dinoprost and acetovanillone

Ex vivo lung perfusion (EVLP) allows perfusion and reconditioning of retrieved lungs for organ transplantation. The Steen solution is specifically designed for this procedure but the mechanism through which it elicits its activity is still to be fully clarified. We speculated that Steen solution may encompass antioxidant properties allowing a reestablishment of pulmonary tissue homeostasis. Blood samples from 10 healthy volunteers were recruited. Platelets and white cells were incubated with Steen solution or buffer solution as control and stimulated with suitable agonists. Reactive oxidant species (ROS), soluble NOX2 (sNOX2-derived peptide), a marker of NADPH oxidase activation, p47(phox) translocation to cell membrane and isoprostanes production, as marker of oxidative stress, and nitric oxide (NO), a powerful vasodilator and antioxidant molecule, were measured upon cell stimulation. The Steen solution significantly inhibited p47(phox) translocation and NOX2 activation in platelets and white cells. Consistent with this finding was the reduction of oxidative stress as documented by a significantly lowered formation of ROS and isoprostanes by both platelets and white cells. Finally, cell incubation with Steen solution resulted in enhanced generation of NO. Herewith, we provide the first evidence that Steen solution possesses antioxidant properties via downregulation of NADPH oxidase activity and enhanced production of NO.

Topics: Acetophenones; Adult; Antioxidants; Blood Platelets; Dextrans; Dinoprost; Down-Regulation; Female; Humans; Isoprostanes; Isotonic Solutions; Leukocytes; Male; Membrane Glycoproteins; NADPH Oxidase 2; NADPH Oxidases; Nitric Oxide; Reactive Oxygen Species; Serum Albumin

This study evaluates a possible relationship between reactive oxygen species (ROS) and cyclooxygenase (COX)-2-derived products in conductance and resistance arteries from hypertensive animals. Angiotensin II (Ang II)-infused mice or spontaneously hypertensive rats treated with the NAD(P)H Oxidase inhibitor apocynin, the mitochondrion-targeted SOD2 mimetic Mito-TEMPO, the superoxide dismutase analog tempol, or the COX-2 inhibitor Celecoxib were used.. Apocynin, Mito-TEMPO, and Celecoxib treatments prevented Ang II-induced hypertension, the increased vasoconstrictor responses to phenylephrine, and the reduced acetylcholine relaxation. The NOX-2 inhibitor gp91ds-tat, the NOX-1 inhibitor ML171, catalase, and the COX-2 inhibitor NS398 abolished the ex vivo effect of Ang II-enhancing phenylephrine responses. Antioxidant treatments diminished the increased vascular COX-2 expression, prostanoid production, and/or participation of COX-derived contractile prostanoids and thromboxane A(2) receptor (TP) in phenylephrine responses, observed in arteries from hypertensive models. The treatment with the COX-2 inhibitor normalized the increased ROS production (O(2)·(-) and H(2)O(2)), NAD(P)H Oxidase expression (NOX-1, NOX-4, and p22phox) and activity, MnSOD expression, and the participation of ROS in vascular responses in both hypertensive models. Apocynin and Mito-TEMPO also normalized these parameters of oxidative stress. Apocynin, Mito-TEMPO, and Celecoxib improved the diminished nitric oxide (NO) production and the modulation by NO of phenylephrine responses in the Ang II model.. This study provides mechanistic evidence of circuitous relationship between COX-2 products and ROS in hypertension.. The excess of ROS from NAD(P)H Oxidase and/or mitochondria and the increased vascular COX-2/TP receptor axis act in concert to induce vascular dysfunction and hypertension.

Topics: Acetophenones; Animals; Antioxidants; Aorta; Celecoxib; Cyclooxygenase 1; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Dinoprost; Endothelium, Vascular; Hypertension; In Vitro Techniques; Male; Mice; Mice, Inbred C57BL; Nitric Oxide; Oxidative Stress; Phenylephrine; Pyrazoles; Rats; Rats, Inbred SHR; Rats, Inbred WKY; Reactive Oxygen Species; Sulfonamides; Vasoconstrictor Agents; Vasodilation; Vasodilator Agents

Salt-induced hypertension in the Dahl rat is associated with increases in angiotensin II, aldosterone, free radical generation and endothelial dysfunction. However, little is known about the specific mechanism(s) associated with the end-organ damage effects of aldosterone. We hypothesised that eplerenone reduces kidney damage by blocking nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity.. Dahl salt-sensitive rats fed either a low-salt (LS) or high-salt (HS) diet were treated with aldosterone in the presence of eplerenone or apocynin. Indirect blood pressure was measured prior to start of diet and weekly thereafter. Levels of plasma nitric oxide (NO) and urinary 8-isoprostane were measured following treatment. Protein levels of selected subunits of NADPH were assessed by western blot.. Eplerenone and apocynin inhibited the rise in blood pressure induced by HS and/or aldosterone. This observation was accompanied with a parallel change in kidney protein levels of NADPH oxidase 4 (NOX-4) and p22phox. Aldosterone and high salt were associated with lower NO levels and greater renal oxidative stress.. NADPH oxidase is associated with the vascular and renal remodelling observed in high dietary salt intake. Aldosterone-induced expression of NOX-4 plays a pivotal role in the end-organ damage effect of aldosterone, as eplerenone tended to reduce kidney damage and inhibit NOX expression.

Topics: Acetophenones; Aldosterone; Animals; Blood Pressure; Blotting, Western; Body Weight; Dinoprost; Eplerenone; Male; NADPH Oxidase 4; NADPH Oxidases; Nitric Oxide; Protein Subunits; Proteinuria; Rats; Rats, Inbred Dahl; Sodium; Sodium Chloride, Dietary; Spironolactone; Systole; Urinalysis

We assessed the relative contribution of the mitochondrial respiratory chain and NADPH (nicotinamide adenine dinucleotide phosphate) oxidase to deoxycorticosterone acetate (DOCA)-salt hypertension in mice. The daily mean arterial pressure was monitored by radiotelemetry in DOCA-salt-treated mice given vehicle or the mitochondrial respiratory chain complex I inhibitor rotenone. This treatment produced remarkable attenuation of DOCA-salt hypertension. Similar results were obtained with other inhibitors of mitochondrial function, including 5-hydroxydecanoate (specific for mitochondrial potassium-ATP channels), benzylguanidine (complexes I and III), and the cell-permeable manganese tetrakis (4-benzoic acid) porphyrin (a mimic of mitochondrial superoxide dismutase). In parallel with the blood pressure-lowering effect of rotenone, the DOCA-salt-induced increases in urinary 8-isoprostane excretion and in reactive oxygen species production of isolated kidney mitochondria were both significantly attenuated. Conversely, the DOCA-salt-induced reduction of urinary nitrate/nitrite excretion was significantly elevated. Following DOCA-salt treatment, mice deficient in NADPH oxidase subunits gp91(phox) or p47(phox) exhibited a partial attenuation of the hypertensive response at early but not later time points. Thus, the mitochondrial respiratory chain is a major source of oxidative stress in DOCA-salt hypertension, whereas NADPH oxidase may have a relatively minor role during the early stage of hypertension.

Topics: Acetophenones; Albuminuria; Aldosterone; Animals; Blood Pressure; Cell Line; Desoxycorticosterone; Dinoprost; Electron Transport; Enzyme Inhibitors; Humans; Hypertension; Male; Membrane Glycoproteins; Mice; Mice, Inbred C57BL; Mice, Knockout; Mitochondria; Myocytes, Smooth Muscle; NADPH Oxidase 2; NADPH Oxidases; Nitrogen Oxides; Oxidative Stress; Rotenone; Sodium Chloride

Pathophysiological states, including cardiovascular and renal diseases, are characterized by oxidative stress but what is less clear is whether physiological challenges incur a degree of altered oxidative metabolism. To this end, this study examined whether exposure to a high dietary sodium intake could cause an oxidative stress at the kidney. Animals, placed on either 0.3% or 3% sodium diets for 2 wk, were given a lethal dose of anesthetic, and kidneys were removed to analyze both NAD(P)H oxidase (NOX) and superoxide dismutase (SOD) expression and activities in the cortex and medulla. Placing animals on the high-sodium diet raised sodium and water excretion and caused an approximately 14-fold increase in urinary excretion of 8-isoprostane, a marker of oxidative stress, which was attenuated by chronic treatment with apocynin to prevent NAD(P)H oxidase activity. The protein expression of the NAD(P)H oxidase subunits NOX2 and p47(phox) and overall NAD(P)H oxidase activity were approximately doubled in the cortex of the rats on the high-sodium diet compared with those on the normal sodium intake while both SOD activity and expression were unchanged. By contrast, neither NOX nor SOD protein expression or activity were altered in the medulla when the rats were placed on the high-sodium intake. These data suggest that an elevation in dietary sodium intake can lead to increased generation of reactive oxygen species and a state of oxidative stress in the cortex but not to such a degree that it extends to the medulla.

Topics: Acetophenones; Animals; Biomarkers; Cerebral Cortex; Dinoprost; Kidney; Male; Medulla Oblongata; NADPH Oxidases; Oxidative Stress; Rats; Rats, Wistar; Reactive Oxygen Species; Sodium, Dietary; Superoxide Dismutase

A deficiency in nitric oxide (NO) generation leads to salt-sensitive hypertension, but the role of increased superoxide (O(2)(-)) in such salt sensitivity has not been delineated. We examined the hypothesis that an enhancement in O(2)(-) activity induced by high-salt (HS) intake under deficient NO production contributes to the development of salt-sensitive hypertension. Endothelial NO synthase knockout (eNOS KO; total n = 64) and wild-type (WT; total n = 58) mice were given diets containing either normal (NS; 0.4%) or high-salt (HS; 4%) for 2 wk. During this period, mice were chronically treated with a O(2)(-) scavenger, tempol (400 mg/l), or an inhibitor of NADPH oxidase, apocynin (1 g/l), in drinking water or left untreated (n = 6-8 per group). Blood pressure was measured by radiotelemetry and 24-h urine samples were collected in metabolic cages. Basal mean arterial pressure (MAP) in eNOS KO was higher (125 +/- 4 vs. 106 +/- 3 mmHg) compared with WT. Feeding HS diet did not alter MAP in WT but increased it in eNOS KO to 166 +/- 9 mmHg. Both tempol and apocynin treatment significantly attenuated the MAP response to HS in eNOS KO (134 +/- 3 and 139 +/- 4 mmHg, respectively). Basal urinary 8-isoprostane excretion rates (U(Iso)V), a marker for endogenous O(2)(-) activity, were similar (2.8 +/- 0.2 and 2.4 +/- 0.3 ng/day) in both eNOS KO and WT mice. However, HS increased U(Iso)V more in eNOS KO than in WT (4.6 +/- 0.3 vs. 3.8 +/- 0.2 ng/day); these were significantly attenuated by both tempol and apocynin treatment. These data indicate that an enhancement in O(2)(-) activity contributes substantially to the development of salt-sensitive hypertension under NO-deficient conditions.

Topics: Acetophenones; Animals; Antioxidants; Blood Pressure; Cyclic N-Oxides; Dinoprost; Disease Models, Animal; Hypertension; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Nitric Oxide Synthase Type III; Sodium Chloride, Dietary; Spin Labels; Superoxides

To examine the hypothesis that NAD(P)H oxidase (Nox)-derived superoxide generation is involved in the development of angiotensin II (ANG II)-induced hypertension, we evaluated the responses to ANG II infusion (65 ng/min; osmotic mini-pump) for 2 weeks in rats treated with or without apocynin (APO) (inhibitor of Nox subunits assembly) in drinking water (12 mmol/L). Rats were grouped according to their diets with varying salt content (normal salt [NS], 0.4%; high salt [HS], 8%; low salt [LS], 0.03%) given during the 2-week experimental period. The variation in salt intake did not alter mean arterial pressure (MAP, recorded via pre-implanted arterial catheter) but showed proportionate levels in urinary excretion rate of Isoprostaglandin(2alpha) (U(ISO)V; NS, 179 +/- 26; HS, 294 +/- 38; LS, 125 +/- 7 ng/kg/24 h). Treatment with ANG II increased MAP proportional to salt intake (NS, 126 +/- 3 to 160 +/- 5; HS, 116 +/- 4 to 184 +/- 5; LS, 125 +/- 1 to 154 +/- 5 mm Hg). However, ANG II increased U(ISO)V only in NS rats (250 +/- 19 ng/kg/24 h) but not in HS or LS rats. In response to ANG II, Nox subunits protein expression increased in HS but not in the NS or LS rats. Apocynin treatment partially ameliorated these changes in Nox proteins in HS rats but did not alter ANG II-induced increases in MAP or U(ISO)V. These data suggest that Nox activation may not be the sole factor or alternatively, that a constitutively active isoform of Nox is involved in oxidative stress mechanism that is associated with dietary salt or ANG II-induced hypertension.

Topics: Acetophenones; Angiotensin II; Animals; Blood Pressure; Blotting, Western; Diet, Sodium-Restricted; Dinoprost; Disease Models, Animal; Enzyme Inhibitors; Hypertension; Infusions, Intravenous; Male; Oxidative Stress; Rats; Rats, Sprague-Dawley; Thiobarbituric Acid Reactive Substances; Vasoconstrictor Agents

We studied the relationship among endothelial function, oxidative stress, and phenylephrine (PE; alpha(1)-adrenoceptor agonist)-induced contraction in mesenteric arteries from high-cholesterol (HC)-diet-fed mice. In HC mice (vs age-matched normal-diet-fed mice): (1) PE-induced contraction in endothelium-intact rings was enhanced (endothelial denudation increased contraction in "normal-diet" rings, but did not enhance it further in "HC" rings); (2) the enhanced PE-induced contraction was further enhanced in the presence of N(G)-nitro-L-arginine (L-NNA; nitric oxide synthase inhibitor) or L-NNA plus indomethacin (cyclooxygenase inhibitor) [to preserve endothelium-derived hyperpolarizing factor (EDHF)], but unchanged in the presence of charybdotoxin plus apamin (to block EDHF); (3) ACh-induced EDHF-type relaxation was reduced; and (4) oxidative stress [indicated by the plasma 8-isoprostane level (reliable systemic marker) and aortic superoxide production] was greater. In HC mice, PE-induced contraction was normalized by apocynin [NAD(P)H oxidase inhibitor] or tempol (superoxide dismutase mimetic), but enhanced by NADH [NAD(P)H oxidase substrate]. Oral dietary supplementation with apocynin (30 mg/kg/day for 4 weeks) corrected the above abnormalities. Hence: (1) PE-induced contraction is modulated by the endothelium, and the enhanced contractility in HC mice results from defective EDHF signaling and elevated oxidative stress, and (2) apocynin normalizes PE-induced contraction in HC mice by improving EDHF signaling.

Topics: Acetophenones; Acetylcholine; Adrenergic alpha-Agonists; Animals; Biological Factors; Cholesterol, Dietary; Dinoprost; Endothelium, Vascular; Enzyme Inhibitors; Hypercholesterolemia; Male; Mesenteric Arteries; Mice; Mice, Inbred ICR; NADPH Oxidases; Nitric Oxide Synthase Type II; Nitric Oxide Synthase Type III; Nitroprusside; Oxidative Stress; Phenylephrine; Potassium; Signal Transduction; Superoxides; Vasoconstriction