Strategy For Alzheimer's Disease Research Articles

APOE targeting strategy in Alzheimer’s disease: lessons learned from protective variants

APOE targeting strategy in Alzheimer’s disease: lessons learned from protective variants

Description of organizational and clinician characteristics of primary dementia care in Canada: a multi-method study

BackgroundOrganizational and clinician characteristics are important considerations for the implementation of evidence-based recommendations into primary care practice. The introduction of Canadian dementia practice guidelines and Alzheimer strategies offers a unique context to study which of the organizational and clinician characteristics align with good quality care in primary care practices.MethodsTo evaluate the quality of dementia care, we carried out a retrospective chart review in randomly selected patients with a diagnosis of dementia and who had a visit during a 9-month period in 33 primary care practices. We collected data on indicators that were based on existing Canadian evidence-based recommendations to measure a quality of dementia care score. In addition, four questionnaires were administered: two questionnaires to evaluate the organizational characteristics of the practices (dementia-specific and general organization) and two to evaluate the clinician characteristics (one for family physicians and one for nurses). Primary care practices were stratified into tertiles based on their average quality of dementia care score (low, moderate, high). The differences between the groups organizational and clinician questionnaires scores were analyzed descriptively and visually.ResultsThe mean overall scores for each questionnaire were higher in the high quality of dementia care group. When looking at the breakdown of the overall score into each characteristic, the high-quality group had a higher average score for the dementia-specific organizational characteristics of “access to and coordination with home and community services”, “financial support”, “training”, “coordination and continuity within the practice”, and “caregiver support and involvement”. The characteristic “Leadership” showed a higher average score for the moderate and high-quality groups than the low-quality group. In both clinician questionnaires, the high group scored better in “attitudes towards the Alzheimer’s plan” than the other two groups.ConclusionsThese results suggest that investing in organizational characteristics specifically aimed at dementia care is a promising avenue to improve quality of dementia care in primary care. These results may be useful to enhance the implementation of evidence-based practices and improve the quality of dementia care.

Age-dependent attenuation of spatial memory deficits by the histone acetyltransferase p300/CBP-associated factor (PCAF) in 3xTG Alzheimer's disease mice.

Histone acetylation, catalyzed by histone acetyltransferases, has emerged as a promising therapeutic strategy in Alzheimer's disease (AD). By longitudinally characterizing spatial memory at 3, 6, and 9 mo of age, we show that acute activation and inhibition of the histone acetyltransferase PCAF remediated memory impairments in 3xTG-AD mice in an age-related bidirectional manner. At 3 and 6 mo of age, PCAF activation ameliorated memory deficits. At 9 mo of age, PCAF activation had no effect on spatial memory, whereas PCAF inhibition improved memory deficits in females. This work reveals a complex potential therapeutic role for PCAF in AD, initially benefitting memory but becoming detrimental as the disease progresses.

Optogenetic neuromodulation with gamma oscillation as a new strategy for Alzheimer disease: a narrative review.

The amyloid hypothesis has been considered a major explanation of the pathogenesis of Alzheimer disease. However, failure of phase III clinical trials with anti-amyloid-beta monoclonal antibodies reveals the need for other therapeutic approaches to treat Alzheimer disease. Compared to its relatively short history, optogenetics has developed considerably. The expression of microbial opsins in cells using genetic engineering allows specific control of cell signals or molecules. The application of optogenetics to Alzheimer disease research or clinical approaches is increasing. When applied with gamma entrainment, optogenetic neuromodulation can improve Alzheimer disease symptoms. Although safety problems exist with optogenetics such as the use of viral vectors, this technique has great potential for use in Alzheimer disease. In this paper, we review the historical applications of optogenetic neuromodulation with gamma entrainment to investigate the mechanisms involved in Alzheimer disease and potential therapeutic strategies.

Interest of novel N-alkylpyridinium-indolizine hybrids in the field of Alzheimer's disease: Synthesis, characterization and evaluation of antioxidant activity, cholinesterase inhibition, and amyloid fibrillation interference

A small library of molecules combining indolizine and N-alkyl pyridinium was synthesized and evaluated in a multi-target-directed-ligand strategy for Alzheimer's disease (AD) treatment. The new compounds were classified in three series depending on the number of methylene residues linking the two heterocycles (Ind-PyCx with x = 0, 2 or 3). The molecules were synthesized from the corresponding bis-pyridines by two-step formation of the indolizine core including mono-alkylation of pyridine and 1,3-dipolar cycloaddition with an alkylpropiolate. Their activities against AD's key-targets were evaluated in vitro: acetyl- and butyrylcholinesterase (AChE and BChE) inhibition, antioxidant properties and inhibition of amyloid fibril formation. None of the three series showed significant activities against all the targets. The Ind-PyC2 and Ind-PyC3 series are active on eeAChE and hAChE (µM IC50 values). Most of the positively charged molecules from these two series also appeared active against eqBChE, however they lost their activity on hBChE. Comparative molecular modeling of 13 and 15 docked in hAChE and hBChE highlighted the importance of the substituent (p-methoxybenzoyl or methyloxycarbonyl, respectively) located on the indolizine C-3 for the binding. The larger molecule 13 fits more tightly at the active site of the two enzymes than 15 that shows a larger degree of freedom. The Ind-PyC2 and Ind-PyC3 hybrids displayed some antioxidant activity when tested at 750 µg/mL (up to 95% inhibition of DPPH radical scavenging for 10). In both series, most hybrids were also able to interact with amyloid fibers, even if the inhibitory effect was observed at a high 100 µM concentration. The Ind-PyC0 molecules stand out completely due to their spectroscopic properties which prevent their evaluation by Ellman’s and ThT assays. However, these molecules showed interesting features in the presence of preformed fibers. In particular, the strong increase in fluorescence of 3 in the presence of amyloid fibers is very promising for its use as a fibrillation fluorescent reporter dye.

Effect of Gene Editing on Alzheimer's Disease

Abstract Background Alzheimer’s disease is an irreversible, progressive brain disorder that slowly destroys memory and thinking skills, and, eventually, the ability to carry out the simplest tasks. In most people with Alzheimer’s, symptoms first appear in their mid-60s. Current estimates suggest that 44 million people live with dementia worldwide at present. This is predicted to more than triple by 2050 as the population ages. Alzheimer’s disease is currently ranked as the sixth leading cause of death in the United States, but recent estimates indicate that the disorder may rank third, just behind heart disease and cancer, as a cause of death for older people Treatment is currently targeted toward symptomatic therapy, although trials are underway that aim to reduce the production and overall burden of pathology within the brain. Recently, the Clustered Regular Interspaced Short Palindromic Repeats (CRISPR-cas9) has shown promise in certain neurological disorders, it provides a precise editing to human genome and reflect an efficient curative therapy. We aimed to investigate the efficacy of knock-out of the APP gene “Amyloid precursor protein gene(APBA2)that consequently modify the expression of Amyloid protein in leucocytes cell line using CRISPR-cas9 technology. Methods The gene expression profile of Alzheimer's disease was downloaded from biological bioinformatics databases,and based on bioinformatics analysis, we figured out that APP gene was overexpressed in Alzheimer's disease in both brain and peripheral tissues such as plasma, fibroblast and PMNLs. We used PMNLs as the source of gene for edition in our study .We knocked out the APP gene in leucocytes cell lines using CRISPR-cas9 technology. Finally, the gene editing efficacy was evaluated by cell viability assay, the gene expression was measured by qPCR and the Amyloid protein expression was proved by Immunofluorescence. Results knockout of APP gene int Leucocytes Cell line resulted in reduction in cell viability that was associated with marked reduction in the amyloid protein and gene expressions. Conclusion knockout of APP(APBA2) gene represents a promising therapeutic strategy in Alzheimer's disease.

Abstract P103: Association Of Lipid Variability With Incident Alzheimers Disease And Alzheimers Disease Related Dementias

Background: Prevention strategies for Alzheimer’s disease and Alzheimer’s disease related dementias (AD/ADRDs) are urgently needed for reducing incidence. Intra-patient variability in lipid levels is a potentially modifiable risk factor for incident AD/ADRD. Although regular lipid measurements are a part of common clinical practice and longitudinal data routinely available in electronic health records (EHR), research examining this association between AD/ADRD and lipid variability across multiple lipid types remains scarce. Methods: All residents living in Olmsted County, MN on 1/1/2006 age ≥60 years without an AD/ADRD diagnosis were identified using Centers for Medicare & Medicaid Services diagnostic codes. Persons with ≥3 lipid measurements (total cholesterol or triglycerides) in the 5 years prior to index date were retained. Lipid variability was quantified using variability independent of the mean (VIM). Models were adjusted for traditional risk factors. Associations between lipid variability quintiles and incident AD/ADRD were assessed using Cox proportional hazards regression. Multiple imputation was used for missing covariates. Participants were followed through 2018 for incident AD/ADRD. Results: The final analysis included data on 11,551 participants with total cholesterol and 11,502 participants with triglycerides. Participants had a mean age of 71 (range 60-99) years, and were primarily white (96%). Females (54%) were also slightly more frequent than males. Median follow up was 12.9 years (range: 0-13). Participants in the highest quintile of variability for total cholesterol and triglycerides had a 20% increased risk of incident AD/ADRD. Similar results were found in the subset with complete covariate data. Conclusion: In a large EHR derived cohort, persons in the highest quintile of lipid variation had an increased risk of incident AD/ADRD. Further studies to identify the mechanisms behind this risk factor and replication of these results across a more diverse population are needed.

Use of Zebrafish Genetic Models to Study Etiology of the Amyloid-Beta and Neurofibrillary Tangle Pathways in Alzheimer's Disease.

The prevalence of neurodegenerative diseases is increasing globally, with an imperative need to identify and expand the availability of pharmaceutical treatment strategies. Alzheimer's disease is the most common neurodegenerative disease for which there is no cure and limited treatments. Rodent models are primarily used in Alzheimer's disease research to investigate causes, pathology, molecular mechanisms, and pharmaceutical therapies. However, there is a lack of a comprehensive understanding of Alzheimer's disease causes, pathogenesis, and optimal treatments due in part to some limitations of using rodents, including higher economic cost, which can influence sample size and ultimately statistical power. It is necessary to expand our animal model toolbox to provide alternative strategies in Alzheimer's disease research. The zebrafish application in neurodegenerative disease research and neuropharmacology is greatly expanding due to several vital strengths spanning lower economic costs, the smaller size of the organism, a sequenced characterized genome, and well described anatomical structures. These characteristics are coupled to the conserved molecular function and disease pathways in humans. The existence of orthologs for genes associated with Alzheimer's disease in zebrafish is also confirmed. While wild-type zebrafish appear to lack some of the neuropathological features of Alzheimer's disease, the advent of genetic editing technologies has expanded the evaluation of the amyloid and neurofibrillary tangle hypotheses using the zebrafish and exploration of pharmaceutical molecular targets. An overview of how genetic editing technologies are being used on the zebrafish to create models to investigate the causes, pathology, molecular mechanisms, and pharmaceutical targets of Alzheimer's disease is detailed.

Photo-oxygenation by a biocompatible catalyst reduces amyloid-β levels in Alzheimer's disease mice.

Amyloid formation and the deposition of the amyloid-β peptide are hallmarks of Alzheimer's disease pathogenesis. Immunotherapies using anti-amyloid-β antibodies have been highlighted as a promising approach for the prevention and treatment of Alzheimer's disease by enhancing microglial clearance of amyloid-β peptide. However, the efficiency of antibody delivery into the brain is limited, and therefore an alternative strategy to facilitate the clearance of brain amyloid is needed. We previously developed an artificial photo-oxygenation system using a low molecular weight catalytic compound. The photocatalyst specifically attached oxygen atoms to amyloids upon irradiation with light, and successfully reduced the neurotoxicity of aggregated amyloid-β via inhibition of amyloid formation. However, the therapeutic effect and mode of actions of the photo-oxygenation system in vivo remained unclear. In this study, we demonstrate that photo-oxygenation facilitates the clearance of aggregated amyloid-β from the brains of living Alzheimer's disease model mice, and enhances the microglial degradation of amyloid-β peptide. These results suggest that photo-oxygenation may represent a novel anti-amyloid-β strategy in Alzheimer's disease, which is compatible with immunotherapy.

β-Carboline as a Privileged Scaffold for Multitarget Strategies in Alzheimer's Disease Therapy.

The natural β-carboline alkaloids display similarities with neurotransmitters that can be favorably exploited to design bioactive and bioavailable drugs for Alzheimer's disease (AD) therapy. Several AD targets are currently and intensively being investigated, divided in different hypotheses: mainly the cholinergic, the amyloid β (Aβ), and the Tau hypotheses. To date, only symptomatic treatments are available involving acetylcholinesterase and NMDA inhibitors. On the basis of plethoric single-target structure-activity relationship studies, the β-carboline scaffold was identified as a powerful tool for fostering activity and molecular interactions with a wide range of AD-related targets. This knowledge can undoubtedly be used to design multitarget-directed ligands, a highly relevant strategy preferred in the context of multifactorial pathology with intricate etiology such as AD. In this review, we first individually discuss the AD targets of the β-carbolines, and then we focus on the multitarget strategies dedicated to the deliberate design of new efficient scaffolds.

Diagnostic and therapeutic potential of exosomal miRNAs in Alzheimer's disease.

Diagnostic and therapeutic potential of exosomal miRNAs in Alzheimer's disease.

Selective Targeting of Non-nuclear Estrogen Receptors with PaPE-1 as a New Treatment Strategy for Alzheimer\u2019s Disease

Alzheimer’s disease (AD) is a multifactorial and severe neurodegenerative disorder characterized by progressive memory decline, the presence of Aβ plaques and tau tangles, brain atrophy, and neuronal loss. Available therapies provide moderate symptomatic relief but do not alter disease progression. This study demonstrated that PaPE-1, which has been designed to selectively activate non-nuclear estrogen receptors (ERs), has anti-AD capacity, as evidenced in a cellular model of the disease. In this model, the treatment of mouse neocortical neurons with Aβ (5 and 10 μM) induced apoptosis (loss of mitochondrial membrane potential, activation of caspase-3, induction of apoptosis-related genes and proteins) accompanied by increases in levels of reactive oxygen species (ROS) and lactate dehydrogenase (LDH) as well as reduced cell viability. Following 24 h of exposure, PaPE-1 inhibited Aβ-evoked effects, as shown by reduced parameters of neurotoxicity, oxidative stress, and apoptosis. Because PaPE-1 downregulated Aβ-induced Fas/FAS expression but upregulated that of Aβ-induced FasL, the role of PaPE-1 in controlling the external apoptotic pathway is controversial. However, PaPE-1 normalized Aβ-induced loss of mitochondrial membrane potential and restored the BAX/BCL2 ratio, suggesting that the anti-AD capacity of PaPE-1 particularly relies on inhibition of the mitochondrial apoptotic pathway. These data provide new evidence for an anti-AD strategy that utilizes the selective targeting of non-nuclear ERs with PaPE-1.

CHRFAM7A: A human specific fusion gene, accounts for the translational gap for cholinergic strategies in Alzheimer's disease.

BackgroundCholinergic neuronal loss is one of the hallmarks of AD related neurodegeneration; however, preclinical promise of α7 nAChR drugs failed to translate into humans. CHRFAM7A, a uniquely human fusion gene, is a negative regulator of α7 nAChR and was unaccounted for in preclinical models.MethodsMolecular methods: Function of CHRFAM7A alleles was studied in vitro in two disease relevant phenotypic readouts: electrophysiology and Aβ uptake. Genome edited human induced pluripotent stem cells (iPSC) were used as a model system with the human context. Double blind pharmacogenetic study: We performed double-blind pharmacogenetic analysis on the effect of AChEI therapy based on CHRFAM7A carrier status in two paradigms: response to drug initiation and DMT effect. Mini Mental Status Examination (MMSE) was used as outcome measure. Change in MMSE score from baseline was compared by 2-tailed T-test. Longitudinal analysis of clinical outcome (MMSE) was performed using a fitted general linear model, based on an assumed autoregressive covariance structure. Model independent variables included age, sex, and medication regimen at the time of the first utilized outcome measure (AChEI alone or AChEI plus memantine), APOE4 carrier status (0, 1 or 2 alleles as categorical variables) and CHRFAM7A genotype.FindingsThe direct and inverted alleles have distinct phenotypes. Functional CHRFAM7A allele classifies the population as 25% non-carriers and 75% carriers. Induced pluripotent stem cell (iPSC) models α7 nAChR mediated Aβ neurotoxicity. Pharmacological readout translates into both first exposure (p = 0.037) and disease modifying effect (p = 0.0048) in two double blind pharmacogenetic studies.InterpretationCHRFAM7A accounts for the translational gap in cholinergic strategies in AD. Clinical trials not accounting for this uniquely human genetic factor may have rejected drug candidates that would benefit 25% of AD. Reanalyses of the completed trials using this pharmacogenetic paradigm may identify effective therapy.Funding:

Identification and Nanomechanical Characterization of the HIV Tat-Amyloid β Peptide Multifibrillar Structures.

HIV transactivator of transcription (Tat) protein could interact with amyloid β (Aβ) peptide which cause the growth of Aβ plaques in the brain and result in Alzheimer's disease in HIV-infected patients. Herein, we employ high-resolution atomic force microscopy and quantitative nanomechanical mapping to investigate the effects of Tat protein in Aβ peptide aggregation. Our results demonstrate that the Tat protein could bind to the Aβ fibril surfaces and result in the formation of Tat-Aβ multifibrillar structures. The resultant Tat-Aβ multifibrillar aggregates represent an increase in stiffness compared with Aβ fibrils due to the increase in β-sheet formation. The identification and characterization of the Tat-Aβ intermediate aggregates is important to understanding the interactions between Tat protein and Aβ peptide, and the development of novel therapeutic strategy for Alzheimer's disease-like disorder in HIV infected individuals.

Preventive and Therapeutic Strategies in Alzheimer's Disease: Focus on Oxidative Stress, Redox Metals, and Ferroptosis.

Significance: Alzheimer's disease (AD) is the most common cause of dementia in the elderly. AD is currently ranked as the sixth leading cause of death, but some sources put it as third, after heart disease and cancer. Currently, there are no effective therapeutic approaches to treat or slow the progression of chronic neurodegeneration. In addition to the accumulation of amyloid-β (Aβ) and tau, AD patients show progressive neuronal loss and neuronal death, also high oxidative stress that correlates with abnormal levels or overload of brain metals. Recent Advances: Several promising compounds targeting oxidative stress, redox metals, and neuronal death are under preclinical or clinical evaluation as an alternative or complementary therapeutic strategy in mild cognitive impairment and AD. Here, we present a general analysis and overview, discuss limitations, and suggest potential directions for these treatments for AD and related dementia. Critical Issues: Most of the disease-modifying therapeutic strategies for AD under evaluation in clinical trials have focused on components of the amyloid cascade, including antibodies to reduce levels of Aβ and tau, as well as inhibitors of secretases. Unfortunately, several of the amyloid-focused therapeutics have failed the clinical outcomes or presented side effects, and numerous clinical trials of compounds have been halted, reducing realistic options for the development of effective AD treatments. Future Directions: The focus of research on AD and related dementias is shifting to alternative or innovative areas, such as ApoE, lipids, synapses, oxidative stress, cell death mechanisms, neuroimmunology, and neuroinflammation, as well as brain metabolism and bioenergetics.

Targeting Infectious Agents as a Therapeutic Strategy in Alzheimer's Disease.

Alzheimer's disease (AD) is the most prevalent dementia in the world. Its cause(s) are presently largely unknown. The most common explanation for AD, now, is the amyloid cascade hypothesis, which states that the cause of AD is senile plaque formation by the amyloid β peptide, and the formation of neurofibrillary tangles by hyperphosphorylated tau. A second, burgeoning theory by which to explain AD is based on the infection hypothesis. Much experimental and epidemiological data support the involvement of infections in the development of dementia. According to this mechanism, the infection either directly or via microbial virulence factors precedes the formation of amyloid β plaques. The amyloid β peptide, possessing antimicrobial properties, may be beneficial at an early stage of AD, but becomes detrimental with the progression of the disease, concomitantly with alterations to the innate immune system at both the peripheral and central levels. Infection results in neuroinflammation, leading to, and sustained by, systemic inflammation, causing eventual neurodegeneration, and the senescence of the immune cells. The sources of AD-involved microbes are various body microbiome communities from the gut, mouth, nose, and skin. The infection hypothesis of AD opens a vista to new therapeutic approaches, either by treating the infection itself or modulating the immune system, its senescence, or the body's metabolism, either separately, in parallel, or in a multi-step way.

Positive allosteric activation of glial EAAT-2 transporter protein: A novel strategy for Alzheimer’s disease

Excitatory amino acid transporter-2 (EAAT-2) protein localized in the membrane of glial cells are responsible for the clearance of glutamate in synapse and it plays a key role among the five glutamate transporters (EAATs) in regulating synaptic transmission and preventing excitotoxicity in neurons. EAAT-2 dysfunction has been associated with the neuropathology of Alzheimer’s disease (AD). Impairment of EAAT-2 transporter function results excess accumulation of glutamate in synaptic cleft that acts on post-synaptic glutaminergic receptors excessively resulting in influx of Na+ and Ca2+ ions into the neurons. This triggers excitotoxicity in post-synaptic neurons by activating apoptotic or necrotic pathways causing neurodegeneration in AD. The compounds that increase the EAAT-2 activity may have therapeutic potential for neuroprotection in AD. The positive allosteric site activation of EAAT-2 represents a promising entry point for the identification of novel pharmacological compounds for the management of neurodegenerative conditions involving glutamate-mediated excitotoxicity. We hypothesize, therefore, that the positive allosteric activators may enhance glutamate clearance from the synaptic cleft by promoting orthosteric binding of glutamate ligand in EAAT-2 transporter protein and attenuate the excitotoxicity in neurons and prevent the disease progression of AD.

Treatment of Alzheimer's disease with framework nucleic acids.

ObjectivesTo provide a new research direction for nerve regeneration and strategy for Alzheimer's disease treatment, tetrahedral DNA nanostructures (TDNs)—novel tetrahedral framework nucleic acid molecule nanoparticles (tFNA) that can inhibit the apoptosis of nerve cells are employed in the experiment.Materials and methodsTo verify the successful preparation of TDNs, the morphology of TDNs was observed by atomic force microscopy (AFM) and transmission electron microscopy (TEM). The expression of apoptosis‐related genes and proteins was investigated by confocal microscope, flow cytometry, PCR and Western blot to detect the impact of TDNs on the Alzheimer's model. And finally, Morris water maze experiment was used to test behavioural changes and Nissl stain was detected to observe the morphology and quantity of neurons in the hippocampus. Immunofluorescence stain was used to observe the Aβ stain, and TUNEL dyeing was utilized to observe neuronal apoptosis.ResultsIn vitro and in vivo experiments confirm that TDNs, in a specific concentration range, have no toxic or side effects on nerve cells, can effectively inhibit apoptosis in an Alzheimer's disease cell model and effectively improve memory and learning ability in a rat model of Alzheimer's disease.ConclusionsThese findings suggest that TDNs may be a promising drug for the treatment of Alzheimer's disease.

Riluzole: a therapeutic strategy in Alzheimer’s disease by targeting the WNT/β-catenin pathway

Alzheimer’s disease (AD) is a neurodegenerative disease, where the etiology remains unclear. AD is characterized by amyloid-(Aβ) protein aggregation and neurofibrillary plaques deposits. Oxidative stress and chronic inflammation have been suggested as causes of AD. Glutamatergic pathway dysregulation is also mainly associated with AD process. In AD, the canonical WNT/β-catenin pathway is downregulated. Downregulation of WNT/β-catenin, by activation of GSK-3β-induced Aβ, and inactivation of PI3K/Akt pathway involve oxidative stress in AD. The downregulation of the WNT/β-catenin pathway decreases the activity of EAAT2, the glutamate receptors, and leads to neuronal death. In AD, oxidative stress, neuroinflammation and glutamatergic pathway operate in a vicious circle driven by the dysregulation of the WNT/β-catenin pathway. Riluzole is a glutamate modulator and used as treatment in amyotrophic lateral sclerosis. Recent findings have highlighted its use in AD and its potential increase power on the WNT pathway. Nevertheless, the mechanism by which Riluzole can operate in AD remains unclear and should be better determine. The focus of our review is to highlight the potential action of Riluzole in AD by targeting the canonical WNT/β-catenin pathway to modulate glutamatergic pathway, oxidative stress and neuroinflammation

Role of repetitive transcranial magnetic stimulation in management of alzheimer's disease

Management strategies in Alzheimer's disease (AD) are challenging and limited in several aspects. Repetitive transcranial magnetic stimulation (rTMS), being a noninvasive brain stimulation method, has recently been studied in the management of AD. The literature available is different on several aspects such as patient enrollment, site of stimulation, outcome measures, and follow-up. We present a narrative review highlighting important aspects of rTMS in AD. We searched the databases of Google Scholar and PubMed using the search terms: rTMS and Alzheimer's disease; rTMS and cognition; rTMS and dementia; and brain stimulation and Alzheimer's disease. Original research, case reports and series, other narrative reviews, systematic reviews, and meta-analyses were included, and studies where only abstracts were available were excluded. Majority of the studies present a modest benefit of rTMS in mild–moderate AD and some in normal aging and mild cognitive impairment. Improvement is marked in high-frequency rTMS as compared to low frequency. The favorite site of stimulation appears to be the dorsolateral prefrontal cortex (DLPFC). Studies chiefly assessed cognitive function, while sparingly involving other areas of impairment such as psychopathology and global functioning. Improvement in cognition is mainly in the weeks ensuring rTMS, and studies assessing improvement in a long-term follow-up are needed. There appears to be minimal to no side effects reported in most studies. Future implications of rTMS in AD are suggested.