Mn(II) Complex of Lipophilic Group-Modified Ethylenediaminetetraacetic Acid (EDTA) as a New Hepatobiliary MRI Contrast Agent

Liver-specific contrast agents (CAs)
can improve the Magnetic resonance
imaging (MRI) detection of focal and diffuse liver lesions by increasing
the lesion-to-liver contrast. A novel Mn­(II) complex, Mn-BnO-TyrEDTA,
with a lipophilic group-modified ethylenediaminetetraacetic acid (EDTA)
structure as a ligand to regulate its behavior in vivo, is superior
to Gd-EOB-DTPA in terms of a liver-specific MRI contrast agent. An
MRI study on mice demonstrated that Mn-BnO-TyrEDTA can be rapidly
taken up by hepatocytes with a combination of hepatobiliary and renal
clearance pathways. Bromosulfophthalein (BSP) inhibition imaging,
biodistribution, and cellular uptake studies confirmed that the mechanism
of hepatic targeting of Mn-BnO-TyrEDTA is the hepatic uptake of the
amphiphilic anion contrast agent mediated by organic anion transporting
polypeptides (OATPs) expressed by functional hepatocytes.