The Protection of Selenium against Cadmium-Induced Cytotoxicity via the Heat Shock Protein Pathway in Chicken Splenic Lymphocytes

Xi Chen,Zi-Wei Zhang,Shi-Wen Xu,Yi-Hao Zhu,Xin-Yue Cheng

doi:10.3390/molecules171214565

Xi Chen, Zi-Wei Zhang + Show 3 more

Open Access

https://doi.org/10.3390/molecules171214565

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Abstract

Cadmium (Cd) is a heavy metal that poses a hazard to animal health due to its toxicity. Selenium (Se) is an important nutritional trace element. However, the potential protective effects of Se against Cd-induced toxicity remain to be elucidated. To investigate the cytotoxicity of Cd on bird immunocytes in vitro and the protective effects of Se against exposure to Cd, chicken splenic lymphocytes received Cd (10−6 mol/L), Se (10−7 mol/L), and the mixture of 10−7 mol/L Se and 10−6 mol/L Cd and were incubated for 12 h, 24 h, 36 h, 48 h, respectively. The transcription of heat shock protein (HSP) 27, HSP40, HSP60, HSP70 and HSP90 mRNA was tested by fluorescence quantitative PCR. The results showed that the mRNA expression of HSPs exposed to 10−6 mol/L Cd showed a sustained decrease at 12–48 h exposure. A statistically significant increase in the mRNA expression of HSPs in the case of Se group was observed, as compared to the control group of chicken splenic lymphocytes. Concomitantly, treatment of chicken splenic lymphocytes with Se in combination with Cd enhanced the mRNA expression of HSPs which were reduced by Cd treatment. This indicated that the protective effect of Se against the toxicity of Cd might, at least partially, be attributed to stimulation of the level of HSPs.

Highlights

Cadmium (Cd) is a heavy metal known to be both ubiquitous in natural environments and extremely toxic
No literature is available regarding the toxic effects of Cd through heat shock protein (HSP) pathway on the splenocytes of birds
The toxicity of Cd to chicken splenic lymphocytes was estimated by determination of HSP response

Summary

Introduction

Cadmium (Cd) is a heavy metal known to be both ubiquitous in natural environments and extremely toxic. Cd causes pleiotropic effects on organisms at both the molecular and cellular levels It binds to cysteine residues of proteins and induces oxidative stress [7]. Many HSPs, especially the 70 kDa family (HSP70), are expressed in response to diverse stressors, and increased synthesis of these inducible proteins is involved in the protection of stressed cells and organisms [16]. Exposure of cells to a chemical stress elicits an up-regulation of a number of cytoprotective systems [20], amongst which the heat shock response is one of the most studied [21] In this response, the synthesis of HSPs is up-regulated; these proteins play a role in maintaining protein structure/function by acting as molecular chaperones to assist the correct folding of damaged or newly synthesized proteins [22]. The present study was, carried out to determine whether Se supplementation could have a protective effect against the Cd-induced toxic effect in chicken splenic lymphocytes through the HSP pathway

Results and Discussion

Preparation of Chicken Splenic Lymphocytes Suspension and Treatment

Quantification of HSPs mRNA

Statistical Analyses

Conclusions