Protection against inflammatory neurodegeneration and glial cell death by 7β-hydroxy epiandrosterone, a novel neurosteroid

Abstract

It has been demonstrated that neuroprotective effects of dehydroepiandrosterone (DHEA) may be mediated by its 7α- and 7β-hydroxy derivatives. Epiandrosterone is also converted to 7β-hydroxy epiandrosterone (7β-OH EPIA) in numerous tissues. The aim of the present study was to establish whether treatment with 7β-hydroxy epiandrosterone has a neuroprotective effect in animal models of Alzheimer's disease (AD) lesions. Intra-amygdaloid administration of amyloid β [Aβ(25–35)] increased the number of tau-positive cells in the ipsilateral hippocampus. Intracerebroventricular administration of ethylcholine aziridinium (AF64A) caused cholinergic damage in the septum, and glial lesions in the lateral septal nucleus and in the lateral zones of the hippocampus. These effects were almost completely prevented when animals were treated subcutaneously (b.i.d.) for 10 days with 0.1 mg/kg 7β-hydroxy epiandrosterone. These findings indicate that 7β-hydroxy epiandrosterone has powerful cytoprotective effects suggesting that (a) this neurosteroid may have therapeutic potential in various neurodegenerative conditions such as Alzheimer's disease, and (b) 7β-hydroxy steroids may constitute a novel class of endogenous neuroprotective agents.

Keywords

• Alzheimer's disease
• Animal model
• Aβ(25–35)
• AF64A
• 7β-hydroxy epiandrosterone
• Neurodegeneration