title: The effects on steroidogenesis and histopathology of adult male Japanese quails (Coturnix coturnix japonica) testis following pre-pubertal exposure to di(n-butyl) phthalate (DBP).
abstract: In the present study, we have investigated the effects of 30-day dietary (pre-pubertal) exposure to different doses (0 (control), 1, 10, 50, 200 and 400 mg/kg bodyweight/day) of di(n-butyl) phthalate (DBP) on Leydig cells of adult male Japanese quails by quantifying the transcript levels for P450 side-chain cleavage (p450scc), P450c17 (CYP17), and 3β- and 17β-hydroxysteroid dehydrogenase (hsd) using quantitative (real-time) polymerase chain reaction (qRT-PCR). In addition, the plasma testosterone levels were analysed using radioimmunoassay (RIA) and testis was examined for evidence of gross pathology and histopathology. Our data showed that pre-pubertal exposure to DBP produced alterations in testicular architecture as evident by poorly developed or mis-shaped testis, and altered spermatogenesis due to tubular degeneration and atrophy of seminiferous tubules especially in the high DBP dose (200 and 400 mg/kg) treated groups. In addition, DBP altered several key enzymes involved in testicular steroidogenesis pathways in an apparent dose-dependent manner. For example, biphasic effects of DBP were observed for P450scc and 3β-hsd mRNA, that were generally increasing at low dose 10 mg/kg, and thereafter, an apparent dose-dependent decrease between 50 and 400mg/kg. The steroidogenic acute regulatory (StAR) protein was at the lowest detectable limits and therefore not quantifiable. These effects did not parallel the non-significant changes observed for plasma testosterone levels. The present data is consistent with previous reports showing that DBP modulates Leydig cell steroidogenesis in several species, with a potential negative effect on reproduction in those avian species that are vulnerable to endocrine disrupting chemicals.
authors.affiliation: Department of Anatomy and Physiology, University of Pretoria, Private Bag X04, Onderstepoort 0110, South Africa; Department of Veterinary Anatomy, Ahmadu Bello University, Zaria, Nigeria.
authors.forename: Umar M
authors.initials: UM
authors.lastname: Bello
authors.affiliation: Department of Anatomy and Physiology, University of Pretoria, Private Bag X04, Onderstepoort 0110, South Africa.
authors.forename: Mary-Catherine
authors.initials: MC
authors.lastname: Madekurozwa
authors.affiliation: Department of Anatomy and Physiology, University of Pretoria, Private Bag X04, Onderstepoort 0110, South Africa.
authors.forename: Herman B
authors.initials: HB
authors.lastname: Groenewald
authors.affiliation: Department of Anatomy and Physiology, University of Pretoria, Private Bag X04, Onderstepoort 0110, South Africa; Department of Anatomy, Physiology and Pharmacology, School of Veterinary Medicine, St. George's University, True Blue, St George's, Grenada.
authors.forename: Tom A
authors.initials: TA
authors.lastname: Aire
authors.affiliation: Department of Biology, Norwegian University of Science and Technology (NTNU), Høgskoleringen 5, 7491 Trondheim, Norway. Electronic address: arukwe@bio.ntnu.no.
authors.forename: Augustine
authors.initials: A
authors.lastname: Arukwe
mesh_terms: D000818:Animals; D001284:Atrophy; D030161:Avian Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D001715:Bird Diseases / Q000139:chemically induced* / Q000378:metabolism / Q000473:pathology; D002786:Cholesterol Side-Chain Cleavage Enzyme / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D003370:Coturnix; D003993:Dibutyl Phthalate / Q000008:administration & dosage / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D052244:Endocrine Disruptors / Q000008:administration & dosage / Q000633:toxicity*; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects*; D059165:Hormesis; D006913:Hydroxysteroid Dehydrogenases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D007246:Infertility / Q000139:chemically induced / Q000378:metabolism / Q000473:pathology / Q000662:veterinary*; D007985:Leydig Cells / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D008297:Male; D009929:Organ Size / Q000187:drug effects; D010750:Phosphoproteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D010968:Plasticizers / Q000008:administration & dosage / Q000633:toxicity; D011897:Random Allocation; D015203:Reproducibility of Results; D013091:Spermatogenesis / Q000187:drug effects; D013737:Testis / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism / Q000473:pathology; D000098682:Steroidogenic Acute Regulatory Protein
chemical_list: D030161:Avian Proteins; D052244:Endocrine Disruptors; D010750:Phosphoproteins; D010968:Plasticizers; D000098682:Steroidogenic Acute Regulatory Protein; D003993:Dibutyl Phthalate; D006913:Hydroxysteroid Dehydrogenases; D002786:Cholesterol Side-Chain Cleavage Enzyme
keywords: Di-(n-butyl) phthalate; Endocrine disruption; Leydig cell; Male Japanese quails; Steroidogenesis