21 research outputs found
Clinical characteristics and prognostic factors for short-term outcomes of autoimmune glial fibrillary acidic protein astrocytopathy: a retrospective analysis of 33 patients
BackgroundAutoimmune glial fibrillary acidic protein astrocytopathy (GFAP-A) is a recently discovered inflammatory central nervous system (CNS) disease, whose clinical characteristics and prognostic factors for short-term outcomes have not been defined yet. We aimed to assess the symptoms, laboratory tests, imaging findings, treatment, and short-term prognosis of GFAP-A.MethodsA double-center retrospective cohort study was performed between May 2018 and July 2022. The clinical characteristics and prognostic factors for short-term outcomes were determined.ResultsWe enrolled 33 patients with a median age of 28 years (range: 2–68 years), 15 of whom were children (<18 years). The clinical spectrum is dominated by meningoencephalomyelitis. Besides, we also found nausea, vomiting, poor appetite, and neuropathic pain in some GFAP-A patients, which were not mentioned in previous reports. And adults were more prone to limb numbness than children. Magnetic resonance imaging revealed lesions involving the brain parenchyma, meninges, and spinal cord, exhibiting patchy, linear, punctate, and strip T2 hyperintensities. First-line immunotherapy, including corticosteroid and gamma globulin, was effective in most patients in the acute phase (P = 0.02). However, patients with overlapping AQP4 antibodies did not respond well to first-line immunotherapy and coexisting neural autoantibodies were more common in women. Additionally, the short-term prognosis was significantly better in children than in adults (P = 0.04). Positive non-neural autoantibodies and proven viral infection were independent factors associated with poor outcomes (P = 0.03, 0.02, respectively).ConclusionWe expanded the spectrum of clinical symptoms of autoimmune GFAP-A. The clinical symptoms and short-term prognosis differed between children and adults. Positive non-neural autoantibodies and proven viral infection at admission suggest a poor short-term prognosis
β-Arrestin 2 Promotes Hepatocyte Apoptosis by Inhibiting AKT Protein
Recent studies reveal that multifunctional protein β-arrestin 2 (Arrb2) modulates cell apoptosis. Survival and various aspects of liver injury were investigated in WT and Arrb2KO mice after bile duct ligation (BDL). We found that deficiency of Arrb2 enhances survival and attenuates hepatic injury and fibrosis. Following BDL, Arrb2-deficient mice as compared with WT controls displayed a significant reduction of hepatocyte apoptosis as demonstrated by the TUNEL assay. Following BDL, the levels of phospho-Akt and phospho-glycogen synthase kinase 3β (GSK3β) in the livers were significantly increased in Arrb2 KO compared with WT mice, although p-p38 increased in WT but not in Arrb2-deficient mice. Inhibition of GSK3β following BDL decreases hepatic apoptosis and decreased p-p38 in WT mice but not in Arrb2 KO mice. Activation of Fas receptor with Jo2 reduces phospho-Akt and increases apoptosis in WT cells and WT mice but not in Arrb2-deficient cells and Arrb2-deficient mice. Consistent with direct interaction of Arrb2 with and regulating Akt phosphorylation, the expression of a full-length or N terminus but not the C terminus of Arrb2 reduces Akt phosphorylation and coimmunoprecipates with Akt. These results reveal that the protective effect of deficiency of Arrb2 is due to loss of negative regulation of Akt due to BDL and decreased downstream GSK3β and p38 MAPK signaling pathways
Ectopic expression of Miro 1 ameliorates seizure and inhibits hippocampal neurodegeneration in a mouse pilocarpine epilepsy model
Epilepsy is a common disease of the central nervous system. This study aims to investigate the role of mitochondrial Rho (Miro) 1 in epilepsy using a mouse model of pilocarpine-induced status epilepticus (SE). Intraperitoneal injection of pilocarpine induced epileptic seizure in mice and significantly decreased Miro 1 expression in the hippocampus. Moreover, pilocarpine treatment increased the serum levels of heat shock protein 70 (HSP70) and S100 calcium binding protein B (S100B), and led to hippocampal neuronal injury and apoptosis. The intrinsic apoptotic pathway was activated in the hippocampal neurons following pilocarpine-induced SE, as evidenced by increased levels of cleaved caspase-3 and Bax, downregulation of Bcl-2, and the release of cytochrome C from mitochondria to cytoplasm. By contrast, forced expression of Miro 1 by lateral ventricular administration of adenovirus mitigated pilocarpine-induced epileptic seizure, reduced the elevation of HSP70 and S100B, and inhibited hippocampal neuronal apoptosis by suppressing the intrinsic apoptotic pathway. In summary, our data demonstrated that ectopic expression of Miro 1 alleviated pilocarpine-induced SE and protected hippocampal neurons by inhibiting the intrinsic apoptotic pathway. These findings provide new insights in epileptic disorders and suggest a potential neuroprotective value of Miro 1 in the treatment of epilepsy.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author
Single-dose botulinum toxin type a compared with repeated-dose for treatment of trigeminal neuralgia: a pilot study
Abstract Background Several RCT studies including ours, seem to prove the role of Botulinum toxin type A (BTX-A) in the treatment of trigeminal neuralgia (TN), but no standardized dosing regimen has been established. In our study, we compare two different methods of administration: single-dose or repeated-dose strategy which was most frequently applied over the years in our centre. Methods An open-label trail was conducted. One hundred patients with classic TN symptoms were recruited, and randomly and equally apportioned to single- or repeated-dose group. Patients in the single-dose group received a local BTX-A injection of 70 to 100Â U. The repeated-dose group received an initial BTX-A injection of 50 to 70Â U and then another of equal volume 2Â weeks later. All patients were followed for 6Â months. Results In the single- and repeated-dose groups, 44 and 37, respectively, completed the entire study. The groups were statistically similar in TN frequency, time between treatment and effect, time to peak effect, VAS scores, and rates of adverse reactions (latency and duration). However, the single-dose group experienced significantly longer duration of effect (PÂ =Â 0.032). Conclusions The single- and repeated-dosing BTX-A regimens were largely comparable in efficacy and safety. This study suggests that repeated dosing has no advantage over single dosing of BTX-A for TN. Dosing should be adjusted for the individual patient
Single internal carotid cavernous sinus aneurysm presented as bilateral painful ophthalmoplegia: a case report
Abstract Background Intracranial aneurysms are the most common vascular cause of painful ophthalmoplegia. Symptoms include retro-orbital pain, diplopia, ophthalmoplegia, trigeminal neuropathy, or a combination of these. Most single aneurysms cause ipsilateral, painful ophthalmoplegia. Here, we report the first, to our knowledge, case of bilateral painful ophthalmoplegia possibly caused by an aneurysm of the cavernous segment of the left internal carotid artery. Case presentation A 62-year-old male patient presented with headache and bilateral ptosis. Laboratory tests revealed hypopituitary function. Computerized tomography angiography showed a large aneurysm in the cavernous sinus segment of the left internal carotid artery. Aneurysm embolization was performed in the Nerve Interventional Department. Four months after surgery, the patient's symptoms returned to normal. Conclusions This case suggests that patients with bilateral painful ophthalmoplegia should be screened for aneurysms using computed tomography angiography or magnetic resonance angiography immediately
β-Arrestin 2-Mediated Immune Suppression Induced by Chronic Stress
Objective: Stress, either physical or psychological, can modulate immune function. However, the mechanisms associated with stress-induced immune suppression remain to be elucidated. β-Arrestin 2 serves as adaptor, scaffold, and/or signal transducer. The role of β-arrestin 2 in stress-induced immune suppression is not known yet. Methods/Results: Here, we demonstrate that β-arrestin 2 deficiency in mice increases the sensitivity to the chronic stress-induced reduction in the number of splenocytes. Interestingly, the stress-induced suppression of T helper-type (Th) 1 cytokines and the increased production of Th2 cytokines were greatly enhanced in β-arrestin 2-deficient mice compared with wild-type mice. Moreover, inhibition of PI3K in β-arrestin 2-deficient mice exerts an additive effect on the stress-induced reduction in the number of splenocytes. Conclusion: Our study demonstrates that a deficiency in β-arrestin 2 augments stress-induced immune suppression
The Role of p38 MAPK in Valproic Acid Induced Microglia Apoptosis
Valproic acid (VPA), a widely prescribed drug for seizures and bipolar disorder, induces apoptosis in microglia, but the underlying mechanism by which microglia apoptosis in response to VPA is not yet known. In this study, we found that the mitochondrial pathway played an important role in VPA-induced apoptosis in both BV-2 microglia and mouse primary microglial cells. In addition, VPA increased the level of phospho-p38 mitogen-activated protein kinase (MAPK), but had no effects on phospho-ERK and phospho-JNK MAPKs. Moreover, p38 inhibitor SB203580 strongly inhibited VPA-induced apoptosis and caspase-3 activation. Taken together, our results clearly demonstrated that VPA could induce apoptosis of microglia via p38 MAPK and mitochondrial apoptosis pathway
Curcumin Improves Amyloid β-Peptide (1-42) Induced Spatial Memory Deficits through BDNF-ERK Signaling Pathway
<div><p>Curcumin, the most active component of turmeric, has various beneficial properties, such as antioxidant, anti-inflammatory, and antitumor effects. Previous studies have suggested that curcumin reduces the levels of amyloid and oxidized proteins and prevents memory deficits and thus is beneficial to patients with Alzheimer’s disease (AD). However, the molecular mechanisms underlying curcumin’s effect on cognitive functions are not well-understood. In the present study, we examined the working memory and spatial reference memory in rats that received a ventricular injection of amyloid-β1-42 (Aβ1-42), representing a rodent model of Alzheimer’s disease (AD). The rats treated with Aβ1-42 exhibited obvious cognitive deficits in behavioral tasks. Chronic (seven consecutive days, once per day) but not acute (once a day) curcumin treatments (50, 100, and 200 mg/kg) improved the cognitive functions in a dose-dependent manner. In addition, the beneficial effect of curcumin is accompanied by increased BDNF levels and elevated levels of phosphorylated ERK in the hippocampus. Furthermore, the cognition enhancement effect of curcumin could be mimicked by the overexpression of BDNF in the hippocampus and blocked by either bilateral hippocampal injections with lentiviruses that express BDNF shRNA or a microinjection of ERK inhibitor. These findings suggest that chronic curcumin ameliorates AD-related cognitive deficits and that upregulated BDNF-ERK signaling in the hippocampus may underlie the cognitive improvement produced by curcumin.</p></div
Functional traits composition predict macrophytes community productivity along a water depth gradient in a freshwater lake
Functional trait composition of plant communities has been proposed as a helpful key for understanding the mechanisms of biodiversity effects on ecosystem functioning. In this study, we applied a step-wise modeling procedure to test the relative effects of taxonomic diversity, functional identity, and functional diversity on macrophytes community productivity along water depth gradient. We sampled 42 plots and 1513 individual plants and measured 16 functional traits and abundance of 17 macrophyte species. Results showed that there was a significant decrease in taxonomic diversity, functional identity (i.e., stem dry mass content, leaf [C] and leaf [N]), and functional diversity (i.e., floating leaf, mean Julian flowering date and rooting depth) with increasing water depth. For the multiple-trait functional diversity (FD) indices, functional richness decreased, while functional divergence increased with water depth gradient. Macrophyte community productivity was strongly determined by functional trait composition within community, but not significantly affected by taxonomic diversity. Community-weighted means (CWM) showed a two times higher explanatory power relative to FD indices in determining variations in community productivity. For nine of sixteen traits, CWM and FD showed significant correlations with community productivity, although the strength and direction of those relations depended on selected trait. Furthermore, functional composition in a community affected productivity through either additive or opposite effects of CWM and FD, depending on the particular traits being considered. Our results suggested both mechanisms of mass ratio and niche complementarity can operate simultaneously on variations in community productivity, and considering both CWM and FD would lead to a more profound understanding of traits-productivity relationships.Functional trait composition of plant communities has been proposed as a helpful key for understanding the mechanisms of biodiversity effects on ecosystem functioning. In this study, we applied a step-wise modeling procedure to test the relative effects of taxonomic diversity, functional identity, and functional diversity on macrophytes community productivity along water depth gradient. We sampled 42 plots and 1513 individual plants and measured 16 functional traits and abundance of 17 macrophyte species. Results showed that there was a significant decrease in taxonomic diversity, functional identity (i.e., stem dry mass content, leaf [C] and leaf [N]), and functional diversity (i.e., floating leaf, mean Julian flowering date and rooting depth) with increasing water depth. For the multiple-trait functional diversity (FD) indices, functional richness decreased, while functional divergence increased with water depth gradient. Macrophyte community productivity was strongly determined by functional trait composition within community, but not significantly affected by taxonomic diversity. Community-weighted means (CWM) showed a two times higher explanatory power relative to FD indices in determining variations in community productivity. For nine of sixteen traits, CWM and FD showed significant correlations with community productivity, although the strength and direction of those relations depended on selected trait. Furthermore, functional composition in a community affected productivity through either additive or opposite effects of CWM and FD, depending on the particular traits being considered. Our results suggested both mechanisms of mass ratio and niche complementarity can operate simultaneously on variations in community productivity, and considering both CWM and FD would lead to a more profound understanding of traits-productivity relationships