title: Effect of in vivo chronic exposure to clotrimazole on zebrafish testis function.
abstract: Clotrimazole is an azole fungicide used as a human pharmaceutical that is known to inhibit cytochrome P450 (CYP) enzymatic activities, including several steroidogenic CYP. In a previous report, we showed that a 7-day exposure to clotrimazole induced the expression of genes related to steroidogenesis in the testes as a compensatory response, involving the activation of the Fsh/Fshr pathway. In this context, the aim of the present study was to assess the effect of an in vivo 21-day chronic exposure to clotrimazole (30-197 μg/L) on zebrafish testis function, i.e., spermatogenesis and androgen release. The experimental design combined (1) gene transcript levels measurements along the brain-pituitary-gonad axis, (2) 11-ketotestosterone (11-KT) quantification in the blood, and (3) histology of the testes, including morphometric analysis. The chronic exposure led to an induction of steroidogenesis-related genes and fshr in the testes as well as fshβ in the pituitary. Moreover, increases of the gonadosomatic index and of the volume proportion of interstitial Leydig cells were observed in clotrimazole-exposed fish. In accordance with these histological observations, the circulating concentration of 11-KT had increased. Morphometric analysis of the testes did not show an effect of clotrimazole on meiotic (spermatocytes) or postmeiotic (spermatids and spermatozoa) stages, but we observed an increase in the number of type A spermatogonia, in agreement with an increase in mRNA levels of piwil1, a specific molecular marker of type A spermatogonia. Our study demonstrated that clotrimazole is able to affect testicular physiology and raised further concern about the impact of clotrimazole on reproduction.
authors: Direction des Risques Chroniques, Pôle VIVA, Unité d'écotoxicologie in vitro et in vivo, INERIS, Parc Technologique Alata, BP2, 60550 Verneuil-en-Halatte, France.
authors: Damien
authors: D
authors: Baudiffier
authors: Nathalie
authors: N
authors: Hinfray
authors: Catherine
authors: C
authors: Ravaud
authors: Nicolas
authors: N
authors: Creusot
authors: Edith
authors: E
authors: Chadili
authors: Jean-Marc
authors: JM
authors: Porcher
authors: Rüdiger W
authors: RW
authors: Schulz
authors: François
authors: F
authors: Brion
mesh_terms: D000728:Androgens / Q000097:blood; D000818:Animals; D000935:Antifungal Agents / Q000494:pharmacology*; D002851:Chromatography, High Pressure Liquid; D003022:Clotrimazole / Q000494:pharmacology*; D004797:Enzyme-Linked Immunosorbent Assay; D029941:Fish Proteins / Q000235:genetics / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D008297:Male; D060888:Real-Time Polymerase Chain Reaction; D013091:Spermatogenesis / Q000187:drug effects; D013737:Testis / Q000033:anatomy & histology / Q000187:drug effects* / Q000201:enzymology; D013739:Testosterone / Q000031:analogs & derivatives / Q000097:blood; D014874:Water Pollutants, Chemical / Q000494:pharmacology*; D015027:Zebrafish / Q000235:genetics / Q000378:metabolism*
chemical_list: D000728:Androgens; D000935:Antifungal Agents; D029941:Fish Proteins; D014874:Water Pollutants, Chemical; D013739:Testosterone; D003022:Clotrimazole; C003600:11-ketotestosterone