Brain-Derived Glia Maturation Factor β Participates in Lung Injury Induced by Acute Cerebral Ischemia by Increasing ROS in Endothelial Cells / 神经科学通报·英文版

Brain damage can cause lung injury. To explore the mechanism underlying the lung injury induced by acute cerebral ischemia (ACI), we established a middle cerebral artery occlusion (MCAO) model in male Sprague-Dawley rats. We focused on glia maturation factor β (GMFB) based on quantitative analysis of the global rat serum proteome. Polymerase chain reaction, western blotting, and immunofluorescence revealed that GMFB was over-expressed in astrocytes in the brains of rats subjected to MCAO. We cultured rat primary astrocytes and confirmed that GMFB was also up-regulated in primary astrocytes after oxygen-glucose deprivation (OGD). We subjected the primary astrocytes to Gmfb RNA interference before OGD and collected the conditioned medium (CM) after OGD. We then used the CM to culture pulmonary microvascular endothelial cells (PMVECs) acquired in advance and assessed their status. The viability of the PMVECs improved significantly when Gmfb was blocked. Moreover, ELISA assays revealed an elevation in GMFB concentration in the medium after OGD. Cell cultures containing recombinant GMFB showed increased levels of reactive oxygen species and a deterioration in the state of the cells. In conclusion, GMFB is up-regulated in astrocytes after ACI, and brain-derived GMFB damages PMVECs by increasing reactive oxygen species. GMFB might thus be an initiator of the lung injury induced by ACI.

Effect of Herba Lycopodii Alcohol Extracted Granule Combined Methylprednisolone on Expression Levels of BDNF and NMDA and Behavior of Traumatic Spinal Cord Injury Rats / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To study different effects of Herba Lycopodii (HL) Alcohol Extracted Granule combined methylprednisolone on behavioral changes, brain derived neurotrophic factor (BDNF) expression levels, and N-methyl-D-aspartate (NMDA) receptor levels in rats with spinal cord injury (SCI).</p><p><b>METHODS</b>Male adult SD rats were randomly divided into five groups, i.e., the sham-operation group, the model group, the HL treatment group, the methylprednisolone treatment group, the HL + methylprednisolone treatment group. Rats in the HL treatment group were intragastrically administered with HL at the daily dose of 50 mg/kg for 5 successive days. Rats in the methylprednisolone treatment group were intramuscularly injected with 50 mg/kg methylprednisolone within 8 h after spinal cord contusion, and then the dose of methylprednisolone was reduced for 10 mg/kg for 5 successive days. Rats in the HL + methylprednisolone treatment group received the two methods used for the aforesaid two groups. Basso Beattie and Bresnahan (BBB) score (for hindlimb motor functions) were assessed at day 0, 3, 7, and 28 after operation. At day 13 after SCI, injured spinal T8-10 was taken from 8 rats of each group and stored in liquid nitrogen. The N-methyl-D-aspartate (NMDA) receptor affinity (Kd) and the maximal binding capacity (Bmax) were determined using [3H]MK-801 radioactive ligand assay. Rats' injured spinal cords were taken for immunohistochemical assay at day 28 after SCI. Expression levels of BDNF in the ventral and dorsal horn of the spinal cord were observed.</p><p><b>RESULTS</b>Compared with the sham-operation group, the number of BDNF positive neurons in the ventral and dorsal horn of the spinal cord increased in the model group, Bmax increased (470 ± 34), Kd decreased, and BBB scores decreased at day 3 -28 (all P <0. 05). Compared with the SCI model group, the number of BDNF positive neurons and Kd increased, BBB scores at day 3 -28 increased (P <0. 05) in each medicated group. Bmax was (660 ± 15) in the methylprednisolone treatment group, (646 ± 25) in the HL treatment group, and (510 ± 21) in the HL +methylprednisolone treatment group (P <0. 05). Compared with the methylprednisolone treatment group, the number of BDNF positive neurons and Kd increased, BBB scores at day 7 -28 increased, and Bmax decreased in the HL treatment group and the HL + methylprednisolone treatment group (all P <0. 05). Compard with the HL treatment group, the number of BDNF positive neurons and Kd increased, and Bmax decreased (all P < 0.05).</p><p><b>CONCLUSIONS</b>HL could effectively improve motor functions of handlimbs, increase expression levels of BDNF in the spinal cord, and lessen secondary injury by affecting spinal levels of NMDA receptors. It showed certain therapeutic and protective roles in treating SCI. Its effect was better than that of methylprednisolone with synergism.</p>

Changes in glial fibrillary acidic protein and growth-associated protein-43 expressions in retinal ganglial cells during axonal regeneration / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the changes in the expressions of glial fibrillary acidic protein (GFAP) and growth- associated protein-43 (GAP-43) in retinal ganglial cells after neural transplantation.</p><p><b>METHODS</b>Thirty-nine rats were randomized into normal control group, nerve amputation group and nerve amputation with peripheral nerve transplantation group. Immunohistochemistry was used to detect the changes in the expressions of GFAP and GAP-43 at different time points after the operations, and real-time PCR was employed to detect the mRNA expressions of 13 genes in the retinal ganglial cells of the rats.</p><p><b>RESULTS</b>Immunohistochemistry showed obviously increased GFAP expressions in the retina following the nerve amputation. GFAP expression was down-regulated while GAP-43 expression upregulated in the retinal ganglial cells after peripheral nerve transplantation. Real-time PCR results showed that 5 days after the operations, retinal GFAP and GAP-43 expressions increased significantly in the nerve amputation group and peripheral nerve transplantation groups as compared with those in the control group, but GAP-43 expression decreased significantly in the former two groups afterwards.</p><p><b>CONCLUSION</b>The regenerated retina may adjust the production of GFAP. The retinal ganglial cells express GAP-43 during retinal regeneration. Up-regulation of the expression of GAP-43 provides the evidence for nerve regeneration following the nerve transplantation.</p>

Kallikrein-binding protein promotes axonal regeneration and protect rat retinal ganglion cells following optic nerve injury / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the effect of kallikrein-binding protein (KPB) in protecting retinal ganglion cells (RGCs) and promoting axonal regeneration following optical nerve injury in rats.</p><p><b>METHODS</b>Crush injury of the optic nerve at 0.5-1.0 mm from the eyeball was induced in rats, which received subsequent KBP injection into the vitreous cavity (experimental group) and PBS injection (control group). At 7, 14 and 21 days after the injury, the rats were sacrificed and frozen sections of the eyeball were prepared to observe the structure and thickness of the retina and count the number of survival RGCs with HE staining. The optic nerves were collected for Western blotting to assess the effect of KBP on the RGCs and axonal regeneration.</p><p><b>RESULTS</b>RGC counts and retinal thickness showed significant differences between the two groups. Western blotting also demonstrated a significant difference in the expression of the nerve regeneration marker protein GAP-43 between the two groups.</p><p><b>CONCLUSION</b>KBP offers protection on RGCs and promotes regeneration of the optic nerve axons after optic nerve injury in rats.</p>

Role of phospholipase C-gamma1 signaling pathway in H(2)O(2)-induced apoptosis of PC12 cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the role of phospholipase C-gamma1 (PLC-gamma1) signaling pathway in H(2)O(2)-induced apoptosis of PC12 cells.</p><p><b>METHODS</b>PC12 cells were exposed to 50 micromol/L H(2)O(2) after pretreatment with 10 micromol/L U73122, a specific PLC-gamma1 inhibitor. Hoechst/PI double staining was performed to observe the morphological changes of the cells under light microscope. MTT assay was used to evaluate the cell viability, and the percentage of apoptotic cells was analyzed by flow cytometry. DNA fragmentation assay was carried out to characterize the cell apoptosis.</p><p><b>RESULTS</b>After inhibition of the PLC-gamma1 signaling pathway with 10 micromol/L U73122, PC12 cells showed obvious apoptotic morphology, the viable cells decreased significantly, and the percentage of apoptotic cells rose to 35.7%. PC12 cells treated with U73122 presented with a distinct DNA ladder on electrophoresis resulting from DNA cleavage in the apoptotic cells.</p><p><b>CONCLUSION</b>PLC-gamma1 signaling pathway plays an important protective role in H(2)O(2)-induced PC12 cell apoptosis.</p>