RESUMO
Autoimmune encephalitis is a rapidly progressive inflammatory brain disease. Gamma-aminobutyric acid type B (GABAB) receptor autoimmune encephalitis is a rare subtype characterized by distinct clinical features. Diagnosis can be especially challenging when typical limbic symptoms and neuroimaging findings are absent. This case report underscores the importance of identifying this condition and starting immunosuppressive treatment promptly. A 59-year-old man presented with gait disturbances, dysarthria, and severe ataxia without cognitive impairment. Initial examinations, including a brain MRI, were unremarkable, except for an elevated cell count and protein in the cerebrospinal fluid. Despite receiving initial empirical antiviral treatment, his symptoms worsened, prompting the administration of intravenous methylprednisolone and immunoglobulin. After these immunosuppressive therapies, the cerebellar symptoms showed gradual improvement. Subsequent testing for antibodies to the GABAB receptor was positive in both the serum and cerebrospinal fluid. Follow-up MRI revealed cerebellar atrophy, consistent with a diagnosis of GABAB receptor-associated acute cerebellitis. This case illustrates that cerebellar symptoms can occur in the absence of more common limbic manifestations in GABAB receptor autoimmune encephalitis. The progression of cerebellar atrophy following an initially normal MRI is a significant finding that offers supporting evidence for the diagnosis of cerebellitis. A review of the literature identified similar cases of acute cerebellitis without limbic symptoms, although neuroimaging abnormalities in the cerebellum were not reported. Our case underscores the importance of increased clinical awareness and consideration of autoimmune causes, even when neuroimaging appears normal. Early and appropriate immunosuppressive therapy may help change the course of the disease and enhance patient outcomes.
RESUMO
BACKGROUND: In Japan, only two medications of immediate-release levodopa with distinct ratios of decarboxylase inhibitor (DCI), namely levodopa/benserazide 100/25 mg and levodopa/carbidopa 100/10 mg, are available for the treatment of Parkinson's disease (PD). The relationship between the difference in the DCI to levodopa ratio and the development of motor complications in long-term administration of levodopa is unknown. PURPOSE: We assessed the duration from initiation of levodopa/DCI to the emergence of motor fluctuations in patients with PD treated with levodopa/benserazide and levodopa/carbidopa. METHODS: We retrospectively assessed the disease course, especially the period from the onset of motor symptoms or initiation of levodopa/DCI to the emergence of motor fluctuations, in patients with PD who were initially treated with either levodopa/benserazide (300/75 mg/day) or levodopa/carbidopa (300/30 mg/day). RESULTS: Of the 186 candidates, 52 patients were enrolled. The mean duration to the emergence of motor fluctuations in the levodopa/carbidopa group was significantly longer than that in the levodopa/benserazide group (5.0 ± 1.4 vs 3.1 ± 1.2 years, p < 0.01). The mean duration from onset of motor symptoms to the emergence of motor fluctuations in the levodopa/carbidopa group was also significantly longer than that in the levodopa/benserazide group (6.6 ± 1.6 vs 4.7 ± 1.3 years, p < 0.01). CONCLUSION: Our study suggests that levodopa/carbidopa therapy with a DCI to levodopa ratio of 1:10 may delay the occurrence of motor fluctuations when compared to levodopa/benserazide therapy with that of 1:4. The difference in the blending ratio of levodopa/DCI may influence the disease progression in PD.
Assuntos
Carbidopa , Doença de Parkinson , Antiparkinsonianos/efeitos adversos , Benserazida/efeitos adversos , Carbidopa/efeitos adversos , Combinação de Medicamentos , Humanos , Levodopa/efeitos adversos , Doença de Parkinson/complicações , Doença de Parkinson/tratamento farmacológico , Estudos RetrospectivosRESUMO
Human group-specific component protein (Gc protein) is a multifunctional serum protein which has three common allelic variants, Gc1F, Gc1S and Gc2 in humans. Gc1 contains an O-linked trisaccharide [sialic acid-galactose-N-acetylgalactosamine (GalNAc)] on the threonine420 (Thr420) residue and can be converted to a potent macrophage activating factor (GcMAF) by selective removal of sialic acid and galactose, leaving GalNAc at Thr420. In contrast, Gc2 is not glycosylated. GcMAF is considered a promising candidate for immunotherapy and antiangiogenic therapy of cancers and has attracted great interest, but it remains difficult to compare findings among research groups because different procedures have been used to prepare GcMAF. Here, we present a simple, practical method to prepare high-quality GcMAF by overexpressing Gc-protein in a serum-free suspension culture of ExpiCHO-S cells, without the need for a de-glycosylation step. We believe this protocol is suitable for large-scale production of GcMAF for functional analysis and clinical testing.
Assuntos
Fatores Ativadores de Macrófagos/síntese química , Proteína de Ligação a Vitamina D/síntese química , Animais , Células CHO , Proliferação de Células/efeitos dos fármacos , Cricetulus , Humanos , Fatores Ativadores de Macrófagos/farmacologia , Fagocitose/efeitos dos fármacos , Proteína de Ligação a Vitamina D/farmacologiaRESUMO
Taking good care of elderly is a major challenge of our society, and thus identification of potential drug targets to reduce age-associated disease burden is desirable. α-klotho(-/-) (α-kl) is a short-lived mouse model that displays multiple phenotypes resembling human aging-related syndromes. Such ageing phenotype of α-kl(-/-) mice is associated with activation of a proteolytic enzyme, Calpain-1. We hypothesized that uncontrolled activation of calpain-1 might be causing age-related phenotypes in α-kl-deficient mice. We found that daily administration of BDA-410, a calpain-1 inhibitor, strikingly ameliorated multiple aging-related phenotypes. Treated mice showed recovery of reproductive ability, increased body weight, reduced organ atrophy, and suppression of ectopic calcifications, bone mineral density reduction, pulmonary emphysema and senile atrophy of skin. We also observed ectopic expression of FGF23 in calcified arteries of α-kl(-/-) mice, which might account for the clinically observed association of increased FGF23 level with increased risk of cardiovascular mortality. These findings allow us to propose that modulation of calpain-1 activity is a potential therapeutic option for delaying age-associated organ pathology, particularly caused by the dysregulation of mineral ion homeostasis.
Assuntos
Envelhecimento , Glucuronidase/deficiência , Sulfonamidas/farmacologia , Animais , Calpaína/antagonistas & inibidores , Calpaína/metabolismo , Avaliação Pré-Clínica de Medicamentos , Feminino , Fator de Crescimento de Fibroblastos 23 , Fatores de Crescimento de Fibroblastos/sangue , Glucuronidase/genética , Humanos , Proteínas Klotho , Masculino , Camundongos Knockout , Fenótipo , Insuficiência Renal Crônica/tratamento farmacológico , Insuficiência Renal Crônica/genética , Insuficiência Renal Crônica/metabolismo , Sulfonamidas/uso terapêutico , Calcificação Vascular/sangue , Calcificação Vascular/tratamento farmacológicoRESUMO
BACKGROUND: Voltage-dependent block of the NMDA receptor by Mg2+ is thought to be central to the unique involvement of this receptor in higher brain functions. However, the in vivo role of the Mg2+ block in the mammalian brain has not yet been investigated, because brain-wide loss of the Mg2+ block causes perinatal lethality. In this study, we used a brain-region specific knock-in mouse expressing an NMDA receptor that is defective for the Mg2+ block in order to test its role in neural information processing. RESULTS: We devised a method to induce a single amino acid substitution (N595Q) in the GluN2A subunit of the NMDA receptor, specifically in the hippocampal dentate gyrus in mice. This mutation reduced the Mg2+ block at the medial perforant path-granule cell synapse and facilitated synaptic potentiation induced by high-frequency stimulation. The mutants had more stable hippocampal place fields in the CA1 than the controls did, and place representation showed lower sensitivity to visual differences. In addition, behavioral tests revealed that the mutants had a spatial working memory deficit. CONCLUSIONS: These results suggest that the Mg2+ block in the dentate gyrus regulates hippocampal spatial information processing by attenuating activity-dependent synaptic potentiation in the dentate gyrus.
Assuntos
Giro Denteado/metabolismo , Magnésio/farmacologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Envelhecimento/fisiologia , Animais , Sequência de Bases , Giro Denteado/efeitos dos fármacos , Giro Denteado/patologia , Giro Denteado/fisiopatologia , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Marcação de Genes , Integrases/metabolismo , Camundongos , Camundongos Mutantes Neurológicos , Dados de Sequência Molecular , Proteínas Mutantes/metabolismo , Neurogênese/efeitos dos fármacos , Plasticidade Neuronal/efeitos dos fármacos , Especificidade de Órgãos/efeitos dos fármacos , Subunidades Proteicas/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismoRESUMO
Embryogenesis in placental mammals is sustained by exquisite interplay between the embryo proper and placenta. UTF1 is a developmentally regulated gene expressed in both cell lineages. Here, we analyzed the consequence of loss of the UTF1 gene during mouse development. We found that homozygous UTF1 mutant newborn mice were significantly smaller than wild-type or heterozygous mutant mice, suggesting that placental insufficiency caused by the loss of UTF1 expression in extra-embryonic ectodermal cells at least in part contributed to this phenotype. We also found that the effects of loss of UTF1 expression in embryonic stem cells on their pluripotency were very subtle. Genome structure and sequence comparisons revealed that the UTF1 gene exists only in placental mammals. Our analyses of a family of genes with homology to UTF1 revealed a possible mechanism by which placental mammals have evolved the UTF1 genes.
Assuntos
Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Desenvolvimento Embrionário/genética , Transativadores/genética , Transativadores/metabolismo , Sequência de Aminoácidos , Animais , Proteínas Cromossômicas não Histona/química , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Evolução Molecular , Feminino , Técnicas de Inativação de Genes , Marcação de Genes , Genótipo , Camundongos , Dados de Sequência Molecular , Mutação , Fenótipo , Filogenia , Placenta/embriologia , Placenta/metabolismo , Gravidez , Alinhamento de Sequência , Transativadores/químicaRESUMO
We found adult human stem cells that can generate, from a single cell, cells with the characteristics of the three germ layers. The cells are stress-tolerant and can be isolated from cultured skin fibroblasts or bone marrow stromal cells, or directly from bone marrow aspirates. These cells can self-renew; form characteristic cell clusters in suspension culture that express a set of genes associated with pluripotency; and can differentiate into endodermal, ectodermal, and mesodermal cells both in vitro and in vivo. When transplanted into immunodeficient mice by local or i.v. injection, the cells integrated into damaged skin, muscle, or liver and differentiated into cytokeratin 14-, dystrophin-, or albumin-positive cells in the respective tissues. Furthermore, they can be efficiently isolated as SSEA-3(+) cells. Unlike authentic ES cells, their proliferation activity is not very high and they do not form teratomas in immunodeficient mouse testes. Thus, nontumorigenic stem cells with the ability to generate the multiple cell types of the three germ layers can be obtained through easily accessible adult human mesenchymal cells without introducing exogenous genes. These unique cells will be beneficial for cell-based therapy and biomedical research.
Assuntos
Células-Tronco Adultas/citologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Multipotentes/citologia , Adulto , Animais , Células da Medula Óssea/citologia , Agregação Celular , Diferenciação Celular , Proliferação de Células , Humanos , Transplante de Células-Tronco Mesenquimais , CamundongosRESUMO
Alpha-Klotho (alpha-Kl) and its homolog, beta-Klotho (beta-Kl) are key regulators of mineral homeostasis and bile acid/cholesterol metabolism, respectively. FGF15/ humanFGF19, FGF21, and FGF23, members of the FGF19 subfamily, are believed to act as circulating metabolic regulators. Analyses of functional interactions between alpha- and beta-Kl and FGF19 factors in wild-type, alpha-kl(-/-), and beta-kl(-/-) mice revealed a comprehensive regulatory scheme of mineral homeostasis involving the mutually regulated positive/negative feedback actions of alpha-Kl, FGF23, and 1,25(OH)(2)D and an analogous regulatory network composed of beta-Kl, FGF15/humanFGF19, and bile acids that regulate bile acid/cholesterol metabolism. Contrary to in vitro data, beta-Kl is not essential for FGF21 signaling in adipose tissues in vivo, because (i) FGF21 signals are transduced in the absence of beta-Kl, (ii) FGF21 could not be precipitated by beta-Kl, and (iii) essential phenotypes in Fgf21(-/-) mice (decreased expressions of Hsl and Atgl in WAT) were not replicated in beta-kl(-/-) mice. These findings suggest the existence of Klotho-independent FGF21 signaling pathway(s) where undefined cofactors are involved. One-to-one functional interactions such as alpha-Klotho/FGF23, beta-Klotho/FGF15 (humanFGF19), and undefined cofactor/FGF21 would result in tissue-specific signal transduction of the FGF19 subfamily.
Assuntos
Fatores de Crescimento de Fibroblastos/metabolismo , Glucuronidase/metabolismo , Transdução de Sinais , Tecido Adiposo/metabolismo , Animais , Ácidos e Sais Biliares/metabolismo , Fator de Crescimento de Fibroblastos 23 , Fatores de Crescimento de Fibroblastos/genética , Regulação da Expressão Gênica , Glucuronidase/deficiência , Proteínas Klotho , Fígado/metabolismo , Camundongos , Camundongos Knockout , Ligação Proteica , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Vitamina D/metabolismoRESUMO
alpha-klotho was identified as a gene associated with premature aging-like phenotypes characterized by short lifespan. In mice, we found the molecular association of alpha-Klotho (alpha-Kl) and Na+,K+-adenosine triphosphatase (Na+,K+-ATPase) and provide evidence for an increase of abundance of Na+,K+-ATPase at the plasma membrane. Low concentrations of extracellular free calcium ([Ca2+]e) rapidly induce regulated parathyroid hormone (PTH) secretion in an alpha-Kl- and Na+,K+-ATPase-dependent manner. The increased Na+ gradient created by Na+,K+-ATPase activity might drive the transepithelial transport of Ca2+ in cooperation with ion channels and transporters in the choroid plexus and the kidney. Our findings reveal fundamental roles of alpha-Kl in the regulation of calcium metabolism.
Assuntos
Cálcio/metabolismo , Glucuronidase/fisiologia , Homeostase , Animais , Cálcio/líquido cefalorraquidiano , Membrana Celular/enzimologia , Membrana Celular/metabolismo , Plexo Corióideo/metabolismo , Citoplasma/enzimologia , Citoplasma/metabolismo , Retículo Endoplasmático/metabolismo , Endossomos/metabolismo , Inibidores Enzimáticos/farmacologia , Retroalimentação Fisiológica , Glucuronidase/genética , Glucuronidase/metabolismo , Complexo de Golgi/metabolismo , Células HeLa , Humanos , Transporte de Íons , Rim/enzimologia , Rim/metabolismo , Proteínas Klotho , Camundongos , Ouabaína/farmacologia , Glândulas Paratireoides/enzimologia , Glândulas Paratireoides/metabolismo , Hormônio Paratireóideo/metabolismo , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , ATPase Trocadora de Sódio-Potássio/metabolismoRESUMO
Despite fast protein degradation in muscles, protein concentrations remain constant during differentiation and maintenance of muscle tissues. Myogenin, a basic helix-loop-helix-type myogenic transcription factor, plays a critical role through transcriptional activation in myogenesis as well as muscle maintenance. TBP-interacting protein 120/cullin-associated neddylation-dissociated (TIP120/CAND) is known to bind to cullin and negatively regulate SCF (Skp1-Cullin1-F-box protein) ubiquitin ligase, although its physiological role has not been elucidated. We have identified a muscle-specific isoform of TIP120, named TIP120B/CAND2. In this study, we found that TIP120B is not only induced in association with myogenic differentiation but also actively accelerates the myogenic differentiation of C2C12 cells. Although myogenin is a short lived protein and is degraded by a ubiquitin-proteasome system, TIP120B suppressed its ubiquitination and subsequent degradation of myogenin. TIP120B bound to cullin family proteins, especially Cullin 1 (CUL1), and was associated with SCF complex in cells. It was demonstrated that myogenin was also associated with SCF and that CUL1 small interference RNA treatment inhibited ubiquitination of myogenin and stabilized it. TIP120B was found to break down the SCF-myogenin complex. Consequently suppression of SCF-dependent ubiquitination of myogenin by TIP120B, which leads to stabilization of myogenin, can account for the TIP120B-directed accelerated differentiation of C2C12 cells. TIP120B is proposed to be a novel regulator for myogenesis.
Assuntos
Proteínas Musculares/metabolismo , Miogenina/química , Fator de Células-Tronco/metabolismo , Fatores de Transcrição/fisiologia , Ubiquitina/química , Animais , Diferenciação Celular , Linhagem Celular , Camundongos , Modelos Biológicos , Desenvolvimento Muscular , Complexo de Endopeptidases do Proteassoma/metabolismo , Isoformas de Proteínas , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Fatores de Transcrição/química , Transfecção , Ubiquitina/metabolismoRESUMO
klotho-Deficient mice exhibit a syndrome resembling human premature ageing, with multiple pathological phenotypes in tissues including reproductive organs. It was proposed that Klotho might possess the hormonal effects on many organs. In this study, the female reproductive system of klotho mice was examined to reveal the mechanism that brought the female sterility by histological and molecular approaches. We observed cessation of ovarian follicular maturation at the preantral stage and the presence of numerous atretic ovarian follicles and atrophic uteri. In situ hybridization analysis revealed that LH receptor and aromatase P450 were not expressed in the ovaries. These results suggest the impairment of gonadal development during the antral transition process. We next addressed the responsible organs for the failure of antral transition. Transplantation of klotho ovaries to wild-type mice resulted in the ability to bear offspring. Administration of FSH or GnRH induced advanced maturation of ovaries and uteri in klotho mice. These results indicate that the female reproductive organs in klotho mice are potentially functional and that klotho gene deficiency leads to the atrophy of reproductive organs via impairment of the hypothalamic-pituitary axis. Absence of the estrus cycle and constant low trends of both FSH and LH levels were found in female klotho mice. Immunohistochemical analysis revealed that the production of both FSH and LH were decreased in pituitary gland. Taken together, our findings suggest the involvement of klotho in the regulatory control of pituitary hormones.
Assuntos
Proteínas de Membrana/deficiência , Proteínas de Membrana/fisiologia , Ovário/patologia , Animais , Atrofia , Modelos Animais de Doenças , Feminino , Hormônio Foliculoestimulante/sangue , Glucuronidase , Humanos , Proteínas Klotho , Hormônio Luteinizante/sangue , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Knockout , Folículo Ovariano/patologia , Progéria/genéticaRESUMO
We have generated a line of mutant mouse that lacks betaKlotho, a protein that structurally resembles Klotho. The synthesis and excretion of bile acids were found to be dramatically elevated in these mutants, and the expression of 2 key bile acid synthase genes, cholesterol 7alpha-hydroxylase (Cyp7a1) and sterol 12alpha-hydroxylase (Cyp8b1), was strongly upregulated. Nuclear receptor pathways and the enterohepatic circulation, which regulates bile acid synthesis, seemed to be largely intact; however, bile acid-dependent induction of the small heterodimer partner (SHP) NR0B2, a common negative regulator of Cyp7a1 and Cyp8b1, was significantly attenuated. The expression of Cyp7a1 and Cyp8b1 is known to be repressed by dietary bile acids via both SHP-dependent and -independent regulations. Interestingly, the suppression of Cyp7a1 expression by dietary bile acids was impaired, whereas that of Cyp8b1 expression was not substantially altered in betaklotho mice. Therefore, betaKlotho may stand as a novel contributor to Cyp7a1-selective regulation. Additionally, betaKlotho-knockout mice exhibit resistance to gallstone formation, which suggests the potential future clinical relevance of the betaKlotho system.
Assuntos
Ácidos e Sais Biliares/biossíntese , Ácidos e Sais Biliares/metabolismo , Regulação Enzimológica da Expressão Gênica , Proteínas de Membrana/metabolismo , Animais , Ácidos e Sais Biliares/genética , Colesterol 7-alfa-Hidroxilase/biossíntese , Ativação Enzimática/genética , Cálculos Biliares/genética , Cálculos Biliares/metabolismo , Regulação Enzimológica da Expressão Gênica/genética , Proteínas Klotho , Circulação Hepática , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Receptores Citoplasmáticos e Nucleares/metabolismo , Esteroide 12-alfa-Hidroxilase/biossínteseRESUMO
Sonic hedgehog (Shh), an organizing signal from ventral midline structures, is essential for the induction and maintenance of many ventral cell types in the embryonic neural tube. Olig1 and Olig2 are related basic helix-loop-helix factors induced by Shh in the ventral neural tube. Although expression analyses and gain-of-function experiments suggested that these factors were involved in motoneuron and oligodendrocyte development, they do not clearly define the functional differences between Olig1 and Olig2. We generated mice with a homozygous inactivation of Olig2. These mice did not feed and died on the day of birth. In the spinal cord of the mutant mice, motoneurons are largely eliminated and oligodendrocytes are not produced. Olig2(-/-) neuroepithelial cells in the ventral spinal cord failed to differentiate into motoneurons or oligodendrocytes and expressed an astrocyte marker, S100beta, at the time of oligodendrogenesis. Olig1 or Olig3, other family members, were expressed in the descendent cells that should have expressed Olig2. We concluded that Olig2 is an essential transcriptional regulator in motoneuron and oligodendrocyte development. Our data provide the first evidence that a single gene mutation leads to the loss of two cell types, motoneuron and oligodendrocyte.