piperidines and Neurodegenerative-Diseases

Heterocycles and their derivatives hold an important place in medicinal chemistry due to their vast therapeutic and pharmacological significance and wider implications in drug design and development. Piperidine is a nitrogen-containing heterocyclic moiety that exhibits an array of pharmacological properties. This review discusses the potential of piperidine derivatives against the neurodegenerative disease Alzheimer's. The incidences of Alzheimer's disease are increasing nowadays, and constant efforts are being made to develop a medicinal agent for this disease. We have highlighted the advancement in developing piperidine-based anti-neuronal disease compounds and the profound activities of some major piperidine-bearing drug molecules with their important target site. This review focuses on advancements in the field of natural and synthetic occurring piperidines active against Alzheimer's disease, with emphasis on the past 6 years. The discussion also includes the structure-activity relationship, the structures of the most promising molecules, and their biological activities against Alzheimer's disease. The promising activities revealed by these piperidinebased scaffolds undoubtedly place them at the forefront of discovering prospective drug candidates. Thus, it would be of great interest to researchers working on synthesizing neuroprotective drug candidates.

Topics: Alzheimer Disease; Humans; Neurodegenerative Diseases; Piperidines; Structure-Activity Relationship

Topics: Animals; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Development; Humans; Ligands; Neurodegenerative Diseases; Neuroprotective Agents; Piperidines; Receptors, sigma; Sigma-1 Receptor

Selective GluN2B/N-methyl-D-aspartate receptor (NMDAR) antagonists have exposed their clinical effectiveness in a cluster of neurodegenerative diseases, such as epilepsy, Alzheimer's disease, Parkinson's disease, pain, and depression. Hence, GluN2B/NMDARs are considered to be a prospective target for the management of neurodegenerative diseases. Here, we have discussed the current results and significance of subunit selective GluN2B/NMDAR antagonists to pave the way for the establishment of new, safe, and economical drug candidates in the near future. By using summarized data of selective GluN2B/NMDAR antagonists, medicinal chemists are certainly a step closer to the goal of improving the therapeutic and side effect profile of selective antagonists. Outlined summary of designing strategies, synthetic schemes, and pharmacological evaluation studies reinvigorate efforts to identify, modify, and synthesize novel GluN2B/NMDAR antagonists for treating neurodegenerative diseases.

Topics: Animals; Humans; Neurodegenerative Diseases; Piperidines; Receptors, N-Methyl-D-Aspartate

Fyn is a non-receptor tyrosine kinase belonging to the Src family of kinases (SFKs) which has been implicated in several integral functions throughout the central nervous system (CNS), including myelination and synaptic transmission. More recently, Fyn dysfunction has been associated with pathological processes observed in neurodegenerative diseases, such as multiple sclerosis (MS), Alzheimer's disease (AD) and Parkinson's disease (PD). Neurodegenerative diseases are amongst the leading cause of death and disability worldwide and, due to the ageing population, prevalence is predicted to rise in the coming years. Symptoms across neurodegenerative diseases are both debilitating and degenerative in nature and, concerningly, there are currently no disease-modifying therapies to prevent their progression. As such, it is important to identify potential new therapeutic targets. This review will outline the role of Fyn in normal/homeostatic processes, as well as degenerative/pathological mechanisms associated with neurodegenerative diseases, such as demyelination, pathological protein aggregation, neuroinflammation and cognitive dysfunction.

Topics: Alzheimer Disease; Amyloid beta-Peptides; Benzamides; Central Nervous System; Dasatinib; Humans; Molecular Targeted Therapy; Multiple Sclerosis; Myelin Sheath; Nerve Tissue Proteins; Neurodegenerative Diseases; Oligodendroglia; Parkinson Disease; Piperidines; Proto-Oncogene Proteins c-fyn; PrPC Proteins; Pyridines; Receptors, N-Methyl-D-Aspartate; T-Cell Antigen Receptor Specificity; T-Lymphocyte Subsets; tau Proteins; Thiazoles

Huntington's disease (HD) is a highly common inherited monogenic neurodegenerative disease, and the gene responsible for its development is located in the 4p16.3 chromosome. The product of that gene mutation is an abnormal huntingtin (Htt) protein that disrupts the neural conduction, thus leading to motor and cognitive disorders. The disease progresses to irreversible changes in the central nervous system (CNS). Although only a few drugs are available to symptomatic treatment, 'dopamine stabilizers' (as represented by the pridopidine) may be the new treatment options. The underlying causes of HD are dopaminergic conduction disorders. Initially, the disease is hyperkinetic (chorea) until it eventually reaches the hypokinetic phase. Studies confirmed a correlation between the amount of dopamine in the CNS and the stage of the disease. Pridopidine has the capacity to be a dopamine buffer, which could increase or decrease the dopamine content depending on the disease phase. A research carried out on animal models demonstrated the protective effect of pridopidine on nerve cells thanks to its ability to alter the cortical glutamatergic signaling through the N-methyl-D-aspartate (NMDA) receptors. Studies on dopamine stabilizers also reported that pridopidine has a 100-fold greater affinity for the sigma-1 receptor than for the D2 receptor. Disturbances in the activity of sigma-1 receptors occur in neurodegenerative diseases, including HD. Their interaction with pridopidine results in the neuroprotective effect, which is manifested as an increase in the plasticity of synaptic neurons and prevention of their atrophy within the striatum. To determine the effectiveness of pridopidine in the treatment of HD, large multicenter randomized studies such as HART, MermaiHD, and PRIDE-HD were carried out.

Topics: Animals; Dopamine; Humans; Motor Activity; Neurodegenerative Diseases; Neurons; Neuroprotective Agents; Piperidines

The vesicular acetylcholine transporter (VAChT), a presynaptic cholinergic neuron marker, is a potential internal molecular target for the development of an imaging agent for early diagnosis of neurodegenerative disorders with cognitive decline such as Alzheimer's disease (AD). Since vesamicol has been reported to bind to VAChT with high affinity, many vesamicol analogs have been studied as VAChT imaging agents for the diagnosis of cholinergic neurodeficit disorder. However, because many vesamicol analogs, as well as vesamicol, bound to sigma receptors (

Topics: Alzheimer Disease; Animals; Humans; Neurodegenerative Diseases; Piperidines; Radiopharmaceuticals; Structure-Activity Relationship; Vesicular Acetylcholine Transport Proteins

Reactive oxygen species (ROS) play an important role in physiological and pathological processes. In recent years, a feed-forward regulation of the ROS sources has been reported. The interactions between the main cellular sources of ROS, such as mitochondria and NADPH oxidases, however, remain obscure. This work summarizes the latest findings on the role of cross talk between mitochondria and NADPH oxidases in pathophysiological processes. Mitochondria have the highest levels of antioxidants in the cell and play an important role in the maintenance of cellular redox status, thereby acting as an ROS and redox sink and limiting NADPH oxidase activity. Mitochondria, however, are not only a target for ROS produced by NADPH oxidase but also a significant source of ROS, which under certain conditions may stimulate NADPH oxidases. This cross talk between mitochondria and NADPH oxidases, therefore, may represent a feed-forward vicious cycle of ROS production, which can be pharmacologically targeted under conditions of oxidative stress. It has been demonstrated that mitochondria-targeted antioxidants break this vicious cycle, inhibiting ROS production by mitochondria and reducing NADPH oxidase activity. This may provide a novel strategy for treatment of many pathological conditions including aging, atherosclerosis, diabetes, hypertension, and degenerative neurological disorders in which mitochondrial oxidative stress seems to play a role. It is conceivable that the use of mitochondria-targeted treatments would be effective in these conditions.

Topics: Aging; Angiotensin II; Animals; Antioxidants; Atherosclerosis; Diabetes Mellitus; Humans; Hypertension; Mice; Mitochondria; NADPH Oxidases; Neurodegenerative Diseases; Nitric Oxide Synthase Type III; Organophosphorus Compounds; Oxidation-Reduction; Oxidative Stress; Piperidines; Rabbits; Rats; Reactive Oxygen Species; Signal Transduction; Superoxide Dismutase; Xanthine Oxidase

The term 'dementia' encompasses a number of neurodegenerative diseases of which Alzheimer's disease (AD) is the most common. Prior to 2003, cholinesterase inhibitors, such as donezepil, were the only class of drugs approved to treat mild-to-moderate AD. In 2003, memantine became the first drug approved by the US FDA to treat moderate-to-severe AD. Currently, both memantine and donepezil are FDA approved for the treatment of moderate-to-severe AD. This article examines the pharmacologic profile of memantine, evidence for memantine's efficacy in moderate-to-severe AD and other dementias, its novel use in other neuropsychiatric disorders and future implications and research directions for memantine.

Topics: Alzheimer Disease; Cholinesterase Inhibitors; Dementia; Donepezil; Dopamine Agents; Humans; Indans; Memantine; Neurodegenerative Diseases; Piperidines

Filamentous tau inclusions are hallmarks of Alzheimer's disease (AD) and related tauopathies, and the discovery of mutations in the tau gene in frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17) constitutes convincing evidence that tau proteins play a key role in the pathogenesis of neurodegenerative disorders. To investigate the pathomechanism of tauopathies, we generated and studied P301S mutant human tau transgenic mice (line PS19). Filamentous tau lesions developed in PS19 mice at 6-months of age, and progressively accumulated in association with striking neuron loss as well as hippocampal and entorhinal cortical atrophy by 9-12 months of age. Remarkably, hippocampal synapse loss and impaired synaptic function were detected in 3 month old PS19 mice before fibrillary tau tangles emerged. Prominent microglial activation and proinflammatory cytokine expressions in neurons also preceded tangle formation. Importantly, immunosuppression of young PS19 mice with FK506 attenuated tau pathology, thereby linking neuroinflammation to early progression of tauopathies. Recently, an anti-inflammatory function of acetylcholine (ACh) has been reported, suggesting that synaptic dysfunction might accelerate neuroinflammatory reaction by depletion of ACH. To investigate this, we administered donepezil (DZ), an ACh-esterase inhibitor, and trihexiphenidyl (TP), an anti-cholinergic agent to PS19 mice. Interestingly, DZ ameliorated but TP deteriorated microglial activation, tau pathology and neuronal loss, indicating the ACh level in the brain might play roles in not only neurotransmission, but also suppressing neuroinflammation in the brain.

Topics: Acetylcholine; Amyloid; Animals; Brain; Cholinesterase Inhibitors; Disease Models, Animal; Donepezil; Humans; Immunosuppressive Agents; Indans; Inflammation; Mice; Mice, Transgenic; Microglia; Mutation; Neurodegenerative Diseases; Piperidines; Synapses; Tacrolimus; tau Proteins

Topics: Animals; Cognition; Donepezil; Drug Design; Extracellular Signal-Regulated MAP Kinases; Hippocampus; Humans; Indans; Lithium Carbonate; Nerve Regeneration; Neurodegenerative Diseases; Piperidines; Stimulation, Chemical; Valproic Acid; Vanadium Compounds

The advent of the highly selective cannabinoid receptor (CB1) antagonist, rimonabant (SR141716; Acomplia) can revolutionize the ability of the clinicians to manage obesity. Large-scale clinical trials have demonstrated that rimonabant therapy can reduce obesity. Although, the precise mechanisms of action of rimonabant have to be further dissected, it is emerging, from both preclinical and clinical research, that not only is rimonabant an antiobesity drug, but also its pleiotropic functions affect a broad range of diseases, from obesity-related comorbidities to drug dependence and cancer. Here we review recent data from the literature and discuss the full pharmacological potential of this drug.

Topics: Anti-Obesity Agents; Antineoplastic Agents; Body Weight; Humans; Neurodegenerative Diseases; Obesity; Piperidines; Pyrazoles; Receptor, Cannabinoid, CB1; Rimonabant; Smoking Cessation; Substance-Related Disorders

Nicotinamide adenine dinucleotide (NAD(+)) has crucial roles in many cellular processes, both as a coenzyme for redox reactions and as a substrate to donate ADP-ribose units. Enzymes involved in NAD(+) metabolism are attractive targets for drug discovery against a variety of human diseases, including cancer, multiple sclerosis, neurodegeneration and Huntington's disease. A small-molecule inhibitor of nicotinamide phosphoribosyltransferase, an enzyme in the salvage pathway of NAD(+) biosynthesis, is presently in clinical trials against cancer. An analog of a kynurenine pathway intermediate is efficacious against multiple sclerosis in an animal model. Indoleamine 2,3-dioxygenase plays an important role in immune evasion by cancer cells and other disease processes. Inhibitors against kynurenine 3-hydroxylase can reduce the production of neurotoxic metabolites while increasing the production of neuroprotective compounds. This review summarizes the existing knowledge on NAD(+) metabolic enzymes, with emphasis on their relevance for drug discovery.

Topics: Acrylamides; Adenosine Diphosphate Ribose; Aging; Animals; Antineoplastic Agents; Autoimmune Diseases; Clinical Trials, Phase II as Topic; Cyclic ADP-Ribose; DNA Damage; Drug Design; Enzyme Inhibitors; Humans; Kynurenine; Mice; NAD; Neoplasms; Neurodegenerative Diseases; Neuroprotective Agents; Piperidines; Poly Adenosine Diphosphate Ribose; Signal Transduction; Sirtuins; Tryptophan

Treatments for the symptomatic relief of Alzheimer's disease are available but despite advances in our ability to treat persons with various forms of dementia, more effective treatments are needed. The cholinesterase inhibitors donepezil, rivastigmine, and galantamine have demonstrated efficacy in improving cognition and global status and to a lesser extent, behavioral abnormalities relative to placebo in patients with mild-to-moderate Alzheimer's disease. Rivastigmine has been shown to benefit patients with dementia with Lewy Bodies and with dementia associated with Parkinson's disease. Donepezil and galantamine have also been shown to be mildly effective in dementia due to cerebral ischemia. Memantine has a distinct mechanism of action and is effective in moderate-to-severe AD. The benefits from these drugs, however, are limited and their long-term effectiveness has not been well-demonstrated. Their clinical utility is controversial. Many novel approaches that promise to provide more effective treatments are currently being pursued.

Topics: Acetylcholine; Alzheimer Disease; Cholinesterase Inhibitors; Dementia; Donepezil; Galantamine; Humans; Indans; Lewy Body Disease; Neurodegenerative Diseases; Neuroprotective Agents; Parkinson Disease; Phenylcarbamates; Piperidines; Rivastigmine; Tacrine

Caloric restriction (CR) is a dietary regimen known to promote lifespan by slowing down the occurrence of age-dependent diseases. The greatest risk factor for neurodegeneration in the brain is age, from which follows that CR might also attenuate the progressive loss of neurons that is often associated with impaired cognitive capacities. In this study, we used a transgenic mouse model that allows for a temporally and spatially controlled onset of neurodegeneration to test the potentially beneficial effects of CR. We found that in this model, CR significantly delayed the onset of neurodegeneration and synaptic loss and dysfunction, and thereby preserved cognitive capacities. Mechanistically, CR induced the expression of the known lifespan-regulating protein SIRT1, prompting us to test whether a pharmacological activation of SIRT1 might recapitulate CR. We found that oral administration of a SIRT1-activating compound essentially replicated the beneficial effects of CR. Thus, SIRT1-activating compounds might provide a pharmacological alternative to the regimen of CR against neurodegeneration and its associated ailments.

Topics: Analysis of Variance; Animals; Atrophy; Brain; Caloric Restriction; Case-Control Studies; Cognition Disorders; Cyclin-Dependent Kinase 5; Disease Models, Animal; Double-Blind Method; Excitatory Postsynaptic Potentials; Female; Green Fluorescent Proteins; Immunoprecipitation; In Vitro Techniques; Long-Term Potentiation; Male; Memory Disorders; Mice; Mice, Transgenic; Microscopy, Electron, Transmission; Nerve Tissue Proteins; Neurodegenerative Diseases; Phosphopyruvate Hydratase; Phosphotransferases; Piperidines; Silver Staining; Sirtuin 1; Synapses; Thiazoles; Tumor Suppressor Protein p53; Vitamin E

Sigma-1 receptor (S1R) has been considered a promising therapeutic target for several neurodegenerative diseases and S1R agonists have shown neuroprotective activity against glutamate excitotoxicity and oxidative stress. Starting from a previously identified low nanomolar S1R agonist, in this work we prepared and tested novel benzylpiperidine/benzylpiperazine-based compounds designed by applying a ring opening strategy. Among them, 4-benzyl-1-(2-phenoxyethyl)piperidine 6b (S1R Ki = 0.93 nM) and 4-benzyl-1-(3-phenoxypropyl)piperidine 8b (S1R Ki = 1.1 nM) emerged as high affinity S1R ligands and showed selectivity over S2R and N-methyl-d-aspartate receptor (NMDAR). Candidate compounds behaved as potent S1R agonists being able to enhance the neurite outgrowth induced by nerve growth factor (NGF) in PC12 cell lines. In SH-SY5Y neuroblastoma cell lines they exhibited a neuroprotective effect against rotenone- and NMDA-mediated toxic insults. The neuroprotective activity of 6b and 8b was reverted by co-treatment with an S1R antagonist, PB212. Compounds 6b and 8b were tested for cytotoxicity in-vitro against three human cancer cell lines (A549, LoVo and Panc-1) and in-vivo zebrafish model, resulting in a good efficacy/safety profile, comparable or superior to the reference drug memantine. Overall, these results encourage further preclinical investigations of 6b and 8b on in-vivo models of neurodegenerative diseases.

Topics: Animals; Humans; N-Methylaspartate; Neuroblastoma; Neurodegenerative Diseases; Neuroprotective Agents; Oxidative Stress; Piperidines; Receptors, sigma; Zebrafish

Alzheimer's disease (AD) is a neurodegenerative disease, often characterized by progressive deficits in memory and cognitive functions. Cholinesterase inhibitors have been introduced as promising agents to enhance cognition and memory in both human patients and animal models of AD. In the current study, we assessed the effects of a synthetic phenoxyethyl piperidine derivative, compound 7c, as a novel dual inhibitor of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), on learning and memory, as well as serum and hippocampal AChE levels in an animal model of AD. The model of dementia was induced by intracerebroventricular injection of streptozotocin (STZ, 2 mg/kg) to male Wistar rats. STZ-treated rats received compound 7c (3, 30, and 300 µg/kg) for five consecutive days. ​Passive avoidance (PA) learning and memory, as well as spatial learning and memory using Morris water maze, were evaluated. The level of AChE was measured in the serum and the left and right hippocampus. Findings demonstrated that compound 7c (300 µg/kg) was able to reverse STZ-induced impairments in PA memory, while also reduced the increased AChE level in the left hippocampus. Taken together, compound 7c appeared to act as a central AChE inhibitor, and its role in alleviating cognitive deficits in the AD animal model suggests that it may have therapeutic potential in AD dementia. Further research is required to assess the effectiveness of compound 7c in more reliable models of AD in light of these preliminary findings.

Topics: Acetylcholinesterase; Alzheimer Disease; Animals; Butyrylcholinesterase; Cholinesterase Inhibitors; Disease Models, Animal; Humans; Male; Maze Learning; Memory Disorders; Neurodegenerative Diseases; Piperidines; Rats; Rats, Wistar; Streptozocin

Amyotrophic lateral sclerosis (ALS) is a lethal and incurable neurodegenerative disease due to the loss of upper and lower motor neurons, which leads to muscle weakness, atrophy, and paralysis. Sigma-1 receptor (σ-1R) is a ligand-operated protein that exhibits pro-survival and anti-apoptotic properties. In addition, mutations in its codifying gene are linked to development of juvenile ALS pointing to an important role in ALS. Here, we investigated the disease-modifying effects of pridopidine, a σ-1R agonist, using a delayed onset SOD1 G93A mouse model of ALS. Mice were administered a continuous release of pridopidine (3.0 mg/kg/day) for 4 weeks starting before the appearance of any sign of muscle weakness. Mice were monitored weekly and several behavioural tests were used to evaluate muscle strength, motor coordination and gait patterns. Pridopidine-treated SOD1 G93A mice showed genotype-specific effects with the prevention of cachexia. In addition, these effects exhibited significant improvement of motor behaviour 5 weeks after treatment ended. However, the survival of the animals was not extended. In summary, these results show that pridopidine can modify the disease phenotype of ALS-associated cachexia and motor deficits in a SOD1 G93A mouse model.

Topics: Amyotrophic Lateral Sclerosis; Animals; Cachexia; Disease Models, Animal; Mice; Mice, Transgenic; Muscle Weakness; Neurodegenerative Diseases; Phenotype; Piperidines; Superoxide Dismutase; Superoxide Dismutase-1

Amyotrophic lateral sclerosis (ALS) is a fatal and incurable neurodegenerative disease with few therapeutic options. However, the immune system, including natural killer (NK) cells, is linked to ALS progression and may constitute a viable therapeutic ALS target. Tofacitinib is an FDA-approved immunomodulating small molecule which suppresses immune cell function by blocking proinflammatory cytokine signaling. This includes the cytokine IL-15 which is the primary cytokine associated with NK cell function and proliferation. However, the impact of tofacitinib on NK activation and cytotoxicity has not been thoroughly investigated, particularly in ALS. We therefore tested the ability of tofacitinib to suppress cytotoxicity and cytokine production in an NK cell line and in primary NK cells derived from control and ALS participants. We also investigated whether tofacitinib protected ALS neurons from NK cell cytotoxicity. Finally, we conducted a comprehensive pharmacokinetic study of tofacitinib in mice and tested the feasibility of administration formulated in chow. Success was assessed through the impact of tofacitinib on peripheral NK cell levels in mice. We found tofacitinib suppressed IL-15-induced activation as measured by STAT1 phosphorylation, cytotoxicity, pro-inflammatory gene expression, and pro-inflammatory cytokine secretion in both an NK cell line and primary NK cells. Furthermore, tofacitinib protected ALS neurons from NK cell-mediated cytotoxicity. In mice, we found tofacitinib bioavailability was 37% in both male and female mice; using these data we formulated mouse containing low and high doses of tofacitinib and found that the drug suppressed peripheral NK cell levels in a dose-dependent manner. These results demonstrate that tofacitinib can suppress NK cell function and may be a viable therapeutic strategy for ALS.

Topics: Amyotrophic Lateral Sclerosis; Animals; Apoptosis; Cytokines; Female; Humans; Killer Cells, Natural; Male; Mice; Neurodegenerative Diseases; Piperidines; Pyrimidines; Signal Transduction

Human immunodeficiency virus type 1 (HIV-1) is known to provoke microglial immune responses which likely play a paramount role in the development of chronic neuroinflammatory conditions and neuronal damage related to HIV-1 associated neurocognitive disorders (HAND). In particular, HIV-1 Tat protein is a proinflammatory neurotoxin which predisposes neurons to synaptodendritic injury. Drugs targeting the degradative enzymes of endogenous cannabinoids have shown promise in reducing inflammation with minimal side effects in rodent models. Considering that markers of neuroinflammation can predict the extent of neuronal injury in HAND patients, we evaluated the neurotoxic effect of HIV-1 Tat-exposed microglia following blockade of fatty acid amid hydrolyze (FAAH), a catabolic enzyme responsible for degradation of endocannabinoids, e.g. anandamide (AEA). In the present study, cultured murine microglia were incubated with Tat and/or a FAAH inhibitor (PF3845). After 24 h, cells were imaged for morphological analysis and microglial conditioned media (MCM) was collected. Frontal cortex neuron cultures (DIV 7-11) were then exposed to MCM, and neurotoxicity was assessed via live cell calcium imaging and staining of actin positive dendritic structures. Results demonstrate a strong attenuation of microglial responses to Tat by PF3845 pretreatment, which is indicated by 1) microglial changes in morphology to a less proinflammatory phenotype using fractal analysis, 2) a decrease in release of neurotoxic cytokines/chemokines (MCP-1/CCL2) and matrix metalloproteinases (MMPs; MMP-9) using ELISA/multiplex assays, and 3) enhanced production of endocannabinoids (AEA) using LC/MS/MS. Additionally, PF3845's effects on Tat-induced microglial-mediated neurotoxicity, decreased dysregulation of neuronal intracellular calcium and prevented the loss of actin-positive staining and punctate structure in frontal cortex neuron cultures. Interestingly, these observed neuroprotective effects appeared to be independent of cannabinoid receptor activity (CB

Topics: Amidohydrolases; Animals; Animals, Newborn; Cells, Cultured; Mice; Mice, Inbred C57BL; Mice, Knockout; Microglia; Neurodegenerative Diseases; Neuroprotection; Neuroprotective Agents; Piperidines; Pyridines; Receptors, G-Protein-Coupled; tat Gene Products, Human Immunodeficiency Virus

Parkinson's disease (PD) is the most common progressive neurodegenerative disease known to impart bradykinesia leading to diverse metabolic complications. Currently, scarcity of effective drug candidates against this long-term devastating disorder poses a big therapeutic challenge. Here, we have synthesized biocompatible, polycrystalline, and uniform piperine-coated gold nanoparticles (AuNPs

Topics: Alkaloids; Animals; Benzodioxoles; Drosophila melanogaster; Gold; Metal Nanoparticles; Neurodegenerative Diseases; Oxidative Stress; Paraquat; Piperidines; Polyunsaturated Alkamides

Waldenstrom's macroglobulinaemia (WM) is a lymphoproliferative disorder of the B cell origin. It is characterised by the presence of IgM paraprotein in the serum and lymphoplasmacytic lymphoma cells in the bone marrow with extranodal involvement relatively uncommon. Bing-Neel syndrome (BNS) is a neurological complication of WM that results from infiltration of the central nervous system by malignant lymphoplasmacytic cells. We present an interesting case of BNS that responded remarkably to ibrutinib monotherapy.

Topics: Adenine; Brain; Female; Humans; Magnetic Resonance Imaging; Middle Aged; Mutation; Myeloid Differentiation Factor 88; Neurodegenerative Diseases; Piperidines; Pyrazoles; Pyrimidines; Syndrome; Waldenstrom Macroglobulinemia

Parkinson's disease (PD) is a multifactorial neurological disorder caused by selective dopaminergic neuronal loss. Quercetin (QC) in combination with piperine (bioenhancer) acts as potential antioxidant, anti-inflammatory and neuroprotective against 6-OHDA rat model of PD. Rats were injected 6-OHDA (8μg/2μl, saline) unilaterally, intranigrally once into right SNpc. Pre-treatment with QC (25 and 50mg/kg, p.o.) alone and combination of QC (25mg/kg, p.o.) with piperine (2.5mg/kg, p.o.) were given for 14days starting from 8th day of 6-OHDA infusion. Post lesions were confirmed by rotational behavior with amphetamine (2.5mg/kg, i.p.) and motor coordination was assessed by narrow beam walk, open field and rotarod apparatus on the weekly basis. On 22nd day, animals were sacrificed and striatum homogenates were used for biochemical (LPO, GSH, Nitrite), neuroinflammatory (TNF-α, IL-1 β and IL-6) and neurotransmitter (dopamine, norepinephrine, serotonin, GABA, glutamate) analysis. Rats pre-treated with QC alone and in combination with piperine have significantly attenuated the 6-OHDA induced rotational behavior and motor deficits. Further, these drugs have significantly improved antioxidant potential, decreased striatal proinflammatory cytokines level as well as restored neurotransmitters level. The neuroprotective enhancement of QC along with piperine is attributed through antioxidant, anti-inflammatory and preventing neurotransmitter alteration mechanisms.

Topics: Alkaloids; Animals; Benzodioxoles; Brain Chemistry; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Therapy, Combination; Glutathione; Hand Strength; Locomotion; Male; Neurodegenerative Diseases; Neuroprotective Agents; Neurotransmitter Agents; Nitrites; Oxidopamine; Piperidines; Polyunsaturated Alkamides; Psychomotor Performance; Quercetin; Rats; Rats, Wistar; Sympatholytics; Thiobarbituric Acid Reactive Substances; Time Factors

ASS234 is a new multitarget molecule with multiple neuroprotective actions that significantly elevate mRNA levels of NRF2 and HSF1 transcriptional factors and of HSP105, HSP90AB1, HSPA1A, HSPA1B, HSPA5, HSPA8, HSPA9, HSP60, DNAJA1, DNAJB1, DNAJB6, DNAJC3, DNAJC5, DNAJC6, HSPB1, HSPB2, HSPB5, HSPB6, HSPB8, and HSP10 heat shock proteins (HSPs) family members in SH-SY5Y cells. This NRF2 and HSF1 overexpression may explain the upregulation of both the antioxidant enzymes previously described and the members of the HSPs family observed. These findings suggest that ASS234 is a potent HSPs inductor, which might be beneficial for preventing protein misfolding aggregation and cell death in Alzheimer's disease and other neurodegenerative diseases.

Topics: Antioxidants; Cell Line, Tumor; Endoplasmic Reticulum Chaperone BiP; Heat-Shock Proteins; Humans; Indoles; Neurodegenerative Diseases; Neuroprotective Agents; Piperidines; Up-Regulation

Pimavanserin is not curative, but can improve the quality of life remaining for the person with Parkinson's disease who typically has been suffering from this relentless neurodegenerative disease for years. Using pimavanserin effectively requires knowledge not only about the product itself, but also about the treatments pimavanserin is replacing.

Topics: Antipsychotic Agents; Consensus; Humans; Neurodegenerative Diseases; Off-Label Use; Parkinson Disease; Piperidines; Psychotic Disorders; Quality of Life; Urea

The therapy of complex neurodegenerative diseases requires the development of multitarget-directed drugs (MTDs). Novel indole derivatives with inhibitory activity towards acetyl/butyrylcholinesterases and monoamine oxidases A/B as well as the histamine H

Topics: Animals; Antioxidants; Blood-Brain Barrier; Cholinesterase Inhibitors; Cognitive Dysfunction; Drug Design; Histamine H3 Antagonists; Humans; Indoles; Ligands; Mice; Monoamine Oxidase Inhibitors; Neurodegenerative Diseases; Neuroprotective Agents; Piperidines

The aim of the present study was to investigate the protective effects of curcumin alone and in combination with piperine against lipopolysaccharide (LPS)-induced neurobehavioral and neurochemical deficits in the mice hippocampus. Mice were treated with curcumin (100, 200, and 400 mg/kg, p.o.) and piperine (20 mg/kg, p.o.) for 7 days followed by LPS (0.83 mg/kg, i.p.) administration. Animals exhibited anxiety and depressive-like phenotype after 3 and 24 h of LPS exposure, respectively. LPS administration increased the oxido-nitrosative stress as evident by elevated levels of malondialdehyde, nitrite, and depletion of glutathione level in the hippocampus. Furthermore, we found raised level of pro-inflammatory cytokines (IL-1β and TNF-α) in the hippocampus of LPS-treated mice. Pretreatment with curcumin alleviated LPS-induced neurobehavioral and neurochemical deficits. Furthermore, co-administration of curcumin with piperine significantly potentiated the neuroprotective effect of curcumin. These results demonstrate that piperine enhanced the neuroprotective effect of curcumin against LPS-induced neurobehavioral and neurochemical deficits.

Topics: Alkaloids; Animals; Benzodioxoles; Curcumin; Drug Synergism; Hippocampus; Lipopolysaccharides; Mice; Neurodegenerative Diseases; Neuroprotective Agents; Piperidines; Polyunsaturated Alkamides

Parkinson's disease (PD) is frequently associated with gastrointestinal (GI) symptoms, including constipation and defecatory dysfunctions. The mechanisms underlying such disorders are still largely unknown, although the occurrence of a bowel inflammatory condition has been hypothesized. This study examined the impact of central dopaminergic degeneration, induced by intranigral injection of 6-hydroxydopamine (6-OHDA), on distal colonic excitatory tachykininergic motility in rats.. Animals were euthanized 4 and 8 weeks after 6-OHDA injection. Tachykininergic contractions, elicited by electrical stimulation or exogenous substance P (SP), were recorded in vitro from longitudinal muscle colonic preparations. SP, tachykininergic NK1 receptor, and glial fibrillary acidic protein (GFAP) expression, as well as the density of eosinophils and mast cells in the colonic wall, were examined by immunohistochemical analysis. Malondialdehyde (MDA, colorimetric assay), TNF, and IL-1β (ELISA assay) levels were also examined. The polarization of peritoneal macrophages was evaluated by real-time PCR.. In colonic preparations, electrically and SP-evoked tachykininergic contractions were increased in 6-OHDA rats. Immunohistochemistry displayed an increase in SP and GFAP levels in the myenteric plexus, as well as NK1 receptor expression in the colonic muscle layer of 6-OHDA rats. MDA, TNF, and IL-1β levels were increased also in colonic tissues from 6-OHDA rats. In 6-OHDA rats, the number of eosinophils and mast cells was increased as compared with control animals, and peritoneal macrophages polarized towards a pro-inflammatory phenotype.. The results indicate that the induction of central nigrostriatal dopaminergic degeneration is followed by bowel inflammation associated with increased oxidative stress, increase in pro-inflammatory cytokine levels, activation of enteric glia and inflammatory cells, and enhancement of colonic excitatory tachykininergic motility.

Topics: Animals; Benzoxazoles; Disease Models, Animal; Dopamine; Enteric Nervous System; Eosinophils; Gastrointestinal Diseases; Gastrointestinal Motility; Glial Fibrillary Acidic Protein; Indoles; Male; Mast Cells; Neurodegenerative Diseases; Oxidopamine; Piperidines; Rats; Rats, Sprague-Dawley; Receptors, Neurokinin-1; Substance P; Sympatholytics; Tyrosine 3-Monooxygenase

Intracranial implants elicit neurodegeneration via the foreign body response (FBR) that includes BBB leakage, macrophage/microglia accumulation, and reactive astrogliosis, in addition to neuronal degradation that limit their useful lifespan. Previously, monocyte chemoattractant protein 1 (MCP-1, also CCL2), which plays an important role in monocyte recruitment and propagation of inflammation, was shown to be critical for various aspects of the FBR in a tissue-specific manner. However, participation of MCP-1 in the brain FBR has not been evaluated. Here we examined the FBR to intracortical silicon implants in MCP-1 KO mice at 1, 2, and 8 weeks after implantation. MCP-1 KO mice had a diminished FBR compared to WT mice, characterized by reductions in BBB leakage, macrophage/microglia accumulation, and astrogliosis, and an increased neuronal density. Moreover, pharmacological inhibition of MCP-1 in implant-bearing WT mice maintained the increased neuronal density. To elucidate the relative contribution of microglia and macrophages, bone marrow chimeras were generated between MCP-1 KO and WT mice. Increased neuronal density was observed only in MCP-1 knockout mice transplanted with MCP-1 knockout marrow, which indicates that resident cells in the brain are major contributors. We hypothesized that these improvements are the result of a phenotypic switch of the macrophages/microglia polarization state, which we confirmed using PCR for common activation markers. Our observations suggest that MCP-1 influences neuronal loss, which is integral to the progression of neurological disorders like Alzheimer's and Parkinson disease, via BBB leakage and macrophage polarization.

Topics: Animals; Benzoxazines; Blood-Brain Barrier; Brain; Cell Survival; Chemokine CCL2; Chronic Disease; Foreign-Body Reaction; Macrophages; Mice; Mice, Inbred C57BL; Mice, Knockout; Microglia; Neurodegenerative Diseases; Neurons; Piperidines; Prostheses and Implants; Receptors, CCR2; Tissue Engineering

Patients with temporal lobe epilepsy (TLE) often suffer from comorbid psychiatric diagnoses such as depression, anxiety, or impaired cognitive performance. Endocannabinoid (eCB) signaling is a key regulator of synaptic neurotransmission and has been implicated in the mechanisms of epilepsy as well as several mood disorders and cognitive impairments.. We employed a pilocarpine model of TLE in C57/BJ mice to investigate the role of eCB signaling in epileptogenesis and concomitant psychiatric comorbidities.. We sought to alter the neuronal levels of a known eCB receptor ligand, 2-arachidonylglycerol (2-AG), through the use of RHC80267 or JZL184. Pilocarpine-treated mice were treated with RHC80267 (1.3 μmol) or JZL184 (20 mg/kg) immediately after the termination of status epilepticus (SE), which was followed by daily treatment for the next 7 days. Our results indicated that RHC80267 treatment significantly reduced the percentage of mice suffering from spontaneous recurrent seizures (SRS) in addition to decreasing the duration of observed seizures when compared to vehicle treatment. Furthermore, RHC80267 attenuated depression and anxiety-related behaviors, improved previously impaired spatial learning and memory, and inhibited seizure-induced hippocampal neuronal loss during the chronic epileptic period. In contrast, JZL184 administration markedly increased the frequency and the duration of observed SRS, enhanced the previously impaired neuropsychological performance, and increased hippocampal damage following SE.. These findings suggest that RHC80267 treatment after the onset of SE could result in an amelioration of the effects found during the chronic epileptic period and yield an overall decrease in epileptic symptoms and comorbid conditions. Thus, alterations to endocannabinoid signaling may serve as a potential mechanism to prevent epileptogenesis and manipulation of this signaling pathway as a possible drug target.

Topics: Animals; Anticonvulsants; Benzodioxoles; Cyclohexanones; Disease Models, Animal; Electroencephalography; Epilepsy, Temporal Lobe; Exploratory Behavior; Hindlimb Suspension; Hippocampus; Male; Maze Learning; Mice; Mice, Inbred C57BL; Neurodegenerative Diseases; Piperidines

Hyperactivation of GluN2B subunit containing N-methyl-d-aspartate receptors (NMDARs) significantly contributes to the development of several neurodegenerative diseases through a process called excitotoxicity. NMDARs are voltage-gated Ca2+ channels which when activated lead to excessive influx of Ca2+ into neurons thereby exacerbating several calcium-dependent pathways that cause oxidative stress and apoptosis. Several drugs are presently in use to counter the NMDAR-mediated excitotoxic events among which Ifenprodil and its derivatives are GluN2B selective allosteric antagonists. Certain non-steroidal anti-inflammatory drugs (NSAIDs) have also been reported to inhibit NMDARs and the resultant pathologies. Meanwhile, Piroxicam, which is a NSAID, has been reported to be protective in cerebral ischemia-induced neurodegeneration through various pathways. Since Piroxicam has more number of interacting groups as compared to other NSAIDs and also has structural similarities with Ifenprodil, we thought it prudent that Piroxicam may inhibit NMDARs similar to Ifenprodil. By using molecular docking as a tool, we validated the hypothesis and hereby report for the first time that Piroxicam can inhibit GluN2B containing NMDARs through allosteric mode similar to the well known selective antagonist--Ifenprodil; and thus can be a therapeutic drug for the prevention of excitotoxic neurodegeneration.

Topics: Allosteric Site; Anti-Inflammatory Agents, Non-Steroidal; Apoptosis; Calcium; Cells, Cultured; Humans; Ligands; Models, Biological; Neurodegenerative Diseases; Neurons; Neuroprotective Agents; Oxidative Stress; Piperidines; Piroxicam; Protein Binding; Protein Conformation; Receptors, N-Methyl-D-Aspartate

(i) To describe patient and public involvement (PPI) in a network promoting research in dementia and neurodegenerative diseases, in terms of activity at the different stages of the research cycle and within the different levels of the research network. (ii) To use case studies to try and answer the question: what benefits (if any) does PPI in research bring to the research process?. PPI in health research is a central part of government policy, but the evidence base underpinning it needs strengthening. PPI allows exploration of feasibility, acceptability and relevance of hypotheses, assists in the precise definition of research questions and increases accrual to studies. However, the measurement of outcomes is methodologically difficult, because the impact of lay researchers may occur through team interactions and be difficult to untangle from the efforts of professional researchers. Opportunities for PPI in rapidly progressive diseases may be limited, and involvement of people with marked cognitive impairment is particularly challenging.. (i) Description of PPI within the DeNDRoN network. (ii) Case studies of three research projects which asked for extra help from centrally organized PPI.. PPI in research projects on the DeNDRoN portfolio may function at different levels, occurring at project, local research network and national level. Case studies of three research projects show different roles for PPI in research and different functions for centrally organized PPI, including contribution to remedial action in studies that are not recruiting to target, solving problems because of the complexity and sensitivity of the research topic, and linking researchers to PPI resources.. The case studies suggest that centrally organized PPI can have 'diagnostic' and remedial functions in studies that are struggling to recruit and serve as reinforcement for study-level PPI in the complex and sensitive research topics that are typical in neurodegenerative diseases research. PPI may be actively sought by researchers, but the infrastructure of PPI is not yet so widespread in the research community that lay researchers are easy to find; a centrally organized PPI resource can assist in this situation.

Topics: Alzheimer Disease; Biomedical Research; Community Participation; Dementia; Donepezil; Humans; Indans; Memantine; Neurodegenerative Diseases; Nootropic Agents; Organizational Case Studies; Patient Participation; Piperidines

The 1'-organyl-1,2,3,4-tetrahydrospiro[naphthalene-1,4'-piperidine] derivatives 1 a-4 a [for which organyl=benzyl (1 a), 4-methoxybenzyl (2 a), 2-phenylethyl (3 a), or 3-methylbut-2-enyl (4 a)] are high-affinity, selective σ₁ ligands. The corresponding sila-analogues 1 b-4 b (replacement of the carbon spirocenter with a silicon atom) were synthesized in multistep syntheses, starting from dichlorodivinylsilane, and were isolated as the hydrochlorides 1 b⋅HCl-4 b⋅HCl. Compounds 1 a⋅HCl-4 a⋅HCl and 1 b⋅HCl-4 b⋅HCl were structurally characterized by NMR spectroscopy (¹H, ¹³C, ²⁹Si) in solution, and the C/Si analogues 3 a⋅HCl and 3 b⋅HCl were studied by single-crystal X-ray diffraction. These structural investigations were complemented by computational studies. The σ₁ and σ₂ receptor affinities of the C/Si pairs 1 a/1 b-4 a/4 b were studied with radioligand binding assays. The σ₁ receptor affinity of the silicon compounds 1 b-4 b is slightly higher than that of the corresponding carbon analogues 1 a-4 a. Because affinity for the σ₂ receptor is decreased by the C/Si exchange, the σ₁/σ₂ selectivity of the silicon compounds is considerably improved, indicating that the C→Si switch strategy is a powerful tool for modulating both pharmacological potency and selectivity.

Topics: Animals; Binding Sites; Brain; Carbon; Crystallography, X-Ray; Guinea Pigs; Humans; Ligands; Liver; Magnetic Resonance Spectroscopy; Models, Molecular; Naphthalenes; Neurodegenerative Diseases; Neuroprotective Agents; Piperidines; Radioligand Assay; Rats; Receptors, sigma; Silicon; Structure-Activity Relationship

Although a blockade of acetylcholine esterase has been reported to suppress neuronal cell death induced by exogenous glutamate and beta-amyloid, information is still limited regarding the neuroprotective effects of the acetylcholine esterase inhibitor donepezil. We histologically examined the effects of donepezil on neuronal injury induced by ischemia-reperfusion. Intravenous and intravitreous treatment with donepezil 15 min prior to ischemia dramatically reduced the retinal damage. The protective effect of donepezil in the ganglion cell layer was not affected by mecamylamine, a nicotinic acetylcholine-receptor antagonist, nor scopolamine, a muscarinic acetylcholine-receptor antagonist. The protective effect of donepezil in the inner plexiform layer was reduced not by mecamylamine, but by scopolamine. Neostigmine, a choline-esterase inhibitor, and pilocarpine, a muscarinic acetylcholine-receptor agonist, have protective effects in the inner plexiform layer and the inner nuclear layer. These results suggest that not only the activation of acetylcholine receptors but also a mechanism unrelated to acetylcholine-esterase inhibition contribute to the protective effect of donepezil on the ganglion cells in the ischemic-reperfused rat retina. Donepezil may be useful as a therapeutic drug against retinal diseases that cause neuronal cell death such as glaucoma with high intraocular pressure.

Topics: Animals; Donepezil; Indans; Male; Neurodegenerative Diseases; Neuroprotective Agents; Piperidines; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Retinal Degeneration; Retinal Vessels; Vitreous Body

The CHDI Fifth Annual HD Therapeutics Conference, held in Palm Springs, CA, included topics covering new therapeutic developments in the field of Huntington's disease (HD). This conference report highlights presentations on biomarkers in HD; emerging topics in drug targeting, such as the lysosomal degradation pathway and target prediction by network-based modeling; understanding phenotype and neuronal circuit dysfunction in animal models; regulation of huntingtin protein expression and function; RNAi and antisense technology to deplete the mutant huntingtin protein; and small-molecule drugs that are progressing quickly through the clinic. Investigational drugs discussed include ALN-HTT (Alnylam Pharmaceuticals Inc/Medtronic Inc), EPI-743 (Edison Pharmaceuticals Inc), LNK-754 (Link Medicine Corp) and pridopidine (NeuroSearch A/S).

Topics: Animals; Biomarkers; Disease Models, Animal; Dopamine; Drug Delivery Systems; Enzyme Inhibitors; Farnesyltranstransferase; Humans; Huntingtin Protein; Huntington Disease; Leigh Disease; Lysosomes; Models, Biological; Nerve Tissue Proteins; Neurodegenerative Diseases; Nuclear Proteins; Oligonucleotides, Antisense; Phosphorylation; Piperidines; RNA, Small Interfering; Sheep; Sirtuin 1; Ubiquinone

The term neurological diseases includes a lot of disorders concerning both the central and peripheral nervous system. Low incidence on the one hand and anaesthetic relevance on the other hand requires special attention in preoperative preparing and management of general anaesthesia. The following paper presents special problems of neurodegenerative disorders, which anaesthetic relevance is of growing interest in the changed elderly population.

Topics: Anesthesia, General; Anesthetics, Inhalation; Anesthetics, Intravenous; Autonomic Nervous System; Brain; Bromocriptine; Dopamine Agonists; Humans; Intubation; Levodopa; Monoamine Oxidase Inhibitors; Muscle Relaxants, Central; Nervous System Diseases; Neurodegenerative Diseases; Neurosurgery; Parkinson Disease; Piperidines; Premedication; Preoperative Care; Propofol; Remifentanil; Selegiline; Stereotaxic Techniques; Syndrome

Corticobasal degeneration is a progressive neurological disorder characterized by a combination of parkinsonism and cortical dysfunction such as limb kinetic apraxia, alien limb phenomenon, and dementia. To study the effect of repetitive facilitation exercise (RFE) in a patient with corticobasal degeneration, we used a newly designed facilitation exercise designed to elicit movements isolated from the synergy in hemiplegia. This exercise included movements of each isolated finger using stretch reflex and skin-muscle reflex and repetitive movements demanded in activities of daily living (ADL) and manipulating objects. To evaluate improvements in hand functions by RFE, 1-week RFE sessions for the hand were administered alternatively to the left or right hand. The number of finger taps by the hand increased during each 1-week RFE session for the hand, but did not increase during 1-week sessions without RFE. After 1 month of treatment, the patient's difficulties in ADL, including wearing clothes, manipulating objects and cooking, decreased. Our results suggest the importance of the repetition of facilitation exercises and movements in ADL for recovery in patients with degenerative neurogenic diseases.

Topics: Activities of Daily Living; Apraxia, Ideomotor; Cholinesterase Inhibitors; Disease Progression; Donepezil; Female; Frontal Lobe; Hand; Humans; Indans; Middle Aged; Muscle Stretching Exercises; Neurodegenerative Diseases; Neurologic Examination; Parkinsonian Disorders; Piperidines; Recovery of Function

A 58-year-old man presented with a history of disturbance in initiating gait. His history revealed meningoencephalitis five years prior to admission. Neurological examination included gait disturbance as difficulty in initiation and a hesitating speech with many freezing episodes and micrographia Magnetic resonance imaging (MRI) showed diffuse hyperintensity of frontal subcortical white matter on T2 weighted images. He was diagnosed with PA. L-Dopa up to the dosages of 1000 mg/ day and selegiline 10 mg/day were given. First brain SPECT using technetium-99m labeled D,L-hexamethylpropylene amine oxime (Tc-99m HMPAO) was performed when he was taking L-dopa and selegiline. In visual evaluation, hypoperfusion in bilateral frontoparietal cortex was seen (Fig. 2). Treatment with L-dopa and selegiline produced no benefit. Donepezil 10 mg/day was begun. This therapy regimen resulted in dramatic clinical improvement within several days that was confirmed by blinded raters who watched the patient's video recordings. During this response second brain perfusion SPECT study was repeated during donepezil therapy. Markedly increased perfusion in bilateral frontoparietal cortex was observed. This is the first case of PA to develop possibly after an episode of bacterial pneumococcal meningoencephalitis and who responded to donepezil as documented by changes in clinical findings and Tc-99m HMPAO brain SPECT studies.

Topics: Alexia, Pure; Brain; Cholinesterase Inhibitors; Dementia; Donepezil; Gait Disorders, Neurologic; Indans; Neurodegenerative Diseases; Piperidines; Radiopharmaceuticals; Recovery of Function; Syndrome; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Treatment Outcome

A number of recent studies surveying single nucleotide polymorphisms within the exonic regions of human genes have revealed a significant number of such variants, including many non-synonymous variants. This highlights the need to directly identify, within individual clinically well-defined patients, those variants that alter protein function as well as structure. We report on the development of a novel phenotypic screening process that combines high-throughput molecular cloning techniques with functional expression utilizing the cell-based assay R-SAT.. We applied the phenotypic screening process to an analysis of the m1 muscarinic acetylcholine receptor (CHRM1) gene in a cohort of 74 individuals, including 48 diagnosed with neurodegenerative disease, primarily Alzheimer disease, who have been stratified according to their clinical response to the acetylcholinesterase inhibitor donepezil. Phenotypic screening of the CHRM1 gene involved PCR-based amplification from genomic DNA and heterologous expression in mammalian cells.. Phenotypic screening yielded functional responses to the agonist carbachol displaying a mean potency (-pEC(50)+/- standard deviation) of 5.8 +/- 0.2, which did not differ from that observed with expression of the wild-type receptor gene (6.0 +/- 0.3). No altered levels of constitutive receptor activity were observed. Dideoxy sequencing did not reveal any non-synonymous variants in the coding exon of this gene within this clinical cohort, while detecting three synonymous variants.. The results confirm that the m1 receptor gene (CHRM1) is not highly polymorphic in the human population, suggesting that genetic variation within the coding exon of this gene is not a contributing factor to the clinical variability observed during treatment of dementia with cholinergic enhancement therapies.

Topics: Aged; Cholinesterase Inhibitors; Cohort Studies; Dementia; DNA; Donepezil; Drug Delivery Systems; Female; Genetic Testing; Humans; Indans; Male; Neurodegenerative Diseases; Nootropic Agents; Phenotype; Piperidines; Polymorphism, Genetic; Receptor, Muscarinic M1; Receptors, Muscarinic; Reverse Transcriptase Polymerase Chain Reaction

Seven days after the injection of different concentrations of thrombin into the nigrostriatal pathway, a strong macrophage/microglial reaction was observed in the substantia nigra (SN), indicated by immunostaining, using OX-42 and OX-6 antibodies, and by the induction of iNOS, IL-1alpha, Il-1beta and TNF-alpha. Moreover, selective damage to dopaminergic neurones was produced after thrombin injection, evidenced by loss of tyrosine hydroxylase immunostaining and tyrosine hydroxylase mRNA-expressing cell bodies, and the unaltered transcription of glutamic acid decarboxylase mRNA in the SN and striatum. These thrombin effects could be produced by its ability to induce the activation of microglia described in in vitro studies, and are in agreement with the effects described for other proinflammatory compounds. Thrombin effects are produced by its biological activity since they almost disappeared when thrombin was heat-inactivated or injected along with its inhibitor alpha-NAPAP. Thrombin is a multi-functional serine protease rapidly produced from prothrombin at the sites of tissue injury, and also upon breakdown of the blood-brain barrier, which strongly suggests it could easily enter into the CNS. These results could have special importance in some degenerative processes of the nigrostriatal dopaminergic system.

Topics: Animals; Antithrombins; Corpus Striatum; Dipeptides; Dopamine; Dose-Response Relationship, Drug; Enzyme Induction; Female; In Situ Hybridization; Interleukin-1; Microglia; Microinjections; Neurodegenerative Diseases; Neurons; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Piperidines; Rats; Rats, Wistar; RNA, Messenger; Substantia Nigra; Thrombin; Tumor Necrosis Factor-alpha; Tyrosine 3-Monooxygenase

Extrusion of one of the nitrogens of the piperazine ring of potent nootropic drugs previously described gave 4-aminopiperidine analogues that maintained high cognition enhancing activity in the mouse passive avoidance test. One of the new compounds (9, active at 0.01 mg/kg ip) may represent a new lead for the development of cognition enhancers useful to treat the cognitive deficit produced by neurodegenerative pathologies like Alzheimer's disease.

Topics: Amnesia; Animals; Avoidance Learning; Chemical Phenomena; Chemistry, Physical; Cognition; Dose-Response Relationship, Drug; Indicators and Reagents; Mice; Muscarinic Antagonists; Neurodegenerative Diseases; Nootropic Agents; Piperidines; Receptors, AMPA; Scopolamine; Structure-Activity Relationship

We evaluated the potencies of radioiodinated (-)-o-iodovesamicol [(-)-oIV] as a selective vesicular acetylcholine transporter (VAChT) mapping agent. (-)-[125I]oIV exhibited significant accumulation (about 2.8% of the injected dose) in rat brain. The regional brain distribution of radioactivity was similar for both (-)-[125I]olV and (-)-[3H]vesamicol. The accumulation of (-)-[125I]oIV in the brain was significant reduced by post-administration of unlabeled vesamicol (0.5 /micromol/kg(-1)) and (-)-oIV (0.5 micromol/kg(-1)). On the other hand, the post-administration of sigma ligands hardly affected the accumulation of (-)-[125I]oIV in the brain. These studies showed that (-)-[125I]oIV, as well as [3H] vesamicol, bound to VAChT with high affinity in the rat brain. Furthermore, (-)-[125I]oIV binding in the ipsilateral cortex to the lesion was significantly reduced by 17.0%, compared with that in the contralateral cortex in a unilateral NBM-lesioned rat. These results suggested that radioiodinated (-)-oIV may potentially be useful for the diagnosis of cholinergic neurodegenerative disorders.

Topics: Animals; Brain; Carrier Proteins; Ibotenic Acid; Iodine Radioisotopes; Isotope Labeling; Male; Membrane Transport Proteins; Metabolic Clearance Rate; Neurodegenerative Diseases; Organ Specificity; Piperidines; Radionuclide Imaging; Radiopharmaceuticals; Rats; Reproducibility of Results; Sensitivity and Specificity; Tissue Distribution; Vesicular Acetylcholine Transport Proteins; Vesicular Transport Proteins

A new method for quantitative measurement of brain acetylcholinesterase (AChE) activity in living human brain using positron emission tomography (PET) is described. We tested several radiolabeled lipophilic acetylcholine analogs, e.g., N-methylpiperidyl esters, which readily entered the brain via the blood-brain barrier, were hydrolyzed selectively by AChE, and were then trapped in the brain. Among them, and tested and N-[11C]methylpiperidin-4-yl acetate ([11C]MP4A) was chosen as the tracer for PET. Quantitative measurement of cortical AChE was accomplished by fitting the time course of cerebral radioactivity concentration measured by PET and the metabolite-corrected arterial plasma input function using a nonlinear least-squares fitting method. Normal control studies of subjects with a wide range in age (24-89 years) showed no decrease in AChE activity in the cerebral cortex with age. Studies on patients with Alzheimer's disease demonstrated a widespread reduction of AChE activity in the cerebral cortex (more profound in early-onset than in late-onset Alzheimer's disease). Parkinson's disease and progressive supranuclear palsy, clinically similar disorders, could be differentiated with [11C]MP4A/PET studies. Simple methods without using an arterial input function are also proposed. The method provides a quantitative measure of the cholinergic aspect of brain function and proved to be useful in diagnosis of neurodegenerative disorders including Alzheimer's disease.

Topics: Acetylcholinesterase; Adult; Aged; Aged, 80 and over; Aging; Brain; Carbon Radioisotopes; Female; Half-Life; Humans; Kinetics; Male; Middle Aged; Neurodegenerative Diseases; Piperidines; Radioactive Tracers; Reference Values; Tomography, Emission-Computed

The ability of cannabinoid CB(1) receptors to influence glutamatergic excitatory neurotransmission has fueled interest in how these receptors and their endogenous ligands may interact in conditions of excitotoxic insults. The present study characterized the impact of stimulated and inhibited CB(1) receptor function on NMDA-induced excitotoxicity. Neonatal (6-day-old) rat pups received a systemic injection of a mixed CB(1) /CB(2) receptor agonist (WIN55,212-2) or their respective antagonists (SR141716A for CB(1) and SR144528 for CB(2) ) prior to an unilateral intrastriatal microinjection of NMDA. The NMDA-induced excitotoxic damage in the ipsilateral forebrain was not influenced by agonist-stimulated CB(1) receptor function. In contrast, blockade of CB(1), but not CB(2), receptor activity evoked a robust neuroprotective response by reducing the infarct area and the number of cortical degenerating neurons. These results suggest a critical involvement of CB(1) receptor tonus on neuronal survival following NMDA receptor-induced excitotoxicity in vivo.

Topics: Animals; Benzoxazines; Brain; Cannabinoids; Cell Survival; Cerebral Cortex; Corpus Striatum; Morpholines; N-Methylaspartate; Naphthalenes; Neurodegenerative Diseases; Neurotoxins; Parietal Lobe; Piperidines; Pyrazoles; Rats; Rats, Sprague-Dawley; Receptor, Cannabinoid, CB2; Receptors, Cannabinoid; Receptors, Drug; Rimonabant