Dexamethasone inhibits and meloxicam promotes proliferation of bovine NK cells.
Due to the unrecognized effect of dexamethasone (DEX) and meloxicam (MEL) on bovine natural killer (NK) cells, studies have been undertaken in order to determine whether the above medications can affect these cells in respect of their counts, apoptosis, proliferation and production of selected cytokines. Peripheral blood mononuclear cells (PBMCs) were treated with the drugs in concentrations reflecting their plasma levels achieved in vivo at therapeutic doses and in 10-fold lower concentrations. The effect of DEX and MEL on percentages and absolute counts of NK cells was determined 6, 12, 48 and 168 h after the exposure of PBMCs to the drugs. At each time point, it was found out that DEX reduced the absolute count of NK cells, an effect attributed to the proapoptotic and anti-proliferative influence of the drug on these cells. DEX lowered the production of IFN-γ by the analyzed cells and raised the percentage of IL-10-producing cells. Thus, the above effects are important elements contributing to the complex mechanism responsible for the anti-inflammatory and immunosuppressive properties of the drug. MEL neither affects the apoptosis of NK cells nor did it reduce their count. Moreover, one-week exposure to MEL raised the absolute count of these cells, which was the result of their more intense proliferation in the presence of the drug. Thus, the influence of MEL with respect to the proliferation and count of NK cells was immunostimulating. On the other hand, MEL reduced the percentage of IFN-γ-producing NK cells, which in turn is an immunosuppressive effect.
Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, University of Warmia and Mazury, Olsztyn, Poland. tomasz.maslanka@uwm.edu.pl
Tomasz
T
Maślanka
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects / Q000276:immunology; D002417:Cattle; D048708:Cell Growth Processes / Q000187:drug effects; D003907:Dexamethasone / Q000276:immunology / Q000494:pharmacology*; D007166:Immunosuppressive Agents / Q000494:pharmacology; D007371:Interferon-gamma / Q000276:immunology; D016753:Interleukin-10 / Q000276:immunology; D007694:Killer Cells, Natural / Q000166:cytology / Q000187:drug effects* / Q000276:immunology; D007963:Leukocytes, Mononuclear / Q000166:cytology / Q000187:drug effects / Q000276:immunology; D000077239:Meloxicam; D013843:Thiazines / Q000276:immunology / Q000494:pharmacology*; D013844:Thiazoles / Q000276:immunology / Q000494:pharmacology*
D000893:Anti-Inflammatory Agents; D007166:Immunosuppressive Agents; D013843:Thiazines; D013844:Thiazoles; D016753:Interleukin-10; D003907:Dexamethasone; D007371:Interferon-gamma; D000077239:Meloxicam