Contractile regulation of the glucocorticoid-sensitive transcriptome in young and aged skeletal muscle.

Elevated glucocorticoids alter the skeletal muscle transcriptome to induce a myopathy characterized by muscle atrophy, muscle weakness, and decreased metabolic function. These effects are more likely to occur and be more severe in aged muscle. Resistance exercise can blunt development of glucocorticoid myopathy in young muscle, but the potential to oppose the signals initiating myopathy in aged muscle is unknown. To answer this, young (4-month-old) and aged (24-25-month-old) male C57BL/6 mice were randomized to receive either an intraperitoneal (IP) injection of dexamethasone (DEX; 2 mg/kg) or saline as a control. Two hours post-injections, tibialis anterior (TA) muscles of mice were subjected to unilateral high force contractions. Muscles were harvested four hours later. The glucocorticoid- and contraction-sensitive genes were determined by RNA sequencing. The number of glucocorticoid-sensitive genes was similar between young and aged muscle. Contractions opposed changes to more glucocorticoid-sensitive genes in aged muscle, with this outcome primarily occurring when hormone levels were elevated. Glucocorticoid-sensitive gene programs opposed by contractions were primarily related to metabolism in young mice and muscle size regulation and inflammation in aged mice. In silico analysis implied Peroxisome proliferator-activated receptor gamma-1 (PPARG) contributed to the contraction-induced opposition of glucocorticoid-sensitive genes in aged muscle. Increasing PPARG expression in the TA of aged mice using Adeno-associated virus serotype 9 partially counteracted the glucocorticoid-induced reduction in Runt-related transcription factor 1 (Runx1) mRNA content, recapitulating the effects observed by contractions. Overall, these data contribute to our understanding of the contractile regulation of the glucocorticoid transcriptome in aged skeletal muscle.

Function, cognition, and quality of life among older adults with lung cancer who live alone: A prospective cohort study.

INTRODUCTION: Among older adults without cancer, living alone is associated with poor health outcomes. However, among older adults with non-small cell lung cancer (NSCLC) who live alone, data on function, cognition, and quality of life (QOL) during systemic treatment remain limited. MATERIALS AND METHODS: We enrolled adults aged ≥65 with advanced NSCLC starting a new chemotherapy, immunotherapy, and/or targeted therapy regimen with non-curative intent. Patients completed geriatric assessments including instrumental activities of daily living (IADL), Montreal Cognitive Assessment, and QOL pretreatment and at 1, 2, 4, and 6 months, or until treatment discontinuation, whichever occurred earlier. We categorized change in IADL, cognition, and QOL as stable/improved, declined with recovery, or declined without recovery using clinically meaningful definitions of change. We used multinomial logistic regression to compare change between patients who lived alone versus with others. RESULTS: Among 149 patients, median age was 73; 21% lived alone. Pretreatment IADL, cognition, and QOL scores were similar between older adults who lived alone versus with others. During NSCLC treatment, older adults who lived alone had similar trajectories of function (52% functional decline vs 38%), cognition (43% cognitive decline vs 50%), and QOL (45% QOL decline vs 44%) compared with those who lived with others. In unadjusted analyses, patients who lived alone were more likely to develop functional decline with recovery (reference category: stable/improved function) than those who lived with others (relative risk ratio 4.07, 95% CI 1.14-14.6, p = 0.03). However, this association was not observed after adjusting for age, race, prior NSCLC treatment, current treatment group, and pretreatment geriatric assessment differences. There were no differences in cognitive or QOL trajectories in unadjusted or adjusted analyses. DISCUSSION: Approximately half of older adults with advanced NSCLC who lived alone were able to maintain their function, cognition, and QOL during NSCLC treatment, which was similar to older adults who lived with others. Many older adults with advanced NSCLC who live alone can receive systemic treatment with individualized supportive care.

Comparison of objectively measured and estimated cardiorespiratory fitness to predict all-cause and cardiovascular disease mortality in adults: A systematic review and meta-analysis of 42 studies representing 35 cohorts and 3.8 million observations.

BACKGROUND: Cardiorespiratory fitness (CRF) is a powerful health marker recommended by the American Heart Association as a clinical vital sign. Comparing the predictive validity of objectively measured CRF (the "gold standard") and estimated CRF is clinically relevant because estimated CRF is more feasible. Our objective was to meta-analyze cohort studies to compare the associations of objectively measured, exercise-estimated, and non-exercise-estimated CRF with all-cause and cardiovascular disease (CVD) mortality in adults. METHODS: Systematic searches were conducted in 9 databases (MEDLINE, SPORTDiscus, Embase, Scopus, PsycINFO, Web of Science, PubMed, CINAHL, and the Cochrane Library) up to April 11, 2024. We included full-text refereed cohort studies published in English that quantified the association (using risk estimates with 95% confidence intervals (95%CIs)) of objectively measured, exercise-estimated, and non-exercise-estimated CRF with all-cause and CVD mortality in adults. CRF was expressed as metabolic equivalents (METs) of task. Pooled relative risks (RR) for all-cause and CVD mortality per 1-MET (3.5 mL/kg/min) higher level of CRF were quantified using random-effects models. RESULTS: Forty-two studies representing 35 cohorts and 3,813,484 observations (81% male) (362,771 all-cause and 56,471 CVD deaths) were included. The pooled RRs for all-cause and CVD mortality per higher MET were 0.86 (95%CI: 0.83-0.88) and 0.84 (95%CI: 0.80-0.87), respectively. For both all-cause and CVD mortality, there were no statistically significant differences in RR per higher MET between objectively measured (RR range: 0.86-0.90) and maximal exercise-estimated (RR range: 0.85-0.86), submaximal exercise-estimated (RR range: 0.91-0.94), and non-exercise-estimated CRF (RR range: 0.81-0.85). CONCLUSION: Objectively measured and estimated CRF showed similar dose-response associations for all-cause and CVD mortality in adults. Estimated CRF could provide a practical and robust alternative to objectively measured CRF for assessing mortality risk across diverse populations. Our findings underscore the health-related benefits of higher CRF and advocate for its integration into clinical practice to enhance risk stratification.

First come, first observed: Utilizing observation as a pedagogical tool to transform leadership learning.

Leadership observation is a technique that relies on active and inactive recall to enhance learning through connecting theoretic concepts to real-world examples. This article makes the case that leadership observation should be thoughtfully used as a pedagogical tool to aid in students' leadership learning. Knowledge will be shared through personal narratives and practical strategies. Leadership educators should consider implementing moments of intentional observation into their curriculum to deepen student connections and prepare them for future endeavors.

Evaluating concordance between International Myeloma Working Group (IMWG) frailty score and simplified frailty scale among older adults with multiple myeloma.

INTRODUCTION: Several frailty assessment tools exist for classifying older adults with multiple myeloma (MM) by their frailty status, such as the International Myeloma Working Group (IMWG) frailty score and the simplified frailty scale. The level of agreement between the IMWG frailty score and the simplified frailty scale remains unknown. MATERIALS AND METHODS: In a cross-sectional analysis of a prospective cohort study, we identified adults ≥50y initiating a new treatment regimen for MM who underwent a baseline geriatric assessment (GA). Using data from the GA and electronic health records, we measured IMWG frailty score and the simplified frailty scale, and classified patients by frailty status. We merged the fit and intermediate-fit categories of IMWG frailty score to create a binary category (frail, non-frail) for comparison with simplified frailty scale and measured their agreement using Cohen's Kappa statistic. We tested the diagnostic utility of simplified frailty scale as a screening tool using IMWG frailty score as the gold standard, using sensitivity, specificity, and decision curve analysis (DCA). RESULTS: Three hundred older adults were included with a median age at diagnosis of 64y; 56 % were male and 63 % were non-Hispanic White. By IMWG frailty score, 41 % were fit, 38 % intermediate-fit, and 21 % frail, while simplified frailty scale indicated 22 % frail and 78 % non-frail patients. The agreement between IMWG frailty score and simplified frailty scale was moderate (κ = 0.43); 19 % of the patients were misclassified. Despite discordance, when testing simplified frailty scale as a screening tool, we found a sensitivity of 56 % and specificity of 87 % to diagnose frailty. Substituting patient-reported performance status (PS) instead of physician reported ECOG PS led to a sensitivity of 91 % and specificity of 61 %. DCA showed that using simplified frailty scale (with patient reported PS) as a screening tool led to a 43-44 % reduction in the number of unnecessary GAs across reasonable threshold probabilities. DISCUSSION: IMWG frailty score and simplified frailty scale have limited agreement with each other. This creates a possibility of misclassification bias and poses difficulty in comparing existing literature on frail patients with MM. Despite discordance, simplified frailty scale may have a potential role as a screening tool, when using patient-reported PS.

Weakness Status is Differentially Associated with Time to Diabetes in Americans.

Background: The purpose of this study was to evaluate the associations of (1) individual absolute and body size normalized weakness cut-points, and (2) the collective weakness classifications on time to diabetes in Americans. Methods: We analyzed data from 9577 adults aged at least 50-years from the Health and Retirement Study. Diabetes diagnosis was self-reported. A handgrip dynamometer measured handgrip strength (HGS). Males with HGS <35.5 kg (absolute), <0.45 kg/kg (normalized to body weight), or <1.05 kg/kg/m2 (normalized to BMI) were categorized as weak. Females were classified as weak if their HGS was <20.0 kg, <0.337 kg/kg, or <0.79 kg/kg/m2. Compounding weakness included falling below 1, 2, or all 3 cut-points. Results: Persons below the body weight normalized weakness cut-points had a 1.29 (95% confidence interval (CI): 1.15-1.47) higher hazard for incident diabetes, while those below the BMI normalized cut-points had a 1.30 (CI: 1.13-1.51) higher hazard. The association between absolute weakness and incident diabetes was insignificant (hazard ratio: 1.06; CI: 0.91-1.24). Americans below 1, 2, or all 3 collective weakness categories had a 1.28 (CI: 1.10-1.50), 1.29 (CI: 1.08-1.52), and 1.33 (CI: 1.09-1.63) higher hazard for the incidence of diabetes, respectively. Conclusions: Our findings indicate that while absolute weakness, which is confounded by body size, was not associated with time to diabetes, adjusting for the influence of body size by normalizing HGS to body weight and BMI was significantly associated with time to diabetes. This suggests that muscle strength, not body size, may be driving such associations with time to diabetes.

Single-cell spatial transcriptomics reveals distinct patterns of dysregulation in non-neuronal and neuronal cells induced by the Trem2R47H Alzheimer's risk gene mutation.

The R47H missense mutation of the TREM2 gene is a known risk factor for development of Alzheimer's Disease. In this study, we analyze the impact of the Trem2R47H mutation on specific cell types in multiple cortical and subcortical brain regions in the context of wild-type and 5xFAD mouse background. We profile 19 mouse brain sections consisting of wild-type, Trem2R47H, 5xFAD and Trem2R47H; 5xFAD genotypes using MERFISH spatial transcriptomics, a technique that enables subcellular profiling of spatial gene expression. Spatial transcriptomics and neuropathology data are analyzed using our custom pipeline to identify plaque and Trem2R47H-induced transcriptomic dysregulation. We initially analyze cell type-specific transcriptomic alterations induced by plaque proximity. Next, we analyze spatial distributions of disease associated microglia and astrocytes, and how they vary between 5xFAD and Trem2R47H; 5xFAD mouse models. Finally, we analyze the impact of the Trem2R47H mutation on neuronal transcriptomes. The Trem2R47H mutation induces consistent upregulation of Bdnf and Ntrk2 across many cortical excitatory neuron types, independent of amyloid pathology. Spatial investigation of genotype enriched subclusters identified spatially localized neuronal subpopulations reduced in 5xFAD and Trem2R47H; 5xFAD mice. Overall, our MERFISH spatial transcriptomics analysis identifies glial and neuronal transcriptomic alterations induced independently by 5xFAD and Trem2R47H mutations, impacting inflammatory responses in microglia and astrocytes, and activity and BDNF signaling in neurons.

Discovery of an embryonically derived bipotent population of endothelial-macrophage progenitor cells in postnatal aorta.

Converging evidence indicates that extra-embryonic yolk sac is the source of both macrophages and endothelial cells in adult mouse tissues. Prevailing views are that these embryonically derived cells are maintained after birth by proliferative self-renewal in their differentiated states. Here we identify clonogenic endothelial-macrophage (EndoMac) progenitor cells in the adventitia of embryonic and postnatal mouse aorta, that are independent of Flt3-mediated bone marrow hematopoiesis and derive from an early embryonic CX3CR1+ and CSF1R+ source. These bipotent progenitors are proliferative and vasculogenic, contributing to adventitial neovascularization and formation of perfused blood vessels after transfer into ischemic tissue. We establish a regulatory role for angiotensin II, which enhances their clonogenic and differentiation properties and rapidly stimulates their proliferative expansion in vivo. Our findings demonstrate that embryonically derived EndoMac progenitors participate in local vasculogenic responses in the aortic wall by contributing to the expansion of endothelial cells and macrophages postnatally.

Geriatric assessment for the practicing clinician: The why, what, and how.

Older adults with cancer heterogeneously experience health care, treatment, and symptoms. Geriatric assessment (GA) offers a comprehensive evaluation of an older individual's health status and can predict cancer-related outcomes in individuals with solid tumors and those with hematologic malignancies. In the last decade, randomized controlled trials have demonstrated the benefits of GA and GA management (GAM), which uses GA information to provide tailored intervention strategies to address GA impairments (e.g., implementing physical therapy for impaired physical function). Multiple phase 3 clinical trials in older adults with solid tumors and hematologic malignancies have demonstrated that GAM improves treatment completion, quality of life, communication, and advance care planning while reducing treatment-related toxicity, falls, and polypharmacy. Nonetheless, implementation and uptake of GAM remain challenging. Various strategies have been proposed, including the use of GA screening tools, to identify patients most likely to benefit from GAM, the systematic engagement of the oncology workforce in the delivery of GAM, and the integration of technologies like telemedicine and mobile health to enhance the availability of GA and GAM interventions. Health inequities in minoritized groups persist, and systematic GA implementation has the potential to capture social determinants of health that are relevant to equitable care. Caregivers play an important role in cancer care and experience burden themselves. GA can guide dyadic supportive care interventions, ultimately helping both patients and caregivers achieve optimal health.

Activity levels across the intensity spectrum in athletes: a systematic review protocol.

Physical activity (PA) promotes better cardiometabolic health, physical function, brain health and longevity. In contrast, prolonged sedentary behaviour (SB) is a risk factor for many chronic diseases and poor health. Limited research has evaluated or synthesised how competitive sports participation influences PA across the lifespan. Some evidence suggests, ironically, that former competitive athletes may be insufficiently active and current athletes may be highly sedentary away from sport. This study describes the protocol for a systematic review and meta-analysis on activity levels across the intensity spectrum in athletes, addressing the primary research question: is sports participation significantly associated with PA and/or SB among current and former competitive athletes? PubMed, Embase, Cochrane Database of Systematic Reviews, Web of Science and SPORTDiscus databases will be searched. Two reviewers will independently screen titles/abstracts and full texts of selected abstracts. Data will be extracted regarding the study population, sport played, PA measures and protocols, outcomes of interest and findings. Primary outcomes will include step counts, daily activity across the intensity spectrum (ie, sedentary, light, moderate and vigorous PA), metabolic equivalent of task and whole-day energy expenditure. Secondary outcomes will include additional accelerometry measures of PA, activity patterns and self-reported PA. The risk of bias will be assessed using the National Institutes of Health Study Quality Assessment Tools. Extracted data will be presented using narrative synthesis and tabular presentation. Meta-analyses will be conducted to determine outcomes with sufficient data.PROSPERO registration number: CRD42024469267.https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=469267.

Can Periprosthetic Joint Infection of Tumor Prostheses Be Controlled With Debridement, Antibiotics, and Implant Retention?

BACKGROUND: Two-stage revision for periprosthetic joint infection (PJI) in patients who have undergone segmental replacement of the distal femur or proximal tibia after tumor resection can be associated with considerable morbidity, pain, and risk of complications because the procedure often results in removal of long, well-fixed stems from the diaphysis. A less-aggressive surgical approach, such as debridement, antibiotics, and implant retention (DAIR), may be attractive to patients and surgeons because of less morbidity, but the likelihood of eradicating infection in comparison to the traditional two-stage revision is not well established for oncology patients. Furthermore, the relative risk of subsequent amputation for DAIR versus two-stage revision has not been defined for this population. QUESTIONS/PURPOSES: (1) How does DAIR compare with two-stage revision in terms of infection control for patients with distal femoral or proximal tibial segmental modular endoprostheses? (2) Is DAIR as an initial procedure associated with an increased risk of amputation compared with two-stage revision for infection? METHODS: From the longitudinally maintained orthopaedic oncology surgical database at our institution, we identified 69 patients who had been treated for a clinical diagnosis of PJI at the knee between 1993 and 2015. We excluded 32% (22) of patients who did not meet at least one of the major criteria of the Musculoskeletal Infection Society (MSIS) for PJI, 3% (2) of patients who underwent immediate amputation, 3% (2) of patients who had a follow-up time of < 24 months, and 7% (5) of patients who did not have a primary tumor of the distal femur or proximal tibia. The study consisted of 38 patients, of whom eight underwent two-stage revision, 26 underwent DAIR, and four underwent extended DAIR (removal of all segmental components but with retention of stems and components fixed in bone) for their initial surgical procedure. To be considered free of infection, patients had to meet MSIS standards, including no positive cultures, drainage, or surgical debridement for a minimum of 2 years from the last operation. Factors associated with time-dependent risk of infection relapse, clearance, amputation, and patient survival were analyzed using Kaplan-Meier survivorship curves and the log-rank test to compare factors. Association of demographic and treatment factors was assessed using chi-square and Fisher exact tests. RESULTS: Continuous infection-free survival at 5 years was 16% (95% CI 2% to 29%) for patients undergoing DAIR compared with 75% (95% CI 45% to 100%) for patients undergoing two-stage revision (p = 0.006). The median (range) number of total surgical procedures was 3 per patient (1 to 10) for DAIR and 2 (2 to 5) for two-stage revision. Twenty-nine percent (11 of 38) of patients eventually underwent amputation. Survival without amputation was 69% (95% CI 51% to 86%) for DAIR compared with 88% (95% CI 65% to 100%) for two-stage revision at 5 years (p = 0.34). The cumulative proportion of patients achieving infection-free status (> 2 years continuously after last treatment) and limb preservation was 58% (95% CI 36% to 80%) for patients initially treated with DAIR versus 87% (95% CI 65% to 100%) for patients first treated with two-stage revision (p = 0.001). CONCLUSION: Infection control was better with two-stage revision than DAIR. The chance of eventual clearance of infection with limb preservation was better when two-stage revision was chosen as the initial treatment. However, the loss to follow-up in the two-stage revision group would likely make the true proportion of infection control lower than our estimate. Our experience would suggest that the process of infection eradication is a complex and difficult one. Most patients undergo multiple operations. Nearly one-third of patients eventually underwent amputation, and this was a serious risk for both groups. While we cannot strongly recommend one approach over the other based on our data, we would still consider the use of DAIR in patients who present with acute short duration of symptoms (< 3 weeks), no radiographic signs of erosion around fixed implants, and organisms other than Staphylococcus aureus. We would advocate the extended DAIR procedure with removal of all segmental or modular components, and we would caution patients that there is a high likelihood of needing further surgery. A prospective trial with strict adherence to indications may be needed to evaluate the relative merits of an extended DAIR procedure versus a two-stage revision. LEVEL OF EVIDENCE: Level III, therapeutic study.

Factors affecting advance care planning in older adults with cancer.

INTRODUCTION: Advance care planning (ACP) has been widely endorsed and recommended for its many potential benefits, including improved end-of-life (EOL) care, enhanced satisfaction with care, and reduced anxiety and depression. However, little is known about the ACP completion rates and factors affecting ACP among older adults with cancer. This study's purpose was to examine biological, psychological, and social factors affecting ACP in this population. MATERIALS AND METHODS: Data from the 2002 to 2016 waves of exit interviews from the national longitudinal Health and Retirement Study were analyzed. The sample included 1088 decedents, aged 55 and over, who had a diagnosis of cancer. The exit interviews were completed by a proxy respondent (usually the next of kin of the decedents). ACP outcomes included: having EOL care discussion, durable power of attorney (DPOA), and advance directives (ADs). Multiple logistic regression models were conducted to examine the relationships between predictor variables and each of the three ACP outcome variables. RESULTS: Approximately 65% of the sample had ever discussed EOL care, 61.9% had an assigned DPOA, and 54.1% had ADs. Regression results showed that higher age, Black race, high school and above education, being widowed/never married, higher multimorbidity, and more limitations in activities of daily living and instrumental activities of daily living were significantly associated with the three ACP variables. Surprisingly, Black race was associated with higher odds of ever discussing EOL care and having ADs; high school and above education was associated with lower odds of all three ACP components. DISCUSSION: The majority of participants in this study had discussed EOL care, had an assigned DPOA, and had ADs. However, most participants were White/Caucasian and had completed high school education. Future research that includes more diverse and minoritized participants is needed. Also, the contrasting association of Black race and higher educational status with ACP outcomes warrant further exploration in future studies.

APOE Christchurch enhances a disease-associated microglial response to plaque but suppresses response to tau pathology.

Background: Apolipoprotein E ε4 (APOE4) is the strongest genetic risk factor for late-onset Alzheimer's disease (LOAD). A recent case report identified a rare variant in APOE, APOE3-R136S (Christchurch), proposed to confer resistance to autosomal dominant Alzheimer's Disease (AD). However, it remains unclear whether and how this variant exerts its protective effects. Methods: We introduced the R136S variant into mouse Apoe (ApoeCh) and investigated its effect on the development of AD-related pathology using the 5xFAD model of amyloidosis and the PS19 model of tauopathy. We used immunohistochemical and biochemical analysis along with single-cell spatial transcriptomics and proteomics to explore the impact of the ApoeCh variant on AD pathological development and the brain's response to plaques and tau. Results: In 5xFAD mice, ApoeCh enhances a Disease-Associated Microglia (DAM) phenotype in microglia surrounding plaques, and reduces plaque load, dystrophic neurites, and plasma neurofilament light chain. By contrast, in PS19 mice, ApoeCh suppresses the microglial and astrocytic responses to tau-laden neurons and does not reduce tau accumulation or phosphorylation, but partially rescues tau-induced synaptic and myelin loss. We compared how microglia responses differ between the two mouse models to elucidate the distinct DAM signatures induced by ApoeCh. We identified upregulation of antigen presentation-related genes in the DAM response in a PS19 compared to a 5xFAD background, suggesting a differential response to amyloid versus tau pathology that is modulated by the presence of ApoeCh. Conclusions: These findings highlight the ability of the ApoeCh variant to modulate microglial responses based on the type of pathology, enhancing DAM reactivity in amyloid models and dampening neuroinflammation to promote protection in tau models. This suggests that the Christchurch variant's protective effects likely involve multiple mechanisms, including changes in receptor binding and microglial programming.

Intrinsic capacity and survival among older adults with gastrointestinal malignancies: The Cancer and Aging Resilience Evaluation registry.

BACKGROUND: Intrinsic capacity (IC) was introduced by the World Health Organization (WHO) as a marker of healthy aging, and is defined as the combination of an individual's physical, mental, and psychological capacities. This study aimed to assess IC via a patient-reported geriatric assessment (GA) and evaluate its association with survival among older adults with gastrointestinal (GI) malignancies. METHODS: Data were used from a single-institution prospective registry of older adults undergoing GA before cancer therapy. Key domains of IC (vitality, locomotion, and sensory [hearing and visual], psychological, and cognitive capacities) were captured via GA, and each was given a score of 0 or 1 (0, impaired) to compute the total IC score (range, 0-6, where 6 indicates no impairment and ≤5 indicates impairment in ≥1 domains). A frailty index (FI) was measured via the deficit accumulation method. Cox regression models and Kaplan-Meier curves were used to examine the impact of IC impairment on survival. RESULTS: The study included 665 patients; the median age was 68 years, 57.4% were men, and 72.9% were White. The median IC score was 4, and 79.3% of participants showed impairment in ≥1 domains of IC. Most commonly impaired domains were locomotion (48.7%) and vitality (43.9%). IC was inversely associated with FI (Spearman coefficient, -0.75; p < .001). IC impairment was associated with inferior overall survival (score, 4-5: adjusted hazard ratio [aHR], 1.7; 95% CI, 1.11-2.48; score, 2-3: aHR, 1.9; 95% CI, 1.30-2.85; score, 0-1: aHR, 1.9; 95% CI, 1.11-2.48). CONCLUSIONS: IC impairment is associated with frailty and reduced overall survival in older patients with GI malignancies. GA can be used to screen for IC impairment as recommended by the WHO. PLAIN LANGUAGE SUMMARY: The World Health Organization introduced intrinsic capacity as a marker of healthy aging. Intrinsic capacity is the combination of an individual's physical, mental, and psychological capacities. It contains six key domains: vitality, locomotion, and sensory (hearing and visual), psychological, and cognitive capacities. Older adults with cancer are susceptible to a decrease in intrinsic capacity as a result of cancer and the aging process. In this study, we aimed to assess the intrinsic capacity for patients with gastrointestinal cancer and also identify whether there exists any association of intrinsic capacity with overall survival. We identified that approximately 80% of this population had one or more impaired domains, and more intrinsic capacity impairment was associated with reduced overall survival.

Short-term aerobic exercise prevents development of glucocorticoid myopathic features in aged skeletal muscle in a sex-dependent manner.

Older adults are vulnerable to glucocorticoid-induced muscle atrophy and weakness, with sex potentially influencing their susceptibility to those effects. Aerobic exercise can reduce glucocorticoid-induced muscle atrophy in young rodents. However, it is unknown whether aerobic exercise can prevent glucocorticoid myopathy in aged muscle. The objectives of this study were to define the extent to which sex influences the development of glucocorticoid myopathy in aged muscle, and to determine the extent to which aerobic exercise training protects against myopathy development. Twenty-four-month-old female (n = 30) and male (n = 33) mice were randomized to either sedentary or aerobic exercise groups. Within their respective groups, mice were randomized to either daily treatment with dexamethasone (DEX) or saline. Upon completing treatments, the contractile properties of the triceps surae complex were assessed in situ. DEX marginally lowered muscle mass and soluble protein content in both sexes, which was attenuated by aerobic exercise only in females. DEX increased sub-tetanic force and rate of force development only in females, which was not influenced by aerobic exercise. Muscle fatigue was higher in both sexes following DEX, but aerobic exercise prevented fatigue induction only in females. The sex-specific differences to muscle function in response to DEX treatment coincided with sex-specific changes to the content of proteins related to calcium handling, mitochondrial quality control, reactive oxygen species production, and glucocorticoid receptor in muscle. These findings define several important sexually dimorphic changes to aged skeletal muscle physiology in response to glucocorticoid treatment and define the capacity of short-term aerobic exercise to protect against those changes. KEY POINTS: There are sexually dimorphic effects of glucocorticoids on aged skeletal muscle physiology. Glucocorticoid-induced changes to aged muscle contractile properties coincide with sex-specific differences in the content of calcium handling proteins. Aerobic exercise prevents glucocorticoid-induced fatigue only in aged females and coincides with differences in the content of mitochondrial quality control proteins and glucocorticoid receptors.

Complimentary vertebrate Wac models exhibit phenotypes relevant to DeSanto-Shinawi Syndrome.

Monogenic syndromes are associated with neurodevelopmental changes that result in cognitive impairments, neurobehavioral phenotypes including autism and attention deficit hyperactivity disorder (ADHD), and seizures. Limited studies and resources are available to make meaningful headway into the underlying molecular mechanisms that result in these symptoms. One such example is DeSanto-Shinawi Syndrome (DESSH), a rare disorder caused by pathogenic variants in the WAC gene. Individuals with DESSH syndrome exhibit a recognizable craniofacial gestalt, developmental delay/intellectual disability, neurobehavioral symptoms that include autism, ADHD, behavioral difficulties and seizures. However, no thorough studies from a vertebrate model exist to understand how these changes occur. To overcome this, we developed both murine and zebrafish Wac/wac deletion mutants and studied whether their phenotypes recapitulate those described in individuals with DESSH syndrome. We show that the two Wac models exhibit craniofacial and behavioral changes, reminiscent of abnormalities found in DESSH syndrome. In addition, each model revealed impacts to GABAergic neurons and further studies showed that the mouse mutants are susceptible to seizures, changes in brain volumes that are different between sexes and relevant behaviors. Finally, we uncovered transcriptional impacts of Wac loss of function that will pave the way for future molecular studies into DESSH. These studies begin to uncover some biological underpinnings of DESSH syndrome and elucidate the biology of Wac, with advantages in each model.

Groundwater solutes influence the adsorption of short-chain perfluoroalkyl acids (PFAA) to colloidal activated carbon and impact performance for in situ groundwater remediation.

Subsurface injection of colloidal activated carbon (CAC) is an in situ remediation strategy for perfluoroalkyl acids (PFAA), but the influence of groundwater solutes on longevity is uncertain, particularly for short-chain PFAA. We quantify the impact of inorganic anions, dissolved organic matter (DOM), and stabilizing polymer on PFAA adsorption to a commercial CAC. Surface characterization supported PFAA chain-length dependent adsorption results and mechanisms are provided. Inorganic anions decreased adsorption for short-chain PFAA (<7 perfluorinated carbons) due to competitive effects, while long-chain PFAA (≥ 7 perfluorinated carbons) were less impacted. DOM decreased adsorption of all PFAA in a chain-length dependent manner. High DOM concentrations (10 mg/L, ∼5 mg OC/L) decreased PFOA adsorption by a factor of 2, PFPeA by one order of magnitude, and completely hindered PFBA adsorption. High MW DOM has less impact on short-chain PFAA than low MW DOM, possibly due to differences in the ability to access CAC micropores. Low DOM concentrations (1 mg/L, ∼0.5 mg OC/L) did not impact adsorption. CMC (90 kDa average MW) had negligible impact on PFAA adsorption likely due to minimal CAC surface coverage. Longevity modeling demonstrated that groundwater solutes limit the capacity for PFAA in a CAC barrier, particularly for short-chain PFAA.

Reduced Insulin Resistance and Oxidative Stress in a Mouse Model of Metabolic Syndrome following Twelve Weeks of Citrus Bioflavonoid Hesperidin Supplementation: A Dose-Response Study.

Metabolic syndrome (MetS) is a cluster of metabolic abnormalities affecting ~25% of adults and is linked to chronic diseases such as cardiovascular disease, cancer, and neurodegenerative diseases. Oxidative stress and inflammation are key drivers of MetS. Hesperidin, a citrus bioflavonoid, has demonstrated antioxidant and anti-inflammatory properties; however, its effects on MetS are not fully established. We aimed to determine the optimal dose of hesperidin required to improve oxidative stress, systemic inflammation, and glycemic control in a novel mouse model of MetS. Male 5-week-old C57BL/6 mice were fed a high-fat, high-salt, high-sugar diet (HFSS; 42% kcal fat content in food and drinking water with 0.9% saline and 10% high fructose corn syrup) for 16 weeks. After 6 weeks of HFSS, mice were randomly allocated to either the placebo group or low- (70 mg/kg/day), mid- (140 mg/kg/day), or high-dose (280 mg/kg/day) hesperidin supplementation for 12 weeks. The HFSS diet induced significant metabolic disturbances. HFSS + placebo mice gained almost twice the weight of control mice (p < 0.0001). Fasting blood glucose (FBG) increased by 40% (p < 0.0001), plasma insulin by 100% (p < 0.05), and HOMA-IR by 150% (p < 0.0004), indicating insulin resistance. Hesperidin supplementation reduced plasma insulin by 40% at 140 mg/kg/day (p < 0.0001) and 50% at 280 mg/kg/day (p < 0.005). HOMA-IR decreased by 45% at both doses (p < 0.0001). Plasma hesperidin levels significantly increased in all hesperidin groups (p < 0.0001). Oxidative stress, measured by 8-OHdG, was increased by 40% in HFSS diet mice (p < 0.001) and reduced by 20% with all hesperidin doses (p < 0.005). In conclusion, hesperidin supplementation reduced insulin resistance and oxidative stress in HFSS-fed mice, demonstrating its dose-dependent therapeutic potential in MetS.