Medium Chain Triglyceride (MCT) Oil Affects the Immunophenotype via Reprogramming of Mitochondrial Respiration in Murine Macrophages

Medium chain triglyceride (MCT) oil has been postulated to modulate inflammatory responses, but the detailed mechanisms have not been fully elucidated. Based on recent studies demonstrating that mitochondrial metabolic reprogramming and immune responses are correlated, the current study sought to determine whether MCT oil controls inflammatory responses through modulation of mitochondria using both in vitro and in vivo models. The mitochondrial metabolic phenotypes of macrophages were assessed according to oxygen consumption rate (OCR). Inflammatory responses were assessed for production of cytokines and expression of activation markers. MCT oil was more rapidly oxidized as observed by increased OCR in macrophages. The production of pro-inflammatory cytokines was down-regulated and anti-inflammatory cytokine was elevated by MCT oil. In addition, classically activated M1 and alternatively activated M2 markers were reciprocally regulated by MCT intervention. Overall, up-regulated β-oxidation by MCT contributes to the anti-inflammatory M2-like status of macrophages, which may aid in the dietary prevention and/or amelioration of inflammation.