de Souza Gonçalves Bruno, de Moura Valadares Jéssica M, Alves Silmara L G, Silva Simone C, Rangel Luciana P, Cortes Vanessa F, Villar José A F P, Barbosa Leandro A, de Lima Santos Hérica
Laboratório de Bioquímica Celular, Universidade Federal de São João del Rei, Divinópolis, Minas Gerais, Brazil.
Laboratório de Síntese Orgânica e Nanoestruturas, Universidade Federal de São João del Rei, Divinópolis, Minas Gerais, Brazil.
J Cell Biochem. 2019 Oct;120(10):17108-17122. doi: 10.1002/jcb.28971. Epub 2019 Jul 16.
Recently, cardiotonic steroids (CTS) have been shown to lead to the activation of Na,K-ATPase at low concentrations in brain, promoting neuroprotection against ischemia. We report here the results of the use of digoxin and its semisynthetic derivatives BD-14, BD-15, and BD-16 against partial chemical ischemic induction followed by reperfusion in murine neuroblastoma cells neuro-2a (N2a). For chemical ischemic induction, sodium azide (5 mM) was used for 5 hours, and then reperfusion was induced for 24 hours. Na,K-ATPase activity and protein levels were analyzed in membrane preparation of N2a cells pretreated with the compounds (150 nM), in the controls and in induced chemical ischemia. In the Na,K-ATPase activity and protein levels assays, the steroids digoxin and BD-15 demonstrated a capacity to modulate the activity of the enzyme directly, increasing its levels of expression and activity. Oxidative parameters, such as superoxide dismutase (SOD) activity, lipid peroxidation (thiobarbituric acid reactive substance), glutathione peroxidase (GPx), glutathione (GSH) levels, hydrogen peroxide content, and the amount of free radicals (reactive oxygen species) during induced chemical ischemia were also evaluated. Regarding the redox state, lipid peroxidation, hydrogen peroxide content, and GPx activity, we have observed an increase in the chemical ischemic group, and a reduction in the groups treated with CTS. SOD activity increased in all treated groups when compared to control and GSH levels decreased when treated with sodium azide and did not change with CTS treatments. Regarding the lipid profile, we saw a decrease in the content of phospholipids and cholesterol in the chemical ischemic group, and an increase in the groups treated with CTS. In conclusion, the compounds used in this study demonstrate promising results, since they appear to promote neuroprotection in cells exposed to chemical ischemia.
最近研究表明，强心甾类化合物（CTS）在低浓度时可激活大脑中的钠钾ATP酶，促进对缺血的神经保护作用。我们在此报告地高辛及其半合成衍生物BD - 14、BD - 15和BD - 16用于小鼠神经母细胞瘤细胞Neuro - 2a（N2a）部分化学性缺血诱导后再灌注的结果。对于化学性缺血诱导，使用叠氮化钠（5 mM）处理5小时，然后诱导再灌注24小时。分析了用化合物（150 nM）预处理的N2a细胞膜制剂、对照组和诱导化学性缺血组中的钠钾ATP酶活性和蛋白质水平。在钠钾ATP酶活性和蛋白质水平测定中，甾体类药物地高辛和BD - 15显示出直接调节该酶活性的能力，增加其表达水平和活性。还评估了诱导化学性缺血期间的氧化参数，如超氧化物歧化酶（SOD）活性、脂质过氧化（硫代巴比妥酸反应性物质）、谷胱甘肽过氧化物酶（GPx）、谷胱甘肽（GSH）水平、过氧化氢含量和自由基（活性氧）量。关于氧化还原状态、脂质过氧化、过氧化氢含量和GPx活性，我们观察到化学性缺血组增加，而CTS处理组减少。与对照组相比，所有处理组的SOD活性均增加，用叠氮化钠处理时GSH水平降低，而CTS处理时GSH水平不变。关于脂质谱，我们发现化学性缺血组的磷脂和胆固醇含量降低，而CTS处理组增加。总之，本研究中使用的化合物显示出有前景的结果，因为它们似乎能促进暴露于化学性缺血的细胞中的神经保护作用。
