Article

Sex steroids control neuroinflammatory processes in the brain: relevance for acute ischaemia and degenerative demyelination.

Institute of Neuroanatomy, RWTH Aachen University, Aachen, Germany.
Journal of Neuroendocrinology (impact factor: 3.14). 05/2011; 24(1):62-70. DOI:10.1111/j.1365-2826.2011.02163.x pp.62-70
Source: PubMed

ABSTRACT Sex steroids have been demonstrated as powerful compounds to protect neurones and neural tissue from neurotoxic challenges and during neurodegeneration. A multitude of cellular actions have been attributed to female gonadal steroid hormones, including the regulation of pro-survival and anti-apoptotic factors, bioenergetic demands and radical elimination, growth factor allocation and counteracting against excitotoxicity. In recent years, immune-modulatory and anti-inflammatory characteristics of oestrogen and progesterone have also come under scrutiny. To date, each of these physiological responses has been considered to be partially and selectively integrated in the mediation of steroid-mediated cell protection and tested in suitable animal models and in vitro systems. To what extent these individual effects contribute to the overall neural protection remains sketchy. One idea is that a battery of cellular mechanisms operates at the same time. On the other hand, interactions and the control of the brain-intrinsic and peripheral immune system may play an additional and perhaps pioneering function in this scenario, notwithstanding the importance of secondary adjuvant mechanisms. In the present review, we highlight neuroprotective effects of oestrogen and progesterone in two different disease models of the brain, namely acute ischaemic and demyelination damage, which represent the most common acute and degenerative neurological disorders in humans. Besides other inflammatory parameters, we discuss the idea that chemokine expression and signalling appear to be early hallmarks in both diseases and are positively affected by sex steroids. In addition, the complex interplay with local brain-resident immune-competent cells appears to be controlled by the steroid environment.

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    Article: Mild hypothermia attenuates mitochondrial oxidative stress by protecting respiratory enzymes and upregulating MnSOD in a pig model of cardiac arrest.
    Ping Gong, Chun-Sheng Li, Rong Hua, Hong Zhao, Zi-Ren Tang, Xue Mei, Ming-Yue Zhang, Juan Cui
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    PLoS ONE 01/2012; 7(4):e35313. · 4.09 Impact Factor
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Keywords

cellular actions
 
chemokine expression
 
complex interplay
 
degenerative neurological disorders
 
demyelination damage
 
different disease models
 
female gonadal steroid hormones
 
growth factor allocation
 
individual effects
 
local brain-resident immune-competent cells
 
neural tissue
 
neuroprotective effects
 
neurotoxic challenges
 
physiological responses
 
pioneering function
 
powerful compounds
 
present review
 
secondary adjuvant mechanisms
 
steroid-mediated cell protection
 
vitro systems
 

Katharina Berger