Heightened free radical activity in blacks with chronic pancreatitis at Johannesburg, South Africa

Four indices of free radical activity were measured in fasting serum/plasma samples from 14 consecutive blacks with clinically quiescent chronic pancreatitis and 15 outwardly healthy hospital personnel at Soweto, the township near Johannesburg in South Africa. The patients had higher serum levels than did controls of lipid isomerisation (P < 0.002) and peroxidation (P < 0.05) markers, with lower plasma levels of glutathione (P < 0.0001) and bioactive fraction of vitamin C (P < 0.002). Lipid peroxide and non-bioavailable vitamin C concentrations in Sowetan patients were significantly higher than in their counterparts from Manchester, UK (P < 0.0001, P < 0.0005, respectively). These differences mirrored those in controls in that outwardly healthy Sowetans had much higher serum lipid peroxide levels than Manchester controls (P < 0.001) and much lower plasma concentration of vitamin C (P < 0.001) and hence of the bioavailable fraction ascorbate (P < 0.0002). Heightened free radical activity is thus a common denominator in chronic pancreatitis irrespective of geography, or putative aetiological factors whether alcoholism or idiopathic, since that ratio was approximately 95:5 at Johannesburg and 50:50 at Manchester. The further finding of subclinical oxidative stress in Sowetan controls and the endemic nature of chronic pancreatitis in that area supports the hypothesis that oxidative stress may be involved in its pathogenesis.     

Hereditary caeruloplasmin deficiency, dementia and diabetes mellitus

We report two brothers with complete caeruloplasmin deficiency.The brothers presented with dementia and diabetes mellitus.Twelve relatives have partial caeruloplasmin deficiency. Thereis no copper overload. Transmission is autosomal recessive.DNA analysis showed genetic linkage between the deficiency andvarious polymorphic markers flanking the caeruloplasmin geneon chromosome 3q25. This is consistent with a mutation of thecaeruloplasmin gene. Caeruloplasmin catalyses the oxidationof ferrous iron to ferric iron. Both brothers have low serumiron and increased liver iron. The index patient was given caeruloplasmin-containing,fresh-frozen plasma. A dose of 2.6 mg caeruloplasmin increasedserum iron from 5 µM/l to 10 µM/l. A dose of approximately72 mg increased serum iron from 5 µM/l to 19 µM/lThe abnormal serum and liver iron levels, and the caeruloplasmin-inducedrise in serum iron, confirm a previous suggestion that caeruloplasminmaintains the normal rate of flow of iron from store to transferrin.Dementia and diabetes mellitus have been described in only oneother homozygote. The absence of copper overload, and the linkageof the deficiency with chromosome 3q25, distinguish this conditionfrom Wilson's disease.     

Increased plasma copper in patients with homocystinuria due to cystathionine β-synthase deficiency

We measured blood copper-containing proteins and plasma total copper in 15 patients with homocystinuria (14 with cystathionine β-synthase deficiency and one with abnormal cobalamin metabolism), in 13 heterozygotes for cystathionine β-synthase deficiency, and in 44 normal subjects. Plasma total copper was increased in patients with cystathionine β-synthase deficiency compared with age- and sexmatched controls; the ratio was 1.41 ± 0.14 for females and 1.39 ± 0.15 for males (means ± SD). This was due to corresponding increases in caeruloplasmin concentrations, but levels were unrelated to total plasma homocysteine. Erythrocyte superoxide dismutase levels were normal. The heterozygotes had normal plasma copper and caeruloplasmin levels.The increased copper and caeruloplasmin may contribute to the precocious atherogenesis occurring in homocystinuria by decreasing the adhesion of vascular endothelial cells to the intima. It is unlikely that decreased lysyl oxidase activity due to chelation of copper by homocysteine is important for the pathogenesis of the connective tissue defect in homocystinuria.     

Plasma ascorbate levels and inhibition of the antioxidant activity of caeruloplasmin.

1. The copper-containing protein caeruloplasmin has several oxidase activities. 2. Its ability to catalyse the oxidation of ferrous ions to the ferric state (ferroxidase activity) makes it an important antioxidant in vivo. 3. Recent reports have suggested that oral supplementation with vitamin C can inhibit the oxidase activities of caeruloplasmin. 4. As expected, damage to DNA and membrane lipids was stimulated by mixtures of iron salt and ascorbate, and this damage could be inhibited by caeruloplasmin provided the molar ratio of ascorbate to caeruloplasmin was kept sufficiently low. 5. When the molar ratio of ascorbate to caeruloplasmin was greater than 200 substantial loss of ferroxidase antioxidant activity occurred. 6. It is unlikely, however, that oral supplementation with vitamin C can raise plasma levels sufficiently to inhibit caeruloplasmin activity in vivo.     

Evidence of toxic metabolite stress in black South Africans with chronic pancreatitis

We report the results of a further study to test our hypothesis that toxic metabolite stress is germane to heightened free radical activity and hence to the genesis of chronic pancreatitis. Consecutive black South African patients with clinically quiescent chronic pancreatitis were studied, provided that the diagnosis had been made within the previous 2 years and that they did not have overt liver disease. All of them had been advised to stop drinking alcohol. Analysis of an early morning sample of urine showed a lower ratio of inorganic to ester sulphate (P < 0.001) and a higher ratio of d-glucaric acid to creatinine (P < 0.02) in the group of 14 patients than in 15 local controls, while plasma analysis showed a lower concentration of glutathione (GSH) in the patients (P < 0.001). This evidence of increased utilisation of phase II conjugative pathways of xenobiotic disposal was in keeping with on-going toxic metabolite stress from heightened phase I oxidative metabolism in the group of patients. Parallel studies of theophylline pharmacokinetics showed heightened drug clearance compatible with induced cytochrome P-4501A2 in two patients, whereas increased activity of γ-glutamyl transferase in serum suggested persisting induction of P-4502E1, as by ethanol, in several others. The contemporaneous increases in free radical activity and utilisation of xenobiotic disposal pathways in Sowetan Africans with chronic pancreatitis is in line with the toxic metabolite concept of disease pathogenesis.     

Toxicity associated with iron overload found in hemochromatosis: possible mechanism in a rat model.

Hemochromatosis is characterized by pathologic iron overload which often leads to various pathological conditions. The mechanism by which excess iron induces these conditions is not clearly understood. Using rats as the model, this investigation was conducted to explore the mechanism of toxicity associated with iron overload. Sprague-Dawley male rats were fed a 3% carbonyl iron-supplemented diet for eight weeks to achieve iron accumulation. Liver iron reached approximately 2 mg/g which is more than 16 times the control values (mean +/- SD, 0.12 +/- 0.02 mg/g, p < 0.001). Serum iron was consistently higher in the experimental rats (mg/L): 3.41 +/- 0.58 versus 1.89 +/- 0.18, p < 0.001. The high levels of iron accompanied enhanced oxidative damage in the hepatic nuclear DNA when 8-hydroxy-2'-deoxyguanosine (8-OHdG) was measured as a product of DNA oxidation. The levels of 8-OHdG in the experimental samples were significantly higher than the controls (8-OHdG X 10(-5)/dG): 4.22 +/- 1.82 versus 1.84 +/- 0.33, p < 0.05. The results of serum enzyme assays suggest that iron overload caused mild hepatocellular damage: alanine transaminase significantly increased; lactate dehydrogenase did not change; alkaline phosphatase decreased. Since the accumulation of 8-OHdG in the nuclear DNA is highly deleterious to cells, these data suggest oxidative damage in the nuclear DNA may be a critical factor in inducing diseases associated with iron overload.     

Serum antioxidant activity in normal and abnormal subjects

Serum oxidant activity (AOA) was correlated with the serum caeruloplasmin and serum copper concentration and with the total and available serum iron-binding capacity in 313 normal and abnormal subjects. In all groups except in patients with Wilson's disease (hepatolenticular degeneration) there was a highly significant direct correlation between serum AOA and serum caeruloplasmin concentration. A statistically significant direct correlation between serum AOA and the available iron-binding capacity of serum was found only in normal subjects and in children with thalassemia major and iron overload. There was no correlation between serum AOA and the serum tocopherol concentration in any of the groups studied.     

Copper distribution among serum proteins in paediatric liver disorders and malignancies

Fractionation of normal serum on Sephadex G-150, followed by determination of copper, caeruloplasmin and albumin concentrations, indicated that only approximately 71% of total serum copper was associated with caeruloplasmin; less than previously reported values. Seven per cent was associated with a high molecular weight protein, designated 'transcuprein', 19% with albumin and 2% with amino acids. Compared with adult serum the concentrations of caeruloplasmin and of copper associated with caeruloplasmin were low both in serum from neonates and in serum from patients with symptomatic Wilson's disease. However, in contrast to the neonate, Wilson's disease patients exhibited a raised total serum copper and raised non-caeruloplasmin-copper. In Indian Childhood Cirrhosis serum caeruloplasmin and caeruloplasmin-copper levels were normal, whilst the non-caeruloplasmin-copper was raised. Elevated non-caeruloplasmin-copper in Wilson's disease and Indian Childhood Cirrhosis may therefore represent an overspill into the serum from a copper-laden liver. Children with malignancy showed increased serum concentrations of copper and caeruloplasmin. Both caeruloplasmin-bound and non-caeruloplasmin-bound copper concentrations were elevated. It remains to be determined whether increased 'transcuprein'- and albumin-bound copper result from a sequestering of copper released from peripherally utilized caeruloplasmin, or are associated with increased rates of caeruloplasmin synthesis.     

Right ventricular volumes and function in thalassemia major patients in the absence of myocardial iron overload

Aim

We aimed to define reference ranges for right ventricular (RV) volumes, ejection fraction (EF) in thalassemia major patients (TM) without myocardial iron overload.

Methods and results

RV volumes, EF and mass were measured in 80 TM patients who had no myocardial iron overload (myocardial T2* > 20 ms by cardiovascular magnetic resonance). All patients were receiving deferoxamine chelation and none had evidence of pulmonary hypertension or other cardiovascular comorbidity. Forty age and sex matched healthy non-anemic volunteers acted as controls. The mean RV EF was higher in TM patients than controls (males 66.2 ± 4.1% vs 61.6 ± 6%, p = 0.0009; females 66.3 ± 5.1% vs 62.6 ± 6.4%, p = 0.017), which yielded a raised lower threshold of normality for RV EF in TM patients (males 58.0% vs 50.0% and females 56.4% vs 50.1%). RV end-diastolic volume index was higher in male TM patients (mean 98.1 ± 17.3 mL vs 88.4 ± 11.2 mL/m2, p = 0.027), with a higher upper limit (132 vs 110 mL/m2) but this difference was of borderline significance for females (mean 86.5 ± 13.6 mL vs 80.3 ± 12.8 mL/m2, p = 0.09, with upper limit of 113 vs 105 mL/m2). The cardiac index was raised in TM patients (males 4.8 ± 1.0 L/min vs 3.4 ± 0.7 L/min, p < 0.0001; females 4.5 ± 0.8 L/min vs 3.2 ± 0.8 L/min, p < 0.0001). No differences in RV mass index were identified.

Conclusion

The normal ranges for functional RV parameters in TM patients with no evidence of myocardial iron overload differ from healthy non-anemic controls. The new reference RV ranges are important for determining the functional effects of myocardial iron overload in TM patients.     

Dietary Intake and Serum Levels of Iron in Relation to Oxidative Stress in Breast Cancer Patients

Iron may induce oxidative stress via production of reactive oxygen species, facilitating mammary carcinogenesis. This study investigated the role of iron in relation to oxidative stress as a potential risk factor in the development of breast cancer (BC). BC patients (n = 121) and healthy age-matched controls (n = 149) were entered into the study. Iron and antioxidant vitamins intakes were estimated using a quantitative food frequency questionnaire. Thirty one subjects from each group provided blood samples for measurement of serum iron, plasma malondialdehyde (MDA) and ferric reducing ability of plasma (FRAP). Total and non-heme iron intake of BC patients were lower than those of the controls. However, the serum iron level was significantly higher in BC patients. Plasma MDA levels were also significantly higher in BC patients whereas no significant difference in FRAP values were observed between the two groups. Log-transformed serum iron concentration showed no significant correlation with MDA or FRAP. These results suggest that serum iron overload may be a breast cancer risk factor possibly due to increased oxidative stress.     

Elevated fasting cholecystokinin levels in pancreatic exocrine impairment: evidence to support feedback regulation

Previous studies have suggested that intraduodenal protease suppression of pancreatic exocrine secretion may be mediated through cholecystokinin (CCK) release. Our study compares basal plasma immunoreactive CCK concentrations in normal human subjects with those obtained in patients with chronic pancreatitis. Fasting plasma samples were collected from 18 normal subjects and from 18 patients with chronic pancreatitis. Eight patients had mild to moderate pancreatic exocrine impairment, and 10 had severe exocrine insufficiency. Venous plasma immunoreactive CCK concentrations were measured with two distinct peptide region-specific antibodies. Basal plasma CCK concentration in controls was 14.3 +/- 1.3 fmol/ml (mean +/- SEM), a value significantly less than that obtained in all patients with chronic pancreatitis, 30.1 +/- 4.0 fmol/ml (p less than 0.001). Patients with mild to moderate impairment had a fasting plasma CCK concentration of 32.8 +/- 7.9 fmol/ml (vs. control p less than 0.01), and those with severe disease 27.9 +/- 3.6 fmol/ml (vs. control p less than 0.001). In five patients with mild to moderate impairment of exocrine function and pancreatic extract-responsive abdominal pain, there was a 39 +/- 11% decrease in basal CCK levels during extract therapy (p less than 0.05). Results of this study indicate that pancreatic exocrine impairment is associated with elevated basal CCK levels, which may reflect a failure to provide feedback downmodulation of CCK release.     

Copper, zinc and copper/zinc ratio in chronic pancreatitis and pancreatic cancer

Serum copper and zinc levels and their ratio were evaluated in 48 control subjects, 29 patients with pancreatic cancer, 46 with chronic pancreatitis and 32 with extra-pancreatic diseases, with the purpose of ascertaining modifications in chronic pancreatic disease. Hepatic involvement and age were also investigated as possible factors influencing results. Cu/Zn ratio was found to be significantly increased in pancreatic cancer (2.66 +/- 0.16, mean +/- SE) as compared to controls (1.39 +/- 0.06, p less than 0.001), chronic pancreatitis (1.82 +/- 0.09. p less than 0.001) and extra-pancreatic diseases (1.81 +/- 0.18, p less than 0.001), but without practical clinical value. Serum zinc levels appear to decrease with age, while copper and Cu/Zn ratio increase. However, covariance analysis demonstrated that age does not play an important role in influencing copper and Cu/Zn ratio. A decreased liver synthetic function, at least in part age-related, seems to be an additional factor in decreasing serum zinc values.     

Effect of iron supplementation in women with chronic cough and iron deficiency

Aims: Chronic cough is more frequent and severe in women than in men. Women often have decreased iron stores, because of menses and pregnancies. We investigated if iron deficiency has a role in chronic cough by increasing airway sensitivity to inhaled irritants. Methods: Twenty‐two non‐smoking women with chronic unexplained cough and iron deficiency (serum ferritin below 15 ng/ml) were examined in baseline, after 2 months empiric treatment with anti H1‐histaminic drug and proton pump inhibitor, and after iron supplementation (330–660 mg iron sulphate tablets daily) for 2 months. Outcome measures were cough visual analogue scale (VAS), and histamine thresholds of the larynx (PC25MIF50, concentration causing 25% in MIF50), bronchi (PC20FEV1) and cough (PC5cough). Results: Mean serum ferritin was 9.3 ng/ml (95% CI 7.7–10.9), 13 patients had mild anaemia. All the patients had laryngeal and cough hyperresponsiveness,12 had also bronchial hyperresponsiveness. Empiric treatment produced no significant effect, whereas iron supplementation improved cough VAS from 4.03 (3.6–4.47) to 2.6 (1.9–3.27), p < 0.0001, PC20FEV1 from 10.04 mg/ml (5.37–18.77) to 22.2 (11.7–41.8), p < 0.001, PC25MIF50 from 3.09 mg/ml (1.9–4.9) to 11.9 (7.3–19.4), p < 0.001 and PC5cough from 2.1 mg/ml (1.2–3.6) to 8.8 (5.2–15.1), p < 0.001. Conclusion: In women with unexplained chronic cough unresponsive to targeted treatment, airway and cough hyperresponsiveness may be sustained by iron deficiency. Healthy women with chronic cough should be checked for iron deficiency as iron repletion may resolve such disturbing symptom.     

Transfusional iron overload in patients undergoing dialysis: treatment with erythropoietin and phlebotomy

Five patients undergoing long-term hemodialysis with transfusional iron overload received treatment for 18 weeks with a regimen of recombinant human erythropoietin (150 U/kg) and regular phlebotomy to maintain the hematocrit value at 25% and reduce the total body iron burden. In the 149 phlebotomy sessions performed in these patients, a mean of 228 +/- 8 ml (mean +/- SEM) of whole blood was removed; it had a hematocrit value of 27.7% +/- 0.2%. The iron content of the erythrocytes removed (erythrocyte iron concentration, 787 +/- 11 micrograms/ml in 133 samples) accounted for more than 99% of the total iron removal by phlebotomy. Serum iron (serum iron concentration, 1.57 +/- 0.09 micrograms/ml in 65 samples) accounted for an insignificant fraction of the total iron removed. The iron removed at each phlebotomy session averaged 49.1 +/- 2.0 mg, similar to the amount of iron removed with deferoxamine administration in patients undergoing dialysis who had iron overload, but without the potential for adverse side effects reported with long-term deferoxamine therapy. Total iron removal during the 18 weeks of this study ranged from 732 to 2797 mg. Mean serum ferritin level decreased from 3189 +/- 1076 micrograms/L to 1676 +/- 342 micrograms/L (p less than 0.02, Wilcoxon signed rank test). When compared with a group of five patients without transfusional iron overload who received recombinant human erythropoietin and did not undergo therapeutic phlebotomy, the patients with iron overload had much greater iron losses and a larger decrease in serum ferritin levels.(ABSTRACT TRUNCATED AT 250 WORDS)     

Western blot analysis in patients with hypocaeruloplasminaemia

Inherited copper toxic disease, Wilson's disease, is an autosomal recessive disorder arising from a defect in biliary copper excretion. Although there are several pathognomonic clinical features, such a multisystem disease can be difficult to diagnose, particularly in the early stages of copper toxicity. Even measurements of serum copper and caeruloplasmin, the major copper-transporting protein typically reduced in Wilson's disease, may mimic other metabolic conditions such as Menke's disease and chronic active hepatitis. We have previously shown that the major biliary isoform of copper-transporting protein is 125 kDa caeruloplasmin, and this is always absent in the bile of Wilson's disease patients. In this paper we describe Western blot analysis of molecular species of caeruloplasmin in hypocaeruloplasminaemia, which can distinguish between the overlap which occurs in Wilson's disease homozygotes, heterozygotes and other conditions mimicking Wilson's disease. This may be useful for identifying patients with low plasma caeruloplasmin concentrations, and hepatic or neurological clinical features which may also be found in Wilson's disease.      

Association between oxidative stress and changes of trace elements in patients with breast cancer

OBJECTIVES: To investigate the association between oxidative stress and certain trace elements in the blood of breast cancer patients. DESIGN AND METHODS: Malondialdehyde (MDA) was measured in serum of patients with breast cancer (n = 35) and controls (n = 35) by high performance liquid chromatography. Trace elements were determined by atomic absorption spectrophotometry. RESULTS: In the present study, significantly increased lipid peroxidation, measured as MDA, was demonstrated in the serum of breast cancer patients (p < 0.01). The concentrations of zinc and iron remained unaltered. However, the mean serum copper level in patients with breast cancer was significantly higher than the control group (p < 0.01). In addition, the mean serum selenium level in patients with stage III was significantly lower than the control group (p < 0.05). Moreover, a positive correlation was also observed between copper and MDA levels in the patient group but not in the control group. CONCLUSION: In the present study, the presence of an association between oxidative stress and trace elements was observed in patients with breast cancer. We suggest that increased oxidative stress in patients with breast cancer may result from changes in the levels of certain trace elements.     

New aspects of copper and iron metabolism in the myelodysplastic syndromes

BACKGROUND: Myelodysplastic syndrome (MDS) is an iron overload condition. Copper deficiency itself might induce dysplastic changes and iron overload. The relationship between the iron and copper metabolism is analyzed in MDS patients. METHODS: Copper, iron and ceruloplasmin levels were established, and transferrin saturation determination and HFE mutation analysis were performed in 32 MDS patients. RESULTS: Eleven of 32 MDS patients were copper deficient. A decreased copper level occurred together with a significantly elevated iron level and transferrin saturation and in 45% HFE gene mutation. In the normal copper group, twice as many patients had a decreased rather than an elevated iron content and carried the wild-type HFE gene rather than the mutant. CONCLUSIONS: Copper deficiency is a frequent finding in MDS. It is desirable to include copper level determination in the initial workup of MDS.     

Ferrous ions detected in cerebrospinal fluid by using bleomycin and DNA damage.

1. During pathological states of iron-overload or oxidant stress, low-molecular-mass iron can become available within extracellular fluids. 2. This iron would be converted to the ferrous state were it not for the protective anti-oxidant protein caeruloplasmin. 3. The ferrous-ion-oxidizing activity of caeruloplasmin rapidly converts ferrous ions back to the less reactive ferric state so that they can bind to available binding sites on transferrin. 4. Cerebrospinal fluids, however, often appear to contain low-molecular-mass iron, high levels of ascorbate and low levels of ferroxidase activity with little or no iron-binding capacity. 5. When iron ions are present in cerebrospinal fluid they are therefore likely to be in the ferrous state. 6. The development and application of an assay to speciate and measure ferrous ions in simple aqueous solution and their redox cycling activity in biological fluids is described.     

Prevalence, causes and effects of increased iron storage in patients with kidney transplantation

Patients on chronic hemodialysis often need blood transfusions due to erythropoietin deficiency. Even after successful kidney transplantation iron overload may persist. Former histological studies have revealed siderosis of the liver in 69% of all patients whose serum ferritin was above 1100 ng/ml. The aim of the present study was to evaluate the influence of iron overload on liver function. In 146 symptom free patients with renal allografts serum ferritin was determined to detect possible iron overload. Serum ferritin between 4 and 5480 ng/ml were found (women: 358.7 +/- 105.3; men 282.4 +/- 63.3 ng/ml; x +/- SEM). Twelve patients (8.1%) had ferritin levels higher than 1100 ng/ml. These twelve patients as well as another group of eight patients with renal allografts whose serum ferritin was known to be higher than 1100 ng/ml were included for further evaluation. Their data were matched and compared with those of a control group also patients with renal allograft (same age and sex) whose serum ferritin was lower than 1100 ng/ml. Transaminases (SGPT 22.6 +/- 3.6 vs. 15.4 +/- 6.0 U/l; SGOT 14.7 +/- 2.0 vs. 13.0 +/- 4.8 U/l) and plasma glucose (90.5 +/- 7.1 vs. 76.8 +/- 3.7 mg/dl) were found to be significantly higher (p less than 0.05) in patients with serum ferritin levels above 1100 ng/ml. Elevated transaminases were significantly more frequent in patients with high serum ferritin (9 vs. 2; p less than 0.02) as compared with the control. Ferritin levels significantly correlated with the number of preceding blood transfusions (p less than 0.002). Hbs-persistence was detected in six out of 20 patients with high ferritin levels but only in one out of 20 in the control group (p less than 0.05) whereas anti-Hbs prevalence was not different in the two groups. These data indicate that chronic iron overload should be considered as a possible cause of chronic liver disease in patients with renal allografts.     

d-penicillamine reduces serum oxidative stress in Alzheimer's disease patients

BACKGROUND: Several lines of evidence address the emerging role for copper in Alzheimer's disease (AD) for sustaining oxidative mechanisms. Studies indicate that peripheral markers of oxidative stress in AD patients could be informative about the pathophysiology of this brain condition. Here, we present a pilot study examining the efficacy of the copper-chelating agent d-penicillamine in reducing oxidative stress in AD patients. DESIGN: Serum levels of copper sampled in AD patients and healthy controls indicate a copper homeostasis imbalance in AD. On this basis, 34 AD patients were enrolled in a 6-month, double-blind, placebo-controlled trial with the copper d-penicillamine-chelating agent. Nine patients for each group completed the trial. Oxidative stress, trace metals and clinical parameters were evaluated. RESULTS: At the start of the study (t0) total peroxides and copper serum content of AD patients were higher (P < 0.0001, P < 0.0001, respectively) and antioxidants were lower (P < 0.05) than in healthy controls. Copper and peroxides were correlated in the AD population (Pearson's r = 0.61, P < 0.001). After treatment with d-penicillamine, the extent of oxidative stress (P < 0.05) was decreased, but no difference was observed in the rate of cognitive decline. CONCLUSION: Data from this pilot study suggest that copper could play a role in the production of peroxides in AD, and that d-penicillamine has an effect in reducing oxidative damage, however, results are still inconclusive in terms of drug efficacy on the clinical progression of AD. Studies with larger cohorts are needed to elucidate the real effectiveness of d-penicillamine treatment in AD.