Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, POB 260, Budapest 1444, Hungary.
J Neural Transm (Vienna). 2012 Jan;119(1):17-24. doi: 10.1007/s00702-011-0688-4. Epub 2011 Jul 23.
Histone deacetylase inhibitors are promising anti-tumor agents partly due to their ability to disrupt the hypoxic signaling pathway in human malignancies. However, little is known about any effects of these drugs on the central nervous system. The aim of the present study was to analyze the effects of trichostatin A (TSA)--a broad-spectrum histone deacetylase inhibitor--on the transcriptional regulation of several genes involved in dopamine- and serotonergic neurotransmission. To this end, short-term parallel cultures of SK-NF-I neuroblastoma cells were treated with TSA either alone or in combination with hypoxia, and mRNA levels of dopamine receptor D3 (DRD3) and D4 (DRD4), dopamine transporter (DAT), dopamine hydroxylase (DBH), dopamine receptor regulating factor (DRRF), catechol-O-methyltransferase (COMT), serotonin receptor 1A (HTR1A), monoamino oxidase A (MAO-A), serotonin transporter (SLC6A4) and tryptophan hydroxylase 2 (TPH2) were determined by quantitative PCR. We found that TSA did not antagonize the hypoxia-induced activation of D3 and D4 dopamine receptor genes, implying that induction of these genes is not mediated directly by hypoxia inducible factor-1alpha. On the other hand, TSA dramatically upregulated the expression of DAT and SLC6A4 (45-fold and 15-fold, respectively), while transcript levels of MAO-A and COMT were significantly reduced (by 70% and by more than 90%, respectively). Induction of DAT protein expression was detected by western blotting. These results suggest that inhibition of histone deacetylases might help restore presynaptic monoamine pools via suppression of catecholamine breakdown and facilitation of monoamine reuptake in neurons.
组蛋白去乙酰化酶抑制剂是很有前途的抗肿瘤药物，部分原因是它们能够破坏人类恶性肿瘤中的低氧信号通路。然而，人们对这些药物对中枢神经系统的任何影响知之甚少。本研究旨在分析曲古抑菌素 A（TSA）——一种广谱组蛋白去乙酰化酶抑制剂——对涉及多巴胺和 5-羟色胺能神经递质的几个基因的转录调控的影响。为此，SK-NF-I 神经母细胞瘤细胞的短期平行培养物单独或与低氧条件下用 TSA 处理，并通过定量 PCR 测定多巴胺受体 D3（DRD3）和 D4（DRD4）、多巴胺转运体（DAT）、多巴胺羟化酶（DBH）、多巴胺受体调节因子（DRRF）、儿茶酚-O-甲基转移酶（COMT）、5-羟色胺受体 1A（HTR1A）、单胺氧化酶 A（MAO-A）、5-羟色胺转运体（SLC6A4）和色氨酸羟化酶 2（TPH2）的 mRNA 水平。我们发现，TSA 并没有拮抗低氧诱导的 D3 和 D4 多巴胺受体基因的激活，这表明这些基因的诱导不是由缺氧诱导因子-1alpha 直接介导的。另一方面，TSA 显著上调了 DAT 和 SLC6A4 的表达（分别上调了 45 倍和 15 倍），而 MAO-A 和 COMT 的转录水平则显著降低（分别降低了 70%和 90%以上）。通过 Western blot 检测到 DAT 蛋白表达的诱导。这些结果表明，组蛋白去乙酰化酶的抑制可能有助于通过抑制儿茶酚胺的分解和促进单胺的再摄取来恢复神经元中的前突触单胺池。
