槲皮素（QUE）是一种植物化合物，存在于各种植物食品中，已被证明在体内具有各种生理活性，尽管其活性发生的生物位点和转运机制尚未完全阐明。在本研究中，发现QUE进入HT-29人类结肠腺癌细胞后会产生自发释放的细胞外囊泡（EVs），并在其中嵌入QUE。此外，QUE嵌入的EVs也被检测到QUE服用的斯普拉格-道利大鼠的血清中。有趣的是，QUE封装的EVs（EV-QUE）在RAW264.7巨噬细胞中的细胞摄取速率明显高于游离的QUE。此外，与游离的QUE相比，EV-QUE在较低浓度下抑制了脂多糖（LPS）诱导的一氧化氮。本研究结果表明，QUE可能被嵌入到胃肠道中的EVs中，然后被吸收并进入血液展现生物活性。 © 2023 Wiley-VCH GmbH.

Quercetin (QUE), a phytochemical found in various plant foods, has been shown to have a variety of physiological activities in vivo, though biological sites where it has activities and the mechanisms of transport have not been fully elucidated.In the present study, intracellular uptake of QUE into HT-29 human colon adenocarcinoma cells is found to result in spontaneous release of extracellular vesicles (EVs), which are subsequently embedded with QUE. In addition, QUE-embedded EVs are detected in serum of QUE-administered Sprague-Dawley rats. Interestingly, the rate of cellular uptake of QUE-encapsulated EVs (EV-QUE) into RAW264.7 macrophages is markedly higher than that of free QUE. Moreover, EV-QUE suppresses lipopolysaccharide (LPS)-induced nitric oxide at a lower concentration than free QUE.The present findings suggest that QUE may be embedded in EVs in the gastrointestinal tract, then become absorbed and enter the bloodstream to exhibit biological activities.© 2023 Wiley-VCH GmbH.