The Effect of Palmitate in the Expression of Ectonucleotidase CD73 and Inflammatory Markers in Murine Gingival Fibroblasts

OBJECTIVES: The goal of this study is to observe the effect of palmitate in the pro-inflammatory response of murine gingival fibroblasts in vitro and the levels of purine metabolizing enzyme CD73 which can ultimately control inflammation through modulation of mitochondrial health-related genes. METHODS: Murine gingival fibroblasts were extracted from C57BI/6J mice and used between 4th and 8th passages in vitro. Cells were stimulated with palmitate (200 mM) in the presence or absence of IL-1b stimulation and mRNA for inflammatory cytokines, mitochondrial health markers and CD73 were measured by RT-qPCR after 6 hours. RESULTS: The cytokines Cxcl1, IL-6 and Ccl2, but not chemokine Cxcl2, were significantly upregulated in the presence of palmitate in addition to IL-1b. The levels of CD73 were decreased in IL-1b-stimulated fibroblasts with palmitate only. Genes related to mitochondrial health such as Pink1, Mfn1, Mfn2 or Fis1 were not modulated in the presence of palmitate. CONCLUSIONS: Palmitate increased IL-1b-induced expression of inflammatory cytokines and decreased CD73 in murine gingival fibroblasts with no effect on mitochondrial health-related genes, at least at the mRNA level. IMPLICATIONS: This study implicates that there is further investigation needed to better understand the relationship of palmitate with CD73 and its effects on mitochondrial health and inflammation. Once the relationship is explored and defined, this research could be part of the first steps to support the development of biomarkers to detect periodontal inflammation early on and advance current preventive measures.