Dopamine D2 receptor on CD4+ T cells is protective against inflammatory responses and signs in a mouse model of rheumatoid arthritis.

BACKGROUND: Dopamine is a neurotransmitter and has been found to regulate lymphocytes by acting on dopamine receptors (DRs). CD4+ T cells express all the five subtypes of DRs, D1R to D5R. Although CD4+ T cells have been involved in pathogenesis of rheumatoid arthritis (RA), roles of DRs expressed on these cells in RA are poorly understood. This study determined whether D2R expressed on CD4+ T cells regulates inflammatory responses and signs in collagen type II (CII)-induced arthritis (CIA), a mouse model of RA. METHODS: DBA/1 mice and C57BL/6 mice with global D1r or D2r deficiency (D1r-/- or D2r-/-) or CD4+ T cell-specific D2r deletion (D2rfl/fl/CD4Cre) were used to prepare CIA model by intradermal injection of CII. D2R agonist sumanirole was intraperitoneally administered in CIA mice. CD4+ T cells obtained from CIA mice were exposed to sumanirole or/and D2R antagonist L-741,626 in vitro. Arthritic symptoms were assessed by clinical arthritis scores. Flow cytometric assay measured frequencies of CD4+ T cell subsets (Th1, Th2, Th17 and Treg cells). Expression of specific transcription factors for the CD4+ T cell subsets was tested by Western blot. Cytokine production was estimated by quantitative PCR and ELISA. RESULTS: CIA mice manifested a bias of CD4+ T cells towards Th1 and Th17 cells. D2r-/- CIA mice showed a stronger bias towards Th1 and Th17 phenotypes than CIA mice, while D1r-/- CIA mice did not show the changes. CD4+ T cell-specific D2r deletion exacerbated both the polarization towards Th1 and Th17 cells and the symptoms of arthritis. Sumanirole administration in CIA mice ameliorated the bias of CD4+ T cells towards Th1 and Th17 phenotypes as well as arthritic symptoms. Sumanirole treatment of in vitro CD4+ T cells obtained from CIA mice promoted the shift to Treg cells, and the effect of sumanirole was blocked by L-741,626. CONCLUSIONS: D2R expressed on CD4+ T cells is protective against imbalance between pro-inflammatory and anti-inflammatory T cells and arthritic symptoms in CIA.

Activation of ß2-adrenergic Receptor Alleviates Collagen-induced Arthritis by Ameliorating Th17/Treg Imbalance.

Background: Recent research in our laboratory shows that CD4+ T cells express the ß2 adrenergic receptor (ß2-AR), and the sympathetic neurotransmitter norepinephrine regulates the function of T cells via ß2-AR signaling. However, the immunoregulatory effect of ß2-AR and its related mechanisms on rheumatoid arthritis is unknown. Objective: To explore the effects of ß2-AR in collagen-induced arthritis (CIA) on the imbalance of T helper (Th) 17/ regulatory T (Treg) cells. Methods: In DBA1/J mice, collagen type II was injected intradermally at the tail base to prepare the CIA model. The specific ß2-AR agonist, terbutaline (TBL), was administered intraperitoneally beginning on day 31 and continuing until day 47 after primary vaccination, twice a day. Magnetic beads were used to sort CD3+ T cells subsets from spleen tissues. Results: In vivo, ß2-AR agonist TBL alleviated arthritis symptoms in the CIA mice including histopathology of the ankle joints, four limbs' arthritis score, the thickness of ankle joints, and rear paws. After TBL treatment, in the ankle joints, the levels of proinflammatory factors (IL-17/22) notably decreased and the levels of immunosuppressive factors (IL-10/TGF-ß) significantly increased. In vitro, ROR-γt protein expression, Th17 cell number, mRNA expression and the releasing of IL-17/22 from CD3+ T cells reduced following TBL administration. Moreover, TBL enhanced the anti-inflammatory responses of Treg cells. Conclusion: These results suggest that ß2-AR activation exerts anti-inflammatory effects through the amelioration of Th17/Treg imbalance in the CIA disease.

Interleukin 17A deficiency alleviates neuroinflammation and cognitive impairment in an experimental model of diabetic encephalopathy.

Interleukin 17A (IL-17A) was previously shown to be a key pro-inflammatory factor in diabetes mellitus and associated complications. However, the role of IL-17A in diabetic encephalopathy remains poorly understood. In this study, we established a mouse model of diabetic encephalopathy that was deficient in IL-17A by crossing Il17a-/- mice with spontaneously diabetic Ins2Akita (Akita) mice. Blood glucose levels and body weights were monitored from 2-32 weeks of age. When mice were 32 weeks of age, behavioral tests were performed, including a novel object recognition test for assessing short-term memory and learning and a Morris water maze test for evaluating hippocampus-dependent spatial learning and memory. IL-17A levels in the serum, cerebrospinal fluid, and hippocampus were detected with enzyme-linked immunosorbent assays and real-time quantitative polymerase chain reaction. Moreover, proteins related to cognitive dysfunction (amyloid precursor protein, ß-amyloid cleavage enzyme 1, p-tau, and tau), apoptosis (caspase-3 and -9), inflammation (inducible nitric oxide synthase and cyclooxygenase 2), and occludin were detected by western blot assays. Pro-inflammatory cytokines including tumor necrosis factor-α, interleukin-1ß, and interferon-γ in serum and hippocampal tissues were measured by enzyme-linked immunosorbent assays. Microglial activation and hippocampal neuronal apoptosis were detected by immunofluorescent staining. Compared with that in wild-type mice, mice with diabetic encephalopathy had higher IL-17A levels in the serum, cerebrospinal fluid, and hippocampus; downregulation of occludin expression; lower cognitive ability; greater loss of hippocampal neurons; increased microglial activation; and higher expression of inflammatory factors in the serum and hippocampus. IL-17A knockout attenuated the abovementioned changes in mice with diabetic encephalopathy. These findings suggest that IL-17A participates in the pathological process of diabetic encephalopathy. Furthermore, IL-17A deficiency reduces diabetic encephalopathy-mediated neuroinflammation and cognitive defects. These results highlight a role for IL-17A as a mediator of diabetic encephalopathy and potential target for the treatment of cognitive impairment induced by diabetic encephalopathy.

[Effects of α1-adrenoreceptor on Treg cell function in collagen-induced arthritis].

Objective: An animal model of collagen-induced arthritis (CIA) was used to investigate the effects of norepinephrine (NE) and α1-adrenoreceptor (α1-AR) on Treg cells in CIA. Methods: Thirty-two male DBA/1 mice were randomly divided into control group and CIA model group. CIA was prepared by intradermal injection of collagen type II (CII, 100 µl) at the tail base of DBA/1 mice. On the 41th day following primary immunization, co-expression of CD4+T and α1-AR in mouse spleens was observed. Protein expressions of α1-AR in the ankle joints and the spleens of mice were measured by Western blot analysis. The CD4+ T cells were isolated from the mouse spleen tissues in CIA mice and treated with NE or α1-AR agonist phenylephrine. Percentage of Treg cells in mouse CD4+ T cells of CIA mice was determined by flow cytometry. Expressions of α1-AR, transforming growth factor-ß (TGF-ß) and IL-10 in CD4+T cells of CIA mice were assessed by Western blot. Results: Co-expression of CD4 and α1-AR was observed in spleens of both intact and CIA mice. Compared with intace mice, α1-AR expressions in the ankle joints and spleens were down-regulated in CIA mice. NE increased the function of Treg cells in CD4+ T cells of CIA mice compared with that of nothing-treated CD4+T cells of CIA mice. Moreover, the α1-AR agonist phenylephrine increased the Treg cell function in CD4+ T cells of CIA mice relative to that of nothing-treated CD4+T cells of CIA mice. Conclusion: Activating α1-AR on CD4+T cells of CIA mice enhances Treg cell function,facilitating a shift of CD4+T cells toward Treg polarization.

Dopamine receptor D2 on CD4+ T cells is protective against neuroinflammation and neurodegeneration in a mouse model of Parkinson's disease.

Parkinson's disease (PD) is a chronic neurodegenerative disease. Recently, neuroinflammation driven by CD4+ T cells has been involved in PD pathophysiology. Human and murine lymphocytes express all the five subtypes of dopamine receptors (DRs), DRD1 to DRD5. However, roles of DRs particularly DRD2 expressed on CD4+ T cells in PD remain elucidated. Global Drd1- or Drd2-knockout (Drd1-/- or Drd2-/-) mice or CD4+ T cell-specific Drd2-knockout (Drd2fl/fl/CD4Cre) mice were intraperitoneally injected with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) to induce PD with the different mutants. On the 7th day following MPTP injection, mice were assessed for dopaminergic neurodegeneration, locomotor impairments, microglial activation, as well as CD4+ T-cell differentiation and function. Furthermore, in vitro CD4+ T cells were exposed to DRD2 agonist and antagonist and then differentiation and function of the cells were determined. MPTP induced dopaminergic neuronal loss in the nigrostriatal system, motor coordinative and behavioral impairments, microglial activation, and CD4+ T-cell polarization to pro-inflammatory T-helper (Th)1 and Th17 phenotypes. Importantly, either Drd2-/- or Drd2fl/fl/CD4Cre mice manifested more severe dopaminergic neurodegeneration, motor deficits, microglial activation, and CD4+ T-cell bias towards Th1 and Th17 phenotypes in response to MPTP, but Drd1-/- did not further alter MPTP intoxication. DRD2 agonist sumanirole inhibited shift of CD4+ T cells obtained from MPTP-intoxicated mice to Th1 and Th17 phenotypes and DRD2 antagonist L-741,626 reversed sumanirole effects. These findings suggest that DRD2 expressed on CD4+ T cells is protective against neuroinflammation and neurodegeneration in PD. Thus, developing a therapeutic strategy of stimulating DRD2 may be promising for mitigation of PD.

Intervention of Tyrosine Hydroxylase Expression Alters Joint Inflammation and Th17/Treg Imbalance in Collagen-Induced Arthritis.

BACKGROUND/AIMS: Neuroendocrine dysregulation has been associated with rheumatoid arthritis (RA). Tyrosine hydroxylase (TH), a rate-limiting enzyme for synthesis of neuroendocrine hormones such as epinephrine, is also expressed in T lymphocytes and regulates balance between helper T (Th) 17 cells and regulatory T (Treg) cells. Herein, we aimed to show that TH expression in joints alleviates joint inflammation and Th17/Treg imbalance in collagen-induced arthritis (CIA), an animal model of RA, and these effects may be implemented by the mechanism of epinephrine action on α1-adrenoreceptor (α1-AR) in T cells. METHODS: CIA was prepared by intradermal injection of collagen type II in tail base of DBA1/J mice. On the 33rd day post-immunization, lentiviral vectors encoding TH or TH shRNA were injected into ankle joints of CIA mice. Limb inflammation of the mice was assessed beginning from day 21 until day 69 post-immunization by measurement of limb swelling, erythema and rigidity. Th17 and Treg differentiation and function in ankle joints were assessed on day 69 post-immunization by test of the expression of Th17 transcriptional factor ROR-γt and the levels of proinflammatory cytokines interleukin (IL)-17 and IL-22 as well as the expression of Treg transcriptional factor Foxp3 and the levels of antiinflammatory cytokines transforming growth factor (TGF)-ß1 and IL-10. T cells were obtained from the spleen of mice that had been immunized with collagen type II 41 day earlier and treated with epinephrine or α1-AR agonist phenylephrine in vitro. Flow cytometry was used to analyze the percentages of CD25-IL-17+ cells and CD25+Foxp3+ cells in CD4+ T cells. RESULTS: TH gene overexpression in ankle joints of CIA mice reduced limb inflammation and Th17-related transcription factor expression and inflammatory cytokine production but increased Treg-related antiinflammatory cytokine production in the joints. In contrast, TH gene silence in ankle joints of CIA mice enhanced limb inflammation and Th17 cell activity but decreased Treg cell function in the joints. Epinephrine upregulated α1-AR expression in T cells derived from CIA mice. Both epinephrine and phenylephrine reduced CIA-induced Th17 transcription factor expression and inflammatory cytokine production but enhanced Treg antiinflammatory cytokine production in vitro. CONCLUSION: Upregulating TH expression in joints alleviates joint inflammation and Th17/Treg imbalance in CIA at least partially by enhancing epinephrine action on α1-AR in T cells.

Psychoneuroimmunology goes East: Development of the PNIRSChina affiliate and its expansion into PNIRSAsia-Pacific.

The Psychoneuroimmunology Research Society (PNIRS) created an official Chinese regional affiliate in 2012, designated PNIRSChina. Now, just eight years later, the program has been so successful in advancing the science of psychoneuroimmunology that it has expanded to the whole of Asia-Oceania. In 2017, PNIRSChina became PNIRSAsia-Pacific. Between 2012 and 2019, this outreach affiliate of PNIRS organized seven symposia at major scientific meetings in China as well as nine others in Taiwan, Japan, South Korea, Australia and New Zealand. This paper summarizes the remarkable growth of PNIRSAsia-Pacific. Here, regional experts who have been instrumental in organizing these PNIRSAsia-Pacific symposia briefly review and share their views about the past, present and future state of psychoneuroimmunology research in China, Taiwan, Australia and Japan. The newest initiative of PNIRSAsia-Pacific is connecting Asia-Pacific laboratories with those in Western countries through a simple web-based registration system. These efforts not only contribute to the efforts of PNIRS to serve a truly global scientific society but also to answer the imperative call of increasing diversity in our science.

TGF-ß1 Provides Neuroprotection via Inhibition of Microglial Activation in 3-Acetylpyridine-Induced Cerebellar Ataxia Model Rats.

Cerebellar ataxias (CAs) consist of a heterogeneous group of neurodegenerative diseases hallmarked by motor deficits and deterioration of the cerebellum and its associated circuitries. Neuroinflammatory responses are present in CA brain, but how neuroinflammation may contribute to CA pathogenesis remain unresolved. Here, we investigate whether transforming growth factor (TGF)-ß1, which possesses anti-inflammatory and neuroprotective properties, can ameliorate the microglia-mediated neuroinflammation and thereby alleviate neurodegeneration in CA. In the current study, we administered TGF-ß1 via the intracerebroventricle (ICV) in CA model rats, by intraperitoneal injection of 3-acetylpyridine (3-AP), to reveal the neuroprotective role of TGF-ß1. The TGF-ß1 administration after 3-AP injection ameliorated motor impairments and reduced the calbindin-positive neuron loss and apoptosis in the brain stem and cerebellum. Meanwhile, 3-AP induced microglial activation and inflammatory responses in vivo, which were determined by morphological alteration and an increase in expression of CD11b, enhancement of percentage of CD40 + and CD86 + microglial cells, upregulation of pro-inflammatory mediators, tumor necrosis factor (TNF)-α and interleukin (IL)-1ß, and a downregulation of neurotrophic factor, insulin-like growth factor (IGF)-1 in the brain stem and cerebellum. TGF-ß1 treatment significantly prevented all the changes caused by 3-AP. In addition, in vitro experiments, TGF-ß1 directly attenuated 3-AP-induced microglial activation and inflammatory responses in primary cultures. Purkinje cell exposure to supernatants of primary microglia that had been treated with TGF-ß1 reduced neuronal loss and apoptosis induced by 3-AP-treated microglial supernatants. Furthermore, the protective effect was similar to those treated with TNF-α-neutralizing antibody. These findings suggest that TGF-ß1 protects against neurodegeneration in 3-AP-induced CA rats via inhibiting microglial activation and at least partly TNF-α release.

Treg Cells Attenuate Neuroinflammation and Protect Neurons in a Mouse Model of Parkinson's Disease.

Regulatory T cells (Tregs), which secrete transforming growth factor (TGF)-ß and interleukin (IL)-10, have essential role in anti-inflammatory and neurotrophic functions. Herein, we explore the neuroprotection of Tregs in Parkinson's disease (PD) by adoptive transfer of Tregs. Tregs, isolated by magnetic sorting, were activated in vitro and then were adoptively transferred to 1-methyl-4-phenyl-1,2,3,6- tetrahydropyridine (MPTP)-treated mice. Neuroinflammation, dopaminergic neuronal loss and behavioral changes of PD mice were evaluated. Live cell imaging system detected a dynamic contact of Tregs with MN9D cells that were stained with CD45 and galectin-1, respectively. Tregs prevented MPTP-induced dopaminergic neuronal loss, behavioral changes, and attenuated the inflammatory reaction in the brain. When blockade the LFA-1 activity in Tregs or the ICAM-1 activity in endothelial cells, the percentage of Tregs in substantia nigra (SN) decreased. CD45 and galectin-1 were expressed by Tregs and MN9D cells, respectively. CD45-labeled Tregs dynamically contacted with galectin-1-labeled MN9D cells. Inhibiting CD45 in Tregs impaired the ability of Tregs to protect dopaminergic neurons against MPP+ toxicity. Similarly, galectin-1 knockdown in MN9D cells reduced the ability of Tregs neuroprotection. Adoptive transfer of Tregs protects dopaminergic neurons in PD mice by a cell-to-cell contact mechanism underlying CD45-galectin-1 interaction. Graphical Abstract.

IL-17A exacerbates neuroinflammation and neurodegeneration by activating microglia in rodent models of Parkinson's disease.

Neuroinflammation has been involved in pathogenesis of Parkinson's disease (PD), a chronic neurodegenerative disease characterized neuropathologically by progressive dopaminergic neuronal loss in the substantia nigra (SN). We recently have shown that helper T (Th)17 cells facilitate dopaminergic neuronal loss in vitro. Herein, we demonstrated that interleukin (IL)-17A, a proinflammatory cytokine produced mainly by Th17 cells, contributed to PD pathogenesis depending on microglia. Mouse and rat models for PD were prepared by intraperitoneal injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) or striatal injection of 1-methyl-4-phenylpyridinium (MPP+), respectively. Both in MPTP-treated mice and MPP+-treated rats, blood-brain barrier (BBB) was disrupted and IL-17A level increased in the SN but not in cortex. Effector T (Teff) cells that were adoptively transferred via tail veins infiltrated into the brain of PD mice but not into that of normal mice. The Teff cell transfer aggravated nigrostriatal dopaminergic neurodegeneration, microglial activation and motor impairment. Contrarily, IL-17A deficiency alleviated BBB disruption, dopaminergic neurodegeneration, microglial activation and motor impairment. Anti-IL-17A-neutralizing antibody that was injected into lateral cerebral ventricle in PD rats ameliorated the manifestations mentioned above. IL-17A activated microglia but did not directly affect dopaminergic neuronal survival in vitro. IL-17A exacerbated dopaminergic neuronal loss only in the presence of microglia, and silencing IL-17A receptor gene in microglia abolished the IL-17A effect. IL-17A-treated microglial medium that contained higher concentration of tumor necrosis factor (TNF)-α facilitated dopaminergic neuronal death. Further, TNF-α-neutralizing antibody attenuated MPP+-induced neurotoxicity. The findings suggest that IL-17A accelerates neurodegeneration in PD depending on microglial activation and at least partly TNF-α release.

Acetylcholine suppresses microglial inflammatory response via α7nAChR to protect hippocampal neurons.

Neuroinflammation is principally linked to glial function and has been demonstrated to participate in the pathogenesis of Alzheimer's disease, a neurodegenerative disorder characterized by beta-amyloid ccumulation and neurotransmission disruption. Previous findings suggest acetylcholine exerts anti-inflammatory and neuroprotective properties in several neurodegenerative disorders. However, the underlying mechanisms remain elusive. Here evaluation of the influence of acetylcholine on neuroinflammation and neurodegeneration in Alzheimer's disease is reported and further neuroprotective mechanisms are investigated. Investigation of microglia in lipopolysaccharide-induced hippocampal neuronal toxicity employed α7nAChR gene silencing and demonstrated that both the anti-inflammatory and neuroprotective effects of acetylcholine rely on α7nAChR pathways. As expected, in neuron-microglia co-cultures lipopolysaccharide induced an increase in expression of pro-inflammatory factors, including inducible nitric oxide synthase, interleukin-1α, and tumor necrosis factor-α, and decreased expression of neurotrophic factors such as insulin-like growth factor-1, and neuronal apoptosis. Acetylcholine protects against lipopolysaccharide-elicited neuronal injury by inhibiting the microglial inflammatory response and promoting microglial neurotrophic factor production via the action of α7nAChR on microglia. These findings establish that ACh activates α7nAChR in microglia, which in turn protects hippocampal neurons.

The intra-neuroendoscopic technique (INET): a modified minimally invasive technique for evacuation of brain parenchyma hematomas.

Background: Minimally invasive endoscopic hematoma evacuation is widely used in the treatment of intracerebral hemorrhage. However, this technique still has room for improvement. The intra-neuroendoscopic technique (INET) is a modified minimally invasive technique, and we report its safety and efficacy in evacuating brain parenchyma hematomas by comparing it with cranial puncture and drainage operation (CPDO). Methods: The frontal, temporal, or occipital approaches were used according to the site of bleeding. The preoperative and postoperative hematoma volumes, Glasgow Coma Scale (GCS) score, Cerebral State Index (CSI), hematoma evacuation rate, operation time, complications, and 30-day mortality and Glasgow Outcome Scale (GOS) were retrospectively compared between the two groups. Results: A total of 98 patients were enrolled. The evacuation rate (84 ± 7.1% versus 51.0 ± 8.4%, p = 0.00), 7-day GCS (11.8 ± 1.2 versus 10.4 ± 1.5, p = 0.01), and CSI (87.1 ± 8.7 versus 80.6 ± 10.2, p = 0.02) were higher, and the 30-day mortality rate (1.9% versus 15.6%, p = 0.036) was lower in the INET group. However, the operation time was longer in the INET group than in the control group (65.2 ± 12.5 min versus 45.6 ± 10.9 min, p = 0.000). Multivariable logistic regression showed that a good medium-term outcome (GOS scores 4-5) was significantly associated with INET (odds ratio (OR) 3.514, 95% confidence interval (CI) 1.463-8.440, p = 0.005), age under 65 years (OR 1.402, 95% CI, 1.041-1.888, p = 0.026), and hematoma volume less than 50 ml (OR 1.974, 95% CI 1.302-2.993, p = 0.001). Conclusions: INET surgery for brain parenchyma hematoma evacuation is a safe and efficient modified technique. This technique is minimally invasive, has less complications, and may be helpful in providing optimal outcomes for selected patients. Trial registration: ClinicalTrials.gov, NCT02515903. Registered on 5 August 2015.

Delayed treatment of α5 GABAA receptor inverse agonist improves functional recovery by enhancing neurogenesis after cerebral ischemia-reperfusion injury in rat MCAO model.

Development of effective therapeutics and treatment strategy to promote recovery after cerebral ischemia-reperfusion injury necessitates further understandings of the complex pathophysiology of ischemic stroke. Given that α5-GABAAR inhibition has been shown to be involved in functional recovery after stroke, the present study was designed to evaluate the effects of treatment timing of α5 GABAAR inhibition on post-middle cerebral artery occlusion (MCAO) functional recovery. To this end, we examined the effects of L655,708 (α5 GABAAR inverse agonist) treatment at 3 or 7 days post-ischemia on apoptosis and neurogenesis in the peri-infarct region, brain infarction size, as well as modified neurological severity score (mNSS) and rotarod test time in rats. Consistent with previous reports, we found that when the treatment of L655,708 was initiated at post-MCAO day 3, it did not alter the functional recovery in rats. However, when the treatment of L655,708 was initiated at post-MCAO day 7, it demonstrated beneficial effects on functional recovery in rats. Interestingly, this phenomenon was not associated with altered brain infarction size nor with changes in brain cell apoptosis. However, we found that delayed treatment of L655,708 at post-MCAO day 7 significantly increased neurogenesis in peri-infarct zone in rats. These results suggested that removing α5 GABAAR-mediated tonic inhibition after cerebral ischemia-reperfusion injury may be an effective therapeutic strategy for promoting functional recovery from stroke.

A new modified neuroendoscope technology to remove severe intraventricular haematoma.

BACKGROUND: Minimally invasive endoscopic haematoma evacuation is widely used in the treatment of intraventricular haemorrhage. However, its technique still has room for improvement. A new modified neuroendoscope technology (MNT) was used in this study and we explored its safety and efficacy in the treatment of severe acute intraventricular haemorrhage by comparing it with extraventricular drainage plus urokinase thrombolytic (EVD + UT) therapy. METHODS: The following parameters were compared between the MNT group and the control group: incision design, operation time, ICU monitoring time, ventricular drainage tube (VDT) placement time, post-operative drainage tube obstruction (PDTO) rate, post-operative complications rate, 6-month mortality and Glasgow Outcome Scale (GOS). RESULTS: A total of 85 patients were enrolled. The ICU monitoring times, VDT placement times, PDTO rate were shorter in the MNT group. Multivariable logistic regression identified that good medium-term outcome (GOS scores 4-5) was significantly associated with MNT applied (OR 1.017, 95% CI 1.005-1.029, p = 0.008), age under 65 years (OR 4.223, 95% CI, 1.322-17.109, p = 0.034) and pre-operation GCS scores more than 10 (OR 3.427, 95% CI 1.048-11.205, p = 0.040). CONCLUSION: MNT surgery for severe intraventricular haematoma evacuation is a safe and efficient new surgical option. This technique is minimally invasive and may be helpful to provide good outcomes for selected patients.

The intra-neuroendoscopic technique: A new method for rapid removal of acute severe intraventricular hematoma.

The mortality rate of acute severe intraventricular hematoma is extremely high, and the rate of disability in survivors is high. Intraventricular hematoma has always been a difficult problem for clinical treatment. Although minimally invasive endoscopic hematoma evacuation is widely used to treat this disease, the technique still has room for improvement. Equipment for the intra-neuroendoscopic technique (INET) consists of two of our patented inventions: a transparent sheath (Patent No. ZL 200820046232.0) and a hematoma aspirator (Patent No. ZL 201520248717.8). This study explored the safety and efficacy of INET by comparing it with extraventricular drainage in combination with urokinase thrombolytic therapy. This trial recruited 65 patients with severe intraventricular hemorrhage, including 35 (19 men and 16 women, aged 53.2 ± 8.7 years) in the INET group and 30 (17 men and 13 women, aged 51.5 ± 7.9 years) in the control group (extraventricular drainage plus urokinase thrombolytic therapy). Our results showed that compared with the control group, the INET group exhibited lower intraventricular hemorrhage volumes, shorter intensive care-unit monitoring and ventricular drainage-tube placement times, and fewer incidences of intracranial infection, secondary bleeding, and mortality. Thus, the prognosis of survivors had improved remarkably. These findings indicate that INET is a safe and efficient new method for treating severe intraventricular hematoma. This trial was registered with ClinicalTrials.gov (NCT02515903).

[Acetylcholine suppresses microglial inflammatory response in rats via acting on microglial α7nAChR].

Microglia are the main immune cells in the central nervous system. In the present study, the mechanism for acetylcholine (ACh) inhibiting microglial inflammatory response was investigated. Primary culture of microglia was isolated from cerebral cortex of Sprague-Dawley (SD) rats. Lipopolysaccharide (LPS) was used to activate the microglia to induce inflammatory response, and then the microglia were treated with ACh for 24 h. Protein expressions of several inflammatory factors, insulin-like growth factor 1 (IGF-1) and α7 nicotinic acetylcholine receptor (α7nAChR) were detected by Western blot. Release of inflammatory factors and IGF-1 into media was detected by ELISA. After α7nAChR gene silence was achieved by lentivirus-transfection of α7nAChR-shRNA, the change of ACh effect was observed. The results showed that LPS induced microglial activation, up-regulated inducible nitric oxide synthase (iNOS) protein expression, increased the expressions and release of IL-1ß and TNF-α, and decreased the expression and release of the neurotrophic factor, IGF-1. ACh could reverse these effects of LPS. Meanwhile, LPS reduced the protein expression of α7nAChR on the microglial cells, whereas ACh could reverse the effect. Silencing of α7nAChR gene in microglia abolished the ability of ACh to inhibit LPS-induced inflammatory responses. These results suggest that ACh exerts its protection against LPS-induced microglial inflammation via acting on α7nAChR on microglia, which may provide a novel target for the treatment of neuro-inflammatory diseases.

Norepinephrine Inhibits Th17 Cells via ß2-Adrenergic Receptor (ß2-AR) Signaling in a Mouse Model of Rheumatoid Arthritis.

BACKGROUND Norepinephrine (NE), a neurotransmitter released from the sympathetic nerves, has been shown to be involved in rheumatoid arthritis (RA). However, its role in the sympathetic nervous system in RA is divergent. Herein, we demonstrate that the sympathetic neurotransmitter NE exerts an anti-inflammatory effect in collagen-induced arthritis (CIA), a mouse model of RA, by inhibiting Th17 cell differentiation and function via ß2-adrenergic receptor (ß2-AR) signaling. MATERIAL AND METHODS CIA was prepared by intradermal injection of collagen type II in the tail base of DBA1/J mice. On the 41st day post-immunization, the mice were used as CIA models. CD4+ T cells from the spleen were purified using magnetic cell sorting and activated with anti-CD3 anti-CD28 antibodies. Th17 cells were polarized from the CD4+ T cells using various antibodies and cytokines. RESULTS Co-expression of CD4 and ß2-AR was observed in spleens of both intact and CIA mice. The ß2-AR expression in the ankle and spleen was downregulated in CIA mice. CIA induced increases in production of interleukin (IL)-17 and IL-22, CD25-IL-17+ cell percentage, and ROR-γt expression in CD4+ T cells. Importantly, NE reduced the CIA-induced CD4+ T cell shift towards Th17 phenotype, and the ß2-AR antagonist ICI118551 blocked the NE effect. Moreover, the ß2-AR agonist terbutaline (Terb) inhibited CIA-induced CD4+ T cell proliferation and shift towards Th17 phenotype, and the protein kinase A (PKA) inhibitor H-89 abolished the agonist effect. Terb also reduced CIA-induced Th17 enhancement, and H-89 impaired the Terb effect. CONCLUSIONS NE inhibits Th17 cell differentiation and function in CIA condition by activation of ß2-AR/PKA signaling.

[Effects of TGF-ß1 on the expression and secretion of cytokines induced by Aß1-42 in hippocampal neuron and microglia co-cultures].

OBJECTIVE: To investigate the neuroprotective effects of transforming growth factor beta 1(TGF-ß1) on the expression and secretion of cytokines induced by Aß1-42 in hippocampal neurons and microglial co-cultures. METHODS: Hippocampal neurons and microglia obtained from SD rat were co-cultured. TGF-ß1 was applied on day 5 after the neurons and microglia co-cultures were incubated at the concentrations of 5 or 20 ng/ml, Aß1-42 was added 1 h following TGF-ß1 application at a concentration of 5 µmol/L. They were incubated for 72 h and then assessed for further studies. Western blot analyses were employed to examine the expression of inducible nitric oxide synthase (iNOS); Real-time PCR and ELISA were used to detect the mRNA expression and secretion of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß) and insulin-like growth factor-1 (IGF-1). RESULTS: In the hippocampal neuron-microglia co-cultures, Aß1-42 induced upregulation of iNOS, TNF-α and IL-1ß, downregulation of IGF-1. TGF-ß1 pretreatment ameliorated the pro-inflammatory effects caused by Aß1-42. CONCLUSIONS: TGF-ß1 significantly inhibits the increase in inflammatory cytokines and the decrease in neurotrophic factor which are caused by Aß1-42-induced microglia activation.

TGF-ß1 protection against Aß1-42-induced hippocampal neuronal inflammation and apoptosis by TßR-I.

Alzheimer's disease (AD), the most common chronic neurodegenerative disease, is pathologically characterized by the formation of neurofibrillary tangles because of hyperphosphorylation of tau protein and extracellular deposits of amyloid-ß (Aß) protein termed senile plaques. Recent studies indicate that neuronal apoptosis caused by chronic neuroinflammation is one of the important pathogenesis of AD. Transforming growth factor (TGF)-ß1 is a pleiotropic cytokine with immunosuppressive and anti-inflammatory properties. However, it is poorly known whether the anti-inflammatory property of TGF-ß1 is involved in a neuroprotection in AD. Here, an AD cell model of hippocampal neurons induced by Aß1-42 was used to show an anti-inflammatory and neuroprotective effect of TGF-ß1 through its receptor transforming growth factor-ß receptor type I (TßR-I). As expected, Aß1-42-induced an upregulation in neuronal expression of amyloid precursor protein (APP), tumor necrosis factor-α, cyclooxygenase-2, Bax, cleaved caspase-3, and cleaved caspase-9, and a downregulation in the expression of Bcl-2, as well as an increase in the number of NeuN/terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling (TUNEL) double-positive cells. TGF-ß1 pretreatment reduced the Aß1-42-induced effects of upregulating APP, tumor necrosis factor-α, Bax, cleaved caspase-3 and cleaved caspase-9, and downregulating Bcl-2, in addition to increasing NeuNTUNEL cell number. TßR-I expression in hippocampal neurons was downregulated by Aß1-42 exposure, but upregulated by TGF-ß1 pretreatment. Silencing of the TßR-I gene in the neurons abolished the anti-inflammatory and antiapoptotic effects of TGF-ß1 in the Aß1-42-induced AD cell model. These findings suggest that TGF-ß1 protects neurons against Aß1-42-induced neuronal inflammation and apoptosis by activation of TßR-I.

Interleukin-10 inhibits neuroinflammation-mediated apoptosis of ventral mesencephalic neurons via JAK-STAT3 pathway.

Neuroinflammation plays an important role in the pathogenesis of Parkinson's disease. Interleukin (IL)-10 is one of the most important and best anti-inflammatory cytokines. The objective of this report is to investigate whether IL-10 has any role in protecting ventral mesencephalic (VM) neurons in in vitro model of neuroinflammation. In this study, primary neuron-enriched culture was prepared from the VM tissues of E14 embryos of rats. The cells were pretreated with IL-10 (15 or 50ng/mL) for 1h followed by lipopolysaccharide (LPS, 50ng/mL) application. We found LPS induced neuronal apoptosis and loss while pretreatment with IL-10 reduced neuronal damage after exposure of LPS toxicity. Furthermore, signal transduction pathways related to IL-10 in VM neurons were studied in inflammatory condition. We used both shRNA and pharmacologic inhibition to determine the role of the IL-10 receptor (IL-10R) and its downstream signaling pathways in LPS-induced VM neuronal toxicity. Silence of the IL-10R gene in VM neurons abolished IL-10 mediated protection and the properties of anti-inflammatory and anti-apoptosis. IL-10 also induced phosphorylation of signal transducer and activator of transcription (STAT) 3 in VM neurons. Pretreatment with the specific Janus kinase (JAK) inhibitor reduced STAT3 phosphorylation and blocked IL-10 mediated protection against LPS. These findings suggest that IL-10 provides neuroprotection by acting via IL-10R and its down-stream JAK-STAT3 signal pathways in VM neurons.