Natriuretic peptides expression in a murine model of myocardial infarction after Sangiovese grape juice intake. Focus on CNP and ON putative involvement of plant miRNAs in-vitro and in healthy humans

Background-aim A regular intake of red grape juice has cardioprotective properties, but its role on the modulation of natriuretic peptides (NPs), in particular of C-type NP (CNP), has not yet been proven. The aims were to evaluate: 1) in vivo the effects of long-term intake of Tuscany Sangiovese grape juice (SGJ) on the NPs system in a mouse model of MI; 2) in vitro the response to SGJ small RNAs of murine MCEC-1 under physiological and ischemic condition; 3) the activation of the CNP/NPR-B/NPR-C in healthy human subjects after 7 days' SGJ regular intake. Methods 1) C57BL/6J mice (n = 33) were randomly subdivided into: Sham (n = 7), MI (n = 15) and MI fed for 4 weeks with a normal chow supplemented with Tuscany SGJ (25% vol/vol, 200 μl/die) (MI + SGJ, n = 11). Echocardiography and histological analyses were performed. Myocardial NPs transcriptional profile was investigated by Real-Time PCR. 2) MCEC-1 were treated for 24 h with a pool of SGJ small RNAs and cell viability under 24 h exposure to H2O2 was evaluated by MTT assay. 3) Human blood samples were collected from 7 subjects before and after the 7 days' intake of Tuscany SGJ. Real-time PCR reactions were performed. Total RNA and miRNAs were extracted with dedicated assays. Real-time PCR reactions were performed. Results 1) the regular intake of SGJ significantly attenuated the infarct scar size by 32% and the post-MI increase in ANP mRNA cardiac levels, but not the post-MI increase in BNP mRNA cardiac levels. Interestingly, CNP mRNA cardiac levels were significantly increased in MI + SGJ mice compared to sham (p = .007) and MI (p = .03) groups. In MI + SGJ hearts, the mRNA expression of NP receptors (NPR) –B and –C was significantly lower than MI, whereas NPR-A gene expression was higher than MI hearts; 2) The treatment of MCEC-1 cells with Sangiovese small RNAs increased tolerance to H2O2-induced cell death (p < .0001). Moreover, the profile of grapevine miRNAs was characterized; 3) In human blood samples the activation of CNP/NPR-B/NPR-C pathway was activated after SGJ supplementation and circulating levels of plant miRNAs were significantly increased. Conclusions The regular intake of SGJ exerts anti-remodeling effects in a murine model of MI by inducing CNP/NPR-B/NPR-C pathway. In vitro, SGJ-derived miRNAs improve endothelial cell viability under stress. Finally, the CNP/NPR-B/NPR-C pathway activation is detectable in human subjects with higher circulating levels of grapevine miRNAs after SGJ intake. Our data may support the development of a novel nutraceutical approach for cardioprotection.