Biology subjects

Sanchez-Bayuela, T.

Publications and source records attributed to Sanchez-Bayuela, T..

3 recordsLinked to original sources

bioRxiv2025

Glycolysis and hexosamine biosynthesis pathways are key for inflammatory protein maturation and leukocyte adhesion to human aortic valve cells

Inflammation and metabolism reprogramming are hallmarks of calcific aortic valve disease (CAVD). Recent studies link inflammation to hyperglycolysis and calcification in valve interstitial cells (VICs). The metabolism of valve endothelial cells (VECs) has received less attention despite both resident valve cells are exposed to alike inflammatory clues involved in the biosynthesis of pathologically relevant glycoproteins during the early stages of CAVD. On this basis, we investigated the outcomes of glucose metabolism rewiring on glycoprotein maturation and immune cell adhesion in human resident valve cells. Real-time metabolic analysis revealed that basal VECs are more glycolytic than VICs. Also, VECs and VICs exposed to inflammatory stimuli exhibited a distinct rewiring, with VECs shifting to a more energetic metabolism, despite a similar upregulation of glycolytic genes. Blunting glucose metabolism in VICs and VECs inhibited inflammatory routes canonically associated with glycolysis, and the expression of proteins associated to the inflammatory response like interleukin-6 and cyclooxigenase-2. Moreover, Western blot and adhesion assays revealed that glycolysis is necessary for the expression and post-translational modifications of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1, and the ensuing process of monocyte-VECs adhesion. Notably, inhibition of the hexosamine biosynthetic pathway using DON and of N-glycosylation by tunicamycin, further disrupted adhesion molecule maturation and monocyte-VECs adhesion. In conclusion, glycolysis and its side-branch route the hexosamine biosynthesis pathway are necessary for nutrient-driven post-translational modifications of inflammatory proteins in inflamed valve cells and the subsequent process of monocyte-VECs adhesion that plays a key role in the initial stages of CAVD pathogenesis. NEW & NOTEWORTHYThe study uncovers a relevant role of glycolysis and its side-branch route the hexosamine biosynthesis pathway in sugar-driven post-translational modifications that are critical for the proper function of leukocyte adhesion molecules and other relevant proinflammatory molecules in aortic valve cells. These events are essential for the recruitment of cells of the monocytic lineage to aortic valve leaflets in the initial stages of calcific aortic valve disease. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=166 SRC="FIGDIR/small/693904v1_ufig1.gif" ALT="Figure 1"> View larger version (27K): org.highwire.dtl.DTLVardef@1211b22org.highwire.dtl.DTLVardef@7c5df7org.highwire.dtl.DTLVardef@fd0da2org.highwire.dtl.DTLVardef@18a40a1_HPS_FORMAT_FIGEXP M_FIG C_FIG

biochemistry↗

bioRxiv2025

Aortic Valve Remodeling in Chronic Kidney Disease: A Mineralocorticoid Receptor-Driven Mechanism Involving NGAL and TLR4 Pathways

INTRODUCTIONAortic stenosis (AS) is the most prevalent valve heart disease. Renal failure increases the risk of AS and many circulating factors released during chronic kidney disease (CKD) participate to AS pathophysiology. We assessed in this study the role of increased aldosterone levels occurring in CKD as well as MR signaling and its interplay with Neutrophil Gelatinase-Associated Lipocalin (NGAL) in aortic valve interstitial cells (VICs) pathophysiology. METHODSWe conducted in vivo studies using a CKD rat model, including both wild-type (WT) and NGAL knockout (KO-NGAL) animals, for subsequent ex vivo analysis of aortic valves. In parallel, primary rat VICs were used in vitro to assess osteogenic, fibrotic, and inflammatory responses to aldosterone, as well as to identify the key signaling pathways involved. qPCR, Western blot, and ELISA were employed to characterize these pathways. RESULTSOur findings demonstrate that MR signaling plays a central role in AS progression during CKD, as well as in VIC differentiation, inflammation, fibrosis, and calcification, mediated via the TLR4-MyD88 innate immunity pathway in aldosterone-induced responses. Furthermore, NGAL was shown to act downstream of MR to activate TLR4, promoting additional remodeling and calcification in aortic valves and VICs. These results were further validated in human samples from CKD patients. CONCLUSIONOverall, this study identifies a novel signaling pathway in AS pathophysiology in the CKD rat model and in vitro systems, highlighting for the first time the interplay between MR, NGAL, and TLR4 in driving the pathological processes underlying AS in CKD. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=169 HEIGHT=200 SRC="FIGDIR/small/675970v1_ufig1.gif" ALT="Figure 1"> View larger version (31K): org.highwire.dtl.DTLVardef@c91353org.highwire.dtl.DTLVardef@113b9d4org.highwire.dtl.DTLVardef@d4437org.highwire.dtl.DTLVardef@f9a617_HPS_FORMAT_FIGEXP M_FIG https://BioRender.com/j7vufds C_FIG

pathology↗

bioRxiv2025

NGAL drives cardiac dysfunction and fibrosis in rats with chronic kidney disease

BackgroundPatients with chronic kidney disease (CKD) are at high risk of cardiovascular (CV) complications. Neutrophil gelatinase-associated lipocalin (NGAL) is a well established marker of kidney injury, but recent evidence suggests that NGAL might also play an active in the progression of the cardiorenal syndrome. MethodsCKD was induced in rats via 5/6 nephrectomy in wild-type (WT) and Ngal-knockout (KO) rats. Cardiorenal functions were assessed three months after subtotal nephrectomy or sham operation. Cardiac fibroblasts (CFs) were incubated with or without recombinant Ngal and galectin-3 (Gal-3). ResultsCardiac function, including diastolic hemodynamics and perfusion, was less impaired in CKD Ngal KO than in CKD WT. Cardiac fibrosis was more severe in CKD WT than sham, but was blunted in CKD Ngal KO rats. Levels of Gal-3, collagen I, MCP-1 and IL-6 were elevated in cardiac fibroblasts incubated with recombinant Ngal. A similar pattern was observed in cells treated with recombinant Gal-3. Both Ngal and Gal-3 induced activation of the Tlr4-Myd88 pathway. Using Gal-3 or Tlr4 inhibitors, we showed that Gal-3 contributes to Ngal-induced cardiac fibrosis and inflammation by activating the Tlr4-Myd88 pathway. In patients with heart failure with preserved ejection fraction (HFpEF) (MEDIA-DHF and BIOSTAT-CHF cohorts), elevated levels of NGAL and Gal-3 were associated with pulmonary artery systolic pressure, a marker of advanced diastolic dysfunction and adverse clinical outcomes, particularly among patients with impaired renal function. ConclusionIn non-diabetic CKD rats, Ngal was involved in the progression of diastolic dysfunction via a Gal-3/Tlr4-dependent pathway increasing inflammation and fibrosis.

pathology↗