zinc and low-dose of cadmium protect sertoli cells against toxic-dose of cadmium: the role of metallothionein

background: the impact of cadmium (cd) on male infertility may be related to the interaction with metal-binding proteins known as metallothioneins (mts). trace elements like zinc (zn) have protective effects on testicular damage induced by cd. objective: we determined the effect of zn and low-dose cd pre-treatment on the expression of mt1 and mt2 genes on testicular sertoli cells. materials and methods: the cultured tm4 mouse sertoli cells were treated with 50 μm znso4 (zn pre-treated group; znpg), 2 μm cdcl2 (cd pre-treated group; cdpg), or distilled water (dw pre-treated group; dwpg). after 18 hour, all of these groups were exposed to 100 μm cdcl2 for different periods of time (1, 2, 3, and 6 hours). there was also a control group for all three groups, which was treated only with distilled water (without cd or zn pre-treatment). cellular viability, zn and cd concentrations and gene expression were assessed by mtt, atomic absorption spectrometry and real time pcr methods, respectively. results: the expression of mt1 and mt2 genes in znpg, cdpg, and dwpg was greater than the control group (p=0.02 and p=0.01, respectively). cd concentrations in cdpg and dwpg were greater than the control group (p=0.00). expression of both genes in znpg and cdpg increased after 3 hours of treatment and cd concentration decreased simultaneously, which was more obvious in znpg. conclusion: zn and short term low-dose cd pre-treatment might reduce the adverse effects of cd by increasing expression of mts genes in sertoli cells. the protective effect of zn was stronger than cd.