Melamine and/or formaldehyde exposures affect steroidogenesis via alteration of StAR protein and testosterone synthetic enzyme expression in male mice.
The reproductive effects of melamine and formaldehyde, either alone or in combination, on mature male Swiss mice were investigated. The animals were orally administered melamine (50mg/kg/day), formaldehyde (25mg/kg/day), a mixture of melamine and formaldehyde, or a vehicle control for 65 consecutive days. As a result, the deterioration of sperm characteristics and inhibition of testicular enzyme activity were observed in the melamine- and formaldehyde-exposed groups. In addition, testosterone and luteinizing hormone levels were significantly reduced in the melamine but not in the formaldehyde-exposed group, which correlated with down-regulation of transcription levels of steroidogenic-related genes. Histopathologically, both compounds caused lesions in the testes. However, the co-exposure reduced the induced alterations in spermatogenesis, steroidogenesis, and testicular architecture that were obviously observed in the melamine-exposed group. Consequently, we demonstrated that melamine exhibited more pronounced reproductive impact in comparison with formaldehyde. In addition, formaldehyde was able to substantially temper the melamine -induced reproductive toxic effect.
Forensic Medicine and Toxicology Department, Faculty of Veterinary Medicine, Zagazig University, Egypt. Electronic address: dr_samahkhalil@yahoo.com.
Samah R
SR
Khalil
Animal Wealth Development Department, Faculty of Veterinary Medicine, Zagazig University, Egypt.
Ashraf
A
Awad
Histology and Cytology Department, Faculty of Veterinary Medicine, Zagazig University, Egypt.
Sozan A
SA
Ali
D000818:Animals; D005557:Formaldehyde / Q000633:toxicity*; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D007986:Luteinizing Hormone / Q000378:metabolism; D008297:Male; D051379:Mice; D010750:Phosphoproteins / Q000235:genetics*; D013076:Sperm Count; D013094:Spermatozoa / Q000187:drug effects; D013737:Testis / Q000187:drug effects / Q000201:enzymology*; D013739:Testosterone / Q000378:metabolism*; D014227:Triazines / Q000633:toxicity*; D000098682:Steroidogenic Acute Regulatory Protein
D010750:Phosphoproteins; D014227:Triazines; D000098682:Steroidogenic Acute Regulatory Protein; D005557:Formaldehyde; D013739:Testosterone; D007986:Luteinizing Hormone; C011907:melamine
3β-Hydroxysteroid dehydrogenase type 1; Cytochrome P450 side-chain cleavage enzyme; Formaldehyde; Melamine; Steroidogenic acute regulatory protein; Steroidogenic-related genes