Influence of Spondias mombin L. supplementation on cardiac remodeling after acute myocardial infarction

Author(s)

Bruna Letícia Buzati Pereira

• Document type: Doctoral Thesis
• Press: Botucatu. 2019-02-25.
• Institution: Universidade Estadual Paulista (Unesp). Faculdade de Medicina. Botucatu
• Defense date: 2019-02-14
• Advisor: Marcos Ferreira Minicucci

Abstract

Myocardial infarction (MI) is one of the leading causes of morbidity and mortality worldwide. Therefore, dietary intervention on cardiac remodeling after MI has significant clinical relevance. Spondias mombin L. (SM) is a natural fruit with antioxidant and anti-inflammatory properties, but its effect on the structure and ventricular function after MI is unknown. In order to determine the effect of SM consumption on cardiac remodeling after MI, male Wistar rats were assigned to four groups: the sham group (animals that underwent simulated surgery) that received a standard chow (S; n=20); the infarcted group that received a standard chow (MI; n=24); the infarcted group supplemented with 100mg of SM/kg body weight/day) (MIS100; n=23) and the infarcted group supplemented with 250mg of SM/kg body weight/day) (MIS250; n=22). After 3 months of treatment, echocardiographic study, isolated heart study and euthanasia were performed. Left ventricular samples were evaluated for fibrosis, hypertrophy, oxidative stress, DNA damage and inflammatory activity. For statistical analysis, the 1-way ANOVA test was performed with Holm-Sidak post-test and the values obtained were presented as mean ± standard deviation or the Kruskal-Wallis test with Dunn post-test and the values obtained were presented as median and interquartile range. MI induced structural and functional changes in the left ventricle with worsening of systolic and diastolic function, and SM supplementation in different doses did not influence these variables analyzed by echocardiography and by the study of the isolated heart (p> 0.05). There was no statistically significant difference between groups in DNA damage analysis evaluated by the comet assay (p> 0.05). SM supplementation attenuated cardiac remodeling after MI reducing fibrosis (p= 0.047) and hypertrophy (p= 0.006), in which case the reduction in the group supplemented with the highest SM dose was more efficient. SM supplementation improved oxidative stress by lower formation of lipid hydroperoxide (p= 0.032) and greater antioxidant activity of the catalase (p= 0.017) and glutathione peroxidase (p <0.001), and for this, the supplementation in the highest dose was more efficient. SM supplementation in the highest dose also increased the activity of the superoxide dismutase enzyme (p= 0.003). SM supplementations improved the inflammatory process attenuating the activation of the inflammatory pathway by lower expression of the IkB-β (inhibitor protein kB) (p= 0.034), lower phosphorylation of the nuclear factor kappa B (NFkB), demonstrated by the relation between total NFkB/ phosphorylated NFkB (p = 0.029), by reducing the expression of tumor necrosis factor alpha (TNF-α) (p = 0.001) and interferon gamma (IFN-γ) (p = 0.006). The infarcted group supplemented with higher SM dose also presented higher expression of the anti-inflammatory cytokine Il-10, similar to infarcted group that received control ration (p= 0.004). We conclude that SM supplementation attenuates cardiac remodeling after MI and that SM supplementation in the higher dose seems to be more effective. (AU)

• FAPESP's process: 14/23215-5 - Influence of Spondias mombin supplementation on the cardiac remodeling after acute myocardial infarction
• Grantee: Bruna Letícia Buzati Pereira
• Support Opportunities: Scholarships in Brazil - Doctorate