Runjing extract promotes spermatogenesis in rats with ornidazole-induced oligoasthenoteratozoospermia through extracellular signal-regulated kinase signalling, and regulating vimentin expression.

Objective: To investigate the efficacy of Runjing (RJ) extract on oligoasthenoteratozoospermia (OAT) induced by ornidazole (ORN) in rats, and to study the underlying mechanism.

Methods: Twenty-four adult male Sprague-Dawley rats were treated with normal saline (control), ORN (OAT model), ORN + 4.725 g·kg－1·d－1 RJ extract (low-dose) and ORN+ 18.9 g·kg－1·d－1 RJ extract (high-dose) for 4 weeks. The rats were then euthanized and sperm and testis samples were collected for analysis. Sperm count, motility and morphology were calculated by sperm suspension from cauda epididymis. Testicular histopathological changes were analyzed by hematoxylin and eosin staining and TdT mediated dUTP nick end labelling. Moreover, the expression of vimentin and extracellular signal-regulated kinase (ERK) were examined through Western blot, and the distribution of vimentin was detected via immunohistochemistry.

Results: ORN successfully induces seminiferous epithelium injury, cellular apoptosis, and finally OAT (P < 0.05). However, both low-dose and highdose RJ extract partially rescues the phenotypes (P < 0.05). Moreover, the expressions of vimentin and ERK were significantly altered in ORN testes (all P < 0.001), while RJ extract partially reversed these effects (P < 0.01 or P < 0.001).

Conclusion: RJ extract can help maintain spermatogenesis through ERK signalling, and regulating vimentin expression.