Related Experiment Video
Updated: Sep 21, 2025
Mechanism of Kemeng Fang's Inhibition of Podocyte Apoptosis in Rats with Membranous Nephropathy through the PI3K/AKT Signaling Pathway
Published on: August 23, 2024
Podocyte specific deletion of PKM2 ameliorates LPS-induced podocyte injury through beta-catenin
Mohammed Alquraishi1,2, Samah Chahed1, Dina Alani1
1Department of Nutrition, The University of Tennessee Knoxville, 1215 Cumberland Avenue, 229 Jessie Harris Building, Knoxville, TN, 37996-0840, USA.
Background:
Acute kidney injury (AKI) is associated with a severe decline in kidney function caused by abnormalities within the podocytes' glomerular matrix. Recently, AKI has been linked to alterations in glycolysis and the activity of glycolytic enzymes, including pyruvate kinase M2 (PKM2). However, the contribution of this enzyme to AKI remains largely unexplored.
Methods:
Cre-loxP technology was used to examine the effects of PKM2 specific deletion in podocytes on the activation status of key signaling pathways involved in the pathophysiology of AKI by lipopolysaccharides (LPS). In addition, we used lentiviral shRNA to generate murine podocytes deficient in PKM2 and investigated the molecular mechanisms mediating PKM2 actions in vitro.
Results:
Specific PKM2 deletion in podocytes ameliorated LPS-induced protein excretion and alleviated LPS-induced alterations in blood urea nitrogen and serum albumin levels. In addition, PKM2 deletion in podocytes alleviated LPS-induced structural and morphological alterations to the tubules and to the brush borders. At the molecular level, PKM2 deficiency in podocytes suppressed LPS-induced inflammation and apoptosis. In vitro, PKM2 knockdown in murine podocytes diminished LPS-induced apoptosis. These effects were concomitant with a reduction in LPS-induced activation of β-catenin and the loss of Wilms' Tumor 1 (WT1) and nephrin. Notably, the overexpression of a constitutively active mutant of β-catenin abolished the protective effect of PKM2 knockdown. Conversely, PKM2 knockdown cells reconstituted with the phosphotyrosine binding-deficient PKM2 mutant (K433E) recapitulated the effect of PKM2 depletion on LPS-induced apoptosis, β-catenin activation, and reduction in WT1 expression.
Conclusions:
Taken together, our data demonstrates that PKM2 plays a key role in podocyte injury and suggests that targetting PKM2 in podocytes could serve as a promising therapeutic strategy for AKI.
Trial Registration:
Not applicable. Video abstract.
Insights
Targeting pyruvate kinase M2 (PKM2) in podocytes may treat acute kidney injury (AKI). Deleting PKM2 in podocytes protected against LPS-induced kidney damage, inflammation, and apoptosis by modulating the β-catenin pathway.
Area of Science:
- Nephrology
- Molecular Biology
- Biochemistry
Background:
- Acute kidney injury (AKI) involves podocyte dysfunction and altered glycolysis.
- Pyruvate kinase M2 (PKM2), a glycolytic enzyme, has a largely unexplored role in AKI.
Purpose of the Study:
- To investigate the role of PKM2 in podocyte injury during AKI.
- To explore PKM2's contribution to lipopolysaccharide (LPS)-induced AKI pathophysiology.
Main Methods:
- Utilized Cre-loxP technology for specific PKM2 deletion in podocytes.
- Employed lentiviral shRNA for PKM2 knockdown in murine podocytes for in vitro studies.
- Examined signaling pathways, including β-catenin, WT1, and nephrin.
Main Results:
- PKM2 deletion in podocytes ameliorated LPS-induced kidney dysfunction and proteinuria.
- PKM2 deficiency reduced LPS-induced inflammation, apoptosis, and podocyte structural damage.
- PKM2 knockdown suppressed LPS-induced β-catenin activation and loss of WT1/nephrin.
Conclusions:
- PKM2 plays a critical role in podocyte injury in AKI.
- Targeting PKM2 in podocytes presents a potential therapeutic strategy for AKI.
