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1.
Glomerular Dis ; 3(1): 148-154, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37901695

RESUMO

Background: The association between viral infections and glomerular diseases, commonly known as "viral glomerulopathies," has been described in various clinical scenarios for decades. Despite advancements in diagnostic tools, it remains challenging to establish a causative link fully. Summary: Data from mouse models have substantiated clinical observations and implicate direct viral infection in the pathogenesis of viral glomerulopathy, particularly in human immunodeficiency virus-associated nephropathy. In addition to the traditional concept of direct viral effects on kidneys, other factors such as APOL1 risk alleles can further modify the clinical outcomes or presentations of different viral glomerulopathies. Newly developed antiviral drugs are now applicable to a wider range of patients with lower kidney function and fewer side effects. Key Message: Efforts focusing on vaccines and antiviral treatments have significantly reduced the incidence of viral glomerulopathies. However, the most recent pandemic caused by severe acute respiratory syndrome coronavirus 2 infection complicated by COVID-associated nephropathy illustrates our susceptibility to novel viruses. Ongoing research is pivotal to deciphering the mechanisms behind viral glomerulopathies and discovering therapeutics in a collaborative approach.

2.
J Immunol ; 210(1): 19-23, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36454023

RESUMO

T cell-independent (TI) B cell responses to nonprotein Ags involve multiple cues from the innate immune system. Neutrophils express complement receptors and activated neutrophils can release BAFF, but mechanisms effectively linking neutrophil activation to TI B cell responses are incompletely understood. Using germline and conditional knockout mice, we found that TI humoral responses involve alternative pathway complement activation and neutrophil-expressed C3a and C5a receptors (C3aR1/C5aR1) that promote BAFF-dependent B1 cell expansion and TI Ab production. Conditional absence of C3aR1/C5aR1 on neutrophils lowered serum BAFF levels, led to fewer Peyer's patch germinal center B cells, reduced germinal center B cells IgA class-switching, and lowered fecal IgA levels. Together, the results indicate that sequential activation of complement on neutrophils crucially supports humoral TI and mucosal IgA responses through upregulating neutrophil production of BAFF.


Assuntos
Linfócitos B , Neutrófilos , Camundongos , Animais , Proteínas do Sistema Complemento/metabolismo , Camundongos Knockout , Receptores de Complemento/metabolismo , Imunoglobulina A
3.
Int J Mol Sci ; 23(24)2022 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-36555356

RESUMO

Apart from the paternal half of the genetic material, the male gamete carries assorted epigenetic marks for optimal fertilization and the developmental trajectory for the early embryo. Recent works showed dynamic changes in small noncoding RNA (sncRNA) in spermatozoa as they transit through the testicular environment to the epididymal segments. Studies demonstrated the changes to be mediated by epididymosomes during the transit through the adluminal duct in the epididymis, and the changes in sperm sncRNA content stemmed from environmental insults significantly altering the early embryo development and predisposing the offspring to metabolic disorders. Here, we review the current knowledge on the establishment of the sperm sncRNA transcriptome and their role in male-factor infertility, evidence of altered offspring health in response to the paternal life experiences through sperm sncRNA species and, finally, their implications in assisted reproductive technology in terms of epigenetic inheritance.


Assuntos
Pequeno RNA não Traduzido , Transcriptoma , Masculino , Humanos , Sêmen , Espermatozoides/metabolismo , Reprodução , Epididimo/metabolismo , Pequeno RNA não Traduzido/genética , Pequeno RNA não Traduzido/metabolismo
4.
Kidney Int ; 102(6): 1291-1304, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36108806

RESUMO

The pathogenesis of diabetic kidney disease (DKD) involves multifactorial processes that converge to initiate and advance the disease. Although DKD is not typically classified as an inflammatory glomerular disease, mounting evidence supports the involvement of kidney inflammation as a key contributor in DKD pathogenesis, particularly through macrophages. However, detailed identification and corresponding phenotypic changes of macrophages in DKD remain poorly understood. To capture the gene expression changes in specific macrophage cell subsets in early DKD, we performed single-cell transcriptomic analysis of CD45-enriched kidney immune cells from type 1 diabetic OVE26 mice at two time points during the disease development. We also undertook a focused analysis of mononuclear phagocytes (macrophages and dendritic cells). Our results show increased resident and infiltrating macrophage subsets in the kidneys of mice with diabetes over time, with heightened expression of pro-inflammatory or anti-inflammatory genes in a subset-specific manner. Further analysis of macrophage polarization states in each subset in the kidneys showed changes consistent with the continuum of activation and differentiation states, with gene expression tending to shift toward undifferentiated phenotypes but with increased M1-like inflammatory phenotypes over time. By deconvolution analysis of RNAseq samples and by immunostaining of biopsies from patients with DKD, we further confirmed a differential expression of select genes in specific macrophage subsets essentially recapitulating the studies in mice. Thus, our study provides a comprehensive analysis of macrophage transcriptomic profiles in early DKD that underscores the dynamic macrophage phenotypes in disease progression.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Camundongos , Animais , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/metabolismo , Rim/patologia , Glomérulos Renais/patologia , Ativação de Macrófagos , Macrófagos/metabolismo , Diabetes Mellitus/metabolismo
5.
J Clin Invest ; 132(16)2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35968780

RESUMO

Understanding the loss of kidney function resulting from kidney aging has become an emerging research focus that will facilitate the future development of antisenolytic treatments. In this issue of the JCI, Pippin et al. first identified PD-1 upregulation in the aged mouse podocyte via unbiased RNA-seq analysis. Overexpression of PD-1 in immortalized mouse podocytes induced cell death and a senescence-associated secretory phenotype, suggesting the pathological role of PD-1 upregulation in aged podocytes. Blocking PD-1 signaling via a neutralizing anti-PD-1 antibody reversed the aged phenotype in the aged mice and ameliorated proteinuria in an experimental focal segmental glomerulosclerosis (FSGS) mouse model. These findings highlight the role of PD-1 signaling in kidney aging and its therapeutic potential for human clinical trials.


Assuntos
Glomerulosclerose Segmentar e Focal , Podócitos , Idoso , Animais , Glomerulosclerose Segmentar e Focal/genética , Glomerulosclerose Segmentar e Focal/patologia , Humanos , Rim/metabolismo , Glomérulos Renais/patologia , Camundongos , Podócitos/patologia , Proteinúria/patologia
6.
BMC Biol ; 20(1): 78, 2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-35351114

RESUMO

BACKGROUND: Spermatogenesis is regulated by a complex network of intercellular communication processes. Extracellular vesicles (EVs) are one of the important mediators in intercellular communication. Previous reports have demonstrated the involvement of EVs from the epididymis and prostate in sperm maturation and function. However, the presence of EVs in the testis and their potential involvement in spermatogenesis has not been explored. Here, we have established a testis dissociation protocol that allows the isolation and characterization of testicular EVs. RESULTS: We show that testicular EVs are specifically and efficiently taken up by somatic cells and germ cells, including the spermatozoa in the interstitial space and the seminiferous tubule compartments. We profiled the proteome of testicular EVs and probed the cell types that release them, revealing the potential contributions from the Leydig cells and testicular macrophages. Moreover, we sequenced the small RNA cargoes of testicular EVs and identified sets of small non-coding RNAs that were overlooked in the testis transcriptome. Selected miRNA candidates in testicular EVs were found in sperm RNA payload and demonstrated specific resistance towards ribonuclease A independent of the vesicle membrane. Small molecule inhibition of EV secretion perturbed spermatogenesis via inter-compartmental communication. CONCLUSIONS: Together, our study provides a valuable resource on the repertoire of cargoes carried by testicular EVs and uncovers a physiological function of testicular EVs in inter-compartmental communication associated to spermatogenesis.


Assuntos
Vesículas Extracelulares , MicroRNAs , Comunicação Celular , Vesículas Extracelulares/metabolismo , Humanos , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Espermatogênese , Testículo/metabolismo
7.
Cell Metab ; 33(10): 1901-1903, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34614404

RESUMO

In a new study, Zhu et al. (2021) show that mitigating dysbiosis by the probiotic L. casei Zhang reduces kidney inflammation via restoring short-chain fatty acid-producing gut microbiome and nicotinamide metabolism. These findings shed light on the underlying mechanisms of probiotics in treating human kidney diseases.


Assuntos
Microbioma Gastrointestinal , Probióticos , Insuficiência Renal Crônica , Disbiose , Humanos , Rim , Insuficiência Renal Crônica/terapia
9.
Kidney Med ; 3(5): 860-863, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34278290

RESUMO

Here we present the first case of newly diagnosed IgA nephropathy (IgAN) after a SARS-CoV-2 vaccination. A 30-year-old man with no known past medical history presented with gross hematuria and subnephrotic proteinuria 24 hours after the second dose of the mRNA-1273 SARS-CoV-2 vaccine. A kidney biopsy showed IgAN. He was started on an angiotensin receptor blocker, resulting in proteinuria reduction. Similar to natural infection of SARS-CoV-2, persons who receive 2 mRNA-based vaccines demonstrate robust antibodies against the receptor-binding domain (RBD) of the S1 protein. Given the uniqueness of glycosylation of RBD and potent stimulation of immune response from mRNA-based vaccine compared to other vaccines, we hypothesize that our patient developed de novo antibodies, leading to IgA-containing immune-complex deposits. This case highlights the urgency of understanding the immunological responses to novel mRNA-based SARS-CoV-2 vaccines in more diverse populations. Despite the lack of clear causality, nephrologists should be alerted if any new-onset hematuria or proteinuria is observed.

12.
Toxicol Rep ; 7: 1564-1570, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33294387

RESUMO

Cadmium (Cd2+) is considered a human carcinogen as it causes oxidative stress and alters DNA repair responses. However, how Cd2+ is taken up by cells remains unclear. We hypothesized that Cd2+ could be transported into cells via a membrane copper (Cu) transporter, CTR1. CTR1 expression was not affected by Cd2+ exposure at the mRNA or protein level. Stable cell lines overexpressing either hCTR1, in the human liver cell line HepG2, or zCTR1, in the zebrafish liver cell line ZFL, were created to study their responses to Cd2+ insult. It was found that both HepG2 and ZFL cells overexpressing CTR1 had higher Cd2+ uptake and thus became sensitive to Cd2+. In contrast, hCTR1 knockdown in HepG2 cells led to a reduced uptake of Cd2+, making the cells relatively resistant to Cd2+. Localization studies revealed that hCTR1 had a clustered pattern after Cd2+ exposure, possibly in an attempt to reduce both Cd2+ uptake and Cd2+-induced toxicity. These in vitro results indicate that CTR1 can transport Cd2+ into the cell, resulting in Cd2+ toxicity.

13.
Front Immunol ; 11: 583702, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33117396

RESUMO

Individuals with kidney failure are at increased risk of cardiovascular events, as well as infections and malignancies, but the associated immunological abnormalities are unclear. We hypothesized that the uremic milieu triggers a chronic inflammatory state that, while accelerating atherosclerosis, promotes T cell exhaustion, impairing effective clearance of pathogens and tumor cells. Clinical and demographic data were collected from 78 patients with chronic kidney disease (CKD) (n = 42) or end-stage kidney disease (ESKD) (n = 36) and from 18 healthy controls (HC). Serum cytokines were analyzed by Luminex. Immunophenotype of T cells was performed by flow cytometry on peripheral blood mononuclear cells. ESKD patients had significantly higher serum levels of IFN-γ, TNF-α, sCD40L, GM-CSF, IL-4, IL-8, MCP-1, and MIP-1ß than CKD and HC. After mitogen stimulation, both CD4+ and CD8+ T cells in ESKD group demonstrated a pro-inflammatory phenotype with increased IFN-γ and TNF-α, whereas both CKD and ESKD patients had higher IL-2 levels. CKD and ESKD were associated with increased frequency of exhausted CD4+ T cells (CD4+KLRG1+PD1+CD57-) and CD8+ T cells (CD8+KLRG1+PD1+CD57-), as well as anergic CD4+ T cells (CD4+KLRG1-PD1+CD57-) and CD8+ T cells (CD8+KLRG1-PD1+CD57-). Although total percentage of follicular helper T cell (TFH) was similar amongst groups, ESKD had reduced frequency of TFH1 (CCR6-CXCR3+CXCR5+PD1+CD4+CD8-), but increased TFH2 (CCR6-CXCR3-CXCR5+PD1+CD4+CD8-), and plasmablasts (CD3-CD56-CD19+CD27highCD38highCD138-). In conclusion, kidney failure is associated with pro-inflammatory markers, exhausted T cell phenotype, and upregulated TFH2, especially in ESKD. These immunological changes may account, at least in part, for the increased cardiovascular risk in these patients and their susceptibility to infections and malignancies.


Assuntos
Insuficiência Renal/imunologia , Células T Auxiliares Foliculares/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Células Cultivadas , Citocinas/imunologia , Feminino , Humanos , Leucócitos Mononucleares/imunologia , Masculino , Pessoa de Meia-Idade
14.
Toxicol In Vitro ; 66: 104856, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32278528

RESUMO

Copper (Cu) is an essential element regulated by four genes (hCTR1, hATOX1, hATP7A, and hATP7B in humans and zctr1, zatox1, zatp7a, and zatp7b in zebrafish) in copper uptake, distribution, and transport in animal cells. Zebrafish (Danio rerio) shows a higher endogenous ratio of zatp7a to zatp7b in the liver, is relatively intolerant to copper ions and has a different zatp7a and zatp7b expression patterns in different organs. As high-affinity copper transporters, both zctr1 and hCTR1 increased copper toxicity, whereas hATOX1 and zatox1 slightly reduced copper toxicity in HepG2 cells after copper administration for 24 h. The transfected zatp7b functioned in HepG2 cells as effectively as hATP7B after both 24-h and 96-h copper exposure, but zatp7a failed to function in HepG2 cells as effectively as hATP7A. Our findings suggest that ATP7A dysfunction would increase cytotoxicity in the liver; the reason for zebrafish's copper intolerance could be the bulk dysfunction and abnormal localization of zATP7A.


Assuntos
Proteínas de Transporte de Cobre/genética , Cobre/toxicidade , Fígado/metabolismo , Proteínas de Peixe-Zebra/genética , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2 , Humanos , Fígado/citologia , Peixe-Zebra
15.
Curr Opin Nephrol Hypertens ; 29(3): 310-318, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32205583

RESUMO

PURPOSE OF REVIEW: Despite improvements in acute kidney injury (AKI) detection, therapeutic options to halt the progression of AKI to chronic kidney disease (CKD) remain limited. In this review, we focus on recent discoveries related to the pathophysiology of the AKI to CKD continuum, particularly involving the renal tubular epithelial cells, and also discuss related ongoing clinical trials. While our focus is on injured renal tubular epithelial cells as initiators of the cascade of events resulting in paracrine effects on other cells of the kidney, the summation of maladaptive responses from various kidney cell types ultimately leads to fibrosis and dysfunction characteristic of CKD. RECENT FINDINGS: Recent findings that we will focus on include, but are not limited to, characterizations of: the association between cell cycle arrest and cellular senescence in renal tubular epithelial cells and its contribution to renal fibrosis, chronic inflammation with persistent cytokine production and lymphocyte infiltration among unrepaired renal tubules, mitochondrial dysfunction and a unique role of cytosolic mitochondria DNA in fibrogenesis, prolyl hydroxylase domain proteins as potential therapeutic targets, and novel mechanisms involving the Hippo/yes-associated protein/transcriptional coactivator with PDZ-binding pathway. SUMMARY: Potential therapeutic options to address CKD progression will be informed by a better understanding of fibrogenic pathways. Recent advances suggest additional drug targets in the various pathways leading to fibrosis.


Assuntos
Injúria Renal Aguda/complicações , Túbulos Renais/fisiopatologia , Rim/patologia , Insuficiência Renal Crônica/etiologia , Injúria Renal Aguda/fisiopatologia , Animais , Progressão da Doença , Fibrose , Humanos
16.
Front Med (Lausanne) ; 7: 599236, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33553201

RESUMO

Currently available treatments of diabetic kidney disease (DKD) remain limited despite improved understanding of DKD pathophysiology. The complement system is a central part of innate immunity, but its dysregulated activation is detrimental and results in systemic diseases with overt inflammation. Growing evidence suggests complement activation in DKD. With existent drugs and clinical success of treating other kidney diseases, complement inhibition has emerged as a potential novel therapy to halt the progression of DKD. This article will review DKD, the complement system's role in diabetic and non-diabetic disease, and the potential benefits of complement targeting therapies especially for DKD patients.

17.
Appl Biosaf ; 24(2): 64-71, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36033940

RESUMO

Introduction: The international synthetic biology competition iGEM (formally known as the international Genetically Engineered Machines competition) has a dedicated biosafety and biosecurity program. Method: A review of specific elements of the program and a series of concrete examples illustrate how experiences in implementing the program have helped improved policy, including an increasing diversity of sources for genetic parts and organisms, keeping pace with technical developments, considering pathways toward future environmental release, addressing antimicrobial resistance, and testing the efficacy of current biosecurity arrangements. Results: iGEM's program is forward-leaning, in that it addresses both traditional (pathogen-based) and emerging risks both in terms of new technologies and new risks. It is integrated into the technical work of the competition-with clearly described roles and responsibilities for all members of the community. It operates throughout the life cycle of projects-from project design to future application. It makes use of specific tools to gather and review biosafety and biosecurity information, making it easier for those planning and conducting science and engineering to recognize potential risks and match them with appropriate risk management approaches, as well as for specialists to review this information to identify gaps and strengthen plans. Discussion: Integrating an increasingly adaptive risk management approach has allowed iGEM's biosafety and biosecurity program to become comprehensive, be cross-cutting, and cover the competition's life cycle.

18.
J Biol Chem ; 294(7): 2500-2518, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30538132

RESUMO

Reversible ubiquitination of G protein-coupled receptors regulates their trafficking and signaling; whether deubiquitinases regulate myocardial ß1-adrenergic receptors (ß1ARs) is unknown. We report that ubiquitin-specific protease 20 (USP20) deubiquitinates and attenuates lysosomal trafficking of the ß1AR. ß1AR-induced phosphorylation of USP20 Ser-333 by protein kinase A-α (PKAα) was required for optimal USP20-mediated regulation of ß1AR lysosomal trafficking. Both phosphomimetic (S333D) and phosphorylation-impaired (S333A) USP20 possess intrinsic deubiquitinase activity equivalent to WT activity. However, unlike USP20 WT and S333D, the S333A mutant associated poorly with the ß1AR and failed to deubiquitinate the ß1AR. USP20-KO mice showed normal baseline systolic function but impaired ß1AR-induced contractility and relaxation. Dobutamine stimulation did not increase cAMP in USP20-KO left ventricles (LVs), whereas NKH477-induced adenylyl cyclase activity was equivalent to WT. The USP20 homolog USP33, which shares redundant roles with USP20, had no effect on ß1AR ubiquitination, but USP33 was up-regulated in USP20-KO hearts suggesting compensatory regulation. Myocardial ß1AR expression in USP20-KO was drastically reduced, whereas ß2AR expression was maintained as determined by radioligand binding in LV sarcolemmal membranes. Phospho-USP20 was significantly increased in LVs of wildtype (WT) mice after a 1-week catecholamine infusion and a 2-week chronic pressure overload induced by transverse aortic constriction (TAC). Phospho-USP20 was undetectable in ß1AR KO mice subjected to TAC, suggesting a role for USP20 phosphorylation in cardiac response to pressure overload. We conclude that USP20 regulates ß1AR signaling in vitro and in vivo Additionally, ß1AR-induced USP20 phosphorylation may serve as a feed-forward mechanism to stabilize ß1AR expression and signaling during pathological insults to the myocardium.


Assuntos
Endopeptidases/biossíntese , Regulação Enzimológica da Expressão Gênica , Ativação do Canal Iônico , Miocárdio/metabolismo , Receptores Adrenérgicos beta 1/metabolismo , Substituição de Aminoácidos , Animais , Endopeptidases/genética , Ventrículos do Coração , Camundongos , Camundongos Knockout , Mutação de Sentido Incorreto , Fosforilação , Receptores Adrenérgicos beta 1/genética , Ubiquitina Tiolesterase , Ubiquitinação
19.
Front Med (Lausanne) ; 5: 221, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30255020

RESUMO

Proteinuric kidney diseases are a group of disorders with diverse pathological mechanisms associated with significant losses of protein in the urine. The glomerular filtration barrier (GFB), comprised of the three important layers, the fenestrated glomerular endothelium, the glomerular basement membrane (GBM), and the podocyte, dictates that disruption of any one of these structures should lead to proteinuric disease. Podocytes, in particular, have long been considered as the final gatekeeper of the GFB. This specialized visceral epithelial cell contains a complex framework of cytoskeletons forming foot processes and mediate important cell signaling to maintain podocyte health. In this review, we will focus on slit diaphragm proteins such as nephrin, podocin, TRPC6/5, as well as cytoskeletal proteins Rho/small GTPases and synaptopodin and their respective roles in participating in the pathogenesis of proteinuric kidney diseases. Furthermore, we will summarize the potential therapeutic options targeting the podocyte to treat this group of kidney diseases.

20.
Adv Chronic Kidney Dis ; 25(2): 166-180, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29580581

RESUMO

Diabetic kidney disease, commonly termed diabetic nephropathy (DN), is the most common cause of end-stage kidney disease (ESKD) worldwide. The characteristic histopathology of DN includes glomerular basement membrane thickening, mesangial expansion, nodular glomerular sclerosis, and tubulointerstitial fibrosis. Diabetes is associated with a number of metabolic derangements, such as reactive oxygen species overproduction, hypoxic state, mitochondrial dysfunction, and inflammation. In the past few decades, our knowledge of DN has advanced considerably although much needs to be learned. The traditional paradigm of glomerulus-centered pathophysiology has expanded to the tubule-interstitium, the immune response and inflammation. Biomarkers of proximal tubule injury have been shown to correlate with DN progression, independent of traditional glomerular injury biomarkers such as albuminuria. In this review, we summarize mechanisms of increased susceptibility to acute kidney injury in diabetes mellitus and the roles played by many kidney cell types to facilitate maladaptive responses leading to chronic and end-stage kidney disease.


Assuntos
Injúria Renal Aguda , Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Falência Renal Crônica , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/fisiopatologia , Progressão da Doença , Humanos , Falência Renal Crônica/diagnóstico , Falência Renal Crônica/etiologia , Falência Renal Crônica/fisiopatologia
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