Post-translational modifications and age-related hearing loss.

Post-translational modifications (PTMs) affect nearly all systems of the human body due to their role in protein synthesis and functionality. These reversible and irreversible modifications control the structure, localization, activity, and properties of proteins. For this reason, PTMs are essential in regulating cellular processes and maintaining homeostasis. Diseases such as Alzheimer's, cardiovascular disease, diabetes, cancer, and many others have been linked to dysfunctions of PTMs. Recent research has also shown that irregularities in PTMs can be linked to hearing loss, including age-related hearing loss (ARHL) - the number one communication disorder and one of the top neurodegenerative diseases in our aging population. So far, there has been no FDA approved treatment for ARHL; however, translational studies investigating PTMs involvement in ARHL show promising results. In this review, we summarize key findings for PTMs within the auditory system, the involvement of PTMs with aging and ARHL, and lastly discuss potential treatment options focusing on utilizing PTMs as biomarkers and therapeutic pathway components.

Cochlear Inflammaging in Relation to Ion Channels and Mitochondrial Functions.

The slow accumulation of inflammatory biomarker levels in the body-also known as inflammaging-has been linked to a myriad of age-related diseases. Some of these include neurodegenerative conditions such as Parkinson's disease, obesity, type II diabetes, cardiovascular disease, and many others. Though a direct correlation has not been established, research connecting age-related hearing loss (ARHL)-the number one communication disorder and one of the most prevalent neurodegenerative diseases of our aged population-and inflammaging has gained interest. Research, thus far, has found that inflammatory markers, such as IL-6 and white blood cells, are associated with ARHL in humans and animals. Moreover, studies investigating ion channels and mitochondrial involvement have shown promising relationships between their functions and inflammaging in the cochlea. In this review, we summarize key findings in inflammaging within the auditory system, the involvement of ion channels and mitochondrial functions, and lastly discuss potential treatment options focusing on controlling inflammation as we age.