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Frontiers in Pharmacology 2023Stroke survivors are at significantly increased risk of cognitive impairment, which affects patients' independence of activities of daily living (ADLs), social...
Stroke survivors are at significantly increased risk of cognitive impairment, which affects patients' independence of activities of daily living (ADLs), social engagement, and neurological function deficit. Many studies have been done to evaluate the efficacy and safety of post-stroke cognitive impairment (PSCI) treatment, and due to the largely inconsistent clinical data, there is a need to summarize and analyze the published clinical research data in this area. An umbrella review was performed to evaluate the efficacy and safety of PSCI therapies. Three independent authors searched for meta-analyses and systematic reviews on PubMed, the Cochrane Library, and the Web of Science to address this issue. We examined ADL and Barthel index (BI), Montreal Cognitive Assessment (MoCA), neurological function deficit as efficacy endpoints, and the incidence of adverse events as safety profiles. In all, 312 studies from 19 eligible publications were included in the umbrella review. The results showed that angiotensin-converting enzyme inhibitors (ACEI) and N-methyl-D-aspartate (NMDA) antagonists, cell therapies, acupuncture, and EGB76 can improve the MoCA and ADL, and the adverse effects were mild for the treatment of PSCI. Moreover, Vinpocetine, Oxiracetam, Citicoline, thrombolytic therapy, Actovegin, DL-3-n-Butylphthalide, and Nimodipine showed adverse events or low article quality in patients with PSCI. However, the research evidence is not exact and further research is needed. Our study demonstrated that ACEI inhibitors (Donepezil) and NMDA antagonists (Memantine), EGB761, and acupuncture are the ADL and BI, MoCA, and neurological function deficit medication/therapy, respectively, for patients with PSCI. https://inplasy.com/inplasy-2022-11-0139/; Identifier: INPLASY2022110139.
PubMed: 37693907
DOI: 10.3389/fphar.2023.1207075 -
Ibrain 2023Memantine is a noncompetitive moderate-affinity strong voltage-dependent N-methyl-D-aspartate receptor antagonist. It has been used to treat Alzheimer's disease (AD)... (Review)
Review
Memantine is a noncompetitive moderate-affinity strong voltage-dependent N-methyl-D-aspartate receptor antagonist. It has been used to treat Alzheimer's disease (AD) since 1989. In 2018, it became the second most commonly used drug for the treatment of dementia in the world. AD is nonreversible, and memantine can only relieve the symptoms of AD but not cure it. Over the past half-century, memantine's research and clinical application have been extensively developed. In this review, the basic composition of memantine, the mechanism and limitations of memantine in the treatment of AD, memantine combination therapy, comparison of memantine with other drugs for AD, and clinical studies of memantine in other diseases are reviewed to provide a valuable reference for further research and application of memantine for the treatment of AD.
PubMed: 37786758
DOI: 10.1002/ibra.12098 -
Cureus Dec 2023Dementia is a debilitating neurological condition that is characterized by persistent cognitive decline. It is a global health challenge, with a rapidly increasing... (Review)
Review
Dementia is a debilitating neurological condition that is characterized by persistent cognitive decline. It is a global health challenge, with a rapidly increasing prevalence due to an increasing aging population. Although definitive diagnosis of various conditions of dementia is only possible by autopsy, clinical diagnosis can be performed by a specialist. The diagnostic process has evolved with recent breakthroughs in diagnostic tools, such as advanced imaging techniques and biomarkers. These tools facilitate early and accurate identification of the condition. Early diagnosis is vital, as it enables timely interventions to improve the quality of life for affected individuals. Treatment strategies for dementia encompass both pharmacological and non-pharmacological approaches. Non-pharmacological treatments include cognitive training and lifestyle modifications. Among pharmacological treatments, acetyl-cholinesterase inhibitors including donepezil, rivastigmine, and galantamine can be used in various doses based on the severity of the disease. Apart from these, N-methyl-D-aspartate receptor antagonists such as memantine can also be used. Furthermore, personalized treatments have also gained significant attention in dementia treatment. Interdisciplinary care, involving healthcare professionals, social workers, and support networks, is crucial for comprehensive and holistic dementia management.
PubMed: 38222245
DOI: 10.7759/cureus.50522 -
Biomarker Research Aug 2023Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with a dismal prognosis, and despite significant advances in our understanding of its genetic drivers,...
BACKGROUND
Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with a dismal prognosis, and despite significant advances in our understanding of its genetic drivers, like KRAS, TP53, CDKN2A, and SMAD4, effective therapies remain limited. Here, we identified a new therapeutic target GRIN2D and then explored its functions and mechanisms in PDAC progression.
METHODS
We performed a genome-wide RNAi screen in a PDAC xenograft model and identified GRIN2D, which encodes the GluN2D subunit of N-methyl-D-aspartate receptors (NMDARs), as a potential oncogene. Western blot, immunohistochemistry, and analysis on Gene Expression Omnibus were used for detecting the expression of GRIN2D in PDAC. Cellular experiments were conducted for exploring the functions of GRIN2D in vitro while subcutaneous and orthotopic injections were used in in vivo study. To clarify the mechanism, we used RNA sequencing and cellular experiments to identify the related signaling pathway. Cellular assays, RT-qPCR, and western blot helped identify the impacts of the NMDAR antagonist memantine.
RESULTS
We demonstrated that GRIN2D was highly expressed in PDAC cells, and further promoted oncogenic functions. Mechanistically, transcriptome profiling identified GRIN2D-regulated genes in PDAC cells. We found that GRIN2D promoted PDAC progression by activating the p38 MAPK signaling pathway and transcription factor CREB, which in turn promoted the expression of HMGA2 and IL20RB. The upregulated GRIN2D could effectively promote tumor growth and liver metastasis in PDAC. We also investigated the therapeutic potential of NMDAR antagonism in PDAC and found that memantine reduced the expression of GRIN2D and inhibited PDAC progression.
CONCLUSION
Our results suggested that NMDA receptor GRIN2D plays important oncogenic roles in PDAC and represents a novel therapeutic target.
PubMed: 37553583
DOI: 10.1186/s40364-023-00514-4 -
Biomedicine & Pharmacotherapy =... Jul 2023Diabetic retinopathy (DRET) triggers vision loss in adults, however, little therapeutic options are existing. Memantine is an anti-Alzheimer drug that antagonizes the...
Diabetic retinopathy (DRET) triggers vision loss in adults, however, little therapeutic options are existing. Memantine is an anti-Alzheimer drug that antagonizes the activity of glutamate at N-methyl-D-aspartate (NMDA) receptors. Glutamate and thioredoxin-interacting protein (TXNIP) are known to be overexpressed in diabetic retinas and can produce activation of NOD-like receptor protein 3 (NLRP3) with subsequent secretion of interlukin-1β. This study repurposed memantine for its neuroprotective effect in experimental DRET and tested its impact on ROS/TXNIP/NLRP3. In addition, KEGG pathway database and STRING database identified the protein-protein interaction between glutamate receptors and TXNIP/NLRP3. Male Swiss albino mice received alloxan (180 mg/kg) to induce DRET. After 9 weeks, we divided the mice into groups: (a) saline, (ii) DRET, (iii and iv) DRET + oral memantine (5 or 10 mg per kg) for 28 days. Then, mice were euthanized, and eyeballs were removed. Retinal samples were utilized for biochemical, histopathological, and electron microscopy studies. Retinal levels of glutamate, TXNIP, NLRP3 and interlukin-1β were estimated using ELISA technique as well as retinal malondialdehyde. Histopathological and ultrastructural examination demonstrated that oral memantine attenuated vacuolization and restored normal retinal cell layers. Moreover, memantine reduced TXNIP, NLRP3, interleukin-1β and MDA concentrations. These results provide evidence demonstrating memantine' efficacy in alleviating DRET via suppressing reactive oxygen species/TXNIP/NLRP3 signaling cascade. Therefore, memantine might serve as a potential therapy for retinopathy after adequate clinical research.
Topics: Mice; Male; Animals; NLR Family, Pyrin Domain-Containing 3 Protein; Diabetic Retinopathy; Inflammasomes; Reactive Oxygen Species; Memantine; NLR Proteins; Glutamates; Thioredoxins; Diabetes Mellitus; Carrier Proteins
PubMed: 37116352
DOI: 10.1016/j.biopha.2023.114772 -
Epilepsia Dec 2023N-methyl-d-aspartate (NMDA) receptors are expressed at synaptic sites, where they mediate fast excitatory neurotransmission. NMDA receptors are critical to brain...
OBJECTIVE
N-methyl-d-aspartate (NMDA) receptors are expressed at synaptic sites, where they mediate fast excitatory neurotransmission. NMDA receptors are critical to brain development and cognitive function. Natural variants to the GRIN1 gene, which encodes the obligatory GluN1 subunit of the NMDA receptor, are associated with severe neurological disorders that include epilepsy, intellectual disability, and developmental delay. Here, we investigated the pathogenicity of three missense variants to the GRIN1 gene, p. Ile148Val (GluN1-3b[I481V]), p.Ala666Ser (GluN1-3b[A666S]), and p.Tyr668His (GluN1-3b[Y668H]).
METHODS
Wild-type and variant-containing NMDA receptors were expressed in HEK293 cells and primary hippocampal neurons. Patch-clamp electrophysiology and pharmacology were used to profile the functional properties of the receptors. Receptor surface expression was evaluated using fluorescently tagged receptors and microscopy.
RESULTS
Our data demonstrate that the GluN1(I481V) variant is inhibited by the open pore blockers ketamine and memantine with reduce potency but otherwise has little effect on receptor function. By contrast, the other two variants exhibit gain-of-function molecular phenotypes. Glycine sensitivity was enhanced in receptors containing the GluN1(A666S) variant and the potency of pore block by memantine and ketamine was reduced, whereas that for MK-801 was increased. The most pronounced functional deficits, however, were found in receptors containing the GluN1(Y668H) variant. GluN1(Y668H)/2A receptors showed impaired surface expression, were more sensitive to glycine and glutamate by an order of magnitude, and exhibited impaired block by extracellular magnesium ions, memantine, ketamine, and MK-801. These variant receptors were also activated by either glutamate or glycine alone. Single-receptor recordings revealed that this receptor variant opened to several conductance levels and activated more frequently than wild-type GluN1/2A receptors.
SIGNIFICANCE
Our study reveals a critical functional locus of the receptor (GluN1[Y668]) that couples receptor gating to ion channel conductance, which when mutated may be associated with neurological disorder.
Topics: Humans; Memantine; Dizocilpine Maleate; Receptors, N-Methyl-D-Aspartate; Ketamine; HEK293 Cells; Glutamates; Neurodevelopmental Disorders; Glycine; Nerve Tissue Proteins
PubMed: 37734923
DOI: 10.1111/epi.17776 -
Cureus Apr 2024Alzheimer's disease (AD) is the most common neurodegenerative condition and a form of dementia encountered in medical practice. Despite many proposed and attempted... (Review)
Review
Alzheimer's disease (AD) is the most common neurodegenerative condition and a form of dementia encountered in medical practice. Despite many proposed and attempted treatments, this disease remains a major puzzle in the public health systems worldwide. The initial part of this article provides an overview and illustration of the primary mechanisms responsible for neuronal damage in AD. Subsequently, it offers a critical evaluation of the most noteworthy studies on pharmacological therapy for AD and outlines recent advancements and novel approaches to managing this condition. Main properties, categorization, Food and Drug Administration (FDA) status, mechanisms of action, benefits, and common side effects of the classical and the most recently proposed pharmacological treatments for AD are described. The conventional pharmacological agents revised comprise cholinesterase inhibitors, monoclonal antibodies, and other therapies, such as memantine, valproic acid, and rosiglitazone. The innovative reviewed pharmacological agents comprise the monoclonal antibodies: donanemab, gantenerumab, solanezumab, bapineuzumab, crenezumab, and semorinemab. Nutritional supplements such as alpha-tocopherol (vitamin E) and caprylidene are also revised. Tau and amyloid-targeting treatments include methylthioninium moiety (MT), leuco-methylthioninium bis (LMTM), an oxidized form of MT, and tramiprosate, which inhibits the beta-amyloid (Aβ) monomer aggregation into toxic oligomers. Antidiabetic and anti-neuroinflammation drugs recently proposed for AD treatment are discussed. The antidiabetic drugs include NE3107, an anti-inflammatory and insulin sensitizer, and the diabetes mainstream drug metformin. The anti-neuroinflammatory AD therapies include the use of sodium oligomannate (GV-971), infusions with intravenous immunoglobulin aiming to decrease plasma levels of the constituents of Aβ plaques, and masitinib, a tyrosine kinase inhibitor that impacts mast and microglia cells. Additional anti-inflammatory agents being currently tested in phase-2 clinical trials, such as atomoxetine (selective norepinephrine reuptake inhibitor), losartan (angiotensin 2 receptor agonist), genistein (anti-inflammatory isoflavone neuroprotective agent), trans-resveratrol (polyphenol antioxidant plant estrogen), and benfotiamine (synthetic thiamine precursor), were reviewed. Lastly, drugs targeting Alzheimer's-associated symptoms, such as brexpiprazole (serotonin dopamine activity modulator) and suvorexant (orexin receptor antagonist), respectively, used for agitation and insomnia in AD patients, are reviewed. As experimental investigations and clinical research progress, there is a possibility that a combination of newly tested medications and traditional ones may emerge as a promising treatment option for AD in the future.
PubMed: 38756263
DOI: 10.7759/cureus.58416 -
Cells Jun 2023Memantine is an FDA-approved, non-competitive NMDA-receptor antagonist that has been shown to have mitochondrial protective effects, improve cell viability and enhance...
Memantine is an FDA-approved, non-competitive NMDA-receptor antagonist that has been shown to have mitochondrial protective effects, improve cell viability and enhance clearance of Aβ peptide. Currently, there are uncertainties regarding the precise molecular targets as well as the most favourable treatment concentrations of memantine. Here, we made use of an imaging-based approach to investigate the concentration-dependent effects of memantine on mitochondrial fission and fusion dynamics, autophagy and mitochondrial quality control using a neuronal model of CCCP-induced mitochondrial injury so as to better unpack how memantine aids in promoting neuronal health. GT1-7 murine hypothalamic cells were cultured under standard conditions, treated with a relatively high and low concentration (100 µM and 50 µM) of memantine for 48 h. Images were acquired using a Zeiss 780 PS1 platform. Utilising the mitochondrial event localiser (MEL), we demonstrated clear concentration-dependent effects of memantine causing a protective response to mitochondrial injury. Both concentrations maintained the mitochondrial network volume whilst the low concentration caused an increase in mitochondrial number as well as increased fission and fusion events following CCCP-induced injury. Additionally, we made use of a customised Python-based image processing and analysis pipeline to quantitatively assess memantine-dependent changes in the autophagosomal and lysosomal compartments. Our results revealed that memantine elicits a differential, concentration-dependent effect on autophagy pathway intermediates. Intriguingly, low but not high concentrations of memantine lead to the induction of mitophagy. Taken together, our findings have shown that memantine is able to protect the mitochondrial network by preserving its volume upon mitochondrial injury with high concentrations of memantine inducing macroautophagy, whereas low concentrations lead to the induction of mitophagy.
Topics: Mice; Animals; Mitophagy; Memantine; Carbonyl Cyanide m-Chlorophenyl Hydrazone; Autophagy; Mitochondria
PubMed: 37443760
DOI: 10.3390/cells12131726 -
Neuropharmacology Feb 2024The great potential for NMDA receptor modulators as druggable targets in neurodegenerative disorders has been met with limited success. Considered one of the rare... (Review)
Review
The great potential for NMDA receptor modulators as druggable targets in neurodegenerative disorders has been met with limited success. Considered one of the rare exceptions, memantine has consistently demonstrated restorative and prophylactic properties in many AD models. In clinical trials memantine slows the decline in cognitive performance associated with AD. Here, we provide an overview of the basic properties including pharmacological targets, toxicology and cellular effects of memantine. Evidence demonstrating reductions in molecular, physiological and behavioural indices of AD-like impairments associated with memantine treatment are also discussed. This represents both an extension and homage to Dr. Chris Parson's considerable contributions to our fundamental understanding of a success story in the AD treatment landscape.
Topics: Humans; Memantine; Alzheimer Disease; Receptors, N-Methyl-D-Aspartate; Cognition
PubMed: 37832633
DOI: 10.1016/j.neuropharm.2023.109737 -
Medicina Aug 2023There is a wealth of information on early pharmacological supportive treatment for early rehabilitation following acute ischemic stroke. This review aims to provide... (Review)
Review
There is a wealth of information on early pharmacological supportive treatment for early rehabilitation following acute ischemic stroke. This review aims to provide healthcare professionals involved in rehabilitating patients with a summary of the available evidence to assist with decision-making in their daily clinical practice. A search for randomized clinical trials and observational studies published between 1/1/2000 and 28/8/2022 was performed using PubMed, Cochrane and Epistemonikos as search engines with language restriction to english and spanish. The selected studies included patients older than 18 with acute ischemic stroke undergoing early rehabilitation. The outcomes considered for efficacy were: motor function, language, and central pain. The selected pharmacological interventions were: cerebrolysin, levodopa, selegiline, amphetamines, fluoxetine, citalopram, escitalopram, antipsychotics, memantine, pregabalin, amitriptyline and lamotrigine. Evidence synthesis and evaluation were performed using the GRADE methodology. This review provided a summary of the evidence on pharmacological supportive care in early rehabilitation of post-acute ischemic stroke patients. This will make it possible to improve current recommendations with the aim of collaborating with health decision-making for this population.
Topics: Humans; Ischemic Stroke; Medicine; Amitriptyline; Antipsychotic Agents; Citalopram
PubMed: 37624681
DOI: No ID Found