American Journal of Physiology - Regulatory, Integrative and Comparative Physiology Published 1 August 2015 Vol. 309 no. 3, R215-R222 DOI: 10.1152/ajpregu.00526.2014
Weverton M. Luchi, Maria Heloisa M. Shimizu, Daniele Canale, Pedro Henrique F. Gois, Ana Carolina de Bragança, Rildo A. Volpini, Adriana C. C. Girardi, Antonio C. Seguro
Vitamin D deficiency (VDD) is widespread in the general population. Iodinated (IC) or gadolinium-based contrast media (Gd) may decrease renal function in high-risk patients.
This study tested the hypothesis that VDD is a predisposing factor for IC- or Gd-induced nephrotoxicity
. To this end, male Wistar rats were fed standard (SD) or vitamin D-free diet for 30 days. IC (diatrizoate), Gd (gadoterate meglumine), or 0.9% saline was then administered intravenously and six groups were obtained as the following: SD plus 0.9% saline (Sham-SD), SD plus IC (SD+IC), SD plus Gd (SD+Gd), vitamin D-free diet for 30 days plus 0.9% saline (Sham-VDD30), vitamin D-free diet for 30 days plus IC (VDD30+IC), and vitamin D-free diet for 30 days plus Gd (VDD30+Gd). Renal hemodynamics, redox status, histological, and immunoblot analysis were evaluated 48 h after contrast media (CM) or vehicle infusion. VDD rats showed lower levels of total serum 25-hydroxyvitamin D [25(OH)D], similar plasma calcium and phosphorus concentration, and higher renal renin and angiotensinogen protein expression compared with rats fed SD. IC or Gd infusion did not affect inulin clearance-based estimated glomerular filtration rate (GFR) in rats fed SD but significantly decreased GFR in rats fed vitamin D-free diet. Both CM increased renal angiotensinogen, and the interaction between VDD and CM triggered lower renal endothelial nitric oxide synthase abundance and higher renal thiobarbituric acid reactive substances-to-glutathione ratio (an index of oxidative stress) on VDD30+IC and VDD30+Gd groups. Conversely, worsening of renal function was not accompanied by abnormalities on kidney structure. Additionally, rats on a VDD for 60 days displayed a greater fall in GFR after CM administration. Collectively, our findings suggest that VDD is a potential risk factor for IC- or Gd-induced nephrotoxicity most likely due to imbalance in intrarenal vasoactive substances and oxidative stress.
Contrast-induced nephropathy: Definition, epidemiology, and patients at risk 2006 – free text on-line
- “Contrast media (CM) are increasingly used in diagnostic and interventional procedures. This results in the rising incidence of iatrogenic renal function impairment caused by the exposure to CM, a condition known as CIN. Radiographic CM are responsible for 11% of cases of hospital-acquired renal insufficiency, . . “
- ”An overall incidence of CIN in the general population is reported to be 0.6–2.3%”
- ” Non-modifiable risk factors include pre-existent renal insufficiency, diabetes mellitus, older age, reduced left ventricle systolic function, advanced heart failure, acute myocardial infarction, and shock, while volume and type of CM, concomitant use of nephrotoxic medications, hypotension, dehydration, hypoalbuminemia, anemia, and the use of intra-aortic balloon pump (IABP) represent the modifiable risk factors for CIN.”
- Vitamin D is not mentioned