Selenium in Action: Exploring the Biological Wonders of Hydroselenite Salts

Despite the wealth of data related to the advantages of formulating a wide range of compounds as salts to ameliorate their biological properties, there is scant information regarding the therapeutic potential of selenium (Se) salts. In this work, we have formulated six antibiotics as hydroselenite salts in order to compare their in vitro antibacterial and anticancer effects and evaluate if this approach could enhance their water solubility. In this regard, in almost all the cases, their solubility was increased by one order of magnitude. All the compounds were screened against a panel of three Gram-positive and three Gram-negative bacteria. Likewise, their antiproliferative activity was evaluated in breast, prostate, glioblastoma, and pancreatic cancer cell lines. Normal human dermal fibroblasts (NHDF) were used to determine their selectivity indexes (SI). Additionally, these novel hydroselenite salts were submitted to the National Cancer Institute (NCI) to study their antitumoral potential. Compounds SLT-2 and SLT-6 showed potent cytotoxicity against the glioblastoma cancer cell line, and their ability to induce apoptosis and reactive oxygen species (ROS) was further assessed. To conclude, we have demonstrated that the formulation of several antibiotics as hydroselenite salts could be a feasible approach to obtain biologically active compounds with an enhanced effect.