Reduced insulin signaling maintains electrical transmission in a neural circuit in aging flies.

Lowered insulin/insulin-like growth factor (IGF) signaling (IIS) can extend healthy lifespan in worms, flies, and mice, but it can also have adverse effects (the "insulin paradox"). Chronic, moderately lowered IIS rescues age-related decline in neurotransmission through the Drosophila giant fiber system (GFS), a simple escape response neuronal circuit, by increasing targeting of the gap junctional protein innexin shaking-B to gap junctions (GJs). Endosomal recycling of GJs was also stimulated in cultured human cells when IIS was reduced. Furthermore, increasing the activity of the recycling small guanosine triphosphatases (GTPases) Rab4 or Rab11 was sufficient to maintain GJs upon elevated IIS in cultured human cells and in flies, and to rescue age-related loss of GJs and of GFS function. Lowered IIS thus elevates endosomal recycling of GJs in neurons and other cell types, pointing to a cellular mechanism for therapeutic intervention into aging-related neuronal disorders.

Optimized peripheral blood progenitor cell mobilization for autologous hematopoietic cell transplantation in children with high-risk and refractory malignancies.

BACKGROUND: Autologous hematopoietic stem cell transplantation (aHSCT) using hematopoietic progenitor cells (HPCs) has become an important therapeutic modality for patients with high-risk malignancies. Current literature on standardized method for HPC apheresis in children is sparse and failure rate reported as high as 30%. PATIENTS/METHODS: A retrospective study of 125 pediatric patients with high-risk malignancies undergoing aHSCT in Western Australia between 1997 and 2016 was conducted. RESULTS: Mobilization was achieved by means of chemotherapy and granulocyte colony-stimulating factor (G-CSF). Patients underwent apheresis the day after CD34+ counts reached ≥20/µL and an additional dose of G-CSF. Peripheral arterial and intravenous lines were inserted in pediatric intensive care unit under local anesthetic and/or sedation, omitting the need for general anesthesia as well as facilitating an uninterrupted apheresis flow. Larger apheresis total blood volumes were processed in patients weighing ≤20 kg. The minimal dose of ≥2 × 106 CD34+ cells/kg was successfully collected in 98.4% of all patients. The optimal dose of 3-5 × 106 CD34+ cells/kg was collected in 96% of patients scheduled for a single aHSCT, 87.5% for tandem, and 100% for triple aHSCT. All HPC collections were completed in one apheresis session. Mobilization after ≤3 chemotherapy cycles and cycles including cyclophosphamide resulted in a significantly higher yield of CD34+ cells. CONCLUSION: Our approach to HPC mobilization by means of chemotherapy and single myeloid growth factor combined with optimal collection timing facilitated by continuous apheresis flow resulted in highly effective HPC harvest in children and adolescents with high-risk cancers.

Direct Keap1-Nrf2 disruption as a potential therapeutic target for Alzheimer's disease.

Nrf2, a transcriptional activator of cell protection genes, is an attractive therapeutic target for the prevention of neurodegenerative diseases, including Alzheimer's disease (AD). Current Nrf2 activators, however, may exert toxicity and pathway over-activation can induce detrimental effects. An understanding of the mechanisms mediating Nrf2 inhibition in neurodegenerative conditions may therefore direct the design of drugs targeted for the prevention of these diseases with minimal side-effects. Our study provides the first in vivo evidence that specific inhibition of Keap1, a negative regulator of Nrf2, can prevent neuronal toxicity in response to the AD-initiating Aß42 peptide, in correlation with Nrf2 activation. Comparatively, lithium, an inhibitor of the Nrf2 suppressor GSK-3, prevented Aß42 toxicity by mechanisms independent of Nrf2. A new direct inhibitor of the Keap1-Nrf2 binding domain also prevented synaptotoxicity mediated by naturally-derived Aß oligomers in mouse cortical neurons. Overall, our findings highlight Keap1 specifically as an efficient target for the re-activation of Nrf2 in AD, and support the further investigation of direct Keap1 inhibitors for the prevention of neurodegeneration in vivo.

Vaccine-preventable disease following allogeneic haematopoietic stem cell transplant in Western Australia.

AIM: Infection is an important and frequent cause of mortality and morbidity following allogeneic haematopoietic stem cell transplantation (HSCT). This study was conducted to determine the epidemiology and clinical phenotype of vaccine-preventable disease in children who have undergone HSCT following the implementation of a standard revaccination programme. METHODS: Children receiving first allogeneic HSCT in Western Australia between January 2005 and December 2014 were eligible for recruitment. Patients received standard antimicrobial prophylaxis and were vaccinated according to the West Australian post-HSCT immunisation schedule, commencing 6 months following HSCT. Children who developed any illness post-HSCT were reviewed, and investigations for infectious disease were undertaken as clinically indicated. Positive identification of vaccine-preventable disease was documented with the clinical course of the illness. RESULTS: A total of 71 patients were enrolled in the study. The overall incidence of vaccine-preventable disease following HSCT was 19.7%; influenza accounted for 50% of all cases, herpes zoster for 42.9%. All episodes occurred late, beyond day 100 post-HSCT. Overall survival for matched-sibling donor transplants was 83.3 and 75.0% at 1 and 5 years, respectively, and was 72.3 and 63.3% for alternative donor transplants. Mortality due to vaccine-preventable disease was low, with one death from disseminated herpes zoster. CONCLUSIONS: There is a high incidence of vaccine-preventable morbidity post-allogeneic HSCT in West Australian children. Viral aetiology constitutes the main burden, namely, influenza infection and varicella zoster virus reactivation. Further efforts are required to identify the most appropriate preventative strategies.

A holidic medium for Drosophila melanogaster.

A critical requirement for research using model organisms is a well-defined and consistent diet. There is currently no complete chemically defined (holidic) diet available for Drosophila melanogaster. We describe a holidic medium that is equal in performance to an oligidic diet optimized for adult fecundity and lifespan. This holidic diet supports development over multiple generations but at a reduced rate. Over 7 years of experiments, the holidic diet yielded more consistent experimental outcomes than did oligidic food for egg laying by females. Nutrients and drugs were more available to flies in holidic medium and, similar to dietary restriction on oligidic food, amino acid dilution increased fly lifespan. We used this holidic medium to investigate amino acid-specific effects on food-choice behavior and report that folic acid from the microbiota is sufficient for Drosophila development.

Inhibition of GSK-3 ameliorates Abeta pathology in an adult-onset Drosophila model of Alzheimer's disease.

Abeta peptide accumulation is thought to be the primary event in the pathogenesis of Alzheimer's disease (AD), with downstream neurotoxic effects including the hyperphosphorylation of tau protein. Glycogen synthase kinase-3 (GSK-3) is increasingly implicated as playing a pivotal role in this amyloid cascade. We have developed an adult-onset Drosophila model of AD, using an inducible gene expression system to express Arctic mutant Abeta42 specifically in adult neurons, to avoid developmental effects. Abeta42 accumulated with age in these flies and they displayed increased mortality together with progressive neuronal dysfunction, but in the apparent absence of neuronal loss. This fly model can thus be used to examine the role of events during adulthood and early AD aetiology. Expression of Abeta42 in adult neurons increased GSK-3 activity, and inhibition of GSK-3 (either genetically or pharmacologically by lithium treatment) rescued Abeta42 toxicity. Abeta42 pathogenesis was also reduced by removal of endogenous fly tau; but, within the limits of detection of available methods, tau phosphorylation did not appear to be altered in flies expressing Abeta42. The GSK-3-mediated effects on Abeta42 toxicity appear to be at least in part mediated by tau-independent mechanisms, because the protective effect of lithium alone was greater than that of the removal of tau alone. Finally, Abeta42 levels were reduced upon GSK-3 inhibition, pointing to a direct role of GSK-3 in the regulation of Abeta42 peptide level, in the absence of APP processing. Our study points to the need both to identify the mechanisms by which GSK-3 modulates Abeta42 levels in the fly and to determine if similar mechanisms are present in mammals, and it supports the potential therapeutic use of GSK-3 inhibitors in AD.

Creating connections: developing an online space for cross-regional mentorship and network building in the dementia research field.

Background: Effective development and retention of talented early-career researchers (ECRs) is essential to the continued success of biomedical science research fields. To this end, formal mentorship programmes (where researchers are paired with one or more mentors beyond their direct manager) have proven to be successful in providing support and expanding career development opportunities. However, many programmes are limited to pools of mentors and mentees within one institute or geographical area, highlighting that cross-regional connections may be a missed opportunity in many mentorship schemes. Methods: Here, we aimed to address this limitation through our pilot cross-regional mentorship scheme, creating reciprocal mentor-mentee pairings between two pre-established networks of Alzheimer's Research UK (ARUK) Network-associated researchers. We carefully created 21 mentor-mentee pairings between the Scotland and University College London (UCL) networks in 2021, with surveys conducted to assess mentor/mentee satisfaction with the programme. Results: Participants reported very high satisfaction with the nature of the pairings and the mentors' contribution to the career development of mentees; a majority also reported that the mentorship scheme increased their connections outside of their home network. Our assessment of this pilot programme is that it supports the utility of cross-regional mentorship schemes for ECR development. At the same time, we highlight the limitations of our programme and recommend areas for improvement in future programmes, including greater consideration of support for minoritized groups and the need for additional training for mentors. Conclusions: In conclusion, our pilot scheme generated successful and novel mentor-mentee pairings across pre-existing networks; both of which reported high satisfaction with pairings, ECR career and personal development, and the formation of new cross-network connections. This pilot may serve as a model for other networks of biomedical researchers, where existing networks within medical research charities can act as a scaffold to build new cross-regional career development opportunities for researchers.

Activating transcription factor 4-dependent lactate dehydrogenase activation as a protective response to amyloid beta toxicity.

Accumulation of amyloid beta peptides is thought to initiate the pathogenesis of Alzheimer's disease. However, the precise mechanisms mediating their neurotoxicity are unclear. Our microarray analyses show that, in Drosophila models of amyloid beta 42 toxicity, genes involved in the unfolded protein response and metabolic processes are upregulated in brain. Comparison with the brain transcriptome of early-stage Alzheimer's patients revealed a common transcriptional signature, but with generally opposing directions of gene expression changes between flies and humans. Among these differentially regulated genes, lactate dehydrogenase (Ldh) was up-regulated by the greatest degree in amyloid beta 42 flies and the human orthologues (LDHA and LDHB) were down-regulated in patients. Functional analyses revealed that either over-expression or inhibition of Ldh by RNA interference (RNAi) slightly exacerbated climbing defects in both healthy and amyloid beta 42-induced Drosophila. This suggests that metabolic responses to lactate dehydrogenase must be finely-tuned, and that its observed upregulation following amyloid beta 42 production could potentially represent a compensatory protection to maintain pathway homeostasis in this model, with further manipulation leading to detrimental effects. The increased Ldh expression in amyloid beta 42 flies was regulated partially by unfolded protein response signalling, as ATF4 RNAi diminished the transcriptional response and enhanced amyloid beta 42-induced climbing phenotypes. Further functional studies are required to determine whether Ldh upregulation provides compensatory neuroprotection against amyloid beta 42-induced loss of activating transcription factor 4 activity and endoplasmatic reticulum stress. Our study thus reveals dysregulation of lactate dehydrogenase signalling in Drosophila models and patients with Alzheimer's disease, which may lead to a detrimental loss of metabolic homeostasis. Importantly, we observed that down-regulation of ATF4-dependent endoplasmic reticulum-stress signalling in this context appears to prevent Ldh compensation and to exacerbate amyloid beta 42-dependent neuronal toxicity. Our findings, therefore, suggest caution in the use of therapeutic strategies focussed on down-regulation of this pathway for the treatment of Alzheimer's disease, since its natural response to the toxic peptide may induce beneficial neuroprotective effects.

Dynamic changes in the brain protein interaction network correlates with progression of Aß42 pathology in Drosophila.

Alzheimer's disease (AD), the most prevalent form of dementia, is a progressive and devastating neurodegenerative condition for which there are no effective treatments. Understanding the molecular pathology of AD during disease progression may identify new ways to reduce neuronal damage. Here, we present a longitudinal study tracking dynamic proteomic alterations in the brains of an inducible Drosophila melanogaster model of AD expressing the Arctic mutant Aß42 gene. We identified 3093 proteins from flies that were induced to express Aß42 and age-matched healthy controls using label-free quantitative ion-mobility data independent analysis mass spectrometry. Of these, 228 proteins were significantly altered by Aß42 accumulation and were enriched for AD-associated processes. Network analyses further revealed that these proteins have distinct hub and bottleneck properties in the brain protein interaction network, suggesting that several may have significant effects on brain function. Our unbiased analysis provides useful insights into the key processes governing the progression of amyloid toxicity and forms a basis for further functional analyses in model organisms and translation to mammalian systems.

Immunogenicity of the inactivated influenza vaccine in children who have undergone allogeneic haematopoietic stem cell transplant.

Influenza vaccination is recommended for children following allogeneic haematopoietic stem cell transplant (HSCT), however there is limited evidence regarding its benefit. A prospective multicentre study was conducted to evaluate the immunogenicity of the inactivated influenza vaccine in children who have undergone HSCT compared with healthy age-matched controls. Participants were vaccinated between 2013 and 2016 according to Australian guidelines. Influenza-specific hemagglutinin inhibition antibody titres were performed prior to each vaccination and 4 weeks following the final vaccination. A nasopharyngeal aspirate for influenza was performed on participants that developed influenza-like illness. There were 86 children recruited; 43 who had undergone HSCT and 43 controls. For the HSCT group, seroprotection and seroconversion rates were 81.4% and 60.5% for H3N2, 41.9% and 32.6% for H1N1, and 44.2% and 39.5% for B strain respectively. There was a significant geometric mean fold increase to the H3N2 (GMFI 5.80, 95% CI 3.68-9.14, p < 0.001) and B (GMFI 3.44, 95% CI 2.36-5.00, p = 0.048) strains. Serological response was superior in age-matched controls to all vaccine strains. There were no serious adverse events following vaccination. For children who underwent HSCT, incidence of laboratory-proven influenza infection was 2.3%. Overall, this study provides evidence to support annual inactivated influenza vaccine administration to children following HSCT.

Deletion of Irs2 reduces amyloid deposition and rescues behavioural deficits in APP transgenic mice.

As impaired insulin signalling (IIS) is a risk factor for Alzheimer's disease we crossed mice (Tg2576) over-expressing human amyloid precursor protein (APP), with insulin receptor substrate 2 null (Irs2(-/-)) mice which develop insulin resistance. The resulting Tg2576/Irs2(-/-) animals had increased tau phosphorylation but a paradoxical amelioration of Abeta pathology. An increase of the Abeta binding protein transthyretin suggests that increased clearance of Abeta underlies the reduction in plaques. Increased tau phosphorylation correlated with reduced tau-phosphatase PP2A, despite an inhibition of the tau-kinase glycogen synthase kinase-3. Our findings demonstrate that disruption of IIS in Tg2576 mice has divergent effects on pathological processes-a reduction in aggregated Abeta but an increase in tau phosphorylation. However, as these effects are accompanied by improvement in behavioural deficits, our findings suggest a novel protective effect of disrupting IRS2 signalling in AD which may be a useful therapeutic strategy for this condition.

Neurophysiology of human touch and eye gaze in therapeutic relationships and healing: a scoping review.

OBJECTIVE: The primary objective of this scoping review was to examine and map the range of neurophysiological impacts of human touch and eye gaze, and consider their potential relevance to the therapeutic relationship and to healing. INTRODUCTION: Clinicians, and many patients and their relatives, have no doubt as to the efficacy of a positive therapeutic relationship; however, much evidence is based on self-reporting by the patient or observation by the researcher. There has been little formal exploration into what is happening in the body to elicit efficacious reactions in patients. There is, however, a growing body of work on the neurophysiological impact of human interaction. Physical touch and face-to-face interaction are two central elements of this interaction that produce neurophysiological effects on the body. INCLUSION CRITERIA: This scoping review considered studies that included cognitively intact human subjects in any setting. This review investigated the neurophysiology of human interaction including touch and eye gaze. It considered studies that have examined, in a variety of settings, the neurophysiological impacts of touch and eye gaze. Quantitative studies were included as the aim was to examine objective measures of neurophysiological changes as a result of human touch and gaze. METHODS: An extensive search of multiple databases was undertaken to identify published research in the English language with no date restriction. Data extraction was undertaken using an extraction tool developed specifically for the scoping review objectives. RESULTS: The results of the review are presented in narrative form supported by tables and concept maps. Sixty-four studies were included and the majority were related to touch with various types of massage predominating. Only seven studies investigated gaze with three of these utilizing both touch and gaze. Interventions were delivered by a variety of providers including nurses, significant others and masseuses. The main neurophysiological measures were cortisol, oxytocin and noradrenaline. CONCLUSIONS: The aim of this review was to map the neurophysiological impact of human touch and gaze. Although our interest was in studies that might have implications for the therapeutic relationship, we accepted studies that explored phenomena outside of the context of a nurse-patient relationship. This allowed exploration of the boundary of what might be relevant in any therapeutic relationship. Indeed, only a small number of studies included in the review involved clinicians (all nurses) and patients. There was sufficient consistency in trends evident across many studies in regard to the beneficial impact of touch and eye gaze to warrant further investigation in the clinical setting. There is a balance between tightly controlled studies conducted in an artificial (laboratory) setting and/or using artificial stimuli and those of a more pragmatic nature that are contextually closer to the reality of providing nursing care. The latter should be encouraged.

Molecular Mechanisms of Lithium Action: Switching the Light on Multiple Targets for Dementia Using Animal Models.

Lithium has long been used for the treatment of psychiatric disorders, due to its robust beneficial effect as a mood stabilizing drug. Lithium's effectiveness for improving neurological function is therefore well-described, stimulating the investigation of its potential use in several neurodegenerative conditions including Alzheimer's (AD), Parkinson's (PD) and Huntington's (HD) diseases. A narrow therapeutic window for these effects, however, has led to concerted efforts to understand the molecular mechanisms of lithium action in the brain, in order to develop more selective treatments that harness its neuroprotective potential whilst limiting contraindications. Animal models have proven pivotal in these studies, with lithium displaying advantageous effects on behavior across species, including worms (C. elegans), zebrafish (Danio rerio), fruit flies (Drosophila melanogaster) and rodents. Due to their susceptibility to genetic manipulation, functional genomic analyses in these model organisms have provided evidence for the main molecular determinants of lithium action, including inhibition of inositol monophosphatase (IMPA) and glycogen synthase kinase-3 (GSK-3). Accumulating pre-clinical evidence has indeed provided a basis for research into the therapeutic use of lithium for the treatment of dementia, an area of medical priority due to its increasing global impact and lack of disease-modifying drugs. Although lithium has been extensively described to prevent AD-associated amyloid and tau pathologies, this review article will focus on generic mechanisms by which lithium preserves neuronal function and improves memory in animal models of dementia. Of these, evidence from worms, flies and mice points to GSK-3 as the most robust mediator of lithium's neuro-protective effect, but it's interaction with downstream pathways, including Wnt/ß-catenin, CREB/brain-derived neurotrophic factor (BDNF), nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and toll-like receptor 4 (TLR4)/nuclear factor-κB (NFκB), have identified multiple targets for development of drugs which harness lithium's neurogenic, cytoprotective, synaptic maintenance, anti-oxidant, anti-inflammatory and protein homeostasis properties, in addition to more potent and selective GSK-3 inhibitors. Lithium, therefore, has advantages as a multi-functional therapy to combat the complex molecular pathology of dementia. Animal studies will be vital, however, for comparative analyses to determine which of these defense mechanisms are most required to slow-down cognitive decline in dementia, and whether combination therapies can synergize systems to exploit lithium's neuro-protective power while avoiding deleterious toxicity.

PTEN, a negative regulator of PI3 kinase signalling, alters tau phosphorylation in cells by mechanisms independent of GSK-3.

Deregulation of PTEN/Akt signalling has been recently implicated in the pathogenesis of Alzheimer's disease (AD), but the effects on the molecular processes underlying AD pathology have not yet been fully described. Here we report that overexpression of PTEN reduces tau phosphorylation in CHO cells. This effect was abrogated by mutant PTEN constructs with either a catalytically inactive point mutation (C124S) or with only inactive lipid phosphatase activity (G129E), suggesting an indirect, lipid phosphatase-dependent process. The predominant effects of PTEN on tau appeared to be mediated by reducing ERK1/2 activity, but were independent of Akt, GSK-3, JNK and the tau phosphatases PP1 and PP2A. Our studies provide evidence for an effect of PTEN on the phosphorylation of tau in AD pathogenesis, and provide some insight into the mechanisms through which deregulation of PTEN may contribute towards the progression of tauopathy.

The neurophysiology of human touch and eye gaze and its effects on therapeutic relationships and healing: a scoping review protocol.

REVIEW QUESTION/OBJECTIVE: The objective of this scoping review is to examine and map the range of neurophysiological impacts of human touch and eye gaze, and better understand their possible links to the therapeutic relationship and the process of healing. The specific question is "what neurophysiological impacts of human touch and eye gaze have been reported in relation to therapeutic relationships and healing?"

Deletion of endogenous Tau proteins is not detrimental in Drosophila.

Human Tau (hTau) is a highly soluble and natively unfolded protein that binds to microtubules within neurons. Its dysfunction and aggregation into insoluble paired helical filaments is involved in the pathogenesis of Alzheimer's disease (AD), constituting, together with accumulated ß-amyloid (Aß) peptides, a hallmark of the disease. Deciphering both the loss-of-function and toxic gain-of-function of hTau proteins is crucial to further understand the mechanisms leading to neurodegeneration in AD. As the fruit fly Drosophila melanogaster expresses Tau proteins (dTau) that are homologous to hTau, we aimed to better comprehend dTau functions by generating a specific tau knock-out (KO) fly line using homologous recombination. We observed that the specific removal of endogenous dTau proteins did not lead to overt, macroscopic phenotypes in flies. Indeed, survival, climbing ability and neuronal function were unchanged in tau KO flies. In addition, we did not find any overt positive or negative effect of dTau removal on human Aß-induced toxicity. Altogether, our results indicate that the absence of dTau proteins has no major functional impact on flies, and suggests that our tau KO strain is a relevant model to further investigate the role of dTau proteins in vivo, thereby giving additional insights into hTau functions.

Increased Glucose Transport into Neurons Rescues Aß Toxicity in Drosophila.

Glucose hypometabolism is a prominent feature of the brains of patients with Alzheimer's disease (AD). Disease progression is associated with a reduction in glucose transporters in both neurons and endothelial cells of the blood-brain barrier. However, whether increasing glucose transport into either of these cell types offers therapeutic potential remains unknown. Using an adult-onset Drosophila model of Aß (amyloid beta) toxicity, we show that genetic overexpression of a glucose transporter, specifically in neurons, rescues lifespan, behavioral phenotypes, and neuronal morphology. This amelioration of Aß toxicity is associated with a reduction in the protein levels of the unfolded protein response (UPR) negative master regulator Grp78 and an increase in the UPR. We further demonstrate that genetic downregulation of Grp78 activity also protects against Aß toxicity, confirming a causal effect of its alteration on AD-related pathology. Metformin, a drug that stimulates glucose uptake in cells, mimicked these effects, with a concomitant reduction in Grp78 levels and rescue of the shortened lifespan and climbing defects of Aß-expressing flies. Our findings demonstrate a protective effect of increased neuronal uptake of glucose against Aß toxicity and highlight Grp78 as a novel therapeutic target for the treatment of AD.

Lithium Promotes Longevity through GSK3/NRF2-Dependent Hormesis.

The quest to extend healthspan via pharmacological means is becoming increasingly urgent, both from a health and economic perspective. Here we show that lithium, a drug approved for human use, promotes longevity and healthspan. We demonstrate that lithium extends lifespan in female and male Drosophila, when administered throughout adulthood or only later in life. The life-extending mechanism involves the inhibition of glycogen synthase kinase-3 (GSK-3) and activation of the transcription factor nuclear factor erythroid 2-related factor (NRF-2). Combining genetic loss of the NRF-2 repressor Kelch-like ECH-associated protein 1 (Keap1) with lithium treatment revealed that high levels of NRF-2 activation conferred stress resistance, while low levels additionally promoted longevity. The discovery of GSK-3 as a therapeutic target for aging will likely lead to more effective treatments that can modulate mammalian aging and further improve health in later life.

Glycogen synthase kinase-3 is increased in white cells early in Alzheimer's disease.

Alzheimer's disease (AD) is a disorder without a molecular marker in peripheral tissues or a disease modifying treatment. As increasing evidence has suggested a role for glycogen synthase kinase-3 (GSK-3) in the pathogenesis of the condition we measured total GSK-3 protein (alpha and beta isoforms) and GSK-3 activity (serine 9 phosphorylation) in a group of healthy elderly people, in AD and in mild cognitive impairment (MCI). Total GSK-3 protein was increased in both AD and in MCI without a compensatory decrease in activity. These data suggest that GSK-3 assays might be a useful diagnostic marker in a readily available tissue and moreover that GSK-3 activity is increased in the prodromal phase of the disorder suggesting that inhibition of GSK-3 might be a useful therapeutic strategy.