Influence of age and sex on serum concentrations of total dimeric activin A

Department of Internal Medicine, Universita di Modena, Italy.

Several studies have shown that activin A is secreted in substantial amounts into the systemic circulation. The changes that occur during menstrual cycle and pregnancy suggest a correlation with reproductive function. At present, however, no definitive evidence has confirmed this pattern throughout adult life; moreover, neither the origin nor the physiological implications of this circulating growth factor have been clearly defined. The aim of the present study was to evaluate whether circulating concentrations of activin A change in adult men and women according to age and sex, and to examine the possible correlation with serum concentrations of FSH. Total dimeric activin A was measured using a specific two-site enzyme immunoassay in serum specimens collected from a cohort of normal individuals enrolled in an epidemiological survey. A group of men (n = 106) and one of women (n=151) were subdivided into six age groups (20-30, 30-40, 40-50, 50-60, 60-70 and 70-90 years). In a small group of 8 men and 11 women, serum concentrations of activin A were evaluated twice, in specimens collected at an interval of 10 years. Serum FSH concentrations were also measured in all specimens. Serum concentrations of activin A were not significantly different in men and women and showed an age-related progressive increase between 20 and 50 years of age (P<0.01, those aged 40-50 compared with those aged 20-30 years). After the age of 50 years, activin A concentrations remained in the same range of values in women, whereas they increased significantly in men, reaching peak values between 70 and 90 years (P<0.01 compared with the group aged between 20 and 50 years). From the age of 50 years, activin A concentrations were significantly greater in men compared with those in women in the corresponding age groups (P<0.001). Activin A concentrations correlated with age in men, but not in women. No significant correlation between concentrations of activin A and FSH was found in either sex. Activin A concentrations in specimens collected 10 years apart showed an increase in seven of eight men, but not in women. Finally, no significant variations of activin A concentrations were observed when fertile and postmenopausal women were compared. The present data indicate that circulating concentrations of activin A vary according to age; furthermore, men older than 50 years have greater concentrations than women. These changes, which occur irrespectively of FSH concentrations, indicate that circulating activin A is not a hormone of the reproductive axis.

This article has been cited by other articles:

				D. D. Elsholz, V. Padmanabhan, R. L. Rosenfield, P. R. Olton, D. J. Phillips, and C. M. Foster GnRH agonist stimulation of the pituitary-gonadal axis in children: age and sex differences in circulating inhibin-B and activin-A Hum. Reprod., December 1, 2004; 19(12): 2748 - 2758. [Abstract] [Full Text] [PDF]

				C. M. Foster, P. R. Olton, M. S. Racine, D. J. Phillips, and V. Padmanabhan Sex differences in FSH-regulatory peptides in pubertal age boys and girls and effects of sex steroid treatment Hum. Reprod., July 1, 2004; 19(7): 1668 - 1676. [Abstract] [Full Text] [PDF]

				N. A. Klein, B. S. Houmard, K. R. Hansen, T. K. Woodruff, P. M. Sluss, W. J. Bremner, and M. R. Soules Age-Related Analysis of Inhibin A, Inhibin B, and Activin A Relative to the Intercycle Monotropic Follicle-Stimulating Hormone Rise in Normal Ovulatory Women J. Clin. Endocrinol. Metab., June 1, 2004; 89(6): 2977 - 2981. [Abstract] [Full Text] [PDF]

				L. Cobellis, F. M. Reis, S. Luisi, S. Danero, L. Pirtoli, G. Scambia, and F. Petraglia High Concentrations of Activin A in the Peritoneal Fluid of Women With Epithelial Ovarian Cancer Reproductive Sciences, May 1, 2004; 11(4): 203 - 206. [Abstract] [PDF]

				C. Welt, Y. Sidis, H. Keutmann, and A. Schneyer Activins, Inhibins, and Follistatins: From Endocrinology to Signaling. A Paradigm for the New Millennium Experimental Biology and Medicine, October 1, 2002; 227(9): 724 - 752. [Abstract] [Full Text] [PDF]

				F. M. Reis, L. Cobellis, L. C. Tameirao, G. Anania, S. Luisi, I. S. B. Silva, W. Gioffre, A. M. di Blasio, and F. Petraglia Serum and Tissue Expression of Activin A in Postmenopausal Women with Breast Cancer J. Clin. Endocrinol. Metab., May 1, 2002; 87(5): 2277 - 2282. [Abstract] [Full Text] [PDF]

				R. J. Norman, C. R. Milner, N. P. Groome, and D. M. Robertson Circulating follistatin concentrations are higher and activin concentrations are lower in polycystic ovarian syndrome Hum. Reprod., April 1, 2001; 16(4): 668 - 672. [Abstract] [Full Text] [PDF]

				B.-D. Chang, K. Watanabe, E. V. Broude, J. Fang, J. C. Poole, T. V. Kalinichenko, and I. B. Roninson Effects of p21Waf1/Cip1/Sdi1 on cellular gene expression: Implications for carcinogenesis, senescence, and age-related diseases PNAS, April 11, 2000; 97(8): 4291 - 4296. [Abstract] [Full Text] [PDF]

				C. K. Welt, D. J. McNicholl, A. E. Taylor, and J. E. Hall Female Reproductive Aging Is Marked by Decreased Secretion of Dimeric Inhibin J. Clin. Endocrinol. Metab., January 1, 1999; 84(1): 105 - 111. [Abstract] [Full Text]