Distribution of technetium-99m PEG-liposomes during oligofructose-induced laminitis development in horses

• Published in: The veterinary journal (1997) 2015-11, Vol.206 (2), p.218-225
• Main Authors: Underwood, Claire, Pollitt, Christopher C., Metselaar, Josbert M., Laverman, Peter, van Bloois, Louis, van den Hoven, Jolanda M., Storm, Gert, van Eps, Andrew W.
• Format: Article
• Language: English
• Subjects: Animals; Foot Diseases - diagnostic imaging; Foot Diseases - metabolism; Foot Diseases - veterinary; Hoof and Claw - pathology; Horse; Horse Diseases - chemically induced; Horse Diseases - diagnostic imaging; Horses; Inflammation - chemically induced; Inflammation - diagnostic imaging; Inflammation - veterinary; Liposome; Liposomes - chemistry; Male; Nanoparticle; Nanotechnology; Oligosaccharides - toxicity; Polyethylene Glycols - chemistry; Radiopharmaceuticals - pharmacokinetics; Scintigraphy; Technetium Tc 99m Exametazime - pharmacokinetics
• ISSN: 1090-0233; 1532-2971
• DOI: 10.1016/j.tvjl.2015.07.013

•This study investigated whether polyethylene-glycol liposomes accumulate in the lamellar tissue during laminitis development.•99mTc-PEG-liposomes were administered to normal horses and horses with oligofructose-induced laminitis.•Scintigraphy and lamellar tissue collection demonstrated liposome accumulation in the lamellar tissue of horses with laminitis.•Liposomes may have potential for targeted lamellar drug delivery in acute laminitis. Liposomes are phospholipid nanoparticles used for targeted drug delivery. This study aimed to determine whether intravenous liposomes accumulate in lamellar tissue during laminitis development in horses so as to assess their potential for targeted lamellar drug delivery. Polyethylene-glycol (PEG) coated liposomes were prepared according to the film hydration method and labelled using 99mTc-hexamethyl-propylene-amine-oxime. Six horses received 10 g/kg oligofructose via nasogastric tube to induce laminitis, and four control horses received water via nasogastric tube. All horses received 300 µmol 99mTc-PEG-liposomes (5.5 GBq) plus 5.5 µmol/kg PEG-liposomes by slow intravenous infusion. Scintigraphic imaging was performed at 0, 6 and 12 h post-infusion. Technetium-99m liposome uptake was measured in regions of interest over the hoof, fetlock and metacarpus. At the study end-point horses were euthanased, tissue samples collected and tissue liposome levels were calculated as the percentage of the injected dose of 99mTc-liposomes per kilogram of tissue. Data were analysed non-parametrically. All horses receiving oligofructose developed clinical and histological signs of laminitis. Technetium-99m liposome uptake in the hoof increased with time in laminitis horses (P = 0.04), but decreased with time in control horses (P = 0.01). Technetium-99m liposome levels in lamellar tissue from laminitis horses were 3.2-fold higher than controls (P = 0.02) and were also higher in laminitis vs. control skin, muscle, jejunum, colon, and kidney (P