Associations between Circulating Inflammatory Biomarkers and Indicators of Muscle Health in Older Men and Women.

Systemic inflammation is believed to contribute to declining muscle health during aging. The present study aims to examine associations between indicators of muscle health and pro- and anti-inflammatory biomarkers in older men and women, while also considering the impacts of physical activity and protein intake. An assessment of skeletal muscle index (SMI) by bioelectrical impedance analysis, handgrip strength, and 5-sit-to-stand time, using standardized procedures, was conducted in a population of older men (n = 90) and women (n = 148) aged 65-70 years. The inflammatory biomarkers C-reactive protein (CRP), fibrinogen, interleukin (IL)-6, IL-10, IL-18, tumor necrosis factor (TNF)-α, monocyte chemoattractant protein-1, and macrophage inflammatory protein-1α were assessed in blood samples. Data were analyzed and stratified according to biological sex using multiple linear regression models. In older women, SMI was inversely associated with the pro-inflammatory markers CRP (ß = -0.372; p < 0.05), fibrinogen (ß = -0.376; p < 0.05), and IL-6 (ß = -0.369; p < 0.05). Importantly, these associations were independent of abdominal adiposity (waist circumference), protein intake, physical activity level, as well as any adherence to muscle strengthening guidelines (≥2 sessions/week). In contrast, no corresponding associations were observed in men. In conclusion, our findings indicate the detrimental influence of a pro-inflammatory environment on muscle health regardless of important lifestyle-related factors in older women. However, the lack of such associations in older men highlights the importance of considering biological sex when examining the complex interaction between the systemic inflammatory environment and muscle health.

Randomized Controlled Trial for Promotion of Healthy Eating in Older Adults by Increasing Consumption of Plant-Based Foods: Effect on Inflammatory Biomarkers.

To what extent the intake of fruit and vegetables (FV) influences inflammatory status remains elusive, particularly in older populations. The aim of the present study was to determine the effect of increased FV intake for 16 weeks on circulating biomarkers of inflammation in a population of older men and women. Sixty-six participants (65-70 years) randomly assigned to either FV or control (CON) groups were instructed to increase FV intake to five servings per day through nutritional counseling (FV) or to maintain habitual diet (CON). Dietary intake and physical activity level (PA) were determined using food frequency questionnaire and accelerometers, respectively, at the start and end of the intervention. C-reactive protein (CRP), interleukin 6 (IL-6), IL-18, macrophage inflammatory protein-1α (MIP-1α), MIP-1ß, tumor necrosis factor-α (TNF-α), TNF-related apoptosis-inducing ligand (TRAIL), TNF-related activation-induced cytokine (TRANCE), and C-X3-C motif chemokine ligand-1 (CX3CL1, or fractalkine) were analyzed. The FV group significantly increased daily FV intake (from 2.2 ± 1.3 to 4.2 ± 1.8 servings/day), with no change in CON. Waist circumference and PA level were unchanged by the intervention. Interaction effects (time × group, p < 0.05) for TRAIL, TRANCE, and CX3CL1 denoting a significant decrease (p < 0.05) in FV but not in CON were observed. No corresponding effects on CRP, IL6, TNF-α, MIP-1α, and ß and IL-18 were observed. The present study demonstrates the influence of increased FV consumption on levels of some inflammatory biomarkers in a population of older adults. Future work is warranted to examine the clinical implications of FV-induced alterations in these inflammatory biomarkers.

Sedentary Patterns and Systemic Inflammation: Sex-Specific Links in Older Adults.

The study aimed to examine sex-specific associations between objectively measured sedentary patterns and pro- and anti-inflammatory biomarkers in older adults when considering the moderating impact of physical activity (PA). Accelerometer-based monitoring of sedentary patterns and PA was conducted in a population of older men (n = 83; age: 67.4 ± 1.5; height: 178.7 ± 6.6 cm; weight: 80.9 ± 10.6 kg) and women (n = 146; age: 67.4 ± 1.6; height: 164.2 ± 6.1 cm; weight: 64.6 ± 10.1 kg) aged 65-70. Blood samples were collected for the assessment of the inflammatory biomarkers C-reactive protein (CRP), fibrinogen, interleukin-6 (IL-6), IL-10, IL-18, and monocyte chemoattractant protein-1 (MCP-1). Data were analyzed using multiple linear regression models. Total and bouts of ≥10 min of sedentary time were inversely associated with the anti-inflammatory marker IL-10 in older men (accumulated sedentary time: ß = -0.116; bouts: ß = -0.099; all p < 0.05). Associations were independent of moderate-to-vigorous physical activity (MVPA) and total PA volume. In women, total and bouts of ≥10 min of sedentary time were detrimentally associated with the pro-inflammatory marker fibrinogen (accumulated sedentary time: ß = -0.130; bouts: ß = -0.085; all p < 0.05). Associations remained between accumulated sedentary time and fibrinogen when adjusting for MVPA and total PA volume. This study highlights sex-specific routes by which sedentary patterns impact on pro- and anti-inflammatory biomarkers in older adults. The findings support efforts to promote accumulation of time spent in PA at the expense of time in sedentary pursuits on low-grade inflammation in older men and women.

Impact of healthy diet and physical activity on metabolic health in men and women: Study Protocol Clinical Trial (SPIRIT Compliant).

INTRODUCTION: Healthy dietary patterns and physical activity (PA) represent important lifestyle behaviors with considerable potential to influence on age-related metabolic health. Yet, data on the combined effects of these lifestyle behaviors on metabolic health including low-grade systemic inflammation in aging populations remain scarce. Therefore, this protocol describes a randomized controlled trial aiming to examine the impacts of healthy dietary patterns alone or combined with PA on metabolic health in middle-aged and older men and women. MATERIAL AND METHODS: The ORUDIET study is a 3-arm randomized controlled 16-week trial: Healthy Diet (HD), Healthy diet plus PA (HD-PA), and control (CON). The trial is open label, randomized with allocation concealment, parallel groups with passive controls. Participants without overt disease aged between 55 and 70 years, with BMI below 35, a current intake of a maximum of 1 serving of fruit and vegetable per day, and noncompliance to PA guidelines are eligible for inclusion. Participants in HD are instructed to increase fruit and vegetable intake to 5 servings per day (equivalent to 500 g). Participants in HD-PA receive the same dietary intervention as the HD and are additionally instructed to engage in moderate-to-vigorous physical activities for at least 150 minutes per week. The primary study outcomes are changes in metabolic and inflammatory health biomarkers. Secondary outcomes are changes in body composition and perceived health. ETHICS AND DISSEMINATION: The study protocol has been approved by the ethical review board in Uppsala, Sweden. The results will be published in peer-reviewed journals and disseminated in national and international conferences. TRIAL REGISTRATION NUMBER: NCT04062682 Pre-results.

Cardiorespiratory Fitness Does Not Offset Adiposity-Related Systemic Inflammation in Physically Active Older Women.

CONTEXT: Chronic inflammation increases diabetes risk and may be exacerbated by excess adipose tissue. Whether cardiovascular fitness can offset chronic inflammation associated with excess adipose tissue in older adults is unclear. OBJECTIVE: The study aimed to examine the influence of cardiorespiratory fitness on links between adiposity and pro- and anti-inflammatory biomarkers related to metabolic risk in physically active older women. DESIGN, SETTING, AND PARTICIPANTS: Cross-sectional study comprising older community-dwelling women (n = 109; age, 65 to 70 years). MAIN OUTCOME: Cardiorespiratory fitness was assessed using a standardized submaximal test and participants were categorized into high- and low-adiposity-related metabolic risk [body mass index, waist-to-hip ratio (WHR), and total fat mass]. The inflammatory biomarkers C-reactive protein (CRP), IL-6, IL-10, IL-18, adiponectin, monocyte chemoattractant protein-1 (MCP-1), and macrophage inflammatory protein (MIP)-1α were analyzed. RESULTS: Regardless of adiposity measure, women in the metabolic high-risk group had substantially elevated (P < 0.05) CRP and lower adiponectin levels. Levels of IL-6 and MIP1-α were elevated in the high-risk group defined by WHR and total fat mass. The IL-18 level was elevated in the high-risk group based on WHR only. Importantly, a high cardiorespiratory fitness level did not attenuate the detrimental links between adiposity measures and inflammation. CONCLUSIONS: Cardiorespiratory fitness does not offset the detrimental links between adiposity and several inflammatory biomarkers related to metabolic risk in physically active older women. Reducing abdominal adipose tissue in older adults should be emphasized in efforts aiming to attenuate age-related systemic inflammation and metabolic risk regardless of cardiorespiratory fitness.

Physical Activity Alters Inflammation in Older Adults by Different Intensity Levels.

PURPOSE: To examine the influence of reallocating time spent at different objectively measured physical activity (PA) behaviors on markers of systemic inflammation in older women with different levels of metabolic risk. METHODS: Accelerometer-based monitoring of PA was conducted in a population of community-dwelling older women (n = 111; age, 65-70 yr) for determination of daily sedentary time, time in light PA (LPA) and moderate-to-vigorous PA (MVPA). Blood samples were collected for the assessment of the systemic inflammatory markers C-reactive protein (CRP), fibrinogen, and adiponectin. Metabolic risk was assessed by standardized procedures based on definitions for the metabolic syndrome. Data were analyzed by linear regression models based on isotemporal substitution analysis. RESULTS: Reallocating 30 min of sedentary time with either time in LPA (ß = -0.47; P < 0.05) or MVPA (ß = -0.42; P < 0.05) was related to reduced fibrinogen level, whereas no corresponding effect was evident when shifting time in LPA with time in MVPA, while holding sedentary time constant. In contrast, reallocating a 30-min period in sedentary (ß = -0.70; P < 0.01) or LPA (ß = -0.71; P < 0.01) with MVPA was associated with a significant reduction in CRP level, whereas no impact on CRP was observed when a period of sedentary behavior was replaced with LPA. Importantly, all significant influences on fibrinogen and CRP by displacement of different PA behaviors remained after adjustment for metabolic risk status among participants. No significant associations with adiponectin were observed. CONCLUSIONS: Altogether, this work supports the existence of different intensity thresholds mediating beneficial effects of PA on important clinical markers of systemic inflammation in older women across different stages of disease prevention.