Neurochemical research
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Neurochemical research · Nov 2014
The role of SRC kinase in the caspase-1 pathway after hypoxia in the brain of newborn piglets.
Hypoxia induces a cerebral inflammatory response, which contributes to brain injury. Inflammasomes are complex intracellular molecular structures that initiate the inflammatory cascade. Caspase-1 and interleukin 1-β (IL-1β), have been established as markers of inflammasome activation. ⋯ We provide evidence that inhibition of Src kinase in the acute phase after hypoxia involves changes in the production or processing of caspase-1 subunits. Our data suggest that Src kinase mediates hypoxia-induced caspase-1 activation in the cerebral cortex of newborn piglets. Inhibition of Src kinase may attenuate the neuroinflammatory response and could represent a potential target for neuroprotection after hypoxic injury.
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Neurochemical research · Nov 2014
Progesterone attenuates aquaporin-4 expression in an astrocyte model of ischemia/reperfusion.
Previous studies have suggested that progesterone may be involved in neuroprotection by preventing brain edema. In this study, we assessed the effects of progesterone on aquaporin-4 (AQP4) expression in an ischemia/reperfusion model of cultured rat astrocytes, and further explored the possible role of the protein kinase C (PKC) pathway in this course. We evaluate primary culture astrocytes exposed to 4 h oxygen-glucose deprivation (OGD) followed by 24 h reperfusion (OGD4h/R24h) as a means of simulating cortex ischemia and reperfusion, and test the effect of progesterone on AQP4 expression in response to OGD4h/R24h. ⋯ At a concentration of 1 and 2 μM, progesterone significantly attenuated AQP4 at the level of both protein and mRNA and ameliorated the cell viability of astrocytes from OGD/reperfusion injury. Moreover, this effect was blocked by the PKC inhibitor Ro31-8220, which was employed before the OGD. These results indicate that progesterone exerts the protective effects and attenuates AQP4 expression in an astrocyte model of ischemia/reperfusion depending on the PKC signal pathway.
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Neurochemical research · Nov 2014
Attenuation of neuropathic pain by saikosaponin a in a rat model of chronic constriction injury.
Despite immense advances in the treatment strategies, the effective treatment of patients suffering from neuropathic pain remains challenging. Saikosaponin a possesses anti-inflammatory activity. However, the role of saikosaponin a in neuropathic pain is still unclear. ⋯ In addition, saikosaponin a inhibited CCI-induced the levels of TNF-α, IL-1β, IL-2 in spinal cord. Western blot analysis demonstrated that saikosaponin a reduced the elevated expression of p-p38 mitogen-activated protein kinase (MAPK) and NF-κB in the spinal cord induced by CCI. These results suggest that saikosaponin a could effectively attenuate neuropathic pain in CCI rats by inhibiting the activation of p38 MAPK and NF-κB signaling pathways in spinal cord.