Reduction of serum lipid levels in diabetic obese KK-Ay mice using monoalkyldiacylglycerol-rich oil derived from Berryteuthis magister

Monoalkyldiacylglycerol (MADG), an ether analog of triacylglycerols, is abundant in some marine animals such as deep-sea sharks and echinoderms. The present study aims to investigate the effects of an MADG-rich neutral lipid derived from Berryteuthis magister (MNB) on the lipid metabolism of diabetic/obese KK- A y mice. Male mice (5 weeks old) were fed soybean oil (control group), MNB, or fish oil (FO) which contain the same amount of EPA and DHA in the form of triacylglycerols. MNB or FO supplementation resulted in a decrease in adipose tissue weights and blood glucose levels compared to the control mice. Interestingly, serum lipid levels in the MNB group were significantly lower than those of the control and FO groups. Although there was no difference in EPA and DHA levels in the tissues between the FO and MNB groups, a decrease in the number of lipoprotein particles was characteristically observed in the mice fed with MNB. Our results suggest that the MADG structure-dependent effect on lipoprotein synthesis and/or secretion partly accounted for the reduced serum lipids in KK- A y mice by dietary MNB. This study advances the understanding of MADG as a nutraceutical and provides insights into the role of ether lipids in lipoprotein metabolism that can contribute to the development of prevention and treatment strategies for hyperlipidemia.