Background: Combinatorial therapy based on anthracyclines and HER-2 blocking agents increases the risk of cardiomyopathy in women with breast cancer. Fructose is a monosaccharide associated with high risk of diabetes, non-alcoholic fatty liver disease, atherosclerosis and visceral obesity. A high fructose diet is a potential cardiometabolic risk factor and may increase cardiac risk in women with breast cancer treated with cardiotoxic drugs.
Purpose: In this study, we highlighted the role of sweeteners fructose in the worsening of cardiotoxicity induced by combinatorial therapy anthracycline-HER2-blocking agents
Methods: Human cardiomyocytes were pre-exposed with doxorubicin combined to trastuzumab (at 300 and 1000 nM) for 48 and 72h alone or combined to fructose at 0.25, 1 and 2.5 mM. After the incubation period, we performed the following tests: determination of cell viability, through mitochondrial dehydrogenase activity, study of lipid peroxidation (quantifying cellular Malondialdehyde and 4-hydroxynonenal), intracellular Ca2+ homeostasis. Moreover, pro-inflammatory studied were also performed (activation of NLRP3 inflammasome; expression of peroxisome proliferator-activated receptor-α; transcriptional activation of p65/NF-κB and secretion of cytokines involved in cardiotoxicity (Interleukins 1β, 8, 6, CXCL-12).
Results: High fructose increases significantly cell mortality of cardiomyocytes exposed to doxorubicin and trastuzumab thorugh the activation of NLRP-3 and Myd-88 expression. Intracellular Ca++ levels were also increased of 4 times compared to non-fructose exposed cardiomyocytes; MDA and 4-HNA levels were increased of 48,3 and 51,2 % compared to non-fructose exposed cells (0.001). Fructose increases IL-1, IL-6 and CXCL-12 expression in cardiomyocytes in a concentration dependent manner, compard to doxorubicin-trastuzumab group (0.05).
Conclusion: Data of the present study indicate that fructose induces a pro-inflammatory phenotype in human cardiac cells exposed to anticancer cardiotoxic drugs, providing even more data on the harmful role of fructose as a key player of cardiotoxic phenomena.