Table 1.
Studies on the protective effect of antioxidants on various SNHL.
| Drug | Experimental design | Outcome | Mechanism | Reference |
|---|---|---|---|---|
| MT | Animal experiment: rats | DPOAE: M+RT group and RT+M group>RT group | Inhibit production of ROS7; enhance the DNA repair process | [89] |
| AMF | Animal experiment: guinea pigs | Degree of cochlear hair cell damage: IRR + AMF group < RT group. No difference between 100 mg/kg and 200 mg/kg AMF groups |
Be hydrolyzed into active component in vivo, which has sulfhydryl group that scavenges free radicals | [90] |
| LC | Animal experiment: guinea pigs | Histopathological examination: LC can ameliorate radiation-induced cochlear damage in guinea pigs. | Improving mitochondrial oxygen utilization and scavenging free-radicals | [91] |
| MP | Clinical trials: NPC patients | Pure tone audiometry; DPOAE; ABR: the use of MP during RT can reduce the early RISNHL | Mechanisms to protect the OHC: 1. Affects transcription and inhibits caspase-mediated apoptosis 2. Inhibits inflammatory response 3. Promotes GSH synthesis |
[92] |
| PIR | Animal experiment: male albino guinea pigs | Histopathologic examination: PIR might reduce radiation-induced cochlear damage in guinea pigs | Increases oxygenation in the tumor cells with its rheological effects and decreases apoptosis in surrounding healthy cells | [93] |
| EC | Cell experiment: HEI-OC1 and UB-OC1 Animal experiment: embryos/rats |
EC can increase the survival rate of HEI-OC1 cells after radiotherapy. EC can inhibit the ABR threshold in the rats. |
Inhibits ROS production and MAPK activity | [94] |
MT: melatonin; AMF: amifostine; LC: L-carnitine; MP: methylprednisolone; PIR: piracetam; EC: epicatechin; GSH: glutathione.