<sup>123</sup>I-BMIPP, a Radiopharmaceutical for Myocardial Fatty Acid Metabolism Scintigraphy, Could Be Utilized in Bacterial Infection Imaging
Yuka Muranaka,
Asuka Mizutani,
Masato Kobayashi,
Koya Nakamoto,
Miki Matsue,
Fumika Takagi,
Kenichi Okazaki,
Kodai Nishi,
Kana Yamazaki,
Ryuichi Nishii,
Naoto Shikano,
Shigefumi Okamoto,
Hideki Maki,
Keiichi Kawai
Affiliations
Yuka Muranaka
Division of Health Sciences, Graduate School of Medical Sciences, Kanazawa University, 5-11-80 Kodatsuno, Kanazawa 920-0942, Japan
Asuka Mizutani
Faculty of Health Sciences, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, 5-11-80 Kodatsuno, Kanazawa 920-0942, Japan
Masato Kobayashi
Faculty of Health Sciences, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, 5-11-80 Kodatsuno, Kanazawa 920-0942, Japan
Koya Nakamoto
Division of Health Sciences, Graduate School of Medical Sciences, Kanazawa University, 5-11-80 Kodatsuno, Kanazawa 920-0942, Japan
Miki Matsue
Ishikawa Prefectural Institute of Public Health and Environmental Science, 1-11, Taiyogaoka, Kanazawa 920-1154, Japan
Fumika Takagi
Laboratory for Drug Discovery & Disease Research, Shionogi & Co., Ltd., 3-1-1, Futaba-cho, Toyonaka 561-0825, Japan
Kenichi Okazaki
Laboratory for Drug Discovery & Disease Research, Shionogi & Co., Ltd., 3-1-1, Futaba-cho, Toyonaka 561-0825, Japan
Kodai Nishi
Department of Radioisotope Medicine, Atomic Bomb Disease Institute, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan
Kana Yamazaki
Department of Molecular Imaging and Theranostics, Institute for Quantum Medical Science, Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology, 4-9-1 Anagawa, Inage, Chiba 263-8555, Japan
Ryuichi Nishii
Department of Molecular Imaging and Theranostics, Institute for Quantum Medical Science, Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology, 4-9-1 Anagawa, Inage, Chiba 263-8555, Japan
Naoto Shikano
Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2 Ami, Inashiki 300-0394, Japan
Shigefumi Okamoto
Faculty of Health Sciences, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, 5-11-80 Kodatsuno, Kanazawa 920-0942, Japan
Hideki Maki
Laboratory for Drug Discovery & Disease Research, Shionogi & Co., Ltd., 3-1-1, Futaba-cho, Toyonaka 561-0825, Japan
Keiichi Kawai
Division of Health Sciences, Graduate School of Medical Sciences, Kanazawa University, 5-11-80 Kodatsuno, Kanazawa 920-0942, Japan
In this study, we evaluated the use of 15-(4-123I-iodophenyl)-3(R,S)-methylpentadecanoic acid (123I-BMIPP) to visualize fatty acid metabolism in bacteria for bacterial infection imaging. We found that 123I-BMIPP, which is used for fatty acid metabolism scintigraphy in Japan, accumulated markedly in Escherichia coli EC-14 similar to 18F-FDG, which has previously been studied for bacterial imaging. To elucidate the underlying mechanism, we evaluated changes in 123I-BMIPP accumulation under low-temperature conditions and in the presence of a CD36 inhibitor. The uptake of 123I-BMIPP by EC-14 was mediated via the CD36-like fatty-acid-transporting membrane protein and accumulated by fatty acid metabolism. In model mice infected with EC-14, the biological distribution and whole-body imaging were assessed using 123I-BMIPP and 18F-FDG. The 123I-BMIPP biodistribution study showed that, 8 h after infection, the ratio of 123I-BMIPP accumulated in infected muscle to that in control muscle was 1.31 at 60 min after 123I-BMIPP injection. In whole-body imaging 1.5 h after 123I-BMIPP administration and 9.5 h after infection, infected muscle exhibited a 1.33-times higher contrast than non-infected muscle. Thus, 123I-BMIPP shows potential for visualizing fatty acid metabolism of bacteria for imaging bacterial infections.
