OBJECTIVES: To explore the effects of cannabidiol on endoplasmic reticulum stress and neuronal apoptosis in rats with multiple concussions (MCC). METHODS: SD rats were randomized into sham group, MCC group, 1% tween20 (TW) treatment group, and low-dose (10 mg/kg) and high-dose (40 mg/kg) cannabidiol treatment groups. In all but the sham group, MCC models were established using a metal pendulum percussion device, after which the rats received daily intraperitoneal injections of the corresponding agents for 2 weeks. The expressions of PERK, eIF2α, ATF4, CHOP, TRIB3, p-Akt and pro-caspase-3 in the brain tissue of the rats were detected with qRT-PCR, Western blotting and immunofluorescence staining. The core targets of cannabidiol in treatment of traumatic brain injury (TBI) were identified by network pharmacology analysis, and molecular docking was carried out to simulate the interaction of cannabidiol with the factors related to endoplasmic reticulum stress and apoptosis. RESULTS: Compared with the sham-operated rats, the rat models of MCC showed significantly increased mRNA expressions of PERK, eIF2α and CHOP and protein expressions of PERK, eIF2α, ATF4, CHOP, TRIB3, p-AKT and pro-caspase-3 in the cerebral cortex. CBD treatment, especially at the high dose, obviously increased the expression of p-Akt and lowered the expression levels of the other factors tested in the rat models. Network pharmacology analysis indicated interactions of the core targets of CBD with the factors related to endoplasmic reticulum stress and TBI, and molecular docking study showed a high binding energy of CBD with multiple factors pertaining to endoplasmic reticulum stress and apoptosis. CONCLUSIONS MCC induce endoplasmic reticulum stress and apoptosis in rat brain tissues, for which CBD, especially at a high dose, provides neuroprotective effects by inhibiting endoplasmic reticulum stress and cell apoptosis.
Animals ; Endoplasmic Reticulum Stress/drug effects* ; Apoptosis/drug effects* ; Rats, Sprague-Dawley ; Activating Transcription Factor 4/metabolism* ; Transcription Factor CHOP/metabolism* ; Rats ; Eukaryotic Initiation Factor-2/metabolism* ; Signal Transduction/drug effects* ; eIF-2 Kinase/metabolism* ; Cannabidiol/pharmacology* ; Neurons/metabolism* ; Brain Concussion/metabolism* ; Male ; Molecular Docking Simulation

The current understanding of the pathophysiology of mild traumatic brain injury (mTBI) is, without doubt, incomplete. Nevertheless, we tried to summarize the state-of-the-art explanation of how the brain is continuously injured even after a single impact. We also reviewed the real struggle of diagnosing mTBI, which culminated in showing the potential of blood-based biomarkers as an alternative or complementary way to overcome this difficulty. Pathophysiology of mTBI is subdivided into primary and secondary injuries. Primary injury is caused by a direct impact on the head and brain. Secondary injury refers to the changes in energy metabolism and protein synthesis/degradation resulting from the biochemical cascades as follows; calcium influx, mitochondrial dysfunction, fractured microtubules, and Wallerian degeneration, neuroinflammation, and toxic proteinopathy. Since the diagnosis of mTBI is made through the initial clinical information, it is difficult and inaccurate to diagnose mTBI without the absence of a witness or sign of head trauma. Blood-based biomarkers are expected to play an important role in diagnosing mTBI and predicting functional outcomes, due to their feasibility and the recent progress of targeted proteomics techniques (i.e., liquid chromatography tandem mass spectrometry [LC-MS/MS]).
Biomarkers* ; Brain ; Brain Concussion ; Brain Injuries* ; Calcium ; Chromatography, Liquid ; Craniocerebral Trauma ; Diagnosis ; Energy Metabolism ; Head ; Microtubules ; Proteomics ; Tandem Mass Spectrometry ; Wallerian Degeneration

OBJECTIVE: To observe the changes of malondialdehyde (MDA), superoxide dismutase (SOD), tumor necrosis factor-alpha (TNF-alpha), and interleukin-1beta (IL-1beta) in rat brain tissue and to explore the mechanism of secondary cerebral injury after brain concussion. METHODS: The brain concussion model was established with the pathological changes of rat brain tissue by Weil stain. The expressions of MDA and SOD in brain tissue were examined by photochemical method. The expressions of TNF-alpha and IL-1beta in cerebral cortex and hippocampus were examined by immunochemistry. RESULTS: Nerve myelin sheath showed disorder, disruption, gryposis and swelling by Weil stain. Above changes were more severe at 12h. The quantity of MDA in rat brain tissue after concussion was significantly higher than that in the control group. The activity of SOD was significantly lower than that in the control group. The expressions of TNF-alpha and IL-1beta increased more significantly in cerebral cortex and hippocampus in rat brain tissue after concussion than that in the control group. CONCLUSION Oxidative stress and inflammatory injury in the rat brain tissue, which may play an important role in secondary cerebral injury after concussion.
Animals ; Brain/metabolism* ; Brain Concussion/metabolism* ; Brain Injuries ; Hippocampus ; Interleukin-1beta/metabolism* ; Malondialdehyde/metabolism* ; Oxidative Stress ; Rats ; Superoxide Dismutase/metabolism* ; Tumor Necrosis Factor-alpha/metabolism*

OBJECTIVE: By observing the cerebral beta-amyloid precursor protein (beta-APP) expression in the chronic alcoholism rats with slight cerebral injury, to discuss the correlation of chronic alcoholism and death caused by traumatic subarachnoid haemorrhage (TSAH). METHODS: Sixty male SD rats were randomly divided into watering group, watering group with strike, alcoholism group and alcoholism group with strike. Among them, the alcohol was used for continuous 4 weeks in alcoholism groups and the concussion was made in groups with strike. In each group, HE staining and immunohistochemical staining of the cerebral tissues were done and the results were analyzed by the histopathologic image system. RESULTS: In watering group, there was no abnormal. In watering group with strike, mild neuronic congestion was found. In alcoholism group, vascular texture on cerebral surface was found. And the neurons arranged in disorder with dilated intercellular space. In alcoholism group with strike, diffuse congestion on cerebral surface was found. And there was TSAH with thick-layer patches around brainstem following irregular axonotmesis. The quantity of beta-APP IOD in alcoholism group was significantly higher in the frontal lobe, hippocampus, cerebellum, brainstem than those in watering group with strike and alcoholism group with strike. CONCLUSION The cerebral tissues with chronic alcoholism, due to the decreasing tolerance, could cause fatal TSAH and pathological changes in cerebral tissues of rats under slight cerebral injury.
Alcoholism/pathology* ; Amyloid beta-Protein Precursor/metabolism* ; Animals ; Brain/pathology* ; Brain Concussion/pathology* ; Disease Models, Animal ; Ethanol/adverse effects* ; Male ; Neurons/pathology* ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Subarachnoid Hemorrhage, Traumatic/pathology*

OBJECTIVE: To observe e-jun protein expression after rat brain concussion and explore the forensic pathologic markers following brain concussion. METHODS: Fifty-five rats were randomly divided into brain concussion group and control group. The expression of c-jun protein was observed by immunohistochemistry. RESULTS: There were weak positive expression of c-jun protein in control group. In brain concussion group, however, some neutrons showed positive expression of c-jun protein at 15 min after brain concussion, and reach to the peak at 3 h after brain concussion. CONCLUSION The research results suggest that detection of c-jun protein could be a marker to determine brain concussion and estimate injury time after brain concussion.
Animals ; Brain/pathology* ; Brain Concussion/pathology* ; Brain Stem/metabolism* ; Cerebral Cortex/metabolism* ; Disease Models, Animal ; Female ; Forensic Pathology ; Immunohistochemistry ; Male ; Neurons/metabolism* ; Proto-Oncogene Proteins c-jun/metabolism* ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Time Factors

OBJECTIVE: To study the changes of expression of relevant factors in rat brain after concussion injury and to provide scientific basis for forensic estimation of brain injury interval. METHODS: Brain tissues were sampled from the established SD rat animal model of brain concussion, routinely processed and stained with HE and immunohistochemically stained with antibodies directed against heat shock protein 70 (HSP70), transforming growth factor beta 1 (TGF-beta1) and basic fibroblast growth factor (bFGF). The sections were examined under light microscope with IMAGE analytical system and homologous statistical analysis. RESULTS: The expression of HSP 70 was observed in 30 minutes after brain injury. The amount of neurons expressing HSP 70 increased gradually, reached its peak at 12 hours and then declined at 24 hours after brain injury. The expression of bFGF was observed 3 hours after injury in brain stem, reached its peak at 12 hours, and then declined. The expression of TGF-beta1 was detected 6-24 hours after brain injury, remained at its peak up to 3 days. CONCLUSION Brain injury can induce a chronological expression of HSP70, bFGF and TGF-beta1. The results can be a potential for estimating the age of brain injury using several markers.
Animals ; Brain/pathology* ; Brain Concussion/pathology* ; Cerebral Cortex/pathology* ; Disease Models, Animal ; Fibroblast Growth Factor 2/metabolism* ; HSP70 Heat-Shock Proteins/metabolism* ; Hippocampus/pathology* ; Immunohistochemistry ; Male ; Neurons/metabolism* ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Staining and Labeling ; Time Factors ; Transforming Growth Factor beta1/metabolism*

OBJECTIVE: To evaluate the expression of Bcl-2 protein after brain concussion. METHODS: Expression levels of Bel-2 protein in cortex, pontine and cerebellum of rats were investigated using immunohistochemistry. RESULTS: There was no expression of Bcl-2 protein in control group seen. The expression of Bcl-2 protein in brain concussion groups was detected at l hour, and the expression level reached its peak 4 days after the concussion and then declined gradually. CONCLUSION Our findings suggest that the detection of Bel-2 protein could be an indicator for diagnosis of brain concussion and for estimation of the post injury time interval.
Animals ; Brain/pathology* ; Brain Concussion/metabolism* ; Brain Stem/pathology* ; Cerebral Cortex/pathology* ; Contusions/pathology* ; Disease Models, Animal ; Female ; Immunohistochemistry ; Male ; Neurons/pathology* ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; Rats ; Rats, Sprague-Dawley ; Time Factors

OBJECTIVE: To study the expression of GFAP and pathologic changes after rats brain concussion, so that to provide evidence on brain concussion for forensic identification. METHODS: Forty-five SD rats were divided into 3, 6, 12, 24 h and 2, 4, 7, 10 d and normal control groups in terms of different wounding time after brain concussion model established, and the expression of GFAP after rats brain concussion were then observed by using SP immunohistochemical method. RESULTS: In normal control brain, low-level GFAP expressions could be observed. After six hours' brain concussion, GFAP positive cells increased obviously. The trend reached to the peak at 7d, partly declined at 10d, then decreased gradually. CONCLUSION Brain concussion induced the expression of GFAP. The detection of GFAP could be useful for diagnosis of brain concussion on forensic pathology, and could be a reference index for timing of injury after brain concussion.
Animals ; Astrocytes/pathology* ; Brain Concussion/pathology* ; Disease Models, Animal ; Female ; Forensic Pathology ; Glial Fibrillary Acidic Protein/metabolism* ; Immunohistochemistry ; Male ; Rats ; Rats, Sprague-Dawley ; Time Factors

OBJECTIVE: To study the changes of expression of c-myc protein on rats' brains after brain concussion. METHODS: sixty rats were randomly divided into brain concussion groups and control group. The expression of c-myc protein was microscopically observed by immunohistochemical method. RESULTS: No expression of c-myc protein in control group were observed. However, positive expression of c-myc protein in some neurons was seen at 20 min after brain concussion, and reach to the peak at 8h after brain concussion and then decreased gradually. CONCLUSION These findings suggest that the detection of c-myc protein could be an index of diagnosis of brain concussion.
Animals ; Brain/pathology* ; Brain Concussion/pathology* ; Brain Stem/pathology* ; Cerebral Cortex/pathology* ; Disease Models, Animal ; Female ; Immunohistochemistry ; Male ; Neurons/pathology* ; Proto-Oncogene Proteins c-myc/metabolism* ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Time Factors

OBJECTIVE: To study the relationship between expression of C-FOS protein and brain concussion and find a sensitive marker of diagnosis of the brain concussion. METHODS: Fifty-five rats were randomly divided into brain concussion groups and control group. The expression of C-FOS protein was microscopically observed by immunohistochemical method. RESULTS: There were negative expression of C-FOS protein in control group. In brain concussion group, however, positive expression of C-FOS protein in some neurons was seen at 15 min after brain concussion, and reach to the peak at 6 h after brain concussion, then decreased gradually. CONCLUSION These findings suggest that detection of C-FOS protein could be an index of diagnosis of brain concussion and a sensitive marker of timing of injury after brain concussion.
Animals ; Biomarkers ; Brain Concussion/metabolism* ; Female ; Forensic Medicine ; Immunohistochemistry ; Male ; Proto-Oncogene Proteins c-fos/genetics* ; RNA, Messenger/genetics* ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Time Factors