Oral Administration of Reduced Coenzyme Q10 Ameliorates the Endocrine Disrupting Chemical Induced Sperm Toxicity in Rats
Aim Food additives and agricultural chemicals consumed in daily life can be endocrine disrupting chemicals (EDCs) for humans. EDCs have been reported to influence our genital function, learning ability and recognition. We have reported that the production of reactive oxygen species (ROS) precedes the decrease in sperm motility and/or numbers (FRR 2010) suggesting oxidative stress plays a key role. Therefore, we have studied the effects of a strong antioxidant, coenzyme Q 10 (CoQ10) on the rat sperm toxicity induced by diethylstilbestrol (DES) one of EDCs. Methods Drinking water containing DES (0.1 mg/L) CoQ10 (300 or 600 mg/kg/day; Kaneka Co. were given to Wistar rats (13 weeks old) for 8 weeks. The numbers and the motility of sperm, and lipid peroxidation products in the testicle were measured. Result Reduced CoQ10 was absorbed and transferred to rat blood and liver, but only a little to the testicle. Administration of DES decreased the number of sperm in the cauda epididymidis, and motility functions (curve line speed, and the head amplitude) Supplementation of reduced CoQ10 did not rescue the decline of sperm numbers. However, both the curved line speed and the head amplitude of the sperm which are important functions of fertilization were improved significantly by reduced CoQ10. HNE (4 hydroxy 2 nonenal) modified proteins (28 and 53 kDa) in the testicle were increased significantly by DES administration. Reduced CoQ10 significantly decreased HNE modified proteins. Conclusion Although the reduced CoQ10 supplementation to rats did not rescue the decline of total sperm numbers induced by DES administration, it significantly reduced oxidative stress in the testis and improved sperm function. These results suggested that the systemic absorption of reduced CoQ10 might inhibit oxidative stress of the testicle and dysfunction of the sperm.