A study on the immunoregulatory properties of camel milk derived lipids (Camelus dromedarius)

Abstract

Camel (Camelus dromedarius) milk is believed to have beneficial effects in inflammatory diseases such as diabetes, however, there are few studies reporting the immunoregulatory properties of the milk’s lipids. This study aimed to extract the lipid component from camel milk and investigate its ability to regulate macrophage inflammatory responses using the human macrophage derived cell-line, dTHP-1. Omani camel milk lipid was over 95% triglyceride (TG) with major saturated fatty acids (SFAs) identified as palmitic acid (35.28%), myristic acid (14.46%), stearic acid (7.40 %); and unsaturated (USFAs) oleic acid (19.31%) and palmitoleic acid (14.00%). These fatty acids were identified as fatty acid methyl esters and analysed by Gas Chromatography – Mass Spectrometer (GC-MS). The camel milk’s total lipids (TL) total free fatty acids (TFAs) and unsaturated free fatty acids (USFAs) significantly reduced glycated protein (gBSA) proinflammatory cytokine secretion (TNF-α, IL-1β, IL-18 and IL-6) by dTHP-1 cells. In addition the lipids down regulated gene expression of markers of the proinflammatory M1 macrophage phenotype CD86 but in contrast the lipids significantly enhanced markers of the M2 phenotype (CD206, CD163, Dectin-1, IL-1Ra, and IL-10. TL also enhanced the translocation of the p50/p50 homodimers of the nuclear transcription factor NF-κB, at the expense of p50/p65 heterodimer translocation. The lipids significantly down regulated the expression and activation of the inflammasome NLRP3/caspase-1/ASC assembly formation. Finally all the lipid componets up-regulated significantly expression of the Ten-Eleven Translocation-2 (TET-2) transcription regulator, linking their actions to this recently discovered regulator of the NLRP3 inflammasome. This study reports evidence that camel milk lipids are in-vitro highly immunoregulatory in macrophages and their consumption may be beneficial in inflammatory diseases such as diabetes.