Expression comparison of TLR2 in patients with sudden deaf

Abstract

More than 80% of hearing loss is sudden sensi-neural hearing loss (SSNHL), defined as sudden hearing loss of 30 dB or more with three intermittent and continuous frequencies over a period of three days or less. The aim of this study is to investigation of the expression comparison of TLR2 in patients with sudden deaf. Materials and Methods: In this retrospective study, 80 samples were examined equally in two groups of 40 patients with SSNHL whose disease was confirmed by a specialist and healthy individuals without hearing impairment. The sampling method of this design was easy to access. After selecting the patients, blood samples were collected from the participants (after obtaining informed consent) in the amount of 5 cc of blood. To protect the RNAs, the samples were quickly transferred to -80 ° C. RNA was extracted from the blood using a traysol solution; then, cDNA synthesis for the genes was performed using cDNA synthesis kits. Finally, using Real Time PCR kit and specific primers of the studied genes, the expression of target genes in the samples was evaluated. The data obtained from measuring the expression of these genes were normalized by measuring the expression level of a house keeping gene called GAPDH and then compared. Results: In this study, the mean (standard deviation) age of the two groups of patients with SSNHL and healthy individuals without hearing impairment was 55.48 (±2.3) and 56.80 (±2.6) years old, respectively. In the group of patients with SSNHL, the side of the auditory involvement was left in 18 cases (45.0%) and right in 22 cases (55.0%), respectively. Also, the highest severity of hearing loss was moderate in the group of patients with SSNHL, with 18 cases (45.0%), followed by mild, severe and profound hearing loss of 10 cases (25.0%), 7 cases (17.5%) and 5 cases (12.5%), respectively. The expression level of TLR2 gene was not significantly different between men and women (P-value = 0.524); On the other hand, the expression level of TLR2 gene in the group of patients with SSNHL was significantly more than healthy individuals without hearing impairments (P-value = 0.032). Due to the lack of significance of the area under the ROC curve (P-value = 0.057), the TLR2 gene did not have the appropriate ability to distinguish patients with SSNHL from healthy individuals without hearing impairments.