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Updated: May 28, 2026
Molecular Modulation by Lentivirus-Delivered Specific shRNAs in Endoplasmic Reticulum Stressed Neurons
Published on: April 24, 2021
Dendrimer-mediated siRNA delivery knocks down Beclin 1 and potentiates NMDA-mediated toxicity in rat cortical neurons
María D Pérez-Carrión1, Francisco C Pérez-Martínez, Sonia Merino
1NanoDrugs, S.L. Parque Científico y Tecnológico, Albacete, Spain.
Abstract:
Autophagy is an important process which plays a key role in cellular homeostasis by degrading cytoplasmic components in the lysosomes, which facilitates recycling. Alterations to normal autophagy have been linked to excitotoxicity, but the mechanisms governing its signal transduction remain unclear. The aim of this study was to explore the role of autophagy in neuronal excitotoxic death by delivering small interfering RNA (siRNA) to rat cortical neurons, using a dendrimer to silence the autophagy-related gene 6 (beclin 1) and to determine the role of autophagy in excitotoxicity. We have found that the dendrimer is very efficient to deliver siRNA to rat cortical neurons, leading to almost complete removal of the target protein Beclin 1. In addition, NMDA increases autophagy markers, such as the protein levels of Beclin 1, the microtubule-associated light chain 3 (LC3) B-II/LC3B-I ratio, and monodansylcadaverine (MDC) labeling in rat cortical neurons. Moreover, NMDA also increases the formation of autophagosomes observed under a transmission electron microscope. Silencing beclin 1 expression blocked NMDA-induced autophagy. Moreover, Beclin 1 removal potentiated NMDA-induced neuronal death indicating that autophagy plays a protective role during excitotoxicity and suggesting that targeting autophagy might be a helpful therapeutic strategy in neurodegenerative diseases.
Insights
Autophagy, a cellular recycling process, protects neurons from excitotoxic death. Silencing beclin 1, a key autophagy gene, worsened NMDA-induced neuronal death, highlighting autophagy's protective role.
Area of Science:
- Neuroscience
- Cell Biology
- Molecular Biology
Background:
- Autophagy is crucial for cellular homeostasis and recycling.
- Dysfunctional autophagy is implicated in neurodegenerative diseases and excitotoxicity.
- The precise role of autophagy in excitotoxic neuronal death remains unclear.
Purpose of the Study:
- To investigate the role of autophagy in excitotoxic neuronal death.
- To determine if autophagy activation is protective or detrimental during excitotoxicity.
- To assess the feasibility of targeting autophagy for neuroprotection.
Main Methods:
- Utilized dendrimer-mediated delivery of small interfering RNA (siRNA) to silence beclin 1 in rat cortical neurons.
- Quantified autophagy markers including Beclin 1, LC3B-II/LC3B-I ratio, and monodansylcadaverine (MDC) labeling.
- Assessed neuronal death following NMDA stimulation in both control and beclin 1-silenced neurons.
- Confirmed autophagosome formation using transmission electron microscopy.
Main Results:
- Dendrimer-mediated siRNA efficiently silenced beclin 1 expression in rat cortical neurons.
- NMDA stimulation increased autophagy markers and autophagosome formation.
- Silencing beclin 1 inhibited NMDA-induced autophagy.
- Beclin 1 knockdown potentiated NMDA-induced neuronal death.
Conclusions:
- Autophagy plays a significant protective role in mitigating excitotoxic neuronal death.
- NMDA receptor activation triggers an autophagic response in neurons.
- Targeting autophagy pathways may represent a promising therapeutic strategy for neurodegenerative diseases involving excitotoxicity.
