Potential detrimental effects of a phytoestrogen-rich diet on male fertility in mice.
Soy and soy-based products are widely consumed by infants and adult individuals. There has been speculation that the presence of isoflavone phytoestrogens in soybean cause adverse effects on the development and function of the male reproductive system. The purpose of this study was to examine the influence of dietary soy and phytoestrogens on testicular and reproductive functions. Male mice were fed from conception to adulthood with either a high soy-containing diet or a soy-free diet. Although adult mice fed a soy-rich diet exhibited normal male behaviour and were fertile, we observed a reduced proportion of haploid germ cells in testes correlating with a 25% decrease in epididymal sperm counts and a 21% reduction in litter size. LH and androgens levels were not affected but transcripts coding for androgen-response genes in Sertoli cells and Gapd-s, a germ cell-specific gene involved in sperm glycolysis and mobility were significantly reduced. In addition, we found that dietary soy decreased the size of the seminal vesicle but without affecting its proteolytic activity. Taken together, these studies show that long-term exposure to dietary soy and phytoestrogens may affect male reproductive function resulting in a small decrease in sperm count and fertility.
Cederroth
Christopher R
CR
Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva, Switzerland.
Zimmermann
Celine
C
Beny
Jean-Louis
JL
Schaad
Olivier
O
Combepine
Chantal
C
Descombes
Patrick
P
Doerge
Daniel R
DR
Pralong
François P
FP
Vassalli
Jean-Dominique
JD
Nef
Serge
S
D000818:Animals; D015153:Blotting, Western; D004032:Diet; D005298:Fertility / Q000502:physiology*; D005434:Flow Cytometry; D006728:Hormones / Q000097:blood; D007529:Isoflavones / Q000097:blood; D008297:Male; D051379:Mice; D046228:Microarray Analysis; D048789:Phytoestrogens / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013025:Glycine max / Q000378:metabolism*; D013076:Sperm Count
D006728:Hormones; D007529:Isoflavones; D048789:Phytoestrogens