RESUMO
Isoflavonoids have been largely studied due to their distinct biological activities identified thus far. Herein, we evaluated the activity of neovestitol, an isoflavonoid isolated from Brazilian red propolis, in acute and chronic inflammation. As for acute inflammation, we found that neovestitol reduced neutrophil migration, leukocyte rolling and adhesion, as well as expression of ICAM-1 in the mesenteric microcirculation during lipopolysaccharide-induced acute peritonitis. No changes were observed in the levels of TNF-α, CXCL1/KC and CXCL2/MIP-2 upon pretreatment with neovestitol. The administration of an inducible nitric oxide synthase (iNOS) inhibitor abolished the inhibitory effects of neovestitol in neutrophil migration and ICAM-1 expression. Nitrite levels increased upon treatment with neovestitol. No effects of neovestitol were observed on the chemotaxis of neutrophils in vitro. As for chronic inflammation, neovestitol also reduced the clinical score and joint damage in a collagen-induced arthritis model. There was no change in the frequency of IL-17-producing TCD4+ cells. In addition, pretreatment with neovestitol reduced the levels of IL-6. These results demonstrate a potential anti-inflammatory activity of neovestitol, which may be useful for therapeutic purposes and/or as a nutraceutical.
Assuntos
Artrite Experimental/prevenção & controle , Flavonoides/uso terapêutico , Interleucina-6/metabolismo , Óxido Nítrico/metabolismo , Peritonite/prevenção & controle , Própole/química , Doença Aguda , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Artrite Experimental/etiologia , Brasil , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Doença Crônica , Citocinas/metabolismo , Flavonoides/química , Flavonoides/farmacologia , Guanidinas/farmacologia , Lipopolissacarídeos/toxicidade , Veias Mesentéricas/efeitos dos fármacos , Veias Mesentéricas/metabolismo , Veias Mesentéricas/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Neutrófilos/citologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Peritonite/etiologia , Própole/metabolismoRESUMO
The mechanisms whereby testosterone increases cardiovascular risk are not clarified. However, oxidative stress and inflammation seem to be determinants. Herein, we sought to determine whether exogenous testosterone, at physiological levels, induces leucocyte migration, a central feature in immune and inflammatory responses and the mediating mechanisms. We hypothesized that testosterone induces leucocyte migration via NADPH oxidase (NADPHox)-driven reactive oxygen species (ROS) and cyclooxygenase (COX)-dependent mechanisms. Sixteen-week-old Wistar rats received an intraperitoneal injection (5 ml) of either testosterone (10(-7) mol/l) or saline. Rats were pre-treated with 5 ml of sodium salicylate (SS, non-selective COX inhibitor, 1.25 × 10(-3) mol/l, 1 h prior to testosterone or saline), flutamide (androgen receptor antagonist, 10(-5) mol/l), apocynin (NADPHox inhibitor, 3 × 10(-4) mol/l), N-[2-Cyclohexyloxy-4-nitrophenyl]methanesulfonamide (NS398, COX2 inhibitor, 10(-4) mol/l) or saline, 4 h before testosterone or saline administration. Leucocyte migration was assessed 24 h after testosterone administration by intravital microscopy of the mesenteric bed. Serum levels of testosterone were measured by radioimmunoassay. NADPHox activity was assessed in membrane fractions of the mesenteric bed by dihydroethidium (DHE) fluorescence and in isolated vascular smooth muscle cells (VSMC) by HPLC. NADPHox subunits and VCAM (vascular cell adhesion molecule) expression were determined by immunoblotting. Testosterone administration did not change serum levels of endogenous testosterone, but increased venular leucocyte migration to the adventia, NADPHox activity and expression (P < 0.05). These effects were blocked by flutamide. SS inhibited testosterone-induced leucocyte migration (P<0.05). Apocynin and NS398 abolished testosterone-induced leucocyte migration and NADPHox activity (P<0.05). Testosterone induces leucocyte migration via NADPHox- and COX2-dependent mechanisms and may contribute to inflammatory processes and oxidative stress in the vasculature potentially increasing cardiovascular risk.
Assuntos
Movimento Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Leucócitos/efeitos dos fármacos , NADPH Oxidases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Testosterona/farmacologia , Acetofenonas/farmacologia , Androgênios/farmacologia , Animais , Western Blotting , Células Cultivadas , Inibidores Enzimáticos/farmacologia , Injeções Intraperitoneais , Leucócitos/citologia , Leucócitos/metabolismo , Masculino , Veias Mesentéricas/citologia , Veias Mesentéricas/efeitos dos fármacos , Veias Mesentéricas/metabolismo , Microscopia de Vídeo/métodos , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , NADPH Oxidases/antagonistas & inibidores , Nitrobenzenos/farmacologia , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Sulfonamidas/farmacologia , Superóxidos/metabolismo , Testosterona/administração & dosagemRESUMO
This study investigated the endothelium-dependent vasorelaxant effects of the essential oil of Ocimum gratissimum (EOOG) in aortas and mesenteric vascular beds isolated from rats. EOOG (3-300 µg/mL) relaxed the tonic contractions induced by phenylephrine (0.1 µmol/L) in isolated aortas in a concentration-dependent manner in both endothelium-containing and endothelium-denuded preparations. This effect was partially reversed by L-NAME (100 µmol/L) but not by indomethacin (10 µmol/L) or TEA (5 mmol/L). In mesenteric vascular beds, bolus injections of EOOG (30, 50, 100, and 300 ng) decreased the perfusion pressure induced by noradrenaline (6 µmol/L) in endothelium-intact preparations but not in those treated with deoxycholate. L-NAME (300 µmol/L) but not TEA (1 mmol/L) or indomethacin (3 µmol/L) significantly reduced the vasodilatory response to EOOG at all of the doses tested. Our data showed that EOOG exerts a dose-dependent vasodilatory response in the resistance blood vessels of rat mesenteric vascular beds and in the capacitance blood vessel, the rat aorta. This action is completely dependent on endothelial nitric oxide (NO) release in the mesenteric vascular beds but only partially dependent on NO in the aorta. These novel effects of EOOG highlight interesting differences between resistance and capacitance blood vessels.
Assuntos
Aorta Torácica/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Artérias Mesentéricas/efeitos dos fármacos , Veias Mesentéricas/efeitos dos fármacos , Ocimum/química , Óleos Voláteis/farmacologia , Vasodilatadores/farmacologia , Animais , Aorta Torácica/enzimologia , Aorta Torácica/metabolismo , Inibidores de Ciclo-Oxigenase/farmacologia , Endotélio Vascular/fisiologia , Técnicas In Vitro , Masculino , Artérias Mesentéricas/enzimologia , Artérias Mesentéricas/metabolismo , Veias Mesentéricas/enzimologia , Veias Mesentéricas/metabolismo , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Norepinefrina/antagonistas & inibidores , Norepinefrina/metabolismo , Óleos Voláteis/química , Bloqueadores dos Canais de Potássio/farmacologia , Ratos , Ratos Wistar , Capacitância Vascular/efeitos dos fármacos , Resistência Vascular/efeitos dos fármacos , Vasoconstritores/antagonistas & inibidores , Vasoconstritores/farmacologia , Vasodilatação/efeitos dos fármacos , Vasodilatadores/antagonistas & inibidoresRESUMO
This study analyzes the effects of sodium tungstate and vanadyl sulphate in the fructose-overloaded rat, a model of metabolic syndrome. Fructose (9 weeks) increased blood pressure, triglycerydemia, glycemia, and reduced release of vasodilator prostaglandins (prostacyclin and prostaglandin E2 ) in the mesenteric vascular bed. Sodium tungstate prevented those alterations; meanwhile vanadyl sulfate only prevented the increase in glycemia. In conclusion, the present experiments showed that sodium tungstate is more effective than vanadyl sulfate for the treatment of experimental metabolic syndrome in rats.
Assuntos
6-Cetoprostaglandina F1 alfa/biossíntese , Pressão Sanguínea/efeitos dos fármacos , Dinoprostona/biossíntese , Síndrome Metabólica/tratamento farmacológico , Compostos de Tungstênio/farmacologia , Compostos de Vanádio/farmacologia , Animais , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/metabolismo , Glicemia/análise , Determinação da Pressão Arterial , Cromatografia de Fase Reversa , Modelos Animais de Doenças , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Frutose/administração & dosagem , Frutose/metabolismo , Hipertensão/fisiopatologia , Hipertensão/prevenção & controle , Masculino , Artérias Mesentéricas/efeitos dos fármacos , Artérias Mesentéricas/metabolismo , Veias Mesentéricas/efeitos dos fármacos , Veias Mesentéricas/metabolismo , Síndrome Metabólica/metabolismo , Síndrome Metabólica/fisiopatologia , Ratos , Ratos Sprague-Dawley , Fatores de Risco , Triglicerídeos/sangueRESUMO
BACKGROUND: In previous studies we reported an altered prostanoid (PR) release-pattern in mesenteric vessels in fructose (F)-overloaded rats, an experimental model of insulin resistance and hypertension. Dehydroepiandrosterone (DHEA) and its precursor Dehydroepiandrosterone sulfate (DHEA-S) are the most abundant circulating steroid hormones produced by the adrenal and recent studies in both cells and animals suggest that DHEA may have acute non-genomic actions that mimic both metabolic and vascular actions of insulin. AIM OF THE STUDY: This study was to analyze in F-overloaded rats, the effects of DHEA treatment on arterial blood pressure and the PR production in mesenteric vessels and aorta. METHODS: Male 6 week-old Sprague-Dawley rats were randomly divided in four groups: a control group (C), a DHEA (30 mg/kg/sc/48 h)-treated group (D), a fructose (10% w/v in drinking water)-fed group (F), and both treatments simultaneously group (FD). The systolic blood pressure (SBP) was measured by tail cuff method and glycemia and triglyderidemia were measured by enzymatic assays. The mesenteric beds of all groups were dissected, and incubated in Krebs solution. The PR released were measured by HPLC. RESULTS: F overload increased SBP and triglyceridemia and decreased the mesenteric vasodilatory PR release. DHEA treatment prevented the increment in SBP and triglyceridemia and decreased vasoconstrictor PR in F-treated rats. CONCLUSION: DHEA normalize the PGI(2)/TX ratio, diminished in F-overloaded rats, through the decrease in thromboxane (TX) production and this could be one of the mechanisms by which DHEA prevented the slight hypertension in F-animals.
Assuntos
Pressão Sanguínea/efeitos dos fármacos , Desidroepiandrosterona/farmacologia , Prostaglandinas/metabolismo , Tromboxanos/sangue , Triglicerídeos/sangue , Administração Oral , Animais , Pressão Sanguínea/fisiologia , Desidroepiandrosterona/análogos & derivados , Desidroepiandrosterona/metabolismo , Modelos Animais de Doenças , Frutose/farmacologia , Hipertensão/induzido quimicamente , Hipertensão/prevenção & controle , Masculino , Artérias Mesentéricas/efeitos dos fármacos , Artérias Mesentéricas/metabolismo , Veias Mesentéricas/efeitos dos fármacos , Veias Mesentéricas/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Vasodilatação/efeitos dos fármacos , Vasodilatação/fisiologiaRESUMO
1. The administration of streptozotocin (STZ) to 2-day old rats induced a non-insulin-dependent diabetes mellitus (NIDDM)-like state, with mild hyperglycaemia and no alterations in body weight at the adult age. 2. In the isolated and perfused mesenteric vascular bed of NIDDM animals, the constrictor responses to either noradrenaline (NA) or potassium chloride (KCl) were not modified as compared with age-matched non-diabetic controls. 3. The reduction in NA contractions induced by the cyclooxygenase inhibitor, 10 microM indomethacin in the control group was absent in the NIDDM rats. 4. The increase in the NA-induced contractions caused by endothelium removal was suppressed by indomethacin in the controls but not in the NIDDM group. 5. The prostanoid release from the mesenteric vascular beds of NIDDM rats was markedly reduced as compared with non-diabetic controls. Noradrenaline increased production of the constrictor prostaglandin (PG) F2alpha in control but not in NIDDM rats. 6. In summary, these results show that in STZ-induced NIDDM rats, there is an impairment of the prostanoid production, as well as a suppression of the role of prostanoids in the contractile effects of NA in the mesenteric vascular bed. These alterations are more severe than those previously observed in a model of insulin-dependent diabetes mellitus (IDDM), in which hyperglycaemia and reduction of body weight were more marked. The conclusion is that, in these models of diabetes and in the preparation studied, vascular alterations and modifications of glycaemia and body weight are not closely related.
Assuntos
Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Artérias Mesentéricas/efeitos dos fármacos , Veias Mesentéricas/efeitos dos fármacos , Norepinefrina/farmacologia , Prostaglandinas/metabolismo , Vasoconstrição/efeitos dos fármacos , Vasoconstritores/farmacologia , Animais , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Tipo 2/induzido quimicamente , Masculino , Artérias Mesentéricas/metabolismo , Veias Mesentéricas/metabolismo , Prostaglandinas/biossíntese , Ratos , Ratos Wistar , Vasoconstrição/fisiologiaRESUMO
The roles of nitric oxide and of endothelium in the effects of the vasorelaxing agents acetylcholine and bradykinin on the production of prostanoids was studied in the isolated and perfused mesenteric vascular bed of the rat. Prostanoids were measured in the perfusate by high-performance liquid chromatography (HPLC). In the intact vascular bed, 1 microM bradykinin increased the release of 6-keto-prostaglandinF(1alpha) (stable metabolite of prostacyclin) and of prostaglandin E2 and 10 microM acetylcholine stimulated the efflux of prostacyclin only. In the de-endothelialized vascular bed, bradykinin increased the release of prostacyclin whereas acetylcholine increased the efflux of thromboxane. The inhibition of nitric oxide synthesis with 100 microM N(G)-nitro-L-arginine methyl ester prevented the effect of bradykinin but did not modify the effects of acetylcholine on prostanoid release. In addition, 100 microM L-arginine reversed the inhibitory effect of N(G)-nitro L-arginine methyl ester on bradykinin-stimulated prostaglandin production. It is concluded that acetylcholine and bradykinin stimulate prostanoid release in the rat mesenteric vascular bed with different patterns and through different mechanisms.