title: Glutathione S-transferase M1, T1, and P1 polymorphisms as susceptibility factors for noise-induced temporary threshold shift.
abstract: The generation of reactive oxygen species (ROS) is thought to be part of the mechanism underlying noise-induced hearing loss (NIHL). Glutathione is an important cellular antioxidant that limits cell damage by ROS. We aimed to determine the effect of genetic polymorphisms of glutathione S-transferase (GST) T1, GSTM1, and GSTP1, on temporary threshold shift (TTS) in 58 noise-exposed male workers from a steel factory. The pre-shift hearing impairment at high frequency (HF, average of 3, 4, and 6kHz) was 30.7dB HL (S.D.=19.3). The amount of daily noise exposure was 83.0dBA (S.D.=5.0). Noise-induced TTS at HF by pure-tone audiometry (PTA) was related to the daily noise exposure (p<0.05). Based on combinatory analysis, we found that individuals carrying all genotypes with GSTT1 null, GSTM1 null, and GSTP1 Ile(105)/Ile(105) were more susceptible to NIHL. These results suggest that pre-shift hearing impairment and daily noise exposure had impacts on TTS at HF by PTA. In addition, GST genetic polymorphisms may modify the susceptibility to noise-induced TTS.
authors: Department of Otolaryngology, Tainan Municipal Hospital, East District, Tainan City 701, Taiwan. yu621109@ms48.hinet.net
authors: Cheng-Yu
authors: CY
authors: Lin
authors: Jiunn-Liang
authors: JL
authors: Wu
authors: Tung-Sheng
authors: TS
authors: Shih
authors: Perng-Jy
authors: PJ
authors: Tsai
authors: Yih-Min
authors: YM
authors: Sun
authors: Yueliang Leon
authors: YL
authors: Guo
mesh_terms: D000328:Adult; D001301:Audiometry, Pure-Tone; D001309:Auditory Threshold; D020022:Genetic Predisposition to Disease; D051549:Glutathione S-Transferase pi / Q000235:genetics*; D005982:Glutathione Transferase / Q000235:genetics*; D006317:Hearing Loss, Noise-Induced / Q000201:enzymology / Q000209:etiology / Q000235:genetics* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008669:Metallurgy; D008875:Middle Aged; D009623:Noise, Occupational / Q000009:adverse effects*; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide; D012044:Regression Analysis; D018570:Risk Assessment; D012307:Risk Factors
chemical_list: D051549:Glutathione S-Transferase pi; D005982:Glutathione Transferase; C496556:GSTP1 protein, human; C495790:glutathione transferase T1-1, human