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1.
Mol Med Rep ; 24(4)2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34328194

RESUMO

Previous studies have suggested that oxidative stress and autophagy results in acute kidney injury (AKI) during sepsis and microRNA (miR)­214 serves a vital role in the protection of kidneys subjected to oxidative stress. The present study aimed to test whether the renoprotection of miR­214 is related to autophagy in sepsis. The role of autophagy was investigated in a mouse model of cecal ligation and puncture (CLP). Reverse transcription­quantitative polymerase chain reaction (RT­qPCR) was used to analyze the expression of miR­214. The structure and function of kidneys harvested from the mice were evaluated. Kidney autophagy levels were detected with immunohistochemical, immunofluorescent and western blotting. It was found that miR­214 could alleviate AKI in septic mice by inhibiting the level of kidney autophagy. Furthermore, miR­214 inhibited autophagy by silencing PTEN expression in the kidney tissues of septic mice. These findings indicated that miR­214 ameliorated CLP­induced AKI by reducing oxidative stress and inhibiting autophagy through the regulation of the PTEN/AKT/mTOR pathway.


Assuntos
Injúria Renal Aguda/genética , Autofagia/genética , MicroRNAs/genética , MicroRNAs/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/patologia , Animais , Ceco/lesões , Ceco/microbiologia , Modelos Animais de Doenças , Rim/metabolismo , Rim/patologia , Rim/ultraestrutura , Ligadura , Masculino , Camundongos , Estresse Oxidativo/genética , PTEN Fosfo-Hidrolase/genética , Punções , Sepse/complicações , Transdução de Sinais/genética
2.
Commun Biol ; 4(1): 710, 2021 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-34112923

RESUMO

Immunocytochemistry visualizes the exact spatial location of target molecules. The most common strategy for ultrastructural immunocytochemistry is the conjugation of nanogold particles to antibodies as probes. However, conventional nanogold labelling requires time-consuming nanogold probe preparation and ultrathin sectioning of cell/tissue samples. Here, we introduce an in situ strategy involving nanogold nucleation in immunoenzymatic products on universal paraffin/cryostat sections and provide unique insight into nanogold development under hot-humid air conditions. Nanogold particles were specifically localized on kidney podocytes to target synaptopodin. Transmission electron microscopy revealed secondary growth and self-assembly that could be experimentally controlled by bovine serum albumin stabilization and phosphate-buffered saline acceleration. Valuable retrospective nanogold labelling for gastric H+/K+-ATPase was achieved on vintage immunoenzymatic deposits after a long lapse of 15 years (i.e., 15-year-old deposits). The present in situ nanogold labelling is anticipated to fill the gap between light and electron microscopy to correlate cell/tissue structure and function.


Assuntos
Ouro/análise , Nanopartículas Metálicas/análise , Animais , Feminino , Imuno-Histoquímica , Rim/ultraestrutura , Masculino , Camundongos Endogâmicos C57BL , Proteínas dos Microfilamentos/análise , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Ovário/ultraestrutura , Coelhos , Ratos Wistar , Coloração e Rotulagem
3.
Nat Commun ; 12(1): 2886, 2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-34001900

RESUMO

The brush border is comprised of microvilli surface protrusions on the apical surface of epithelia. This specialized structure greatly increases absorptive surface area and plays crucial roles in human health. However, transcriptional regulatory networks controlling brush border genes are not fully understood. Here, we identify that hepatocyte nuclear factor 4 (HNF4) transcription factor is a conserved and important regulator of brush border gene program in multiple organs, such as intestine, kidney and yolk sac. Compromised brush border gene signatures and impaired transport were observed in these tissues upon HNF4 loss. By ChIP-seq, we find HNF4 binds and activates brush border genes in the intestine and kidney. H3K4me3 HiChIP-seq identifies that HNF4 loss results in impaired chromatin looping between enhancers and promoters at gene loci of brush border genes, and instead enhanced chromatin looping at gene loci of stress fiber genes in the intestine. This study provides comprehensive transcriptional regulatory mechanisms and a functional demonstration of a critical role for HNF4 in brush border gene regulation across multiple murine epithelial tissues.


Assuntos
Regulação da Expressão Gênica , Fator 4 Nuclear de Hepatócito/genética , Mucosa Intestinal/metabolismo , Rim/metabolismo , Microvilosidades/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Saco Vitelino/metabolismo , Animais , Epitélio/metabolismo , Perfilação da Expressão Gênica/métodos , Fator 4 Nuclear de Hepatócito/metabolismo , Humanos , Intestinos/ultraestrutura , Rim/ultraestrutura , Camundongos Knockout , Camundongos Transgênicos , Microscopia Eletrônica de Transmissão , Receptores Citoplasmáticos e Nucleares/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
4.
Biomed Res Int ; 2021: 5598351, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33969119

RESUMO

Hypertensive-induced renal damage (HRD) is an important public health and socioeconomic problem worldwide. The herb pair Radix Astragali- (RA-) Radix Salviae Miltiorrhizae (RS) is a common prescribed herbal formula for the treatment of HRD. However, the underlying mechanisms are unclear. The purpose of our study is to explore the mechanism of combination of Radix Astragali (RA) and Radix Salviae Miltiorrhizae (RS) ameliorating HRD by regulation of the renal sympathetic nerve. Thirty 24-week-old spontaneously hypertensive rats (SHRs) as the experimental group were randomly divided into the RA group, the RS group, the RA+RS group, the valsartan group, and the SHR group and six age-matched Wistar Kyoto rats (WKY) as the control group. After 4 weeks of corresponding drug administration, venipuncture was done to collect blood and prepare serum for analysis. A color Doppler ultrasound diagnostic instrument was used to observe renal hemodynamics. Enzyme-linked immunosorbent assay was used to detect norepinephrine (NE), epinephrine (E), angiotensin II (Ang II), and B-type brain natriuretic peptide (BNP). Simultaneously, the kidneys were removed immediately and observed under a transmission electron microscope to observe the ultrastructural changes. And the concentration of transforming growth factor-ß1 (TGF-ß1), angiotensin type 1 receptor (AT1), and nitric oxide (NO) was detected by immunohistochemistry. Our results showed that renal ultrasonography of rats showed no significant difference in renal size among groups. The RA+RS group had obviously decreased vascular resistance index. The levels of NE, E, BNP, Ang II, AT1, and TGF-ß1 were decreased (P < 0.05), and the density of NO was increased. Pathological damage of the kidney was alleviated. In conclusion, the results of the present study suggested sympathetic overexpression in the pathogenesis of HRD. The combination of RA and RS may inhibit the hyperexcitability of sympathetic nerves and maintain the normal physiological structure and function of kidney tissue and has a protective effect on the cardiovascular system.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Hipertensão/tratamento farmacológico , Rim/patologia , Salvia miltiorrhiza/química , Animais , Biomarcadores/sangue , Medicamentos de Ervas Chinesas/farmacologia , Hemodinâmica/efeitos dos fármacos , Hipertensão/sangue , Hipertensão/fisiopatologia , Rim/diagnóstico por imagem , Rim/fisiopatologia , Rim/ultraestrutura , Masculino , Modelos Biológicos , Óxido Nítrico/metabolismo , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Receptor Tipo 1 de Angiotensina/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Resistência Vascular/efeitos dos fármacos
5.
Philos Trans A Math Phys Eng Sci ; 379(2199): 20200300, 2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-33896201

RESUMO

Fluorescence-based microscopy as one of the standard tools in biomedical research benefits more and more from super-resolution methods, which offer enhanced spatial resolution allowing insights into new biological processes. A typical drawback of using these methods is the need for new, complex optical set-ups. This becomes even more significant when using two-photon fluorescence excitation, which offers deep tissue imaging and excellent z-sectioning. We show that the generation of striped-illumination patterns in two-photon laser scanning microscopy can readily be exploited for achieving optical super-resolution and contrast enhancement using open-source image reconstruction software. The special appeal of this approach is that even in the case of a commercial two-photon laser scanning microscope no optomechanical modifications are required to achieve this modality. Modifying the scanning software with a custom-written macro to address the scanning mirrors in combination with rapid intensity switching by an electro-optic modulator is sufficient to accomplish the acquisition of two-photon striped-illumination patterns on an sCMOS camera. We demonstrate and analyse the resulting resolution improvement by applying different recently published image resolution evaluation procedures to the reconstructed filtered widefield and super-resolved images. This article is part of the Theo Murphy meeting issue 'Super-resolution structured illumination microscopy (part 1)'.


Assuntos
Microscopia de Fluorescência por Excitação Multifotônica/instrumentação , Algoritmos , Animais , Convallaria/ultraestrutura , Processamento de Imagem Assistida por Computador/métodos , Processamento de Imagem Assistida por Computador/estatística & dados numéricos , Rim/ultraestrutura , Camundongos , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Microscopia de Fluorescência por Excitação Multifotônica/estatística & dados numéricos , Dispositivos Ópticos , Fenômenos Ópticos , Software
6.
Clin J Am Soc Nephrol ; 16(5): 685-693, 2021 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-33782033

RESUMO

BACKGROUND AND OBJECTIVES: AKI in coronavirus disease 2019 (COVID-19) is associated with higher morbidity and mortality. The objective of this study was to identify the kidney histopathologic characteristics of deceased patients with diagnosis of COVID-19 and evaluate the association between biopsy findings and clinical variables, including AKI severity. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Our multicenter, observational study of deceased patients with COVID-19 in three third-level centers in Mexico City evaluated postmortem kidney biopsy by light and electron microscopy analysis in all cases. Descriptive and association statistics were performed between the clinical and histologic variables. RESULTS: A total of 85 patients were included. Median age was 57 (49-66) years, 69% were men, body mass index was 29 (26-35) kg/m2, 51% had history of diabetes, 46% had history of hypertension, 98% received anticoagulation, 66% were on steroids, and 35% received at least one potential nephrotoxic medication. Severe AKI was present in 54% of patients. Biopsy findings included FSGS in 29%, diabetic nephropathy in 27%, and arteriosclerosis in 81%. Acute tubular injury grades 2-3 were observed in 49%. Histopathologic characteristics were not associated with severe AKI; however, pigment casts on the biopsy were associated with significantly lower probability of kidney function recovery (odds ratio, 0.07; 95% confidence interval, 0.01 to 0.77). The use of aminoglycosides/colistin, levels of C-reactive protein and serum albumin, previous use of angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers, antivirals, nonsteroid anti-inflammatory drugs, and anticoagulants were associated with specific histopathologic findings. CONCLUSIONS: A high prevalence of chronic comorbidities was found on kidney biopsies. Nonrecovery from severe AKI was associated with the presence of pigmented casts. Inflammatory markers and medications were associated with specific histopathologic findings in patients dying from COVID-19.


Assuntos
Injúria Renal Aguda/patologia , COVID-19/patologia , Rim/patologia , SARS-CoV-2 , Idoso , Biópsia , Feminino , Humanos , Rim/ultraestrutura , Masculino , Pessoa de Meia-Idade
7.
Virchows Arch ; 479(1): 57-67, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33447899

RESUMO

Clear cytoplasm is a major characteristic feature of most malignant renal neoplasms. Benign clear cells in the renal parenchyma, usually histiocytes, can occasionally be found, but they are infrequently of an epithelial nature. We report histological, immunohistochemical, ultrastructural, and cytogenomic features of clear epithelial cell clusters incidentally found in four kidney specimens. Multiple microscopic clear cell clusters were present in the cortex, often in subcapsular location. They were composed of large epithelial cells with strikingly clear cytoplasm, without nuclear atypia, arranged in solid nests, and some tubules with narrow lumina. Immunohistochemically, they were positive for AE1AE3, PAX 8, EMA, kidney-specific cadherin, cytokeratin 7, E cadherin, and CD117, with focal immunoreactivity for CD10. Carbonic anhydrase IX, vimentin, and markers related to apoptosis and proliferation were negative. Ultrastructurally, the cytoplasms were enlarged and poor in organelles, showing ballooning degeneration. Array comparative genomic hybridization showed no chromosomal gains or losses. Clear cell clusters constitute a rare finding in the kidney and must be differentiated from benign lesions (ectopic adrenal tissue, osmotic tubulopathy, histiocytic clusters, renal adenomas) and renal cell carcinomas. Clear cell clusters appear to be generated from "endocrine-type" atrophic tubules whose cells are enlarged due to intracellular oedema. Immunohistochemistry shows a distal nephron phenotype with a limited expression of a proximal marker, CD10. Coexisting chronic renal disease or ischemic conditions seem to be related to the development of clear cell clusters. Pathological, ultrastructural, and cytogenomic features do not support a preneoplastic nature of this lesion, at least in the cases studied here.


Assuntos
Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Rim/patologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/análise , Carcinoma de Células Renais/química , Carcinoma de Células Renais/ultraestrutura , Hibridização Genômica Comparativa , Diagnóstico Diferencial , Erros de Diagnóstico , Feminino , Humanos , Imuno-Histoquímica , Rim/química , Rim/ultraestrutura , Neoplasias Renais/química , Neoplasias Renais/ultraestrutura , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Fenótipo , Valor Preditivo dos Testes
8.
Biomolecules ; 11(1)2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33430288

RESUMO

Renal injury observed in several pathologies has been associated with lipid accumulation in the kidney. While it has been suggested that the accumulation of renal lipids depends on free fatty acids released from adipose tissue, it is not known whether in situ renal lipogenesis due to endoplasmic reticulum (ER) stress contributes to kidney injury. The aim of the present study was to elucidate the role of pharmacological ER stress in renal structure and function and its effect on renal lipid metabolism of C57BL/6 mice. ER stress increased serum creatinine and induced kidney structural abnormalities. Tunicamycin-administered mice developed hyperinsulinemia, augmented lipolysis and increased circulating leptin and adiponectin. Renal unfolded protein response (UPR) gene expression markers, the lipogenic transcription factor SREBP1 and the phosphorylation of eIF2α increased 8 h after tunicamycin administration. At 24 h, an increase in BiP protein content was accompanied by a reduction in p-eIF2α and increased SREBP-1 and FASn protein content, in addition to a significant increase in triglyceride content and a reduction in AMPK. Thus, ER stress induces in situ lipid synthesis, leading to renal lipid accumulation and functional alterations. Future pharmacological and/or dietary strategies must target renal ER stress to prevent kidney damage and the progression of metabolic diseases.


Assuntos
Rim/metabolismo , Lipogênese , Resposta a Proteínas não Dobradas , Animais , Peso Corporal , Sistema Endócrino/efeitos dos fármacos , Sistema Endócrino/metabolismo , Estresse do Retículo Endoplasmático , Rim/patologia , Rim/fisiopatologia , Rim/ultraestrutura , Masculino , Redes e Vias Metabólicas , Camundongos Endogâmicos C57BL , Tamanho do Órgão , Tunicamicina/administração & dosagem
9.
Lupus ; 30(4): 587-596, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33413002

RESUMO

INTRODUCTION: Renal involvement is seen in about 40-82% of systemic lupus erythematosus (SLE) Asian patients. The exact diagnosis and classification of lupus nephritis are important for treatment and prognosis. This study aimed to investigate the value of electron microscopy (EM) in the diagnosis and classification of lupus nephritis compared with light microscopy. METHOD: In this cross-sectional referral-center 16-year study of lupus nephritis, the final diagnosis was based on the EM study. Primary light microscopy findings were compared with EM diagnosis. Moreover, Immunofluorescence patterns distribution was assessed. RESULTS: From 496 patients diagnosed with lupus nephritis based on EM, 225(45.4%) of patients were categorized in class IV, followed by 98(19.7%), 93(18.8%), 46(9.3%), and 14(2.8%) who were categorized into classes of II, III, V, and VI respectively. Only 1(0.2%) patient belonged to class I, and 19(3.8%) cases were diagnosed with mixed two classes. Using EM was essential for diagnosing 25.6% of cases taking the correct classification by light microscopy into account; however, disregarding correct classification, this could change to a 7.4% contribution rate of EM. The most common cause of misdiagnosis, disregarding incorrect classification, was inadequate or wrong tissue. Positive associations were detected between tubular atrophy and interstitial fibrosis of both electron and light microscopy with different classes (P < 0.001). CONCLUSION: While light microscopy is highly accurate for diagnosing lupus nephritis regardless of correct classification, EM contributes substantially to the correct classification of lupus nephritis types.


Assuntos
Mesângio Glomerular/ultraestrutura , Túbulos Renais/ultraestrutura , Lúpus Eritematoso Sistêmico/patologia , Nefrite Lúpica/patologia , Microscopia Eletrônica/estatística & dados numéricos , Microscopia/estatística & dados numéricos , Adolescente , Adulto , Idoso , Grupo com Ancestrais do Continente Asiático/etnologia , Atrofia/diagnóstico , Biópsia , Estudos Transversais , Erros de Diagnóstico/estatística & dados numéricos , Feminino , Fibrose/diagnóstico , Imunofluorescência/métodos , Mesângio Glomerular/patologia , Humanos , Rim/patologia , Rim/ultraestrutura , Túbulos Renais/patologia , Lúpus Eritematoso Sistêmico/complicações , Nefrite Lúpica/classificação , Nefrite Lúpica/diagnóstico , Masculino , Microscopia/métodos , Microscopia Eletrônica/métodos , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Adulto Jovem
10.
Nucleic Acids Res ; 49(1): 1-14, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33275144

RESUMO

Nucleic acid therapeutics (NATs) have proven useful in promoting the degradation of specific transcripts, modifying gene expression, and regulating mRNA splicing. In each situation, efficient delivery of nucleic acids to cells, tissues and intracellular compartments is crucial-both for optimizing efficacy and reducing side effects. Despite successes in NATs, our understanding of their cellular uptake and distribution in tissues is limited. Current methods have yielded insights into distribution of NATs within cells and tissues, but the sensitivity and resolution of these approaches are limited. Here, we show that nanoscale secondary ion mass spectrometry (NanoSIMS) imaging can be used to define the distribution of 5-bromo-2'-deoxythymidine (5-BrdT) modified antisense oligonucleotides (ASO) in cells and tissues with high sensitivity and spatial resolution. This approach makes it possible to define ASO uptake and distribution in different subcellular compartments and to quantify the impact of targeting ligands designed to promote ASO uptake by cells. Our studies showed that phosphorothioate ASOs are associated with filopodia and the inner nuclear membrane in cultured cells, and also revealed substantial cellular and subcellular heterogeneity of ASO uptake in mouse tissues. NanoSIMS imaging represents a significant advance in visualizing uptake and distribution of NATs; this approach will be useful in optimizing efficacy and delivery of NATs for treating human disease.


Assuntos
Oligonucleotídeos Antissenso/análise , Oligonucleotídeos Fosforotioatos/análise , Espectrometria de Massa de Íon Secundário/métodos , Células 3T3-L1 , Acetilgalactosamina/administração & dosagem , Acetilgalactosamina/análise , Animais , Receptor de Asialoglicoproteína/análise , Césio , Células HEK293 , Células HeLa , Humanos , Rim/química , Rim/ultraestrutura , Fígado/química , Fígado/ultraestrutura , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica , Miocárdio/química , Miocárdio/ultraestrutura , Oligonucleotídeos Antissenso/farmacocinética , Oligonucleotídeos Fosforotioatos/farmacocinética , Pseudópodes/química , Pseudópodes/ultraestrutura , RNA Longo não Codificante/antagonistas & inibidores , RNA Longo não Codificante/biossíntese , RNA Longo não Codificante/genética , Frações Subcelulares/química , Enxofre/análise , Isótopos de Enxofre/análise , Distribuição Tecidual
11.
Anal Bioanal Chem ; 413(4): 1203-1214, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33277998

RESUMO

Immunofluorescence microscopy is routinely used in the diagnosis of and research on renal impairments. However, this highly specific technique is restricted in its maximum resolution to about 250 nm in the lateral and 700 nm in the axial directions and thus not sufficient to investigate the fine subcellular structure of the kidney's glomerular filtration barrier. In contrast, electron microscopy offers high resolution, but this comes at the cost of poor preservation of immunogenic epitopes and antibody penetration alongside a low throughput. Many of these drawbacks were overcome with the advent of super-resolution microscopy methods. So far, four different super-resolution approaches have been used to study the kidney: single-molecule localization microscopy (SMLM), stimulated emission depletion (STED) microscopy, structured illumination microscopy (SIM), and expansion microscopy (ExM), however, using different preservation methods and widely varying labelling strategies. In this work, all four methods were applied and critically compared on kidney slices obtained from samples treated with the most commonly used preservation technique: fixation by formalin and embedding in paraffin (FFPE). Strengths and weaknesses, as well as the practicalities of each method, are discussed to enable users of super-resolution microscopy in renal research make an informed decision on the best choice of technique. The methods discussed enable the efficient investigation of biopsies stored in kidney banks around the world. Graphical abstract.


Assuntos
Rim/ultraestrutura , Imagem Individual de Molécula/métodos , Animais , Barreira de Filtração Glomerular , Humanos , Rim/patologia , Proteínas de Membrana/análise , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência , Inclusão em Parafina , Podócitos/patologia , Podócitos/ultraestrutura , Fixação de Tecidos
12.
Nat Protoc ; 16(1): 239-262, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33247285

RESUMO

Advances in light-sheet and confocal microscopy now allow imaging of cleared large biological tissue samples and enable the 3D appreciation of cell and protein localization in their native organ environment. However, the sample preparations for such imaging are often onerous, and their capability for antigen detection is limited. Here, we describe FLASH (fast light-microscopic analysis of antibody-stained whole organs), a simple, rapid, fully customizable technique for molecular phenotyping of intact tissue volumes. FLASH utilizes non-degradative epitope recovery and membrane solubilization to enable the detection of a multitude of membranous, cytoplasmic and nuclear antigens in whole mouse organs and embryos, human biopsies, organoids and Drosophila. Retrieval and immunolabeling of epithelial markers, an obstacle for previous clearing techniques, can be achieved with FLASH. Upon volumetric imaging, FLASH-processed samples preserve their architecture and integrity and can be paraffin-embedded for subsequent histopathological analysis. The technique can be performed by scientists trained in light microscopy and yields results in <1 week.


Assuntos
Antígenos/análise , Imunofluorescência/métodos , Imageamento Tridimensional/métodos , Microscopia Confocal/métodos , Animais , Drosophila , Epitopos/análise , Feminino , Humanos , Rim/ultraestrutura , Aparelho Lacrimal/ultraestrutura , Fígado/ultraestrutura , Pulmão/ultraestrutura , Masculino , Glândulas Mamárias Humanas/ultraestrutura , Camundongos , Organoides/ultraestrutura , Pâncreas/ultraestrutura , Estômago/ultraestrutura
13.
Mayo Clin Proc ; 96(1): 40-51, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33097219

RESUMO

OBJECTIVE: To determine whether microstructural features on a kidney biopsy specimen obtained during kidney transplant surgery predict long-term risk of chronic kidney disease in the donor. PATIENTS AND METHODS: We studied kidney donors from May 1, 1999, through December 31, 2018, with a follow-up survey for the results of recent blood pressure and kidney function tests (estimated glomerular filtration rate [eGFR] and proteinuria). If not recently available, blood pressure and eGFRs were requested from a local clinic. Microstructural features on kidney biopsy at the time of donation were assessed as predictors of hypertension and kidney function after adjusting for years of follow-up, baseline age, sex, and clinical predictors. RESULTS: There were 807 donors surveyed a mean 10.5 years after donation. An eGFR less than 45 mL/min/1.73 m2 in 6.4% (43/673) of donors was predicted by larger glomerular volume per standard deviation (odds ratio [OR], 1.48; 95% CI, 1.08 to 2.04) and nephron number below the age-specific 5th percentile (OR, 3.38; 95% CI, 1.31 to 8.72). An eGFR less than 60 mL/min/1.73 m2 in 42.5% (286/673) of donors was not predicted by any microstructural feature. Residual eGFR (postdonation/predonation eGFR) was predicted by nephron number below the age-specific 5th percentile (difference, -6.07%; 95% CI, -10.24% to -1.89%). Self-reported proteinuria in 5.1% (40/786) of donors was predicted by larger glomerular volume (OR, 1.42; 95% CI, 1.08 to 1.86). Incident hypertension in 18.8% (119/633) of donors was not predicted by any microstructural features. CONCLUSION: Low nephron number for age and larger glomeruli are important microstructural predictors for long-term risk of chronic kidney disease after living kidney donation.


Assuntos
Transplante de Rim , Rim/ultraestrutura , Insuficiência Renal Crônica/etiologia , Doadores de Tecidos , Biópsia , Feminino , Barreira de Filtração Glomerular , Humanos , Hipertensão/etiologia , Rim/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Insuficiência Renal Crônica/patologia , Fatores de Risco
14.
Am J Physiol Regul Integr Comp Physiol ; 320(1): R19-R35, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33085906

RESUMO

C1q/TNF-related protein 1 (CTRP1) is an endocrine factor with metabolic, cardiovascular, and renal functions. We previously showed that aged Ctrp1-knockout (KO) mice fed a control low-fat diet develop renal hypertrophy and dysfunction. Since aging and obesity adversely affect various organ systems, we hypothesized that aging, in combination with obesity induced by chronic high-fat feeding, would further exacerbate renal dysfunction in CTRP1-deficient animals. To test this, we fed wild-type and Ctrp1-KO mice a high-fat diet for 8 mo or longer. Contrary to our expectation, no differences were observed in blood pressure, heart function, or vascular stiffness between genotypes. Loss of CTRP1, however, resulted in an approximately twofold renal enlargement (relative to body weight), ∼60% increase in urinary total protein content, and elevated pH, and changes in renal gene expression affecting metabolism, signaling, transcription, cell adhesion, solute and metabolite transport, and inflammation. Assessment of glomerular integrity, the extent of podocyte foot process effacement, as well as renal response to water restriction and salt loading did not reveal significant differences between genotypes. Interestingly, blood platelet, white blood cell, neutrophil, lymphocyte, and eosinophil counts were significantly elevated, whereas mean corpuscular volume and hemoglobin were reduced in Ctrp1-KO mice. Cytokine profiling revealed increased circulating levels of CCL17 and TIMP-1 in KO mice. Compared with our previous study, current data suggest that chronic high-fat feeding affects renal phenotypes differently than similarly aged mice fed a control low-fat diet, highlighting a diet-dependent contribution of CTRP1 deficiency to age-related changes in renal structure and function.


Assuntos
Adipocinas/deficiência , Envelhecimento/metabolismo , Dieta Hiperlipídica/efeitos adversos , Nefropatias/etiologia , Rim/metabolismo , Obesidade/etiologia , Adipocinas/genética , Fatores Etários , Envelhecimento/genética , Envelhecimento/patologia , Animais , Quimiocina CCL17/sangue , Feminino , Regulação da Expressão Gênica , Genótipo , Hipertrofia , Rim/ultraestrutura , Nefropatias/genética , Nefropatias/metabolismo , Nefropatias/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , Inibidor Tecidual de Metaloproteinase-1/sangue
15.
Biomed Pharmacother ; 133: 111061, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33378964

RESUMO

QiDiTangShen granules (QDTS), a traditional Chinese herbal medicine, have been used in clinical practice for treating diabetic kidney disease for several years. In our previous study, we have demonstrated that QDTS displayed good efficacy on reducing proteinuria in mice with diabetic nephropathy (DN). However, the exact mechanism by which QDTS exerts its reno-protection remains largely unknown. To ascertain whether QDTS could target the gut microbiota-bile acid axis, the db/db mice were adopted as a mouse model of DN. After a 12-week of treatment, we found that QDTS significantly reduced urinary albumin excretion (UAE), and attenuated the pathological injuries of kidney in the db/db mice, while the body weight and blood glucose levels of those mice were not affected. In addition, we found that QDTS significantly altered the gut microbiota composition, and decreased serum levels of total bile acid (TBA) and BA profiles such as ß-muricholic acid (ß-MCA), taurocholic acid (TCA), tauro ß-muricholic acid (Tß-MCA) and deoxycholic acid (DCA). These BAs are associated with the activation of farnesoid X receptor (FXR), which is highly expressed in kidney. However, there was no significant difference between QDTS-treated and -untreated db/db mice regarding the renal expression of FXR, indicating that other mechanisms may be involved. Conclusively, our study revealed that QDTS significantly alleviated renal injuries in mice with DN. The gut microbiota-bile acid axis may be an important target for the reno-protection of QDTS in DN, but the specific mechanism merits further study.


Assuntos
Ácidos e Sais Biliares/sangue , Nefropatias Diabéticas/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Rim/efeitos dos fármacos , Animais , Biomarcadores/sangue , Nefropatias Diabéticas/sangue , Nefropatias Diabéticas/microbiologia , Nefropatias Diabéticas/patologia , Modelos Animais de Doenças , Disbiose , Fezes/microbiologia , Intestinos/microbiologia , Intestinos/patologia , Rim/metabolismo , Rim/ultraestrutura , Masculino , Proteinúria/sangue , Proteinúria/microbiologia , Proteinúria/prevenção & controle
16.
J Morphol ; 282(2): 262-277, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33320355

RESUMO

We studied seasonal variation of the secretory granules in the epithelial cells of the sexual segment of the kidney (SSK) during the annual sexual cycle in the lizard, Eutropis carinata using light and electron microscopy in correlation with measurements of androgen levels. During the breeding phase, the epithelium of the SSK consists of simple columnar cells with basal nuclei. The cytoplasm contains numerous eosinophilic secretory protein and carbohydrate granules, but lacks glycosaminoglycans. These secretory granules develop during the regenerative phase when the circulating testosterone level increase. During the breeding phase, when the circulating testosterone levels are high, three types of secretory granules can be differentiated in the cytoplasm based on size and opacity; electron translucent type I, electron dense type II, and biphasic type III granules. Type II granules are found at various stages of maturity and degeneration/utilization. All types of secretory granules are released through an apocrine process. Microvilli and tight junctions are prominent at the apical portion of the cell. The cytoplasm contains, Golgi complexes, an abundant network of rough endoplasmic reticulum, numerous tubular mitochondria, condensing, mucus filled and empty vacuoles. Intercellular canaliculi are narrow and indistinct during the regenerative and breeding phases, respectively. During the regressed phase, when the circulating testosterone levels are lowest, the cells are found regressed with wide intercellular canaliculi and devoid of secretory granules. Then the cytoplasm contains a few round mitochondria, Golgi and scanty endoplasmic reticulum.


Assuntos
Rim/ultraestrutura , Lagartos/anatomia & histologia , Estações do Ano , Animais , Cruzamento , Retículo Endoplasmático/ultraestrutura , Células Epiteliais/ultraestrutura , Epitélio/ultraestrutura , Feminino , Hormônios/metabolismo , Masculino , Mitocôndrias/ultraestrutura
17.
PLoS One ; 15(12): e0244796, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33382808

RESUMO

Tiny membrane-enclosed cellular fragments that can mediate interactions between cells and organisms have recently become a subject of increasing attention. In this work the mechanism of formation of cell membrane nanovesicles (CNVs) was studied experimentally and theoretically. CNVs were isolated by centrifugation and washing of blood cells and observed by optical microscopy and scanning electron microscopy. The shape of the biological membrane in the budding process, as observed in phospholipid vesicles, in erythrocytes and in CNVs, was described by an unifying model. Taking the mean curvature h and the curvature deviator d of the membrane surface as the relevant parameters, the shape and the distribution of membrane constituents were determined theoretically by minimization of membrane free energy. Considering these results and previous results on vesiculation of red blood cells it was interpreted that the budding processes may lead to formation of different types of CNVs as regards the compartment (exo/endovesicles), shape (spherical/tubular/torocytic) and composition (enriched/depleted in particular kinds of molecules). It was concluded that the specificity of pinched off nanovesicles derives from the shape of the membrane constituents and not primarily from their chemical identity, which explains evidences on great heterogeneity of isolated extracellular vesicles with respect to composition.


Assuntos
Membrana Celular/ultraestrutura , Vesículas Extracelulares/ultraestrutura , Animais , Apoptose/fisiologia , Linhagem Celular , Cães , Membrana Eritrocítica/ultraestrutura , Rim/citologia , Rim/ultraestrutura , Microscopia Eletrônica de Varredura , Modelos Biológicos
18.
BMC Nephrol ; 21(1): 504, 2020 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-33234164

RESUMO

BACKGROUND: Since the Coronavirus Disease 2019 (COVID-19) outbreak, there is accumulating data on the clinical characteristics, treatment strategies and prognosis of COVID-19 in patients with concurrent renal disease. Postmortem investigations reveal renal involvement in COVID-19, and most recently, several biopsy researches reveal that acute tubular injury, as well as glomerular nephropathy such as collapsing glomerulopathy were common histological findings. However, to our best knowledge, there is limited data regarding IgA nephropathy in the setting of COVID-19. CASE PRESENTATION: In the present case, we report a 65-year old Chinese woman who presented with dark-colored urine, worsening proteinuria and decreased renal function after COVID-19 infection. She received a renal biopsy during COVID-19 infection. The renal biopsy revealed IgA nephropathy without any evidence for SARS-Cov-2. The findings suggest that the renal abnormalities were a consequence of exacerbation of this patient's underlying glomerular disease after COVID-19 infection. After a regimen of 3-day course of glucocorticoid and angiotensin II receptor blocker therapy, the patient recovered and remained stable upon follow-up. CONCLUSIONS: It is important to consider the underlying glomerular disease exacerbation as well as virus induced injury when dealing with renal abnormalities in patients with COVID-19. A kidney biopsy may be indicated to exclude a rapidly progressive glomerular disease.


Assuntos
COVID-19/diagnóstico por imagem , Glomerulonefrite por IGA/patologia , Rim/patologia , Pulmão/diagnóstico por imagem , Idoso , Antagonistas de Receptores de Angiotensina/uso terapêutico , COVID-19/complicações , COVID-19/diagnóstico , COVID-19/fisiopatologia , Teste de Ácido Nucleico para COVID-19 , Progressão da Doença , Feminino , Taxa de Filtração Glomerular , Glomerulonefrite por IGA/complicações , Glomerulonefrite por IGA/metabolismo , Glomerulonefrite por IGA/fisiopatologia , Glucocorticoides/uso terapêutico , Hematúria/fisiopatologia , Humanos , Rim/ultraestrutura , Rim/virologia , Microscopia Eletrônica , Proteinúria/fisiopatologia , Recuperação de Função Fisiológica
19.
Nutrients ; 12(11)2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-33120983

RESUMO

Maintaining tight junction (TJ) integrity is important for epithelial cell barriers. Previously, the enhancement of TJ integrity, induced by citrus-derived flavonoids, naringin (NRG) and hesperidin (HSD), was demonstrated, but the effects of their aglycones naringenin (NAR) and hesperetin (HST), and the mechanisms, have not been systematically investigated. Here we compared three series of flavonoids related to NAR, HST, quercetin (QUE) and their glycosides with the Madin-Darby canine kidney (MDCK) II cell monolayers. The effect of flavonoids on the protein expression level of claudin (CLD)-2 and its subcellular localization were investigated. NAR, NRG, and HSD increased the CLD-2 localization at the TJ compartment, and its protein expression level. QUE and HST showed TJ-mitigating activity. Narirutin (NRT), neohesperidin (NHD) and rutin (RUT) did not affect the TJ. In addition, NAR and QUE induced an increase or decrease of the transepithelial electrical resistance (TEER) values of the MDCK II monolayers. Two known signaling pathways, phosphatidyl-inositol-3 kinase (PI3K) and 5'-AMP-activated protein kinase (AMPK), were further compared with NAR. Two-dimensional polyacrylamide electrophoresis (2D PAGE) analysis of whole-cell proteins treated with NAR, AICA-riboside (AMPK activator) and LY294002 (PI3K inhibitor) showed in both a distinct pattern. This suggests the target of NAR's CLD-2 or zonula occludens-1 (ZO-1) modulation was unique.


Assuntos
Células Epiteliais/ultraestrutura , Flavanonas/farmacologia , Quercetina/farmacologia , Junções Íntimas/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Claudina-2/análise , Claudina-2/metabolismo , Cães , Células Epiteliais/efeitos dos fármacos , Rim/ultraestrutura , Células Madin Darby de Rim Canino , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Junções Íntimas/fisiologia , Junções Íntimas/ultraestrutura , Proteína da Zônula de Oclusão-1/metabolismo
20.
Sci Rep ; 10(1): 17572, 2020 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-33067578

RESUMO

Although gold-standard histological assessment is subjective it remains central to diagnosis and clinical trial protocols and is crucial for the evaluation of any preclinical disease model. Objectivity and reproducibility are enhanced by quantitative analysis of histological images but current methods require application-specific algorithm training and fail to extract understanding from the histological context of observable features. We reinterpret histopathological images as disease landscapes to describe a generalisable framework defining topographic relationships in tissue using geoscience approaches. The framework requires no user-dependent training to operate on all image datasets in a classifier-agnostic manner but is adaptable and scalable, able to quantify occult abnormalities, derive mechanistic insights, and define a new feature class for machine-learning diagnostic classification. We demonstrate application to inflammatory, fibrotic and neoplastic disease in multiple organs, including the detection and quantification of occult lobular enlargement in the liver secondary to hilar obstruction. We anticipate this approach will provide a robust class of histological data for trial stratification or endpoints, provide quantitative endorsement of experimental models of disease, and could be incorporated within advanced approaches to clinical diagnostic pathology.


Assuntos
Ciências da Terra/métodos , Técnicas Histológicas , Processamento de Imagem Assistida por Computador/métodos , Patologia Clínica/métodos , Animais , Modelos Animais de Doenças , Humanos , Rim/ultraestrutura , Fígado/ultraestrutura , Hepatopatias/patologia , Aprendizado de Máquina , Camundongos , Especificidade de Órgãos , Pâncreas/ultraestrutura , Reprodutibilidade dos Testes , Software , Doenças da Glândula Tireoide/patologia , Glândula Tireoide/ultraestrutura
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