title: The Effects of Muscle Mass on Homocyst(e)ine Levels in Plasma and Urine.
abstract: The present study was designed to examine the relationship between homocyst(e)ine (H[e]) levels and muscle mass. Two experimental groups each of 24 Caucasian males, one consisting of higher-muscle mass subjects (HMM) and the other of lower-muscle mass subjects (LMM) participated in this study. Muscle mass was estimated from 24-hour urine collections of creatinine (Crt). Muscle mass was 40.3 ± 15.9 kg in HMM and 37.2 ± 11.4 kg in LMM (P= 0.002). Mean plasma H(e) levels in HMM were 10.29 ± 2.9 nmol/mL, and in LMM were 10.02 ± 2.4 nmol/L (Not significant, [NS]). Urinary H(e) levels (UH[e]) were 9.95 ± 4.3 nmol/mL and 9.22 ± 2.9 nmol/mL for HMM and LMM, respectively (NS). Plasma H(e) levels correlated well with UH(e) (HMM: r= 0.58, P= 0.009; LMM: r= 0.66, P= 0.004). Muscle mass and was not correlated to either plasma H(e) or UH(e). However, in HMM trends were identified for body mass to be correlated with UH(e) (r= 0.39, P= 0.10) and UCrt (r= 0.41, P= 0.08). Surprisingly, in HMM plasma and UCrt were only weakly correlated (r= 0.44, P= 0.06). Our results do not support a causal relationship between the amount of muscle mass and H(e) levels in plasma or urine.
authors.affiliation: Division of Pathobiology and Immunology, Oregon Regional Primate Research Center, Beaverton, OR, USA.
authors.forename: M René
authors.initials: MR
authors.lastname: Malinow
authors.affiliation: Physiology of Exercise Unit, School of Physical Education, Sport & Leisure, De Montfort University, Bedford, UK; The Wright Foundation, Dundee, UK.
authors.forename: Craig L
authors.initials: CL
authors.lastname: Lister
authors.affiliation: Physiology of Exercise Unit, School of Physical Education, Sport & Leisure, De Montfort University, Bedford, UK; The Wright Foundation, Dundee, UK.
authors.forename: Carl
authors.initials: C
authors.lastname: DE Crée
keywords: Creatinine; estrogen; gender-differences; homocysteine; skeletal muscle