Green Synthesized BSA-Coated Selenium Nanoparticles Inhibit Bacterial Growth While Promoting Mammalian Cell Growth.

BACKGROUND: Selenium is an essential trace element that is critical for many biological processes. Selenium nanoparticles (SeNPs) have shown more promise than other forms of selenium due to their low cytotoxicity and high bioavailability. METHODS: In this work, a one-step method was demonstrated for fabricating bovine serum albumin (BSA) stabilized SeNPs using ascorbic acid as the reductant. Human dermal fibroblasts were used to assess mammalian cytotoxicity, and Staphylococcus aureus and Escherichia coli were used to assess antibacterial performance. RESULTS: These SeNPs demonstrated increased fibroblast growth and reduced Staphylococcus aureus growth with a fibroblast IC50 value (>681 µg/mL) 1 order of magnitude higher than that for bacteria at day 1. CONCLUSION: This study demonstrated the promise of this synthesis process in achieving controllable selenium nanoparticle sizes without the use of strong basic solvents for improved antibacterial properties.

Selenium Nanoparticle Protection of Fibroblast Stress: Activation of ATF4 and Bcl-xL Expression.

BACKGROUND: In recent years, selenium nanostructures have been researched due to their antibacterial properties, low toxicity to mammalian cells, and high biological efficacy. However, the clinical implementation of the use of selenium has received mixed results, and there is much work needed to improve the understanding of the biological mechanisms involved in the observed cellular responses. MATERIALS AND METHODS: In this work, an investigation into the mechanistic pathways of selenium nanoparticles (SeNPs) in biological systems was conducted by studying the changes in gene expression of ATF4, Bcl-xL, BAD2, HSP70, and SOD2 in non-cancerous human dermal fibroblasts (HDF) under oxidative stress, nutrient deprivation stress, and no treatment (control) conditions. RESULTS: This study revealed that SeNP incubation led to reduced internal reactive oxygen species (ROS) generation for all conditions tested, thus, providing a protective environment for HDF. At the stress conditions, the expression of ATF4 and Bcl-xL increased for cells treated with SeNP incubation, leading to attenuation of the cells under stress. These results also hint at reductive stress causing a detrimental impact to cell proliferation under routine cell passaging conditions. CONCLUSION: In summary, this study highlights some possible mechanistic pathways implicated in the action of SeNPs that warrant further investigation (specifically, reducing stress conditions for HDF) and continues to support the promise of SeNPs in a wide range of medical applications.