Effects of Spirulina on GABA-Receptor Gene Expression in Salicylate-Induced Tinnitus

Objectives: The function of γ-amino butyric acid receptor (GR) was related with tinnitus. But, the effects of Spirulina platensis water extract (SP) on the mRNA expression of GRA β 3 in mice with tinnitus were still unclear. Method: Eighteen SAMP8 mice were divided into the control group (intraperitoneal injection of saline, once per day), the tinnitus group (intraperitoneal injection of salicylate, 300 mg/kg body weight once per day), and the spirulina group [intraperitoneal injection of salicylate, 300 mg/kg body weight and oral SP supplementation (1000 mg/kg body weight) once per day]. Effects of SP on the mRNA expression of GRA β 3 in the cochlea and brain of mice were studied for 4 days. Results: Compared to the control group, the tinnitus group had significantly higher tinnitus scores and lower mRNA expression of GRA β 3 gene in the cochlear, brainstem, hippocampus and parahippocampus, temporal lobes, and the frontal lobes. On the other hand, the spirulina group had significantly lower tinnitus scores and higher GRA β 3 gene expression than the tinnitus group in all tested areas. Conclusion: SP could reduce salicylate-induced tinnitus possibly via increasing the salicylate-induced down-regulation of GRA β 3 gene expression.