Partially defatted rather than native poppy seeds beneficially alter lipid metabolism in rats fed a high-fat diet

Partially defatted poppy seeds, a by-product of poppy oil cold pressing, could be an interesting dietary supplement for obesity management. The aim of this study was to compare the effects of dietary supplementation with a small amount of native or partially defatted poppy seeds on gastrointestinal function and lipid metabolism in rats fed a high-fat diet. The defatted poppy seeds had, among others, lower fat content and higher fibre and protein content than native poppy seeds. The rats fed with a high-fat diet were characterised by severe metabolic disorders, especially in the liver, and poppy seeds were unable to prevent them. However, depending on the seed form, dietary supplementation with poppy seeds differentially affected the microbial and endogenous lipid metabolism in rats. In the distal intestine, both dietary seed forms stimulated microbial acetate production, and the supplementation with partially defatted poppy seeds additionally inhibited isobutyrate and isovalerate formation, which indicates a reduction in putrefaction. Both dietary seed forms increased cholesterol accumulation in the liver. Only dietary supplementation with partially defatted poppy seeds attenuated visceral fat and hepatic triglyceride accumulations and lowered blood triglyceride concentrations, and at the transcriptional level, the inhibition of SREBP-1c, which upregulates genes responsible for de novo lipogenesis, was additionally observed in this organ. In conclusion, a low and regular consumption of partially defatted poppy seeds may be beneficial in managing obesity-related disorders.