8,987 results match your criteria enhanced hippocampal

Artemisinin-treatment in pre-symptomatic APP-PS1 mice increases gephyrin phosphorylation at Ser270: a modification regulating postsynaptic GABAR density.

Biol Chem 2021 Apr 20. Epub 2021 Apr 20.

Institute of Anatomy and Cell Biology, University of Heidelberg, Im Neuenheimer Feld 307, D-69120Heidelberg, Germany.

Artemisinins, a group of plant-derived sesquiterpene lactones, are efficient antimalarial agents. They also share anti-inflammatory and anti-viral activities and were considered for treatment of neurodegenerative disorders like Alzheimer's disease (AD). Additionally, artemisinins bind to gephyrin, the multifunctional scaffold of GABAergic synapses, and modulate inhibitory neurotransmission . Read More

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Shortened tethering filaments stabilize presynaptic vesicles in support of elevated release probability during LTP in rat hippocampus.

Proc Natl Acad Sci U S A 2021 Apr;118(17)

Department of Neuroscience, Center for Learning and Memory, Institute for Neuroscience, University of Texas at Austin, Austin, TX 78712;

Long-term potentiation (LTP) is a cellular mechanism of learning and memory that results in a sustained increase in the probability of vesicular release of neurotransmitter. However, previous work in hippocampal area CA1 of the adult rat revealed that the total number of vesicles per synapse decreases following LTP, seemingly inconsistent with the elevated release probability. Here, electron-microscopic tomography (EMT) was used to assess whether changes in vesicle density or structure of vesicle tethering filaments at the active zone might explain the enhanced release probability following LTP. Read More

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Elevated anxiety, hypoactivity, memory deficits, decreases of brain serotonin and 5-HT-1A receptors expression in rats treated with omeprazole.

Toxicol Res 2021 Apr 17;37(2):237-248. Epub 2020 Sep 17.

Present Address: Neuroscience Research Laboratory, Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi, 75270 Pakistan.

Omeprazole (OM) is one of the most prescribed drugs worldwide for the treatment of hyperacidity and gastric reflux. However, concerns regarding its safety have emerged recently, and the drug is reported to enhance the risk for anxiety and cognitive deficits, particularly in elderly patients. The present study investigated these adverse effects, if any, in adult male rats. Read More

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Sustained Hippocampal Synaptic Pathophysiology Following Single and Repeated Closed-Head Concussive Impacts.

Front Cell Neurosci 2021 31;15:652721. Epub 2021 Mar 31.

Center for Neurodegenerative Disease and Therapeutics, Rosalind Franklin University of Medicine and Science, North Chicago, IL, United States.

Traumatic brain injury (TBI), and related diseases such as chronic traumatic encephalopathy (CTE) and Alzheimer's (AD), are of increasing concern in part due to enhanced awareness of their long-term neurological effects on memory and behavior. Repeated concussions, vs. single concussions, have been shown to result in worsened and sustained symptoms including impaired cognition and histopathology. Read More

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Secreted Amyloid Precursor Protein-Alpha Enhances LTP Through the Synthesis and Trafficking of Ca-Permeable AMPA Receptors.

Front Mol Neurosci 2021 1;14:660208. Epub 2021 Apr 1.

Department of Anatomy, Brain Health Research Centre, Brain Research New Zealand - Rangahau Roro Aotearoa, University of Otago, Dunedin, New Zealand.

Regulation of AMPA receptor expression by neuronal activity and neuromodulators is critical to the expression of both long-term potentiation (LTP) and memory. In particular, Ca-permeable AMPARs (CP-AMPAR) play a unique role in these processes due to their transient, activity-regulated expression at synapses. Secreted amyloid precursor protein-alpha (sAPPα), a metabolite of the parent amyloid precursor protein (APP) has been previously shown to enhance hippocampal LTP as well as memory formation in both normal animals and in Alzheimer's disease models. Read More

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Dietary spermidine improves cognitive function.

Cell Rep 2021 Apr;35(2):108985

Institute of Molecular Biosciences, NAWI Graz, University of Graz, 8010 Graz, Austria; BioTechMed-Graz, 8010 Graz, Austria; Field of Excellence BioHealth, University of Graz, 8010 Graz, Austria. Electronic address:

Decreased cognitive performance is a hallmark of brain aging, but the underlying mechanisms and potential therapeutic avenues remain poorly understood. Recent studies have revealed health-protective and lifespan-extending effects of dietary spermidine, a natural autophagy-promoting polyamine. Here, we show that dietary spermidine passes the blood-brain barrier in mice and increases hippocampal eIF5A hypusination and mitochondrial function. Read More

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Attenuation of the extracellular matrix increases the number of synapses but suppresses synaptic plasticity through upregulation of SK channels.

Cell Calcium 2021 Apr 8;96:102406. Epub 2021 Apr 8.

Department of Molecular Neurobiology, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya Street 16/10, Moscow, 117997, Russia; Department of Physiology, Jiaxing University College of Medicine, Zhejiang, 314033 China; Sechenov First Moscow State Medical University, Bolshaya Pirogovskaya Str 19с1, Moscow, 119146, Russia. Electronic address:

The effect of brain extracellular matrix (ECM) on synaptic plasticity remains controversial. Here, we show that targeted enzymatic attenuation with chondroitinase ABC (ChABC) of ECM triggers the appearance of new glutamatergic synapses on hippocampal pyramidal neurons, thereby increasing the amplitude of field EPSPs while decreasing both the mean miniature EPSC amplitude and AMPA/NMDA ratio. Although the increased proportion of 'unpotentiated' synapses caused by ECM attenuation should promote long-term potentiation (LTP), surprisingly, LTP was suppressed. Read More

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Effect of arsenic-containing hydrocarbon on the long-term potentiation at Schaffer Collateral-CA1 synapses from infantile male rat.

Neurotoxicology 2021 Apr 10;84:198-207. Epub 2021 Apr 10.

Institute of Chemistry, NAWI Graz, University of Graz, 8010, Graz, Austria. Electronic address:

Arsenic-containing hydrocarbons (AsHCs) are common constituents of marine organisms and have potential toxicity to human health. This work is to study the effect of AsHCs on long-term potentiation (LTP) for the first time. A multi-electrode array (MEA) system was used to record the field excitatory postsynaptic potential (fEPSP) of CA1 before and after treatment with AsHC 360 in hippocampal slices from infantile male rats. Read More

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Mechanisms of microRNA‑142 in mitochondrial autophagy and hippocampal damage in a rat model of epilepsy.

Int J Mol Med 2021 Jun 13;47(6). Epub 2021 Apr 13.

Department of Neurology, The First Hospital of Changsha, Changsha, Hunan 410013, P.R. China.

Researchers have confirmed the microRNA (miRNA/miR)‑epilepsy association in rodent models of human epilepsy via a comprehensive database. However, the mechanisms of miR‑142 in epilepsy have not been extensively studied. In the present study, a rat model of epilepsy was first established by an injection of lithium chloride‑pilocarpine and the successful establishment of the model was verified via electroencephalogram monitoring. Read More

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"Olfactory three-needle" acupuncture enhances synaptic function in Aβ-induced Alzheimer's disease via activating PI3K/AKT/GSK-3β signaling pathway.

J Integr Neurosci 2021 Mar;20(1):55-65

College of Acu-moxibustion and Massage, Shaanxi University of Chinese Medicine, 712046 Xianyang, P. R. China.

Synaptic dysfunction and neuronal loss are related to cognitive impairment of Alzheimer's disease. Recent evidence indicates that regulating the phosphatidylinositol 3-Kinase (PI3K)/AKT/GSK-3β pathway is a therapeutic strategy for improving synaptic plasticity in Alzheimer's disease. Here, we investigated "olfactory three-needle" effects on synaptic function and the PI3K/AKT/GSK-3β signaling pathway in β-amyloid (Aβ)-induced Alzheimer's disease rats. Read More

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The immediate early gene is not required for hippocampal long-term potentiation.

J Neurosci 2021 Apr 6. Epub 2021 Apr 6.

Department of Neurobiology, University of Utah.

Memory consolidation is thought to occur through protein synthesis-dependent synaptic plasticity mechanisms such as long-term potentiation (LTP). Dynamic changes in gene expression and epigenetic modifications underlie the maintenance of LTP. Similar mechanisms may mediate the storage of memory. Read More

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Glucocorticoids: Dr. Jekyll and Mr. Hyde of Hippocampal Neuroinflammation.

Biochemistry (Mosc) 2021 Feb;86(2):156-167

Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, 117485, Russia.

Glucocorticoids (GCs) are an important component of adaptive response of an organism to stressogenic stimuli, a typical stress response being accompanied by elevation of GC levels in blood. Anti-inflammatory effects of GCs are widely used in clinical practice, while pro-inflammatory effects of GCs are believed to underlie neurodegeneration. This is particularly critical for the hippocampus, brain region controlling both cognitive function and emotions/affective behavior, and selectively vulnerable to neuroinflammation and neurodegeneration. Read More

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February 2021

Increased excitatory synaptic transmission associated with adult seizure vulnerability induced by early life inflammation in mice.

J Neurosci 2021 Apr 6. Epub 2021 Apr 6.

Hotchkiss Brain Institute

Early life inflammatory-stress increases seizure susceptibility later in life. However, possible sex- and age-specific differences and the associated mechanisms are largely unknown. C57/BL6 mice were bred in house, and female and male pups were injected with lipopolysaccharide (LPS, 100 μg/kg ) or vehicle control (saline solution) at postnatal day 14 (p14). Read More

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Impaired spatial learning and suppression of sharp wave ripples by cholinergic activation at the goal location.

Elife 2021 Apr 6;10. Epub 2021 Apr 6.

Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom.

The hippocampus plays a central role in long-term memory formation, and different hippocampal network states are thought to have different functions in this process. These network states are controlled by neuromodulatory inputs, including the cholinergic input from the medial septum. Here, we used optogenetic stimulation of septal cholinergic neurons to understand how cholinergic activity affects different stages of spatial memory formation in a reward-based navigation task in mice. Read More

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Caffeine - treat or trigger? Disparate behavioral and long-term dopaminergic changes in control and schizophrenia-like Wisket rats.

Physiol Behav 2021 Apr 2;236:113410. Epub 2021 Apr 2.

Department of Physiology, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary.

The influence of caffeine on behavioral functions in both healthy and schizophrenic subjects is controversial. Here we aimed to reveal the effects of repeated caffeine pre- and post-training treatments on motor and exploratory activities and cognitive functions in a reward-based test (Ambitus) along with a brain region-specific dopamine D receptor profile in control and schizophrenia-like WISKET model rats. In the control animals, pre-treatment caused temporary enhancement in motor activity, while permanent improvement in learning function was detected in the WISKET animals. Read More

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Intracerebral Transplantation of Neural Stem Cells Restores Manganese-Induced Cognitive Deficits in Mice.

Aging Dis 2021 Apr 1;12(2):371-385. Epub 2021 Apr 1.

1Key Laboratory of Longevity and Aging-related Diseases of Chinese Ministry of Education, Guangxi Collaborative Innovation Center for Biomedicine & Guangxi Key Laboratory of Regenerative Medicine, Center for Translational Medicine, Guangxi Medical University, Nanning, Guangxi, China.

Manganese (Mn) is a potent neurotoxin known to cause long-lasting structural damage and progressive cognitive deficits in the brain. However, new therapeutic approaches are urgently needed since current treatments only target symptoms of Mn exposure. Recent studies have suggested a potential role for multipotent neural stem cells (NSCs) in the etiology of Mn-induced cognitive deficits. Read More

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Leucine-Enriched Essential Amino Acids Enhance the Antiseizure Effects of the Ketogenic Diet in Rats.

Front Neurosci 2021 19;15:637288. Epub 2021 Mar 19.

Department of Pharmacology, Jikei University School of Medicine, Minato-ku, Japan.

The classic ketogenic diet (KD) can be used successfully to treat medically refractory epilepsy. However, the KD reduces seizures in 50-70% of patients with medically refractory epilepsy, and its antiseizure effect is limited. In the current study, we developed a new modified KD containing leucine (Leu)-enriched essential amino acids. Read More

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Dipeptidyl-peptidase 3 protects oxygen-glucose deprivation/reoxygenation-injured hippocampal neurons by suppressing apoptosis, oxidative stress and inflammation via modulation of Keap1/Nrf2 signaling.

Int Immunopharmacol 2021 Mar 31;96:107595. Epub 2021 Mar 31.

Anesthesiology Department, The First Affiliated Hospital of China Medical University, Shenyang 110001, Liaoning Province, China. Electronic address:

Dipeptidyl-peptidase 3 (DPP3) plays a key role in regulating apoptosis, oxidative stress and inflammation under various pathological conditions, however, whether DPP3 regulates apoptosis and oxidative stress in neurons undergoing cerebral ischemia/reperfusion injury has not yet been well studied. The goals of this work were to evaluate the role of DPP3 in the regulation of oxygen-glucose deprivation/reoxygenation (OGD/R)-induced apoptosis, oxidative stress and inflammation in HT22 hippocampal neurons. Here, we showed that DPP3 expression was elevated in response to OGD/R in neurons. Read More

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Inhibition of Soluble Epoxide Hydrolase Ameliorates Phenotype and Cognitive Abilities in a Murine Model of Niemann Pick Type C Disease.

Int J Mol Sci 2021 Mar 26;22(7). Epub 2021 Mar 26.

Pharmacology and Toxicology Section and Institute of Neuroscience, Faculty of Pharmacy and Food Sciences, University of Barcelona, Av. Joan XXIII, 27-31, 08028 Barcelona, Spain.

Niemann-Pick type C (NPC) disease is a rare autosomal recessive inherited childhood neurodegenerative disease characterized by the accumulation of cholesterol and glycosphingolipids, involving the autophagy-lysosome system. Inhibition of soluble epoxide hydrolase (sEH), an enzyme that metabolizes epoxy fatty acids (EpFAs) to 12-diols, exerts beneficial effects in modulating inflammation and autophagy, critical features of the NPC disease. This study aims to evaluate the effects of UB-EV-52, an sEH inhibitor (sEHi), in an NPC mouse model (Npc) by administering it for 4 weeks (5 mg/kg/day). Read More

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Bi-Temporal Anodal Transcranial Direct Current Stimulation during Slow-Wave Sleep Boosts Slow-Wave Density but Not Memory Consolidation.

Brain Sci 2021 Mar 24;11(4). Epub 2021 Mar 24.

Translational Research Center, University Hospital of Psychiatry and Psychotherapy, University of Bern, 3000 Bern, Switzerland.

Slow-wave sleep (SWS) has been shown to promote long-term consolidation of episodic memories in hippocampo-neocortical networks. Previous research has aimed to modulate cortical sleep slow-waves and spindles to facilitate episodic memory consolidation. Here, we instead aimed to modulate hippocampal activity during slow-wave sleep using transcranial direct current stimulation in 18 healthy humans. Read More

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CaMKIIα Expressing Neurons to Report Activity-Related Endogenous Hypoxia upon Motor-Cognitive Challenge.

Int J Mol Sci 2021 Mar 20;22(6). Epub 2021 Mar 20.

Clinical Neuroscience, Max Planck Institute of Experimental Medicine, 37075 Göttingen, Germany.

We previously introduced the brain erythropoietin (EPO) circle as a model to explain the adaptive 'brain hardware upgrade' and enhanced performance. In this fundamental circle, brain cells, challenged by motor-cognitive tasks, experience functional hypoxia, triggering the expression of EPO among other genes. We attested hypoxic cells by a transgenic reporter approach under the ubiquitous CAG promoter, with Hif-1α oxygen-dependent degradation-domain (ODD) fused to CreERT2-recombinase. Read More

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Long-Term Caloric Restriction Attenuates β-Amyloid Neuropathology and Is Accompanied by Autophagy in APPswe/PS1delta9 Mice.

Nutrients 2021 Mar 18;13(3). Epub 2021 Mar 18.

Rudolf-Zenker-Institute for Experimental Surgery, Medical University Rostock, 18057 Rostock, Germany.

Caloric restriction (CR) slows the aging process, extends lifespan, and exerts neuroprotective effects. It is widely accepted that CR attenuates β-amyloid (Aβ) neuropathology in models of Alzheimer's disease (AD) by so-far unknown mechanisms. One promising process induced by CR is autophagy, which is known to degrade aggregated proteins such as amyloids. Read More

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Long-term depression-related tau phosphorylation is enhanced by methylene blue in healthy rat hippocampus.

Pharmacol Rep 2021 Apr 2. Epub 2021 Apr 2.

Department of Physiology, School of Medicine, Erciyes University, Kayseri, Turkey.

Background: The present study examined whether inhibition of guanylate cyclase (GC) is associated with the plasticity-related microtubule-stabilizing protein tau phosphorylation in the dentate gyrus (DG) of hippocampal formation.

Methods: To address this issue, methylene blue (MB 50 μM) or saline was infused into the DG starting from the induction of long-term potentiation (LTP) or depression (LTD) for 1 h. Then, protein phosphatase 1 alpha (PP1α), glycogen synthase kinase 3 beta (GSK3β), and tau total and phosphorylated protein levels were measured in these hippocampi using western blotting. Read More

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Absence of Pannexin 1 Stabilizes Hippocampal Excitability After Intracerebral Treatment With Aβ (1-42) and Prevents LTP Deficits in Middle-Aged Mice.

Front Aging Neurosci 2021 16;13:591735. Epub 2021 Mar 16.

Department of Neurophysiology, Medical Faculty, Ruhr University Bochum, Bochum, Germany.

Beta-amyloid protein [Aβ(1-42)] plays an important role in the disease progress and pathophysiology of Alzheimer's disease (AD). Membrane properties and neuronal excitability are altered in the hippocampus of transgenic AD mouse models that overexpress amyloid precursor protein. Although gap junction hemichannels have been implicated in the early pathogenesis of AD, to what extent Pannexin channels contribute to Aβ(1-42)-mediated brain changes is not yet known. Read More

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Cannabinoid CB and CB receptors differentially regulate TNF-α-induced apoptosis and LPA-mediated pro-survival signaling in HT22 hippocampal cells.

Life Sci 2021 Mar 29;276:119407. Epub 2021 Mar 29.

Laboratory of Cellular and Molecular Pharmacology, Section of Neurosciences, Department of Biomedical Sciences, University of Cagliari, Cagliari, Italy. Electronic address:

Aims: The aim of the study was to investigate the interaction between cannabinoid CB/CB and lysophosphatidic acid (LPA) receptors in controlling neuronal signaling and fate.

Methods: HT22 hippocampal cells were treated with different cannabinoid and LPA receptor agonists and antagonists. Western blot and immunofluorescence microscopy were used to study intracellular signaling and the expression of apoptotic markers. Read More

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Acute enhancing effect of a standardized extract of (ECa 233) on synaptic plasticity: an investigation via hippocampal long-term potentiation.

Pharm Biol 2021 Dec;59(1):367-374

Department of Physiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.

Context: ECa 233 is the standardized extract of (L.) Urban. (Apiaceae). Read More

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December 2021

Aqueous extract of Cola nitida and Garcinia kola synergistically enhances hippocampal-hypothalamic glutamate and Na+/K+-ATPase activity in male Wistar rats.

Curr Drug Discov Technol 2021 Mar 28. Epub 2021 Mar 28.

School of Laboratory Medicine & Medical Sciences, Nelson R Mandela School of Medicine, University of KwaZulu-Natal, Private Bag X54001, Congella 4013, Westville, Durban. South Africa.

Background: The incidence of cognitive decline has been proposed to rise exponentially in coming years. Therapies targeting molecular pathways involved in enhancement of memory and energy regulation could be a major breakthrough in prevention or management of dementia in susceptible populations.

Objectives: This study investigated the effects of aqueous extracts of Cola nitida (AECONS) and Garcinia kola (AEGAK) on glutamate level and Na+/K+-ATPase activity in the hippocampus and hypothalamus of male Wistar rats. Read More

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Inhibition of PTEN Ameliorates Secondary Hippocampal Injury and Cognitive Deficits after Intracerebral Hemorrhage: Involvement of AKT/FoxO3a/ATG-Mediated Autophagy.

Oxid Med Cell Longev 2021 18;2021:5472605. Epub 2021 Jan 18.

Department of Neurosurgery, Tangshan Gongren Hospital, Tangshan 063000, China.

Spontaneous intracerebral hemorrhage (ICH) commonly causes secondary hippocampal damage and delayed cognitive impairments, but the mechanisms remain elusive. Here, we sought to identify the molecular mechanisms underlying these hemorrhagic outcomes in a rat autologous blood model of ICH. First, a significant increase in phosphatase and tensin homolog (PTEN) expression was observed in nonhemorrhagic ipsilateral hippocampus. Read More

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January 2021

Altered hippocampal astroglial metabolism is associated with aging and preserved spatial learning and memory.

Neurobiol Aging 2021 Feb 26;102:188-199. Epub 2021 Feb 26.

Department of Physiology, Southern Illinois University School of Medicine, Carbondale, IL, USA; Department of Anatomy, Southern Illinois University School of Medicine, Carbondale, IL, USA; Center for Integrated Research in the Cognitive and Neural Sciences, Southern Illinois University School of Medicine, Carbondale, IL, USA. Electronic address:

An age-related decrease in hippocampal metabolism correlates with cognitive decline. Hippocampus-dependent learning and memory requires glutamatergic neurotransmission supported by glutamate-glutamine (GLU-GLN) cycling between neurons and astrocytes. We examined whether GLU-GLN cycling in hippocampal subregions (dentate gyrus and CA1) in Fischer 344 rats was altered with age and cognitive status. Read More

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February 2021

Targeting Alzheimer's disease with multimodal polypeptide-based nanoconjugates.

Sci Adv 2021 Mar 26;7(13). Epub 2021 Mar 26.

Polymer Therapeutics Lab., Centro de Investigación Príncipe Felipe (CIPF), Av. Eduardo Primo Yúfera 3, 46012 Valencia, Spain.

Alzheimer's disease (AD), the most prevalent form of dementia, remains incurable mainly due to our failings in the search for effective pharmacological strategies. Here, we describe the development of targeted multimodal polypeptide-based nanoconjugates as potential AD treatments. Treatment with polypeptide nanoconjugates bearing propargylamine moieties and bisdemethoxycurcumin or genistein afforded neuroprotection and displayed neurotrophic effects, as evidenced by an increase in dendritic density of pyramidal neurons in organotypic hippocampal culture. Read More

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