RESUMO
Dromedary camels can survive and reproduce in desert areas. The unique anatomical structure of the kidney enables the camel to prevent water loss. The present study aimed to investigate the ultrastructure of the peroxisomes in the normal kidney of the adult dromedary camel. Tissue samples were taken from the cortex and outer medulla of the kidney of eight camels. The samples were then processed for histological and ultrastructural investigations. The epithelial cells of the proximal tubules displayed peroxisomes with varying sizes and shapes. The peroxisomes were observed in either dispersed or clustered arrangement. Each peroxisome exhibited a homogenous matrix enveloped by a single membrane. Several peroxisomes exhibited one or more dark marginal plates that were always strongly associated with the smooth endoplasmic reticulum. The intensity of the peroxisomal matrix differed significantly, either within the same cell or across different cells. The intensity was light or dark, with a few peroxisomes presenting a similar intensity to that of the mitochondria. Some peroxisomes contained nucleoids within their matrix. The peroxisomes in the first and second sections of proximal convoluted tubules were scattered and primarily located in the region between the microvilli and the underlying mitochondria. The peroxisomes in the third region were abundant and frequently aggregated in clusters throughout the cytoplasm. In the fourth region, the number of peroxisomes was low. The proximal straight tubule had a limited quantity of peroxisomes. In conclusion, peroxisomes in the proximal tubule in kidney of normal dromedary camel were similar in shape and size to other mammals; however, heterogeneity exists as a result of differences in species-specific peroxisomal proteins. Peroxisomes are suggested to be a major source of metabolic energy and act as hydrogen peroxide (H2O2) scavengers, resulting in the release of water and oxygen.
Assuntos
Camelus , Rim , Peroxissomos , Animais , Camelus/anatomia & histologia , Camelus/fisiologia , Peroxissomos/ultraestrutura , Peroxissomos/metabolismo , Rim/ultraestrutura , Rim/anatomia & histologia , Microscopia Eletrônica de Transmissão/veterinária , Masculino , Túbulos Renais Proximais/ultraestrutura , Túbulos Renais Proximais/anatomia & histologiaRESUMO
SUMMARY: Etoposide is an effective antimitotic and antineoplastic agent used to treat various human malignancies. In the present study, Etoposide was injected intraperitoneally into the rats at 1 mg/kg/day for 52 days (52 doses). The control animals received physiological saline (0.5 ml) intraperitoneally daily for 52 doses. The body weight of etoposide-treated rats was significantly reduced compared to control rats. Lipid peroxidation demonstrated an insignificant rise in hepatic tissue, a non-significant decline in renal tissue, and a significant reduction in cardiac tissue. The levels of GSH in hepatic and renal tissue were found to be non-significantly increased but significantly increased in cardiac tissue compared to controls. GR activity was found to be considerably decreased in the treated group. G-S-T levels increased significantly in all treated group. Etoposide injections caused a non-significant change in the GPX level of hepatic tissue, whereas renal and cardiac tissues showed a significant increase. The activity of CAT in hepatic tissue was significantly increased, while CAT activity in renal tissue showed a non-significant decrease, whereas in cardiac tissue, significantly lower levels were observed than in control group. The level of CYTp450 in hepatic and cardiac tissues showed a significant increase; however, renal tissue showed non-significant depletion, whereas CYTb5 in hepatic, renal, and cardiac tissues was significantly lower than controls. The protein content in the hepatic tissue was not significantly increased, whereas the total protein in the renal and cardiac tissues was increased significantly. The research finding is indicative of detoxification activity in the etoposide model.
El etopósido es un agente antimitótico y antineoplásico eficaz que se utiliza para tratar diversas neoplasias malignas humanas. En el presente estudio, se inyectó etopósido por vía intraperitoneal a las ratas a razón de 1 mg/kg/día durante 52 días (52 dosis). Los animales control recibieron solución salina fisiológica (0,5 ml) por vía intraperitoneal diariamente por 52 dosis. El peso corporal de las ratas tratadas con etopósido se redujo significativamente en comparación con las ratas del grupo control. La peroxidación lipídica demostró un aumento insignificante del tejido hepático, una disminución no significativa del tejido renal y una reducción significativa del tejido cardíaco. Se encontró que los niveles de GSH en el tejido hepático y renal no aumentaron significativamente, pero sí aumentaron significativamente en el tejido cardíaco en comparación con los controles. Se encontró que la actividad de GR disminuyó considerablemente en el grupo tratado. Los niveles de G-S-T aumentaron significativamente en todos los grupos tratados. Las inyecciones de etopósido provocaron un cambio no significativo en el nivel de GPX del tejido hepático, mientras que los tejidos renal y cardíaco mostraron un aumento significativo. La actividad de CAT en el tejido hepático aumentó significativamente, mientras que la actividad de CAT en el tejido renal mostró una disminución no significativa, mientras que en el tejido cardíaco se observaron niveles significativamente más bajos que en el grupo de control. El nivel de CYTp450 en los tejidos hepático y cardíaco mostró un aumento significativo; sin embargo, el tejido renal mostró un agotamiento no significativo, mientras que CYTb5 en los tejidos hepático, renal y cardíaco fue significativamente menor que los controles. El contenido de proteínas en el tejido hepático no aumentó significativamente, mientras que la proteína total en los tejidos renal y cardíaco aumentó significativamente. El hallazgo de la investigación es indicativo de la actividad de desintoxicación en el modelo de etopósido.
Assuntos
Animais , Masculino , Ratos , Etoposídeo/administração & dosagem , Coração/efeitos dos fármacos , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Antioxidantes/administração & dosagem , Tamanho do Órgão/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Peroxidação de Lipídeos , Citocromos b5/análise , Ratos Wistar , Sistema Enzimático do Citocromo P-450/análise , Etoposídeo/farmacologia , Rim/ultraestrutura , Fígado/ultraestrutura , Microscopia , Miocárdio/ultraestrutura , Antineoplásicos Fitogênicos , Antioxidantes/farmacologiaRESUMO
In this clinical case report, we present a rare subtype of amyloidosis, apolipoprotein CII (apo CII), which was diagnosed through a renal biopsy and subsequently confirmed by identifying the p.K41T mutation via germline DNA sequencing. Upon reviewing the literature, five patients exhibiting identical mutation were identified via renal biopsy, while an additional patient was diagnosed through biopsies of the fat pad and bone marrow. Notably, our patient is the youngest recorded case. We pioneered the application of immunofluorescence and immunogold electron microscopy techniques for apo CII evaluation. Our report provides a detailed description of this case, supplemented by an extensive review encompassing apo CII, documented instances of apo CII amyloidosis with renal or systemic involvement, and potential underlying mechanisms.
Assuntos
Amiloidose , Humanos , Amiloidose/patologia , Masculino , Rim/patologia , Rim/ultraestrutura , Nefropatias/patologia , Amiloide , Feminino , Pessoa de Meia-Idade , Apolipoproteína C-IIRESUMO
BACKGROUNDS: Chronic kidney disease (CKD) is a global public health problem. All progressive chronic kidney disease (CKD) is characterized by tubulointerstitial fibrosis. Exposure to high concentrations of carbon tetrachloride (including vapor) can destroy the kidneys. Autophagy played an important role in maintaining the homeostasis of organs. Impaired autophagy was frequently associated with renal damage and fibrosis. Recent data suggests that metformin protects against a variety of kidney disorders. AIM: To investigate the protective role of metformin on carbon tetrachloride induced renal damage via autophagy pathway. MATERIALS AND METHODS: Forty adult male albino rats were divided into four equal groups (10 rats, each); Group 1: control group. Group 2: olive oil group received olive oil 1.5 mg/kg twice weekly S.C for 12 weeks. Group 3: The ccl4 group, the rats were received ccl4 1.5 mg/kg twice weekly S.C for 12 weeks. Group 4: CCL4 and Metformin group received concomitant treatment of CCL4, 1.5 mg/kg twice weekly S.C and 100 mg/kg/day Metformin orally for 12 weeks. After sacrifice, kidneys were taken from all animal groups and processed for light and electron microscopy, immunological studies and biochemical tests. Statistical analysis was done. RESULTS: Administration of ccl4 resulted in histopathological changes in the kidney tissue in the form of areas of tissue destruction, inflammatory cell infiltration, congestion and fibrosis. Ultrastructurally, irregular thickening of GBM was observed. Improvement was noticed with concomitant treatment of ccl4 with metformin. CONCLUSION: Metformin administration can modulate histological and biochemical effects in the renal tissue induced by of ccl4.
Assuntos
Autofagia , Tetracloreto de Carbono , Fibrose , Rim , Metformina , Animais , Metformina/farmacologia , Masculino , Autofagia/efeitos dos fármacos , Ratos , Tetracloreto de Carbono/toxicidade , Rim/patologia , Rim/efeitos dos fármacos , Rim/ultraestrutura , Insuficiência Renal Crônica/patologia , Insuficiência Renal Crônica/tratamento farmacológicoRESUMO
Pluripotent stem cell-derived kidney organoids hold great promise as a potential auxiliary transplant tissue for individuals with end-stage renal disease and as a platform for studying kidney diseases and drug discovery. To establish accurate models, it is crucial to thoroughly characterize the morphological features and maturation stages of the cellular components within these organoids. Nephrons, the functional units of the kidney, possess distinct morphological structures that directly correlate with their specific functions. High spatial resolution imaging emerges as a powerful technique for capturing ultrastructural details that may go unnoticed with other methods such as immunofluorescent imaging and scRNA sequencing. In our study, we have applied software capable of seamlessly stitching virtual slides generated from electron microscopy, resulting in high-definition overviews of tissue slides. With this technology, we can comprehensively characterize the development and maturation of kidney organoids when transplanted under the renal capsule of mice. These organoids exhibit advanced ultrastructural developments upon transplantation, including the formation of the filtration barrier in the renal corpuscle, the presence of microvilli in the proximal tubule, and various types of cell sub-segmentation in the connecting tubule similarly to those seen in the adult kidney. Such ultrastructural characterization provides invaluable insights into the structural development and functional morphology of nephron segments within kidney organoids and how to advance them by interventions such as a transplantation. Research Highlights High-resolution imaging is crucial to determine morphological maturation of hiPSC-derived kidney organoids. Upon transplantation, refined ultrastructural development of nephron segments was observed, such as the development of the glomerular filtration barrier.
Assuntos
Células-Tronco Pluripotentes Induzidas , Células-Tronco Pluripotentes , Animais , Camundongos , Diferenciação Celular , Néfrons/metabolismo , Rim/ultraestruturaRESUMO
SUMMARY: Diabetic nephropathy (DN) is the most common complication of diabetes. Several studies have been done in a trial to protect against this problem at the ultrastructure level. This study investigates the protective effect of oral administration of Acacia senegal (AS) against the development of DN. Sixty male albino rats were randomly divided into six groups: control, Acacia senegal control, Diabetic untreated, diabetic insulin-treated, Diabetic AS treated, and Diabetic insulin and AS combined treated groups. Plasma glucose, HbA1c, serum Albumin, creatinine, urine creatinine was measured using specific kits. Determinations of creatinine clearance and blood pressure were done. The renal tissues of both kidneys were prepared to investigate under both light (LM) and electron microscope (EM). Ultrastructure examination of renal rats tissue of diabetic untreated rats showed the destruction of the glomerular basement membrane and endothelial cells together with hemorrhage in glomerular capsules (Bowman's capsules). On the other side, both LM and EM revealed improving the endothelial cells and the other glomerular capsules structures, especially with the combined treated group, which confirmed the improvement of the biochemical investigation in the study. In conclusion, from the present study, using the oral AS together with SC insulin could be protected against the development of DN.
RESUMEN: La nefropatía diabética (ND) es la complicación más común de la diabetes. Se han realizado varios estudios de ensayo para abordar esta dificultad a nivel de ultraestructura. Este estudio investiga el efecto protector de la administración oral de Acacia senegal (AS) contra el desarrollo de la ND. Se dividieron sesenta ratas albinas machos aleatoriamente en seis grupos: control, control de Acacia senegal, diabéticos no tratados, diabéticos tratados con insulina, diabéticos tratados con AS y grupos tratados con compuesto de insulina diabética + AS. Se midieron utilizando kits específicos, glucosa plasmática, HbA1c, albúmina sérica, creatinina en sangre y en orina. Se registraron la creatinina y la presión arterial. Los tejidos renales de ambos riñones se prepararon para investigar tanto con microscopio óptico (MO) como electrónico (ME). El examen de la ultraestructura del tejido renal de ratas diabéticas no tratadas mostró la destrucción de la membrana basal glomerular y las células endoteliales junto con hemorragia en las cápsulas glomerulares (cápsulas de Bowman). Por otro lado, tanto MO como ME revelaron una mejora de las células endoteliales y las estructuras capsulares glomerulares, en el grupo tratado con el compuesto, lo que confirmó la mejora de la investigación bioquímica. En conclusión, el uso de AS oral en combinación con insulina podría proteger contra el desarrollo de ND.
Assuntos
Animais , Ratos , Nefropatias Diabéticas/prevenção & controle , Acacia , Goma Arábica/administração & dosagem , Rim/efeitos dos fármacos , Microscopia Eletrônica , Biomarcadores , Administração Oral , Ratos Sprague-Dawley , Modelos Animais de Doenças , Rim/ultraestruturaRESUMO
The kidney of fish contains numerous nephrons, each of which is divided into the renal corpuscle and renal tubules. This glomerular structure is the filtration unit of the nephron and is important for the kidney function, but it has been reported that the renal corpuscle was lost in at least four independent linages of fish (i.e., aglomerular kidney). In this study, the authors newly described renal structures for three species by histological and ultrastructural observations: two aglomerular kidneys from a seahorse Hippocampus barbouri and a toadfish Allenbatrachus grunniens and a glomerular kidney from a snake eel Pisodonophis boro. The renal development of H. barbouri was also described during 1-35 days after birth. In all species tested, the anterior kidney was comprised of haematopoietic tissues and a few renal tubules, whereas the posterior kidney contained more renal tubules. Although the glomerular structure was present in P. boro, light microscopic observations identified no glomeruli in the kidney of H. barbouri and A. grunniens. Ultrastructurally, abundant deep basal infoldings with mitochondria in the renal tubules were observed in A. grunniens compared to H. barbouri and P. boro, suggesting the possible role of basal infoldings in maintaining the osmotic balance. By integrating the results from the three species and comprehensive literature search, the authors further showed that 56 species have been reported to be aglomerular, and that the aglomerular kidney has evolved at least eight times in bony fishes.
Assuntos
Batracoidiformes , Smegmamorpha , Animais , Rim/ultraestrutura , Glomérulos Renais/ultraestrutura , Túbulos Renais , Néfrons/ultraestruturaRESUMO
The onset of coronavirus disease (COVID-19) as a pandemic infection, has led to increasing insights on its pathophysiology and clinical features being revealed, such as a noticeable kidney involvement. In this study, we describe the histopathological, immunofluorescence, and ultrastructural features of biopsy-proven kidney injury observed in a series of SARS-CoV-2 positive cases in our institution from April 2020 to November 2021. We retrieved and retrospectively reviewed nine cases (two pediatric and seven adults) that experienced nephrotic syndrome (six cases), acute kidney injury (two cases), and a clinically silent microhematuria and leukocyturia. Kidney biopsies were investigated by means of light microscopy, direct immunofluorescence, and electron microscopy. The primary diagnoses were minimal change disease (four cases), acute tubular necrosis (two cases), collapsing glomerulopathy (two cases), and C3 glomerulopathy (one case). None of the cases showed viral or viral-like particles on ultrastructural analysis. Novel and specific histologic features on kidney biopsy related to SARS-CoV-2 infection have been gradually disclosed and reported, harboring relevant clinical and therapeutic implications. Recognizing and properly diagnosing renal involvement in patients experiencing COVID-19 could be challenging (due to the lack of direct proof of viral infection, e.g., viral particles) and requires a proper integration of clinical and pathological data.
Assuntos
COVID-19/complicações , Nefropatias/complicações , Nefropatias/virologia , Rim/lesões , Rim/virologia , Adolescente , Idoso , Idoso de 80 Anos ou mais , Biópsia , COVID-19/patologia , COVID-19/virologia , Feminino , Humanos , Itália , Rim/patologia , Rim/ultraestrutura , Nefropatias/patologia , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
The present study explored the protective effect of exogenous hydrogen sulfide (H2S) on lipopolysaccharide (LPS)induced acute kidney injury (AKI) and the underlying mechanisms. To establish an AKI injury mouse model, LPS (10 mg/kg) was intraperitoneally injected into mice pretreated with 0.8 mg/kg sodium hydrosulfide hydrate (NaHS), an H2S donor. The mouse survival rate and the degree of kidney injury were examined. To construct a cell damage model, HK2 cells were pretreated with different concentrations (0.1, 0.3 and 0.5 mM) of NaHS, and then the cells were stimulated with LPS (1 µg/ml). The cell viability, autophagy, apoptosis levels and the release of inflammatory factors were examined in mouse kidney tissue and HK2 renal tubular epithelial cells. It was found that pretreatment with NaHS significantly improved the survival rate of septic AKI mice, and reduced the renal damage, release of inflammatory factors and apoptosis. In HK2 cells, NaHS protected cells from LPS caused damage via promoting autophagy and inhibiting apoptosis and the release of inflammatory factors. In order to clarify the relationship between autophagy and apoptosis and inflammatory factors, this study used 3methyladenine (3MA) to inhibit autophagy. The results revealed that 3MA eliminated the protective effect of NaHS in HK2 cells and AKI mice. Overall, NaHS can protect from LPSinduced AKI by promoting autophagy and inhibiting apoptosis and the release of inflammatory factors.
Assuntos
Injúria Renal Aguda/prevenção & controle , Autofagia/efeitos dos fármacos , Sulfeto de Hidrogênio/farmacologia , Rim/efeitos dos fármacos , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/metabolismo , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Sulfeto de Hidrogênio/metabolismo , Rim/patologia , Rim/ultraestrutura , Lipopolissacarídeos , Masculino , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Substâncias Protetoras/metabolismo , Substâncias Protetoras/farmacologia , Sulfetos/metabolismo , Sulfetos/farmacologiaRESUMO
Tau is a cytoskeletal protein that is expressed mainly in neurons and is involved in several cellular processes, such as microtubule stabilization, axonal maintenance, and transport. Altered tau metabolism is related to different tauopathies being the most important Alzheimer's disease where aberrant hyperphosphorylated and aggregated tau is found in the central nervous system. Here, we have analyzed that function in kidney by using tau knockout mice generated by integrating GFP-encoding cDNA into exon 1 of MAPT (here referred to as TauGFP/GFP). IVIS Lumina from PerkinElmer demonstrated GFP expression in the kidney. We then demonstrated by qPCR that the main tau isoform in the kidney is Tau4R. The GFP reporter allowed us to demonstrate that tau is found in the glomeruli of the renal cortex, and specifically in podocytes. This was further confirmed by immunohistochemistry. TauGFP/GFP mice present a podocyte cytoskeleton more dynamic as they contain higher levels of detyrosinated tubulin than wild-type mice. In addition, transmission electron microscopy studies demonstrated glomerular damage with a decrease in urinary creatinine. Our results prove that tau has an important role in kidney metabolism under normal physiological conditions.
Assuntos
Rim/metabolismo , Microtúbulos/metabolismo , Podócitos/metabolismo , Tauopatias/metabolismo , Proteínas tau/metabolismo , Animais , Citoesqueleto/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Rim/citologia , Rim/ultraestrutura , Glomérulos Renais/metabolismo , Glomérulos Renais/ultraestrutura , Camundongos da Linhagem 129 , Camundongos Knockout , Camundongos Transgênicos , Microscopia Confocal , Microscopia Imunoeletrônica , Tauopatias/genética , Proteínas tau/genéticaRESUMO
BACKGROUND: Gitelman syndrome is the most frequent hereditary salt-losing tubulopathy characterized by hypokalemic alkalosis and hypomagnesemia. Gitelman syndrome is caused by biallelic pathogenic variants in SLC12A3, encoding the Na+-Cl- cotransporter (NCC) expressed in the distal convoluted tubule. Pathogenic variants of CLCNKB, HNF1B, FXYD2, or KCNJ10 may result in the same renal phenotype of Gitelman syndrome, as they can lead to reduced NCC activity. For approximately 10 percent of patients with a Gitelman syndrome phenotype, the genotype is unknown. METHODS: We identified mitochondrial DNA (mtDNA) variants in three families with Gitelman-like electrolyte abnormalities, then investigated 156 families for variants in MT-TI and MT-TF, which encode the transfer RNAs for phenylalanine and isoleucine. Mitochondrial respiratory chain function was assessed in patient fibroblasts. Mitochondrial dysfunction was induced in NCC-expressing HEK293 cells to assess the effect on thiazide-sensitive 22Na+ transport. RESULTS: Genetic investigations revealed four mtDNA variants in 13 families: m.591C>T (n=7), m.616T>C (n=1), m.643A>G (n=1) (all in MT-TF), and m.4291T>C (n=4, in MT-TI). Variants were near homoplasmic in affected individuals. All variants were classified as pathogenic, except for m.643A>G, which was classified as a variant of uncertain significance. Importantly, affected members of six families with an MT-TF variant additionally suffered from progressive chronic kidney disease. Dysfunction of oxidative phosphorylation complex IV and reduced maximal mitochondrial respiratory capacity were found in patient fibroblasts. In vitro pharmacological inhibition of complex IV, mimicking the effect of the mtDNA variants, inhibited NCC phosphorylation and NCC-mediated sodium uptake. CONCLUSION: Pathogenic mtDNA variants in MT-TF and MT-TI can cause a Gitelman-like syndrome. Genetic investigation of mtDNA should be considered in patients with unexplained Gitelman syndrome-like tubulopathies.
Assuntos
DNA Mitocondrial/genética , Síndrome de Gitelman/genética , Mutação , Adolescente , Adulto , Idoso , Sequência de Bases , Criança , Pré-Escolar , Feminino , Genótipo , Síndrome de Gitelman/metabolismo , Síndrome de Gitelman/patologia , Células HEK293 , Humanos , Lactente , Rim/metabolismo , Rim/ultraestrutura , Masculino , Pessoa de Meia-Idade , Mitocôndrias/metabolismo , Modelos Biológicos , Conformação de Ácido Nucleico , Linhagem , Fenótipo , Polimorfismo de Nucleotídeo Único , RNA de Transferência de Isoleucina/química , RNA de Transferência de Isoleucina/genética , RNA de Transferência de Fenilalanina/química , RNA de Transferência de Fenilalanina/genética , Membro 3 da Família 12 de Carreador de Soluto/genética , Adulto JovemRESUMO
BACKGROUND: Low-vacuum scanning electron microscopy (LV-SEM) is applied to diagnostic renal pathology. METHODS: To demonstrate the usefulness of LV-SEM and to clarify the optimal conditions of pathology samples, we investigated the alterations of glomerular basement membrane (GBM) and podocytes in control and experimental active Heymann nephritis (AHN) rats by LV-SEM. RESULTS: On week 15 following induction of AHN, spike formation on GBM with diffuse deposition of IgG and C3 developed. Using LV-SEM, diffuse crater-like protrusions were clearly noted three-dimensionally (3D) on surface of GBM in the same specimens of light microscopy (LM) and immunofluorescence (IF) studies only after removal coverslips or further adding periodic acid-silver methenamine (PAM) staining. These 3D ultrastructural findings of GBM surface could be detected in PAM-stained specimens by LV-SEM, although true GBM surface findings could not be obtained in acellular glomeruli, because some subepithelial deposits remained on surface of GBM. Adequate thickness was 1.5-5 µm for 10% formalin-fixed paraffin-embedded (FFPE) and 5-10 µm for the unfixed frozen sections. The foot processes and their effacement of podocytes could be observed by LV-SEM using 10%FFPE specimens with platinum blue (Pt-blue) staining or double staining of PAM and Pt-blue. These findings were obtained more large areas in 2.5% glutaraldehyde-fixed paraffin-embedded (2.5%GFPE) specimens. CONCLUSION: Our findings suggest that LV-SEM is a useful assessment tool for evaluating the alterations of GBM and podocytes in renal pathology using routine LM and IF specimens, as well as 2.5%GFPE specimens.
Assuntos
Membrana Basal Glomerular , Podócitos , Animais , Membrana Basal Glomerular/patologia , Humanos , Rim/ultraestrutura , Microscopia Eletrônica de Varredura , Podócitos/patologia , Ratos , VácuoRESUMO
In the context of transplantation, complement activation is associated with poor prognosis and outcome. While complement activation in antibody-mediated rejection is well-known, less is known about complement activation in acute T cell-mediated rejection (TCMR). There is increasing evidence that complement contributes to the clearance of apoptotic debris and tissue repair. In this regard, we have analysed published human kidney biopsy transcriptome data clearly showing upregulated expression of complement factors in TCMR. To clarify whether and how the complement system is activated early during acute TCMR, experimental syngeneic and allogeneic renal transplantations were performed. Using an allogeneic rat renal transplant model, we also observed upregulation of complement factors in TCMR in contrast to healthy kidneys and isograft controls. While staining for C4d was positive, staining with a C3d antibody showed no C3d deposition. FACS analysis of blood showed the absence of alloantibodies that could have explained the C4d deposition. Gene expression pathway analysis showed upregulation of pro-apoptotic factors in TCMR, and apoptotic endothelial cells were detected by ultrastructural analysis. Monocytes/macrophages were found to bind to and phagocytise these apoptotic cells. Therefore, we conclude that early C4d deposition in TCMR may be relevant to the clearance of apoptotic cells.
Assuntos
Apoptose , Complemento C4b/metabolismo , Transplante de Rim , Fragmentos de Peptídeos/metabolismo , Animais , Biópsia , Modelos Animais de Doenças , Regulação da Expressão Gênica , Rim/patologia , Rim/ultraestrutura , Masculino , Ratos Endogâmicos BN , Receptores de Morte Celular/metabolismo , Transdução de Sinais , Transcriptoma/genética , Transplante HomólogoRESUMO
Chemicals can induce nephrotoxicity, with damage to different segments of the nephron and deterioration of renal function. Nephrotoxicity due to exposure to a toxin such as carbon tetrachloride, sodium oxalate, or heavy metals is the most common cause of kidney injury. The current study aimed to evaluate the protective effects of Celastrus paniculatus seed extract against lead-acetate-induced nephrotoxicity by evaluating the histopathology, immunohistochemistry, ultrastructure, and phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway. Twenty-four rats were divided into four groups (n = 6 per group): group 1 contained normal animals and served as the control; group 2 received lead acetate (30 mg/kg body weight (b.w.)/day, oral); group 3 received lead acetate and the standard drug N-acetylcysteine (NAC, 200 mg/kg b.w./day, oral); and group 4 received lead acetate and the ethanolic extract of C. paniculatus seed (EECP; 800 mg/kg b.w./day, oral). Treatment was given for 28 consecutive days. The data were analyzed using one-way analysis of variance with SIGMA PLOT 13 using SYSTAT software followed by Newman-Keul's test for comparison between the groups. EECP ameliorated the adverse changes caused by lead acetate. PI3K and AKT messenger RNA (mRNA) levels were diminished in lead-acetate-treated rats. Treatment with EECP inhibited the occurrence of shrunken cells, the atrophy of glomeruli, and degenerative changes in renal tubules caused by lead acetate. Interestingly, the PI3K and AKT mRNA levels were significantly increased in EECP-treated animals. Our results clearly evidence for the first time that C. paniculatus seed extract inhibits lead-acetate-induced detrimental changes in kidneys by regulating PI3K/AKT signaling pathways.
Assuntos
Celastrus/química , Rim/efeitos dos fármacos , Rim/metabolismo , Compostos Organometálicos/efeitos adversos , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Animais , Biomarcadores , Feminino , Expressão Gênica , Imuno-Histoquímica , Rim/patologia , Rim/ultraestrutura , Fosfatidilinositol 3-Quinases/metabolismo , Extratos Vegetais/química , Substâncias Protetoras/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacosRESUMO
Renal tubulointerstitial fibrosis was a crucial pathological feature of diabetic nephropathy (DN), and renal tubular injury might associate with abnormal mitophagy. In this study, we investigated the effects and molecular mechanisms of AMPK agonist metformin on mitophagy and cellular injury in renal tubular cell under diabetic condition. The high fat diet (HFD) and streptozotocin (STZ)-induced type 2 diabetic mice model and HK-2 cells were used in this study. Metformin was administered in the drinking water (200 mg/kg/d) for 24 weeks. Renal tubulointerstitial lesions, oxidative stress and some indicators of mitophagy (e.g., LC3II, Pink1, and Parkin) were examined both in renal tissue and HK-2 cells. Additionally, compound C (an AMPK inhibitor) and Pink1 siRNA were applied to explore the molecular regulation mechanism of metformin on mitophagy. We found that the expression of p-AMPK, Pink1, Parkin, LC3II, and Atg5 in renal tissue of diabetic mice was decreased obviously. Metformin reduced the levels of serum creatinine, urine protein, and attenuated renal oxidative injury and fibrosis in HFD/STZ induced diabetic mice. In addition, Metformin reversed mitophagy dysfunction and the over-expression of NLRP3. In vitro pretreatment of HK-2 cells with AMPK inhibitor compound C or Pink1 siRNA negated the beneficial effects of metformin. Furthermore, we noted that metformin activated p-AMPK and promoted the translocation of Pink1 from the cytoplasm to mitochondria, then promoted the occurrence of mitophagy in HK-2 cells under HG/HFA ambience. Our results suggested for the first time that AMPK agonist metformin ameliorated renal oxidative stress and tubulointerstitial fibrosis in HFD/STZ-induced diabetic mice via activating mitophagy through a p-AMPK-Pink1-Parkin pathway.
Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Diabetes Mellitus Experimental/patologia , Dieta Hiperlipídica , Rim/patologia , Mitofagia , 8-Hidroxi-2'-Desoxiguanosina/metabolismo , Animais , Glicemia/metabolismo , Nitrogênio da Ureia Sanguínea , Linhagem Celular , Colágeno Tipo I/metabolismo , Creatinina/sangue , Diabetes Mellitus Experimental/sangue , Fibronectinas/metabolismo , Fibrose , Humanos , Interleucina-1beta/metabolismo , Rim/ultraestrutura , Metformina/farmacologia , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Mitofagia/efeitos dos fármacos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Proteínas Quinases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Estreptozocina , Ubiquitina-Proteína Ligases/metabolismoRESUMO
The current work aims to study the nephroprotective potential of naringin (NG), a flavanone derived from citrus fruits, in methotrexate (MTX)-induced renal toxicity. Thirty male rats were divided into five groups; control group (IP saline), MTX group (IP single dose, 20 mg/kg), and three groups co-treated with MTX and naringin (IP daily dose; 20, 40, and 80 mg/kg, respectively). Kidney tissues were used to investigate renal function, oxidative stress, lipid peroxidation, and caspase-3 activity. Biochemical cytokine analysis was performed in addition to ultrastructural examinations of kidney tissue. When compared to the MTX-treated rats, MTX+NG signiï¬cantly reduced the levels of urea, creatinine, MDA, NO, TNFα, IL-6, and caspase-3 activity. A significant increase in the levels of the antioxidant enzymes and GSH were also noted. Additionally, naringin ameliorated the apparent ultrastructural changes observed in the glomeruli and renal tubules of MTX-intoxicated rats. Noticeable structural improvements of glomerular lesions, proximal, and distal convoluted tubular epithelium were observed in MTX+NG treated animals, including podocytes with regular foot processes, perfectly organized filtration barrier, no signs of GBM thickening, organized brush border, and normal architecture of microvilli. Naringin (80 mg/kg) had the maximum amelioration effect. To the best of our knowledge, this is the first study to investigate the ultrastructural manifestations of naringin and/or MTX on the kidney of rats. Taken all, naringin has a potent therapeutic effect and can be used in adjuvant therapy to prevent MTX-induced nephrotoxicity. Nevertheless, the molecular mechanism underlying the nephroprotective capacity of naringin needs further investigation.
Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Flavanonas/farmacologia , Nefropatias/prevenção & controle , Rim/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Biomarcadores/metabolismo , Caspase 3/metabolismo , Modelos Animais de Doenças , Mediadores da Inflamação/metabolismo , Interleucina-6/metabolismo , Rim/metabolismo , Rim/ultraestrutura , Nefropatias/induzido quimicamente , Nefropatias/metabolismo , Nefropatias/patologia , Masculino , Metotrexato , Estresse Oxidativo/efeitos dos fármacos , Ratos , Fator de Necrose Tumoral alfa/metabolismoRESUMO
The kidney of Catla catla, chronically exposed to sub-lethal concentrations (0.24 µg/L and 0.41 µg/L) of cypermethrin revealed a significant elevation in the activity of antioxidants superoxide dismutase (SOD), catalase (CAT), glutathione-s-transferase (GST) and reduced glutathione (GSH) after 15 days, followed by a decline of up to 45 days. Lipid peroxidation (LPO) remained elevated throughout the exposure duration. Histology presented proliferated haematopoietic tissue, tubular and glomerular degeneration. The maximum increase in the mean degree of tissue change (DTC) was observed on the 45th day of treatment. Ultra-structure study depicted cytoplasmic vacuolation, fragmented RER, the proliferation of lysosomes, mitochondrial degeneration, and degenerative changes in the epithelial lining of renal tubules. Principal component analysis (PCA) of various biomarkers generated two components PCI (SOD, GST, GSH, LPO and DTC) and PCII (CAT). These findings suggest that long term exposure to cypermethrin can lead to various pathological alterations in the fish kidney which in turn might interfere with normal renal excretory mechanism.
Assuntos
Cyprinidae , Inseticidas/toxicidade , Rim/efeitos dos fármacos , Piretrinas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Catalase/metabolismo , Cyprinidae/metabolismo , Água Doce , Glutationa/metabolismo , Glutationa Transferase/metabolismo , Rim/metabolismo , Rim/patologia , Rim/ultraestrutura , Peroxidação de Lipídeos/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/metabolismoRESUMO
BACKGROUND: Focal and segmental glomerulosclerosis (FSGS) is a histologic pattern of injury that characterizes a wide spectrum of diseases. Many genetic causes have been identified in FSGS but even in families with comprehensive testing, a significant proportion remain unexplained. METHODS: In a family with adult-onset autosomal dominant FSGS, linkage analysis was performed in 11 family members followed by whole exome sequencing (WES) in 3 affected relatives to identify candidate genes. RESULTS: Pathogenic variants in known nephropathy genes were excluded. Subsequently, linkage analysis was performed and narrowed the disease gene(s) to within 3% of the genome. WES identified 5 heterozygous rare variants, which were sequenced in 11 relatives where DNA was available. Two of these variants, in LAMA2 and LOXL4, remained as candidates after segregation analysis and encode extracellular matrix proteins of the glomerulus. Renal biopsies showed classic segmental sclerosis/hyalinosis lesion on a background of mild mesangial hypercellularity. Examination of basement membranes with electron microscopy showed regions of dense mesangial matrix in one individual and wider glomerular basement membrane (GBM) thickness in two individuals compared to historic control averages. CONCLUSIONS: Based on our findings, we postulate that the additive effect of digenic inheritance of heterozygous variants in LAMA2 and LOXL4 leads to adult-onset FSGS. Limitations to our study includes the absence of functional characterization to support pathogenicity. Alternatively, identification of additional FSGS cases with suspected deleterious variants in LAMA2 and LOXL4 will provide more evidence for disease causality. Thus, our report will be of benefit to the renal community as sequencing in renal disease becomes more widespread.
Assuntos
Glomerulosclerose Segmentar e Focal/genética , Laminina/genética , Proteína-Lisina 6-Oxidase/genética , Idade de Início , Idoso , Membrana Basal/ultraestrutura , Transtornos Cromossômicos/genética , Feminino , Testes Genéticos , Heterozigoto , Humanos , Rim/ultraestrutura , Masculino , Pessoa de Meia-Idade , Mutação , Linhagem , Sequenciamento do ExomaRESUMO
An automatic decellularization device was developed to perfuse and decellularize male rats' kidneys using both sodium lauryl ether sulfate (SLES) and sodium dodecyl sulfate (SDS) and to compare their efficacy in kidney decellularization and post-transplantation angiogenesis. Kidneys were perfused with either 1% SDS solution for 4 h or 1% SLES solution for 6 h. The decellularized scaffolds were stained with hematoxylin and eosin, periodic acid Schiff, Masson's trichrome, and Alcian blue to determine cell removal and glycogen, collagen, and glycosaminoglycan contents, respectively. Moreover, scanning electron microscopy was performed to evaluate the cell removal and preservation of microarchitecture of both SDS and SLES scaffolds. Additionally, DNA quantification assay was applied for all groups in order to measure residual DNA in the scaffolds and normal kidney. In order to demonstrate biocompatibility of the decellularized scaffolds, human umbilical cord mesenchymal stromal/stem cells (hUC-MSCs) were seeded on the scaffolds. In addition, the allotransplantation was performed in back muscle and angiogenesis was evaluated. Complete cell removal in both SLES and SDS groups was observed in scanning electron microscopy and DNA quantification assays. Moreover, the extracellular matrix (ECM) architecture of rat kidney in the SLES group was significantly preserved better than the SDS group. The hUC-MSCs were successfully migrated from the cell culture plate surface into the SDS and SLES decellularized scaffolds. The formation of blood vessels was observed in the kidney in both SLES and SDS decellularized kidneys. The better preservation of ECM than SDS introduces SLES as the solvent of choice for kidney decellularization.
Assuntos
Matriz Extracelular Descelularizada/química , Rim/química , Polietilenoglicóis/química , Dodecilsulfato de Sódio/química , Alicerces Teciduais/química , Animais , Rim/citologia , Rim/ultraestrutura , Ratos , Ratos Sprague-Dawley , Transplante de Células-Tronco , Células-Tronco/citologia , Engenharia TecidualRESUMO
Gaia Pigino studies the molecular mechanisms and principles of self-organization in cilia using 3D cryo-EM.