Neuroprotective Effect of Neuroserpin in Oxygen-Glucose Deprivation- and Reoxygenation-Treated Rat Astrocytes In Vitro

Abstract

Neuroserpin (NSP) reportedly exerts neuroprotective effects in cerebral ischemic animal models and patients; however, the mechanism of protection is poorly understood. We thus attempted to confirm neuroprotective effects of NSP on astrocytes in the ischemic state and then explored the relative mechanisms. Astrocytes from neonatal rats were treated with oxygen-glucose deprivation (OGD) followed by reoxygenation (OGD/R). To confirm the neuroprotective effects of NSP, we measured the cell survival rate, relative lactate dehydrogenase (LDH) release; we also performed morphological methods, namely Hoechst 33342 staining and Annexin V assay. To explore the potential mechanisms of NSP, the release of nitric oxide (NO) and TNF-α related to NSP administration were measured by enzyme-linked immunosorbent assay. The proteins related to the NF-κB, ERK1/2, and PI3K/Akt pathways were investigated by Western blotting. To verify the cause-and-effect relationship between neuroprotection and the NF-κB pathway, a NF-κB pathway inhibitor sc3060 was employed to observe the effects of NSP-induced neuroprotection. We found that NSP significantly increased the cell survival rate and reduced LDH release in OGD/R-treated astrocytes. It also reduced NO/TNF-α release. Western blotting showed that the protein levels of p-IKKBα/β and P65 were upregulated by the OGD/R treatment and such effects were significantly inhibited by NSP administration. The NSP-induced inhibition could be significantly reversed by administration of the NF-κB pathway inhibitor sc3060, whereas, expressions of p-ERK1, p-ERK2, and p-AKT were upregulated by the OGD/R treatment; however, their levels were unchanged by NSP administration. Our results thus verified the neuroprotective effects of NSP in ischemic astrocytes. The potential mechanisms include inhibition of the release of NO/TNF-α and repression of the NF-κB signaling pathways. Our data also indicated that NSP has little influence on the MAPK and PI3K/Akt pathways.

Neuroprotective Effects of Pycnogenol Against Oxygen-Glucose Deprivation/Reoxygenation-Induced Injury in Primary Rat Astrocytes via NF-κB and ERK1/2 MAPK Pathways

“…Previous research has shown that both a reduced rate of cell survival and an enhanced LDH release can be observed in OGD/R-treated astrocytes [30]. Astrocytes apoptosis may contribute to the pathogenesis of a number of acute and chronic neurodegenerative disorders, such as cerebral ischemia, Alzheimer’s disease and Parkinson’s disease [31].…”

“…It has been observed that the expression of p-ERK1, p-ERK2, p-IKKBα/β and P65 proteins is upregulated in OGD/R-treated rat astrocytes [30]. Previous scholars have found that this phytochemical PYC inhibits NF-κB activation in preventing the atherogenic process [33].…”

Neuroserpin Protects Rat Neurons and Microglia-Mediated Inflammatory Response Against Oxygen-Glucose Deprivation- and Reoxygenation Treatments in an In Vitro Study

“…The NSP-induced amelioration could be significantly reversed by the administration of sc3060, an NF-κB pathway inhibitor. Thus, we concluded that the inhibition of NF-κB signaling pathways may be a potential mechanism in the protective effects of NSP on astrocytes [11]. Neurons and microglia are the other important components in the brain.…”

“…The OGD/R processes were performed as previously described [11,22,23], with minor modifications. Briefly, the original glucose-containing media were removed from all treatment groups and kept aside for future use.…”

“…Because of the crucial roles of neurons and microglia in the CNS, the verification of neuroprotective effects of NSP on neurons and microglia-mediated inflammatory response is very important for clarifying the biological significance of NSP. On the basis of previous [10] and astrocytes [11] as part of a series of studies in our laboratory, the aim of the present study is to verify the neuroprotective effects of NSP on neurons and microglia-mediated inflammatory response. It has been reported that besides neurons, NSP linked to the differentiation and activation of the human myeloid lineage [16].…”