Dysregulation of BDNF/TrkB signaling mediated by NMDAR/Ca2+/calpain might contribute to postoperative cognitive dysfunction in aging mice.
J Neuroinflammation
; 17(1): 23, 2020 Jan 16.
Article
em En
| MEDLINE
| ID: mdl-31948437
ABSTRACT
BACKGROUND:
Postoperative cognitive decline (POCD) is a recognized clinical phenomenon characterized by cognitive impairments in patients following anesthesia and surgery, yet its underlying mechanism remains unclear. Brain-derived neurotrophic factor (BDNF) plays an important role in neuronal plasticity, learning, and memory via activation of TrkB-full length (TrkB-FL) receptors. It has been reported that an abnormal truncation of TrkB mediated by calpain results in dysregulation of BDNF/TrkB signaling and is associated with cognitive impairments in several neurodegenerative disorders. Calpains are Ca2+-dependent proteases, and overactivation of calpain is linked to neuronal death. Since one source of intracellular Ca2+ is N-methyl-d-aspartate receptors (NMDARs) related and the function of NMDARs can be regulated by neuroinflammation, we therefore hypothesized that dysregulation of BDNF/TrkB signaling mediated by NMDAR/Ca2+/calpain might be involved in the pathogenesis of POCD.METHODS:
In the present study, 16-month-old C57BL/6 mice were subjected to exploratory laparotomy with isoflurane anesthesia to establish the POCD animal model. For the interventional study, mice were treated with either NMDAR antagonist memantine or calpain inhibitor MDL-28170. Behavioral tests were performed by open field, Y maze, and fear conditioning tests from 5 to 8 days post-surgery. The levels of Iba-1, GFAP, interleukin-1ß (IL-1ß), IL-6, tumor necrosis factor-α (TNF-α), NMDARs, calpain, BDNF, TrkB, bax, bcl-2, caspase-3, and dendritic spine density were determined in the hippocampus.RESULTS:
Anesthesia and surgery-induced neuroinflammation overactivated NMDARs and then triggered overactivation of calpain, which subsequently led to the truncation of TrkB-FL, BDNF/TrkB signaling dysregulation, dendritic spine loss, and cell apoptosis, contributing to cognitive impairments in aging mice. These abnormities were prevented by memantine or MDL-28170 treatment.CONCLUSION:
Collectively, our study supports the notion that NMDAR/Ca2+/calpain is mechanistically involved in anesthesia and surgery-induced BDNF/TrkB signaling disruption and cognitive impairments in aging mice, which provides one possible therapeutic target for POCD.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Contexto em Saúde:
6_ODS3_enfermedades_notrasmisibles
Problema de saúde:
6_mental_health_behavioral_disorders
Assunto principal:
Envelhecimento
/
Transdução de Sinais
/
Complicações Cognitivas Pós-Operatórias
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
J Neuroinflammation
Assunto da revista:
NEUROLOGIA
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
China