bioRxiv Science⌕ Search

bioRxiv · 10.1101/2023.08.22.554242

WWP2 MEDIATES THE METABOLIC REPROGRAMMING OF RENAL MYOFIBROBLASTS TO PROMOTE KIDNEY FIBROSIS

Abstract

Renal fibrosis is a common pathological endpoint in chronic kidney disease (CKD) that is challenging to reverse. Although myofibroblasts are mainly responsible for the accumulation of a fibrillar collagen-rich extracellular matrix (ECM) in fibrotic kidney, recent studies have unveiled their diversity in terms of proliferative and fibrotic characteristics. This diversity could be linked with the existence of different metabolic states, and myofibroblast metabolic reprogramming may contribute to the pathogenesis and progression of renal fibrosis. Here, we reveal an unexpected role of the E3 ubiquitin-protein ligase WWP2 in the metabolic reprogramming of myofibroblasts during renal fibrosis. The tubulointerstitial expression of WWP2 contributes to the progression of fibrosis in CKD patients, and in pre-clinical murine models of CKD. WWP2 deficiency increases fatty acid oxidation and activates the pentose phosphate pathway, boosting mitochondrial respiration at the expense of glycolysis. This concurrently promotes myofibroblast proliferation and halts pro-fibrotic activation, reducing the severity of kidney fibrosis. Mechanistically, WWP2 suppresses the transcription of PGC-1, a metabolic mediator shaping myofibroblast fibrotic response. Pharmacological interventions targeting PGC-1 reverse the effects of WWP2 on fibrotic myofibroblasts. These findings demonstrate the influence of WWP2 on essential metabolic pathways involved in fibrogenesis, uncovering the WWP2-PGC-1 axis that orchestrates the metabolic reprogramming of myofibroblasts during renal fibrosis. Our study presents a potential novel target for therapeutic intervention in the treatment of chronic kidney disease. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=177 HEIGHT=200 SRC="FIGDIR/small/554242v1_ufig1.gif" ALT="Figure 1"> View larger version (52K): org.highwire.dtl.DTLVardef@1847ffeorg.highwire.dtl.DTLVardef@1ef029aorg.highwire.dtl.DTLVardef@93e0f1org.highwire.dtl.DTLVardef@950d49_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LIWWP2 expression is elevated in the tubulointerstitium of fibrotic kidneys and contributes to CKD pathogenesis and progression. C_LIO_LIWWP2 uncouples the pro-fibrotic activation and cell proliferation in renal myofibroblasts. C_LIO_LIWWP2 controls mitochondrial respiration in renal myofibroblasts through the metabolic regulator PGC-1 C_LIO_LIMyofibroblast metabolic reprogramming mediates the effect of WWP2 on fibrotic myofibroblasts. C_LI

Source connections

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Chen, H., You, R., Guo, J., Zhou, W., Chew, G., Devapragash, N., Loh, J. Z., Gesualdo, L., Li, Y., Jiang, Y., Tan, E. L. S., Chen, S., Pontrelli, P., Pesce, F., Behmoaras, J., Zhang, A., Petretto, E. G.. 2023-08-22. WWP2 MEDIATES THE METABOLIC REPROGRAMMING OF RENAL MYOFIBROBLASTS TO PROMOTE KIDNEY FIBROSIS. https://doi.org/10.1101/2023.08.22.554242

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

Functional characterization of Rho GTPase activating proteins SYDE1 and SYDE2

The human genome encodes more than 60 proteins containing Rho GTPase activating protein (RhoGAP) domains, many of which remain understudied with respect to their target specificity and biological roles. SYDE1 and SYDE2 are two such orphan RhoGAPs, for which there are few studies characterizing their biochemical and cellular functions and conflicting reports identifying their cognate GTPases. We previously identified SYDE1 and SYDE2 in a screen for substrates of the c-Jun N-terminal kinases. Here, we show that SYDE1 and SYDE2 are preferentially phosphorylated by JNK1 relative to other mitogen-activated protein kinases (MAPKs) at sites proximal to a kinase docking region. Purified SYDE1 and SYDE2 are shown to have significant catalytic GAP activity toward RhoA, Rac1, and Cdc42. However, neither up- nor down-regulation of SYDE1/2 expression leads to detectable changes in bulk GTP loading of any of these GTPases. Nevertheless, we demonstrate that SYDE1 and SYDE2, in a partially GAP-dependent manner, increase cell spreading and number of focal adhesions, and promote more directionally persistent migration in HEK293 cells. Together, these findings establish SYDE1 and SYDE2 as robust JNK substrates with catalytic activity toward a set of Rho GTPases and reveal basic functions of SYDE1 and SYDE2 in regulating cell morphology, adhesion, and migration.

cell biology↗

The filopodial scaffold polyphosphate dictates cell adhesion-versus-invasion decisions

Inorganic polyphosphate (polyP) is an ancient polymer conserved across all life, serving cell type and location specific functions in every major compartment. Yet its role at the plasma membrane, where it accumulates to peak levels in many primary cells, is largely unknown. Here we identify polyP as a stabilizing component of filopodia, actin based membrane protrusions that govern cell adhesion, contact inhibition, and chemotaxis. Elevating cellular polyP increases filopodial stability and enhances cell adhesion, whereas reducing polyP accelerates filopodial disassembly and promotes cell migration. Mechanistically, we find that polyP acts as a structural filopodial scaffold, recruiting and organizing IRSp53, a membrane curvature inducing protein. We show that metastatic fibroblasts and breast cancer organoids carry markedly reduced and intracellularly reorganized polyP levels relative to their non transformed counterparts. Restoring endogenous polyP via lipid nanoparticle delivery suppresses their invasive phenotypes and reverses prometastatic gene expression signatures, implicating polyP as a primordial tumor suppressor.

cell biology↗

Mitochondrial transfer mediates metabolic communication between beta cells and islet macrophages

Pancreatic islet macrophages support islet homeostasis and adapt their metabolic program in response to environmental cues, including beta cell released factors. Intercellular mitochondrial transfer is a biological process that modulates cellular responses. To test whether beta cells, which are strongly secretory, transfer mitochondria to islet macrophages, we generated mice with beta cell-specific expression of mitochondrial GFP (PhAMfloxIns1Cre). We demonstrate that beta cells transfer mitochondria to islet macrophages in vivo and in vitro. Diabetogenic stressors did not alter the frequency of mitochondrial transfer and macrophages containing beta cell-derived GFP exhibit increased protein synthesis rates. RNA-seq identified upregulation of activity-regulated cytoskeleton associated protein (Arc) in macrophages receiving beta cell-derived mitochondria, while disruption of actin cytoskeleton dynamics prevented mitochondrial transfer. Together, these findings identify mitochondrial transfer as a previously unrecognized mechanism of beta cell-macrophage communication that may contribute to islet homeostasis and immune regulation.

cell biology↗