[Expression of proteins in serum and hippocampus after closed brain injury in rats].

OBJECTIVE: To explore the difference of expression of proteins between the serum and hippocampus after brain injury in rats. METHODS: Male SD rats were used to establish brain injury model. The changes of proteins expression profile in serum and hippocampus at different time after brain injury were analyzed using weak cationic exchanger (WCX2) chips and immobilized metal affinity capture arrays-Cu (IMAC-Cu) chips by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry. RESULTS: A total of 436 protein peaks were detected in serum and 346 protein peaks were detected in hippocampus using WCX2 chips. A total of 229 protein peaks were detected in serum and 345 protein peaks were detected in hippocampus using IMAC-Cu chips. The same 10 protein peaks were respectively detected in serum and hippocampus using WCX2 chips. The same 13 protein peaks were respectively detected in serum and hippocampus using IMAC-Cu chips. CONCLUSION: The changes of protein expression profile in serum and hippocampus are obvious after closed brain injury and show a significant difference. The different proteins detected in serum and hippocampus using the same chip could be biochemical markers for determining brain injury.

[Proteomic changes in cerebral cortex of neonatal rats with experimental congenital hypothyroidism].

OBJECTIVE: To screen differentially expressed brain proteins with proteomic method in cerebral cortex of neonatal rats with congenital hypothyroidism. METHOD: From the 13th day of gestation, pregnant Wistar rats from the experimental group were given intragastrically with 2.5 ml of 1% propylthiouracil daily. Cerebral cortex specimens were collected from the control and hypothyroidism neonatal rats. Two-directional electrophoresis (2-DE) was applied to analyze protein expression diversities between the euthyroid and hypothyroidism neonatal rat cerebral cortex. Protein spots with significantly different expression were screened and identified by mass spectrometry. Radioimmunoassay (RIA) was used to analyze serum FT(3), FT(4) levels of each groups. RESULT: The body weight of hypothyroid neonatal rats were lower than those in the corresponding control group (t = -8.07, P < 0.01). The FT(3) levels of hypothyroid neonatal rats were lower than those in the corresponding control group (t = 5.39, P < 0.01). The FT(4) levels of hypothyroid neonatal rats were lower than those in the corresponding control group (t = 7.62, P < 0.01). Stable 2-DE maps of normal and CH neonatal rat were constantly obtained. The maps were analyzed by software. Seven protein spots with high reproducibility, high resolution and significantly different expression were chosen and identified by mass spectrometry, including collapsing response mediator protein 2, actin related protein 2/3 complex subunit 5, ubiquitin-conjugating enzyme E2-25K, ATP synthase subunit d, Cu-Zn superoxide dismutase, synuclein alpha, and nucleoside diphosphate kinase. CONCLUSION: The value of this research is demonstrated here by the identification of several proteins known to be associated with nerve synapse structures formation, cell survival, metabolism, cell signal transduction, neural differentiation and nerve growth in the central nervous system. Furthermore this study identified several proteins except for collapsing response mediator protein 2 and Cu-Zn superoxide dismutase that have not previously been described in the literature and which may play an important role as either sensitive biomarkers of brain dysfunction caused by congenital hypothyroidism. In congenital hypothyroidism, brain development retardation may be related with some important processes, including abnormal synaptic formation, excess ROS production and apoptosis. The above-mentioned proteins may play critical roles in the processes, which provide valuable clues to clarify the pathogenesis of brain developmental disorders induced by congenital hypothyroidism.

[The study in primary cultured astrocytes following fluid percussion injury].

OBJECTIVE: To investigate the morphology alterations and proteomics changes in primary astrocytes following fluid percussion injury. METHODS: Primary cultures of astrocytes were prepared from cerebral hemispheres of 1-3 d-old SD rats, then, astrocytes were randomly divided into control group and injury group which were subjected to (0.2 +/- 0.01) MPa fluid percussion injury. The changes of protein expression pattern in astrocytes between injury and control groups were monitored with two dimensional gel electrophoresis. RESULTS: Astrocytes' s abnonmalities of morphology after injury were apparent. The fluid percussion injury caused astrocytes edema, shrinkage, cell junction disconnection and necrosis at 2 h after injury. 24 h and 48 h after injury, most part of astrocytes's dendrites and soma became hypertrophy and showed a higher rate of cell proliferation. The dynamic proteomics changes were identified and total different 13 spots were detected in this study from the 2DE gels. The different displayed 5 spots were identified via MALDI-TOF: cofilin 1, destrin, phosphoglycerate mutase 1, NADH dehydrogenase (ubiquinone) 1 alpha subcomplex 10, annexin 1. CONCLUSION: The obvious alteration of morphology and protein expression pattern in primary cultured astrocytes could be induced after fluid percussion injury. The differential proteins detected were probably related to stress responses.

[Detection of differential proteins in white matter in brain injury in rat by using a WCX-2 protein chip].

OBJECTIVE: To study the alteration in cortex protein fingerprinting of cerebral cortex after closed brain injury in rat. METHODS: Seventy-two male Sprague-Dawley (SD) rats were randomly divided into sham operation group, 4, 8, 12, 24 and 48 hours postinjury groups. Eight rats in each group were used for WCX-2 protein chip research, and 4 rats in each group for pathological examination. Marmarou's weight-dropping model was reproduced, and brain cortex was harvested for study with hematoxylin-eosin (HE) staining, and Bradford method was adopted for WCX-2 protein chip research, and protein chip reading was obtained for protein fingerprinting analysis. RESULTS: (1) The pathological observation showed different degree of injury could be seen in all the injury groups. (2) The WCX-2 experiment found that 3 protein expressions had changed in cortex after brain injury compared with the sham operation group. The differential protein with molecular weight of 5,639 protein expression was found to be upregulated at 8 hours after injury (P<0.05). The 3,212 protein did not expressed in sham operation or 4, 8, 12 and 24 hours groups, but upregulated at 48 hours after injury (P<0.05). The expression of 7,536 protein was upregulated at 24 hours after injury (P<0.05), but not in sham operation or 4, 8, 12, and 48 hours groups. CONCLUSION: Alterations in protein expression in cerebral cortex could be induced after brain injury.