Tavanai Elham, Mohammadkhani Ghassem, Farahani Saeid, Jalaie Shohreh
Department of Audiology, School of Rehabilitation, Tehran University of Medical Sciences, Pich-e-Shemiran, Enghelab Ave, Tehran, Iran.
Indian J Otolaryngol Head Neck Surg. 2019 Nov;71(Suppl 2):1248-1257. doi: 10.1007/s12070-018-1294-7. Epub 2018 Mar 14.
Age-related hearing loss (ARHL) is one of the most common chronic degenerative disorders. Several studies have indicated that supplementation with some antioxidants can slow down the progression of ARHL. Despite several lines of evidence about the potent antioxidant and anti-aging effects of silymarin, its protective effect against ARHL has not evaluated yet. The aim of the current study was to investigate the effects of silymarin in prevention of ARHL in a d-Galactose-induced aging rat model for the first time. 45 male wistar rats aged 3-month old were divided into 5 groups: group 1, 2 and 3 received 500 mg/kg/day d-Gal plus 100, 200 and 300 mg/kg/day silymarin respectively for 8 weeks, placebo group received 500 mg/kg/day d-Gal plus propylene glycol as placebo, and control group received normal saline during this period of time. Auditory brainstem responses were measured at several frequencies (4, 6, 8, 12 and 16 kHz) before and after the intervention. Placebo group and group 3 showed significant ABR threshold increase across frequencies of 4, 6, 16 kHz compared with the other groups ( < 0.05). However, rats treated with silymarin 100 and 200 mg/kg/day plus d-Gal did not show any significant ABR threshold shifts. Similarly, ABR amplitude of P2 at 4, 8 kHz and P1, P4 at 4 kHz in the placebo group and group 3 were decreased significantly compared with other groups ( < 0.05). However, no significant differences are found in ABR absolute and inter-peak latencies between groups ( > 0.05). The findings indicates that silymarin with doses of 100 and 200 mg/kg/day has protective effect against ARHL and it can be supplemented into the diet of older people to slow down the progression of age-related hearing loss.
年龄相关性听力损失（ARHL）是最常见的慢性退行性疾病之一。多项研究表明，补充某些抗氧化剂可以减缓ARHL的进展。尽管有多项证据表明水飞蓟宾具有强大的抗氧化和抗衰老作用，但其对ARHL的保护作用尚未得到评估。本研究的目的是首次在d-半乳糖诱导的衰老大鼠模型中研究水飞蓟宾对预防ARHL的作用。将45只3个月大的雄性Wistar大鼠分为5组：第1组、第2组和第3组分别接受500mg/kg/天的d-半乳糖加100、200和300mg/kg/天的水飞蓟宾，持续8周，安慰剂组接受500mg/kg/天的d-半乳糖加丙二醇作为安慰剂，对照组在此期间接受生理盐水。在干预前后测量几个频率（4、6、8、12和16kHz）的听觉脑干反应。与其他组相比，安慰剂组和第3组在4、6、16kHz频率上的ABR阈值显著升高（<0.05）。然而，接受100和200mg/kg/天水飞蓟宾加d-半乳糖治疗的大鼠未显示出任何显著的ABR阈值变化。同样，与其他组相比，安慰剂组和第3组在4、8kHz时P2的ABR振幅以及在4kHz时P1、P4的ABR振幅显著降低（<0.05）。然而，各组之间的ABR绝对潜伏期和峰间潜伏期没有显著差异（>0.05）。研究结果表明，100和200mg/kg/天剂量的水飞蓟宾对ARHL具有保护作用，可添加到老年人的饮食中以减缓年龄相关性听力损失的进展。
