Protective Effects of Silymarin Against Age-Related Hearing Loss in an Aging Rat Model

AbstractAge-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 ad-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/dayd-Gal plus 100, 200 and 300  mg/kg/day silymarin respectively for 8 weeks, placebo group received 500 mg/kg/dayd-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 (P <  0.05). However, rats treated with silymarin 100 and 200 mg/kg/day plusd-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 (P <  0.05). However, no significant differences are found in ABR absolute and in...
Source: Indian Journal of Otolaryngology and Head and Neck Surgery - Category: ENT & OMF Source Type: research