Necrosis affinity evaluation of 131I-hypericin in a rat model of induced necrosis. (July 2013)

• Record Type: Journal Article
• Authors: Kong, Ming; Zhang, Jian; Jiang, Cuihua; Jiang, Xiao; Li, Yue; Gao, Meng; Yao, Nan; Huang, Dejian; Wang, Xiaoning; Fang, Zhijun; Liu, Wei; Sun, Ziping; Ni, Yicheng
• Is Part Of: Journal of drug targeting. Volume 21:Number 6(2013)
• Page Start: 604
• Page End: 610
• Publication Date: 2013-07
• Subjects: Drug delivery systems -- Periodicals; Drug Delivery Systems; Vehicles; Drug Administration Routes; Drug Evaluation; 615.7
• DOI: 10.3109/1061186X.2013.789034
• Languages: English
• ISSNs: 1061-186X

Abstract

<abstract> <title>Abstract</title> <p>Cancers are often with spontaneous or therapeutic necrosis that could be utilized as a generic target for developing new treatments. The purpose of this study was to investigate the biodistribution and pharmacokinetics of radioiodinated hypericin (Hyp), a naturally occurring compound, after intravenous (i.v.) injection in a rat model of liver and muscle necrosis (<italic>n</italic> = 42), and evaluate its necrosis affinity. Hyp was labeled with <sup>131</sup>I with labeling efficiency >99%. After incubating in solution/rat plasma for 8 days, radiochemical purity of <sup>131</sup>I-Hyp remained 98.1 and 97.1%, respectively, indicating good <italic>in vitro</italic> stability. SPECT-CT images at 24 h after i.v. injection of <sup>131</sup>I-Hyp in rats with induced liver and muscle necrosis showed obvious tracer absorption in necrotic tissues. Biodistribution studies revealed that the percentage of the injected dose per gram of tissue (%ID/g) evolved from 1.9 %ID/g at 6 h, through a maximum 3.0 %ID/g at 12 h, to 1.0 %ID/g at 192 h in necrotic liver. Pharmacokinetics studies revealed that the terminal elimination half-life, total body clearance and area under the curve of <sup>131</sup>I-Hyp were 32.7 h, 9.2 L/h/kg and 1.6 MBq/L*h, respectively. These results demonstrated that <sup>131</sup>I-Hyp features a long blood circulation in animals and persistent retention in necrotic tissues. Therefore, <sup>131</sup>I-labeled Hyp could be a broad-spectrum anti-tumor agent with a cost much cheaper relative to the biological agents such as monoclonal antibodies.</p> </abstract>