Huang Guitao, Wang Zhineng, Wu Guangxu, Zhang Ruifen, Dong Lihong, Huang Fei, Zhang Mingwei, Su Dongxiao
School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P.R. China.
Sericultural & Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences/Key Laboratory of Functional Foods, Ministry of Agriculture and Rural Affairs/Guangdong Key Laboratory of Agricultural Products Processing, Guangzhou 510610, P.R. China.
J Agric Food Chem. 2021 Mar 24;69(11):3326-3339. doi: 10.1021/acs.jafc.0c07407. Epub 2021 Feb 3.
The preventive effect of lychee pulp phenolics (LPP) on dextran sulfate sodium (DSS)-induced colitis of mice and its underlying mechanisms were investigated in this research. LPP supplementation mitigated DSS-induced breakage of the gut barrier as evidenced by the increased tight junction proteins and the enhanced integrity of epithelial cells. Both LPP and 5-ASA treatments could downregulate the expressions of toll-like receptor 4 (TLR-4), NOD protein-like receptor 3 (NLRP3), and proinflammatory cytokines to normal levels. Notably, treatment with LPP at a dosage of 500 mg/kg/day effectively upregulated FFAR2 and FFAR3 expression and contents of short-chain fatty acids (SCFAs), suggesting the activation of the SCFA-FFAR (free fatty acid receptor) pathway. Consistently, the abundances of probiotic taxa and microbiota (, , , and ) associated with SCFA synthesis were elevated, whereas harmful bacteria ( and ) were suppressed. These data indicate that LPP ameliorates gut barrier damage, activates the microbiota-SCFA-FFAR signaling cascade, and suppresses the TLR4/NLRP3-NF-κB pathway, and therefore, LPP supplementation could be a promising way to protect the intestinal tract.
本研究探讨了荔枝果肉酚类物质（LPP）对葡聚糖硫酸钠（DSS）诱导的小鼠结肠炎的预防作用及其潜在机制。补充LPP减轻了DSS诱导的肠道屏障破坏，紧密连接蛋白增加和上皮细胞完整性增强证明了这一点。LPP和5-氨基水杨酸（5-ASA）处理均可将Toll样受体4（TLR-4）、NOD样受体蛋白3（NLRP3）和促炎细胞因子的表达下调至正常水平。值得注意的是，以500 mg/kg/天的剂量用LPP处理可有效上调游离脂肪酸受体2（FFAR2）和游离脂肪酸受体3（FFAR3）的表达以及短链脂肪酸（SCFA）的含量，表明SCFA-FFAR（游离脂肪酸受体）途径被激活。一致地，与SCFA合成相关的益生菌类群和微生物群（、、、和）的丰度升高，而有害细菌（和）受到抑制。这些数据表明，LPP可改善肠道屏障损伤，激活微生物群-SCFA-FFAR信号级联反应，并抑制TLR4/NLRP3-NF-κB途径，因此，补充LPP可能是保护肠道的一种有前途的方法。
