Effects of estrogen replacement and lower androgen status on skeletal muscle collagen and myofibrillar protein synthesis in postmenopausal women

TY - JOUR

T1 - Effects of estrogen replacement and lower androgen status on skeletal muscle collagen and myofibrillar protein synthesis in postmenopausal women

AU - Hansen, Mette Damborg

AU - Skovgaard, Dorthe

AU - Reitelseder, Søren

AU - Holm, Lars

AU - Langbjerg, Henning

AU - Kjaer, Michael

PY - 2012/10

Y1 - 2012/10

N2 - Our aim was to determine synthesis rate of myofibrillar and collagen proteins in 20 postmenopausal women, who were either nonusers (Controls) or users of estrogen replacement therapy (ERT) after hysterectomy/oophorectomy. Myofibrillar and muscle collagen protein fractional synthesis rate (FSR) were determined in a nonexercised leg and 24 hours after exercise in the contralateral leg. A significant interaction between treatment and mechanical loading was observed in myofibrillar protein FSR. At rest, myofibrillar protein FSR was found to be lower in ERT users than in Controls. Exercise enhanced myofibrillar protein FSR only in ERT users. Similarly, muscle collagen FSR tended to be lower in ERT users compared with Controls. In ERT participants, the androgen profile was reduced, whereas estradiol and sex hormone-binding globulin were higher. In conclusion, at rest, myofibrillar protein FSR was lower in hysterectomized/oophorectomized women using ERT compared with healthy postmenopausal women. Nevertheless, resistance exercise in combination with ERT seems to have a counteracting effect on myofibrillar FSR in hysterectomized/oophorectomized women.

AB - Our aim was to determine synthesis rate of myofibrillar and collagen proteins in 20 postmenopausal women, who were either nonusers (Controls) or users of estrogen replacement therapy (ERT) after hysterectomy/oophorectomy. Myofibrillar and muscle collagen protein fractional synthesis rate (FSR) were determined in a nonexercised leg and 24 hours after exercise in the contralateral leg. A significant interaction between treatment and mechanical loading was observed in myofibrillar protein FSR. At rest, myofibrillar protein FSR was found to be lower in ERT users than in Controls. Exercise enhanced myofibrillar protein FSR only in ERT users. Similarly, muscle collagen FSR tended to be lower in ERT users compared with Controls. In ERT participants, the androgen profile was reduced, whereas estradiol and sex hormone-binding globulin were higher. In conclusion, at rest, myofibrillar protein FSR was lower in hysterectomized/oophorectomized women using ERT compared with healthy postmenopausal women. Nevertheless, resistance exercise in combination with ERT seems to have a counteracting effect on myofibrillar FSR in hysterectomized/oophorectomized women.

KW - Aged

KW - Androgens

KW - Case-Control Studies

KW - Collagen

KW - Cross-Sectional Studies

KW - Estradiol

KW - Estrogen Replacement Therapy

KW - Exercise

KW - Female

KW - Humans

KW - Hysterectomy

KW - Middle Aged

KW - Muscle Proteins

KW - Muscle, Skeletal

KW - Ovariectomy

KW - Postmenopause

KW - Sex Hormone-Binding Globulin

U2 - 10.1093/gerona/gls007

DO - 10.1093/gerona/gls007

M3 - Journal article

C2 - 22389460

SN - 1079-5006

VL - 67

SP - 1005

EP - 1013

JO - Journals of Gerontology. Series A: Biological Sciences & Medical Sciences

JF - Journals of Gerontology. Series A: Biological Sciences & Medical Sciences

IS - 10

ER -