Division of Pharmacology, Department of Neuroscience, Reproductive Sciences and Dentistry, School of Medicine, Federico II University of Naples, Naples, Italy.
Department of Pharmacy, Federico II University of Naples, Naples, Italy.
Biomed Pharmacother. 2021 Nov;143:112111. doi: 10.1016/j.biopha.2021.112111. Epub 2021 Sep 1.
The Na/Ca exchanger NCX3 is an important regulator of sodium and calcium homeostasis in oligodendrocyte lineage. To date, no information is available on the effects resulting from prolonged exposure to NCX3 blockers and subsequent drug washout in oligodendroglia. Here, we investigated, by means of biochemical, morphological and functional analyses, the pharmacological effects of the NCX3 inhibitor, the 5-amino-N-butyl-2-(4-ethoxyphenoxy)-benzamide hydrochloride (BED), on NCXs expression and activity, as well as intracellular [Na] and [Ca] levels, during treatment and following drug washout both in human MO3.13 oligodendrocytes and rat primary oligodendrocyte precursor cells (OPCs). BED exposure antagonized NCX activity, induced OPCs proliferation and [Na] accumulation. By contrast, 2 days of BED washout after 4 days of treatment significantly upregulated low molecular weight NCX3 proteins, reversed NCX activity, and increased intracellular [Ca]. This BED-free effect was accompanied by an upregulation of NCX3 expression in oligodendrocyte processes and accelerated expression of myelin markers in rat primary oligodendrocytes. Collectively, our findings show that the pharmacological inhibition of the NCX3 exchanger with BED blocker maybe followed by a rebound increase in NCX3 expression and reversal activity that accelerate myelin sheet formation in oligodendrocytes. In addition, they indicate that a particular attention should be paid to the use of NCX inhibitors for possible rebound effects, and suggest that further studies will be necessary to investigate whether selective pharmacological modulation of NCX3 exchanger may be exploited to benefit demyelination and remyelination in demyelinating diseases.
钠钙交换体 NCX3 是少突胶质细胞系中钠和钙稳态的重要调节剂。迄今为止，尚无关于 NCX3 阻断剂长期暴露和随后药物洗脱对少突胶质细胞的影响的信息。在这里，我们通过生化、形态和功能分析研究了 NCX3 抑制剂 5-氨基-N-丁基-2-(4-乙氧基苯氧基)苯甲酰胺盐酸盐 (BED) 在人 MO3.13 少突胶质细胞和大鼠原代少突胶质前体细胞 (OPC) 中的治疗和药物洗脱期间对 NCXs 表达和活性以及细胞内 [Na] 和 [Ca] 水平的药理学作用。BED 暴露拮抗 NCX 活性，诱导 OPC 增殖和 [Na] 积累。相比之下，在治疗 4 天后用 BED 洗脱 2 天会显著上调低分子量 NCX3 蛋白，逆转 NCX 活性，并增加细胞内 [Ca]。这种无 BED 作用伴随着少突胶质细胞突起中 NCX3 表达的上调和髓鞘标记物在大鼠原代少突胶质细胞中的快速表达。总之，我们的研究结果表明，用 BED 阻断剂抑制 NCX3 交换体可能随后会出现 NCX3 表达和逆转活性的反弹增加，从而加速少突胶质细胞中的髓鞘形成。此外，它们表明在使用 NCX 抑制剂时应特别注意可能的反弹效应，并表明需要进一步研究以调查选择性药理学调节 NCX3 交换体是否可用于促进脱髓鞘疾病中的脱髓鞘和髓鞘再生。
