Dzikaite Vijole, Holmström Petra, Stål Per, Eckes Kristina, Hagen Karin, Eggertsen Gösta, Gåfvels Mats, Melefors Ojar, Hultcrantz Rolf
Department of Gastroenterology and Hepatology, Karolinska Institutet, Karolinska University Hospital Solna, 171 76 Stockholm, Sweden.
J Hepatol. 2006 Mar;44(3):544-51. doi: 10.1016/j.jhep.2005.07.028. Epub 2005 Aug 22.
BACKGROUND/AIMS: To study the effect of iron and proinflammatory cytokines on the expression of HAMP and other iron regulatory genes in primary rat hepatocytes.
Primary hepatocytes from rats fed a control or iron-enriched diet were plated on extracellular matrix and incubated with inflammatory stimuli in the presence or absence of serum. Cells were also incubated with desferrioxamine or ferric ammonium citrate. mRNA levels were determined by Real-Time PCR.
Hepatocytes from control rats increased their HAMP expression during culturing, whereas the opposite was seen in hepatocytes from carbonyl-iron loaded animals. In the presence of serum, tumor necrosis factor-alpha, lipopolysaccharide and interleukin-6 increased HAMP expression in hepatocytes from both control and iron-loaded rats. Under serum-free conditions only tumor necrosis factor-alpha increased HAMP mRNA levels. Desferrioxamine and ferric ammonium citrate decreased HAMP gene expression. Tumor necrosis factor-alpha significantly increased mRNA levels of TfR2 and decreased those of DMT1 and IREG1.
HAMP expression differs in cultured as compared with freshly isolated hepatocytes, and decreases in iron-loaded hepatocytes in serum free-media, suggesting that additional serum factors influence HAMP expression. Tumor necrosis factor-alpha regulates the mRNA levels of HAMP, IREG1, DMT1 and TfR2 in cultured hepatocytes from both iron-loaded and control animals.
背景/目的：研究铁和促炎细胞因子对原代大鼠肝细胞中HAMP及其他铁调节基因表达的影响。
将喂食对照饮食或高铁饮食的大鼠的原代肝细胞接种于细胞外基质上，在有或无血清的情况下用炎性刺激物进行孵育。细胞还用去铁胺或柠檬酸铁铵进行孵育。通过实时定量PCR测定mRNA水平。
对照大鼠的肝细胞在培养过程中HAMP表达增加，而羰基铁负荷动物的肝细胞则出现相反情况。在有血清的情况下，肿瘤坏死因子-α、脂多糖和白细胞介素-6可增加对照大鼠和铁负荷大鼠肝细胞中的HAMP表达。在无血清条件下，只有肿瘤坏死因子-α能增加HAMP mRNA水平。去铁胺和柠檬酸铁铵可降低HAMP基因表达。肿瘤坏死因子-α显著增加TfR2的mRNA水平，并降低DMT1和IREG1的mRNA水平。
与新鲜分离的肝细胞相比，培养的肝细胞中HAMP表达有所不同，且在无血清培养基中铁负荷肝细胞中HAMP表达降低，提示其他血清因子会影响HAMP表达。肿瘤坏死因子-α可调节铁负荷大鼠和对照大鼠培养肝细胞中HAMP、IREG1、DMT1和TfR2的mRNA水平。
