Cyto-Protector Effect of a VDR Activator at the Mitochondrial Level in an Obstructive Nephropathy Model

LEÓN FERDER; WALTER MANUCHA

Denver, Colorado-EEUU

Congreso; Advancing Science and Medicine to Improve Kidney Health, 43rd Annual Meeting & Scientific Exposition; 2010

American Society of Nephrology

New evidence suggests that the activators of Vitamin D receptors have a suppressant effect on the renin angiotensin aldosterone system, as well as anti-inflammatory and anti-fibrotic effects. This study investigates, in an obstructive nephropathy animal model, the structural and functional changes in the kidney and the paricalcitol effects in this changes. Ten adult female Wistar rats were obstructed surgically at the urethero-pelvic level.  They were divided into two groups, Control and Treated.  The treatment was done for a 15-day duration, injecting intraperitoneally 30 ng/Kg/day. We evaluated blood pressure, PTH, as well as calcium and phosphorous levels. The kidney was also evaluated histologically for fibrosis with Masson trichomic staining, for apoptosis with TUNEL technique, and electronic microscopy for mitochondrial evaluation. Results: The biochemical changes in calcium, phosphorous, and PTH were not significant. Histological changes in the kidney showed that the obstructive nephropathy induced interstitial fibrosis with increase in apoptosis. Both results decreased in the animals treated with paricalcitol. Electronic microscopy revealed, in obstructed non-treated animals, electronically luminous nuclear material in the nucleus. We also noted that the mitochondria were increased in size with dilated crests and spaces in their interior. These mitochondrial changes were not present in the paricalcitol-treated animals. Conclusions: These results, in an obstructed nephropathy model, show a cyto-protected effect of the activator of Vitamin D receptors, paricalcitol, revealing for the first time a possible protective effect at the mitochondrial level.