Dietary Sphingolipids Ameliorate Disorders of Lipid Metabolism in Zucker Fatty Rats

Abstract

Dietary sphingolipids (SL) inhibit colon carcinogenesis, reduce serum cholesterol, and improve skin barrier function and are considered to be "functional lipids". For comparative determination of the effects of SL with different chemical compositions on lipid metabolism and its related hepatic gene expression, Zucker fatty rats were fed pure sphingomyelin (SM) of animal origin and glucosylceramide (GC) of plant origin. After 45 days, the SM and GC diets led to significant reductions in hepatic lipid and plasma non-HDL cholesterol. Both SM and GC diets decreased plasma insulin levels, whereas only the GC diet increased the plasma adiponectin level. Hepatic gene expression analysis revealed increased expression of adiponectin receptor 2 (Adipor2), peroxisome proliferator-activated receptor alpha (PPARalpha), and pyruvate dehydrogenase kinase 4 (Pdk4). However, expression of stearoyl CoA desaturase (Scd1) was significantly decreased. These results suggest that dietary SL, even of different origins and chemical compositions, may prevent fatty liver and hypercholesterolemia through improvement of adiponectin signaling and consequent increases in insulin sensitivity.

Compounds of the sphingomyelin-ceramide-glycosphingolipid pathways as secondary messenger molecules: new targets for novel therapies for fatty liver disease and insulin resistance

“…Both SM and GC diets decreased plasma insulin levels, and the GC diet increased the plasma adiponectin level. These effects were associated with increased expression of adiponectin receptor 2, PPAR␣, and pyruvate dehydrogenase kinase 4 and with a decreased in the expression of stearoyl CoA desaturase (156,182,186).…”

“…The effect was associated with increased plasma level of the appetite-regulating peptide YY (96,100,171). The L-ido derivative of 2,L-ido-AMP-DNM, a selective inhibitor of GSL synthesis, lowered visceral GSLs in ob/ob mice and ZDF rats, with no inhibition of sucrase activity or sucrose assimilation being less effective in reducing blood glucose and HbA1c (172,178,182).…”

Potential role of milk fat globule membrane in modulating plasma lipoproteins, gene expression, and cholesterol metabolism in humans: a randomized study

“…Bovine MFGM consists of w70% lipids and w20% proteins (16). Animal studies showed that MFGM and sphingolipids could lower plasma cholesterol partly by modulating hepatic gene expression (17)(18)(19)(20)(21)(22). The content and physical structure of MFGM are differentially preserved in dairy products.…”

Potential health benefits of sphingolipids in milk and dairy products

“…Duivenvoorden et al (2006) reported that dietary sphingolipids play an important role in lowering plasma cholesterol and triacylglycerol and protecting the liver from fat-and cholesterol-induced steatosis. In addition, through the promotion of adiponectin signaling, dietary sphingolipids inhibit fatty liver, hipercholesterolemia, and insulin resistance (Yunoki et al, 2010;Bamba et al, 2012). It may be concluded that dietary sphingolipids hold great potential to treat multiple aspects of the metabolic syndrome, such as dyslipidemia, insulin resistance and cardiovascular diseases.…”