Human alpha 1-antitrypsin protects neurons and glial cells against oxygen and glucose deprivation through inhibition of interleukins expression

Background

Death due to cerebral stroke afflicts a large number of neuronal populations, including glial cells depending on the brain region affected. Drugs with a wide cellular range of protection are needed to develop effective therapies for stroke. Human alpha 1-antitrypsin (hAAT) is a serine proteinase inhibitor with potent anti-inflammatory, anti-apoptotic and immunoregulatory activities. This study aimed to test whether hAAT can protect different kind of neurons and glial cells after the oxygen and glucose deprivation (OGD).

Methods

Addition of hAAT to mouse neuronal cortical, hippocampal and striatal cultures, as well as glial cultures, was performed 30?min after OGD induction and cell viability was assessed 24?h later. The expression of different apoptotic markers and several inflammatory parameters were assessed by immunoblotting and RT-PCR.

Results

hAAT had a concentration-dependent survival effect in all neuronal cultures exposed to OGD, with a maximal effect at 1–2?mg/mL. The addition of hAAT at 1?mg/mL reduced the OGD-mediated necrotic and apoptotic death in all neuronal cultures. This neuroprotective activity of hAAT was associated with a decrease of cleaved caspase-3 and an increase of MAP2 levels. It was also associated with a reduction of pro-inflammatory cytokines protein levels and expression, increase of IL-10 protein levels and decrease of nuclear localization of nuclear factor-kappaB. Similar to neurons, addition of hAAT protected astrocytes and oligodendrocytes against OGD-induced cell death.

Conclusions

Human AAT protects neuronal and glial cells against OGD through interaction with cytokines.

General significance

Human AAT could be a good therapeutic neuroprotective candidate to treat ischemic stroke.