Differences in the Renal Accumulation of Radiogallium-Labeled (Glu)<sub>14</sub> Peptides Containing Different Optical Isomers of Glutamic Acid
Kazuma Ogawa,
Kota Nishizawa,
Kenji Mishiro,
Masayuki Munekane,
Takeshi Fuchigami,
Hiroaki Echigo,
Hiroshi Wakabayashi,
Seigo Kinuya
Affiliations
Kazuma Ogawa
Institute for Frontier Science Initiative, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Ishikawa, Japan
Kota Nishizawa
Graduate School of Medical Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Ishikawa, Japan
Kenji Mishiro
Institute for Frontier Science Initiative, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Ishikawa, Japan
Masayuki Munekane
Graduate School of Medical Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Ishikawa, Japan
Takeshi Fuchigami
Graduate School of Medical Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Ishikawa, Japan
Hiroaki Echigo
Graduate School of Medical Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Ishikawa, Japan
Hiroshi Wakabayashi
Department of Nuclear Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Takara-machi 13-1, Kanazawa 920-8641, Ishikawa, Japan
Seigo Kinuya
Department of Nuclear Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Takara-machi 13-1, Kanazawa 920-8641, Ishikawa, Japan
Acidic amino acid peptides have a high affinity for bone. Previously, we demonstrated that radiogallium complex-conjugated oligo-acidic amino acids possess promising properties as bone-seeking radiopharmaceuticals. Here, to elucidate the effect of stereoisomers of Glu in Glu-containing peptides [(Glu)14] on their accumulation in the kidney, the biodistributions of [67Ga]Ga-N,N′-bis-[2-hydroxy-5-(carboxyethyl)benzyl]ethylenediamine-N,N′-diacetic acid-conjugated (l-Glu)14 ([67Ga]Ga-HBED-CC-(l-Glu)14), [67Ga]Ga-HBED-CC-(d-Glu)14, [67Ga]Ga-HBED-CC-(dl-Glu)14, and [67Ga]Ga-HBED-CC-(d-Glu-l-Glu)7 were compared. Although the accumulation of these compounds in the bone was comparable, their kidney accumulation and retention were strikingly different, with [67Ga]Ga-HBED-CC-(d-Glu-l-Glu)7 exhibiting the lowest level of kidney accumulation among these compounds. Repeated d- and l-peptides may be a useful method for reducing renal accumulation in some cases.
