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.

Effect of cisplatin on the clock genes expression in the liver, heart and kidney.

Cisplatin is a platinum-based chemotherapy drug that is widely used to treat various types of malignancies. Although the involvement of circadian clock in cisplatin metabolism and excretion has been reported, the effect of cisplatin on circadian rhythm remains unclear. In the present study, we investigated the effects of cisplatin on clock genes expression in mouse peripheral tissues. Cisplatin induced severe nephrotoxicity, as revealed by the significant increase of blood urea nitrogen and serum creatinine levels. Moreover, cisplatin circadian time-dependently induced p21 expression in the liver, heart and kidney, with the highest increase during the dark phase. In addition, cisplatin altered the clock genes expression in the liver, heart and kidney in a tissue- and gene-specific manner. Interesting, the expression of D site of the albumin promoter binding protein (Dbp), a gene involved in detoxification and drug metabolism, was consistently suppressed in the liver, heart and kidney after cisplatin treatment, implying a role of DBP in the toxicity of cisplatin.

Treg Cells Protect Dopaminergic Neurons against MPP+ Neurotoxicity via CD47-SIRPA Interaction.

BACKGROUND/AIMS: Regulatory T (Treg) cells have been associated with neuroprotection by inhibiting microglial activation in animal models of Parkinson's disease (PD), a progressive neurodegenerative disease characterized by dopaminergic neuronal loss in the nigrostriatal system. Herein, we show that Treg cells directly protect dopaminergic neurons against 1-methyl-4-phenylpyridinium (MPP+) neurotoxicity via an interaction between the two transmembrane proteins CD47 and signal regulatory protein α (SIRPA). METHODS: Primary ventral mesencephalic (VM) cells or VM neurons were pretreated with Treg cells before MPP+ treatment. Transwell co-culture of Treg cells and VM neurons was used to assess the effects of the Treg cytokines transforming growth factor (TGF)-ß1 and interleukin (IL)-10 on dopaminergic neurons. Live cell imaging system detected a dynamic contact of Treg cells with VM neurons that were stained with CD47 and SIRPA, respectively. Dopaminergic neuronal loss, which was assessed by the number of tyrosine hydroxylase (TH)-immunoreactive cells, was examined after silencing CD47 in Treg cells or silencing SIRPA in VM neurons. RESULTS: Treg cells prevented MPP+-induced dopaminergic neuronal loss and glial inflammatory responses. TGF-ß1 and IL-10 secreted from Treg cells did not significantly prevent MPP+-induced dopaminergic neuronal loss in transwell co-culture of Treg cells and VM neurons. CD47 and SIRPA were expressed by Treg cells and VM neurons, respectively. CD47-labeled Treg cells dynamically contacted with SIRPA-labeled VM neurons. Silencing CD47 gene in Treg cells impaired the ability of Treg cells to protect dopaminergic neurons against MPP+ toxicity. Similarly, SIRPA knockdown in VM neurons reduced the ability of Treg cell neuroprotection. Rac1/Akt signaling pathway in VM neurons was activated by CD47-SIRPA interaction between Treg cells and the neurons. Inhibiting Rac1/Akt signaling in VM neurons compromised Treg cell neuroprotection. CONCLUSION: Treg cells protect dopaminergic neurons against MPP+ neurotoxicity by a cell-to-cell contact mechanism underlying CD47-SIRPA interaction and Rac1/Akt activation.

Cerebellar ataxia induced by 3-AP affects immunological function.

OBJECTIVE: We previously showed that the cerebellum modulates the immune system. Here we determined whether cerebellar ataxia alters immunological function to further demonstrate an involvement of the cerebellum in immune modulation. METHODS: Neurotoxin 3-acetylpyridine (3-AP) was intraperitoneally injected in rats to induce cerebellar ataxia. Behavior and motor coordination were tested on day 7 following 3-AP injection. Nissl staining and high-performance liquid chromatography (HPLC) were used to determine neuronal loss and neurotransmitter contents, respectively, in all the three cerebellar nuclei, fastigial nucleus (FN), interposed nucleus (IN) and dentate nucleus (DN). T and B lymphocyte differentiation and function were measured by flow cytometry, Western blot and ELISA. RESULTS: 3-AP induced motor discoordination and locomotor reduction. In all the three cerebellar nuclei, FN, IN and DN, there was a neuronal loss and a decrease in contents of glutamate and GABA (but not glycine) after 3-AP injection. Importantly, CD4+ T cells, but not CD8+ T cells, were increased by the 3-AP treatment. Moreover, interferon (IFN)-γ-producing cells and interleukin (IL)-17-producing cells were decreased in cerebellar ataxia rats, but IL-4-producing cells and CD25-expressing cells were increased. Expression of the T helper (Th)1- and Th17-related cytokines, IFN-γ, IL-2, IL-17 and IL-22, was downregulated in CD4+ cells in cerebellar ataxia rats, while expression of the Th2 and regulatory T (Treg)-related cytokines, IL-4, IL-5, IL-10 and transforming growth factor (TGF)-ß, was upregulated. Furthermore, B lymphocyte number and anti-bovine serum albumin (BSA) IgM and IgG antibody levels were elevated in cerebellar ataxia. CONCLUSION: Cerebellar ataxia alters cellular and humoral immunity.

Cerebellar fastigial nuclear GABAergic projections to the hypothalamus modulate immune function.

Our previous work has shown that the cerebellar fastigial nucleus (FN) is involved in modulation of lymphocyte function. Herein, we investigated effect of FN γ-aminobutyric acid (GABA)-ergic projections to the hypothalamus on lymphocytes to understand pathways and mechanisms underlying cerebellar immunomodulation. By injection of Texas red dextran amine (TRDA), an anterograde tracer, into FN, we found that the TRDA-labeled fibers from the FN traveled through the superior cerebellar peduncle (SCP), crossed in decussation of SCP (XSCP), entered the hypothalamus, and primarily terminated in the lateral hypothalamic area (LHA). Further, by injecting Fluoro-Ruby (FR), a retrograde tracer, in LHA, we observed that the FR-stained fibers retrogradely passed through XSCP and reached FN. Among these FR-positive neurons in the FN, there were GABA-immunoreactive cells. We then microinjected vigabatrin, which is an inhibitor of GABA-transaminase (GABA-T) that degrades GABA, bilaterally into FN. The vigabatrin treatment increased both number of GABA-immunoreactive neurons in FN-LHA projections and GABA content in the hypothalamus. Simultaneously, vigabatrin significantly reduced concanavalin A (Con A)-induced lymphocyte proliferation, anti-sheep red blood cell (SRBC) IgM antibody level, and natural killer (NK) cell number and cytotoxicity. In support of these findings, we inhibited GABA synthesis by using 3-mercaptopropionic acid (3-MP), which antagonizes glutamic acid decarboxylase (GAD). We found that the inhibition of GABA synthesis caused changes that were opposite to those when GABA was increased with vigabatrin. These findings show that the cerebellar FN has a direct GABAergic projection to the hypothalamus and that this projection actively participates in modulation of lymphocytes.

Effect of Cerebellohypothalamic Glutamatergic Projections on Immune Function.

Our previous work has shown that lesions of the cerebellar interposed nuclei (IN) suppress immune cell functions. Since there is no direct structural connection between the cerebellum and immune system, we explored the pathway mediating the cerebellar immunomodulation at the profile of cerebellohypothalamic projections to understand this modulation. Anterograde tracing of nerve tracts from the cerebellar IN to the hypothalamus was conducted by injection of anterograde tracer dextran-texas red (dextran-TR) in the cerebellar IN. We observed that dextran-TR-labeled nerve fibers, which were sent by cerebellar IN neurons, traveled in the superior cerebellar peduncle (SCP), crossed in SCP decussation, and entered the hypothalamus. In the hypothalamus, the fibers mostly terminated in the lateral hypothalamic area (LHA). Retrograde tracing by injection of retrograde tracer fluoro-ruby (FR) in the LHA found that FR-labeled neurons appeared in contralateral cerebellar IN. Fluorescent immunohistochemistry for glutamate revealed that many of the FR-labeled neurons were glutamatergic. These results demonstrate a direct glutamatergic projection from the cerebellar IN to the LHA. Reduction of the cerebellohypothalamic glutamatergic projections by microinjection of 6-diazo-5-oxo- L-norleucine (DON), an inhibitor of glutaminase for glutamate synthesis, in bilateral cerebellar IN led to suppression of peripheral lymphocyte number, T lymphocyte proliferation, and serum anti-sheep red blood cell IgM level. But the DON injection in the cerebellar cortex that does not send axons to the hypothalamus did not significantly alter all the immune parameters. These findings suggest that cerebellohypothalamic glutamatergic projection modulates immune function, and that via the pathway, the cerebellum implements its immunoregulatory effect.

The hypothalamus mediates the effect of cerebellar fastigial nuclear glutamatergic neurons on humoral immunity.

OBJECTIVES: We explored effect of glutamatergic neurons in the fastigial nucleus (FN), one of three cerebellar nuclei, on humoral immunity and revealed that this effect was mediated by the hypothalamus via FN-hypothalamic glutamatergic transmission. METHODS: Rats were immunized with bovine serum albumin (BSA). On the third day after the immunization, 6-diazo-5-oxo-L-norleucine (DON), an inhibitor of glutaminase for glutamate synthesis, was microinjected in bilateral FN and D,L-threo-ß-hydroxyaspartic acid (THA), an inhibitor of glutamate transporters on plasma membrane, was microinjected in both sides of lateral hypothalamic area (LHA). Glutamate content in the hypothalamus was examined by high-performance liquid chromatography (HPLC). Flow cytometry and enzyme-linked immunosorbent assay (ELISA) were used to measure B lymphocyte percentage in mononuclear cells of peripheral blood and levels of anti-BSA IgM and IgG antibodies in the serum, respectively. RESULTS: DON injection in bilateral FN reduced B lymphocyte percentage and anti-BSA IgM and IgG levels, and simultaneously decreased glutamate content in the hypothalamus. Combined treatment with DON in the FN and with THA in the LHA elevated B cell number and anti-BSA IgM and IgG levels and increased hypothalamic glutamate content compared with DON treatment alone. However, combined treatment with DON in the FN and with THA in the ventrolateral thalamic nuclei (VL) did not significantly alter DON-dependent changes in B cell number and antibody levels, although the co-treatment altered DON-dependent glutamate content in the thalamus. CONCLUSION: Cerebellar FN glutamatergic neurons participate in modulation of humoral immunity and this effect is mediated by the hypothalamus via FN-hypothalamic glutamatergic transmission.

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.

Role of cerebellohypothalamic GABAergic projection in mediating cerebellar immunomodulation.

Our previous studies have shown that the cerebellar interposed nucleus (IN) modulates lymphocyte functions. As the cerebellum does not have a direct contact with the immune system, it is required to explore the pathway mediating the cerebellar immunomodulation. In this study, both lymphocyte percentage in peripheral leukocytes and lymphocyte proliferation induced by concanavalin A were reduced by the bilateral IN lesions with kainic acid. Anterograde tracing of nerve tracts with biotinylated dextran amine (BDA) from the cerebellum to the hypothalamus revealed that the BDA-labeled fibers from the cerebellar IN neurons traveled through superior cerebellar peduncle (SCP), crossed in SCP decussation, and primarily terminated in lateral hypothalamic area (LHA). Retrograde tracing with wheat germ agglutinin-horseradish peroxidase from the LHA to the cerebellar IN combined with immunohistochemistry for gamma-aminobutyric acid (GABA) or glutamate in the cerebellar sections displayed that the neuronal projections from the cerebellar IN to the LHA mostly were GABAergic. Blockage of GABA(A) receptors in the LHA with hydrastine led to a reduction in the lymphocyte percentage and proliferation, similar to the IN lesions. These results show a direct GABAergic projection from cerebellar IN to LHA and suggest that the projection mediates cerebellar immunomodulation.

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.

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.

Triptolide interrupts rRNA synthesis and induces the RPL23­MDM2­p53 pathway to repress lung cancer cells.

Lung cancer has one of the highest mortalities of any cancer worldwide. Triptolide (TP) is a promising tumor suppressor extracted from the Chinese herb Tripterygium wilfordii. Our previous proteomics analysis revealed that TP significantly interfered with the ribosome biogenesis pathway; however, the underlying molecular mechanism remains poorly understood. The aim of the present study was to determine the molecular mechanism of TP's anticancer effect by investigating the association between ribosomal stress and p53 activation. It was found that TP induces nucleolar disintegration together with RNA polymerase I (Pol I) and upstream binding factor (UBF) translocation. TP interrupted ribosomal (r)RNA synthesis through inhibition of RNA Pol I and UBF transcriptional activation. TP treatment increased the binding of ribosomal protein L23 (RPL23) to mouse double minute 2 protein (MDM2), resulting in p53 being released from MDM2 and stabilized. Activation of p53 induced apoptosis and cell cycle arrest by enhancing the activation of p53 upregulated modulator of apoptosis, caspase 9 and caspase 3, and suppressing BCL2. In vivo experiments showed that TP significantly reduced xenograft tumor size and increased mouse body weight. Immunohistochemical assays confirmed that TP significantly increased the p53 level and induced nucleolus disintegration, during which nucleolin distribution moved from the nucleolus to the nucleoplasm, and RPL23 clustered at the edge of the cell membrane. Therefore, it was proposed that TP induces ribosomal stress, which leads to nucleolus disintegration, and inhibition of rRNA transcription and synthesis, resulting in increased binding of RPL23 with MDM2. Consequently, p53 is activated, which induces apoptosis and cell cycle arrest.

Neuroprotection of interleukin-6 against NMDA attack and its signal transduction by JAK and MAPK.

Cytokine interleukin-6 (IL-6) has been well shown to be elevated in brain injury and diseases. However, the significance of IL-6 production in such neuropathologic states remains controversial, and the intracellular signal-transduction pathways involved in the brain IL-6 action are primarily unclear. We previously indicated that exogenous IL-6 protected neurons against glutamate and N-methyl-d-aspartate (NMDA) attacks and the effects of IL-6 was blocked by anti-gp130 antibody. Here, we provide further evidence for the IL-6 neuroprotection and show signal molecules transducing the IL-6 message. The cerebellar granule neurons from postnatal 8-day infant rats were exposed to IL-6 for 8 days, and also pretreated chronically with Janus kinase (JAK) inhibitor AG490 and mitogen-activated protein kinase (MAPK) inhibitor PD98059. NMDA stimulated the cultured neurons for 30 min to induce neuronal injury and death. Cell counting kit-8 assay and Western blot were employed to measure neuronal vitality and cleaved caspase-3 expression, respectively. The chronic IL-6 exposure prevented the suppression of the neuronal vitality and the enhancement of the cleaved caspase-3 level induced by NMDA. The neuroprotective effect of IL-6 depended on IL-6 concentration and neuronal damaged degree. IL-6-induced STAT3 phosphorylation was inhibited by AG490 but not by PD98059; and IL-6-induced ERK1/2 activation was blocked by PD98059 but not by AG490. Either AG490 or PD98059 blocked the IL-6 protection against the NMDA-elicited neuronal vitality decrease and caspase-3 activation increase. These findings suggest that IL-6 protects neurons from NMDA-induced excitoxicity and the IL-6 neuroprotection may be transduced by both JAK/STAT3 and RAS/MAPK pathways.

RNF216 Regulates the Migration of Immortalized GnRH Neurons by Suppressing Beclin1-Mediated Autophagy.

RNF216, encoding an E3 ubiquitin ligase, has been identified as a causative gene for Gordon Holmes syndrome, characterized by ataxia, dementia, and hypogonadotropic hypogonadism. However, it is still elusive how deficiency in RNF216 leads to hypogonadotropic hypogonadism. In this study, by using GN11 immature GnRH neuronal cell line, we demonstrated an important role of RNF216 in the GnRH neuron migration. RNA interference of RNF216 inhibited GN11 cell migration, but had no effect on the proliferation of GN11 cells or GnRH expression. Knockdown of RNF216 increased the protein levels of its targets, Arc and Beclin1. RNAi of Beclin1, but not Arc, normalized the suppressive effect caused by RNF216 knockdown. As Beclin1 plays a critical role in the autophagy regulation, we further demonstrated that RNAi of RNF216 led to increase in autophagy, and autophagy inhibitor CQ and 3-MA rescued the GN11 cell migration deficit caused by RNF216 knockdown. We further demonstrated that pharmacological increase autophagy by rapamycin could suppress the GN11 cell migration. We thus have identified that RNF216 regulates the migration of GnRH neuron by suppressing Beclin1 mediated autophagy, and indicated a potential contribution of autophagy to the hypogonadotropic hypogonadism.

Th17 Cells Induce Dopaminergic Neuronal Death via LFA-1/ICAM-1 Interaction in a Mouse Model of Parkinson's Disease.

T helper (Th)17 cells, a subset of CD4+ T lymphocytes, have strong pro-inflammatory property and appear to be essential in the pathogenesis of many inflammatory diseases. However, the involvement of Th17 cells in Parkinson's disease (PD) that is characterized by a progressive degeneration of dopaminergic (DAergic) neurons in the nigrostriatal system is unclear. Here, we aimed to demonstrate that Th17 cells infiltrate into the brain parenchyma and induce neuroinflammation and DAergic neuronal death in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)- or 1-methyl-4-phenylpyridinium (MPP+)-induced PD models. Blood-brain barrier (BBB) disruption in the substantia nigra (SN) was assessed by the signal of FITC-labeled albumin that was injected into blood circulation via the ascending aorta. Live cell imaging system was used to observe a direct contact of Th17 cells with neurons by staining these cells using the two adhesion molecules, leukocyte function-associated antigen (LFA)-1 and intercellular adhesion molecule (ICAM)-1, respectively. Th17 cells invaded into the SN where BBB was disrupted in MPTP-induced PD mice. Th17 cells exacerbated DAergic neuronal loss and pro-inflammatory/neurotrophic factor disorders in MPP+-treated ventral mesencephalic (VM) cell cultures. A direct contact of LFA-1-stained Th17 cells with ICAM-1-stained VM neurons was dynamically captured. Either blocking LFA-1 in Th17 cells or blocking ICAM-1 in VM neurons with neutralizing antibodies abolished Th17-induced DAergic neuronal death. These results establish that Th17 cells infiltrate into the brain parenchyma of PD mice through lesioned BBB and exert neurotoxic property by promoting glial activation and importantly by a direct damage to neurons depending on LFA-1/ICAM-1 interaction.

TGF-ß1 Neuroprotection via Inhibition of Microglial Activation in a Rat Model of Parkinson's Disease.

Transforming growth factor (TGF)-ß1 is a pleiotropic cytokine with immunosuppressive and anti-inflammatory properties. Recently we have shown that TGF-ß1 pretreatment in vitro protects against 1-methyl-4-phenylpyridinium (MPP+)-induced dopaminergic neuronal loss that characterizes in Parkinson's disease (PD). Herein, we aimed to demonstrate that TGF-ß1 administration in vivo after MPP+ toxicity has neuroprotection that is achieved by a mediation of microglia. A rat model of PD was prepared by injecting MPP+ unilaterally in the striatum. At 14 days after MPP+ injection, TGF-ß1 was administrated in the right lateral cerebral ventricle. Primary ventral mesencephalic (VM) neurons and cerebral cortical microglia were treated by MPP+, respectively, and TGF-ß1 was applied to neuronal or microglial cultures at 1 h after MPP+ treatment. As expected, MPP+ resulted in decrease in TGF-ß1 production in the substantia nigra and in primary VM neurons and microglia. TGF-ß1 intracerebroventricular administration alleviated MPP+-induced PD-like changes in pathology, motor coordination and behavior. Meanwhile, TGF-ß1 ameliorated MPP+-induced microglial activation and inflammatory cytokine production in vivo. Interestingly, TGF-ß1 treatment was not able to ameliorate MPP+-induced dopaminergic neuronal loss and caspase-3/9 activation in mono-neuron cultures, but TGF-ß1 alleviated MPP+-induced microglial activation and inflammatory cytokine production in microglia-enriched cultures. This effect of TGF-ß1 inhibiting microglial inflammatory response was blocked by Smad3 inhibitor SIS3. Importantly, neuronal exposure to supernatants of primary microglia that had been treated with TGF-ß1 reduced dopaminergic neuronal loss and caspase-3/9 activation induced by MPP+-treated microglial supernatants. These findings establish that TGF-ß1 exerts neuroprotective property in PD by inhibiting microglial inflammatory response via Smad3 signaling.

Cerebellar fastigial nuclear glutamatergic neurons regulate immune function via hypothalamic and sympathetic pathways.

We previously have shown that cerebellar fastigial nucleus (FN) modulates immune function, but pathways or mechanisms underlying this immunomodulation require clarification. Herein, an anterograde and retrograde tracing of nerve tracts between the cerebellar FN and hypothalamus/thalamus was performed in rats. After demonstrating a direct cerebellar FN-hypothalamic/thalamic glutamatergic projection, 6-diazo-5-oxo-L-norleucine (DON), an inhibitor of glutaminase that catalyzes glutamate synthesis, was injected bilaterally in the cerebellar FN and simultaneously, D,L-threo-ß-hydroxyaspartic acid (THA), an inhibitor of glutamate transporters on cell membrane, was bilaterally injected in the lateral hypothalamic area (LHA) or the ventrolateral (VL) thalamic nucleus. DON treatment in the FN alone decreased number of glutamatergic neurons that projected axons to the LHA and also diminished glutamate content in both the hypothalamus and the thalamus. These effects of DON were reduced by combined treatment with THA in the LHA or in the VL. Importantly, DON treatment in the FN alone attenuated percentage and cytotoxicity of natural killer (NK) cells and also lowered percentage and cytokine production of T lymphocytes. These DON-caused immune effects were reduced or abolished by combined treatment with THA in the LHA, but not in the VL. Simultaneously, DON treatment elevated level of norepinephrine (NE) in the spleen and mesenteric lymphoid nodes, and THA treatment in the LHA, rather than in the VL, antagonized the DON-caused NE elevation. These findings suggest that glutamatergic neurons in the cerebellar FN regulate innate and adaptive immune functions and the immunomodulation is conveyed by FN-hypothalamic glutamatergic projections and sympathetic nerves that innervate lymphoid tissues.

A novel mutation of GATA4 (K319E) is responsible for familial atrial septal defect and pulmonary valve stenosis.

Congenital heart disease (CHD) is the most common birth defect in humans, and the etiology of most CHD remains to be elusive. Atrial septal defect (ASD) makes up 30­40% of all adult CHDs and is thought to be genetically heterogeneous. Previous studies have demonstrated that mutations in transcription factors e.g. NKX2.5, GATA4, and TBX5 contribute to congenital ASD. In this study, we investigate a family of three generations with seven patients with ASD and pulmonary valve stenosis (PS). A novel GATA4 mutation, c.955ANG (p.K319E), was identified and co-segregated with the affected patients in this family. This mutation was predicted to be deleterious by three different bioinformatics programs (The polyphen2, SIFT and MutationTaster). Our finding expands the spectrum of GATA4 mutations and provides additional support that GATA4 plays important roles in cardiac development.

Dopamine receptors modulate cytotoxicity of natural killer cells via cAMP-PKA-CREB signaling pathway.

Dopamine (DA), a neurotransmitter in the nervous system, has been shown to modulate immune function. We have previously reported that five subtypes of DA receptors, including D1R, D2R, D3R, D4R and D5R, are expressed in T lymphocytes and they are involved in regulation of T cells. However, roles of these DA receptor subtypes and their coupled signal-transduction pathway in modulation of natural killer (NK) cells still remain to be clarified. The spleen of mice was harvested and NK cells were isolated and purified by negative selection using magnetic activated cell sorting. After NK cells were incubated with various drugs for 4 h, flow cytometry measured cytotoxicity of NK cells against YAC-1 lymphoma cells. NK cells expressed the five subtypes of DA receptors at mRNA and protein levels. Activation of D1-like receptors (including D1R and D5R) with agonist SKF38393 enhanced NK cell cytotoxicity, but activation of D2-like receptors (including D2R, D3R and D4R) with agonist quinpirole attenuated NK cells. Simultaneously, SKF38393 elevated D1R and D5R expression, cAMP content, and phosphorylated cAMP-response element-binding (CREB) level in NK cells, while quinpirole reduced D3R and D4R expression, cAMP content, and phosphorylated CREB level in NK cells. These effects of SKF38393 were blocked by SCH23390, an antagonist of D1-like receptors, and quinpirole effects were abolished by haloperidol, an antagonist of D2-like receptors. In support these results, H89, an inhibitor of phosphokinase A (PKA), prevented the SKF38393-dependent enhancement of NK cells and forskolin, an activator of adenylyl cyclase (AC), counteracted the quinpirole-dependent suppression of NK cells. These findings show that DA receptor subtypes are involved in modulation of NK cells and suggest that D1-like receptors facilitate NK cells by stimulating D1R/D5R-cAMP-PKA-CREB signaling pathway and D2-like receptors suppress NK cells by inhibiting D3R/D4R-cAMP-PKA-CREB signaling pathway. The results may provide more targets of therapeutic strategy for neuroimmune diseases.

[Depression and associated factors among migrant women of reproductive age in some areas of Wuhan].

OBJECTIVE: To understand factors as social support, situation of depression and related risk factors among migrant women of reproductive age in some areas of Wuhan. METHODS: Cluster sampling method and face-to-face interview with structured questionnaire were used to investigate 316 migrant women in Wuhan. RESULTS: The overall prevalence rate of depression was 32.3%. RESULTS: from binary logistic regression analysis showed that factors as: under pressure (OR = 4.010, 95%CI: 1.672 - 9.617), having had negative life events (OR = 2.050, 95%CI: 1.170 - 3.591) or tight relations with neighbors (OR = 2.537, 95%CI: 1.053 - 6.113), not quite satisfied (OR = 4.247, 95%CI: 1.521 - 11.855) or satisfied (OR = 2.411, 95%CI: 1.111 - 5.233), on his/her own health status etc., might serve as the possible risk factors for depression. In scores related to social support, and the utilization of such support, there were statistically significant differences seen between the groups with depression and the one without. CONCLUSION: The prevalence of depression among migrant women of reproductive age appeared to be high in some areas on Wuhan. Factors as: under pressure, having had negative life events, tight relations with neighbors, status on satisfaction of one's own health situation as well as related social support, seemed to be the main risk factors for depression in this population.