Damage to the bloodbrain barrier and activation of neuroinflammation by focal cerebral ischemia under hyperglycemic condition.
Int J Mol Med
; 48(1)2021 07.
Article
en En
| MEDLINE
| ID: mdl-34080644
ABSTRACT
Hyperglycemia aggravates brain damage caused by cerebral ischemia/reperfusion (I/R) and increases the permeability of the bloodbrain barrier (BBB). However, there are relatively few studies on morphological changes of the BBB. The present study aimed to investigate the effect of hyperglycemia on BBB morphological changes following cerebral I/R injury. Streptozotocininduced hyperglycemic and citratebuffered salineinjected normoglycemic rats were subjected to 30 min middle cerebral artery occlusion. Neurological deficits were evaluated. Brain infarct volume was assessed by 2,3,5triphenyltetrazolium chloride staining and BBB integrity was evaluated by Evans blue and IgG extravasation following 24 h reperfusion. Changes in tight junctions (TJ) and basement membrane (BM) proteins (claudin, occludin and zonula occludens1) were examined using immunohistochemistry and western blotting. Astrocytes, microglial cells and neutrophils were labeled with specific antibodies for immunohistochemistry after 1, 3 and 7 days of reperfusion. Hyperglycemia increased extravasations of Evan's blue and IgG and aggravated damage to TJ and BM proteins following I/R injury. Furthermore, hyperglycemia suppressed astrocyte activation and damaged astrocytic endfeet surrounding cerebral blood vessels following I/R. Hyperglycemia inhibited microglia activation and proliferation and increased neutrophil infiltration in the brain. It was concluded that hyperglycemiainduced BBB leakage following I/R might be caused by damage to TJ and BM proteins and astrocytic endfeet. Furthermore, suppression of microglial cells and increased neutrophil infiltration to the brain may contribute to the detrimental effects of preischemic hyperglycemia on the outcome of cerebral ischemic stroke.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Membrana Basal
/
Barrera Hematoencefálica
/
Isquemia Encefálica
/
Uniones Estrechas
/
Hiperglucemia
Límite:
Animals
Idioma:
En
Revista:
Int J Mol Med
Asunto de la revista:
BIOLOGIA MOLECULAR
/
GENETICA MEDICA
Año:
2021
Tipo del documento:
Article