The effects of triblock copolymer nano-vesicles loaded with propolis on heart failure model of rats

Abstract

Heart failure (HF) is one of the diseases that lead to high mortality of patients. Finding natural compounds with cardioprotective properties and identifying their action mechanisms is of great importance. In this research, the effect of propolis and triblock copolymer nano-vesicles loaded with propolis were studied in Wistar rats HF model. After preparing propolis and Polylactide-block-poly (ethylene glycol)-block-polylactide (PLA-PEG-PLA) loaded with propolis using thin film hydration method, nanoparticles were identified using transmission electron microcopy (TEM) and Zetasizer techniques. Induction of HF in animals was done with 85 mg/kg isoproterenol for 2 consecutive days and 200 mg/kg/day of both propolis and PLA-PEG-PLA nano-vesicle loaded with propolis were administered to rats by oral gavage one week before HF induction and one week after that. On the last day, echocardiography parameters were measured and then, with blood sampling and plasma preparation, the levels of biochemical parameters such as B-type natriuretic peptide (BNP), Galectin-3, interleukin 1β (IL-1β), interleukin 6 (IL-6), interleukin 10 (IL-10), interleukin (IL-17), reduced AMP-activated protein kinase (AMPK) and silent information regulator (SIRT1) were measured using Enzyme-linked immunosorbent assay (ELISA) technique. Both propolis and PLA-PEG-PLA nano-vesicle loaded with propolis led to improvement of echocardiographic parameters in HF rats. Also, the administration of these two compounds decreased the expression of inflammatory cytokines IL-1, IL-6 and IL-17 and increased the expression of IL-10 in HF rats. The levels of SIRT1 and AMPK in HF rats receiving propolis and PEG-PLA loaded with propolis were upregulated compared to HF control ones. In conclusion, it can be indicated that propolis and PEG-PLA loaded with propolis have cardio protection effects through decreasing inflammation and activation of SIRT1-AMPK axis.