Pelargonidin Protects Against Renal Injury in a Mouse Model of Sepsis.

Pelargonidin (PEL) is a well-known red pigment found in plants, and it has been reported to have important biological activities that are potentially beneficial for human health. This study was initiated to determine whether PEL could modulate renal functional damage in a mouse model of sepsis, and to elucidate the underlying mechanisms. The potential of PEL treatment to reduce renal damage induced by cecal ligation and puncture (CLP) surgery in mice was measured by assessment of serum creatinine, blood urea nitrogen (BUN), lipid peroxidation, total glutathione, glutathione peroxidase (GSH-Px) activity, catalase activity, and superoxide dismutase (SOD) activity. Treatment with PEL resulted in elevated plasma levels of BUN and creatinine, and of protein in urine in mice with CLP-induced renal damage. Moreover, PEL inhibited nuclear factor-κB activation and reduced the induction of nitric oxide synthase and excessive production of nitric acid. PEL treatment also reduced the plasma levels of interleukin-6 and tumor necrosis factor-α reduced lethality due to CLP-induced sepsis, increased lipid peroxidation, and markedly enhanced the antioxidant defense system by restoring the levels of SOD, GSH-Px, and catalase in kidney tissues. These results suggested that PEL protects mice against sepsis-triggered renal injury.

Steroidogenic Acute Regulatory Protein (StAR) Overexpression Reduces Inflammation and Insulin Resistance in Obese Mice.

Steroidogenic acute regulatory protein (StAR), a mitochondrial cholesterol delivery protein, plays a beneficial role in hyperlipidemia, NAFLD, and endothelial inflammation. Elevated circulating fatty acids and low grade inflammation are known as key risk factors of insulin resistance and type 2 diabetes. In the present study, C57BL/6J mice were fed with HFD and infected with recombinant adenovirus expressing StAR by tail-vein injection. Intraperitoneal glucose/insulin tolerance test was performed to assess the insulin sensitivity. Morphological analysis and intramuscular lipid determination were used to illustrate the adipose hypertrophy and ectopic fat accumulation in skeletal muscle. The levels of inflammatory factor and nitric oxide were determined by ELISA and classic Griess reagent methods, respectively. The fatty acids composition was analysis using gas chromatography-mass spectrometry (GC-MS). The expression of genes associated with inflammation and insulin resistance were determined by Western blotting and qPCR to elucidate the underlying mechanism. We demonstrated that StAR overexpression ameliorated insulin resistance and systemic inflammatory response with the reduction of adipose hypertrophy and intramuscular lipid in HFD-fed mice. In addition, StAR overexpression increased serum unsaturated fatty acids (UFAs) and PPARγ expression in muscle and adipose tissue of obese mice. In conclusion, StAR may activate PPARγ by increasing UFAs, which leads to a protective role in systemic inflammation and insulin resistance in obese mice. J. Cell. Biochem. 118: 3932-3942, 2017. © 2017 Wiley Periodicals, Inc.

Oxidative stress and lowered total antioxidant status are associated with a history of suicide attempts.

BACKGROUND: There is evidence that depression is accompanied by inflammation, oxidative and nitrosative stress (O&NS) and metabolic disorders. However links between oxidative stress and suicide attempts in depressed patients are poorly understood. This study examines whether a history of suicide attempts is associated with inflammation, O&NS and metabolic disorders. METHODS: Blood specimens were collected from study participants aged 18-60 (N=342) recruited at the State University of Londrina, Brazil, and measured for oxidative stress biomarkers: nitric oxide metabolites (NOx), lipid hydroperoxides, malondialdehyde, advanced oxidation protein products and plasma total antioxidant potential (TRAP); inflammatory biomarkers: fibrinogen, high-sensitivity C-reactive protein, erythrocyte sedimentation rate, interleukin-6 and tumor necrosis factor-α; and metabolic variables. Subjects were divided into those with (n=141) and without (n=201) a history of suicidal attempts. RESULTS: Individuals with a history of suicide attempts had significantly higher levels of NOx and lipid hydroperoxides and lowered TRAP as compared to individuals without suicide attempts. There were no significant associations between a history of suicide attempts and inflammatory and metabolic biomarkers and metabolic syndrome. Logistic regression showed that both unipolar and bipolar disorder, female gender, smoking behavior and lipid hydroperoxides were significantly associated with a history of suicide attempts. The combined effects of oxidative stress, smoking, depression, female gender were independent from classical risk factors, including marital status, years of education and anxiety. CONCLUSIONS: O&NS as well as lowered antioxidant levels may play a role in the pathophysiology of suicidal behavior independently from the effects of depression and smoking, both of which are associated with increased O&NS, and classical suicide predictors, such as years of education and marital status.

[Erythrocytes and microvascular tone during acute traumatic haemorrhagic shock]. / Érythrocytes et tonus microvasculaire au cours du choc hémorragique traumatique.

Haemorrhagic shock remains a leading cause of death in trauma patients. The concept of haematologic damage control is gradually taking place in the management of traumatic haemorrhagic shock. It is based primarily on the early implementation of a quality blood transfusion involving erythrocytes, plasmas and platelets transfusion. Red blood cell transfusion is mainly supported by the oxygen carrier properties of erythrocytes. However, it appears that erythrocytes ability to modulate the bioavailability of nitric oxide (NO) plays a major role in capillary opening and perfusion. Erythrocytes are also actively involved in the processes of hemostasis and coagulation. In this context, it seems difficult to define a threshold of hemoglobin concentration to determine the implementation of a blood transfusion in traumatic haemorrhagic shock.

Insulin suppresses endotoxin-induced oxidative, nitrosative, and inflammatory stress in humans.

OBJECTIVE: To investigate whether insulin reduces the magnitude of oxidative, nitrosative, and inflammatory stress and tissue damage responses induced by endotoxin (lipopolysaccharide [LPS]). RESEARCH DESIGN AND METHODS: Nine normal subjects were injected intravenously with 2 ng/kg LPS prepared from Escherichia coli. Ten others were infused with insulin (2 units/h) for 6 h in addition to the LPS injection along with 100 ml/h of 5% dextrose to maintain normoglycemia. RESULTS: LPS injection induced a rapid increase in plasma concentrations of nitric oxide metabolites, nitrite and nitrate (NOM), and thiobarbituric acid-reacting substances (TBARS), an increase in reactive oxygen species (ROS) generation by polymorphonuclear leukocytes (PMNLs), and marked increases in plasma free fatty acids, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), monocyte chemoattractant protein-1 (MCP-1), macrophage migration inhibition factor (MIF), C-reactive protein, resistin, visfatin, lipopolysaccharide binding protein (LBP), high mobility group-B1 (HMG-B1), and myoglobin concentrations. The coinfusion of insulin led to a total elimination of the increase in NOM, free fatty acids, and TBARS and a significant reduction in ROS generation by PMNLs and plasma MIF, visfatin, and myoglobin concentrations. Insulin did not affect TNF-α, MCP-1, IL-6, LBP, resistin, and HMG-B1 increases induced by the LPS. CONCLUSIONS: Insulin reduces significantly several key mediators of oxidative, nitrosative, and inflammatory stress and tissue damage induced by LPS. These effects of insulin require further investigation for its potential use as anti-inflammatory therapy for endotoxemia.

Relationship between endogenous concentrations of vasoactive substances and measures of peripheral vasodilator function in patients with coronary artery disease.

1. The aim of the present study was to determine the relationship between plasma concentrations of nitrite/nitrate (NO(x)) and endothelin (ET)-1 and non-invasive measures of peripheral vasodilator function in patients with coronary artery disease (CAD). 2. Twenty-two patients with angiographic CAD underwent non-invasive measurement of peripheral vasodilator function in the brachial conduit artery (flow-mediated dilation (FMD) testing via ultrasound) and in the forearm resistance arteries (via venous occlusion plethysmography) during reactive hyperaemia after 5 min ischaemia. In addition, plasma NO(x) and ET-1 concentrations were determined. 3. The plasma concentration of NO(x) was related to the peak brachial FMD response when expressed as either the relative (%) or absolute (mm) change in diameter (r = 0.73, P < 0.001; and r = 0.64, P < 0.01, respectively). Moreover, plasma concentrations of NO(x) demonstrated a relationship with forearm vasodilation estimated by total forearm blood flow following 5 min ischaemia (r = 0.63, P < 0.01) and the flow debt repayment of the forearm (r = 0.54, P < 0.01). Finally, ET-1 concentrations were inversely related to FMD% (r = -0.45, P < 0.05). 4. The findings of the present study demonstrate a relationship between the plasma concentrations of NO(x) and measures of vascular reactivity in conduit and resistance arteries in patients with CAD. Therefore, measurement of plasma NO(x) may serve as a reliable marker for peripheral vasodilator dysfunction in patients with CAD.

Oxidative and nitrosative stress in acute ischaemic stroke.

BACKGROUND: Increased nitric oxide (NO) production may result in further brain damage via nitric oxide synthase uncoupling in patients with acute ischaemic stroke by increasing free radical formation and oxidative stress. In this connection, we measured nitrite and nitrate (NO metabolites), ischaemia-modified albumin (IMA) and thiobarbituric acid-reactive substances (TBARS) in patients with ischaemic stroke. METHODS: We studied 41 patients with ischaemic stroke (22 men and 19 women, aged 65+/-13 years) and 37 age- and sex-matched controls (22 men and 15 women, aged 65+/-8 years). Blood samples were drawn within the first 24 h from the onset of symptoms in the patient group. Fasting morning samples were used in the control group. Concentrations of nitrite and nitrate were determined by Griess reagent; concentrations of IMA were determined by the albumin cobalt-binding test; and concentrations of TBARS were determined colorimetrically by thiobarbituric acid. RESULTS: Nitrate, IMA and TBARS concentrations were significantly increased compared with controls (P<0.005, P<0.001, and P=0.01, respectively). CONCLUSIONS: Patients with acute ischaemic stroke exhibit abnormalities in a range of markers of increased nitrosative and oxidative stress. These abnormalities may contribute to greater brain damage in patients with acute ischaemic stress.

Phase II study of pomegranate juice for men with rising prostate-specific antigen following surgery or radiation for prostate cancer.

PURPOSE: Phytochemicals in plants may have cancer preventive benefits through antioxidation and via gene-nutrient interactions. We sought to determine the effects of pomegranate juice (a major source of antioxidants) consumption on prostate-specific antigen (PSA) progression in men with a rising PSA following primary therapy. EXPERIMENTAL DESIGN: A phase II, Simon two-stage clinical trial for men with rising PSA after surgery or radiotherapy was conducted. Eligible patients had a detectable PSA > 0.2 and < 5 ng/mL and Gleason score < or = 7. Patients were treated with 8 ounces of pomegranate juice daily (Wonderful variety, 570 mg total polyphenol gallic acid equivalents) until disease progression. Clinical end points included safety and effect on serum PSA, serum-induced proliferation and apoptosis of LNCaP cells, serum lipid peroxidation, and serum nitric oxide levels. RESULTS: The study was fully accrued after efficacy criteria were met. There were no serious adverse events reported and the treatment was well tolerated. Mean PSA doubling time significantly increased with treatment from a mean of 15 months at baseline to 54 months posttreatment (P < 0.001). In vitro assays comparing pretreatment and posttreatment patient serum on the growth of LNCaP showed a 12% decrease in cell proliferation and a 17% increase in apoptosis (P = 0.0048 and 0.0004, respectively), a 23% increase in serum nitric oxide (P = 0.0085), and significant (P < 0.02) reductions in oxidative state and sensitivity to oxidation of serum lipids after versus before pomegranate juice consumption. CONCLUSIONS: We report the first clinical trial of pomegranate juice in patients with prostate cancer. The statistically significant prolongation of PSA doubling time, coupled with corresponding laboratory effects on prostate cancer in vitro cell proliferation and apoptosis as well as oxidative stress, warrant further testing in a placebo-controlled study.

[Protective effects of San Baoxin on injury induced by myocardical ischemic reperfusion and anti-thrombosis in rats].

OBJECTIVE: To investigate the effects of San Baoxin on myocardial injury induced by ischemia-reperfusion (MI/R) and thrombogenesis in rats in vivo and ex vivo. METHOD: The experimental model was established by ligation of left anterior descending coronary artery for 30 min followed by reperfusion for 180 min. The Chandler method was used to produced ex vivo thrombosis and an electrical stimulation of common carotid artery was adopted to form in vivo thrombosis respectively, the effect of antithrombosis induced by San Baoxin was observed. RESULT: San Baoxin significantly decreased the content of malondialdehyde (MDA), obviously elevated the activity of superoxide dismutase (SOD) and increased the amount of NO of the serum simultaneously. The San Baoxin at the dosage of 10 g x kg(-1) could remarkably lengthen the OT ( P < 0.05). All San Baoxin dosages could inhibit the formation of ex vivo thrombosis. CONCLUSION: San Baoxin protects the myocardium from injury of ischemic and reperfusion. The protective effect of San Baoxin may be due to that it can dilate vessels, increase the activity of clearance enzyme of free radical and inhibit lipid peroxidation and the formation of ex vivo and in vivo thrombosis.

Nitric oxide and cellular immunity in experimental cutaneous leishmaniasis.

We examined the local and systemic production of nitric oxide (NO) and the pattern of cytokine during the course of Leishmania mexicana infection in susceptible BALB/c and resistant C57BL/6 mice. NO derivatives were measured in serum, and the expression of inducible nitric oxide synthase (iNOS), interferon (IFN-gamma), interleukin (IL-4) and epidermal Langerhans cells (LC) was measured in the lesions by immunohistology. Circulating NO concentrations, iNOS+ cell density, IFN-gamma+ Th1 cells and CD205+ Langerhans cells were higher in early lesions of resistant C57BL/6 mice. In contrast, susceptible BALB/c mice developed chronic and progressive lesions with a predominance of IL-4+ Th2 cells. In both susceptible and resistant mice, lesion size and lymph node volume followed a similar course. The early local and systemic production of NO in resistant mice may be related with the premature production of IFN-gamma observed, contributing to the resolution of the lesion.

[Effects of hemodialysis with different membranes on blood serum nitrite/nitrate concentrations]. / Wplyw zabiegu hemodializy z uzyciem róznych blon dializacyjnych na stezenia azotynów/azotanów w surowicy krwi.

Blood serum nitrite/nitrate concentrations were determined in 10 patients with chronic uraemia during 4-hour hemodialysis (HD). Cuprophane, polysulphone and polyacrylnitrile dialysis membranes were used during HD procedures. Blood serum concentrations of nitrite/nitrate were increased in HD patients prior to hemodialysis as compared with respective values in healthy subjects. During hemodialysis, regardless of the membrane type used, blood serum nitrite/nitrate concentrations were progressively decreasing as compared with initial values found before hemodialysis. The lowest decrease of blood serum nitrite/nitrate concentrations was found during HD with cuprophane membrane.

Nitric oxide concentrations are increased in the feto-placental circulation in intrauterine growth restriction.

The aim of this study was to measure plasma concentrations of total nitrites, as an index of nitric oxide (NO) synthesis, in the fetal circulation of normal pregnancies and in pregnancies complicated by intrauterine growth restriction. Plasma was prepared from umbilical venous blood collected from 13 placentae from normal pregnancies complicated by intrauterine growth restriction. Plasma NO concentrations were determined using the Greiss reaction by measuring combined oxidation products of NO, plasma nitrite (NO2-) and nitrate (NO3-) after reduction with nitrate reductase. Significantly higher NO2-concentrations were found in umbilical venous plasma in the group complicated by intrauterine growth restriction compared to the control group (65.6 mumol/1, P < 0.001. These results support the hypothesis that increased NO production may be a compensatory response to improve blood flow in the placenta and/or may play a role in limiting platelet adhesion and aggregation.

Effects of L-arginine on utero-placental circulation in growth-retarded fetuses.

BACKGROUND: To evaluate the effects of L-arginine (ARG) infusion, the nitric oxide as substrate, on the utero-placental circulation at third trimester. METHODS: Three groups of nine pregnant women each were infused i.v. with 30 g ARG, for 30 minutes. One group served as control, and the two remnants were composed by patients with intrauterine growth retardation with (IUGR-B) or without (IUGR-A) increased resistances in the utero-placental circulation. Changes of blood flow velocity waveforms of both uterine arteries and umbilical artery were recorded for 60 minutes. Blood pressure, serum nitrites/nitrates and growth hormone levels were also measured. RESULTS: No hemodynamic changes in utero-umbilical circulation were observed during infusion in any of the three groups. Considering the uterine arteries separately as placental and non-placental sided we found a significant decrease of non-placental side resistances in IUGR-B women. Indeed, the pulsatility index was lowered by 14%, in respect of baseline value. Serum nitrites/nitrates as well as serum growth hormone levels were significantly increased by ARG, in every woman, irrespective of the presence of fetal growth retardation. Blood pressure remained unaffected during infusion in every woman. CONCLUSIONS: These findings suggest that L-arginine infusion affects utero-placental circulation in patients with IUGR associated with increased uterine resistances. Such an action is specific and appears possibly to be mediated by a release of nitric oxide.

Plasma nitrate concentrations in neutropenic and non-neutropenic patients with suspected septicaemia.

Nitric oxide (NO) is an important physiological mediator of vascular tone and is thought to be involved in the pathogenesis of septic shock. Plasma nitrate is the stable end product of NO oxidation and in part reflects endogenous NO production. We measured plasma nitrate levels in 47 episodes of suspected septicaemia in 43 in-patients (16 male and 27 female, age 15-63 years). Nitrate concentrations were significantly higher (P < 0.01) compared to healthy controls. Further analysis revealed that significantly elevated levels occurred only in the septic patients who had normal or elevated numbers of neutrophils in the peripheral blood and were hypotensive on presentation. Failure of plasma nitrate concentrations to rise significantly in patients with neutropenia suggests that this cell type may be important in the activation of the arginine-NO system in severe sepsis in man.

Monophosphoryl lipid A as a prophylactic for sepsis and septic shock.

The ability of monophosphoryl lipid A (MLA) to provide prophylactic protection against septic shock was evaluated in a mouse model of induced endotoxin hypersensitivity. Treatments of hypersensitized animals with low doses of MLA attenuated endotoxin lethality and endotoxin-mediated liver damage. These effects were related to the ability of MLA to suppress accumulation of TNF-alpha and IFN-gamma in the bloodstream of animals. MLA treatments had only a modest effect in suppressing the accumulation of nitrate in the bloodstream. This implied that MLA did not suppress induction of macrophage and hepatocyte nitric oxide synthetases that contribute to antimicrobial defense and protect against endotoxin-mediated liver damage. The MLA treatments did not appear to compromise inflammatory defenses against local infection since locally recruited leukocytes remained responsive to endotoxin after hypersensitivity had been attenuated. In agreement with these findings, other studies have shown that the induction of endotoxin tolerance by MLA parallels the induction of resistance of animals to lethal challenges with either Gram negative or Gram positive bacteria. As predicted from preclinical studies, human trials of the clinical form of MLA (MPL-immunostimulant) have confirmed that MLA could attenuate systemic responses to endotoxin in normal volunteers, including the attenuation of blood cytokine accumulation and attenuation of symptomatic responses.

Renal regulation of acid-base equilibrium during chronic administration of mineral acid.

Previous studies in metabolic alkalosis have demonstrated that two factors are the prime determinants of acid excretion and bicarbonate reabsorption; first, the diversion to distal exchange sites of sodium previously reabsorbed in the proximal tubule and loop of Henle; and, second, a stimulus to sodium-cation exchange greater than that produced by a low-salt diet alone. In the present study we have examined the hypothesis that these two factors are also the prime determinants of acid excretion during the administration of mineral acid loads. To test this hypothesis, we have administered to dogs ingesting a low NaCl diet a daily dose of 7 meq/kg of H+ with anions (chloride, sulfate, or nitrate) whose differing degrees of reabsorbability influence the speed and completeness with which each is delivered to the distal nephron with its accompanying Na+. After 2-3 wk of acid administration, and after an initial urinary loss of Na+ and K+, the steady-state value for plasma [HCO3-] was 8.6 meq/liter below control in the HCl group, 3.7 meq/liter below control in the H2SO4 group, and unchanged from control in the HNO3 group; all of these values were significantly different from each other. We would propose the following explanation for our findings: when HCl is administered chronically, marked acidosis occurs because distal delivery of Cl- is restricted by the ease with which the Cl- can be reabsorbed in the proximal portions of the nephron. Only when Cl- retention produces sufficient hyperchloremia to insure delivery of Na+ (previously reabsorbed in proximal tubule and loop of Henle) to the distal nephron in quantities equal to ingested Cl is this primary constraint removed. In the case of sulfuric and nitric acids, there is no constraint on distal delivery, the nonreabsorbability of the administered anion causing prompt, total delivery of Na+ to exchange sites in quantities equal to administered hydrogen. Thus, with H2SO4 and HNO3 the sole constraint on removal of the acid load is the inability of the distal exchange mechanism to conserve the Na+ increment fully by means of H+ exchange. Escape of Na+ and K+ into the urine and the resulting stimulus to Na(+)-H+ exchange remove this constraint and are responsible for establishment of a new steady-state of acid-base equilibrium at plasma [HCO3-] levels significantly higher than those seen with HCl. The feeding of HCl in the presence of a normal salt intake led to a degree of metabolic acidosis not significantly different from that seen in dogs ingesting a low-salt diet. We suggest that the presence of dietary sodium at distal exchange sites did not enhance acid excretion because it is only after a loss of body sodium stores that sodium avidity is increased sufficiently to allow full removal of the acid load. The present findings indicate that the fundamental factors controlling acid excretion and bicarbonate reabsorption in metabolic acidosis are closely similar to those operative in metabolic alkalosis.