Molecular changes underlying decay of sensory responses and enhanced seizure propensity in peritumoral neurons.
Neuro Oncol
; 25(8): 1463-1473, 2023 08 03.
Article
in En
| MEDLINE
| ID: mdl-36805257
ABSTRACT
BACKGROUND:
Glioblastoma growth impacts on the structure and physiology of peritumoral neuronal networks, altering the activity of pyramidal neurons which drives further tumor progression. It is therefore of paramount importance to identify glioma-induced changes in pyramidal neurons, since they represent a key therapeutic target.METHODS:
We longitudinal monitored visual evoked potentials after the orthotopic implant of murine glioma cells into the mouse occipital cortex. With laser microdissection, we analyzed layer II-III pyramidal neurons molecular profile and with local field potentials recordings we evaluated the propensity to seizures in glioma-bearing animals with respect to control mice.RESULTS:
We determine the time course of neuronal dysfunction of glioma-bearing mice and we identify a symptomatic stage, based on the decay of visual response. At that time point, we microdissect layer II-III pyramidal neurons and evaluate the expression of a panel of genes involved in synaptic transmission and neuronal excitability. Compared to the control group, peritumoral neurons show a decrease in the expression of the SNARE complex gene SNAP25 and the alpha1 subunit of the GABA-A receptor. No significant changes are detected in glutamatergic (ie, AMPA or NMDA receptor subunit) markers. Further reduction of GABA-A signaling by delivery of a benzodiazepine inverse agonist, DMCM (methyl-6,7-dimethoxy-4-ethyl-beta-carboline-3-carboxylate) precipitates seizures in 2 mouse models of tumor-bearing mice.CONCLUSIONS:
These studies reveal novel molecular changes that occur in the principal cells of the tumor-adjacent zone. These modifications may be therapeutically targeted to ameliorate patients' quality of life.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Evoked Potentials, Visual
/
Glioma
Aspects:
Patient_preference
Limits:
Animals
Language:
En
Journal:
Neuro Oncol
Journal subject:
NEOPLASIAS
/
NEUROLOGIA
Year:
2023
Document type:
Article
Affiliation country:
Italy