Showing papers by "Stephen M. Roth published in 2004"
TL;DR: It is suggested that IL-15 is an important mediator of muscle mass response to resistance exercise training in humans and that genetic variation in IL15RA accounts for a significant proportion of the variability in this response.
Abstract: Interleukin-15 (IL-15) is an anabolic cytokine that is produced in skeletal muscle and directly affects muscle anabolism in animal and in vitro models. The contribution of IL-15 variability in musc...
215 citations
TL;DR: The VDR translation start site (FokI) polymorphism is significantly associated with FFM and sarcopenia in this cohort of older Caucasian men.
Abstract: We investigated the association of vitamin D receptor (VDR) genotype with fat-free mass (FFM) in a cohort of 302 older (aged 58-93 years) Caucasian men who underwent body composition analysis by dual-energy X-ray absorptiometry, and completed questionnaires addressing comorbidities, physical activity, and dietary intake. All participants were genotyped for a VDR translation start site (FokI) polymorphism [FF (37.7%), Ff (48.4%), and ff (13.9%)] and the previously studied BsmI polymorphism [BB (24.9%), Bb (37.7%), and bb (37.4%)]. The BsmI polymorphism was not associated with FFM in any analysis; however, the FokI polymorphism was significantly associated with total FFM, appendicular FFM, and relative (kg/m(2)) appendicular FFM (all p <.05), with the FF group demonstrating significantly lower FFM than the Ff and ff groups (e.g., total FFM: FF = 57.6 +/- 0.4, Ff = 59.4 +/- 0.4, ff = 59.4 +/- 0.7 kg; p <.02). Age-adjusted logistic regression revealed a 2.17-fold higher risk for sarcopenia (defined previously as appendicular FFM <7.26 kg/m(2)) in FF homozygotes (95% CI [confidence interval] = 1.19-3.85; p =.03) compared to men with one or more f alleles. The VDR translation start site (FokI) polymorphism is significantly associated with FFM and sarcopenia in this cohort of older Caucasian men.
146 citations
TL;DR: The identification of an antimyostatin monoclonal antibody shows the promise of myostatin as a target for muscle-wasting disorders; the antibody has already been shown to increase muscle mass in healthy older mice and muscle function in postnatal mdx mice.
Abstract: Purpose of reviewThis review discusses recent developments in myostatin research, focusing on the basic actions of myostatin on skeletal muscle, the identification of key regulatory elements of the myostatin pathway, and the promise of myostatin as a therapeutic target in muscle-related disorders.Re
70 citations
TL;DR: The hypothesis that variation within a gene known to influence developing muscle affects muscle mass and muscle function in later life is supported.
Abstract: The influence of insulin-like growth factor-2 (IGF2) genotype on total body fat-free mass (FFM), muscle strength, and sustained power (SP) was evaluated repeatedly at ∼2-yr intervals in two cohorts...
60 citations
TL;DR: The results do not support an effect of the CNTF null allele on body composition, contrary to previous findings.
Abstract: Exogenous ciliary neurotrophic factor (CNTF) administration causes significant weight loss in both humans and animal models, but the effects of endogenous CNTF and the CNTF null allele on body composition are not fully understood. A recent study in a European cohort demonstrated a significantly higher body weight and body mass index (BMI) in older males homozygous for the CNTF null allele (A/A genotype). We sought to replicate these findings in three cohorts: the Baltimore Longitudinal Study on Aging (BLSA) consisting of 422 adult men and women (19-90 years); the Study of Osteoporotic Risk in Men (STORM) consisting of 333 older men (50-84 years); and a third sample obtained by combining older males aged 59-73 years from the BLSA and STORM cohorts (n=286). In contrast to the European study, we were unable to detect a significant association between CNTF genotype and body weight in the BLSA (P=0.49), the STORM (P=0.28), or the combined samples (P=0.72). There was also no significant association observed between CNTF genotype and BMI in the BLSA (P=0.59), the STORM (P=0.34) or the combined (P=0.56) samples. In addition, we were unable to detect a significant association between CNTF genotype and total body fat (P=0.95) or fat-free mass (P=0.86) in the BLSA cohort. Our results do not support an effect of the CNTF null allele on body composition, contrary to previous findings.
11 citations