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Background The geroscience hypothesis posits that aging biological processes contribute to many age-related deficits, including the accumulation of multiple chronic diseases. Though only one facet of mitochondrial function, declines in muscle mitochondrial bioenergetic capacities may contribute to this increased susceptibility to multimorbidity. Methods The Study of Muscle, Mobility and Aging (SOMMA) assessed ex vivo muscle mitochondrial energetics in 764 older adults (mean age = 76.4, 56.5% women, and 85.9% non-Hispanic White) by high-resolution respirometry of permeabilized muscle fibers. We estimated the proportional odds ratio (POR [95% CI]) for the likelihood of greater multimorbidity (4 levels: 0 conditions, N  = 332; 1 condition, N  = 299; 2 conditions, N  = 98; or 3+ conditions, N  = 35) from an index of 11 conditions, per SD decrement in muscle mitochondrial energetic parameters. Distribution of conditions allowed for testing the associations of maximal muscle energetics with some individual conditions. Results Lower oxidative phosphorylation supported by fatty acids and/or complex I- and II-linked carbohydrates (eg, Max OXPHOSCI+CII) was associated with a greater multimorbidity index score (POR = 1.32 [1.13, 1.54]) and separately with diabetes mellitus (OR = 1.62 [1.26, 2.09]), depressive symptoms (OR = 1.45 [1.04, 2.00]) and possibly chronic kidney disease (OR = 1.57 [0.98, 2.52]) but not significantly with other conditions (eg, cardiac arrhythmia, chronic obstructive pulmonary disease). Conclusions Lower muscle mitochondrial bioenergetic capacities were associated with a worse composite multimorbidity index score. Our results suggest that decrements in muscle mitochondrial energetics may contribute to a greater global burden of disease and are more strongly related to some conditions than others. [ABSTRACT FROM AUTHOR]

Cardiorespiratory fitness and mitochondrial oxidative capacity are associated with reduced walking speed in older adults, but their impact on walking speed in older adults with diabetes has not been clearly defined. We examined differences in cardiorespiratory fitness and skeletal muscle mitochondrial oxidative capacity between older adults with and without diabetes, as well as determined their relative contribution to slower walking speed in older adults with diabetes. Participants with diabetes (n = 159) had lower cardiorespiratory fitness and mitochondrial respiration in permeabilized fiber bundles compared with those without diabetes (n = 717), following adjustments for covariates including BMI, chronic comorbid health conditions, and physical activity. Four-meter and 400-m walking speeds were slower in those with diabetes. Mitochondrial oxidative capacity alone or combined with cardiorespiratory fitness mediated ∼20–70% of the difference in walking speed between older adults with and without diabetes. Additional adjustments for BMI and comorbidities further explained the group differences in walking speed. Cardiorespiratory fitness and skeletal muscle mitochondrial oxidative capacity contribute to slower walking speeds in older adults with diabetes. Article Highlights: The contributors to slower walking speed in older adults with diabetes remain unclear. This study was conducted to answer the question of how mitochondrial oxidative capacity and cardiorespiratory fitness impact walking speed in older adults with diabetes. We found that mitochondrial oxidative capacity, cardiorespiratory fitness, and walking speed were lower in older adults with diabetes compared with those without diabetes. In addition, mitochondrial oxidative capacity and cardiorespiratory fitness contributed to slower walking speed in those with diabetes. [ABSTRACT FROM AUTHOR]

Gene expression in skeletal muscle of older individuals may reflect compensatory adaptations in response to oxidative damage that preserve tissue integrity and maintain function. Identifying associations between oxidative stress response gene expression patterns and mitochondrial function, physical performance, and muscle mass in older individuals would further our knowledge of mechanisms related to managing molecular damage that may be targeted to preserve physical resilience. To characterize expression patterns of genes responsible for the oxidative stress response, RNA was extracted and sequenced from skeletal muscle biopsies collected from 575 participants (≥70 years old) from the Study of Muscle, Mobility, and Aging. Expression levels of 21 protein‐coding RNAs related to the oxidative stress response were analyzed in relation to six phenotypic measures, including maximal mitochondrial respiration from muscle biopsies (Max OXPHOS), physical performance (VO2 peak, 400‐m walking speed, and leg strength), and muscle size (thigh muscle volume and whole‐body D3Cr muscle mass). The mRNA level of the oxidative stress response genes most consistently associated across outcomes are preferentially expressed within the mitochondria. Higher expression of mRNAs that encode generally mitochondria located proteins SOD2, TRX2, PRX3, PRX5, and GRX2 were associated with higher levels of mitochondrial respiration and VO2 peak. In addition, greater SOD2, PRX3, and GRX2 expression was associated with higher physical performance and muscle size. Identifying specific mechanisms associated with high functioning across multiple performance and physical domains may lead to targeted antioxidant interventions with greater impacts on mobility and independence. [ABSTRACT FROM AUTHOR]

Oxidative stress is considered a contributor to declining muscle function and mobility during aging; however, the underlying molecular mechanisms remain poorly described. We hypothesized that greater levels of cysteine (Cys) oxidation on muscle proteins are associated with decreased measures of mobility. Herein, we applied a novel redox proteomics approach to measure reversible protein Cys oxidation in vastus lateralis muscle biopsies collected from 56 subjects in the Study of Muscle, Mobility and Aging (SOMMA), a community‐based cohort study of individuals aged 70 years and older. We tested whether levels of Cys oxidation on key muscle proteins involved in muscle structure and contraction were associated with muscle function (leg power and strength), walking speed, and fitness (VO2 peak on cardiopulmonary exercise testing) using linear regression models adjusted for age, sex, and body weight. Higher oxidation levels of select nebulin Cys sites were associated with lower VO2 peak, while greater oxidation of myomesin‐1, myomesin‐2, and nebulin Cys sites was associated with slower walking speed. Higher oxidation of Cys sites in key proteins such as myomesin‐2, alpha‐actinin‐2, and skeletal muscle alpha‐actin were associated with lower leg power and strength. We also observed an unexpected correlation (R = 0.48) between a higher oxidation level of eight Cys sites in alpha‐actinin‐3 and stronger leg power. Despite this observation, the results generally support the hypothesis that Cys oxidation of muscle proteins impairs muscle power and strength, walking speed, and cardiopulmonary fitness with aging. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to examine associations of ectopic adipose tissue (AT) with skeletal muscle (SM) mitochondrial bioenergetics in older adults. Methods: Cross‐sectional data from 829 adults ≥70 years of age were used. Abdominal, subcutaneous, and visceral AT and thigh muscle fat infiltration (MFI) were quantified by magnetic resonance imaging. SM mitochondrial energetics were characterized in vivo (31P‐magnetic resonance spectroscopy; ATPmax) and ex vivo (high‐resolution respirometry maximal oxidative phosphorylation [OXPHOS]). ActivPal was used to measure physical activity ([PA]; step count). Linear regression adjusted for covariates was applied, with sequential adjustment for BMI and PA. Results: Independent of BMI, total abdominal AT (standardized [Std.] β = −0.21; R2 = 0.09) and visceral AT (Std. β = −0.16; R2 = 0.09) were associated with ATPmax (p < 0.01; n = 770) but not following adjustment for PA (p ≥ 0.05; n = 658). Visceral AT (Std. β = −0.16; R2 = 0.25) and thigh MFI (Std. β = −0.11; R2 = 0.24) were associated with carbohydrate‐supported maximal OXPHOS independent of BMI and PA (p < 0.05; n = 609). Total abdominal AT (Std. β = −0.19; R2 = 0.24) and visceral AT (Std. β = −0.17; R2 = 0.24) were associated with fatty acid‐supported maximal OXPHOS independent of BMI and PA (p < 0.05; n = 447). Conclusions: Skeletal MFI and abdominal visceral, but not subcutaneous, AT are inversely associated with SM mitochondrial bioenergetics in older adults independent of BMI. Associations between ectopic AT and in vivo mitochondrial bioenergetics are attenuated by PA. [ABSTRACT FROM AUTHOR]

Background Falls in the older population are a major public health concern. While many physiological and environmental factors have been associated with fall risk, muscle mitochondrial energetics has not yet been investigated. Methods In this analysis, 835 Study of Muscle, Mobility and Aging (SOMMA) participants aged 70–94 were surveyed for number of falls (total), recurrent falls (2+), and fall-related injuries over the past 12 months at baseline and again after 1 year. Skeletal muscle energetics were assessed at baseline in vivo using 31P Magnetic Resonance Spectroscopy for the maximal rate of adenosine triphosphate recovery (ATPmax) after an acute bout of exercise, and ex vivo by High-Resolution Respirometry for the maximal rate of complex I and II supported oxygen consumption (MaxOXPHOS) in permeabilized muscle fibers from the vastus lateralis. Results At least 1 fall was reported in 28.7% of SOMMA participants in the first year of the study, with 12% of older adults reporting recurrent falls (2+). Individuals who experienced recurrent falls had a slower 400-m walk gait speed (1.0 ± 0.2 vs 1.1 ± 0.2, p <.001), reported fewer alcoholic drinks per week in the past year (2.4 ± 4.3 vs 2.8 ± 4.4, p =.054), and took a significantly greater number of medication in the 30 days before their baseline visit (5.6 ± 4.4 vs 4.2 ± 3.4, p <.05). A history of falls was reported in 63% of individuals who experienced recurrent falls in the first year of the study compared to 22.8% who experienced 1 or fewer falls. MaxOXPHOS was significantly lower in those who reported recurrent falls (p =.008) compared to those with 1 or fewer falls, but there was no significant difference in ATPmax (p =.369). Neither muscle energetics measure was significantly associated with total number of falls or injurious falls, but recurrent falls were significantly higher with lower MaxOXPHOS (risk ratio = 1.33, 95% confidence interval = 1.02–1.73, p =.033). However, covariates accounted for the increased risk. Conclusions Mitochondrial energetics were largely unrelated to fall risk in older adults when accounting for variables, suggesting that the complex etiology of falls may not be related to a single "hallmark of aging" biological pathway. [ABSTRACT FROM AUTHOR]

The age-related decline in muscle mitochondrial energetics contributes to the loss of mobility in older adults. Women experience a higher prevalence of mobility impairment compared to men, but it is unknown whether sex-specific differences in muscle energetics underlie this disparity. In the Study of Muscle, Mobility and Aging (SOMMA), muscle energetics were characterized using in vivo phosphorus-31 magnetic resonance spectroscopy and high-resolution respirometry of vastus lateralis biopsies in 773 participants (56.4% women, age 70–94 years). A Short Physical Performance Battery (SPPB) score ≤8 was used to define lower-extremity mobility impairment. Muscle mitochondrial energetics were lower in women compared to men (eg, Maximal Complex I&II OXPHOS: Women = 55.06 ± 15.95; Men = 65.80 ± 19.74; p  < .001) and in individuals with mobility impairment compared to those without (eg, Maximal Complex I&II OXPHOS in women: SPPB ≥ 9 = 56.59 ± 16.22; SPPB ≤ 8 = 47.37 ± 11.85; p  < .001). Muscle energetics were negatively associated with age only in men (eg, Maximal ETS capacity: R  = −0.15, p  = .02; age/sex interaction, p  = .04), resulting in muscle energetics measures that were significantly lower in women than men in the 70–79 age group but not the 80+ age group. Similarly, the odds of mobility impairment were greater in women than men only in the 70–79 age group (70–79 age group, odds ratio [OR]age-adjusted = 1.78, 95% confidence interval [CI] = 1.03, 3.08, p  = .038; 80+ age group, ORage-adjusted = 1.05, 95% CI = 0.52, 2.15, p  = .89). Accounting for muscle energetics attenuated up to 75% of the greater odds of mobility impairment in women. Women had lower muscle mitochondrial energetics compared to men, which largely explain their greater odds of lower-extremity mobility impairment. [ABSTRACT FROM AUTHOR]

Background: Mitochondrial energetics are an important property of aging muscle, as generation of energy is pivotal to the execution of muscle contraction. However, its association with functional outcomes, including leg power and cardiorespiratory fitness is largely understudied.Methods: In the Study of Muscle, Mobility, and Aging (SOMMA), we collected vastus lateralis biopsies from older adults (n=879,70-94 years,59.2% women). Maximal state 3 respiration (Max OXPHOS) was assessed in permeabilized fiber bundles by high-resolution respirometry. Capacity for maximal adenosine triphosphate production (ATPmax) was measured in vivo by 31P magnetic resonance spectroscopy. Leg extension power was measured with a Keiser press system, and VO2 peak was determined using a standardized cardiopulmonary exercise test. Gender-stratified multivariate linear regression models were adjusted for age, race, technician/site, adiposity, and physical activity with beta-coefficients expressed per 1 SD increment in the independent variable.Results: Max OXPHOS was associated with leg power for both women (β=0.12Watts/kg,p<0.001) and men (β=0.11Watts/kg,p<0.050). ATPmax was associated with leg power for men (β=0.09Watts/kg p<0.05) but was not significant for women (β=0.03Watts/kg,p=0.11). Max OXPHOS and ATPmax were associated with VO2 peak in women and men (Max OXPHOS, βwomen=1.03mL/kg/min, βmen=1.32 mL/kg/min; ATPmax βwomen=0.87mL/kg/min, βmen=1.50mL/kg/min;all p<0.001).Conclusions: Higher muscle mitochondrial energetics measures were associated with both better cardiorespiratory fitness and greater leg power in older adults. Muscle mitochondrial energetics explained a greater degree of variance in VO2 peak compared to leg power. [ABSTRACT FROM AUTHOR]

This study examines how a state system of higher education, located in the Rocky Mountains area of the United States, allowed faculty members from the state's public institutions of higher education to control the design and implementation of a pilot assessment of statewide general education courses. One of the primary reasons faculty were allowed to control the assessment process was to assuage the commonly held fear by faculty, academic departments, and institutions that they could be punished for the poor assessment results of their students who took the pilot assessment. An important conclusion of this study is that the promise of anonymity, given by the state board of regents (and tacitly by the legislature) to individual faculty members, academic departments, and institutions, was essential to the success of the assessment process. (Contains 2 notes.)

People who become educational leadership professors usually come to their new occupation with a range of skills and experiences. Most doctoral preparation programs in educational leadership however do not always prepare future faculty members to address conflicts that arise when the actual roles and responsibilities of the new faculty member conflict with either their own norms and values or the institutions' norms, values, or mission. This case is an opportunity to consider how new faculty prepare for entrance into the professoriate. This case guides the reader through an exploration of faculty expectations of their students and themselves and how to plan student evaluations given students' characteristics in the context and the culture of the institution. Future faculty members can benefit from a thoughtful consideration of themselves and how their expectations for themselves and their students affect the teaching and learning process.

Introduction: Despite evidence for systemic mitochondrial dysfunction early in Alzheimer's disease (AD) pathogenesis, reliable approaches monitoring these key bioenergetic alterations are lacking. We used peripheral blood mononuclear cells (PBMCs) and platelets as reporters of mitochondrial function in the context of cognitive impairment and AD. Methods: Mitochondrial function was analyzed using complementary respirometric approaches in intact and permeabilized cells from older adults with normal cognition, mild cognitive impairment (MCI), and dementia due to probable AD. Clinical outcomes included measures of cognitive function and brain morphology. Results: PBMC and platelet bioenergetic parameters were lowest in dementia participants. MCI platelets exhibited higher maximal respiration than normocognitives. PBMC and platelet respiration positively associated with cognitive ability and hippocampal volume, and negatively associated with white matter hyperintensities. Discussion: Our findings indicate blood‐based bioenergetic profiling can be used as a minimally invasive approach for measuring systemic bioenergetic differences associated with dementia, and may be used to monitor bioenergetic changes associated with AD risk and progression. Highlights: Peripheral cell bioenergetic alterations accompanied cognitive decline in older adults with mild cognitive impairment (MCI) and Alzheimer's disease (AD) and related dementia (DEM).Peripheral blood mononuclear cells (PBMC) and platelet glucose‐mediated respiration decreased in participants with dementia compared to normocognitive controls (NC).PBMC fatty‐acid oxidation (FAO)‐mediated respiration progressively declined in MCI and AD compared to NC participants, while platelet FAO‐mediated respiration exhibited an inverse‐Warburg effect in MCI compared to NC participants.Positive associations were observed between bioenergetics and Modified Preclinical Alzheimer's Cognitive Composite, and bioenergetics and hippocampal volume %, while a negative association was observed between bioenergetics and white matter hyperintensities.Systemic mitochondrial dysfunction is associated with cognitive decline. [ABSTRACT FROM AUTHOR]

Many college faculty react to student outcomes assessment the way most people react when they see a rattlesnake within striking distance. Common faculty reactions to the perceived threat of assessment include metaphorically running away and throwing rocks or sticks at it. Like a hiker in the desert doing her best to avoid being struck when she encounters a rattlesnake, a number of faculty members react to assessment activities by doing what they can to avoid or resist them. In this article, the author suggests that one way to address faculty avoidance or resistance is to create an antidote. In a way similar to how anti-venom is created for venomous bites or stings--that is, by receiving small doses of assessment over time--faculty may be able to build up their assessment immunity. Put another way, when assessment work is introduced to faculty in a way that is both collegial and collaborative, and when it is given in small, manageable doses while emphasizing the positive aspects of assessment, faculty resistance may be reduced significantly.

In 1998, the Utah State Board of Regents ordered a sample administration of American College Testing's Collegiate Assessment of Academic Proficiency (CAAP), a test of general knowledge, for Utah System of Higher Education (USHE) students. The pilot test was administered to 3,148 Utah college students who were completing their sophomore year at one of Utah's nine public colleges or universities. Although Utah college and university students scored above the national average, the results of the CAAP were considered a disappointment. Faculty throughout the state believed that the CAAP was an inadequate test of general education because: (1) the test was not aligned with course content or objectives; (2) the CAAP did not correlate with students' grade point averages; (3) the findings were too general and failed to offer any guidance to faculty; and 4) the CAAP was not administered to students who had taken any specific courses in common or completed similar degree requirements. Consequently, the Regents' Task Force for General Education, an ad hoc faculty committee charged by the regents with examining general education in the state, asked the regents to allow faculty members to create their own assessment instruments to measure the general education knowledge of Utah college and university students. After agreeing on general education competences, statewide faculty began to develop the pilot assessment. It was then administered to 2,141 students at the nine USHE institutions at the beginning and the end of the spring 2001 semester. There were dramatic improvements in student learning between the beginning and the end of the semester. A subsequent study was conducted to examine the purposes of the pilot assessment, how the pilot assessment was organized and implemented, what methodological issues were involved in creating the pilot assessment, and what recommendations participants in the study had for future assessment endeavors. This article highlights the major findings of the study and presents several recommendations for practioners and researchers. (Contains 1 note.)

Abstract This study examined the attitudes of undergraduate teacher education majors and education faculty about the value of connecting educational research and practice in the university and in K12 schools. [...]