The acute effects of mono(2-ethylhexyl)phthalate (MEHP) on testes of prepubertal Wistar rats.

A single oral dose of 400 mg/kg body weight of mono(2-ethylhexyl)phthalate (MEHP), the testis toxic metabolite of di(2-ethylhexyl)phthalate, was given to 28-day-old male Wistar rats and the testis toxic effects were investigated 3,6, and 12 h after exposure. Detachment and sloughing of germ cells were observed, and in the Sertoli cells the cytoplasmatic intermediate filament vimentin collapsed. In the immunohistochemical investigation the androgen receptor distribution was unchanged between the control group and treated groups. The expression of the testosterone-repressed-prostatic-message-2 gene in rat testis increased after 3 h, but returned to control levels after 6 and 12 h. Caspase-3 activity increased 3 and 12 h after MEHP exposure. This increase could not be correlated to an increase in DNA fragmentation or increase in apoptotic numbers of germ cells. In conclusion, the effect of MEHP in testis is apparently not involving the androgen receptor. Vimentin localisation in the Sertoli cells, and increased levels of caspase-3 activity appear to be sensitive and early markers of MEHP testis toxicity.

[1]  T. Wheeler,et al.  In situ end-labeling of human testicular tissue demonstrates increased apoptosis in conditions of abnormal spermatogenesis. , 1997, Fertility and sterility.

[2]  J. Heindel,et al.  Inhibition of FSH-stimulated cAMP accumulation by mono(2-ethylhexyl) phthalate in primary rat Sertoli cell cultures. , 1989, Toxicology and applied pharmacology.

[3]  J. Reel,et al.  Effects of di(2-ethylhexyl) phthalate on the gonadal pathophysiology, sperm morphology, and reproductive performance of male rats. , 1986, Environmental health perspectives.

[4]  L. Gray,et al.  The plasticizer diethylhexyl phthalate induces malformations by decreasing fetal testosterone synthesis during sexual differentiation in the male rat. , 2000, Toxicological sciences : an official journal of the Society of Toxicology.

[5]  K. Shiota,et al.  Involvement of germ cell apoptosis in the induction of testicular toxicity following hydroxyurea treatment. , 1999, Toxicology and applied pharmacology.

[6]  N. Thornberry.  Interleukin-1 beta converting enzyme. , 1994, Methods in enzymology.

[7]  L. Agnati,et al.  Regional and cellular distribution within the rat prostate of two mRNA species undergoing opposite regulation by androgens. , 1992, The Journal of endocrinology.

[8]  S. Nagata,et al.  Sequential activation of ICE-like and CPP32-like proteases during Fas-mediated apoptosis , 1996, Nature.

[9]  Y. Furuya,et al.  Differential gene regulation during programmed death (apoptosis) versus proliferation of prostatic glandular cells induced by androgen manipulation. , 1993, Endocrinology.

[10]  L. Gray,et al.  Administration of potentially antiandrogenic pesticides (procymidone, linuron, iprodione, chlozolinate, p,p′-DDE, and ketoconazole) and toxic substances (dibutyl- and diethylhexyl phthalate, PCB 169, and ethane dimethane sulphonate) during sexual differentiation produces diverse profiles of reproduc , 1999, Toxicology and industrial health.

[11]  K. Mitsumori,et al.  Involvement of apoptosis in the rat germ cell degeneration induced by nitrobenzene , 1998, Archives of Toxicology.

[12]  Patrick R. Griffin,et al.  Identification and inhibition of the ICE/CED-3 protease necessary for mammalian apoptosis , 1995, Nature.

[13]  J. Lakins,et al.  Genomic organization and expression of the rat TRPM-2 (clusterin) gene, a gene implicated in apoptosis. , 1993, The Journal of biological chemistry.

[14]  V. Valli,et al.  Subchronic oral toxicity of di-n-octyl phthalate and di(2-Ethylhexyl) phthalate in the rat. , 1997, Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association.

[15]  P. Foster,et al.  Disruption of androgen-regulated male reproductive development by di(n-butyl) phthalate during late gestation in rats is different from flutamide. , 1999, Toxicology and applied pharmacology.

[16]  E. Nieschlag,et al.  Identification of male germ cells undergoing apoptosis in adult rats. , 1995, Journal of reproduction and fertility.

[17]  D. Phillips,et al.  Changes in the distribution of intermediate filaments in rat Sertoli cells during the seminiferous epithelium cycle and postnatal development , 1997, The Anatomical record.

[18]  K. Boekelheide,et al.  THE FAS SYSTEM IS A KEY REGULATOR OF GERM CELL APOPTOSIS IN THE TESTIS , 1997 .

[19]  P. Albro,et al.  Absorption, metabolism, and excretion of di(2-ethylhexyl) phthalate by rats and mice. , 1986, Environmental health perspectives.

[20]  L L Needham,et al.  Levels of seven urinary phthalate metabolites in a human reference population. , 2000, Environmental health perspectives.

[21]  J. M. Kim,et al.  Caspase-3 activation is required for Leydig cell apoptosis induced by ethane dimethanesulfonate. , 2000, Endocrinology.

[22]  R. Swerdloff,et al.  Involvement of apoptosis in the induction of germ cell degeneration in adult rats after gonadotropin-releasing hormone antagonist treatment. , 1995, Endocrinology.

[23]  J. Richburg,et al.  Participation of the Fas-signaling system in the initiation of germ cell apoptosis in young rat testes after exposure to mono-(2-ethylhexyl) phthalate. , 1999, Toxicology and applied pharmacology.

[24]  C. Martínez-García,et al.  Apoptosis pattern elicited by several apoptogenic agents on the seminiferous epithelium of the adult rat testis. , 1998, Journal of andrology.

[25]  K. Boekelheide,et al.  Mono-(2-ethylhexyl) phthalate rapidly alters both Sertoli cell vimentin filaments and germ cell apoptosis in young rat testes. , 1996, Toxicology and applied pharmacology.

[26]  A. Blaschke,et al.  Apoptotic DNA fragmentation is detected by a semi-quantitative ligation-mediated PCR of blunt DNA ends , 1997, Cell Death and Differentiation.

[27]  C. Rivier,et al.  Apoptosis in testis germ cells: developmental changes in gonadotropin dependence and localization to selective tubule stages. , 1995, Endocrinology.

[28]  N. Rosemblit,et al.  Regulators for the rat clusterin gene: DNA methylation and cis-acting regulatory elements. , 1994, Journal of molecular endocrinology.

[29]  G. Trimarchi,et al.  Oral toxicity of bis(2-ethylhexyl) phthalate during pregnancy and suckling in the Long-Evans rat. , 1998, Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association.

[30]  B. Huppertz,et al.  The apoptosis cascade — morphological and immunohistochemical methods for its visualization , 1999, Anatomy and Embryology.

[31]  W. Awara,et al.  Deltamethrin-induced testicular apoptosis in rats: the protective effect of nitric oxide synthase inhibitor. , 1999, Toxicology.

[32]  D. D. de Rooij,et al.  Isolation and characterization of all‐trans‐retinoic acid–responsive genes in the rat testis , 1998, Molecular reproduction and development.