title: HSL-knockout mouse testis exhibits class B scavenger receptor upregulation and disrupted lipid raft microdomains.
abstract: There is a tight relationship between fertility and changes in cholesterol metabolism during spermatogenesis. In the testis, class B scavenger receptors (SR-B) SR-BI, SR-BII, and LIMP II mediate the selective uptake of cholesterol esters from HDL, which are hydrolyzed to unesterified cholesterol by hormone-sensitive lipase (HSL). HSL is critical because HSL knockout (KO) male mice are sterile. The aim of the present work was to determine the effects of the lack of HSL in testis on the expression of SR-B, lipid raft composition, and related cell signaling pathways. HSL-KO mouse testis presented altered spermatogenesis associated with decreased sperm counts, sperm motility, and infertility. In wild-type (WT) testis, HSL is expressed in elongated spermatids; SR-BI, in Leydig cells and spermatids; SR-BII, in spermatocytes and spermatids but not in Leydig cells; and LIMP II, in Sertoli and Leydig cells. HSL knockout male mice have increased expression of class B scavenger receptors, disrupted caveolin-1 localization in lipid raft plasma membrane microdomains, and activated phospho-ERK, phospho-AKT, and phospho-SRC in the testis, suggesting that class B scavenger receptors are involved in cholesterol ester uptake for steroidogenesis and spermatogenesis in the testis.
authors.affiliation: Servicio de Bioquímica-Investigación, Hospital Universitario Ramón y Cajal, Instituto Ramón y Cajal de Investigación Sanitaria, Madrid, Spain.
authors.forename: María Emilia
authors.initials: ME
authors.lastname: Casado
authors.forename: Lydia
authors.initials: L
authors.lastname: Huerta
authors.forename: Ana Isabel
authors.initials: AI
authors.lastname: Ortiz
authors.forename: Mirian
authors.initials: M
authors.lastname: Pérez-Crespo
authors.forename: Alfonso
authors.initials: A
authors.lastname: Gutiérrez-Adán
authors.forename: Fredric B
authors.initials: FB
authors.lastname: Kraemer
authors.forename: Miguel Ángel
authors.initials: MÁ
authors.lastname: Lasunción
authors.forename: Rebeca
authors.initials: R
authors.lastname: Busto
authors.forename: Antonia
authors.initials: A
authors.lastname: Martín-Hidalgo
mesh_terms: D000818:Animals; D008297:Male; D021962:Membrane Microdomains / Q000378:metabolism*; D051379:Mice; D018345:Mice, Knockout; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051122:Scavenger Receptors, Class B / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction / Q000235:genetics; D013076:Sperm Count; D013091:Spermatogenesis / Q000235:genetics; D002787:Sterol Esterase / Q000172:deficiency* / Q000235:genetics / Q000378:metabolism; D013737:Testis / Q000378:metabolism*; D015854:Up-Regulation
chemical_list: D012333:RNA, Messenger; D051122:Scavenger Receptors, Class B; D002787:Sterol Esterase