Heat Shock Protein 27 Injection Leads to Caspase Activation in the Visual Pathway and Retinal T-Cell Response.
Pia GrotegutPhilipp Johannes HoerdemannSabrina ReinehrNupur GuptaH Burkhard DickStephanie Christine JoachimPublished in: International journal of molecular sciences (2021)
Heat shock protein 27 (HSP27) is one of the small molecular chaperones and is involved in many cell mechanisms. Besides the known protective and helpful functions of intracellular HSP27, very little is known about the mode of action of extracellular HSP27. In a previous study, we showed that intravitreal injection of HSP27 led to neuronal damage in the retina and optic nerve after 21 days. However, it was not clear which degenerative signaling pathways were induced by the injection. For this reason, the pathological mechanisms of intravitreal HSP27 injection after 14 days were investigated. Histological and RT-qPCR analyses revealed an increase in endogenous HSP27 in the retina and an activation of components of the intrinsic and extrinsic apoptosis pathway. In addition, an increase in nucleus factor-kappa-light-chain-enhancer of activated B cells (NFκB), as well as of microglia/macrophages and T-cells could be observed. In the optic nerve, however, only an increased apoptosis rate was detectable. Therefore, the activation of caspases and the induction of an incipient immune response seem to be the main triggers for retinal degeneration in this intravitreal HSP27 model.
Keyphrases
- heat shock protein
- optic nerve
- heat shock
- diabetic retinopathy
- optical coherence tomography
- oxidative stress
- immune response
- signaling pathway
- cell death
- ultrasound guided
- nuclear factor
- endoplasmic reticulum stress
- single cell
- cell cycle arrest
- binding protein
- toll like receptor
- spinal cord injury
- dendritic cells
- single molecule
- lps induced
- brain injury
- mesenchymal stem cells
- endothelial cells
- atomic force microscopy
- reactive oxygen species
- mass spectrometry
- high speed