Phage display identification of age-associated TNFalpha-mediated cardiac oxidative induction.
Phage display identification of age-associated TNFalpha-mediated cardiac oxidative induction.
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DOI：
10.1152/physiolgenomics.00161.2003
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发表时间：
2004-08
影响因子：
4.6
通讯作者：
J. Edelberg;A. Wong;Jacquelyne M. Holm;Munira Xaymardan;I. Duignan;Andrew Chin;J. Kizer;Dongqing Cai
中科院分区：
文献类型：
--
作者：
J. Edelberg;A. Wong;Jacquelyne M. Holm;Munira Xaymardan;I. Duignan;Andrew Chin;J. Kizer;Dongqing Cai
心脏中肿瘤坏死因子-α（TNF α）的作用与受损的心脏保护通路和增强的凋亡诱导相关的改变可能导致老年人心血管病变的严重程度增加。为了鉴定介导这些衰老啮齿动物心脏微血管变化的分子事件，研究了体内噬菌体展示环肽心脏生物淘选的生物化学性质。单个氨基酸位置的分析显示，与年轻对照相比，在噬菌体归巢到老年心脏中，肽基序的中心（氨基酸位置4）具有显著更高的芳香族氨基酸侧链频率（18月龄，11%对3月龄，3%，P < 0.05）。这个子集的噬菌体基序揭示了与年龄相关的同源性与氧化还原酶（同源性：18个月，7/7; 3个月，0/2），这表明这些酶的底物和/或结合位点的增加，在老化的心脏。对氧化还原酶底物4-羟基-2-壬烯醛（HNE）（一种心脏毒性脂质过氧化产物）的免疫染色显示，与年轻对照组（3个月）相比，PBS处理的老年小鼠（18个月）心脏中的HNE（+）细胞密度高两倍（18个月，3.2 +/- 2.8 vs. 3个月，1.0 +/- 0.9个细胞/HPF，P < 0.05）。此外，心内注射TNF α导致老年心脏中HNE染色显著增加（18个月，16.9 +/- 13.8 vs. 3个月，9.1 +/- 6.0个细胞/HPF，P < 0.05）。总体而言，这些研究表明，TNF α介导的通路中的衰老相关改变，诱导反应性氧化物质和血管表面结合位点的变化，可能在机制上导致衰老心脏的心血管病理学增加。
Age-associated alterations in the actions of tumor necrosis factor-alpha (TNFalpha) in the heart with impaired cardioprotective pathways and enhanced apoptotic induction may contribute to the increased severity of cardiovascular pathology in older persons. To identify the molecular events mediating these changes in the microvasculature of the aging rodent heart, the biochemical properties of in vivo phage-display cyclic peptide cardiac biopanning were studied. Analysis of individual amino acid positions revealed that the center of the peptide motif (amino acid position 4) had a significantly higher frequency of aromatic amino acid side chains in phage homing to the old hearts compared with young controls (18 mo old, 11% vs. 3 mo old, 3%, P < 0.05). This subset of phage motifs revealed an age-associated homology with oxidoreductase enzymes (homology: 18 mo, 7/7; 3 mo, 0/2), suggesting the substrates and/or binding sites of these enzymes are increased in the aging hearts. Immunostaining for the oxidoreductase substrate 4-hydroxy-2-nonenal (HNE), a cardiotoxic lipid peroxidation product, demonstrated a twofold higher density of HNE(+) cells in PBS-treated hearts of old mice (18 mo) compared with young controls (3 mo) (18 mo, 3.2 +/- 2.8 vs. 3 mo, 1.0 +/- 0.9 cells/HPF, P < 0.05). Moreover, intracardiac injection of TNFalpha resulted in a significantly greater increase in HNE staining in the old hearts (18 mo, 16.9 +/- 13.8 vs. 3 mo, 9.1 +/- 6.0 cells/HPF, P < 0.05). Overall, these studies demonstrate that aging-associated alterations in TNFalpha-mediated pathways with induction of reactive oxidative species and changes in vascular surface binding sites may contribute mechanistically to the increased cardiovascular pathology of the aging heart.