Protection mechanism of Se-containing protein hydrolysates from Se-enriched rice on Pb2+-induced apoptosis in PC12 and RAW264.7 cells

This study aimed to investigate the protection mechanism of Se-containing protein hydrolysates (SPH) from Se-enriched rice on Pb 2+ -induced apoptosis in PC12 and RAW264.7 cells. Results showed that SPHs could alleviate Pb 2+ -induced morphological changes of apoptosis and the loss of mitochondrial transmembrane potential in both cell types. Besides this, SPHs could significantly reduce the activation of caspase-3, -8, -9 induced by Pb 2+ , reverse the Pb 2+ -induced upregulation of Bax and release of cytochrome C, and downregulate Bcl-2 in cells. HPLC-ICP-MS and SEC-HPLC assays showed that SPHs were low molecular weight peptides (229.4–534.9   Da), and the major Se species found in SPHs was SeMet. Taken together, these findings suggested that SPHs could possibly protect the cells against Pb 2+ -induced apoptosis via a caspase-dependent mitochondrial pathway, and the primary effective constituents in SPHs were SeMet and Se-containing peptides, suggesting that SPHs might be a novel potential candidate to improve the health of people with Se deficiency or in Pb-contaminated areas.