Caloric restriction reduces proteinuria in male rats with established nephropathy

• Published in: Physiological reports Vol. 12; no. 5; p. e15942
• Main Authors: Sijbesma, J W A, van Waarde, A, Klooster, A, Kion, I, Slart, R H J A, Lammertsma, A A, Giacobbo, B Lima, Boersma, H H, Dierckx, R A J O, van Goor, H, Bakker, S J L
• Format: Journal Article
• Language: English
• Published: United States John Wiley & Sons, Inc 01-03-2024; John Wiley and Sons Inc; Wiley
• Subjects: 13[N]ammonia PET; Age; Ammonia; Animals; Blood Pressure; Caloric Restriction; Creatinine; Diet; Dietary restrictions; Excretion; Kidney Diseases; Male; Nephropathy; Original; Oxidative stress; Positron emission tomography; protein excretion; Proteins; Proteinuria; Rats; Smooth muscle; Urine; United Kingdom > UK; United States > US; Netherlands; caloric restriction; proteinuria; protein excretion; 13[N]ammonia PET
• ISSN: 2051-817X
• DOI: 10.14814/phy2.15942

Reducing proteinuria is a crucial approach in preventing kidney function loss. Previous preclinical studies indicated that caloric restriction (CR) imposed at a young age protects against age-related proteinuria. However, these studies have not explored CR in established renal disease. Therefore, this study aimed to investigate the impact of CR on established proteinuria. Rats, aged 12 ± 2 weeks, were administered 2.1 mg/kg of Adriamycin. Six weeks after injection, protein excretion was measured, and a [
N]ammonia positron emission tomography (PET) scan was conducted to assess kidney perfusion. After 7 weeks rats were divided into four groups: ad libitum (AL) and CR groups fed either a 12% or a 20% protein diet. All groups were treated for 12 weeks. Blood pressure was measured and a second PET scan was acquired at the end of the study. The animals subjected to CR exhibited a 20.3% decrease in protein excretion (p = 0.003) compared to those in the AL groups. Additionally, blood pressure in the CR group was 21.2% lower (p < 0.001) than in the AL groups. While kidney function declined over time in all groups, the 20% CR group demonstrated the smallest decline. Thus CR effectively reduces urinary protein excretion and lowers blood pressure in rats with established proteinuria.