RESUMEN
BACKGROUND: Palmitoleic acid (PA) is a n-7 monounsaturated fatty acid (MUFA) secreted by adipose tissue and related to decreased insulin resistance in peripheral tissues. Evidences have been shown that PA also decreased proinflammatory cytokine expression in cultured macrophages. Although studies have shown that other fatty acids (FAs) modulate several lymphocyte functions, the specific effect of PA on these cells is unknown. The aim of the present study was to evaluate the possible influence of PA on activation and differentiation of human lymphocytes in comparison to oleic acid (OA). METHODS: Human lymphocytes were isolated from peripheral blood of health men and cultured in the presence of growing concentrations of PA or OA (5 to 200 µM), for 24 h. After that, cells were collected and cytotoxicity evaluated by flow cytometry. Then, we analyzed proliferative capacity in lymphocytes treated with non toxic concentrations of PA and OA (25 and 50 µM, respectively), in the presence or absence of concanavalin A (ConA). The Th1/Th2/Th17 cytokine production was determined by the Cytometric Bead Array. CD28 and CD95 surface expression and T regulatory cell percentage were determined by flow cytometry. RESULTS: We observed that PA is toxic to lymphocytes above 50 µM. PA promoted a decrease of lymphocyte proliferation stimulated by ConA in both concentrations. PA also decreased CD28 externalization and increased CD95. On the other hand, OA did not alter these parameters. In the same way, PA reduced IL6, IFN-gamma, TNF-alpha and IL17A production in both concentration and IL2 only at 50 µM (in the presence of ConA). OA promoted IFN-gamma reduction in both concentrations and an increase of IL-2, IL4 and IL10 at 25 µM. Both fatty acids decreased the percentage of T regulatory cells. CONCLUSION: In conclusion, PA promoted a suppressive effect on lymphocyte proliferation characterized by a decrease of Th1 and Th17 response, and co-stimulatory molecule (CD28). However, OA increased lymphocyte proliferation through IL2 production and Th2 response. These results also show a more suppressive effect of PA on lymphocytes in comparison to OA.
Asunto(s)
Proliferación Celular/efectos de los fármacos , Citocinas/efectos de los fármacos , Ácidos Grasos Monoinsaturados/farmacología , Linfocitos/efectos de los fármacos , Adulto , Citometría de Flujo , Humanos , Activación de Linfocitos/efectos de los fármacos , Linfocitos/fisiología , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
Lipid emulsion (LE) containing medium/ω-6 long chain triglyceride-based emulsion (MCT/ω-6 LCT LE) has been recommended in the place of ω-6 LCT-based emulsion to prevent impairment of immune function. The impact of MCT/ω-6 LCT LE on lymphocyte and neutrophil death and expression of genes related to inflammation was investigated. Seven volunteers were recruited and infusion of MCT/ω-6 LCT LE was performed for 6 h. Four volunteers received saline and no change was found. Blood samples were collected before, immediately afterwards and 18 h after LE infusion. Lymphocytes and neutrophils were studied immediately after isolation and after 24 and 48 h in culture. The following determinations were carried out: plasma-free fatty acids, triacylglycerol and cholesterol concentrations, plasma fatty acid composition, neutral lipid accumulation in lymphocytes and neutrophils, signs of lymphocyte and neutrophil death and lymphocyte expression of genes related to inflammation. MCT/ω-6 LCT LE induced lymphocyte and neutrophil death. The mechanism for MCT/ω-6 LCT LE-dependent induction of leucocyte death may involve changes in neutral lipid content and modulation of expression of genes related to cell death, proteolysis, cell signalling, inflammatory response, oxidative stress and transcription.
Asunto(s)
Emulsiones Grasas Intravenosas/farmacología , Ácidos Grasos Omega-6/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Inflamación/genética , Leucocitos/citología , Leucocitos/efectos de los fármacos , Triglicéridos/farmacología , Adulto , Apoptosis/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Colesterol/sangre , Fragmentación del ADN , Ácidos Decanoicos/sangre , Regulación hacia Abajo/efectos de los fármacos , Regulación hacia Abajo/genética , Emulsiones Grasas Intravenosas/química , Emulsiones Grasas Intravenosas/metabolismo , Ácidos Grasos no Esterificados/análisis , Ácidos Grasos no Esterificados/sangre , Ácidos Grasos Omega-6/sangre , Ácidos Grasos Omega-6/química , Ácidos Grasos Omega-6/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/genética , Humanos , Recuento de Leucocitos , Leucocitos/metabolismo , Linfocitos/efectos de los fármacos , Linfocitos/metabolismo , Linfocitos/patología , Masculino , Necrosis/inducido químicamente , Necrosis/patología , Neutrófilos/efectos de los fármacos , Neutrófilos/patología , Ácidos Palmíticos/sangre , Ácidos Esteáricos/sangre , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo , Triglicéridos/sangre , Triglicéridos/química , Triglicéridos/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/genética , Adulto JovenRESUMEN
The purpose of this study was to verify the effects of short periods of exercise of different intensity on lymphocyte function and cytokines. Thirty Wistar rats, 2 months old, were used. They were divided into five groups of six rats: a sedentary control group; a group exercised for 5 minutes at low intensity (5 L); a group exercised for 15 minutes at low intensity (15 L); and groups exercised at moderate intensity (additional load of 5 % of body weight) for 5 minutes (5 M) or for 15 minutes (15 M). The parameters measured were: total leukocytes, neutrophils, lymphocytes, monocytes, lymphocytes from lymph nodes, serum cytokines (IL-2, IL-6 and TNF-alpha), lymphocyte mitochondrial transmembrane potential, viability and DNA fragmentation. ANOVA two way followed by Tukey's post hoc test (p Asunto(s)
Citocinas/sangre
, Linfocitos
, Condicionamiento Físico Animal/fisiología
, Animales
, Apoptosis
, Humanos
, Recuento de Leucocitos
, Monocitos
, Neutrófilos
, Ratas
, Ratas Wistar
, Factores de Tiempo
, Factor de Necrosis Tumoral alfa
RESUMEN
The change in cellular reducing potential, most likely reflecting an oxidative burst, was investigated in arachidonic acid- (AA) stimulated leukocytes. The cells studied included the human leukemia cell lines HL-60 (undifferentiated and differentiated into macrophage-like and polymorphonuclear-like cells), Jurkat and Raji, and thymocytes and macrophages from rat primary cultures. The oxidative burst was assessed by nitroblue tetrazolium reduction. AA increased the oxidative burst until an optimum AA concentration was reached and the burst decreased thereafter. In the leukemia cell lines, optimum concentration ranged from 200 to 400 æM (up to 16-fold), whereas in rat cells it varied from 10 to 20 æM. Initial rates of superoxide generation were high, decreasing steadily and ceasing about 2 h post-treatment. The continuous presence of AA was not needed to stimulate superoxide generation. It seems that the NADPH oxidase system participates in AA-stimulated superoxide production in these cells since the oxidative burst was stimulated by NADPH and inhibited by N-ethylmaleimide, diphenyleneiodonium and superoxide dismutase. Some of the effects of AA on the oxidative burst may be due to its detergent action. There apparently was no contribution of other superoxide-generating systems such as xanthine-xanthine oxidase, cytochromes P-450 and mitochondrial electron transport chain, as assessed by the use of inhibitors. Eicosanoids and nitric oxide also do not seem to interfere with the AA-stimulated oxidative burst since there was no systematic effect of cyclooxygenase, lipoxygenase or nitric oxide synthase inhibitors, but lipid peroxides may play a role, as indicated by the inhibition of nitroblue tetrazolium reduction promoted by tocopherol.
Asunto(s)
Animales , Masculino , Ratas , Humanos , Ácido Araquidónico , Depuradores de Radicales Libres , Leucocitos , Estallido Respiratorio , Superóxido Dismutasa , Indicadores y Reactivos , NADPH Oxidasas , Nitroazul de Tetrazolio , Células Tumorales CultivadasRESUMEN
The change in cellular reducing potential, most likely reflecting an oxidative burst, was investigated in arachidonic acid- (AA) stimulated leukocytes. The cells studied included the human leukemia cell lines HL-60 (undifferentiated and differentiated into macrophage-like and polymorphonuclear-like cells), Jurkat and Raji, and thymocytes and macrophages from rat primary cultures. The oxidative burst was assessed by nitroblue tetrazolium reduction. AA increased the oxidative burst until an optimum AA concentration was reached and the burst decreased thereafter. In the leukemia cell lines, optimum concentration ranged from 200 to 400 microM (up to 16-fold), whereas in rat cells it varied from 10 to 20 microM. Initial rates of superoxide generation were high, decreasing steadily and ceasing about 2 h post-treatment. The continuous presence of AA was not needed to stimulate superoxide generation. It seems that the NADPH oxidase system participates in AA-stimulated superoxide production in these cells since the oxidative burst was stimulated by NADPH and inhibited by N-ethylmaleimide, diphenyleneiodonium and superoxide dismutase. Some of the effects of AA on the oxidative burst may be due to its detergent action. There apparently was no contribution of other superoxide-generating systems such as xanthine-xanthine oxidase, cytochromes p-450 and mitochondrial electron transport chain, as assessed by the use of inhibitors. Eicosanoids and nitric oxide also do not seem to interfere with the AA-stimulated oxidative burst since there was no systematic effect of cyclooxygenase, lipoxygenase or nitric oxide synthase inhibitors, but lipid peroxides may play a role, as indicated by the inhibition of nitroblue tetrazolium reduction promoted by tocopherol.