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Updated: Jan 29, 2026
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Dissection of Human Retina and RPE-Choroid for Proteomic Analysis
Published on: November 12, 2017
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Localization of nitro-tyrosine immunoreactivity in human retina
Tapas C Nag1, Poorti Kathpalia1, Shilpa Gorla1
1Department of Anatomy, Neurobiology Laboratory, All India Institute of Medical Sciences, New Delhi, 110029, India.
Summary
Nitrosative stress, indicated by nitro-tyrosine, occurs in aging human retinas, particularly in photoreceptor cells. This biomarker is linked to abnormal changes in photoreceptor axons, suggesting a role in retinal aging and disease.
Area of Science:
- Ophthalmology
- Neuroscience
- Cell Biology
Background:
- Oxidative stress is linked to retinal aging and age-related macular degeneration (AMD).
- Lipid peroxidation markers are found in retinal cells in aging and AMD.
- The role of nitrosative stress in the aging human retina is not well understood.
Purpose of the Study:
- To investigate the presence and cellular localization of nitrosative stress in the aging human retina.
- To examine if nitro-tyrosine, a biomarker of protein tyrosine nitration, is present in aging human retinas.
- To correlate nitro-tyrosine presence with photoreceptor axonal changes.
Main Methods:
- Immunohistochemistry was used to detect nitro-tyrosine in human donor retinas (age range: 17-91 years).
- Transmission electron microscopy was employed to examine axonal morphology.
- Cellular localization of nitro-tyrosine immunoreactivity was analyzed.
Main Results:
- Nitro-tyrosine immunoreactivity was detected in 10 out of 15 retinas, predominantly in photoreceptor inner segments, cell bodies, and axons.
- Abnormal, swollen axons were observed in cone photoreceptors of six retinas.
- Microtubule disorganization and abnormal axonal outgrowths were noted in affected axons.
Conclusions:
- Nitrosative stress, evidenced by nitro-tyrosine, is present in select aging human retinas.
- Nitro-tyrosine immunoreactivity is associated with photoreceptor cells and aberrant axonal changes.
- These findings contribute to understanding molecular changes in the aging retina.
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