Serum copper and erythrocyte superoxide dismutase in rheumatoid arthritis

Zerumbone Protects Rats from Collagen-Induced Arthritis by Inhibiting Oxidative Outbursts and Inflammatory Cytokine Levels

Rheumatoid arthritis (RA) is an immunocompromised disorder characterized by a marked increase in the synthesis of inflammatory molecules that stimulates the destruction of bones and cartilage. The conventional treatment modalities for RA are associated with adverse side effects and lack sensitivity, suggesting an immediate demand for alternate beneficial therapeutic remedies. The current study sought to understand more about zerumbone's anti-inflammatory properties in diagnosing collagen-induced arthritis (CIA) in experimental animals. The current study observed that zerumbone reduced clinical severity in CIA-induced animals compared to healthy animals. Zerumbone administration significantly decreased (p < 0.001) the concentration of SOD, CAT, GR, and GSH in treatment groups. Zerumbone administration drove down significantly (p < 0.001) the concentration of inflammatory cytokine molecules. Zerumbone was effective in bringing significant changes in levels of MPO, NO, LDH, MMP-8, and ELA. The therapeutic potential of zerumbone was found to be associated with reduced joint destruction and restored normal histology in the cartilage and tissue. Adsorption, distribution, metabolism, excretion, and toxicity studies were used to determine the druglike properties of zerumbone. ProTox-II studies revealed that zerumbone did not possess toxic properties like hepatotoxicity, immunotoxicity, carcinogenicity, mutagenicity, and cytotoxicity. Therefore, the present study evaluated the therapeutic properties of zerumbone in CIA animal models.

Common trace metals in rheumatoid arthritis: A systematic review and meta-analysis

INTRODUCTION

Environmental risk factors regrading rheumatoid arthritis (RA) have not been explored extensively. Selenium (Se), zinc (Zn) and copper (Cu) nutrients were reported to associate with RA, but the results were inconsistent. Therefore, we conduct present study to meta-analyze the relationship between serum Se, Zn and Cu and RA and review the potential mechanisms.

METHODS

PubMed, Web of Science and Cochrane Library were comprehensively searched till October 1, 2018 for pertinent studies. Standard mean differences (SMDs) and 95% confident intervals (CIs) were calculated according to random effects model.

RESULTS

Finally 41 literatures were included. Meta-analysis of 16 studies involving 806 RA patients and 959 health controls showed that serum Se (SMD = -1.04, 95% CI = -1.58 to -0.50) was decreased in RA patients, and 23 literatures with 1398 patients and 1299 controls reported serum Zn (SMD = -1.20, 95% CI = -1.74 to -0.67) was decreased. But serum Cu (SMD = 1.26, 95% CI = 0.63 to -1.89) was increased with 26 studies including 1723 patients and 1451 controls. Meta-regression reported that steroid use was positively related to serum level of Se in RA (β = 0.041, 95% CI = 0.002 to 0.079). Differences in serum Se, Zn and Cu between rheumatoid arthritis patients and controls were all related with the geographical distribution.

CONCLUSIONS

Patients with RA have significant decreased serum Se and Zn and increased serum Cu than health controls, suggesting potential roles of Se, Zn and Cu in the pathogenesis of RA. Patients and rheumatologist should give enough attention to the monitor of these elements during follow up.

Zinc Status and Autoimmunity: A Systematic Review and Meta-Analysis

Zinc is an essential trace element for living organisms and their biological processes. Zinc plays a key role in more than 300 enzymes and it is involved in cell communication, proliferation, differentiation and survival. Zinc plays also a role in regulating the immune system with implications in pathologies where zinc deficiency and inflammation are observed. In order to examine the experimental evidence reported in the literature regarding zinc levels in the body of patients with autoimmune disorders compared to control individuals, a systematic review and meta-analysis were performed. From 26,095 articles identified by literature search, only 179 of them were considered potentially relevant for our study and then examined. Of the 179 articles, only 62 satisfied the inclusion criteria. Particularly for Fixed Model, Zn concentration in both serum (mean effect = −1.19; confidence interval: −1.26 to −1.11) and plasma (mean effect = −3.97; confidence interval: −4.08 to −3.87) samples of autoimmune disease patients was significantly lower than in controls. The data presented in our work, although very heterogeneous in the manner of collecting and investigating samples, have proved to be extremely consistent in witnessing a deficiency of zinc in serum and plasma of patients compared to controls.

Serum Levels of Copper and Zinc in Patients with Rheumatoid Arthritis: a Meta-analysis

Many publications with conflicting results have evaluated serum levels of copper (Cu) and zinc (Zn) in patients with rheumatoid arthritis (RA). To derive a more precise estimation of the relationship, a meta-analysis was conducted. Relevant published data were retrieved through PubMed, Chinese National Knowledge Infrastructure (CNKI), and Chinese Biomedical Database (CBM) before September 20, 2014. Weighted mean difference (WMD) with a 95 % confidence interval (95 % CI) was calculated using STATA 11.0. A total of 26 studies, including 1444 RA cases and 1241 healthy controls, were collected in this meta-analysis. Pooled analysis found that patients with RA had a higher serum level of Cu and a lower serum Zn level than the healthy controls (Cu (μg/dl), WMD = 31.824, 95 % CI = 20.334, 43.314; Zn (μg/dl), WMD = -12.683, 95 % CI = -19.783, -5.584). Subgroup analysis showed that ethnicity had influence on the serum level of Cu (μg/dl) (Caucasian, WMD = 43.907, 95 % CI = 35.090, 52.723, P < 0.001; Asian, WMD = 14.545, 95 % CI = -12.365, 41.455, P = 0.289) and Zn (μg/dl) (Caucasian, WMD = -11.038, 95 % CI = -23.420, 1.344, P = 0.081; Asian, WMD = -14.179, 95 % CI = -18.963, -9.394, P < 0.001) in RA and healthy controls. No evidence of publication bias was observed. This meta-analysis suggests that increased serum level of Cu and decreased serum level of Zn are generally present in RA patients.

Effects of Atenolol, Labetalol and Methyldopa on Endogenous Antioxidants In-vitro

The aim of this study was to investigate whether atenolol, labetalol and methyldopa, which are commonly used for the treatment of hypertension in pregnancy, can induce antioxidant activity.

Reactive oxygen species scavengers (plasma thiol, red cell lysate thiol, red cell superoxide dismutase, red cell membrane thiol and plasma glutathione) were measured after incubation of peripheral blood with atenolol and methyldopa, respectively.

The results showed that atenolol and labetalol could significantly raise the levels of plasma thiol and membrane thiol but had no effects on lysate thiol, superoxide dismutase and glutathione. The effects on membrane thiol occurred after 60 min incubation and on plasma thiol after 120 min incubation.

The data also suggest that atenolol and labetalol at lower concentrations tend to have additive effects on reactive oxygen species scavengers but at higher concentrations do not.

Methyldopa had no significant effect on any of the parameters measured.

These findings suggest that atenolol and labetalol are able to induce higher levels of antioxidant activity.

The effects of nitric oxide-oxidase and putative glutathione-peroxidase activities of ceruloplasmin on the viability of cardiomyocytes exposed to hydrogen peroxide

Ceruloplasmin (CP), a ferroxidase (EC 1.16.3.1) and a scavenger of reactive oxygen species, is an important extracellular antioxidant. Bovine CP indeed protects the isolated heart under ischemia-reperfusion conditions. Human CP has been shown to also exhibit, in vitro, glutathione (GSH)-peroxidase and nitric oxide (NO)-oxidase/S-nitrosating activities. This work tested, using bovine CP, the hypothesis that both activities could provide cytoprotection during oxidative stress induced by hydrogen peroxide (H(2)O(2)), the former activity by consuming H(2)O(2) and the latter by shielding thiols from irreversible oxidation. In acellular assays, bovine CP stimulated the generation of the nitrosating NO(+) species from the NO donors propylaminepropylamine-NONOate (PAPA/NO), S-nitroso-N-acetylpenicillamine, and S-nitrosoglutathione. This NO-oxidase activity S-nitrosated GSH as well as CP itself and was not affected by H(2)O(2). In contrast to human CP, bovine CP consumed H(2)O(2) in an additive rather than synergistic manner in the presence of GSH. A nonenzymatic scavenging of H(2)O(2) could have masked the GSH-peroxidase activity. Cytoprotection was evaluated using neonatal rat cardiomyocytes. CP and PAPA/NO were not protective against the H(2)O(2)-induced loss of viability. In contrast, GSH provided a slight protection that increased more than additively in the presence of CP. This increase was canceled by PAPA/NO. CP's putative GSH-peroxidase activity can thus provide cytoprotection but is possibly affected by the S-nitrosation of a catalytically important cysteine residue.

Effects of hyaluronan on nitric oxide levels and superoxide dismutase activities in synovial fluid in knee osteoarthritis

The aim of the present study was to evaluate the effects of hyaluronan (HA) on nitric oxide (NO) levels and superoxide dismutase (SOD) enzyme activities in synovial fluid (SF) in the treatment of patients with knee osteoarthritis (OA). SF samples were aspirated from OA patients before the commencement of the treatment (n=23) and 6 weeks after they were treated with HA products. NO levels and SOD activities were compared between the pre- and post-treatment of OA patients and of the control group (n=10). SF NO levels were significantly higher in patients with OA before the commencement of the treatment compared with the post-treatment (p<0.001) and the control groups. The SF SOD activity of patients before the commencement of the treatment was lower than the values in the controls and post-treatment (p<0.001). There is no significant correlation between SF NO and SOD levels and the radiographic changes of the OA knee according to Kellgren-Lawrence grading (p>0.05). Also, the Western Ontario and McMaster Universities Osteoarthritis index (WOMAC) pain scores and physical function scores were gradually improved. These findings made us think that SF NO was a potent mediator in cartilage damage in OA, whereas SOD was an antioxidant mediator in the same process. Exogenous HA injections might reduce the NO levels and increase SOD activities in synovial fluid. These effects also do not seem to be dependent on the radiographic grading of the OA knee. More comprehensive studies are needed to clarify a possible clinical significance of this topic, and we suggest that this is an important area for further research into new treatment options.

Plasma total antioxidant capacity, lipid peroxidation, and erythrocyte antioxidant enzyme activities in patients with rheumatoid arthritis and osteoarthritis

OBJECTIVES

The metabolism of cells in inflammatory and noninflammatory arthritic joint diseases is subject to complex environmental controls. The aim of the present study was to investigate the total antioxidant capacity (TAC), levels of lipid peroxidation (LPO), and antioxidant enzyme activities in patients with rheumatoid arthritis (RA) and osteoarthritis (OA).

DESIGN AND METHODS

Plasma levels of TAC, malondialdehyde (MDA), the activities of some erythrocyte antioxidant enzymes, as well as erythrocyte sedimentation rates (ESR) were estimated in patients with RA and OA and compared with controls.

RESULTS

The plasma TAC levels were significantly lower in the RA group than the OA and control group (P < 0.05). Plasma MDA concentrations were significantly higher in patients with RA than those with OA and healthy subjects (P < 0.05). Erythrocyte GSH-Px and CAT activities were found to be significantly lower in patients with RA than those with OA and healthy subjects (P < 0.05, P < 0.05, respectively). However, there were no significant differences in erythrocyte SOD activities between the groups (P > 0.05). ESR were significantly higher in RA patients than in healthy subjects and patients with OA (P < 0.01). Moreover, there were significant negative correlations between TAC vs. MDA, ESR vs. TAC, and a positive correlation between ESR vs. MDA in the RA group (r = -0.398, P < 0.05; r = -0.422, P < 0.05; r = 0.530, P < 0.05, respectively).

CONCLUSIONS

Our results demonstrated that levels of LPO are increased in patients with RA compared to patients with OA. In addition, plasma TAC levels are decreased in RA due to its inflammatory character. We conclude that detecting plasma TAC levels with this novel method may be used as a routine and rapid test to verify the levels of oxidative stress in RA. Furthermore, correlating TAC and LPO levels with acute phase reactants such as ESR may give some clues about disease activity in RA.

Immunochemical and enzymatic study of ceruloplasmin in rheumatoid arthritis

Forty adult patients (30 women and 10 men) with rheumatoid arthritis (RA), treated with nonsteroidal anti-inflammatory drugs, were studied. Serum levels of immunoreactive ceruloplasmin, oxidase activity of the ceruloplasmin and total copper, as well as the specific oxidase activity (enzyme activity per unit of mass) and the copper/immunoreactive ceruloplasmin relationship were significantly higher in the group of patients than in the healthy control group (p < 0.001). However, no significant difference was found for the concentration of non-ceruloplasmin copper between both groups. A statistically significant negative correlation was obtained for the concentration of serum thiobarbituric acid-reacting substances with the immunoreactive ceruloplasmin and its oxidase activity in the group of patients (p < 0.005). These results suggest that in RA increases of serum copper are produced at the expense of the fraction linked to the ceruloplasmin, diminishing the proportion of apoceruloplasmin and other forms poor in copper. Although the increase in the serum concentration of ceruloplasmin might offer an additional safeguard against oxidative stress. it does not appear to have a beneficial effect upon the activity of the illness as evaluated by means the biological inflammation markers C-reactive protein, erythrocyte sedimentation rate and sialic acid.

Antioxidants: their role in pregnancy and miscarriage

The aim of this study was to examine the role of antioxidants within the normal menstrual cycle, in healthy pregnancy, and in women suffering first-trimester miscarriage. The antioxidants chosen comprised of two from peripheral blood-plasma thiol and ceruloplasmin-and two extracellular parameters-superoxide dismustase (SOD) and red cell lysate thiol. We found that antioxidant levels varied little throughout the menstrual cycle. Pregnancies that went successfully to term were associated with increased levels of ceruloplasmin and SOD early in the first trimester. These changes were thought to offer the cell protection from the damage caused by the increased oxidative stress associated with pregnancy. First-trimester miscarriage was associated with significantly reduced levels of SOD. A subgroup of patients who miscarried in their first pregnancy, but whose second pregnancies were successful, had higher levels of plasma thiol and significantly reduced levels of red cell lysate thiol in the on-going pregnancy compared to levels at the time of miscarriage. Miscarriage and pregnancy appear to be associated with increased oxidative stress. In a successful pregnancy, however, changes occurred within the peripheral blood that offered protection from oxidant attack.

Trace element and magnesium levels and superoxide dismutase activity in rheumatoid arthritis

It has been suggested that reactive oxygen metabolites and trace elements play some role in the etiology and pathogenesis of rheumatoid arthritis (RA). Superoxide dismutase (SOD) is believed to exert an important protective role against oxygen toxicity. The aim of the study was to investigate the probable changes in the levels of trace elements and SOD activity in RA. Plasma and erythrocyte copper, zinc, and magnesium levels and erythrocyte SOD activity were measured in groups of controls and RA cases. Significantly increased erythrocyte SOD activity was found in RA patients in comparison with controls (p < 0.0001). A rise in erythrocyte Zn level (p < 0.0001) and plasma Cu level (p < 0.0001) and a decrease in erythrocyte Cu level (p < 0.05) and plasma Zn level (p < 0.05) were obtained in RA patients when compared to controls. Plasma and erythrocyte Mg levels of the RA patients showed slight and statistically insignificant reductions when compared to controls (p > 0.05). In RA patients, there were positive correlations between erythrocyte SOD activity and Mg level (r = 0.4345, p < 0.01) and between erythrocyte Zn level and plasma Cu level (r = 0.4132, p < 0.01). There were negative correlations between erythrocyte SOD activity and plasma Zn level (r = -0.3605, p < 0.05) and between plasma Zn level and erythrocyte Cu level (r = -0.4578, p < 0.01) in RA patients.

Carnitine and antioxidants levels in patients with rheumatoid arthritis

Rheumatoid arthritis (RA) is a heterogeneous disorder with a spectrum of clinical severity ranging from mild arthritis to a crippling joint disease with involvement of internal organs. Carnitine is essential for muscle energy production and is required for the transport of long chain fatty acids and the acyl coenzyme A derivatives across the inner mitochondrial membrane. The levels of malondialdehyde (MDA), an index of lipid peroxidation, and the antioxidants copper-zinc superoxide dismutase (CuZnSOD), glutathione (GSH), ceruloplasmin (CP), catalase (CAT), and carnitine were assessed in 42 patients with RA and 24 control subjects. While plasma carnitine and erythrocyte CuZnSOD levels were significantly lower in the patients with RA compared with the control group (p<0.01 and p<0.001, respectively), the CAT level was not different from controls (p>0.05). Plasma MDA, CP, and erythrocyte GSH levels were significantly higher than in the control group (p<0.001, p<0.001 and p<0.01, respectively). MDA levels showed a positive correlation with CP and GSH levels (r=0.716, p<0.001 and r=0.492, p<0.01, respectively). However, MDA, GSH, and CP demonstrated a negative correlation with carnitine (r=-0.719, p<0.001; r=-0.559, p<0.01, and r=-0.635, p<0.001, respectively) in the patient group but not in controls. There was also a significant positive correlation between CP and GSH levels (r=0.561, p<0.01). However, neither CuZnSOD nor CAT levels demonstrated correlation withcarnitine, MDA, GSH, or CP levels. It was interesting that CAT activity was not altered and CuZnSOD activity decreased when compared with the control group. These results suggest that while CP, MDA and GSH levels increased, carnitine and CuZnSOD levels decreased, but CAT activity was unchanged.

Evidence for carbimazole as an antioxidant?

There is evidence in the literature to support the view that antioxidants are involved in the pathogenesis of Graves disease and that antioxidants may act as free radical scavengers. This study has compared the effects of a 12 month course of conventional Carbimazole therapy on peripheral blood antioxidant levels with those of a 12 month course of a higher dose treatment regime. Fifty seven patients were enrolled into the study. Those in Group 1 (n = 23) received a 12 month course of 60 mg/day Carbimazole. Those in Group 2 (n = 34) received 45 mg/day for the first month, 30 mg/day for the second and 20 mg/day for the remaining 10 months of treatment. T3 was added in both groups after 2-4 months to maintain patients euthyroid. Baseline samples were also obtained from 30 control subjects. Blood samples were taken for the measurement of plasma thiol (PSH), lysate thiol (LSH), superoxide dismutase (SOD) and caeruloplasmin (CP) and for routine thyroid function tests (TT4, TT3 and TSH). In untreated Graves' patients, serum levels of PSH and SOD were reduced and levels of LSH increased compared to controls. Following 2 months high dose Carbimazole therapy there was a significant increase in PSH levels and a significant reduction in CP levels compared to presentation levels. In the more conventional dose Group 2 patients PSH levels also rose significantly during the first 2 months of treatment. Levels for both groups were still significantly lower than the control group. After 12 months high dose Carbimazole therapy PSH levels had decreased so that they no longer differed from untreated levels. LSH and SOD levels still remained abnormal. CP levels continued to fall. Similar findings were obtained in those patients receiving the more conventional course of treatment. At no point was their any significant difference in antioxidant levels between the two treatment groups. The abnormal levels of antioxidants in the serum of untreated Graves' patients confirm their involvement in the pathogenesis of Graves' disease. Carbimazole therapy appeared to have only short term effects on the peripheral blood levels of the antioxidants measured. Carbimazole appeared to act only on the extra cellular markers of antioxidant activity (PSH, CP) although the disease itself had marked intracellular effects (LSH, SOD). These findings suggest that Carbimazole does not act as a free radical scavenger.

Correlation between blood antioxidant levels and lipid peroxidation in rheumatoid arthritis

OBJECTIVES

To investigate the relationship between lipid peroxidation and certain antioxidant parameters in the blood of rheumatoid arthritis patients.

METHODS AND RESULTS

In the present study, significantly increased lipid peroxidation, measured as malondialdehyde (MDA), was demonstrated in the plasma of rheumatoid arthritis patients (p < 0.01). The activities of erythrocyte antioxidant enzymes, superoxide dismutase and catalase remained unaltered. However, erythrocyte glutathione and plasma ceruloplasmin levels were significantly higher in patients (p < 0.001). Moreover, a positive correlation was also observed between these two parameters and MDA levels in the patient group but not in controls. Interestingly, a significant positive correlation also existed between red cell glutathione and plasma ceruloplasmin levels.

CONCLUSION

These results suggest that increased oxidant stress present in rheumatoid arthritis may lead to compensatory changes in the levels of some antioxidants, viz. glutathione and ceruloplasmin. These changes, in turn, may provide additional protection against lipid peroxidation in rheumatoid arthritis.

Pharmacokinetics and pharmacodynamics in copper deficiency. I. Antiinflammatory activity of aspirin

The effect of nutritional copper (Cu) deficiency on the antiinflammatory activity and pharmacokinetics of aspirin (ASA) was investigated in rats. Male, weanling Sprague-Dawley rats were fed either a Cu-deficient (CuD) or Cu-sufficient (CuS) diet for 49-50 d. The antiinflammatory activity of ASA was studied using the carrageenan-induced paw edema (CPE) test. ANOVA analyses of edema volumes at 2, 3, 4, 5, and 21 h postcarrageenan indicated significant differences between groups. The percent inhibition of edema due to ASA treatment in CuS was lower than that in CuD rats at 5 h, AUC5h, and AUC21h. ASA was found to be significantly more effective in inhibiting the CPE in CuD rats when compared to the CuS rats. Thus, we hypothesized that the increase in ASA's antiinflammatory activity in CuD rats was a result of a decrement in its elimination during nutritional Cu deficiency. The elimination of ASA in CuD and CuS rats was studied using an iv dose of 200 mg/kg. Concentrations of ASA and salicylic acid (SA) were determined in blood; whereas the concentrations of SA, salicylic phenol-glucuronide (SPG), and salicyluric acid (SUA) were determined in urine by HPLC. The results of the pharmacokinetic analyses from blood and urinary data indicated no significant differences in the disposition of ASA between CuD and CuS rats. For instance, the total body clearance for ASA (mean +/- SD, mL/min/kg) was 37.9 +/- 9.4 and 38.5 +/- 13.9 (p > 0.05); and the volume of distribution (Vd) for ASA (mean +/- SD, mL/kg) was 385.5 +/- 110.3 and 397.1.1 +/- 137.9 (p > 0.05) for CuD and CuS groups, respectively. Thus, contrary to our hypothesis, the enhanced antiinflammatory activity of ASA in CuD rats does not appear to be mediated via a decrement in the elimination of the drug. In addition, plasma ASA-esterase activity was found to be independent of Cu nutritional status.

Prostacyclin, thromboxane and antioxidant levels in pregnancy-induced hypertension

1. Plasma 6-keto-prostaglandin F1 alpha (6-keto-PGF 1 alpha, a major metabolite of prostacyclin), plasma thromboxane B2 (TXB2, a major metabolite of thromboxane A2) and five antioxidants (indirect markers of reactive oxygen species) namely, plasma thiol, erythrocyte lysate thiol, erythrocyte superoxide dismutase, plasma total glutathione and erythrocyte membrane thiol, were measured in 25 healthy non-pregnant women, 36 normotensive pregnant women and 35 women with pregnancy-induced hypertension (PIH). 2. The levels of TXB2 were significantly increased in normal pregnant women and PIH women with or without proteinuria compared with non-pregnant women. The concentrations of TXB2 in PIH women with proteinuria were higher than those without proteinuria (P < 0.05). 3. The levels of 6-keto-PGF1 alpha in healthy non-pregnant women and PIH women with or without proteinuria were significantly lower than that in normotensive pregnant women (all of three P < 0.01). There were no significant differences between healthy non-pregnant women and PIH women with and without proteinuria. 4. The ratio of TXB2 to 6-keto-PGF1 alpha was markedly elevated in PIH women with or without proteinuria compared with normotensive pregnant women and healthy non-pregnant women. The difference between PIH women with proteinuria and those without proteinuria was not significant (P > 0.05). 5. The levels of plasma thiol, superoxide dismutase and glutathione were significantly decreased in PIH women compared with normotensive pregnant women. 6. There were significant positive correlations between the levels of prostaglandins and antioxidant activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Copper and zinc body levels in inflammation: an overview of the data obtained from animal and human studies

The development of acute and chronic inflammatory processes induces, in the laboratory animal, a net accumulation of both copper and zinc in many body compartments, the inflamed area included. In rheumatoid arthritis, as well as in animal models, only plasma zinc concentration seems to be significantly correlated with disease severity, while the increase in total plasma copper could be described as an "all or nothing" phenomenon. Moreover, in rheumatoid arthritis, it appears that the disease develops and progresses without being linked to either copper or zinc deficiency conditions. Thus, it seems reasonable to suggest that a rationale for the use of copper and/or zinc in the treatment of inflammatory disorders can only be drawn from the intrinsic pharmacological properties of such trace elements, rather than from the need for their repletion.

Effect of vitamin C administration in modulating some biochemical changes in arthritic rats

Two phases of arthritis, acute phase (four days after adjuvant inoculation) and chronic phase (21 or 29 days after adjuvant inoculation) were studied in male rats. The effect of administration of vitamin C in a daily oral dose of 50 mg/kg body wt for four and 21 days starting on the day of adjuvant inoculation and for 7 days starting 21 days after adjuvant inoculation against these phases of arthritis was demonstrated. Results showed that prolonged administration of vitamin C (21 days) increased the lowered serum sulphydryl (SH-groups) to prearthritic values while it decreased the elevated level of blood glutathione (GSH) of arthritic rats. However, neither (four-day) nor seven-day treatment with vitamin C exerted any significant changes in these parameters. The results showed also a slight significant increase in the level of erythrocyte superoxide dismutase activity (SOD) [1.15.1.1] upon seven-day treatment with vitamin C. Meanwhile, four-, 21- or seven-day treatment with vitamin C produced no significant change in the elevated levels of serum ceruloplasmin (Cp) and alpha 2-macroglobulin (alpha 2-M) of arthritic rats. However, 21-day and 7-day administration of vitamin C has improved the lowered A/G ratio in these animals. The improvement in these parameters after prolonged administration of vitamin C was explained in the light of the antioxidant property of this vitamin and suggests a beneficial role for it in the treatment of arthritis.

Antioxidant systems in normal pregnancy and in pregnancy-induced hypertension

Increased free radical activity has been implicated in the pathogenesis of pregnancy-induced hypertension. This article investigates whether changes in antioxidant systems contribute to this condition. Two extracellular (plasma thiols and ceruloplasmin) and two intracellular (red blood cell lysate thiols and red blood cell superoxide dismutase) antioxidant markers were assayed in 25 nonpregnant women, 16 pregnant women with normal blood pressure, 19 women with pregnancy-induced hypertension, and 13 women with proteinuric pregnancy-induced hypertension. In the normotensive pregnant group (in comparison with the nonpregnant group) the plasma thiol level was reduced (p less than 0.001) and the ceruloplasmin level raised (p less than 0.005), suggesting increased free radical activity. The lysate thiol level increased (p less than 0.005), which may reflect a compensatory protective response. In the hypertensive pregnant groups the lysate thiol rise was not present. These red blood cells may be more prone to oxidative stress. Whether this situation is a cause or an effect of oxidative stress in pregnancy-induced hypertension has yet to be elucidated.

Effects on leukocyte function by arthroplasty. Thromboplastin activity and oxygen-derived free radicals studied in rheumatoid arthritis and arthrosis

We examined thromboplastin activity (TA) of monocytes and release of oxygen-derived free radicals (ODRFs) from monocytes and granulocytes before and after implantation of a hip or a knee prosthesis in 7 patients with rheumatoid arthritis and in 8 patients with arthrosis. Monocyte TA rose threefold on the first postoperative day in the rheumatoid patients, but was unaltered postoperatively in the arthrosis patients. Granulocyte chemiluminescence doubled in the arthrosis group on the second postoperative day, but was unaltered in the rheumatoid patients. Monocyte chemiluminescence was not influenced by the operation. Thus, leukocytes from the rheumatoid patients responded differently from surgical trauma when compared with leukocytes from the arthrosis patients. This difference may have an impact postoperatively.

Copper and aspirin treatment increase the antioxidant activity of plasma

Copper (Cu) complexes of a number of compounds have increased anti-inflammatory efficacy over the native compound. In the present study, Cu and acetylsalicylic acid (ASA) were administered to rabbits over a one week period. At the end of this time, ocular inflammation was induced by intravitreal injection of endotoxin. ASA caused a slight reduction in the inflammatory response at 24 hours, but this response was not further decreased when Cu was added to the treatment regimen. However, there was a gradual and significant increase in antioxidant activity in the plasma of animals in the combined treatment group which could not be accounted for by a Cu-ASA complex, an increase in the concentration of known plasma protein antioxidants (ceruloplasmin and transferrin) or an increase in superoxide dismutase activity. The compound(s) responsible for this increased activity has a molecular weight greater than 10,000 Da. A large increase in plasma antioxidant activity may have a protective effect in other models of inflammation and provide a mechanism for the proven increase in anti-inflammatory efficacy of Cu-chelates of many compounds.

Superoxide anion production by circulating polymorphonuclear leucocytes in rheumatoid arthritis

In twelve rheumatoid arthritis (RA) patients, receiving only nonsteroid anti-inflammatory therapy, superoxide anion (02-) generation by polymorphonuclear leucocytes (PMNs) was assessed by Cytochrome C reduction. The 02- production by non-activated PMNs in RA patients was significantly higher than in healthy controls. The 02- production by PMNs activated by zymosan and phorbol myristate acetate was significantly lower than in controls. PMNs from controls preincubated with rheumatoid sera generated higher 02- levels than the same PMNs incubated in normal sera.

Free radical activity in type 2 diabetes

Free radical activity has been implicated in the development of diabetic vascular complications in Type 1 diabetes. The aim of the present study was to investigate the levels of free radical scavengers, particularly erythrocyte superoxide dismutase, plasma and erythrocyte lysate thiol, and caeruloplasmin in 22 Type 2 diabetic patients clinically free of complications, and 15 comparable non-diabetic control subjects. The concentration (median (range] of both superoxide dismutase (23 (10-39) vs 45 (25-75) mumol l-1; p less than 0.001) and plasma thiol (374 (172-523) vs 460 (386-595) mumol l-1; p less than 0.01) were reduced in the diabetic group. There were no significant differences in the concentration of erythrocyte lysate thiol (199 (114-520) vs 188 (114-328) mumol l-1) or plasma caeruloplasmin (18 (9-31) vs 24 (6-50) mumol l-1) between the groups. This reduction in superoxide dismutase and the imbalance in the redox status of the plasma and lysate thiol demonstrated is consistent with an increase in free radical activity in Type 2 diabetes.

Free radicals and Graves' disease: the effects of therapy

Plasma thiol (PSH), caeruloplasmin (CP), intracellular lysate thiol (LSH) and superoxide dismutase (SOD) activity were measured in 30 patients with newly diagnosed Graves' disease (GD). Compared to control subjects (C) PSH and SOD were significantly reduced (C vs GD, 507 vs 449 mumol/l, P less than 0.01; 2.1 vs 1.6 mumol/l, P less than 0.01 respectively) and LSH was significantly raised (C vs GD 181 vs 298 mumol/l). Treatment with carbimazole produced a significant rise in LSH and SOD. Propylthiouracil (PTU) treatment raised LSH levels but 131I treatment produced no significant change. All four parameters are involved in different ways in oxygen metabolism and together provide an indication of oxidative stress across the red-cell membrane. In addition LSH is a general radical scavenger and SOD a specific O2- scavenger. In Graves' disease the increased oxidative stress and increased general radical scavenging may result from raised free-radical activity. These changes, which have not previously been reported in Graves' patients, were modified by antithyroid drug therapy, but it is not clear whether this is a direct or indirect effect.

Effects of inflammation on copper antioxidant enzyme levels

Inflammation increases plasma levels of ceruloplasmin, a copper protein with possible antioxidant function. This paper describes modulation of these increases by copper intake, and describes combined effects of inflammation and copper intake on Cu-Zn and extracellular (EC) superoxide dismutase (SOD) activities. Turpentine injections in rats fed 1 of 4 copper levels increased ceruloplasmin activities, but values were sensitively limited by copper intake. Cu-Zn SOD activities in the liver, but not in erythrocytes or lungs, were reduced by inflammation in each dietary copper group. Inflammation in rats fed a standard mixed feed diet reduced plasma EC superoxide dismutase activities measured by inhibition of pyrogallol autoxidation. Different results were obtained with 3 xanthine oxidase based SOD assays which were each subject to assay interference. Studies in humans found a group of rheumatoid arthritis patients to possess relatively low erythrocyte SOD and relatively high ceruloplasmin activities. Activity levels of SOD, but not of ceruloplasmin, increased after 4 weeks of copper supplementation (2 mg/day). The fate of cellular Cu-Zn SOD activity contents in inflamed tissues is largely uninvestigated. However, interleukin-1, a hormone released at inflammation sites, elevated Cu-Zn SOD activities in cultured fibroblasts.

Free radical pathology in chronic arterial disease

The generation of toxic oxygen metabolites is more usually associated with inflammation. However, pathological free radical reactions can cause tissue damage by adversely affecting prostacyclin (PGI2) synthesis allowing initiation of coagulation. We have assessed changes in the red cell defence to toxic oxygen metabolite generation, viz measurement of glutathione concentration (GSH) and superoxide dismutase activity (SOD). GSH and SOD were measured in 20 patients with peripheral arterial disease, 22 patients with vasculitis, and 11 patients with angina, and compared to 17 matched controls. The 53 subjects with arterial disease had significantly lower SOD levels: in contrast GSH levels were significantly higher. Extracellularly plasma thiol levels (PSH) were low and caeruloplasmin (Cp) levels were high. We suggest that free radical pathology exists not only in inflammatory vascular disease but also in atherosclerosis.

Application of the electrochemistry of cytochrome c to the measurement of superoxide radical production

An electrochemical sensor for the measurement of the superoxide anion produced as a result of the respiratory burst of neutrophils is described. The reduction of cytochrome c by the superoxide ion was monitored using a surface-modified gold electrode. The current produced was shown to be superoxide-specific and proportional to the number of neutrophils in both purified neutrophil preparations and plasma.

Superoxide dependent iron release from ferritin in inflammatory diseases

Convincing evidence is presented that oxygen free radicals are involved in the pathogenesis of rheumatoid arthritis (RA). Superoxide is produced by polymorphonuclear leucocytes (PMN) in synovial fluid and by macrophages in the synovial membrane. Tissue damage typical for free radical attack is detected in RA. No absolute deficiency of protective factors is found in RA compared to controls, but the available protection is insufficient to cope with all radicals formed. The toxicity of superoxide is increased by iron. It is doubtful whether a low molecular weight iron pool is present. Superoxide is able to release iron from ferritin, providing a suitable source of iron, for the formation of hydroxyl radicals. This new pathogenetic mechanism stimulates to the application of iron chelators in the treatment of RA. Preliminary results with desferrioxamine were disappointing because of serious side-effects. Hopefully in the future intra-articular injection of iron chelators with better pharmacodynamics will be possible. The interaction of free radicals and ferritin is probably also involved in the pathogenesis of other inflammatory diseases such as systemic lupus erythematosus, hepatitis, and haemochromatosus.

Aspects of the structure, function, and applications of superoxide dismutase

The current status of superoxide dismutase (SOD) is that it is an enzyme with diverse ramifications. This review attempts an understanding of SOD as a structural, functional, and biological entity. Accordingly, the review is in three parts. The first part discusses SOD in terms of protein structure, proceeding from primary to secondary and three-dimensional structure for the three forms of SOD: copper/zinc SOD, manganese SOD, and iron SOD. This is the order of structural knowledge of the enzyme. Iron SOD is an enzyme of prokaryotes and some higher plants. Manganese SOD is an enzyme of prokaryotes and eukaryotes. Copper/zinc SOD is an enzyme of eukaryotes and certain prokaryotes. The evolutionary relationships of the three forms of SOD, the status of the copper/zinc SOD gene in prokaryotes, and the cloning and sequencing of SOD genes are discussed. The second part of the review deals with the catalytic mechanism of SOD in the three forms of the enzyme. Structural and mechanistic conclusions from various spectroscopic studies are critically considered. A detailed picture is given of the active site of copper/zinc SOD. The third part is a review of SOD in the general context of oxygen toxicity. After consideration of the question of superoxide toxicity and superoxide pathology, several areas in which SOD has been investigated or used as a tool in a biochemical, pharmacological, or clinical context are discussed, including population genetics; trisomy 21; development and senescence; the nutritional copper, zinc, and manganese status; hemolysis and anemia; oxygen toxicity in the lung and nervous system; inflammation, autoimmune disease and chromosome breakage, ischemia and degenerative changes; radiation damage; and malignancy. A comprehensive picture is given of measurements of SOD activity in disease states, and the question of superoxide-related disease is considered at several points.

Early and late changes in sulphydryl group and copper protein concentrations and activities during drug treatment with aurothiomalate and auranofin

Superoxide dismutase activity (SOD), plasma and lysate thiol concentrations (PSH and LSH), and caeruloplasmin oxidase activity (CP) reflect the underlying reduction-oxidation imbalance associated with rheumatoid arthritis (RA), and are believed to be involved in the protection of the cell against free radical activity. The early and late changes in these parameters have been observed and compared with standard clinical and biochemical assessments of disease activity in 90 patients with active RA, randomly assigned to receive either sodium aurothiomalate, auranofin, or auranofin placebo. An index based on clinical criteria was used to identify patients as responders or non-responders after 24 weeks of therapy. In the first six weeks of treatment a change in SOD activity and LSH concentration in a direction away from controls was followed by a return towards control levels in responders only. This suggests that in RA evidence of clinical improvement induced by gold drugs is preceded by an initial biochemical response in an inflammatory direction. The extracellular parameters PSH and CP did not show the same early response, but PSH levels in responders showed a slower change towards normal values, though at no time were values obtained that might suggest a complete remission. Thus the intracellular parameters appear to reflect an early effect of the drugs on cells which may possibly be of use in predicting the outcome of therapy, whereas the extracellular parameters provide confirmatory evidence for an eventual improvement.

Studies of the effect of D-penicillamine and sodium aurothiomalate therapy on superoxide anion production by monocytes from patients with rheumatoid arthritis: evidence for in vivo stimulation of monocytes

The capacity of monocytes from patients with rheumatoid arthritis to generate superoxide anion in vitro after stimulation with serum treated zymosan (STZ) or IgG treated zymosan (IgTZ) was studied before and during therapy with penicillamine (n = 9) or sodium aurothiomalate (AuTM) (n = 12). Significant increases in rates of STZ (p less than 0.01) and IgTZ (p less than 0.02) stimulated superoxide anion production were seen after successful therapy (14 patients), which were paralleled by a significant increase in serum thiol levels. Patients who did not respond clinically to therapy (n = 4) showed a smaller mean increase in serum thiol levels and had high mean rates of in vitro superoxide production before and after second-line therapy. Three patients were withdrawn from the study. The data suggest that successful therapy with penicillamine or AuTM may be associated with monocyte activation, and possible mechanisms are discussed.

Copper and inflammation--a possible rationale for the pharmacological manipulation of inflammatory disorders

Acute and chronic inflammations are characterized, among other features, by changes in the metabolism of copper and by a widespread responsiveness to the therapy with copper-containing molecules. The exact map of inflammation-induced copper movements as well as the role played by the metal in the pathogenesis of inflammatory disorders are, however, far from being clear, and this is especially true in the case of chronic processes. Nevertheless the present knowledge suggests that the "copper approach' may provide a new way for coping with the problem of anti-inflammatory/anti-arthritic therapies. The administration of exogenous copper, and the in vivo manipulation of the endogenous metal levels are proposed as two possible therapeutic strategies, not necessarily mutually exclusive. For a better understanding of the value of such an approach, further research work is needed, especially to attain a more detailed know-how on the involved chemical forms, distribution and functions of copper in both normal as well as inflamed organisms.

Human erythrocyte superoxide dismutase activity during deep diving

As the practical use of high pressure oxygen (HPO) in clinical medicine and the offshore industries accelerates, knowledge of its toxic nature becomes essential. In this study, divers' erythrocyte superoxide dismutase (SOD) activity was monitored during high pressure exposure and shown to decrease on average by 20% at depths greater than 150 m. Assay of total red cell SOD protein and activity established that the recorded SOD activity decrement was by loss of immuno-measurable enzyme. No evidence of intra-cellular Heinz bodies was observed. An increase of intra-membrane lipid peroxidation products, within physiological limits, was found, particularly in the denser cell fractions. Using previously in vivo pressure stressed cells, experiments at increasing O2 pressures educed that human red blood cells were oxygen "resistant" up to ten times the normal atmospheric pressure, 0.021 MPa (0.21 bar). Thereafter, a loss in SOD enzyme activity occurred with hemolysis during the in vitro decompression procedure.

Etiology of rheumatoid arthritis

Definite genetic associations with immunological cooperative HLA-D(R) antigens have been demonstrated for rheumatoid arthritis (RA). Microbial etiology has not been proven, but some hope for the supporters of this view is still given by small viruses, plasmids of enteric bacteria or perhaps oncogen-like DNA-sequences. Yet, electrophoretical analysis of membrane proteins or surface glycoproteins of RA synovial cells does not show any differences compared to reference cells. Autoimmunity to several tissue elements has been demonstrated, but most of it is of secondary nature. Antigenicities of type II and III collagens are probably only contributory factors for HLA-DR4 positive individuals. Proteoglycans or minor cartilage collagens have not been extensively studied, so far. Endocrine, dietary or psychological influences might be triggering events for otherwise 'preloaded' individuals.

Low selenium level in severe rheumatoid arthritis

Serum selenium concentrations were measured in 87 patients with rheumatoid arthritis. The serum selenium levels of the whole group of patients was significantly reduced (70.2 +/- 13.3 micrograms/l, p less than 0.001) when compared with the reference material (79.8 +/- 10.6 micrograms/l). However, the reduction was not equally pronounced in three groups of patients representing different courses of the disease. One group with an active, disabling disease of long duration had a very reduced serum selenium level (63.7 +/- 14.1 micrograms/l, p less than 0.001). Another group, with a protracted but mild disease had a slightly reduced level (74.1 +/- 10.8 micrograms/l, p less than 0.01), and a group with mild disease of short duration had a slightly but not significantly reduced selenium level (75.9 +/- 10.8 micrograms/l, p less than 0.1). Significant correlation was found between serum selenium and the number of joints with limitation of motion, number of joints with active arthritis, haemoglobin concentration and IgG concentration. No correlation was found between serum selenium and disease duration, morning stiffness, ESR, C-reactive protein, rheumatoid factor titre, serum albumin, IgM and IgA. Selenium is part of the enzyme glutathione peroxidase that catabolizes peroxides which are suggested to be actively involved in inflammation. A low selenium level may thus be a further factor in the pathogenesis of rheumatoid arthritis.

Protective factors against oxygen free radicals and hydrogen peroxide in rheumatoid arthritis synovial fluid

Oxygen free radicals are probably involved in the pathogenesis of rheumatoid arthritis (RA). The enzymes involved in protection against oxygen free radicals and H2O2 (superoxide dismutase, catalase, and glutathione peroxidase) were measured. Superoxide dismutase was not increased, glutathione peroxidase was slightly and catalase was strongly elevated in RA synovial fluid (SF) compared with control SF. Although these enzymes are present in SF, the activities are insufficient to protect against oxygen free radicals and H2O2. In contrast to transferrin, ferritin was increased in RA synovial fluid. Ceruloplasmin was also elevated. When rat liver microsomes were used as a target for oxygen free radicals, serum and SF were both protective. Gel filtration experiments showed that the fraction pattern in which there was maximal protective potential against lipid peroxidation corresponded closely to the level of ceruloplasmin. After removal of ceruloplasmin from serum or SF, about 70% of the protective capacity disappeared. It is concluded that ceruloplasmin is an important protector against oxygen free radicals.

Glutathione and selenium in rheumatoid arthritis

The concentration of selenium in serum (S-Se) was studied in 20 patients and glutathione in erythrocytes (E-GSH) in 16 patients with rheumatoid arthritis (RA) at onset and after 3 and 6 months of antirheumatic therapy with aurothiomalate (19 cases) or with D-penicillamine (one case). The values were compared to those of age and sex matched healthy controls. S-Se was significantly (p less than 0.01) lower in RA patients at the onset of the trial, but increased to the level of the controls during the follow-up. On the other hand, there was no difference in E-GSH between the patients and their controls before the onset of antirheumatic medication but the increase in E-GSH of RA patients during the trial was highly significant (p less than 0.001). Nevertheless, neither S-Se nor E-GSH correlated to changes in clinical or laboratory indicators of disease activity or to the development of new erosions in X-ray. It is concluded that changes in rheumatoid activity or disease progress occur independently of changes in S-Se or E-GSH.

Monocyte superoxide anion production in rheumatoid arthritis: preliminary evidence for enhanced rates of superoxide anion production by monocytes from patients receiving penicillamine, sodium aurothiomalate and corticosteroids

In-vitro studies of superoxide (O-2) anion production by blood monocytes after stimulation with either serum treated zymosan (STZ), IgG treated zymosan (IgGTZ), or fluoride ion (F-) were performed on cells from normal controls (n = 22) and patients with classical or definite rheumatoid arthritis (RA) (n = 35). Twenty-two of the patients were on nonsteroidal anti-inflammatory drugs (NSAID) alone and 13 were on either sodium aurothiomalate, penicillamine, corticosteroids, or a combination. Monocytes from RA patients on 'second-line therapy' showed significantly increased rates of O-2 release in response to STZ compared with normal controls, but no increase was seen in monocytes from patients on NSAID alone. With IgGTZ as the stimulus, rates of O-2 release were increased in monocytes from patients on NSAID alone compared with normal controls (p less than 0.02), but were increased to a greater extent in monocytes from patients on second-line therapy (p less than 0.01). There were no differences in basal unstimulated O-2 production and no differences after stimulation with F-. The enhanced release of O-2 by monocytes from patients on second-line therapy could not be attributed to increased disease activity and may be an effect of therapy.