title: Effects of transdermal estrogen on collagen turnover at rest and in response to exercise in postmenopausal women.
abstract: Menopause is associated with loss of collagen content in the skin and tendon as well as accumulation of noncontractile tissue in skeletal muscle. The relative role of hormones and physical activity on these changes is not known. Accordingly, in a randomized, controlled, crossover study we investigated effects of transdermal estrogen replacement therapy (ERT) on type I collagen synthesis in tendon and skeletal muscle in 11 postmenopausal women. Patches with estrogen (Evorel) were placed on the skin above the patellar tendons and compared with no patch (control period). On day 2 all subjects performed one-legged exercise, and thereafter the exercised leg (EX leg) was compared with the nonexercised leg (Rest leg). Microdialysis catheters were placed in front of the patellar tendons and in the vastus lateralis muscle of both legs at days 3 and 5. The collected dialysate was analyzed for procollagen type I NH(2)-terminal propeptide (PINP), insulin-like growth factor I (IGF-I), and interleukin-6 (IL-6). Neither loading (Rest leg vs. EX leg) nor treatment (control vs. ERT) influenced peritendinous PINP, whereas combined exercise and ERT enhanced muscle PINP after 72 h (interaction between loading and treatment P = 0.008). In neither skeletal muscle nor peritendinous fluid were IGF-I and IL-6 influenced by treatment or exercise. In conclusion, ERT was associated with enhanced synthesis of type I collagen in the skeletal muscle in response to acute exercise. In perspective, this indicates that the availability of estrogen in postmenopausal women is important for repair of muscle damage or remodeling of the connective tissue within the skeletal muscle after exercise.
authors: Institute of Sports Medicine, Department of Orthopedic Surgery M81, Bispebjerg Hospital and Center for Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Bispebjerg Bakke 23,Copenhagen, Denmark.
authors: J
authors: J
authors: Pingel
authors: H
authors: H
authors: Langberg
authors: D
authors: D
authors: Skovgård
authors: S
authors: S
authors: Koskinen
authors: A
authors: A
authors: Flyvbjerg
authors: J
authors: J
authors: Frystyk
authors: M
authors: M
authors: Kjær
authors: M
authors: M
authors: Hansen
mesh_terms: D000368:Aged; D024042:Collagen Type I / Q000096:biosynthesis / Q000378:metabolism*; D018592:Cross-Over Studies; D004958:Estradiol / Q000097:blood / Q000378:metabolism; D015914:Estrogen Replacement Therapy / Q000379:methods; D004967:Estrogens / Q000008:administration & dosage*; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D017551:Microdialysis / Q000379:methods; D018482:Muscle, Skeletal / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D017847:Patellar Ligament / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D010446:Peptide Fragments / Q000378:metabolism; D017698:Postmenopause / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology*; D011347:Procollagen / Q000378:metabolism; D052097:Quadriceps Muscle / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D012146:Rest / Q000502:physiology*; D012867:Skin / Q000378:metabolism; D057968:Transdermal Patch
chemical_list: D024042:Collagen Type I; D004967:Estrogens; C508600:IL6 protein, human; D015850:Interleukin-6; D010446:Peptide Fragments; D011347:Procollagen; C047202:procollagen Type I N-terminal peptide; D004958:Estradiol; D007334:Insulin-Like Growth Factor I