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Several artificial intelligence (AI) systems have been developed for glomerular pathology analysis in clinical settings. However, the application of AI systems in nonclinical fields remains limited. In this study, we trained a convolutional neural network model, which is an AI algorithm, to classify the severity of Tensin 2 (TNS2)-deficient nephropathy into seven categories. A dataset consisting of 803 glomerular images was generated from kidney sections of TNS2-deficient and wild-type mice. Manual evaluations of the images were conducted to assess their glomerular injury scores. The trained AI achieved approximately 70% accuracy in predicting the glomerular injury score for TNS2-deficient nephropathy. However, the AI achieved approximately 100% accuracy when considering predictions within one score of the true label as correct. The AI's predicted mean score closely matched the true mean score. In conclusion, while the AI model may not replace human judgment entirely, it can serve as a reliable second assessor in scoring glomerular injury, offering potential benefits in enhancing the accuracy and objectivity of such assessments.
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Patients with inflammatory bowel disease (IBD) who experience long-term chronic inflammation of the colon are at an increased risk of developing colorectal cancer (CRC). Mitotic spindle positioning (MISP), an actin-binding protein, plays a role in mitosis and spindle positioning. MISP is found on the apical membrane of the intestinal mucosa and helps stabilize and elongate microvilli, offering protection against colitis. This study explored the role of MISP in colorectal tumorigenesis using a database, human CRC cells, and a mouse model for colitis-induced colorectal tumors triggered by azoxymethane (AOM)/dextran sodium sulfate (DSS) treatment. We found that MISP was highly expressed in colon cancer patient tissues and that reduced MISP expression inhibited cell proliferation. Notably, MISP-deficient mice showed reduced colon tumor formation in the AOM/DSS-induced colitis model. Furthermore, MISP was found to form a complex with Opa interacting protein 5 (OIP5) in the cytoplasm, influencing the expression of OIP5 in a unidirectional manner. We also observed that MISP increased the levels of phosphorylated STAT3 in the JAK2-STAT3 signaling pathway, which is linked to tumorigenesis. These findings indicate that MISP could be a risk factor for CRC, and targeting MISP might provide insights into the mechanisms of colitis-induced colorectal tumorigenesis.
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Colitis , Neoplasias Colorrectales , Animales , Humanos , Ratones , Azoximetano/efectos adversos , Carcinogénesis , Transformación Celular Neoplásica , Colitis/patología , Neoplasias Colorrectales/patología , Sulfato de Dextran/efectos adversos , Modelos Animales de Enfermedad , Janus Quinasa 2/metabolismo , Ratones Endogámicos C57BL , Transducción de Señal , Huso Acromático/metabolismo , Factor de Transcripción STAT3/metabolismoRESUMEN
Adriamycin (ADR) nephropathy is the most widely used nephropathy model to study the pathophysiological mechanisms of chronic kidney disease (CKD) in mice. However, its application is limited to a few mouse strains such as the BALB/c strain; the standard strain, C57BL/6J (B6J), does not develop ADR nephropathy. Nevertheless, Arif et al. reported that C57BL/6N (B6N), another standard strain, is ADR-susceptible. Since then, no follow-up reports or other studies have been published on ADR nephropathy in B6N mice. Therefore, the goal of this study was to determine whether B6N mice are indeed susceptible to ADR nephropathy and whether there are differences in ADR susceptibility among the substrains of C57BL/6NCrl (NCrl) and C57BL/6NJcl (NJcl). NCrl mice showed marked albuminuria and mesangial cell proliferation, which are associated with mild ADR nephropathy, confirming that NCrl mice were susceptible to ADR nephropathy. On the other hand, NJcl mice did not exhibit these symptoms. ADR nephropathy models are usually generated by administering ADR through the tail vein, but Arif et al. administered ADR through the orbital vein. Therefore, we investigated the effect of the route of administration on ADR nephropathy. The degree of ADR nephropathy was found to vary based on the route of administration: more severe nephropathy was observed upon administration through the tail vein than through the orbital vein. Therefore, we conclude that NCrl mice are susceptible to ADR nephropathy, and the severity of ADR-induced nephropathy through orbital vein administration is relatively lower than that through the tail vein.
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Doxorrubicina , Enfermedades Renales , Ratones , Animales , Doxorrubicina/efectos adversos , Ratones Endogámicos C57BL , Enfermedades Renales/inducido químicamente , Albuminuria/inducido químicamenteRESUMEN
Adriamycin (ADR) is an effective chemotherapy drug for various cancers but has serious side effects. ADR-induced liver damage is a common problem during therapy, but the underlying mechanism remains to be fully understood. In contrast, ADR-induced glomerular damage is well studied in rodents, and sensitivity to ADR-induced nephropathy is because of the R2140C polymorphism of Prkdc gene. To investigate whether strain differences or sensitivity to ADR-induced liver damage are related to Prkdc polymorphism, this study compared the sensitivity to ADR-induced liver damage among C57BL/6J (B6J), B6-PrkdcR2140C, and BALB/c mice. Although B6J exhibits resistance to ADR-induced liver injury, BALB/c and B6-PrkdcR2140C are more susceptible to liver injury, which is exacerbated by the presence of R2140C mutation in PRKDC.
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Enfermedad Hepática Inducida por Sustancias y Drogas , Enfermedades Renales , Animales , Ratones , Enfermedad Hepática Inducida por Sustancias y Drogas/genética , Enfermedad Hepática Inducida por Sustancias y Drogas/veterinaria , Doxorrubicina/toxicidad , Enfermedades Renales/inducido químicamente , Enfermedades Renales/veterinaria , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Polimorfismo GenéticoRESUMEN
Circadian rhythms are endogenous oscillators that regulate 24 h behavioral and physiological processes. Our previous investigation demonstrated that bromobenzene metabolite (4-bromocatechol: 4-BrCA) exhibited chronotoxicity (i.e., the nephrotoxicity induced by 4-BrCA was observed during the dark phase, while not observed at light phase in mice). However, the molecular mechanism is still unknown. The aim of the present study is to investigate the cellular molecule(s) involved in the 4-BrCA-induced nephrotoxicity using mouse renal cortex tubular cell lines (MuRTE61 cells). We found that 4-BrCA showed dose dependent (0.01-1 mM) cell proliferation defect in MuRTE61 cells. By treating with 0.03 mM 4-BrCA, we demonstrated that major clock genes (Bmal1, Clock, Cry1, Cry2, Per1, and Per2) were significantly downregulated. Interestingly, the expression levels of two genes, Bmal1 and Clock, continued to decrease after 3 h of treatment with 4-BrCA, while Cry1, Per1, and Per2 were unchanged until 24 h of treatment. Moreover, BMAL1 and CLOCK levels are higher at light phase. We speculated that BMAL1 and CLOCK might function defensively against 4-BrCA-induced nephrotoxicity since the expression levels of Bmal1 and Clock were rapidly decreased. Finally, overexpression of Bmal1 and Clock restored 4-BrCA-induced cell proliferation defect in MuRTE61 cells. Taken together, our results suggest that Bmal1 and Clock have protective roles against 4-BrCA-induced nephrotoxicity.
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Factores de Transcripción ARNTL , Bromobencenos , Ratones , Animales , Factores de Transcripción ARNTL/genética , Factores de Transcripción ARNTL/metabolismo , Ritmo Circadiano/genética , Regulación de la Expresión GénicaRESUMEN
Most mitochondrial diseases are hereditary and highly heterogeneous. Cattle born with the V79L mutation in the isoleucyl-tRNA synthetase 1 (IARS1) protein exhibit weak calf syndrome. Recent human genomic studies about pediatric mitochondrial diseases also identified mutations in the IARS1 gene. Although severe prenatal-onset growth retardation and infantile hepatopathy have been reported in such patients, the relationship between IARS mutations and the symptoms is unknown. In this study, we generated hypomorphic IARS1V79L mutant mice to develop an animal model of IARS mutation-related disorders. We found that compared to wild-type mice, IARSV79L mutant mice showed a significant increase in hepatic triglyceride and serum ornithine carbamoyltransferase levels, indicating that IARS1V79L mice suffer from mitochondrial hepatopathy. In addition, siRNA knockdown of the IARS1 gene decreased mitochondrial membrane potential and increased reactive oxygen species in the hepatocarcinoma-derived cell line HepG2. Furthermore, proteomic analysis revealed decreased levels of the mitochondrial function-associated protein NME4 (mitochondrial nucleoside diphosphate kinase). Concisely, our mutant mice model can be used to study IARS mutation-related disorders.
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Hepatopatías , Enfermedades Mitocondriales , Embarazo , Femenino , Humanos , Niño , Animales , Bovinos , Ratones , Proteómica , Isoleucina-ARNt Ligasa/genética , Genoma , Hepatopatías/genética , Enfermedades Mitocondriales/genética , MutaciónRESUMEN
Inflammatory bowel disease (IBD) is classified into two types: Crohn's disease and ulcerative colitis. In IBD, the imbalance between the pro-inflammatory and anti-inflammatory cytokines prevents recovery from the inflammatory state, resulting in chronic inflammation in the colon. The mitotic spindle positioning protein (MISP) is localized to the apical membrane in the colon. In this study, we observed increased expression of MISP in the intestinal epithelial cells in dextran sulfate sodium (DSS)-induced colitis in mice. MISP-deficient mice receiving DSS showed significant exacerbation of colitis (e.g., weight loss, loss of the crypts). The intestinal epithelial cells of the MISP-deficient mice showed a trend towards decreased cell proliferation after DSS treatment. Reverse transcription followed by quantitative polymerase chain reaction revealed that the expression levels of Tgfb1, an anti-inflammatory cytokine, were significantly reduced in the colon of MISP-deficient mice compared with the wild-type mice regardless of DSS treatment. These findings indicate that MISP may play a role in the recovery of the colon after inflammation through its anti-inflammatory and proliferative activities, suggesting that MISP may be a new therapeutic target for IBD.
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Colitis , Enfermedades Inflamatorias del Intestino , Animales , Ratones , Antiinflamatorios/uso terapéutico , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Colitis/metabolismo , Colitis/veterinaria , Colon/metabolismo , Citocinas/metabolismo , Sulfato de Dextran/toxicidad , Sulfato de Dextran/uso terapéutico , Modelos Animales de Enfermedad , Inflamación/tratamiento farmacológico , Inflamación/veterinaria , Enfermedades Inflamatorias del Intestino/inducido químicamente , Enfermedades Inflamatorias del Intestino/veterinaria , Ratones Endogámicos C57BL , Huso Acromático/metabolismoRESUMEN
Animal models of podocytopathy and chronic kidney diseases (CKD) help elucidate these pathologies. Adriamycin (ADR)-induced nephropathy is a common rodent model of podocytopathy. BALB/c mice are sensitive to ADR, whereas C57BL/6 (B6) mice, the most commonly used strain, are resistant to ADR. Therefore, mouse strains with the B6 genetic background cannot be used as an ADR nephropathy model. We previously generated DNA-dependent protein kinase catalytic subunit (Prkdc) mutant B6 mice (B6-PrkdcR2140C) carrying the R2140C mutation that causes ADR nephropathy. However, whether ADR nephropathy in the novel strain progresses to CKD after ADR administration has not been evaluated. Therefore, we examined whether the B6-PrkdcR2140C mice develop CKD after ADR administration. We also evaluated whether differences existed in the genetic background in ADR nephropathy by comparing the B6-PrkdcR2140C mice with BALB/c mice. Our findings demonstrated that B6-PrkdcR2140C progresses to CKD and is resistant to nephropathy compared with the BALB/c mice. The B6-PrkdcR2140C and BALB/c mice differed in the expression of genes related to inflammatory mediators, and further analysis is required to identify factors that contribute to resistance to nephropathy.
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Enfermedades Renales , Insuficiencia Renal Crónica , Ratones , Animales , Doxorrubicina/efectos adversos , Ratones Endogámicos C57BL , Enfermedades Renales/genética , Ratones Endogámicos BALB CRESUMEN
Cystinuria is an autosomal metabolic disorder caused by mutations in the SLC3A1 and SLC7A9 genes, encoding the amino acid transporter proteins rBAT and b0,+AT, respectively. Based on the causative gene, cystinuria is classified into 3 types: type A (SLC3A1), type B (SLC7A9), and type AB (SLC3A1 and SLC7A9). Patients with cystinuria exhibit hyperexcretion of cystine and dibasic amino acids in the urine and develop cystine crystals due to its low solubility in the urine, often resulting in calculus formation. In this study, we present an inbred strain FVB/NJcl mice affected with cystinuria. In the affected mouse kidney, Slc7a9 expression was completely abolished because of a large sequence deletion in the promoter region of the Slc7a9 mutant allele. Slc7a9-deficient mice with FVB/NJcl genetic background developed cystine calculi in the bladder with high penetrance, as compared to the previously reported mouse models of cystinuria. This model may be useful to understand the determinants of crystal aggregation, affecting calculus formation.
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Sistemas de Transporte de Aminoácidos Neutros , Aminoácidos Diaminos , Cálculos , Cistinuria , Ratones , Animales , Cistinuria/genética , Cistinuria/metabolismo , Sistemas de Transporte de Aminoácidos Básicos/genética , Cistina/metabolismo , Mutación , Modelos Animales de Enfermedad , Aminoácidos Diaminos/genética , Sistemas de Transporte de Aminoácidos Neutros/genéticaRESUMEN
Tensin 2 (TNS2), a focal adhesion protein, is considered to anchor focal adhesion proteins to ß integrin as an integrin adaptor protein and/or serve as a scaffold to facilitate the interactions of these proteins. In the kidney, TNS2 localizes to the basolateral surface of glomerular epithelial cells, i.e., podocytes. Loss of TNS2 leads to the development of glomerular basement membrane lesions and abnormal accumulation of extracellular matrix in maturing glomeruli during the early postnatal stages. It subsequently results in podocyte foot process effacement, eventually leading to glomerulosclerosis. Histopathological features of the affected glomeruli in the middle stage of the disease include expansion of the mesangial matrix without mesangial cell proliferation. In this review, we provide an overview of TNS2-deficient nephropathy and discuss the potential mechanism underlying this mechanosensitive nephropathy, which may be applicable to other glomerulonephropathies, such as CD151-deficient nephropathy and Alport syndrome. The onset of TNS2-deficient nephropathy strictly depends on the genetic background, indicating the presence of critical modifier genes. A better understanding of molecular mechanisms of mechanosensitive nephropathy may open new avenues for the management of patients with glomerulonephropathies.
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Enfermedades Renales , Podocitos , Animales , Predisposición Genética a la Enfermedad , Membrana Basal Glomerular/metabolismo , Membrana Basal Glomerular/patología , Humanos , Riñón , Enfermedades Renales/genética , Podocitos/metabolismoRESUMEN
Adriamycin (ADR)-induced nephropathy is frequently utilized in rodent models of podocytopathy. However, the application of this model in mice is limited to a few strains, such as BALB/c mice. The most commonly used mouse strain, C57BL/6 (B6), is resistant to ADR-induced nephropathy, as are all mouse strains with a B6 genetic background. Reportedly, the R2140C variant of the Prkdc gene is the cause of susceptibility to ADR-induced nephropathy in mice. To verify this hypothesis, we produced Prkdc mutant B6 mice, termed B6-PrkdcR2140C, that possess the R2140C mutation. After administration of ADR, B6-PrkdcR2140C mice exhibited massive proteinuria and glomerular and renal tubular injuries. In addition, there was no significant difference in the severity between B6-PrkdcR2140C and BALB/c. These findings demonstrated that B6-PrkdcR2140C show ADR-induced nephropathy susceptibility at a similar level to BALB/c, and that the PRKDC R2140C variant causes susceptibility to ADR-induced nephropathy. In future studies, ADR-induced nephropathy may become applicable to various kinds of genetically modified mice with a B6 background by mating with B6-PrkdcR2140C.
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Sustitución de Aminoácidos , Proteína Quinasa Activada por ADN/genética , Proteínas de Unión al ADN/genética , Modelos Animales de Enfermedad , Doxorrubicina/farmacología , Enfermedades Renales/inducido químicamente , Albuminuria/inducido químicamente , Albuminuria/complicaciones , Animales , Secuencia de Bases , Biomarcadores , Sistemas CRISPR-Cas , Proteína Quinasa Activada por ADN/metabolismo , Proteínas de Unión al ADN/metabolismo , Femenino , Enfermedades Renales/complicaciones , Enfermedades Renales/metabolismo , Enfermedades Renales/patología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Mutación , Insuficiencia Renal/inducido químicamente , Insuficiencia Renal/complicaciones , Insuficiencia Renal/metabolismo , Insuficiencia Renal/patologíaRESUMEN
Mast cell-deficient mice are helpful for understanding the roles of mast cells in vivo. To date, a dozen mouse models for mast cell deficiency have been reported. However, mice with a specific depletion of all populations of mast cells have not been reported. We generated knock-in mice, termed Mcpt5/Cma1DTR mice, expressing human diphtheria toxin A (DT) receptor under the endogenous promoter of Mcpt5 (also known as Cma1), which encodes mouse mast cell protease-5. Flow cytometry and histological analysis showed that intraperitoneal injection of DT induced almost complete depletion of mast cells in heterozygote Mcpt5/Cma1DTR/+ mice. The deletion rates of mast cells in peritoneal cavity, mesentery, abdominal skin, ear skin, and glandular stomach were 99.9%, 100%, 98.7%, 97.7%, and 100%, respectively. Passive cutaneous anaphylaxis reaction also revealed mast cell deficiency in ear skin after DT treatment. Other than mast cells, a small percentage of marginal zone B cells in Mcpt5/Cma1DTR/+ mice were killed by DT treatment. In conclusion, the Mcpt5/Cma1DTR/+ mouse model is valuable for achieving conditional depletion of all populations of mast cells without inducing a marked reduction in other cells.
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Separación Celular/métodos , Quimasas/genética , Mastocitos/citología , Modelos Animales , Animales , Células del Tejido Conectivo/citología , Femenino , Humanos , Inyecciones Intraperitoneales , Ratones , Membrana Mucosa/citología , Regiones Promotoras Genéticas/genéticaRESUMEN
The number of patients with chronic kidney disease (CKD) is growing continuously globally. In order to study pathogenesis and mechanisms, many animal models have been developed, including spontaneous, genetic, and induced models. Although each type of CKD shows disease-specific tissue changes in the early stages, tubular disorder and interstitial fibrosis histologically occur in the course of progression to end-stage renal failure. Therefore, the quantification of tubular disorder and interstitial fibrosis in CKD research using animal models is essential for measuring the degree of CKD severity and, thus, efficacy of therapeutic agents. Several strategies have been used to quantify interstitial fibrosis. Among scoring factors, renal tubular flattening can be quantitatively evaluated easily and inexpensively. However, the diagnostic value of renal tubular flattening evaluation has not been investigated previously. Therefore, in this study, we investigated the correlation between renal tubular flattening and interstitial fibrosis or renal tubular injury markers. We observed a strong correlation between the degree of tubular injury/interstitial fibrosis and renal tubular flattening in three types of mouse renal disease model. This is advantageous because rapidly advancing technologies such as artificial intelligence and image processing can be easily applied; hence, a more precise, objective, and quantitative diagnosis should be possible in the future.
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Insuficiencia Renal Crónica , Enfermedades de los Roedores , Animales , Inteligencia Artificial , Modelos Animales de Enfermedad , Fibrosis , Riñón/patología , Túbulos Renales/patología , Ratones , Insuficiencia Renal Crónica/veterinaria , Enfermedades de los Roedores/patologíaRESUMEN
Diabetic animal models have made significant contributions to understanding the etiology of diabetes and to the development of new medications. Our research group recently developed a novel diabetic mouse strain, the insulin hyposecretion (ihs)mouse. The strain involves neither obesity nor insulitis but exhibits notable pancreatic ß-cell dysfunction, distinguishing it from other well-characterized animal models. In ihs mice, severe impairment of insulin secretion from pancreas has been elicited by glucose or potassium chloride stimulation. To clarify the genetic basis of impaired insulin secretion, beginning with identifying the causative gene, genetic linkage analysis was performed using [(C57BL/6 × ihs) F1 × ihs] backcross progeny. Genetic linkage analysis and quantitative trait loci analysis for blood glucose after oral glucose loading indicated that a recessively acting locus responsible for impaired glucose tolerance was mapped to a 14.9-Mb region of chromosome 18 between D18Mit233 and D18Mit235 (the ihs locus). To confirm the gene responsible for the ihs locus, a congenic strain harboring the ihs locus on the C57BL/6 genetic background was developed. Phenotypic analysis of B6.ihs-(D18Mit233-D18Mit235) mice showed significant glucose tolerance impairment and markedly lower plasma insulin levels during an oral glucose tolerance test. Whole-genome sequencing and Sanger sequencing analyses on the ihs genome detected two ihs-specific variants changing amino acids within the ihs locus; both variants in Slc25a46 and Tcerg1 were predicted to disrupt the protein function. Based on information regarding gene functions involving diabetes mellitus and insulin secretion, reverse-transcription quantitative polymerase chain reaction analysis revealed that the relative abundance of Reep2 and Sil1 transcripts from ihs islets was significantly decreased whereas that of Syt4 transcripts were significantly increased compared with those of control C57BL/6 mice. Thus, Slc25a46, Tcerg1, Syt4, Reep2 and Sil1 are potential candidate genes for the ihs locus. This will be the focus of future studies in both mice and humans.
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Diabetes Mellitus Tipo 2/genética , Sitios Genéticos , Animales , Glucemia/análisis , Diabetes Mellitus Tipo 2/patología , Modelos Animales de Enfermedad , Ligamiento Genético , Prueba de Tolerancia a la Glucosa , Secreción de Insulina , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Fenotipo , Proteínas de Transporte de Fosfato/genética , Proteínas de Transporte de Fosfato/metabolismo , Sinaptotagminas/genética , Sinaptotagminas/metabolismo , Factores de Elongación Transcripcional/genética , Factores de Elongación Transcripcional/metabolismoRESUMEN
Tensin2 (TNS2) is a focal adhesion-localized protein possessing N-terminal tandem protein tyrosine phosphatase (PTPase) and C2 domains, and C-terminal tandem Src homology 2 (SH2) and phosphotyrosine binding (PTB) domains. Genetic deletion of Tns2 in a susceptible murine strain leads to podocyte alterations after birth. To clarify the domain contributions to podocyte maintenance, we generated two Tns2-mutant mice with the genetic background of the susceptible FVB/NJ strain, Tns2∆C and Tns2CS mice, carrying a SH2-PTB domain deletion and a PTPase domain inactivation, respectively. The Tns2∆C mice developed massive albuminuria, severe glomerular injury and podocyte alterations similarly to those in Tns2-deficient mice. In contrast, the Tns2CS mice showed no obvious phenotypic abnormalities. These results indicate that the TNS2 SH2-PTB domain, but not its PTPase activity, plays a role in podocyte maintenance. Furthermore, in a podocyte cell line, the truncated TNS2 mutant lacking the SH2-PTB domain lost the ability to localize to focal adhesion. Taken together, these data suggest that TNS2 recruitment to focal adhesion is required to maintain postnatal podocytes on a susceptible genetic background.
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Eliminación de Gen , Podocitos/patología , Proteínas Tirosina Fosfatasas/metabolismo , Tensinas/genética , Animales , Ratones , Ratones TransgénicosRESUMEN
The human cell line HK-2 is most commonly used as a model of renal proximal tubular epithelial cells (PTECs) for various studies despite the absence or low expression of transporters characteristic of parental PTECs. In an effort to develop reliable PTEC models, several human cell lines have been newly established over the last decade. In contrast, reliable mouse PTEC models are still unavailable. In this study, we established immortalized renal cortex tubule cell lines derived from p53 knockout mice and evaluated various PTEC characteristics toward the development of reliable mouse PTEC models. Here, we focus on MuRTE61, one of 13 newly established clonal cell lines. Albumin uptake in MuRTE61 cells was verified by incubation with fluorescent dye-labeled albumin. RT-PCR confirmed the expression of efflux transporter genes characteristic of PTECs in the MuRTE61 cells. MuRTE61 cells exhibited high sensitivity to treatment with cisplatin, a nephrotoxic agent, accompanied by upregulated expression of the uptake transporter Slc22a2 gene. Furthermore, MuRTE61 cells consistently formed spheroids with a lumen and apicobasal polarity in three-dimensional Matrigel cultures. Apical brush border microvilli were also observed in the spheroids by transmission electron microscopy. These data validate that MuRTE61 can be characterized as a reliable mouse PTEC line. In future, detailed analysis of reliable mouse and human PTEC lines will provide an accurate extrapolation of results of experiments using mice and humans, and may help resolve apparent inconsistencies between mouse and human nephrotoxicity.
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AIMS/INTRODUCTION: Diabetic animal models have made an enormous contribution to our understanding of the etiology of diabetes and the development of new medications. The aim of the present study was to develop and characterize a novel, non-obese murine strain with spontaneous diabetes - the insulin hyposecretion (ihs) mouse. MATERIALS AND METHODS: During the development of the ICGN.B6-Tns2WT strain as the control for the ICGN-Tns2nph congenital nephrotic strain, diabetic mice were discovered and named ihs mice. Intraperitoneal insulin tolerance test, oral glucose tolerance test and an insulin secretion experiment by the pancreas perfusion system were carried out on ihs mice. The pancreatic islets were examined histologically, and the mRNA expression of pancreatic ß-cell-specific genes or genes associated with monogenic diabetes was examined by RT-qPCR. RESULTS: The ihs mice showed several distinctive diabetes-related characteristics: (i) the onset of diabetes was observed only in the male mice; (ii) there were no differences in insulin content between the ihs and control mice; (iii) impaired insulin secretion was elicited by glucose, potassium chloride and sulfonylureas; (iv) there was a significant reduction of relative ß-cell volume with no signs of inflammation or fibrosis; (v) they showed a normal glycemic response to exogenous insulin; and (vi) the mice were not obese. CONCLUSIONS: The ihs mouse provides a novel murine model of congenital diabetes that shows insulin secretion failure. This model allows not only an analysis of the progression of diabetes, but also the identification of unknown genes involved in insulin secretion.
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Diabetes Mellitus Experimental/etiología , Diabetes Mellitus Experimental/patología , Secreción de Insulina , Células Secretoras de Insulina/patología , Tensinas/fisiología , Animales , Glucemia/análisis , Diabetes Mellitus Experimental/metabolismo , Femenino , Células Secretoras de Insulina/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos ICRRESUMEN
BACKGROUND: Tensin2 is a focal adhesion-localized multidomain protein expressed in various tissues, and its dysfunction leads to alterations in podocytes. However, these podocyte-related manifestations are dependent on murine strain. Tensin2 dysfunction results in susceptible strains developing podocyte foot process effacement and massive albuminuria, whereas podocytes in resistant strains remain almost intact. In our previous studies, quantitative trait loci analysis and congenic analysis using resistant C57BL/6J and susceptible ICGN mice identified a modifier locus associated with podocyte injury caused by tensin2 dysfunction on chromosome 2. However, the effect of this modifier locus on chromosome 2 is insufficient to explain the resistance of C57BL/6J mice to tensin2 dysfunction, indicating the existence of other modifier genes. RESULTS: Whereas previous studies focused on the severity of chronic kidney disease, the present study focused on podocyte injury. We performed a genome-wide linkage analysis of backcrosses between two tensin2-deficient mouse strains, B6.ICGN-Tns2 nph and FVB.ICGN-Tns2 nph , and detected a novel major modifier locus on chromosome 10. The combined effect of the C57BL/6J alleles of the two loci on chromosomes 2 and 10 reduced the urinary albumin excretion caused by tensin2 dysfunction to a level comparable to that of C57BL/6J mice. CONCLUSIONS: These data indicate that the resistance to podocyte injury caused by tensin2 dysfunction is mainly produced by the effects of the modifier genes on the two loci. The identification of these modifier genes is expected to help elucidate the mechanism underlying podocyte injury.
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Albuminuria/genética , Podocitos/metabolismo , Insuficiencia Renal Crónica/genética , Tensinas/genética , Animales , Ligamiento Genético , Ratones , Ratones Endogámicos C57BL , Sitios de Carácter CuantitativoRESUMEN
IL-36α, a member of the IL-1 family, is a crucial mediator of inflammatory responses. We previously found that IL-36α was overexpressed in injured distal tubules (DTs); however, its pathological function remains unclear. Herein, unilateral ureter obstruction (UUO) or folic acid (FA) injection was performed in mouse kidneys to assess the role of IL-36α in kidney injury. IL-36α mRNA and protein expression significantly increased in the kidneys within 24 h after UUO. IL-36α localized to dilated DTs. IL-36α expression significantly correlated with the progression of tubulointerstitial cell infiltration and tubular epithelium cell death in UUO kidneys and with renal dysfunction in FA-induced acute kidney injury mice. At 24 h after UUO, IL-36α+ DT epithelial cells showed loose intercellular digitations. IL-1RL2, an IL-36α receptor protein, localized to podocytes, proximal tubules, and DTs in the healthy kidney. IL-1RL2 was expressed in interstitial cells and platelets or extended primary cilia of DT epithelial cells in UUO kidneys. IL-36α stimulation promoted the production of IL-6 and Prss35, an inflammatory cytokine and collagen remodeling-associated enzyme, respectively, in cultured NIH3T3 fibroblasts. UUO-treated IL-36α-knockout (KO) mice showed milder kidney injury features than wild-type (WT) mice did. In UUO kidneys from IL-36α-KO mice, the expression of genes associated with inflammatory response and sensory perception was significantly different from that in WT mice. Altogether, our data indicate an association between intrarenal IL-36α overexpression and the progression of tubulointerstitial inflammations and morpho-functional alterations of DT epithelial cells. IL-36α may be a novel kidney injury marker useful for evaluating DT damages.
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Background and study aim Endoscopic submucosal dissection (ESD) is known as a curative treatment for colorectal superficial neoplasms. There is however a need for more long-term clinical data to establish the full advantages of colorectal ESD regarding very low recurrence rates. The aim of this retrospective study was to determine long-term clinical outcomes of colorectal ESD. Methods A total of 423 lesions treated by ESD for colorectal adenoma/dysplasia or adenocarcinoma between 1998 and 2008âat a single high volume referral center were included. We conducted a retrospective survey on patients with follow-up and obtained complete 1-, 3-, and 5-year outcome data for 358 (85â%), 292 (69â%), and 209 (49â%) lesions, respectively. Curative resection was defined when the pathological specimen had carcinoma-free resection margins, irrespective of piecemeal or en bloc resection, without submucosal deep invasion (≥â1000âµm), lymphovascular involvement, or a poorly differentiated adenocarcinoma component. Results After a median 4.9 years of follow-up, the 3-year overall cumulative endoscopic recurrence rate and cancerous recurrence rate were 2.9â% (95â% confidence interval [95â%CI] 1.2â-â4.7) and 1.1â% (0â-â2.1), respectively. The 5-year overall cumulative endoscopic recurrence and cancerous recurrence rates were 3.8â% (1.7â-â5.9) and 1.6â% (0.1â-â3.0), respectively. In 361 lesions eligible for endoscopic follow-up, the 3-year endoscopic recurrence and cancerous recurrence rates were 2.4â% (0.8â-â4.1) and 0.4â% (0â-â1.4), respectively. Multivariate analysis revealed that piecemeal resection and submucosal deep tumor invasion were associated with recurrence. Conclusions The current study demonstrated favorable long-term clinical outcomes of colorectal ESD when en bloc curative resection is achieved.