Modulation of peritoneal macrophage activity by the saturation state of the fatty acid moiety of phosphatidylcholine

Abstract

To determine the effects of saturated and unsaturated fatty acids in phosphatidylcholine (PC) on macrophage activity, peritoneal lavage cells were cultured in the presence of phosphatidylcholine rich in saturated or unsaturated fatty acids (sat PC and unsat PC, respectively), both used at concentrations of 32 and 64 μM. The treatment of peritoneal macrophages with 64 μM unsat PC increased the production of hydrogen peroxide by 48.3% compared to control (148.3 ± 16.3 vs 100.0 ± 1.8%, N = 15), and both doses of unsat PC increased adhesion capacity by nearly 50%. Moreover, 64 μM unsat PC decreased neutral red uptake by lysosomes by 32.5% compared to the untreated group (67.5 ± 6.8 vs 100.0 ± 5.5%, N = 15), while both 32 and 64 μM unsat PC decreased the production of lipopolysaccharide-elicited nitric oxide by 30.4% (13.5 ± 2.6 vs 19.4 ± 2.5 μM) and 46.4% (10.4 ± 3.1 vs 19.4 ± 2.5 μM), respectively. Unsat PC did not affect anion production in non-stimulated cells or phagocytosis of unopsonized zymosan particles. A different result pattern was obtained for macrophages treated with sat PC. Phorbol 12-miristate 13-acetate-elicited superoxide production and neutral red uptake were decreased by nearly 25% by 32 and 64 μM sat PC, respectively. Sat PC did not affect nitric oxide or hydrogen peroxide production, adhesion capacity or zymosan phagocytosis. Thus, PC modifies macrophage activity, but this effect depends on cell activation state, fatty acid saturation and esterification to PC molecule and PC concentration. Taken together, these results indicate that the fatty acid moiety of PC modulates macrophage activity and, consequently, is likely to affect immune system regulation in vivo.

Eugenia unifloraL. Essential Oil as a Potential Anti-LeishmaniaAgent: Effects onLeishmania amazonensisand Possible Mechanisms of Action

“…Measurement of the lysosomal activity was carried out according to the method of Grando et al [28]. Peritoneal macrophages were plated and incubated with EuEO in serial dilutions of 100, 50, 25, 12.5, 6.25, and 3.12  μ g·mL −1 .…”

“…The supernatant was removed and added to 100 mL of extraction solution. After solubilization in a Kline shaker, the absorbances were measured at 550 nm by using an ELISA plate reader [28]. …”

“…At the time of dosing, 100  μ L of either the samples or the solutions prepared for obtaining the standard curve was mixed with an equal volume of Griess reagent. The analysis was performed using an ELISA plate reader at 550 nm [28]. …”

Platonia insignis Mart., a Brazilian Amazonian Plant: The Stem Barks Extract and Its Main Constituent Lupeol Exert Antileishmanial Effects Involving Macrophages Activation

“…Then, NR was solubilized by adding the extraction solution (see Section 2.10.1 ) in the Kline shaker. The absorbance was subsequently measured at 550 nm as above [ 17 ].…”

In Vivo and Cytotoxicity Evaluation of Repaglinide-Loaded Binary Solid Lipid Nanoparticles After Oral Administration to Rats

“…28,29 MTT was dissolved in phosphate buffer saline at a concentration of 5.0 mg/mL. Twenty microlitres of the MTT solution was added into each 96-culture well containing 1 × 10 5 cells/100 :L after treatment with different doses (0.4, 0.6, 0.8, 1.0 and 1.2 mg/mL) of nanosuspension and RG control for 24 h and then incubated at 37 • C for further 4 h. The plate was centrifuged for 5 min at 100 g at 4 • C and the untransformed MTT was removed carefully by pipetting without disturbing the dark blue formazan (formed by cellular reduction of tetrazolium salt).…”