RESUMO
Aliphatic esters are essential constituents of biologically active compounds and versatile chemical intermediates for the synthesis of drugs. However, their preparation from readily available olefins remains challenging. Here, we report a strategy to access aliphatic esters from olefins through a photocatalyzed alkoxycarbonylation reaction. Alkyloxalyl chlorides, generated in situ from the corresponding alcohols and oxalyl chloride, are engaged as alkoxycarbonyl radical fragments under photoredox catalysis. This transformation tolerates a broad scope of electron-rich and electron-deficient olefins and provides the corresponding ß-chloro esters in good yields. Additionally, a formal ß-selective alkene alkoxycarbonylation is developed. Moreover, a variety of oxindole-3-acetates and furoindolines are prepared in good to excellent yields. A more concise formal synthesis of (±)-physovenine is accomplished as well. With these strategies, a wide range of natural-product-derived olefins and alkyloxalyl chlorides are also successfully employed.
Assuntos
Alcenos/química , Técnicas de Química Sintética , Ésteres/química , Indóis/síntese química , Oxindóis/síntese química , Álcoois/química , Catálise , Cloretos/química , Humanos , Estrutura Molecular , Oxalatos/química , Oxirredução , Processos Fotoquímicos , Fisostigmina/análogos & derivados , Fisostigmina/síntese química , EstereoisomerismoRESUMO
The alkaloid physostigmine is an approved anticholinergic drug and an important lead structure for the development of novel therapeutics. Using a complementary approach that merged chemical synthesis with pathway refactoring, we produced a series of physostigmine analogues with altered specificity and toxicity profiles in the heterologous host Myxococcus xanthus. The compounds that were generated by applying a simple feeding strategy include the promising drug candidate phenserine, which was previously accessible only by total synthesis.
Assuntos
Myxococcus xanthus/química , Fisostigmina/análogos & derivados , Fisostigmina/química , Estrutura Molecular , Myxococcus xanthus/metabolismo , Fisostigmina/metabolismoRESUMO
Bitter taste receptors (T2Rs) are GPCRs involved in detection of bitter compounds by type 2 taste cells of the tongue, but are also expressed in other tissues throughout the body, including the airways, gastrointestinal tract, and brain. These T2Rs can be activated by several bacterial products and regulate innate immune responses in several cell types. Expression of T2Rs has been demonstrated in immune cells like neutrophils; however, the molecular details of their signaling are unknown. We examined mechanisms of T2R signaling in primary human monocyte-derived unprimed (M0) macrophages (M[Formula: see text]s) using live cell imaging techniques. Known bitter compounds and bacterial T2R agonists activated low-level calcium signals through a pertussis toxin (PTX)-sensitive, phospholipase C-dependent, and inositol trisphosphate receptor-dependent calcium release pathway. These calcium signals activated low-level nitric oxide (NO) production via endothelial and neuronal NO synthase (NOS) isoforms. NO production increased cellular cGMP and enhanced acute phagocytosis ~ threefold over 30-60 min via protein kinase G. In parallel with calcium elevation, T2R activation lowered cAMP, also through a PTX-sensitive pathway. The cAMP decrease also contributed to enhanced phagocytosis. Moreover, a co-culture model with airway epithelial cells demonstrated that NO produced by epithelial cells can also acutely enhance M[Formula: see text] phagocytosis. Together, these data define M[Formula: see text] T2R signal transduction and support an immune recognition role for T2Rs in M[Formula: see text] cell physiology.
Assuntos
Cálcio/metabolismo , GMP Cíclico/metabolismo , Óxido Nítrico/metabolismo , Fagocitose , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais , Comunicação Celular , Células Cultivadas , Técnicas de Cocultura , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Humanos , Macrófagos/citologia , Macrófagos/imunologia , Macrófagos/metabolismo , Monócitos/citologia , Monócitos/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Toxina Pertussis/farmacologia , Fagocitose/efeitos dos fármacos , Fisostigmina/análogos & derivados , Fisostigmina/farmacologia , Quinolonas/farmacologia , Receptores Acoplados a Proteínas G/agonistas , Transdução de Sinais/efeitos dos fármacosRESUMO
OBJECTIVE: Recent clinical trials targeting amyloid beta (Aß) and tau in Alzheimer's disease (AD) have yet to demonstrate efficacy. Reviewing the hypotheses for AD pathogenesis and defining possible links between them may enhance insights into both upstream initiating events and downstream mechanisms, thereby promoting discovery of novel treatments. Evidence that in Down syndrome (DS), a population markedly predisposed to develop early onset AD, increased APP gene dose is necessary for both AD neuropathology and dementia points to normalization of the levels of the amyloid precursor protein (APP) and its products as a route to further define AD pathogenesis and discovering novel treatments. BACKGROUND: AD and DS share several characteristic manifestations. DS is caused by trisomy of whole or part of chromosome 21; this chromosome contains about 233 protein-coding genes, including APP. Recent evidence points to a defining role for increased expression of the gene for APP and for its 99 amino acid C-terminal fragment (C99, also known as ß-CTF) in dysregulating the endosomal/lysosomal system. The latter is critical for normal cellular function and in neurons for transmitting neurotrophic signals. NEW/UPDATED HYPOTHESIS: We hypothesize that the increase in APP gene dose in DS initiates a process in which increased levels of full-length APP (fl-APP) and its products, including ß-CTF and possibly Aß peptides (Aß42 and Aß40), drive AD pathogenesis through an endosome-dependent mechanism(s), which compromises transport of neurotrophic signals. To test this hypothesis, we carried out studies in the Ts65Dn mouse model of DS and examined the effects of Posiphen, an orally available small molecule shown in prior studies to reduce fl-APP. In vitro, Posiphen lowered fl-APP and its C-terminal fragments, reversed Rab5 hyperactivation and early endosome enlargement, and restored retrograde transport of neurotrophin signaling. In vivo, Posiphen treatment (50 mg/kg/d, 26 days, intraperitoneal [i.p.]) of Ts65Dn mice was well tolerated and demonstrated no adverse effects in behavior. Treatment resulted in normalization of the levels of fl-APP, C-terminal fragments and small reductions in Aß species, restoration to normal levels of Rab5 activity, reduced phosphorylated tau (p-tau), and reversed deficits in TrkB (tropomyosin receptor kinase B) activation and in the Akt (protein kinase B [PKB]), ERK (extracellular signal-regulated kinase), and CREB (cAMP response element-binding protein) signaling pathways. Remarkably, Posiphen treatment also restored the level of choline acetyltransferase protein to 2N levels. These findings support the APP gene dose hypothesis, point to the need for additional studies to explore the mechanisms by which increased APP gene expression acts to increase the risk for AD in DS, and to possible utility of treatments to normalize the levels of APP and its products for preventing AD in those with DS. MAJOR CHALLENGES FOR THE HYPOTHESIS: Important unanswered questions are: (1) When should one intervene in those with DS; (2) would an APP-based strategy have untoward consequences on possible adaptive changes induced by chronically increased APP gene dose; (3) do other genes present on chromosome 21, or on other chromosomes whose expression is dysregulated in DS, contribute to AD pathogenesis; and (4) can one model strategies that combine the use of an APP-based treatment with those directed at other AD phenotypes including p-tau and inflammation. LINKAGE TO OTHER MAJOR THEORIES: The APP gene dose hypothesis interfaces with the amyloid cascade hypothesis of AD as well as with the genetic and cell biological observations that support it. Moreover, upregulation of fl-APP protein and products may drive downstream events that dysregulate tau homeostasis and inflammatory responses that contribute to propagation of AD pathogenesis.
Assuntos
Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Inibidores da Colinesterase/administração & dosagem , Síndrome de Down/genética , Endossomos , Fenótipo , Fisostigmina/análogos & derivados , Doença de Alzheimer/fisiopatologia , Precursor de Proteína beta-Amiloide/genética , Animais , Modelos Animais de Doenças , Síndrome de Down/metabolismo , Endossomos/metabolismo , Endossomos/patologia , Humanos , Camundongos , Neurônios/metabolismo , Fosforilação , Fisostigmina/administração & dosagemRESUMO
AIM: Traumatic brain injury (TBI) is one of the most common causes of morbidity and mortality of both young adults and the elderly, and is a key contributing factor in about 30% of all injury-associated deaths occurring within the United States of America. Albeit substantial impact has been made to improve our comprehension of the mechanisms that underpin the primary and secondary injury stages initiated by a TBI incident, this knowledge has yet to successfully translate into the development of an effective TBI pharmacological treatment. Developing consent suggests that a TBI can concomitantly trigger multiple TBI-linked cascades that then progress in parallel and, if correct, the multifactorial nature of TBI would make the discovery of a single effective mechanism-targeted drug unlikely. DISCUSSION: We review recent data indicating that the small molecular weight drug (-)-phenserine tartrate (PhenT), originally developed for Alzheimer's disease (AD), effectively inhibits a broad range of mechanisms pertinent to mild (m) and moderate (mod)TBI, which in combination underpin the ensuing cognitive and motor impairments. In cellular and animal models at clinically translatable doses, PhenT mitigated mTBI- and modTBI-induced programmed neuronal cell death (PNCD), oxidative stress, glutamate excitotoxicity, neuroinflammation, and effectively reversed injury-induced gene pathways leading to chronic neurodegeneration. In addition to proving efficacious in well-characterized animal TBI models, significantly mitigating cognitive and motor impairments, the drug also has demonstrated neuroprotective actions against ischemic stroke and the organophosphorus nerve agent and chemical weapon, soman. CONCLUSION: In the light of its tolerability in AD clinical trials, PhenT is an agent that can be fast-tracked for evaluation in not only civilian TBI, but also as a potentially protective agent in battlefield conditions where TBI and chemical weapon exposure are increasingly jointly occurring.
Assuntos
Lesões Encefálicas Traumáticas/tratamento farmacológico , Fármacos Neuroprotetores/administração & dosagem , Fisostigmina/análogos & derivados , Tartaratos/administração & dosagem , Animais , Lesões Encefálicas Traumáticas/diagnóstico , Lesões Encefálicas Traumáticas/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Humanos , Camundongos , Camundongos Transgênicos , Fármacos Neuroprotetores/química , Fisostigmina/administração & dosagem , Fisostigmina/química , Tartaratos/química , Resultado do TratamentoRESUMO
Aim: Alzheimer's disease (AD) is known to be themajor cause of dementia among the elderly. The structural properties and binding interactions of the AD drug physostigmine (-)-phy, and its analogues (-)-hex and (-)-phe and (+)-phe, were examined, as well as their impact on the conformational changes of two different AD target enzymes AChE and BChE. Materials & methods: The conformational changes were studied using molecular dynamics and structural properties using Quantum mechanics. Results & conclusions: The binding free energy (ΔGbind) and the change in the free energy surface (FES) computed from the funnel metadynamics (FMD) simulation, both support the idea that inhibitors (-)-phe and (-)-hex have better binding activities toward enzyme AChE, and that (-)-phe is stronger in binding than the present AD drug (-)-phy.
Assuntos
Acetilcolinesterase/química , Butirilcolinesterase/química , Inibidores da Colinesterase/química , Fisostigmina/análogos & derivados , Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Sítios de Ligação , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/metabolismo , Inibidores da Colinesterase/uso terapêutico , Análise por Conglomerados , Humanos , Ligantes , Simulação de Dinâmica Molecular , Fisostigmina/metabolismo , Fisostigmina/uso terapêutico , Análise de Componente Principal , Ligação Proteica , Teoria Quântica , TermodinâmicaRESUMO
BACKGROUND: In the context of the cholinergic anti-inflammatory pathway, the clinical trial Anticholium® per Se (EudraCT Number: 2012-001650-26, ClinicalTrials.gov NCT03013322) addressed the possibility of taking adjunctive physostigmine salicylate treatment in septic shock from bench to bedside. Pharmacokinetics (PK) are likely altered in critically ill patients; data on physostigmine PK and target concentrations are sparse, particularly for continuous infusion. Our objective was to build a population PK (popPK) model for physostigmine, and further evaluate pharmacodynamics (PD) and concentration-response relationship in this setting. METHODS: In the randomized, double-blind, placebo-controlled trial, 20 patients with perioperative septic shock either received an initial dose of 0.04â¯mg/kg physostigmine salicylate, followed by continuous infusion of 1â¯mg/h for up to 120â¯h, or equivalent volumes of 0.9% sodium chloride (placebo group). Physostigmine plasma concentrations and acetylcholinesterase (AChE) activity were measured; concentration-response associations were evaluated, and popPK and PD modeling was performed with NONMEM. RESULTS: Steady state physostigmine plasma concentrations reached 7.60⯱â¯2.81â¯ng/mL (mean⯱â¯standard deviation [SD]). PK was best described by a two-compartment model with linear clearance. Significant covariate effects were detected for body weight and age on clearance, as well as a high inter-individual variability of the central volume of distribution. AChE activity was significantly reduced to 30.5%-50.6% of baseline activity during physostigmine salicylate infusion. A sigmoidal direct effect PD model best described enzyme inhibition by physostigmine, with an estimated half maximal effective concentration (EC50) of 5.99â¯ng/mL. CONCLUSIONS: PK of physostigmine in patients with septic shock displayed substantial inter-individual variability with body weight and age influencing the clearance. Physostigmine inhibited AChE activity with a sigmoidal concentration-response effect.
Assuntos
Modelos Biológicos , Fisostigmina/análogos & derivados , Choque Séptico/tratamento farmacológico , Idoso , Colinesterases/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fisostigmina/administração & dosagem , Fisostigmina/farmacocinética , Fisostigmina/uso terapêutico , Choque Séptico/sangueRESUMO
BACKGROUND: The inhibition of cholinesterase enzymes is one of the promising strategies to manage several neurological disorders that include Alzheimer's disease (AD). MATERIAL AND METHODS: In the current article, we estimated the potential inhibition of acetyl cholinesterase (AChE) by phenserine using slightly modified Ellman assay. To find out the binding interactions of phenserine with the catalytic site of AChE, a molecular docking study was also performed. RESULTS: Phenserine was found to inhibit Electrophorus electricus AChE in a dose-dependent manner with an IC50 value of 0.013 µM. The kinetic analyses indicate that phenserine inhibits AChE in a mixed type manner (competitive and uncompetitive) with Ki values of 0.39 µmole/l and 0.21 µmole/l, respectively. On the other hand, Km and Vmax values were found to be 0.17 µM and 0.39 µM, respectively. The molecular docking studies indicate efficient binding of phenserine through 6 hydrogen bonds, 4 pi-alkyl interactions, and 1 pi-pi interaction within the AChE catalytic pocket. CONCLUSION: Results of our computational and kinetics studies indicated a mixed type inhibition by phenserine at AChE catalytic site.
Assuntos
Acetilcolinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Fisostigmina/análogos & derivados , Animais , Electrophorus , Cinética , Simulação de Acoplamento Molecular , Fisostigmina/farmacologiaRESUMO
Mild traumatic brain injury (mTBI) is a risk factor for neurodegenerative disorders, such as Alzheimer's disease (AD) and Parkinson's disease (PD). TBI-derived neuropathologies are promoted by inflammatory processes: chronic microgliosis and release of pro-inflammatory cytokines that further promote neuronal dysfunction and loss. Herein, we evaluated the effect on pre-programmed cell death/neuroinflammation/synaptic integrity and function of (-)-Phenserine tartrate (Phen), an agent originally developed for AD. This was studied at two clinically translatable doses (2.5 and 5.0â¯mg/kg, BID), in a weight drop (concussive) mTBI model in wild type (WT) and AD APP/PSEN1 transgenic mice. Phen mitigated mTBI-induced cognitive impairment, assessed by Novel Object Recognition and Y-maze behavioral paradigms, in WT mice. Phen fully abated mTBI-induced neurodegeneration, evaluated by counting Fluoro-Jade C-positive (FJC+) cells, in hippocampus and cortex of WT mice. In APP/PSEN1 mice, degenerating cell counts were consistently greater across all experimental groups vs. WT mice. mTBI elevated FJC+ cell counts vs. the APP/PSEN1 control (sham) group, and Phen similarly mitigated this. Anti-inflammatory effects on microglial activation (IBA1-immunoreactivity (IR)) and the pro-inflammatory cytokine TNF-α were evaluated. mTBI increased IBA1-IR and TNF-α/IBA1 colocalization vs. sham, both in WT and APP/PSEN1 mice. Phen decreased IBA1-IR throughout hippocampi and cortices of WT mice, and in cortices of AD mice. Phen, likewise, reduced levels of IBA1/TNF-α-IR colocalization volume across all areas in WT animals, with a similar trend in APP/PSEN1 mice. Actions on astrocyte activation by mTBI were followed by evaluating GFAP, and were similarly mitigated by Phen. Synaptic density was evaluated by quantifying PSD-95+ dendritic spines and Synaptophysin (Syn)-IR. Both were significantly reduced in mTBI vs. sham in both WT and APP/PSEN1 mice. Phen fully reversed the PSD-95+ spine loss in WT and Syn-IR decrease in both WT and APP/PSEN1 mice. To associate immunohistochemical changes in synaptic markers with function, hippocampal long term potentiation (LTP) was induced in WT mice. LTP was impaired by mTBI, and this impairment was mitigated by Phen. In synopsis, clinically translatable doses of Phen ameliorated mTBI-mediated pre-programmed cell death/neuroinflammation/synaptic dysfunction in WT mice, consistent with fully mitigating mTBI-induced cognitive impairments. Phen additionally demonstrated positive actions in the more pathologic brain microenvironment of AD mice, further supporting consideration of its repurposing as a treatment for mTBI.
Assuntos
Doença de Alzheimer/tratamento farmacológico , Concussão Encefálica/tratamento farmacológico , Morte Celular/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Fisostigmina/análogos & derivados , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Concussão Encefálica/metabolismo , Concussão Encefálica/patologia , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Modelos Animais de Doenças , Hipocampo/metabolismo , Hipocampo/patologia , Camundongos , Camundongos Transgênicos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Fisostigmina/farmacologia , Fisostigmina/uso terapêuticoRESUMO
Traumatic brain injury (TBI), a major cause of mortality and morbidity, affects 10 million people worldwide, with limited treatment options. We have previously shown that (-)-phenserine (Phen), an acetylcholinesterase inhibitor originally designed and tested in clinical phase III trials for Alzheimer's disease, can reduce neurodegeneration after TBI and reduce cognitive impairments induced by mild TBI. In this study, we used a mouse model of moderate to severe TBI by controlled cortical impact to assess the effects of Phen on post-trauma histochemical and behavioral changes. Animals were treated with Phen (2.5 mg/kg, IP, BID) for 5 days started on the day of injury and the effects were evaluated by behavioral and histological examinations at 1 and 2 weeks after injury. Phen significantly attenuated TBI-induced contusion volume, enlargement of the lateral ventricle, and behavioral impairments in motor asymmetry, sensorimotor functions, motor coordination, and balance functions. The morphology of microglia was shifted to an active from a resting form after TBI, and Phen dramatically reduced the ratio of activated to resting microglia, suggesting that Phen also mitigates neuroinflammation after TBI. While Phen has potent anti-acetylcholinesterase activity, its (+) isomer Posiphen shares many neuroprotective properties but is almost completely devoid of anti-acetylcholinesterase activity. We evaluated Posiphen at a similar dose to Phen and found similar mitigation in lateral ventricular size increase, motor asymmetry, motor coordination, and balance function, suggesting the improvement of these histological and behavioral tests by Phen treatment occur via pathways other than anti-acetylcholinesterase inhibition. However, the reduction of lesion size and improvement of sensorimotor function by Posiphen were much smaller than with equivalent doses of Phen. Taken together, these results show that post-injury treatment with Phen over 5 days significantly ameliorates severity of TBI. These data suggest a potential development of this compound for clinical use in TBI therapy.
Assuntos
Comportamento Animal/efeitos dos fármacos , Contusão Encefálica , Fármacos Neuroprotetores/farmacologia , Fisostigmina/análogos & derivados , Animais , Contusão Encefálica/tratamento farmacológico , Contusão Encefálica/metabolismo , Contusão Encefálica/patologia , Contusão Encefálica/fisiopatologia , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/patologia , Inflamação/fisiopatologia , Masculino , Camundongos , Microglia/metabolismo , Microglia/patologia , Fisostigmina/farmacologia , Fatores de TempoRESUMO
PURPOSE: The cholinergic anti-inflammatory pathway has been shown to be accessible by physostigmine salicylate in animal models. However, the cholinesterase inhibitor is not approved for adjunctive therapy in sepsis, and tolerability and safety of high initial doses followed by continuous infusion have not been investigated. MATERIALS AND METHODS: In this trial, 20 patients with perioperative septic shock due to intra-abdominal infection were eligible. The physostigmine group received an initial dose of 0.04â¯mg/kg physostigmine salicylate, followed by continuous infusion of 1â¯mg/h for 120â¯h; the placebo group was treated with 0.9% sodium chloride. Primary outcome was the mean Sequential Organ Failure Assessment (SOFA) score during treatment and up to 14â¯days. RESULTS: Administration of physostigmine salicylate was well tolerated. Mean SOFA scores were 8.9⯱â¯2.5 and 11.3⯱â¯3.6 (mean⯱â¯SD) for physostigmine and placebo group, respectively. Adjusted for age, difference between means was not statistically significant (-2.37, 95% CI: -5.43 to 0.70, pâ¯=â¯0.121). Norepinephrine doses required only appeared lower in the physostigmine group (pâ¯=â¯0.064), along with a more rapid reduction from an elevated heart rate possibly indicating less hemodynamic instability. CONCLUSIONS: Treatment with physostigmine salicylate was feasible and safe. Further studies are justified to assess the effect on recovery from septic shock. TRIAL REGISTRATION: EudraCT Number 2012-001650-26, ClinicalTrials.gov identifier NCT03013322.
Assuntos
Infecções Intra-Abdominais/tratamento farmacológico , Fisostigmina/análogos & derivados , Choque Séptico/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cuidados Críticos/métodos , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Norepinefrina/uso terapêutico , Escores de Disfunção Orgânica , Segurança do Paciente , Período Perioperatório , Fisostigmina/administração & dosagem , Projetos Piloto , Sepse/tratamento farmacológico , Cloreto de Sódio/administração & dosagem , Adulto JovemRESUMO
OBJECTIVE: Although cerebral ischemia can activate endogenous reparative processes, such as proliferation of endogenous neural stem cells (NSCs) in the subventricular zone (SVZ) and subgranular zone (SGZ), the majority of these new cells die shortly after injury and do not appropriately differentiate into neurons, or migrate and functionally integrate into the brain. The purpose of this study was to examine a novel strategy for treatment of stroke after injury by optimizing the survival of ischemia-induced endogenous NSCs in the SVZ and SGZ. METHODS: Adult SVZ and SGZ NSCs were grown as neurospheres in culture and treated with a p53 inactivator, pifithrin-α (PFT-α), and an amyloid precursor protein (APP)-lowering drug, posiphen, and effects on neurosphere number, size and neuronal differentiation were evaluated. This combined sequential treatment approach was then evaluated in mice challenged with middle cerebral artery occlusion (MCAo). Locomotor behavior and cognition were evaluated at 4 weeks, and the number of new surviving neurons was quantified in nestin creERT2-YFP mice. RESULTS: PFT-α and posiphen enhanced the self-renewal, proliferation rate and neuronal differentiation of adult SVZ and SGZ NSCs in culture. Their sequential combination in mice challenged with MCAo-induced stroke mitigated locomotor and cognitive impairments and increased the survival of SVZ and SGZ NSCs cells. PFT-α and the combined posiphen+PFT-α treatment similarly improved locomotion behavior in stroke challenged mice. Notably, however, the combined treatment provided significantly more potent cognitive function enhancement in stroke mice, as compared with PFT-α single treatment. INTERPRETATION: Delayed combined sequential treatment with an inhibitor of p53 dependent apoptosis (PFT-α) and APP synthesis (posiphen) proved able to enhance stroke-induced endogenous neurogenesis and improve the functional recovery in stroke animals. Whereas the combined sequential treatment provided no further improvement in locomotor function, as compared with PFT-α alone treatment, suggesting a potential ceiling in the locomotion behavioral outcome in stroke animals, combined treatment more potently augmented cognitive function recovery after stroke.
Assuntos
Benzotiazóis/uso terapêutico , Neurogênese , Fisostigmina/análogos & derivados , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/fisiopatologia , Tolueno/análogos & derivados , Animais , Atrofia , Benzotiazóis/farmacologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Autorrenovação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cognição/efeitos dos fármacos , Quimioterapia Combinada , Ventrículos Laterais/patologia , Ventrículos Laterais/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Proteínas Associadas aos Microtúbulos/metabolismo , Atividade Motora/efeitos dos fármacos , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/metabolismo , Neurogênese/efeitos dos fármacos , Fisostigmina/farmacologia , Fisostigmina/uso terapêutico , Recuperação de Função Fisiológica/efeitos dos fármacos , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/metabolismo , Tolueno/farmacologia , Tolueno/uso terapêuticoRESUMO
BACKGROUND: Concussion (mild) and other moderate traumatic brain injury (TBI) and Alzheimer's disease (AD) share overlapping neuropathologies, including neuronal pre-programmed cell death (PPCD), and clinical impairments and disabilities. Multiple clinical trials targeting mechanisms based on the Amyloid Hypothesis of AD have so far failed, indicating that it is prudent for new drug developments to also pursue mechanisms independent of the Amyloid Hypothesis. To address these issues, we have proposed the use of an animal model of concussion/TBI as a supplement to AD transgenic mice to provide an indication of an AD drug candidate's potential for preventing PPCD and resulting progression towards dementia in AD. METHODS: We searched PubMed/Medline and the references of identified articles for background on the neuropathological progression of AD and its implications for drug target identification, for AD clinical trial criteria used to assess disease modification outcomes, for plasma biomarkers associated with AD and concussion/TBI, neuropathologies and especially PPCD, and for methodological critiques of AD and other neuropsychiatric clinical trial methods. RESULTS: We identified and address seven issues and highlight the Thal-Sano AD 'Time to Onset of Impairment' Design for possible applications in our clinical trials. Diverse and significant pathological cascades and indications of self-induced neuronal PPCD were found in concussion/TBI, anoxia, and AD animal models. To address the dearth of peripheral markers of AD and concussion/TBI brain pathologies and PPCD we evaluated Extracellular Vesicles (EVs) enriched for neuronal origin, including exosomes. In our concussion/TBI, anoxia and AD animal models we found evidence consistent with the presence of time-dependent PPCD and (-)-phenserine suppression of neuronal self-induced PPCD. We hence developed an extended controlled release formulation of (-)-phenserine to provide individualized dosing and stable therapeutic brain concentrations, to pharmacologically interrogate PPCD as a drug development target. To address the identified problems potentially putting any clinical trial at risk of failure, we developed exploratory AD and concussion/TBI clinical trial designs. CONCLUSIONS: Our findings inform the biomarker indication of progression of pathological targets in neurodegenerations and propose a novel approach to these conditions through neuronal protection against self-induced PPCD.
Assuntos
Doença de Alzheimer/tratamento farmacológico , Morte Celular/efeitos dos fármacos , Inibidores da Colinesterase/uso terapêutico , Fisostigmina/análogos & derivados , Animais , Humanos , Fisostigmina/uso terapêuticoRESUMO
Boldine, a bioactive compound, has been reported to be neuroprotective, but its effect on learning and memory has not been explored. So, the present study was aimed to study the effect of boldine on the learning and memory of the Swiss albino male young and aged mice. Boldine (1.5, 3 and 6mg/kg, po) and physostigmine salicylate (0.1mg/kg, ip) were administered to separate groups of mice for 7 successive days. Morris water maze was utilized as a behavioural model to study the effect of drugs on learning and memory of mice. Boldine and physostigmine significantly improved learning and memory of young as well as aged mice, as indicated by decrease in escape latency time during training session and increase in time spent in target quadrant during retrieval session. No significant effect on locomotor activities of mice was observed due to drug treatments. Memory-enhancing activity of boldine (3mg/kg) was found to be comparable to physostigmine. Boldine significantly reversed scopolamine-, sodium nitrite- and aging-induced amnesia in mice. Moreover, boldine attenuated oxidative stress, as shown by a significant decrease in brain malondialdehyde as well as brain nitrite levels and a significant increase in brain GSH level of young as well as aged mice. Brain acetylcholinesterase activity was also significantly inhibited by boldine in young as well as aged mice. In conclusion boldine administered for 7 successive days exhibited significant improvement of learning and memory of young and aged mice possibly through inhibition of brain acetylcholinesterase activity and alleviation of brain oxidative stress.
Assuntos
Aporfinas/farmacologia , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Nootrópicos/farmacologia , Acetilcolinesterase/efeitos dos fármacos , Acetilcolinesterase/metabolismo , Fatores Etários , Amnésia/tratamento farmacológico , Animais , Aporfinas/administração & dosagem , Comportamento Animal , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Inibidores da Colinesterase/administração & dosagem , Inibidores da Colinesterase/farmacologia , Relação Dose-Resposta a Droga , Glutationa/metabolismo , Masculino , Malondialdeído/metabolismo , Camundongos , Nitritos/metabolismo , Nootrópicos/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Fisostigmina/análogos & derivados , Fisostigmina/farmacologiaRESUMO
BACKGROUND: Severe sepsis and septic shock remain a major challenge, even in modern intensive care. In Germany, about 68,000 patients die annually because of septic diseases, characterized by a complex systemic inflammatory response. Causal treatment of the underlying infection is essential for successful management of sepsis, but the course can be positively influenced by supportive and adjuvant measures. The cholinergic anti-inflammatory pathway (CAP) represents a new approach to adjunctive therapy of septic diseases and can be pharmacologically activated by the acetylcholinesterase inhibitor physostigmine (Anticholium®). Promising effects can be found in several in vitro and in vivo models of sepsis, such as a reduction in pro-inflammatory cytokines and improved survival. METHODS: Anticholium® per Se is a randomized, double-blind, placebo-controlled, monocentric trial to assess whether the CAP can be transferred from bench to bedside. In this pilot study, 20 patients with perioperative sepsis and septic shock as a result of intra-abdominal infection are enrolled. According to randomization, participants are treated with physostigmine salicylate (verum group) or 0.9% sodium chloride (placebo group) for up to 5 days. The mean Sequential Organ Failure Assessment (SOFA) score during treatment and subsequent intensive care of up to 14 days is used as surrogate outcome (primary endpoint). Secondary outcome measures include 30- and 90-day mortality. An embedded pharmacokinetics and pharmacodynamics study investigates plasma concentrations of physostigmine and its metabolite eseroline. Further analyses will contribute to our understanding of the role of various cytokines in the pathophysiology of human sepsis. A computer-generated list is used for block randomization. DISCUSSION: This randomized, controlled, monocentric trial investigates for the first time the adjunctive use of physostigmine (Anticholium®) in patients with perioperative sepsis and septic shock and may be a pivotal step toward the clinical use in this indication. TRIAL REGISTRATION: EudraCT Number: 2012-001650-26 (entered 14 August 2012), ClinicalTrials.gov identifier: NCT03013322 (registered on 1 Jan 2017).
Assuntos
Anti-Inflamatórios/uso terapêutico , Inibidores da Colinesterase/uso terapêutico , Fisostigmina/análogos & derivados , Sepse/tratamento farmacológico , Choque Séptico/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Inflamatórios/efeitos adversos , Anti-Inflamatórios/farmacocinética , Inibidores da Colinesterase/efeitos adversos , Inibidores da Colinesterase/farmacocinética , Protocolos Clínicos , Método Duplo-Cego , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Escores de Disfunção Orgânica , Assistência Perioperatória , Fisostigmina/efeitos adversos , Fisostigmina/farmacocinética , Fisostigmina/uso terapêutico , Projetos Piloto , Estudos Prospectivos , Projetos de Pesquisa , Sepse/diagnóstico , Sepse/microbiologia , Sepse/mortalidade , Choque Séptico/diagnóstico , Choque Séptico/microbiologia , Choque Séptico/mortalidade , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
Stroke commonly leads to adult disability and death worldwide. Its major symptoms are spastic hemiplegia and discordant motion, consequent to neuronal cell death induced by brain vessel occlusion. Acetylcholinesterase (AChE) is upregulated and allied with inflammation and apoptosis after stroke. Recent studies suggest that AChE inhibition ameliorates ischemia-reperfusion injury and has neuroprotective properties. (-)-Phenserine, a reversible AChE inhibitor, has a broad range of actions independent of its AChE properties, including neuroprotective ones. However, its protective effects and detailed mechanism of action in the rat middle cerebral artery occlusion model (MCAO) remain to be elucidated. This study investigated the therapeutic effects of (-)-phenserine for stroke in the rat focal cerebral ischemia model and oxygen-glucose deprivation/reperfusion (OGD/RP) damage model in SH-SY5Y neuronal cultures. (-)-Phenserine mitigated OGD/PR-induced SH-SY5Y cell death, providing an inverted U-shaped dose-response relationship between concentration and survival. In MCAO challenged rats, (-)-phenserine reduced infarction volume, cell death and improved body asymmetry, a behavioral measure of stoke impact. In both cellular and animal studies, (-)-phenserine elevated brain-derived neurotrophic factor (BDNF) and B-cell lymphoma 2 (Bcl-2) levels, and decreased activated-caspase 3, amyloid precursor protein (APP) and glial fibrillary acidic protein (GFAP) expression, potentially mediated through the ERK-1/2 signaling pathway. These actions mitigated neuronal apoptosis in the stroke penumbra, and decreased matrix metallopeptidase-9 (MMP-9) expression. In synopsis, (-)-phenserine significantly reduced neuronal damage induced by ischemia/reperfusion injury in a rat model of MCAO and cellular model of OGD/RP, demonstrating that its anti-apoptotic/neuroprotective/neurotrophic cholinergic and non-cholinergic properties warrant further evaluation in conditions of brain injury.
Assuntos
Apoptose/efeitos dos fármacos , Isquemia Encefálica/tratamento farmacológico , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Fisostigmina/análogos & derivados , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Apoptose/fisiologia , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/fisiologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Inibidores da Colinesterase/farmacologia , Relação Dose-Resposta a Droga , Glucose/deficiência , Humanos , Masculino , Neurônios/metabolismo , Neurônios/patologia , Fisostigmina/farmacologia , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/patologiaRESUMO
Traumatic brain injury (TBI) is one of the most common causes of morbidity and mortality of both young adults of less than 45 years of age and the elderly, and contributes to about 30% of all injury deaths in the United States of America. Whereas there has been a significant improvement in our understanding of the mechanism that underpin the primary and secondary stages of damage associated with a TBI incident, to date however, this knowledge has not translated into the development of effective new pharmacological TBI treatment strategies. Prior experimental and clinical studies of drugs working via a single mechanism only may have failed to address the full range of pathologies that lead to the neuronal loss and cognitive impairment evident in TBI and other disorders. The present review focuses on two drugs with the potential to benefit multiple pathways considered important in TBI. Notably, both agents have already been developed into human studies for other conditions, and thus have the potential to be rapidly repositioned as TBI therapies. The first is N-acetyl cysteine (NAC) that is currently used in over the counter medications for its anti-inflammatory properties. The second is (-)-phenserine ((-)-Phen) that was originally developed as an experimental Alzheimer's disease (AD) drug. We briefly review background information about TBI and subsequently review literature suggesting that NAC and (-)-Phen may be useful therapeutic approaches for TBI, for which there are no currently approved drugs.
Assuntos
Acetilcisteína/uso terapêutico , Lesões Encefálicas Traumáticas/tratamento farmacológico , Reposicionamento de Medicamentos , Fisostigmina/análogos & derivados , Psicotrópicos/uso terapêutico , Animais , Anti-Inflamatórios/uso terapêutico , Inibidores da Colinesterase/uso terapêutico , Humanos , Camundongos , Fisostigmina/uso terapêutico , RatosRESUMO
BACKGROUND: Selective butyrylcholinesterase (BuChE)-inhibition, increases acetylcholine (ACh) levels. In rodents, this inhibition is known to boost cognition. Also, this occurs without the typical unwanted adverse effects of acetylcholinesterase-inhibitors or AChE-Is. The novel compound, fluorobenzylcymserine (FBC), is derived from our effort to design a selective BuChE-inhibitor. Also, we wanted to check whether butyrylcholinesterase-inhibitors (BuChE-Is) possessed an edge over AChE-Is in Alzheimer's disease (AD) in terms of efficacy and/or tolerance. METHOD: FBC was synthesized as reported earlier while enzymatic activity of BuChE was calculated by Ellman-technique. Molecular docking was performed using Autodock4.2. We applied classical as well as innovative analyses of enzyme-kinetics for exploring "FBC:human BuChE-interaction". The mode of inhibition and kinetic parameters were also determined. RESULTS: Docking results displayed two strong interacting sites for FBC. One of these binding sites was previously identified as a deep narrow groove having polar aromatic residues while a second site was identified during this study which displayed better interaction and was lined with aliphatic and sulphur containing residues. At low concentrations of BuChE, the IC50 was found to be very low i.e. 4.79 and 6.10 nM for 12 and 36 µg, respectively, whereas it increased exponentially by increasing the units of BuChE. CONCLUSION: These analyses indicate that FBC is an interesting AD drug candidate that could provide a potent and partial mixed type of inhibition of human BuChE.
Assuntos
Doença de Alzheimer/tratamento farmacológico , Butirilcolinesterase/efeitos dos fármacos , Inibidores da Colinesterase/farmacologia , Fisostigmina/análogos & derivados , Sítios de Ligação , Butirilcolinesterase/metabolismo , Humanos , Concentração Inibidora 50 , Cinética , Simulação de Acoplamento Molecular , Fisostigmina/farmacologiaRESUMO
Traumatic brain injury (TBI), often caused by a concussive impact to the head, affects an estimated 1.7 million Americans annually. With no approved drugs, its pharmacological treatment represents a significant and currently unmet medical need. In our prior development of the anti-cholinesterase compound phenserine for the treatment of neurodegenerative disorders, we recognized that it also possesses non-cholinergic actions with clinical potential. Here, we demonstrate neuroprotective actions of phenserine in neuronal cultures challenged with oxidative stress and glutamate excitotoxicity, two insults of relevance to TBI. These actions translated into amelioration of spatial and visual memory impairments in a mouse model of closed head mild TBI (mTBI) two days following cessation of clinically translatable dosing with phenserine (2.5 and 5.0 mg/kg BID x 5 days initiated post mTBI) in the absence of anti-cholinesterase activity. mTBI elevated levels of thiobarbituric acid reactive substances (TBARS), a marker of oxidative stress. Phenserine counteracted this by augmenting homeostatic mechanisms to mitigate oxidative stress, including superoxide dismutase [SOD] 1 and 2, and glutathione peroxidase [GPx], the activity and protein levels of which were measured by specific assays. Microarray analysis of hippocampal gene expression established that large numbers of genes were exclusively regulated by each individual treatment with a substantial number of them co-regulated between groups. Molecular pathways associated with lipid peroxidation were found to be regulated by mTBI, and treatment of mTBI animals with phenserine effectively reversed injury-induced regulations in the 'Blalock Alzheimer's Disease Up' pathway. Together these data suggest that multiple phenserine-associated actions underpin this compound's ability to ameliorate cognitive deficits caused by mTBI, and support the further evaluation of the compound as a therapeutic for TBI.
Assuntos
Concussão Encefálica/tratamento farmacológico , Disfunção Cognitiva/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Fisostigmina/análogos & derivados , Animais , Concussão Encefálica/complicações , Concussão Encefálica/patologia , Colinérgicos/administração & dosagem , Inibidores da Colinesterase/administração & dosagem , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/patologia , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Ácido Glutâmico/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/patologia , Fisostigmina/administração & dosagemRESUMO
The intramolecular 1,5-H transfer reaction of the aryl radicals generated from unactivated aryl iodides by photocatalysis is described. The features of this transformation are operational simplicity, excellent yields, mild reaction conditions, and good functional group tolerance. With this approach, a more concise formal synthesis of (±)-coerulescine and (±)-physovenine is accomplished.