L-NAME Accelerates the Onset of Diabetic Nephropathy in Genetically Diabetic Mice
- Diabetic Kidney Disease: Basic - I
November 03, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Diabetic Kidney Disease
- 701 Diabetic Kidney Disease: Basic
- Nicese, Maria Novella, Leids Universitair Medisch Centrum, Leiden, Zuid-Holland, Netherlands
- Koudijs, Angela, Leids Universitair Medisch Centrum, Leiden, Zuid-Holland, Netherlands
- Lalai, Reshma, Leids Universitair Medisch Centrum, Leiden, Zuid-Holland, Netherlands
- Roelofs, Joris, Amsterdam UMC Locatie AMC, Amsterdam, Noord-Holland, Netherlands
- Bijkerk, Roel, Leids Universitair Medisch Centrum, Leiden, Zuid-Holland, Netherlands
- van den Berg, Bernard, Leids Universitair Medisch Centrum, Leiden, Zuid-Holland, Netherlands
- Rotmans, Joris I., Leids Universitair Medisch Centrum, Leiden, Zuid-Holland, Netherlands
Diabetic nephropathy (DN) represents one of the major causes of end stage kidney disease worldwide. Despite DN having such a high incidence, mouse models of DN rarely mimic all aspects of the human disease and usually show very slow development of DN phenotype. For this reason, in this project we aimed to develop an accelerated and reproducible rodent model of DN.
For our experiments we chose 9-week old female and male of the leptin receptor knock-out (BKS.Cg-Dock7m +/+ Leprdb/J) mice as type 2 diabetes model. As these mice are still not prone to develop severe kidney injury despite their diabetic condition, we administered the eNOS inhibitor L-NAME for 6 weeks, in order to aggravate kidney damage. Mice were divided in three groups: one vehicle control group, one receiving 40/mg/kg/day of L-NAME and one receiving 80/mg/kg/day of L-NAME dissolved in drinking water. Blood pressure and glomerular filtration rate (GFR) were measured, besides glycemia and albuminuria. At the end of the experiment, animals were killed and blood and organs collected.
Mice treated with 80mg/kg/day of L-NAME showed an average increase of 10 mmHg in systolic blood pressure, with a peak of 30 mmHg increase at week 4 of treatment. Despite the increased blood pressure, three weeks of L-NAME administration caused a significant reduction in GFR for both doses of L-NAME, with 5% reduction for the 40mg-group and 23% for the 80mg-group. No change in GFR was observed in the controls. This decrease in GFR was accompanied by a 10-fold increase in urinary albumin for both the experimental groups already after 3 weeks of treatment. PAS staining of kidney sections revealed that in particular mice treated with 80mg of L-NAME have enlarged glomeruli and a reduced glomerular capillary density, coinciding with mesangial expansion. Electron microscopy analysis showed that glomerular basement membrane (GBM) thickening was also occurring.
Our results show that L-NAME considerably accelerates the onset of DN in diabetic mice, with signs of kidney dysfunction already after 3 weeks. This model could be used to assess the therapeutic potential of novel interventions aimed to slow down the progression of DN.