A Novel Peptidome Technology for the Diagnosis of Mild Cognitive Impairment and Alzheimer's Disease by Selected Reaction Monitoring.

Background: With the aging of populations worldwide, Alzheimer's disease (AD) has become a concern due to its high prevalence and the continued lack of established treatments. Early diagnosis is required as a preventive intervention to modify the disease's progression. In our previous study, we performed peptidomic analysis of serum samples obtained from AD patients and age-matched healthy subjects to seek peptide biomarker candidates for AD by using BLOTCHIP-MS analysis, and identified four peptides as AD biomarker candidates. Objective: The objective was to validate the serum biomarker peptides to distinguish mild cognitive impairment (MCI) and AD in comparison to cognitively healthy controls using a new peptidome technology, the Dementia Risk Test. Methods: We enrolled 195 subjects with normal cognitive function (NC; n = 70), MCI (n = 55), and AD (n = 70), The concentrations of cognitive impairment marker peptides (Fibrinogen α chain (FAC), Fibrinogen ß chain (FBC), Plasma protease C1 inhibitor (PPC1I), α2-HS-glycoprotein (AHSG)) were quantified by using a selected reaction monitoring assay based on liquid chromatography-MS/MS. Results: The present study confirmed that three peptides, FAC, FBC, and PPC1I, were significantly upregulated during the onset of AD. This three-peptide set was both highly sensitive in determining AD (sensitivity: 85.7%, specificity: 95.7%, AUC: 0.900) and useful in distinguishing MCI (sensitivity: 61.8%, specificity: 98.6%, AUC: 0.824) from NC. Conclusions: In this validation study, we confirmed the high diagnostic potential of the three peptides identified in our previous study as candidate serum biomarkers for AD. The Dementia Risk Test may be a powerful tool for detecting AD-related pathological changes.

Protective effect of scallop-derived plasmalogen against vascular dysfunction, via the pSTAT3/PIM1/NFATc1 axis, in a novel mouse model of Alzheimer's disease with cerebral hypoperfusion.

A strong relationship between Alzheimer's disease (AD) and vascular dysfunction has been the focus of increasing attention in aging societies. In the present study, we examined the long-term effect of scallop-derived plasmalogen (sPlas) on vascular remodeling-related proteins in the brain of an AD with cerebral hypoperfusion (HP) mouse model. We demonstrated, for the first time, that cerebral HP activated the axis of the receptor for advanced glycation endproducts (RAGE)/phosphorylated signal transducer and activator of transcription 3 (pSTAT3)/provirus integration site for Moloney murine leukemia virus 1 (PIM1)/nuclear factor of activated T cells 1 (NFATc1), accounting for such cerebral vascular remodeling. Moreover, we also found that cerebral HP accelerated pSTAT3-mediated astrogliosis and activation of the nucleotide-binding domain and leucine-rich repeat protein 3 (NLRP3) inflammasome, probably leading to cognitive decline. On the other hand, sPlas treatment attenuated the activation of the pSTAT3/PIM1/NFATc1 axis independent of RAGE and significantly suppressed NLRP3 inflammasome activation, demonstrating the beneficial effect on AD.

Neuroprotective effect of, a flavonoid, sudachitin in mice stroke model.

A flavonoid, sudachitin, has been reported to show some beneficial health effects, including as an anti-inflammatory in LPS-stimulated macrophages, as well as improving glucose and lipid metabolism in mice fed a high-fat diet. In this study, we investigated the neuroprotective effect of sudachitin in the transient middle cerebral artery occlusion (tMCAO) mouse model. After daily pre-treatment of vehicle or sudachitin (5 or 50 mg/kg) for 14 days, mice (n = 76) were subjected to a sham operation or tMCAO for 45 min, and on the following days, they were treated daily with vehicle or sudachitin. The administration of sudachitin significantly reduced (p < 0.05) cerebral infarct volume and attenuated apoptosis, 5 days after tMCAO. Neurological impairment improved, the expression of an oxidative stress marker, 4-HNE, decreased, and the Sirt1/PGC-1α pathway was activated 5 days after tMCAO in the sudachitin-treated group. This is the first report to demonstrate the neuroprotective effect of sudachitin in cerebral ischemia/reperfusion injury mice model, probably by activating the Sirt1/PGC-1α axis. Sudachitin may be a promising supplement or therapeutic agent for reducing injury caused by ischemic strokes.

Protective Effects of Rivaroxaban on White Matter Integrity and Remyelination in a Mouse Model of Alzheimer's Disease Combined with Cerebral Hypoperfusion.

BACKGROUND: Alzheimer's disease (AD) is characterized by cognitive dysfunction and memory loss that is accompanied by pathological changes to white matter. Some clinical and animal research revealed that AD combined with chronic cerebral hypoperfusion (CCH) exacerbates AD progression by inducing blood-brain barrier dysfunction and fibrinogen deposition. Rivaroxaban, an anticoagulant, has been shown to reduce the rates of dementia in atrial fibrillation patients, but its effects on white matter and the underlying mechanisms are unclear. OBJECTIVE: The main purpose of this study was to explore the therapeutic effect of rivaroxaban on the white matter of AD+CCH mice. METHODS: In this study, the therapeutic effects of rivaroxaban on white matter in a mouse AD+CCH model were investigated to explore the potential mechanisms involving fibrinogen deposition, inflammation, and oxidative stress on remyelination in white matter. RESULTS: The results indicate that rivaroxaban significantly attenuated fibrinogen deposition, fibrinogen-related microglia activation, oxidative stress, and enhanced demyelination in AD+CCH mice, leading to improved white matter integrity, reduced axonal damage, and restored myelin loss. CONCLUSIONS: These findings suggest that long-term administration of rivaroxaban might reduce the risk of dementia.

Injection of exogenous amyloid-ß oligomers aggravated cognitive deficits, and activated necroptosis, in APP23 transgenic mice.

Alzheimer's disease (AD) is a neurodegenerative disease that is characterized by the loss of synapses and neurons in the brain, and the accumulation of amyloid plaques. Aß oligomers (AßO) play a critical role in the pathogenesis of AD. Although there is increasing evidence to support the involvement of necroptosis in the pathogenesis of AD, the exact mechanism remains elusive. In the present study, we explored the effect of exogenous AßO injection on cell necroptosis and cognitive deficits in APP23 transgenic mice. We found that intrahippocampal injection of AßO accelerated the development of AD pathology and caused cognitive impairment in APP23 mice. Specifically, AßO injection significantly accelerated the accumulation of AßO and increased the expression level of phosphorylated-tau, and also induced necroptosis. Behavioral tests showed that AßO injection was associated with cognitive impairment. Furthermore, necroptosis induced by AßO injection occurred predominantly in microglia of the AD brain. We speculate that AßO increased necroptosis by activating microglia, resulting in cognitive deficits. Our results may aid in an understanding of the role played by AßO in AD from an alternative perspective and provide new ideas and evidence for necroptosis as a potential intervention and therapeutic target for AD.

Human Cord Blood-Endothelial Progenitor Cells Alleviate Intimal Hyperplasia of Arterial Damage in a Rat Stroke Model.

Human cord blood-endothelial progenitor cells (hCB-EPCs) isolated from the human umbilical cord can be used to repair damaged arteries. In this study, we used an animal model with pathological changes that mimics artery wall damage caused by stent retrievers in humans. We injected hCB-EPCs to investigate their effect on endothelial hyperplasia and dysfunction during intimal repair. Four groups were established based on the length of reperfusion (3 and 28 days), as well as the presence or absence of hCB-EPC therapy. Damage to the internal carotid artery was evaluated by hematoxylin-eosin and immunohistochemical staining. Stroke volume was not significantly different between non-EPC and EPC groups although EPC treatment alleviated intimal hyperplasia 28 days after intimal damage. Vascular endothelial growth factor (VEGF) and eNOS expression were significantly higher in the EPC-treated group than in the non-EPC group 3 days after intimal damage. In addition, MMP9 and 4HNE expression in the EPC-treated group was significantly lower than in the non-EPC group. Ultimately, this study found that venous transplantation of hCB-EPCs could inhibit neointimal hyperplasia, alleviate endothelial dysfunction, suppress intimal inflammation, and reduce oxidative stress during healing of intimal damage.

Neuroprotective effects of carnosine in a mice stroke model concerning oxidative stress and inflammatory response.

Carnosine (ß-alanyl-L-histidine) is a natural dipeptide with multiple neuroprotective properties. Previous studies have advertised that carnosine scavenges free radicals and displays anti-inflammatory activity. However, the underlying mechanism and the efficacies of its pleiotropic effect on prevention remained obscure. In this study, we aimed to investigate the anti-oxidative, anti-inflammative, and anti-pyroptotic effects of carnosine in the transient middle cerebral artery occlusion (tMCAO) mouse model. After a daily pre-treatment of saline or carnosine (1000 mg / kg / day) for 14 days, mice (n = 24) were subjected to tMCAO for 60 min and continuously treated with saline or carnosine for additional 1 and 5 days after reperfusion. The administration of carnosine significantly decreased infarct volume 5 days after the tMCAO (*p < 0.05) and effectively suppressed the expression of 4-HNE, 8-OHdG, Nitrotyrosine 5 days, and RAGE 5 days after tMCAO. Moreover, the expression of IL-1ß was also significantly suppressed 5 days after tMCAO. Our present findings demonstrated that carnosine effectively relieves oxidative stress caused by ischemic stroke and significantly attenuates neuroinflammatory responses related to IL-1ß, suggesting that carnosine can be a promising therapeutic strategy for ischemic stroke.

A young female case of asymptomatic immune-mediated necrotizing myopathy: a potential diagnostic option of antibody testing for rhabdomyolysis.

Anti-3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) immune-mediated necrotizing myopathy (IMNM) is a neuromuscular disorder that presents muscle weakness in proximal extremities and/or the trunk with an elevation of creatine kinase (CK). Young and asymptomatic anti-HMGCR IMNM patients are very rare and a treatment regimen has not been established. The present case, a 17-year-old woman without any muscular symptoms, only showed hyperCKemia that was detected by chance. After close examinations, including a muscle biopsy and antibody search, she was diagnosed as anti-HMGCR IMNM, and initial treatment with methotrexate and continuous intravenous immunoglobulin seemed to be effective. The present case is the unusually young asymptomatic case of anti-HMGCR IMNM. The diagnosis was successfully made, leading to the early introduction of a treatment. Given the course of this case, we believe that the preceding antibody testing is one of the diagnostic option for rhabdomyolysis.

Actual Telemedicine Needs of Japanese Patients with Neurological Disorders in the COVID-19 Pandemic.

Objective During the coronavirus disease 2019 (COVID-19) pandemic, many social activities have moved online using applications for digital devices (e.g. computers, smartphones). We investigated the needs of telemedicine and trends in medical status and social care situations of Japanese patients with neurological disorders in order to estimate their affinity for an online telemedicine application. Methods We designed an original questionnaire for the present study that asked participants what problems they had with hospital visits, how the COVID-19 pandemic had affected their lives, and whether or not they would like to receive telemedicine. Patients The present study included volunteer caregivers, participants with Parkinson's disease (PD), epilepsy, stroke, dementia, immune-mediated neurological disease (IMMD), spinocerebellar degeneration (SCD), amyotrophic lateral sclerosis (ALS), headache, myopathy, and other neurological diseases from Okayama University Hospital. Results A total of 29.6% of patients wanted to use telemedicine. Patients with headaches (60.0%) and epilepsy (38.1%) were more likely to want to use telemedicine than patients with PD (17.8%) or stroke (19.0%). Almost 90% of patients had access to a digital device, and there was no association between favoring telemedicine, ownership of a digital device, hospital visiting time, or waiting time at the hospital, although age was associated with motivation to telemedicine use (52.6 vs. 62.2 years old, p<0.001). Conclusion We can contribute to the management of the COVID-19 pandemic and the medical economy by promoting telemedicine, especially for young patients with headaches or epilepsy.

Tocovid Attenuated Oxidative Stress and Cognitive Decline by Inhibiting Amyloid-ß-Induced NOX2 Activation in Alzheimer's Disease Mice.

BACKGROUND: NADPH oxidase 2 (NOX2) is an important source of reactive oxygen species (ROS). Activated NOX2 may contribute to Alzheimer's disease (AD). Our previous studies showed that a novel vitamin E mixture, Tocovid, had potential neuroprotective effects in a stroke mice model and an AD cell model. OBJECTIVE: The aim of this study was two-fold: to assess whether long-term Tocovid treatment can regulate NOX2, and the therapeutic effects of long-term administration of Tocovid to an AD mice model. METHODS: Therapeutic effects of long-term administration of Tocovid (200 mg/kg /day) on an Aß-overexpressed transgenic AD mice model (APP23, n = 8) was investigated. The therapeutic effect of Tocovid in 16-month-old mice compared with the no-treatment APP23 group (n = 9) was assessed. RESULTS: Tocovid treatment strongly improved motor and memory deficits of APP23 mice by attenuating NOX2 expression, oxidative stress, neuroinflammation, neurovascular unit dysfunction, synaptic alteration, and Aß deposition after 16 months. CONCLUSION: These findings suggest that NOX2 is a potential target in AD pathology. Long-term administration of Tocovid may be a promising candidate for AD treatment.

Clinical and Pathological Benefits of Scallop-Derived Plasmalogen in a Novel Mouse Model of Alzheimer's Disease with Chronic Cerebral Hypoperfusion.

BACKGROUND: The oral ingestion of scallop-derived plasmalogen (sPlas) significantly improved cognitive function in Alzheimer's disease (AD) patients. OBJECTIVE: However, the effects and mechanisms of sPlas on AD with chronic cerebral hypoperfusion (CCH), a class of mixed dementia contributing to 20-30% among the dementia society, were still elusive. METHODS: In the present study, we applied a novel mouse model of AD with CCH to investigate the potential effects of sPlas on AD with CCH. RESULTS: The present study demonstrated that sPlas significantly recovered cerebral blood flow, improved motor and cognitive deficits, reduced amyloid-ß pathology, regulated neuroinflammation, ameliorated neural oxidative stress, and inhibited neuronal loss in AD with CCH mice at 12 M. CONCLUSION: These findings suggest that sPlas possesses clinical and pathological benefits for AD with CCH in the novel model mice. Furthermore, sPlas could have promising prevention and therapeutic effects on patients of AD with CCH.

Efficacy and safety of spot heating and ultrasound irradiation on in vitro and in vivo thrombolysis models.

The feasibility of transcranial sonothrombolysis has been demonstrated, although little is known about the relationships between thermal or mechanical mechanisms and thrombolytic outcomes. Therefore, the present study aims to reveal the effect and safety of temperature and ultrasound through in vitro and in vivo thrombolysis models. Artificial clots in microtubes were heated in a water bath or sonicated by ultrasound irradiation, and then clots weight decrease with rising temperature and sonication time was confirmed. In the in vitro thrombotic occlusion model, based on spot heating, clot volume was reduced and clots moved to the distal side, followed by recanalization of the occlusion. In the in vivo study, the common carotid artery of rats was exposed to a spot heater or to sonication. No brain infarct or brain blood barrier disruption was shown, but endothelial junctional dysintegrity and an inflammatory response in the carotid artery were detected. The present spot heating and ultrasound irradiation models seem to be effective for disintegrating clots in vitro, but the safety of the in vivo model was not fully supported by the data. However, the data indicates that a shorter time exposure could be less invasive than a longer exposure.

Protective Effect of Rivaroxaban Against Amyloid Pathology and Neuroinflammation Through Inhibiting PAR-1 and PAR-2 in Alzheimer's Disease Mice.

BACKGROUND: Recent studies have revealed that atrial fibrillation (AF) patients have a high risk of developing cognitive impairment, vascular dementia, and Alzheimer's disease (AD). Some reports suggest that the application of oral anticoagulant with an appropriate dose may have a preventive effect on AD. However, which oral anticoagulant drug is more appropriate for preventing AD and the underlying mechanism(s) is still unknown. OBJECTIVE: The aim of the present study was to assess the treatment effect of rivaroxaban administration as well as investigate the roles of PAR-1 and PAR-2 in the AD + CAA mice model. METHODS: In the present study, we compared a traditional oral anticoagulant, warfarin, and a direct oral anticoagulant (DOAC), rivaroxaban, via long-term administration to an AD with cerebral amyloid angiopathy (CAA) mice model. RESULTS: Rivaroxaban treatment attenuated neuroinflammation, blood-brain barrier dysfunction, memory deficits, and amyloid-ß deposition through PAR-1/PAR-2 inhibition in the AD + CAA mice model compared with warfarin and no-treatment groups. CONCLUSION: The present study demonstrates that rivaroxaban can attenuate AD progress and can be a potential choice to prevent AD.

Early detection of cognitive decline in mild cognitive impairment and Alzheimer's disease with a novel eye tracking test.

Due to an increasing number of dementia patients, the development of a rapid and sensitive method for cognitive assessment is awaited. Here, we examined the usefulness of a novel and short (3 min) eye tracking device to evaluate the cognitive function of normal control (NC, n = 52), mild cognitive impairment (MCI, n = 52), and Alzheimer's disease (AD, n = 70) subjects. Eye tracking total score declined significantly in MCI (**p < 0.01 vs NC) and AD (**p < 0.01 vs NC, ##p < 0.01 vs MCI), and correlated well with the mini-mental state examination (MMSE) score (r = 0.57, *p < 0.05). Furthermore, the eye tracking test, especially memory and deductive reasoning tasks, effectively discriminated NC, MCI and AD. The present novel eye tracking test clearly discriminated cognitive functions among NC, MCI, and AD subjects, thereby providing an advantage for the early detection of MCI and AD in screening.

Neuroprotective effects of Scallop-derived plasmalogen in a mouse model of ischemic stroke.

Scallop-derived plasmalogen (sPlas) has both anti-oxidative and anti-inflammation activities, but its efficacy has not been investigated in ischemic stroke models where oxidative stress, inflammation, and neurovascular unit (NVU) damage accelerates pathophysiological progression. Therefore, in the present study, we aimed to assess the neuroprotective effects of sPlas in ischemic stroke by using a transient middle cerebral artery occlusion (tMCAO) mouse model. After the pretreatment of vehicle or sPlas (10 mg/kg/day) for 14 days, adult male mice were subjected to tMCAO for 60 min, then continuously treated with vehicle or sPlas during reperfusion and for an additional 5 days. The administration of sPlas significantly improved motor deficits (corner and rotarod tests, *p < 0.05 vs vehicle), enhanced serum antioxidative activity (OXY-adsorbent and d-ROMs tests, *p < 0.05 vs vehicle), reduced infarction volume (*p < 0.05 vs vehicle), decreased the expression of two oxidative stress markers, 4-HNE (*p < 0.05 vs vehicle) and 8-OHdG (*p < 0.05 vs vehicle), decreased the expression of pro-inflammatory markers Iba-1 (**p < 0.01 vs vehicle), IL-1ß (**p < 0.01 vs vehicle), and TNF-α (**p < 0.01 vs vehicle), and alleviated NVU damage (collagen IV, MMP9, and GFAP/collagen IV, *p < 0.05 vs vehicle). Our present findings are the first to demonstrate the neuroprotective effects of sPlas on acute ischemic stroke mice at 5 d after tMCAO via anti-oxidative stress, anti-inflammation, and improvement of NVU damage, suggesting the potential of sPlas in preventing and treating ischemic stroke.

Hypoxic stress visualized in the cervical spinal cord of ALS patients.

Objective: Amyotrophic lateral sclerosis (ALS) is a progressive and fatal motor neuron disease. Hypoxic stress is suspected as the pathogenesis of ALS, however, no positron emission tomography (PET) study for hypoxic stress has been conducted in the spinal cord of ALS patients.Methods: In the present study, we examined cervical spinal hypoxic stress of nineALS patients with upper extremity (U/E) atrophy by18F-fluoromisonidazole (FMISO) PET.Results: On the ipsilateral side of C1 and C5 levels, 18F-FMISO uptake increased significantly compared with the contralateral side (*p < 0.05) and the control subject (**p < 0.01). In addition, a strong correlation was found between 18F-FMISO uptake of the C5 level and the rate of progression of the ALS FRS-R score (R = 0.781, *p = 0.013).Conclusion: These results indicate that hypoxic stress increased in the spinal cord of ALS patients with a close link to ALS progression. Both hypoxic stress and a compromised response to hypoxia, which may lead to subsequent motor neuron death, could be a potential therapeutic target for ALS.

Bone Marrow Stromal Cell Transplantation Drives Molecular Switch from Autophagy to the Ubiquitin-Proteasome System in Ischemic Stroke Mice.

BACKGROUND: Bone marrow stromal cell (BMSC) transplantation is a promising therapeutic approach for cerebral ischemia, as it elicits multiple neuroprotective effects. However, it remains unclear how BMSC transplantation modulates the ubiquitin-proteasome system (UPS) and autophagy under cerebral ischemia. METHODS: In the present study, an intermediate level of cerebral ischemia (30 minutes) was chosen to examine the effect of BMSC transplantation on the molecular switch regulating UPS and autophagy. BMSC or vehicle was stereotactically injected into the penumbra 15 minutes after sham operation or transient middle cerebral artery occlusion (tMCAO). RESULTS: Thirty minutes of tMCAO artery occlusion significantly increased TUNEL-, ubiquitin-, and p62-positive cells (which peaked at 72 hours, 2 hours, and 2 hours after reperfusion, respectively) and ratios of both BAG3/BAG1 and LC3-II/LC3-I at 24 hours after reperfusion. However, intracerebral injection of BMSCs significantly reduced infarct volume and numbers of TUNEL- and p62-positive cells, and improved BAG3/BAG1 and LC3-II/LC3-I ratios. In addition, observed increases in ubiquitin-positive cells 2 hours after reperfusion were slightly suppressed by BMSC transplantation. CONCLUSIONS: These data suggest a protective role of BMSC transplantation, which drove the molecular switch from autophagy to UPS in a murine model of ischemic stroke.

Effects of exoskeletal gait assistance on the recovery motion following tripping.

Physical assistant robots improve the user's ability to walk. However, they also potentially affect recovery motion following tripping. The assist algorithm should not interfere with the recovery motion, and should enhance the ability of the user to recover after tripping. Thus, in this study, we investigated the recovery motion affected by the assist robot after tripping. We compared the recovery motion with different reaction algorithms. Principal component analysis revealed the effects of the reaction algorithm. Correspondingly, principal components were related to the recovery motion during two steps following tripping. Specifically, the effects of the reaction algorithm were related to a principal component that represented the motion of the second step after tripping and that increased the margin of stability. Furthermore, the margin of stability became significantly large when the assistive torque was applied during the recovery motion. The result of this study suggests that the assist robot can potentially enhances the recovery motion of its user following tripping.

Yoga-plus exercise mix promotes cognitive, affective, and physical functions in elderly people.

Objectives: Increased attention is being paid to Asian medicine in balanced total health care. We investigated the effects of mixed exercise including yoga ('Yoga-plus') among elderly individuals. Methods: A total of 385 subjects (72 males and 313 females, 75.5 ± 8.7 years old) participated in a 12-month (M) exercise program at a health and welfare center, a day service center, and a nursing home. Cognitive, affective, and physical functions, and activities of daily living (ADL), were compared at baseline (0M), 6M and 12M of exercise intervention. Results: Mean scores on the frontal assessment battery, clock drawing test, cube copying test, letter fluency, and category fluency significantly improved after the Yoga-plus intervention, while mini-mental state examination, Hasegawa dementia score-revised, and trail-making test performance were relatively stable. Affective scores on the geriatric depression scale (GDS), apathy scale (AS) and Abe's behavioral and psychological symptoms of dementia were not significantly affected by exercise therapy, but subgroups with higher baseline GDS (GDS ≥ 5) and AS (AS ≥ 16) scores showed a significant improvement after intervention. One-leg standing time and 3-m timed up and go test performance significantly improved after 12M intervention. Discussion: Yoga-plus improved cognitive, affective, ADL, and physical functions in a local elderly population, particularly among below-baseline individuals, indicating the benefits of dementia prevention among elderly individuals.

Serine Phosphorylation of IRS1 Correlates with Aß-Unrelated Memory Deficits and Elevation in Aß Level Prior to the Onset of Memory Decline in AD.

The biological effects of insulin signaling are regulated by the phosphorylation of insulin receptor substrate 1 (IRS1) at serine (Ser) residues. In the brain, phosphorylation of IRS1 at specific Ser sites increases in patients with Alzheimer's disease (AD) and its animal models. However, whether the activation of Ser sites on neural IRS1 is related to any type of memory decline remains unclear. Here, we show the modifications of IRS1 through its phosphorylation at etiology-specific Ser sites in various animal models of memory decline, such as diabetic, aged, and amyloid precursor protein (APP) knock-in NL-G-F (APPKINL-G-F) mice. Substantial phosphorylation of IRS1 at specific Ser sites occurs in type 2 diabetes- or age-related memory deficits independently of amyloid-ß (Aß). Furthermore, we present the first evidence that, in APPKINL-G-F mice showing Aß42 elevation, the increased phosphorylation of IRS1 at multiple Ser sites occurs without memory impairment. Our findings suggest that the phosphorylation of IRS1 at specific Ser sites is a potential marker of Aß-unrelated memory deficits caused by type 2 diabetes and aging; however, in Aß-related memory decline, the modifications of IRS1 may be a marker of early detection of Aß42 elevation prior to the onset of memory decline in AD.