Background: Anthracyclines are essential adjuvant therapies for a variety of cancers, particularly breast, and gastric and esophageal cancers. Whilst prolonging cancer-related survival, these agents can in-duce drug-related cardiotoxicity. Spirulina, Reishi (Ganoderma Lucidum) and Moringa are three nutaceuticals with anti-inflammatory effects that are currently used in cancer patients to improve quality of life and fatigue.
Methods: Female C57Bl/6 mice were untreated (Sham, n=6) or treated for 10 days with short-term doxorubicin i.p at 2.17 mg/kg (DOXO, n=6), Singo at 12 mg/kg (Singo, n=6) or doxorubicin combined to Singo (DOXO-Singo, n=6). Ejection fraction, radial and longitudinal strain were analyzed through transthoracic echocardiography (Vevo 2100, Fujifilm). Myocardial expression of NLRP3, DAMPs (galectine 3 and calgranulin S100) and 13 cytokines (IL-1α, IL-1β, IL-2, IL-4, IL-6, IL-10, IL-12, IL17-α, IL-18, IFN-γ, TNF-α, G-CSF, and GM-CSF) were quantified through selective mouse ELISA methods. Myocadial fibrosis, necrosis and hypertrophy were analyzed through Immunohistochemistry (IHC). Human cardiomyocytes (HFC cell line) were exposed to subclinical concentration of doxorubicin (200 nM) alone or in combination to Singo ( at 10, 25 and 50 µg/ml) for 24 and 48h. Cell viability studies were performed through MTS assay. Expression of NLRP3 and p65/NF-kB) were made through selective ELISA methods. .
Results: In preclinical models of short-term DOXO cardiotoxicity, Singo improved significantly EF and FS and prevented the reduction of radial and longitudinal strain after 10 days of treatment with DOXO. A reduced expression of myocardial NLRP3 and NF-kB levels in cardiac tissues were seen in DOXO-Singo group compared to DOXO mice (p<0.05). Myocardial expression of pro-inflammatory cytokines were significantly reduced after treatment with Singo indicating anti-inflammatory properties. Myocardial levels of Cal-granulin S100 and galectine-3 were strongly enhanced in DOXO group; on the other hand their expression were reduced in Singo-DOXO group vs DOXO (p<0.05). Immunohistochemistry analysis indicates that Singo reduces fibrosis and hypertrophy in myocardial tissue of mice during exposure to DOXO.
Conclusion: Singo is able to improve cardiac function and reduce biomarkers involved in heart failure and fibrosis. Cardioprotective properties of Singo are mediated by the reduction of lipid peroxidation products and expression of NLRP3-NF-kB –cytokine pathways.