Background:
Formalin is widely used as tissue fixative and disinfectant. It contains reactive molecules which have been known for its cytotoxic effects, According to recent studies, formalin causes a change in the testicular and sperm structure; with the effects of
L-carnitine as an antioxidant.Objective: Our aim was to evaluate the effect of
L-carnitine on DNA structure,
Chromatin quality and
apoptosis in BALB/C mice treated with formalin.Materials and Methods: In this interventional study, 32 adult BALB/C mice (10-12 wk old; 30-35gr weight) were randomly divided into 4 groups of 8 mice each. The control group received no medicine. Sham group; received only serum normal saline 10 ml/kg intraperitoneally for 31 days. The 3rd group was exposed to formalin, 10 mg/kg injected intraperitoneally for 31 days. The 4th group were exposed to formalin, 10 mg/kg intraperitoneal injection daily and
L-carnitine (100 mg/kg solution) for up to 31 days. Then the mice were killed by spinal cord injury and sperm samples were taken and then sperm chromatin condensation and DNA integrity were assessed by four different tests including chromomycin A3 (CMA3), toluidine blue (TB), aniline blue (AB) and TUNEL for sperm apoptosis.Results: The results showed that formalin increase the percentage of sperm cells with abnormal chromatin (p≤0.05). In addition, in comparison with control group, we had a significant elevation in spermatozoa with residual histones (assessed by AB). With the aid of staining tests, we found that with using formalin in mice, there was a significant increase in DNA damage in comparison to the control group. In addition, with regard TUNEL test, the rate of reacted spermatozoa was increased significantly in
L-carnitine group when compared with the controls (p<0.05).Conclusion:
Formalin disturbs nuclear maturity and DNA integrity of spermatozoa. Therefore, the production of spermatozoa with less condensed chromatin and more apoptotic rate increases after formalin exposure and this may be one possible cause of infertility following formalin exposure, and
L-carnitine improve this so it can be used as a prophylaxis in these individuals.