State Key Laboratory of Food Science and Technology , Jiangnan University , Wuxi 214122 , China.
National Engineering Laboratory for Cereal Fermentation Technology , Jiangnan University , Wuxi 214122 , China.
J Agric Food Chem. 2020 Feb 26;68(8):2347-2356. doi: 10.1021/acs.jafc.9b06576. Epub 2020 Feb 17.
Avenanthramides (AVNs) are a unique kind of polyphenols that were only detected in the oats and have been demonstrated to exhibit strong antioxidant activities but low bioavailability. The purpose of the present research was to evaluate the absorption rates and mechanisms of AVNs (AVN 2c, AVN 2f, and AVN 2p) using a human colon adenocarcinoma cell line (Caco-2) cell model and clarify the influence of the absorption process on the antioxidant capacities of AVNs. Furthermore, the absorption rates and antioxidant activities of ferulic acid and caffeic acid were compared with those of AVNs. Results showed that the apparent absorption rates () of AVN 2c, AVN 2f, and AVN 2p were 0.65 ± 0.05 × 10, 1.18 ± 0.16 × 10, and 1.44 ± 0.09 × 10 cm/s, respectively, which were significantly lower than those of caffeic acid (3.76 ± 0.31 × 10 cm/s) and ferulic acid (1.69 ± 0.13 × 10 cm/s). Moreover, the metabolites (caffeic acid, ferulic acid, and AVN 2f) of AVNs after absorption were detected and quantified by high-performance liquid chromatography-mass spectrometry. Before absorption, although the antioxidant capacities of AVNs were significantly stronger than those of ferulic acid and caffeic acid, there was an opposite result after absorption. In addition, AVNs transported the Caco-2 monolayer by paracellular diffusion and were affected by monoamine oxidase and efflux transporters (P-gp, MRP2) during absorption. The co-administration of quercetin could significantly improve the absorption rates of AVNs.
燕麦蒽酰胺（AVNs）是一种独特的多酚，仅在燕麦中被检测到，具有很强的抗氧化活性，但生物利用度低。本研究旨在使用人结肠腺癌细胞系（Caco-2）细胞模型评估 AVNs（AVN 2c、AVN 2f 和 AVN 2p）的吸收速率和机制，并阐明吸收过程对 AVNs 抗氧化能力的影响。此外，还比较了阿魏酸和咖啡酸的吸收速率和抗氧化活性与 AVNs 的吸收速率和抗氧化活性。结果表明，AVN 2c、AVN 2f 和 AVN 2p 的表观吸收速率（）分别为 0.65 ± 0.05×10、1.18 ± 0.16×10 和 1.44 ± 0.09×10 cm/s，明显低于咖啡酸（3.76 ± 0.31×10 cm/s）和阿魏酸（1.69 ± 0.13×10 cm/s）。此外，通过高效液相色谱-质谱法检测和定量了吸收后 AVNs 的代谢产物（咖啡酸、阿魏酸和 AVN 2f）。吸收前，虽然 AVNs 的抗氧化能力明显强于阿魏酸和咖啡酸，但吸收后结果相反。此外，AVNs 通过细胞旁扩散转运 Caco-2 单层，并在吸收过程中受单胺氧化酶和外排转运体（P-gp、MRP2）的影响。槲皮素的共同给药可显著提高 AVNs 的吸收速率。
