Brain can acquire tolerance to a lethal insult if exposed to a previous sublethal stimulus. This phenomenon is called Preconditioning and works inducing both a rapid and a delayed response based on changes of gene expression regulation. In order to understand the molecular mechanisms underlying the Preconditioning phenomenon, we carried out epigenetic analysis on rat brains exposed to a stimulus able to trigger Preconditioning-dependent neuroprotection. The results of our study lead us to hypothesize that epigenetic control of gene expression has a pivotal role in the Preconditioning-dependent neuroprotection by establishing a molecular memory of transcribed neuroprotective genes and increasing genome stability via the silencing of retrotransposon sequences. Currently, we are developing an in vitro model system of Preconditioning with the aim to specifically focus the epigenetic analysis on neuronal cells. To this scope, we used a human neuroblastoma cell line (SHSY5Y) differentiated into cells with a more mature and neuron-like phenotype by means of retinoic acid and BDNF. In order to trigger the Preconditioning, we used a depolarization protocol based on the addition of 100 mM KCl to the cellular medium. First of all, we validated the Preconditioning-dependent neuroprotection in our model system by showing that depolarized cells have higher survival rate than non-depolarized control cells after H202 treatment. The expression analysis of different genes showed that depolarized cells are able to more quickly increase the level of some neuroprotective transcripts than control cells. These results are in line with the hypothesis that preconditioned cells establish an epigenetic state that allows a faster gene response in case of insult. To corroborate such hypothesis, we also investigated the chromatin modifications induced by depolarization at level of the promoter of specific neuroprotective genes.
Preconditioning-dependent neuroprotection: epigenetic mechanism underlying this phenomenon in an in vitro cellular system / Drongitis, Denise; Cerbone, Stefania; Fucci, Laura; Donizetti, Aldo. - (2016). (Intervento presentato al convegno Frontiers in Molecular Biology: From Single Cell Analysis to Precision Medicine).
Preconditioning-dependent neuroprotection: epigenetic mechanism underlying this phenomenon in an in vitro cellular system
DRONGITIS, DENISE;FUCCI, LAURA;DONIZETTI, ALDO
2016
Abstract
Brain can acquire tolerance to a lethal insult if exposed to a previous sublethal stimulus. This phenomenon is called Preconditioning and works inducing both a rapid and a delayed response based on changes of gene expression regulation. In order to understand the molecular mechanisms underlying the Preconditioning phenomenon, we carried out epigenetic analysis on rat brains exposed to a stimulus able to trigger Preconditioning-dependent neuroprotection. The results of our study lead us to hypothesize that epigenetic control of gene expression has a pivotal role in the Preconditioning-dependent neuroprotection by establishing a molecular memory of transcribed neuroprotective genes and increasing genome stability via the silencing of retrotransposon sequences. Currently, we are developing an in vitro model system of Preconditioning with the aim to specifically focus the epigenetic analysis on neuronal cells. To this scope, we used a human neuroblastoma cell line (SHSY5Y) differentiated into cells with a more mature and neuron-like phenotype by means of retinoic acid and BDNF. In order to trigger the Preconditioning, we used a depolarization protocol based on the addition of 100 mM KCl to the cellular medium. First of all, we validated the Preconditioning-dependent neuroprotection in our model system by showing that depolarized cells have higher survival rate than non-depolarized control cells after H202 treatment. The expression analysis of different genes showed that depolarized cells are able to more quickly increase the level of some neuroprotective transcripts than control cells. These results are in line with the hypothesis that preconditioned cells establish an epigenetic state that allows a faster gene response in case of insult. To corroborate such hypothesis, we also investigated the chromatin modifications induced by depolarization at level of the promoter of specific neuroprotective genes.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
