A senescence accelerated mouse model to study aging in the larynx

Area of Science:

• Gerontology
• Otolaryngology
• Molecular Biology

Background:

• Age-related laryngeal changes cause voice impairment and reduced quality of life.
• Existing aged animal models have lengthy generation times, hindering research on aging voices.
• Senescence accelerated prone mice (SAMP) naturally exhibit rapid aging, making them suitable for studying age-related conditions.

Purpose of the Study:

• To evaluate senescence accelerated mice (SAMP) as a model for studying age-related laryngeal changes.
• To investigate the molecular and histological alterations in the larynx of SAMP mice compared to control groups.

Main Methods:

• Harvested larynges from SAMP mice, senescence resistant mice, and C57BL/6 mice.
• Performed histomorphometry to assess collagen and hyaluronic acid distribution.
• Quantified collagen-1 mRNA and protein levels, and myofibroblast markers (alpha-smooth muscle actin).

Main Results:

• SAMP mice showed increased collagen deposition and collagen-1 mRNA in vocal folds by six months.
• Higher concentrations of alpha-smooth muscle actin were observed in SAMP vocal fold tissue.
• Hyaluronic acid levels decreased with age in SAMP mice compared to controls.

Conclusions:

• SAMP mice demonstrate accelerated, age-related vocal fold changes as early as six months.
• This model shows potential for studying age-related laryngeal dysfunction and developing therapeutics.
• Senescence accelerated mice provide a valuable tool for understanding vocal aging mechanisms.