Aptamer delivery of siRNA, radiopharmaceutics and chemotherapy agents in cancer

Submitted by Repositório Arca ([email protected]) on 2019-03-07T16:42:52Z No. of bitstreams: 2 license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) F09-1-s2.0-S0378517317302740-main.pdf: 1028133 bytes, checksum: 737e8f1013224eadc51e5db7dd6ce9bb (MD5)Approved for entry into archive by monique santos ([email protected]) on 2019-03-08T19:35:17Z (GMT) No. of bitstreams: 2 F09-1-s2.0-S0378517317302740-main.pdf: 1028133 bytes, checksum: 737e8f1013224eadc51e5db7dd6ce9bb (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5)Made available in DSpace on 2019-03-08T19:35:17Z (GMT). No. of bitstreams: 2 F09-1-s2.0-S0378517317302740-main.pdf: 1028133 bytes, checksum: 737e8f1013224eadc51e5db7dd6ce9bb (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2017Instituto de Radioproteção e Dosimetria. Comissão Nacional de Energia Nuclear. Laboratório de Radiobiologia. Divisão de Física Médica. Rio de Janeiro, RJ, Brasil.Instituto de Radioproteção e Dosimetria. Comissão Nacional de Energia Nuclear. Laboratório de Radiobiologia. Divisão de Física Médica. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto de Tecnologia em Imunobiológicos. Rio de Janeiro, RJ, Brasil.Instituto de Radioproteção e Dosimetria. Comissão Nacional de Energia Nuclear. Laboratório de Radiobiologia. Divisão de Física Médica. Rio de Janeiro, RJ, Brasil / Universidade Federal do Rio de Janeiro. Instituto de Biofísica Carlos Chagas Filho. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto de Tecnologia em Imunobiológicos. Rio de Janeiro, RJ, Brasil.Aptamers are oligonucleotide reagents with high affinity and specificity, which among other therapeutic and diagnostic applications have the capability of acting as delivery agents. Thus, aptamers are capable of carrying small molecules, nanoparticles, radiopharmaceuticals or fluorescent agents as well as nucleic acid therapeutics specifically to their target cells. In most cases, the molecules may possess interesting therapeutic properties, but their lack of specificity for a particular cell type, or ability to internalise in such a cell, hinders their clinical development, or cause unwanted side effects. Thus, chemotherapy or radiotherapy agents, famous for their side effects, can be coupled to aptamers for specific delivery. Equally, siRNA have great therapeutic potential and specificity, but one of their shortcomings remain the delivery and internalisation into cells. Various methodologies have been proposed to date, including aptamers, to resolve this problem. Therapeutic or imaging reagents benefit from the adaptability and ease of chemical manipulation of aptamers, their high affinity for the specific marker of a cell type, and their internalisation ability via cell mediated endocytosis. In this review paper, we explore the potential of the aptamers as delivery agents and offer an update on current status and latest advancements

Caspase-3 activation and increased procollagen type I in irradiated hearts

The caspase-3-cleaved presence was evaluated in this study in the heart of irradiated rats, during the decline of ventricular function. Female Wistar rats were irradiated with a single dose of radiation (15 Gy) delivered directly to the heart and the molecular, histological and physiological evaluations were performed at thirteen months post-irradiation. The expressions of procollagen type I, TGF-ß1 and caspase-3-cleaved were analyzed using Western blotting. Cardiac structural and functional alterations were investigated by echocardiography and electron microscopy. In the irradiated group, the levels of procollagen type I, TGF-ß1 and caspase-3-cleaved are increased. Significant histological changes (degeneration of heart tissue and collagen deposition) and functional (reduced ejection fraction) were observed. Data suggest that the cardiac function decline after exposure to ionizing radiation is related, in part, to increased collagen and increased caspase-3-cleaved