Abstract: TH-PO202
The HIV Protease Inhibitor Darunavir Restores Autophagy in Kidneys of Diabetic Mice
Session Information
- Diabetic Kidney Disease: Basic - I
November 03, 2022 | Location: Exhibit Hall, Orange County Convention Center‚ West Building
Abstract Time: 10:00 AM - 12:00 PM
Category: Diabetic Kidney Disease
- 601 Diabetic Kidney Disease: Basic
Authors
- Ross, Michael J., Albert Einstein College of Medicine, Bronx, New York, United States
- Karttunen, Heidi, Albert Einstein College of Medicine, Bronx, New York, United States
- Gao, Xiaobo, Albert Einstein College of Medicine, Bronx, New York, United States
Background
Despite the success of antiretroviral therapy (ART) in improving mortality, persons with HIV have increased risk of death, and kidney disease and diabetes are important contributors to their excess mortality. Data from our laboratory demonstrate that the HIV protease inhibitor darunavir (DRV) prevents kidney disease in HIV-transgenic mice via mechanisms independent of HIV protease and also reduces albuminuria and molecular markers of kidney injury in mice with diabetic kidney disease (DKD). Since autophagy is cytoprotective against HIV and diabetes-induced kidney injury, and autophagy is reduced in the kidneys of patients with DKD, we studied the effect of DRV upon autophagy in a murine model of DKD.
Methods
eNOS-/- 9 week-old C57BL/6 mice, which develop more severe nephropathy than wild-type C57BL/6 mice, underwent induction of diabetes by administration of 5 daily 50mg/kg doses of streptozotocin (STZ) injection. 14 weeks after diabetes induction, mice were treated with either DRV (100mg/kg) or control by daily oral gavage for 4 weeks. Urinary albumin creatinine ratio (ACR) assay, immunocytochemistry, western blotting and real-time PCR were performed with routine protocols in our laboratory.
Results
STZ induced severe sustained hyperglycemia and kidney injury in eNOS-/- mice, which resulted in marked increase urine ACR, which was reduced by DRV. Western blotting and immunfluorescence studies demonstrated marked accumulation of lipidated LC3 (LC3-II) and p62 in kidneys of diabetic eNOS-/- mice, indicating reduced autophagic flux. Accumulation of LC3-II and p62 in diabetic eNOS-/- kidneys was most apparent in tubular cells. DRV treatment reduced LC3-II and p62 in diabetic eNOS-/- mice to levels that were similar to non-diabetic mice.
Conclusion
Kidneys of diabetic eNOS-/- mice had reduced autophagic flux (accumulated LC3-II and p62) compared to non-diabetic mice, which was reversed by DRV. Our previous studies demonstrated that DRV reduced albuminuria and molecular markers of glomerular and tubular injury in mice with DKD. Our data suggest that DRV may protect against DKD via normalization of autophagic flux. Since reducing albuminuria may affect autophagy in tubular cells, future studies will determine whether the effect of DRV upon autophagy is independent of its effects on albuminuria.
Funding
- NIDDK Support