Objective: To investigate the effect of Erchen Decoction on iron homeostasis in mice with nonalcoholic fatty liver disease (NAFLD) and its mechanism for regulating iron transport in spleen cells.
Methods: Thirty male C57BL/6J mice were given a high-fat diet for 12 weeks and randomized (n=6) at the 7th week for gavage (3 times a week) of drinking water (NAFLD model group), Erchen Decoction at low, medium and high doses (7.5, 15, and 30g/kg, respectively), or polyene phosphatidyl choline (PPC; 9.12 mg/kg), with another 6 mice with low-fat and low-sugar feeding as the control group. The active components of Erchen Decoction were determined by HPLC-MS. Lipid accumulation in the liver was evaluated by HE staining and Nile red staining. Prussian blue staining was used to observe iron content in the spleen. The iron ion content in the liver tissue was detected using a detection kit. The expressions of ferroportin1 (Fpn1), transferrin receptor (TfR), Steap3, HO-1, Ter-119, CD163 and CD68 were detected using Western blotting, immunohistochemistry and immunofluorescence staining.
Results: Medium- and high-dose Erchen Decoction partially reversed the increase of lipid accumulation in the liver of NAFLD mice and showed better lipid-lowering effect than PPC. The NAFLD mice showed significantly decreased iron ion content in the spleen with increased hepatic and serum iron contents (P < 0.05), decreased TfR protein expression (P < 0.05), and increased Fpn1 and Steap3 protein expressions (P < 0.05), and these changes were significantly improved by the drug interventions. Erchen Decoction also improved the function of CD163 macrophages in the spleen of NAFLD mice by up-regulating the expression of HO-1 (P < 0.05).
Conclusion: Erchen Decoction can alleviate high-fat diet-induced iron metabolism disorder by improving the iron ion transport ability of the spleen cells to delay the progression of NAFLD.
目的: 探讨二陈汤对非酒精性脂肪性肝病铁稳态的影响以及调控脾脏细胞铁离子转运能力的机制。
方法: 将36只雄性C57BL/6J小鼠，随机分为对照组、模型组、二陈汤低剂量组（7.5 g/kg）、二陈汤中剂量组（15 g/kg）、二陈汤高剂量组（30 g/kg）、多烯磷脂酰胆碱组（9.12 mg/kg），6只/组。对照组给予低脂低糖饮食，其余组给予高脂饲料饲养12周。药物组于第7周开始灌胃给药，其余组灌胃等体积饮用水，3次/周。采用HPLC-MS检测二陈汤的活性成份；HE染色和尼罗红染色评估肝脏脂质累积情况；普鲁士蓝染色观察脾脏铁含量；蛋白印迹法、免疫组织化学法以及免疫荧光染色法检测铁转运蛋白（Fpn1）、转铁蛋白受体（TfR）、前列腺六跨膜上皮抗原3（Steap3）、血红素加氧酶1（HO-1）、Ter-119、CD163和CD68的表达。
结果: 与对照组相比，模型组小鼠肝组织脂质累积显著增多，而中剂量和高剂量二陈汤组可部分逆转上述结果。与多烯磷脂酰胆碱组相比，中浓度和高浓度二陈汤组的降脂效果更佳。与对照组相比，模型组小鼠脾脏铁离子含量降低，血清铁离子浓度升高（P < 0.05），TfR蛋白表达降低（P < 0.05），Fpn1蛋白表达升高（P < 0.05）以及Steap3蛋白表达升高（P < 0.01）。药物组可降低血清铁离子水平（P < 0.01），上调脾组织铁离子含量，降低Fpn1和Steap3蛋白的表达（P < 0.01，P < 0.05），并上调脾脏TfR蛋白的表达（P < 0.05）。此外，与对照组相比，模型组脾脏HO-1表达显著降低（P < 0.01），而二陈汤通过上调HO-1的表达改善脾脏CD163巨噬细胞的功能（P < 0.05）。
结论: 二陈汤通过改善脾脏细胞铁离子转运能力抑制高脂饮食诱导的铁代谢紊乱，进而缓解NAFLD的进展。
Keywords: Erchen decoction; iron metabolism; non-alcoholic fatty liver disease; spleen.