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Updated: Oct 3, 2025
12:19
Single-channel Analysis and Calcium Imaging in the Podocytes of the Freshly Isolated Glomeruli
Published on: June 27, 2015
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Hyperglycemic environment disrupts phosphate transporter function and promotes calcification processes in podocytes
Tomasz Kulesza1, Marlena Typiak1,2, Patrycja Rachubik1
1Laboratory of Molecular and Cellular Nephrology, Mossakowski Medical Research Institute, Polish Academy of Sciences, Gdansk, Poland.
Journal of Cellular Physiology
|February 12, 2022
Summary
High glucose levels in diabetic kidney disease increase phosphate production and retention in podocytes, potentially causing soft tissue calcification. This study investigates phosphate transporters in podocytes under hyperglycemic conditions.
Area of Science:
- Nephrology
- Cell Biology
- Biochemistry
Background:
- Soft tissue calcification is common in chronic kidney disease (CKD), often linked to diabetic nephropathy and hyperphosphatemia.
- Hyperphosphatemia in CKD impairs kidney function and damages the glomerular filtration barrier (GFB), which includes podocytes.
Purpose of the Study:
- To investigate the expression and function of phosphate transporters in human podocytes under high glucose conditions.
- To determine how high glucose affects phosphate transport and metabolism in podocytes, potentially contributing to glomerular calcification.
Main Methods:
- Cultured human immortalized podocytes in high glucose (30 mM) and standard glucose (11 mM) media.
- Assessed expression of phosphate transporters (NaPi 2c, Pit 1, Pit 2, XPR1) via mRNA and protein levels.
- Measured activity of tissue nonspecific alkaline phosphatase and levels of ectonucleotide pyrophosphatase/phosphodiesterase 1.
Main Results:
- High glucose reduced expression of Pit 1 and Pit 2 phosphate transporters in podocytes.
- High glucose altered the cell membrane exposure of analyzed transporters.
- Tissue nonspecific alkaline phosphatase activity increased, leading to higher phosphate generation, while ectonucleotide pyrophosphatase/phosphodiesterase 1 decreased, reducing pyrophosphate.
Conclusions:
- Hyperglycemia enhances phosphate production and extracellular retention in podocytes.
- These changes in phosphate handling by podocytes under high glucose conditions may promote glomerular calcification in diabetic kidney disease.
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