Role of oxidative stress in cardiovascular diseases

Effect of Prenatal Waterpipe Tobacco Smoke Exposure on Cardiac Biomarkers in Adult Offspring Rats

Introduction:

The prevalence of waterpipe tobacco smoke (WTS) consumption is increased among pregnant woman. Prenatal cigarette smoke exposure increased the risk of developing cardiovascular diseases in offspring. The current study examined the effect of prenatal WTS exposure on inflammatory profile, oxidative stress, and cardiac biomarkers in adult offspring rats.

Methods:

Female rats received WTS (2 hours per day) or fresh air 1 day prior to mating and throughout the pregnancy period. The body and heart masses were measured in male offspring rats. The level of oxidative stress biomarkers, nitrate, inflammatory mediators (interleukin 6 [IL-6], tumor necrosis factor alpha [TNF-α]), and gene expression of protein kinase C epsilon, angiotensin 2 receptor one, and transforming growth factor beta1 were measured in cardiac tissue homogenates of 13-week-old male offspring rats.

Results:

Prenatal WTS exposure reduced body weight and increased heart to body weight ratio ( P < .05). Prenatal WTS exposure did not affect oxidative stress biomarkers (superoxide dismutase, glutathione peroxidase, and thiobarbituric acid reactive substances) but significantly increased catalase activity and nitrate level ( P < .05) in cardiac tissue of adult male offspring rats. In addition, prenatal exposure to WTS did not affect cardiac level of TNF-α and IL-6 as well as the gene expression of different cardiac modulators in adult male offspring rats ( P > .05).

Conclusion:

Prenatal WTS exposure has detrimental consequences on adult offspring rats by increasing the ratio of heart to body mass, increasing the catalase activity and nitrate level in cardiac tissue of adult male offspring rats.

Terminalia arjuna extract and arjunic acid mitigate cobalt chloride-induced hypoxia stress-mediated apoptosis in H9c2 cells

Arjunic acid (AA) is one of the major active component of Terminalia arjuna known for its health benefits. In the present study, we evaluated cardioprotective potential of Terminalia arjuna extract (TAE) and AA against cobalt chloride (CoCl₂)-induced hypoxia damage and apoptosis in rat cardiomyocytes. TAE (50 μg/ml) and AA (8 μg/ml) significantly (p < 0.001) protected H9c2 cells as evidenced by cell viability assays against CoCl₂ (1.2 mM)-induced cytotoxicity. TAE and AA pretreatments protected the cells from oxidative damage by decreasing the generation of free radicals (ROS, hydroperoxide, and nitrite levels). TAE and AA pretreatments retained mitochondrial membrane potential by alleviating the rate of lipid peroxidation induced by CoCl₂ treatment. TAE and AA pretreatments elevated antioxidant status including phase II antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase) and total glutathione levels against CoCl₂-induced oxidative stress. Further immunoblotting studies confirmed anti-apoptotic effects of TAE and AA by alleviating the phosphorylation of JNK and c-jun and also by regulating protein expression levels of Bcl2, Bax, caspase 3, heat shock protein-70, and inducible nitric oxide synthase. Overall, our results suggest that both the extract and the active component exhibit antioxidant and anti-apoptotic defense against CoCl₂-induced hypoxic injury.

Carbonyl reductase sniffer from the model organism daphnia: Cloning, substrate determination and inhibitory sensitivity

Carbonyl reductases (CRs) represent a fundamental enzymatic defense mechanism against oxidative stress. While commonly two carbonyl reductases (CBR1 and CBR3) are found in mammalian genomes, invertebrate model organisms like Drosophila melanogaster express no CR but a functional homolog to human CBR1, termed sniffer. The importance of sniffer could be demonstrated in D. melanogaster where it protected against age-dependent neurodegeneration. Interestingly, the microcrustacean Daphnia harbors four copies of the CR gene (CR1, CR2, CR3, CR4) in addition to one sniffer gene. Due to this unique equipment Daphnia is an ideal model organism to investigate the function of sniffer. Recombinant sniffer from D. magna und D. pules were produced in E. coli, purified by Ni-affinity chromatography and tested with a variety of aliphatic and aromatic diketones, reactive aldehydes and precursors of advanced glycation end products (AGE). The highest catalytic activities were determined for sniffer from D. pulex with the aromatic dicarbonyls 9,10-phenanthrenequinone (k_cat/K_m = 2.6 s^-1 x μM^-1) and isatin (k_cat/K_m = 1.5 s^-1 x μM^-1). While sniffer from D. magna displayed preference for the same two substances, the respective catalytic activities were noticeably lower. Kinetic constants with aliphatic diketones were generally lower than those with aromatic dicarbonyls for both sniffer enzymes. The best aliphatic diketone as substrate for sniffer from D. magna and D. pulex was hexane-3,4-dione with k_cat/K_m = 0.23 s^-1 μM^-1 and k_cat/K_m = 0.35 s^-1 μM^-1, respectively. Poor or no detectable activity of the two sniffer enzymes was seen with the aliphatic diketones 2,5-hexanedione and 3,5-heptanedione, the aldehydes butanal, hexanal, decanal, crotonaldehyde, acrolein, trans-2-hexenal, and the AGE precursors glyoxal, methylglyoxal, furfural and glyceraldehyde, indicating no physiological function in the metabolism of short-chain aldehydes. Substrate inhibition for both sniffer enzymes was observed with the quinone substrates 1,4-naphthoquinone and 2-methyl-1,4-benzoquinone. From a variety of pesticides endosulfan turned out as an effective inhibitor of the sniffer enzymes (Ki = 9.2 μM for sniffer from D. magna, Ki = 12.0 μM for sniffer from D. pulex). In conclusion, the present results on sniffer from the protein superfamily of the short-chain dehydrogenases/reductases (SDR) in Daphnia ssp. complement earlier studies on carbonyl reductases in the same species and indicate that Daphnia is an interesting model to study the overall response to carbonyl stress.

Monitoring the antioxidant activities by extracting the polyphenolic contents of algae collected from the Bosphorus

The identification and quantification of ascorbic acid, phenolic acids and flavonoids were carried out simultaneously with a rapid method of reverse-phase high-performance liquid chromatography (RP-HPLC). Total flavonoid contents were being determined by UV-Vis spectrophotometry, and total phenolic contents were determined by UV-Vis spectrophotometry using the Folin-Ciocalteu Reagent (FCR) method. In all of the individual contents and total phenolic content analysis, the best results were obtained with the methanol-water solvent system. The methanol-hexane solvent system was selected as the best for the extraction of total flavonoid contents. The reason for this difference is the flavonoids in the analyzed samples which were the lipophilic character. Examining the algae species, the highest contents were achieved from Ulva lactuca and Ceramium rubrum species. Depending on industrial activity and the population density, regional characteristics have been shown to be effective in the changes of these contents which show antioxidant properties.

Approaches and Methods to Measure Oxidative Stress in Clinical Samples: Research Applications in the Cancer Field

Reactive oxygen species (ROS) are common by-products of normal aerobic cellular metabolism and play important physiological roles in intracellular cell signaling and homeostasis. The human body is equipped with antioxidant systems to regulate the levels of these free radicals and maintain proper physiological function. However, a condition known as oxidative stress (OS) occurs, when ROS overwhelm the body's ability to readily detoxify them. Excessive amounts of free radicals generated under OS conditions cause oxidative damage to proteins, lipids, and nucleic acids, severely compromising cell health and contributing to disease development, including cancer. Biomarkers of OS can therefore be exploited as important tools in the assessment of disease status in humans. In the present review, we discuss different approaches used for the evaluation of OS in clinical samples. The described methods are limited in their ability to reflect on OS only partially, revealing the need of more integrative approaches examining both pro- and antioxidant reactions with higher sensitivity to physiological/pathological alternations. We also provide an overview of recent findings of OS in patients with different types of cancer. Identification of OS biomarkers in clinical samples of cancer patients and defining their roles in carcinogenesis hold great promise in promoting the development of targeted therapeutic approaches and diagnostic strategies assessing disease status. However, considerable data variability across laboratories makes it difficult to draw general conclusions on the significance of these OS biomarkers. To our knowledge, no adequate comparison has yet been performed between different biomarkers and the methodologies used to measure them, making it difficult to conduct a meta-analysis of findings from different groups. A critical evaluation and adaptation of proposed methodologies available in the literature should therefore be undertaken, to enable the investigators to choose the most suitable procedure for each chosen biomarker.

Novel function of VEGF-B as an antioxidant and therapeutic implications

Oxidative stress, due to insufficiency of antioxidants or over-production of oxidants, can lead to severe cell and tissue damage. Oxidative stress occurs constantly and has been shown to be involved in innumerable diseases, such as degenerative, cardiovascular, neurological, and metabolic disorders, cancer, and aging, thus highlighting the vital need of antioxidant defense mechanisms. Vascular endothelial growth factor B (VEGF-B) was discovered a long time ago, and is abundantly expressed in most types of cells and tissues. VEGF-B remained functionally mysterious for many years and later on has been shown to be minimally angiogenic. Recently, VEGF-B is reported to be a potent antioxidant by boosting the expression of key antioxidant enzymes. Thus, one major role of VEGF-B lies in safeguarding tissues and cells from oxidative stress-induced damage. VEGF-B may therefore have promising therapeutic utilities in treating oxidative stress-related diseases. In this review, we discuss the current knowledge on the newly discovered antioxidant function of VEGF-B and the related molecular mechanisms, particularly, in relationship to some oxidative stress-related diseases, such as retinitis pigmentosa, age-related macular degeneration, diabetic retinopathy, glaucoma, amyotrophic lateral sclerosis, Alzheimer's disease, and Parkinson's disease.

The harmful effects of acute PM2.5 exposure to the heart and a novel preventive and therapeutic function of CEOs

Epidemiological researches have demonstrated the relationship between PM2.5 exposure and increased morbidity and mortality of cardiovascular injury. However, no effective therapeutic method was established. The purpose of this study is to investigate the effect of acute PM2.5 exposure on the mice heart tissue and explore the therapeutic effects of compound essential oils (CEOs) in this model. In this study, after mice were exposed to PM2.5 intratracheally, some obvious histopathological changes as well as some great alterations of proinflammatory cytokines were observed in the heart tissue. The imbalance of oxidative stress, the altered Ca2+ channel related proteins and the increased intracellular free Ca2+ were all involved in the heart impairment and would also be investigated in this model. The CEOs alleviated the heart impairment via its antioxidant effect rather than its anti-inflammatory function because our results revealed that oxidative stress related indicators were restored after CEOs administration. At the same time, increased concentration of intracellular free Ca2+ and ROS induced by PM2.5 were reduced after NAC (N-Acetyl-L-cysteine) administration. These data suggested that the acute PM2.5 exposure would damage heart tissue by inducing the inflammatory response, oxidative stress and intracellular free Ca2+ overload. PM2.5-induced oxidative stress probably increase intracellular free Ca2+ via RYR2 and SERCA2a. CEOs have the potential to be a novel effective and convenient therapeutic method to prevent and treat the acute heart impairment induced by PM2.5 via its antioxidant function.

The prognostic value of nitrotyrosine levels in coronary heart disease: long-term evaluation in the Acute Coronary Syndrome Registry Strategy (ERICO study)

INTRODUCTION

We aimed to analyze the association of nitrotyrosine (N-TYR) levels and long-term survival in an ongoing coronary heart disease (CHD) prospective cohort, the Acute Coronary Syndrome Registry Strategy (ERICO study).

METHODS

N-TYR levels collected during acute and subacute phase from onset of acute coronary syndrome (ACS) symptoms (myocardial infarction and unstable angina) were evaluated in 342 patients. We calculated case-fatality rates (180-days, 1 year, 2 years and 4 years) and survival analyses up to 4 years using Kaplan-Meier curves and Cox regression with respective cumulative hazard ratios (95% confidence interval; 95%CI), according to N-TYR tertiles up to 4 years of follow-up. Models are presented as crude, age and sex-adjusted and further adjusted for lipids and other confounders.

RESULTS

Overall, median level of N-TYR was 208.33 nmol/l (range: 3.09 to 1500 nmol/l), regardless ACS subtype. During follow-up of 4 years, we observed 44 (12.9%) deaths. Overall survival rate was 298 (87.1%) (Survival days: 1353, 95%CI: 1320-1387 days). N-TYR levels did not associate with mortality / survival rates up to 4 years.

CONCLUSIONS

No relationship was found between N-TYR levels and mortality rates after ACS during 4-year follow-up in the ERICO study.

Sources of Vascular Nitric Oxide and Reactive Oxygen Species and Their Regulation

Nitric oxide (NO) is a small free radical with critical signaling roles in physiology and pathophysiology. The generation of sufficient NO levels to regulate the resistance of the blood vessels and hence the maintenance of adequate blood flow is critical to the healthy performance of the vasculature. A novel paradigm indicates that classical NO synthesis by dedicated NO synthases is supplemented by nitrite reduction pathways under hypoxia. At the same time, reactive oxygen species (ROS), which include superoxide and hydrogen peroxide, are produced in the vascular system for signaling purposes, as effectors of the immune response, or as byproducts of cellular metabolism. NO and ROS can be generated by distinct enzymes or by the same enzyme through alternate reduction and oxidation processes. The latter oxidoreductase systems include NO synthases, molybdopterin enzymes, and hemoglobins, which can form superoxide by reduction of molecular oxygen or NO by reduction of inorganic nitrite. Enzymatic uncoupling, changes in oxygen tension, and the concentration of coenzymes and reductants can modulate the NO/ROS production from these oxidoreductases and determine the redox balance in health and disease. The dysregulation of the mechanisms involved in the generation of NO and ROS is an important cause of cardiovascular disease and target for therapy. In this review we will present the biology of NO and ROS in the cardiovascular system, with special emphasis on their routes of formation and regulation, as well as the therapeutic challenges and opportunities for the management of NO and ROS in cardiovascular disease.

Plasma glutathione suggests oxidative stress is equally present in early- and late-onset bipolar disorder

OBJECTIVES

We previously demonstrated oxidative stress in bipolar patients and a relationship between the age of illness onset and total glutathione, a principal antioxidant. In this study, we sought to replicate these findings in a new cohort of patients.

METHODS

We recruited bipolar patients from Warneford Hospital, Oxford, UK, of similar age and grouped them according to age of onset of illness. The early-onset group comprised patients with onset at <23 years, and the late group comprised patients with onset at >30 years. A third group, comprising age-matched healthy volunteers, was also included. Reduced and oxidized glutathione, cysteine, and cystine were determined in plasma, using high-performance liquid chromatography. Mitochondrial DNA copy number, measured in whole blood, was also compared between patients and healthy controls.

RESULTS

Significant increases in oxidative stress were observed in the patient groups, compared with the control group; however, no differences in glutathione-related oxidative stress measures were detected between the early- and late-onset bipolar patient groups. No differences were observed in the amount of mitochondrial DNA, and there was no correlation with mood state.

CONCLUSION

Using a more accurate method to quantify oxidative stress than in our previous study, we show that oxidative stress is a consistent feature of bipolar disorder. Although we did not reproduce our finding correlating age of onset of illness to oxidative stress, we have shown, once again, that oxidative stress is a consistent feature of bipolar disorder.

HSPB7 gene polymorphism associated with anthropometric parameters of obesity and fat intake in a Central European population

OBJECTIVE

Heat shock proteins act as chaperones at the molecular level and therefore they have been investigated in numerous diseases associated with oxidative stress, including obesity. The aim of this study was to investigate the possible associations of genetic variability in the 3´-untranslated region of the HSPB7 gene (rs1048261) with anthropometric and dietary parameters in a cohort of lean and obese Central European subjects.

METHODS

A total of 708 Central European Caucasian individuals were enrolled in this study, 415 obese subjects and 293 non-obese subjects. The rs1048261 genotypes were established using a conventional PCR-based methodology.

RESULTS

Significant differences were observed in the total daily fat intake between subjects with AT and TT genotypes (82.6 ± 29.2 g vs. 74.1 ± 31.3 g, p = 0.023) and also borderline significance in daily proportion of fat in the diet between AA and TT genotypes (36.0 ± 4.4% vs. 33.3 ± 5.9%, p = 0.061). Based on the linear regression model we found association between rs1048261 genotype and body fat percentage.

CONCLUSIONS

To the best of our knowledge, this is the first study which reports an association of defined genetic variability in the HSPB7 gene, rs1048261, with obesity and its associated anthropometric characteristics and dietary composition.

Identification of six cardiovascular risk biomarkers in the young population: A promising tool for early prevention

BACKGROUND AND AIMS

The predictive value of traditional CV risk calculators is limited. Novel indicators of CVD progression are needed particularly in the young population. The main aim of this study was the identification of a molecular profile with added value to classical CV risk estimation.

METHODS

Eighty-one subjects (30-50 years) were classified in 3 groups according to their CV risk: healthy subjects; individuals with CV risk factors; and those who had suffered a previous CV event. The urine proteome was quantitatively analyzed and significantly altered proteins were identified between patients' groups, either related to CV risk or established organ damage. Target-MS and ELISA were used for confirmation in independent patients' cohorts. Systems Biology Analysis (SBA) was carried out to identify functional categories behind CVD.

RESULTS

4309 proteins were identified, 75 of them differentially expressed. ADX, ECP, FETUB, GDF15, GUAD and NOTCH1 compose a fingerprint positively correlating with lifetime risk estimate (LTR QRISK). Best performance ROC curve was obtained when ECP, GDF15 and GUAD were combined (AUC = 0.96). SBA revealed oxidative stress response, dilated cardiomyopathy, signaling by Wnt and proteasome, as main functional processes related to CV risk.

CONCLUSIONS

A novel urinary protein signature is shown, which correlates with CV risk estimation in young individuals. Pending further confirmation, this six-protein-panel could help in CV risk assessment.

Cardioprotective Effect of Ethanolic Leaf Extract of Melissa Officinalis L Against Regional Ischemia-Induced Arrhythmia and Heart Injury after Five Days of Reperfusion in Rats

Melissa officinalis has antioxidant and anti-inflammatory activities and is used in various diseases. Aim of the study: We investigated the role of M. officinalis extract (MOE) against ischemia-induced arrhythmia and heart injury after five days of reperfusion in an in-vivo rat model of regional heart ischemia. The leaf extract of M. officinalis was standardized through HPLC analysis. Adult male Sprague-Dawley rats (n = 32) were subjected to 30 min of ischemia by occlusion of the left anterior descending coronary artery followed by 5 days of reperfusion. The rats (n = 8 in each group) were randomized to receive vehicle or M. officinalis as follows: group I served as saline control with ischemia, groups II, III and IV received different doses of MOE- (25, 50 and 100 mg/kg, respectively), by oral gavage daily for 14 days prior to ischemia. Administration of M. officinalis significantly improved ischemia/reperfusion (I/R)-induced myocardial dysfunction by reduction of infarct size, also, during the ischemic period, ventricular tachycardia, and ventricular ectopic beats episodes decreased as compared with that of the control group. Stabilized ST segment changes and QTc shortening increased the R and T wave amplitudes and the heart rate during ischemia. The extract also caused significant elevations in serum superoxide dismutase (SOD) activity as well as a significant decrease in serum cardiac troponin I (CTnI), lactate dehydrogenase (LDH), and malondialdehyde (MDA) levels, 5 days after reperfusion. MOE-100mg/kg was the effective dose. Cinamic acid (21.81 ± 1.26 mg/gr) was the main phenolic compound of plant sample. The ethanol extract of M. officinalis was observed to exhibit cardioprotective effects against I/R injury, probably due to antioxidant properties. The results indicate that MOE has antioxidant and cardio-protective effects against ischemia-induced arrhythmias and ischemia-reperfusion induced injury as was reflected by reduction of infarct size and cardiac injury biomarkers. These data support the potential uses of M. officinalis in the treatment of heart ischemia- reperfusion disorders and even developing new anti- arrhythmias drugs after further investigations.

Dietary total antioxidant capacity (TAC) among candidates for coronary artery bypass grafting (CABG) surgery: Emphasis to possible beneficial role of TAC on serum vitamin D

Aims

Recently, the clinical importance of total antioxidant capacity (TAC) and its protective role against several chronic diseases like cardiovascular disease, osteoporosis and several types of cancers has been reported. However, its association with cardio-metabolic risk factors among patients candidate for coronary artery bypass graft surgery (CABG) has not been evaluated yet. CABG is associated with increased oxidative stress and free radicals; so, the current study was aimed to evaluate the potential association of TAC with cardiovascular risk factors among patients candidate for CABG.

Methods and materials

In the current cross-sectional study, 454 patients aged 35–80 years as candidates of CABG and hospitalized in Tehran Heart Center were enrolled. Anthropometric and demographic characteristics were obtained from all participants. Total dietary antioxidant capacity (TAC) was calculated according to the findings of semi-quantitative food-frequency questionnaire (FFQ). Biochemical parameters including serum lipids, albumin, creatinine, HbA1C, C-reactive protein (CRP), lipoprotein (a), creatinine, blood urea nitrogen (BUN) and serum vitamin D concentrations were also assessed by commercial laboratory methods.

Results

Male patients in the top quintiles of TAC had significantly lower prevalence of hypertension (35.1% vs 45.9%). Moreover, male patients at fifth quintile of TAC were 2% more serum vitamin D concentrations, 3% lower serum cholesterol concentrations compared with lowest quintile. Top quintiles of TAC make patients more likely to have low hematocrit and high serum albumin concentrations compared with lowest quintiles (P < 0.05). However, in female participants, only serum creatinine concentration was in negative association with TAC. In comparison of clinical parameters, females in the fifth quintile of TAC had 9% higher EF compared with patients in the first quintile (P = 0.021).

Conclusion

To our findings, higher dietary antioxidant capacity was associated with lower prevalence of hypertension, lower hematocrit, total cholesterol and higher albumin and vitamin D concentrations. Therefore, high dietary TAC could be considered as a potent protective tool against cardio-metabolic risk factors in patients CABG candidate for especially in male patients.

Hydrogen peroxide constricts rat arteries by activating Na+-permeable and Ca2+-permeable cation channels

Oxidative stress is associated with many cardiovascular diseases, such as hypertension and arteriosclerosis. Oxidative stress reportedly activates the L-type voltage-gated calcium channel (VDCC_L) and elevates [Ca²⁺]_i in many cells. However, how oxidative stress activates VDCC_L under clinical setting and the consequence for arteries are unclear. Here, we examined the hypothesis that hydrogen peroxide (H₂O₂) regulates membrane potential (Em) by altering Na⁺ influx through cation channels, which consequently activates VDCC_L to induce vasoconstriction in rat mesenteric arteries. To measure the tone of the endothelium-denuded arteries, a conventional isometric organ chamber was used. Membrane currents and Em were recorded by the patch-clamp technique. [Ca²⁺]_i and [Na⁺]_i were measured with microfluorometry using Fura2-AM and SBFI-AM, respectively. We found that H₂O₂ (10 and 100 µM) increased arterial contraction, and nifedipine blocked the effects of H₂O₂ on isometric contraction. H₂O₂ increased [Ca²⁺]_i as well as [Na⁺]_i, and depolarised Em. Gd³⁺ (1 µM) blocked all these H₂O₂-induced effects including Em depolarisation and increases in [Ca²⁺]_i and [Na⁺]_i. Although both nifedipine (30 nM) and low Na⁺ bath solution completely prevented the H₂O₂-induced increase in [Na⁺], they only partly inhibited the H₂O₂-induced effects on [Ca²⁺]_i and Em. Taken together, the results suggested that H₂O₂ constricts rat arteries by causing Em depolarisation and VDCC_L activation through activating Gd³⁺-and nifedipine-sensitive, Na⁺-permeable channels as well as Gd³⁺-sensitive Ca²⁺-permeable cation channels. We suggest that unidentified Na⁺-permeable cation channels as well as Ca²⁺-permeable cation channels may function as important mediators for oxidative stress-induced vascular dysfunction.

Anti-Inflammatory, Antioxidant, and Hypolipidemic Effects of Mixed Nuts in Atherogenic Diet-Fed Rats

Nut consumption is associated with reduced risk of cardiovascular disease (CVD). Because most studies have administered single nut varieties, it is unknown whether mixed nuts will also reduce CVD risk. The objective of this study was to compare the effects of mixed nut and pistachio consumption on lipid profiles, glucose, inflammation, oxidative stress, and antioxidant capacity in rats fed an atherogenic diet. Thirty male Sprague-Dawley rats (21 days old) were assigned into three groups (n = 10) based on initial body weight and fed either an isocaloric control diet (no nuts), 8.1% pistachio diet (single nut), or 7.5% mixed nut diet (almonds, brazil nuts, cashews, macadamia nuts, peanuts, pecans, pistachios, and walnuts) for 8 weeks. Both pistachios and mixed nuts significantly decreased triglycerides, total cholesterol, and LDL-cholesterol (p < 0.05) compared with controls. Both nut groups exhibited reductions in C-reactive protein (p = 0.045) and oxidative stress (p = 0.004). The mixed nut group had greater superoxide dismutase (p = 0.004) and catalase (p = 0.044) and lower aspartate aminotransferase (p = 0.048) activities. Gene expression for Fas, Hmgcr, and Cox2 was downregulated for both nut groups compared to controls (p < 0.05). In conclusion, mixed nuts and individual nut varieties have comparable effects on CVD risk factors in rats.

Resveratrol: from enhanced biosynthesis and bioavailability to multitargeting chronic diseases

Resveratrol, a phytoalexin with a wide range of pharmacological properties is synthesised by plants in response to stress, injury, infection or UV radiations. As it is a secondary metabolite with many health promoting properties, various methods employing microorganisms and genetic manipulation of different synthetic enzymes, have been comprehensively studied to increase its production. Its rapid metabolism and low bioavailability have been addressed by the use of bio enhancers and nano-formulations. This flavonoid is extensively researched due to its pharmacological properties such as anti-oxidative, anti-inflammatory and immuno-modulating effects. Knowledge of these properties of resveratrol has led to elaborate studies on its effect on diabetes, neurodegenerative diseases, cancer, ageing, obesity and cardiovascular diseases. At molecular level it targets sirtuin, adenosine monophosphate kinase, nuclear Factor-κB, inflammatory cytokines, anti-oxidant enzymes along with cellular processes such as angiogenesis, apoptosis, mitochondrial biogenesis, gluconeogenesis and lipid metabolism. This review discusses the properties of resveratrol and the different approaches of addressing the unfavourable synthesis and pharmacokinetics of this stilbene. Pre-clinical evaluations of resveratrol on diabetes mellitus, cardiovascular and neurological diseases are elaborately discussed and the underlying pathways involved in its therapeutic activity have been given paramount importance. Following the pre-clinical studies, clinical trials on the same reveal the efficacy of resveratrol in the effective management of these diseases. This review provides an intricate insight on resveratrol's significance from a dietary component to a therapeutic agent.

Polyphenols in the prevention and treatment of periodontal disease: A systematic review of in vivo, ex vivo and in vitro studies

Plant-derived polyphenols with antimicrobial and immunomodulatory characteristics appear to provide a variety of oral health benefits. Thus, the aim of the present study was to review the scientific literature to identify these effects of polyphenols on periodontal pathogens and inflammation. A MEDLINE search from 1st January 2013 to 18th January 2018 was performed to identify studies reporting polyphenol-containing plant extracts. Reports regarding pure compounds and essential oils, as well as effects on bacteria that are not defined as periodontal pathogens, were excluded. Thirty-eight studies matched the selection criteria. Studies on immunomodulatory effects included in vitro, ex vivo, and in vivo studies (n = 23), whereas studies reporting antibacterial effects against periodontal pathogens included only in vitro studies (n = 18). Three studies were included in both groups. The antibacterial effects were characterised by inhibition of bacterial growth, adhesion to oral cells, and enzymatic activity. Decreased secretion of pro-inflammatory and increased secretion of anti-inflammatory cytokines were demonstrated. Higher attachment levels, lower inflammation, and bone loss were reported by in vivo studies. Due to the high heterogeneity, it is difficult to draw clear conclusions for applicability; nevertheless, polyphenols have great potential as antimicrobial and immunomodulatory substances in the treatment and prevention of periodontal disease.

Reactive Oxygen Species: the Dual Role in Physiological and Pathological Conditions of the Human Body

Reactive oxygen species (ROS) are well-known for playing a dual role as destructive and constructive species. Indeed, ROS are engaged in many redox-governing activities of the cells for the preservation of cellular homeostasis. However, its overproduction has been reported to result in oxidative stress, which is considered as a deleterious process, and is involved in the damage of cell structures that causes various diseased states. This review provides a concise view on some of the current research published in this topic for an improved understanding of the key roles of ROS in diverse conditions of health and disease. Previous research demonstrated that ROS perform as potential signaling molecules to control several normal physiological functions at the cellular level. Additionally, there is a growing body of evidence supporting the role of ROS in various pathological states. The binary nature of ROS with their profitable and injurious characteristics indicates the complexities of their specific roles at a biological compartment and the difficulties in establishing convenient intervention procedures to treat ROS-related diseases.

Pentacyclic triterpenes: New tools to fight metabolic syndrome

BACKGROUND

Metabolic syndrome is a combination of dysregulated cardiometabolic risk factors characterized by dyslipidemia, impaired glucose tolerance, insulin resistance, inflammation, obesity as well as hypertension. These factors are tied to the increased risk for type-II diabetes and cardiovascular diseases including myocardial infarction in patients with metabolic syndrome.

PURPOSE

To review the proposed molecular mechanisms of pentacyclic triterpenes for their potential use in the metabolic syndrome.

METHODS

PubMed, Science Direct, and Google Scholar database were searched from commencement to April 2018. Following keywords were searched in the databases with varying combinations: "metabolic syndrome", "pentacyclic triterpenes", "transcription factors", "protein kinase", "lipogenesis", "adipogenesis", "lipolysis", "fatty acids", "gluconeogenesis", "cardiovascular", "mitochondria", "oxidative stress", "pancreas", "hepatic cells", "skeletal muscle", "3T3-L1", "C2C12", "obesity", "inflammation", "insulin resistance", "glucose uptake", "clinical studies" and "bioavailability".

RESULTS

Pentacyclic triterpenes, such as asiatic acid, ursolic acid, oleanolic acid, 18β-glycyrrhetinic acid, α,β-amyrin, celastrol, carbenoxolone, corosolic acid, maslinic acid, bardoxolone methyl and lupeol downregulate several metabolic syndrome components by regulating transcription factors, protein kinases and enzyme involved in the adipogenesis, lipolysis, fatty acid oxidation, insulin resistance, mitochondria biogenesis, gluconeogenesis, oxidative stress and inflammation.

CONCLUSION

In vitro and in vivo studies suggests that pentacyclic triterpenes effectively downregulate various factors related to metabolic syndrome. These phytochemicals may serve as promising candidates for clinical trials for the management of metabolic syndrome.

Studies on the effects of microencapsulated human mesenchymal stem cells in RGD-modified alginate on cardiomyocytes under oxidative stress conditions using in vitro biomimetic co-culture system

Stem cell therapy has been recognized as a promising approach for myocardium regeneration post myocardial infarction (MI); however, it unfortunately often remains a challenge because of poor survival of transplanted cells and a lack of clear understanding of their interactions with host cells. High oxidative stress at heart tissues post MI is considered one of the important factors damaging transplanted cells and native cells/tissues. Here, we employed an in vitro co-culture system, capable of mimicking cases of stem cell transplantation into the myocardium presenting high oxidative stress, using human mesenchymal stem cells (hMSCs) encapsulated in alginate or cell interactive Arg-Gly-Asp (RGD) peptide-modified alginate micro-hydrogels. Under H₂O₂-induced oxidative stress conditions, viabilities of hMSCs and CMs were significantly higher in their co-culture than in their individual monolayer cultures. Expression of cardiac muscle markers remained high even with H₂O₂ treatment when cardiomyocytes (CMs) were co-cultured with hMSCs in RGD-alginate. Higher levels of various growth factors (associated with angiogenesis, cardiac regeneration, and contractility) were found in co-culture (noticeably with RGD-alginate) compared to monolayer cultures of CMs or hMSCs. These results can benefit the study of in vivo MI progression with transplanted stem cells and the development of effective stem cell-based therapeutic strategies for various oxidative stress-related diseases.

Short-Term Cardiovascular Response to Short-Radius Centrifugation With and Without Ergometer Exercise

Artificial gravity (AG) has often been proposed as an integrated multi-system countermeasure to physiological deconditioning associated with extended exposure to reduced gravity levels, particularly if combined with exercise. Twelve subjects underwent short-radius centrifugation along with bicycle ergometry to quantify the short-term cardiovascular response to AG and exercise across three AG levels (0 G or no rotation, 1 G, and 1.4 G; referenced to the subject's feet and measured in the centripetal direction) and three exercise intensities (25, 50, and 100 W). Continuous cardiovascular measurements were collected during the centrifugation sessions using a non-invasive monitoring system. The cardiovascular responses were more prominent at higher levels of AG and exercise intensity. In particular, cardiac output, stroke volume, pulse pressure, and heart rate significantly increased with both AG level (in most of exercise group combinations, showing averaged increments across exercise conditions of 1.4 L/min/g, 7.6 mL/g, 5.22 mmHg/g, and 2.0 bpm/g, respectively), and workload intensity (averaged increments across AG conditions of 0.09 L/min/W, 0.17 mL/W, 0.22 mmHg/W, and 0.74 bpm/W respectively). These results suggest that the addition of AG to exercise can provide a greater cardiovascular benefit than exercise alone. Hierarchical regression models were fitted to the experimental data to determine dose-response curves of all cardiovascular variables as a function of AG-level and exercise intensity during short-radius centrifugation. These results can inform future studies, decisions, and trade-offs toward potential implementation of AG as a space countermeasure.

The therapeutic and diagnostic role of exosomes in cardiovascular diseases

Exosomes are nano-sized membranous vesicles that are secreted by cells. They have an important role in transferring proteins, mRNA, miRNA and other bioactive molecules between cells and regulate gene expression in recipient cells. Therefore, exosomes are a mechanism by which communication between cells is achieved and they are involved in a wide range of physiological processes, especially those requiring cell-cell communication. In the cardiovascular system, exosomes are associated with endothelial cells, cardiac myocytes, vascular cells, stem and progenitor cells, and play an essential role in development, injury and disease of the cardiovascular system. In recent years, accumulating evidence implicates exosomes in the development and progression of cardiovascular disease. Additionally, exosomal microRNAs are considered to be key players in cardiac regeneration and confer cardioprotective and regenerative properties on both cardiac and non-cardiac cells and, additionally, stem and progenitor cells. Notably, miRNAs may be isolated from blood and offer a potential source of novel diagnostic and prognostic biomarkers for cardiovascular disease. In this review, we summarize and assess the functional roles of exosomes in cardiovascular physiology, cell-to-cell communication and cardio-protective effects in cardiovascular disease.

The controversial role of vitamin D as an antioxidant: results from randomised controlled trials

Increased oxidative stress has been implicated as a potential causal factor in the development of several diseases. In the last decade, an extensive literature has been produced on vitamin D, not limited to its well-known function like a steroid hormone on skeletal tissue, but for its potential pleiotropic role in human health. Several researchers have suggested relationships between vitamin D intake and health outcomes such as cancer prevention and increased immunity, or possible role in preventing diabetes, and in inflammation. Little is known about its antioxidant effect. The aim of the present review was to explore major evidence regarding the potential scavenger capacity of vitamin D in high-evidence human studies. Studies considered by the present review suggest that the potential role of vitamin D as an antioxidant could not be confirmed. Current literature showed controversial effects about the ability of cholecalciferol to prevent or ameliorate oxidative stress biomarkers, and there is need of further and high-quality studies testing the antioxidant effect of vitamin D supplementation.

Impact of swimming exercise on inflammation in medullary areas of sympathetic outflow control in spontaneously hypertensive rats

Exercise reduces sympathetic activity (SA), arterial pressure and heart rate in spontaneously hypertensive rats (SHR). Exercise increases oxidative stress (OS) and inflammation is implicated in the generation of reactive oxygen species (ROS) and progression of hypertension. To unravel these effects of exercise and considering that SA is driven by medullary areas, we hypothesized that swimming exercise (SW) affects the gene expression (g.e.) of proteins involved in inflammation and OS in the commissural Nucleus of the Solitary Tract (cNTS) and Rostral ventrolateral medulla (RVLM), which control the sympathetic outflow in SHR. We used male SHR and Wistar rats (14-16wks-old) which were maintained sedentary (SED) or submitted to SW (1 h/day, 5 days/wk./6wks). The g.e. of cycloxygenase-2 (COX-2), interleukin 6 (IL-6), interleukin 10 (IL-10), AT-1 receptor (AT-1r), neuroglobin (Ngb) and cytoglobin (Ctb) in cNTS and RVLM was carried out by qPCR. We observed that COX-2 g.e. increased in SW-SHR in cNTS and RVLM compared to SED-SHR. The IL-6 g.e. reduced in RVLM in SW-SHR, whereas IL-10 g.e. increased in SW-SHR in comparison to SED-SHR. The AT-1r g.e. decreased in SW-SHR in cNTS and RVLM compared to SED-SHR. The Ngb and Ctb g.e. in cNTS neurons increased in SHR and Wistar rats submitted to SW compared to SED, but only Ctb g.e. increased in RVLM in SW-SHR and Wistar in comparison to SED. Therefore, the SW altered the g.e. in cNTS and RVLM for reducing the inflammation and ROS formation, which is increased particularly in SHR, consequently decreasing the OS.

Effects of oral antidiabetic drugs on left ventricular mass in patients with type 2 diabetes mellitus: a network meta-analysis

Background

We used a network meta-analysis of randomized controlled trials (RCTs) to comparatively examine the effects of oral antidiabetic drugs (OADs) on left ventricular mass (LVM) in patients with type 2 diabetes.

Methods

Document searches were implemented using Medline, Cochrane Controlled Trials Registry, and ClinicalTrials.gov. We decided to include RCTs that evaluated the impact of LVM using the administration of OADs to patients with type 2 diabetes. The outcome evaluations used standardized mean difference (SMD) and 95% confidence intervals (CIs). We then performed a comparative examination of LVM related to the administration of OADs using random effects network meta-analysis.

Results

The document search found 11 RCTs (1410 people) that satisfied the eligibility criteria for this study, and these RCTs were incorporated into the network meta-analysis. The only medication that significantly reduced LVM compared to a placebo was gliclazide (SMD, −1.09; 95% CI, −1.62 to  − 0.57). Further, when comparing the impact on LVM between OADs, only gliclazide significantly reduced LVM compared to other OADs (glyburide, voglibose, metformin, pioglitazone, rosiglitazone, and sitagliptin).

Conclusions

In the present study, gliclazide was the only medication that significantly reduced LVM in patients with type 2 diabetes. When considered from the perspective of causing heart failure and preventing recurrence, it is possible that the use of gliclazide in patients with type 2 diabetes will provide multiple benefits.

The Falconoid Luteolin Mitigates the Myocardial Inflammatory Response Induced by High-Carbohydrate/High-Fat Diet in Wistar Rats

Luteolin is a major component of many medicinal plants and traditional medicines. The current study aims at testing its protective effect against high-carbohydrate/high-fat (HCHF) diet-induced cardiac dysfunction in rats. Male Wistar rats were divided into six groups as follows: control group that received standard rat chow, group received HCHF diet (~ 30% carbohydrate and 42% fat) daily for 16 weeks, and four groups received HCHF diet concurrently with luteolin (10, 25, 50 or 100 mg/kg; 10% w/v suspension in 0.9% NaCl) daily from the first week by oral gavage. Body weight was measured weekly. At the end of the study, histopathological examinations of stained heart sections were carried out. Lipid profile, oxidative stress, and cardiac function biomarkers were measured. Furthermore, neurohumoral mediators and inflammatory cytokines (TNF-α, IL-18) were assigned. Results showed a significant improvement in cardiac function, tissue integrity, and a decrease in the compensatory neurohumoral mediators by luteolin 50 and 100 mg/kg. In addition, a significant (P < 0.05) decrease in collagen deposition, fibrosis percentage, lipid peroxidation, and inflammatory cells (macrophages and lymphocytes) infiltration was observed. Tested doses of luteolin decreased lipid peroxidation and elevated the endogenous antioxidant biomarkers (reduced glutathione and superoxide dismutase) significantly (P < 0.05). Finally, luteolin decreased TNF-α and IL-18 (P < 0.001) in a dose-dependent manner. It can be concluded that luteolin has a cardioprotective effect against HCHF diet-induced myocardial inflammation through antioxidant anti-inflammatory mechanisms.

Cardioprotective Effects of Nanoemulsions Loaded with Anti-Inflammatory Nutraceuticals against Doxorubicin-Induced Cardiotoxicity

Doxorubicin is a highly active antineoplastic agent, but its clinical use is limited because of its cardiotoxicity. Although nutraceuticals endowed with anti-inflammatory properties exert cardioprotective activity, their bioavailability and stability are inconsistent. In an attempt to address this issue, we evaluated whether bioavailable nanoemulsions loaded with nutraceuticals (curcumin and fresh and dry tomato extracts rich in lycopene) protect cardiomyoblasts (H9C2 cells) from doxorubicin-induced toxicity. Nanoemulsions were produced with a high-pressure homogenizer. H9C2 cells were incubated with nanoemulsions loaded with different nutraceuticals alone or in combination with doxorubicin. Cell viability was evaluated with a modified MTT method. The levels of the lipid peroxidation products malondialdehyde (MDA) and 4-hydroxy-2-butanone (4-HNA), and of the cardiotoxic-related interleukins IL-6, IL-8, IL-1β and IL-10, tumor necrosis factor-alpha (TNF-α), and nitric oxide were analyzed in cardiomyoblasts. The hydrodynamic size of nanoemulsions was around 100 nm. Cell viability enhancement was 35–40% higher in cardiomyoblasts treated with nanoemulsion + doxorubicin than in cardiomyoblasts treated with doxorubicin alone. Nanoemulsions also protected against oxidative stress as witnessed by a reduction of MDA and 4-HNA. Notably, nanoemulsions inhibited the release of IL-6, IL-8, IL-1β, TNF-α and nitric oxide by around 35–40% and increased IL-10 production by 25–27% versus cells not treated with emulsions. Of the nutraceuticals evaluated, lycopene-rich nanoemulsions had the best cardioprotective profile. In conclusion, nanoemulsions loaded with the nutraceuticals described herein protect against cardiotoxicity, by reducing inflammation and lipid oxidative stress. These results set the stage for studies in preclinical models.

Associations and interactions between variants in selenoprotein genes, selenoprotein levels and the development of abdominal aortic aneurysm, peripheral arterial disease, and heart failure

Background

Little is known on the role of selenoprotein genes in cardiovascular disease. This study examines the associations of the SEPP1, SELENOS, TXNRD1, TXNRD2, GPX4, and SOD2 polymorphisms and selenoprotein P (SeP) and thioredoxin concentrations with the development of abdominal aortic aneurysm (AAA) and aortoiliac occlusive disease (AOID), as well as their influence on cardiac phenotype.

Methods

564 patients with AAA, 400 patients with AIOD, and 543 controls were enrolled and characterized for coronary artery disease, myocardial infarction, and systolic heart failure (HF) occurrence. In AAA, the coexistence of peripheral arterial disease (PAD) was examined. Genotypes were determined using TaqMan-based assays. Selenoprotein concentration was assessed using the ELISA method.

Results

The SELENOS rs34713741T, SEPP1 rs3877899A, and GPX4 rs713041T alleles were related to a 30–60% increase in the AIOD/PAD risk in the recessive or dominant model (all associations at P < .05). The SEPP1 rs3877899A allele was a protective factor for the development of AAA without concomitant PAD (OR = 0.68 for the dominant model, P = .014), but not AAA with concomitant PAD. The cumulative two-locus effects of selenoprotein genes on the AAA/AIOD risk were observed, including the multiplicative interaction between the SELENOS rs34713741T and GPX4 rs713041T alleles (both in the recessive model) affecting the AIOD risk (OR = 5.27, P = .001) and its clinical phenotype. Coexistence of HF in aortic diseases was related to both the SEPP1 rs7579A allele (OR = 1.83 for carriers, P = .013) and increased SeP concentrations; SeP level ≥8.5 mg/mL caused a 3.5-fold increase in the risk of HF. In AAA, SeP levels were correlated with BMI (r = -0.575, P < .0001).

Conclusions

Our results provide evidence that selenoprotein polymorphisms constitute a risk factor for HF and peripheral atherosclerosis, but prevent the development of AAA. Excessive weight might result in reduced antioxidant reserve efficiency in AAA. Validation studies are required to establish whether SeP concentration may be a marker for HF.

Sonic hedgehog signaling regulates hypoxia/reoxygenation-induced H9C2 myocardial cell apoptosis

The sonic hedgehog (Shh) signaling pathway has been reported to protect cells against hypoxia/reoxygenation (H/R) injury; however, the role of Shh and relevant molecular mechanisms remain unclear. In the present study, the rat cardiomyoblast cell line H9C2 was subjected to hypoxia and serum-starvation for 4 h. Cells were subsequently reoxygenated using 95% O₂ and 5% CO₂. Reverse transcription-quantitative polymerase chain reaction was performed to quantify the expression of Shh mRNA, while cell apoptosis was assessed using flow cytometry. Caspase-3 activity and p53 expression were measured by western blotting and an MTT assay was subsequently used to assess cell viability. In addition, reactive oxygen species levels were measured using dichlorofluorescein and H/R-induced changes in the activation of superoxide dismutase, catalase, phosphorylated-endothelial nitric oxide synthase, phosphorylated-protein kinase B (Akt) and mammalian target of rapamycin activation were assessed using western blotting. H/R treatment decreased the cell viability of H9C2 cells, but activated endogenous Shh signaling. The activation of Shh signaling protected H9C2 myocardial cells from H/R-induced apoptosis and restored cell viability. In the present study, Shh signaling was demonstrated to serve a protective role against H/R by activating the phosphoinositol 3-kinase (PI3K)/Akt pathway and promoting the expression of anti-oxidant enzymes to ameliorate oxidative stress. In summary, Shh signaling attenuated H/R-induced apoptosis through via the PI3K/Akt pathway.

Antigenotoxic potential of plant leaf extracts of Parkinsonia aculeata L. using Allium cepa assay

The aim of the present study was to evaluate the antigenotoxic potential of P. aculeata L. leaf extract/fractions against maleic hydrazide (MH) using Allium cepa root chromosomal aberration assay. The excessive reduction in root growth and mitotic index value was observed after 3 h treatment of MH as compared to negative control (water). In case of MH treatment, frequency of aberrated cells significantly (p ≤ 0.05) raised from 129 to 337 at 0.1 ppm and 2.0 ppm concentrations respectively. From root growth inhibition test with MH treatment, EC₅₀ value i.e. 0.5 ppm was selected to study the antigenotoxic effect of different extract/fractions of P. aculeata L. leaves. All the extract/fractions showed increase in mitotic index and great reduction in chromosomal aberrations with rise in concentration against the genotoxicity of MH. Among all the extract/fractions, butanol and ethyl acetate fractions showed significant reduction in chromosomal aberrations in A. cepa cells and indicates the chemo preventive activity. Antigenotoxic property of this plant is due to the presence of various phytochemicals in leaf such as epi-orientin, Parkinsonin-A, Parkinsonin-B, orientin, iso-orientin, vitexin, iso-vitexin, C-glycosylflavone, parkintin, rotenoids, terpenoids, flavonoids, saponins, alkaloids, glycosides and anthraquinone etc. Our result showed that among all the treatments, simultaneous treatment showed best result followed by pre and post treatment. Further studies in animal model are suggested for further evaluation of the use of P. aculeata leaf extract in human welfare.

Circulating γ-Tocopherol Concentrations Are Inversely Associated with Antioxidant Exposures and Directly Associated with Systemic Oxidative Stress and Inflammation in Adults

Background

Although α- and γ-tocopherol are co-consumed antioxidants, circulating γ-tocopherol concentrations were paradoxically found to be inversely associated with total vitamin E intake and circulating α-tocopherol concentrations. There are limited data on this apparent paradox or on determinants of circulating γ-tocopherol concentrations.

Objective

To help clarify possible determinants of circulating γ-tocopherol concentrations, we investigated associations of circulating γ-tocopherol concentrations with various dietary and lifestyle factors and biomarkers of oxidative stress and inflammation.

Methods

We pooled cross-sectional data from 2 outpatient, adult, elective colonoscopy populations (pooled n = 419) on whom extensive dietary, lifestyle, and medical information was collected, and the following plasma concentrations were measured: α- and γ-tocopherol (via HPLC), F2-isoprostanes (FiPs; via gas chromatography-mass spectrometry), and high-sensitivity C-reactive protein (hsCRP; via latex-enhanced immunonephelometry). Multivariable general linear models were used to assess mean γ-tocopherol differences across quantiles of plasma antioxidant micronutrients, FiPs, and hsCRP; an oxidative balance score [OBS; a composite of anti- and pro-oxidant dietary and lifestyle exposures (a higher score indicates higher antioxidant relative to pro-oxidant exposures)]; and multiple dietary and lifestyle factors.

Results

Adjusted for serum total cholesterol, mean γ-tocopherol concentrations among those in the highest relative to the lowest tertiles of circulating α-tocopherol and β-carotene, the OBS, and total calcium and dietary fiber intakes were 31.0% (P < 0.0001), 29.0% (P < 0.0001), 27.6% (P = 0.0001), 29.7% (P < 0.0001), and 18.6% (P = 0.008) lower, respectively. For those in the highest relative to the lowest tertiles of circulating FiPs and hsCRP, mean γ-tocopherol concentrations were 50% (P < 0.0001) and 39.0% (P < 0.0001) higher, respectively.

Conclusions

These findings support the conclusion that circulating γ-tocopherol concentrations are inversely associated with antioxidant exposures and directly associated with systemic oxidative stress and inflammation in adults. Additional research on possible mechanisms underlying these findings and on whether circulating γ-tocopherol may serve as a biomarker of oxidative stress, inflammation, or both is needed.

Protocatechuic aldehyde protects against isoproterenol-induced cardiac hypertrophy via inhibition of the JAK2/STAT3 signaling pathway

Protocatechuic aldehyde (PCA) is a natural compound found in the Chinese herb Salvia miltiorrhiza. It has been shown to possess multiple biological activities and to protect the cardiovascular system against oxidative stress, inflammation, and atherosclerosis. However, the potential effects of PCA on cardiac hypertrophy remain to be investigated. In this study, we showed that isoproterenol treatment (ISO, 10 μM for 24 h) induced significant hypertrophy in cultured neonatal rat cardiomyocytes, as manifested by enlargement of cell surface area (1.74-fold greater than that of the control, p < 0.05) and upregulation of hypertrophic gene markers (2.44- to 2.75-fold increase in ANF and β-MHC protein expression, p < 0.05). These ISO-induced hypertrophic responses were attenuated by PCA (50-200 μM, p < 0.05). Furthermore, intragastric administration of PCA (10-100 mg/kg/day) ameliorated cardiac hypertrophy in ISO-treated rats (1.5 mg/kg/day, s.c., for 7 days). PCA inhibited the abnormal changes in echocardiographic parameters and suppressed ISO-induced increase in cardiomyocyte cross-sectional area and collagen content (p < 0.05). It also ameliorated ISO-mediated elevation of HW/BW, LVW/BW, and HW/TL ratios (p < 0.05). Mechanistically, ISO facilitated JAK2 and STAT3 phosphorylation, increased STAT3 nuclear translocation, and enhanced STAT3 transcriptional activity. All these changes were attenuated by PCA. Taken together, these findings showed that PCA could protect against cardiac hypertrophy induced by ISO possibly via inhibition of the JAK2/STAT3 signaling pathway, suggesting the potential of PCA as a therapeutic candidate for hypertrophy-associated heart diseases.

Glutathione S-transferase P1 gene polymorphisms and susceptibility to coronary artery disease in a subgroup of north Indian population

The present study aimed to investigate the association of g.313A>G and g.341C>T polymorphisms of GSTP1 with coronary artery disease (CAD) in a subgroup of north Indian population. In the present case-control study, CAD patients (n = 200) and age-matched, sex-matched and ethnicity-matched healthy controls (n = 200) were genotyped for polymorphisms in GSTP1 using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Genotype distribution of g.313A>Gand g.341C>T polymorphisms of GSTP1 gene was significantly different between cases and controls (P = 0.005 and 0.024, respectively). Binary logistic regression analysis showed significant association of A/G (odds ratio (OR): 1.6, 95% CI: 1.08-2.49, P = 0.020) and G/G (OR: 3.1, 95% CI: 1.41-6.71, P = 0.005) genotypes of GSTP1 g.313A>G, and C/T (OR: 5.8, 95% CI: 1.26-26.34, P = 0.024) genotype of GSTP1 g.341C>T with CAD. The A/G and G/G genotypes of g.313A>G and C/T genotype of g.341C>T conferred 6.5-fold increased risk for CAD (OR: 6.5, 95% CI: 1.37-31.27, P = 0.018).Moreover, the recessive model of GSTP1 g.313A>G is the best fit inheritance model to predict the susceptible gene effect (OR: 2.3, 95% CI: 1.11-4.92, P = 0.020). In conclusion, statistically significant associations of GSTP1 g.313A>G (A/G, G/G) and g.341C>T (C/T) genotypes with CAD were observed.

Antioxidants from Plants Protect against Skin Photoaging

Exposure to UV light triggers the rapid generation and accumulation of reactive oxygen species (ROS) in skin cells, with consequent increase in oxidative stress and thus in photoaging. Exogenous supplementation with dietary antioxidants and/or skin pretreatment with antioxidant-based lotions before sun exposure might be a winning strategy against age-related skin pathologies. In this context, plants produce many secondary metabolites to protect themselves from UV radiations and these compounds can also protect the skin from photoaging. Phenolic compounds, ascorbic acid and carotenoids, derived from different plant species, are able to protect the skin by preventing UV penetration, reducing inflammation and oxidative stress, and influencing several survival signalling pathways. In this review, we focus our attention on the double role of oxidants in cell metabolism and on environmental and xenobiotic agents involved in skin photoaging. Moreover, we discuss the protective role of dietary antioxidants from fruits and vegetables and report their antiaging properties related to the reduction of oxidative stress pathways.

Genetic susceptibility of glutathione S-transferase genes (GSTM1/T1 and P1) to coronary artery disease in Asian Indians

Genetic polymorphisms in glutathione S-transferase (GST) genes may modulate the risk of cardiovascular diseases. The objective of present study was to investigate the potential association between the polymorphisms of GSTM1/T1 and P1 genes and their influence on diverse clinical parameters and oxidative stress biomarkers in coronary artery disease (CAD) patients in Asian Indians. The present study includes 562 angiographically confirmed CAD patients and 564 healthy control subjects from the north Indian population. Anthropometric and clinical measurements were performed for all the participants. The oxidative stress biomarkers including malondialdehyde and total antioxidant capacity were also measured. The genotyping of the GSTM1/T1 and P1 genes was performed using the multiplex-PCR and PCR-RFLP methods. The CAD patients exhibit significantly high values of waist circumference, waist-to-hip ratio, body fat (%), glucose, triglycerides, and very low-density lipoprotein, and reduced high-density lipoprotein levels compared to control subjects (P < 0.001). Malondialdehyde levels were significantly enhanced, and the total antioxidant capacity was reduced in CAD patients compared to controls (P < 0.001). However, no significant difference in body mass index and total cholesterol levels were observed in CAD patients and control subjects. The frequencies of the GSTM1 and GSTM1/T1 null genotypes in the CAD patients were significantly higher than the control subjects. In contrast, the GSTT1(-) genotype frequencies were significantly lower in CAD patients than the controls. Logistic regression analysis of the data revealed the null genotype of GSTM1 and the GG genotype of the GSTP1 (313A/G) gene were associated with an approximately twofold enhanced risk of developing CAD, whereas GSTT1(-) plays a defensive role against CAD development in north Indians. Upon stratification of data according to the genotypes of the GSTM1/T1 and P1 genes, we did not find significant a difference among the various metabolic traits in CAD patients and controls. Our results suggest that oxidative damage induced by lipid peroxidation with reduced antioxidant capacity and genetic variants in GST genes (GSTM1/T1 and P1) may modify the risk of CAD development in Asian Indian population.

Estrogen Modulates the Sensitivity of Lung Vagal C Fibers in Female Rats Exposed to Intermittent Hypoxia

Obstructive sleep apnea is mainly characterized by intermittent hypoxia (IH), which is associated with hyperreactive airway diseases and lung inflammation. Sensitization of lung vagal C fibers (LVCFs) induced by inflammatory mediators may play a central role in the pathogenesis of airway hypersensitivity. In females, estrogen interferes with inflammatory signaling pathways that may modulate airway hyperreactivity. In this study, we investigated the effects of IH on the reflex and afferent responses of LVCFs to chemical stimulants and lung inflammation in adult female rats, as well as the role of estrogen in these responses. Intact and ovariectomized (OVX) female rats were exposed to room air (RA) or IH for 14 consecutive days. On day 15, IH enhanced apneic responses to right atrial injection of chemical stimulants of LVCFs (e.g., capsaicin, phenylbiguanide, and α,β-methylene-ATP) in intact anesthetized females. Rats subjected to OVX prior to IH exposure exhibited an augmented apneic response to the same dose of stimulants compared with rats subjected to other treatments. Apneic responses to the stimulants were completely abrogated by bilateral vagotomy or perivagal capsaicin treatment, which blocked the neural conduction of LVCFs. Electrophysiological experiments revealed that in IH-exposed rats, OVX potentiated the excitability of LVCFs to stimulants. Moreover, LVCF hypersensitivity in rats subjected to OVX prior to IH exposure was accompanied by enhanced lung inflammation, which was reflected by elevated inflammatory cell infiltration in bronchoalveolar lavage fluid, lung lipid peroxidation, and protein expression of inflammatory cytokines. Supplementation with 17β-estradiol (E2) at a low concentration (30 μg/ml) but not at high concentrations (50 and 150 μg/ml) prevented the augmenting effects of OVX on LVCF sensitivity and lung inflammation caused by IH. These results suggest that ovarian hormones prevent the enhancement of LVCF sensitivity and lung inflammation by IH in female rats, which are related to the effect of low-dose estrogen.

Stilbenes from Veratrum maackii Regel Protect against Ethanol-Induced DNA Damage in Mouse Cerebellum and Cerebral Cortex

Ethanol is a principle ingredient of alcoholic beverages with potential neurotoxicity and genotoxicity, and the ethanol-associated oxidative DNA damage in the central nervous system is well documented. Natural source compounds may offer new options to protect the brain against ethanol-induced genotoxicity. Veratrum maackii Regel is a toxic rangeland plant linked to teratogenicity which is also used in traditional Chinese medicine as "Lilu" and is reported to contain a family of compounds called stilbenes that can have positive biological activity. In this study, nine stilbenes were isolated from the aerial parts of V. maackii Regel, and their structures were identified as cis-mulberroside A (1), resveratrol-4,3'- O-β-d-diglucopyranoside (2), mulberroside A (3), gentifolin K (4), resveratrol-3,5- O-β-d-diglucopyranoside (5), oxyresveratrol- 4'- O-β-d-glucopyranoside (6), oxyresveratrol-3- O-β-d-glucopyranoside (7), oxyresveratrol (8), and resveratrol (9) using ESI-MS and NMR techniques. The total concentration of extracted compounds 2-9 was 2.04 mg/g, suggesting that V. maackii Regel is a novel viable source of these compounds. In an in vivo comet assay, compounds 1-9 were observed to decrease DNA damage in mouse cerebellum and cerebral cortex caused by acute ethanol administration. Histological observation also revealed decreased brain injury in mice administered with compounds 1-9 after acute ethanol administration. The protective effects of compound 6 were associated with increasing T-SOD and GSH-PX activities and a decrease in NO and MDA concentrations. These findings suggest that these compounds are potent inhibitors of ethanol-induced brain injury possibly via the inhibition of oxidative stress and may be valuable leads for future therapeutic development.

Whole blood mercury and the risk of cardiovascular disease among the Greenlandic population

BACKGROUND

Studies have found mercury to be associated with cardiovascular disease (CVD), however, primarily in populations with low exposure. The highest levels, and variations in the levels, of whole blood mercury (WBM) worldwide have been found in Greenland. We prospectively assessed the association between WBM and the risk of developing CVD in the Greenlandic population.

METHODS

We assessed the effects of WBM levels on incident CVD among 3083 Greenlandic Inuit, participating in a population-based cohort study conducted from 2005 to 2010. WBM was measured at baseline. Participants were followed in the National Patient Registries for Denmark and Greenland and in the causes of death register for CVD events from inclusion in the study until CVD event, emigration, death or end of follow-up (30/9-2013). Using Cox regression analyses, we calculated the incidence rates and the hazard ratio of CVD events according to WBM levels. Potential interactions with sex were also investigated.

RESULTS

The highest levels of WBM were found in men, who had a significantly higher median level (19 μg/L (IQR:1-44)), compared with women (15 μg/L (IQR: 1-32), (p < 0.001)). The crude hazard ratio (HR) for incident CVD was 1.00 (95% CI 1.00-1.00) for 5 µg/l increase in WBM. After adjusting for several potential confounders, there was still no association between WBM and incident CVD (HR 0.99; 95%CI:0.99-1.00). We found no interactions with sex.

CONCLUSIONS

In a population with high levels of WBM, we found no association between WBM and the risk of developing CVD in Greenland.

Evaluation of prooxidant-antioxidant balance in in vitro fertilization-conceived mice

Objective

Concerns about the safety of assisted reproductive technology (ART) have been raised, as some studies have shown elevated incidence rates of childhood cancer, asthma, allergies, and other diseases in ART-conceived babies. Findings regarding the health of ART-conceived babies are controversial. The present study was conducted to evaluate the prooxidant-antioxidant balance (PAB) in in vitro fertilization (IVF)-conceived mice in comparison to naturally conceived offspring.

Methods

Mice (6-8 weeks) were divided into two groups (IVF-conceived and naturally conceived) matched by sex, age, weight, and litter size. A 1-mL blood sample was taken and the sera were separated. The oxidant-antioxidant balance was evaluated using a fast and reliable PAB assay. The results were expressed as mean±standard deviation.

Results

The mean PAB values (HK units) in the IVF-conceived and naturally conceived groups were 59.70±22.30 and 54.70±18.22, respectively (p=0.82).

Conclusion

Since free radicals contribute to several pathological conditions and antioxidants play an important protective role against oxidative stress, evaluating the oxidant-antioxidant balance is very important. Although the results of this study showed that the quality of the defense mechanism against free radicals was not significantly different between the IVF-conceived and naturally conceived mice, other parameters of metabolic dysfunction need to be measured.

Reliability of arterial stiffness indices at rest and following a single bout of moderate-intensity exercise in older adults

Short-term changes in arterial stiffness with exercise are proposed to better reflect vascular impairments than resting measures alone and are suggested as a prognostic indicator of cardiovascular risk in older adults. Arterial stiffness indices are reliable at rest, but the time-course and reliability of postexercise changes in arterial stiffness in older adults are unknown. The precision of postexercise changes in arterial stiffness should be determined prior to their use in large prospective trials. This study assessed the between-day reliability of the changes in pulse wave velocity (PWV), augmentation index (AIx75) and reflection magnitude (RM) following an exercise bout in older adults. Ten older adults (71 ± 5 years) were tested on three separate days, 7 days apart. PWV, AIx75 and RM were assessed at rest, immediately post and at 20, 40 and 60 min during recovery after moderate-intensity cycling. Intraclass correlation coefficient (ICC) and reliability coefficient (RC) were used to assess the relative and absolute reliability of arterial stiffness responses. PWV increased, and RM decreased immediately after exercise (P<0·05), and returned to baseline during recovery. AIx decreased during recovery (P<0·001). Resting ICC values were 0·91 (PWV), 0·72 (AIx75) and 0·40 (RM). Reliability of the immediate changes following exercise was high for PWV (ICC:0·87, RC:1·9 m s^-1 ) and moderate for AIx75 (ICC:0·64, RC:7%) and RM (ICC:0·59, RC:9%). Reliability of the postexercise responses was similar to that at rest for all measures of arterial stiffness. These findings indicate that postexercise changes in arterial stiffness indices are reliable in healthy older adults and supports further investigation of the prognostic value of these responses.

Metabolomic Approach to Redox and Nitrosative Reactions in Cardiovascular Diseases

Metabolomics, also referred to as metabonomics, is one of the most recent innovative technologies in medicine. It offers a direct functional read-out of phenotypes by the detection, identification, and quantification of a large number of metabolites within a biological sample such as urine and blood. Metabolites (<1500 Da) represent the output of cellular metabolism, accounting for expression and activity of genes, transcripts, and proteins, and offering unique insights into small molecule regulation, which may uncover new biochemical patterns. Metabolomics research has considerable potential for translating the metabolic fingerprint into personalized therapeutic strategies. Within the field of interest, cardiovascular disease (CVD) is one of the most developed areas. However, CVD remains the leading cause of death worldwide with a marked increase in mortality rates over the past six decades. In this scenario, recent findings indicate the important role of redox and nitrosative (RN) reactions in CVD development and progression. RN reactions are generally involved in the homeostatic modulation of a wide number of cellular and organ functions. Conversely, the imbalance of these reactions may lead to a condition of allostasis that in turn can cause CVD. The aim of this review is to highlight how the use of metabolomics may be useful for the study of RN reactions related to CVD, providing a tool to understand the mechanisms underlying reactions that could lead to impaired ROS or RNS formation.

Associations between hypertension and the peroxisome proliferator-activated receptor-δ (PPARD) gene rs7770619 C>T polymorphism in a Korean population

Background

Oxidative stress is associated with the increased risk of hypertension (HTN). This cross-sectional study is aimed to identify the association between the peroxisome proliferator-activated receptor-δ (PPARD) polymorphism and plasma malondialdehyde (MDA), an oxidative stress marker which is related to HTN development, and to determine whether PPARD gene is a candidate gene for HTN.

Results

One thousand seven hundred ninety-three individuals with normal blood pressure (BP) and HTN were included in this cross-sectional study. The Korean Chip was used to obtain genotype data. Through the analysis, the ten most strongly associated single-nucleotide polymorphisms (SNPs) were nominated for an MDA-related SNP. Among them, the rs7770619 polymorphism was identified in the PPARD gene. The CT genotype of the PPARD rs7770619 C>T polymorphism was associated with a lower risk of HTN before and after adjustments for age, sex, body mass index, smoking, and drinking. Significant associations were observed between plasma MDA and the PPARD rs7770619 C>T polymorphism and between systolic BP and the PPARD rs7770619 SNP in the controls. The CT controls showed significantly lower systolic BP and plasma MDA than the CC controls. Additionally, in both controls and HTN patients, the CT subjects showed significantly lower serum glucose and higher adiponectin levels than the CC subjects. Furthermore, the CT subjects showed significantly higher serum free fatty acid levels than the CC subjects among the HTN patients.

Conclusion

This is a new finding that the PPARD rs7770619 C>T SNP is a novel candidate variant for HTN based on the association between PPARD and plasma MDA in a Korean population.

Electronic supplementary material

The online version of this article (10.1186/s40246-018-0162-6) contains supplementary material, which is available to authorized users.