieved without downregulation of metabotropic glutamate receptor (mGluR) 5 in the hippocampus and are more dramatic than those of a late-onset treatment in adult fragile X mice. mGluR5 expression was in fact lower in fragile X mice and its expression was restored with the bryostatin-1 treatment. Our results show that synaptic and cognitive function of young FXS mice can be normalized through pharmacological treatment without downregulation of mGluR5 and that bryostatin-1-like agents may represent a novel class of drugs to treat fragile X mental retardation at a young age and in adults.
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Affiliation(s)
- Miao-Kun Sun
- Blanchette Rockefeller Neurosciences Institute, Morgantown, West Virginia
| | - Jarin Hongpaisan
- Blanchette Rockefeller Neurosciences Institute, Morgantown, West Virginia
| | - Daniel L Alkon
- Blanchette Rockefeller Neurosciences Institute, Morgantown, West Virginia
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7
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Larsen EM, Wilson MR, Taylor RE. Conformation-activity relationships of polyketide natural products. Nat Prod Rep 2015; 32:1183-206. [PMID: 25974024 PMCID: PMC4443481 DOI: 10.1039/c5np00014a] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Polyketides represent an important class of secondary metabolites that interact with biological targets connected to a variety of disease-associated pathways. Remarkably, nature's assembly lines, polyketide synthases, manufacture these privileged structures through a combinatorial mixture of just a few structural units. This review highlights the role of these structural elements in shaping a polyketide's conformational preferences, the use of computer-based molecular modeling and solution NMR studies in the identification of low-energy conformers, and the importance of conformational analogues in probing the bound conformation. In particular, this review covers several examples wherein conformational analysis complements classic structure-activity relationships in the design of biologically active natural product analogues.
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Affiliation(s)
- Erik M Larsen
- University of Notre Dame, Department of Chemistry & Biochemistry, 250 Nieuwland Science Hall, Notre Dame, Indiana, USA.
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8
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Kraft M, Poudel YB, Kedei N, Lewin N, Peach ML, Blumberg PM, Keck GE. Synthesis of a des-B-ring bryostatin analogue leads to an unexpected ring expansion of the bryolactone core. J Am Chem Soc 2014; 136:13202-8. [PMID: 25207434 PMCID: PMC4183620 DOI: 10.1021/ja5078188] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Indexed: 11/28/2022]
Abstract
A convergent synthesis of a des-B-ring bryostatin analogue is described. This analogue was found to undergo an unexpected ring expansion of the bryolactone core to generate the corresponding 21-membered macrocycle. The parent analogue and the ring-expanded product both displayed nanomolar binding affinity for PKC. Despite containing A-ring substitution identical to that of bryostatin 1 and displaying bryostatin-like biological function, the des-B-ring analogues displayed a phorbol-like biological function in cells. These studies shed new light on the role of the bryostatin B-ring in conferring bryo-like biological function to bryostatin analogues.
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Affiliation(s)
- Matthew
B. Kraft
- Department
of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Yam B. Poudel
- Department
of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Noemi Kedei
- Laboratory
of Cancer Biology and Genetics, National
Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-4255, United States
| | - Nancy
E. Lewin
- Laboratory
of Cancer Biology and Genetics, National
Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-4255, United States
| | - Megan L. Peach
- Basic Science Program,
Leidos Biomedical Research, Inc., Chemical Biology Laboratory, Frederick National Laboratory for Cancer Research, Frederick, Maryland 21702, United States
| | - Peter M. Blumberg
- Laboratory
of Cancer Biology and Genetics, National
Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-4255, United States
| | - Gary E. Keck
- Department
of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
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9
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Takigami S, Sunada H, Lukowiak K, Kuzirian AM, Alkon DL, Sakakibara M. Protein kinase C mediates memory consolidation of taste avoidance conditioning in Lymnaea stagnalis. Neurobiol Learn Mem 2014; 111:9-18. [PMID: 24613854 DOI: 10.1016/j.nlm.2014.02.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Revised: 02/05/2014] [Accepted: 02/23/2014] [Indexed: 11/25/2022]
Abstract
In Lymnaea stagnalis, in order to obtain a 10 min short-term memory (STM) of taste avoidance conditioning (TAC) at least 10 paired presentations of a conditioned stimulus (CS), sucrose, and an unconditioned stimulus (US), tactile stimulation to the animal's head, are required. Pre-exposure of snails to the protein kinase C (PKC) α and ε activator bryostatin (Bryo) facilitated STM formation in that only 5 paired CS-US trials were required. Typically 20 paired presentations of the CS-US are required for formation of STM and LTM. However, 20 paired presentations do not result in STM or LTM if snails are pre-incubated with a PKC inhibitor, Ro-32-0432. We also found that LTM lasting longer than 48 h was acquired with Bryo incubation for 45 min even after termination of the conditioning paradigm. These data suggest that activation of the α and ε isozymes of PKC is crucially involved in the formation of LTM and provide further support for a mechanism that has been conserved across the evolution of species ranging from invertebrate molluscs to higher mammals.
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Affiliation(s)
- Satoshi Takigami
- Graduate School of Bioscience, Tokai University, 410-0321 Numazu, Shizuoka, Japan
| | - Hiroshi Sunada
- Hotchkiss Brain Institute, University of Calgary, Faculty of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Ken Lukowiak
- Hotchkiss Brain Institute, University of Calgary, Faculty of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Alan M Kuzirian
- Program in Sensory Physiology & Behavior, Marine Biological Laboratory, Woods Hole, MA 02543, USA
| | - Daniel L Alkon
- Blanchette Rockefeller Neuroscience Institute, 9601 Medical Center Drive, Rockville, MD 20850-3332, USA
| | - Manabu Sakakibara
- Graduate School of Bioscience, Tokai University, 410-0321 Numazu, Shizuoka, Japan; School of High-Technology for Human Welfare, Tokai University, 410-0321 Numazu, Shizuoka, Japan.
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10
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Takigami S, Sunada H, Lukowiak K, Sakakibara M. Spaced taste avoidance conditioning in Lymnaea. Neurobiol Learn Mem 2014; 107:79-86. [DOI: 10.1016/j.nlm.2013.10.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 10/31/2013] [Accepted: 10/31/2013] [Indexed: 12/11/2022]
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11
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Kedei N, Lewin NE, Géczy T, Selezneva J, Braun DC, Chen J, Herrmann MA, Heldman MR, Lim L, Mannan P, Garfield SH, Poudel YB, Cummins TJ, Rudra A, Blumberg PM, Keck GE. Biological profile of the less lipophilic and synthetically more accessible bryostatin 7 closely resembles that of bryostatin 1. ACS Chem Biol 2013; 8:767-77. [PMID: 23369356 DOI: 10.1021/cb300671s] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The bryostatins are a group of 20 macrolides isolated by Pettit and co-workers from the marine organism Bugula neritina. Bryostatin 1, the flagship member of the family, has been the subject of intense chemical and biological investigations due to its remarkably diverse biological activities, including promising indications as therapy for cancer, Alzheimer's disease, and HIV. Other bryostatins, however, have attracted far less attention, most probably due to their relatively low natural abundance and associated scarcity of supply. Among all macrolides in this family, bryostatin 7 is biologically the most potent protein kinase C (PKC) ligand (in terms of binding affinity) and also the first bryostatin to be synthesized in the laboratory. Nonetheless, almost no biological studies have been carried out on this agent. We describe herein the total synthesis of bryostatin 7 based on our pyran annulation technology, which allows for the first detailed biological characterizations of bryostatin 7 with side-by-side comparisons to bryostatin 1. The results suggest that the more easily synthesized and less lipophilic bryostatin 7 may be an effective surrogate for bryostatin 1.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | - Yam B. Poudel
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt
Lake City, Utah 84112, United States
| | - Thomas J. Cummins
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt
Lake City, Utah 84112, United States
| | - Arnab Rudra
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt
Lake City, Utah 84112, United States
| | | | - Gary E. Keck
- Department of Chemistry, University of Utah, 315 South 1400 East, RM 2020, Salt
Lake City, Utah 84112, United States
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12
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Sun MK, Alkon DL. Activation of protein kinase C isozymes for the treatment of dementias. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2012; 64:273-302. [PMID: 22840750 DOI: 10.1016/b978-0-12-394816-8.00008-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Memories are much more easily impaired than improved. Dementias, a lasting impairment of memory function, occur in a variety of cognitive disorders and become more clinically dominant as the population ages. Protein kinase C is one of the "cognitive kinases," and plays an essential role in both memory acquisition and maintenance. Deficits in protein kinase C (PKC) signal cascades in neurons represent one of the earliest changes in the brains of patients with Alzheimer's disease (AD) and other types of memory impairment, including those related to cerebral ischemia and ischemic stroke. Inhibition or impairment of PKC activity results in compromised learning and memory, whereas an appropriate activation of certain PKC isozymes leads to an enhancement of learning and memory and/or antidementic effects. In preclinical studies, PKC activators have been shown to increase the expression and activity of PKC isozymes, thereby restoring PKC signaling and downstream activity, including stimulation of neurotrophic activity, synaptic/structural remodeling, and synaptogenesis in the hippocampus and related cortical areas. PKC activators also reduce the accumulation of neurotoxic amyloid and tau protein hyperphosphorylation and support anti-apoptotic processes in the brain. These observations strongly suggest that PKC pharmacology may represent an attractive area for the development of effective cognition-enhancing therapeutics for the treatment of dementias.
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Affiliation(s)
- Miao-Kun Sun
- Blanchette Rockefeller Neurosciences Institute, Morgantown, WV, USA
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13
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Trindade-Silva AE, Lim-Fong GE, Sharp KH, Haygood MG. Bryostatins: biological context and biotechnological prospects. Curr Opin Biotechnol 2011; 21:834-42. [PMID: 20971628 DOI: 10.1016/j.copbio.2010.09.018] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2010] [Revised: 09/25/2010] [Accepted: 09/29/2010] [Indexed: 11/18/2022]
Abstract
Bryostatins are a family of protein kinase C modulators that have potential applications in biomedicine. Found in miniscule quantities in a small marine invertebrate, lack of supply has hampered their development. In recent years, bryostatins have been shown to have potent bioactivity in the central nervous system, an uncultivated marine bacterial symbiont has been shown to be the likely natural source of the bryostatins, the bryostatin biosynthetic genes have been identified and characterized, and bryostatin analogues with promising biological activity have been developed and tested. Challenges in the development of bryostatins for biomedical and biotechnological application include the cultivation of the bacterial symbiont and heterologous expression of bryostatin biosynthesis genes. Continued exploration of the biology as well as the symbiotic origin of the bryostatins presents promising opportunities for discovery of additional bryostatins, and new functions for bryostatins.
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Affiliation(s)
- Amaro E Trindade-Silva
- Instituto de Química de São Carlos, Universidade de São Paulo CP 780, CEP 13560-970, São Carlos, SP, Brazil
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14
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Hale KJ, Manaviazar S. New approaches to the total synthesis of the bryostatin antitumor macrolides. Chem Asian J 2010; 5:704-54. [PMID: 20354984 DOI: 10.1002/asia.200900634] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
In this Focus Review, we give an overview of various bryostatin total syntheses. We also discuss the synthesis of various bryostatin analogues and their biological activity. Work reviewed includes that of Masamune, Evans, Nishiyama and Yamamura, Hale and Manaviazar, Trost, Wender, Keck, Burke, Thomas, and Krische. Our coverage is primarily for the period 2001-2009, since detailed reviews already exist on bryostatin total synthesis work and biology up to this time.
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Affiliation(s)
- Karl J Hale
- School of Chemistry & Chemical Engineering, Queen's Universty Belfast, Stranmillis Road, Belfast BT9 5AG, Northern Ireland, UK.
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15
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Sun MK, Alkon DL. Protein kinase C activators as synaptogenic and memory therapeutics. Arch Pharm (Weinheim) 2010; 342:689-98. [PMID: 19899099 DOI: 10.1002/ardp.200900050] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The last decade has witnessed a rapid progress in understanding of the molecular cascades that may underlie memory and memory disorders. Among the critical players, activity of protein kinase C (PKC) isoforms is essential for many types of learning and memory and their dysfunction, and is critical in memory disorders. PKC inhibition and functional deficits lead to an impairment of various types of learning and memory, consistent with the observations that neurotoxic amyloid inhibits PKC activity and that transgenic animal models with PKCbeta deficit exhibit impaired capacity in cognition. In addition, PKC isozymes play a regulatory role in amyloid production and accumulation. Restoration of the impaired PKC signal pathway pharmacologically results in an enhanced memory capacity and synaptic remodeling / repair and synaptogenesis, and, therefore, represents a potentially important strategy for the treatment of memory disorders, including Alzheimer's dementia. The PKC activators, especially those that are isozyme-specific, are a new class of drug candidates that may be developed as future memory therapeutics.
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Affiliation(s)
- Miao-Kun Sun
- Blanchette Rockefeller Neurosciences Institute, Rockville, MD 20850, USA.
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16
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Abstract
Driven by remarkable advances in the understanding of structure and reaction mechanisms, organic synthesis will be increasingly directed to producing bioinspired and newly designed molecules.
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Affiliation(s)
- Paul A. Wender
- Chemistry Department and, by courtesy, the Department of Chemical and Systems Biology, Stanford University, 333 Campus Drive, Stanford, California 94305-5080, USA
| | - Benjamin L. Miller
- School of Medicine and Dentistry, University of Rochester, 601 Elmwood Avenue, Box 697, Rochester, New York 14642, USA
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