Cytotoxic and genotoxic effects induced by stannous chloride associated to nuclear medicine kits

• Published in: Nuclear medicine and biology Vol. 33; no. 7; pp. 915 - 921
• Main Authors: Guedes, Anderson P., Cardoso, Valbert N., De Mattos, Jose C.P., Dantas, Flavio J.S., Matos, Vanessa C., Silva, Josiane C.F., Bezerra, Roberto J.A.C., Caldeira-de-Araujo, Adriano
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-10-2006
• Subjects: Cell Survival - drug effects; Cytotoxicity potentiality; DNA, Bacterial - drug effects; Dose-Response Relationship, Drug; Escherichia coli; Escherichia coli - cytology; Escherichia coli - drug effects; Escherichia coli - genetics; Genotoxicity potentiality; Mutagenicity Tests; Mutation; Nuclear Medicine - instrumentation; Plasmid pUC 9.1; Radiopharmaceutical kits; Reagent Kits, Diagnostic; Stannous chloride; Tin Compounds - administration & dosage; Stannous chloride; Genotoxicity potentiality; Escherichia coli; Cytotoxicity potentiality; Plasmid pUC 9.1; Radiopharmaceutical kits
• ISSN: 0969-8051; 1872-9614
• DOI: 10.1016/j.nucmedbio.2006.07.008

At present, more than 75% of routine nuclear medicine diagnostic procedures use technetium-99m (
99mTc). The binding between
99mTc and the drug to obtain the radiopharmaceutical needs a reducing agent, with stannous chloride (SnCl
2) being one of the most used. There are controversies about the cytotoxic, genotoxic and mutagenic effects of SnCl
2 in the literature. Thus, the approaches below were used to better understand the biological effects of this salt and its association in nuclear medicine kits [methylenediphosphonate (MDP) bone scintigraphy and diethylenetriaminepentaacetic acid (DTPA) kidney and brain scintigraphy]: (i) bacterial inactivation experiments; (ii) agarose gel electrophoresis of supercoiled and linear plasmid DNA and (iii) bacterial transformation assay. The
Escherichia coli strains used here were AB1157 (wild type) and BW9091 (
xthA mutant). Data obtained showed that both MDP and SnCl
2 presented a high toxicity, but this was not observed when they were assayed together in the kit, thereby displaying a mutual protect effect. DTPA salt showed a moderate toxicity, and once more, the DTPA kit provided protection, compared to the SnCl
2 effect alone. The results suggest a possible complex formation, either MDP-SnCl
2 or DTPA-SnCl
2, originating an atoxic compound. On the other hand, SnCl
2-induced cell inactivation and the decrease in bacterial transformation generated by DTPA found in XthA mutant strain suggest that the lack of this enzyme could be responsible for the effects observed, being necessary to induce DNA damage repair.