Olive Oil Extracts and Oleic Acid Attenuate the LPS-Induced Inflammatory Response in Murine RAW264.7 Macrophages but Induce the Release of Prostaglandin E2

Abstract

Olive oil contains high amounts of oleic acid (OA). Although OA has been described to inhibit inflammatory processes, the effects of olive oil on cellular mechanisms remain poorly understood. Therefore, we compared the effects of major fatty acids (FA) from olive oil with those of olive oil extracts (OOE) on inflammatory mediators and alterations in the cellular phospholipid composition in murine macrophages. Upon treatment with different OOE, FA compositions of lipopolysaccharide (LPS)-stimulated murine RAW264.7 macrophages were analyzed using gas chromatography. Olive oil extracts and OA significantly reduced the LPS-induced expression of inducible nitric oxide synthase (iNos), cyclooxygenase (Cox2), and interleukin-6 mRNA. In addition, a significant decrease in Cox2 and iNos protein expression was observed. The formation of nitric oxide was significantly reduced, while the formation of prostaglandin (PG) E2 from arachidonic acid significantly increased after treatment with OOE or OA. The latter was associated with a shift in the phospholipid FA composition from arachidonic acid to OA, resulting in an elevated availability of arachidonic acid. Together, OOE and OA mediate anti-inflammatory effects in vitro but increase the release of arachidonic acid and hereinafter PGE2, likely due to elongation of OA and competitive incorporation of fatty acids into membrane phospholipids.

Therapeutic hydrophobic deep eutectic solvents of menthol and fatty acid for enhancing anti-inflammation effects of curcuminoids and curcumin on RAW264.7 murine macrophage cells

“…OLA can reduce the LPS-induced expression of iNOS, COX-2, and IL-6 mRNA and significantly decrease COX-2 and iNOS protein expression. 35 Therefore, OLA : menthol can preserve cell viability and reduce inflammation. These results corroborate with several previous studies that demonstrated the low toxicity of DESs.…”

“…Through the activation of NF-kB, OLA is linked to COX-2 and iNOS downregulation. 34,35 At the 1 : 2, 1 : 1, and 2 : 1 molar ratios of fatty acid-: menthol, a decreasing trend of cell toxicity with high menthol proportion was observed. Menthol has immunomodulatory and anti-inammatory effects in ethanol-induced gastric ulcers, where it reduces the pro-inammatory cytokines, TNF-a, and IL-6, while increasing the levels of the anti-inammatory cytokine IL-10.…”

The Role of Diet in Regulation of Macrophages Functioning

“…The described effects of the MTD are based on a unique combination of high extra virgin olive oil (EVOO), oily-fish and vegetables consumption. EVOO has in vitro proven anti-inflammation effects of polyphenols on macrophages [ 36 , 37 ], including the reduction in NO release and iNOS expression. Fish oil in human studies represents the inhibition of inflammation-related genes expression in macrophages [ 38 ] and fresh vegetables, especially cruciferous, are pointed out by outstanding anti-inflammatory properties through biological-active compounds, which promote the M2 (anti-inflammatory) type of macrophage proliferation [ 39 ].…”

Testicular Immunity and Its Connection with the Microbiota. Physiological and Clinical Implications in the Light of Personalized Medicine

“…Probiotics by definition are “ live microorganisms which when administered in adequate amounts confer a health benefit on the host ” [ 131 , 132 ]. They have been used to enhance male reproduction, owing to their ability to protect the intestinal barrier, inhibit pathogen growth and activate the immune response [ 133 , 134 ].…”