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1.
Redox Imbalance in CD4+ T Cells of Relapsing-Remitting Multiple Sclerosis Patients.
Tavassolifar, MJ, Moghadasi, AN, Esmaeili, B, Sadatpour, O, Vodjgani, M, Izad, M
Oxidative medicine and cellular longevity. 2020;:8860813
Abstract
As a prevalent autoimmune disease of the central nervous system in young adults, multiple sclerosis (MS) is mediated by T cells, particularly CD4+ subsets. Given the evidence that the perturbation in reactive oxygen species (ROS) production has a pivotal role in the onset and progression of MS, its regulation through the antioxidant molecules is too important. Here, we investigated the level of the redox system components in lymphocytes and CD4+ T cells of MS patients. The study was performed on relapsing-remitting MS (RRMS) patients (n = 29) and age- and sex-matched healthy controls (n = 15). Peripheral blood mononuclear cells (PBMCs) were cultured and stimulated by anti-CD3/CD28. The level of ROS, anion superoxide (O2 -), and L-š¯›¾-glutamyl-Lcysteinylglycine (GSH) was measured by flow cytometry in lymphocytes/CD4+ T cells. The gene expression level of gp91phox, catalase, superoxide dismutase 1/2 (SOD), and nuclear factor-E2-related factor (Nrf2) was also measured by real-time PCR. We found that lymphocytes/CD4+ T cells of RRMS patients at the relapse phase significantly produced higher levels of ROS and O2 - compared to patients at the remission phase (P value < 0.001) and healthy controls (P value < 0.001 and P value < 0.05, respectively). Interestingly, the gene expression level of gp91phox, known as the catalytic subunit of the NADPH oxidase, significantly increased in MS patients at the relapse phase (P value < 0.05). Furthermore, the catalase expression augmented in patients at the acute phase (P value < 0.05), while an increased expression of SOD1 and Nrf2 was found in RRMS patients at relapse and remission phases (P value < 0.05). The increased production of ROS in CD4+ T cells of RRMS patients highlights the importance of amplifying antioxidant components as an efficient approach to ameliorate disease activity in MS patients.
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2.
Electrophilic aldehydes generated by sperm metabolism activate mitochondrial reactive oxygen species generation and apoptosis by targeting succinate dehydrogenase.
Aitken, RJ, Whiting, S, De Iuliis, GN, McClymont, S, Mitchell, LA, Baker, MA
The Journal of biological chemistry. 2012;(39):33048-60
Abstract
Oxidative stress is a major cause of defective sperm function in cases of male infertility. Such stress is known to be associated with high levels of superoxide production by the sperm mitochondria; however, the causes of this aberrant activity are unknown. Here we show that electrophilic aldehydes such as 4-hydroxynonenal (4HNE) and acrolein, generated as a result of lipid peroxidation, target the mitochondria of human spermatozoa and stimulate mitochondrial superoxide generation in a dose- and time-dependent manner. The activation of mitochondrial electron leakage by 4HNE is shown to involve the disruption of succinate dehydrogenase activity and subsequent activation of an intrinsic apoptotic cascade beginning with a loss of mitochondrial membrane potential and terminating in oxidative DNA adduct formation, DNA strand breakage, and cell death. A tight correlation between spontaneous mitochondrial superoxide generation and 4HNE content (R(2) = 0.89) in untreated populations of human spermatozoa emphasized the pathophysiological significance of these findings. The latter also provide a biochemical explanation for the self-perpetuating nature of oxidative stress in the male germ line, with the products of lipid peroxidation stimulating free radical generation by the sperm mitochondria in a positive feedback loop.
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3.
Efficacy and safety of oxum in treatment of the venous ulcer.
Dharap, SB, Ghag, GS, Kulkarni, KP, Venkatesh, V
Journal of the Indian Medical Association. 2008;(5):326, 328-30
Abstract
The present study was carried out to find out the efficacy and safety of oxum in the treatment of venous ulcers. The oxum (superoxidised water) is a pH neutral, non-irritating, aqueous solution that possesses a good antiseptic, antimicrobial activity and wound healing properties. The study was conducted in 30 patients of venous ulcers with a culture examination positive for pathogenic microbial flora. All patients received a gauze dressing impregnated with oxum followed by compression bandage for 28 days. The primary endpoint was the calculation of ulcer size using ulcer tracing. Assessment of periwound oedema, periwound erythema, wound fibrin and wound granulations were considered as secondary endpoints. There was a singificant reduction in ulcer size starting from day 7 of the treatment. Significant improvements in secondary endpoints were observed. This study has demonstrated that oxum improved the clinical status, reduced the signs of inflammation in venous ulcers in addition to its well confirmed anti-infective properties.
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4.
Perioperative treatment with human growth hormone down-regulates apoptosis and increases superoxide production in PMN from patients undergoing infrarenal abdominal aortic aneurysm repair.
Decker, D, Springer, W, Tolba, R, Lauschke, H, Hirner, A, von Ruecker, A
Growth hormone & IGF research : official journal of the Growth Hormone Research Society and the International IGF Research Society. 2005;(3):193-9
Abstract
BACKGROUND Recombinant human growth hormone (hGH) therapy has a beneficial effect on catabolism and wound healing after major surgery. Polymorphonuclear neutrophils (PMN) play an important role in this context. In a prospective, double-blind, randomized, placebo-controlled trial we studied the effect of perioperative hGH treatment on postoperative wound healing and on changes in superoxide generation and susceptibility to apoptosis of PMN in elderly patients undergoing elective abdominal aortic aneurysm repair. METHODS Seven patients were treated with high-dose hGH (16 U/d) for nine days, seven patients with a placebo. IGF-I, neutrophil count, O2-production induced by opsonized zymosan and apoptosis of PMN were measured and correlated with clinical outcome. RESULTS Perioperative hGH treatment more than doubled the O2- production in PMN before and 24 h after surgery (p < 0.01). The long-term capacity of PMN to generate O2 in vitro was prolonged (p < 0.001) in the hGH group. Spontaneous and Fas-inducible apoptosis was strongly down-regulated in PMN after surgery in all patients (p < 0.01). hGH-treatment distinctly reduced apoptosis in PMN before and after surgery (p < 0.01). Clinical outcome was similar in both groups. CONCLUSION Perioperative hGH treatment results in an enhanced O2- production in PMN and in a prolongation of the functional life span of these cells. This may improve immune function and help to overcome the postoperative anergic state of the immune system especially in elderly individuals.
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5.
Phase I study of gemcitabine given weekly as a short infusion for non-small cell lung cancer: results and possible immune system-related mechanisms.
Levitt, ML, Kassem, B, Gooding, WE, Miketic, LM, Landreneau, RJ, Ferson, PF, Keenan, R, Yousem, SA, Lindberg, CA, Trenn, MR, et al
Lung cancer (Amsterdam, Netherlands). 2004;(3):335-44
Abstract
PURPOSE To define the maximum tolerated dose (MTD) and the nature of the toxicities associated with gemcitabine given as a short infusion to patients with non-small cell lung cancer (NSCLC). Secondary objectives were to monitor immunologic response, clinical response, and survival. PATIENTS AND METHODS Thirty-two patients diagnosed with advanced inoperable NSCLC and performance status of 0 or 1 participated in this study. Patients consisted of 22 males and 10 females whose median age was 62 years (range 32-79). Gemcitabine was administered as a 30 min infusion once weekly for 3 weeks followed by 1 week of rest. Patients were enrolled at six gemcitabine dose levels ranging from 1000 to 3500 mg/m2. Patients completed a median of four cycles (range 1-17). Responses were evaluated after every two cycles. RESULTS Toxicity was evaluated in all 32 patients. The MTD was not reached as gemcitabine was well tolerated at all dose levels. Grade 4 toxicity occurred in three (9%) patients: pulmonary and lymphocytopenia in one patient each, and both neurocortical and cardiac in one patient. Grade 3 toxicity was found in a total of 20 (63%) patients: pulmonary in 10 (31%) patients; pain in 6 (19%) patients; liver toxicity in 6 (19%) patients; leukopenia and lymphocytopenia in 5 (16%) patients each; anemia, nausea, and cardiac toxicity in 3 (9%) patients each; proteinuria and infection in 2 (6%) patients each; and hemorrhage in 1 (3%) patient. Of the 29 patients evaluable for response, seven objective responses were achieved: six at the 2200 mg/m2 dose level and one at the 2800 mg/m2 dose level. The distribution of responses differed significantly by dose (P = 0.0124 by the exact chi-square test for independence). The overall response rate was 24.1% (95% CI, 10.3-43.5%). At 6 h post-infusion, there was a significant increase in spontaneous tumor necrosis factor (TNF) release and stimulated interleukin (IL)-2 production, and significant decreases in total white blood cell and lymphocyte counts (CD3+, CD8+, and CD16+ lymphocytes) and resting and stimulated superoxide production by formyl-methionyl-leucyl-phenylalanine (fMLP), phorbol myristate acetate, and opsonized zymosan (OPS-Z). At 24 h post-infusion, there were significant decreases in total lymphocyte count, lymphocyte subsets (CD3+, CD4-, CD8+, CD56+, CD19+), and in resting and stimulated superoxide production by fMLP and OPS-Z. There also appeared to be an association between the levels of spontaneous TNF release and the severity of both gastrointestinal (GI) and pulmonary toxicities. CONCLUSION Gemcitabine given as a short infusion was well tolerated at the dose levels of 1000-3500 mg/m2. The MTD was not reached. Toxicities appeared to be cumulative with multiple cycles. Gemcitabine appears to have activity against NSCLC. Although there was a differential dose-response rate among dose levels, increasing the gemcitabine dose beyond 2200mg/m2 did not show increased clinical response. Gemcitabine appears to modulate the immune response, which may in turn mediate both response and toxicity, although no statistically significant correlation between immune and clinical response was detected.
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6.
Enhanced platelet release of superoxide anion in systemic hypertension: role of AT1 receptors.
GermanĆ², G, Sanguigni, V, Pignatelli, P, Caccese, D, Lenti, L, Ragazzo, M, Lauro, R, Violi, F
Journal of hypertension. 2004;(6):1151-6
Abstract
BACKGROUND Enhanced oxidative stress has been observed in hypertension, but the underlying mechanism has not been fully clarified. OBJECTIVE To study the relationship between oxygen free radicals and hypertension, using platelets as a tool to measure the cellular production of superoxide anion (O2). DESIGN Forty patients with hypertension were allocated randomly to groups to receive either irbesartan, an inhibitor of angiotensin II type 1 (AT1) receptors (n = 20), or a diuretic (hydrochlorothiazide) (n = 20). In each patient, collagen-induced production of O2 by platelets was studied before and after 4 weeks of treatment. Forty sex- and age-matched healthy individuals were studied as controls. METHODS Platelet-produced O2 was measured using lucigenin chemiluminescence and hydroethidine cytofluorimetric analysis. RESULTS Compared with healthy individuals, patients with hypertension showed a greater production of O2 by platelets (P < 0.001); there was no correlation between blood pressure and platelet O2 production. After treatment, no changes in platelet O2 formation were observed in patients receiving hydrochlorothiazide; conversely, those treated with irbesartan showed a significant (P < 0.001) decrease in platelet O2 production. At the end of the treatment, no differences in blood pressures were observed between the two groups. In-vitro incubation of platelets with angiotensin II elicited a significant increase in O2 (P < 0.001) that was dose-dependently inhibited by irbesartan and diphenylene iodonium, an inhibitor of NADPH oxidase. CONCLUSION Patients with hypertension showed an enhanced formation of O2 in platelets that was not dependent on blood pressure but could be mediated by AT1 receptors via NADPH oxidase activation.
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7.
Glucocorticoid excess induces superoxide production in vascular endothelial cells and elicits vascular endothelial dysfunction.
Iuchi, T, Akaike, M, Mitsui, T, Ohshima, Y, Shintani, Y, Azuma, H, Matsumoto, T
Circulation research. 2003;(1):81-7
Abstract
Glucocorticoid (GC) excess often elicits serious adverse effects on the vascular system, such as hypertension and atherosclerosis, and effective prophylaxis for these complications is limited. We sought to reveal the mechanism underlying GC-induced vascular complications. Responses in forearm blood flow to reactive hyperemia in 20 GC-treated patients were significantly decreased to 43+/-8.9% (mean+/-SEM) from the values obtained before GC therapy (130+/-14%). An administration of vitamin C almost normalized blood flow responses. In human umbilical vein endothelial cells (HUVECs), production of hydrogen peroxide was increased up to 166.5+/-3.3% of control values by 10(-7) mol/L dexamethasone (DEX) treatment (P<0.01). Concomitant with DEX-induced hydrogen peroxide production, intracellular amounts of peroxynitrite significantly increased and those of nitric oxide (NO) decreased, respectively (P<0.01). Immunoblotting analysis using anti-nitrotyrosine antibody showed that peroxynitrite formation was increased in DEX-treated HUVECs. Using inhibitors against metabolic pathways for generation of reactive oxygen species (ROS), we identified that the major production sources of ROS by DEX treatment were mitochondrial electron transport chain, NAD(P)H oxidase, and xanthine oxidase. These findings suggest that GC excess causes overproduction of ROS and thereby perturbs NO availability in the vascular endothelium, leading to vascular complications in patients with GC excess.
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8.
Effects of GH on lipid peroxidation and neutrophil superoxide anion-generating capacity in hypopituitary adults with GH deficiency.
Smith, JC, Lang, D, McEneny, J, Evans, LM, Scanlon, MF, Young, I, Davies, J
Clinical endocrinology. 2002;(4):449-55
Abstract
OBJECTIVES Untreated growth hormone deficiency (GHD) is implicated in the increased cardiovascular risk associated with adult hypopituitarism. Oxidative stress, predisposing to lipid peroxidation, may be an important mediator of endothelial dysfunction, a pro-atherogenic state associated with adult GHD. DESIGN AND PATIENTS In a randomized, double-blind, placebo-controlled study we investigated the effects of GH replacement on low-density lipoprotein (LDL) oxidation and neutrophil superoxide (O(-)(2)) generating capacity in 32 GHD adults (19 males, 13 females; age range 19-64 years) over 3 months. Thirty age- and sex-matched healthy controls were also studied. MEASUREMENTS Lipid hydroperoxides (HPOs) in plasma were measured using the ferrous oxidation with xylenol orange (FOX) assay. The susceptibility of LDL to oxidation was assessed by the copper-catalysed lag phase of LDL oxidation. Neutrophil O(-)(2)- generating capacity was assessed by a lucigenin-based chemiluminescent assay of NADPH oxidase activity. Body composition was assessed using bioelectrical impedance analysis. RESULTS Compared to controls, GHD subjects had higher LDL cholesterol (4.0 +/- 0.8 vs. 3.5 +/- 0.9 mmol/l, P < 0.01) and higher triglyceride concentrations (2.3 +/- 1.5 vs. 1.1 +/- 0.7 mmol/l, P < 0.001) but lower HDL cholesterol (1.1 +/- 0.3 mmol/l vs. 1.4 +/- 0.4 mmol/l, P < 0.01), lower levels of HPOs (0.72 +/- 0.35 vs. 0.92 +/- 0.20 microm, P < 0.01) and lower basal (2.5 +/- 1.5 vs. 4.5 +/- 2.3 mV/5 x 10(5) neutrophils, P < 0.01) and peak post-activation levels (23.2 +/- 11.1 vs. 34.4 +/- 15.6 mV/5 x 10(5) neutrophils, P < 0.01) of neutrophil O(-)(2)- generation. GH replacement resulted in an increase in HPOs from 0.70 +/- 0.39 to 0.86 +/- 0.19 microm (P < 0.05), although there was no change in the lag time of LDL oxidation. Neutrophil O(-)(2)- generating capacity was enhanced with a rise in basal O(-)(2)- generation from 2.8 +/- 1.4 to 5.4 +/- 4.6 mV/5 x 10(5) neutrophils (P < 0.05) and in peak post-activation O(-)(2)- generation from 21.9 +/- 9.5 to 35.8 +/- 21.7 mV/5 x 10(5) neutrophils (P < 0.05). LDL cholesterol was reduced from 4.1 +/- 0.8 mmol/l to 3.5 +/- 0.8 mmol/l (P < 0.01). No significant changes in measured parameters occurred in the placebo group. CONCLUSIONS Adult GHD is associated with reduced lipid peroxidation and impaired neutrophil O(-)(2)- generating capacity, both of which are reversible with GH replacement. Our data suggest that: (i) that oxidative stress is not a major feature of the pro-atherogenic state in hypopituitary adults with GHD and (ii) a role for GH in modulating neutrophil function and leucocyte-lipoprotein interactions.
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9.
Inspired superoxide anions attenuate blood lactate concentrations in postoperative patients.
Iwama, H, Ohmizo, H, Furuta, S, Ohmori, S, Watanabe, K, Kaneko, T, Tsutsumi, K
Critical care medicine. 2002;(6):1246-9
Abstract
OBJECTIVE Low concentrations of superoxide (O(2)(-)) constitute a portion of atmosphere negative ions in the form of O(2)-(H(2)O)(n), which has been reported to have a stimulatory effect on superoxide dismutase activity. If superoxide dismutase is activated by inspired negative ions containing O(2)(-), aerobic metabolism could be improved. To test this hypothesis, we examined blood lactate concentrations in postoperative patients with or without inhalation of air from a home humidifier that generates O(2)-(H(2)O)(n). DESIGN Prospective, randomized, controlled trial. SETTING Neurosurgical intensive care unit of a general hospital. PATIENTS Twenty postneurosurgical patients with arterial blood lactate concentrations >1.5 mmol/L were studied and were divided randomly into two groups. INTERVENTIONS One group received 40 L/min 40% oxygen flow from a home humidifier as an oxygen therapy for 4 hrs, followed by almost the same flow from a jet nebulizer, which generates positive ions, for 4 hrs. The other group received the reverse combination. MEASUREMENTS AND MAIN RESULTS During the 8-hr study, arterial blood lactate concentrations were measured every hour. There was a significant difference in the time course of blood lactate concentrations between the groups. In the group in which negative ions were first initiated for 4 hrs and positive ions thereafter, the lactate concentration decreased slightly at 3, 4, and 5 hrs and returned to the baseline concentration thereafter. In the group with the reverse combination, the lactate concentration did not change during the first 4 hrs but decreased thereafter after inhalation of negative ions. CONCLUSIONS Inspired O(2)(-) attenuates blood lactate concentrations. This may be attributed, in part, to the systemic stimulatory effect on superoxide dismutase activity, which accelerates oxidative phosphorylation in the mitochondria, thus attenuating lactate generation.
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10.
Adjuvant treatment of patients with antineutrophil cytoplasmic antibody-associated vasculitis with vitamins E and C reduces superoxide production by neutrophils.
Harper, L, Nuttall, SL, Martin, U, Savage, CO
Rheumatology (Oxford, England). 2002;(3):274-8
Abstract
OBJECTIVES Neutrophils when activated generate a respiratory burst which has been implicated in the pathogenesis of primary systemic vasculitis. Neutrophils from patients with vasculitis have a greater respiratory burst than normal healthy donors. The aim of this study was to assess the effects of antioxidant treatment (vitamins E and C) on the generation of a respiratory burst from neutrophils isolated from patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis. METHODS Neutrophils were isolated from patients with systemic vasculitis and healthy donors. Spontaneous superoxide generation was measured by the reduction of ferricytochrome c. The patients were treated with antioxidants, vitamins E and C, and spontaneous superoxide generation, vitamin C and total antioxidant capacity were measured before and after treatment. RESULTS The treatment of the patients with antioxidants resulted in a reduction in spontaneous superoxide generation (pre-treatment 8.41+/-0.7 nmol/10(6) cells; post-treatment 5.64+/-0.6 nmol/10(6) cells; P<0.05). There was no significant difference in the superoxide generation from normal controls who did not receive treatment, measured prior to commencement of the study and 10 days later (first reading 4.81+/-0.5 nmol/10(6) cells; second reading 5.32+/-0.4 nmol/10(6) cells; P>0.05). Total antioxidant capacity increased significantly following treatment with vitamins C and E (555.4+/-142 vs. 668.6+/-186 micromol/l trolox equivalent; P=0.01) as did vitamin C concentrations (56.5+/-27 vs. 137.7+/-64 micromol/l; P=0.002). CONCLUSIONS In this preliminary study, the treatment of patients with antioxidants, vitamins E and C, reduced neutrophil generation of superoxide and suggests that antioxidants may have an important role as adjuvant therapy. The evidence presented should form the basis of a larger randomized placebo-controlled trial of vitamins E and C as adjuvant therapy in patients with ANCA-associated systemic vasculitis.