Curcumin Alleviates Oxidative Stress, Neuroinflammation, and Promotes Behavioral Recovery After Traumatic Brain Injury.

BACKGROUND: Neuroinflammation and oxidative stress after traumatic brain injury (TBI) can further lead to neuronal apoptosis, which plays a crucial role in the process of neuron death. Curcumin, which is derived from the rhizome of the Curcuma longa plant, has multiple pharmacological effects. OBJECTIVE: The objective of this study was to investigate whether curcumin treatment has neuroprotective effects after TBI, and to elucidate the underlying mechanism. METHODS: A total of 124 mice were randomly divided into 4 groups: Sham group, TBI group, TBI+Vehicle group, and TBI+Curcumin group. The TBI mice model used in this study was constructed with TBI device induced by compressed gas, and 50 mg/kg curcumin was injected intraperitoneally 15 minutes after TBI. Then, the blood-brain barrier permeability, cerebral edema, oxidative stress, inflammation, apoptosis-related protein, and behavioral tests of neurological function were utilized to evaluate the protective effect of curcumin after TBI. RESULTS: Curcumin treatment markedly alleviated post-trauma cerebral edema and blood-brain barrier integrity, and suppressed neuronal apoptosis, reduced mitochondrial injury and the expression of apoptosis-related proteins. Moreover, curcumin also attenuates TBI-induced inflammatory response and oxidative stress in brain tissue and improves cognitive dysfunction after TBI. CONCLUSION: These data provide substantial evidence that curcumin has neuroprotective effects in animal TBI models, possibly through the inhibition of inflammatory response and oxidative stress.

Establishment and Evaluation of a Novel High-Efficiency Model of Graded Traumatic Brain Injury in Mice.

BACKGROUND: Although previous studies have made significant contributions to establishing animal traumatic brain injury (TBI) models for simulation of human TBI, the accuracy, controllability, and modeling efficiency of animal TBI models need to be further improved. This study established a novel high-efficiency graded mouse TBI model induced by shock wave. METHODS: A total of 125 mice were randomly divided into sham, 0.7 mm, 0.6 mm, and 0.5 mm groups according to the depth of the cross groove of the aluminum sheets. The stability and repeatability of apparatus were evaluated, and the integrity of the blood-brain barrier, cerebral edema, neuropathologic immunohistochemistry, apoptosis-related protein, and behavioral tests of neurologic function were used to validate this new model. RESULTS: The results showed that 4 mice were injured simultaneously in 1 experiment. They received the same intensity of shock waves. Moreover, the mortality rates caused by 3 different aluminum sheets were consistent with the mortality rates of mild TBI, moderate TBI, and severe TBI. Compared with the sham group, mice in different injured groups significantly increased brain water content, blood-brain barrier permeability, and neuronal apoptosis. And the mice in all injured groups showed poor motor ability, balancing, spatial learning, and memory abilities. CONCLUSIONS: The novel TBI apparatus has advantages in its small size, simple operation, high repeatability, high efficiency, and graded severity. Our TBI apparatus provides a novel tool to investigate the neuropathologic changes and underlying mechanisms of TBI with various levels of severities.

Improvement in cognitive dysfunction following blast induced traumatic brain injury by thymosin α1 in rats: Involvement of inhibition of tau phosphorylation at the Thr205 epitope.

Cognitive impairment is a significant sequela of traumatic brain injury (TBI) especially blast induced traumatic brain injury (bTBI), which is characterized by rapid impairments of learning and memory ability. Although several neuroprotective agents have been postulated as promising drugs for bTBI in animal studies, very few ideal therapeutic options exist to improve cognitive impairment following bTBI. Thymosin α1(Tα1), a 28-amino-acid protein that possesses immunomodulatory functions, has exhibited beneficial effects in the treatment of infectious diseases, immunodeficiency diseases and cancers. However, it remains unclear whether Tα1 has a therapeutic role in bTBI. Thus, we hypothesized that Tα1 administration could reverse the outcomes of bTBI. The blast induced TBI (bTBI) rat model was established with the compressed gas driven blast injury model system. A consecutive Tα1 therapy (in 1 ml saline, twice a day) at a dose of 200 µg/kg or normal saline (NS) (1 ml, twice a day) for 3 days or 2 weeks was performed. Utilizing our newly designed bTBI model, we investigated the beneficial effects of Tα1 therapy on rats exposed to bTBI including: cognitive functions, general histology, regulatory T (Treg) cells, edema, inflammation reactions and the expression and phosphorylation level of tau via Morris Water Maze test (MWM test), HE staining, flow cytometry, brain water content (BWC) calculation, IL-6 assay and Western blotting, respectively. Tα1 treatment seemed to reduce the 24-hour mortality, albeit with no statistical significance. Moreover, Tα1 treatment markedly improved cognitive dysfunction by decreasing the escape latency in the acquisition phase, and increasing the crossing numbers in the probe phase of MWM test. More interestingly, Tα1 significantly inhibited tau phosphorylation at the Thr205 epitope, but not at the Ser404 and Ser262 epitopes. Tα1 increased the percentage of Treg cells and inhibited plasma IL-6 production on 3d post bTBI. Moreover, Tα1 suppressed brain edema as demonstrated by decrease of BWC. However, there was a lack of obvious change in histopathology in the brain upon Tα1 treatment. This is the first study showing that Tα1 improves neurological deficits after bTBI in rats, which is potentially related to the inhibition of tau phosphorylation at the Thr205 epitope, increased Treg cells and decreased inflammatory reactions and brain edema.

A novel model of blast induced traumatic brain injury caused by compressed gas produced sustained cognitive deficits in rats: involvement of phosphorylation of tau at the Thr205 epitope.

Improvised explosive devices (IEDs) represent the leading causes for casualties among civilians and soldiers in the present war (including counter-terrorism). Traumatic brain injury (TBI) caused by IEDs results in different degrees of impairment of cognition and behavior, but the exact brain pathophysiological mechanism following exposure to blast has not been clearly investigated. Here, we sought to establish a rat model of closed-head blast injury using compressed gas to deliver a single blast only to the brain without systemic injuries. The cognitive functions of these bTBI models were assessed by Morris Water Maze test (MWM test). The HE staining, flow cytometry, ELISA and Western Blotting were used to measure the effects of shock wave on general histology, regulatory T (Treg) cells percentage, inflammatory reactions, the expression and phosphorylation level of tau, respectively. In addition, the brain water content and 24 -h mortality were also assessed. As the distance from the blast source increased, the input pressure did not change, the overpressure decreased, and the mortality decreased. Receiver operating characteristic (ROC) curves for predicting 24 -h mortality using peak overpressure fits with the following areas under ROC curves: 0.833. In 2 weeks after blast injury, cognitive tests revealed significantly decreased performance at 20 cm distance from the blast (about 136.44 kPa) as demonstrated by increased escape latency in the acquisition phase, and decreased crossing numbers in the probe phase of MWM test. Interestingly, a single blast exposure (at 20 cm) lead to significantly increased tau phosphorylation at the Thr205 epitope but not at the Ser404 and Ser262 epitopes at 12 h, 24 h, 3d, and 7d after blast injury. Blast decreased the percentage of CD4+T cells, CD8+T cells, Treg cells and lymphocytes at different time points after blast injury, and blast increased the percentage of neutrophils at 12 h after blast injury and significantly increased IL-6 production at 12 h, 24 h and 3d after blast injury. In addition, blast lead to an increase of brain edema at 24 h and 3d after blast injury. However, no obvious alterations in brain gross pathology were found acutely in the blast-exposed rats. In conclusion, we established a rat model of simple craniocerebral blast injury characterized by impairment of cognitive function, Thr205 phosphorylation of tau, decreased Treg cells and increased inflammatory reactions and brain edema. We expect this model may help clarify the underlying mechanism after blast injury and possibly serve as a useful animal model in the development of novel therapeutic and diagnostic approaches.

Sex Differences Associated With Circulating PCSK9 in Patients Presenting With Acute Myocardial Infarction.

A limited number of studies have explored whether the role of circulating proprotein convertase subtilisin/kexin type 9 (PCSK9) in the pathogenesis of acute myocardial infarction (AMI) is sex specific. The purpose of the present study was to examine sex differences in plasma PCSK9 in Chinese patients with AMI. In this study, a total of 281 records from patients presenting with AMI were analyzed.We compared hospital data and plasma PCSK9 levels by sex difference for inpatients presenting with AMI. After 1 year of follow-up, major adverse cardiac events(MACE) were recorded. A Cox proportional hazards model was used to calculate hazard ratios with 95% confidence intervals. We found that, compared with male groups, PCSK9 levels were higher in female patients not only for overall patients with AMI but also for patients with ST-elevation myocardial infarction (STEMI) (median: 273.6 [215.6-366.8] vs. 325.1 [247.5-445.3] ng/ml, P = 0.0136; 273.4 [215.6-369.7] vs. 317.1 [249.6-450.1], P = 0.0275, respectively). The cumulative incidence of cardiac death and 1-year MACE were significantly higher in the female group compared with male group (10% vs. 2.74%, P = 0.025; 15% vs. 4.11%, P = 0.0054, respectively). On multivariate Cox regression analysis, female sex, total triglyceride, glycosylated hemoglobin A, and homocysteic acid were independent risk factors of 1-year MACE. There was no significant correlation between PCSK9 and 1-year MACE in total AMI patients. In conclusion, PCSK9 levels and 1-year MACE were higher in women with AMI than in men with AMI, however, female sex but not PCSK9 were significant correlated with the 1-year MACE. The clinical implications of this finding are worthy of further investigations and must be confirmed in larger cohorts.

Effects of Short-term High Dose Atorvastatin on Left Ventricular Remodeling in Patients with First Time Attack of Anterior Acute Myocardial Infarction.

Objects The aim of this trial was to evaluate the effect of short-term high-dose atorvastatin therapy on levels of high-sensitivity C-reactive protein (hs-CRP), malonaldehyde (MDA), endothelin-1(ET-1), matrix metalloproteinases (MMPs), and left ventricular (LV) remodeling in patients with first time attack of acute anterior myocardial infarction (AAMI) .Methods A hundred and three patients with first time attack of AAMI who underwent successful primary percutaneous coronary intervention were randomized to receive atorvastatin 40 mg once daily for 1 week followed by 20 mg once daily (intensive treatment group, IT group, n=49), or atorvastatin 20 mg once daily (standard treatment group, ST group, n=54). Plasma levels of hs-CRP, MDA, ET-1, MMP-2 and MMP-9 were measured on admission, at 1 week, 2 weeks and 6 months follow up and compared between the IT group and ST group. Echocardiography was performed on admission, at 2 week, and 1 year follow up. The left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV) and left ventricular ejection fraction (LVEF) were measured at each echocardiographic examination and compared between the IT group and ST group.Results Plasma levels of hs-CRP (F=7.718, P=0.009), ET-1 (F=7.882, P=0.006), MMP-9 (F=4.834, P=0.028) and pro-BNP (F=4.603, P=0.032) were significantly lower at 1 week after initial onset of AAMI in the IT group compared with the ST group. The changes of LVEDV, LVESV, and LVEF at the 1 year follow-up from the admission did not differ between the IT group and the ST group (t=0.722, P=0.444; t=1.228, P=0.221; t=1.354, P=0.187, repectively).Conclusions Short-term high-dose atorvastatin treatment for AAMI was associated with lower hs-CRP, ET-1 and MMP-9 levels compared to the standard dose treatment. However, this beneficial effect is not likely to related to the left ventricular remodeling.

[Construction of Lentiviral Vector Over-Expressing MEG3 and Its Effect on XG-7 Cell Apoptosis].

OBJECTIVE: To construct a recombinant lentiviral expression vectors carrying MEG3 and to evaluate its effects on XG-7 cell apoptosis. METHODS: A full-length genomic fragment of human MEG3 was cloned from the pcDNA3.0-MEG3 packaging plasmid and was amplified by PCR. New restriction sites were introduced to be blunted with T4 DNA Ligase. The sequence of the amplified segments was sub-cloned into lentivirus expression vector pCDH-EF1-MCS-T2A-copGFP.The recombined lentiviral expression vector was transfected into 293T cells. FACS was used to detect the effect of MEG3 on XG-7 cell apoptosis after being infected by optimized MOI. RESULTS: The recombined lentiviral expression vector pCDH-EF1-MEG3-copGFP was constructed successfully. The results showed that pCDH-EF1-MEG3-copGFP could increase the mRNA expression of MEG3 dramatically, its transfection efficiency was more than 90%. The apoptosis rate in XG-7 cells (26.8±2.8%) was very significantly higher than that of the control group (P<0.01). CONCLUSION: The recombined lentiviral LncRNA expression vector targeting MEG3, pCDH-EF1-MEG3-copGFP, has been successfully constructed, the pCDH-EF1-MEG3-copGFP can induce the cell apoptosis in human myeloma cell lines. This study set up a basis to further explore the relationship between human myeloma cells and LncRNA-MEG3 gene.

Cilostazol inhibits plasmacytoid dendritic cell activation and antigen presentation.

BACKGROUND: Cilostazol, an anti-platelet drug for treating coronary heart disease, has been reported to modulate immune cell functions. Plasmacytoid dendritic cells (pDCs) have been found to participate in the progression of atherosclerosis mainly through interferon α (IFN-α) production. Whether cilostazol influences pDCs activation is still not clear. In this study, we aimed to investigate the effects of cilostazol on cell activation and antigen presentation of pDCs in vitro in this study. METHODS: Peripheral blood mononuclear cells isolated by Ficoll centrifugation and pDCs sorted by flow cytometry were used in this study. After pretreated with cilostazol for 2 h, cells were stimulated with CpG-A, R848 or virus for 6 h or 20 h, or stimulated with CpG-B for 48 h and then co-cultured with naïve T cell for five days. Cytokines in supernatant and intracellular cytokines were analyzed by ELISA or flow cytometry respectively. RESULTS: Our data indicated that cilostazol could inhibit IFN-α and tumor necrosis factor α (TNF-α) production from pDCs in a dose-dependent manner. In addition, the ability of priming naïve T cells of pDCs was also impaired by cilostazol. The inhibitory effect was not due to cell killing since the viability of pDCs did not change upon cilostazol treatment. CONCLUSION: Cilostazol inhibits pDCs cell activation and antigen presentation in vitro, which may explain how cilostazol protects against atherosclerosis.

κ-opioid receptor activation prevents against arrhythmias by preserving Cx43 protein via alleviation of intracellular calcium.

κ-opioid receptor (κ-OR) activation with U50,488H, a selective κ-OR agonist, has been previously demonstrated to prevent against cardiac arrhythmias via stabilizing the synthesis and degradation of an integral membrane protein, Cx43, in gap junctions. However, the exact prevention mechanism remains unclear. The present study tested the hypothesis that the kappa OR agonist U50,488H mediates the prevention of arrhythmia through the regulation of intracellular calcium leading to the preservation of Cx43 protein. By performing electrocardiogram monitoring and immunoblotting in isolated Langendorff-perfused rat hearts, high concentrations of calcium-perfused rat hearts exhibited increased cardiac arrhythmias. Diminished expression of Cx43 protein was observed. The utilization of a whole-cell patch clamp technique revealed that U50,488H inhibited L-type calcium current in single ventricular myocytes in a dose-dependent manner. These effects were blocked by nor-binaltorphimine, potent and selective κ-OR antagonists. Administration of U50,488H before myocardial ischemia resulted in an attenuated of total arrhythmia scores. The attenuation effect was blocked by nor-binaltorphimine. The attenuation effect was antagonized both by Bay K8644, a L-type calcium channel agonist, and also by the Cx43 uncoupler heptanol. Finally, immunoblotting data demonstrated that the preservation of Cx43 protein conferred by U50,488H was reversed in the presence of Bay K8644. In summary, the present study demonstrates κ-OR activation with U50,488H may confer antiarrhythmic effects via modulation of the calcium-Cx43 pathway.

Vasculoprotective effect of U50,488H in rats exposed to chronic hypoxia: role of Akt-stimulated NO production.

Impairment of pulmonary endothelium function in the pulmonary artery is a direct result of chronic hypoxia. This study is to investigate the vasculoprotective effects of U50,488H (a selective κ-opioid receptor agonist) and its underlying mechanism in hypoxia-induced pulmonary artery endothelial functional injury. Chronic hypoxia was simulated by exposing the rats to 10% oxygen for 2 wk. After hypoxia, right ventricular pressure (RVP) and right ventricular hypertrophy index (RVHI) were measured. The pulmonary vascular dysfunction, effect of nitric oxide synthase inhibitor (l-NAME) on the relaxation of U50,488H, and level of nitric oxide (NO) were determined. In vitro, the signaling pathway involved in the anti-apoptotic effect of U50,488H was investigated. Cultured endothelial cells were subjected to simulated hypoxia, and cell apoptosis was determined by TUNEL staining. U50,488H (1.25 mg/kg) significantly reduced RVP and RVHI in hypoxia. U50,488H markedly improved both pulmonary endothelial function (maximal vasorelaxation in response to ACh: 74.9 ± 1.8%, n = 6, P <0.01 vs. hypoxia for 2 wk group) and increased total NO production (1.65 fold). U50,488H relaxed the pulmonary artery rings of the hypoxic rats. This effect was partly abolished by l-NAME. In cells, U50,488H both increased NO production and reduced hypoxia-induced apoptosis. Moreover, pretreatment with nor-binaltorphimine (nor-BNI, a selective κ-opioid receptor antagonist), PI3K inhibitor, Akt inhibitor or l-NAME almost abolished anti-apoptotic effect exerted by U50,488H. U50,488H resulted in increases in Akt and eNOS phosphorylation. These results demonstrate that pretreatment with U50,488H attenuates hypoxia-induced pulmonary vascular endothelial dysfunction in an Akt-dependent and NO-mediated fashion.

Development of a rat respiratory mask and its application in experimental chronic myocardial ischaemia.

In addressing the challenge of the low survival rates of rats with myocardial ischaemia, we developed a novel respiratory mask. We tested this mask on the rat model. We gave attention to several features of the mask: (1) shape, (2) size, (3) inlet, (4) outlet, (5) compatibility between rat head and the mask, (6) connection between mask and ventilator. We found certain features, especially to influence mask efficacy. These features include: mask shape, mask inlet and outlet, mask connection to the respiratory machine, mask mount on the rat head. We examined the rat mask in a model of chronic myocardial ischaemia; our model was the ligation of the coronary artery. The rats with the masks experienced an increase in survival by a factor of 50-90% compared with rats deprived of the masks. Towards the examination of myocardial ischaemia, our new mask may offer a platform replete with both efficiency and stability.

Antiarrhythmic effect mediated by κ-opioid receptor is associated with Cx43 stabilization.

OBJECTIVE: Acute myocardial ischemia induces electrical and chemical uncoupling of gap junctions, which contributes to conduction abnormalities and re-entrant arrhythmias. We tested the hypothesis that structure and function of Connexin43 may vibrate during acute myocardial ischemia and reperfusion and κ-opioid receptor stimulation may stabilize the alteration of Connexin43. DESIGN: An animal intervention study was conducted with comparison to a control group. SETTING: University preclinical research laboratory. SUBJECTS: Age-, weight-, and sex-matched Sprague-Dawley rats. INTERVENTIONS: Adult rat hearts were subjected to ischemia or ischemia/reperfusion, which was induced by temporary occlusion of the left main coronary artery. U50488H was given 10 mins before tissue specimens were taken or before ischemia (1.5 mg/kg, intravenous) and nor-BNI was given 15 mins before tissue specimens were taken or before ischemia (2 mg/kg, intravenous). Tissue samples came from left ventricular myocardium of the rat hearts. MEASUREMENTS AND MAIN RESULTS: Electrocardiogram, immunohistochemistry, immunoblotting, and reverse transcription-polymerase chain reaction were used to measure changes of arrhythmias, protein, and gene expression of Connexin43, respectively. κ-opioid receptor activation with U50 decreased arrhythmia in a model of myocardial ischemia and reperfusion. In normal hearts, immunohistochemical data showed reduced amount and lateralization of Connexin43 induced by κ-opioid receptor activation, whereas immunoblotting data demonstrated no significant changes between control and U50 group. During ischemia, however, Connexin43 protein underwent dephosphorylation and degradation, and Connexin43 mRNA was upregulated. These alterations were significantly attenuated on κ-opioid receptor stimulation. During ischemia and reperfusion, Connexin43 protein underwent dephosphorylation and degradation and recovered slowly during reperfusion. Activation of κ-opioid receptor accelerated recovery of phosphorylated and total Connexin43. CONCLUSIONS: In normal rat hearts, Connexin43 translocates from intercellular junctions to intracellular locations on κ-opioid receptor activation. In rat hearts experiencing acute myocardial ischemia and reperfusion, protein and gene expression of Connexin43 undergo vibration. This phenomenon is stabilized when κ-opioid receptor is activated and by the fact that κ-opioid receptor produces antiarrhythmic effects.