Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 6 de 6
Filter
Add more filters











Database
Language
Publication year range
1.
Kidney Int ; 102(5): 1042-1056, 2022 11.
Article in English | MEDLINE | ID: mdl-35931300

ABSTRACT

Defective DNA repair pathways contribute to the development of chronic kidney disease (CKD) in humans. However, the molecular mechanisms underlying DNA damage-induced CKD pathogenesis are not well understood. Here, we investigated the role of tubular cell DNA damage in the pathogenesis of CKD using mice in which the DNA repair protein Fan1 was knocked out. The phenotype of these mice is orthologous to the human DNA damage syndrome, karyomegalic interstitial nephritis (KIN). Inactivation of Fan1 in kidney proximal tubule cells sensitized the kidneys to genotoxic and obstructive injury characterized by replication stress and persistent DNA damage response activity. Accumulation of DNA damage in Fan1 tubular cells induced epithelial dedifferentiation and tubular injury. Characteristic to KIN, cells with chronic DNA damage failed to complete mitosis and underwent polyploidization. In vitro and in vivo studies showed that polyploidization was caused by the overexpression of DNA replication factors CDT1 and CDC6 in FAN1 deficient cells. Mechanistically, inhibiting DNA replication with Roscovitine reduced tubular injury, blocked the development of KIN and mitigated kidney function in these Fan1 knockout mice. Thus, our data delineate a mechanistic pathway by which persistent DNA damage in the kidney tubular cells leads to kidney injury and development of CKD. Furthermore, therapeutic modulation of cell cycle activity may provide an opportunity to mitigate the DNA damage response induced CKD progression.


Subject(s)
Nephritis, Interstitial , Renal Insufficiency, Chronic , Animals , Humans , Mice , DNA Damage , DNA Repair , Endodeoxyribonucleases/genetics , Endodeoxyribonucleases/metabolism , Exodeoxyribonucleases/genetics , Exodeoxyribonucleases/metabolism , Fibrosis , Kidney/pathology , Mice, Knockout , Multifunctional Enzymes/genetics , Multifunctional Enzymes/metabolism , Nephritis, Interstitial/pathology , Renal Insufficiency, Chronic/etiology , Roscovitine
2.
Sci Rep ; 12(1): 4953, 2022 03 23.
Article in English | MEDLINE | ID: mdl-35322081

ABSTRACT

Placental function requires organized growth, transmission of nutrients, and an anti-inflammatory milieu between the maternal and fetal interface, but placental factors important for its function remain unclear. Renalase is a pro-survival, anti-inflammatory flavoprotein found to be critical in other tissues. We examined the potential role of renalase in placental development. PCR, bulk RNA sequencing, immunohistochemistry, and immunofluorescence for renalase and its binding partners, PMCA4b and PZP, were performed on human placental tissue from second-trimester and full-term placentas separated into decidua, placental villi and chorionic plates. Quantification of immunohistochemistry was used to localize renalase across time course from 17 weeks to term. Endogenous production of renalase was examined in placental tissue and organoids. Renalase and its receptor PMCA4b transcripts and proteins were present in all layers of the placenta. Estimated RNLS protein levels did not change with gestation in the decidual samples. However, placental villi contained more renalase immunoreactive cells in fetal than full-term placental samples. RNLS co-labeled with markers for Hofbauer cells and trophoblasts within the placental villi. Endogenous production of RNLS, PMCA4b, and PZP by trophoblasts was validated in placental organoids. Renalase is endogenously expressed throughout placental tissue and specifically within Hofbauer cells and trophoblasts, suggesting a potential role for renalase in placental development and function. Future studies should assess renalase's role in normal and diseased human placenta.


Subject(s)
Placenta , Trophoblasts , Chorionic Villi/metabolism , Decidua/metabolism , Female , Humans , Monoamine Oxidase , Placenta/metabolism , Placentation , Plasma Membrane Calcium-Transporting ATPases , Pregnancy , Trophoblasts/metabolism
3.
Development ; 149(8)2022 04 15.
Article in English | MEDLINE | ID: mdl-35050308

ABSTRACT

Maintenance of a healthy pregnancy is reliant on a successful balance between the fetal and maternal immune systems. Although the maternal mechanisms responsible have been well studied, those used by the fetal immune system remain poorly understood. Using suspension mass cytometry and various imaging modalities, we report a complex immune system within the mid-gestation (17-23 weeks) human placental villi (PV). Consistent with recent reports in other fetal organs, T cells with memory phenotypes, although rare in abundance, were detected within the PV tissue and vasculature. Moreover, we determined that T cells isolated from PV samples may be more proliferative after T cell receptor stimulation than adult T cells at baseline. Collectively, we identified multiple subtypes of fetal immune cells within the PV and specifically highlight the enhanced proliferative capacity of fetal PV T cells.


Subject(s)
Chorionic Villi/immunology , Placenta/immunology , Antigens, CD/metabolism , Antigens, Differentiation, Myelomonocytic/metabolism , B-Lymphocytes/cytology , B-Lymphocytes/immunology , B-Lymphocytes/metabolism , B7-H1 Antigen/genetics , B7-H1 Antigen/metabolism , Chorionic Villi/metabolism , Female , Fetus/immunology , Fetus/metabolism , Flow Cytometry , HLA-DR Antigens/genetics , HLA-DR Antigens/metabolism , Humans , Killer Cells, Natural/cytology , Killer Cells, Natural/immunology , Killer Cells, Natural/metabolism , Leukocyte Common Antigens/metabolism , Lymphocyte Activation , Macrophages/cytology , Macrophages/immunology , Macrophages/metabolism , Memory T Cells/cytology , Memory T Cells/immunology , Memory T Cells/metabolism , Placenta/cytology , Placenta/metabolism , Pregnancy , Pregnancy Trimester, Second , Receptors, Cell Surface/metabolism , Receptors, Chemokine/genetics , Receptors, Chemokine/metabolism , Single-Cell Analysis/methods , T-Lymphocytes/cytology , T-Lymphocytes/immunology , T-Lymphocytes/metabolism
4.
Nat Med ; 27(12): 2104-2107, 2021 12.
Article in English | MEDLINE | ID: mdl-34887578

ABSTRACT

Generation of beta cells via transdifferentiation of other cell types is a promising avenue for the treatment of diabetes. Here we reconstruct a single-cell atlas of the human fetal and neonatal small intestine. We identify a subset of fetal enteroendocrine K/L cells that express high levels of insulin and other beta cell genes. Our findings highlight a potential extra-pancreatic source of beta cells and expose its molecular blueprint.


Subject(s)
Enteroendocrine Cells/metabolism , Fetal Development , Insulin/metabolism , Humans
5.
J Exp Med ; 218(9)2021 09 06.
Article in English | MEDLINE | ID: mdl-34269788

ABSTRACT

Necrotizing enterocolitis (NEC) is a severe gastrointestinal complication of prematurity. Using suspension and imaging mass cytometry coupled with single-cell RNA sequencing, we demonstrate severe inflammation in patients with NEC. NEC mucosa could be subtyped by an influx of three distinct neutrophil phenotypes (immature, newly emigrated, and aged). Furthermore, CD16+CD163+ monocytes/Mϕ, correlated with newly emigrated neutrophils, were specifically enriched in NEC mucosa, found adjacent to the blood vessels, and increased in circulation of infants with surgical NEC, suggesting trafficking from the periphery to areas of inflammation. NEC-specific monocytes/Mϕ transcribed inflammatory genes, including TREM1, IL1A, IL1B, and calprotectin, and neutrophil recruitment genes IL8, CXCL1, CXCL2, CXCL5 and had enrichment of gene sets in pathways involved in chemotaxis, migration, phagocytosis, and reactive oxygen species generation. In summary, we identify a novel subtype of inflammatory monocytes/Mϕ associated with NEC that should be further evaluated as a potential biomarker of surgical NEC and a target for the development of NEC-specific therapeutics.


Subject(s)
Antigens, CD , Antigens, Differentiation, Myelomonocytic , Enterocolitis, Necrotizing/pathology , Gastric Mucosa/pathology , Monocytes/pathology , Receptors, Cell Surface , Receptors, IgG , Antigens, CD/genetics , Antigens, CD/metabolism , Antigens, Differentiation, Myelomonocytic/genetics , Antigens, Differentiation, Myelomonocytic/metabolism , Blood Vessels/pathology , Case-Control Studies , Chemotaxis , Enterocolitis, Necrotizing/surgery , GPI-Linked Proteins/genetics , GPI-Linked Proteins/metabolism , Humans , Infant , Infant, Newborn , Intestine, Small/blood supply , Intestine, Small/pathology , Monocytes/immunology , Neutropenia/etiology , Neutropenia/pathology , Neutrophils/pathology , Phagocytosis/physiology , Reactive Oxygen Species/metabolism , Receptors, Cell Surface/genetics , Receptors, Cell Surface/metabolism , Receptors, IgG/genetics , Receptors, IgG/metabolism , Sequence Analysis, RNA , Single-Cell Analysis
6.
JCI Insight ; 5(21)2020 11 05.
Article in English | MEDLINE | ID: mdl-33001863

ABSTRACT

Symbiotic microbial colonization through the establishment of the intestinal microbiome is critical to many intestinal functions, including nutrient metabolism, intestinal barrier integrity, and immune regulation. Recent studies suggest that education of intestinal immunity may be ongoing in utero. However, the drivers of this process are unknown. The microbiome and its byproducts are one potential source. Whether a fetal intestinal microbiome exists is controversial, and whether microbially derived metabolites are present in utero is unknown. Here, we aimed to determine whether bacterial DNA and microbially derived metabolites can be detected in second trimester human intestinal samples. Although we were unable to amplify bacterial DNA from fetal intestines, we report a fetal metabolomic intestinal profile with an abundance of bacterially derived and host-derived metabolites commonly produced in response to microbiota. Though we did not directly assess their source and function, we hypothesize that these microbial-associated metabolites either come from the maternal microbiome and are vertically transmitted to the fetus to prime the fetal immune system and prepare the gastrointestinal tract for postnatal microbial encounters or are produced locally by bacteria that were below our detection threshold.


Subject(s)
Bacteria/metabolism , Fetus/metabolism , Gastrointestinal Microbiome , Gastrointestinal Tract/metabolism , Intestines/physiology , Metabolome , Adolescent , Bacteria/genetics , Bacteria/isolation & purification , Child , DNA, Bacterial/analysis , DNA, Bacterial/genetics , Female , Fetus/microbiology , Gastrointestinal Tract/microbiology , Gestational Age , Humans , Infant , Infant, Newborn , Intestines/microbiology , Male
SELECTION OF CITATIONS
SEARCH DETAIL