Int J Vitam Nutr Res., 2019., Nov 8:1-9. doi: 10.1024/0300-9831/a000612.

Flaxseed and evening primrose oil slightly affect systolic and diastolic function of isolated heart in male but not in female rats.

Andjic M Draginic N Radoman K et al.

Abstract

Considering that sex related differences in cardiac response to flaxseed (FSO) and evening primrose oil (EPO) are insufficiently known present investigation assessed the effect of these two oils, on the cardiac function of isolated rat hearts and the possible role of sex in this. The present study was carried out on 60 adult male Wistar albino rats randomly divided into 6 groups: male rats treated with EPO, dose of 10 mg/kg/day; female rats treated with EPO, dose of 10 mg/kg/day; male rats treated with FSO, dose of 300 mg/kg/day; female rats treated with FSO, dose of 300 mg/kg/day; control group of female rats treated with regular laboratory diet for animals; control group of male rats treated with regular laboratory diet for animals. Using the Langendorff technique, markers of the heart function were evaluated: the maximum and minimum rates of pressure development in the left ventricle (LV; dP/dtmax, dP/dtmin), systolic and diastolic left ventricular pressure (SLVP, DLVP, respectively), heart rate (HR) and coronary flow (CF). Male rats treated with EPO had significantly higher (p = 0.016) mean values of dP/dtmax, dP/dtmin, SLVP and DLVP (average increase for all CPPs 20%, 25%, 30% and 110%, respectively), compared to the group of male rats treated with FSO (p = 0.914). Our study results indicate that both types of PUFA oils only slightly changed the function of the isolated rat heart in male but not in female rats. Nevertheless, the difference between oil treatments was found in male rats who had stronger cardiac response after supplementation with EPO.

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Key Points

The aim of the current investigation was to assess the effects of FSO and EPO by comparing the influence of their main components (ALA vs LA/GLA) on the cardiac function of rat heart and also to identify possible differences related to the rat sex. The authors measured and evaluated the differences between the effects of these two plant oils on the cardiac function after 6 weeks of treatment by using various cardiodynamic markers (dP/dt max, dP/dt min, SLVP, DLVP, HR and CF). Taken together, treatment with both oils only slightly changed cardiac function compare to rats without diets enriched with these PUFAs (ALA or LA and GLA). In addition, in male rats supplementation with EPO was connected with higher cardiodynamic values (contractillity parameters, SLVP and DLVP) compare to FSO, while in female rats no differences were observed. Coronary perfusion were left unaffected after supplementation with EPO and FSO oils in both sexes. Supplementation with FSO and EPO was associated with only slightly changed cardiac function in male rats. The only difference between oil treatments was stronger cardiac response after supplementation with EPO in male rats. Findings of the present study may help in better understanding of the cardiac effects of flaxseed and evening primrose oils. It can be concluded that both types of PUFA oils only slightly changed the function of the isolated rat heart in male but not in female rats. The difference between oil treatments was found in male rats who had stronger cardiac response after supplementation with EPO.