PHYSICAL EXERCISE AND FITNESS :
VITAMINS: VITAMIN D :
High Levels of Vitamin D May Improve Muscle Strength
High Levels of Vitamin D May Improve Muscle Strength
Written by Ana Sandoiu
Published: Thursday 16 February 2017
Medical News Today (MNT)
“Vitamin D has numerous health benefits, from keeping our bones and teeth healthy to potentially even protecting against diseases such as diabetes and certain types of cancer. A new study suggests that vitamin D may also improve muscle strength. [vitamin D written in the sand] New research suggests that active levels of vitamin D may improve muscle function. Vitamin D is key for the development and maintenance of healthy bones. It also has many positive effects on the immune system, endocrine glands, and cardiovascular system.”
Some observational studies have linked vitamin D deficiency with a higher risk of colorectal and breast cancer, while others have found a correlation between vitamin D levels and the risk of autoimmune diseases such as type 1 diabetes and multiple sclerosis.
A new study – carried out by researchers from the University of Birmingham in the United Kingdom – investigates the effect of vitamin D levels on muscle strength.
The findings were published in the journal PLOS One.
Analyzing the effect of vitamin D on muscle mass
Using innovative technology, researchers were able to study both active and inactive vitamin D levels, together with their impact on muscle strength.
Vitamin D – whether it is in D2 or D3 form – is, by itself, biologically inactive, until it is activated by two enzymatic reactions: one in the liver and the other in the kidney.
Dr. Zaki Hassan-Smith, from the University of Birmingham, explains the novelty of the research procedure in the current study:
“Previous studies have tested for the inactive forms of vitamin D in the bloodstream, to measure vitamin D deficiency. Here, we were able to develop a new method of assessing multiple forms of vitamin D, alongside extensive testing of body composition, muscle function, and muscle gene expression.”
The team examined vitamin D levels in 116 healthy participants aged between 20 and 74. They also measured the participants’ body fat and “lean body mass” – a measure of muscle mass, obtained by subtracting the body fat weight from the total body weight.
Supplemental vitamin D may enhance muscle function
Conversely, women with more body fat tended to have less inactive vitamin D. While this does suggest a relationship between vitamin D and body composition, the active form of vitamin D did not correlate with body fat. Instead, vitamin D levels were linked with lean mass.
25-hydroxyvitamin D3 and 1,25-dihydroxyvitamin D3 exert distinct effects on human skeletal muscle function and gene expression
Zaki K. Hassan-Smith, Carl Jenkinson, David J. Smith, Ivan Hernandez, Stuart A. Morgan, Nicola J. Crabtree, Neil J. Gittoes, Brian G. Keevil, Paul M. Stewart, Martin Hewison
Published: February 15, 2017
Age-associated decline in muscle function represents a significant public health burden. Vitamin D-deficiency is also prevalent in aging subjects, and has been linked to loss of muscle mass and strength (sarcopenia), but the precise role of specific vitamin D metabolites in determining muscle phenotype and function is still unclear. To address this we quantified serum concentrations of multiple vitamin D metabolites, and assessed the impact of these metabolites on body composition/muscle function parameters, and muscle biopsy gene expression in a retrospective study of a cohort of healthy volunteers. Active serum 1,25-dihydroxyvitamin D3 (1a,25(OH)2D3), but not inactive 25-hydroxyvitamin D3 (25OHD3), correlated positively with measures of lower limb strength including power (rho = 0.42, p = 0.02), velocity (Vmax, rho = 0.40, p = 0.02) and jump height (rho = 0.36, p = 0.04). Lean mass correlated positively with 1a,25(OH)2D3 (rho = 0.47, p = 0.02), in women. Serum 25OHD3 and inactive 24,25-dihydroxyvitamin D3 (24,25(OH)2D3) had an inverse relationship with body fat (rho = -0.30, p = 0.02 and rho = -0.33, p = 0.01, respectively). Serum 25OHD3 and 24,25(OH)2D3 were also correlated with urinary steroid metabolites, suggesting a link with glucocorticoid metabolism. PCR array analysis of 92 muscle genes identified vitamin D receptor (VDR) mRNA in all muscle biopsies, with this expression being negatively correlated with serum 25OHD3, and Vmax, and positively correlated with fat mass. Of the other 91 muscle genes analysed by PCR array, 24 were positively correlated with 25OHD3, but only 4 were correlated with active 1a,25(OH)2D3. These data show that although 25OHD3 has potent actions on muscle gene expression, the circulating concentrations of this metabolite are more closely linked to body fat mass, suggesting that 25OHD3 can influence muscle function via indirect effects on adipose tissue. By contrast, serum 1a,25(OH)2D3 has limited effects on muscle gene expression, but is associated with increased muscle strength and lean mass in women. These pleiotropic effects of the vitamin D metabolome on muscle function indicate that future supplementation studies should not be restricted to conventional analysis of the major circulating form of vitamin D, 25OHD3.
Citation: Hassan-Smith ZK, Jenkinson C, Smith DJ, Hernandez I, Morgan SA, Crabtree NJ, et al. (2017) 25-hydroxyvitamin D3 and 1,25-dihydroxyvitamin D3 exert distinct effects on human skeletal muscle function and gene expression. PLoS ONE 12(2): e0170665. doi:10.1371/journal.pone.0170665
The effects of vitamin D on calcium homeostasis and bone health are well established. In recent years there has been great interest in its non-skeletal actions, with growing evidence from epidemiological, basic and clinical studies that vitamin D status is associated with effects including those on muscle function, body fat, immunity and cardiovascular disease risk . Myopathy has long-been recognised to co-exist with reduced bone mineralization in the severe vitamin D deficiency states of rickets and osteomalacia . In view of the great public health burden of so-called sarcopenia and age-associated declines in muscle strength and function, there is significant interest in whether vitamin D may have a role in improving the healthy lifespan. Recent meta-analyses indicate that vitamin D supplementation in deficient elderly individuals reduces risk of falls . There is also some evidence of beneficial effects on muscle strength and physical performance, however this is limited by heterogeneity of study designs, so that current guidelines do not recommend vitamin D supplementation for this indication .
Although basic research using cell culture and animal models has identified pathways by which vitamin D impacts upon muscle function, the situation in humans requires further delineation. In particular, although biopsy studies have demonstrated changes in muscle morphology in vitamin D deficient disease states, detailed analyses of the relationship between vitamin D status and gene expression of muscle atrophy markers are lacking . There is also debate as to the optimal circulating levels of vitamin D, with further data on the impacts on human health and function required . Furthermore in clinical practice, vitamin D status is defined by measurement of a single metabolite, 25-hydroxyvitamin D3 (25OHD3). Recently developed high-throughput liquid chromatography-tandem mass spectrometry (LC-MS/MS) techniques allow the quantification of multiple vitamin D metabolites, and to date this approach has not been used to assess their relationship with markers of muscle mass and function . With these observations in mind, the aim of the current study was to perform an in-depth analysis of the relationship between serum vitamin D metabolites and muscle phenotype in a healthy human cohort.
Sections of This Article
Materials and methods
Serum high-throughput vitamin D metabolite analysis by liquid chromatography tandem-mass spectrometry
Urine steroid profiling by gas chromatography/mass spectrometry
Dual-energy x-ray absorptiometry scan
Muscle strength testing
Vastus lateralis muscle biopsy
Quantitative (real-time) PCR array analyses
Materials and methods
Reader Comments (1)
Media Coverage (0)
Vitamin D metabolites and body composition and biochemical parameters
Vitamin D metabolites and muscle function parameters
25OHD3, 1,25(OH)2D3, VDR and skeletal muscle gene expression
The work was supported by an NIH P50 grant to M.H. (AR063020-01 NIH/NIAMS) and the European Research Council (Advanced Grant Precort to P.M.S.). The authors thank Peter Nightingale, Theresa Brady, Pamela Jones, Claire Brown (National Institute for Health Research-Wellcome Trust Clinical Research Facility, Birmingham), Dean P. Larner, Angela E. Taylor and Beverly Hughes (University of Birmingham). The clinical visit was carried out at the National Institute for Health Research (NIHR)/Wellcome Trust Birmingham Clinical Research Facility. The views expressed are those of the authors(s) and not necessarily those of the NHS, the NIHR or the Department of Health.
Conceptualization: ZKH-S CJ SAM PMS MH.
Data curation: ZKH-S NJC NLG.
Formal analysis: ZKH-S MH.
Funding acquisition: PMS MH.
Investigation: SAM IH NJC BGK.
Methodology: ZKH-S CJ PMS MH.
Project administration: ZKH-S PMS MH.
Resources: BGK NLG.
Software: ZKH-S DJS.
Supervision: BGK PMS MH.
Validation: ZKH-S CJ NJC MH.
Writing original draft: ZKH-S MH.
Writing review & editing: DJS NJG PMS.
Temple University and Google Sites Research Guides
AND Discussion Group Directory
RESEARCH PAPER WRITING
DISABILITIES AND EMPLOYMENT
PUBLIC HEALTH RESOURCES INCLUDING EBOLA
STATISTICS SOURCES RESEARCH GUIDE
Social Work and Social Issues Discussion Group
Tourism Discussion Group
Digital Scholarship Discussion Group
Copyright Research Guide
Copyright, Intellectual Property and Plagiarism Sources
Articles by David Dillard
Information Literacy (Russell Conwell Guide)
Temple University Site Map
Bushell, R. & Sheldon, P. (eds),
Wellness and Tourism: Mind, Body, Spirit,
Place, New York: Cognizant Communication Books.
Wellness Tourism: Bibliographic and Webliographic Essay
David P. Dillard
Improve Your Chances for Indoor Gardening Success
HEALTH DIET FITNESS RECREATION SPORTS TOURISM
Please Ignore All Links to JIGLU
in search results for Net-Gold and related lists.
The Net-Gold relationship with JIGLU has
been terminated by JIGLU and these are dead links.
Temple University Listserv Alert :
Years 2009 and 2010 Eliminated from Archives
You receive all messages sent to this group.
View/Reply Online (#716):
View All Messages In Topic (1):