The hepatocyte nuclear factor (HNF) family regulates complex networks of metabolism and organ development. Human mutations in its prototypical member HNF1A cause maturity-onset diabetes of the young (MODY) type 3. In this study, we identified an important role for HNF1A in the preservation of erythrocyte membrane integrity, calcium homeostasis, and osmotic resistance through an as-yet unrecognized link of HNF1A to sphingolipid homeostasis. HNF1A mice displayed microcytic hypochromic anemia with reticulocytosis that was partially compensated by avid extramedullary erythropoiesis at all erythroid stages in the spleen thereby excluding erythroid differentiation defects. Morphologically, HNF1A erythrocytes resembled acanthocytes and displayed increased phosphatidylserine exposure, high intracellular calcium, and elevated osmotic fragility. Sphingolipidome analysis by mass spectrometry revealed substantial and tissue-specific sphingolipid disturbances in several tissues including erythrocytes with the accumulation of sphingosine as the most prominent common feature. All HNF1A erythrocyte defects could be simulated by exposure of wild-type (WT) erythrocytes to sphingosine in vitro and attributed in part to sphingosine-induced suppression of the plasma-membrane Ca-ATPase activity. Bone marrow transplantation rescued the anemia phenotype in vivo, whereas incubation with HNF1A plasma increased the osmotic fragility of WT erythrocytes in vitro. Our data suggest a non-cell-autonomous erythrocyte defect secondary to the sphingolipid changes caused by HNF1A deficiency. Transcriptional analysis revealed 4 important genes involved in sphingolipid metabolism to be deregulated in HNF1A deficiency: , sphingosine kinase-2, neutral ceramidase, and ceramide synthase-5. The considerable erythrocyte defects in murine HNF1A deficiency encourage clinical studies to explore the hematological consequences of HNF1A deficiency in human MODY3 patients.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1182/blood-2017-03-774356 | DOI Listing |
Mol Med Rep
February 2025
Department of Gastroenterology, Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China.
Nat Immunol
December 2024
Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences (IMS), Yokohama, Japan.
Genetic studies in mice have shown that the zinc finger transcription factor BCL11B has an essential role in regulating early T cell development and neurogenesis. A de novo heterozygous missense BCL11B variant, BCL11B, was isolated from a patient with T cell deficiency and neurological disorders. Here, we show that mice harboring the corresponding Bcl11b mutation show the emergence of natural killer (NK)/group 1 innate lymphoid cell (ILC1)-like NKp46 cells in the thymus and reduction in TBR1 neurons in the neocortex, which are observed with loss of Bcl11a but not Bcl11b.
View Article and Find Full Text PDFNat Immunol
October 2024
Department of Cardiothoracic Surgery, Weill Cornell Medicine, New York, NY, USA.
TCF1 progenitor CD8 T cells mediate the efficacy of immunotherapy; however, the mechanisms that govern their generation and maintenance are poorly understood. Here, we show that targeting glycolysis through deletion of pyruvate kinase muscle 2 (PKM2) results in elevated pentose phosphate pathway (PPP) activity, leading to enrichment of a TCF1 progenitor-exhausted-like phenotype and increased responsiveness to PD-1 blockade in vivo. PKM2 CD8 T cells showed reduced glycolytic flux, accumulation of glycolytic intermediates and PPP metabolites and increased PPP cycling as determined by 1,2-C glucose carbon tracing.
View Article and Find Full Text PDFJ Exp Med
October 2024
Stem Cell and Cancer Biology Laboratory, The Francis Crick Institute, London, UK.
Intestinal stem cells at the crypt divide and give rise to progenitor cells that proliferate and differentiate into various mature cell types in the transit-amplifying (TA) zone. Here, we showed that the transcription factor ARID3A regulates intestinal epithelial cell proliferation and differentiation at the TA progenitors. ARID3A forms an expression gradient from the villus tip to the upper crypt mediated by TGF-β and WNT.
View Article and Find Full Text PDFTo understand the role of T cells in the pathogenesis of ulcerative colitis (UC), we analyzed colonic T cells isolated from patients with UC and controls. Here we identified colonic CD4 and CD8 T lymphocyte subsets with gene expression profiles resembling stem-like progenitors, previously reported in several mouse models of autoimmune disease. Stem-like T cells were increased in inflamed areas compared to non-inflamed regions from the same patients.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!