Repression of the Glucocorticoid Receptor Aggravates Acute Ischemic Brain Injuries in Adult Mice

Yong Li, The Lawrence D. Longo, MD Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University, School of Medicine, Loma Linda, CA 92350, USA.Follow
Lei Huang, The Lawrence D. Longo, MD Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University, School of Medicine, Loma Linda, CA 92350, USA.Follow
Qingyi Ma, The Lawrence D. Longo, MD Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University, School of Medicine, Loma Linda, CA 92350, USA.Follow
Katherine R. Concepcion, The Lawrence D. Longo, MD Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University, School of Medicine, Loma Linda, CA 92350, USA.Follow
Minwoo A. Song, The Lawrence D. Longo, MD Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University, School of Medicine, Loma Linda, CA 92350, USA.Follow
Peng Zhang, The Lawrence D. Longo, MD Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University, School of Medicine, Loma Linda, CA 92350, USA.Follow
Yingjie Fu, The Lawrence D. Longo, MD Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University, School of Medicine, Loma Linda, CA 92350, USA.Follow
Daliao Xiao, The Lawrence D. Longo, MD Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University, School of Medicine, Loma Linda, CA 92350, USA.Follow
Lubo Zhang, The Lawrence D. Longo, MD Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University, School of Medicine, Loma Linda, CA 92350, USA.Follow

Document Type

Article

Publication Date

8-17-2018

Publication Title

International journal of molecular sciences

E-ISSN

1422-0067

Abstract

Strokes are one of the leading causes of mortality and chronic morbidity in the world, yet with only limited successful interventions available at present. Our previous studies revealed the potential role of the glucocorticoid receptor (GR) in the pathogenesis of neonatal hypoxic-ischemic encephalopathy (HIE). In the present study, we investigate the effect of GR knockdown on acute ischemic brain injuries in a model of focal cerebral ischemia induced by middle cerebral artery occlusion (MCAO) in adult male CD1 mice. GR siRNAs and the negative control were administered via intracerebroventricular (i.c.v.) injection 48 h prior to MCAO. The cerebral infarction volume and neurobehavioral deficits were determined 48 h after MCAO. RT-qPCR was employed to assess the inflammation-related gene expression profiles in the brain before and after MCAO. Western Blotting was used to evaluate the expression levels of GR, the mineralocorticoid receptor (MR) and the brain-derived neurotrophic factor/tropomyosin receptor kinase B (BDNF/TrkB) signaling. The siRNAs treatment decreased GR, but not MR, protein expression, and significantly enhanced expression levels of pro-inflammatory cytokines (IL-6, IL-1β, and TNF-α) in the brain. Of interest, GR knockdown suppressed BDNF/TrkB signaling in adult mice brains. Importantly, GR siRNA pretreatment significantly increased the infarction size and exacerbated the neurobehavioral deficits induced by MCAO in comparison to the control group. Thus, the present study demonstrates the important role of GR in the regulation of the inflammatory responses and neurotrophic BDNF/TrkB signaling pathway in acute ischemic brain injuries in adult mice, revealing a new insight into the pathogenesis and therapeutic potential in acute ischemic strokes.

Volume

19

Issue

8

DOI

10.3390/ijms19082428

PubMed ID

30126083

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