Related Experiment Video
Updated: Jul 14, 2026
05:18
Quantification of Immunostained Caspase-9 in Retinal Tissue
Published on: July 25, 2022
Caspase-dependent apoptosis in light-induced retinal degeneration
Olivier Perche1, Michel Doly, Isabelle Ranchon-Cole
1Laboratoire de Biophysique Sensorielle, Université Clermont 1, Clermont-Ferrand, France. olivier.perche@u-clermont1.fr
Investigative Ophthalmology & Visual Science
|May 26, 2007
Summary
Light-induced retinal degeneration in rats involves caspase-dependent photoreceptor cell death. Specific caspase inhibitors like Z-VAD-FMK and Z-DEVD-FMK protected retinal function and structure.
Area of Science:
- Ophthalmology
- Neuroscience
- Cell Biology
Background:
- Light-induced retinal degeneration is a significant cause of vision loss.
- Understanding the molecular mechanisms of photoreceptor cell death is crucial for developing effective treatments.
Purpose of the Study:
- To investigate the apoptotic pathways involved in a rat model of light-induced retinal degeneration.
- To evaluate the protective effects of caspase inhibitors on photoreceptor cells.
Main Methods:
- Rats were exposed to constant light after intravitreal injection of various agents, including caspase inhibitors (Z-VAD-FMK, Z-YVAD-FMK, Z-DEVD-FMK).
- Retinal function (electroretinograms) and outer nuclear layer (ONL) thickness were assessed.
- Caspase and calpain activities were measured before and after light exposure.
Main Results:
- Caspase inhibitors Z-VAD-FMK and Z-DEVD-FMK significantly preserved retinal function and ONL thickness compared to controls.
- These inhibitors reduced the number of apoptotic photoreceptors by threefold.
- While inhibiting caspase-1 and -3, the inhibitors did not affect calpain activity.
Conclusions:
- Photoreceptor cell death in this model occurs via a caspase-dependent mechanism.
- The study highlights the potential of caspase inhibitors for treating light-induced retinal degeneration.
- Different proteases may be involved in the molecular events during and after light exposure.
Related Concept Videos
01:24Caspases
Caspase, a family of cysteine proteases, serve as effectors in apoptosis. The ced3 gene in C.elegans was first identified to be involved in apoptosis. This gene encodes the ced-3 caspase that is similar to the interleukin-1-beta converting enzyme or ICE in mammals. In addition to apoptosis, caspases also function in the inflammatory response. Inflammatory caspases are essential in activating pro-inflammatory cytokines that recruit immune cells and block the replication of pathogens inside cells.
01:22Cellular Injury V: Apoptosis and Autophagy
Cells respond to damage and stress through highly coordinated processes that decide whether they survive or undergo controlled self-destruction. Two major pathways involved in this regulation are apoptosis, a type of programmed cell death, and autophagy, a survival mechanism that helps cells adapt to adverse conditions.ApoptosisApoptosis removes aged or injured cells to maintain tissue balance. During this process, the cell shrinks, chromatin condenses and fragments, and membrane-bound...
01:17The Extrinsic Apoptotic Pathway
The extrinsic apoptotic pathway is initiated when extracellular death-inducing signals, such as specific cytokines, activate the death receptors expressed on the cell surface. The immune cells involved in this pathway are natural killer cells (NK cells) and cytotoxic T-lymphocytes. NK cells are critical in innate immune response, while cytotoxic T-lymphocytes are associated with adaptive immune response. These cells recognize specific receptors expressed on the altered cells and activate...
01:31The Intrinsic Apoptotic Pathway
Internal cellular stress, such as cellular injury or hypoxia, triggers intrinsic apoptosis. The B-cell lymphoma 2 (Bcl-2) family of proteins are the primary regulators of the intrinsic apoptotic pathway. For example, during DNA damage, checkpoint proteins, such as Ataxia Telangiectasia Mutated (ATM protein) and Checkpoints Factor-2 (Chk2) proteins, are activated. These proteins phosphorylate p53 which further activates pro-apoptotic proteins, such as Bax, Bak, PUMA, and Noxa, and inhibits...