Maraviroc promotes recovery from traumatic brain injury in mice by suppression of neuroinflammation and activation of neurotoxic reactive astrocytes

Neuroinflammation and the NACHT,LRR,and PYD domains-containing protein 3 inflammasome play crucial roles in secondary tissue damage following an initial insult in patients with traumatic brain injury(TBI).Maraviroc,a C-C chemokine receptor type 5 antagonist,has been viewed as a new therapeutic strategy for many neuroinflammatory diseases.We studied the effect of maraviroc on TBI-induced neuroinflammation.A moderate-TBI mouse model was subjected to a controlled cortical impact device.Maraviroc or vehicle was injected intraperitoneally 1 hour after TBI and then once per day for 3 consecutive days.Western blot,immunohistochemistry,and TUNEL(terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling)analyses were performed to evaluate the molecular mechanisms of maraviroc at 3 days post-TBI.Our results suggest that maraviroc administration reduced NACHT,LRR,and PYD domains-containing protein 3 inflammasome activation,modulated microglial polarization from M1 to M2,decreased neutrophil and macrophage infiltration,and inhibited the release of inflammatory factors after TBI.Moreover,maraviroc treatment decreased the activation of neurotoxic reactive astrocytes,which,in turn,exacerbated neuronal cell death.Additionally,we confirmed the neuroprotective effect of maraviroc using the modified neurological severity score,rotarod test,Morris water maze test,and lesion volume measurements.In summary,our findings indicate that maraviroc might be a desirable pharmacotherapeutic strategy for TBI,and C-C chemokine receptor type 5 might be a promising pharmacotherapeutic target to improve recovery after TBI.

Kinetochore protein MAD1 participates in the DNA damage response through ataxia-telangiectasia mutated kinase-mediated phosphorylation and enhanced interaction with KU80

Objective:Mitotic arrest-deficient protein 1(MAD1)is a kinetochore protein essential for the mitotic spindle checkpoint.Proteomic studies have indicated that MAD1 is a component of the DNA damage response(DDR)pathway.However,whether and how MAD1 might be directly involved in the DDR is largely unknown.Methods:We ectopically expressed the wild type,or a phosphorylation-site--mutated form of MAD1 in MAD1 knockdown cells to look for complementation effects.We used the comet assay,colony formation assay,immunofluorescence staining,and flow cytometry to assess the DDR,radiosensitivity,and the G2/M checkpoint.We employed co-immunoprecipitation followed by mass spectrometry to identify MAD1 interacting proteins.Data were analyzed using the unpaired Student'st-test.Results:We showed that MAD1 was required for an optimal DDR,as knocking down MAD1 resulted in impaired DNA repair and hypersensitivity to ionizing radiation(IR).We found that IR-induced serine 214 phosphorylation was ataxia-telangiectasia mutated(ATM)kinase-dependent.Mutation of serine 214 to alanine failed to rescue the phenotypes of MAD1 knockdown cells in response to IR.Using mass spectrometry,we identified a protein complex mediated by MAD1 serine 214 phosphorylation in response to IR.Among them,we showed that KU80 was a key protein that displayed enhanced interaction with MAD1 after DNA damage.Finally,we showed that MAD1 interaction with KU80 required serine 214 phosphorylation,and it was essential for activation of DNA protein kinases catalytic subunit(DNA-PKcs).Conclusions:MAD1 serine 214 phosphorylation mediated by ATM kinase in response to IR was required for the interaction with KU80 and activation of DNA-PKCs.

Could Intrathymic Injection of Myelin Basic Protein Suppress Inflammatory Response After Co-culture of T Lymphocytes and BV-2 Microglia Cells？

Background： The interaction between activated microglia and T lymphocytes can yield abundant pro-inflammatory cytokines. Our previous study proved that thymus immune tolerance could alleviate the inflammatory response. This study aimed to investigate whether intrathymic injection of myelin basic protein （MBP） in mice could suppress the inflammatory response after co-culture ofT lymphocytes and BV-2 microglia cells. Methods： Totally, 72 male C57BL/6 mice were randomly assigned to three groups （17 - 24 in each）： Group A： intrathymic injection of 100 μl M BP （1 mg/ml）; Group B： intrathymic injection of 100 μ1 phosphate-buffered saline （PBS）; and Group C： sham operation group. Every eight mice in each group were sacrificed to obtain the spleen at postoperative days 3, 7, and 14, respectively. T lymphocytes those were extracted and purified from the spleens were then co-cultured with activated BV-2 microglia cells at a proportion of 1：2 in the medium containing MBP for 3 days. After identified the T lymphocytes by CD3, surface antigens oft lymphocytes （CD4, CD8, CD152, and CD154） and BV-2 microglia cells （CD45 and CD54） were detected by flow cytometry. The expressions of pro-inflammatory factors of BV-2 microglia cells （interleukin [1L]- 1β, tumor necrosis factor-o~ [TNF-α], and inducible nitric oxide synthase [iNOS]） were detected by quantitative real-time polymerase chain reaction （PCR）. One-way analysis of variance （ANOVA） and the least significant difference test were used for data analysis. Results： The levels of CD152 in Group A showed an upward trend from the 3rd to 7th day, with a downward trend from the 7th to 14th day （20.12 ± 0.71%, 30.71 ± 1.14%, 13.50 ± 0.71% at postoperative days 3, 7, and 14, respectively, P 〈 0.05）. The levels of CD 154 in Group A showed a downward trend from the 3ra to 7th day, with an upward trend from the 7th to 14th day （1 0.00± 0.23%, 5.28 ±0.69%, 14.67 ± 2.71% at postoperative days 3, 7, and 14, respectively, P 〈 0.05）. The ratio ofCD4＋/CD8 ＋ T in Group A showed a downward trend from the 3rd to 7th day, with the minimum at postoperative day 7, then an upward trend from the 7th to 14th day （P 〈 0.05）. Meanwhile, the levels of CD45 and CD54 in Group A were found as the same trend as the ratio of CD4＋/CD8 ＋ T （CD45：83.39 ± 2.56%, 82.74± 2.09%, 87.56 ± 2. 11%： CD54：3.80 ± 0.24%, 0.94 ± 0.40%, 3.41 ± 0.33% at postoperative days 3, 7, and 14, respectively, P 〈 0.05）. The expressions of TNF-α, IL- 1 β, and iNOS in Group A were significantly lower than those in Groups B and C, and the values at postoperative day 7 were the lowest compared with those at postoperative days 3 and 14 （P 〈 0.05）. No significant difference was found between Groups B and C. Conclusions： l ntrathymic injection of MBP could suppress the immune reaction that might reduce the secondary immune injury of brain tissue induced by an inflammatory response.

Quantified assessment of deep brain stimulation on Parkinson’s patients with task fNIRS measurements and functional connectivity analysis:a pilot study

Background:Deep brain stimulation(DBS)has proved effective for Parkinson’s disease(PD),but the identification of stimulation parameters relies on doctors’subjective judgment on patient behavior.Methods:Five PD patients performed 10-meter walking tasks under different brain stimulation frequencies.During walking tests,a wearable functional near-infrared spectroscopy(fNIRS)system was used to measure the concentration change of oxygenated hemoglobin(ΔHbO_(2))in prefrontal cortex,parietal lobe and occipital lobe.Brain functional connectivity and global efficiency were calculated to quantify the brain activities.Results:We discovered that both the global and regional brain efficiency of all patients varied with stimulation parameters,and the DBS pattern enabling the highest brain efficiency was optimal for each patient,in accordance with the clinical assessments and DBS treatment decision made by the doctors.Conclusions:Task fNIRS assessments and brain functional connectivity analysis promise a quantified and objective solution for patient-specific optimization of DBS treatment.Trial registration:Name:Accurate treatment under the multidisciplinary cooperative diagnosis and treatment model of Parkinson’s disease.Registration number is ChiCTR1900022715.Date of registration is April 23,2019.

Case Reports of a Giant Cell Reparative Granuloma and a Giant Cell Tumor on Temporal Bone

To the Editor： Giant cell reparative granuloma （GCRG） is a nonneoplastic, benign lesion derived from bone tissue. The morbidity of GCRG is relatively low, comprising approximately 7% of benign bone lesions. GCRGs are mostly tbund in adolescents, and no apparent gender inclination has been identified. In addition, GCRGs are predominantly found in the mandible and maxilla; a few cases have occurred in the short bones as the hands and feet. Occasionally, GCRGs are detected in long bones and vertebrae; temporal GCRGs are rarely reported. GCRGs associated with intracranial invasion are rare. Although some cases of GCRG have been previously reported, characteristic and elaborate descriptions have not yet been clearly established for imaging diagnosis and differential diagnosis. This article reported one case of left temporal GCRG associated with cholesteatoma caused by otitis media mastoiditis and another case of temporal giant cell tumor （GCT）.

Immune Tolerance Therapy： A New Method for Treatment of Traumatic Brain Injury

Objective： Due to the special anatomical structure and pathophysiological mechanism of the central nervous system （CNS）, there is a big difference between the repair of brain injury and other systems of the body. More and more evidence shows that targetedly reducing the autoimmune response of brain tissue without affecting the immune function in other parts of the body will be the best optimized treatment for brain injury. Data Sources： This review was based on data in articles published in PubMed up to June 5,2017, with the following keywords： ＂immune tolerance＂, ＂traumatic brain injury＂, and ＂central nervous system＂. Study Selection： Original articles and critical reviews on immune tolerance and brain damage were selected for this review. References of the retrieved articles were also screened to search for potentially relevant papers. Results： The CNS is isolated from the immune system through the blood-brain barrier. After brain injury, brain antigens are released into the systemic circulation to induce damaging immune responses. Immune tolerance can effectively reduce the brain edema and neurological inflammatory response after brain injury, which is beneficial to the recovery of neurological function. The clinical application prospect and theoretical research value of the treatment of immune tolerance on traumatic brain inj ury （TBi） is worth attention. Conclusions： The establishment of immune tolerance mechanism has a high clinical value in the treatment of TBI. It opens up new opportunities for the treatment of brain damage.