Auditory impairment in guinea pigs treated with isepamicin

Area of Science:

• Ototoxicity studies
• Pharmacology
• Auditory science

Background:

• Aminoglycosides are a class of antibiotics with potential ototoxic side effects.
• Isepamicin is an aminoglycoside antibiotic used in clinical practice.
• Assessing the ototoxicity of new or existing drugs is crucial for patient safety.

Purpose of the Study:

• To evaluate the ototoxic potential of isepamicin in adult guinea pigs.
• To compare the ototoxicity of isepamicin with amikacin, a known ototoxic aminoglycoside.
• To determine dose-dependent effects of isepamicin on auditory function and cochlear morphology.

Main Methods:

• Adult guinea pigs were administered isepamicin (100, 150, 225 mg/kg/day) or amikacin (225 mg/kg/day) intramuscularly for 21 days.
• Auditory function was assessed using the Preyer pinna reflex and brain stem evoked response.
• Cochlear morphology was evaluated using scanning electron microscopy and light microscopy.

Main Results:

• Both isepamicin and amikacin at 225 mg/kg/day impaired auditory function and caused significant damage to the organ of Corti.
• Isepamicin at 150 mg/kg/day showed a lesser degree of auditory impairment and cochlear damage.
• Isepamicin at 100 mg/kg/day did not result in auditory impairment or significant morphological changes.

Conclusions:

• Isepamicin exhibits dose-dependent ototoxicity in guinea pigs, similar to amikacin at high doses.
• The 225 mg/kg/day dose of isepamicin is associated with significant auditory and cochlear toxicity.
• Lower doses, such as 100 mg/kg/day, appear to be safe regarding ototoxicity in this animal model.