Reactive Oxidative Metabolites Research Articles

Anthocyanins attenuate vascular and inflammatory responses to a high fat high energy meal challenge in overweight older adults: A cross-over, randomised, double-blind clinical trial

Postprandial metabolic imbalances are important indicators of later developing cardiovascular disease (CVD)(1). This study investigated the effects of food anthocyanins on vascular and microvascular function, and CVD associated biomarkers following a high fat high energy (HFHE) meal challenge in overweight older adults. Sixteen subjects (13 female, 3 male, mean age 65.9 SD 6.0 and body mass index 30.6 kg/m 2 SD 3.9) participated in a crossover, randomised, controlled, double-blind clinical trial (Australian New Zealand Clinical Trials Registry # ACTRN12620000437965). Participants consumed a HFHE breakfast meal (65g total fat; 33g saturated fat) together with a 250 mL dose of either intervention (Queen Garnet Plum providing 201 mg anthocyanins) or control (apricot) juice. A wash-out period of 14 days occurred between meal challenges, with a 4-day run-in period for juice consumption before each challenge. Blood samples and blood pressure measures were collected at baseline, 2 h and 4 h following the HFHE meal. Vascular function, assessed using flow mediated dilatation (FMD), and microvascular cutaneous vascular reactivity, measured using Laser Speckle Contrast Imaging (LSCI), were evaluated at baseline and 2 h after the HFHE meal. Participants had a higher 2 h postprandial FMD (+1.14%) and a higher microvascular post-occlusive reactive hyperaemia (+0.10 perfusion units per mmHg) when allocated to the anthocyanin compared to the control arm (P = 0.019 and P = 0.049, respectively). C-reactive protein was lower 4 h postprandially in the anthocyanins (1.80 mg/L, IQR 0.90) vs control arm (2.30 mg/L, IQR 1.95) (P = 0.026), accompanied by a trend for lower concentrations of interleukin-6 (P = 0.075). No significant postprandial differences were observed between treatments for blood pressure, triacylglycerol, total cholesterol, serum derivatives of reactive oxidative metabolites, tumor necrosis factor α, interleukin-1 β, or maximum microvascular perfusion following iontophoresis of acetylcholine. Fruit-based anthocyanins attenuated the potential postprandial detrimental effects of a HFHE challenge on parameters of vascular and microvascular function, and inflammatory biomarkers in overweight older adults. Anthocyanins may reduce cardiovascular risk associated with endothelial dysfunction and inflammatory responses to a typical high fat ‘Western’ meal.

Myeloperoxidase, carnitine, and derivatives of reactive oxidative metabolites in heart failure with preserved versus reduced ejection fraction: A meta-analysis

BackgroundUnderstanding the pathophysiology of heart failure (HF) with preserved ejection fraction (HFpEF) continues to be challenging. Several inflammatory and metabolic biomarkers have recently been suggested to be involved in HFpEF. ObjectivesThe purpose of this review was to synthesize the evidence on non-traditional biomarkers from metabolomic studies that may distinguish HFpEF from heart failure with reduced ejection fraction (HFrEF) and controls without HF. MethodsA systematic search was conducted using Medline and PubMed with search terms such as “HFpEF” and “metabolomics”, and a meta-analysis was conducted. ResultsMyeloperoxidase (MPO) levels were significantly (p < 0.001) higher in HFpEF than controls without HF, but comparable (p = 0.838) between HFpEF and HFrEF. Carnitine levels were significantly (p < 0.0001) higher in HFrEF than HFpEF, but comparable (p = 0.443) between HFpEF and controls without HF. Derivatives of reactive oxidative metabolites (DROMs) were not significantly (p = 0.575) higher in HFpEF than controls without HF. ConclusionThese data suggest that MPO is operative in HFpEF and HFrEF and may be a biomarker for HF. Furthermore, circulating carnitine levels may distinguish HFrEF from HFpEF.

Longitudinal characterization of the metabolome of dairy cows transitioning from one lactation to the next: Investigations in blood serum

The objective of this study was to characterize changes in the serum metabolome and various indicators of oxidative balance in dairy cows starting 2 wk before dry-off and continuing until wk 16 of lactation. Twelve Holstein dairy cows (body weight 745 ± 71 kg, body condition score 3.43 ± 0.66; mean ± SD) were housed in a tiestall barn from 10 wk before to 16 wk after parturition. Cows were dried off 6 wk before the expected calving date (mean dry period length = 42 d). From 8 wk before calving to 16 wk after calving, blood samples were taken weekly to study redox metabolism by determining antioxidant capacity, measured as the ferric-reducing ability of plasma, reactive oxidative metabolites, oxidative stress index, oxidative damage of lipids, measured as thiobarbituric acid reactive substances, and glutathione peroxidase activity. According to these results, dairy cows had the lowest serum antioxidant capacity and greater levels of oxidative stress during the dry-off period and the early postpartum period. For metabolomics, a subset of serum samples including wk -7 (before dry-off), -5 (after dry-off), -1, 1, 5, 10, and 15 relative to calving were used. A targeted metabolomics approach was performed using liquid chromatography and flow injection with electrospray ionization triple quadrupole mass spectrometry using the MxP Quant 500 kit (Biocrates Life Sciences AG). A total of 240 metabolites in serum were used in the final data analysis. Principal component analysis revealed a clear separation by days of sampling, indicating a remarkable shift in metabolic phenotype between the dry period and late and early lactation. Changes in many non-lipid metabolites associated with one-carbon metabolism, the tricarboxylic acid cycle, the urea cycle, and AA catabolism were observed in the study, with changes in AA serum concentrations likely related to factors such as energy and nitrogen balance, digestive efficiency, and changing diets. The study confirmed an extensive remodeling of the serum lipidome in peripartum dairy cows, highlighting the importance of changes in acylcarnitine (acylCN), phosphatidylcholines (PC), and triacylglycerols (TG), as they play a crucial role in lipid metabolism. Results showed that short-chain acylCN increased after dry-off and decreased thereafter, whereas lipid-derived acylCN increased around parturition, suggesting that more fatty acids could enter mitochondria. Phospholipids and sphingolipids in serum showed changes during lactation. In particular, concentrations of sphingomyelins, PC, and lysoPC decreased around calving but increased in mid- and late lactation. In contrast, concentrations of TG remained consistently low after parturition. The serum concentrations of bile acids fluctuated during the dry period and lactation, with glycocholic acid, cholic acid, glycodeoxycholic acid, and taurocholic acid showing the greatest concentrations. These changes are likely due to the interplay of diet, liver function, and the ability of the gut microbiota to convert primary to secondary bile acids. Overall, these descriptive results may aid in hypothesis generation and in the design and interpretation of future metabolite-based studies in dairy cows. Furthermore, they contribute to our understanding of the physiological ranges in serum metabolites relative to the lactation cycle of the dairy cow.

Feeding spent hemp biomass to lactating dairy cows: Effects on performance, milk components and quality, blood parameters, and nitrogen metabolism

The legalization of industrial hemp by the 2018 Farm Bill in the United States has driven a sharp increase in its cultivation, including for cannabinoid extraction. Spent hemp biomass (SHB), produced from the extraction of cannabinoids, can potentially be used as feed for dairy cows; however, it is still illegal to do so in the United States, according to the US Food and Drug Administration Center for Veterinary Medicine, due to the presence of cannabinoids and the lack of data on the effect on animals. To assess the safety of this byproduct as feed for dairy cows, late-lactation Jersey cows (245 ± 37 d in milk; 483 ± 38 kg body weight; 10 multiparous and 8 primiparous) received a basal total mixed ration (TMR) diet plus 13% alfalfa pellet (CON) or 13% pelleted SHB for 4 wk (intervention period [IP]) followed by 4 wk of withdrawal period (WP), where all cows received only the basal TMR during WP. The dry matter intake (DMI), body weight, body condition score, milk yield, milk components, and fatty acid profile, blood parameters, N metabolism, methane emission, and activity were measured. Results indicated that feeding SHB decreased DMI mainly due to the low palatability of the SHB pellet, as the cows consumed only 7.4% of the total TMR with 13.0% SHB pellet offered in the ration. However, milk yield was not affected during the IP and was higher than CON during the WP, leading to higher milk yield/DMI. Milk components were not affected, except for a tendency in decreased fat percentage. Milk fat produced by cows fed SHB had a higher proportion of oleate and bacteria-derived fatty acids than CON. The activity of the cows was not affected, except for a shorter overall lying time in SHB versus CON cows during the IP. Blood parameters related to immune function were not affected. Compared with CON, cows fed SHB had a lower cholesterol concentration during the whole experiment and higher β-hydroxybutyric acid during the WP, while a likely low-grade inflammation during the IP was indicated by higher ceruloplasmin and reactive oxidative metabolites. Other parameters related to liver health and inflammatory response were unaffected, except for a tendency for higher activity of alkaline phosphatase during IP and a lower activity of gamma-glutamyl transferase during WP in the SHB group versus CON. The bilirubin concentration was increased in cows fed SHB, suggesting a possible decrease in the clearance ability of the liver. Digestibility of the dry matter and protein and methane emission were not affected by feeding SHB. The urea, purine derivatives, and creatinine concentration in urine was unaffected, but cows fed SHB had higher N use efficiency and lower urine volume. Altogether, our data revealed a relatively low palatability of SHB affecting DMI with minimal biological effects, except for a likely low-grade inflammation, a higher N use efficiency, and a possible decrease in liver clearance. Overall, the data support the use of SHB as a safe feed ingredient for lactating dairy cows.

Using available in vitro metabolite identification and time course kinetics for β-chloroprene and its metabolite, (1-chloroethenyl) oxirane, to include reactive oxidative metabolites and glutathione depletion in a PBPK model for β-chloroprene.

Introduction: ß-chloroprene (2-chloro-1,3-butadiene; CP) causes lung tumors after inhalation exposures in rats and mice. Mice develop these tumors at lower exposures than rats. In rats CP exposures cause depletion of lung glutathione (GSH). Methods: PBPK models developed to relate the appearance of mouse lung tumors with rates of CP metabolism to reactive metabolites or total amounts metabolized during exposures have been expanded to include production of reactive metabolites from CP. The extended PBPK model describes both the unstable oxirane metabolite, 2-CEO, and metabolism of the more stable oxirane, 1-CEO, to reactive metabolites via microsomal oxidation to a diepoxide, and linked production of these metabolites to a PK model predicting GSH depletion with increasing CP exposure. Key information required to develop the model were available from literature studies identifying: 1) microsomal metabolites of CP, and 2) in vitro rates of clearance of CP and 1-CEO from active microsomal preparations from mice, rats, hamsters and humans. Results: Model simulation of concentration dependence of disproportionate increases in reactive metabolite concentrations as exposures increases and decreases in tissue GSH are consistent with the dose-dependence of tumor formation. At the middle bioassay concentrations with a lung tumor incidence, the predicted tissue GSH is less than 50% background. These simulations of reduction in GSH are also consistent with the gene expression results showing the most sensitive pathways are Nrf2-regulation of oxidative stress and GSH metabolism. Discussion: The PBPK model is used to correlate predicted tissue exposure to reactive metabolites with toxicity and carcinogenicity of CP.

Disturbed Antioxidant Capacity in Patients with Systemic Sclerosis Associates with Lung and Gastrointestinal Symptoms.

The correct balance between reactive oxygen species and antioxidant defense in an organism is disturbed in oxidative stress. To assess oxidative balance in 36 SSc patients and 26 healthy controls (HCs), we measured reactive oxidative metabolites (ROMs), total antioxidant capacity (TAC), lipid peroxidation (measuring 4-HNE), and DNA oxidative damage (measuring 8-OHdG) in serum. Furthermore, DNA breaks in leukocytes of 35 SSc patients and 32 HCs were evaluated using COMET. While we report high ROMs for both SSc patients and age/sex matched HC samples, there was a significant increase in TAC in SSc patients as compared to HCs, and thus also a significantly higher oxidative stress index in SSc patients. TAC was significantly higher in SSc patients with ILD and gastrointestinal involvement, as well as in patients with anti-topoisomerase antibodies. We observe no difference in serum lipid peroxidation status or oxidative DNA damage. However, SSc patients had significantly more leukocyte DNA breaks than HCs; the most damage was observed in patients treated with immunosuppressives. Thus, our study confirms presence of oxidative stress and increased DNA damage in leukocytes of SSc patients; however, it points toward increased antioxidant capacity, which needs to be further studied.

Oxidative Stress and High-Mobility Group Box 1 Assay in Dogs with Gastrointestinal Parasites.

This study aimed to evaluate the concentration of reactive oxidative metabolites, the antioxidant barrier, thiol groups of plasma compounds, and high-mobility group box 1 in shelter dogs naturally infected with helminths. In addition, the correlation between clinical signs and oxidative stress was investigated. Sixty-six (41 male and 25 female) adult mixed-breed dogs housed in a shelter with the diagnosis of gastrointestinal nematodes (i.e., Ancylostoma spp., Uncinaria stenocephala, Toxocara canis, Toxascaris leonina, or Trichuris vulpis) were enrolled in Group 1 (G1) and twenty healthy adult dogs were included in Group 2 (G2), which served as the control. A clinical assessment was performed using a physician-based scoring system. Oxidative stress variables and high-mobility group box 1 were assessed and compared by the means of unpaired t-tests (p < 0.05). Spearman’s rank correlation was performed to calculate the correlation between oxidative stress variables, high-mobility group box 1, hematological parameters, and clinical signs. The results showed statistically significant values for reactive oxidative metabolites, thiol groups of plasma compounds, and high-mobility group box 1 in G1. Negative correlations between thiol groups and the number of red cells and hemoglobin were recorded. These preliminary results support the potential role of oxidative stress and HGMB-1 in the pathogenesis of gastrointestinal helminthiasis in dogs.

Effectiveness of the d-ROMs oxidative stress test to predict long-term cardiovascular mortality

BackgroundThe long-term prognostic value of the derivatives of reactive oxidative metabolites (d-ROMs) oxidative stress test, which measures hydroperoxide in blood, has not been fully investigated. Methods and resultsWe administered the d-ROMs test to 265 patients with cardiovascular disease (204 men, 61 women; age, 65 ± 13 years) and followed these patients for up to 10 years. During the observational period of 5.82 (2.47–8.34) years, 31 (12%) patients died, including 20 (8%) of cardiovascular death, and 33 (12%) had major adverse cardiovascular events (MACEs). Cox regression analysis revealed that patients with a d-ROMs value ≥395 U.CARR had a greater risk for all-cause mortality [unadjusted hazard ratio (95% confidence interval), 3.586 (1.772–7.257)], cardiovascular death [7.034 (2.805–17.640)], and MACEs [4.440 (2.237–8.814)] (p < 0.001 for all). In a model adjusted for age, sex, estimated glomerular filtration rate, C-reactive protein, diabetes, hypertension, hyperlipidemia, coronary artery diseases, current smoking, and log-transformed brain natriuretic peptide, all-cause death [2.311 (1.059–5.135), p = 0.036], cardiovascular death [4.398 (1.599–12.099), p = 0.004], MACEs [2.696 (1.266–5.739), p = 0.010] were still significant in patients with high d-ROMS values. ConclusionA high d-ROMs value is an independent predictor of the long-term risk of cardiovascular mortality. A d-ROMs value of 395 U.CARR was considered to be an appropriate threshold for distinguishing prognosis.

Oxidative Stress Evaluation in Dogs Affected with Canine Monocytic Ehrlichiosis.

The study aimed to evaluate the concentration of reactive oxidative metabolites (R-OOHs), the antioxidant barrier (OXY), and the ratio between R-OOHs and OXY (OSi) and thiol groups of plasma compounds (SHp) in in canine monocytic ehrlichiosis. Thirty dogs affected with monocytic ehrlichiosis (canine monocytic ehrlichiosis group—CME group) and ten healthy dogs (control group—CTR group) were evaluated. CME was diagnosed by the presence of clinical signs and the detection of anti-Ehlichia canis antibodies. Oxidative stress parameters of two groups were compared using the Mann–Whitney test. Significance was set at p < 0.05. Spearman rank correlation was performed to analyze oxidative stress, and hematological and biochemical variables in the CME group. All dogs affected with CME showed a wide spectrum of clinical signs such as lethargy, anorexia, fever, weight loss, lymph adenomegaly, splenomegaly, subcutaneous and mucosal petechial and ecchymosis, and vomiting. Anaemia, leukocytosis, thrombocytopenia, hyperglobulinemia, hypoalbuminemia and an increase of blood urea nitrogen and creatinine are also detected. Results showed significantly lower values of SHp in the CME group than in CTR. A statistically significant difference in the number of white blood cells, platelets, and blood urea nitrogen concentration was assayed comparing to the two groups. A negative correlation between SHp and hemoglobin concentration was recorded. These preliminary results may suggest a possible function of oxidative stress in the onset of clinical signs during the course of CME.

Correlation between Severity of Fetal Growth Restriction and Oxidative Stress in Severe Small-for-Gestational-Age Infants.

Severe small-for-gestational-age (sSGA) infants exhibit increased mortality and morbidity. Oxidative stress is suggested to be involved in intrauterine growth restriction. This retrospective study aimed to evaluate the oxidative stress level at birth in an sSGA population. Sera of 28 sSGA (sSGA group) and 31 non-sSGA (control group) infants, born at our hospital between March 2017 and March 2020, were evaluated. Oxidative stress (derivative of reactive oxidative metabolites: d-ROM level), biological antioxidant potential (BAP) level, and the ratio of d-ROM/BAP level (oxidative stress index: OSI) were measured. The sSGA group had a significantly lower birth weight (BW), BW z-score, head circumference, and height than the control group (all p < 0.05). No significant difference was noted in the BAP level; sSGA infants exhibited a significantly higher d-ROM level than control infants. sSGA infants showed a significantly increased OSI compared with control infants, and the BW z-score was inversely correlated with d-ROM levels and OSI in sSGA infants (R2 = 0.300; p < 0.01 and R2 = 0.319; p = 0.02, respectively) but not in controls. In conclusion, sSGA infants, including preterm infants, exhibited higher oxidative stress at birth. The severity of fetal growth restriction was significantly correlated with oxidative stress levels at birth in sSGA infants.

Characteristics of the Oxidative Status in Dairy Calves Fed at Different Milk Replacer Levels and Weaned at 14 Weeks of Age

A paradigm shift in the way of rearing heifer calves from restricted feeding and early weaning towards greater feed allowances and later weaning ages is ongoing. We aimed at characterizing the oxidative status in Holstein heifer calves fed with milk replacer (MR) at either a restrictive (RES) or a high (HIGH) level for 14 weeks. We compared two groups: HIGH (10 L MR/d, n = 18) and RES (5.7 L/d, n = 19) from day five until week 14 of life. In blood samples collected at birth, and then fortnightly from week 8–16, and in week 20, the antioxidative capacity measured as ferric reducing ability of plasma (FRAP), oxidative damage of lipids measured as thiobarbituric acid reactive substances (TBARS) and oxidative damage of proteins measured as advanced oxidation products of proteins (AOPP), free radicals measured as reactive oxidative metabolites (dROM), and the glutathione peroxidase (GSH-Px) activity, as well as leptin, adiponectin and haptoglobin were assessed. The time course of these variables during the first 20 weeks of life showed characteristic patterns; group differences were limited to adiponectin, AOPP, and FRAP. RES calves had lower growth rates, showed signs of hunger, but did not differ from HIGH in their intake of solid starter feed and in health status. This work characterizes the changes in oxidative status of dairy calves with increasing age and confirms the benefits of a high feeding plane with regard to welfare and development.

Anthocyanins attenuate vascular and inflammatory responses to a high fat high energy meal challenge in overweight older adults: A cross-over, randomized, double-blind clinical trial

Postprandial metabolic imbalances are important indicators of later developing cardiovascular disease (CVD). This study investigated the effects of food anthocyanins on vascular and microvascular function, and CVD associated biomarkers following a high fat high energy (HFHE) meal challenge in overweight older adults. Sixteen subjects (13 female, 3 male, mean age 65.9 SD 6.0 and body mass index 30.6kg/m2 SD 3.9) participated in a crossover, randomized, controlled, double-blind clinical trial (registered under Australian New Zealand Clinical Trials Registry, identifier no. ACTRN12620000437965). Participants consumed a HFHE meal with a 250mL dose of either intervention (anthocyanins-rich Queen Garnet Plum) or control (apricot) juice. Blood samples and blood pressure measures were collected at baseline, 2h and 4h following the HFHE meal. Vascular and microvascular function were evaluated at baseline and 2h after the HFHE meal. Participants had a higher 2h postprandial flow-mediated dilatation (+1.14%) and a higher microvascular post-occlusive reactive hyperaemia (+0.10 perfusion units per mmHg) when allocated to the anthocyanin compared to the control arm (P=0.019 and P=0.049, respectively). C-reactive protein was lower 4h postprandially in the anthocyanins (1.80mg/L, IQR 0.90) vs control arm (2.30mg/L, IQR 1.95) (P=0.026), accompanied by a trend for lower concentrations of interleukin-6 (P=0.075). No significant postprandial differences were observed between treatments for blood pressure, triacylglycerol, total cholesterol, serum derivatives of reactive oxidative metabolites, tumor necrosis factor alpha, interleukin-1 beta, or maximum microvascular perfusion following iontophoresis of acetylcholine. Fruit-based anthocyanins attenuated the potential postprandial detrimental effects of a HFHE challenge on parameters of vascular and microvascular function, and inflammatory biomarkers in overweight older adults. Anthocyanins may reduce cardiovascular risk associated with endothelial dysfunction and inflammatory responses to a typical high fat 'Western' meal. Further studies are required to better elucidate the clinical implications of postprandial biomarkers of CVD.

Clinical significance of reactive oxidative metabolites in patients with heart failure with reduced left ventricular ejection fraction

We investigated the clinical significance of the derivative of reactive oxygen metabolites (DROM), a new marker of reactive oxygen species (ROS), in patients with heart failure (HF) with reduced left ventricular ejection fraction (LVEF) (HFrEF). Serum DROM concentrations were measured in 201 consecutive patients with HFrEF (EF < 50%) in stable condition. DROM values were significantly higher in patients with HFrEF than in risk-matched patients without HF (P < 0.01). They also correlated significantly with high-sensitivity C-reactive protein and B-type natriuretic peptide. Kaplan-Meier analysis demonstrated significantly higher probabilities of HF-related events in the high-DROM group than in the low-DROM group (log-rank test, P < 0.01). Multivariable Cox hazard analysis revealed that DROM were independent and significant predictors of cardiovascular events. In a subgroup analysis, DROM levels were also measured at the aortic root and coronary sinus in 49 patients. The transcardiac gradient of DROM values was significantly higher in patients with HFrEF than in patients without HF (P = 0.04), indicating an association between DROM production in the coronary circulation and HFrEF development. Changes in DROM following optimal therapy were significantly associated with LVEF improvement (r = 0.34, P = 0.04). The higher levels of DROM and their association with cardiovascular events suggest the clinical benefit of DROM measurements in the risk stratification of patients with HFrEF.

Formation primaquine-5,6-orthoquinone, the putative active and toxic metabolite of primaquine via direct oxidation in human erythrocytes

BackgroundThe activity and haemolytic toxicity associated with primaquine has been linked to its reactive metabolites. The reactive metabolites are thought to be primarily formed through the action of cytochrome P450-mediated pathways. Human erythrocytes generally are not considered a significant contributor to drug biotransformation. As erythrocytes are the target of primaquine toxicity, the ability of erythrocytes to mediate the formation of reactive oxidative primaquine metabolites in the absence of hepatic enzymes, was evaluated.MethodsPrimaquine and its enantiomers were incubated separately with human red blood cells and haemoglobin. Post-incubation analysis was performed with UPLC–MS/MS to identify products of biotransformation.ResultsThe major metabolite detected was identified as primaquine-5,6-orthoquinone, reflecting the pathway yielding putative active and haematotoxic metabolites of primaquine, which was formed by oxidative demethylation of 5-hydroxyprimaquine. Incubation of primaquine with haemoglobin in a cell-free system yielded similar results. It appears that the observed biotransformation is due to non-enzymatic processes, perhaps due to reactive oxygen species (ROS) present in erythrocytes or in the haemoglobin incubates.ConclusionThis study presents new evidence that primaquine-5,6-orthoquinone, the metabolite of primaquine reflecting the oxidative biotransformation pathway, is generated in erythrocytes, probably by non-enzymatic means, and may not require transport from the liver or other tissues.

ADMA, homocysteine and redox status improvement affected by 7-nitroindazole in spontaneously hypertensive rats

Inhibition of nitric oxide (NO) production can influence blood pressure regulation and increase hypertension. Asymmetric dimethylarginine, ADMA, an analogue of L-arginine, can inhibit NO synthesis, impair endothelial function, and is a risk marker of cardiovascular diseases. Homocysteine (Hcy) level affects oxidative stress production of reactive oxygen species (ROS) in hypertension and also influences changes in signaling and cell damage.The present study was focused on experimental effects of exogenous NOS inhibitors and their effect on ADMA, an endogenous NOS inhibitor, homocysteine and ROS production measured as reactive oxidative metabolites (ROM). We compared effects of the two potential exogenous NO-inhibitors: NG-nitro L-arginine methyl ester (L-NAME) and 7-nitroindazole (7-NI). Levels of ADMA, Hcy, ROM and total thiols (TTL) were not changed in the L-NAME group. With 7-NI administration, we observed unchanged NOS activity in the left ventricle and a pronounced decrease of ADMA and Hcy levels, accompanied by ROM over-production in plasma. TTL/ROM ratio was more favorable than in the L-NAME group.We observed that 7-NI, an exogenous NOinhibitor, can decrease and improve the levels of ADMA, Hcy, and ROM, and increase TTL/ROM ratio in the plasma of spontaneously hypertensive rats.

Abstract 11614: The Clinical Significance and Novel Mechanism of Reactive Oxygen Species in Heart Failure With Preserved Left Ventricular Ejection Fraction

Introduction: By performing basic and clinical researches, we investigated the clinical significance of reactive oxygen species (ROS) biomarker and the mechanism of ROS production in heart failure with preserved left ventricular ejection fraction (HFpEF). Methods and Results: (1) We measured derivatives of reactive oxidative metabolites (DROM), new biomarker of ROS, in 287 HFpEF patients, and followed them. DROM was significantly higher in HFpEF patients compared to risk factor matched non-HF patients (p&lt;0.001), and was associated with the severity of HF (p&lt;0.001). Kaplan-Meier analysis demonstrated higher probability of cardiovascular events in high-DROM than low-DROM group (p=0.01). Multivariate Cox hazard analysis identified ln-DROM as independent predictor for cardiovascular events (p=0.04). (2) We examined the association of ROS with galectin-3, a predictor of cardiovascular events in HFpEF, by using angiotensin II (AII) receptor blocker (ARB) and galectin-3-inhibitor (Gal3-i) administrated Dahl salt-sensitive rats (DS rats), useful model of HFpEF. Increased left ventricular (LV) galectin-3 protein expressions by Western blotting in HFpEF DS rats were inhibited by ARB, indicating AII-induced galectin-3 expression in HFpEF. Furthermore, Gal3-i significantly reversed LV hypertrophy in DS rats suffered HFpEF (p=0.02), accompanied by the tendency of reduction in collagen-related mRNA gene expression (collagen-I, -III and MMP-2) by real-time RT-PCR. Serum DROM and LV mRNA gene expressions of subunits of ROS generative NADPH oxidase (p22 phox and NOX-2) were increased in HFpEF rats, and Gal3-i tended to downregulate them. These indicated AII induced galectin-3 is involved in LV fibrosis via ROS. (3) Galectin-3 at coronary sinus was higher than at aortic root in HFpEF patients, but not different in non-HF, indicating galectin-3 production in coronary circulation in HFpEF. Moreover, Kaplan-Meier analysis demonstrated higher probability of cardiovascular events in plasma high galectin-3 than in low galectin-3 group in HFpEF patients (p&lt;0.05), indicating clinical significance of galectin-3. Conclusions: These studies demonstrated clinical significance and novel mechanism of ROS in HFpEF.

Association of Circulating Follistatin-Like 1 Levels with Inflammatory and Oxidative Stress Markers in Healthy Men.

ObjectivesFollistatin-like 1 (Fstl1) is a circulating glycoprotein that plays a crucial role in cardiovascular diseases and inflammation-related disorders. We have shown that Fstl1 acts as an anti-inflammatory factor that protects against ischemic heart disease and chronic kidney disease. Here we examined whether plasma level of Fstl1 associates with markers of inflammation and oxidative stress in apparently healthy Japanese men.Methods and ResultsPlasma Fstl1 levels were measured by enzyme-linked immunosorbent assay. Circulating Fstl1 concentrations positively correlated with levels of fasting immune-reactive insulin (FIRI), high-sensitive CRP (hsCRP) and derivatives of reactive oxidative metabolites (dROMs), an indicator of oxidative stress. The levels of hsCRP positively associated with Fstl1, body mass index (BMI), triglyceride, FIRI and dROMs levels. dROMs levels positively associated with Fstl1, Hemoglobin A1c and hsCRP levels. Multiple regression analysis with confounding factors revealed that Fstl1 levels, together with BMI and FIRI, correlated with hsCRP and that Fstl1 levels correlated with dROMs.ConclusionOur observations indicate that measurement of plasma Fstl1 levels can be valuable for assessment of pro-inflammatory and oxidative stress conditions.

Evaluation of plasma reactive oxygen metabolites levels in obese subjects with periodontal disease.

Obesity represents the systemic condition capable of influencing the onset and progression of periodontal disease. Obesity is associated with oxidative stress. Plasma level of reactive oxidative metabolites (ROMs) is measured as an indicator of oxidative stress in the body. The aim of this study is to assess and compare the plasma ROM levels in obese subjects with healthy and inflammatory periodontal status. Sixty subjects selected were grouped as 15 obese or overweight subjects with generalized chronic periodontitis, 15 obese or overweight subjects with generalized chronic gingivitis, 15 obese or overweight subjects with healthy periodontium, and 15 nonobese and healthy periodontium. The clinical periodontal parameters such as plaque index, gingival index, probing pocket depth, and clinical attachment level were measured. Blood samples were obtained to measure the plasma levels of ROM. In this study, obese subjects with chronic periodontitis (Group I) had mean plasma ROM levels (442.3 ± 15.65 Carratelli unit [CARR U]) showing 100% subjects with high oxidative stress. Obese subjects with chronic gingivitis (Group II) had mean plasma ROM levels (358.7 ± 20.61 CARR U) indicating 86.7% subjects with oxidative stress. Obese subjects with healthy periodontium (Group III) had 46.7% subjects with slight oxidative stress, and the mean ROM level was 320.2 ± 17.57. Nonobese subjects with healthy periodontium (Group IV) had 80% of subjects with normal oxidative stress and the mean plasma ROM level was 296.9 ± 20.35 CARR U. The intra- and inter-group comparison showed significant difference (P < 0.001). From our study, we report that obese subjects with periodontitis have more oxidative stress compared to obese subjects with healthy periodontium.

Abstract 10036: Olmesartan Improves Not Only Vascular Endothelial Dysfunction but Cardiac Diastolic Dysfunction in Hypertensive Heart Failure With Preserved Ejection Fraction - ORION Study

Introduction: The optimal treatment for heart failure (HF) with preserved left ventricular (LV) ejection fraction (EF) (HFpEF) has not been established. Using an experimental model of HFpEF, we previously reported a novel mechanism underlying reversal of endothelial dysfunction and HFpEF by AT1 receptor blocker (ARB). By performing this study (ORION: OlmesaRtan Improvement endothelial functiON with hypertension study), we examined the effects of ARB on hypertensive HFpEF patients, focusing on reactive oxygen species (ROS). Methods and Results: We examined prospectively 20 hypertensive HFpEF patients, taking any renin-angiotensin system inhibitors, switched to appreciable amounts of highly-selective ARB; olmesartan (average dosage amounts: 22.9 mg/day) for 3 months. Despite no additive hypotensive effects of olmesartan, endothelial dysfunction assessed by fingertrip digital reactive hyperemia (RH) peripheral arterial tonometry using Endo-PAT2000 was significantly reversed (RH-index; 1.57±0.34 to 1.87±0.50, P=0.034), accompanied by significant reduction of serum derivatives of reactive oxidative metabolites levels, novel biomarker of ROS (362.8±13.7 to 302.1±9.4 unit called the Carratelli unit [U.CARR], P=0.001). Olmesartan treatments significantly improved cardiac diastolic function evaluated by the ratio of early transmitral flow velocity to tissue doppler early diastolic mitral annular velocity (15.4 to 11.0, P&lt;0.001) but not LVEF and LV anterior wall thickness in echocardiography, and decreased plasma B-type natriuretic peptide levels (214.9 to 191.4, P&lt;0.05) in HFpEF patients. Additionaly, olmesartan significantly increased plasma superoxide dismutase activity (2.39±0.73 to 3.06±0.78 U/mL, P=0.02) and adiponectin levels (2.66±1.55 to 4.12±1.99 μg/mL, P&lt;0.05), but not affect plasma nitrates and nitrites (NO3-/NO2-) levels (53.2±28.1 to 62.9±28.4 μmol/L). Conclusions: These data suggested that strong AT1 receptor blockade by olmesartan restored not only endothelial dysfunction but cardiac diastolic dysfunction in HFpEF beyond hypotensive effects. Increased in SOD activities and adiponectin levels, but not nitric oxide levels, might contribute to these beneficial effects of olmesartan.

The clinical significance of plasma neopterin in heart failure with preserved left ventricular ejection fraction.

AimsAlthough inflammation plays an important role in the pathogenesis of heart failure (HF), the precise pathophysiological role of inflammation in HF with preserved left ventricular ejection fraction (HFpEF) still remains unclear. Hence, we examined the clinical significance of plasma neopterin, an inflammatory biomarker, in HFpEF patients.Methods and resultsIn the present study, we recruited consecutive HFpEF patients hospitalized in Kumamoto University Hospital, and further measured plasma neopterin by high‐performance liquid chromatography and serum derivatives of reactive oxidative metabolites (DROM), a new biomarker of reactive oxygen species. Compared with risk factors (number of patients, age, sex, and equal incidence of diabetes mellitus, hypertension, and dyslipidemia) ‐matched non‐HF patients (n = 68), plasma neopterin levels, but not serum high‐sensitivity C‐reactive protein levels, were significantly increased in patients with HFpEF (n = 68) (P < 0.001 and P = 0.15, respectively), accompanied by an elevation in serum DROM levels (P < 0.001). Plasma neopterin levels in New York Heart Association (NYHA) class III/IV HFpEF patients were significantly higher than in NYHA class II patients (P < 0.004). Furthermore, plasma ln‐neopterin levels had significant and positive correlation with ln‐DROM values (r = 0.57) and parameters of cardiac diastolic dysfunction [the ratio of early transmitral flow velocity to tissue Doppler early diastolic mitral annular velocity (r = 0.34), left atrial volume index (r = 0.17), and B‐type natriuretic peptide (r = 0.38)]. Kaplan–Meier analysis showed that the high‐neopterin group (>51.5 nM: median value of neopterin in HFpEF patients) had a higher probability of cardiovascular events than the low‐neopterin group (log‐rank test, P = 0.003).ConclusionsPlasma neopterin levels significantly increased in HFpEF and correlated with the severity of HF. Furthermore, high neopterin were significantly correlated with future cardiovascular events, indicating that measurement of plasma neopterin might provide clinical benefits for risk stratification of HFpEF patients. © 2015 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of the European Society of Cardiology.