Plate reader-based cell viability assays for glioprotection using primary rat optic nerve head astrocytes

Area of Science:

• Neuroscience
• Ophthalmology
• Cell Biology

Background:

• Optic nerve head astrocytes (ONHAs) are vital glial cells in the optic nerve head, crucial for extracellular matrix synthesis and retinal ganglion cell function.
• Glaucoma and related optic nerve disorders involve astrocyte activation, extracellular matrix remodeling, and oxidative stress, leading to axon damage.
• Glioprotective strategies targeting ONHAs are essential for preserving vision in glaucoma and related pathologies.

Purpose of the Study:

• To develop and standardize methods for isolating, culturing, and assessing primary adult rat ONHAs.
• To establish plate reader-based assays for evaluating ONHA viability, proliferation, and redox state.
• To validate these protocols by assessing the efficacy of an antioxidant (Trolox) against oxidative stress in ONHAs.

Main Methods:

• Isolation, purification, and culture of primary adult rat ONHAs.
• Immunocytochemical validation of astrocyte identity.
• Plate reader-based assays using tert-butylhydroperoxide (tBHP) for oxidative stress induction and measuring cell viability (LDH, MTT) and redox state (DCFDA).

Main Results:

• Standardized protocols were established for ONHA culture and assessment.
• tBHP induced significant oxidative stress, cell death, and reduced viability in ONHAs (EC50 values provided).
• Pre-treatment with Trolox significantly protected ONHAs against tBHP-induced damage, increasing resistance to oxidative stress.

Conclusions:

• The developed standardized protocols are feasible for assessing glioprotective agents in primary rat ONHAs.
• Antioxidant treatment effectively enhances ONHA viability and mitigates oxidative stress, supporting their role in neuroprotection.
• These protocols can be adapted for high-throughput screening of novel therapeutics for glaucoma and related optic neuropathies.