Caloric Restriction Intervention Alters Specific Circulating Biomarkers of the Senescence-Associated Secretome in Middle-Aged and Older Adults With Obesity and Prediabetes in an 18-Week Randomized Controlled Trial.

Cellular senescence is a biological aging process that is exacerbated by obesity and leads to inflammation and age- and obesogenic-driven chronic diseases including type 2 diabetes. Caloric restriction (CR) may improve metabolic function in part by reducing cellular senescence and the pro-inflammatory senescence-associated phenotype (SASP). We conducted an ancillary investigation of an 18-week randomized controlled trial (RCT) of CR (n = 31) or Control (n = 27) in 58 middle-aged/older adults (57.6 ±â€…5.8 years; 75% Women) with obesity and prediabetes. We measured mRNA expression of select senescence and apoptosis genes in blood CD3 + T cells (qRT-PCR) and a panel of 25 plasma SASP proteins (Luminex/multiplex; ELISA). Participants randomized to CR lost -10.8 ±â€…0.9 kg (-11.3% ±â€…5.4%) over 18 weeks compared with +0.5 ±â€…0.9 kg (+0.03% ±â€…3.5%) in Control group. T-cell expression of senescence biomarkers, p16INK4a and p21CIP1/WAF1, and apoptosis markers, BCL2L1 and BAK1, was not different between CR and Control groups in age, race, and sex-adjusted mixed models (p > .05, all). Iterative principal axis factor analysis was used to develop composite SASP Factors, and the Factors comprising TNFRI, TNFRII, uPAR, MMP1, GDF15, OPN, Fas, and MPO were significantly altered with CR intervention (age, sex, race-adjusted mixed model time × treatment F = 4.17, p ≤ .05) and associated with the degree of weight loss (R2 = 0.12, p ≤ .05). Our study provides evidence from an RCT that specific circulating biomarkers of senescent cell burden are changed by CR in middle-aged and older adults with obesity and prediabetes. Future studies compare tissue and circulating levels of p16INK4a and pro-inflammatory SASP biomarkers in other populations, and interventions.

Associations between skeletal muscle energetics and accelerometry-based performance fatigability: Study of Muscle, Mobility and Aging.

Performance fatigability is typically experienced as insufficient energy to complete daily physical tasks, particularly with advancing age, often progressing toward dependency. Thus, understanding the etiology of performance fatigability, especially cellular-level biological mechanisms, may help to delay the onset of mobility disability. We hypothesized that skeletal muscle energetics may be important contributors to performance fatigability. Participants in the Study of Muscle, Mobility and Aging completed a usual-paced 400-m walk wearing a wrist-worn ActiGraph GT9X to derive the Pittsburgh Performance Fatigability Index (PPFI, higher scores = more severe fatigability) that quantifies percent decline in individual cadence-versus-time trajectory from their maximal cadence. Complex I&II-supported maximal oxidative phosphorylation (max OXPHOS) and complex I&II-supported electron transfer system (max ETS) were quantified ex vivo using high-resolution respirometry in permeabilized fiber bundles from vastus lateralis muscle biopsies. Maximal adenosine triphosphate production (ATPmax ) was assessed in vivo by 31 P magnetic resonance spectroscopy. We conducted tobit regressions to examine associations of max OXPHOS, max ETS, and ATPmax with PPFI, adjusting for technician/site, demographic characteristics, and total activity count over 7-day free-living among older adults (N = 795, 70-94 years, 58% women) with complete PPFI scores and ≥1 energetics measure. Median PPFI score was 1.4% [25th-75th percentile: 0%-2.9%]. After full adjustment, each 1 standard deviation lower max OXPHOS, max ETS, and ATPmax were associated with 0.55 (95% CI: 0.26-0.84), 0.39 (95% CI: 0.09-0.70), and 0.54 (95% CI: 0.27-0.81) higher PPFI score, respectively. Our findings suggested that therapeutics targeting muscle energetics may potentially mitigate fatigability and lessen susceptibility to disability among older adults.

Validation of the Pittsburgh Performance Fatigability Index in the Study of Muscle, Mobility and Aging.

BACKGROUND: The Pittsburgh Performance Fatigability Index (PPFI) quantifies the percent decline in cadence using accelerometry during standardized walking tasks. Although PPFI has shown strong correlations with physical performance, the developmental sample was relatively homogenous and small, necessitating further validation. METHODS: Participants from the Study of Muscle, Mobility and Aging (N = 805, age = 76.4 ±â€…5.0 years, 58% women, 85% White) wore an ActiGraph GT9X on the nondominant wrist during usual-paced 400 m walk. Tri-axial accelerations were analyzed to compute PPFI (higher score = greater fatigability). To evaluate construct and discriminant validity, Spearman correlations (rs) between PPFI and gait speed, Short Physical Performance Battery (SPPB), chair stand speed, leg peak power, VO2peak, perceived fatigability, and mood were examined. Sex-specific PPFI cut-points that optimally discriminated gait speed using classification and regression tree were then generated. Their discriminate power in relation to aforementioned physical performance were further evaluated. RESULTS: Median PPFI score was 1.4% (25th-75th percentile range: 0%-21.7%), higher among women than men (p < .001). PPFI score was moderate-to-strongly correlated with gait speed (rs = -0.75), SPPB score (rs = -0.38), chair stand speed (rs = -0.36), leg peak power (rs = -0.34) and VO2peak (rs = -0.40), and less strongly with perceived fatigability (rs = 0.28-0.29), all p < .001. PPFI score was not correlated with mood (|rs| < 0.08). Sex-specific PPFI cut-points (no performance fatigability: PPFI = 0%; mild performance fatigability: 0% < PPFI < 3.5% [women], 0% < PPFI < 5.4% [men]; moderate-to-severe performance fatigability: PPFI ≥ 3.5% [women], PPFI ≥ 5.4% [men]) discriminated physical performance (all p < .001), adjusted for demographics and smoking status. CONCLUSION: Our work underscores the utility of PPFI as a valid measure to quantify performance fatigability in future longitudinal epidemiologic studies and clinical/pharmaceutical trials.

Estimating heterogeneity of physical function treatment response to caloric restriction among older adults with obesity.

Clinical trials conventionally test aggregate mean differences and assume homogeneous variances across treatment groups. However, significant response heterogeneity may exist. The purpose of this study was to model treatment response variability using gait speed change among older adults participating in caloric restriction (CR) trials. Eight randomized controlled trials (RCTs) with five- or six-month assessments were pooled, including 749 participants randomized to CR and 594 participants randomized to non-CR (NoCR). Statistical models compared means and variances by CR assignment and exercise assignment or select subgroups, testing for treatment differences and interactions for mean changes and standard deviations. Continuous equivalents of dichotomized variables were also fit. Models used a Bayesian framework, and posterior estimates were presented as means and 95% Bayesian credible intervals (BCI). At baseline, participants were 67.7 (SD = 5.4) years, 69.8% female, and 79.2% white, with a BMI of 33.9 (4.4) kg/m2. CR participants reduced body mass [CR: -7.7 (5.8) kg vs. NoCR: -0.9 (3.5) kg] and increased gait speed [CR: +0.10 (0.16) m/s vs. NoCR: +0.07 (0.15) m/s] more than NoCR participants. There were no treatment differences in gait speed change standard deviations [CR-NoCR: -0.002 m/s (95% BCI: -0.013, 0.009)]. Significant mean interactions between CR and exercise assignment [0.037 m/s (95% BCI: 0.004, 0.070)], BMI [0.034 m/s (95% BCI: 0.003, 0.066)], and IL-6 [0.041 m/s (95% BCI: 0.009, 0.073)] were observed, while variance interactions were observed between CR and exercise assignment [-0.458 m/s (95% BCI: -0.783, -0.138)], age [-0.557 m/s (95% BCI: -0.900, -0.221)], and gait speed [-0.530 m/s (95% BCI: -1.018, -0.062)] subgroups. Caloric restriction plus exercise yielded the greatest gait speed benefit among older adults with obesity. High BMI and IL-6 subgroups also improved gait speed in response to CR. Results provide a novel statistical framework for identifying treatment heterogeneity in RCTs.

Evaluation of a blood-based geroscience biomarker index in a randomized trial of caloric restriction and exercise in older adults with heart failure with preserved ejection fraction.

Intermediate endpoints are needed to evaluate the effect of interventions targeting the biology of aging in clinical trials. A working group identified five blood-based biomarkers that may serve such a purpose as an integrated index. We evaluated the responsiveness of the panel to caloric restriction or aerobic exercise in the context of a randomized clinical trial conducted in patients with heart failure with preserved ejection fraction (HFpEF) with obese phenotype who were predominantly female. Obese HFpEF is highly prevalent in women, and is a geriatric syndrome whose disease pathology is driven by non-cardiac factors and shared drivers of aging. We measured serum Interleukin-6, TNF-α-receptor-I, growth differentiating factor-15, cystatin C, and N-terminal pro-b-type natriuretic peptide at baseline and after 20 weeks in older participants with stable obese HFpEF participating in a randomized, controlled, 2 × 2 factorial trial of caloric restriction and/or aerobic exercise. We calculated a composite biomarker index, summing baseline quintile scores for each biomarker, and analyzed the effect of the interventions on the index and individual biomarkers and their associations with changes in physical performance. This post hoc analysis included 88 randomized participants (71 women [81%]). The mean ± SD age was 66.6 ± 5.3 years, and body mass index (BMI) was 39.3 ± 6.3 kg/m2. Using mixed models, mean values of the biomarker index improved over 20 weeks with caloric restriction (- 0.82 [Formula: see text] 0.58 points, p = 0.05), but not with exercise (- 0.28 [Formula: see text] 0.59 points, p = [Formula: see text]), with no evidence of an interaction effect of CR [Formula: see text] EX [Formula: see text] time (p = 0.80) with adjustment for age, gender, and BMI. At baseline, the biomarker index was inversely correlated with 6-min walk distance, scores on the short physical performance battery, treadmill test peak workload and exercise time to exhaustion (all [Formula: see text] s = between - 0.21 and - 0.24). A reduction in the biomarker index was also associated with increased 4-m usual walk speed ([Formula: see text] s = - 0.31). Among older patients with chronic obese HFpEF, caloric restriction improved a biomarker index designed to reflect biological aging. Moreover, the index was associated with physical performance and exercise tolerance.

Predictors of Clinically Meaningful Gait Speed Response to Caloric Restriction Among Older Adults Participating in Weight Loss Interventions.

BACKGROUND: The purpose of this study was to examine whether select baseline characteristics influenced the likelihood of an overweight/obese, older adult experiencing a clinically meaningful gait speed response (±0.05 m/s) to caloric restriction (CR). METHODS: Individual level data from 1 188 older adults participating in 8, 5/6-month, weight loss interventions were pooled, with treatment arms collapsed into CR (n = 667) or no CR (NoCR; n = 521) categories. Exercise assignment was equally distributed across groups (CR: 65.3% vs NoCR: 65.4%) and did not interact with CR (p = .88). Poisson risk ratios (95% confidence interval [CI]) were used to examine whether CR assignment interacted with select baseline characteristic subgroups: age (≥65 years), sex (female/male), race (Black/White), body mass index (BMI; ≥35 kg/m2), comorbidity (diabetes, hypertension, cardiovascular disease) status (yes/no), gait speed (<1.0 m/s), or inflammatory burden (C-reactive protein ≥3 mg/L, interleukin-6 ≥2.5 pg/mL) to influence achievement of ±0.05 m/s fast-paced gait speed change. Main effects were also examined. RESULTS: The study sample (69.5% female, 80.1% White) was 67.6 ± 5.3 years old with a BMI of 33.8 ± 4.4 kg/m2. Average weight loss achieved in the CR versus NoCR group was -8.3 ± 5.9% versus -1.1 ± 3.8%; p < .01. No main effect of CR was observed on the likelihood of achieving a clinically meaningful gait speed improvement (risk ratio [RR]: 1.09 [95% CI: 0.93, 1.27]) or gait speed decrement (RR: 0.77 [95% CI: 0.57, 1.04]). Interaction effects were nonsignificant across all subgroups. CONCLUSION: The proportion of individuals experiencing a clinically meaningful gait speed change was similar for CR and NoCR conditions. This finding is consistent across several baseline subgroupings.

Incorporating Nutrition, Vests, Education, and Strength Training (INVEST) in Bone Health: Trial Design and Methods.

BACKGROUND: Achievement of 5-10% weight loss (WL) among older adults living with obesity considerably improves prognosis of health-related outcomes; however, concomitant declines in bone mineral density (BMD) limit overall benefit by increasing fracture risk. Declines in mechanical loading contribute to WL-associated BMD loss, with pilot data signaling the addition of external weight replacement (via weighted vest use) during intentional WL mitigates bone loss at weight bearing sites to a similar degree as resistance exercise training (RT). Definitive data in support of weighted vest use as a potential strategy to mitigate WL-associated bone loss in this population are needed. METHODS: In the Incorporating Nutrition, Vests, Education, and Strength Training (INVEST) in Bone Health trial (NCT04076618), 192 older adults (60-85 years) who are overweight (BMI ≥ 27 kg/m2) with at least one obesity-related risk factor or obese (BMI = 30-40 kg/m2) will be randomly assigned to participate in one of three 12-month intervention groups: WL alone, WL + weighted vest use (WL + VEST), or WL + RT. The primary aim is to determine the effects of WL + VEST compared to WL alone and WL + RT on indicators of bone health and subsequent fracture risk. DISCUSSION: Determining effective, translatable strategies that minimize bone loss during intentional WL among older adults holds public health potential. The INVEST in Bone Health trial offers an innovative approach for increasing mechanical stress during intentional WL in the absence of RT. If successful, findings from this study will provide evidence in support of a scalable solution to minimize bone loss during intentional WL among older adults with obesity.

Inflammatory biomarkers, geriatric assessment, and treatment outcomes in acute myeloid leukemia.

OBJECTIVES: To investigate changes in inflammatory biomarkers during induction therapy for older adults with acute myeloid leukemia (AML) and their associations with geriatric assessment (GA) measures and outcomes. METHODS: This was a single institution ancillary study to a prospective observational study (N = 20 consecutive adults aged ≥60 with newly diagnosed AML who received induction chemotherapy). Biomarkers (Interleukin-6 [IL-6], IL-6 soluble receptor [IL-6 sR], tumor necrosis factor alpha [TNFα], TNFα soluble receptor 1 [TNFα sR1], interleukin-3 [IL-3], C-reactive protein [CRP]) were collected at start of induction, weekly for three weeks, and post-induction and were compared over time using paired t-tests. GA was administered at baseline and post-induction, and correlated with biomarker levels using Spearman correlations. Survival was estimated using Kaplan-Meier and compared by categorized biomarker level using Wilcoxon tests. RESULTS: Biomarker levels were stable during induction, except for CRP and IL-6 sR. Declines in objectively measured physical function [Short Physical Performance Battery (SPPB); r = 0.71, p < 0.01] and increases in self-reported limitation in instrumental activities of daily living (r = 0.81, p < 0.01) were correlated with increased TNFα sR1. Declines in SPPB were correlated with increased CRP (r = -0.73, p < 0.01). Improvement in depression was correlated with increased IL-6 sR (r = -0.59 p = 0.02). Survival was shorter in those with baseline TNFα or CRP levels above the median (6.1 vs. 40.2 months and 5.5 vs. 27.6 months respectively, p = 0.04 for both). CONCLUSION: Among older adults with AML, the relationships between TNFα sR1, CRP, and IL-6 sR with change in physical and emotional health during treatment warrants further investigation.

Association of Symptoms of Obstructive Lung Disease and All-Cause Mortality in Older Adult Smokers.

OBJECTIVES: This study aims to investigate the impact of respiratory symptoms in current and former smokers with and without obstructive lung disease (OLD) on all-cause mortality. DESIGN: Secondary analysis in a prospective cohort (the Health, Aging and Body Composition study). SETTING: Memphis, Tennessee, and Pittsburgh, Pennsylvania. PARTICIPANTS: Black and white men and women with a history of current and former smoking (N = 596; 63% male and 37% female) aged 70-79 years followed for 13 years. Participants were categorized into 4 mutually exclusive groups based on symptom profile and forced expiratory volume in the 1st second to forced vital capacity ratio. The groups were Less Dyspnea-No OLD (N = 196), More Dyspnea-No OLD (N = 104), Less Dyspnea-With OLD (N = 162), and More Dyspnea-With OLD (N = 134). MEASUREMENTS: All-cause mortality. RESULTS: Overall, 53% in Less Dyspnea-No OLD, 63% in More Dyspnea-No OLD, 67% in Less Dyspnea-With OLD, and 84% in More Dyspnea-With OLD died within the 13- year follow up period (log-rank χ2 = 44.4, P < .0001). The hazard ratio was highest for participants with OLD, both with (HR =1.91, 95% CI 1.44 - 2.54; P < .0001) and without dyspnea (HR = 1.52, 95% CI 1.15 - 2.02; p = .004). Participants without OLD but with dyspnea had a similar risk of death to subjects who had OLD but fewer symptoms. CONCLUSIONS: OLD is associated with high risk of death with different risk profiles based on symptom group. Patients with symptoms of shortness of breath without OLD should be considered an at-risk group given their similar mortality to those with OLD with minimal symptoms. J Am Geriatr Soc 67:2116-2122, 2019.

Cellular Senescence Biomarker p16INK4a+ Cell Burden in Thigh Adipose is Associated With Poor Physical Function in Older Women.

Background: Ample evidence implicates cellular senescence as a contributor to frailty and functional decline in rodents, but considerable effort remains to translate these findings to human aging. Methods: We quantified senescence biomarker p16INK4a-expressing cells in thigh adipose tissue obtained from older women previously enrolled in a 5-month resistance training intervention, with or without caloric restriction (RT ± CR, n = 11 baseline, 8 pre-post-intervention pairs). Women in this subsample were older (72.9 ± 3.4 y) and overweight/obese (body mass index: 30.6 ± 2.4 kg/m2). p16INK4a+ cells were identified from 12 to 20 random visual fields/sample at 20× magnification (immunohistochemical, nuclear staining) and were present in all adipose samples. Results: Cross-sectional associations were observed between p16INK4a+ cell burden and physical function, including grip strength (r = -0.74), 400-m walk time (r = 0.74), 4-m gait speed (r = -0.73), and self-perceived mobility (r = -0.78) (p ≤ .05). These relationships remained significant after independent adjustments for age and adiposity (p ≤ .05). p16INK4a+ cell abundance was lower following the intervention (pre: 5.47 ± 3.4%, post: 2.17 ± 1.1% count p16INK4a+ cells, p ≤ .05). Conclusions: These results provide proof-of-concept that p16INK4a+ cells in thigh adipose are associated with physical function, and may be sensitive to change with RT ± CR in overweight/obese older women.

Racial differences in circulating levels of the soluble receptor for advanced glycation endproducts in middle-aged and older adults.

BACKGROUND: Low levels of the soluble receptor for advanced glycation endproducts (sRAGE) have been implicated in a number of chronic diseases. Previous studies indicate that sRAGE levels are ~30% lower in Blacks compared to Whites. However, the reasons for these differences are unclear. PURPOSE: We aimed to identify predictors of circulating sRAGE biomarkers among Black and White adults at high cardiac risk. METHODS: Serum levels of total sRAGE, endogenous secretory RAGE (esRAGE), carboxymethyl-lysine (CML, a major RAGE ligand), and their ratios were measured in 99 Blacks and 454 Whites. RESULTS: Blacks had a more adverse cardiovascular risk profile, as well as lower median levels of total sRAGE (972 vs. 1564pg/ml) and esRAGE (474 vs. 710pg/ml) compared to Whites (p<0.0001). In addition, the proportion of esRAGE was higher in Blacks (47% vs. 44%, p=0.02), as were the CML/total sRAGE (0.89 vs. 0.56ng/pg) and CML/esRAGE (1.72 vs. 1.20ng/pg) ratios (p<0.0001). Racial differences persisted after adjustment for key covariates including age, gender, tobacco use, comorbidities, BMI, blood pressure, glucose, insulin, triglycerides, C-reactive protein, and renal function (p<0.05). Race alone accounted for nearly half of the variability in total sRAGE levels (10.6%; model explained 23.9%). In stratified analyses, gender and heart rate were independently associated with total sRAGE and esRAGE in Whites, while CML and C-reactive protein were associated with total sRAGE in Blacks. CONCLUSIONS: We identified several independent predictors of sRAGE biomarkers. Notably, Black race was associated with an adverse AGE/RAGE profile, including lower sRAGE and higher CML/sRAGE ratios.

Relationship of Objectively-Measured Habitual Physical Activity to Chronic Inflammation and Fatigue in Middle-Aged and Older Adults.

BACKGROUND: Habitual (non-exercise) physical activity (PA) declines with age, and aging-related increases in inflammation and fatigue may be important contributors to variability in PA. METHODS: This study examined the association of objectively-measured PA (accelerometry over 7 days) with inflammation (plasma interleukin-6 and C-reactive protein) and with self-reported fatigue (SF-36 Vitality) at baseline and 18 months after a diet-induced weight loss, exercise, or diet-induced weight loss plus exercise intervention in 167 overweight/obese, middle-aged, and older adults. RESULTS: At baseline, individuals with higher plasma interleukin-6, as well as those who reported feeling less energetic (more fatigued), took less steps per day and had lower PA energy expenditure and minutes of light and moderate-vigorous PA (p < .05 for all). At the 18-month follow-up, inflammation was lower in both weight loss groups, fatigue was reduced in all three groups with larger decreases in the combined group, and mean levels of habitual PA were not changed in any group. In longitudinal analyses with all groups combined, we found that participants reporting larger increases in vitality (eg, declines in fatigue) had greater increases in PA (p < .05 for all). Also, changes in steps/d and physical activity energy expenditure were indirectly associated with changes in interleukin-6 (ß [SEM] for steps/d = -565 [253]; ß [SEM] for physical activity energy expenditure = -22.4 [10.17]; p < .05). CONCLUSIONS: Levels of habitual PA are lower in middle-aged and older adults with higher levels of chronic inflammation and greater self-reported fatigue. In addition, participants who experienced greater declines in inflammation during the interventions had greater declines in fatigue and larger increases in PA.

A brief yoga intervention implemented during chemotherapy: A randomized controlled pilot study.

OBJECTIVES: Fatigue and other treatment-related symptoms (e.g., sleep disturbance) are critical targets for improving quality of life in patients undergoing chemotherapy. Yoga may reduce the burden of such symptoms. This study investigated the feasibility of conducting a randomized controlled study of a brief yoga intervention during chemotherapy for colorectal cancer. DESIGN: We randomized adults with colorectal cancer to a brief Yoga Skills Training (YST) or an attention control (AC; empathic attention and recorded education). SETTING: The interventions and assessments were implemented individually in the clinic while patients were in the chair receiving chemotherapy. INTERVENTIONS: Both interventions consisted of three sessions and recommended home practice. MAIN OUTCOME MEASURES: The primary outcome was feasibility (accrual, retention, adherence, data collection). Self-reported outcomes (i.e., fatigue, sleep disturbance, quality of life) and inflammatory biomarkers were also described to inform future studies. RESULTS: Of 52 patients initially identified, 28 were approached, and 15 enrolled (age Mean = 57.5 years; 80% White; 60% Male). Reasons for declining participation were: not interested (n = 6), did not perceive a need (n = 2), and other (n = 5). Two participants were lost to follow-up in each group due to treatment changes. Thus, 75% of participants were retained in the YST and 71% in the AC arm. Participants retained in the study adhered to 97% of the in-person intervention sessions and completed all questionnaires. CONCLUSIONS: This study demonstrated the feasibility of conducting a larger randomized controlled trial to assess YST among patients receiving chemotherapy for colorectal cancer. Data collected and challenges encountered will inform future research.

Blood-cell bioenergetics are associated with physical function and inflammation in overweight/obese older adults.

BACKGROUND: Physical function and strength decline with age and lead to limited mobility and independence in older adults. Alterations in mitochondrial function are thought to underlie numerous age-related changes, including declining physical ability. Recent studies suggest that systemic changes in bioenergetic capacity may be reported by analyzing mitochondrial function in circulating cells. The objective of this study was to determine whether the bioenergetic capacity of peripheral blood mononuclear cells (PBMCs) is related to differences in physical function among older, overweight/obese, adults. To address this, we tested the hypothesis that greater PBMC respirometric capacity would be associated with better physical function, muscular strength, leg lean mass, and muscle quality. Furthermore, we tested whether the respirometric capacity of PBMCs is related to cellular composition and inflammatory status reported by interleukin-6 (IL-6). METHODS: Fasted PBMC respiration (pmol/min/500,000 cells), expanded short physical performance battery (Ex-SPPB), peak knee extensor (KE) strength (Nm), grip strength (kg), leg lean mass (kg, via dual energy X-ray absorptiometry [DXA]), muscle quality (Nm/kg), and plasma IL-6 (pg/mL) were analyzed in 15 well-functioning, community-dwelling, sedentary overweight/obese older men (n=9) and women (n=6) aged 65 to 78 (mean 68.3 ± 3.5 years). Pearson and partial correlations were calculated to determine associations between PBMC respiration and these variables. RESULTS: Higher maximal respiration of PBMCs was associated with better Ex-SPPB (r=0.58, p=0.02), greater KE strength (r=0.60, p=0.02), greater grip strength (r=0.52, p=0.05) and lower IL-6 (r=-0.58, p=0.04). Higher spare respiratory capacity was associated with better Ex-SPPB (r=0.59, p=0.02), greater KE strength (r=0.60, p=0.02), greater grip strength (r=0.54, p=0.04), greater leg muscle quality (r=0.56, p=0.04), and lower IL-6 (r=-0.55, p=0.05). Monocyte and lymphocyte counts were not related to PBMC respiratory capacity. CONCLUSIONS: Our results indicate that respirometric profiles of readily obtainable blood cells are associated with physical function and strength. Future studies should be undertaken in order to determine whether blood-based bioenergetic profiling can provide an objective index of systemic mitochondrial health.

Regional adipose tissue hormone/cytokine production before and after weight loss in abdominally obese women.

OBJECTIVE: To compare the regional differences in subcutaneous adipose tissue hormone/cytokine production in abdominally obese women during weight loss. METHODS: Forty-two abdominally obese, older women underwent a 20-week weight loss intervention composed of hypocaloric diet with or without aerobic exercise (total energy expenditure: ∼2800 kcal/week). Subcutaneous (gluteal and abdominal) adipose tissue biopsies were conducted before and after the intervention. Adipose tissue gene expression and release of leptin, adiponectin, and interleukin 6 (IL-6) were determined. RESULTS: The intervention resulted in significant weight loss (-10.1 ± 0.7 kg, P < 0.001). At baseline, gene expression of adiponectin were higher (P < 0.01), and gene expression and release of IL-6 were lower (both P < 0.05) in abdominal than in gluteal adipose tissue. After intervention, leptin gene expression and release were lower in both gluteal and abdominal adipose tissue compared to baseline (P < 0.05-0.01). Abdominal, but not gluteal, adipose tissue adiponectin gene expression and release increased after intervention (both P < 0.05). CONCLUSION: A 20-week weight loss program decreased leptin production in both gluteal and abdominal adipose tissue, but only increased adiponectin production from abdominal adipose tissue in obese women. This depot-specific effect may be of importance for the treatment of health complications associated with abdominal adiposity.

Effect of an 18-month physical activity and weight loss intervention on body composition in overweight and obese older adults.

OBJECTIVE: Our primary objective was to determine the long-term effects of physical activity (PA) and weight loss (WL) on body composition in overweight/obese older adults. Secondarily, the association between change in body mass and composition on change in several cardiometabolic risk factors and mobility was evaluated. DESIGN AND METHODS: 288 older (X ± SD: 67.0 ± 4.8 years), overweight/obese (BMI 32.8 ± 3.8 kg/m² ) men and women participated in this 18-month randomized, controlled trial. Treatment groups included PA + WL (n = 98), PA-only (n = 97), and a successful aging (SA) health education control (n = 93). DXA-acquired body composition measures (total body fat and lean mass), conventional biomarkers of cardiometabolic risk, and 400-m walk time were obtained at baseline and 18 months. RESULTS: Fat mass was significantly reduced from (X ± SE) 36.5 ± 8.9 kg to 31.7 ± 9.0 kg in the PA + WL group (p < 0.01), but remained unchanged from baseline in the PA-only (-0.8 ± 3.8 kg) and SA (-0.0 ± 3.9 kg) group. Lean mass losses were three times greater in the PA + WL groups compared to PA-only or SA groups (-2.5 ± 2.8 kg vs. -0.7 ± 2.2 kg or -0.8 ± 2.4 kg, respectively; p < 0.01); yet due to a larger decrease in fat mass, percent lean mass was significantly increased over baseline in the PA + WL groups (2.1% ± 2.6%; p < 0.01). Fat mass loss was primarily responsible for WL-associated improvements in cardiometabolic risk factors, while reduction in body weight, regardless of compartment, was significantly associated with improved mobility. CONCLUSION: This 18-month PA + WL program resulted in a significant reduction in percent body fat with a concomitant increase in percent body lean mass. Shifts in body weight and composition were associated with favorable changes in clinical parameters of cardiometabolic risk and mobility. Moderate PA without WL had no effect on body composition.

Effects of intensive diet and exercise on knee joint loads, inflammation, and clinical outcomes among overweight and obese adults with knee osteoarthritis: the IDEA randomized clinical trial.

IMPORTANCE: Knee osteoarthritis (OA), a common cause of chronic pain and disability, has biomechanical and inflammatory origins and is exacerbated by obesity. OBJECTIVE: To determine whether a ≥10% reduction in body weight induced by diet, with or without exercise, would improve mechanistic and clinical outcomes more than exercise alone. DESIGN, SETTING, AND PARTICIPANTS: Single-blind, 18-month, randomized clinical trial at Wake Forest University between July 2006 and April 2011. The diet and exercise interventions were center-based with options for the exercise groups to transition to a home-based program. Participants were 454 overweight and obese older community-dwelling adults (age ≥55 years with body mass index of 27-41) with pain and radiographic knee OA. INTERVENTIONS: Intensive diet-induced weight loss plus exercise, intensive diet-induced weight loss, or exercise. MAIN OUTCOMES AND MEASURES: Mechanistic primary outcomes: knee joint compressive force and plasma IL-6 levels; secondary clinical outcomes: self-reported pain (range, 0-20), function (range, 0-68), mobility, and health-related quality of life (range, 0-100). RESULTS: Three hundred ninety-nine participants (88%) completed the study. Mean weight loss for diet + exercise participants was 10.6 kg (11.4%); for the diet group, 8.9 kg (9.5%); and for the exercise group, 1.8 kg (2.0%). After 18 months, knee compressive forces were lower in diet participants (mean, 2487 N; 95% CI, 2393 to 2581) compared with exercise participants (2687 N; 95% CI, 2590 to 2784, pairwise difference [Δ](exercise vs diet )= 200 N; 95% CI, 55 to 345; P = .007). Concentrations of IL-6 were lower in diet + exercise (2.7 pg/mL; 95% CI, 2.5 to 3.0) and diet participants (2.7 pg/mL; 95% CI, 2.4 to 3.0) compared with exercise participants (3.1 pg/mL; 95% CI, 2.9 to 3.4; Δ(exercise vs diet + exercise) = 0.39 pg/mL; 95% CI, -0.03 to 0.81; P = .007; Δ(exercise vs diet )= 0.43 pg/mL; 95% CI, 0.01 to 0.85, P = .006). The diet + exercise group had less pain (3.6; 95% CI, 3.2 to 4.1) and better function (14.1; 95% CI, 12.6 to 15.6) than both the diet group (4.8; 95% CI, 4.3 to 5.2) and exercise group (4.7; 95% CI, 4.2 to 5.1, Δ(exercise vs diet + exercise) = 1.02; 95% CI, 0.33 to 1.71; P(pain) = .004; 18.4; 95% CI, 16.9 to 19.9; Δ(exercise vs diet + exercise), 4.29; 95% CI, 2.07 to 6.50; P(function )< .001). The diet + exercise group (44.7; 95% CI, 43.4 to 46.0) also had better physical health-related quality of life scores than the exercise group (41.9; 95% CI, 40.5 to 43.2; Δ(exercise vs diet + exercise) = -2.81; 95% CI, -4.76 to -0.86; P = .005). CONCLUSIONS AND RELEVANCE: Among overweight and obese adults with knee OA, after 18 months, participants in the diet + exercise and diet groups had more weight loss and greater reductions in IL-6 levels than those in the exercise group; those in the diet group had greater reductions in knee compressive force than those in the exercise group. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00381290.

Independent and combined effects of physical activity and weight loss on inflammatory biomarkers in overweight and obese older adults.

OBJECTIVES: To determine the independent effect of long-term physical activity (PA) and the combined effects of long-term PA and weight loss (WL) on inflammation in overweight and obese older adults. DESIGN: Eighteen-month randomized, controlled trial. SETTING: The community infrastructure of cooperative extension centers. PARTICIPANTS: Overweight and obese (body mass index >28.0 kg/m(2) ) community-dwelling men and women aged 60 to 79 at risk for cardiovascular disease (CVD). INTERVENTION: Physical activity + weight loss (PA + WL) (n = 98), PA only (n = 97), or successful aging (SA) health education (n = 93) intervention. MEASUREMENTS: Biomarkers of inflammation (adiponectin, leptin, high-sensitivity interleukin (hsIL)-6, IL-6sR, IL-8, and soluble tumor necrosis factor receptor 1) were measured at baseline and 6 and 18 months. RESULTS: After adjustment for baseline biomarker, wave, sex, and visit, leptin and hsIL-6 showed a significant intervention effect. Specifically, leptin was significantly lower in the PA + WL group (21.3 ng/mL, 95% confidence interval (CI) = 19.7-22.9 ng/mL) than in the PA (29.3 ng/mL, 95% CI = 26.9-31.8 ng/mL) or SA (30.3 ng/mL, 95% CI = 27.9-32.8 ng/mL) group (both P < .001), and hsIL-6 was significantly lower in the PA + WL group (2.1 pg/mL, 95% CI = 1.9-2.3 pg/mL) than in the PA (2.5 pg/mL, 95% CI = 2.3-2.7 pg/mL) or SA (2.4 pg/mL, 95% CI = 2.2-2.6 pg/mL) group (P = .02). CONCLUSION: Addition of dietary-induced WL to PA reduced leptin and hsIL-6 more than PA alone and more than a SA intervention in older adults at risk for CVD. Results suggest that WL, rather than increased PA, is the lifestyle factor primarily responsible for improvement in the inflammatory profile.

Lipopolysaccharide-binding protein, a surrogate marker of microbial translocation, is associated with physical function in healthy older adults.

BACKGROUND: Physical function declines, and markers of inflammation increase with advancing age, even in healthy persons. Microbial translocation (MT) is the systemic exposure to mucosal surface microbes/microbial products without overt bacteremia and has been described in a number of pathologic conditions. We hypothesized that markers of MT, soluble CD14 (sCD14) and lipopolysaccharide (LPS) binding protein (LBP), may be a source of chronic inflammation in older persons and be associated with poorer physical function. METHODS: We assessed cross-sectional relationships among two plasma biomarkers of MT (sCD14 and LBP), physical function (hand grip strength, short physical performance battery [SPPB], gait speed, walking distance, and disability questionnaire), and biomarkers of inflammation (C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), TNF-α soluble receptor 1 [TNFsR1]) in 59 older (60-89 years), healthy (no evidence of acute or chronic illness) men and women. RESULTS: LBP was inversely correlated with SPPB score and grip strength (p = .02 and p < .01, respectively) and positively correlated with CRP (p = 0.04) after adjusting for age, gender, and body mass index. sCD14 correlated with IL-6 (p = .01), TNF-α (p = .05), and TNFsR1 (p < .0001). Furthermore, the correlations between LBP and SPPB and grip strength remained significant after adjusting for each inflammatory biomarker. CONCLUSIONS: In healthy older individuals, LBP, a surrogate marker of MT, is associated with worse physical function and inflammation. Additional study is needed to determine whether MT is a marker for or a cause of inflammation and the associated functional impairments.

Total and abdominal adiposity are associated with inflammation in older adults using a factor analysis approach.

BACKGROUND: Obesity-related increases in multiple inflammatory markers may contribute to the persistent subclinical inflammation common with advancing age. However, it is unclear if a specific combination of markers reflects the underlying inflammatory state. We used factor analysis to identify inflammatory factor(s) and examine their associations with adiposity in older adults at risk for disability. METHODS: Adiponectin, CRP, IL-1ra, IL-1sRII, IL-2sRα, IL-6, IL-6sR, IL-8, IL-15, sTNFRI, sTNFRII, and TNF-α were measured in 179 participants from the Lifestyle Interventions and Independence for Elders Pilot (Mean ± SD age 77 ± 4 years, 76% white, 70% women). Body mass index, waist circumference, and total fat mass were assessed by anthropometry and dual-energy x-ray absorptiometry. RESULTS: IL-2sRα, sTNFRI, and sTNFRII loaded highest on the first factor (factor 1). CRP, IL-1ra, and IL-6 loaded highest on the second factor (factor 2). Factor 2, but not factor 1, was positively associated with 1-SD increments in waist circumference (ß = 0.160 ± 0.057, p = .005), body mass index (ß = 0.132 ± 0.053, p = .01), and total fat mass (ß = 0.126 ± 0.053, p = .02) after adjusting for age, gender, race/ethnicity, site, smoking, anti-inflammatory medications, comorbidity index, health-related quality of life, and physical function. These associations remained significant after further adjustment for grip strength, but only waist circumference remained associated with inflammation after adjusting for total lean mass. There were no significant interactions between adiposity and muscle mass or strength for either factor. CONCLUSIONS: Greater total and abdominal adiposity are associated with higher levels of an inflammatory factor related to CRP, IL-1ra, and IL-6 in older adults, which may provide a clinically useful measure of inflammation in this population.