Ji Wen-Na, Yan Mei-Qiu, Su Jie, Yu Jing-Jing, Chen Su-Hong, Lyu Gui-Yuan, Chen Jian-Zhen
Zhejiang Chinese Medical University Hangzhou 310053, China.
Zhejiang University of Technology Hangzhou 310014, China.
Zhongguo Zhong Yao Za Zhi. 2022 May;47(9):2525-2532. doi: 10.19540/j.cnki.cjcmm.20211223.703.
Dendrobium officinale can serve as Chinese medicinal material effective in nourishing yin, clearing heat, and producing fluid, and is used to treat throat diseases, but its active substances and mechanism are not clear. To clarify the active fraction and underlying mechanism of D. officinale against chronic pharyngitis(CP), the present study induced a CP model in rats by pepper water combined with low-concentration ammonia, and crude polysaccharides of D. officinale(DOP), non-polysaccharides of D. officinale(DON), and total extract of D. officinale(DOT)(0.33 g·kg(-1), calculated according to the crude drug) were administered by gavage for six weeks. The changes in oral secretions and pharyngeal conditions of rats with CP were observed and rated. The hematological indicators were determined by an automatic hematology analyzer. The serum levels of pro-inflammatory factors, such as tumor necrosis factor-alpha(TNF-α), interleukin 1β(IL-1β), and interleukin 6(IL-6), and T-lymphocyte cytokines, including interferon γ(IFN-γ), interleukin 4(IL-4), interleukin 17(IL-17), and transforming growth factor β1(TGF-β1) were detected by the enzyme-linked immunosorbent assay(ELISA). The proportions of CD3+, CD4+, and CD8+cells in peripheral blood T lymphocyte subsets were determined by the flow cytometry. The histomorphological changes of the pharynx were observed by hematoxylin-eosin(HE) staining. The protein expression of nuclear factor-κB P65(NF-κB P65), cyclooxygenase-2(COX-2), F4/80, and monocyte chemoattractant protein-1(MCP-1) in the pharynx were detected by immunohistochemistry and Western blot. The results showed that DOP and DON could significantly relieve pharyngeal lesions, reduce white blood cells(WBC) and lymphocytes(LYMP), decrease the levels of pro-inflammatory factors TNF-α, IL-6, and IL-1β, and inhibit the protein expression of NF-κB P65, COX-2, F4/80, and MCP-1 in the pharynx. DOP was superior in reducing oral secretions and serum IL-17 level and inferior in increasing CD4+/CD8+ratio to DON. It is suggested that both polysaccharides and non-polysaccharides of D. officinale have anti-PC effects and the anti-inflammatory mechanism may be related to the regulation of T lymphocyte distribution and inhibition of the inflammatory signaling pathways mediated by NF-κB P65. The anti-inflammatory effect of DOP may be related to the regulation of Th17/Treg balance, while that of DON may be related to the regulation of the Th/Tc ratio.
铁皮石斛可作为一种有效的中药材，具有滋阴清热、生津止渴的功效，常用于治疗咽喉疾病，但其活性成分及作用机制尚不明确。为阐明铁皮石斛抗慢性咽炎（CP）的活性部位及潜在机制，本研究采用辣椒水联合低浓度氨水诱导大鼠建立CP模型，并通过灌胃给予铁皮石斛粗多糖（DOP）、非多糖（DON）和总提取物（DOT）（0.33 g·kg⁻¹，按生药量计算），持续六周。观察并评估CP大鼠口腔分泌物及咽部状况的变化。使用自动血液分析仪测定血液学指标。通过酶联免疫吸附测定（ELISA）检测血清中促炎因子如肿瘤坏死因子-α（TNF-α）、白细胞介素1β（IL-1β）和白细胞介素6（IL-6）以及T淋巴细胞细胞因子包括干扰素γ（IFN-γ）、白细胞介素4（IL-4）、白细胞介素17（IL-17）和转化生长因子β1（TGF-β1）的水平。采用流式细胞术测定外周血T淋巴细胞亚群中CD3⁺、CD4⁺和CD8⁺细胞的比例。通过苏木精-伊红（HE）染色观察咽部的组织形态学变化。采用免疫组织化学和蛋白质印迹法检测咽部核因子-κB P65（NF-κB P65）、环氧化酶-2（COX-2）、F4/80和单核细胞趋化蛋白-1（MCP-1）的蛋白表达。结果表明，DOP和DON均可显著减轻咽部病变，降低白细胞（WBC）和淋巴细胞（LYMP）数量，降低促炎因子TNF-α、IL-6和IL-1β的水平，并抑制咽部NF-κB P65、COX-2、F4/80和MCP-1的蛋白表达。在减少口腔分泌物和血清IL-17水平方面，DOP优于DON，但在提高CD4⁺/CD8⁺比值方面不如DON。提示铁皮石斛的多糖和非多糖均具有抗CP作用，其抗炎机制可能与调节T淋巴细胞分布及抑制NF-κB P65介导的炎症信号通路有关。DOP的抗炎作用可能与调节Th17/Treg平衡有关，而DON的抗炎作用可能与调节Th/Tc比值有关。
