Elevated Serum Xanthine Oxidase and Its Correlation with Antioxidant Status in Patients with Parkinson's Disease

Parkinson's disease (PD) is a neurodegenerative movement disorder associated with a loss of dopamine neurons in the substantia nigra. The diagnosis of PD is sensitive since it shows clinical features that are common with other neurodegenerative diseases. In addition, most symptoms arise at the late stage of the disease, where most dopaminergic neurons are already damaged. Several studies reported that oxidative stress is a key modulator in the development of PD. This condition occurs due to excess reactive oxygen species (ROS) production in the cellular system and the incapability of antioxidants to neutralize it. In this study, we focused on the pathology of PD by measuring serum xanthine oxidase (XO) activity, which is an enzyme that generates ROS. Interestingly, the serum XO activity of patients with PD was markedly upregulated compared to patients with other neurological diseases (ONDs) as a control. Moreover, serum XO activity in patients with PD showed a significant correlation with the disease severity based on the Hoehn and Yahr (HY) stages. The investigation of antioxidant status also revealed that serum uric acid levels were significantly lower in the severe group (HY ≥ 3) than in the ONDs group. Together, these results suggest that XO activity may contribute to the development of PD and might potentially be a biomarker for determining disease severity in patients with PD.

Shufeiya Recipe Improves Monocrotaline-Induced Pulmonary Hypertension in Rats by Regulating SIRT3/FOXO3a and Its Downstream Signaling Pathways

Pulmonary hypertension (PH) is a chronic and progressive disease caused by obstructions and functional changes of small pulmonary arteries. Current treatment options of PH are costly with patients needing long-term taking medicine. The traditional Chinese medicine (TCM) compound "Shufeiya Recipe" was used to intervene in monocrotaline- (MCT-) induced pulmonary hypertension in rats. The rats were randomly divided into the control group, model group, positive drug (Sildenafil) group, and Shufeiya Recipe low-, moderate-, and high-dose groups. The improvement effect of the Shufeiya Recipe on the mean pulmonary artery pressure (mPAP) was assessed in PH rats, and pathological staining was used to observe the pathological changes of lung tissue. The impact of the Shufeiya Recipe on oxidative stress damage in rats with pulmonary hypertension and the regulation of SIRT3/FOXO3a and its downstream signaling pathways were determined. The results showed that Shufeiya Recipe could significantly downregulate mPAP and improve lung histopathological changes; downregulate serum levels of reactive oxygen species (ROS); upregulate the concentrations of COX-1 and COX-2 and the activity of Mn-SOD; inhibit oxidative response damage; promote the protein expression of SIRT3, FOXO3a, p-PI3K, p-AKT, and p-eNOS; increase the level of expression of NO, sGC, cGMP, and PKG; and downregulate the level of protein expression of Ras, p-MEK1/2, p-ERK1/2 and c-fos. These results indicate that Shufeiya Recipe can improve MCT-induced pulmonary hypertension in rats by regulating SIRT3/FOXO3a and its downstream PI3K/AKT/eNOS and Ras/ERK signaling pathways.

Cardiorenal protection with SGLT2 inhibitors in patients with diabetes mellitus: from biomarkers to clinical outcomes in heart failure and diabetic kidney disease

Type 2 diabetes (T2D) is one of the most common causes of chronic kidney disease (CKD) and cardiovascular (CV) disease. Until recently, glycemic and BP control were the cornerstones for preventing progression of CKD and CV disease associated with T2D. However, there has been a paradigm shift in treatment since the publication of the first clinical trial demonstrating benefits of sodium glucose cotransporter 2 (SGLT2) inhibitors in 2015. SGLT2 inhibitors have been shown to reduce the risk of major adverse CV events and progression of kidney disease in the setting of T2D. However, the elucidation of mechanisms of underlying these clinical benefits is the subject of ongoing investigation. Experimental studies have shown that SGLT2 inhibitors have diverse pleiotropic effects such as modulation of neurohormones such as the renin-angiotensin-aldosterone system, increasing hematocrit, altering energy substrate use, and attenuating systemic inflammation and oxidative stress, all of which have been implicated in the CV and kidney protective effects of SGLT2 inhibitors. In this review, we highlight biomarkers linked with diabetic kidney disease and heart failure and discuss how SGLT2 inhibitor-associated changes potentially mediate the cardiorenal protection observed with these therapies.

The effects of consuming a low-fat yogurt fortified with nano encapsulated vitamin D on serum pro-oxidant-antioxidant balance (PAB) in adults with metabolic syndrome; a randomized control trial

BACKGROUND AND AIM

The current study aimed to assess the effect of fortified yogurt with nano-encapsulated vitamin D on serum pro-oxidant anti-oxidant balance (PAB) in adults with or without metabolic syndrome.

METHODS

In a quadruple blind clinical trial study, 139 adults with an age range of 30-50 years were randomly selected to receive either 1500 IU nano-encapsulated vitamin D fortified yogurt or placebo for ten weeks. Before and after the intervention period, blood sample was taken to determine the serum levels of vitamin D, pro-oxidant-antioxidant balance (PAB), and high-sensitivity C-reactive protein (hs-CRP). The laboratory tests were checked at baseline and at the end of the treatment.

RESULTS

Serum vitamin D increased significantly, from 14.47 ± 6.07 ng/mL to 21.39 ± 6.54 ng/mL (P < 0.001) after ten weeks in the intervention group. Serum hs-CRP and PAB were significantly lower following consumption period in intervention group [1.95(0.4-8.15) g/dL vs. 1.35(0.25-3.62) g/dL; P = 0.013] and (135.19 ± 42.4 HK vs. 115.39 ± 44.69) HK; P = 0.018] respectively. There were no significant differences between the intervention and control groups regarding weight and BMI at the end of the intervention period (p > 0.05).

CONCLUSION

Low-fat yogurt fortified with nano-encapsulated vitamin D was found to reduce serum PAB levels in adults with metabolic syndrome.

PRACTICAL APPLICATION

The findings of the present study indicated that a low-fat yogurt fortified with 1500 IU nano-encapsulated vitamin D for ten weeks, leads to a significant reduction in serum hs-CRP and PAB concentrations highlighted the anti-inflammatory/anti-oxidative effect of vitamin D.

Association between Preoperative Long-Chain Polyunsaturated Fatty Acids and Oxidative Stress Immediately after Total Knee Arthroplasty: A Pilot Study

Quadriceps muscle atrophy following total knee arthroplasty (TKA) can be caused by tourniquet-induced ischemia–reperfusion (IR) injury, which is often accompanied by oxidative stress and inflammatory responses. n-3 long-chain polyunsaturated fatty acids (LCPUFAs), such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), exert antioxidant and anti-inflammatory effects against IR injury, whereas n-6 LCPUFAs, particularly arachidonic acid (AA), exhibit pro-inflammatory effects and promote IR injury. This study aimed to examine whether preoperative serum EPA + DHA levels and the (EPA + DHA)/AA ratio are associated with oxidative stress immediately after TKA. Fourteen eligible patients with knee osteoarthritis scheduled for unilateral TKA participated in this study. The levels of serum EPA, DHA, and AA were measured immediately before surgery. Derivatives of reactive oxygen metabolites (d-ROMs) were used as biomarkers for oxidative stress. The preoperative serum EPA + DHA levels and the (EPA + DHA)/AA ratio were found to be significantly negatively correlated with the serum d-ROM levels at 96 h after surgery, and the rate of increase in serum d-ROM levels between baseline and 96 h postoperatively. This study suggested the preoperative serum EPA + DHA levels and the (EPA + DHA)/AA ratio can be negatively associated with oxidative stress immediately after TKA.

The evaluation of oxidative stress parameters in breast and colon cancer

Our aim in this study was to investigate the relationship between serum ischemia modified albumin (IMA) levels with oxidative stress parameters [protein carbonyl (PCO), advanced protein oxidation products (AOPPs), malondialdehyde (MDA), total nitric oxide (NOx), prooxidant-antioxidant balance (PAB), and ferric reducing of antioxidant power (FRAP)] in breast cancer (BC) and colon cancer (CC).In total, 90 patients undergoing surgical treatment for BC (n = 45) or CC (n = 45) and 35 healthy controls were included in this cross-sectional study.The serum PCO, AOPPs, MDA, NOx, PAB, and IMA levels were all statistically significantly higher in the cancer patients than in the control group. MDA, NOx, and PAB levels were significantly lower in the BC group than in the CC group. FRAP values were statistically significantly lower in both the CC group and the BC group compared to the control. IMA showed a weak positive correlation with CA-19.9 (r = 0.423 P = .007) but a moderate positive correlation with tumor size in the CC group. IMA showed a positive correlation with metastasis, grade, and HER2 and a negative correlation with ER and PR in the BC group.Oxidative stress is a key player in the development of solid malignancies. Cancer development is a multistage process, and oxidative stress caused by the production of ROS/RNS in the breast and colon may predispose individuals to BC and CC. Patients with BC and CC had an impaired oxidative/antioxidant condition that favored oxidative stress. The ROC analysis indicated that IMA sensitivity above 80% could be used as a secondary biomarker in diagnosis.

Hyperuricemia and the Risk of Heart Failure: Pathophysiology and Therapeutic Implications

The association between hyperuricemia and cardiovascular disease (CVD) has been reported and studied in the past two decades. Xanthine oxidase (XO) induced uric acid (UA) serves as a risk factor and has the independent prognostic and functional impact of heart failure (HF), but whether it plays a positive role in the pathogenesis of HF has remained unclear. Growing evidence suggest the up-regulated XO avtivity and increased production of free oxygen radical (ROS) correspondingly are the core pathogenesis of HF with hyperuricemia, which results in a whole cluster of pathophysiologic cardiovascular effects such as oxidative stress, endothelial dysfunction, vascular inflammation, left ventricular (LV) dysfunction as well as insulin resistance (IR). The use of XO inhibition represents a promising therapeutic choice in patients with HF due to its dual effect of lowering serum UA levels as well as reducing ROS production. This review will discuss the pathophysiologic mechanisms of hyperuricemia with HF, the targeted therapeutic interventions of UA lowering therapies (ULT) with XO inhibition and mechanism underlying beneficial effects of ULT. In addition, the review also summarizes current evidence on the role of ULT in HF and compares CV risk between allopurinol and febuxostat for practical and clinical purposes. Guidelines and implementation of CV risk management in daily practice will be discussed as well.

Critical Evaluation of the Interaction of Reactive Oxygen and Nitrogen Species with Blood to Inform the Clinical Translation of Nonthermal Plasma Therapy

Non-thermal plasma (NTP), an ionized gas generated at ambient pressure and temperature, has been an emerging technology for medical applications. Through controlled delivery of reactive oxygen and nitrogen species (ROS/RNS), NTP can elicit hormetic cellular responses, thus stimulating broad therapeutic effects. To enable clinical translation of the promising preclinical research into NTP therapy, a deeper understanding of NTP interactions with clinical substrates is profoundly needed. Since NTP-generated ROS/RNS will inevitably interact with blood in several clinical contexts, understanding their stability in this system is crucial. In this study, two medically relevant NTP delivery modalities were used to assess the stability of NTP-generated ROS/RNS in three aqueous solutions with increasing organic complexities: phosphate-buffered saline (PBS), blood plasma (BP), and processed whole blood. NTP-generated RNS collectively (NO2 -, ONOO-), H2O2, and ONOO- exclusively were analyzed over time. We demonstrated that NTP-generated RNS and H2O2 were stable in PBS but scavenged by different components of the blood. While RNS remained stable in BP after initial scavenging effects, it was completely reduced in processed whole blood. On the other hand, H2O2 was completely scavenged in both liquids over time. Our previously developed luminescent probe europium(III) was used for precision measurement of ONOO- concentration. NTP-generated ONOO- was detected in all three liquids for up to at least 30 seconds, thus highlighting its therapeutic potential. Based on our results, we discussed the necessary considerations to choose the most optimal NTP modality for delivery of ROS/RNS to and via blood in the clinical context.

Evaluation of environmental effects of heavy metals on biochemical profile and oxidative stress among children at brick kiln sites

The present study was designed to study the health risks among children living at brick kiln industries. A survey was conducted, questionnaires were filled out, and demographic data was collected from Punjab, Pakistan. Heavy metals burden and BMI were calculated, hematological and enzyme analysis, comet assay and hormonal ELISA were performed. The results showed decreased BMI, RBC count and hematocrit in the exposed group. Nickel, cadmium, zinc and chromium concentrations in whole blood were detected among exposed children. Antioxidant enzymes and growth hormone concentration decreased, while reactive oxygen species and cortisol level increased in the exposed group. The comet assay findings showed decreased percentage DNA in the head and increased in the tail region among exposed group. It was concluded that children living at brick kiln sites experienced decreased BMI, altered antioxidant enzymes status and hormone levels and cellular DNA damage that pose a major threat on child health.

Evaluation of ABO blood group in subjects with CVD risk factors in a population sample from northeastern Iran

BACKGROUND AND AIMS

The ABO blood group system is a genetic polymorphism which can affect the clearance of von Willebrand factor. We aimed to assess the levels of newer biomarkers of cardiovascular disease (CVD) risk; pro-oxidant-antioxidant balance (PAB), high sensitivity C-reactive protein (hs-CRP) and anti-heat-shock protein27 (anti-Hsp27) antibody titers in subjects with various blood groups (A, B, AB and O) and with or without traditional CVD risk factors.

METHODS

The cross-sectional study comprised 6910 subjects. Antigen-antibody agglutination was evaluated by the slide test method for identification of ABO blood groups.

RESULTS

Among three markers, only Serum anti-Hsp27 titers significantly differed between the four blood groups and showed the highest and lowest values in AB and O blood groups (0.26 ± 0.22 and 0.23 ± 0.18 OD, respectively; P < 0.05). Serum anti-Hsp27 was higher in individuals with an AB blood group with metabolic syndrome (MetS), dyslipidemia, hypertension (HTN) and obesity and it was lower in subjects with O blood group; though, two other biomarkers, serum PAB and hs-CRP, were not significantly different between the ABO blood groups. However, they were not different among blood groups in participants with or without diabetes mellitus (DM) (P > 0.05).

CONCLUSION

Individuals with an AB blood group and high levels of anti-Hsp27 antibody titers may be predisposed to CVDs that can be mediated through the traditional CVD risk factors among middle-aged subjects from northeastern Iran. The fact that differences in anti Hsp27 are only found in the subgroup with other risk factors suggest that the difference between ABO blood groups is a consequence rather than a cause.

Oxidative stress in Vitiligo patients and administration of Munzij and Mushil therapy, a poly herbal Unani formulation - hospital-based study

Background Vitiligo, a skin disorder is viewed as a multifactorial process with major role of reactive oxygen species in concert to destroy or incapacitate melanocytes. In Unani system of medicine the treatment of Bars (Vitiligo) starts with removal of harmful materials from the body with Munzij and Mushil (MM), a poly herbal Unani formulation. Methods Herein, oxidative stress related parameters as MDA, SOD, GPx and CAT have been estimated in the 21 clinically diagnosed Vitiligo in-patients and subsequently these parameters were evaluated during and after administration of MM therapy and compared with 21 healthy subjects. Results There was significant difference in the parameters viz., SOD (p<0.001) and CAT (p<0.005) activity at the baseline with no statistical significant difference in MDA and GPx activity among Vitiligo subjects and controls. After MM therapy there was no statistical significant difference among the values of these parameters in Vitiligo subjects. Conclusions The results suggest that there is imbalance in the oxidant-antioxidant status of Vitiligo subjects and the MM therapy is not found to significantly change the levels of oxidative stress related parameters.

Lymphocyte activation after a high-intensity street dance class

Intense dance training leads to inflammation, which may impair the health and performance of the practitioners. Herein, we evaluate the effect of a single street dancing class on the profile of muscle enzymes, lymphocyte activation, and cell surface CD62L expression. We also investigated the correlation between muscle enzymes, adhesion molecules, and lymphocyte activation in dancers. Fifteen male participants (mean ± standard error: age 22.4 ± 1.08 years, body mass index 24.8 ± 0.69 kg/m2, body fat 12.3 ± 1.52%), who were amateur dancers, had blood samples collected previously and subsequent to a high-intensity street dance class. After the class, dancers showed an increase in total lymphocyte count (2.0-fold), creatine kinase (CK)-NAC (4.87%), and CK-MB (3.36%). We also observed a decrease (2.5-fold) in reactive oxygen species (ROS) produced by lymphocytes, under phorbol myristate acetate-stimulated environments. Following the dance class, CD62L expression in lymphocytes decreased (51.42%), while there was a negative correlation between the intensity of the exercise and CD62L expression (r = -0.73; p = 0.01). Lymphocytes were less responsive to stimuli after a single bout of street dancing, indicating transient immunosuppression.

Effects of high-intensity interval exercise under hyperoxia on HSP27 and oxidative stress responses

Hypoxia in working muscles during exercise may be associated with increased oxidative stress. Inhalation of hyperoxic gas diminishes the hypoxia within working muscles during exercise. Exposure to hyperoxia increases the expression of the antioxidant HSP27. We investigated the effects of acute high-intensity interval exercise (HIE) under hyperoxia on HSP27 levels and oxidative stress responses. Eight male subjects participated in two experiments: 1) normoxic HIE (NHIE) and 2) hyperoxic (60 % oxygen) HIE (HHIE). HIE consisted of four 30-s all-out cycling bouts with 4-min rest between bouts. Levels of serum oxidative stress markers (d-ROMs and LPO), HSP27, BAP, IL-6, and TNF-α significantly increased after both trials. The HIE-induced changes in d-ROMs, LPO, and HSP27 levels were significantly lower in the HHIE trial than in the NHIE trial. These findings suggest that inhaling hyperoxic gas during exercise might diminish oxidative stress induced by all-out HIE.

Novel biomarkers of oxidative stress as predictive indicators of neurological outcome after out-of-hospital cardiopulmonary arrest

AIM

Among patients of out-of-hospital cardiopulmonary arrest (OHCPA), only 6% resume their pre-OHCPA social life. The prediction of neurological outcome immediately after the return of spontaneous circulation (ROSC) is urgently needed in OHCPA patients. Novel biomarkers, biological antioxidant potential (BAP), and diacron-reactive oxygen metabolites (d-ROM) are potential predictors of neurological outcome after OHCPA. This study was conducted to evaluate the utility of BAP and d-ROM in the prediction of patient outcomes after OHCPA.

METHODS

Blood samples were collected immediately after OHCPA patients were admitted to our hospital between May 2011 and June 2013. BAP and d-ROM concentrations were measured with the simple equipment FRAS4 ™ (Wismerll, Italy). Their association with favorable (cerebral performance category [CPC], 1 and 2) and unfavorable (CPC 3-5) clinical outcomes was compared. BAP and d-ROM values from 23 normal healthy volunteers (HV) were used as controls.

RESULTS

Overall, 152 OHCPA patients were included, and 26 patients achieved ROSC. Eleven died during hospitalization were allocated a CPC of 5 and remaining patients were discharged or transported (CPC 1: n = 4; CPC 2: n = 6; CPC 3: n = 3; CPC 4: n = 2; CPC 5: n = 11). The receiver operating characteristics curve of d-ROM and BAP for predicting survival 28 days after OHCPA was 0.596 and 0.834, respectively. Patients without ROSC had significantly higher BAP than HV and patients with ROSC (p < 0.001). A significant correlation was evident between BAP and the time to ROSC (r = 0.641, p < 0.01).

CONCLUSION

Oxidative stress, indicated by BAP on admission, strongly correlated with the neurological outcome after OHCPA.

Acute phase proteins and markers of oxidative status in water buffalos during the transition from late pregnancy to early lactation

The transition period, from pregnancy to lactation, implies comprehensive metabolic and endocrine changes including a systemic inflammatory reaction and oxidative stress around calving in dairy cows. The aim of the present study was a longitudinal characterization of the serum concentration of acute phase proteins (APP), i.e., haptoglobin (Hp), serum amyloid A (SAA) and acidic glycoprotein (AGP), as well as of markers for oxidative stress in another large dairy animal, i.e. water buffalo, during the transition from late pregnancy to early lactation. As indicators of oxidative status, derivatives of reactive oxygen metabolites (dROM), ferric reducing ability (FRAP), thiobarbituric acid reactive substances (TBARS), and advanced oxidation protein products (AOPP) were determined in serum. Indicators for metabolic stress included nonesterified fatty acids (NEFA), ß-hydroxybutyrate (BHB) and adiponectin. Bovine specific ELISA methods for Hp and adiponectin were adapted and validated for their application to water buffalo samples. Blood samples were collected weekly from 11 pluriparous water buffalo cows (lactation number 4.6 ± 1.6; daily milk yield 9.0 ± 1.9 kg; means ± SD) from 6 weeks (wk) ante partum (ap) until 8 wk post partum (pp). The maximum concentrations of Hp were observed in wk 1 pp, followed by a decrease towards values lower than before calving starting from wk 3 pp. The concentrations of SAA also peaked in wk 1 pp and then returned to basal values. The AGP serum concentrations increased suddenly from the first to the second wk pp and remained elevated for all the observation period. Indicators of oxidative status which changed in concentration during the transition period were dROM, AOPP and the oxidative stress index (OSi) (dROM/FRAP ratio). Briefly, dROM and AOPP values were lower pp as compared to ap, and OSi was largely following the pattern of dROM due to the constant FRAP values. The TBARS values did not change during the observation period. From the metabolic indicators, adiponectin was not changing with time, whereas greater NEFA and BHB values were observed ap than pp. The time course of NEFA and of some indicators for oxidative status (dROM, OSi and AOPP) point to greater metabolic load in late pregnancy as compared with the first wk of lactation - contrary to the common situation in dairy cows. Both BHB and NEFA values remained below the thresholds applied for dairy cows to define subclinical or clinical ketosis, thus indicating that the buffaloes included in this study were not under metabolic stress. The increase in concentration of the APP around calving supports the concept that an inflammatory reaction is a physiological epiphenomenon of the onset of lactation in water buffalos that is independent of metabolic stress.

Perioperative reactive oxygen species in infants with biliary atresia: A retrospective observational study

Biliary atresia (BA) is a devastating cholestatic disorder of infants that presents during the first several months after birth due to an idiopathic obstruction to the bile flow. Without prompt diagnosis, Kasai portoenterostomy, and deliberate follow-ups, the resulting cholestasis leads to progressive hepatic failure. Oxidative stress is an abnormal phenomenon inside cells or tissues caused by a disturbance in the reactive oxygen species (ROS). We aimed to measure perioperative ROS in BA patients.Data are presented as median (25th, 75th percentiles). We evaluated 15 BA patients (age 55 [48, 69] days) and measured ROS; serum superoxide dismutase (SOD), urinary 8-iso prostaglandin F2α (8-iso-PGF2α) and 8-hydroxy-2'-deoxyguanosine (8-OHdG) preoperatively and 30 days later to compare values with serum liver function tests and histologic grades of liver cholestasis. For compared BA patients, 4 normal subjects as control group (age 55 [27, 75] days) measured ROS and serum liver function tests.In BA patients, the preoperative serum SOD was 6.1 IU/mL (4.7, 7.2), urinary 8-iso-PGF2α was 1969 pg/mg Cre (1697, 2374), and urinary 8-OHdG was 37.1 ng/mg Cre (33.1, 53.7). At the postoperative day 30, the serum SOD was 5.2 IU/mL (4.2, 6.7), urinary 8-iso-PGF2α was 1761 pg/mg Cre (1256, 3036), and urinary 8-OHdG was 42.1 ng/mg Cre (29.65, 72.64). In ROS, there were no significant differences between the 2 periods. In control group, urinary 8-iso-PGF2α was significantly lower than that in preoperative BA patient group. However, other ROS were not significant differences between control group and BA patient group. The concentration of urinary 8-iso-PGF2α was positively correlated with total bilirubin and direct bilirubin levels (preoperatively: r = 0.6921, P = .0042 and r = 0.6639, P = .007, postoperatively: r = 0.6036, P = .0172 and r = 0.6464, P = .0092, respectively). The preoperative ROS were not correlated with histologic grades of liver cholestasis. Various factors such as liver inflammation, lipid malabsorption, and tissue disorders due to jaundice might affect the antioxidant activity and elevated urinary 8-iso-PGF2α. However, at least until 30 days later, urinary 8-OHdG as oxidative DNA damage might persist after the operation whether the cholestasis improved or not.

Endogenous Deficiency of Glutathione as the Most Likely Cause of Serious Manifestations and Death in COVID-19 Patients

Higher rates of serious illness and death from coronavirus SARS-CoV-2 (COVID-19) infection among older people and those who have comorbidities suggest that age- and disease-related biological processes make such individuals more sensitive to environmental stress factors including infectious agents like coronavirus SARS-CoV-2. Specifically, impaired redox homeostasis and associated oxidative stress appear to be important biological processes that may account for increased individual susceptibility to diverse environmental insults. The aim of this Viewpoint is to justify (1) the crucial roles of glutathione in determining individual responsiveness to COVID-19 infection and disease pathogenesis and (2) the feasibility of using glutathione as a means for the treatment and prevention of COVID-19 illness. The hypothesis that glutathione deficiency is the most plausible explanation for serious manifestation and death in COVID-19 patients was proposed on the basis of an exhaustive literature analysis and observations. The hypothesis unravels the mysteries of epidemiological data on the risk factors determining serious manifestations of COVID-19 infection and the high risk of death and opens real opportunities for effective treatment and prevention of the disease.

Quantification of mitochondrial DNA damage and copy number in circulating blood of patients with systemic sclerosis by a qPCR-based assay

Background

Although not fully understood, oxidative stress has been implicated in the pathogenesis of different autoimmune diseases such as systemic sclerosis. Accumulating evidence indicates that oxidative stress can induce mitochondrial DNA (mtDNA) damage and variations in mtDNA copy number (mtDNAcn).

Objective

The aim of this study was to explore mtDNAcn and oxidative DNA damage byproducts in peripheral blood of patients with systemic sclerosis and healthy controls.

Methods

Forty six patients with systemic sclerosis and forty nine healthy subjects were studied. Quantitative real-time PCR used to measure the relative mtDNAcn and the oxidative damage (oxidized purines) of each sample.

Results

The mean mtDNAcn was lower in patients with systemic sclerosis than in healthy controls whereas the degree of mtDNA damage was significantly higher in cases as compared to controls. Moreover, there was a negative correlation between mtDNAcn and oxidative DNA damage.

Study limitations

The lack of simultaneous analysis and quantification of DNA oxidative damage markers in serum or urine of patients with systemic sclerosis and healthy controls.

Conclusion

These data suggest that alteration in mtDNAcn and increased oxidative DNA damage may be involved in the pathogenesis of systemic sclerosis.

Integrating Flexible Electrochemical Sensor into Microfluidic Chip for Simulating and Monitoring Vascular Mechanotransduction

As an interface between the blood flow and vessel wall, endothelial cells (ECs) are exposed to hemodynamic forces, and the biochemical molecules released from ECs-blood flow interaction are important determinants of vascular homeostasis. Versatile microfluidic chips have been designed to simulate the biological and physiological parameters of the human vascular system, but in situ and real-time monitoring of the mechanical force-triggered signals during vascular mechanotransduction still remains a significant challenge. Here, such challenge is fulfilled for the first time, by preparation of a flexible and stretchable electrochemical sensor and its incorporation into a microfluidic vascular chip. This allows simulating of in vivo physiological and biomechanical parameters of blood vessels, and simultaneously monitoring the mechanically induced biochemical signals in real time. Specifically, the cyclic circumferential stretch that is actually exerted on endothelium but is hard to reproduce in vitro is successfully recapitulated, and nitric oxide signals under normal blood pressure, as well as reactive oxygen species signals under hypertensive states, are well documented. Here, the first integration of a flexible electrochemical sensor into a microfluidic chip is reported, therefore paving a way to evaluate in vitro organs by built-in flexible sensors.

Cellular Turnover: A Potential Metabolic Rate-Driven Mechanism to Mitigate Accumulation of DNA Damage

Oxidative stress, the imbalance of reactive oxygen species and antioxidant capacity, may cause damage to biomolecules pivotal for cellular processes (e.g., DNA). This may impair physiological performance and, therefore, drive life-history variation and aging rate. Because aerobic metabolism is supposed to be the main source of such oxidative risk, the rate of oxygen consumption should be positively associated with the level of damage and/or antioxidants. Empirical support for such relationships remains unclear, and recent considerations suggest even a negative relationship between metabolic rate and oxidative stress. We investigated the relationship between standard metabolic rate (SMR), antioxidants, and damage in blood plasma and erythrocytes for 35 grass snakes (Natrix natrix). Reactive oxygen metabolites (dROMs) and nonenzymatic antioxidants were assessed in plasma, while two measures of DNA damage and the capacity to neutralize H₂O₂ were measured in erythrocytes. Plasma antioxidants showed no correlation to SMR, and the level of dROMs was positively related to SMR. A negative relationship between antioxidant capacity and SMR was found in erythrocytes, but no association of SMR with either measure of DNA damage was detected. No increase in DNA damage, despite lower antioxidant capacity at high SMR, indicates an upregulation in other defense mechanisms (e.g., damage repair and/or removal). Indeed, we observed a higher frequency of immature red blood cells in individuals with higher SMR, which indicates that highly metabolic individuals had increased erythrocyte turnover, a mechanism of damage removal. Such DNA protection through upregulated cellular turnover might explain the negligible senescence observed in some ectotherm taxa.

Factors associated with high oxidative stress in patients with type 2 diabetes: a meta-analysis of two cohort studies

OBJECTIVE

Our objective is to identify the potential factors associated with serum Diacron's reactive oxygen metabolites test (D-ROM) levels of patients with type 2 diabetes mellitus (T2DM) by conducting cross-sectional and longitudinal analyses in two large cohorts and further strengthening these results by performing a meta-analysis.

METHODS

Serum D-ROM concentrations were measured in 1045 and 1101 patients with T2DM from two independent cohort studies from Germany at baseline and repeatedly 3-4 years later. The cross-sectional and longitudinal associations of various potential determinants with D-ROM levels were assessed with a backwards selection algorithm in multivariable adjusted models.

RESULTS

In the meta-analysis of the cross-sectional analysis, female sex, low education, obesity, smoking, high total cholesterol, hemoglobin A_1c ≥7%, no diabetes medication, a history of myocardial infarction, heart failure, a history of cancer and C reactive protein levels (CRP) >3 mg/L were statistically significantly associated with increased D-ROM levels in patients with T2DM. The meta-analysis of the longitudinal analysis revealed that old age, female sex, obesity, smoking, physical inactivity, high alcohol consumption, ≥5 years since diabetes diagnosis and CRP levels between 3 mg/L and 10 mg/L were statistically significantly associated with D-ROM levels measured 3-4 years later.

CONCLUSIONS VALIDITY, LIMITATIONS AND CLINICAL APPLICABILITY

This comprehensive analysis confirmed that several modifiable risk factors are being associated with oxidative stress in patients with T2DM within an observational study design. We discuss potential prevention measures against these risk factors that might help to reduce oxidative stress and to prevent some cases of premature mortality in patients with T2DM.

Factors associated with longitudinal changes in serum concentrations of Mac-2 binding protein: A prospective 3-year observational study

BACKGROUND AND AIMS

Mac-2 binding protein (M2BP) plays an important role in cell adhesion. In a recent cross-sectional study we reported that serum M2BP concentrations may reflect silent atherosclerosis. The aim of the present prospective follow-up study was to investigate possible relationships between changes in concentrations of M2BP and other factors over a >3-year period.

METHODS AND RESULTS

The present study enrolled subjects who visited Enshu hospital from 2014 to 2015 for a periodic physical check-up and then attended for another physical check-up after >3 years (n = 174). Factors affecting changes in M2BP concentrations were investigated at both baseline and follow-up. Subjects with liver dysfunction, a history of hepatic disease, malignant neoplasm, or cardiovascular events at baseline were excluded. Univariate and multivariate regression analyses showed that changes in serum M2BP concentrations during the follow-up period were significantly associated with changes in low-density lipoprotein cholesterol (LDL-C), triglyceride, and oxidative stress marker derivatives of reactive oxygen metabolites (d-ROM) concentrations. Moreover, the increase in LDL-C was significantly greater in subjects in whom M2BP concentrations increased during the follow-up period. Logistic regression analysis with an endpoint of increased M2BP revealed that increased LDL-C was an independent determinant of an increase in M2BP during the follow-up period.

CONCLUSION

During the observation period of >3 years, serum M2BP concentrations were increased in subjects who also exhibited increases in levels of metabolic parameters, especially LDL-C, and the oxidative stress marker d-ROM. These results support that serum M2BP reflects one of the contributors to the progression of silent atherosclerosis.

Oxidative Stress Markers to Investigate the Effects of Hyperoxia in Anesthesia

Oxygen (O₂) is commonly used in clinical practice to prevent or treat hypoxia, but if used in excess (hyperoxia), it may act as toxic. O₂ toxicity arises from the enhanced formation of Reactive Oxygen Species (ROS) that exceed the antioxidant defenses and generate oxidative stress. In this study, we aimed at assessing whether an elevated fraction of inspired oxygen (FiO₂) during and after general anesthesia may contribute to the unbalancing of the pro-oxidant/antioxidant equilibrium. We measured five oxidative stress biomarkers in blood samples from patients undergoing elective abdominal surgery, randomly assigned to FiO₂ = 0.40 vs. 0.80: hydroperoxides, antioxidants, nitrates and nitrites (NO_x), malondialdehyde (MDA), and glutathionyl hemoglobin (HbSSG). The MDA concentration was significantly higher 24 h after surgery, and the body antioxidant defense lower, in the FiO₂ = 0.80 group with respect to both the FiO₂ = 0.40 group and the baseline values (p ≤ 0.05, Student’s t-test). HbSSG in red blood cells was also higher in the FiO₂ = 0.80 group at the end of the surgery. NO_x was higher in the FiO₂ = 0.80 group than the FiO₂ = 0.40 group at t = 2 h after surgery. MDA, the main end product of the peroxidation of polyunsaturated fatty acids directly influenced by FiO₂, may represent the best marker to assess the pro-oxidant/antioxidant equilibrium after surgery.

Changes in the blood redox balance during a simulated duathlon race and its relationship with athletic performance

The duathlon is an endurance multisport event that consists of sequential running, cycling, and further running. Imbalance in the redox homeostasis is associated with fatigued status and underperformance in various sports; however, there are no corresponding reports regarding the duathlon. The purpose of this study was to examine the changes in the blood redox balance during a simulated duathlon race and to determine the relationship between performance and the redox balance. Eight male triathletes participated in a simulated race, consisting of a 5-km run, 30 km cycling, and a further 5-km run, with 5 min rest between two parts to collect the blood samples. The serum levels of reactive oxygen metabolites (d-ROMs) and biological antioxidant potential (BAP) were measured and BAP/d-ROMs ratio and oxidative stress index (OSI) were calculated. The d-ROMs levels after the first Run were significantly increased compared with the levels observed before the race. Moreover, BAP levels increased significantly over the race. The BAP/d-ROMs ratio also gradually increased through the race, while the OSI was gradually decreased. In addition, a significant relationship was observed only between d-ROMs levels after the first Run and the first Run performance. These results suggest that the redox balance shifts toward reduction (antioxidation) during the duathlon race and increased oxidant potential levels are negatively correlated with performance in the early stages of the race.

Adrenic acid non-enzymatic peroxidation products in biofluids of moderate preterm infants

Oxidative stress plays an essential role in processes of signaling and damage to biomolecules during early perinatal life. Isoprostanoids and isofuranoids from the free radical-catalyzed peroxidation of polyunsaturated fatty acids (PUFAs) are widely recognized as reliable biomarkers of oxidative stress. However, their quantification is not straightforward due to high structural similarity of the compounds formed. In this work, a semiquantitative method for the analysis of adrenic acid (AdA, C22:4 n-6) non-enzymatic peroxidation products (i.e. dihomo-isoprostanes and dihomo-isofurans) was developed. The proposed ultra-performance liquid chromatography - tandem mass spectrometry (UPLC-MS/MS) method was applied to the analysis of blood plasma and urine from preterm infants providing information about AdA peroxidation.

A protective study of curcumin associated with Cr6+ induced oxidative stress, genetic damage, transcription of genes related to apoptosis and histopathology of fish, Channa punctatus (Bloch, 1793)

Ameliorative potential of curcumin against Cr⁶⁺-induced eco-toxicological manifestations was assessed in liver of exposed Channa punctatus (Actinopterygii) in six groups for 45 d; Group I as control. Group II with 3 mg/L of curcumin; group III with 7.89 mg/L of Cr⁶⁺. Groups IV, V and VI were simultaneously co-exposed with 7.89 mg/L of Cr⁶⁺ and three different curcumin concentrations, 1, 2, and 3 mg/L, respectively. In group III, SOD-CAT, GR significantly (p < 0.05) increased; decreased GSH level; elevated MN and AC frequencies; and a significant (p < 0.05) up-regulation of cat (2.72-fold), p53 (1.73-fold), bax (1.33-fold) and apaf-1 (2.13-fold) together with a significant (p < 0.05) down-regulation of bcl-2 (0.51-fold). Co-exposure significantly (p < 0.05) brought down activities of SOD-CAT, GR, raised GSH, decreased micronuclei and apoptotic frequencies along with recovery of histopathological anomalies in liver. This study establishes the protective role of curcumin against Cr⁶⁺-induced hepatotoxicity in fish.

Effect of Primary and Secondary Beads of Carbon Enterosorbent on Haematological Parameters and Oxidative Stress Development Caused by Melphalan in Rats

Background and Objectives: Side effects of anti-cancer drugs are usually accompanied by oxidative stress, including myelotoxicity. We evaluated the potential of oral highly activated micro-/macroporous carbon adsorbents (bulk density of 0.16 g/cm3, surface area calculation by Brunauer-Emmett-Teller model (SBET) > 2200 m2/g, derived from proprietary phenolic resin beads) to alleviate oxidative stress and myelotoxicity in rats. Materials and Methods: A single injection of cytostatic melphalan (L-PAM) at a dose of 4 mg/kg was used for modelling. Two forms of activated carbon were used: AC1-primary beads with the particle size range of 125-250 µm, and AC2-micronized AC1 with a mean particle size of ~1 µm. We measured haematological parameters white blood cells, red blood cells, platelet count, and haemoglobin level. Oxidative stress intensity was evaluated using the following markers: total levels of reactive oxygen species (ROS) in blood plasma; catalase activity (CAT) and pro-oxidant/antioxidant ratio in blood haemolysate samples; level of reduced glutathione (GSH) in liver tissues; oxidative modification of proteins, OPM (APHD, aldehyde-dinitrophenylhydrazone derivatives and KPHD, ketone dinitrophenylhydrazone derivatives) and malonic dialdehyde (MDA) in blood plasma and liver samples. Results: AC2 administration promoted significant myeloprotective effect: 1.5-fold increase in leukocytes, 2-fold in neutrophils, 1.5-fold in lymphocytes, and 1.23-fold in platelet count compared to the experimental Melphalan Group. At the same time, AC1 administration resulted in a slight increase in haematological parameters. Both ACs positively corrected important, but diverse, components of oxidative stress. They significantly reduced oxidative modification of blood and liver proteins (especially the AC1 form), normalized the level of reduced glutathione, pro-oxidant/antioxidant ratio and other markers. For some markers, such as ROS production in blood plasma, the use of enterosorbents resulted in non-significant a shift towards normal parameters. Conclusions: Oral activated carbon adsorbents reduce oxidative stress intensity and myelotoxicity; they can be promising means to combat the adverse effects of chemotherapy in clinical practice.

Effects of Blood Flow Restriction Training with Protein Supplementation on Muscle Mass And Strength in Older Men

Blood flow restriction (BFR) training has been shown to induce favorable changes in muscle mass and strength with a considerably low training load (20 - 30% 1RM). However, it has never been evaluated if an additional post-exercise protein supplementation enhances the effects of this training regimen. Thirty healthy older men (60.1 ± 7.6 years) were enrolled in the 8-week intervention and randomly allocated to one of the following groups: low-load BFR training with protein (collagen hydrolysate) supplementation (BFR-CH), low-load BFR training with placebo (BFR-PLA), or a control group without training, but with protein supplementation (CON). Muscle cross-sectional area (CSA), muscle strength, circulating reactive oxygen species and IGF-1 were measured before and after the intervention. Muscle CSA increased in both BFR-CH and BFR-PLA groups by 6.7 ± 3.2 % (p < 0.001) and 5.7 ± 2.7 % (p < 0.001) respectively. No significant changes were observed in the CON group (1.1 ± 1.7 %, p = 0.124). Evaluation of isometric strength (p = 0.247), insulin-like growth factor 1 (p = 0.705) and the production of reactive oxygen species (p^t1 = 0.229; p^t2 = 0.741) revealed no significant interaction effect but a significant long-term time effect (p < 0.001). Our results demonstrate that BFR training is an effective alternative for increasing muscle CSA in older men. Although there was a trend towards greater muscle mass adaptations in the BFR-CH group, these findings showed no statistical significance. Further research with larger sample sizes is needed to confirm these results.

Glutathione infusion before primary percutaneous coronary intervention: a randomised controlled pilot study

OBJECTIVE

In the setting of reperfused ST-elevation myocardial infarction (STEMI), increased production of reactive oxygen species (ROS) contributes to reperfusion injury. Among ROS, hydrogen peroxide (H₂O₂) showed toxic effects on human cardiomyocytes and may induce microcirculatory impairment. Glutathione (GSH) is a water-soluble tripeptide with a potent oxidant scavenging activity. We hypothesised that the infusion of GSH before acute reoxygenation might counteract the deleterious effects of increased H₂O₂ generation on myocardium.

METHODS

Fifty consecutive patients with STEMI, scheduled to undergo primary angioplasty, were randomly assigned, before intervention, to receive an infusion of GSH (2500 mg/25 mL over 10 min), followed by drug administration at the same doses at 24, 48 and 72 hours elapsing time or placebo. Peripheral blood samples were obtained before and at the end of the procedure, as well as after 5 days. H₂O₂ production, 8-iso-prostaglandin F2α (PGF2α) formation, H₂O₂ breakdown activity (HBA) and nitric oxide (NO) bioavailability were determined. Serum cardiactroponin T (cTpT) was measured at admission and up to 5 days.

RESULTS

Following acute reperfusion, a significant reduction of H₂O₂ production (p=0.0015) and 8-iso-PGF2α levels (p=0.0003), as well as a significant increase in HBA (p<0.0001)and NO bioavailability (p=0.035), was found in the GSH group as compared with placebo. In treated patients, attenuated production of H₂O₂ persisted up to 5 days from the index procedure (p=0.009) and these changes was linked to those of the cTpT levels (r=0.41, p=0.023).

CONCLUSION

The prophylactic and prolonged infusion of GSH seems to determine a rapid onset and persistent blunting of H₂O₂ generation improving myocardial cell survival. Nevertheless, a larger trial, adequately powered for evaluation of clinical endpoints, is ongoing to confirm the current finding.

TRIAL REGISTRATION NUMBER

EUDRACT 2014-00448625; Pre-results.

Alcoholic Hepatitis: A Review

Alcoholic liver disease (ALD) represents a spectrum of injury, ranging from simple steatosis to alcoholic hepatitis to cirrhosis. Regular alcohol use results in fatty changes in the liver which can develop into inflammation, fibrosis and ultimately cirrhosis with continued, excessive drinking. Alcoholic hepatitis (AH) is an acute hepatic inflammation associated with significant morbidity and mortality that can occur in patients with steatosis or underlying cirrhosis. The pathogenesis of ALD is multifactorial and in addition to genetic factors, alcohol-induced hepatocyte damage, reactive oxygen species, gut-derived microbial components result in steatosis and inflammatory cell (macrophage and neutrophil leukocyte) recruitment and activation in the liver. Continued alcohol and pro-inflammatory cytokines induce stellate cell activation and result in progressive fibrosis. Other than cessation of alcohol use, medical therapy of AH is limited to prednisolone in a subset of patients. Given the high mortality of AH and the progressive nature of ALD, there is a major need for new therapeutic intervention for this underserved patient population.

3-(4-Chlorophenylselanyl)-1-methyl-1H-indole promotes recovery of neuropathic pain and depressive-like behavior induced by partial constriction of the sciatic nerve in mice

3-(4-Chlorophenylselanyl)-1-methyl-1H-indole (CMI) is an organoselenium compound that presents antioxidant activity, antinociceptive, anti-inflammatory and antidepressive-like effect in mice in previous studies conducted by our research group. In this study, we evaluate the anti-allodynic, anti-hyperalgesic and antidepressant-like effects of CMI on partial sciatic nerve ligation (PSNL) in male adult Swiss mice (25-35 g) as well as the involvement of oxidative stress in these effects. Mice underwent PSNL surgery and after 4 weeks they were treated with CMI (10 mg/kg, intragastric route [i.g.]) or vehicle. The treatment with CMI (10 mg/kg, i.g.) reversed the increased the percentage of response to Von-Frey Hair (VFH) stimulation, decreased the latency time to nociceptive response in the hot-plate test, increased immobility time in the forced swimming test (FST) and decreased groomings activity in the splash test, all induced by PSNL. Additionally, CMI also reversed increased the levels of reactive oxygen species (ROS) and lipid peroxidation in cortex and hippocampus and plasmatic levels of corticosterone in mice, induced by PSNL. Results demonstrate that CMI reversed behavioral and biochemical alterations in the dyad pain-depression induced by PSNL and possibly modulation of oxidative system.

The emerging roles of eryptosis in liver diseases

Erythrocytes undergo programmed cell death, similar to apoptosis, known as eryptosis. This process is a result of several factors including hyperosmolarity, oxidative stress, and exposure to xenobiotics, and is characterized by the breakdown of membrane phospholipid asymmetry, the clustering of band 3, and the generation of red blood cell-derived microparticles. Under pathological conditions, the liver is the primary site of erythrocyte clearance and plays an important role in iron recycling. Phosphatidylserine exposure and band-3 clustering on eryptotic erythrocytes represent mainly pro-phagocytic signals. Further, the percentage of eryptotic erythrocytes is enhanced in the circulating blood of patients with hepatic failure, hyperbilirubinemia, and nonalcoholic steatohepatitis. In this review, we concentrate on recent progress regarding the pathophysiological roles of eryptosis in liver diseases.

Trace Metals in the Freshwater Fish Cyprinus carpio: Effect to Serum Biochemistry and Oxidative Status Markers

Interactions between trace metals, serum biochemical parameters, and oxidative status markers were observed. Freshwater fish Cyprinuscarpio blood samples (n = 38) were collected at the beginning of May (n = 19) and at the end of July (n = 19) of 2015. The concentrations of metals (As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Se, Sr, and Zn) were analyzed in blood serum samples of fishes by inductively coupled plasma optical emission spectrometry (ICP-OES), and Hg was determined by cold-vapor atomic absorption spectroscopy (CV-AAS). The general scheme of descending concentrations of metals in blood serum samples was as follows: Zn > Fe > Cu > Sr > Cr > Ni > Mn > Pb > Se > As > Cd > Hg. Zn was the most accumulated element (4.42-119.64 mg/L) in both seasons. Overall, the trace element content was higher in spring season, except Hg, Ni, Se, and Sr. The seasonal effect was confirmed for Mn, Zn, Mg, Glu, AST, and Chol levels and for most oxidative status markers. The gender effect was confirmed for Sr, GPx, PC, Chol, and CK concentrations. Trace metals (especially Cd, Cr, Cu, Fe, Hg, Mn, Ni, Sr, Zn, As) significantly affected some blood serum chemistry parameters. The correlation analysis between oxidative status markers (ROS, TAC, MDA, SOD, GSH, UA, BHB, and Alb) and trace metal (Cd, Cu, Ni, Sr, Hg, Pb, Fe, Mn) content confirmed statistically significant interactions in both seasons. Obtained results indicate specific actions of trace metals.

Increased serum interleukin-37 (IL-37) levels correlate with oxidative stress parameters in Hashimoto's thyroiditis

PURPOSE

Interleukin-37 (IL-37), member of the IL-1 family, is a natural suppressor of immune and inflammatory responses. Increased serum IL-37 levels were observed in several autoimmune diseases, including Graves' disease. To our knowledge, no data on Hashimoto's thyroiditis (HT) are available in the literature.

METHODS

Aim of our study was to measure serum IL-37 levels and evaluate their relationship, if any, with oxidative stress markers in HT patients. We enrolled 45 euthyroid HT patients (5 M e 40 F, median age 40 years) and 50 age- and sex-matched healthy controls. None was under L-thyroxine therapy. Serum IL-37 levels were measured by ELISA. Specific serum tests, such as derived reactive oxygen metabolites (d-ROMs), and biological anti-oxidant potential (BAP) test were performed in all subjects to investigate the changes in oxidative balance, and advanced glycation end products (AGEs) were determined as a specific marker of oxidative stress.

RESULTS

IL-37 levels were significantly higher in HT than in controls (median 475 vs. 268 pg/ml, P = 0.018). In the same patients, serum oxidants (d-ROMs) were increased and anti-oxidants (BAP) decreased compared with controls (P = 0.011 and < 0.0001, respectively), clearly indicating an enhanced oxidative stress. In addition, AGEs levels were higher in HT patients than in controls (210 vs. 140 AU/g prot, P < 0.0001) and directly correlated with IL-37 levels (P = 0.048). At multivariate analysis, the main independent predictors that influenced IL-37 levels were both anti-thyroid antibodies (P = 0.026) and AGEs levels (P = 0.001).

CONCLUSIONS

IL-37 is up-regulated in HT and may exert a protective role by counteracting oxidative stress and inflammation.

Fucoidan⁻Fucoxanthin Ameliorated Cardiac Function via IRS1/GRB2/ SOS1, GSK3β/CREB Pathways and Metabolic Pathways in Senescent Mice

The effects of low molecular weight fucoidan (LMWF) in combination with high-stability fucoxanthin (HSFUCO) on cardiac function and the metabolic pathways of aging mice (Mus musculus) were investigated. We demonstrated that LMWF and HSFUCO could improve cardiac function in aging mice. Aging mice were treated with LMWF and HSFUCO, either on their own or in combination, on 28 consecutive days. Electrocardiography and whole-cell patch-clamp were used to measure QT interval and action potential duration (APD) of the subjects. Cardiac tissue morphology, reactive oxygen species, and Western blot were also applied. Ultra-high-performance liquid chromatography⁻quadrupole time-of-flight (UPLC-QTOF) mass spectrometry was used for investigating metabolic alterations. The use of LMWF and HSFUCO resulted in improvements in both ventricular rhythms (QT and APD). Treatment with fucoidan and fucoxanthin reduced the expression levels of SOS1 and GRB2 while increasing GSK3β, CREB and IRS1 proteins expression in the aging process. Three main metabolic pathways, namely the TCA cycle, glycolysis, and steroid hormone biosynthesis, were highly enriched in the pathway enrichment analysis. When taken together, the LMWF and HSFUCO treatment improved both the ventricular rhythm and the muscular function of aging subjects by interfering with the metabolism and gene function.

Protocol for a feasibility randomised controlled trial of targeted oxygen therapy in mechanically ventilated critically ill patients

INTRODUCTION

Oxygen is the most commonly administered drug to mechanically ventilated critically ill adults, yet little is known about the optimum oxygen saturation (SpO2) target for these patients; the current standard of care is an SpO2 of 96% or above. Small pilot studies have demonstrated that permissive hypoxaemia (aiming for a lower SpO2 than normal by using a lower fractional inspired oxygen concentration (FIO2)) can be achieved in the critically ill and appears to be safe. This approach has not been evaluated in a National Health Service setting. It is possible that permissive hypoxaemia may be beneficial to critically ill patients thus it requires robust evaluation.

METHODS AND ANALYSIS

Targeted OXygen therapY in Critical illness (TOXYC) is a feasibility randomised controlled trial (RCT) to evaluate whether recruiting patients to a study of permissive hypoxaemia is possible in the UK. It will also investigate biological mechanisms that may underlie the links between oxygenation and patient outcomes. Mechanically ventilated patients with respiratory failure will be recruited from critical care units at two sites and randomised (1:1 ratio) to an SpO2 target of either 88%-92% or ≥96% while intubated with an endotracheal tube. Clinical teams can adjust FIO2 and ventilator settings as they wish to achieve these targets. Clinical information will be collected before, during and after the intervention and blood samples taken to measure markers of systemic oxidative stress. The primary outcome of this study is feasibility, which will be assessed by recruitment rate, protocol adherence and withdrawal rates. Secondary outcomes will include a comparison of standard critical care outcome measures between the two intervention groups, and the measurement of biomarkers of systemic oxidative stress. The results will be used to calculate a sample size, likely number of sites and overall length of time required for a subsequent large multicentre RCT.

ETHICS AND DISSEMINATION

This study was approved by the London - Harrow Research Ethics Committee on 2 November 2017 (REC Reference 17/LO/1334) and received HRA approval on 13 November 2017. Results from this study will be disseminated in peer-reviewed journals, at medical and scientific meetings, in the NIHR Journals Library and patient information websites.

TRIAL REGISTRATION NUMBER

NCT03287466; Pre-results.

Multivitamin and Mineral Supplementation Containing Phytonutrients Scavenges Reactive Oxygen Species in Healthy Subjects: A Randomized, Double-Blinded, Placebo-Controlled Trial

Phytonutrients and vitamin and mineral supplementation have been reported to provide increased antioxidant capacity in humans; however, there is still controversy. In the current clinical trial, we examined the antioxidant and DNA protection capacity of a plant-based, multi-vitamin/mineral, and phytonutrient (PMP) supplementation in healthy adults who were habitually low in the consumption of fruits and vegetables. This study was an eight-week, double-blind, randomized, parallel-arm, and placebo-controlled trial. PMP supplementation for eight weeks reduced reactive oxygen species (ROS) and prevented DNA damage without altering endogenous antioxidant system. Plasma vitamins and phytonutrients were significantly correlated with ROS scavenging and DNA damage. In addition, gene expression analysis in PBMC showed subtle changes in superoxide metabolic processes. In this study, we showed that supplementation with a PMP significantly improved ROS scavenging activity and prevented DNA damage. However, additional research is still needed to further identify mechanisms of actions and the role of circulating phytonutrient metabolites.

Resveratrol Alleviates Rheumatoid Arthritis via Reducing ROS and Inflammation, Inhibiting MAPK Signaling Pathways, and Suppressing Angiogenesis

Rheumatoid arthritis (RA) is a systemic autoimmune disease primarily affecting joints and is featured by chronic synovial inflammation and angiogenesis. We employed a bovine type-II collagen (BIIC)-induced Sprague-Dawley rat arthritis model and an in vitro RA model based on interleukin (IL)-1β-stimulated rat synovial cells (RSC-364) to explore the preventive effect of resveratrol on RA and the underlying mechanisms. We found that resveratrol ameliorated BIIC-elicited synovitis and RA-related pathological hallmarks such as inflammatory cell infiltration and angiogenesis in the synovial tissue. Also, BIIC-stimulated rats displayed increased serum levels of proinflammatory cytokines and reactive oxygen species (ROS), as manifested by elevated serum malonaldehyde contents combined with reduced superoxide dismutase activity. It is noteworthy that resveratrol abolished BIIC-induced ROS and inflammation, confirming the antioxidative and anti-inflammatory actions of resveratrol in the context of RA. Furthermore, immunoblotting indicated that resveratrol downregulated the increase in the levels of hypoxia-inducible factor-1α (HIF-1α) and that of the activated phosphorylation of p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase in IL-1β-stimulated RSC-364 cells. Moreover, we observed that resveratrol-treated RSC-364 cells displayed both G₀/G₁ cell-cycle arrest and enhanced levels of apoptosis. Altogether, the present evidence established the preventive role of resveratrol in RA progression. Mechanistically, resveratrol inhibits MAPK signaling pathways, likely by reducing ROS accumulation, to suppress the inflammatory response and cell proliferation and to provoke cell apoptosis in the synovial tissue, along with mitigation of HIF-1α-mediated angiogenesis. Thus resveratrol appears to hold great potential for clinical translation as a novel RA therapeutic.

Molecular hydrogen reduces acute exercise-induced inflammatory and oxidative stress status

Physical exercise induces inflammatory and oxidative markers production in the skeletal muscle and this process is under the control of both endogenous and exogenous modulators. Recently, molecular hydrogen (H2) has been described as a therapeutic gas able to reduced oxidative stress in a number of conditions. However, nothing is known about its putative role in the inflammatory and oxidative status during a session of acute physical exercise in sedentary rats. Therefore, we tested the hypothesis that H2 attenuates both inflammation and oxidative stress induced by acute physical exercise. Rats ran at 80% of their maximum running velocity on a closed treadmill inhaling either the H2 gas (2% H2, 21% O2, balanced with N2) or the control gas (0% H2, 21% O2, balanced with N2) and were euthanized immediately or 3 h after exercise. We assessed plasma levels of inflammatory cytokines [tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-6] and oxidative markers [superoxide dismutase (SOD), thiobarbituric acid reactive species (TBARS) and nitrite/nitrate (NOx)]. In addition, we evaluated the phosphorylation status of intracellular signaling proteins [glycogen synthase kinase type 3 (GSK3α/β) and the cAMP responsive element binding protein (CREB)] that modulate several processes in the skeletal muscle during exercise, including changes in exercise-induced reactive oxygen species (ROS) production. As expected, physical exercise increased virtually all the analyzed parameters. In the running rats, H2 blunted exercise-induced plasma inflammatory cytokines (TNF-α and IL-6) surges. Regarding the oxidative stress markers, H2 caused further increases in exercise-induced SOD activity and attenuated the exercise-induced increases in TBARS 3 h after exercise. Moreover, GSK3α/β phosphorylation was not affected by exercise or H2 inhalation. Otherwise, exercise caused an increased CREB phosphorylation which was attenuated by H2. These data are consistent with the notion that H2 plays a key role in decreasing exercise-induced inflammation, oxidative stress, and cellular stress.

Effect of Organic Selenium Supplementation on Selenium Status, Oxidative Stress, and Antioxidant Status in Selenium-Adequate Dairy Cows During the Periparturient Period

The periparturient period represents a stressful time for dairy cows as they transition from late gestation to early lactation. Oxidation stress occurs during this period owing to the increased metabolic activity. Antioxidants supplementation slightly above the suggested requirements may be beneficial in relieving this kind of stress. The objective of this study was to determine whether supplementing selenium (Se) yeast to diets with adequate Se concentrations affects Se status, oxidative stress, and antioxidant status in dairy cows during the periparturient period. Twenty multiparous Holstein cows were randomly divided into two groups with ten replicates in each group. During the last 4 weeks before calving, cows were fed Se-yeast at 0 (control) or 0.3 mg Se/kg dry matter (Se-yeast supplementation), in addition to Na selenite at 0.3 mg Se/kg dry matter in their rations. The concentrations of Se, reactive oxygen species (ROS), hydrogen peroxide (H₂O₂), hydroxyl radical, malonaldehyde (MDA), α-tocopherol and glutathione (GSH), the activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase (CAT), and the total antioxidant capacity (T-AOC) in plasma or erythrocyte of dairy cows were measured at 21 and 7 days prepartum, and at 7 and 21 days postpartum. Cows fed Se-yeast supplement during the last 4 weeks of gestation had higher plasma Se and lower MDA concentrations at 7 days prepartum, and at 7 and 21 days postpartum, and had higher whole blood Se and lower plasma ROS and H₂O₂ concentrations at 7 and 21 days postpartum compared with control cows. Se-yeast supplementation increased plasma and erythrocyte GSH-Px activities and erythrocyte GSH concentration at 7 days postpartum as compared to Se-adequate control cows. Compared with control cows, the enhanced SOD and CAT activities, increased α-tocopherol and GSH concentrations, and improved T-AOC in plasma at 7 and 21 days postpartum in Se-yeast-supplemented cows were also observed in this study. The results indicate that feeding Se-adequate cows a Se-yeast supplement during late gestation increases plasma Se status, improves antioxidant function, and relieves effectively oxidative stress occurred in early lactation.

Resistin and Plasma-reactive Oxygen Metabolite Levels in Obese and Non-obese Individuals with Chronic Periodontitis in Response to Non-surgical Periodontal Therapy

AIM

To assess and compare the impact of non-surgical periodontal therapy on plasma reactive oxygen metabolites and resistin values in chronic periodontitis obese and non-obese patients.

MATERIALS AND METHODS

Total 200 subjects were included in the present study and were broadly divided into two study groups with 100 patients in each group as follows: group A: Obese patients with chronic periodontitis, group B: Non-obese, normal weight patients with chronic periodontitis. Various following periodontal parameter were calculated at the baseline time and two months after the non-surgical periodontal therapy. Plasma reactive oxygen metabolite (RM) and serum and GCF resistin levelswere evaluated. Assessment of all the results was done by Statistical Package for Social Sciences (SPSS) software.

RESULTS

Significant results were obtained while doing an inter-group comparison of clinical attachment levels between two study groups. Significant results were obtained while comparing the clinical attachment levels in both the study groups at different time intervals. Significant 9 reduction in the RM was seen in Group B subjects in comparison to Group A subjects 2 months after non-surgical periodontal therapy.

CONCLUSION

In patients with chronic periodontitis, obesity can be considered as an important factor in the alteration of resistin levels.

CLINICAL SIGNIFICANCE

Obese patients should be motivated for reducing weight so that periodontal therapy and other treatment modalities could be carried out more effectively.

Reduction of oxidative stress a key for enhanced postoperative recovery with fewer complications in esophageal surgery patients: Randomized control trial to investigate therapeutic impact of anesthesia management and usefulness of simple blood test for prediction of high-risk patients

BACKGROUND

Oxidative stress may be an integral determinant of surgical stress severity. We examined whether the preoperative level of derivatives of reactive oxygen metabolites (d-ROMs), an oxidative stress biomarker based on total hydroperoxides in circulating blood, is predictive of increased risk of delayed recovery and complications after surgery, as well as the effects of anesthesia management on postoperative recovery in light of oxidative stress.

METHODS

Patients (American Society of Anesthesiologists physical status I-II) scheduled for a radical esophagectomy (n = 186) were randomly selected to receive inhalational sevoflurane (n = 94) or intravenous propofol (n = 92) anesthesia. Preoperative blood d-ROMs level, as well as pre-and postoperative plasma ferric-reducing ability, were analyzed to assess oxidative stress, with white blood cell (WBC) count, C-reactive protein (CRP) level, incidence of severe postoperative complications, and postoperative recovery process within 30 days after surgery also examined in a double-blind fashion.

RESULTS

Postoperative normalization of WBC and CRP was extended in patients with elevated preoperative d-ROMs [WBC versus d-ROMs: correlation coefficient (r) = 0.58 P < .001; CRP versus d-ROMs: r = 0.46 P < .001]. Receiver operating characteristics analysis of d-ROMs in relation to incidence of severe postoperative complications revealed an optimum d-ROMs threshold value of 410 UCarr and that patients with ≥410 UCarr had a greater risk of complications as compared to those with lower values (odds ratio = 4.7). Plasma ferric-reducing ability was decreased by 61 ± 185 mmol·l (P < .001) after surgery, demonstrating development of surgery-related oxidative stress, the magnitude of which was positively correlated with preoperative d-ROMs level (r = 0.16, P = .043). A comparison of the 2 anesthesia management protocols showed that patients who received propofol, an antioxidant anesthetic, had no postoperative decrease in ferric-reducing ability, lower incidence of severe postoperative complications (7 of 92 versus 18 of 94, P = .030, odds ratio = 0.35), and faster uneventful recovery time (WBC normalization days 7.1 ± 5.2 versus 13.6 ± 10.2, P < .001) as compared to those who received sevoflurane.

CONCLUSIONS

Elevated preoperative blood d-ROMs predicts greater intraoperative oxidative stress and increased postoperative complications with prolonged recovery, thus is useful for identifying high-risk patients for delayed and complicated surgical recovery. Reduction of oxidative stress is vital for enhanced recovery, with control by antioxidants such as propofol a possible solution.

IMPLICATION OF RELATIONSHIP BETWEEN OXIDATIVE STRESS AND ANTIOXIDANT STATUS IN BLOOD SERUM

Aim of the study was to examine the relationship between oxidative stress and overtraining syndrome in athletes by evaluation in serum oxidative and antioxidant status. In 43 athletes with non-functional overreaching (NFO)/overtraining syndrome(OTS) and 40 athletes without NFO/OTS -control athletes (CA), diacron-reactive oxygen metabolites (d-ROMs) and biological antioxidant potential (BAP) in serum, as well as ratio of d-ROMs and BAP test measurements - marker of oxidative stress, were assessed. Baseline data collection performed in both groups of athletes - with NFO/OTS and CA, followed by data collection in athletes with NFO/OTS after 28 days of rest. In athletes suspicious for OTS all measurements were performed after 2 more months of rest. Results of the study showed higher baseline d-ROMs in NFO/OTS athletes than in athletes without NFO/OTS, whereas antioxidant potential in CA was significantly higher, than in NFO/OTS athletes, After 28 days of rest there was significant decrease in d-ROM values in both: athletes with NFO and with OTS, as well as normalization of antioxidant status in athletes with NFO. Total 3 month of rest showed improvement in the oxidative status of athletes with OTS, reaching normal values, though antioxidant status remained without significant improvement, showing subnormal BAP values and decreased BAP/d-ROM ratio. The results demonstrate increased oxidative stress in overtraining state, creating disbalance between d-ROM production and antioxidant capacity. Thus, prolonged imbalance between oxidant production and antioxidant protection via attenuation of antioxidant capacity can be a cause of overtraining in highly trained athletes. In this study most frequently NFO and OTS were seen in wrestling, which needs further investigation and regular medical monitoring.

Role of hydrotherapy in the amelioration of oxidant-antioxidant status in rheumatoid arthritis patients

AIM

Rheumatoid arthritis (RA) is an inflammatory autoimmune disease. Reactive oxygen species (ROS) are involved in the pathophysiology of RA. Moderate intensity exercises have been reported to have anti-oxidant and anti-inflammatory effects. The aim of this study was to evaluate the effect of hydrotherapy on oxidant-antioxidant status in RA patients.

METHODS

Forty RA patients and 30 age- and sex-matched healthy controls were included in this study. RA patients were subdivided into two groups: the first group (n = 20) received treatment with conventional RA drugs, while the second group (n = 20) received hydrotherapy along with the conventional drugs for a period of 12 weeks. Disease Activity Score of 28 joints (DAS-28), ROS level, protein oxidation, lipid peroxidation, DNA damage and the activities of antioxidant enzymes were evaluated before and after 12 weeks of treatment.

RESULTS

RA patients showed a significant change in the oxidative stress biomarkers (ROS, P < 0.01; ferric reducing antioxidant potential, P < 0.001; malondialdehyde, P < 0.01; protein carbonyl, P < 0.001; tail length, P < 0.05) and decrease in the activities of anti-oxidant enzymes (superoxide dismutase [SOD], P < 0.01; glutathione peroxidase [GPx], P < 0.001). Conventional drug treatment has not produced any significant change in these parameters. However, cotreatment of drugs with hydrotherapy has decreased protein, lipid and DNA oxidation by increasing the activities of antioxidant enzymes (SOD and GPx).

CONCLUSION

Our results indicate that hydrotherapy along with drugs has reduced the severity of disease (DAS-28) by ameliorating the oxidant-antioxidant status in RA patients. Thus, in addition to conventional drugs, RA patients should be advised to have hydrotherapy (moderate intensity exercise) in their treatment regimen.

Small molecule targeting the Rac1-NOX2 interaction prevents collagen-related peptide and thrombin-induced reactive oxygen species generation and platelet activation

Essentials Reactive oxygen species (ROS) generation by NOX2 plays a critical role in platelet activation. Rac1 regulation of NOX2 is important for ROS generation. Small molecule inhibitor of the Rac1-p67phox interaction prevents platelet activation. Pharmacologic targeting of Rac1-NOX2 axis can be a viable approach for antithrombotic therapy.

SUMMARY

Background Platelets from patients with X-linked chronic granulomatous disease or mice deficient in nicotinamide adenine dinucleotide (phosphate) (NAD(P)H) oxidase isoform NOX2 exhibit diminished reactive oxygen species (ROS) generation and platelet activation. Binding of Rac1 GTPase to p67phox plays a critical role in NOX2 activation by facilitating the assembly of the NOX2 enzyme complex. Objective We tested the hypothesis that Phox-I, a rationally designed small molecule inhibitor of Rac-p67phox interaction, may serve as an antithrombosis agent by suppressing ROS production and platelet activation. Results Collagen-related peptide (CRP) induced ROS generation in a time-dependent manner. Platelets from Rac1-/- mice or human platelets treated with NSC23766, a specific Rac inhibitor, produced significantly less ROS in response to CRP. Treatment of platelets with Phox-I inhibited diverse CRP-induced responses, including: (i) ROS generation; (ii) release of P-selectin; (iii) secretion of ATP; (iv) platelet aggregation; and (v) phosphorylation of Akt. Similarly, incubation of platelets with Phox-I inhibited thrombin-induced: (i) secretion of ATP; (ii) platelet aggregation; (iii) rise in cytosolic calcium; and (iv) phosphorylation of Akt. In mouse models, intraperitoneal administration of Phox-I inhibited: (i) collagen-induced platelet aggregation without affecting the tail bleeding time and (ii) in vivo platelet adhesion/accumulation at the laser injury sites on the saphenous vein without affecting the time for complete cessation of blood loss. Conclusions Small molecule targeting of the Rac1-p67phox interaction may present an antithrombosis regimen by preventing GPVI- and non-GPVI-mediated NOX2 activation, ROS generation and platelet function without affecting the bleeding time.

Identification of urate hydroperoxide in neutrophils: A novel pro-oxidant generated in inflammatory conditions

Uric acid is the final product of purine metabolism in humans and is considered to be quantitatively the main antioxidant in plasma. In vitro studies showed that the oxidation of uric acid by peroxidases, in presence of superoxide, generates urate free radical and urate hydroperoxide. Urate hydroperoxide is a strong oxidant and might be a relevant intermediate in inflammatory conditions. However, the identification of urate hydroperoxide in cells and biological samples has been a challenge due to its high reactivity. By using mass spectrometry, we undoubtedly demonstrated the formation of urate hydroperoxide and its corresponding alcohol, hydroxyisourate during the respiratory burst in peripheral blood neutrophils and in human leukemic cells differentiated in neutrophils (dHL-60). The respiratory burst was induced by phorbol myristate acetate (PMA) and greatly increased oxygen consumption and superoxide production. Both oxygen consumption and superoxide production were further augmented by incubation with uric acid. Conversely, uric acid significantly decreased the levels of HOCl, probably because of the competition with chloride by the catalysis of myeloperoxidase. In spite of the decrease in HOCl, the overall oxidative status, measured by GSH/GSSG ratio, was augmented in the presence of uric acid. In summary, the present results support the formation of urate hydroperoxide, a novel oxidant in neutrophils oxidative burst. Urate hydroperoxide is a strong oxidant and alters the redox balance toward a pro-oxidative environment. The production of urate hydroperoxide in inflammatory conditions could explain, at least in part, the harmful effect associated to uric acid.

Exercise during hemodialysis does not affect the phenotype or prothrombotic nature of microparticles but alters their proinflammatory function

Hemodialysis patients have dysfunctional immune systems, chronic inflammation and comorbidity-associated risks of cardiovascular disease (CVD) and infection. Microparticles are biologically active nanovesicles shed from activated endothelial cells, immune cells, and platelets; they are elevated in hemodialysis patients and are associated with chronic inflammation and predictive of CVD mortality in this group. Exercise is advocated in hemodialysis to improve cardiovascular health yet acute exercise induces an increase in circulating microparticles in healthy populations. Therefore, this study aimed to assess acute effect of intradialytic exercise (IDE) on microparticle number and phenotype, and their ability to induce endothelial cell reactive oxygen species (ROS) in vitro. Eleven patients were studied during a routine hemodialysis session and one where they exercised in a randomized cross-over design. Microparticle number increased during hemodialysis (2064-7071 microparticles/μL, P < 0.001) as did phosphatidylserine+ (P < 0.05), platelet-derived (P < 0.01) and percentage procoagulant neutrophil-derived microparticles (P < 0.05), but this was not affected by IDE. However, microparticles collected immediately and 60 min after IDE (but not later) induced greater ROS generation from cultured endothelial cells (P < 0.05), suggesting a transient proinflammatory event. In summary IDE does not further increase prothrombotic microparticle numbers that occurs during hemodialysis. However, given acute proinflammatory responses to exercise stimulate an adaptation toward a circulating anti-inflammatory environment, microparticle-induced transient increases of endothelial cell ROS in vitro with IDE may indicate the potential for a longer-term anti-inflammatory adaptive effect. These findings provide a crucial evidence base for future studies of microparticles responses to IDE in view of the exceptionally high risk of CVD in these patients.

Citrate dialysate does not induce oxidative stress or inflammation in vitro as compared to acetate dialysate

Increased acetataemia during haemodialysis sessions has been associated with a number of abnormalities, including increased oxidative stress, pro-inflammatory cytokines and nitric oxide synthesis. However, citric acid may play an alternative role to acetate as a dialysate stabiliser given that the effect of citrate on complement and leukocyte activation is different to that of acetate. The purpose of this study was to compare the inflammatory effect in immunocompetent blood cells of acetate dialysate and citrate dialysate.

MATERIAL AND METHODS

The effect of acetate and/or citrate was investigated in the whole blood of uraemic patients and in healthy in vitro samples. Four types of dialysate were tested: dialysate 1, acetate-free with 1mmol/L of citrate; dialysate 2, with 0.8mmol/L of citrate and 0.3mmol/L of acetate; dialysate 3, citrate-free with 3mmol/L of acetate; and dialysate 4, citrate-free with 4mmol/L of acetate. The cell types used were: human monocyte culture (THP-1); and peripheral blood mononuclear cells (PBMCs) from healthy subjects and uraemic patients on haemodialysis. ICAM-1 was determined and levels of reactive oxygen species and total microvesicles were quantified.

RESULTS

Unlike the citrate dialysates, the dialysates with acetate (dialysate 3 and dialysate 4) induced increased ICAM-1 expression density in THP-1 cells; an increase in ICAM-1 expression was observed in the immunocompetent cells of healthy subjects with acetate dialysate (dialysate 3 and dialysate 4) but not with citrate dialysate (dialysate 1 and dialysate 2). No significant ICAM-1 differences were found between the different dialysates in the cells of haemodialysed patients. Reactive oxygen species expression and the number of microvesicles increased significantly with acetate dialysate but not with citrate dialysate in the cells of both healthy subjects and haemodialysed patients.

CONCLUSIONS

At the concentrations in which it is generally used in clinical practice, acetate-based dialysate increases oxidative stress and the total number of microvesicles and may induce other pro-inflammatory stimuli typical of uraemic patients on haemodialysis. Citrate dialysates do not induce this activation, which could make them a suitable alternative in clinical practice.

A Muscarinic Antagonist Reduces Airway Inflammation and Bronchoconstriction Induced by Ambient Particulate Matter in a Mouse Model of Asthma

Ambient particulate matter (PM) can increase airway inflammation and induce bronchoconstriction in asthma. This study aimed to investigate the effect of tiotropium bromide, a long-acting muscarinic antagonist, on airway inflammation and bronchoconstriction induced by ambient PM in a mouse model of asthma. We compared the effect of tiotropium bromide to that of fluticasone propionate and formoterol fumarate. BALB/c mice were sensitized to ovalbumin (OVA) via the airways and then administered tiotropium bromide, fluticasone propionate, or formoterol fumarate. Mice were also sensitized to ambient PM via intranasal instillation. Differential leukocyte counts and the concentrations of interferon (IFN)-γ, interleukin (IL)-5, IL-6, IL-13, and keratinocyte-derived chemokine (KC/CXCL1) were measured in bronchoalveolar lavage fluid (BALF). Diacron-reactive oxygen metabolites (dROMs) were measured in the serum. Airway resistance and airway inflammation were evaluated in lung tissue 24 h after the OVA challenge. Ambient PM markedly increased neutrophilic airway inflammation in mice with OVA-induced asthma. Tiotropium bromide improved bronchoconstriction, and reduced neutrophil numbers, decreased the concentrations of IL-5, IL-6, IL-13, and KC/CXCL1 in BALF. However, tiotropium bromide did not decrease the levels of dROMs increased by ambient PM. Though eosinophilic airway inflammation was reduced with fluticasone propionate, neutrophilic airway inflammation was unaffected. Bronchoconstriction was improved with formoterol fumarate, but not with fluticasone propionate. In conclusion, tiotropium bromide reduced bronchoconstriction, subsequently leading to reduced neutrophilic airway inflammation induced by ambient PM.

Glutathione S-transferase genes and the risk of type 2 diabetes mellitus: Role of sexual dimorphism, gene-gene and gene-smoking interactions in disease susceptibility

BACKGROUND

Compromised defense against reactive oxygen species (ROS) is considered important in the pathogenesis of type 2 diabetes mellitus (T2DM); therefore, genes encoding antioxidant defense enzymes may contribute to disease susceptibility. This study investigated whether polymorphisms in genes encoding glutathione S-transferase M1 (GSTM1), T1 (GSTT1), and P1 (GSTP1) jointly contribute to the risk of T2DM.

METHODS

In all, 1120 unrelated Russian subjects (600 T2DM patients, 520 age- and sex-matched healthy subjects), were recruited to the study. Genotyping was performed by multiplex polymerase chain reaction (PCR; del/del polymorphisms of GSTM1 and GSTT1) and TaqMan-based PCR (polymorphisms I105V and A114V of GSTP1). Plasma ROS and glutathione levels in study subjects were analyzed by fluorometric and colorimetric assays, respectively.

RESULTS

Genotype del/del GSTT1 was significantly associated with the risk of T2DM (odds ratio [OR] 1.60, 95% confidence interval [CI] 1.17-2.21, P = 0.003). Gender-stratified analysis showed that the deletion genotypes of GSTM1 (OR 1.99, 95% CI 1.30-3.05; P = 0.0002, Q = 0.016) and GSTT1 (OR 2.23, 95% CI 1.22-4.09; P = 0.008, Q = 0.0216), as well as genotype 114A/V of GSTP1 (OR 2.85, 95% CI 1.44-5.62; P = 0.005, Q = 0.02) were associated with an increased risk of T2DM exclusively in males. Three genotype combinations (i.e. GSTM1+ × GSTT1+, GSTM1+ × GSTP1 114A/A and GSTT1+ × GSTP1 114A/A) showed significant associations with a decreased risk of T2DM in males.

CONCLUSIONS

This study demonstrates, for the first time, that genes encoding glutathione S-transferases jointly contribute to the risk of T2DM, and that their effects on disease susceptibility are gender specific.