Abstract: TH-PO583

Kidney Glycosphingolipidomics and Metabolomics Reveal Metabolic Crosstalk between Elevated Glycosphingolipids and Glucose Metabolisms in PKD Progression

Session Information

Category: Genetic Diseases of the Kidney

  • 801 Cystic Kidney Diseases

Authors

  • Nakajima, Kazuki, Fujita Academy, Fujita health university, Toyoake, Aichi, Japan
  • Takahashi, Kazuo, Fujita Health University School of Medicine, Toyoake, Aichi-Ken, Japan
  • Kugita, Masanori, Fujita Health University, Toyoake, Aichi, Japan
  • Nagao, Shizuko, Fujita Health University, Toyoake, Aichi, Japan
  • Yuzawa, Yukio, Fujita Health University School of Medicine , Toyoake, aichi-ken, Japan
Background

Polycystic kidney diseases (PKDs) are characterized by abnormal proliferation and cyst formation in renal epithelial cells. Particularly, abnormal glucose and lipid metabolism are known therapeutic targets of PKD. We previously reported that a crucial cellular energy sensor, AMP-activated protein kinase, tightly regulates glycosphingolipid (GSL) biosynthesis by reducing nucleotide sugars, suggesting a metabolic crosstalk between GSLs and glucose metabolism (Ishibashi. Y et al. J.Biol.Chem. 2015). Herein, we investigated whether this crosstalk leads to cooperative effects in PKD progression by using lipidomics and metabolomics.

Methods

Glycosphingolipidomics and metabolomics in 10-week-old male juvenile cystic kidney (JCK) mice and control mice were performed by four newly developed methods using liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). This study included the (1) global analysis of abundant sphingolipids, (2) quantification of glucosylceramides using an isometric separation system, and (3) acidic GSLs-focused analysis. Moreover, (4) metabolomics included the quantification of nucleotide sugars, the substrate of GSLs. The involvement of the crosstalk in PKD progression was demonstrated by analyzing changes in cell lines treated with several inhibitors.

Results

Global analysis of sphingolipids revealed no significant changes in more than 100 species of abundant ceramides and sphingomyelins. However, the second method showed higher levels of major GlcCer species in the PKD mouse kidney. Further, acidic GSL-focused analysis showed a remarkable increase in GM3 gangliosides, but not sulfatides. Metabolomics revealed that the UDP-glucose level was up-regulated in PKD.
The elevated GSL levels were abrogated by treatment with 2-deoxy-glucose, an inhibitor of glucose metabolism. Conversely, treatment with Genz-123346, an inhibitor of GSL synthesis, suppressed UDP-glucose levels in a PKD model cell line.

Conclusion

The metabolic crosstalk between GSL and glucose metabolism may play a role in PKD progression. Our workflow provides valuable information regarding the molecular mechanisms studied during the search of novel therapeutic targets of PKD.