| Autor: |
O'Leary MF; Sport and Health Sciences, College of Life and Environmental Sciences, Exeter University, Exeter EX1 2LU, UK., Jackman SR; Sport and Health Sciences, College of Life and Environmental Sciences, Exeter University, Exeter EX1 2LU, UK., Sabou VR; Sport and Health Sciences, College of Life and Environmental Sciences, Exeter University, Exeter EX1 2LU, UK., Campbell MI; Sport and Health Sciences, College of Life and Environmental Sciences, Exeter University, Exeter EX1 2LU, UK., Tang JCY; Norwich Medical School, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK., Dutton J; Norwich Medical School, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK., Bowtell JL; Sport and Health Sciences, College of Life and Environmental Sciences, Exeter University, Exeter EX1 2LU, UK. |
| Abstrakt: |
Shatavari has long been used as an Ayurvedic herb for women's health, but empirical evidence for its effectiveness has been lacking. Shatavari contains phytoestrogenic compounds that bind to the estradiol receptor. Postmenopausal estradiol deficiency contributes to sarcopenia and osteoporosis. In a randomised double-blind trial, 20 postmenopausal women (68.5 ± 6 years) ingested either placebo ( N = 10) or shatavari ( N = 10; 1000 mg/d, equivalent to 26,500 mg/d fresh weight shatavari) for 6 weeks. Handgrip and knee extensor strength were measured at baseline and at 6 weeks. Vastus lateralis (VL) biopsy samples were obtained. Data are presented as difference scores (Week 6-baseline, median ± interquartile range). Handgrip (but not knee extensor) strength was improved by shatavari supplementation (shatavari +0.7 ± 1.1 kg, placebo -0.4 ± 1.3 kg; p = 0.04). Myosin regulatory light chain phosphorylation, a known marker of improved myosin contractile function, was increased in VL following shatavari supplementation (immunoblotting; placebo -0.08 ± 0.5 a.u., shatavari +0.3 ± 1 arbitrary units (a.u.); p = 0.03). Shatavari increased the phosphorylation of Akt ser473 (Akt ser473 (placebo -0.6 ± 0.6 a.u., shatavari +0.2 ± 1.3 a.u.; p = 0.03) in VL. Shatavari supplementation did not alter plasma markers of bone turnover (P1NP, β-CTX) and stimulation of human osteoblasts with pooled sera ( N = 8 per condition) from placebo and shatavari supplementation conditions did not alter cytokine or metabolic markers of osteoblast activity. Shatavari may improve muscle function and contractility via myosin conformational change and further investigation of its utility in conserving and enhancing musculoskeletal function, in larger and more diverse cohorts, is warranted. |
