Department of Otolaryngology-Head and Neck Surgery, The Affiliated Children Hospital of Xi'an Jiaotong University, Xi'an, China.
Department of Otolaryngology-Head and Neck Surgery, Xijing Hospital, Xi'an, China.
Int J Immunopathol Pharmacol. 2021 Jan-Dec;35:20587384211034086. doi: 10.1177/20587384211034086.
Cruciferous vegetables are a rich source of sulforaphane (SFN), which acts as a natural HDAC inhibitor (HDACi). Our previous study found that HDACi could restore histone acetyltransferase/histone deacetylase (HAT/HDAC) balance in the cochlea and attenuate gentamicin-induced hearing loss in guinea pigs. Here, we investigated the protective effect of SFN on cisplatin-induced hearing loss (CIHL).
Thirty rats were randomly divided into 3 equal groups: the control group, cisplatin group, and SFN+cisplatin group. Rats were injected with SFN (30 mg/kg once a day) and cisplatin (7 mg/kg twice a day) for 7 days to investigate the protective role of SFN on CIHL. We observed auditory brainstem response (ABR) threshold shifts and immunostained cochlear basilar membranes of rats. For in vitro experiments, we treated HEI-OC1 cells and rat cochlear organotypic cultures with SFN (5, 10, and 15 μM) and cisplatin (10 μM). Immunofluorescence, cell viability, and protein analysis were performed to further analyze the protective mechanism of SFN on CIHL.
SFN (30 mg/kg once a day) decreased cisplatin (7 mg/kg twice a day)-induced ABR threshold shifts and outer hair cell loss. CCK-8 assay showed that cisplatin (10 μM) reduced the viability of HEI-OC1 cells to 42%, and SFN had a dose-dependent protective effect. In cochlear organotypic cultures, we found that SFN (10 and 15 μM) increased cisplatin (10 μM)-induced myosin 7a cell count and restored ciliary morphology. SFN (5, 10, and 15 μM) reversed the cisplatin (10 μM)-induced increase in HDAC2, -4, and -5 and SFN (15 μM) reversed the cisplatin (10 μM)-induced decrease in H3-Ack9 [acetyl-histone H3 (Lys9)] protein expression in HEI-OC1 cells. Neither cisplatin nor cisplatin combined with SFN affected the expression of HDAC7, or HDAC9.
SFN prevented disruption of the HAT/HDAC balance, protecting against CIHL in rats.
十字花科蔬菜是硫代葡萄糖苷（SFN）的丰富来源，SFN 可作为天然组蛋白去乙酰化酶抑制剂（HDACi）。我们之前的研究发现，HDACi 可恢复耳蜗中的组蛋白乙酰转移酶/组蛋白去乙酰化酶（HAT/HDAC）平衡，并减轻庆大霉素诱导的豚鼠听力损失。在这里，我们研究了 SFN 对顺铂诱导的听力损失（CIHL）的保护作用。
30 只大鼠随机分为 3 组：对照组、顺铂组和 SFN+顺铂组。大鼠每天注射 SFN（30mg/kg，一次）和顺铂（7mg/kg，两次），以研究 SFN 对 CIHL 的保护作用。我们观察了大鼠的听性脑干反应（ABR）阈值变化，并对耳蜗基底膜进行了免疫染色。在体外实验中，我们用 SFN（5、10 和 15μM）和顺铂（10μM）处理 HEI-OC1 细胞和大鼠耳蜗器官型培养物。进行免疫荧光、细胞活力和蛋白质分析，以进一步分析 SFN 对 CIHL 的保护机制。
SFN（30mg/kg，一次）降低了顺铂（7mg/kg，两次）诱导的 ABR 阈值变化和外毛细胞损失。CCK-8 测定表明，顺铂（10μM）将 HEI-OC1 细胞的活力降低至 42%，SFN 具有剂量依赖性的保护作用。在耳蜗器官型培养物中，我们发现 SFN（10 和 15μM）增加了顺铂（10μM）诱导的肌球蛋白 7a 细胞计数，并恢复了纤毛形态。SFN（5、10 和 15μM）逆转了顺铂（10μM）诱导的 HDAC2、-4 和 -5 增加，SFN（15μM）逆转了顺铂（10μM）诱导的 H3-Ack9[乙酰化组蛋白 H3（Lys9）]蛋白表达减少在 HEI-OC1 细胞中。顺铂或顺铂联合 SFN 均不影响 HDAC7 或 HDAC9 的表达。
SFN 防止了 HAT/HDAC 平衡的破坏，防止了大鼠的 CIHL。
