Hormone therapy attenuates exercise-induced skeletal muscle damage in postmenopausal women.
Hormone therapy (HT) is a potential treatment to relieve symptoms of menopause and prevent the onset of disease such as osteoporosis in postmenopausal women. We evaluated changes in markers of exercise-induced skeletal muscle damage and inflammation [serum creatine kinase (CK), serum lactate dehydrogenase (LDH), and skeletal muscle mRNA expression of IL-6, IL-8, IL-15, and TNF-alpha] in postmenopausal women after a high-intensity resistance exercise bout. Fourteen postmenopausal women were divided into two groups: women not using HT (control; n = 6, 59 +/- 4 yr, 63 +/- 17 kg) and women using traditional HT (HT; n = 8, 59 +/- 4 yr, 89 +/- 24 kg). Both groups performed 10 sets of 10 maximal eccentric repetitions of single-leg extension on the Cybex dynamometer at 60 degrees /s with 20-s rest periods between sets. Muscle biopsies of the vastus lateralis were obtained from the exercised leg at baseline and 4 h after the exercise bout. Gene expression was determined by RT-PCR for IL-6, IL-8, IL-15, and TNF-alpha. Blood draws were performed at baseline and 3 days after exercise to measure CK and LDH. Independent t-tests were performed to test group differences (control vs. HT). A probability level of P <or= 0.05 was used to determine statistical significance. We observed significantly greater changes in mRNA expression of IL-6, IL-8, IL-15, and TNF-alpha (P <or= 0.01) in the control group compared with the HT group after the exercise bout. CK and LDH levels were significantly greater after exercise (P <or= 0.01) in the control group. Postmenopausal women not using HT experienced greater muscle damage after maximal eccentric exercise, indicating a possible protective effect of HT against exercise-induced skeletal muscle damage.
Dieli-Conwright
Christina M
CM
Division of Biokinesiology and Physical Therapy, Clinical Exercise Research Center, USC/Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, California, USA.
Spektor
Tanya M
TM
Rice
Judd C
JC
Sattler
F R
FR
Schroeder
E Todd
ET
D000368:Aged; D000886:Anthropometry; D001774:Blood Chemical Analysis; D001823:Body Composition / Q000502:physiology; D003402:Creatine Kinase / Q000097:blood; D016207:Cytokines / Q000096:biosynthesis; D018076:DNA, Complementary / Q000096:biosynthesis / Q000235:genetics; D004032:Diet; D015914:Estrogen Replacement Therapy; D015444:Exercise / Q000502:physiology*; D005260:Female; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000097:blood; D006801:Humans; D007249:Inflammation / Q000473:pathology; D007770:L-Lactate Dehydrogenase / Q000097:blood; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology; D053580:Muscle Strength / Q000502:physiology; D018482:Muscle, Skeletal / Q000473:pathology* / Q000502:physiology*; D010809:Physical Fitness / Q000502:physiology; D017698:Postmenopause / Q000502:physiology*; D012313:RNA / Q000096:biosynthesis; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis / Q000097:blood
D016207:Cytokines; D018076:DNA, Complementary; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D012313:RNA; D007770:L-Lactate Dehydrogenase; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D003402:Creatine Kinase