RESUMO
Yaks are typical plateau-adapted animals, however the microvascular changes and characteristics in their lungs after birth are still unclear. Pulmonary microvasculature characteristics and changes across age groups were analysed using morphological observation and molecular biology detection in yaks aged 1, 30 and 180 days old in addition to adults. Results: Our experiments demonstrated that yaks have fully developed pulmonary alveolar at birth but that interalveolar thickness increased with age. Immunofluorescence observations showed that microvessel density within the interalveolar septum in the yak gradually increased with age. In addition, transmission electron microscopy (TEM) results showed that the blood-air barrier of 1-day old and 30-days old yaks was significantly thicker than that observed at 180-days old and in adults (P < 0.05), which was caused by the thinning of the membrane of alveolar epithelial cells. Furthermore, Vegfa and Epas1 expression levels in 30-day old yaks were the highest in comparison to the other age groups (P < 0.05), whilst levels in adult yaks were the lowest (P < 0.05). The gradual increase in lung microvessel density can effectively satisfy the oxygen requirements of ageing yaks. In addition, these results suggest that the key period of yak lung development is from 30 to 180 days.
Assuntos
Bovinos/anatomia & histologia , Pulmão/irrigação sanguínea , Animais , Animais Recém-Nascidos/anatomia & histologia , Animais Recém-Nascidos/crescimento & desenvolvimento , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Western Blotting , Bovinos/crescimento & desenvolvimento , Pulmão/anatomia & histologia , Pulmão/crescimento & desenvolvimento , Pulmão/ultraestrutura , Microcirculação , Microscopia Eletrônica de Transmissão , Densidade Microvascular , Microvasos/anatomia & histologia , Microvasos/ultraestrutura , Alvéolos Pulmonares/anatomia & histologia , Alvéolos Pulmonares/irrigação sanguínea , Alvéolos Pulmonares/ultraestrutura , Reação em Cadeia da Polimerase em Tempo Real , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Mannitol, a representative of hyperosmolar therapy, is indispensable for the treatment of malignant cerebral infarction, but its therapeutic effect is limited by its exacerbation of blood-brain barrier (BBB) disruption. This study was to explore whether Danhong injection (DHI), a standardized product extracted from Salvia miltiorrhiza Bunge and Carthamus tinctorius L., inhibits the destructive effect of mannitol on BBB and thus enhancing the treatment of hemispheric ischemic stroke. SD rats were subjected to pMCAO followed by intravenous bolus injections of mannitol with/without DHI intervention. Neurological deficit score, brain edema, infarct volume at 24 h after MCAO and histopathology, microvascular ultrastructure, immunohistochemistry and immunofluorescence staining of endothelial cell junctions, energy metabolism in the ischemic penumbra were assessed. Intravenous mannitol after MCAO resulted in a decrease in 24 h mortality and cerebral edema, whereas no significant benefit on neurological deficits, infarct volume and microvascular ultrastructure. Moreover, mannitol led to the loss of endothelial integrity, manifested by the decreased expression of occludin, junctional adhesion molecule-1 (JAM-1) and zonula occluden-1 (ZO-1) and the discontinuity of occludin staining around the periphery of endothelial cells. Meanwhile, after mannitol treatment, energy-dependent vimentin and F-actin, ATP content, and ATP5D expression were down-regulated, while MMP2 and MMP9 expression increased in the ischemic penumbra. All the insults after mannitol treatment were attenuated by addition of intravenous DHI. The results suggest DHI as a potential remedy to attenuate mannitol-related BBB disruption, and the potential of DHI to upregulate energy metabolism and inhibit the activity of MMPs is likely attributable to its effects observed.
Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Isquemia Encefálica/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , AVC Isquêmico/tratamento farmacológico , Manitol/farmacologia , Fármacos Neuroprotetores/farmacologia , Animais , Edema Encefálico/tratamento farmacológico , Isquemia Encefálica/patologia , Citoesqueleto/efeitos dos fármacos , Modelos Animais de Doenças , Quimioterapia Combinada/métodos , Medicamentos de Ervas Chinesas/administração & dosagem , Células Endoteliais/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/patologia , Injeções , Junções Intercelulares/efeitos dos fármacos , AVC Isquêmico/patologia , Manitol/uso terapêutico , Metaloproteinases da Matriz/efeitos dos fármacos , Microvasos/efeitos dos fármacos , Microvasos/ultraestrutura , Doenças do Sistema Nervoso/tratamento farmacológico , Fármacos Neuroprotetores/administração & dosagem , Ratos Sprague-Dawley , Taxa de SobrevidaRESUMO
BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most vascularized tumor types, and is characterized by development of heterogeneous immature vessels with increased permeability. Here, we analyzed morphology and vascular permeability-related structures in endothelial cells of HCC microvessels. METHODS: Small (Type I) and large (Type II) peritumoral blood microvessels were assessed in HCC-bearing mice. By transmission electron microscopy, endothelial cell cytoplasm area, free transport vesicles, vesiculo-vacuolar organelles and clathrin-coated vesicles were measured. RESULTS: The phenotypic changes in the HCC microvessels included presence of sinusoidal capillarization, numerous luminal microprocesses and abnormal luminal channels, irregular dilatations of interendothelial junctions, local detachment of basement membranes and widened extracellular space. Endothelial cells Type I microvessels showed increased vesicular trafficking-related structures. CONCLUSION: Ultrastructural characteristics of microvessels Type I can associate with HCC new-formed microvessels. The morphological changes observed in HCC microvessels might explain the increased transcellular and paracellular permeability in HCC endothelial cells.
Assuntos
Carcinoma Hepatocelular/irrigação sanguínea , Células Endoteliais/ultraestrutura , Neoplasias Hepáticas/irrigação sanguínea , Microvasos/ultraestrutura , Vesículas Transportadoras/ultraestrutura , Animais , Transporte Biológico , Permeabilidade Capilar , Linhagem Celular Tumoral , Células Endoteliais/metabolismo , Masculino , Camundongos Endogâmicos CBA , Microscopia Eletrônica de Transmissão , Microvasos/metabolismo , Vesículas Transportadoras/metabolismoRESUMO
The vascular and perivascular cells, including telocytes (TCs) and immune cells, play an important role in male fertility. The current study intended to describe in detail the microvascular structures harboring special regulatory devices in addition to the interstitial cellular components of the one-humped camel epididymis. The samples were collected from 10 clinically healthy mature camels (Camelus dromedarius). The distribution and characteristics of TCs, peripheral blood vessels of the epididymis, and immune cells were investigated using the light, immunohistochemistry, immunofluorescence, and transmission electron microscopy analyses. Frequent occlusive or throttle arterioles were demonstrated in the epididymal interstitium and their tunica media consisted of glomus cells. In addition, some vein walls consisted of one or two layers of glomus cells. TCs, fibroblasts, muscle cells, and tunica media of the blood vessels, that present in the loose connective tissue surrounding the intertubular interstitium of camel epididymis, showed a positive reaction with vimentin. The endothelium of blood vessels and veins showed positive immunoreactivity for CD34 and vascular endothelial growth factor (VEGF). Furthermore, VEGF, CD34, and S100 proteins were expressed in dendritic cells (DCs) as well as TCs. The current data suggest the involvement of DCs and TCs in angiogenesis and a possible role for the interstitial components in creating an appropriate milieu for the full maturation of sperms.
Assuntos
Camelus , Epididimo/patologia , Epididimo/ultraestrutura , Microvasos/patologia , Microvasos/ultraestrutura , Telócitos/patologia , Telócitos/ultraestrutura , Animais , Antígenos CD34 , Arteríolas/ultraestrutura , Vasos Sanguíneos/ultraestrutura , Camelus/metabolismo , Tecido Conjuntivo/ultraestrutura , Epididimo/metabolismo , Fibroblastos , Imunofluorescência/métodos , Imuno-Histoquímica/métodos , Masculino , Microscopia Eletrônica de Transmissão/métodos , Microvasos/metabolismo , Telócitos/metabolismo , Fator A de Crescimento do Endotélio VascularRESUMO
Susac syndrome is a rare, immune-mediated disease characterized by encephalopathy, branch retinal artery occlusion, and hearing loss. Herein, we describe the electron microscopic findings of three brain biopsies and two brain autopsies performed on five patients whose working clinical diagnosis was Susac syndrome. In all five cases, the key findings were basement membrane thickening and collagen deposition in the perivascular space involving small vessels and leading to thickening of vessel walls, narrowing, and vascular occlusion. These findings indicate that Susac syndrome is a microvascular disease. Mononuclear cells were present in the perivascular space, underlining the inflammatory nature of the pathology. Though nonspecific, the changes can be distinguished from genetic and acquired small vessel diseases. The encephalopathy of Susac syndrome overlaps clinically with degenerative and infectious conditions, and brain biopsy may be used for its diagnosis. Its vascular etiology may not be obvious on light microscopy, and electron microscopy is important for its confirmation.
Assuntos
Encéfalo/patologia , Encéfalo/ultraestrutura , Microvasos/patologia , Microvasos/ultraestrutura , Síndrome de Susac/patologia , Feminino , Humanos , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Adulto JovemRESUMO
RATIONALE AND OBJECTIVES: This study aimed to test the hypothesis that ultrastructural wall abnormalities of lymphoma vessels correlate with perfusion computed tomography (PCT) kinetics. MATERIALS AND METHODS: Our local institutional review board approved this prospective study. Between February 2013 and June 2016, we included 23 consecutive subjects with newly diagnosed lymphoma, who were referred for computed tomography-guided biopsy (6 women, 17 men; mean age, 60.61 ± 12.43 years; range, 28-74 years) and additionally agreed to undergo PCT of the target lymphoma tissues. PCT was obtained for 40 seconds using 80 kV, 120 mAs, 64 × 0.6-mm collimation, 6.9-cm z-axis coverage, and 26 volume measurements. Mean and maximum k-trans (mL/100 mL/min), blood flow (BF; mL/100 mL/min) and blood volume (BV) were quantified using the deconvolution and the maximum slope + Patlak calculation models. Immunohistochemical staining was performed for microvessel density quantification (vessels/m2), and electron microscopy was used to determine the presence or absence of tight junctions, endothelial fenestration, basement membrane, and pericytes, and to measure extracellular matrix thickness. RESULTS: Extracellular matrix thickness as well as the presence or absence of tight junctions, basal lamina, and pericytes did not correlate with computed tomography perfusion parameters. Endothelial fenestrations correlated significantly with mean BFdeconvolution (P = .047, r = 0.418) and additionally was significantly associated with higher mean BVdeconvolution (P < .005). Mean k-transPatlak correlated strongly with mean k-transdeconvolution (r = 0.939, P = .001), and both correlated with mean BFdeconvolution (P = .001, r = 0.748), max BFdeconvolution (P = .028, r = 0.564), mean BVdeconvolution (P = .001, r = 0.752), and max BVdeconvolution (P = .001, r = 0.771). Microvessel density correlated with max k-transdeconvolution (r = 0.564, P = .023). Vascular endothelial growth factor receptor-3 expression (receptor specific for lymphatics) correlated significantly with max k-transPatlak (P = .041, r = 0.686) and mean BFdeconvolution (P = .038, r = 0.695). CONCLUSION: k-Trans values of PCT do not correlate with ultrastructural microvessel features, whereas endothelial fenestrations correlate with increased intra-tumoral BVs.
Assuntos
Linfoma , Microvasos/ultraestrutura , Imagem de Perfusão/métodos , Tomografia Computadorizada por Raios X/métodos , Idoso , Correlação de Dados , Feminino , Humanos , Imuno-Histoquímica , Linfoma/metabolismo , Linfoma/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias/irrigação sanguínea , Estudos ProspectivosRESUMO
AIMS: Familial hemiplegic migraine type 1 (FHM1) due to mutations in the CACNA1A gene is known as functional vascular disorder with cerebellar atrophy. We describe a case of a FHM1 family in which pathological changes occurred in both brain neuroimaging and skin and muscle biopsy. MATERIALS AND METHODS: In 5 of 18 affected family members, brain MRI scans revealed hyperintense changes in the cerebral white matter. In 2 of these 5 patients, skin and muscle biopsies were performed at the interictal period of the disease and examined under light and transmission electron microscopy. RESULTS: Ultrastructural examination of the biopsy samples revealed abnormal appearance of microvessels resembling oncosis. In the affected vessels, endothelial cells and myocytes/pericytes showed clear cytoplasm, distended endoplasmic reticulum, enlarged mitochondria, and numerous intracytoplasmic vesicular structures. Swollen endothelial cells often significantly narrowed vessel lumen. CONCLUSION: The morphological changes described for the first time in FHM1 suggest that the disease may not only be a functional, but also a structural vascular disorder. We suggest that the presence of these vascular abnormalities can interfere with microcirculation causing damage to the cerebral white matter, visible in MRI scans as hyperintense changes.â©.
Assuntos
Ataxia Cerebelar/patologia , Microvasos/patologia , Microvasos/ultraestrutura , Transtornos de Enxaqueca/patologia , Adolescente , Adulto , Encéfalo/patologia , Encéfalo/ultraestrutura , Canais de Cálcio/genética , Ataxia Cerebelar/genética , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos de Enxaqueca/genética , Músculo Esquelético/patologia , Músculo Esquelético/ultraestrutura , Mutação , Linhagem , Pele/patologia , Pele/ultraestrutura , Adulto JovemRESUMO
PURPOSE: The aim of this study is to investigate the effects of fenofibrate (FA) on microvascular dysfunction in the retina of diabetic rats, and to determine the underlying mechanism. METHODS: Streptozotocin (STZ)-induced diabetic rats and control rats were used in this study. A subgroup of STZ-induced diabetic rats was treated orally with vehicle or FA (100 mg/kg/day) for 24 weeks along with regular monitoring of body weight and serum parameters. At the end of the 24-week treatment, retinal vascular permeability was quantified by confocal microscopy using Evans blue as a tracer. Retinal capillary basement membrane thickness (BMT) was examined by transmission electron microscopy. The retinal reactive oxygen species (ROS) level was quantified by flow cytometry using a fluorescent probe. Levels of vascular endothelial growth factor (VEGF), nuclear facto (NF)-κB (p65), and thioredoxin interacting protein (TXNIP) were measured by Western blotting or enzyme-linked immunosorbent assay and real-time reverse transcription polymerase chain reaction. RESULTS: Retinal vascular permeability and BMT were significantly increased in diabetic rats compared to in non-diabetic control rats. Diabetes also increased the retinal ROS levels. These effects were associated with increased levels of VEGF, phosphorylation of p65(P-p65), and TXNIP. FA significantly ameliorated the retinal vascular permeability, alleviated retinal BMT, and reduced retinal ROS level. Consistent with these effects, FA also decreased VEGF and P-p65 expression and, at the same time, decreased TXNIP expression. CONCLUSIONS: FA prevents the retinal microvascular dysfunction induced by diabetes, likely by restoring VEGF and P-p65 levels, and possibly by reducing oxidative stress and TXNIP expression.
Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Retinopatia Diabética/tratamento farmacológico , Fenofibrato/farmacologia , Microcirculação/fisiologia , Microvasos/fisiopatologia , Estresse Oxidativo/efeitos dos fármacos , Vasos Retinianos/fisiopatologia , Animais , Proteínas de Transporte/metabolismo , Proteínas de Ciclo Celular , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Retinopatia Diabética/etiologia , Retinopatia Diabética/metabolismo , Hipolipemiantes/farmacologia , Masculino , Microcirculação/efeitos dos fármacos , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Microvasos/efeitos dos fármacos , Microvasos/ultraestrutura , Ratos , Ratos Sprague-Dawley , Vasos Retinianos/efeitos dos fármacos , Fator de Transcrição RelA/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
OBJECTIVE: Adipose tissue (AT) dysfunction associated with obesity or aging is a major cause for lipid redistribution and the progression of cardiometabolic disorders. Our goal is to decipher the contribution of human AT microvascular endothelial cells (ECs) in the maintenance of fatty acid (FA) fluxes and the impact of senescence on their function. APPROACH AND RESULTS: We used freshly isolated primary microvascular ECs from human AT. Our data identified the endothelial FA handling machinery including FATPs (FA transport proteins) FATP1, FATP3, FATP4, and CD36 as well as FABP4 (FA binding protein 4). We showed that PPARγ (peroxisome proliferator-activated receptor gamma) regulates the expression of FATP1, CD36, and FABP4 and is a major regulator of FA uptake in human AT EC (hATEC). We provided evidence that endothelial PPARγ activity is modulated by senescence. Indeed, the positive regulation of FA transport by PPARγ agonist was abolished, whereas the emergence of an inflammatory response was favored in senescent hATEC. This was associated with the retention of nuclear FOXO1 (forkhead box protein O1), whereas nuclear PPARγ translocation was impaired. CONCLUSIONS: These data support the notion that PPARγ is a key regulator of primary hATEC function including FA handling and inflammatory response. However, the outcome of PPARγ activation is modulated by senescence, a phenomenon that may impact the ability of hATEC to properly respond to and handle lipid fluxes. Finally, our work highlights the role of hATEC in the regulation of FA fluxes and reveals that dysfunction of these cells with accelerated aging is likely to participate to AT dysfunction and the redistribution of lipids.
Assuntos
Gordura Abdominal/irrigação sanguínea , Senescência Celular , Células Endoteliais/metabolismo , Ácidos Graxos/metabolismo , Inflamação/metabolismo , Microvasos/metabolismo , PPAR gama/metabolismo , Transporte Ativo do Núcleo Celular , Proliferação de Células , Células Cultivadas , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Células Endoteliais/ultraestrutura , Proteínas de Ligação a Ácido Graxo/genética , Proteínas de Ligação a Ácido Graxo/metabolismo , Feminino , Proteína Forkhead Box O1/metabolismo , Humanos , Inflamação/genética , Inflamação/patologia , Microvasos/ultraestrutura , PPAR gama/genética , Transdução de SinaisRESUMO
PURPOSE: Pulmonary microvascular injury is associated with the pathogenesis of bronchopulmonary dysplasia (BPD). To characterize the mechanisms of pulmonary vascular disease resulting from BPD, we studied the ultrastructural changes affecting pulmonary microvasculature. METHODS: Newborn ICR mice were exposed to 85% hyperoxia or normoxia for 14 days, and then normal air replacement conditions for the following 7 days. At postnatal day (P)14 and P21, lungs were harvested for ultrastructural examination and assessment of pulmonary hypertension. RESULTS: The ultrastructure of pulmonary microvasculature in the hyperoxia-exposed lungs revealed a collapsed capillary lumen. This was due to the abnormal morphology of endothelial cells (ECs) characterized by heterogeneously thick cytoplasm. Compared to normal air controls, the specimens displayed also remarkably thick blood-air barriers (BABs), most of which were occupied by EC layer components. Structural changes were accompanied by increased pulmonary artery medial thickness and right ventricular hypertrophy (RVH). Moreover, abnormalities in ECs persisted even after exposure to 7 days of normal air replacement conditions. Results were confirmed by morphometric quantification. CONCLUSION: Our results suggest that the abnormal morphology of capillary ECs and thick BABs correlates with pulmonary artery remodeling and RVH. These ultrastructural changes might represent possible mechanisms of secondary pulmonary hypertension in BPD.
Assuntos
Displasia Broncopulmonar/patologia , Hiperóxia/complicações , Hipertensão Pulmonar/patologia , Microvasos/ultraestrutura , Animais , Animais Recém-Nascidos , Displasia Broncopulmonar/etiologia , Modelos Animais de Doenças , Células Endoteliais/patologia , Endotélio Vascular/citologia , Endotélio Vascular/patologia , Endotélio Vascular/ultraestrutura , Feminino , Humanos , Hipertensão Pulmonar/etiologia , Hipertrofia Ventricular Direita/patologia , Pulmão/irrigação sanguínea , Pulmão/patologia , Pulmão/ultraestrutura , Camundongos , Camundongos Endogâmicos ICR , Microscopia Eletrônica de Transmissão , Microvasos/citologia , Microvasos/patologia , Artéria Pulmonar/patologia , Artéria Pulmonar/ultraestruturaRESUMO
In this study, the effect of inorganic polyphosphate (polyP) on the initial phase of angiogenesis and vascularization was investigated, applying the HUVEC cell tube formation assay. PolyP is a physiological and high energy phosphate polymer which has been proposed to act as a metabolic fuel in the extracellular space with only a comparably low ATP content. The experiments revealed that polyP accelerates tube formation of human umbilical vein endothelial cells (HUVEC), seeded onto a solidified basement membrane extract matrix which contains polyP-metabolizing alkaline phosphatase (ALP) activity. This effect is abolished by co-addition of apyrase, which degrades ATP to AMP and inorganic phosphate. The assumption that ATP, derived from polyP, activates HUVEC cells leading to tube formation was corroborated by experiments showing that addition of polyP to the cells causes a strong rise of ATP level in the culture medium. Finally, we show that at a later stage of cultivation of HUVEC cells, after 3 d, polyP causes a strong enhancement of the expression of the genes encoding for the two major matrix metalloproteinases (MMPs) released by endothelial cells during tube formation, MMP-9 and MMP-2. This stimulatory effect is again abrogated by addition of apyrase together with polyP. From these results, we propose that polyP is involved either directly or indirectly in energy supply, via ALP-mediated transfer of energy-rich phosphate under ATP formation. This ATP is utilized for the activation and oriented migration of endothelial cells and for the matrix organization during the initial phases of tube formation.
Assuntos
Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Microvasos/efeitos dos fármacos , Polifosfatos/farmacologia , Trifosfato de Adenosina/metabolismo , Fosfatase Alcalina/metabolismo , Apirase/farmacologia , Linhagem Celular Tumoral , Células Cultivadas , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/fisiologia , Humanos , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Microscopia Eletrônica de Varredura , Microscopia de Fluorescência , Microvasos/metabolismo , Microvasos/ultraestruturaRESUMO
To date, the role of microvascular pathology and chronic cerebral hypoperfusion (CHH) in the development of mild cognitive impairment in Parkinson's disease (PD-MCI) is unclear. Here, we investigated how the combined injury through interaction of CHH and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) toxicity act as an exacerbating element to damagae cognitive fuction in a mouse model. In the present study, C57BL/6 mice underwent MPTP injection. Subjects were classified into a PD with normal cognitive performance (PDCN) group or a PD-MCI group using the Morris Water Maze test. Further, CHH was induced by stenosis of the bilateral common carotid arteries (BCCAs). Consequently, the animals were divided into 7 groups: they are control, sham, BCCAs, PDCN, PD-MCI, PDCN+BCCAs and PD-MCI+BCCAs. The Morris Water Maze test, open field test, histological investigation and western blotting were performed to analyze cerebral microvascular impairment in each group. The results showed that CHH and MPTP injection caused spatial memory and behavioral impairment, accompanied by microvascular impairment and down-regulation of ZO-1 and Occludin at the protein level compared to the control group. The above injuries were synergistically exacerbated in the PDCN+BCCAs group and the PD-MCI+BCCAs group, which paralleled the elevated expression of p-MAPK and p-Akt. In short, our data demonstrate that CHH and MPTP caused cognitive and microvascular impairment separately. Moreover, CHH may exacerbate cognitive impairment in a mouse model of PD. The study provides a new opportunity for understanding the pathogenesis of PD-MCI.
Assuntos
Doenças das Artérias Carótidas/complicações , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/patologia , Microvasos/patologia , Transtornos Parkinsonianos/complicações , Animais , Antígenos CD34/metabolismo , Modelos Animais de Doenças , Comportamento Exploratório/fisiologia , Deficiências da Aprendizagem/etiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Microvasos/ultraestrutura , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Movimento/fisiologia , Proteína Oncogênica v-akt/metabolismo , Proteína da Zônula de Oclusão-1/metabolismoRESUMO
Aquaporin-4 (AQP4), the predominant water channel in the brain, is expressed in astrocytes and ependymal cells. In rodents AQP4 is highly polarized to perivascular astrocytic endfeet and loss of AQP4 polarization is associated with disease. The present study was undertaken to compare the expression pattern of AQP4 in human and mouse cortical astrocytes. Cortical tissue specimens were sampled from 11 individuals undergoing neurosurgery wherein brain tissue was removed as part of the procedure, and compared with cortical tissue from 5 adult wild-type mice processed similarly. The tissue samples were immersion-fixed and prepared for AQP4 immunogold electron microscopy, allowing quantitative assessment of AQP4's subcellular distribution. In mouse we found that AQP4 water channels were prominently clustered around vessels, being 5 to 10-fold more abundant in astrocytic endfoot membranes facing the capillary endothelium than in parenchymal astrocytic membranes. In contrast, AQP4 was markedly less polarized in human astrocytes, being only two to three-fold enriched in astrocytic endfoot membranes adjacent to capillaries. The lower degree of AQP4 polarization in human subjects (1/3 of that in mice) was mainly due to higher AQP4 expression in parenchymal astrocytic membranes. We conclude that there are hitherto unrecognized species differences in AQP4 polarization toward microvessels in the cerebral cortex.
Assuntos
Aquaporina 4/metabolismo , Astrócitos/metabolismo , Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/metabolismo , Microvasos/metabolismo , Adulto , Idoso , Animais , Astrócitos/ultraestrutura , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Membrana Celular/metabolismo , Membrana Celular/ultraestrutura , Córtex Cerebral/cirurgia , Córtex Cerebral/ultraestrutura , Estudos de Coortes , Epilepsia/metabolismo , Epilepsia/patologia , Epilepsia/cirurgia , Feminino , Humanos , Imuno-Histoquímica , Aneurisma Intracraniano/metabolismo , Aneurisma Intracraniano/patologia , Aneurisma Intracraniano/cirurgia , Masculino , Camundongos Endogâmicos C57BL , Microscopia Eletrônica , Microvasos/ultraestrutura , Pessoa de Meia-Idade , Adulto JovemRESUMO
Nintedanib, a tyrosine kinase inhibitor approved for the treatment of idiopathic pulmonary fibrosis, has anti-fibrotic, anti-inflammatory, and anti-angiogenic activity. We explored the impact of nintedanib on microvascular architecture in a pulmonary fibrosis model. Lung fibrosis was induced in C57Bl/6 mice by intratracheal bleomycin (0.5 mg/kg). Nintedanib was started after the onset of lung pathology (50 mg/kg twice daily, orally). Micro-computed tomography was performed via volumetric assessment. Static lung compliance and forced vital capacity were determined by invasive measurements. Mice were subjected to bronchoalveolar lavage and histologic analyses, or perfused with a casting resin. Microvascular corrosion casts were imaged by scanning electron microscopy and synchrotron radiation tomographic microscopy, and quantified morphometrically. Bleomycin administration resulted in a significant increase in higher-density areas in the lungs detected by micro-computed tomography, which was significantly attenuated by nintedanib. Nintedanib significantly reduced lung fibrosis and vascular proliferation, normalized the distorted microvascular architecture, and was associated with a trend toward improvement in lung function and inflammation. Nintedanib resulted in a prominent improvement in pulmonary microvascular architecture, which outperformed the effect of nintedanib on lung function and inflammation. These findings uncover a potential new mode of action of nintedanib that may contribute to its efficacy in idiopathic pulmonary fibrosis.
Assuntos
Fibrose Pulmonar Idiopática/tratamento farmacológico , Indóis/uso terapêutico , Microvasos/ultraestrutura , Animais , Bleomicina , Proliferação de Células/efeitos dos fármacos , Colágeno/metabolismo , Modelos Animais de Doenças , Fibrose Pulmonar Idiopática/diagnóstico por imagem , Fibrose Pulmonar Idiopática/patologia , Fibrose Pulmonar Idiopática/fisiopatologia , Imageamento Tridimensional , Camundongos Endogâmicos C57BL , Microvasos/diagnóstico por imagem , Microvasos/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Pneumonia/complicações , Pneumonia/diagnóstico por imagem , Pneumonia/patologia , Pneumonia/fisiopatologia , Alvéolos Pulmonares/efeitos dos fármacos , Alvéolos Pulmonares/patologia , Alvéolos Pulmonares/ultraestrutura , Testes de Função Respiratória , Microtomografia por Raio-XRESUMO
Angiogenesis is essential for tumor growth, and an enhanced vasculature supplying nutrients and oxygen might reflect malignant potential. L-type amino acid transporter 1 (LAT1/4F2hc) comprises a major nutrient transport system responsible for the Na+-independent transport of large neutral amino acids. Seventy five to seventy eight percent N-butyl-N-(4-hydroxybutyl) nitrosamine-induced rat bladder carcinoma cells showed high LAT1/4F2hc expression. While the intracarcinoma microvasculatures of fenestrated endothelial cells highly expressing LAT1/4F2hc might progressively transport essential amino acids from the microvasculatures to the extracellular matrix, non-fenestrated endothelial cells and pericytes did not. The present study revealed that the tumor angiogenesis is one of target anti-L-type amino acid transporter 1 drug.
Assuntos
Butilidroxibutilnitrosamina/efeitos adversos , Cadeia Pesada da Proteína-1 Reguladora de Fusão/ultraestrutura , Transportador 1 de Aminoácidos Neutros Grandes/química , Microvasos/ultraestrutura , Neoplasias da Bexiga Urinária/irrigação sanguínea , Neoplasias da Bexiga Urinária/ultraestrutura , Animais , Imuno-Histoquímica/métodos , Transportador 1 de Aminoácidos Neutros Grandes/ultraestrutura , Masculino , Microscopia Eletrônica , Ratos , Ratos Wistar , Neoplasias da Bexiga Urinária/induzido quimicamenteRESUMO
BACKGROUND: Amyloid peptide precursor (APP) as the precursor protein of peptide betaamyloid (ß-amyloid, Aß), which is thought to play a central role in the pathogenesis of Alzheimer's disease (AD), also has an important effect on the development and progression of AD. Through knocking-in APP gene in animals, numerous transgenic AD models have been set up for the investigation of the mechanisms behind AD pathogenesis and the screening of anti-AD drugs. However, there are some limitations to these models and here is a need for such an AD model that is economic as well as has satisfactory genetic homology with human. METHODS: We generated a new AD transgenic model by knocking a mutant human APP gene (APPsw) in zebrafish with appb promoter of zebrafish to drive the expression of APPsw. RESULTS: Fluorescent image and immunochemistry stain showed and RT-PCR and western blot assay confirmed that APPsw was successfully expressed in the brain, heart, eyes and vasculature of the transgenic zebrafish. Behavioral observation demonstrated that the transgenic zebrafish had AD-like symptoms. Histopathological observation found that there were cerebral ß-amyloidosis and angiopathy (CAA), which induced neuron loss and enlarged pervascular space. CONCLUSION: These results suggest that APPsw transgenic zebrafish well simulate the pathological characters of AD and can be used as an economic AD transgenic model. Furthermore, the new model suggested that APP can express in microvasculatures and cause the Aß generation and deposition in cerebral vessel which further destroys cerebral vascular structure resulting in the development and/or the progress of AD.
Assuntos
Doença de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Angiopatia Amiloide Cerebral/etiologia , Regulação da Expressão Gênica/genética , Mutação/genética , Regiões Promotoras Genéticas/fisiologia , Doença de Alzheimer/complicações , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Amiloidose/etiologia , Animais , Animais Geneticamente Modificados , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/ultraestrutura , Angiopatia Amiloide Cerebral/genética , Modelos Animais de Doenças , Comportamento Exploratório/fisiologia , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Aprendizagem em Labirinto/fisiologia , Microscopia Eletrônica de Transmissão , Microvasos/metabolismo , Microvasos/patologia , Microvasos/ultraestrutura , RNA Mensageiro/metabolismo , Peixe-ZebraRESUMO
Nucleoside diphosphate kinase B (NDPK-B) is an enzyme required for nucleoside triphosphate homeostasis, which has been shown to interact with caveolin-1 (Cav-1). In endothelial cells (ECs), NDPK-B contributes to the regulation of angiogenesis and adherens junction (AJ) integrity. We therefore investigated whether an interaction of NDPK-B with Cav-1 in ECs is required for this regulation and the involvement of VEGF signaling herein. We report that simultaneous depletion of NDPK-B/Cav-1 in HUVECs synergistically impaired sprouting angiogenesis. NDPK-B depletion alone impaired caveolae formation, VEGF-induced phosphorylation of c-Src/Cav-1 but not of ERK1/2/AKT/eNOS. In vivo, Cav-1-/- mice showed impaired retinal vascularization at postnatal-day five, whereas NDPK-B-/- mice did not. Primary mouse brain ECs (MBMECs) from NDPK-B-/- mice showed no change in caveolae content and transendothelial-electrical resistance upon VEGF stimulation. Interestingly, NDPK-B-/- MBMECs displayed an accumulation of intracellular vesicles and increased Cav-1 levels. Dextran tracer analysis showed increased vascular permeability in the brain of NDPK-B-/- mice compared to wild type. In conclusion, our data indicate that NDPK-B is required for the correct localization of Cav-1 at the plasma membrane and the formation of caveolae. The genetic ablation of NDPK-B could partially be compensated by an increased Cav-1 content, which restored caveolae formation and some endothelial functions.
Assuntos
Cavéolas/metabolismo , Caveolina 1/metabolismo , Endotélio Vascular/metabolismo , Nucleosídeo NM23 Difosfato Quinases/metabolismo , Neovascularização Fisiológica/fisiologia , Quinases da Família src/metabolismo , Animais , Encéfalo/irrigação sanguínea , Proteína Tirosina Quinase CSK , Cavéolas/ultraestrutura , Caveolina 1/genética , Membrana Celular/enzimologia , Membrana Celular/metabolismo , Membrana Celular/ultraestrutura , Permeabilidade da Membrana Celular , Células Endoteliais , Endotélio Vascular/enzimologia , Endotélio Vascular/ultraestrutura , Células Endoteliais da Veia Umbilical Humana , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica , Microvasos/citologia , Microvasos/metabolismo , Microvasos/ultraestrutura , Nucleosídeo NM23 Difosfato Quinases/genética , Neovascularização Fisiológica/genética , Fosforilação , Vasos Retinianos/crescimento & desenvolvimento , Vasos Retinianos/metabolismo , Vasos Retinianos/ultraestrutura , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
The renal microvasculature is targeted during aging, sometimes producing chronic kidney disease (CKD). Overdiagnosis of CKD in older persons is concerning. To prevent it, a new concept of "healthy aging" is arising from a healthy renal donor study. We investigated the renal microcirculatory changes of three older persons and compared them with that of one patient with nephrosclerosis using a three-dimensional (3D) reconstruction technique that we previously developed. This method uses a virtual slide system and paraffin-embedded serial sections of surgical material that was double-immunostained by anti-CD34 and anti-α smooth muscle actin (SMA) antibodies for detecting endothelial cells and medial smooth muscle cells, respectively. In all cases, the 3D images proved that arteriosclerotic changes in large proximal interlobular arteries did not directly induce distal arterial change or glomerulosclerosis. The nephrosclerotic patient showed severe hyalinosis with luminal narrowing of small arteries directly inducing glomerulosclerosis. We also visualized an atubular glomerulus and intraglomerular dilatation of an afferent arteriole during healthy aging on the 3D image and showed that microcirculatory changes were responsible for them. Thus, we successfully visualized healthy aged kidneys on 3D images and confirmed the underlying pathology. This method has the ability to investigate renal microcirculatory damage during healthy aging.
Assuntos
Adenocarcinoma de Células Claras/diagnóstico por imagem , Envelhecimento/patologia , Carcinoma de Células Renais/diagnóstico por imagem , Imageamento Tridimensional/métodos , Glomérulos Renais/diagnóstico por imagem , Neoplasias Renais/diagnóstico por imagem , Microvasos/diagnóstico por imagem , Nefroesclerose/diagnóstico por imagem , Actinas/genética , Actinas/metabolismo , Adenocarcinoma de Células Claras/irrigação sanguínea , Adenocarcinoma de Células Claras/metabolismo , Adenocarcinoma de Células Claras/ultraestrutura , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/metabolismo , Antígenos CD34/genética , Antígenos CD34/metabolismo , Biomarcadores/metabolismo , Carcinoma de Células Renais/irrigação sanguínea , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/ultraestrutura , Células Endoteliais/metabolismo , Células Endoteliais/ultraestrutura , Expressão Gênica , Humanos , Glomérulos Renais/irrigação sanguínea , Glomérulos Renais/ultraestrutura , Neoplasias Renais/irrigação sanguínea , Neoplasias Renais/metabolismo , Neoplasias Renais/ultraestrutura , Masculino , Microtomia , Microvasos/metabolismo , Microvasos/ultraestrutura , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/ultraestrutura , Nefroesclerose/metabolismo , Nefroesclerose/patologia , Inclusão do TecidoRESUMO
Angiogenesis, defined as the growth of new blood vessels from existing ones, plays a key role in development, growth, and tissue repair. Its necessary role in tumor growth and metastasis has led to the creation of a new category of anti-angiogenic cancer therapies. Preclinical development and evaluation of potential drug candidates require models that mimic real microvascular networks. Here, we describe the rat mesentery culture model as a simple ex vivo assay that offers time-lapse imaging of intact microvascular network remodeling and demonstrate its application for anti-angiogenic drug testing.
Assuntos
Inibidores da Angiogênese/farmacologia , Mesentério/citologia , Microvasos/ultraestrutura , Técnicas de Cultura de Tecidos/métodos , Animais , Avaliação Pré-Clínica de Medicamentos , Mesentério/irrigação sanguínea , Mesentério/efeitos dos fármacos , Microvasos/efeitos dos fármacos , Modelos Biológicos , Ratos , Ratos Wistar , Imagem com Lapso de TempoRESUMO
Many drugs have been reported to cause thrombotic microangiopathy (TMA), yet evidence supporting a direct association is often weak. In particular, TMA has been reported in association with recombinant type I interferon (IFN) therapies, with recent concern regarding the use of IFN in multiple sclerosis patients. However, a causal association has yet to be demonstrated. Here, we adopt a combined clinical and experimental approach to provide evidence of such an association between type I IFN and TMA. We show that the clinical phenotype of cases referred to a national center is uniformly consistent with a direct dose-dependent drug-induced TMA. We then show that dose-dependent microvascular disease is seen in a transgenic mouse model of IFN toxicity. This includes specific microvascular pathological changes seen in patient biopsies and is dependent on transcriptional activation of the IFN response through the type I interferon α/ß receptor (IFNAR). Together our clinical and experimental findings provide evidence of a causal link between type I IFN and TMA. As such, recombinant type I IFN therapies should be stopped at the earliest stage in patients who develop this complication, with implications for risk mitigation.