CHOP/caspase-3 signal pathway involves in mitigative effect of selenium on lead-induced apoptosis via endoplasmic reticulum pathway in chicken testes

Abstract

Lead (Pb) is an environmental pollutant. Selenium (Se) has alleviative effect on Pb poisoning. However, mitigative effect of Se on Pb-induced apoptosis has not been unclear via endoplasmic reticulum (ER) pathway in chicken testes. The aim of this study was to investigate mitigative effect of Se on apoptosis induced by Pb poisoning via ER pathway in chicken testes. Sixty male chickens (7-day-old) were randomly divided into the control group offered drinking water (DW) and basic diet (BD) (0.49 mg/kg Se), the Se group offered DW and BD containing Na₂SeO₃ (SeBD) (1.00 mg/kg Se), the Pb group offered DW containing (CH₃OO)₂Pb (PbDW) (350.00 mg/L Pb) and BD, and the Pb + Se group offered PbDW and SeBD; and were fed for 90 days. The following contents were performed as follows: histology; antioxidant indexes (reduced glutathione (GSH), malondialdehyde (MDA), glutathione peroxidase (GPx), glutathione S-transferase (GST), and superoxide dismutase (SOD)); mRNA expressions of ER-related genes (glucose-related protein 78 (GRP78), protein kinase-like ER kinase (PERK), eukaryotic initiation factor 2α (eIF2α), activating transcription factor 4 (ATF4), and enhancer-binding protein homologous protein (CHOP)); and apoptosis-related genes (cysteine-aspartic protease (caspase)-3 and caspase-12) in chicken testes. The results indicated that Pb poisoning caused histological changes; increased MDA content; decreased the content of GSH and the activities of GPx, GST, and SOD; and upregulated mRNA expressions of the above five ER-related genes and two apoptosis-related genes in the chicken testes. Se alleviated Pb-induced oxidative stress, ER stress, and apoptosis via CHOP/caspase-3 signal pathway in the chicken testes.