Use of ¹¹¹In-Hexavalent Lactoside for Liver Reserve Estimation in Rodents with Thioacetamide-Induced Hepatic Fibrosis

Abstract

Many biochemical tests detecting the presence of liver disease are not liver-specific and may be abnormal in nonhepatic conditions. The asialoglycoprotein receptor (ASGPR) is a hepatocyte-specific receptor for Gal/GalNAc-terminated glycopeptide or glycoprotein. The number of these receptors decreases in patients with chronic liver diseases. Here, we aimed to evaluate the use of 111 In-hexavalent lactoside, a known ASGPR imaging biomarker, as a more sensitive probe to detect small changes in liver reserve in animal models of chronic liver injury. Thioacetamide (TAA) treatment via intraperitoneal injection every 2 days in BALB/c mice continued for 1, 2, 3, or 4 months. The liver fibrosis stages were determined by Sirius Red staining and were based on the METAVIR classification method. Serum transaminase enzymes (alanine transaminase (ALT) and aspartate transaminase (AST)), alkaline phosphatase, albumin, and bilirubin were measured using a FUJI FDC3500 i/s analyzer. The ASGPR staining was performed by immunohistocytochemical stain. The percentages of fibrosis and ASGPR were calculated using ImageJ software after collagen staining and anti-ASGPR staining, respectively. A nanoSPECT/CT was used for molecular imaging and liver uptake measurement. We observed fibrosis grades of F0−F1 in mice treated with TAA for 1 month, F2 in mice treated for 2 months, F3−F4 in mice treated for 3 months, and F4 in mice treated for 4 months. The levels of ALT and albumin were not significantly different in the TAA groups from those in the controls. Although the average levels of AST, alkaline phosphatase, and bilirubin in the TAA groups were different from those in the control group, there was little difference between TAA groups. More sensitive distinctions among TAA groups were detected in 111 In-hexavalent lactoside uptake of ASGPR, ASGPR staining, and fibrosis % than when using the conventional AST, ALT, albumin, alkaline phosphatase, and bilirubin tests. The absorption and distribution of 111 In-hexavalent lactoside were lower in the chronic hepatitis models than the normal controls. The liver reserves measured by 111 In-hexavalent lactoside uptake were 71.7 ± 7.5% and 50.9 ± 5.6% after 1 and 2 months, respectively, of TAA treatment. As an ASGPR biomarker, 111 In-hexavalent lactoside has higher sensitivity than traditional liver function tests and collagen stain to provide more objective data for evaluating compensated cirrhosis or changes in liver damage. ASGPR staining can reflect the regenerated hepatocytes, but the need for a biopsy limits its use. 111 Inhexavalent lactoside measurement is comparable with ASGPR staining, which suggests that 111 In-hexavalent lactoside measurement will be more useful as a practical, noninvasive test of chronic liver injury.

Advances on Nanomedicines for Diagnosis and Theranostics of Hepatic Fibrosis

“…For example, the number of the asialoglycoprotein receptor (ASGPR), highly expressed in healthy hepatocytes to remove galactose (Gal)‐ or N ‐acetylgalactosamine (GalNAc)‐terminated glycoproteins during their circulation to remain normal metabolism, [ 86 ] would be significantly decreased in the course of hepatic fibrosis. [ 87 ] In this context, several nuclear medicine contrast agents, such as a fluorine‐18‐labeled galactose derivative [ 18 F]FPGal, [ 88 ] 99m Tc‐p(VLA‐co‐VNI), [ 89 ] 18 F‐FBHGal, [ 90 ] and 111 In‐hexavalent lactoside, [ 91 ] have been introduced as effective imaging probes for the detection of hepatic fibrosis lesions and staging of the disease course. But radiotoxicity of these contrast agents and a high cost of nuclear medicine examinations have significantly hampered their wide application clinically.…”

Metal-Based Complexes as Pharmaceuticals for Molecular Imaging of the Liver

“…Conjugates of NGA labeled with 111 In have shown hepatic accumulation in mice [174]. Hexavalent lactoside modified with DTPA to chelate 111 In also exhibited nearly exclusive accumulation in rat and mice liver [175,176,177]. 111 In complexes of DTPA derivatives bearing aromatic moieties also exhibit mainly hepatobiliary excretion, comparably to their Gd(III) analogs [178,179].…”