TY - JOUR
T1 - Estradiol effects on the growth hormone/insulin-like growth factor-1 axis in amenorrheic athletes
AU - Waters, Debra L.
AU - Dorin, Richard I.
AU - Qualls, Clifford R.
AU - Ruby, Brent C.
AU - Baumgartner, Richard N.
AU - Robergs, Robert A.
PY - 2003/2
Y1 - 2003/2
N2 - Disruption of the growth hormone/insulin-like growth factor-1 (GH/IGF-1) axis has been reported and studied in menopause, hypothalamic amenorrhea, and anorexia nervosa, but not in weight-stable amenorrheic athletes. We investigated the effects of short-term transdermal estradiol on basal and exercise-stimulated serum GH, IGF-1, and associated binding proteins (IGFBP-1 and IGFBP-3) in seven weight-stable female amenorrheic athletes with percentage body fats greater that 12%. Each subject received a 72h placebo patch followed by 144h of transdermal estradiol. Serum samples for GH, IGF-1, IGFBP-1, and IGFBP-3 were obtained at baseline (t1), 72hr (t2), 144hr (t3), and during three 90-minute trials of aerobic exercise. Basal, and exercise GH, 1GF-1, and IGFBP-1 were not different between trials. Baseline IGFBP-3 decreased from t1 to t2 (p = 0.04) and serum free fatty acids increased from t1 to t2, and t1 to t3 (p = 0.04, and 0.02 respectively). These findings differ from postmenopausal women, and women having weightloss-associated amenorrhea, suggesting that estrogen, exercise, and nutritional deficiencies may have independent effects on the GH/IGF-1 axis.
AB - Disruption of the growth hormone/insulin-like growth factor-1 (GH/IGF-1) axis has been reported and studied in menopause, hypothalamic amenorrhea, and anorexia nervosa, but not in weight-stable amenorrheic athletes. We investigated the effects of short-term transdermal estradiol on basal and exercise-stimulated serum GH, IGF-1, and associated binding proteins (IGFBP-1 and IGFBP-3) in seven weight-stable female amenorrheic athletes with percentage body fats greater that 12%. Each subject received a 72h placebo patch followed by 144h of transdermal estradiol. Serum samples for GH, IGF-1, IGFBP-1, and IGFBP-3 were obtained at baseline (t1), 72hr (t2), 144hr (t3), and during three 90-minute trials of aerobic exercise. Basal, and exercise GH, 1GF-1, and IGFBP-1 were not different between trials. Baseline IGFBP-3 decreased from t1 to t2 (p = 0.04) and serum free fatty acids increased from t1 to t2, and t1 to t3 (p = 0.04, and 0.02 respectively). These findings differ from postmenopausal women, and women having weightloss-associated amenorrhea, suggesting that estrogen, exercise, and nutritional deficiencies may have independent effects on the GH/IGF-1 axis.
KW - Free fatty acids
KW - Insulin-like growth factor binding protein-1
KW - Insulin-like growth factor binding protein-3
KW - Transdermal estradiol
UR - http://www.scopus.com/inward/record.url?scp=0038621656&partnerID=8YFLogxK
U2 - 10.1139/h03-006
DO - 10.1139/h03-006
M3 - Article
C2 - 12671196
AN - SCOPUS:0038621656
SN - 1066-7814
VL - 28
SP - 64
EP - 78
JO - Canadian Journal of Applied Physiology
JF - Canadian Journal of Applied Physiology
IS - 1
ER -