The free oxygen radicals test (FORT) to assess circulating oxidative stress in patients with acute myocardial infarction

Unlocking the link between haptoglobin polymorphism and noninfectious human diseases: insights and implications

Haptoglobin (Hp) is a polymorphic protein that was initially described as a hemoglobin (Hb)-binding protein. The major functions of Hp are to scavenge Hb, prevent iron loss, and prevent heme-based oxidation. Hp regulates angiogenesis, nitric oxide homeostasis, immune responses, and prostaglandin synthesis. Genetic polymorphisms in the Hp gene give rise to different phenotypes, including Hp 1-1, Hp 2-1, and Hp 2-2. Extensive research has been conducted to investigate the association between Hp polymorphisms and several medical conditions including cardiovascular disease, inflammatory bowel disease, cancer, transplantation, and hemoglobinopathies. Generally, the Hp 2-2 phenotype is associated with increased disease risk and poor outcomes. Over the years, the Hp 2 allele has spread under genetic pressures. Individuals with the Hp 2-2 phenotype generally exhibit lower levels of CD163 expression in macrophages. The decreased expression of CD163 may be associated with the poor antioxidant capacity in the serum of subjects carrying the Hp 2-2 phenotype. However, the Hp 1-1 phenotype may confer protection in some cases. The Hp1 allele has strong antioxidant, anti-inflammatory, and immunomodulatory properties. It is important to note that the benefits of the Hp1 allele may vary depending on genetic and environmental factors as well as the specific disease or condition under consideration. Therefore, the Hp1 allele may not necessarily confer advantages in all situations, and its effects may be context-dependent. This review highlights the current understanding of the role of Hp polymorphisms in cardiovascular disease, inflammatory bowel disease, cancer, transplantation, hemoglobinopathies, and polyuria.

Systemic Oxidative Stress in Women with Ovarian and Pelvic Endometriosis: Role of Hormonal Therapy

This study was performed to evaluate the systemic oxidative stress balance in women with either ovarian or deep infiltrating endometriosis (DIE) and any alterations of the same during hormone therapy. Free oxygen radicals (FORT) and free oxidant radical defense (FORD) were measured in the capillary blood of 24 women without endometriosis, 26 women with endometrioma, and 26 women with DIE with or without endometrioma. Endometriosis was diagnosed by clinical and ultrasound assessment. Dietary factors, lifestyle habits, and intake of any substances interfering with the oxidative status were recorded. Women were prescribed contraceptive hormones, and the baseline assessments were repeated at the 3rd month of use, revealing a higher oxidative stress balance (FORT/FORD) in women with endometriosis than in controls (4.75 ± 4.4 vs. 2.79 ± 2.2; p = 0.05). The highest values were found in women with DIE (5.34 ± 4.6; p = 0.028 vs. controls). Regression analysis revealed an independent link between FORT/FORD and endometrioma (b 2.874, 95% CI 0.345, 5.403; p = 0.027) and DIE (b 4.419, 95% CI 1.775, 7.064; p = 0.001) but a negative correlation with HDL-cholesterol (b -0.063, 95% CI -0.125, -0.002; p = 0.043). In controls, the hormone therapy increased FORT (p = 0.003), but also FORD (p = 0.012), with the FORT/FORD balance remaining stable (2.72 ± 2.2 vs. 2.73 ± 1.8; p = 0.810). In women with endometriosis, FORT remained unchanged, but FORD increased (p = 0.004), and the FORT/FORD ratio significantly decreased (4.75 ± 4.4 vs. 2.57 ± 1.76; p = 0.002) to values similar to the control levels. These data indicate that systemic oxidative stress balance increased in women with endometriosis, particularly in those with DIE. The hormonal therapy did not change the oxidative stress balance in control women but significantly improved it in women with endometriosis, particularly those suffering from DIE.

Retinitis Pigmentosa (RP): The Role of Oxidative Stress in the Degenerative Process Progression

Purpose: Retinitis Pigmentosa is a term that includes a group of inherited bilateral and progressive retinal degenerations, with the involvement of rod photoreceptors, which frequently leads to blindness; oxidative stress may be involved in the degeneration progression as proposed by several recent studies. The goal of this study is to evaluate whether circulating free radicals taken from capillary blood are related to one of the most important features of Retinitis pigmentosa that can affect frequently patients: cystoid macular oedema (CME). Materials: A total of 186 patients with Retinitis Pigmentosa (range: 25−69 years) were enrolled; all patients completed an ophthalmologic examination and SD-OCT at baseline and were divided into three subgroups according to the SD-OCT features. ROS blood levels were determined using FORT with monitoring of free oxygen radicals. Results: Test levels of free oxygen radicals were significantly increased, almost twice, in RP patients showing cystoid macular oedema and significantly increased compared to the control group. (p < 0.001). Discussion: Our findings suggest that oxidative stress may speed cone photoreceptors’ morphological damage (CMT); because long lasting oxidative stress in the RP may cause oxidative damage, with animal models of RP suggesting this is a micromolecular mechanism of photoreceptors’ (cone) death, it can be similar to cone damage in human RP eyes. The limitations of this paper are the relatively small sample, the horizontal design of the study, and the lack of data about the levels of ROS in the vitreous body.

Cardioprotective effects of resveratrol following myocardial ischemia and reperfusion

Resveratrol (RSV), a plant origin polyphenol, has shown beneficial cardiovascular effects. In this study, isolated hearts from male Wistar rats were studied using the Langendorff technique. Following 30 min stabilization, the hearts underwent 30 min global ischemia and 120 min reperfusion. The perfusion solution in the test group contained RSV (10 μM). Hemodynamics of the hearts, the markers of myocardial damage including creatine kinase-MB (CK-MB), lactate dehydrogenase (LDH), and troponin I were studied during the study. Furthermore, the infarct size and the markers of oxidative stress including catalase (CAT), superoxide dismutase (SOD), malondialdehyde (MDA), and glutathione peroxidase (GPX) were assayed in the homogenates of the hearts. The release of nitrite from the hearts and the occurrence of ventricular arrhythmias were also monitored throughout the experiment. Resveratrol caused a significant improvement in the restoration of the mechanical performance of the hearts following myocardial ischemia and reperfusion (MIR). Besides, the infarct size, CK-MB, LDH, and troponin I declined in the test group. Besides, the cardiac release of nitrite increased, and the redox status of the heart was improved as indicated by the levels of CAT, SOD, GPX, and MDA. Finally, the treatment caused significant decreases in the occurrences of single and salvo arrhythmias, ventricular tachycardia, and ventricular fibrillation. The current study suggests strong cardioprotective and antiarrhythmic effects for RSV following MIR.

Melatonin elicits protective effects on OGD/R‑insulted H9c2 cells by activating PGC‑1α/Nrf2 signaling

Melatonin (Mel) elicits beneficial effects on myocardial ischemia/reperfusion injury. However, the underlying mechanism of Mel against oxygen-glucose deprivation/ reperfusion (OGD/R)-induced H9c2 cardiomyocyte damage remains largely unknown. The aim of the present study was to investigate the biological roles and the potential mechanisms of Mel in OGD/R-exposed H9c2 cardiomyocytes. The results of the present study demonstrated that Mel significantly elevated the viability and reduced the activity of lactate dehydrogenase and creatine kinase myocardial band in a doseand time-dependent manner in OGD/R-insulted H9c2 cells. In addition, Mel suppressed OGD/R-induced oxidative stress in H9c2 cells, as demonstrated by the decreased reactive oxygen species and malondialdehyde levels, as well as the increased activities of superoxide dismutase, catalase and glutathione peroxidase. Mel exerted an antioxidant effect by activating the peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α)/nuclear factor erythroid 2-related factor 2 (Nrf2) signaling. Mel reduced the expression of OGD/R-enhanced pro-inflammatory tumor necrosis factor-α (TNF-α), interleukin (IL)-6, IL-1β, IL-8 and monocyte chemotactic protein-1. Mel also abolished the OGD/R-induced increase in H9c2 apoptosis, as evidenced by mitochondrial membrane potential restoration and caspase-3 and caspase-9 inactivation, as well as the upregulation of Bcl-2 and down-regulation of cleaved caspase-3 and Bax. The Mel-induced antiapoptotic effects were dependent on PGC-1α/TNF-α signaling. Overall, the results of the present study demonstrated that Mel alleviated OGD/R-induced H9c2 cell injury via the inhibition of oxidative stress and inflammation by regulating the PGC-1α/Nrf2 and PGC-1α/TNF-α signaling pathways, suggesting a promising role for Mel in the treatment of ischemic heart disease.

Plasma concentrations of molecular lipid species predict long-term clinical outcome in coronary artery disease patients

We investigated the associations of ten previously identified high risk molecular lipid species and three ceramide ratios with the occurrence of major adverse cardiac events (MACEs) during a median follow-up of 4.7 years in patients with coronary artery disease (CAD). Between 2008 and 2011, 581 patients underwent diagnostic coronary angiography or percutaneous coronary intervention for stable angina pectoris (SAP) or acute coronary syndrome (ACS). Blood was drawn prior to the index procedure and lipid species were determined. The primary endpoint was the occurrence of a MACE, comprising all-cause mortality, nonfatal ACS, or unplanned coronary revascularization. The secondary endpoint comprised all-cause mortality or nonfatal ACS. During a median follow-up of 4.7 [IQR: 4.2-5.6] years, 155 patients (27%) had MACEs. In multivariable analyses, Cer(d18:1/16:0) concentration was associated with MACEs {hazard ratio 2.32; 95% CI [1.09-4.96] per natural logarithm (ln) (pmol/ml) P = 0.030} after adjustment for cardiac risk factors, clinical presentation, statin use at baseline, and admission nonHDL cholesterol level. Furthermore, after multivariable adjustment, concentrations of Cer(d18:1/16:0), Cer(d18:1/20:0), Cer(d18:1/24:1), and their ratios to Cer(d18:1/24:0) were associated with the composite endpoint death or nonfatal ACS. The data together show the circulating ceramide lipids we investigated here are associated with adverse cardiac outcome during long-term follow-up independent of clinical risk factors.

Arctigenin exerts protective effects against myocardial infarction via regulation of iNOS, COX‑2, ERK1/2 and HO‑1 in rats

The present study aimed to determine the protective effects of arctigenin against myocardial infarction (MI), and its effects on oxidative stress and inflammation in rats. Left anterior coronary arteries of Sprague‑Dawley rats were ligated, in order to generate an acute MI (AMI) model. Arctigenin was administered to AMI rats at 0, 50, 100 or 200 µmol/kg. Western blotting and ELISAs were performed to analyze protein expression and enzyme activity. Arctigenin was demonstrated to effectively inhibit the levels of alanine transaminase, creatine kinase‑MB and lactate dehydrogenase, and to reduce infarct size in AMI rats. In addition, the activity levels of malondialdehyde, interleukin (IL)‑1β and IL‑6 were significantly suppressed, and the levels of glutathione peroxidase, catalase and superoxide dismutase were significantly increased by arctigenin treatment. Arctigenin treatment also suppressed the protein expression levels of inducible nitric oxide synthase (iNOS), cyclooxygenase 2 (COX‑2) and heme oxygenase 1 (HO‑1), and increased the protein expression levels of phosphorylated‑extracellular signal‑regulated kinase 1/2 (p‑ERK1/2) in AMI rats. Overall, the results of the present study suggest that arctigenin may inhibit MI, and exhibits antioxidative and anti‑inflammatory effects through regulation of the iNOS, COX‑2, ERK1/2 and HO‑1 pathways in a rat model of AMI.

Relation between high levels of myeloperoxidase in the culprit artery and microvascular obstruction, infarct size and reverse remodeling in ST-elevation myocardial infarction

MAIN OBJECTIVE

To better understand the role of myeloperoxidases (MPO) in microvascular obstruction (MO) phenomenon and infarct size (IS) using cardiac magnetic resonance (CMR) data in patients with acute myocardial infarction (AMI).

METHOD

40 consecutive patients classified according to the median level of MPO in the culprit artery. A CMR study was performed during the week following AMI and at 6 months, with late gadolinium enhancement sequences.

RESULTS

Persistent MO was observed in the same proportion (50 vs. 65%, p = 0.728) between the low vs. high MPO group levels. However, the extent of the microvascular obstruction was significantly greater in the high-MPO group (6 (0-9) vs.16.5 (0-31), p = 0.027), together with a greater infarct size, and a trend towards a lower left ventricular ejection fraction (LVEF) (p = 0.054) at one week. CMR data at 6 months showed that reverse systolic remodeling was two fold more present in the low-MPO group (p = 0.058). Interestingly, the extent of MO (8.5 (6.5-31) vs. 4.1 (3-11.55), p = 0.042) and IS remained significantly greater (24.5 (9.75-35) vs. 7.5 (2.5-18.75), p = 0.022) in the high-MPO group. Moreover, MPO in the culprit artery appeared to correlate positively with MPO in non-culprit arteries and serum, and with troponin levels and peak CK.

CONCLUSION

This patient-based study revealed in patients after AMI that high MPO levels in the culprit artery were associated with more severe microvascular obstruction and greater IS. These findings may provide new insights pathophysiology explanation for the adverse prognostic impact of MO.

Circulating levels of reactive oxygen species in patients with nonproliferative diabetic retinopathy and the influence of antioxidant supplementation: 6-month follow-up

Aims:

The aim was to evaluate circulating levels of reactive oxygen species (ROS) and changes in central macular thickness (CMT) in patients with nonproliferative diabetic retinopathy (NPDR) after antioxidant supplementation.

Materials and Methods:

A total of 68 patients (68 eyes) with NPDR were enrolled. Patients were randomly divided into two groups: Treated with antioxidant supplement (Group A) and untreated control group (Group B). Each tablet, for oral administration, containing pycnogenol 50 mg, Vitamin E 30 mg and coenzyme Q10 20 mg. CMT and free oxygen radical test (FORT) were analyzed at baseline (T0), 3 (T1) and 6 (T2) months in both groups.

Results:

In Group A, FORT levels and CMT were significantly reduced over time (P < 0.001 for both). In Group B, FORT levels were increased (P < 0.001) and CMT did not vary significantly (P = 0.81) over 3 time points.

Conclusions:

This is the first study showing the reduction of ROS levels in patients with NPDR thanks to antioxidant therapy. Moreover, our findings have suggested also an influence on retinal thickness.

Haptoglobin polymorphism in relation to coronary plaque characteristics on radiofrequency intravascular ultrasound and near-infrared spectroscopy in patients with coronary artery disease

BACKGROUND

Conflicting results exist regarding the association between a common Haptoglobin (Hp) polymorphism and risk of coronary artery disease. We investigated the association of three functionally different anti-oxidant and anti-inflammatory Hp phenotypes (Hp1-1, Hp2-1, Hp2-2) with invasively measured degree and composition of coronary atherosclerosis as determined by intravascular ultrasound (-virtual histology) (IVUS(-VH)) as well as near-infrared spectroscopy (NIRS).

METHODS

Non-culprit coronary artery segments of 581 patients with acute coronary syndrome (ACS) or stable angina pectoris were imaged with IVUS(-VH). In 203 patients, the segments were also imaged with NIRS. Pre-procedural blood samples were drawn for Hp phenotyping. Degree (segment plaque volume, segment plaque burden (PB); presence of lesions with PB≥70%) and composition (segment fractions of fibrous, fibro-fatty, dense calcium, and necrotic core tissue; presence of IVUS-VH derived thin-cap fibroatheroma lesions) of coronary atherosclerosis were measured.

RESULTS

No differences were present between the three Hp phenotypes with regard to degree and composition of coronary atherosclerosis in the full cohort. However, ACS patients with a Hp2-1 or Hp2-2 phenotype had a higher segment PB percentage (β[95% CI]: 3.88[0.31-7.44], p=0.033), increased prevalence of lesions with PB≥70% (OR[95% CI]: 3.61[1.06-12.30], p=0.040), and a tendency towards a higher segment plaque volume (β[95% CI]: 1.29[-0.04-2.62], p=0.056) in multivariable analyses.

CONCLUSIONS

Although in the full cohort no associations could be demonstrated between Hp phenotypes and plaque characteristics, a significant association was present between phenotypes resulting from a genotype containing a Hp2 allele (Hp2-1 or Hp2-2) and a higher degree of atherosclerosis in patients with ACS.

Alpha-lipoic acid: molecular mechanisms and therapeutic potential in diabetes

Diabetes is a chronic metabolic disease with a high prevalence worldwide. Diabetes and insulin resistance are associated with the development of cardiovascular and nervous diseases. The development of these disorders reflects complex pathological processes in which the oxidative stress caused by reactive oxygen species (ROS) and reactive nitrogen species (RNS) plays a pivotal role. It is widely accepted that diabetes impairs endothelial nitric oxide synthase (eNOS) activity and increases the production of ROS, thus resulting in diminished NO bioavailability and increased oxidative stress. Alpha-lipoic acid (LA) possesses beneficial effects both in the prevention and in the treatment of diabetes. LA is a potent antioxidant with insulin-mimetic and anti-inflammatory activity. LA in the diet is quickly absorbed, transported to the intracellular compartments, and reduced to dihydrolipoic acid (DHLA) under the action of enzymes. LA, which plays an essential role in mitochondrial bioenergetic reactions, has drawn considerable attention as an antioxidant for use in managing diabetic complications such as retinopathy, neuropathy and other vascular diseases.

NF-E2-related factor 2 over-expression in mesenchymal stem cells to improve cellular cardiomyoplasty

Myocardial infarction (MI) is the leading cause of death worldwide. Various therapeutic strategies have been introduced for MI treatment. In recent years, interest in utilizing mesenchymal stem cells (MSCs) for MI therapy has increased. In fact, the use of MSCs for MI treatment, known as cellular cardiomyoplasty, is in the clinical trial stage. However, despite promising results, most MSCs die after transplantation as a result of exposure to various stresses. Nuclear factor (erythroid-derived 2)-like 2 (Nrf2), a well-known cytoprotective transcription factor, protects MSCs against some stresses. Over-expression of Nrf2 in MSCs decreases their apoptosis in vitro without any adverse effects on their differentiation capacity. Therefore, we hypothesized that over-expression of Nrf2 in MSCs can improve cellular cardiomyoplasty.

Relation between oxidative stress and climacteric symptoms in early postmenopausal women

OBJECTIVES

To evaluate the relation between climacteric symptoms or other risk factors for cardiovascular disease and oxidative status of postmenopausal women.

METHODS

Cross-sectional investigation performed at the outpatient service for the menopause at the University Hospital, on 50 apparently healthy women in physiological postmenopause. The whole-blood free oxygen radical test (FORT), free oxygen radical defence (FORD), age, months since menopause, weight, body mass index, waist circumference, waist-to-hip ratio, estradiol, lipids, glucose, insulin, insulin resistance (glucose/insulin and HOMA-IR), and fibrinogen were evaluated. The Greene Climacteric Scale with its subscales was used to evaluate climacteric symptoms. The pulsatility index, an index of downstream blood flow resistance, was determined for both the internal carotid artery and the brachial artery.

RESULTS

The waist-to-hip ratio (r = 0.540; p = 0.0001), estradiol (r = 0.548; p = 0.0004) and waist circumference (r = 0.345; p = 0.02) were independently related to blood FORT. The score in the Greene vasomotor subscale was the only parameter independently related to blood FORD (r = 0.554; p = 0.0001). FORT was not related to the artery pulsatility index, while FORD was negatively related to the pulsatility index of both the internal carotid (r = 0.549; p = 0.0001) and the brachial (r = 0.484; p = 0.0001) arteries.

DISCUSSION

In postmenopausal women, abdominal adiposity and hypoestrogenism increase oxidative stress. Climacteric symptoms, particularly vasomotor symptoms, markedly reduce antioxidant defences. Lower antioxidant defences are associated with higher resistance to blood flow in the great arteries. In women early after the menopause, visceral fat, hypoestrogenism and climacteric symptoms may increase the risk for cardiovascular disease.

Growth differentiation factor-15 (GDF-15) levels are associated with cardiac and renal injury in patients undergoing coronary artery bypass grafting with cardiopulmonary bypass

OBJECTIVE

Growth differentiation factor-15 (GDF-15) has been identified as a strong marker of cardiovascular disease; however, no data are available concerning the role of GDF-15 in the occurrence of organ dysfunction during coronary artery bypass grafting (CABG) associated with cardiopulmonary bypass (CPB).

METHODS

Five arterial blood samples were taken sequentially in 34 patients from anesthesia induction (IND) until 24 h after arrival at the intensive care unit (ICU). Plasma levels of GDF-15, follistatin-like 1 (FLST1), myeloperoxidases (MPO), hydroperoxides and plasma antioxidant status (PAS) were measured at each time-point. Markers of cardiac (cardiac-troponin I, cTnI) and renal dysfunction (neutrophil gelatinase-associated lipocalin, NGAL) and other classical biological factors and clinical data were measured.

RESULTS

Plasma GDF-15 levels increased gradually during and after surgery, reaching nearly three times the IND levels in the ICU (3,075±284 ng/L vs. 1,061±90 ng/L, p<0.001). Plasma MPO levels increased dramatically during surgery, attaining their highest level after unclamping (UNCLAMP) (49±11 ng/mL vs. 1,679±153 ng/mL, p<0.001) while PAS significantly decreased between IND and UNCLAMP (p<0.05), confirming the high oxidative status induced by this surgical procedure. ICU levels of GDF-15 correlated positively with cTnI and NGAL (p = 0.006 and p = 0.036, respectively), and also with hemoglobin and estimated glomerular filtration rate (eGFR). Among all the post-operative biomarkers available, only eGFR, NGAL and GDF-15 measured at ICU arrival were significantly associated with the onset of acute kidney injury (AKI). Patients with a EuroSCORE >3 were shown to have higher GDF-15 levels.

CONCLUSIONS

During cardiac surgery associated with CPB, GDF-15 levels increased substantially and were associated with markers of cardiac injury and renal dysfunction.

Folate administration decreases oxidative status and blood pressure in postmenopausal women

PURPOSE

The purpose of this study was to evaluate whether folate exerts antioxidant effects in postmenopausal women and whether this effect is related to folate-induced modification of 24-h ambulatory blood pressure (BP).

METHODS

Double-blind placebo-controlled study performed in 30 apparently healthy postmenopausal women recruited at the outpatient service of University Hospital. Women, free from hormones or substances possibly interfering with the investigated parameters, were randomized to receive orally for 3 weeks placebo (n = 15) or 15 mg/day of 5-methyltetrahydrofolate (5-MTHF; n = 15). Whole-blood free oxygen radicals test (FORT), free oxygen radical defence (FORD), lipids, glucose, insulin, insulin resistance [homeostatic model assessment for insulin resistance (HOMA-IR)], homocysteine and 24-h ambulatory BP values were evaluated.

RESULTS

In the entire group of women, FORT was independently and inversely related to the day-night difference of diastolic (r = 0.420; p = 0.03) and mean BP (r = 0.497; p = 0.01). Placebo did not affect any biochemical or BP parameter. 5-MTHF reduced FORT (-71.5 ± 98.2; p = 0.02) and increased FORD (0.5 ± 0.9; p = 0.05), decreased insulin (p = 0.01), HOMA-IR (p = 0.0002) and homocysteine (p = 0.008). During 5-MTHF, night-time mean (p = 0.001) and diastolic BP (p = 0.002) decreased of about 5 mmHg and the day-night difference of mean (p = 0.001) and diastolic BP (p = 0.002) contemporaneously increased. FORT reduction was related to the amplification of the nocturnal decline of mean (0.697; p = 0.006) and diastolic BP (r = 0.777; p = 0.002) and to the amplification of the day-night difference of diastolic BP (r = 0.63; p = 0.015).

CONCLUSIONS

Present data show a clear reduction of oxidative stress during 5-MTHF administration and a strong correlation between this decrease and the nocturnal decline of BP. The possible link between the two is worthy to be explored.

Genotoxic and oxidative damage potentials in human lymphocytes after exposure to terpinolene in vitro

Terpinolene (TPO) is a monocyclic monoterpene found in the essential oils of various fir and pine species. Recent reports indicated that several monoterpenes could exhibit antioxidant effects in both human and animal experimental models. However, so far, the nature and/or biological roles of TPO have not been elucidated in human models yet. The aim of this study was to investigate the genetic, oxidative and cytotoxic effects of TPO in cultured human blood cells (n = 5) for the first time. Human blood cells were treated with TPO (0-200 mg/L) for 24 and 48 h, and then cytotoxicity was detected by lactate dehydrogenase (LDH) release and [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT) assay, while DNA damage was also analyzed by micronucleus assay, sister chromatid exchanges assay and 8-oxo-2-deoxyguanosine (8-OH-dG) level. In addition, biochemical parameters [total antioxidant capacity (TAC) and total oxidative stress (TOS)] were examined to determine oxidative effects. The results of LDH and MTT assays showed that TPO (at concentrations greater than 100 mg/L) decreased cell viability. In our in vitro test systems, it was observed that TPO had no genotoxicity on human lymphocytes. Again, TPO (at 10, 25, 50 and 75 mg/L) treatment caused statistically important (p < 0.05) increases of TAC levels in human lymphocytes without changing TOS levels. In conclusion, TPO can be a new resource of therapeutics as recognized in this study with its non-genotoxic and antioxidant features.

The Association between Oxidative Stress and Metabolic Syndrome in Adults

BACKGROUND

In this Study, we investigated the effects of lifestyle and metabolic syndrome on free oxygen radical levels in men and women in Korea.

METHODS

A total of 254 adults were included in this study from February 2011 to June 2012 at a health promotion center. Information of the lifestyles and presence of metabolic syndrome factors was obtained. Biochemical markers were measured and free oxygen radicals test (FORT) was performed on the blood.

RESULTS

Of the 254 subjects, 86 (33.9%) had metabolic syndrome, and 187 (73.6%) were men. Between the subjects with and without metabolic syndrome, there was a significant increase in alanine aminotransferase and serum FORT values in the subjects with metabolic syndrome. Multiple linear regression analysis showed that high-sensitivity C-reactive protein (hs-CRP) (P = 0.004), metabolic syndrome (P = 0.037), and female gender (P = 0.030) were independent predictors of serum FORT values. The subjects with high fasting blood sugar level or low high density lipoprotein cholesterol levels showed high serum FORT values.

CONCLUSION

High hs-CRP, the presence of metabolic syndrome, and female gender were associated with the high oxidative stress. High oxidative stress was associated with the presence of metabolic syndrome.

In vitro assessment of cytogenetic and oxidative effects of α-pinene

α-Pinene (α-pinene), a bicyclic monoterpene, is present in the oils of many species of coniferous trees, most notably the pine, and is known for its diverse biological properties such as antimicrobial, anti-inflammatory, antiproliferative and antioxidant. However, there are limited data on the cytogenetic and antioxidant effects of α-pinene in cultured human blood cells (n = 5) for the first time. The purpose of this study was to investigate the genetic, oxidative, and cytotoxic effects of α-pinene in cultured human blood cells (n = 5) for the first time. Human blood cells were treated with α-pinene (0 to 200 mg/L) for 24 and 48 h, and then cytotoxicity was detected by lactate dehydrogenase (LDH) release and (3-(4,5-dimethyl-thiazol-2-yl) 2,5-diphenyltetrazolium bromide) (MTT) assay, while DNA damage was also analyzed by micronucleus (MN) assay, chromosomal aberration (CA) assay and 8-oxo-2-deoxyguanosine (8-OH-dG). In addition, biochemical parameters (total antioxidant capacity (TAC) and total oxidative stress (TOS)) were examined to determine oxidative effects. The results of LDH and MTT assays showed that α-pinene (at 200 mg/L) decreased cell viability. In our in vitro test systems, it was observed that α-pinene did not cause any statistically important changes in the rates of studied genotoxicity endpoints but dose-dependent alterations were observed in TAC and TOS levels. α-Pinene treatment caused increases in TAC levels (at 25 and 50 mg/L) and decreases in TOS levels (only at 200 mg/L) on human lymphocytes. In conclusion, the findings of the present study confirm for the first time that α-pinene could be a significant source of natural antioxidant compound that may have beneficial health effects.

Direct and indirect antioxidant properties of α-lipoic acid and therapeutic potential

Diabetes has emerged as a major threat to worldwide health. The exact mechanisms underlying the disease are unknown; however, there is growing evidence that the excess generation of reactive oxygen species (ROS) associated with hyperglycemia, causes oxidative stress in a variety of tissues. In this context, various natural compounds with pleiotropic actions like α-lipoic acid (LA) are of interest, especially in metabolic diseases such as diabetes. LA, either as a dietary supplement or a therapeutic agent, modulates redox potential because of its ability to match the redox status between different subcellular compartments as well as extracellularly. Both the oxidized (disulfide) and reduced (di-thiol: dihydro-lipoic acid, DHLA) forms of LA show antioxidant properties. LA exerts antioxidant effects in biological systems through ROS quenching but also via an action on transition metal chelation. Dietary supplementation with LA has been successfully employed in a variety of in vivo models of disease associated with an imbalance of redox status: diabetes and cardiovascular diseases. The complex and intimate association between increased oxidative stress and increased inflammation in related disorders such as diabetes, makes it difficult to establish the temporal sequence of the relationship.

Postnatal overfeeding causes early shifts in gene expression in the heart and long-term alterations in cardiometabolic and oxidative parameters

Background

Postnatal overfeeding (OF) in rodents induces a permanent moderate increase in body weight in adulthood. However, the repercussions of postnatal OF on cardiac gene expression, cardiac metabolism and nitro-oxidative stress are less well known.

Methodology/Principal Findings

Immediately after birth, litters of C57BL/6 mice were either maintained at 10 (normal-fed group, NF), or reduced to 3 in order to induce OF. At weaning, mice of both groups received a standard diet. The cardiac gene expression profile was determined at weaning and cardiac metabolism and oxidative stress were assessed at 7 months. The cardiac expression of several genes, including members of the extracellular matrix and apelin pathway, was modified in juvenile OF mice. In adult mice, OF led to an increase in body weight (+30%) and to significant increases in plasma cholesterol, insulin and leptin levels. Myocardial oxidative stress, SOD and catalase activity and mRNA expression were increased in OF mice. In vivo, diastolic and systolic blood pressures were significantly higher and LV shortening and ejection fraction were decreased in OF mice. Ex vivo, after 30 min of ischemia, hearts isolated from OF mice showed lower functional recovery and larger infarct size (31% vs. 54%, p<0.05). Increases in collagen deposition and expression/activity of matrix-metalloproteinase-2 were observed in adult OF mouse hearts. Moreover, an increase in the expression of SOCS-3 and a decrease in STAT-3 phosphorylation were observed in ventricular tissues from OF mice.

Conclusions/Significance

Our study emphasizes that over-nutrition during the immediate postnatal period in mice leads to early changes in cardiac gene expression, which may permanently modify the heart’s structural organization and metabolism and could contribute to a greater susceptibility to myocardial ischemia-reperfusion injury.

Assessment of lifestyle effects on the levels of free oxygen radicals in the korean population

Background

As many studies revealed that oxidative stress due to the imbalance of reactive oxygen species (ROS) and antioxidant capacity is related with pathologic processes such as cardiovascular diseases, diabetes, as well as aging and obesity, the relationship between lifestyle and oxidative stress has recently gained much medical attention. However, little information exists on the effects of lifestyle on ROS in Korea. In this study, we investigated the effects of lifestyle on free oxygen radical levels in men and women in Korea.

Methods

A total of 138 adults participated in this study from September 2007 to June 2010 at a health promotion center and department of family medicine. Information on the lifestyle of each participant was obtained by questionnaire. Biochemical markers and a free oxygen radical test (FORT) were also measured.

Results

The average age was 47.28 ± 10.85 years and 79.7% were male. High sensitivity C-reactive protein (hs-CRP; r = 0.418, P = 0.012), triglycerides (r = -0.243, P = 0.008), hemoglobin (r = -0.445, P < 0.001), total protein (r = 0.210, P = 0.036), creatinine (r = -0.294, P = 0.001), fruit intake per day (P = 0.047), and smoking (P = 0.003) were related to the FORT levels in univariate analysis. Multiple linear regression analysis showed that hs-CRP (P = 0.039) was an independent predictor of serum FORT values. This statistical model can explain 78% of the variance in FORT values.

Conclusion

This result suggests that hs-CRP showed a statistically significant positive association with FORT values. Further studies on the relationship between lifestyle and antioxidant capacity as well as ROS seem to be warranted to evaluate the overall effect of oxidative stress.

Effect of tacrolimus on myocardial infarction is associated with inflammation, ROS, MAP kinase and Akt pathways in mini-pigs

AIM

This study tested the hypothesis that tacrolimus therapy limited left ventricular (LV) infarct and remodeling by suppressing the inflammatory response, oxidative stress and regulating the mitogen-activated protein kinase (MAPK) and Akt signaling pathways in an acute myocardial infarction (AMI) mini-pig model by ligating the left anterior descending coronary artery (LAD).

METHODS

Twelve male mini-pigs were equally randomized into AMI treated by saline (3.0 mL) (AMI(S)), and AMI treated by tacrolimus (0.5 mg) (AMI(T)). Thirty minutes after the procedure, intra-LAD injections were performed just beyond the ligation.

RESULTS

Inflammatory biomarkers at transcription or protein levels [matrix metalloproteinase (MMP9), plasminogen activator inhitor-1, tumor necrotic factor (TNF-α), nuclear factor (NF)-κB] and the cellular level (CD40+ cells) were markedly higher in AMI(S) than in AMI(T) animals (all p<0.001). Fibrosis biomarkers at the protein level (α-smooth muscle actin, transforming growth factor-β) and Sirius-red staining were notably higher in AMI(S) than in AMI(T) animals (all p<0.03). Antioxidant biomarkers at protein or transcription levels (heme oxygenase-1, quinone oxidoreductase-1, glutathione reductase, glutathione peroxidase) were significantly higher in AMI(S) than in AMI(T) animals (all p<0.01). Protein expressions of ERK1, p38 MAPK and Akt were markedly increased in AMI(S) compared to AMI(T) animals (all p<0.001). Significantly aggravated LV infarction and remodeling were noted in AMI(S) compared to AMI(T) animals, whereas LV ejection fraction was markedly decreased in AMI(S) compared to AMI(T) animals (all p<0.001).

CONCLUSIONS

Intra-coronary administration of tacrolimus attenuated inflammation and MAPK signaling, limited infarct size, and preserved LV function.

Comparison of the clinical application of reactive oxygen species and inflammatory markers in patients with endocarditis

INTRODUCTION

Infective endocarditis (IE) is still connected with high operative mortality. Inflammatory markers are commonly used in monitoring patient clinical condition. Respiratory burst and reactive oxygen species (ROS) are the main way of pathogen elimination. Specificity of this process in the aspect of bacterial infection is the key for correlation assessment between ROS and inflammatory markers in patients with IE. In the study, assessment of ROS as a clinical indicator in IE was conducted.

MATERIAL AND METHODS

During 2007/2008 in the Cardiosurgical Clinic of the Medical University in Lodz there were 20 patients operated on for IE. The examined population consisted of 13 men and 7 women, aged from 23 to 74 years. Inflammatory markers - leukocytosis (WBC), C-reactive protein (CRP), procalcitonin (PCT) and erythrocyte sedimentation rate (ESR) - were assessed preoperatively, on the 3(rd), 7(th), 12(th) and 21(st) day. Simultaneously, with the second venous blood sample chemiluminescence (luminal enhanced whole blood chemiluminescence) was carried out and used to assess ROS production. The results were analyzed statistically.

RESULTS

Positive correlation between ESR, CRP and ROS in the preoperative period was confirmed. An increase in ROS and a statistically significant increase in inflammatory markers on the 3(rd) day were observed. The ROS normalized on the 12(th) day. Marked individual variability was specific for the inflammatory markers. Despite the significant decrease, not all of them achieved a normal level at the last control point.

CONCLUSIONS

Assessment of ROS seems to be a universal parameter with possible application in patients with IE.

Oxidative stress, mitochondrial permeability transition pore opening and cell death during hypoxia-reoxygenation in adult cardiomyocytes

Reactive oxygen species production is necessary to induce cell death following hypoxia/reoxygenation but the effect of reactive oxygen species produced during hypoxia on mitochondrial permeability transition pore (mPTP) opening and cell death is not established. Here we designed a model of hypoxia/reoxygenation in isolated cardiomyocytes measuring simultaneously reactive oxygen species production, mPTP opening and cell death in order (i) to establish a causal relationship between them, and (ii) to investigate the roles of various reactive oxygen species in mPTP opening. The percentage of cardiomyocytes exhibiting mPTP opening during reoxygenation increased with the duration of hypoxia. Antioxidants increased the time to mPTP opening when present during hypoxia but not at reoxygenation. This was associated with a drop in hydroxyl radical and hydrogen peroxide during hypoxia and the first minutes of reoxygenation. The increase in time to mPTP opening was accompanied by an improvement in cell viability reflected by maintenance of superoxide production at reoxygenation. Cyclosporin A delayed both the time to mPTP opening and cell death despite maintenance of reactive oxygen species production during hypoxia. These findings demonstrate that reactive oxygen species production precedes mPTP opening and that reactive oxygen species produced during hypoxia, particularly hydroxyl radicals and hydrogen peroxide, are necessary to induce mPTP opening which depends on hypoxia duration.

General oxidative stress during doxorubicin-induced cardiotoxicity in rats: absence of cardioprotection and low antioxidant efficiency of alpha-lipoic acid

To evaluate the effects of alpha-lipoic acid (AL) in a model of doxorubicin (DOX)-induced cardiotoxicity, male Wistar rats were treated with DOX (1 mg/kg/d; 10 d) in combination or not with AL (50 mg/kg/d; 15 d). Plasma oxidative stress was determined by hydroperoxides (ROOH) and the ascorbyl radical/ascorbate ratio. One and two months later, the functional parameters of the hearts were determined in vivo by catheterization and cardiac oxidative stress was assessed by malonedialdehyde (MDA) and O₂*⁻ (dihydroethidium fluorescence) content in tissue. After two months, body weight was higher in the DOX-AL group than in DOX (+16%), but this was due to ascites. Histological liver alterations were observed in both the DOX and DOX-AL groups. Plasma ROOH concentrations decreased after 10 days of AL treatment, but were greater in both the DOX and DOX-AL groups. After two months, a decrease in the cardiac contractility index (-27% and -29%, respectively) and cardiac hypertrophy were observed in DOX and DOX-AL. These dysfunctions were associated with 1) a reduction in plasma ascorbate levels and an increase in the ascorbyl/ascorbate ratio and 2) an increase MDA and O₂*⁻ content in cardiac tissue. In conclusion, a cumulative dose of 10 mg/kg doxorubicin induced functional alterations in the heart associated with plasma and cardiac oxidative stress. The co-administration of the antioxidant compound AL had no beneficial effects in this situation.