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1.
Intern Med ; 63(6): 857-860, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-37587040

RESUMO

Paraneoplastic cerebellar degeneration (PCD) is a paraneoplastic neurological syndrome that is rarely accompanied by seropositivity with a combination of multiple antibodies. We herein report a 50-year-old man with PCD accompanied by small-cell lung cancer (SCLC). This patient was seropositive for anti-glutamic acid decarboxylase 65, anti-SRY-related HMG-box gene 1 and anti-voltage-gated calcium channel antibodies. After chemoradiation therapy without immunotherapy, cerebellar ataxia of the trunk and limbs markedly improved, along with a notable amelioration of SCLC. This case suggests that tumor therapy should be started immediately and that a panel of anti-neuronal antibodies should be evaluated when PCD with SCLC is suspected.


Assuntos
Neoplasias Pulmonares , Degeneração Paraneoplásica Cerebelar , Carcinoma de Pequenas Células do Pulmão , Masculino , Humanos , Pessoa de Meia-Idade , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/terapia , Carcinoma de Pequenas Células do Pulmão/complicações , Carcinoma de Pequenas Células do Pulmão/terapia , Anticorpos , Quimiorradioterapia , Autoanticorpos
2.
J Am Chem Soc ; 145(35): 19177-19181, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37623927

RESUMO

Multiple proton transfer (PT) controllable by external stimuli plays a crucial role in fundamental chemistry, biological activity, and material science. However, in crystalline systems, controlling multiple PT, which results in a distinct protonation state, remains challenging. In this study, we developed a novel tridentate ligand and iron(II) complex with a short hydrogen bond (HB) that exhibits a PT-coupled spin transition (PCST). Single-crystal X-ray and neutron diffraction measurements revealed that the positions of the two protons in the complex can be controlled by temperature and photoirradiation based on the thermal- and photoinduced PCST. The obtained results suggest that designing molecules that form short HBs is a promising approach for developing multiple PT systems in crystals.

3.
Cell Rep ; 42(2): 111940, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36719796

RESUMO

Choline supplies methyl groups for regeneration of methionine and the methyl donor S-adenosylmethionine in the liver. Here, we report that the catabolism of membrane phosphatidylcholine (PC) into water-soluble glycerophosphocholine (GPC) by the phospholipase/lysophospholipase PNPLA8-PNPLA7 axis enables endogenous choline stored in hepatic PC to be utilized in methyl metabolism. PNPLA7-deficient mice show marked decreases in hepatic GPC, choline, and several metabolites related to the methionine cycle, accompanied by various signs of methionine insufficiency, including growth retardation, hypoglycemia, hypolipidemia, increased energy consumption, reduced adiposity, increased fibroblast growth factor 21 (FGF21), and an altered histone/DNA methylation landscape. Moreover, PNPLA8-deficient mice recapitulate most of these phenotypes. In contrast to wild-type mice fed a methionine/choline-deficient diet, both knockout strains display decreased hepatic triglyceride, likely via reductions of lipogenesis and GPC-derived glycerol flux. Collectively, our findings highlight the biological importance of phospholipid catabolism driven by PNPLA8/PNPLA7 in methyl group flux and triglyceride synthesis in the liver.


Assuntos
Fígado , Lisofosfolipase , Metionina , Fosfatidilcolinas , Animais , Camundongos , Colina/metabolismo , Glicerilfosforilcolina/metabolismo , Fígado/metabolismo , Metionina/metabolismo , Racemetionina/metabolismo , S-Adenosilmetionina/metabolismo , Triglicerídeos/metabolismo , Lisofosfolipase/genética , Lisofosfolipase/metabolismo , Fosfatidilcolinas/metabolismo
4.
BMC Neurol ; 22(1): 193, 2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35614401

RESUMO

BACKGROUND: Cerebrotendinous xanthomatosis (CTX) is an autosomal-recessive lipid storage disorder caused by mutations in the CYP27A1 gene encoding the key enzyme in the bile acid synthesis, sterol 27-hydroxylase. Here, we report two Japanese CTX siblings with a novel compound heterozygous CYP27A1 mutation, showing different clinical phenotypes and responses to chenodeoxycholic acid (CDCA) therapy. CASE PRESENTATION: The proband, a 32-year-old man, who had chronic diarrhea, bilateral cataracts, and xanthomas, demonstrated progressive neurological manifestations including ataxia, and spastic paraplegia during a 5-year follow-up period despite normalization of serum cholestanol after initiation of CDCA treatment. He also exhibited cognitive decline although improvement had been observed at the beginning of treatment. Follow-up brain magnetic resonance imaging (MRI) revealed pronounced progressive atrophy in the cerebellum, in addition to expanding hyperintense lesions in the dentate nuclei, posterior limb of the internal capsule, cerebral peduncles, and inferior olives on T2-weighted images. In contrast, the two-year-younger sister of the proband presented with chronic diarrhea, cataracts, xanthomas, and intellectual disability but no other neurological symptoms at the time of diagnosis. CDCA treatment lead to improvement of cognitive function and there were no characteristic CTX-related MRI features during the follow-up period. The siblings shared a paternally inherited c.1420C > T mutation (p.Arg474Trp) and a maternally inherited novel c.1176_1177delGA mutation, predicting p.(Glu392Asp*20). CONCLUSIONS: Our cases suggest that early diagnosis and subsequent initiation of CDCA treatment are crucial before the appearance of characteristic MRI findings and severe neurological manifestations related to CTX. Further studies are required to elucidate mechanisms responsible for the clinical diversity of CTX and prognostic factors for long-term outcomes following initiation of CDCA treatment.


Assuntos
Catarata , Xantomatose Cerebrotendinosa , Xantomatose , Catarata/genética , Ácido Quenodesoxicólico/uso terapêutico , Colestanotriol 26-Mono-Oxigenase/genética , Colestanotriol 26-Mono-Oxigenase/uso terapêutico , Diarreia/tratamento farmacológico , Humanos , Japão , Masculino , Mutação/genética , Irmãos , Xantomatose/tratamento farmacológico , Xantomatose Cerebrotendinosa/complicações , Xantomatose Cerebrotendinosa/tratamento farmacológico , Xantomatose Cerebrotendinosa/genética
5.
J Neurosci ; 41(35): 7479-7491, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34290084

RESUMO

Cell-to-cell transmission of α-synuclein (α-syn) pathology is considered to underlie the spread of neurodegeneration in Parkinson's disease (PD). Previous studies have demonstrated that α-syn is secreted under physiological conditions in neuronal cell lines and primary neurons. However, the molecular mechanisms that regulate extracellular α-syn secretion remain unclear. In this study, we found that inhibition of monoamine oxidase-B (MAO-B) enzymatic activity facilitated α-syn secretion in human neuroblastoma SH-SY5Y cells. Both inhibition of MAO-B by selegiline or rasagiline and siRNA-mediated knock-down of MAO-B facilitated α-syn secretion. However, TVP-1022, the S-isomer of rasagiline that is 1000 times less active, failed to facilitate α-syn secretion. Additionally, the MAO-B inhibition-induced increase in α-syn secretion was unaffected by brefeldin A, which inhibits endoplasmic reticulum (ER)/Golgi transport, but was blocked by probenecid and glyburide, which inhibit ATP-binding cassette (ABC) transporter function. MAO-B inhibition preferentially facilitated the secretion of detergent-insoluble α-syn protein and decreased its intracellular accumulation under chloroquine-induced lysosomal dysfunction. Moreover, in a rat model (male Sprague Dawley rats) generated by injecting recombinant adeno-associated virus (rAAV)-A53T α-syn, subcutaneous administration of selegiline delayed the striatal formation of Ser129-phosphorylated α-syn aggregates, and mitigated loss of nigrostriatal dopaminergic neurons. Selegiline also delayed α-syn aggregation and dopaminergic neuronal loss in a cell-to-cell transmission rat model (male Sprague Dawley rats) generated by injecting rAAV-wild-type α-syn and externally inoculating α-syn fibrils into the striatum. These findings suggest that MAO-B inhibition modulates the intracellular clearance of detergent-insoluble α-syn via the ABC transporter-mediated non-classical secretion pathway, and temporarily suppresses the formation and transmission of α-syn aggregates.SIGNIFICANCE STATEMENT The identification of a neuroprotective agent that slows or stops the progression of motor impairments is required to treat Parkinson's disease (PD). The process of α-synuclein (α-syn) aggregation is thought to underlie neurodegeneration in PD. Here, we demonstrated that pharmacological inhibition or knock-down of monoamine oxidase-B (MAO-B) in SH-SY5Y cells facilitated α-syn secretion via a non-classical pathway involving an ATP-binding cassette (ABC) transporter. MAO-B inhibition preferentially facilitated secretion of detergent-insoluble α-syn protein and reduced its intracellular accumulation under chloroquine-induced lysosomal dysfunction. Additionally, MAO-B inhibition by selegiline protected A53T α-syn-induced nigrostriatal dopaminergic neuronal loss and suppressed the formation and cell-to-cell transmission of α-syn aggregates in rat models. We therefore propose a new function of MAO-B inhibition that modulates α-syn secretion and aggregation.


Assuntos
Neurônios Dopaminérgicos/efeitos dos fármacos , Indanos/uso terapêutico , Inibidores da Monoaminoxidase/uso terapêutico , Monoaminoxidase/fisiologia , Transtornos Parkinsonianos/tratamento farmacológico , Agregação Patológica de Proteínas/tratamento farmacológico , Selegilina/uso terapêutico , alfa-Sinucleína/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Morte Celular , Linhagem Celular Tumoral , Corpo Estriado/metabolismo , Corpo Estriado/patologia , Meios de Cultivo Condicionados , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Técnicas de Silenciamento de Genes , Vetores Genéticos/administração & dosagem , Humanos , Injeções , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Masculino , Monoaminoxidase/genética , Mutação de Sentido Incorreto , Neuroblastoma , Agregação Patológica de Proteínas/genética , Agregação Patológica de Proteínas/metabolismo , Transporte Proteico/efeitos dos fármacos , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/farmacologia , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/toxicidade , Substância Negra/metabolismo , Substância Negra/patologia , alfa-Sinucleína/genética
6.
JAMA Neurol ; 78(7): 853-863, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34047774

RESUMO

Importance: Repeat expansion of CGG in LRP12 has been identified as the causative variation of oculopharyngodistal myopathy (OPDM). However, to our knowledge, the clinicopathologic features of OPDM with CGG repeat expansion in LRP12 (hereafter referred to as OPDM_LRP12) remain unknown. Objective: To identify and characterize the clinicopathologic features of patients with OPDM_LRP12. Design, Setting, and Participants: This case series included 208 patients with a clinical or clinicopathologic diagnosis of oculopharyngeal muscular dystrophy (OPDM) from January 1, 1978, to December 31, 2020. Patients with GCN repeat expansions in PABPN1 were excluded from the study. Repeat expansions of CGG in LRP12 were screened by repeat primed polymerase chain reaction and/or Southern blot. Main Outcomes and Measures: Clinical information, muscle imaging data obtained by either computed tomography or magnetic resonance imaging, and muscle pathologic characteristics. Results: Sixty-five Japanese patients with OPDM (40 men [62%]; mean [SD] age at onset, 41.0 [10.1] years) from 59 families with CGG repeat expansions in LRP12 were identified. This represents the most common OPDM subtype among all patients in Japan with genetically diagnosed OPDM. The expansions ranged from 85 to 289 repeats. A negative correlation was observed between the repeat size and the age at onset (r2 = 0.188, P = .001). The most common initial symptoms were ptosis and muscle weakness, present in 24 patients (37%). Limb muscle weakness was predominantly distal in 53 of 64 patients (83%), but 2 of 64 patients (3%) had predominantly proximal muscle weakness. Ptosis was observed in 62 of 64 patients (97%), and dysphagia or dysarthria was observed in 63 of 64 patients (98%). A total of 21 of 64 patients (33%) had asymmetric muscle weakness. Aspiration pneumonia was seen in 11 of 64 patients (17%), and 5 of 64 patients (8%) required mechanical ventilation. Seven of 64 patients (11%) developed cardiac abnormalities, and 5 of 64 patients (8%) developed neurologic abnormalities. Asymmetric muscle involvement was detected on computed tomography scans in 6 of 27 patients (22%) and on magnetic resonance imaging scans in 4 of 15 patients (27%), with the soleus and the medial head of the gastrocnemius being the worst affected. All 42 muscle biopsy samples showed rimmed vacuoles. Intranuclear tubulofilamentous inclusions were observed in only 1 of 5 patients. Conclusions and Relevance: This study suggests that OPDM_LRP12 is the most frequent OPDM subtype in Japan and is characterized by oculopharyngeal weakness, distal myopathy that especially affects the soleus and gastrocnemius muscles, and rimmed vacuoles in muscle biopsy.


Assuntos
Expansão das Repetições de DNA , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Distrofias Musculares/diagnóstico , Adolescente , Adulto , Feminino , Humanos , Japão , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Debilidade Muscular , Músculo Esquelético/patologia , Linhagem , Adulto Jovem
7.
Cell Rep ; 31(5): 107579, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32375030

RESUMO

Polyunsaturated fatty acids (PUFAs) confer health benefits by preventing inflammation and obesity and by increasing thermogenesis in brown and beige adipocytes. As well as being supplied exogenously as nutrients, PUFAs are largely stored in membrane glycerophospholipids and released by phospholipase A2s (PLA2s). However, the molecular identity of the PLA2 subtype(s) that supplies endogenous PUFAs for metabolic homeostasis remains unclear. Here we show that PLA2G2D, a secreted PLA2 isoform, is constitutively expressed in M2-type macrophages in white adipose tissue (WAT) and shows a reciprocal correlation with obesity. Studies using global and macrophage-specific Pla2g2d-deficient mice reveal that PLA2G2D increases energy expenditure and thermogenesis by facilitating adipocyte browning, thereby ameliorating diet-induced obesity, insulin resistance, and WAT inflammation. Mechanistically, PLA2G2D constitutively supplies a pool of PUFAs, ω3 in particular, in WAT. Thus, our present findings underscore the contribution of the macrophage-driven PLA2G2D-ω3 PUFA axis to metabolic health.


Assuntos
Tecido Adiposo Branco/metabolismo , Ácidos Graxos Insaturados/metabolismo , Fosfolipases A2 do Grupo II/metabolismo , Fosfolipases/metabolismo , Adipócitos/metabolismo , Tecido Adiposo Marrom/metabolismo , Animais , Metabolismo Energético , Ácidos Graxos Ômega-3/metabolismo , Inflamação/metabolismo , Macrófagos/metabolismo , Camundongos , Obesidade/metabolismo , Termogênese/fisiologia
8.
Angew Chem Int Ed Engl ; 59(35): 14781-14787, 2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32452130

RESUMO

A proton-electron coupling system, exhibiting unique bistability or multistability of the protonated state, is an attractive target for developing new switchable materials based on proton dynamics. Herein, we present an iron(II) hydrazone crystalline compound, which displays the stepwise transition and bistability of proton transfer at the crystal level. These phenomena are realized through the coupling with spin transition. Although the multi-step transition with hysteresis has been observed in various systems, the corresponding behavior of proton transfer has not been reported in crystalline systems; thus, the described iron(II) complex is the first example. Furthermore, because proton transfer occurs only in one of the two ligands and π electrons redistribute in it, the dipole moment of the iron(II) complexes changes with the proton transfer, wherein the total dipole moment in the crystal was canceled out owing to the antiferroelectric-like arrangement.

9.
Rinsho Shinkeigaku ; 59(6): 339-344, 2019 Jun 22.
Artigo em Japonês | MEDLINE | ID: mdl-31142706

RESUMO

An 80-year-old male with prostatic adenocarcinoma who was treated with orchiectomy presented dysarthria and difficulty in walking. His symptoms subacutely progressed. Seven days later, he was non-ambulatory and was admitted to our hospital. He had poor vision and cerebellar ataxia of the lower extremities; however, his muscle strength, tendon reflexes, and sensory functions were preserved. Paraneoplastic retinopathy was diagnosed based on electroretinographic and visual field defect. Further, brain and spinal MRI, cerebral spinal fluid, and nerve conduction assessments were normal. These symptoms were followed by consciousness disturbance and respiratory failure; consequently, he required non-invasive positive pressure ventilation (NPPV) and tube feeding. Steroid pulse therapy and plasma exchange (PE) were performed. In response to the therapy, all these symptoms were relieved, and NPPV and tube feeding were withdrawn. However, the same symptoms occurred additional three times throughout the course of approximately 1 year. Each time, PE was the most effective treatment. Although paraneoplastic neurological syndrome associated with prostatic cancer is rare, immunotherapy could be a therapeutic choice to relive symptoms.


Assuntos
Ataxia Cerebelar/terapia , Síndromes Paraneoplásicas/terapia , Troca Plasmática , Insuficiência Respiratória/terapia , Adenocarcinoma , Idoso de 80 Anos ou mais , Evolução Fatal , Humanos , Masculino , Metilprednisolona/administração & dosagem , Neoplasias da Próstata , Pulsoterapia , Recidiva , Resultado do Tratamento
10.
Chemistry ; 25(28): 6920-6927, 2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-30776310

RESUMO

The pseudo-polyrotaxane structure of [(H-bpy+ )- (DB-24-crown-8)]∞ (H-bpy+ = monoprotonated 4,4-bipyridinium; DB-24-crown-8 = dibenzo-24-crown-8) has been incorporated into the anion radical salt [Ni(dmit)2 ]- (dmit2- = 1,3-dithiole-2-thione-4,5-dithiolate). (H-bpy+ )(DB-24-crown-8)[Ni(dmit)2 ]- crystallized as two polymorphs, crystals 1 and 2. Crystal 1 was found to have a lower density and looser packing structure in which H-bpy+ forms a one-dimensional hydrogen-bonding chain that passes though the crown ether ring of DB-24-crown-8. DB-24-crown-8 adopts a U-shaped conformation in which two phenylene rings sandwich one of the pyridyl rings of H-bpy+ to stabilize the structure. The [Ni(dmit)2 ]- anions are arranged in a layer parallel to the (10) plane with uniform side-by-side interactions. A structural phase transition was observed at 235 K, accompanied by ordering of the polyrotaxane structure. In crystal 1, at 173 K, H-bpy+ is twisted around the central C-C bond, which perturbs the arrangement of [Ni(dmit)2 ]- through short C-H⋅⋅⋅S contacts. As a result, the semiconducting behavior, with an activation energy of 0.21 eV, becomes insulating below 235 K. The crystal exhibits ferromagnetic interactions because of the weak side-by-side interactions between [Ni(dmit)2 ]- anions. Crystal 2 has a similar pseudo-polyrotaxane structure but showed no phase transition. This suggests that the looser crystal packing in crystal 1 induces the structural change of the pseudo-polyrotaxane, perturbing the electron system of [Ni(dmit)2 ]- .

11.
J Neurol Sci ; 397: 129-134, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30616055

RESUMO

OBJECTIVE: To examine whether cognitive impairment, deep white matter hyperintensity (DWMH) on brain MRI, and shorter telomere length would be predictors of mortality in community-dwelling Japanese elderly. METHODS: We followed 259 individuals (74% of all the residents at age 70) from age 70 to 83 years. The mean observation period was 133 ±â€¯34 months. The key clinical characteristics examined included DWMH on brain MRI and cognitive function. Telomere length was also measured in 81 subjects. Both univariate and multivariate analyses were performed. RESULTS: Of the 259 subjects, 69 subjects (30 men, 39 women; 26.6%) died during the follow-up period. Cognitive impairment, smoking habits, diabetes mellitus, and moderate to severe DWMH were significant predictors of total mortality in univariate analysis. However, only cognitive impairment and moderate to severe DWMH remained as significant independent predictors of death in multivariate analysis. The rate of mortality increased with additional number of risk factors (cognitive impairment and DWMH). The total mortality of subjects with both cognitive impairment and DWMH was 71.4%. The median telomere length was 7.8 kb in the deceased and 8.2 kb in the living subjects. The deceased subjects had significantly shorter telomere length (P = .0025) than the living subjects. Telomere length with moderate to severe DWMH was higher than without moderate to severe DWMH on brain MRI (P = .017). CONCLUSIONS: The present study revealed that cognitive impairment, DWMH, and shorter telomere length were significant predictors of total mortality in the community-dwelling Japanese elderly. Furthermore, the combination of cognitive impairment and DWMH increased the mortality rate, as compared with a single risk factor. It is also clarified that a significant difference was present in telomere length by severity of DWMH.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico , Telômero , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/mortalidade , Cognição/fisiologia , Disfunção Cognitiva/mortalidade , Feminino , Humanos , Vida Independente , Japão/epidemiologia , Imageamento por Ressonância Magnética , Masculino , Estudos Prospectivos , Fatores de Risco , Taxa de Sobrevida
12.
Biol Pharm Bull ; 41(5): 770-776, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29709914

RESUMO

Many natural products that inhibit melanogenesis, freckles, and hyperpigmentation have been selectively used in cosmetics because melanogenesis is linked to the multiple biogenesis cascades of melanin synthesis. However, some of these compounds have side effects that may result in their restriction in the future. We report here the isolation and structural elucidation of compounds extracted from Mansonia gagei and evaluate their activity on melanogenesis inhibition. We isolated five known compounds from M. gagei and identified them as mansonone E (1), mansorin I (2), populene F (3), mansonone G (4), and mansorin B (5). After evaluating the five compounds for cytotoxicity against B16 cells and inhibitory activity on α-melanocyte-stimulating hormone (α-MSH) induced melanogenesis, we determined that the cytotoxicity and melanogenesis-inhibitory effect of 1 were relatively low and high, respectively. Next, the effect of 1 on the expression of melanogenesis-related proteins was assessed; it was confirmed that 1 dose-dependently inhibited the expression levels of tyrosinase, tyrosinase-related protein 1 (TRP-1), TRP-2, cAMP response element binding protein (CREB), and microphthalmia-associated transcription factor (MITF) which were increased after stimulation by α-MSH. Furthermore, the effects of 1 on the phosphorylation levels of intracellular signaling pathway-related proteins were evaluated, and it was found that 1 dose-dependently rescued the phosphorylation of Akt and p38 mitogen-activated protein kinases (MAPK), which were up- or down-regulated after stimulation by α-MSH. In contrast, treatment with the phosphoinositide 3-kinase (PI3K)/Akt inhibitor wortmannin enhanced melanogenesis inhibition by mansonone E. Cumulatively, the data suggest that 1 suppresses α-MSH-induced melanogenesis in B16 cells by inhibiting both phosphorylation in the PI3K/Akt pathway and the expression of melanogenesis-related proteins.


Assuntos
Malvaceae , Melaninas/metabolismo , Melanoma Experimental/metabolismo , Naftoquinonas/farmacologia , Sesquiterpenos/farmacologia , alfa-MSH/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Casca de Planta , Extratos Vegetais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos
13.
Acta Neuropathol Commun ; 5(1): 48, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28619113

RESUMO

Parkinson's disease (PD) is characterized neuropathologically by intracellular aggregates of fibrillar α-synuclein, termed Lewy bodies (LBs). Approximately 90% of α-synuclein deposited as LBs is phosphorylated at Ser129 in brains with PD. In contrast, only 4% of total α-synuclein is phosphorylated at Ser129 in brains with normal individuals. It is unclear why extensive phosphorylation occurs in the pathological process of PD. To address this issue, we investigated a mechanism and role of Ser129-phosphorylation in regulating accumulation of α-synuclein. In CHO cells, the levels of Ser129-phosphorylated soluble α-synuclein were maintained constantly to those of total α-synuclein in intracellular and extracellular spaces. In SH-SY5Y cells and rat primary cortical neurons, mitochondrial impairment by rotenone or MPP+ enhanced Ser129-phosphorylation through increased influx of extracellular Ca2+. This elevation was suppressively controlled by targeting Ser129-phosphorylated α-synuclein to the proteasome pathway. Rotenone-induced insoluble α-synuclein was also targeted by Ser129-phosphoryation to the proteasome pathway. Experiments with epoxomicin and chloroquine showed that proteasomal targeting of insoluble Ser129-phosphorylated α-synuclein was enhanced under lysosome inhibition and it reduced accumulation of insoluble total α-synuclein. However, in a rat AAV-mediated α-synuclein overexpression model, there was no difference in the number of total α-synuclein aggregates between A53T mutant and A53T plus S129A double mutant α-synuclein, although Ser129-phosphorylated α-synuclein-positive aggregates were increased in rats expressing A53T α-synuclein. These findings suggest that Ser129-phosphorylation occurs against stress conditions, which increases influx of extracellular Ca2+, and it prevents accumulation of insoluble α-synuclein by evoking proteasomal clearance complementary to lysosomal one. However, Ser129-phosphorylation may provide an ineffective signal for degradation-resistant aggregates, causing extensive phosphorylation in aggregates.


Assuntos
alfa-Sinucleína/metabolismo , Animais , Células CHO , Cálcio/metabolismo , Cátions Bivalentes/metabolismo , Linhagem Celular Tumoral , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Cricetulus , Espaço Extracelular/metabolismo , Humanos , Mutação , Neurônios/metabolismo , Neurônios/patologia , Transtornos Parkinsonianos/metabolismo , Transtornos Parkinsonianos/patologia , Fosforilação , Complexo de Endopeptidases do Proteassoma/metabolismo , Agregação Patológica de Proteínas/metabolismo , Agregação Patológica de Proteínas/patologia , Ratos Sprague-Dawley , Estresse Fisiológico/fisiologia , alfa-Sinucleína/genética
14.
Angew Chem Int Ed Engl ; 56(27): 7779-7782, 2017 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-28561921

RESUMO

A dicopper(II) complex, stabilized by the bis(tpa) ligand 1,2-bis[2-[bis(2-pyridylmethyl)aminomethyl]-6-pyridyl]ethane (6-hpa), [Cu2 (µ-OH)(6-hpa)]3+ , was synthesized and structurally characterized. This complex catalyzed selective hydroxylation of benzene to phenol using H2 O2 , thus attaining large turnover numbers (TONs) and high H2 O2 efficiency. The TON after 40 hours for the phenol production exceeded 12000 in MeCN at 50 °C under N2 , the highest value reported for benzene hydroxylation with H2 O2 catalyzed by homogeneous complexes. At 22 % benzene conversion, phenol (95.2 %) and p-benzoquinone (4.8 %) were produced. The mechanism of H2 O2 activation and benzene hydroxylation is proposed.

15.
Intern Med ; 55(14): 1911-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27432102

RESUMO

A 58-year-old woman with a 1-month history of right hand clumsiness and speaking difficulty was admitted to our hospital. A neurological examination revealed sensory aphasia and right hemiparesis. Her laboratory tests showed elevated serum levels of IgG and IgG4, pancytopenia, and liver dysfunction. The results of the imaging studies of her abdomen were compatible with sclerosing cholangitis. Brain MRI showed extensive signal abnormalities in the left hemisphere on T2-weighted and fluid-attenuated inversion recovery (FLAIR) images, extending from left internal capsule to the cerebral peduncle with an irregularly enhancing lesion in the left parietal lobe. A brain biopsy revealed lymphocyte and plasma cell infiltration and reactive gliosis. Most of the plasma cells were IgG positive; however, IgG4-positive plasma cells were sparsely observed. After the initiation of betamethasone treatment, her symptoms and the brain MRI abnormalities showed significant improvement. The brain biopsy results did not meet the current criteria of IgG4-related disease. This is the first reported case of a tumefactive lesion of the brain parenchyma with serum IgG4 elevation, which was responsive to steroid treatment. The accumulation of a greater number of reports on the pathological investigation of cases of possible IgG4-related disease may help to elucidate the exact role of IgG4 in IgG4-related disorders.


Assuntos
Encefalopatias/complicações , Granuloma de Células Plasmáticas/complicações , Hipergamaglobulinemia/complicações , Imunoglobulina G/sangue , Biópsia , Encefalopatias/diagnóstico , Colangite Esclerosante/diagnóstico por imagem , Feminino , Granuloma de Células Plasmáticas/diagnóstico , Humanos , Hepatopatias/complicações , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade
16.
Biochim Biophys Acta ; 1861(9 Pt A): 1083-1095, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27317983

RESUMO

Adipogenesis is the process of differentiation of immature mesenchymal stem cells into adipocytes. Elucidation of the mechanisms that regulate adipocyte differentiation is key for the development of novel therapies for the control of obesity and related comorbidities. Cytosolic group IVA phospholipase A2 (cPLA2α) is the pivotal enzyme in receptor-mediated arachidonic acid (AA) mobilization and attendant eicosanoid production. Using primary multipotent cells and cell lines predetermined to become adipocytes, we show here that cPLA2α displays a proadipogenic function that occurs very early in the adipogenic process. Interestingly, cPLA2α levels decrease during adipogenesis, but cPLA2α-deficient preadipocytes exhibit a reduced capacity to differentiate into adipocytes, which affects early and terminal adipogenic transcription factors. Additionally, the absence of the phospholipase alters proliferation and cell-cycle progression that takes place during adipogenesis. Preconditioning of preadipocytes with AA increases the adipogenic capacity of these cells. Moreover, animals deficient in cPLA2α show resistance to obesity when fed a high fat diet that parallels changes in the expression of adipogenic transcription factors of the adipose tissue. Collectively, these results show that preadipocyte cPLA2α activation is a hitherto unrecognized factor for adipogenesis in vitro and in vivo.


Assuntos
Adipogenia/genética , Diferenciação Celular/genética , Fosfolipases A2 do Grupo IV/genética , Obesidade/genética , Células 3T3-L1 , Adipócitos/metabolismo , Animais , Citosol/enzimologia , Dieta Hiperlipídica , Fosfolipases A2 do Grupo IV/metabolismo , Metabolismo dos Lipídeos/genética , Células-Tronco Mesenquimais/enzimologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Obesidade/patologia
17.
J Biol Chem ; 291(30): 15602-13, 2016 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-27226633

RESUMO

Recent studies using knock-out mice for various secreted phospholipase A2 (sPLA2) isoforms have revealed their non-redundant roles in diverse biological events. In the skin, group IIF sPLA2 (sPLA2-IIF), an "epidermal sPLA2" expressed in the suprabasal keratinocytes, plays a fundamental role in epidermal-hyperplasic diseases such as psoriasis and skin cancer. In this study, we found that group IIE sPLA2 (sPLA2-IIE) was expressed abundantly in hair follicles and to a lesser extent in basal epidermal keratinocytes in mouse skin. Mice lacking sPLA2-IIE exhibited skin abnormalities distinct from those in mice lacking sPLA2-IIF, with perturbation of hair follicle ultrastructure, modest changes in the steady-state expression of a subset of skin genes, and no changes in the features of psoriasis or contact dermatitis. Lipidomics analysis revealed that sPLA2-IIE and -IIF were coupled with distinct lipid pathways in the skin. Overall, two skin sPLA2s, hair follicular sPLA2-IIE and epidermal sPLA2-IIF, play non-redundant roles in distinct compartments of mouse skin, underscoring the functional diversity of multiple sPLA2s in the coordinated regulation of skin homeostasis and diseases.


Assuntos
Dermatite de Contato/enzimologia , Regulação Enzimológica da Expressão Gênica , Fosfolipases A2 do Grupo II/biossíntese , Folículo Piloso/enzimologia , Psoríase/enzimologia , Animais , Dermatite de Contato/genética , Dermatite de Contato/patologia , Epiderme/enzimologia , Epiderme/patologia , Fosfolipases A2 do Grupo II/genética , Folículo Piloso/patologia , Camundongos , Camundongos Knockout , Psoríase/genética , Psoríase/patologia
18.
Sci Rep ; 5: 14211, 2015 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-26381815

RESUMO

α-Synuclein deposited in Lewy bodies, a pathological hallmark of Parkinson's disease (PD), is highly phosphorylated at serine 129 (Ser129). In contrast, there is very little Ser129-phosphorylated α-synuclein in the normal brains. This difference suggests that Ser129-phosphorylation is involved in neurodegenerative processes of PD. However, the role of this modification remains unclear. One limiting factor for relevant biochemical analyses is that it is difficult to detect endogenous Ser129-phosphorylated α-synuclein by western blotting, because α-synuclein monomers detached from the transferred membrane during incubation. Here, we reported that combination fixation of the transferred membrane with 4% paraformaldehyde and 0.01 ~ 0.1% glutaraldehyde produced an approximately 10-fold increase in the sensitivity for Ser129-phosphorylated α-synuclein monomers, allowing detection of endogenous proteins even in conditioned medium, human cerebrospinal fluid, and extracts from cell lines and human brain. This method may enable more detailed biochemical analyses for α-synuclein transmission between intra and extracellular spaces under physiological and pathological conditions.


Assuntos
Western Blotting , Serina/metabolismo , alfa-Sinucleína/metabolismo , Animais , Western Blotting/métodos , Encéfalo/metabolismo , Linhagem Celular Tumoral , Códon , Espaço Extracelular/metabolismo , Humanos , Espaço Intracelular/metabolismo , Fosforilação , Ratos , Sensibilidade e Especificidade , Serina/química , alfa-Sinucleína/química
19.
Gan To Kagaku Ryoho ; 42(13): 2461-6, 2015 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-26809305

RESUMO

This study investigated the relationship between quality of life (QOL) and efficacy or occurrence of adverse events in patients who were administered lenalidomide and dexamethasone (Len+Dex) therapy for relapsed or refractory multiple myeloma (MM) in the hematology department at Obihiro Kosei Hospital from September 2010 to September 2012. QOL was evaluated using a quality of life questionnaire for cancer patients treated with anticancer drugs (QOL-ACD). The average QOL score of 7 patients receiving 4 cycles of Len+Dex treatment decreased 5 points from baseline Len+Dex treatment. The change in QOL score was significantly correlated with changes in serum M-protein (correlation coefficient: R=0.777). However, there was no significant correlation between adverse events and the change in QOL score. Our results indicate that QOL may be improved by the effects of Len+Dex treatment.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Mieloma Múltiplo/tratamento farmacológico , Qualidade de Vida , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Dexametasona/administração & dosagem , Dexametasona/efeitos adversos , Feminino , Humanos , Lenalidomida , Pessoa de Meia-Idade , Inquéritos e Questionários , Talidomida/administração & dosagem , Talidomida/efeitos adversos , Talidomida/análogos & derivados
20.
Cell Metab ; 20(1): 119-32, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24910243

RESUMO

Metabolic disorders, including obesity and insulin resistance, have their basis in dysregulated lipid metabolism and low-grade inflammation. In a microarray search of unique lipase-related genes whose expressions are associated with obesity, we found that two secreted phospholipase A2s (sPLA2s), PLA2G5 and PLA2G2E, were robustly induced in adipocytes of obese mice. Analyses of Pla2g5(-/-) and Pla2g2e(-/-) mice revealed distinct roles of these sPLA2s in diet-induced obesity. PLA2G5 hydrolyzed phosphatidylcholine in fat-overladen low-density lipoprotein to release unsaturated fatty acids, which prevented palmitate-induced M1 macrophage polarization. As such, PLA2G5 tipped the immune balance toward an M2 state, thereby counteracting adipose tissue inflammation, insulin resistance, hyperlipidemia, and obesity. PLA2G2E altered minor lipoprotein phospholipids, phosphatidylserine and phosphatidylethanolamine, and moderately facilitated lipid accumulation in adipose tissue and liver. Collectively, the identification of "metabolic sPLA2s" adds this gene family to a growing list of lipolytic enzymes that act as metabolic coordinators.


Assuntos
Tecido Adiposo Branco/metabolismo , Fosfolipases A2 do Grupo II/metabolismo , Fosfolipases A2 do Grupo V/metabolismo , Obesidade/etiologia , Tecido Adiposo Branco/citologia , Animais , Células Cultivadas , Dieta Hiperlipídica , Feminino , Teste de Tolerância a Glucose , Fosfolipases A2 do Grupo II/deficiência , Fosfolipases A2 do Grupo II/genética , Fosfolipases A2 do Grupo V/deficiência , Fosfolipases A2 do Grupo V/genética , Humanos , Inflamação/metabolismo , Inflamação/patologia , Insulina/sangue , Leptina/sangue , Leptina/metabolismo , Lipoproteínas/metabolismo , Fígado/patologia , Macrófagos/citologia , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Obesos , Obesidade/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/metabolismo , Fatores de Tempo
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