The Related Study Of Brain Glucose Metabolism And Neural Specificity Markers After Traumatic Brain Injury

PART ONESTUDY ON GLUCOSE METABOLISM AND THE INSEQUENTIAL EXPRESSION OF HYPOXIA INDUCIBLEFACTOR-1α AND GLUCOSE TRANSPORTER IN RATS’ BRAINCONTUSION AREA AFTER TRAUMATIC BRAIN INJURYObjectives:To detect the changes of the blood and extracellular cerebralfluid (ECF)glucose metabolism in rats brain contusion area duringthe acute stage after traumatic brain injury, simultaneous detect Hypoxiainducible Factor-1α(Hypoxia-inducible Factor-1,HIF-1α), glucosetransporter1(glucose transporter1,GLUT-1) and glucosetransporter3(glucose transporter3,GLUT-3) expression of local braincontusion cortex, analysis the sequential rule of these changes, in order toexplore the optimum time to control blood glucose after traumatic braininjury(TBI).Methods:35adult male SD rats were randomly divided into7groups, each group included normal control rat, traumatic brain injuryrats after TBI,5rats in each group. The glucose concentration of blood was measured at each time points after TBI15m、30m、45m、75m、90m、3h、6h、12h、24h、48h、72h, the dialysates of ECF in regional contusion of rat brainwere collected and analyzed for the content of glucose ([Glu]d) and lacticacid ([Lac]d), the gene and protein expression of HIF-1α, GLUT-1,GLUT-3of the local contusion cortical were detected by reversetranscription polymerase chain reaction (RT-PCR) and western-blotting ateach time point3h,6h,12h,24h,48h,72h after these TBI rats weresacrificed.Results:1.The blood glucose concentration of TBI group was increasedafter injury, significantly at6h, peaked at24h, began to decline at48h, wasstill higher than normal control group at72h.The blood glucoseconcentration of normal control group did not changed significantly.2.The glucose levels of intercellular dialysate were falling rapidly aftertraumatic brain injury, had obvious fluctuation in each period, showedlower than the control group significantly (P<0.05) at15-30min after theinjury, and then gradually recovered, at75-90min close to the glucoselevels of control group. The glucose concentration of intercellular dialysatedid not changed significantly in control group.3.The lactic acid levels of intercellular dialysate were rising rapidly aftertraumatic brain injury, had obvious fluctuation in each period, showedhigher than the control group significantly (P<0.05) at15-30min after the injury, and then gradually declined, close to the levels of control group at75-90min time point. The lactic acid concentration of intercellulardialysate did not changed significantly in normal control group.4. The levels of glucose and lactic acid of intercellular dialysate afterTBI changed significant difference (P<0.05), and the [Glu]d down and[Lac]d up the opposite trend change.5. In TBI group, HIF-1α had began to be observed positive expression incells at3h, had gradually strength enhanced, peaked at48h after TBI, andthen gradually reduced, the HIF-1α expression changes had significantdifference versus control group(P<0.05), the expression of GLUT-1incontusion area began to reduce at12h after injury, had continued until to72hours, there were significant differences versus control group (P<0.05), theexpression of GLUT-3began to increase at12h after injury, reach to thetop at72h after injury, then began to decline, but were still higher thancontrol group. There were significant differences versus control group(P<0.05). In control group, the expression changes of GLUT-1andGLUT-3was not obvious, and had not observed positive expression ofHIF-1α.Conclusions: The levels changes of blood glucose, glucose and lacticacid in intercellular dialysate, expression changes of GLUT-1, GLUT-3andHIF-1α had sequential features: the glucose metabolism changes of contusion area of brain happened firstly, followed by expression of HIF-1α,and then expression changes of GLUT-1and GLUT-3. The changes ofblood glucose and brain glucose metabolism after TBI may be resultsof body compensatory and the obstacles of glucose transport and the usagein brain. The mechanism of glucose changes was complex.6~12hours may be a key period of glucose metabolism related genes and proteinchanges in contusion area after TBI, this period may be the optimum periodto control blood glucose. PART TWOPREPARATION OF HIGH SENSITIVE GLUCOSE BIOSENSORAND APPLIED FOR DETECTING OF CEREBROSPINAL FLUIDGLUCOSE LEVELS IN PATIENTS WITH TRAUMATIC BRAININJURYObjective: To manufacture high sensitive glucose biosensor based onnanomaterials and to explore the feasibility of using the high sensitiveglucose biosensor to dynamic monitor cerebrospinal glucose levels inpatients with traumatic brain injury.Methods: The cerebrospinal fluid glucose levels of clinical samples obtained from5TBI patients were detected with high sensitive glucosebiosensor and compared the detecting range, accuracy, sensitivity, precisionwith the glucose oxidase end point method.Results:1.The response current increases linearly with the glucoseconcentration in the range of1.2×106to1.6×103M with a correlationcoefficient of0.998(n=20), and the detection limit of4.0×10-7M isestimated at signal-to-noise ration of three. High sensitive glucosebiosensor has its detecting range and high sensitive.2.The relative standarddeviation (R.S.D.) of intra-assay and inter-assay were found to be3.8%and5.1%. Glucose biosensor method has good accuracy and reproducibility.3.The effect of interference by measurement of0.2mM glucose in PBScontaining a specified concentration of the interfering compounds (ascorbicacid, uric acid, acetaminophen and L-cys) on the current response ofenzyme catalysis could be negligible under the testing conditions.Glucosebiosensor has good anti-interference.4.The accuracy of glucosedetermination was examined by comparing the results with those from theclinical analysis method (GLU-GOD-PAP method).The samples werediluted by ten times and the relative deviation of these results is between-6.45%and8.69%, This finding revealed a good agreement between theboth analytical methods.Glucose biosensor has high detection precision.Conclusions: Using high sensitive glucose biosensor to detect CSF glucose levels in patients with traumatic brain injury has characteristics ofhigh glucose detection response sensitivity, precision and accuracy, and ithas strong anti-interference ability. Compared with the traditional methodof glucose oxidase method, this method is more sensitive, quickly. Appliedhigh sensitive glucose biosensor for dynamic monitoring of cerebrospinalfluid glucose levels in patients with traumatic brain injury is feasible. PART THREECLINICAL SIGNIFICANCE OF DYNAMIC MONITORING ICPAND CCP WITH BLOOD BRAIN BARRIER INDEX IN PATIENTSAFTER TRAUMATIC BRAIN INJURYObjective: To explore the correlation of the blood brain barrier indexwith the severity and progress in patients after traumatic brain injury bydetecting and dynamic monitoring them.Methods: Detected and dynamic monitored the blood brainbarrier index, GCS scores, intracranial pressure(ICP) and cerebralperfusion pressure(CCP) of30patients, analyzed the correlation of them. Results: The blood brain barrier indexes of all the patients were higherthan the normal range reported in the literature, and waspositively correlated with the severity of TBI and consistent with theprogress of the injury.Conclusions: The permeability of BBB changed after TBI and itsfunction was impacted.Dynamic monitoring the blood brain barrier indexwith ICP and CCP might objectively reflect the progress of traumaticcondition.The BBB index could be used as a clinical marker indicator inthe clinical observation after traumatic brain injury. PART FOURCLINICAL SIGNIFICANCE OF DYNAMIC MONITORING ICPAND CCP COMBINED CSF BIOMARKER S100β AND NSE INPATIENTS AFTER TRAUMATIC BRAIN INJURYObjectives: To explore the correlation between S100β(S100β protein)and NSE(neuron-specific enolase,NSE) levels in cerebrospinal fluid (CSF)and the traumatic brain injury severity and progression by dynamicmonitored S100β and NSE levels in CSF after traumatic brain injury(TBI) and analyzed the relationship of high intracranial pressure (ICP) and lowcerebral perfusion pressure(CPP).Methods: The patients after traumatic brain injury conformed toinclusion criteria at Second Affiliated Hospital of Chongqing MedicalUniversity and Chongqing Jiangjin District Central Hospital from2013January to2013October were enrolled prospectively, and undertakento investigate.All patients CSF were collected and detected fromintraventricular catheter on admission and twice daily for7days, thenrecorded the average value. Hourly measurements of ICP and CPP werealso recorded and taken the mean starting on admission and continuing for7days. Calculated the means and ICP>20mmHg, CPP<60mmHgaccumulated time in24hours,as duration and episode of high ICP,lowperfusion time (pressure times Time dose,PTD) in PTD20, PTD60.Comparison CSF S100β and NSE level to PTD20and PTD60. Thecorrelations were analyzed between dynamic changes of ICP and CCP, andthe levels of CSF S100β and NSE.Results:36patients after TBI conformed to inclusion critria weredivided into two group, the medate group (GCS9~12) in20cases,severe group (GCS4~8) in16cases. The levels of CSF S100β and NSE inall patients were increased, and positively correlated to the severity oftraumatic brain injury (GCS score). The levels of S100β were found to beclosely correlated to PTD (PTD20:r=0.35, P<0.001,PTD60:r= 0.24, P<0.001),and the level of NSE were found to be weakly correlated toPTD20(r=0.17, P=0.01), and closely related to PTD60(r=0.20, P<0.01).Thechanges of S100β and NSE levels in CSF with the progression of thepatients after TBI were consistent.Conclusions: The increased levels of S100β and NSE in CSF after TBIreflected the severity of brain injury, dynamic changes of S100β and NSElevels were consistent with the progression of the patients after TBI.Dynamic monitoring of CSF S100β and NSE levels combined ICP andCCP might objectively reflect the progress of the brain injury, predict thesecondary brain injury before obvious clinical symptoms.Dynamicmonitoring S100β and NSE levels combined ICP and CCP in patients withmoderate and severe TBI has great clinical significance.