Vitamin B₁₂-induced spermatogenesis recovery in cimetidine-treated rats: effect on the spermatogonia number and sperm concentration

Abstract

The H2-receptor antagonist cimetidine is an antiulcer drug also used for the treatment of cancer due to its antiangiogenic effect. However, this drug has caused structural changes in the seminiferous tubules. Vitamin B12 has been used as a therapeutic agent for the treatment of male infertility. The supplementation of rats with vitamin B12 during cimetidine treatment has recovered the damaged seminiferous tubules, but how this vitamin restores the seminiferous epithelium has not been clarified. In this study, we evaluated whether vitamin B12 improves the number of spermatogonia, spermatocytes, and sperm concentration in cimetidine-treated rats. Adult male rats were treated for 50 days as follows: cimetidine group received 100 mg kg−1 b.w. of cimetidine, cimetidine-B12 group received cimetidine and 3 μg of vitamin B12-hydroxocobalamin, B12 group received only 3 μg of vitamin, and control group received saline. Sperm concentration was calculated and historesin-embedded testes sections were used for the quantitative analyses of spermatogonia (A; In/B) and spermatocytes. TUNEL method and PCNA immunofluorescence were performed. Cimetidine caused a significant reduction in sperm concentration. TUNEL-positive spermatogonia and spermatocytes were correlated to a significant reduction in the number of these cells. In cimetidine-B12 group, sperm concentration was higher than cimetidine group and a significant increase in the number of spermatogonia (stages II–VI) was correlated to a high incidence of PCNA-immunolabeled spermatogonia and spermatocytes. The results show that the supplementation of rats with vitamin B12 during cimetidine treatment increases sperm concentration and exerts a potential effect in the recovery of spermatogonia and spermatocytes.

Seminiferous epithelium damage after short period of busulphan treatment in adult rats and vitamin B12 efficacy in the recovery of spermatogonial germ cells

“…Another important point that could explain why the number of spermatogonia did not increase in B 12 G is the balance between apoptosis and cell proliferation when the tissue is in homoeostasis. In rats supplemented with vitamin B 12 , numerous PCNA-immunolabelled spermatogonia and early primary spermatocytes have been observed in parallel to a high incidence of TUNEL positivity in these same germ cells (Beltrame & Sasso-Cerri 2016). As mitotic divisions of spermatogonia are synchronized to meiotic divisions of spermatocytes, the concomitant presence of apoptotic spermatogonia and apoptotic spermatocytes in the same tubule sections might also indicate that this synchronization is carried out through the synchronized control of mitotic and meiotic checkpoints (Blanco-Rodr ıguez et al 2003).…”

“…A high incidence of PCNA-positive spermatogonia and spermatocytes has been shown in the testes of rats treated with histamine H 2 receptor antagonistcimetidineand supplemented with vitamin B 12 (Beltrame et al 2011). Moreover, a detailed quantification of spermatogonial cell types in stage-specific seminiferous tubules showed that the supplementation of rats with vitamin B 12 during cimetidine treatment for 52 days seems to stimulate specifically type A spermatogonia mitotic activity, which in turn recovers the number of spermatogonia and spermatocytes (Beltrame & Sasso-Cerri 2016). In the present study, the number of PCNA-immunolabelled spermatogonia was higher in the animals from Bu/B 12 G in comparison with BuG, suggesting that vitamin B 12 was able to induce spermatogonial mitotic activity.…”

“…This result may be related to the fact that B complex vitamins are water-soluble vitamins, and the excess of these vitamins is excreted in the urine and stored in liver when the organism is supplied (Andr es et al 2004). In rats supplemented with vitamin B 12 , numerous PCNA-immunolabelled spermatogonia and early primary spermatocytes have been observed in parallel to a high incidence of TUNEL positivity in these same germ cells (Beltrame & Sasso-Cerri 2016). Otherwise, the supplementation would be useful and effective under pathological conditions in which spermatogenic process is devoid of vitamin.…”

Reduced levels of stromal sex hormone-binding globulin and androgen receptor dysfunction in the sperm storage region of the rat epididymis

“…due to Leydig cell apoptosis (Beltrame et al 2015) as well as reduction in the testosterone release by pig Leydig cells in vitro (Goda et al 2017). Reduction in the sperm concentration (Beltrame & Sasso-Cerri 2016) together with structural and functional disorders in the testes (França et al 2000, Sasso-Cerri & Miraglia 2002, Sasso-Cerri & Cerri 2008, Beltrame et al 2011, 2012) and vas deferens (Koshimizu et al 2013) have also been caused by cimetidine, indicating that this drug acts as an androgen disrupter in the male reproductive system. In the present study, in addition to the reduction in the testosterone levels, cimetidine impaired the epididymal sperm storage region histophysiology by reducing the collagen content and the stromal SHBG levels and by impairing the AR nuclear import in the epithelial cells.…”

“…In rats treated for long periods, this drug has caused testicular changes, such as reduction of the seminiferous epithelium due to apoptosis of germ cells and Sertoli cells (Sasso- Cerri & Miraglia 2002, Sasso-Cerri & Cerri 2008, Beltrame et al 2011, and disorganization of peritubular tissue (França et al 2000, Sasso-Cerri & Cerri 2008. The treatment of rats with 100 mg/kg of cimetidine for a long period has caused reduction in serum testosterone levels (Beltrame et al 2015) and in sperm concentration (Beltrame & Sasso-Cerri 2016). This drug has also impaired the vas deferens structure associated with the reduction of AR immunoexpression in muscle cells (Koshimizu et al 2013).…”