Adherence to a Mediterranean dietary pattern was associated with higher circulating levels of mitochondrial microproteins and lower oxidative stress markers in older patients with atrial fibrillation, according to a cross-sectional pilot study published in Frontiers in Nutrition.
The study included 49 patients (mean age, 78 years) with nonvalvular atrial fibrillation. Adherence to the Mediterranean diet was assessed using a validated nine-item questionnaire, with patients categorized as having low-to-medium adherence (0–6 points) or high adherence (7–9 points).
Fasting plasma samples were used to measure levels of the mitochondrial microproteins Humanin and SHMOOSE (Small Human Mitochondrial Open Reading Frame Over Serine Transfer RNA), as well as oxidative stress markers soluble Nox2-derived peptide (sNox2-dp) and 8-iso-prostaglandin F2alpha.
Patients with high adherence to the Mediterranean diet had higher log-transformed circulating levels of both SHMOOSE and Humanin compared with those with low-to-medium adherence.
Analysis of individual dietary components showed that higher SHMOOSE levels were associated with consumption of at least one tablespoon of olive oil per day and less than one daily serving of white bread. Higher Humanin levels were observed in patients consuming at least one tablespoon of olive oil per day, three or more servings of fish per week, and two or more servings of legumes per week.
Humanin levels were inversely associated with both oxidative stress markers. However, after adjusting for sex and body mass index, only the association with sNox2-dp remained statistically significant. No statistically significant associations were observed between SHMOOSE levels and oxidative stress markers.
The study had several limitations. The cross-sectional design precludes causal inference, and the small sample size—limited to older patients with atrial fibrillation—may affect generalizability. Diet was assessed using a brief questionnaire that may not fully reflect overall eating patterns, and the limited availability of stored plasma samples restricted measurement of additional mitochondrial microproteins.
These findings suggest that adherence to a Mediterranean diet may influence mitochondrial signaling pathways and is associated with lower oxidative stress, potentially contributing to its established cardioprotective effects.
“Mitochondrial microproteins may mediate the pro-longevity effects of the Mediterranean diet, serving as potential biomarkers of mitochondrial response to dietary interventions and opening new perspectives for precision nutrition strategies aimed at promoting healthy aging,” the researchers wrote.
The researchers reported no commercial or financial conflicts of interest. The paper also disclosed that one reviewer was organizing a Research Topic with an author and that Roberto Vicinanza was a Frontiers editorial board member at the time of submission.
Source: Frontiers in Nutrition
