College of Food Science and Engineering , Ocean University of China , 5 Yushan Road , Qingdao , Shandong Province 266003 , China.
J Agric Food Chem. 2018 Aug 1;66(30):8026-8035. doi: 10.1021/acs.jafc.8b03381. Epub 2018 Jul 19.
Polyphosphates are one of the active compounds from probiotics to maintain gut health. The current research extracted and purified intact biogenic polyphosphate nanoparticles (BPNPs) from Synechococcus sp. PCC 7002 cells. BPNPs were near-spherical anionic particles (56.9 ± 15.1 nm) mainly composed of calcium and magnesium salt of polyphosphate and were colloidally stable at near-neutral and alkaline pH. BPNPs survived gastrointestinal digestion in mice and could be absorbed and transported by polarized Caco-2 cell monolayers. They dose-dependently increased the tightness of intercellular tight junction and the expression of claudin-4, occludin, zonula occludens-1, and heat shock protein 27 in Caco-2 cell monolayers. BPNPs also effectively attenuated HO-induced cell death, plasma membrane impairment, and intracellular superoxide production in NCM460 cells. In addition, they conferred resistance to HO-induced barrier disruption in freshly excised mouse small intestine. Our results suggest that BPNPs are a promising postbiotic nanomaterial with potential applications in gut health maintenance.
多聚磷酸盐是益生菌维持肠道健康的活性化合物之一。本研究从聚球藻 PCC 7002 细胞中提取并纯化了完整的生物源性多聚磷酸盐纳米颗粒（BPNPs）。BPNPs 呈近球形阴离子颗粒（56.9±15.1nm），主要由多聚磷酸盐的钙盐和镁盐组成，在近中性和碱性 pH 下具有胶体稳定性。BPNPs 能在小鼠的胃肠道消化中存活，并能被极化的 Caco-2 细胞单层吸收和转运。它们能剂量依赖性地增加细胞间紧密连接的紧密性，并增加 Caco-2 细胞单层中 Claudin-4、Occludin、 zonula occludens-1 和热休克蛋白 27 的表达。BPNPs 还能有效减轻 NCM460 细胞中 HO 诱导的细胞死亡、质膜损伤和细胞内超氧产生。此外，它们还能赋予 HO 诱导的新鲜分离的小鼠小肠屏障破坏的抗性。我们的研究结果表明，BPNPs 是一种很有前途的后生元纳米材料，具有维持肠道健康的潜在应用前景。
