Xiaogang Tao

Protective actions of PJ34, a poly(ADP-ribose)polymerase inhibitor, on the blood–brain barrier after traumatic brain injury in mice

Poly(ADP-ribose) polymerase (PARP) is activated by oxidative stress and plays an important role in traumatic brain injury (TBI). The objective of this study was to investigate whether PARP activation participated in the blood-brain barrier (BBB) disruption and edema formation in a mouse model of controlled cortical impact (CCI). N-(6-oxo-5,6-dihydrophenanthridin-2-yl)-N,N-dimethylacetamide (PJ34) (10 mg/kg), a selective PARP inhibitor, was administered intraperitoneally at 5 min and 8 h after experimental CCI. After 6 h and 24 h of CCI, the permeability of the cortical BBB was determined after Evans Blue administration. The water content of the brain was also measured. Treatment with PJ34 markedly attenuated the permeability of the BBB and decreased the brain edema at 6 h and 24 h after CCI. Our data showed the up-regulation of nuclear factor-κB in cytosolic fractions and nuclear fractions in the injured cortex, and these changes were reversed by PJ34. Moreover, PJ34 significantly lessened the activities of myeloperoxidase and the levels of matrix metalloproteinase-9, enhanced the levels of occludin, laminin, collagen IV and integrin β1, reduced neurological deficits, decreased the contusion volume, and attenuated the necrotic and apoptotic neuronal cell death. These data suggest the protective effects of PJ34 on BBB integrity and cell death during acute TBI.

Hydrogen-rich water attenuates brain damage and inflammation after traumatic brain injury in rats.

Inflammation and oxidative stress are the two major causes of apoptosis after traumatic brain injury (TBI). Most previous studies of the neuroprotective effects of hydrogen-rich water on TBI primarily focused on antioxidant effects. The present study investigated whether hydrogen-rich water (HRW) could attenuate brain damage and inflammation after traumatic brain injury in rats. A TBI model was induced using a controlled cortical impact injury. HRW or distilled water was injected intraperitoneally daily following surgery. We measured survival rate, brain edema, blood-brain barrier (BBB) breakdown and neurological dysfunction in all animals. Changes in inflammatory cytokines, inflammatory cells and Cho/Cr metabolites in brain tissues were also detected. Our results demonstrated that TBI-challenged rats exhibited significant brain injuries that were characterized by decreased survival rate and increased BBB permeability, brain edema, and neurological dysfunction, while HRW treatment ameliorated the consequences of TBI. HRW treatment also decreased the levels of pro-inflammatory cytokines (TNF-α, IL-1β and HMGB1), inflammatory cell number (Iba1) and inflammatory metabolites (Cho) and increased the levels of an anti-inflammatory cytokine (IL-10) in the brain tissues of TBI-challenged rats. In conclusion, HRW could exert a neuroprotective effect against TBI and attenuate inflammation, which suggests HRW as an effective therapeutic strategy for TBI patients.

Neuroprotective efficacy of decompressive craniectomy after controlled cortical impact injury in rats: An MRI study.

Decompressive craniectomy (DC) is one of the therapeutic options for severe traumatic brain injury (TBI), and it has long been used for the treatment of patients with malignant post-traumatic brain edema. However, a lack of definitive evidence prevents physicians from drawing any conclusions about the efficacy of DC for the treatment of TBI. Magnetic resonance imaging (MRI) is widely used to evaluate the effects of TBI in both experimental and clinical studies. Therefore, the aim of the present study was to investigate the MRI assessment of DC post-TBI in rats to provide experimental animal data and radiological evidence to support the clinical application of DC. We used both in vivo MRI and proton magnetic resonance spectroscopy ((1)H-MRS) to evaluate the therapeutic effect of DC on lateral controlled cortical impact (CCI) rat models at 3h, 1 d, 2 d, 3d and 7d after TBI. Our data suggest that DC can reduce brain edema; decrease the apparent diffusion coefficient value, contusion volume and lactate (Lac)/creatine (Cr) ratio; and increase the N-acetylaspartate (NAA)/Cr and choline (Cho)/Cr ratios after TBI. The present results suggest that DC can indeed reduce brain edema formation and exhibits good neuroprotective efficacy after CCI injury in rats.

Decompressive craniectomy for severe traumatic brain injury patients with fixed dilated pupils

Objective The outcome of decompressive craniectomy (DC) for severe traumatic brain injury (sTBI) patients with fixed dilated pupils (FDPs) is not clear. The objective of this study was to validate the outcome of DC in sTBI patients with FDPs. Patients We retrospectively collected data from 207 sTBI patients with FDPs during the time period of May 4, 2003–October 22, 2013: DC group (n=166) and conservative care (CC) group (n=41). Measurements Outcomes that were used as indicators in this study were mortality and favorable outcome. The analysis was based on the Glasgow Outcome Scale recorded at 6 months after trauma. Results A total of 49.28% patients died (39.76% [DC group] vs 87.80% [CC group]). The mean increased intracranial pressure values after admission before operation were 36.20±7.55 mmHg in the DC group and 35.59±8.18 mmHg in the CC group. After performing DC, the mean ICP value was 14.38±2.60 mmHg. Approximately, 34.34% sTBI patients with FDPs in the DC group gained favorable scores and none of the patients in the CC group gained favorable scores. Conclusion We found that DC plays a therapeutic role in sTBI patients with FDPs, and it is particularly important to reduce intracranial pressure as soon as possible after trauma. For the patients undergoing DC, favorable outcome and low mortality could be achieved.

Primary Intracranial Alveolar Soft-Part Sarcoma: Report of Two Cases and a Review of the Literature

BACKGROUND Alveolar soft part sarcoma (ASPS), a rare malignant soft-tissue sarcoma affecting mainly adolescents and young children, frequently metastasizes to the brain. Primary intracranial ASPS, however, is extremely rare. We present 2 cases of primary intracranial ASPS without demonstrable systemic lesions. CASE PRESENTATION We report 2 cases of primary intracranial lesions that were surgically treated, and a postoperative diagnosis of ASPS was determined in both of the cases. The tumor in the 28-year-old female patient completely resolved after a treatment course consisting of surgical intervention and radiotherapy. After a follow-up period of 27 months, the patient was tumor-free. The other patient was a 13-year-old boy with a right middle cranial fossa tumor who experienced subtotal surgery, experienced a tumor relapse, and died 2 years after surgery. CONCLUSIONS This is the fifth report about primary intracranial ASPS. We herein present the clinical pathologic characteristics, imaging features, and differential diagnosis of primary ASPS of the brain. Gross total resection is the most effective therapeutic option for primary intracranial ASPS.

Decompressive craniectomy protects against hippocampal edema and behavioral deficits at an early stage of a moderately controlled cortical impact brain injury model in adult male rats

HighlightsDC could attenuate TBI‐induced learning and memory deficits.DC could normalize MMP‐9 expression levels and reduce hippocampus edema formation after TBI.DC could stabilize expression of Synapsin I and potentially maintain hippocampal synaptic function after TBI.The reduction of hippocampus edema formation induced by DC was evidenced by increased ADC values. ABSTRACT A decompressive craniectomy (DC) has been shown to be a life‐saving therapeutic treatment for traumatic brain injury (TBI) patients, which also might result in post‐operative behavioral dysfunction. However, there is still no definite conclusion about whether the behavioral dysfunction already existed at an early stage after the DC operation or is just a long‐term post‐operation complication. Therefore, the aim of the present study was to analyze whether DC treatment was beneficial to behavioral function at an early stage post TBI. In this study, we established a controlled cortical impact injury rat model to evaluate the therapeutic effect of DC treatment on behavioral deficits at 1 d, 2 d, 3 d and 7 d after TBI. Our results showed that rats suffered significant behavioral and mood deficits after TBI compared to the control group, while decompressive craniectomy treatment could normalize MMP‐9 expression levels and reduce hippocampal edema formation, stabilize the expression of Synapsin I, which was a potential indicator of maintaining the hippocampal synaptic function, thus counteracting behavioral but not mood decay in rats subjected to TBI. In conclusion, decompressive craniectomy, excepting for its life‐saving effect, could also play a potential beneficial neuroprotective role on behavioral but not mood deficits at an early stage of moderate traumatic brain injury in rats.

Protective functions of PJ34, a PARP inhibitor, is related to down-regulation of calpain and NF-κB in a mouse model of TBI

OBJECTIVES Poly(ADP-ribose) polymerase (PARP), calpain, and nuclear factor-κB (NF-κB) are reported to participate in inflammatory reactions in pathologic conditions and are involved in traumatic brain injury. The objective of this study was to investigate whether PARP participates in inflammation related to calpain and NF-κB in a mouse model of controlled cortical impact (CCI). METHODS PJ34 (10 mg/kg), a selective PARP inhibitor, was administered intraperitoneally 5 minutes and 8 hours after experimental CCI. We then performed a histopathologic analysis, and we measured calpain activity and protein levels in all animals. The cytosolic, mitochondria, and nuclear fractions were prepared and used to determine the levels of PARP, calpastatin, NF-κB p65, inhibitory-κB-α, tumor necrosis factor-α, interleukin-1β, intracellular adhesion molecule-1, inducible nitric oxide synthase, and cyclooxygenase-2. We then measured blood-brain barrier disruption using electron microscopy at 6 and 24 hours after CCI. RESULTS Treatment with PJ34 markedly reduced the extent of both cerebral contusion and edema, improved neurologic scores, and attenuated blood-brain barrier damage resulting from CCI. Our data showed that the cytosolic and nuclear fractions of calpain and NF-κB were up-regulated in the injured cortex and that these changes were reversed by PJ34. Moreover, PJ34 significantly enhanced the calpastatin and inhibitory-κB levels and decreased the levels of inflammatory mediators. CONCLUSIONS PARP inhibition by PJ34 suppresses the overactivation of calpain and the production of inflammatory factors that are caused by NF-κB activation and attenuates neuronal cell death in a mouse model of CCI.

Portable near-infrared rapid detection of intracranial hemorrhage in Chinese population

BACKGROUND Secondary brain injury is the main cause of mortality from traumatic brain injury (TBI). One hallmark of TBI is intracranial hemorrhage, which occurs in 40-50% of severe TBI cases. Early identification of intracranial hematomas in TBI patients allows early surgical evacuation, and can reduce the case-fatality rate of TBI. Since pre-hospital care is the weakest part of Chinese emergency care, there is an urgent need for a capability to detect brain hematomas early. The purpose of this observational study was to evaluate the performance of a near infrared (NIR) based, device to screen for traumatic intracranial hematomas in Chinese population. METHODS Data was collected using the NIR device at the time of a computed tomography (CT) or magnetic resonance imaging (MRI) scan was performed to evaluate a suspected TBI. 85 patients were included in the per protocol population. Of the 85 patients, 45 were determined by CT scan to have intracranial hemorrhage. The CT and MRI scans were read by an independent neuroradiologist who was blinded to the NIR measurements. RESULTS The NIR device demonstrated sensitivity of 95.6% (95% confidence intervals [CI] 83.6-99.2%) and specificity of 92.5% (CI 78.5-98%) in detecting intracranial hematomas larger than 3.5ml in volume, and that were less than 2.5cm from the surface of the brain. CONCLUSION These results confirm in Chinese population the results of previous studies that demonstrated a NIR based device can reliably screen for intracranial hematomas that are likely to be of clinical importance.

Protective Effects of Calpain Inhibition on Neurovascular Unit Injury through Downregulating Nuclear Factor-κB-related Inflammation during Traumatic Brain Injury in Mice

Background: In addition to neurons, all components of the neurovascular unit (NVU), such as glial, endothelial, and basal membranes, are destroyed during traumatic brain injury (TBI). Previous studies have shown that excessive stimulation of calpain is crucial for cerebral injury after traumatic insult. The objective of this study was to investigate whether calpain activation participated in NVU disruption and edema formation in a mouse model of controlled cortical impact (CCI). Methods: One hundred and eight mice were divided into three groups: the sham group, the control group, and the MDL28170 group. MDL28170 (20 mg/kg), an efficient calpain inhibitor, was administered intraperitoneally at 5 min, 3 h, and 6 h after experimental CCI. We then measured neurobehavioral deficits, calpain activity, inflammatory mediator levels, blood–brain barrier (BBB) disruption, and NVU deficits using electron microscopy and histopathological analysis at 6 h and 24 h after CCI. Results: The MDL28170 treatment significantly reduced the extent of both cerebral contusion (MDL28170 vs. vehicle group, 16.90 ± 1.01 mm3 and 17.20 ± 1.17 mm3 vs. 9.30 ± 1.05 mm3 and 9.90 ± 1.17 mm3, both P < 0.001) and edema (MDL28170 vs. vehicle group, 80.76 ± 1.25% and 82.00 ± 1.84% vs. 82.55 ± 1.32% and 83.64 ± 1.25%, both P < 0.05), improved neurological scores (MDL28170 vs. vehicle group, 7.50 ± 0.45 and 6.33 ± 0.38 vs. 12.33 ± 0.48 and 11.67 ± 0.48, both P < 0.001), and attenuated NVU damage resulting (including tight junction (TJ), basement membrane, BBB, and neuron) from CCI at 6 h and 24 h. Moreover, MDL28170 markedly downregulated nuclear factor-&kgr;B-related inflammation (tumor necrosis factor-&agr; [TNF-&agr;]: MDL28170 vs. vehicle group, 1.15 ± 0.07 and 1.62 ± 0.08 vs. 1.59 ± 0.10 and 2.18 ± 0.10, both P < 0.001; inducible nitric oxide synthase: MDL28170 vs. vehicle group, 4.51 ± 0.23 vs. 6.23 ± 0.12, P < 0.001 at 24 h; intracellular adhesion molecule-1: MDL28170 vs. vehicle group, 1.45 ± 0.13 vs. 1.70 ± 0.12, P < 0.01 at 24 h) and lessened both myeloperoxidase activity (MDL28170 vs. vehicle group, 0.016 ± 0.001 and 0.016 ± 0.001 vs. 0.024 ± 0.001 and 0.023 ± 0.001, P < 0.001 and 0.01, respectively) and matrix metalloproteinase-9 (MMP-9) levels (MDL28170 vs. vehicle group, 0.87 ± 0.13 and 1.10 ± 0.10 vs. 1.17 ± 0.13 and 1.25 ± 0.12, P < 0.001 and 0.05, respectively) at 6 h and 24 h after CCI. Conclusions: These findings demonstrate that MDL28170 can protect the structure of the NVU by inhibiting the inflammatory cascade, reducing the expression of MMP-9, and supporting the integrity of TJ during acute TBI.

Clinical Features, Treatment, and Prognostic Factors of 56 Intracranial and Intraspinal Clear Cell Meningiomas

OBJECTIVE Intracranial and intraspinal clear cell meningiomas (CCMs) are rarely reported because of their extremely low incidence, and the current understanding of CCM is poor. The purpose of this study was to analyze the incidence and the clinical, radiologic, pathologic, and prognostic features of intracranial and intraspinal CCMs. METHODS Among 14,310 cases of intracranial and intraspinal meningiomas that were surgically treated between 2006 and 2016 at Beijing Tian Tan Hospital, 56 were chosen for analysis and retrospectively reviewed. To determine which parameters were associated with longer progression-free survival (PFS) and overall survival (OS), statistical analysis was performed. RESULTS CCMs accounted for approximately 0.39% of all intracranial and intraspinal meningiomas. Patients with CCM had a mean age of 32.3 years and there was a female predilection (20 males and 36 females). Gross total resection was achieved in 35 cases, and subtotal resection was achieved in 21 cases. All patients were followed up for 10-206 months after surgery. Twenty-six patients experienced tumor recurrence, and the median PFS was 48.0 months. The 1-year, 3-year, and 5-year PFS was 87.5%, 59.8%, and 41.8%, respectively. Twelve patients died of tumor recurrence, and the median OS was not available. The 1-year, 3-year, and 5-year OS was 98.2%, 91.3%, and 65.8%, respectively. Univariate analysis showed that total tumor removal was significantly associated with a better prognosis. Multivariate analysis confirmed only Simpson grade III and IV resection as an independent risk factor for shorter PFS. Radiotherapy mildly improved PFS after both gross total resection and subtotal resection, showing no significant difference because of the small sample size and short follow-up duration. CONCLUSIONS CCM is a rare subtype of World Health Organization grade II meningioma. CCM typically involves young patients and shows a female predilection and high recurrence rate. When possible, total resection is the primary and most suitable treatment for CCM. For patients with primary tumors, radiotherapy is recommended after the initial operation regardless of the extent of resection. For patients with disease recurrence, secondary surgery combined with radiotherapy might serve as an effective treatment.