Effects of Curcumin in Workers with Noise-Induced Hearing Loss: Preliminary Report

Introduction:Prolonged loud noise exposure causes sensorineural hearing loss through cochlear oxidative stress, requiring heat shock protein ۷۰ (HSP۷۰) for protection. Curcumin boosts antioxidant expression and safeguards the cochlea. Pure tone audiometry (PTA) measures the type of hearing loss and otoacoustic emission (OAE) detects early auditory issues. This study evaluated the impact of Curcumin on noise-exposed workers via PTA, OAE, and HSP۷۰.Materials and Methods: This preliminary study included ۵۴ noise-exposed workers with hearing thresholds ≥۲۶ dB and SNR values <۶ dB. Participants were randomized into three noise-exposed groups: placebo (positive control), ۵۰۰ mg Curcumin, or ۱,۰۰۰ mg Curcumin for ۴ weeks. A negative control group of ۱۸ non-exposed workers with normal hearing who received no treatment, served as an external reference only. HSP۷۰ levels, PTA, and OAE were measured before and after intervention in all groups.Results: PTA showed a significant worsening of hearing threshold in the positive control group (p=۰.۰۰۱), significant improvement in Curcumin ۵۰۰ mg group (p=۰.۰۴۶), in the Curcumin ۱,۰۰۰ mg (p=۰.۰۵۹). OAE revealed substantial worsening of SNR in the positive control group (p<۰.۰۰۱) and significant increase in the Curcumin ۵۰۰ mg (p<۰.۰۵) at ۴, ۷, ۸, and ۹ kHz, and in the ۱,۰۰۰ mg groups (p<۰.۰۵) at ۵, ۸, and ۹ kHz. HSP۷۰ levels significantly increased in the positive control group (p=۰.۰۲۱), both Curcumin groups showed a non-significant increase.Conclusion: Curcumin was associated with improved hearing thresholds and favorable SNR changes in noise-exposed workers. Changes in HSP۷۰ levels were minimal and not statistically significant in the curcumin groups.

کلیدواژه ها:

Curcumin ، Heat shock protein ۷۰ ، Noise-induced hearing loss ، Pure tone audiometry ، Otoacoustic emission