These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: 68Ga-labelled-exendin-4: New GLP1R targeting agents for imaging pancreatic β-cell and insulinoma.
    Author: Li L, Zhao R, Hong H, Li G, Zhang Y, Luo Y, Zha Z, Zhu J, Qiao J, Zhu L, Kung HF.
    Journal: Nucl Med Biol; 2021; 102-103():87-96. PubMed ID: 34695640.
    Abstract:
    OBJECTIVE: Glucagon-like peptide-1 receptor (GLP1R) specifically expressed on the surface of pancreatic β-cells and insulinoma, is a potential biomarker for imaging β-cell mass (BCM). In this study, two new 68Ga-labelled GLP1R targeting agents were prepared and their biological properties for imaging BCM and insulinoma were evaluated. METHODS: [68Ga]Ga-HBED-CC-MAL-Cys39-exendin-4 ([68Ga]Ga-4) and its dimer ([68Ga]Ga-5) were synthesized from corresponding precursors. Cell uptake studies were evaluated in INS-1 cells. Biodistribution and microPET studies were performed in male normal Sprague-Dawley rats, diabetic rats and insulinoma xenograft NOD/SCID mice. RESULTS: [68Ga]Ga-4 and [68Ga]Ga-5 were efficiently radiolabelled by a simple one-step reaction without purification leading to high radiochemical yields and radiochemical purities (both >95%, decay corrected, n = 6, molar activity 15 GBq/μmol). They both showed excellent stability (~95%) in phosphate-buffered saline, pH 7.4, and in rat serum (~90%) for 2 h. Biodistribution studies and small animal PET/CT imaging showed that [68Ga]Ga-4 displayed specific uptake in rat pancreas and mouse insulinoma, and a reduced uptake in the pancreas of diabetic rat was observed (~62% reduction). Notably, it exhibited a rapid time-to-peak pancreatic uptake (0.96 ± 0.19%ID/g in 15 min) and fast clearance from the kidney (42% clearance in 30 min). Results suggested a favorable in vivo kinetics for human imaging studies. CONCLUSIONS: [68Ga]Ga-4 targeting GLP1R of pancreatic β-cells may be a potentially useful PET agent and a suitable candidate for further structural modification studies. This agent has demonstrated several advantages, rapid time-to-peak pancreatic uptake and faster clearance from the kidney, factors may enhance diagnosis of diabetes and insulinoma.
    [Abstract] [Full Text] [Related] [New Search]