Dietary Sphingomyelin Attenuates Adipose Inflammation and Skeletal Muscle Lipid Accumulation in C57BL/6J Mice Fed an Obesogenic Diet

Abstract

Obesity continues to be endemic in the United States. Obesity leads to adipocyte enlargement and inflammation which manifests in metabolic dysfunction of the skeletal muscle and liver. Pharmacologically inhibiting lipid absorption has proven effective in managing obesity related weight gain and metabolic dysfunction. However, the current therapies are not without side effects and thus alternative treatments could prove beneficial. Sphingomyelin (SM) is a sphingolipid found in animal products, including milk and eggs. Dietary SM ingestion has been shown to reduce cholesterol and triglyceride absorption in rodents. The length of SM's amide‐linked fatty acid chain varies depending on the source of SM; therefore, SM from different sources may have different bioactivities. In the current study, C57BL/6J mice (N = 52) were divided into 4 diet groups and fed for 10 weeks either a low fat control diet (10% kcal from fat) (LFD, n = 10), an obesogenic high fat, high cholesterol diet (60% kcal as fat, 0.15% added cholesterol) (HFD, n = 14), or the HFD supplemented with either 0.1% (w/w) egg‐derived SM (HFESM, n = 14) or bovine milk‐derived SM (HFMSM, n = 14). The mice were examined for adipose inflammation and muscle lipid metabolism. HFESM had significantly lower body weight, less epididymal adipose crown‐like structures and lower triglyceride accumulation in the skeletal muscle compared to HFD. We also observed reductions in the mRNA expression of adipose inflammatory genes and skeletal muscle β‐oxidation genes in both the HFESM and HFMSM groups compared to HFD. The current data suggests SM may be an effective means of attenuating some of the metabolic dysfunction that accompanies obesity in high fat diet‐induced obese mice. More research is warranted to elucidate the mechanism of how dietary SM achieves these effects.Support or Funding InformationSupported by the University of Connecticut.