Kidney Week

Abstract: TH-PO576

Tissue Mass Spectrometry Analysis of Glycosphingolipid Distribution in Murine Polycystic Kidney Disease

Session Information

• Cystic Kidney Diseases - I
  November 02, 2017 | Location: Hall H, Morial Convention Center
  Abstract Time: 10:00 AM - 10:00 AM

Category: Genetic Diseases of the Kidney

• 801 Cystic Kidney Diseases

Authors

• Silvescu, Cristina I, Sanofi, Waltham, Massachusetts, United States

Cristina I Silvescu,

• Guo, Lilu, Sanofi, Waltham, Massachusetts, United States

Lilu Guo,

• Smith, Laurie A., Sanofi Genzyme, Framingham, Massachusetts, United States

Laurie A. Smith,

• Cromwell, Mandy, Sanofi, Waltham, Massachusetts, United States

Mandy Cromwell,

• Bangari, Dinesh, Sanofi Genzyme, Framingham, Massachusetts, United States

Dinesh Bangari,

• Ryan, Susan, Sanofi Corporation, Framingham, Alabama, United States

Susan Ryan,

• Oliva, Petra, Sanofi Genzyme, Framingham, Massachusetts, United States

Petra Oliva,

• Kloss, Alla, Sanofi, Waltham, Massachusetts, United States

Alla Kloss,

• O'Shea, Thomas J, Sanofi, Waltham, Massachusetts, United States

Thomas J O'Shea,

• Korfmacher, Walter, Sanofi, Waltham, Massachusetts, United States

Walter Korfmacher,

• Beskrovnaya, Oxana, Sanofi Genzyme, Framingham, Massachusetts, United States

Oxana Beskrovnaya,

• Natoli, Thomas A., Sanofi, Framingham, Massachusetts, United States

Thomas A. Natoli,

Background

Elevated glucosylceramide synthase (GCS) activity is a hallmark of polycystic kidney disease (PKD), and pharmacologic or genetic reduction of glycosphingolipid (GSL) accumulation slows cyst growth and preserves kidney function in multiple models of murine PKD. To better understand the role of GSL accumulation in PKD progression, we sought to characterize spatial tissue distribution of GSLs in cystic kidneys of juvenile cystic kidney (jck) mice.

Methods

Liquid chromatography coupled to tandem mass spectrometry (LC/MS/MS) and tissue MALDI/TOF mass spectrometry imaging (MSI) were used to quantify GSL species in kidney tissue isolated from wild-type mice, jck mice, or jck mice treated with a GCS inhibitor.

Results

LC/MS/MS analysis demonstrates roughly 3- to 6-fold accumulation of Gb3, globoside, GM2, and GD3 in jck mouse kidneys compared to wild-type kidneys; these levels are all reduced following GCS inhibition. GM3 was detectable by tissue MSI in a diffuse pattern consistent with epithelial accumulation throughout the jck mouse kidney. A hydroxylated form of GM3 accumulates in blood vessels of the jck mouse kidneys. Elevated levels of GM1 species were detected in jck mouse kidneys in a patchy pattern that was distinguishable from that seen with GM3. Several sulfatide species could be detected in discrete patterns localizing to the cortex, medulla, and papilla; the C20 isoform was excluded from the papilla, while the C24 isoform was highly enriched in the papilla, and clear epithelial localization could be observed.

Conclusion

Accumulation of complex glycosphingolipids downstream of glucosylceramide is evident in cystic kidneys compared to normal kidneys, and tissue distribution of multiple GSL species can be assessed using mass spectrometry imaging. Differences in either the carbohydrate composition of the GSL or the chain length of the lipid moiety can result in localization to distinct cell types. Tissue MSI therefore provides a unique approach to better understand the role of glycosphingolipids in kidney disease.

Funding

• Commercial Support –