Kang Seol-Hee, Lee Hae-Ahm, Lee Eunjo, Kim Mina, Kim Inkyeom
Department of Pharmacology, Cardiovascular Research Institute, Cell and Matrix Research Institute, Kyungpook National University School of Medicine, Daegu, Korea.
BK21 Plus KNU Biomedical Convergence Program, Department of Biomedical Science, Kyungpook National University School of Medicine, Daegu, Korea.
Clin Exp Pharmacol Physiol. 2016 Oct;43(10):995-1003. doi: 10.1111/1440-1681.12614.
A mutation in the mineralocorticoid receptor (MRS 810L ) leads to early-onset hypertension, which is markedly exacerbated during pregnancy. The mutation causes progesterone and even the MR antagonist spironolactone to become potent agonists. Thus, it is hard to control hypertension in patients harbouring this mutation. We hypothesized that histone deacetylase inhibition (HDACi), but not the MR antagonist spironolactone, attenuates atypical transcriptional activity of activating mutant MR (MRS 810L ). We established HEK293T cells overexpressing wild-type MR (MRWT ) or MRS 810L and determined their transcriptional activities by luciferase assay. Expression of MR target genes was measured by quantitative real-time PCR (qRT-PCR). Treatment with aldosterone increased the expression of MR target genes as well as the transcriptional activities in HEK293T cells transfected either with MRWT or MRS 810L . Treatment with either spironolactone or progesterone also increased the expression of MR target genes as well as transcriptional activity, but only in HEK293T cells transfected with MRS 810L . Spironolactone abolished the promoter activity stimulated by aldosterone in HEK293T cells transfected with MRWT . Treatment with HDAC inhibitors attenuated the transcriptional activity as well as the expression of MR target genes induced by aldosterone, spironolactone, or progesterone whether HEK293T cells were transfected with either MRWT or MRS 810L . These results indicate that HDACi, but not an MR antagonist spironolactone, attenuates atypical transcriptional activity of an activating mutant MR (MRS 810L ).
盐皮质激素受体（MRS 810L）的一种突变会导致早发性高血压，在孕期会显著加重。该突变使孕酮甚至MR拮抗剂螺内酯变成强效激动剂。因此，携带这种突变的患者很难控制高血压。我们推测，组蛋白去乙酰化酶抑制（HDACi）而非MR拮抗剂螺内酯，可减弱激活型突变MR（MRS 810L）的非典型转录活性。我们构建了过表达野生型MR（MRWT）或MRS 810L的HEK293T细胞，并通过荧光素酶测定法确定它们的转录活性。通过定量实时PCR（qRT-PCR）检测MR靶基因的表达。用醛固酮处理可增加MR靶基因的表达以及在转染了MRWT或MRS 810L的HEK293T细胞中的转录活性。用螺内酯或孕酮处理也增加了MR靶基因的表达以及转录活性，但仅在转染了MRS 810L的HEK293T细胞中。螺内酯消除了醛固酮在转染了MRWT的HEK293T细胞中刺激的启动子活性。无论HEK293T细胞是转染了MRWT还是MRS 810L，用HDAC抑制剂处理都减弱了醛固酮、螺内酯或孕酮诱导的转录活性以及MR靶基因的表达。这些结果表明，HDACi而非MR拮抗剂螺内酯可减弱激活型突变MR（MRS 810L）的非典型转录活性。
