A Contrast Examination of Proinflammatory Effects on Kidney Function for γ-Fe₂O₃ NP and Gadolinium Dimeglumine

Contrast-enhanced magnetic resonance imaging (MRI) is a powerful diagnostic tool for many diseases. In many situations, the contrasts are repeatedly administrated in order to monitor and assess the disease progression.

To investigate and compare the biological effects of γ-Fe₂O₃ nanoparticle (NP) and gadolinium dimeglumine (Gd-DTPA) with high and multiple doses on the kidney of healthy mice.

Polydextrose sorbitol carboxymethyl ether coated γ-Fe₂O₃ NP with hydrodynamic size of 68.2 nm and clinically applied Gd-DTPA were employed on healthy mice with the repeatedly intravenous administration of high doses. The cell viability of human umbilical vein endothelial cells (HUVEC) in high doses of these two contrast agents were measured using the xCELLigence Real-Time Cell Analysis (RTCA) S16 Instrument. The biological effects of γ-Fe₂O₃ NP and Gd-DTPA on the kidney were obtained using a biochemical automatic analyzer and multiple proinflammatory factor kit on the serum. Histopathological and immunohistochemistry analysis were taken on kidney tissues.

It showed that the proinflammatory responses elicited by the γ-Fe₂O₃ NPs were weaker than that by Gd-DTPA, evidenced by the relatively much lower level of IL-1β, IL-6, IL-18, TNF-α, C-reactive protein (CRP) and Ferritin. At the same time, the γ-Fe₂O₃ NPs did not have the biochemical index elevated, while the Gd-DTPA did.

The γ-Fe₂O₃ NPs induced weaker proinflammatory effects in reference to the Gd-DTPA, indicating better renal safety. Therefore, it is suggested that γ-Fe₂O₃ NPs should be safer and optional choice when repeated contrast-enhanced MRI is necessary.