Antisense oligonucleotides targeting the miR-29b binding site in the GRN mRNA increase progranulin translation.

Heterozygous GRN (progranulin) mutations cause frontotemporal dementia (FTD) due to haploinsufficiency, and increasing progranulin levels is a major therapeutic goal. Several microRNAs, including miR-29b, negatively regulate progranulin protein levels. Antisense oligonucleotides (ASOs) are emerging as a promising therapeutic modality for neurological diseases, but strategies for increasing target protein levels are limited. Here, we tested the efficacy of ASOs as enhancers of progranulin expression by sterically blocking the miR-29b binding site in the 3' UTR of the human GRN mRNA. We found 16 ASOs that increase progranulin protein in a dose-dependent manner in neuroglioma cells. A subset of these ASOs also increased progranulin protein in iPSC-derived neurons and in a humanized GRN mouse model. In FRET-based assays, the ASOs effectively competed for miR-29b from binding to the GRN 3' UTR RNA. The ASOs increased levels of newly synthesized progranulin protein by increasing its translation, as revealed by polysome profiling. Together, our results demonstrate that ASOs can be used to effectively increase target protein levels by partially blocking miR binding sites. This ASO strategy may be therapeutically feasible for progranulin-deficient FTD as well as other conditions of haploinsufficiency.

Core requirements of frailty screening in the emergency department: an international Delphi consensus study.

INTRODUCTION: Frailty is associated with adverse outcomes among patients attending emergency departments (EDs). While multiple frailty screens are available, little is known about which variables are important to incorporate and how best to facilitate accurate, yet prompt ED screening. To understand the core requirements of frailty screening in ED, we conducted an international, modified, electronic two-round Delphi consensus study. METHODS: A two-round electronic Delphi involving 37 participants from 10 countries was undertaken. Statements were generated from a prior systematic review examining frailty screening instruments in ED (logistic, psychometric and clinimetric properties). Reflexive thematic analysis generated a list of 56 statements for Round 1 (August-September 2021). Four main themes identified were: (i) principles of frailty screening, (ii) practicalities and logistics, (iii) frailty domains and (iv) frailty risk factors. RESULTS: In Round 1, 13/56 statements (23%) were accepted. Following feedback, 22 new statements were created and 35 were re-circulated in Round 2 (October 2021). Of these, 19 (54%) were finally accepted. It was agreed that ideal frailty screens should be short (<5 min), multidimensional and well-calibrated across the spectrum of frailty, reflecting baseline status 2-4 weeks before presentation. Screening should ideally be routine, prompt (<4 h after arrival) and completed at first contact in ED. Functional ability, mobility, cognition, medication use and social factors were identified as the most important variables to include. CONCLUSIONS: Although a clear consensus was reached on important requirements of frailty screening in ED, and variables to include in an ideal screen, more research is required to operationalise screening in clinical practice.

Astrocytic K+ clearance during disease progression in amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder in which patients lose motor functions due to progressive loss of motor neurons in the cortex, brainstem, and spinal cord. Whilst the loss of neurons is central to the disease, it is becoming clear that glia, specifically astrocytes, contribute to the onset and progression of neurodegeneration. Astrocytes play an important role in maintaining ion homeostasis in the extracellular milieu and regulate multiple brain functions by altering their extracellular concentrations. In this study, we have investigated the ability of astrocytes to maintain K+ homeostasis in the brain via direct measurement of the astrocytic K+ clearance rate in the motor and somatosensory cortices of an ALS mouse model (SOD1G93A ). Using electrophysiological recordings from acute brain slices, we show region-specific alterations in the K+ clearance rate, which was significantly reduced in the primary motor cortex but not the somatosensory cortex. This decrease was accompanied by significant changes in astrocytic morphology, impaired conductivity via Kir4.1 channels and low coupling ratio in astrocytic networks in the motor cortex, which affected their ability to form the K+ gradient needed to disperse K+ through the astrocytic syncytium. These findings indicate that the supportive function astrocytes typically provide to motoneurons is diminished during disease progression and provides a potential explanation for the increased vulnerability of motoneurons in ALS.

Blood-brain barrier penetration of non-replicating SARS-CoV-2 and S1 variants of concern induce neuroinflammation which is accentuated in a mouse model of Alzheimer's disease.

COVID-19 and especially Long COVID are associated with severe CNS symptoms and may place persons at risk to develop long-term cognitive impairments. Here, we show that two non-infective models of SARS-CoV-2 can cross the blood-brain barrier (BBB) and induce neuroinflammation, a major mechanism underpinning CNS and cognitive impairments, even in the absence of productive infection. The viral models cross the BBB by the mechanism of adsorptive transcytosis with the sugar N-acetylglucosamine being key. The delta and omicron variants cross the BB B faster than the other variants of concern, with peripheral tissue uptake rates also differing for the variants. Neuroinflammation induced by icv injection of S1 protein was greatly enhanced in young and especially in aged SAMP8 mice, a model of Alzheimer's disease, whereas sex and obesity had little effect.

Sarcoplasmic reticulum calcium handling in unbranched, immediately post-necrotic fast-twitch mdx fibres is similar to wild-type littermates.

NEW FINDINGS: What is the central question of this study? What are the early effects of dystrophin deficiency on sarcoplasmic reticulum Ca2+ handling in the mdx mouse? What is the main finding and its importance? In the mdx mouse, Ca2+ handling by the sarcoplasmic reticulum is little affected by the absence of dystrophin when looking at fibres without branches that have recently regenerated after massive myonecrosis. This has important implications for our understanding of Ca2+ pathology in the mdx mouse. ABSTRACT: There is a variety of results in the literature regarding the effects of dystrophin deficiency on the Ca2+ handling properties of the sarcoplasmic reticulum (SR) in the mdx mouse, an animal model of Duchenne muscular dystrophy. One possible source of variation is the presence of branched fibres. Fibre branching, a consequence of degenerative-regenerative processes such as muscular dystrophy, has in itself a significant influence on the function of the SR. In this study, we attempted to detect early effects of dystrophin deficiency on SR Ca2+ handling by using unbranched fibres from the immediate post-necrotic stage in mdx mice (recently regenerated after massive necrosis). Using kinetically corrected fura-2 fluorescence signals measured during twitch and tetanus, we analysed the amplitude, rise time and decay time of Δ[Ca2+ ]i in unfatigued and fatigued fibres. Decay was also resolved into SR pump and SR leak components. Fibres from mdx mice were similar in all respects to fibres from wild-type littermates apart from: (1) a smaller amplitude of the initial spike of Δ[Ca2+ ]i during a tetanus; and (2) a mitigation of the fall in Δ[Ca2+ ]i amplitude during the course of fatigue. Our findings suggest that the early effects of a loss of dystrophin on SR Ca2+ handling in mdx mice are subtle, and we emphasize the importance of distinguishing between Ca2+ pathology that is attributable to lack of dystrophin and Ca2+ pathology that is attributable to muscle degeneration.

Healthcare for older adults in North America: challenges, successes and opportunities.

Older adults in North America face similar challenges to successful ageing as other adults around the world, including an increased risk of geriatric syndromes and functional decline, limited access to healthcare professionals specialising in geriatrics and constraints on healthcare spending for Long-Term Services and Supports. Geriatrics as a specialty has long been established, along with the creation of a variety of screening tools for early identification of geriatric syndromes. Despite this, workforce shortages in all older adult care service areas have led to significant gaps in care, particularly in community settings. To address these gaps, innovative programs that expand the reach of geriatric specialists and services have been developed. Opportunities exist for further dissemination of these programs and services, as well as for expansion of an ageing capable workforce.

Frailty in geriatric psychiatry inpatients: a retrospective cohort study.

OBJECTIVE: We aimed to evaluate the prevalence, clinical determinants, and consequences (falls and hospitalization) of frailty in older adults with mental illness. DESIGN: Retrospective clinical cohort study. SETTING: We collected the data in a specialized psychogeriatric ward, in Boston, USA, between July 2018 and June 2019. PARTICIPANTS: Two hundred and fourty-four inpatients aged 65 years old and over. MEASUREMENTS: Psychiatric diagnosis was based on a multi-professional consensus meeting according to DSM-5 criteria. Frailty was assessed according to two common instruments, that is, the FRAIL questionnaire and the deficit accumulation model (aka Frailty Index [FI]). Multiple linear regression analyses were conducted to evaluate the association between frailty and sample demographics (age, female sex, and non-Caucasian ethnicity) and clinical characteristics (dementia, number of clinical diseases, current infection, number of psychotropic, and non-psychotropic medications in use). Multiple regression between frailty assessments and either falls or number of hospital admissions in the last 6 and 12 months, respectively, were analyzed and adjusted for covariates. RESULTS: Prevalence of frailty was high, that is, 83.6% according to the FI and 55.3% according to the FRAIL questionnaire. Age, the number of clinical (somatic) diseases, and the number of non-psychotropic medications were independently associated with frailty identified by the FRAIL. Dementia, current infection, the number of clinical (somatic) diseases, and the number of non-psychotropic medications were independently associated with frailty according to the FI. Falls were significantly associated with both frailty instruments. However, we found only a significant association for the number of hospital admissions with the FI. CONCLUSION: Frailty is highly prevalent among geriatric psychiatry inpatients. The FRAIL questionnaire and the FI may capture different forms of frailty dimensions, being the former probably more associated with the phenotype model and the latter more associated with multimorbidity.

Dystrophin-negative slow-twitch soleus muscles are not susceptible to eccentric contraction induced injury over the lifespan of the mdx mouse.

Duchenne muscular dystrophy (DMD) is the second most common fatal genetic disease in humans and is characterized by the absence of a functional copy of the protein dystrophin from skeletal muscle. In dystrophin-negative humans and rodents, regenerated skeletal muscle fibers show abnormal branching. The number of fibers with branches and the complexity of branching increases with each cycle of degeneration/regeneration. Previously, using the mdx mouse model of DMD, we have proposed that once the number and complexity of branched fibers present in dystrophic fast-twitch EDL muscle surpasses a stable level, we term the "tipping point," the branches, in and of themselves, mechanically weaken the muscle by rupturing when subjected to high forces during eccentric contractions. Here, we use the slow-twitch soleus muscle from the dystrophic mdx mouse to study prediseased "periambulatory" dystrophy at 2-3 wk, the peak regenerative "adult" phase at 6-9 wk, and "old" at 58-112 wk. Using isolated mdx soleus muscles, we examined contractile function and response to eccentric contraction correlated with the amount and complexity of regenerated branched fibers. The intact muscle was enzymatically dispersed into individual fibers in order to count fiber branching and some muscles were optically cleared to allow laser scanning confocal microscopy. We demonstrate throughout the lifespan of the mdx mouse that dystrophic slow-twitch soleus muscle is no more susceptible to eccentric contraction-induced injury than age-matched littermate controls and that this is correlated with a reduction in the number and complexity of branched fibers compared with fast-twitch dystrophic EDL muscles.

Lowering dementia risk and slowing progression of disease: the role of cognitive reserve and cognitive training.

Almeida-Meza et al found an inverse correlation between cognitive reserve (associated with educational level, complexity of occupations and leisure activities) and dementia incidence. We suggest clarifying studies using their data-set and consider what can be done to modify socioeconomic inequalities that affect cognitive reserve or to slow early dementia.

The effect of a multicomponent exercise protocol (VIVIFRAIL©) on inflammatory profile and physical performance of older adults with different frailty status: study protocol for a randomized controlled trial.

BACKGROUND: To investigate whether an exercise intervention using the VIVIFRAIL© protocol has benefits for inflammatory and functional parameters in different frailty status. METHODS/DESIGN: This is a randomized clinical trial in an outpatient geriatrics clinic including older adults ≥60 years. For each frailty state (frail, pre-frail and robust), forty-four volunteers will be randomly allocated to the control group (n = 22) and the intervention group (n = 22) for 12 weeks. In the control group, participants will have meetings of health education while those in the intervention group will be part of a multicomponent exercise program (VIVIFRAIL©) performed five times a week (two times supervised and 3 times of home-based exercises). The primary outcome is a change in the inflammatory profile (a reduction in inflammatory interleukins [IL-6, TNF- α, IL1beta, IL-17, IL-22, CXCL-8, and IL-27] or an increase in anti-inflammatory mediators [IL-10, IL1RA, IL-4]). Secondary outcomes are change in physical performance using the Short Physical Performance Battery, handgrip strength, fatigue, gait speed, dual-task gait speed, depressive symptoms, FRAIL-BR and SARC-F scores, and quality of life at the 12-week period of intervention and after 3 months of follow-up. DISCUSSION: We expect a reduction in inflammatory interleukins or an increase in anti-inflammatory mediators in those who performed the VIVIFRAIL© protocol. The results of the study will imply in a better knowledge about the effect of a low-cost intervention that could be easily replicated in outpatient care for the prevention and treatment of frailty, especially regarding the inflammatory and anti-inflammatory pathways involved in its pathophysiology. TRIAL REGISTRATION: Brazilian Registry of Clinical Trials (RBR-9n5jbw; 01/24/2020). Registred January 2020. http://www.ensaiosclinicos.gov.br/rg/RBR-9n5jbw/ .

Smart Devices and Wearable Technologies to Detect and Monitor Mental Health Conditions and Stress: A Systematic Review.

Recently, there has been an increase in the production of devices to monitor mental health and stress as means for expediting detection, and subsequent management of these conditions. The objective of this review is to identify and critically appraise the most recent smart devices and wearable technologies used to identify depression, anxiety, and stress, and the physiological process(es) linked to their detection. The MEDLINE, CINAHL, Cochrane Central, and PsycINFO databases were used to identify studies which utilised smart devices and wearable technologies to detect or monitor anxiety, depression, or stress. The included articles that assessed stress and anxiety unanimously used heart rate variability (HRV) parameters for detection of anxiety and stress, with the latter better detected by HRV and electroencephalogram (EGG) together. Electrodermal activity was used in recent studies, with high accuracy for stress detection; however, with questionable reliability. Depression was found to be largely detected using specific EEG signatures; however, devices detecting depression using EEG are not currently available on the market. This systematic review highlights that average heart rate used by many commercially available smart devices is not as accurate in the detection of stress and anxiety compared with heart rate variability, electrodermal activity, and possibly respiratory rate.

Stress Watch: The Use of Heart Rate and Heart Rate Variability to Detect Stress: A Pilot Study Using Smart Watch Wearables.

Stress is an inherent part of the normal human experience. Although, for the most part, this stress response is advantageous, chronic, heightened, or inappropriate stress responses can have deleterious effects on the human body. It has been suggested that individuals who experience repeated or prolonged stress exhibit blunted biological stress responses when compared to the general population. Thus, when assessing whether a ubiquitous stress response exists, it is important to stratify based on resting levels in the absence of stress. Research has shown that stress that causes symptomatic responses requires early intervention in order to mitigate possible associated mental health decline and personal risks. Given this, real-time monitoring of stress may provide immediate biofeedback to the individual and allow for early self-intervention. This study aimed to determine if the change in heart rate variability could predict, in two different cohorts, the quality of response to acute stress when exposed to an acute stressor and, in turn, contribute to the development of a physiological algorithm for stress which could be utilized in future smartwatch technologies. This study also aimed to assess whether baseline stress levels may affect the changes seen in heart rate variability at baseline and following stress tasks. A total of 30 student doctor participants and 30 participants from the general population were recruited for the study. The Trier Stress Test was utilized to induce stress, with resting and stress phase ECGs recorded, as well as inter-second heart rate (recorded using a FitBit). Although the present study failed to identify ubiquitous patterns of HRV and HR changes during stress, it did identify novel changes in these parameters between resting and stress states. This study has shown that the utilization of HRV as a measure of stress should be calculated with consideration of resting (baseline) anxiety and stress states in order to ensure an accurate measure of the effects of additive acute stress.

Neuromodulation of Astrocytic K+ Clearance.

Potassium homeostasis is fundamental for brain function. Therefore, effective removal of excessive K+ from the synaptic cleft during neuronal activity is paramount. Astrocytes play a key role in K+ clearance from the extracellular milieu using various mechanisms, including uptake via Kir channels and the Na+-K+ ATPase, and spatial buffering through the astrocytic gap-junction coupled network. Recently we showed that alterations in the concentrations of extracellular potassium ([K+]o) or impairments of the astrocytic clearance mechanism affect the resonance and oscillatory behavior of both the individual and networks of neurons. These results indicate that astrocytes have the potential to modulate neuronal network activity, however, the cellular effectors that may affect the astrocytic K+ clearance process are still unknown. In this study, we have investigated the impact of neuromodulators, which are known to mediate changes in network oscillatory behavior, on the astrocytic clearance process. Our results suggest that while some neuromodulators (5-HT; NA) might affect astrocytic spatial buffering via gap-junctions, others (DA; Histamine) primarily affect the uptake mechanism via Kir channels. These results suggest that neuromodulators can affect network oscillatory activity through parallel activation of both neurons and astrocytes, establishing a synergistic mechanism to maximize the synchronous network activity.

Meaningful Engagement in the Nursing Home.

Throughout her career, Rosalie Kane made a major impact in her efforts to improve quality of life for persons living in nursing homes. Near the end of her career, she suggested that it was time to "re-imagine long term care and to produce livable age-friendly nursing homes." This brief review focuses on the role of meaningful engagement and person-centered care as the next step in enhancing nursing home care. The importance of activities that strengthen cognitive and/or physical function is stressed, as well as improving socialization to reduce loneliness.

Risk of incident dementia following metformin initiation compared with noninitiation or delay of antidiabetic medication therapy.

PURPOSE: Emerging evidence suggests metformin compared with sulfonylurea is associated with an 8% to 10% lower risk for dementia. Guidelines recommend metformin as initial diabetes treatment, but there is still the question of treatment timing. Thus, the risk of dementia associated with initiating metformin compared with not initiating or delaying treatment was examined. METHODS: A retrospective cohort study (1996 to 2015) was conducted with electronic health records from Veteran Health Affairs (VHA; n = 112 845) and Kaiser Permanente Washington (KPW; n = 14 333) healthcare systems. Patients were aged ≥50 years, had a hemoglobin A1c (HbA1c) between 6.5 and <9.5 mg/dL, and did not have dementia or fills for antidiabetic medications before cohort entry. Initiators started metformin monotherapy and noninitiators used no antidiabetic medications in the 6 months after the first qualifying HbA1c. The primary outcome was incident dementia. Propensity scores and inverse probability of treatment weighting (IPTW) controlled for confounding in Cox proportional hazards models. RESULTS: During a median follow-up of 6.2 years in VHA and 6.8 years in KPW, there were 7547 new dementia cases in VHA and 1090 in KPW. After IPTW, there was no association between initiation of metformin (vs no initial treatment) and incident dementia in VHA (HR = 1.04; 95% confidence interval [CI]: 0.95-1.13) or KPW (HR = 0.81; 95% CI: 0.51-1.28). Results did not differ by age, baseline HbA1c, or race. CONCLUSIONS: Results do not support initiating metformin earlier to prevent cognitive decline and, thus, may dampen enthusiasm for metformin as a potential antidementia drug. Randomized clinical trials could help clarify the relationship between metformin and cognitive decline.

Efficacy and safety of linagliptin to improve glucose control in older people with type 2 diabetes on stable insulin therapy: A randomized trial.

AIM: To assess the addition of linagliptin as an alternative to insulin uptitration in older people with type 2 diabetes on stable insulin therapy. MATERIALS AND METHODS: This phase 4, randomized, multicentre, double-blinded, placebo-controlled, 24-week study recruited individuals on stable insulin, with baseline HbA1c 7.0%-10.0%, aged ≥60 years and body mass index ≤45 kg/m2 . HbA1c and fasting plasma glucose were measured at study visits, and participants assessed glycaemic control with a self-monitoring blood glucose device. Adverse events (AEs) were reported during the study. RESULTS: Three hundred and two participants were randomized 1:1 to linagliptin 5 mg qd and placebo, with one third of patients from Japan. Study population age and HbA1c (baseline mean ± SD) were 72.4 ± 5.4 years and 8.2 ± 0.8%, respectively; ~80% of participants were aged ≥70 years; 80% had macrovascular complications, one third had a baseline estimated glomerular filtration rate <60 mL/min/1.73 m2 ; and half had been diagnosed with diabetes for >15 years. Linagliptin significantly improved glucose control at 24 weeks (HbA1c-adjusted mean change vs. placebo: -0.63%; P <0.0001) and the probability of achieving predefined HbA1c targets without hypoglycaemia (HbA1c <8.0%: OR 2.02; P <0.05 and HbA1c <7.0%: OR 2.44; P <0.01). Linagliptin versus placebo was well tolerated, with similar incidences of AEs, including clinically important hypoglycaemia (blood glucose <54 mg/dL) or severe hypoglycaemia. CONCLUSIONS: Addition of linagliptin improves glucose control without an excess of hypoglycaemia in older patients with type 2 diabetes on stable insulin therapy.

Association Between Metformin Initiation and Incident Dementia Among African American and White Veterans Health Administration Patients.

PURPOSE: African American patients are more likely to experience cognitive decline after type 2 diabetes mellitus onset than white patients. Metformin use has been associated with a lower risk of dementia compared with sulfonylureas. Evidence for whether this association differs by race is sparse. METHODS: Veterans Health Administration (VHA) medical record data were obtained for 73,761 African American and white patients aged ≥50 years who used the VHA from fiscal years 2000 to 2015. Patients were free of dementia and diabetes medications during fiscal years 2000 and 2001 and subsequently initiated metformin or sulfonylurea monotherapy. For race and age subgroups, Cox proportional hazards models using propensity scores and inverse probability of treatment weighting to control for confounding were computed to measure the association between metformin vs sulfonylurea initiation and incident dementia. RESULTS: After controlling for confounding, among patients aged ≥50 years, metformin vs sulfonylurea use was associated with a significantly lower risk of dementia in African American patients (hazard ratio [HR] = 0.73; 95% CI, 0.6-0.89) but not white patients (HR = 0.96; 95% CI, 0.9-1.03). The strongest magnitude of association between metformin and dementia was observed among African American patients aged 50 to 64 years (HR = 0.6; 95% CI, 0.45-0.81). Among those aged 65 to 74 years, metformin was significantly associated with lower risk of dementia in both races. Metformin was not associated with dementia in patients aged ≥75 years. CONCLUSIONS: Metformin vs sulfonylurea initiation was associated with a substantially lower risk of dementia among younger African American patients. These results may point to a novel approach for reducing the risk of dementia in African Americans with type 2 diabetes mellitus.

Branched fibers from old fast-twitch dystrophic muscles are the sites of terminal damage in muscular dystrophy.

A striking pathological feature of dystrophinopathies is the presence of morphologically abnormal branched skeletal muscle fibers. The deterioration of muscle contractile function in Duchenne muscular dystrophy is accompanied by both an increase in number and complexity of these branched fibers. We propose that when number and complexity of branched fibers reaches a critical threshold, or "tipping point," the branches in and of themselves are the site of contraction-induced rupture. In the present study, we use the dystrophic mdx mouse and littermate controls to study the prediseased dystrophic fast-twitch extensor digitorum longus (EDL) muscle at 2-3 wk, the peak myonecrotic phase at 6-9 wk, and finally, "old," at 58-112 wk. Using a combination of isolated muscle function contractile measurements coupled with single-fiber imaging and confocal microscope imaging of cleared whole muscles, we identified a distinct pathophysiology, acute fiber rupture at branch nodes, which occurs in "old" fast-twitch EDL muscle approaching the end stage of the dystrophinopathy muscle disease, where the EDL muscles are entirely composed of complexed branched fibers. This evidence supports our concept of "tipping point" where the number and extent of fiber branching reach a level where the branching itself terminally compromises muscle function, irrespective of the absence of dystrophin.