维生素D调控巨噬细胞极化对肝细胞脂质代谢的作用及机制  

EFFECT OF VITAMIN D ON LIPID METABOLISM BY MODULATING MACROPHAGE POLARIZATION IN HEPATOCYTES

作　　者：罗雯静 董显文 赵巧素 郭雯莹 柳惠未 叶桦[1] LUO Wen-jing;DONG Xian-wen;ZHAO Qiao-su;GUO Wen-ying;LIU Hui-wei;YE Hua(Department of Gastroenterology,The Affiliated Li huili Hospital,Ningbo University,Ningbo 315000,China)

机构地区：[1]宁波大学附属李惠利医院消化内科,宁波315000

出　　处：《营养学报》2024年第2期139-145,共7页Acta Nutrimenta Sinica

基　　金：宁波市自然科学基金(No.202003N4234);浙江省医药卫生科技计划(No.2024KY1477)。

摘　　要：目的探讨维生素D(vitaminD,VD)调控脂肪酸诱导的巨噬细胞M1-M2极化表型转变对肝细胞脂质代谢的直接作用及机制。方法体外饱和脂肪酸孵育培养小鼠巨噬细胞RAW264.7并予活性VD-1,25(OH)2D3补充干预,制备相应的条件培养液体外培养小鼠肝细胞AML12。Real-time PCR检测巨噬细胞M1/M2极化基因表达水平,Real-time PCR、Westernblot分别检测巨噬细胞VD受体(VDreceptor,VDR)/过氧化物酶体增殖物激活受体γ(peroxisome proliferator-activated receptor gamma,PPARγ)基因、蛋白表达水平;油红O染色观察肝细胞内脂质沉积表现,Real-time PCR、Western blot分别检测肝细胞脂质合成和分解代谢相关酶类基因、蛋白表达水平。结果体外饱和脂肪酸作用下,与VD对照组相较,VD补充组巨噬细胞M1极化基因诱生型一氧化氮合酶2(inducible nitric oxide synthase 2,iNOS2)、肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)和白细胞介素-6(interleukin-6,IL-6)及M2极化基因白细胞介素-10(interleukin-10,IL-10)mRNA表达水平均明显降低,巨噬细胞VDR/PPARγmRNA和蛋白表达水平均明显降低。体外饱和脂肪酸作用的巨噬细胞条件培养液孵育肝细胞,与VD对照组相较,VD补充组肝细胞脂肪变性明显减少,肝细胞脂质合成代谢酶[固醇调节元件结合蛋白1C(sterol-regulatoryelementbindingprotein1C,SREBP1C)、脂肪酸合酶(fattyacidsynthase,FASN)]mRNA和蛋白表达水平均明显降低,脂质分解代谢酶肉碱棕榈酰转移酶1A(carnitine palmitoyltransferase 1A,CPT1A)mRNA和蛋白表达水平明显降低。结论补充VD介导VDR/PPARγ通路逆转脂肪酸诱导的巨噬细胞极化表型直接影响肝细胞脂质代谢水平并改善肝细胞脂肪变性。Objective To investigate the effect of vitamin D(VD)on lipid metabolism by modulating fatty-acid induced macrophage M1-M2 polarization in hepatocytes.Methods Saturated fatty acid treated RAW264.7 macrophages were cultured in DMEM with 1,25(OH)2D3,and the conditioned medium(CM)were prepared.Then,AML12 hepatocytes were cultured in CM for 24 h.The M1/M2 polarization phenotype markers of macrophages were detected by RT-PCR.The mRNA and protein expressions of VDR and PPARγof macrophages were detected by real-time PCR and Western blot,respectively.Lipid deposition in hepatocytes was examined by oil red O staining.The mRNA and protein expressions of lipometabolic enzymes of hepatocytes were detected by RT-PCR and Western blot,respectively.Results Compared to palmitic acid(PA)treated VD control group,the mRNA expressions of M1 phenotype markers,including iNOS2,TNFαand IL-6,and M2phenotype marker IL-10,as well as the mRNA and protein expressions of VDR and PPARγof macrophages in PA plus VD treated group were significantly decreased.Hepatocyte steatosis was obviously alleviated in the CM-PA plus VD treated group compared to the CM-PA plus VD control group.The mRNA and protein expressions of SREBP1C and FASN,as well as CPT1A of hepatocytes were significantly decreased in CM-PA plus VD treated group compared to the CM-PA plus VD control group.Conclusion VD supplementation improves lipid metabolism by reversing fatty-acid induced macrophage polarization through VDR/PPARγpathway in hepatocytes.

关 键 词：维生素D 巨噬细胞 极化 肝细胞 脂质代谢 

分 类 号：R151.2[医药卫生—营养与食品卫生学]