Effects Of Zearalenone On The Blood-testis Barrier Structure And Functions

There are more and more Mycotoxin-Contaminated crops in the world, among them zearalenone is one of the most mycotoxins of the agricultural economy importance. Not only zearalenone can cause systemic disease, but also reduce livestock production and increase investment in health care and veterinary medical. In recent years, the reproductive toxicity of zearalenone attracted widespread attention. The blood-testis barrier is hot spot in the current study of the damage to male reproductive system of exogenous poison. Is zearalenone on male reproductive toxicity through disruption of the blood-testis barrier? It is need to further explore and discuss the toxicity mechanisms.In the acute attack trial,95 clean grade 8 week age adult male Kunming mice were randomly divided into 5 groups and exposed to intraperitoneal (i.p.) injection of ZEN at 25 mg/kg,50 mg/kg,75 mg/kg body weight (b.w.), and solvent, respectively for 5 days. The mice were sacrified at the 6th day after eyeball blood sampling. The testis and epididymis viscera indexes, semen quality, testis enzyme activity, serum concentrations of testosterone and estrogen, and expressions of Vim、Cldnl 1 and N-cad mRNA were detected. In the chronic attack trial,75 clean grade 8 week age adult male Kunming mice were randomly divided into 5 groups and exposed to ZEN at 25 mg/kg, and 50 mg/kg, and 75 mg/kg ZEN, and oil by oral route respectively for 28 days. The mice were sacrified after eyeball blood sampling. In addition to checking the above indicators, liver and kidney function indexes, testis tissue slices and expressions of Vim、Cldn11、 N-cad、StAR and Cyp11al mRNA were detected and observed.The acute attack results showed that compared with the control group, ZEN significantly decreased the body weight, semen quality, increased the testis enzyme activity(AKP, ACP, LDH) and decreased serum concentrations of testosterone and estrogen, significantly improved the Vim and Cldnl1 expressions, but decreased N-cad. The chronic attack results showed that compared with the control group, ZEN significantly decreased the semen quality, serum concentrations of testosterone and estrogen, damaged liver and kidney function, slightly increased AKP and ACP activities, declined LDH and y-GT, reduced spermatogenic cells and disorderly arranged in high dose group, significantly decreased the Vim、StAR and Cypl1al expressions, and slightly increased the expression levels of Cldnl 1 and N-cad.These results suggested that acute and chronic attack effects of ZEN could display sperm quality and significantly decrease the concentration of serum testosterone and estradiol, affect the activities of the testicles marker enzymes. Acute attack effects of ZEN could increase Vim and Cldnl 1 mRNA expressions and reduce N-cad expression, which may be associated with the body’s self-healing mechanisms of adaptation, by strengthening the expressions of key genes to extend BTB reconstruction period for protecting spermatogenic cells from exogenous toxins. Chronic attack effects of ZEN could decrease Vim, StAR and Cypllal mRNA expressions, improve slightly Cldnll and N-cad expressions, which indicated that ZEN could cause serious damage to the blood-testis barrier, through the body’s self-healing adaptive reaction, but could not completely withstand the damage and invasion of the poison.