A new application of nano-selenium: rescue of CK2 and mitochondria from oxidative stress to prevent cardiac hypertrophy.

Background: Excessive reactive oxygen species (ROS) and subsequent mitochondrial dysfunction are pivotal in initiating cardiac hypertrophy. To explore nano-selenium's (SeNP's) preventive potential against this condition, the authors evaluated chemically synthesized chitosan-SeNPs and biosynthesized Bacillus cereus YC-3-SeNPs in an angiotensin II (Ang II)-induced cardiac hypertrophy model. Methods: This investigation encompassed ROS measurement, mitochondrial membrane potential analysis, transmission electron microscopy, gene and protein expression analyses, protein carbonylation assays, serum antioxidant quantification and histological staining. Results: SeNPs effectively countered Ang II-induced cardiac hypertrophy by reducing ROS, restoring mitochondrial and protein kinase 2α (CK2-α) function, activating antioxidant pathways and enhancing serum antioxidant levels. Conclusion: This finding underscores SeNPs' role in attenuating Ang II-induced myocardial hypertrophy both in vitro and in vivo.

Enlargement of the heart is called cardiac hypertrophy; this is caused by too many reactive oxygen species, which are compounds that damage the mitochondria of cells. The mitochondria provide energy to cells and their disruption can cause a significantly negative effect on cells and the tissues and organs cells make up. Selenium is a type of metal that must be consumed in small amounts to stay healthy; it has antioxidant effects, meaning it can stop reactive oxygen species and potentially prevent cardiac hypertrophy. Nano-selenium (SeNP), consisting of tiny, spherical particles containing selenium, may be a more effective way of delivering selenium as an antioxidant to prevent cardiac hypertrophy. SeNPs were made synthetically and from a type of bacterium called Bacillus cereus; both SeNPs demonstrated antioxidant effects in heart cells taken from chicken embryos and live chickens. These results suggest that SeNPs could be developed into medication to combat cardiac hypertrophy.

Preparation, characterization, and antioxidant and antiapoptotic activities of biosynthesized nano­selenium by yak-derived Bacillus cereus and chitosan-encapsulated chemically synthesized nano­selenium.

Nano­selenium (SeNPs) is a red elemental selenium with extremely small particles, which can be absorbed by the body and has biological activity. Currently, the most commonly used synthetic methods for SeNPs are biosynthesis and chemical synthesis. In this study, YC-3-SeNPs were biosynthesized by a strain of yak-gut Bacillus cereus YC-3, and meanwhile, CST-SeNPs were chemically synthesized and encapsulated with chitosan. A series of characterizations proved that YC-3-SeNPs and CST-SeNPs are spherical particles with excellent stability, and both have an excellent ability to scavenge free radicals in vitro. The particles of YC-3-SeNPs were encapsulated with polysaccharides, fiber, and protein, and it was less toxic than that of CST-SeNPs. Additionally, YC-3-SeNPs and CST-SeNPs may inhibit H2O2-induced oxidative stress in cardiomyocytes by activating the Keap1/Nrf2/HO-1 signaling pathway thereby scavenging ROS. Meanwhile, they may exert anti-apoptotic activity in cardiomyocytes by stabilizing mitochondrial membrane potential (∆Ψm) and balancing Bax/Bcl-2 protein, thereby reducing the protein expression of Cyt-c and Cleaved-caspase 3. Given the above, YC-3-SeNPs and CST-SeNPs with excellent antioxidant and anti-apoptotic activities may have broad application potential in the field of cardiovascular diseases.