Poria cocos Polysaccharide-Modified Selenium Nanoparticles: Structural Characterization, Stability, and In Vitro Antioxidant and Anti-Inflammatory Activity Studies

TL;DR

Researchers developed stable selenium nanoparticles modified with a polysaccharide from Poria cocos, which showed antioxidant and anti-inflammatory effects in cell studies.

Contribution

The novel use of Poria cocos polysaccharide to modify Se NPs improves stability and biological activity.

Findings

PCP-Se NPs showed excellent stability in storage and salt ion environments.

PCP-Se NPs effectively scavenged free radicals and reduced inflammation in RAW264.7 cells.

The nanoparticles maintained mitochondrial function and reduced oxidative stress markers.

Abstract

Selenium nanoparticles (Se NPs) have received increasing attention as a new alternative source to other forms of selenium in nutritional dietary supplements; however, the limited stability and pronounced tendency of selenium nanoparticles (Se NPs) to aggregate in aqueous environments have significantly constrained their practical applications. In this study, Poria cocos polysaccharide-modified Se NPs (PCP-Se NPs) were synthesized by the selenite/ascorbic acid chemical reduction method. PCP-Se NPs exhibited a uniformly dispersed spherical morphology with an average particle size of 66.64 ± 0.30 nm, and displayed an amorphous crystal structure. Compared to unmodified Se NPs, the PCP-Se NPs exhibited low Se release (8.83 ± 0.73%) after simulated gastrointestinal digestion, and they had excellent storage stability and salt ion stability. PCP-Se NPs exhibited potent antioxidant activity manifested by the effective scavenging of DDPH and ABTS radicals. PCP-Se NPs were efficiently internalized by RAW264.7 cells and released into the cytoplasm by a lysosomal escape mechanism, thereby effectively reducing intracellular inflammatory factor levels (the levels of MPO, NO, iNOS, TNF-α, IL-1β, and IL-10 in the PCP-Se NPs treatment group were 0.38 ± 0.013-fold, 0.26 ± 0.02-fold, 0.36 ± 0.02-fold, 0.57 ± 0.03-fold, 0.35 ± 0.02-fold, and 2.07 ± 0.16-fold that of the LPS group, respectively), alleviating oxidative stress (the levels of CAT, SOD, GSH, and MDA in the PCP-Se NP-treated group were 2.48 ± 0.02-fold, 1.91 ± 0.11-fold, 3.16 ± 0.28-fold, and 0.46 ± 0.03-fold that of the LPS group, respectively), and maintaining mitochondrial membrane potential stability. This study provides a basis and reference for improving the stability of Se NPs and developing novel selenium-enriched dietary supplements.

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