• SGLT2i
• zebrafish
• type 2 diabetes mellitus

Diabetes mellitus is a chronic metabolic disease, caused by an absolute or relative defect of insulin, the pancreatic hormone through which cells pick up and use glucose for energetic production. Type 2 diabetes mellitus (T2DM) is the most common form of diabetes, characterized by hyperglycaemia due to poor secretion of insulin and/or insulin inability in acting on target cells. Cardiovascular disease is the first cause of death among diabetic patients, who have double probability of cardiovascular disease onset compared with non diabetic people [Avogaro A., 2015]. Recently, a new class of antidiabetic drugs, the inhibitors of SGLT2 (SGLT2i), have attracted attention thanks to their action on both glycemic control and cardiovascular risks (body weight, visceral adiposity, blood pressure, lipidic profile and quantity of uric acid). Canagliflozin, Empagliflozin and Dapagliflozin are the drugs, belonging to this class, now approved in Europe and U.S.A.
Despite numerous clinical trials have demonstrated the positive impact of this class of drugs on cardiovascular complications, the specific mechanisms by which SGLT2i act have only been partially clarified. A deeper knowledge of these mechanisms is necessary for a better discrimination of the SGLT2i drugs' specific effects and, therefore, for a more specific use of the drugs in different pathological contexts.
This project wants to verify the possibility in using Zebrafish as a model organism for the in vivo investigation of the SGLT2 inhibitors' ways of action on cardiovascular front. The aim of this thesis is to induce a cardiac damage in the model organism in order to value if SGLT2i are able to produce a protective effect also in Zebrafish. The simulation of cardiac injury was obtained using two different cardio-toxic substances: doxorubicin (Doxo) and aristolochic acid (AA). After testing the substances' right dose toxicity, experiments were realized on three different embryos' groups: the control group (treated with DMSO, the drug solvent), the group exposed to AA/Doxo and the group treated with AA/Doxo and the specific SGLT2i. Through in vivo imaging, the drug's action on cardiac morphology and on the rate of contraction compromised by the cardiotoxic substance was analysed. A direct observationof zebrafish heart was made possible by embryonic transparency and by the use of transgenic line Myl7-EGFP, which has a fluorescent heart. At the molecular level, the evaluation of cardiac hypertrophy marker gene modulation was carried out using Real-time PCR, as the cardiac hypertrophy is frequently present in T2DM patients. Even in adult organisms, the drugs cardiac effect was tested on a cardio-toxic model, obtained by an intraperitoneal injection of Doxo. Four weeks after injection heart were dissected and morphologically and molecularly analyzed.
The preliminary data, obtained on the embryonic models, suggest the ability of drugs in acting positively on cardiac alterations also in Zebrafish.