Inhibitory effect of icariin on expression of myelin inhibitory factors in the central nervous system of rats with focal cerebral ischemia

Icariin, the major active component of Chinese medicinal herb epimedium brevicornum maxim, is used widely in traditional Chinese medicine for the treatment of neurological diseases. However, the effects of icariin on myelin inhibitory factors are as yet unclear. In the present study, administration of icariin at 20 mg/kg showed a marked reduction in neurological deficit of middle cerebral artery occlusion rats. Icariin exhibited better inhibitory effects on myelin inhibitory factors： Nogo-A, myelin-associated glycoprotein and oligodendrocyte myelin glycoprotein in ischemia regions of middle cerebral artery occlusion rats compared with monosialotetrahexosylganglioside. These results indicate that icariin exhibits potent inhibitory effects on expression of myelin inhibitors after middle cerebral artery occlusion-induced focal cerebral ischemia in vivo. This effect may be mediated, at least in part, by the inhibition of both Nogo-A, myelin-associated glycopretein and oligodendrocyte myelin glycoprotein activation, followed by the enhancement of axonal sprouting and regeneration, resulting in neurological functional recovery.

Transcriptome Sequencing Reveals Astrocytes as a Therapeutic Target in Heat-Stroke

Heat-stroke is a serious form of hyperthermia with high mortality, and can induce severe central nervous system disorders. The neurovascular unit（NVU）, which consists of vascular cells, glial cells, and neurons, controls blood-brain barrier（BBB） permeability and cerebral blood flow, and maintains the proper functioning of neuronal circuits. However, the detailed function of each BBB component in heat-stroke remains unknown. In order to interpret alterations caused by heat stress, we performed transcriptome comparison of neuron and astrocyte primary cultures after heat treatment. Differentially-expressed genes were then selected and underwent Gene Ontology annotation and Kyoto Encyclopedia of Genes and Genomes pathway analysis. Gene-act networks were also constructed, and the expression of pivotal genes was validated by quantitative PCR, as well as single-cell q PCR in heatstroke rats. Our work provides valuable information on the transcriptional changes in NVU cells after heat stress,reveals the diverse regulatory mechanisms of two of these cellular components, and shows that a cell-type-specificapproach may be a promising therapeutic strategy for heatstroke treatments.