Differential expression of TRPM2 and TRPV4 channels and their potential role in oxidative stress-induced cell death in organotypic hippocampal culture
Differential expression of TRPM2 and TRPV4 channels and their potential role in oxidative stress-induced cell death in organotypic hippocampal culture
复制标题
DOI：
10.1016/j.neuro.2010.01.001
复制
发表时间：
2010-03-01
期刊：
影响因子：
3.4
通讯作者：
Lipski, Janusz
中科院分区：
文献类型：
--
作者：
Bai, Ji-Zhong;Lipski, Janusz
TRPM 2和TPPV 4通道是TRP通道家族的两个成员，已知在脑中广泛表达，但其确切表达模式和功能尚不清楚。由于它们的高Ca 2+渗透性和通过活性氧（TRPM 2）或细胞肿胀、低pH和高温（TRPV 4）的门控，它们可能参与与各种脑病理学相关的细胞损伤。本研究的目的是研究这些通道的表达及其在器官型海马切片培养中氧化应激诱导的细胞损伤中的潜在作用，该模型保留了神经元和星形胶质细胞之间复杂的相互作用。RT-PCR和蛋白质印迹法证实了通道的表达，而免疫细胞化学证实了TRPM 2在CA 1-CA 3锥体神经元中，TRPV 4在星形胶质细胞中。氧化应激诱导的外源性应用H2 O2（600 μ M）引起的优先损害的锥体神经元，而氧化应激引起的巯基琥珀酸酯（MCS; 400 μ M）或丁硫醚亚砜（BSO; 4 μ M）主要损害星形胶质细胞，碘化丙啶荧光。抗氧化剂（Trolox 500 μ M; MitoE 2 μ M）减少神经元和星形胶质细胞死亡。TRPV 4通道阻断剂（Gd 3 + 500 μ M;钌红1 μ M）增加了MCS或BSO处理后星形胶质细胞的活力，与这些通道的表达模式一致。TRPM 2通道阻断剂克霉唑（20 μ M），N-（p-amylcinnomoyl）邻氨基苯甲酸（ACA，25 μ M）或氟灭酸（FFA，200 μ M）未能保护锥体神经元免受外源性H2 O2引起的损伤，并增加了MCS和BSO引起的这些神经元的损伤。应激敏感性TRPM 2和TRPV 4通道在海马神经元和星形胶质细胞中的差异表达表明这些通道在氧化应激诱导的细胞损伤中的特异性参与，这些通道对不同形式的氧化应激表现出明显的差异。然而，由于TRPM 2通道阻断剂缺乏保护作用，TRPM 2通道激活和细胞死亡之间的确切关系仍有待确定。(C)2010年爱思唯尔公司All rights reserved.
TRPM2 and TPPV4 channels, two members of TRP channel family, are known to be widely expressed in the brain but their exact expression pattern and function are not well understood. Due to their high Ca2+ permeability and gating by reactive oxygen species (TRPM2), or cell swelling, low pH and high temperature (TRPV4), they are likely to be involved in cell damage associated with various brain pathologies. The aim of this study was to investigate the expression of these channels and their potential role in oxidative stress-induced cell damage in organotypic hippocampal slice cultures, a model that retains the complex interaction between neurons and astrocytes. Channel expression was confirmed with RT-PCR and western blotting, while immunocytochemistry demonstrated TRPM2 in CA1-CA3 pyramidal neurons and TRPV4 in astrocytes. Oxidative stress induced by exogenous application of H2O2 (600 mu M) caused preferential damage of pyramidal neurons, while oxidative stress evoked with mercaptosuccinate (MCS; 400 mu M) or buthionine sulfoximine (BSO; 4 mu M) mainly damaged astrocytes, as identified by propidium iodide fluorescence. Antioxidants (Trolox 500 mu M; MitoE 2 mu M) reduced both neuronal and astrocytic cell death. Blockers of TRPV4 channels (Gd3+ 500 mu M; Ruthenium red 1 mu M) increased the viability of astrocytes following MCS or BSO treatments, consistent with the expression pattern of these channels. Blockers of TRPM2 channels clotrimazole (20 mu M), N-(p-amylcinnomoyl)anthranilic acid (ACA, 25 mu M) or flufenamic acid (FFA, 200 mu M) failed to protect pyramidal neurons from damage caused by exogenous H2O2, and increased damage of these neurons caused by MCS and BSO. The differential expression of stress-sensitive TRPM2 and TRPV4 channels in hippocampal neurons and astrocytes that show distinct differences in vulnerability to different forms of oxidative stress suggests the specific involvement of these channels in oxidative stress-induced cell damage. However, the exact relationship between TRPM2 channel activation and cell death still remains to be determined due to the lack of protective effects of TRPM2 channel blockers. (C) 2010 Elsevier Inc. All rights reserved.