Abstract: FR-PO630
Clusterin Is Increased in Glomeruli of Patients with Diabetic Nephropathy and after Induction of Damage in Podocytes In Vitro
Session Information
- Diabetes Mellitus and Obesity: Basic - Experimental - II
November 03, 2017 | Location: Hall H, Morial Convention Center
Abstract Time: 10:00 AM - 10:00 AM
Category: Diabetes
- 501 Diabetes Mellitus and Obesity: Basic - Experimental
Authors
- He, Junling, Leiden University Medical Center, Leiden, Netherlands
- Bus, Pascal, Leiden University Medical Center, Leiden, Netherlands
- Veraar, Kimberley, Leiden University Medical Center, Leiden, Netherlands
- Scharpfenecker, Marion, Leiden University Medical Center, Leiden, Netherlands
- Bruijn, Jan A., Leiden University Medical Center, Leiden, Netherlands
- Baelde, Hans J., Leiden University Medical Center, Leiden, Netherlands
Background
Clusterin is a glycoprotein which is ubiquitously expressed in many tissues, including the kidney. It is demonstrated that clusterin plays a role in apoptotic processes, and it is suggested to have protective properties on cells. The expression of clusterin has been reported to be up-regulated in diverse kidney injuries. In this study, we investigated whether clusterin is upregulated in glomeruli of diabetic nephropathy (DN), where clusterin is expressed in the glomeruli, and how clusterin is regulated under diabetic conditions.
Methods
Clusterin mRNA analysis was performed on kidney cortex and micro-dissected glomeruli from patients with DN (n=24), non-diabetic subjects were used as control (n=11). Clusterin protein expression was assessed by immunohistochemistry on renal tissue from patients with DN and non-diabetic subjects. Kidneys of streptozotocin-induced diabetic mice(n=10) and non-diabetic control mice (n=10) were sequentially stained for clusterin and WT1 (a podocyte marker). Furthermore, human podocytes (Moin Saleem, Bristol, UK) were cultured and incubated with glucose, VEGF-A, angiotensin II and puromycin aminonucleoside (PAN). qPCR was performed to investigate the regulation of clusterin under these diabetic conditions.
Results
Compared to non-diabetic subjects, clusterin mRNA expression was significantly increased in both glomeruli (2.3 times) and whole kidney lysates (3.6 times) of patients with DN (p<0.05). Clusterin protein levels were also increased in glomeruli of patients with DN compared to non-diabetic subjects(p<0.05). Similar results were found in glomeruli of diabetic mice compared to non-diabetic control mice (p<0.05). Interestingly, clusterin partly co-localised with WT-1 in glomeruli of mice. Glucose, VEGF-A, and angiotensin II stimulation did not increase the clusterin mRNA expression in podocytes, whereas PAN-stimulation significantly increased the clusterin mRNA expression (p<0.05) in vitro.
Conclusion
Our data show that clusterin is increased in glomeruli of patients with DN and in podocytes after PAN-induced damage in vitro. Further studies have to elucidate whether clusterin has protective effects on podocytes upon damage during the development of DN.