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1.
Dev Growth Differ ; 64(9): 494-500, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36308507

RESUMO

Urodele amphibians have exceptional regeneration ability in various organs. Among these, the Iberian ribbed newt (Pleurodeles waltl) has emerged as a useful model organism for investigating the mechanisms underlying regeneration. Neural stem cells (NSCs) are an important source of regeneration in the central nervous system (CNS) and their culture method in vitro has been well established. NSCs form spherical cell aggregates called neurospheres and their formation has been demonstrated in various vertebrates, including some urodele species, but not in P. waltl. In this study, we reported neurosphere formation in brain- and spinal cord-derived cells of post-metamorphic P. waltl. These neurospheres showed proliferative activity and similar expression of marker proteins. However, the surface morphology was found to vary according to their origin, implying that the characteristics of the neurospheres generated from the brain and spinal cord could be similar but not identical. Subsequent in vitro differentiation analysis demonstrated that spinal cord-derived neurospheres gave rise to neurons and glial cells. We also found that cells in neurospheres from P. waltl differentiated to oligodendrocytes, whereas those from axolotls were reported not to differentiate to this cell type under standard culture conditions. Based on our findings, implantation of genetically modified neurospheres together with associated technical advantages in P. waltl could reveal pivotal gene(s) and/or signaling pathway(s) essential for the complete spinal cord regeneration ability in the future.


Assuntos
Células-Tronco Neurais , Pleurodeles , Animais , Pleurodeles/anatomia & histologia , Pleurodeles/metabolismo , Salamandridae , Medula Espinal , Neurônios
2.
J Lipid Res ; 63(6): 100210, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35439525

RESUMO

Diverse molecular species of sulfatide with differences in FA lengths, unsaturation degrees, and hydroxylation statuses are expressed in the kidneys. However, the physiological functions of specific sulfatide species in the kidneys are unclear. Here, we evaluated the distribution of specific sulfatide species in the kidneys and their physiological functions. Electron microscopic analysis of kidneys of Cst-deficient mice lacking sulfatide showed vacuolar accumulation in the cytoplasm of intercalated cells in the collecting duct, whereas the proximal and distal tubules were unchanged. Immunohistochemical analysis revealed that vacuolar H+-ATPase-positive vesicles were accumulated in intercalated cells in sulfatide-deficient kidneys. Seventeen sulfatide species were detected in the murine kidney by iMScope MALDI-MS analysis. The distribution of the specific sulfatide species was classified into four patterns. Although most sulfatide species were highly expressed in the outer medullary layer, two unique sulfatide species of m/z 896.6 (predicted ceramide structure: t18:0-C22:0h) and m/z 924.6 (predicted ceramide structure: t18:0-C24:0h) were dispersed along the collecting duct, implying expression in intercalated cells. In addition, the intercalated cell-enriched fraction was purified by fluorescence-activated cell sorting using the anti-vacuolar H+-ATPase subunit 6V0A4, which predominantly contained sulfatide species (m/z 896.6 and 924.6). The Degs2 and Fa2h genes, which are responsible for ceramide hydroxylation, were expressed in the purified intercalated cells. These results suggested that sulfatide molecular species with ceramide composed of phytosphingosine (t18:0) and 2-hydroxy FAs, which were characteristically expressed in intercalated cells, were involved in the excretion of NH3 and protons into the urine.


Assuntos
Sulfoglicoesfingolipídeos , ATPases Vacuolares Próton-Translocadoras , Animais , Ceramidas , Rim/metabolismo , Camundongos , Esfingosina/análogos & derivados , ATPases Vacuolares Próton-Translocadoras/metabolismo
3.
Cell Tissue Res ; 386(3): 477-490, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34562148

RESUMO

Lamellar corpuscles function as mechanoreceptors in the skin, composed of axon terminals and lamellae constructed by terminal Schwann cells. They are classified into Pacinian, Meissner, and simple corpuscles based on histological criteria. Lamellar corpuscles in rat dermal papilla cells have been reported; however, the morphological aspects have yet to be thoroughly investigated. In the present study, we analyzed the enzyme activity, distribution, fine structure, and three-dimensional innervation of lamellar corpuscles in rat plantar skin. The lamellar corpuscles exhibiting non-specific cholinesterase were densely distributed in rat footpads, evident as notable skin elevations, especially at the apex, the highest portion of the ridges in each footpad. In contrast, only a few lamellar corpuscles were found in other plantar skin areas. Lamellar corpuscle was considered composed of a flat axon terminal Schwann cell lamellae, which were roughly concentrically arranged in the dermal papilla. These histological characteristics correspond to those of the simple corpuscle. Moreover, the axon tracing method revealed that one trunk axon innervated several simple corpuscles. The territory of the trunk axons overlapped with each other. Finally, the animals' footprints were analyzed. During the pausing and walking phases, footpads are often in contact with the floor. These results demonstrate that the type of lamellar corpuscles in the dermal papillae of rat plantar skin is a simple corpuscle and implies that their distribution pattern in the plantar skin is convenient for efficient sensing and transmission of mechanical stimuli from the ground.


Assuntos
Pé/fisiologia , Células Receptoras Sensoriais/fisiologia , Pele/anatomia & histologia , Pele/inervação , Animais , Ratos , Ratos Wistar
4.
Biol Pharm Bull ; 44(7): 910-919, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33896885

RESUMO

Glioblastoma multiforme (GBM) is the most prevalent malignant primary brain tumor with a high recurrence rate. Despite multimodal therapy including surgical resection, chemotherapy, and radiotherapy, the median survival time after the initial diagnosis of GBM is approximately 14 months. Since cancer stem cells (CSCs) are considered the leading cause of cancer recurrence, glioblastoma stem cell-targeted therapy is a promising strategy for the treatment of GBM. However, because CSC heterogeneity has been implicated in the difficulties of CSC-target therapy, more in-depth knowledge of CSC biology is still required to develop novel therapies. In this study, we established single cell-derived tumorspheres from human glioblastoma U87MG cells. One of these tumorspheres, P4E8 clone, showed CSC-like phenotypes, such as self-renewal capacity, expression of CSC markers, resistance to anti-cancer agents, and in vivo tumorigenicity. Therefore, we used P4E8 cells as a cell-based model of glioblastoma stem cells (GSCs). Gene expression analysis using microarray indicated that the most highly expressed genes in P4E8 cells compared to the parental U87MG were PC3-secreted microprotein (MSMP). Furthermore, MSMP was expressed in patient-derived GSCs and human glioma tissues at the protein level, implying that MSMP might contribute to glioma development and progression.


Assuntos
Glioma/fisiopatologia , Proteínas de Neoplasias/metabolismo , Células-Tronco Neoplásicas/metabolismo , Animais , Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Expressão Gênica , Glioblastoma/fisiopatologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Recidiva Local de Neoplasia/tratamento farmacológico , Células-Tronco Neoplásicas/efeitos dos fármacos , Transplante Heterólogo
5.
iScience ; 23(6): 101248, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32629613

RESUMO

Elucidating fine architectures and functions of cellular and synaptic connections requires development of new flexible methods. Here, we created a concept called the "battle of transgenes," based on which we generated strategies using genetically engineered battles of multiple recombinases. The strategies enabled split-tunable allocation of multiple transgenes. We demonstrated the versatility of these strategies and technologies in inducing strong and multi-sparse allocations of multiple transgenes. Furthermore, the combination of our transgenic strategy and expansion microscopy enabled three-dimensional high-resolution imaging of whole synaptic structures in the hippocampus with simultaneous visualizations of endogenous synaptic proteins. These strategies and technologies based on the battle of genes may accelerate the analysis of whole synaptic and cellular connections in diverse life science fields.

6.
J Neuroimmunol ; 331: 74-86, 2019 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29107327

RESUMO

Microglia are the primary resident immune cells of the brain parenchyma and transform into the amoeboid form in the "activated state" under pathological conditions from the ramified form in the "resting state" under physiologically healthy conditions. In the present study, we found that microglia in the circumventricular organs (CVOs) of adult mice displayed the amoeboid form with fewer branched cellular processes even under normal conditions; however, those in other brain regions showed the ramified form, which is characterized by well-branched and dendritic cellular processes. Moreover, microglia in the CVOs showed the strong protein expression of the M1 markers CD16/32 and CD86 and M2 markers CD206 and Ym1 without any pathological stimulation. Thus, the present results indicate that microglia in the CVOs of adult mice are morphologically and functionally activated under normal conditions, possibly due to the specialized features of the CVOs, namely, the entry of blood-derived molecules into parenchyma through fenestrated capillaries and the presence of neural stem cells.


Assuntos
Órgãos Circunventriculares/citologia , Microglia/fisiologia , Animais , Antígenos CD/biossíntese , Antígenos CD/genética , Capilares/fisiologia , Permeabilidade Capilar , Forma Celular , Órgãos Circunventriculares/irrigação sanguínea , Regulação da Expressão Gênica , Lectinas/fisiologia , Lectinas Tipo C/fisiologia , Macrófagos/fisiologia , Masculino , Receptor de Manose , Lectinas de Ligação a Manose/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Microglia/citologia , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Nestina/deficiência , Células-Tronco Neurais/citologia , Receptores de Superfície Celular/fisiologia , beta-N-Acetil-Hexosaminidases/fisiologia
7.
J Neuroimmunol ; 331: 58-73, 2019 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29752068

RESUMO

Toll-like receptor 4 (TLR4) recognizes bacteria-derived lipopolysaccharide (LPS). In the present study, we found that intraperitoneal LPS activated nuclear factor-κ B (NF-κB) in TLR4-expressing neural stem cells (NSCs) in the circumventricular brain regions of mice. Intracerebroventricular preadministration of low-dose TLR4 inhibitors significantly augmented hyperthermia together with the inhibition of NF-κB activation in circumventricular NSCs of LPS-inflamed animals. Moreover, intracerebroventricular administration of high-dose TLR4 inhibitors induced hyperthermia and Fos activation in circumventricular NSCs and hypothalamic neurons. These results suggest that TLR4 on circumventricular NSCs functions as a central regulator for thermogenesis under inflamed and normal conditions.


Assuntos
Encéfalo/fisiologia , Órgãos Circunventriculares/fisiologia , Células-Tronco Neurais/efeitos dos fármacos , Termogênese/fisiologia , Receptor 4 Toll-Like/fisiologia , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Encéfalo/efeitos dos fármacos , Órgãos Circunventriculares/citologia , Órgãos Circunventriculares/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Febre/induzido quimicamente , Febre/fisiopatologia , Injeções Intraventriculares , Lipopolissacarídeos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos ICR , Microglia/efeitos dos fármacos , Microglia/metabolismo , NF-kappa B/metabolismo , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Células-Tronco Neurais/fisiologia , Peptídeos/farmacologia , Proteínas Proto-Oncogênicas c-fos/biossíntese , Proteínas Proto-Oncogênicas c-fos/genética , Termogênese/efeitos dos fármacos , Receptor 4 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/biossíntese
8.
J Neuroimmunol ; 278: 144-58, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25595264

RESUMO

The sensory circumventricular organs (CVOs) comprise the organum vasculosum of the lamina terminalis (OVLT), subfornical organ (SFO), and area postrema (AP) and lack the blood-brain barrier. The expression of Toll-like receptor 4 (TLR4) was seen at astrocytes throughout the sensory CVOs and at microglia in the AP and solitary nucleus around the central canal. The peripheral and central administration of lipopolysaccharide induced a similar pattern of nuclear translocation of STAT3. A microglia inhibitor minocycline largely suppressed lipopolysaccharide-induced astrocytic nuclear translocation of STAT3 in the OVLT and AP, but its effect was less in the SFO.


Assuntos
Encéfalo/anatomia & histologia , Órgãos Circunventriculares/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Fator de Transcrição STAT3/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Encéfalo/efeitos dos fármacos , Proteínas de Ligação ao Cálcio/metabolismo , Relação Dose-Resposta a Droga , Vias de Administração de Medicamentos , Proteína Glial Fibrilar Ácida/metabolismo , Laminina/metabolismo , Antígenos Comuns de Leucócito/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Proteínas dos Microfilamentos/metabolismo , Microscopia Confocal , Minociclina/farmacologia , Fatores de Tempo
9.
Int Heart J ; 47(5): 651-61, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17106136

RESUMO

We estimated the benefit of a sirolimus-eluting stent (SES, Cypher) for diffuse (> 10 mm) in-stent restenosis (ISR) inside bare metal stents (BMS) because the feasibility of the SES was not confirmed after its recent approval in Japan. Clinical and angiographic outcomes after SES implantation to 93 diffuse ISR were compared with those of 3 groups treated by plain old balloon angioplasty (POBA, (n = 54)), cutting balloon angioplasty (CB, (n = 24)), and BMS (n = 41) in a series of 153 patients whose follow-up quantitative coronary angiography (QCA) evaluated 3-9 months after the treatments was obtained from January 2003 through December 2005. For 33 lesions in the SES group, 12-month follow-up QCA results were obtained and compared with those at 6 months. Ticlopidine (200 mg/day) was prescribed for at least 12 weeks after SES implantation and for 2 weeks after BMS in addition to aspirin (81-100 mg/day). Patient characteristics and the characteristics of previous implanted BMS in the SES group were not significantly different from those in the other groups. Death from cardiac causes and nonfatal myocardial infarction did not occur in any group. Stent thrombosis was not observed in the BMS and SES groups. The incidence of repeat target lesion revascularization (re-TLR) in the SES group (3.23%) was significantly lower compared with that of the POBA (37.0%), CB (25.0%), and BMS (29.3%) groups (P < 0.001, respectively). Late loss in the SES group (0.44 +/- 0.41 mm) was significantly smaller than that in the BMS group (1.34 +/- 0.74 mm) (P < 0.05). The rate of recurrent ISR (re-ISR) in SES (5.38%) was significantly lower than that in POBA (46.3%), CB (41.7%), and BMS (46.3%) (P < 0.001, respectively). The QCA variables at 6 months in the SES group were not significantly different from those at 12 months. Thus, SES implantation for diffuse ISR was far superior since it markedly reduced the incidence of re-TLR with re-ISR at up to 6-months follow-up. In addition, this angiographic patency after SES implantation continued until 12 months.


Assuntos
Reestenose Coronária/terapia , Sirolimo/administração & dosagem , Stents , Angioplastia Coronária com Balão , Angiografia Coronária , Fibrinolíticos/uso terapêutico , Seguimentos , Humanos , Metais , Inibidores da Agregação Plaquetária/uso terapêutico , Desenho de Prótese , Ticlopidina/uso terapêutico
10.
Circ J ; 70(8): 1091-2, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16864948

RESUMO

BACKGROUND: The incidence of subacute stent thrombosis (SAT) within 30 days after stenting with a sirolimus-eluting stent (Cypher) for acute myocardial infarction (AMI) was retrospectively compared to that with bare-metal stents (BMS). METHODS AND RESULTS: Among 559 lesions in 558 consecutive AMI from April 2003 to February 2006, the incidence of documented SAT after Cypher implantation (2/276 lesions, 0.72%) was almost the same as for BMS (2 cases, 0.71%). Aspirin (81-100 mg/day) plus ticlopidine (200 mg/day) were administered continuously after admission in all 4 cases. CONCLUSION: Documented SAT did not increase after stenting with Cypher for AMI under aspirin plus ticlopidine.


Assuntos
Trombose Coronária/epidemiologia , Trombose Coronária/etiologia , Infarto do Miocárdio/cirurgia , Stents/efeitos adversos , Idoso , Aspirina/uso terapêutico , Reestenose Coronária/complicações , Trombose Coronária/prevenção & controle , Progressão da Doença , Feminino , Humanos , Imunossupressores/administração & dosagem , Incidência , Masculino , Inibidores da Agregação Plaquetária/uso terapêutico , Estudos Retrospectivos , Sirolimo/administração & dosagem , Ticlopidina/uso terapêutico , Fatores de Tempo
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