Resting metabolic rate and skeletal muscle SERCA and Na
            +
            /K
            +
            ATPase activities are not affected by fish oil supplementation in healthy older adults

Abstract Context African American women (AAW) have a higher incidence of insulin resistance and are at a greater risk for the development of obesity and type 2 diabetes than Caucasian women (CW). Although several factors have been proposed to mediate these racial disparities, the mechanisms remain poorly defined. We previously demonstrated that sedentary lean AAW have lower peripheral insulin sensitivity, reduced maximal aerobic fitness (VO2max), and lower resting metabolic rate (RMR) than CW. We have also demonstrated that skeletal muscle mitochondrial respiration is lower in AAW and appears to play a role in these racial differences. Objective The goal of this study was to assess mitochondrial pathways and dynamics to examine the potential mechanisms of lower insulin sensitivity, RMR, VO2max, and mitochondrial capacity in AAW. Design To achieve this goal, we assessed several mitochondrial pathways in skeletal muscle using gene array technology and semiquantitative protein analysis. Results We report alterations in mitochondrial pathways associated with inner membrane small molecule transport genes, fusion–fission, and autophagy in lean AAW. These differences were associated with lower insulin sensitivity, RMR, and VO2max. Conclusions Together these data suggest that the metabolic racial disparity of insulin resistance, RMR, VO2max, and mitochondrial capacity may be mediated by perturbations in mitochondrial pathways associated with membrane transport, fission–fusion, and autophagy. The mechanisms contributing to these differences remain unknown.

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Effects of Supplemental Fish Oil on Resting Metabolic Rate and Body Composition in Middle-Aged Adults

Medicine & Science in Sports & Exercise ◽

10.1249/01.mss.0000384983.26782.27 ◽

2010 ◽

Vol 42 ◽

pp. 438

Author(s):

Eric E. Noreen ◽

Michael J. Sass ◽

Lindsay K. Averill

Keyword(s):

Body Composition ◽

Metabolic Rate ◽

Fish Oil ◽

Resting Metabolic Rate ◽

Middle Aged ◽

Middle Aged Adults

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An Exploratory Analysis of Changes in Mental Wellbeing Following Curcumin and Fish Oil Supplementation in Middle-Aged and Older Adults

Nutrients ◽

10.3390/nu12102902 ◽

2020 ◽

Vol 12 (10) ◽

pp. 2902

Author(s):

Julia C. Kuszewski ◽

Peter R. C. Howe ◽

Rachel H. X. Wong

Keyword(s):

Older Adults ◽

Fish Oil ◽

Mood States ◽

Exploratory Analysis ◽

Mental Wellbeing ◽

Subjective Memory ◽

Double Blind ◽

Fish Oil Supplementation ◽

Plasma Apolipoprotein

Curcumin has previously been shown to enhance mood in non-depressed older adults. However, observed benefits were limited to short-term supplementation (4 weeks). In a 16 week randomized, double-blind, placebo-controlled, 2 × 2 factorial design trial, we supplemented overweight or obese non-depressed adults (50–80 years) with curcumin (160 mg/day), fish oil (2000 mg docosahexaenoic acid +400 mg eicosapentaenoic acid/day), or a combination of both. Secondary outcomes included mental wellbeing measures (mood states and subjective memory complaints (SMCs)) and quality of life (QoL). Furthermore, plasma apolipoprotein E4 (APOE4) was measured to determine whether APOE4 status influences responses to fish oil. Curcumin improved vigour (p = 0.044) compared to placebo and reduced SMCs compared to no curcumin treatment (p = 0.038). Fish oil did not affect any mood states, SMCs or QoL; however, responses to fish oil were affected by APOE4 status. In APOE4 non-carriers, fish oil increased vigour (p = 0.030) and reduced total mood disturbances (p = 0.048) compared to placebo. Improvements in mental wellbeing were correlated with increased QoL. Combining curcumin with fish oil did not result in additive effects. This exploratory analysis indicates that regular supplementation with either curcumin or fish oil (limited to APOE4 non-carriers) has the potential to improve some aspects of mental wellbeing in association with better QoL.

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Effect of 10 Days of Bed Rest on Skeletal Muscle in Healthy Older Adults

JAMA ◽

10.1001/jama.297.16.1772-b ◽

2007 ◽

Vol 297 (16) ◽

pp. 1769 ◽

Cited By ~ 404

Author(s):

Patrick Kortebein ◽

Arny Ferrando ◽

Juan Lombeida ◽

Robert Wolfe ◽

William J. Evans

Keyword(s):

Older Adults ◽

Skeletal Muscle ◽

Bed Rest ◽

Healthy Older Adults

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Short-term bed rest increases TLR4 and IL-6 expression in skeletal muscle of older adults

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00072.2013 ◽

2013 ◽

Vol 305 (3) ◽

pp. R216-R223 ◽

Cited By ~ 54

Author(s):

Micah J. Drummond ◽

Kyle L. Timmerman ◽

Melissa M. Markofski ◽

Dillon K. Walker ◽

Jared M. Dickinson ◽

...

Keyword(s):

Older Adults ◽

Skeletal Muscle ◽

Inflammatory Cytokines ◽

Muscle Biopsy ◽

Lean Mass ◽

Bed Rest ◽

Short Term ◽

Tlr4 Signaling ◽

Adult Skeletal Muscle ◽

Healthy Older Adults

Bed rest induces significant loss of leg lean mass in older adults. Systemic and tissue inflammation also accelerates skeletal muscle loss, but it is unknown whether inflammation is associated to inactivity-induced muscle atrophy in healthy older adults. We determined if short-term bed rest increases toll-like receptor 4 (TLR4) signaling and pro-inflammatory markers in older adult skeletal muscle biopsy samples. Six healthy, older adults underwent seven consecutive days of bed rest. Muscle biopsies (vastus lateralis) were taken after an overnight fast before and at the end of bed rest. Serum cytokine expression was measured before and during bed rest. TLR4 signaling and cytokine mRNAs associated with pro- and anti-inflammation and anabolism were measured in muscle biopsy samples using Western blot analysis and qPCR. Participants lost ∼4% leg lean mass with bed rest. We found that after bed rest, muscle levels of TLR4 protein expression and interleukin-6 (IL-6), nuclear factor-κB1, interleukin-10, and 15 mRNA expression were increased after bed rest ( P < 0.05). Additionally, the cytokines interferon-γ, and macrophage inflammatory protein-1β, were elevated in serum samples following bed rest ( P < 0.05). We conclude that short-term bed rest in older adults modestly increased some pro- and anti-inflammatory cytokines in muscle samples while systemic changes in pro-inflammatory cytokines were mostly absent. Upregulation of TLR4 protein content suggests that bed rest in older adults increases the capacity to mount an exaggerated, and perhaps unnecessary, inflammatory response in the presence of specific TLR4 ligands, e.g., during acute illness.

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