Caffeine and CSC, adenosine A2A antagonists, offer neuroprotection against 6-OHDA-induced neurotoxicity in rat mesencephalic cells
Caffeine and CSC, adenosine A2A antagonists, offer neuroprotection against 6-OHDA-induced neurotoxicity in rat mesencephalic cells
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DOI：
10.1016/j.neuint.2009.09.001
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发表时间：
2010-01-01
影响因子：
4.2
通讯作者：
de Barros Viana, Glauce Socorro
中科院分区：
文献类型：
--
作者：
Nobre, Helio Vitoriano, Jr.;de Andrade Cunha, Geanne Matos;de Barros Viana, Glauce Socorro
本实验研究了A（2A）受体拮抗剂咖啡因（CAF）和8-（3-氯苯乙烯基）-咖啡因（CSc）对6-羟基多巴胺（6-OHDA）诱导的大鼠中脑细胞毒性的保护作用。两种药物在暴露于6-OHDA后显著增加了活细胞的数量，如通过MTT测定所测量的。虽然6-OHDA使细胞中的亚硝酸盐水平急剧增加，但在CAF或CSC后其浓度接近正常，表明这两种药物都能阻断6-OHDA诱导的氧化应激，从而导致自由基的产生。用CAF或CSC处理细胞后，观察到6-OHDA诱导的脂质过氧化反应（被认为是DNA损伤的主要来源）被完全阻断。6-OHDA减少了正常细胞的数量，同时增加了凋亡细胞的数量。在CAF加6-OHDA组中，与单独用6-OHDA处理的组相比，观察到活细胞数量的显著恢复和凋亡细胞数量的减少。在6-OHDA存在下，细胞暴露于CSC后观察到类似的效果。出乎意料的是，虽然在细胞暴露于CAF加6-OHDA后观察到显著较低数量的活化小胶质细胞，但在相同条件下细胞暴露于CSC后情况并非如此。而CAF降低反应性星形胶质细胞的百分比增加6-OHDA，CSC没有效果。这些药物的影响也进行了检查释放髓过氧化物酶（MPO），炎症标志物，和乳酸脱氢酶（LDH），细胞毒性的标志物，在人类中性粒细胞，在体外。CSC和CAF（01，1和10 μ g/ml）产生抑制MPO释放PMA刺激的细胞，从45%到83%。此外，CSC和CAF（5、50和100 μ g/ml）在使用的浓度范围内未显示任何细胞毒性，如通过LDH测定所确定的。总之，我们的研究结果表明，咖啡因或CSC对暴露于6-OHDA的大鼠中脑细胞具有强烈的神经保护作用。此外，CSC和咖啡因的作用，抑制MPO以及LDH的释放，将有助于其在治疗神经退行性疾病，包括DP的可能的好处。这些作用部分归因于这些A2 A拮抗剂降低细胞自由基产生和氧化应激的能力，这是6-OHDA诱导的细胞毒性的主要成分。(C)2009年爱思唯尔有限公司保留所有战斗。
In this study, the cytoprotective effects of caffeine (CAF) and 8-(3-chlorostyryl)-caffeine (CSc), A(2A) receptor antagonists, were tested against 6-OHDA-induced cytotoxicity, in rat mesencephalic cells. Both drugs significantly increased the number of viable cells, after their exposure to 6-OHDA, as measured by the MTT assay. While nitrite levels in the cells were drastically increased by 6-OHDA, their concentrations were brought toward normality after CAF or CSC, indicating that both drugs block 6-OHDA-induced oxidative stress which leads to free radicals generation. A complete blockade of 6-OHDA-induced lipid peroxidation, considered as a major source of DNA damage, was observed after cells treatment with CAF or CSC. 6-OHDA decreased the number of normal cells while increasing the number of apoptotic cells. In the CAF plus 6-OHDA group, a significant recover in the number of viable cells and a decrease in the number of apoptotic cells were seen, as compared to the group treated with 6-OHDA alone. A similar effect was observed after cells exposure to CSC in the presence of 6-OHDA. Unexpectedly, while a significant lower number of activated microglia was observed after cells exposure to CAF plus 6-OHDA, this was not the case after cells exposure to CSC under the same conditions. While CAF lowered the percentage of reactive astrocytes increased by 6-OHDA, CSC presented no effect. The effects of these drugs were also examined on the releases of myeloperoxidase (MPO), an inflammatory marker, and lactate dehydrogenase (LDH), a marker for cytotoxicity, in human neutrophils, in vitro. CSC and CAF (01, 1 and 10 mu g/ml) produced inhibitions of the MPO release from PMA-stimulated cells, ranging from 45 to 83%. In addition, CSC and CAF (5, 50 and 100 mu g/ml) did not show any cytotoxicity in the range of concentrations used, as determined by the LDH assay. All together, our results showed a strong neuroptrotection afforded by caffeine or CSC, on rat mesencephalic cells exposed to 6-OHDA. Furthermore, CSC and caffeine actions, inhibiting MPO as well as LDH releases, would contribute to their possible benefit in the treatment of neurodegenerative diseases, including DP. These effects are partially due to the ability of these A2A antagonists to decrease the cells free radicals production and oxidative stress, that are major components of 6-OHDA-induced cytotoxicity. (C) 2009 Elsevier Ltd. All Fights reserved.