Age-dependent loss of sperm production in mice via impaired lysophosphatidic acid signaling.
Approximately half of all infertility cases can be attributed to male reproductive dysfunction for which low sperm count is a major contributing factor. The current study identified receptor-mediated lysophosphatidic acid (LPA) signaling as a new molecular component influencing male fertility. LPA is a small signaling phospholipid, the effects of which are mediated through at least five G protein-coupled receptors, named LPA 1-5. LPA1/2/3, but not LPA4/5, show high expression in mouse testis. Mice deficient in LPA1/2/3 showed a testosterone-independent reduction of mating activity and sperm production, with an increased prevalence of azoospermia in aging animals. A significant increase of germ cell apoptosis also was observed in testes. Germ cell apoptosis led to a reduction in germ cell proliferation. These data demonstrate a novel in vivo function for LPA signaling as a germ cell survival factor during spermatogenesis.
Ye
Xiaoqin
X
Department of Molecular Biology, The Helen L. Dorris Child and Adolescent Neuropsychiatric Disorder Institute, The Scripps Research Institute, La Jolla, California 92037, USA.
Skinner
Michael K
MK
Kennedy
Grace
G
Chun
Jerold
J
D000367:Age Factors; D000818:Animals; D049109:Cell Proliferation; D005260:Female; D008246:Lysophospholipids / Q000502:physiology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D010766:Phosphorylation; D049368:Receptors, Lysophosphatidic Acid / Q000235:genetics / Q000378:metabolism; D012726:Sexual Behavior, Animal / Q000502:physiology; D015398:Signal Transduction / Q000235:genetics* / Q000502:physiology; D013076:Sperm Count; D013091:Spermatogenesis / Q000235:genetics* / Q000502:physiology; D013094:Spermatozoa / Q000166:cytology / Q000378:metabolism / Q000502:physiology; D013737:Testis / Q000166:cytology / Q000378:metabolism; D013739:Testosterone / Q000097:blood
D008246:Lysophospholipids; D049368:Receptors, Lysophosphatidic Acid; D013739:Testosterone; D048052:Mitogen-Activated Protein Kinase 3; C032881:lysophosphatidic acid