engleski

Fatty acid composition of heart muscle in free- ranging brown bears from Croatia

Heart muscle is a specific organ in the body that performs continuous work and requires continuous energy supply which includes oxidation of fatty acids (FA). The storage of lipids in heart is small, and FAs are available from the diet and fat depots. Literature states that FA profile of heart, as compared to other muscles and fat, is characterised by a high contribution of polyunsaturated FA (PUFA). Several recent studies in humans and in animal models showed that males (M) and females (F) differ in the composition of cell membrane and plasma phospholipids. To our knowledge FA composition of brown bear heart muscle was not investigated, therefore that was the objective of this study. The study was conducted on 30 free-ranging brown bears from Croatia (15 F, 15 M ; 14 subadult, 16 adult) sampled during 2017. Tissue samples were homogenized, and total lipids extracted, then FA composition was determined by gas chromatography. Heart muscle lipids were dominated by PUFA (F, 41.75±9.1% vs. M, 35.3±4.7%, p<0.05), followed by monounsaturated FA (MUFA, 38.8±7.3% vs. 44.5±6.2%, p<0.05), and finally saturated FA (SFA, 19.4±3.4% vs. 20.2±3.4%, p>0.05). Subadult females had significantly higher percentage of n-3 PUFA compared to subadult males (18.1±1.6% vs. 14.85±4.2%). However, females from Gorski kotar region had significantly lower percentage of docosahexaenoic (DHA, C22:6n-3) acid, (0.3±0.2% vs. 0.6±0.2%), compared to males. Furthermore, compared to males, females had significantly lower percentage of DHA in autumn (0.2±0.2% vs. 0.7±0.01%), as well as C18:1n-9, MUFA and PUFA in spring (19.2±4.7% vs. 24.8±4.9% ; 36.3±7.2% vs. 43.1±4.6% ; 44.8±10.5% vs. 36.6±3.2%). These findings imply that differences in the heart FA composition could be due to differences in gender, season, habitat, and the supply of FA from the diet and fat depots. The results present valuable contribution for better understanding of heart muscle physiology.

fatty acid ; heart ; brown bear

nije evidentirano