Related Experiment Videos
Microglia-Müller glia cell interactions control neurotrophic factor production during light-induced retinal
Takayuki Harada1, Chikako Harada, Shinichi Kohsaka
1Department of Degenerative Neurological Diseases, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo 187-8502, Japan.harada.aud@mri.tmd.ac.jp
Abstract:
Activation of microglia commonly occurs in response to a wide variety of pathological stimuli including trauma, axotomy, ischemia, and degeneration in the CNS. In the retina, prolonged or high-intensity exposure to visible light leads to photoreceptor cell apoptosis. In such a light-reared retina, we found that activated microglia invade the degenerating photoreceptor layer and alter expression of neurotrophic factors such as nerve growth factor (NGF), ciliary neurotrophic factor (CNTF), and glial cell line-derived neurotrophic factor (GDNF). Because these neurotrophic factors modulate secondary trophic factor expression in Müller glial cells, microglia-Müller glia cell interaction may contribute to protection of photoreceptors or increase photoreceptor apoptosis. In the present study, we demonstrate the possibility that such functional glia-glia interactions constitute the key mechanism by which microglia-derived NGF, brain-derived neurotrophic factor (BDNF), and CNTF indirectly influence photoreceptor survival, although the receptors for these neurotrophic factors are absent from photoreceptors, by modulating basic fibroblast growth factor (bFGF) and GDNF production and release from Müller glia. These observations suggest that microglia regulate the microglia-Müller glia-photoreceptor network that serves as a trophic factor-controlling system during retinal degeneration.
Insights
Microglia interact with Müller glial cells to control neurotrophic factors, influencing photoreceptor survival during retinal degeneration. This glia-glia communication network is crucial for managing trophic support in the retina.
Area of Science:
- Neuroscience
- Ophthalmology
- Cell Biology
Background:
- Microglia activation is a common response to CNS pathology.
- Light-induced retinal degeneration causes photoreceptor apoptosis.
- Activated microglia alter neurotrophic factor expression in the retina.
Purpose of the Study:
- To investigate the role of microglia-Müller glia interactions in photoreceptor survival.
- To elucidate the mechanism of microglia-derived neurotrophic factors influencing photoreceptor cells.
- To understand the trophic factor-controlling system in retinal degeneration.
Main Methods:
- Analysis of activated microglia in light-reared retinas.
- Assessment of neurotrophic factor expression (NGF, CNTF, GDNF).
- Investigation of microglia-Müller glia cell interactions and their impact on photoreceptor survival.
Main Results:
- Activated microglia invade the degenerating photoreceptor layer.
- Microglia alter expression of NGF, CNTF, and GDNF.
- Microglia-derived neurotrophic factors indirectly influence photoreceptor survival by modulating Müller glia production of bFGF and GDNF.
Conclusions:
- Microglia-Müller glia interactions form a key mechanism regulating trophic support in the retina.
- This glia-glia network modulates neurotrophic factor release, impacting photoreceptor survival.
- Microglia play a critical role in the microglia-Müller glia-photoreceptor network during retinal degeneration.