In vivo protective effect of ferulic acid against noise-induced hearing loss in the guinea-pig.
Ferulic acid (FA) is a phenolic compound whose neuroprotective activity was extensively studied in vitro. In this study, we provided functional in vivo evidence that FA limits noise-induced hearing loss. Guinea-pigs exposed to acoustic trauma for 1 h exhibited a significant impairment in auditory function; this injury was evident as early as 1 day from noise exposure and persisted over 21 days. Ferulic acid (150 mg/kg i.p. for 4 days) counteracted noise-induced hearing loss at days 1, 3, 7 and 21 from noise exposure. The improvement of auditory function by FA was paralleled by a significant reduction in oxidative stress, apoptosis and increase in hair cell viability in the organ of Corti. Interestingly in the guinea-pig cochleae, the neuroprotective effect of FA was functionally related not only to its scavenging ability in the peri-traumatic period but also to the up-regulation of the cytoprotective enzyme heme oxygenase-1 (HO-1); in fact, FA-induced improvement of auditory function was counteracted by the HO inhibitor zinc-protoporphyrin-IX and paralleled the time-course of HO-1 induction over 3-7 days. These results confirm the antioxidant properties of FA as free-radical scavenger and suggest a role of HO-1 as an additional mediator against noise-induced ototoxicity.
Fetoni
A R
AR
Institute of Otolaryngology, Catholic University School of Medicine, Largo Francesco Vito 1, 00168 Rome, Italy.
Mancuso
C
C
Eramo
S L M
SL
Ralli
M
M
Piacentini
R
R
Barone
E
E
Paludetti
G
G
Troiani
D
D
D000161:Acoustic Stimulation / Q000009:adverse effects; D000818:Animals; D003373:Coumaric Acids / Q000494:pharmacology* / Q000627:therapeutic use; D004195:Disease Models, Animal; D016166:Free Radical Scavengers / Q000494:pharmacology* / Q000627:therapeutic use; D006168:Guinea Pigs; D006198:Hair Cells, Auditory / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D006317:Hearing Loss, Noise-Induced / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology; D018696:Neuroprotective Agents / Q000494:pharmacology* / Q000627:therapeutic use; D009622:Noise / Q000009:adverse effects
D003373:Coumaric Acids; D016166:Free Radical Scavengers; D018696:Neuroprotective Agents; C004999:ferulic acid