Immune cell inflammatory cytokine responses differ between central and systemic compartments in response to acute exercise in mice

BACKGROUND

Exhaustive exercise induces apoptosis and oxidative stress in systemic organs and tissues and is associated with increased levels of pro-inflammatory cytokines. The effects of acute exercise on cytokine expression and apoptosis of immune cells in the central nervous system (CNS) have not been well characterized.

PURPOSE

We investigated the effects of a single bout of strenuous exercise on the expression of TNF-alpha, IL-6, and IL-beta, as well as the apoptotic status of cells in the hippocampus of healthy mice. To compare central vs. systemic differences, cytokine expression in the intestinal lymphocytes of a subset of mice were also assessed.

METHODS

Female C57BL/6 mice were divided into three groups: sedentary controls (NOTREAD) (n = 22), treadmill exercise with immediate sacrifice (TREAD-Imm) (n = 21), or treadmill exercise with sacrifice after 2 hours (TREAD-2h). TNF-alpha, IL-6, and IL-1beta expression in the hippocampus and intestinal lymphocytes were measured by Western blot analysis. Percentages of hippocampal cells undergoing apoptosis (Annexin+) or necrosis (Propidium Iodide+) were determined through flow cytometry. Plasma levels of 8-isoprostane and corticosterone were measured using commercially available EIA kits.

RESULTS

Acute treadmill exercise led to significant decreases in TNF-alpha (p<0.05) and increases in IL-6 (p<0.05) expression in the hippocampus of healthy mice. No effects of acute exercise on the apoptotic status of hippocampal cells were observed. In intestinal lymphocytes, the exercise bout led to significant increases in TNF-alpha (p<0.05), IL-6 (p<0.05), and IL-1beta (p<0.05). Acute exercise was associated with a significant increase in both plasma 8-isoprostane (p<0.05) and corticosterone (p<0.05) levels.

CONCLUSION

Acute exercise differentially affects the pattern ofpro-inflammatory cytokine expression in the hippocampus compared to intestinal lymphocytes and, further, does not induce apoptosis in hippocampal cells.

Impact of different welding techniques on biological effect markers in exhaled breath condensate of 58 mild steel welders

Total mass and composition of welding fumes are predominantly dependent on the welding technique and welding wire applied. The objective of this study was to investigate the impact of welding techniques on biological effect markers in exhaled breath condensate (EBC) of 58 healthy welders. The welding techniques applied were gas metal arc welding with solid wire (GMAW) (n=29) or flux cored wire (FCAW) (n=29). Welding fume particles were collected with personal samplers in the breathing zone inside the helmets. Levels of leukotriene B(4) (LTB(4)), prostaglandin E(2) (PGE(2)), and 8-isoprostane (8-iso-PGF(2α)) were measured with immunoassay kits and the EBC pH was measured after deaeration. Significantly higher 8-iso-PGF(2α) concentrations and a less acid pH were detected in EBC of welders using the FCAW than in EBC of welders using the GMAW technique. The lowest LTB(4) concentrations were measured in nonsmoking welders applying a solid wire. No significant influences were found in EBC concentrations of PGE(2) based upon smoking status or type of welding technique. This study suggests an enhanced irritative effect in the lower airways of mild steel welders due to the application of FCAW compared to GMAW, most likely associated with a higher emission of welding fumes.

Protective effect of Shenfu injection on thromboangiitis obliterans model rats

ETHNOPHARMACOLOGICAL RELEVANCE

Thromboangiitis obliterans (TAO) or Buerger's disease is a non atherosclerotic, segmentar inflammatory vasculitis that is incurable at present. Shenfu injection (SFI), a traditional Chinese formulation, have been confirmed to produce protective influences on several organs and limb during ischemia and reperfusion (IR) injury in rats. However, the effects of SFI on TAO remain unclear.

MATERIALS AND METHODS

Adult male Sprague Dawley rats were randomly divided into sham operated group, TAO model group, SFI 2.5mg/kg (low dose), 5mg/kg (medium dose) and 10mg/kg (high dose) groups (n=8). Rats were intravenously administered SFI 2.5, 5 and 10mg/kg or saline once per day for 15 days. TAO model was prepared by injecting sodium laurate into the femoral artery of rats. Then we examined the changes of pathological signs, pathologic grading of thrombus, the indexes of hematology, the contents of thromboxane B2 (TXB2), 6-keto-prostaglandin F(lα) (6-K-PGF(1α)) in plasma following SFI or saline treatment.

RESULTS

More pathological signs of lesions, higher grades of pathological thrombosis, increased blood platelet counts, the increase in the TXB2 and TXB2/6-K-PGF(1α) ratio, as well as the decrease of 6-K-PGF(1α) in TAO model group were shown in present experiments; SFI treatment significantly improved the pathological signs of lesions induced by sodium laurate injection, reduced the numbers of thrombus formation, blood platelet counts, the TXB2 and TXB2/6-K-PGF(1α) ratio but increased the 6-K-PGF(1α) compared with TAO model group. However, there were no significant alterations in the counts of red blood cell, leucocyte and neutrophil among these groups.

CONCLUSIONS

Our preliminary findings first indicated that SFI can produce significant therapeutic effects on experimental Buerger's disease model rats in a dose independent manner. The underlying mechanisms may be due to its modifying hematology, inhibiting platelet aggregation and enhancing anti-thrombotic function of vessel endothelia.

Luteolysis and associated interrelationships among circulating PGF2α, progesterone, LH, and estradiol in mares

The changing concentrations and temporal relationships among a PGF2α metabolite (PGFM), progesterone (P(4)), LH, and estradiol-17β (E(2)) before, during, and after luteolysis were studied in 10 mares. Blood samples were collected every hour for ≥4 d beginning on day 12 after ovulation. The luteolytic period extended from a decrease in P(4) at a common transitional hour (Hour 0) at the end of preluteolysis and beginning of luteolysis to a defined ending when P(4) reached 1 ng/mL. The length of luteolysis was 22.9 ± 0.9 h, contrasting with 2 d in published P(4) profiles from sampling every 6 to 24 h. In mares with complete data for Hours -40 to -2 (n = 6), PGFM concentrations remained below assay sensitivity (n = 2) or two or three small pulses (peak, 29 ± 4 pg/mL) occurred. During luteolysis, the pulses became more prominent (peak, 193 ± 36 pg/mL). Rhythmicity of PGFM pulses was not detected by a pulsatility program during preluteolysis but was detected in seven of nine mares during luteolysis and postluteolysis combined. The nadir-to-nadir interval for LH pulses and the peak-to-peak interval between adjacent pulses were longer (P < 0.05) during preluteolysis than during luteolysis (nadir to nadir, 5.2 ± 0.3 h vs 3.6 ± 0.4 h; peak to peak, 9.4 ± 1.0 h vs 4.7 ± 0.5 h). Unlike reported findings in cattle, concentrations of P(4) decreased linearly within the hours of each PGFM pulse during luteolysis, and a positive effect of an LH pulse on P(4) and E(2) concentration was not detected. The reported balancing of P(4) concentrations between a negative effect of PGF2α and a positive effect of LH in heifers was not detected in mares.

Pretreatment with n-6 PUFA protects against subsequent high fat diet induced atherosclerosis--potential role of oxidative stress-induced antioxidant defense

OBJECTIVES

Recent evidence suggests that oxidative stress can promote antioxidant defense and thus be athero-protective. n-6 polyunsaturated fatty acids (n-6 PUFA) are more prone to oxidation, compared to monounsaturated fatty acids (MUFA) and yet have proven anti-atherosclerotic effects. In this study, we tested whether early exposure to a diet rich in n-6 PUFA, compared to a MUFA rich diet would reduce lesion burden, even with subsequent exposure to a high fat, high cholesterol diet (HF). Further, we tested to determine whether oxidative mechanisms are involved in such protection.

METHODS AND RESULTS

Twenty four, 4 week old, male, LDL receptor knockout (LDL-R(-/-)) mice were divided into two groups and fed either a n-6 PUFA rich or a MUFA rich diet for a period of 12 weeks. At this point, 4 mice from each group were euthanized and the remaining 8 mice from each group were fed a HF diet for four weeks. Atherosclerotic lesions, plasma lipids, autoantibodies to lipid peroxide modified proteins, isoprostanes and aortic catalase levels were measured. The n-6 PUFA diet reduced aortic lesions and plasma lipids compared to the MUFA diet and this reduction in lesions continued even after the mice were switched over to the HF diet, despite the fact that the plasma lipids were similar in both groups after the HF diet. n-6 PUFA fed mice had highest plasma isoprostane levels, indicating oxidative stress, but also had higher levels of aortic catalase. On the other hand, MUFA fed mice had comparatively lower levels of isoprostanes and their aortic catalase levels remained low. Finally, aortic lesions were negatively correlated with isoprostanes and catalase.

CONCLUSION

An initial exposure to a n-6 PUFA rich diet compared to a MUFA rich diet reduces atherosclerotic lesions and this protection probably involves oxidative stress induced by PUFA.

Reduction of 8-iso-prostaglandin F2α in the first week after Roux-en-Y gastric bypass surgery

Obesity is associated with increased markers of oxidative stress. We examined whether oxidative stress is reduced within the first week after Roux-en-Y gastric bypass (RYGB) surgery and could be related to changes in adipose tissue depots. The reactive oxygen species (ROS) marker 8-iso-prostaglandin F2α (8-iso-PGF2α) and activity of antioxidant glutathione peroxidases (GPX) in plasma were compared before and ~1 week after RYGB. The effects of RYGB on subcutaneous adipose tissue and interstitial fluid 8-iso-PGF2α levels and subcutaneous adipose tissue expression of GPX-3 were also assessed. Levels of 8-iso-PGF2α in subcutaneous and visceral adipose tissue were determined. Plasma 8-iso-PGF2α levels decreased (122 ± 75 to 56 ± 15 pg/ml, P = 0.001) and GPX activity increased (84 ± 18 to 108 ± 25 nmol/min/ml, P = 0.003) in the first week post-RYGB. RYGB also resulted in reductions of 8-iso-PGF2α in subcutaneous adipose tissue (1,742 ± 931 to 1,132 ± 420 pg/g fat, P = 0.046) and interstitial fluid (348 ± 118 to 221 ± 83 pg/ml, P = 0.046) that were comparable to plasma (26-33%, P = 0.74). Adipose GPX-3 expression was increased (6.7 ± 4.7-fold, P = 0.004) in the first postoperative week. The improvements in oxidative stress occurred with minimal weight loss (2.4 ± 3.4%, P = 0.031) and elevations in plasma interleukin-6 (18.0 ± 46.8 to 28.0 ± 58.9 pg/ml, P = 0.004). Subcutaneous and visceral adipose tissues express comparable 8-iso-PGF2α levels (1,204 ± 470 and 1,331 ± 264 pg/g fat, respectively; P = 0.34). These data suggest that RYGB affects adipose tissue leading to the restoration of adipose redox balance within the first postoperative week and that plasma 8-iso-PGF2α is primarily derived from subcutaneous adipose tissue.

Effect of dose of estradiol-17β on prominence of an induced 13,14-dihydro-15-keto-PGF(2α) (PGFM) pulse and relationship of prominence to progesterone, LH, and luteal blood flow in heifers

Various doses of estradiol-17β (E(2)) were used in heifers to induce a pulse of 13,14-dihydro-15-keto-prostaglandin F(2α) (PGFM). The effect of E(2) concentration on the prominence of PGFM pulses and the relationship between prominence and intrapulse concentration of progesterone (P(4)), LH, and luteal blood flow were studied. A single dose of 0 (vehicle), 0.01, 0.05, or 0.1 mg of E(2) was given (n = six/group) 14 d after ovulation. Blood samples were collected, and luteal blood flow was evaluated hourly for 10 h after the treatment. The 0.05-mg dose increased and the 0.1-mg dose further increased the prominence of the induced PGFM pulse, compared with the 0.0-mg dose and the 0.01-mg dose. The PGFM pulses were subdivided into three different prominence categories (<50, 50 to 150, and >150 pg/mL at the peak). In the 50 to 150 category, P(4) concentration increased (P < 0.05) between -2 h and 0 h (0 h = peak of PGFM pulse). In the >150 category, P(4) decreased (P < 0.05) between -1 h and 0 h, LH increased (P < 0.05) at 1 h, and luteal blood flow apparently decreased (P < 0.05) at 2 h of the PGFM pulse. The novel results supported the following hypotheses: (1) an increase in E(2) concentration increases the prominence of a PGFM pulse, and (2) greater prominence of a PGFM pulse is associated with a greater transient intrapulse depression of P(4) at the peak of the PGFM pulse. In addition, the extent of the effect of prostaglandin F(2α) on the increase in LH and changes in blood flow within the hours of a PGFM pulse was related positively to the prominence of the PGFM pulse.

[Effect on PGF2alpha in plasma in primary dysmenorrhea treated with eye acupuncture]

OBJECTIVE

To observe the clinical curative effect of primary dysmenorrhea and the content of prostaglandin F2alpha (PGF2alpha) in peripheral blood of menstrual periods treated with eye acupuncture therapy.

METHODS

One hundred and ten cases of primary dysmenorrhea were randomly divided into an eye acupuncture group (60 cases) and a medication group (50 cases). In eye acupuncture group, low energizer area, liver area, kidney area, heart area and spleen area etc. were selected according to the differentiation, and the eye acupuncture therapy was applied. In medication group, Ibuprofen Sustained Release Capsules was taken with oral administration for 300 mg 1-2 days before menses coming or when the symptoms appeared, once every 12 hours, for 3-5 days totally. Three menstrual periods made one session. The content of PGF2alpha in peripheral blood, and the curative effects and recurrence 3 and 6 months after treatment were observed.

RESULTS

After 3 months treatment, compared with the curative effects between both groups, the cured rate was 55.0% (33/60) and the total effective rate was 95.0% (57/60) in eye acupuncture group, which were superior to those of 34.0% (17/50) and 82.0% (41/50) in medication group (both P < 0.05). According to the following-up after 6 menstrual periods, the recurrence rate was 9.1% (3/33), inferior to that of 35.3% (6/11) in medication group. The contents of PGF2alpha in peripheral blood of menstrual periods were all reduced after treatment in two groups (both P < 0.01).

CONCLUSION

The curative effect of primary dysmenorrhea treated with eye acupuncture is favorable, and the lever of PGF2alpha in peripheral blood of menstrual periods is reduced.

Sodium nitrite downregulates vascular NADPH oxidase and exerts antihypertensive effects in hypertension

Dietary nitrite and nitrate are important sources of nitric oxide (NO). However, the use of nitrite as an antihypertensive drug may be limited by increased oxidative stress associated with hypertension. We evaluated the antihypertensive effects of sodium nitrite given in drinking water for 4 weeks in two-kidney one-clip (2K1C) hypertensive rats and the effects induced by nitrite on NO bioavailability and oxidative stress. We found that, even under the increased oxidative stress conditions present in 2K1C hypertension, nitrite reduced systolic blood pressure in a dose-dependent manner. Whereas treatment with nitrite did not significantly change plasma nitrite concentrations in 2K1C rats, it increased plasma nitrate levels significantly. Surprisingly, nitrite treatment exerted antioxidant effects in both hypertensive and sham-normotensive control rats. A series of in vitro experiments was carried out to show that the antioxidant effects induced by nitrite do not involve direct antioxidant effects or xanthine oxidase activity inhibition. Conversely, nitrite decreased vascular NADPH oxidase activity. Taken together, our results show for the first time that nitrite has antihypertensive effects in 2K1C hypertensive rats, which may be due to its antioxidant properties resulting from vascular NADPH oxidase activity inhibition.

The effect of caloric restriction and glycemic load on measures of oxidative stress and antioxidants in humans: results from the CALERIE Trial of Human Caloric Restriction

Decreasing oxidative stress and increasing antioxidant defense has been hypothesized as one mechanism by which caloric restriction (CR) increases longevity in animals. A total of 46 moderately overweight volunteers (BMI: 25-30 kg/m2), ages 20-42 yr were randomized to either high glycemic (HG) or low glycemic (LG) dietary load CR regimen at either 10% (n=12) or 30% (n=34) of basal caloric intake. All food was provided to participants for 6 mo. Overall, after controlling for CR levels and dietary regimen for 6 mo, plasma glutathione peroxidase activity increased (p=0.04) and plasma protein carbonyl levels decreased (p=0.02) and a non-significant decrease in plasma 8-epi-prostaglandin F2α level was observed (p=0.09). No significant change was observed in other plasma antioxidants such as superoxide dismutase and catalase. These findings indicate that short term CR (10% or 30%) in moderately overweight subjects modulates some but not all measures of antioxidant defense and oxidative stress.

Differences in myocardial PTEN expression and Akt signalling in type 2 diabetic and nondiabetic patients undergoing coronary bypass surgery

OBJECTIVE

Patients with diabetes experience increased cardiovascular complications after cardiac surgery. Hyperglycaemia predicts increased mortality after myocardial infarction and may influence cardiovascular risk in humans. Impaired prosurvival phosphatase and tensin homologue on chromosome 10 (PTEN)-Akt signalling could be an important feature of the diabetic heart rendering it resistant to preconditioning. This study was designed to evaluate for differences and relationships of myocardial PTEN-Akt-related signalling and baseline glycaemic control marker in type 2 diabetic and nondiabetic patients undergoing coronary artery bypass surgery.

METHODS

Right atrial biopsies and coronary sinus blood were obtained from 18 type 2 diabetic and 18 nondiabetic patients intraoperatively. Expression and phosphorylation of Akt, endothelial nitric oxide synthase (eNOS), Bcl-2 and PTEN were evaluated by Western blot. Plasma 15-F(2t) -isoprostane concentrations were evaluated by liquid chromatography-mass spectrometry.

RESULTS

PTEN expression and 15-F(2t) -isoprostane concentrations were significantly higher in diabetic patients. Increased fasting blood glucose levels correlated with increased coronary sinus plasma 15-F(2t) -isoprostane concentrations. Increased cardiac 15-F(2t) -isoprostane generation was highly correlated with myocardial PTEN expression. Bcl-2 expression and eNOS phosphorylation were significantly lower in diabetic compared with nondiabetic patients. Akt phosphorylation tended to be lower in diabetic patients; however, this tendency failed to reach statistical significance.

CONCLUSION

The current results suggest that prosurvival PTEN-Akt signalling is impaired in the diseased diabetic myocardium. Hyperglycaemia and increased oxidative stress may contribute to this phenomenon. These findings strengthen the understanding of the underlying biologic mechanisms of cardiac injury in diabetic patients, which could facilitate development of new treatments to prevent cardiovascular complications in this high-risk population.

Negatively charged low-density lipoprotein is associated with atherogenic risk in hypertensive patients

Negatively charged low-density lipoprotein (LDL), generated via multiple processes such as oxidation, acetylation, or glycosylation, plays a key role in the initiation and progression of atherosclerosis and related diseases. Anion-exchange high-performance liquid chromatography (AE-HPLC) can subfractionate LDL into LDL-1, LDL-2, and LDL-3 based on LDL particle charge, but the clinical significance of LDL subfractions has not yet been elucidated. The aim of this study was to determine the clinical significance of these fractions with particular regard to atherogenic risk in hypertensive patients. Ninety-eight patients with essential hypertension (age 67.0 ± 10.7 years; 54 males) were enrolled in the present study. The relationships between LDL subfractions and atherogenic risk factors, including lipid profiles, blood pressure and plasma 8-isoprostane as a marker of oxidative stress, were examined. LDL-1 levels were significantly and negatively correlated with body mass index (r = -0.384, p < 0.001), systolic blood pressure (r = -0.457, p < 0.001), non-high-density lipoprotein cholesterol levels (r = -0.457, p < 0.001) and 8-isoprostane levels (r = -0.415, p < 0.001). LDL-3, which is the most negatively charged fraction of total LDL, was significantly and positively correlated with these parameters (r = 0.267, 0.481, 0.357, and 0.337, respectively). LDL-1 levels were significantly lower (p < 0.001), and LDL-2 and LDL-3 levels were significantly higher (each p < 0.001) in patients with poorly controlled hypertension than in patients with well-controlled hypertension. In addition, an increase in the total number of traditional risk factors at time of study participation, but not previous diagnosis, was associated with a decrease in LDL-1 levels and increases in LDL-2 and LDL-3 levels. These data suggest that LDL subfractions are associated with multiple atherogenic risk factors and that treatment to modify these risk factors could result in changes in LDL subfraction levels. In conclusion, LDL subfractions isolated by AE-HPLC may represent a marker of atherogenic risk in patients with hypertension.

Weight and inflammation are the major determinants of vascular dysfunction in the aortae of db/db mice

The key roles that obesity, hyperglycemia, hyperlipidemia, inflammation, and oxidative stress play in the progression of diabetes vascular complications are well recognized; however, the relative contribution and importance of these individual factors remain uncertain. At 6, 10, or 14 weeks old, blood samples and thoracic aortae were collected from db/db mice and their non-diabetic controls. Plasma samples were analyzed for glucose, 8-isoprostane, CRP, triglycerides, LDL, and HDL as markers of glycemic status, oxidative stress, inflammation, and dyslipidemia, respectively. The responses of the aortic rings to high KCl, phenylephrine (PE), acetylcholine (ACh), and sodium nitroprusside were examined. Statistical methods were used to estimate the strength of the association between plasma variables and vascular functions. Systemic inflammation occurred in db/db mice at an earlier age than did hyperglycemia or oxidative stress. Aortae of db/db showed augmented contractions to PE which were positively correlated with weight, plasma glucose, 8-isoprostane, and CRP. Also, db/db mice showed impaired endothelium-dependent ACh vasorelaxation which was negatively correlated with weight, plasma glucose, and 8-isoprostane. Multivariate analysis and stepwise modeling show that CRP is the major determinant of the contractile responses, while weight and HDL are the major determinants of ACh-induced relaxation. Among the traditional risk factors of obesity, hyperglycemia, oxidative stress, inflammation, and dyslipidemia, our study reveals that weight and inflammation are the major determinants of vascular dysfunction in the aortae of db/db mice. Our findings partially resolve the complexity of diabetes vasculopathies and suggest targeting weight loss and inflammation for effective therapeutic approaches.

[Metabolomics study of anti-inflammatory action of Radix Paeoniae Rubra and Radix Paeoniae Alba by ultraperformance liquid chromatography-mass spectrometry]

OBJECTIVE

To compare the anti-inflammatory effect of Radix Paeoniae Rubra and Radix Paeoniae Alba by animal experiment and metabolimic analysis.

METHOD

To establish the rats model of toes swelling caused by carrageenan, study the anti-inflammatory effect of Radix Paeoniae Rubra and Radix Paeoniae Alba. The serum samples were analyzed by ultraperformance liquid chromatography-mass spectrometry (UPLC-MS), to find out the potential identification biomarker by PLS-DA.

RESULT

Both of the extracts of Radix Paeoniae Rubra and Radix Paeoniae Alba have good effects of inhibition to swelling caused by carrageenan in 0.5-1 h, and the extract of Radix Paeoniae Rubra also show significant inhibition in 2-3 h. Glutathione( GSH), gamma-aminobutyric acid (GABA), prostaglandin F2alpha (PGF2alpha), prostaglandinE3 (PGE3), leukotrieneA4 (LTA4), prostaglandinE2 ( PGE2) are proven to be significant expressed biomarkers. Radix Paeoniae Rubra and Radix Paeoniae Alba may have great influence on PGF2alpha and PGE3. There was also significant difference between the effects of Radix Paeoniae Rubra and Radix Paeoniae Alba, which suggested the difference of anti-inflammatory between the two herbs.

CONCLUSION

The results of metabolomics are related with the results of classic pharmaco- experiment, which is helpful for the further research of the mechanism of action of Radix Paeoniae Rubra and Radix Paeoniae Alba.

Effect of exenatide on inflammatory and oxidative stress markers in patients with type 2 diabetes mellitus

AIM

This study was designed to determine the effect of exenatide on inflammatory and oxidative stress markers in type 2 diabetes mellitus (T2DM) patients who were suboptimally controlled with metformin and/or sulfonylurea.

SUBJECTS AND METHODS

Twenty-three patients with T2DM with inadequate glucose control were randomly divided into two groups: exenatide group (E group) (12 patients, 5 μg b.d. × 4 weeks followed by 10 μg b.d. × 12 weeks) and placebo group (P group) (11 patients). Glycosylated hemoglobin (HbA1c), the seven-point glucose profile, daily mean glucose, and glycemic excursion were determined. The effects of exenatide on 8-iso-prostaglandin F2α (PGF2α), monocyte chemoattractant protein-1 (MCP-1), and high-sensitivity C-reactive protein (hs-CRP) were investigated.

RESULTS

Exenatide treatment reduced body weight and body mass index (BMI) and improved HbA1c, the seven-point glucose profile, and daily mean glucose compared with placebo (P < 0.05). Limited glycemic excursion was found in the E group compared with the P group (P < 0.05), including a smaller SD and postprandial glucose excursion. In addition, the oxidative stress maker PGF2α was significantly reduced by exenatide treatment (P < 0.05). The inflammatory markers hs-CRP and MCP-1 were also significantly reduced in the E group compared with the P group (P < 0.05). PGF2α was significantly correlated with glycemic excursion (P < 0.05), whereas MCP-1 was significantly correlated with body weight, BMI, glycemic excursion, and HbA1c (P < 0.05 for all).

CONCLUSIONS

Exenatide treatment reduced patient body weight and BMI, improved HbA1c and the seven-point glucose profile, reduced daily mean glucose, limited glycemic excursion, and reduced oxidative stress and inflammatory markers in patients of T2DM having inadequate glucose control.

Concomitance of luteinizing hormone and progesterone oscillations during the transition from preluteolysis to luteolysis in cattle

The temporal relationships of episodes of luteinizing hormone (LH) oscillations, 13,14-dihydro-15-keto-PGF2α (PGFM) pulses, and progesterone (P4) fluctuations during the latter portion of preluteolysis and the early portion of luteolysis were characterized. In Experiment 1, the detection of LH episodes in blood samples collected every 15 min for 8 h was compared with detection in the samples collected every hour in 4 heifers. The number of independently detected episodes/heifer (total = 7) was the same for the 15-min and hourly collection intervals. In Experiment 2, blood samples were collected every hour (n = 7 heifers) and retrospectively assigned to 15 h before and 15 h after the transitional hour between preluteolysis and luteolysis. During preluteolysis, compared with luteolysis, the amplitude of LH oscillations was greater (0.28 ± 0.03 vs 0.18 ± 0.03 ng/mL; P < 0.02) and the interval between peaks of LH oscillations was shorter (3.3 ± 0.3 h vs 4.3 ± 0.6 h; P < 0.04). The LH peaks occurred at the same hour as the peak of a P4 fluctuation in 77% and 29% of LH oscillations (P < 0.0009) during preluteolysis and luteolysis, respectively. In preluteolysis, synchrony between LH and P4 episodes occurred consistently during the P4 rebound after the peak of a PGFM pulse. In luteolysis, the LH peak preceded the peak of the P4 rebound. On a temporal basis, the hypothesis was supported that episodic LH accounts, at least in part, for the reported P4 rebound that occurs after the P4 suppression at the peak of a PGFM pulse.

Serum tryptase level is a better predictor of systemic side effects than prostaglandin D2 metabolites during venom immunotherapy in children

OBJECTIVES

We performed a prospective study to analyze mast cell mediators as predictors of systemic adverse reactions during rush venom-specific immunotherapy (VIT) in children.

PATIENTS AND METHODS

Nineteen children aged 5-17 years received VIT with Venomenhal (HALAllergy). We analyzed serum tryptase (CAP, Phadia), plasma prostaglandin (PG) D2 metabolites (9alpha, 11beta-PGF2), and urine PGD2 metabolites (9alpha, 11beta-PGF2, tetranor-PGD-M) using gas chromatography mass spectrometry before and after the rush protocol.

RESULTS

Three boys with high baseline serum tryptase values (>7.76 g/L) (P < .001) and low 9alpha, 11beta-PGF2 concentrations developed grade III systemic adverse reactions during VIT. Baseline serum tryptase was lowest in children who had a Mueller grade II reaction (1.93 [0.36]) before VIT and highest in children with a Mueller grade III reaction (6.31 [4.80]) (P = .029). Repeated measures analysis of variance confirmed that, in children who developed systemic adverse reactions during VIT, serum tryptase was higher both before and after desensitization and increased significantly following the procedure. Analysis of PGD2 metabolites in the prediction of systemic adverse reactions during VIT was inadequate (sensitivity 67% and specificity 0.53%), whilst prediction based on serum tryptase was accurate.

CONCLUSIONS

In children with severe systemic adverse reactions to Hymenoptera sting, the evaluation of baseline tryptase levels should be a standard procedure. Children with Apis mellifera venom allergy and baseline tryptase levels higher than 7.75 g/L are at risk of anaphylaxis during buildup. Lower baseline values of plasma and urinary PGD2 metabolite concentration in patients with systemic adverse reaction during VIT suggest that prostaglandin catabolism is altered.

[Effects of simvastatin on plasma SOD, MDA and 8-iso-PGF2α in patients with stable angina]

To observe the effects of simvastatin on plasma superoxide dismutase (SOD), malonaldehyde (MDA) and 8-iso-prostaglandin F2α (8-iso-PGF2α) as well as uric acid (UA) and serum lipids in patients with stable angina. METHODS Eighty-five patients with stable angina were divided into 4 groups, including hyperlipemia treatment group (HLT), hyperlipemia control group (HLC), normolipemia treatment group (NLT), and normolipemia control group (NLC). All the patients received routine treatment according to the guideline of CHD treatment, and those in the treatment groups were given Simvastatin (40 mg) every night, whereas those in the control group received placebo for 3 months. Before and after the treatments, the levels of plasma 8-iso-PGF2α were measured by enzyme-linked immunosorbent assay, and the plasma levels of SOD and MDA were detected by colorimetric method. LDL, HDL, TC, TG, and UA were also measured biochemically. RESULTS Compared with the control group, both of the treatment groups showed significantly increased levels of SOD and decreased MDA, 8-iso-PGF2α, UA and plasma lipids after the treatments (P<0.05). CONCLUSION In patients with coronary heart disease, simvastatins can decrease plasma lipids, inhibit lipid peroxidations, and promote the clearance of free radicals, thereby alleviating the oxidative stress.

Effects of fenofibrate on plasma oxidized LDL and 8-isoprostane in a sub-cohort of GOLDN participants

BACKGROUND

Fenofibrate significantly reduces circulating triglyceride (TG) concentrations, particularly in individuals with elevated levels. The purpose of the current study was to determine whether fenofibrate treatment reduces markers of oxidative stress, oxidized low density lipoprotein (ox-LDL) and 8-isoprostane (8-isoP), in a manner similar to TG where those with the highest levels show the greatest reductions.

MATERIALS/METHODS

The concentrations of TG, 8-isoP, and ox-LDL were measured in plasma before and after 3 weeks of fenofibrate treatment (160 mg/d) in a sub-cohort (n=187) of the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN) study.

RESULTS

Data were divided into tertiles as determined by pre-treatment values of the respective target. Fenofibrate treatment resulted in significant reductions in TG concentrations by 24.2% (p<0.0001), 41.9% (p < 0.0001), and 46.6% (p < 0.0001) in tertiles 1, 2, and 3, respectively. Significant reductions were also observed in ox-LDL of 7.2% (p=0.0096), 8.5% (p = 0.0019) and 12.1% (p < 0.0001) in tertiles 1, 2, and 3, respectively. Finally, fenofibrate treatment resulted in a 32.7% increase (p=0.0201) in 8-isoP levels in tertile 1, but a significant decrease of 34.4% (p < 0.0001) in tertile 3.

CONCLUSIONS

This study is the largest to date to demonstrate that fenofibrate reduces oxidative stress and the first to show a suppressive effect on 8-isoP levels in individuals with a high oxidative burden following short term (3 wk) drug therapy. Those with the highest baseline levels of ox-LDL and 8-isoP showed the greatest reductions following fenofibrate treatment. Given the role of oxidative stress in atherosclerosis and coronary heart disease, our observations may partially explain the efficacy of fenofibrate in reducing cardiovascular events in select patients.

[Concentration of 8-isoprostaglandin F2alpha depending on type of anesthesia in laparoscopic surgery in gynecology]

The article represents a randomized comparative study including 100 patients from 21 to 34 years old who has underwent a laparoscopic surgery in V. I. Kulakov Research Center of Obstetrics, Gynaecology, and Perinatology in 2007-2009. Patients were anaesthetized either with a spinal anaesthesia at L3-L4 level with bupivacaine or with a multi-component general anaesthesia using fentanyl, midazolam, propofol, rocuronium and artificial lung ventilation. Assessment of the serum 8-isoprostaglandin F2alpha before the surgery and 2 hours after the end of surgery has shown the increase of this oxidative stress marker in the early post-surgery period. However, in spinal anaesthesia group, the increase was significantly lower, indicating a more physiological nature of this method of anaesthesia.

Effect of estrus induction on prostaglandin content and prostaglandin synthesis enzyme expression in the uterus of early pregnant pigs

Prostaglandins (PGs) play a pivotal role in maternal recognition of pregnancy and implantation in pigs. In the present study, PGE(2), PGF(2alpha), and PGFM (PGF(2alpha) metabolite) content, as well as PGE(2) synthase (mPGES-1) and PGF(2alpha) synthase (PGFS) expression was investigated in early pregnant gilts with natural (n=21) and PMSG/hCG-stimulated (n=19) estrus. Endometrial tissue samples, uterine luminal flushings (ULFs), and blood serum were collected on days 10-11, 12, and 15 after insemination. Additionally, day 15 conceptuses were collected for mPGES-1 and PGFS protein expression. Effect of estrus induction was observed on day 15 of pregnancy, when the content of PGE(2) in the uterine lumen was fourfold lower in gonadotropin-stimulated gilts in comparison to controls (P<0.001). Decreased PGE(2) content in ULFs of gonadotropin-treated pigs was preceded by lower endometrial mPGES-1 gene expression in hormonally-stimulated animals in comparison to control gilts (P<0.01). On the other hand, estrus induction with PMSG/hCG resulted in higher PGE(2) accumulation in the endometrial tissue on day 15 of pregnancy (P<0.01). Furthermore, PGF(2alpha) content in the endometrium and PGFM levels in blood serum were lower in gonadotropin-treated gilts, especially on day 12 after insemination when compared to control gilts (P<0.01). Finally, PGFS expression in day 15 conceptuses was decreased in animals with hormonally-induced estrus. We conclude that PMSG/hCG stimulation of prepubertal gilts to induce estrus results in changes of PG production and secretion during early pregnancy, which, in turn, may affect conceptus development, implantation, and the course of pregnancy.

Relationships between glucose excursion and the activation of oxidative stress in patients with newly diagnosed type 2 diabetes or impaired glucose regulation

The effect of glucose excursions on oxidative stress is an important topic in diabetes research. We investigated this relationship by analyzing markers of oxidative stress and glycemic data from a continuous glucose monitoring system (CGMS) in 30 individuals with normal glucose regulation (NGR), 27 subjects with impaired glucose regulation (IGR), and 27 patients with newly diagnosed type 2 diabetes (T2DM). We compared the mean amplitude of glycemic excursion (MAGE), mean postprandial glucose excursion (MPPGE), and mean postprandial incremental area under the curve (IAUC) with plasma levels of oxidative stress markers 8-iso-PGF2α, 8-OH-dG, and protein carbonyl content in the study subjects. Patients with T2DM or IGR had significantly higher glucose excursions and plasma levels of oxidative stress markers compared to normal controls (P < 0.01 or 0.05). Multiple linear regression analyses showed significant relationships between MAGE and plasma 8-iso-PGF2α, and between MPPGE and plasma 8-OH-dG in patients with IGR or T2DM (P < 0.01 or 0.05). Furthermore, 2h-postprandial glucose level and IAUC were related to plasma protein carbonyl content in the study cohort including T2DM and IGR (P < 0.01). We demonstrate that glucose excursions in subjects with IGR and T2DM trigger the activation of oxidative stress.

Elevated levels of 8-iso-prostaglandin F2alpha in acute coronary syndromes are associated with systemic and local platelet activation

INTRODUCTION

Oxidative stress is an important causative factor in atherosclerosis. Isoprostanes are derivatives of arachidonate oxidized by reactive oxygen species (ROS). Oxidized lipids are markers of oxidative stress, important mediators of atherosclerosis, and activators of platelets. 8-iso-prostaglandin F2alpha (8-iso-PGF2alpha) is a stable isoprostane and reliable marker of oxidative stress in vivo.

OBJECTIVES

The aim of the study was to determine the level of oxidative stress in acute coronary syndromes (ACS) and its correlations with the para meters of hemo stasis.

PATIENTS AND METHODS

Fourty-nine patients aged 46 to 76 years, including 28 with ACS and 25 with stable coronary artery disease (CAD), were enrolled to the study. The levels of 8-iso-PGF2alpha, soluble CD40 ligand (sCD40L), P-selectin (P-sel), beta-thromboglobulin, and the thrombin-antithrombin complex (TAT) in the plasma of venous blood were determined. A microvascular injury model was also used to evaluate TAT generation and sCD40L levels in blood collected every 60 seconds at the site of standardized microvascular injury.

RESULTS

8-iso-PGF2alpha levels were significantly higher in ACS compared to CAD patients (363.2 +/-45.94 vs. 328.2 -/+31.96 pg/ml, P = 0.011) and correlated with venous plasma levels of P-sel and beta-thromboglobulin in the ACS (r = 0.66; P = 0.0005 and r = 0.62; P = 0.001, respectively) and CAD groups (r = 0.46; P = 0.02 and r = 0.49; P = 0.01, respectively). In the microvascular injury model, the maximum concentrations of sCD40L in the ACS group were associated with plasma 8-iso-PGF2alpha levels (r = 0.50, P = 0.01). No correlations between 8-iso-PGF2alpha and markers of thrombin generation in venous blood and microvascular injury model were observed.

CONCLUSIONS

Plasma levels of 8-iso-PGF2alpha are significantly higher in ACS compared with stable CAD and correlate with platelet activation.

Hypercholesterolemia, oxidative stress and gender dependence in children

Hypercholesterolemia (HCH) is characterized by an increase of the total- and LDL-cholesterol in serum. In hypercholesterolemia, generally recognized as a risk factor of atherogenesis, oxidative stress and oxidatively modified LDL play a crucial role. In our study, children with elevated total cholesterol (above 4.5 mmol/l) were included. Parameters of lipid profile, lipophilic vitamins and antioxidants (retinol, α-tocopherol, γ-tocopherol, xantophyll, lycophen and β-carotene) and markers of oxidative damage to lipids (lipoperoxides and 8-isoprostanes) were evaluated. We found that children with hypercholesterolemia have significantly increased parameters of lipid profile and these are gender dependent only in HDL-cholesterol (1.27 ± 0.10 mmol/l in boys vs. 1.53 ± 0.07 mmol/l in girls; p<0.05) and TAG (1.63 ± 0.31 mmol/l in boys vs. 1.08 ± 0.09 mmol/l in girls; p<0.05). In addition, children with HCH have decreased total antioxidant capacity of serum (TEAC) (about 19.64%, p<0.05) and increased lipoperoxides (LP) (about 45.73%, p<0.001). We have revealed statistically significant correlations between parameters of lipid profile and lipophilic vitamins and antioxidants, as well as between markers of oxidative stress: positive correlation between LP and 8-iso (r=0.353, n=33, p<0.05) and negative correlations between these parameters and TEAC (r= -0.377, n=33, p<0.05 for LP and r= -0.379, n=33, p<0.05 for 8-iso). In conclusion, we confirmed relation between hypercholesterolemia and oxidative stress and effect of gender on these processes already in childhood. Since the atherosclerotic process begins in childhood before clinical symptoms, early detection of hypercholesterolemia and oxidative stress is important in later atherosclerosis prevention.

Antioxidative activity of sulodexide, a glycosaminoglycan, in patients with stable coronary artery disease: a pilot study

BACKGROUND

Oxidative stress may promote chronic inflammation and contribute to accelerated atherogenesis in patients with coronary artery disease (CAD). Sulodexide, a glycosaminoglycan consisting primarily of heparin, has been shown to affect oxidative stress in experimental settings. The purpose of this pilot study was to determine the effect of sulodexide administration on oxidative stress, inflammation and plasma lipids in patients with proven stable CAD.

MATERIAL/METHODS

Fifty-six optimally treated male CAD patients (pts), mean age 57+/-6 yrs, were randomized to either 8 weeks of sulodexide treatment (SUL, n=28), or to a control group (n=28). At baseline and at the end of the study, all pts underwent full clinical and standard laboratory plasma level assessment of lipids, markers of inflammation, and 8-isoprostane, as a sensitive index of oxidative stress.

RESULTS

At entry the 2 groups did not differ significantly in terms of age, coronary risk factors, clinical status and concomitant medication. SUL treatment appeared to be safe and caused a significant decrease in the level of plasma 8-isoprostane (77.4 vs 44.5 pg/ml, p<0.0001) compared with controls (75.7 vs 68.3 pg/ml, p=NS). In contrast, neither LDL cholesterol (2.71 vs 2.72 mmol/l) and triglycerides (1.38 vs 1.43 mmol/l), nor markers of inflammation - fibrinogen (3.7 vs 3.6 g/l), C-reactive protein (0.14 vs 0.13 mg/l), leukocyte count (6.33 vs 6.32x10(9)/l) - were affected by SUL treatment.

CONCLUSIONS

Sulodexide administration resulted in significant reduction in oxidative stress in stable CAD patients, and neither the changes in cholesterol metabolism nor in systemic inflammation underlay this effect.

Ultrastructural response of arcuate nucleus neurons to fasting in aged rats

The arcuate nucleus of the hypothalamus (ARH) is involved in the control of energy homeostasis. Leptin - an adipocyte derived hormone - is known to act on the hypothalamic nuclei and thus to control body weight by food intake reduction. Oxidative stress is believed to be implicated in leptin signalling. However, its relevance for leptin-induced signal transduction within ARH remains unclear. The goal of the study was to investigate the effect of fasting on morphological alterations of the neuronal endoplasmic reticulum/Golgi network as well as on the expression of leptin receptors in the arcuate nucleus of aged rats. Male Wistar rats, aged 24 months, were fasted for 96 hours. The control animals were fed ad libitum. Membranous whorls in the ARH neurons were visualized using the electron microscopy technique. Leptin receptors in the membranes of ARH neurons were determined immunohistochemically (IHC), and soluble leptin receptors in the plasma as well as plasma isoprostanes were quantified immunochemically (ELISA). An intense formation of membranous whorls was observed, directly associated with the cisternae of the rough endoplasmic reticulum, as well as lamellar bodies. Interestingly, the whorls were often localized near a well-developed Golgi complex. Moreover, some Golgi complexes displayed an early stage of whorl formation. Groups of residual lipofuscin granules were found in the immediate proximity of the whorls. An increased immunoreactivity with neuronal leptin receptors suggests that hypersensitive neurons may still effectively respond to the fasting serum levels of leptin, mediating ultrastructural transformation of ARH neurons during short-term fasting. Having observed a significant accumulation of lipofuscin granules and a marked increase of total 8-isoprostane serum level in the fasting rats, we hypothesize that signal transduction within the neurons of ARH is dependent on oxidative stress phenomena.

Determination of 8-epi PGF(2alpha) concentrations as a biomarker of oxidative stress using triple-stage liquid chromatography/tandem mass spectrometry

F2-isoprostanes are a family of prostaglandin F2-like compounds that are formed by free-radical-catalyzed peroxidation of arachidonic acid. Several F2-isoprostanes, but in particular 8-epi PGF(2alpha), are widely used as oxidative stress biomarkers. An analytical method based on liquid chromatography with negative electrospray ionization (ESI) coupled to tandem mass spectrometric detection (LC/MS/MS) was developed for the determination of 8-epi PGF(2alpha) concentrations in human plasma, whole blood, erythrocytes and urine. 8-epi PGF(2alpha)-d4, a stable isotope derivative of 8-epi PGF(2alpha), was used as an internal standard (IS). A 50 microL sample was focused on-column and separated on two 3 microm particle size SUPELCOSIL ABZ+Plus HPLC columns (15 cm x 4.6 mm and 7.5 cm x 4.6 mm) connected in series. An Applied Biosystems 4000 Q TRAP LC/MS/MS system with ESI was operated in multiple reaction monitoring (MRM) mode with the precursor-to-product ion transitions m/z 353.4 --> 193.1 (8-epi PGF(2alpha)), 357.4 --> 197.1 (8-epi PGF(2alpha)-d4), used for quantification. The assay was fully validated and found to have adequate accuracy, precision, linearity, sensitivity and selectivity. The mass limit of detection (mLOD) was 1 pg of analyte eluting from the column. The assay has been successfully applied to the analysis of human plasma, whole blood, erythrocytes and urine samples.

The effect of fasting on the ultrastructure of the hypothalamic arcuate nucleus in young rats

In the present study, we described ultrastructural changes occurring in the neurons of the hypothalamic arcuate nucleus after food deprivation. Young male Wistar rats (5 months old, n = 12) were divided into three groups. The animals in Group I were used as control (normally fed), and the rats in Groups II and III were fasted for 48 hours and 96 hours, respectively. In both treated groups, fasting caused rearrangement of the rough endoplasmic reticulum forming lamellar bodies and membranous whorls. The lamellar bodies were rather short in the controls, whereas in the fasting animals they became longer and were sometimes participating in the formation of membranous whorls composed of the concentric layers of the smooth endoplasmic reticulum. The whorls were often placed in the vicinity of a very well developed Golgi complex. Some Golgi complexes displayed an early stage of whorl formation. Moreover, an increased serum level of 8-isoprostanes, being a reliable marker of total oxidative stress in the body, was observed in both fasting groups of rats as compared to the control.

Role of follicular estradiol-17beta in timing of luteolysis in heifers

The hypothesis was tested that estradiol (E2) from the ovarian follicles controls time of luteolysis. Time of luteolysis was evaluated by multiple measures of corpus luteum (CL) structure (area, volume) and function (progesterone [P4], luteal blood flow). The hypothesis for experiment 1 was that repeated ablation of follicles would reduce circulating E2 and delay luteolysis. Heifers were randomly assigned on Day 9 (Day 0 = ovulation) to three groups. All follicles >or=4 mm were ablated on Day 9 (group FA9; n = 6); Days 9-15 (group FA15; n = 6); or Days 9-21 (group FA21; n = 7). As expected, follicular ablation delayed (P < 0.001) the rise in circulating E2 and peak E2 concentrations (FA9, Day 17.6 +/- 0.7; FA15, Day 20.3 +/- 0.3; FA21, Day 24.9 +/- 0.3). Luteolysis (based on each measure) was delayed (P < 0.005) by repeated ablation of follicles, with earlier luteolysis (based on P4 decrease) in FA9 (Day 15.2 +/- 0.8) than FA15 (Day 16.5 +/- 0.4), and a further delay in FA21 (Day 18.3 +/- 0.5). The hypothesis of experiment 2 was that exogenous treatment with E2 would stimulate prostaglandin F(2alpha) (PGF) secretion and prevent the delay in luteolysis associated with follicular ablations. Follicles >or=4 mm were ablated from Day 9 to Day 17 (n = 15). Heifers were treated on Days 13 and 15 with 1.0 mg of estradiol benzoate (FAE2; n = 7) or vehicle (FAV; n = 8). Treatment with E2 induced PGF secretion (detected by PGF metabolite) and induced earlier (P < 0.02) luteolysis in FAE2 than in FAV, whether determined by circulating P4 or by area, volume, or blood flow of CL. In summary, ablation of follicles (>or=4 mm) delayed and treatment with E2 hastened luteolysis in heifers with ablated follicles. Thus, these results are consistent with an essential role for follicle E2 in timing of luteolysis.

Evidence for relaxin and progesterone synchronous secretion on days 13 to 17 of the oestrous cycle in sows

Concentrations of relaxin in both the utero-ovarian vein (UOV) and jugular vein (JV) as well as those of progesterone and prostaglandin F2 alpha in the UOV were studied on Days 13-17 of the oestrous cycle in sows. Mean relaxin plasma concentrations in the UOV and JV were correlated (r = 0.55; P less than 0.001) and were significantly higher (P less than 0.01) in the UOV (1.67 +/- 0.07 ng/ml), than in the JV (0.59 +/- 0.1 ng/ml). The great similarity between relaxin and progesterone profiles was ascertained (r = 0.57; P less than 0.001). The steep decrease of progesterone plasma concentration on the day of luteolysis was observed together with synchronous relaxin concentration decline. A significant correlation between relaxin and PGF2 alpha plasma concentration was demonstrated one day before luteolysis (r = 0.41; P less than 0.001).

Oxidative Stress and Myocardial Damage during Elective Percutaneous Coronary Interventions and Coronary AngiographyA Comparison of Blood-borne Isoprostane and Troponin Release

The role of oxidative stress in clinical cardiology is still controversial. The aims of the present study were to examine if minor ischaemic episodes as may occur during elective percutaneous coronary intervention (PCI) induce oxidative stress and, eventually, if oxygen stress correlates with myocardial injury. Thirty eight and nine patients underwent PCI and diagnostic coronary angiography, respectively. Peripheral blood was sampled at different time points for plasma analyses of: 8-iso-PGF2alpha (free radical-mediated oxidative stress); 15-keto-dihydro-PGF2alpha (cyclooxygenase-mediated inflammation); troponin-T (myocardial injury); hsCRP, vitamin A and vitamin E; and, total antioxidants status (TAS). In both groups 8-iso-PGF2alpha increased transiently by approximately 80% (p < 0.001) during the procedure. There was a minor troponin-T release (p < 0.001) after PCI, but no correlation with 8-iso-PGF2alpha. Troponin-T did not increase after angiography. 15-keto-dihydro-PGF2alpha decreased by 50% after ended procedure, but increased by 100% after 24 h compared to baseline. hsCRP increased significantly (p < 0.001) from baseline to the next day in the PCI-group, but not in the angiography group. Vitamins and TAS decreased slightly after the procedures. It is concluded that a moderate oxidative stress was induced by both elective PCI and coronary angiography but that no correlation was found between oxidative stress and myocardial injury in this setting. This indicates that other mechanisms than ischaemia-reperfusion episodes caused an elevation in plasma isoprostane such like the injury at a vascular site mutual for both procedures. A secondary finding from the study was elevated markers of early inflammatory response, not only after PCI, but also after angiography.

F2-isoprostane induced prostaglandin formation in the rabbit

F(2)-isoprostanes, non-enzymatic free radical mediated products of arachidonic acid, have shown to form during various oxidant stress status and have potent biological effects. This study investigates to what extent 8-iso-PGF(2alpha) (a major F(2)-isoprostane), a bioactive product of lipid peroxidation can modify endogenous prostaglandin F(2alpha) (PGF(2alpha)) formation since prostaglandins are inflammatory as well as potent vasoregulatory substances that modulate diverse important physiological functions, and also form during acute and chronic inflammation. An immediate appearance and disappearance of 8-iso-PGF(2alpha) was seen in both plasma and urine within a short interval after i.v. administration of 43 microg/kg of 8-iso-PGF(2alpha) to the rabbits. A successive but differential formation of PGF(2alpha) resulted in a rapid and pulsatile increase of plasma 15-keto-dihydro-PGF(2alpha), a major metabolite of primary PGF(2alpha). Later, this compound was excreted efficiently as intact compound into the urine during the 3 h of experiment. A 8-fold increase of PGF(2alpha) metabolite in plasma at 10 min and 12-fold increase in the urine at 30-60 after the i.v. administration of 8-iso-PGF(2alpha) was observed which continued throughout the 3 h of experiment. This observation suggests that pharmacologically administered or endogenously produced 8-iso-PGF(2alpha) during oxidant stress induces prostaglandin formation presumably through the classical cyclooxygenase-catalysed arachidonic acid oxidation which might be inflammatory itself to the cells and exerts further vasoconstrictive effects.

Plasma 8-iso-prostaglandin F2α, a marker of oxidative stress, is increased in patients with acute myocardial infarction

BACKGROUND

Oxidative stress has been implicated in the pathogenesis of atherogenesis. The aim of our study is to examine whether the plasma 8-iso-prostaglandin F(2alpha) level, a marker of oxidative stress, is elevated in patients with acute myocardial infarction.

METHODS

Three groups of patients were enrolled: (1) patients with no or minimal coronary artery disease (CAD) (n = 15); (2) patients with stable CAD (n = 31); (3) patients with acute myocardial infarction (n = 13).

RESULTS

Plasma 8-iso-prostaglandin F(2alpha) levels were significantly elevated (p < 0.001) in patients with acute myocardial infarction (290.7 +/- 73.9 pg/ml) as compared to patients with stable CAD (182.0+75.7 pg/ml) and patients with no significant CAD (118.9 +/- 85.5 pg/ml). This remained significant after correcting for coronary atherosclerosis risk factors, age, extent of atherosclerosis, and C-reactive protein (CRP) level.

CONCLUSION

Plasma 8-iso-prostaglandin F(2alpha) levels are elevated in patients with acute myocardial infarction. Endogenous oxidative stress may contribute to the pathogenesis of atherosclerosis and its complications, namely myocardial infarction.

Aspirin resistance in coronary artery disease is correlated to elevated markers for oxidative stress but not to the expression of cyclooxygenase (COX) 1/2, a novel COX-1 polymorphism or the PlA1/2polymorphism

Aspirin resistance (AR) is estimated to be present in 5-75% of patients and is related to increased cardiovascular mortality. However, the underlying mechanisms are mostly unknown. In the present study, AR was detected in 14 out of 55 patients (25%) with coronary artery disease. The presence of concomitant anti-inflammatory drugs did not affect AR. Plasma levels of thromboxane B(2) as well as the markers for oxidative stress and known platelet activators 8-isoprostane and lipid peroxidation products were significantly higher in aspirin-resistant individuals (349.3 pg/ml, 53.9 pg/ml, and 538 micromol/l) compared to controls (113.7 pg/ml, 10.3 pg/ml, and 32.2 micromol/l; P < 0.05, respectively). Platelet cyclooxygenase-1 (COX-1) and COX-2 mRNA and protein expression were without significant differences between the two groups. DNA sequencing detected a novel platelet COX-1 single nucleotide polymorphism (SNP) resulting in amino acid exchange at position 8 (Arg8/Trp8). The wild-type as well as the heterozygous and homozygous SNP were present in both patient groups without significant differences. The aspirin binding (Arg120) and acetylation site (Ser529) were unaffected in the samples tested. Neither was AR related to the platelet integrin PlA(1)/A(2) polymorphism. In conclusion, AR appears to be unrelated to differences in platelet COX-1 and COX-2 expression or to a novel platelet COX-1 SNP and the PlA(1)/A(2) SNP. However, a correlation exists to elevated eicosanoids generated by oxidative stress indicating COX-1-independent pathways for the generation of platelet activating molecules represent a potential cause for AR.

Intake of Mediterranean vegetable soup treated by pulsed electric fields affects plasma vitamin C and antioxidant biomarkers in humans

The bioavailability of vitamin C from pulsed electric fields (PEF)-treated vegetable soup in comparison with freshly made (FM) vegetable soup-gazpacho-and its impact on 8-epiPGF(2alpha) and uric acid concentrations in a human population were assessed. For this purpose six subjects consumed 500 ml PEF-treated vegetable soup/day, and six subjects consumed 500 ml FM vegetable soup/day for 14 days. On the first day of the study, the subjects drank the vegetable soup in one dose (dose-response study), and on days 2-14 they consumed 250 ml in the morning and 250 ml in the afternoon (multiple-dose-response study). Blood was collected every hour for 6 h on the first day and again on days 7 and 14. All blood samples were analyzed for vitamin C, 8-epiPGF(2alpha), and uric acid. The maximum increase in plasma vitamin C occurred 3 h post-dose in both the PEF and the FM groups. Vitamin C remained significantly higher (P = 0.05) on days 7 and 14. The plasma 8-epiPGF(2alpha) concentration was significantly lower at the end of the study in both the PEF group (P = 0.002) and the FM group (P = 0.05). Plasma levels of vitamin C and 8-epiPGF(2alpha) were inversely correlated in both groups (r= -0.549, P = 0.018; and r = -0.743, P = 0.0004, respectively). To summarize, drinking two servings (500 ml) of PEF-treated or FM gazpacho daily increases plasma vitamin C and significantly decreases 8-epiPGF(2alpha) concentrations in healthy humans.

Rapid and easy method for monitoring oxidative stress markers in body fluids of patients with asbestos or silica-induced lung diseases

Sensitive assay method was developed for a parallel, rapid and precise determination of the most prominent oxidative stress biomarkers: 8-iso-prostaglandin F(2alpha), malondialdehyde and 4-hydroxynonenal. The method consisted of a pre-treatment part a solid-phase extraction, for rapid and effective isolation of biomarkers from body fluids (exhaled breath condensate, plasma and urine) and the detection method LC-ESI-MS/MS, where the selected reaction monitoring mode was used for its extremely high degree of selectivity and the stable-isotope-dilution assay for its high precision of quantification. The developed method was characterized by the following parameters: the imprecision was below 14.3%, the mean inaccuracy was determined to be lower than 13.1%. The method was tested on samples obtained from patients diagnosed with asbestosis, pleural hyalinosis or silicosis, i.e. occupational lung diseases caused by fibrogenic dusts, inducing oxidative stress in the respiratory system, and then compared to samples from healthy subjects. The difference in concentration levels of biomarkers between the two groups was perceptible in all the body fluids (the difference observed in an exhaled breath condensate was statistically most significant).

[Primary study on the effects of high-salt diet on the myocardium and the related mechanisms]

OBJECTIVE

The study was to evaluate the effects of high-salt diet on the blood pressure and myocardium in Sprague-Dawley rats and to investigate the related mechanisms.

METHODS

Rat model of high-salt diet was established by receiving standard rat chow with salt concentration of 0.3% and additional salt load via the drinking water (1% sodium chloride solution). Systolic blood pressure was measured by The indirect tail-cuff method in the rats on high-salt and normal-salt diet. The rats were placed in metabolic cages. Food intake and urine volume were recorded. The sodium and chloride in plasma and urine were measured. Transthoracic echocardiographic studies were performed at the eighth week with an echocardiographic system. The pathological variations of the myocardium were observed by the electron microscopy. The p22phox and p47phox mRNA expressions were analyzed by real time RT-PCR. The p22phox and p47phox protein expressions were analyzed by Western blot. The NADPH oxidase activity of myocardium and the serum 8-isoprostane levels were measured.

RESULTS

Left ventricular hypertrophy (all P < 0.05) and the decreased diastolic function of left ventricle without significantly elevated blood pressure [(128 +/- 4) mm Hg versus (125 +/- 3) mm Hg in controls, P > 0.05] were found in the rats on high-salt diet, compared to those in the rats on normal-salt diet. Furthermore, mRNA and protein expressions of the p22phox and p47phox, and the NADPH oxidase activity of myocardium were increased [(0.332 +/- 0.015) micromol x min(-1) x mg(-1) versus (0.142 +/- 0.023) micromol x min(-1) x mg(-1) in controls, P <0.05]. Serum 8-isoprostane levels [(1117 +/- 86) pg/ml versus (327 +/- 80) pg/ml in controls, P < 0.05] were also significantly increased in the rats on high-salt diet.

CONCLUSION

High-salt diet might lead to left ventricular hypertrophy and the decreased diastolic function of left ventricle through oxidative stress without significantly elevated blood pressure.

COX-2-mediated inflammation in fat is crucial for obesity-linked insulin resistance and fatty liver

The aim was to examine the role of cyclooxygenase (COX)-2-mediated inflammation in the development of obese linked insulin resistance and fatty liver. The rats were fed separately regular diet (CONT), high-fat diet (HFD) ad libitum, or energy restrictedly for 12 weeks. Rats fed HFD ad libitum were further divided into three subgroups co-treated with vehicle (HFa), or a selective COX-2 inhibitor celecoxib (HFa-Cel) or mesulid (HFa-Mes). Euglycemic hyperinsulinemic clamp (EHC) experiment was performed at the end of study. Another set of rats with similar grouping was further divided into those with a 4, 8, or 12-week intervention period for hepatic sampling. Body weight was increased significantly and similarly in HFa, HFa-Cel, and HFa-Mes. Time-dependent increases in plasma insulin, glucose, 8-isoprostanes, leptin levels, homeostasis model assessment of insulin resistance (HOMA-IR) and hepatic triglyceride contents shown in HFa were significantly reversed in HFa-Cel and HFa-Mes. During EHC period, the reduction in stimulation of whole body glucose uptake, suppression of hepatic glucose production and metabolic clearance rate of insulin shown in HFa were significantly reversed in HFa-Cel and HFa-Mes. The enhanced COX-2 and tumor necrosis factor-alpha (TNF-alpha) but attenuated PPAR-gamma and C/EBP-alpha mRNA expressions in epididymal fat shown in HFa were significantly reversed in HFa-Cel and HFa-Mes. The increases in average cell size of adipocytes and CD68 positive cells shown in HFa were also significantly reversed in HFa-Cel and HFa-Mes. Our findings suggest that COX-2 activation in fat inflammation is important in the development of insulin resistance and fatty liver in high fat induced obese rats.

Ultrastructural observations on the hypothalamic arcuate nuclei of aged rats in the fasting/refeeding model

The arcuate nucleus of the hypothalamus (ARH) is involved in the control of energy homeostasis. This is the first study on the ultrastructural response of ARH neurons in aged rats after short-term fasting and subsequent refeeding. Male Wistar rats (24 weeks old) were fasted for 48 or 96 hours and were then refed for 24 hours. The controls were normally fed. The rats received water ad libitum. In both groups of fasting animals, we observed a rearrangement of the arcuate rough endoplasmic reticulum (RER) and Golgi complexes to form membranous whorls. Moreover, refeeding for 24 hours did not reverse this process. The RER was frequently found to be well organized into lamellar bodies composed of several cisternae. The membranous whorls were composed of concentric layers of endoplasmic reticulum and Golgi complexes. In addition, multiform lipofuscin granules were observed in close relationship with Golgi complexes and membranous whorls. Lipofuscin granules within the neurons of the arcuate nucleus are assumed to be a morphological manifestation of oxidative stress phenomena, which are presumably implicated in the formation of membranous whorls in both fasting and fasting/refed animals. This observation correlates with a significant increase in 8-isoprostane serum levels in the fasting and fasting/refed animals as compared to the fed control rats.

Importance of cyclooxygenase 2-mediated low-grade inflammation in the development of fructose-induced insulin resistance in rats

This study was designed to examine the role of cyclooxygenase (COX) 2-mediated low-grade inflammation in the development of fructose-induced whole body and muscular insulin resistance in rats. The rats were on regular or fructose-enriched diets for 8 weeks. Fructose-fed rats were further divided into 3 groups (n = 8 per group). There were fructose-fed rats, fructose-fed rats with nimesulide (a selective COX2 inhibitor, 30 mg/kg/day, gavage) and fructose-fed rats with celecoxib (a selective COX2 inhibitor, 30 mg/kg/day, gavage). The present result showed that fructose-induced time-dependent increases in systolic blood pressure and fasting plasma insulin and triglyceride levels were significantly suppressed in rats treated with nimesulide or cerecoxib. The ratio of area under glucose curve divided by area under insulin curve obtained during the oral glucose tolerance test was significantly decreased in fructose-fed rats, which were markedly reversed in those co-treated with nimesulide or celecoxib. Accordingly, fructose-induced decrease in insulin-stimulated glucose uptake in soleus muscle was significantly reversed in those combined with nimesulide or celecoxib. Fructose-induced time-dependent increases in plasma 8-isoprostane and PGE metabolites were concomitantly suppressed by nimesulide or celecoxib co-treatment. The present study demonstrates that the COX2-mediated low-grade inflammation, especially mediated by increase in oxidative stress was important in the development of insulin resistance in fructose-fed rats.

[Observation on therapeutic effect of acupoint application on dysmenorrhea of excess syndrome and effect on prostaglandins]

OBJECTIVE

To observe therapeutic effect of acupoint application on dysmenorrhea of excess syndrome and its effect on prostaglandins.

METHODS

The patients with primary dysmenorrhea of excess syndrome were randomly divided into an application group and a medication group. The application group of 31 cases were treated with application of Chinese medicine composed of Zhinanxing (Rhizoma Arisaematis), Sanleng (Rhizoma Sparganii), Ezhu (Rhizoma Zedoariae), etc. at Zhongji (CV 3), Guanyuan (CV 4), Qihai (CV 6); and the medication group of 30 cases were treated with oral administration of Tianqi Tongjing Capsules. The scores for the pain degrees and the duration of dysmenorrhea were observed and prostaglandin F2alpha (PGF2alpha) and prostaglandin E2 (PGE2) contents in peripheral blood were determined before and after treatment.

RESULTS

The total effective rate of 93.5% in the application group was significantly better than 73.3% in the medication group (P < 0.05); after treatment, the scores of the symptoms were significantly decreased in the two groups (both P < 0.01), with more obvious improvement in the application group than the medication group (P < 0.01). The PGE2 content was significantly increased, and the PGF2alpha content and PGF2alpha/PGE2 were significantly decreased in the application group (all P < 0.01).

CONCLUSION

Acupoint application has a better therapeutic effect on dysmenorrhea of excess syndrome and has benign regulative action on synthesis of prostaglandins in the patients with primary dysmenorrhea.

[Correlation between the amplitude of glucose excursion and plasma 8-iso prostaglandin F2alpha level in subjects with different types of glucose regulation]

OBJECTIVE

To investigate the effect of glucose excursion on oxidative stress that is expressed by plasma 8-iso prostaglandin F2alpha (8-iso) level.

METHODS

Continuous glucose monitor system (CGMS) was used to calculate the mean amplitude of glycemic excursion (MAGE), mean blood glucose (MBG) and its standard deviation (SDBG), mean 1 h preprandial glucose value (1 h-prePG) and 3 h post-prandial glucose value (3 h PPG) over 24 h period, area under the ROC curve when the blood glucose within 24 h > 5.6 mmol/L (AUC 5.6), mean of daily differences (MODD), and mean postprandial glucose excursion (MPPGE) on 33 individuals with normal glucose regulation (NGR), 25 subjects with impaired glucose regulation (IGR), and 25 patients with newly diagnosed type 2 diabetes mellitus (T2DM) for 3 days. Plasma 8-iso level was determined by EIA.

RESULTS

The plasma 8-iso level of the T2DM patients was 230 ng/L, significantly higher than that of the subjects with IGR (199 ng/L, P < 0.05) and that of the NGR subjects (156 ng/L, P < 0.01). Patients with T2DM also had higher levels of glycated hemoglobin (HbA1c), MBG, SDBG, 1 h pre-PG and 3 h PPG, MAGE, and MODD than those of the NGR and IGR subjects (P < 0.05 or 0.01). The plasma 8-iso level and parameters of glucose excursion of the IGR subjects were all significantly higher than those of the NGR individuals (P < 0.05 or 0.01). Plasma 8-iso level was positively correlated with MAGE, MBG, SDBG, 1 h pre-PG, 3 h PPG, MODD, and HbA1c in all groups. Further analysis showed that the relationship between plasma 8-iso level and MAGE remained significant after adjustment for the other parameters of glucose excursion in multiple linear regression analysis (multiple R(2) = 0.55 for the model including MAGE). Standardized regression coefficients were 0.694 (P = 0.000) for MAGE.

CONCLUSION

Glucose excursion exhibits a stronger triggering effect on oxidative stress than chronic sustained hyperglycemia in the subjects with IGR and T2DM.

The effects of normoxic versus hyperoxic cardiopulmonary bypass on oxidative stress and inflammatory response in cyanotic pediatric patients undergoing open cardiac surgery: a randomized controlled trial

OBJECTIVES

This study investigates the effects of controlled reoxygenation cardiopulmonary bypass on oxidative stress, inflammatory response, and organ function in children undergoing repair of cyanotic congenital heart defects.

METHODS

Sixty-seven cyanotic patients (median age 15 months, interquartile range 6-49 months) undergoing corrective cardiac surgery were randomized to receive either controlled normoxic (50-0 mm Hg; n = 35) or hyperoxic (150-180 mm Hg; n = 32) cardiopulmonary bypass. Troponin I and 8-isoprostane, C3a, interleukins 6, 8, and 10, cortisol, protein S100, and alpha-glutamate transferase were measured preoperatively and 10 and 30 minutes after starting bypass, on removal of the aortic crossclamp, and 12 and 24 hours thereafter.

RESULTS

Overall, troponin I and 8-isoprostane levels were lower in the controlled normoxic group (-29%, 95% CI -48% to -3%, P = .03, and -26%, 95% CI -44% to -2%, P = .03, respectively). Protein S100 release was also lower in the normoxic group 10 minutes after starting bypass (-26%, 95% CI -40% to -9%, P = .005) and 10 minutes after aortic crossclamp removal (-23%, 95% CI -38% to -3%, P = .02, respectively), but similar at other time points in the two groups (P >or= .17). The alpha-glutamate transferase release was significantly lower in the normoxic group 10 minutes after aortic crossclamp removal (-28%, 95% CI -44% to -9%, P = .006, respectively) but was similar at other times (P >or= .11). Release of C3a, interleukins 6, 8, and 10, and cortisol was similar in the two groups throughout (P >or= .15).

CONCLUSION

Controlled reoxygenation on starting cardiopulmonary bypass is associated with reduced myocardial damage, oxidative stress, and cerebral and hepatic injury compared with hyperoxic bypass and similar whole body inflammatory and stress response in cyanotic children undergoing open cardiac surgery.

Effects of a phytosterol-enriched dairy product on lipids, sterols and 8-isoprostane in hypercholesterolemic patients: a multicenter Italian study

BACKGROUND AND AIMS

Plant sterols, added to several food sources, lower serum cholesterol concentrations. Plant sterol-induced cholesterol lowering is paralleled by a mild decrease in plasma levels of the antioxidant beta-carotene, the amount of this decrease being considered clinically non-significant. Whether the effect on lipid profile of daily consumption of plant sterol-enriched low-fat fermented milk (FM) is paralleled by a concomitant variation in a reliable marker of the oxidative burden like plasma isoprostane levels is unresolved.

METHODS AND RESULTS

The effect of plant sterol consumption on plasma lipid and isoprostane levels of hypercholesterolemic patients was evaluated in a multicenter, randomized double blind study. Hypercholesterolemic patients consumed a FM daily for 6 weeks. Subjects were randomized to receive either 1.6g of plant sterol-enriched FM (n=60) or control FM product (n=56). After 6 weeks of plant sterol-enriched FM consumption, LDL cholesterol was reduced from 166.2+/-2.0 to 147.4+/-2.8 mg/dL (p=0.01). A significant reduction was observed for total cholesterol (from 263.5+/-2.6 to 231.0+/-3.2mg/dL, p=0.01). There was greater LDL cholesterol lowering among hypercholesterolemic patients with higher LDL cholesterol at baseline. We found a reduction of plasma 8-isoprostane in patients taking plant sterol-enriched FM (from 43.07+/-1.78 to 38.04+/-1.14 pg/ml, p=0.018) but not in patients taking the control product (from 42.56+/-2.12 to 43.19+/-2.0 pg/ml, p=NS). Campesterol and beta-sitosterol levels were not influenced by phytosterol consumption.

CONCLUSIONS

Daily consumption of low-fat plant sterol dairy product favourably changes lipid profile by reducing LDL-cholesterol, and may also have an anti-oxidative effect through a reduction of plasma isoprostanes.

Boron deprivation decreases liver S-adenosylmethionine and spermidine and increases plasma homocysteine and cysteine in rats

Two experiments were conducted with weanling Sprague-Dawley rats to determine whether changes in S-adenosylmethionine utilization or metabolism contribute to the diverse responses to boron deprivation. In both experiments, four treatment groups of 15 male rats were fed ground corn-casein based diets that contained an average of 0.05 mg (experiment 1) or 0.15 mg (experiment 2) boron/kg. In experiment 2, some ground corn was replaced by sucrose and fructose to increase oxidative stress. The dietary variables were supplemental 0 (boron-deprived) or 3 (boron-adequate) mg boron/kg and different fat sources (can affect the response to boron) of 75 g corn oil/kg or 65 g fish (menhaden) oil/kg plus 10 linoleic acid/kg. When euthanized at age 20 (experiment 1) and 18 (experiment 2) weeks, rats fed the low-boron diet were considered boron-deprived because they had decreased boron concentrations in femur and kidney. Boron deprivation regardless of dietary oil increased plasma cysteine and homocysteine and decreased liver S-adenosylmethionine, S-adenosylhomocysteine, and spermidine. Plasma concentration of 8-iso-prostaglandin F2alpha (indicator of oxidative stress) was not affected by boron, but was decreased by feeding fish oil instead of corn oil. Fish oil instead of corn oil decreased S-adenosylmethionine, increased spermidine, and did not affect S-adenosylhomocysteine concentrations in liver. Additionally, fish oil versus corn oil did not affect plasma homocysteine in experiment 1, and slightly increased it in experiment 2. The findings suggest that boron is bioactive through affecting the formation or utilization of S-adenosylmethionine. Dietary fatty acid composition also affects S-adenosylmethionine formation or utilization, but apparently through a mechanism different from that of boron.

Expression of CREB-binding protein and peroxisome proliferator-activated receptor gamma during formoterol or formoterol and corticosteroid therapy of chronic obstructive pulmonary disease

We assessed the effect of therapy on nuclear signaling related to inflammatory processes in sputum cells of patients with chronic obstructive pulmonary disease (COPD). Patients were treated with formoterol (F) or formoterol plus budesonide (F/ICS) b.i.d. for 4 weeks, their sputum cells were isolated and subjected to RNA extraction or lysis, followed by differential centrifugation. Signaling protein levels were assessed by Western blots, their specific mRNAs were quantified using qRTPCR, while 8-isoprostane levels were examined using enzyme immunoassay kit. Cytosolic 8-isoprostane levels and nuclear glucocorticoid receptor expression (protein and mRNA) were not significantly different in both groups, while nuclear cAMP response element binding protein (CREB; protein and mRNA) and peroxisome proliferator-activated receptor gamma (PPARgamma protein and mRNA) were significantly higher in cells from F/ICS-treated patients. CREB-binding protein (CBP; protein and mRNA) levels were significantly lower in F/ICS patients. These changes indicate increased anti-inflammatory signaling in F/ICS-treated patients and seem to be beneficial.

Increased oxidative stress and astrogliosis responses in conditional double-knockout mice of Alzheimer-like presenilin-1 and presenilin-2

Conditional presenilin 1 and presenilin 2 double knockout causes memory dysfunction and reproduces neurodegenerative phenotypes of Alzheimer disease (AD) in mice. Oxidative stress has been long implicated predominantly in amyloidosis-mediated AD pathologies; however, its role in response to the loss-of-function pathogenic mechanism of AD remains unclear. In this study, we examined the oxidative stress status in PS1 and PS2 double-knockout (PS cDKO) mice using F(2)-isoprostanes (iPF(2alpha)-III) as the marker of lipid peroxidation. Lipid peroxidation was enhanced in a gender- and age-related manner in the PS cDKO mice independent of brain Abeta deposition. Such oxidative abnormalities predominantly in cerebral cortex at 2-4 months of age preceded the onset of many pronounced AD neuropathologies, suggesting that increased lipid peroxidation is not only an early pathophysiological response to PS inactivation, but also a potential culprit responsible for the AD-like neurodegenerative pathologies in the PS cDKO mice. Western blot analysis of cortical glial fibrillary acidic protein demonstrated an increased astrogliosis response to PS inactivation, in particular in the PS cDKO mice at as young as 2 months of age, suggesting that lipid peroxidation and neuronal injury may be closely associated with the loss-of-function neuropathogenic mechanism of AD.

ETA receptor blockade attenuates hypertension and decreases reactive oxygen species in ETB receptor-deficient rats

We hypothesize that endothelin-A receptor stimulation contributes to the elevated blood pressure and superoxide production in endothelin-B receptor-deficient rats on a high salt diet. Experiments were conducted on homozygous endothelin-B-deficient (sl/sl) and wild-type rats (wt) fed a high salt diet (8% NaCl) for 3 weeks. Separate groups were given normal drinking water or water containing the endothelin-A receptor antagonist, ABT-627 (5 mg/kg per day; n = 8-9 in all groups). On a normal salt diet, (sl/sl) rats had a significantly elevated systolic blood pressure compared with wt (138 +/- 3 vs 117 +/- 4 mmHg, respectively; P < 0.05). High salt diet caused a significant increase in systolic blood pressure in (sl/sl) rats compared with wt (158 +/- 2 vs 138 +/- 3 mmHg, respectively; P < 0.05). Endothelin-A receptor blockade decreased systolic blood pressure in (sl/sl) rats on high salt (125 +/- 5 mmHg; P < 0.05 vs without antagonist) without affecting the systolic blood pressure in wt (119 +/- 4 mmHg). Aortic superoxide production (lucigenin chemiluminescence) and plasma 8-isoprostane were elevated in sl/sl rats and were significantly reduced by endothelin-A receptor blockade in sl/sl, but not in wt rats. These findings suggest that endothelin-1, through the endothelin-A receptor, contributes to salt-induced hypertension and vascular superoxide production in endothelin-B-deficient rats.