This Article Full Text Full Text (PDF) All Versions of this Article: 27/4/560    most recent Author Manuscript (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Winters, S. J. Articles by Brufsky, A. Search for Related Content PubMed PubMed Citation Articles by Winters, S. J. Articles by Brufsky, A.

Journal of Andrology, Vol. 27, No. 4, July/August 2006
Copyright © American Society of Andrology

Inhibin-B Levels in Healthy Young Adult Men and Prepubertal Boys: Is Obesity the Cause for the Contemporary Decline in Sperm Count Because of Fewer Sertoli Cells?

STEPHEN J. WINTERS^*,

VENUS HADEED

MARY ANN DYKY

ADAM BRUFSKY

From the ^* Department of Medicine, University of Louisville, Louisville, Kentucky; and the Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania.

Correspondence to: Dr Stephen J Winters, Division of Endocrinology, Metabolism and Diabetes, University of Louisville, ACB-A3G11, 550 Jackson St, Louisville, KY, 40202 (e-mail: sjwint01{at}louisville.edu).

Inhibin-B is a heterodimeric glycoprotein produced by Sertoli cells. Although inhibin-B levels are low when seminiferous tubules are damaged, studies in normal monkeys reveal that inhibin-B levels also correlate positively with Sertoli cell number. In this study, we measured inhibin-B levels in healthy young adult men aged 18–24 years and in prepubertal boys aged 5–9 years in relation to body mass index (BMI). Inhibin-B levels declined with increasing obesity in young adult men; values were 26% lower in men who were obese compared to normal-weight men. Sex hormone–binding globulin and total testosterone, but not free testosterone, were also lower with increasing BMI; serum follicle-stimulating hormone and luteinizing hormone levels were unaffected by obesity. In prepubertal boys, by contrast, inhibin-B was unaffected by obesity. We propose that reduced levels of inhibin-B indicate that obese men have fewer Sertoli cells than men of normal weight. Moreover, normal values in obese prepubertal boys suggest that the effect of obesity on inhibin-B is established during puberty. Finally, because each Sertoli cell is thought to support a finite number of germ cells, fewer Sertoli cells in obesity may predispose to a lower sperm count in adulthood. We speculate that the escalating prevalence of obesity and insulin resistance among adolescents might negatively influence male reproductive function for the next generation.

     Key words: Male infertility, testis, puberty

This article has been cited by other articles:

				T.M. Stewart, D.Y. Liu, C. Garrett, N. Jorgensen, E.H. Brown, and H.W.G. Baker Associations between andrological measures, hormones and semen quality in fertile Australian men: inverse relationship between obesity and sperm output Hum. Reprod., July 1, 2009; 24(7): 1561 - 1568. [Abstract] [Full Text] [PDF]

				K Faisal, V S Periasamy, S Sahabudeen, A Radha, R Anandhi, and M A Akbarsha Spermatotoxic effect of aflatoxin B1 in rat: extrusion of outer dense fibres and associated axonemal microtubule doublets of sperm flagellum Reproduction, March 1, 2008; 135(3): 303 - 310. [Abstract] [Full Text] [PDF]