Renovascular disease: effect of ACE gene deletion polymorphism and endovascular revascularization

BACKGROUND

Renal artery stenosis (RAS) is associated with high cardiovascular mortality and significant clinical complications, including resistant hypertension and ischemic nephropathy. Despite availability of endovascular revascularization techniques, determining which patients should undergo revascularization and the timing of the procedure still are controversial. Several studies have reported a higher frequency of the DD genotype of the insertion/deletion (I/D) polymorphism of the angiotensin converting enzyme (ACE) gene in patients with RAS, and one study found higher mortality in patients with the DD genotype. Material and methods We retrospectively studied 100 patients with documented atherosclerotic RAS and evaluated long-term (median follow-up, 28 months) mortality, blood pressure control, and renal function in relation to the ACE genotype and two therapeutic strategies, that is, endovascular treatment with percutaneous renal transluminal angioplasty or stenting (ET group) versus conservative drug therapy (CT group).

RESULTS

Comparison between therapeutic groups showed a higher cumulative probability of survival (86.7% vs 67.1%), better blood pressure control (57.4% vs 29%), and slower decline in renal function (17.9% vs 48.4%) in the ET group. The DD genotype was strongly represented in our study patients (DD, 50%; II, 15.5%; I/D, 34.5%), but bore no relation to mortality, blood pressure control, decline in renal function, or rate of recurrent stenosis.

CONCLUSIONS

Conservative medical treatment of RAS, compared with endovascular treatment, is associated with higher mortality, poorer blood pressure control, and impaired renal function over the long term. Early endovascular treatment enables amelioration of this unfavorable evolution. The DD genotype does not predict clinical outcome of RAS.

Interaction of antibodies against cytomegalovirus with heat-shock protein 60 in pathogenesis of atherosclerosis

BACKGROUND

Infections and autoimmunity have been implicated in the pathogenesis of atherosclerosis. Cytomegalovirus has been shown to contribute to the disease. Autoantibodies against human heat-shock protein (HSP) 60 are present in most atherosclerotic patients, and their titre correlates with disease severity, suggesting that anti-HSP60 might be implicated in disease pathogenesis. We postulated that cytomegalovirus infection might induce antibodies able to bind human HSP60 and to cause endothelial-cell damage.

METHODS

We studied 180 patients with coronary-artery disease, raised high sensitivity C-reactive protein concentrations, and presence or absence of traditional risk factors; 90 patients with coronary-artery disease, normal values for high sensitivity C-reactive protein, and no traditional risk factors; and 98 controls. Individual sera were used to define the relevant epitope of HSP60 by ELISA. Affinity purified IgGs were used to identify endothelial cell-surface ligands by western blot and to induce apoptotic cell death.

FINDINGS

We identified an 11 aminoacid sequence of HSP60 that was recognised by most patients with coronary-artery disease. This peptide shares homology with cytomegalovirus-derived proteins UL122 and US28. The same patients' sera recognised UL122-derived and US28-derived peptides. Purified IgGs against HSP60 and the viral peptides bound non-stressed human endothelial cells and induced endothelial-cell apoptosis by interaction with cell-surface molecules.

INTERPRETATION

During cytomegalovirus infection, antibodies against the virus can arise that are able to crossreact with human HSP60 and cause apoptosis of non-stressed endothelial cells, which is judged a primary event in the pathogenesis of atherosclerosis.

Liver stellate cells and aminoterminal peptide of type III procollagen in chronic hepatitis C treated with interferon

BACKGROUND/AIMS

Fibrogenesis plays a crucial role in development of cirrhosis, and liver stellate cells, activated to myofibroblasts expressing alpha-smooth muscle actin, are responsible for deposition of fibrous matrix; aminoterminal peptide of type III procollagen is a serum marker of active fibrogenesis. Interferon can slow ongoing fibrogenesis in chronic viral hepatitis, but it remains unclear whether the drug acts by a direct effect on stellate cells or by inhibiting the necro-inflammatory process. The aim of this study was to evaluate, in selected cases of chronic hepatitis C, whether changes in stellate cell expression induced by interferon correlated with changes in serum levels of procollagen or with clinical response to the therapy, in order to further investigate the mechanism of interferon's effect on fibrogenesis.

METHODOLOGY

We studied 30 patients with chronic hepatitis C, treated with interferon and followed for more than 6 months. Before and after-treatment evaluation included histological scores for portal activity, lobular activity and fibrosis; immunohistochemical scores for alpha-actin expression by activated stellate cells in liver biopsy; and radioimmunoassay for procollagen in serum. According to the clinical response to interferon, the patients were subdivided into sustained responders, delayed relapsers, early relapsers and non-responders.

RESULTS

We found that alpha-actin scores, portal and lobular activity scores and procollagen levels were all significantly lower after the treatment in responder patients, whereas in non-responders the after-interferon values were not different from the basal values. Moreover we found that the patients who were still clinical responders at the time of after-therapy evaluation, but relapsed subsequently (delayed relap-sers), still showed a pattern of "low fibrogenesis", like the sustained responders. On the contrary, the patients who had already relapsed at the time of after-interferon evaluation (early relapsers) showed a pattern of "high fibrogenesis", like the non-responders.

CONCLUSIONS

Since all the patients had received a similar treatment for a similar period, our results suggest that fibrogenesis activity in a defined time is related to the clinical response present in that time, and is influenced by short-term variations in necro-inflammatory activity induced by interferon, rather than by interferon itself.

Apolipoprotein C-III, metabolic syndrome, and risk of coronary artery disease

Apolipoprotein C-III (apoC-III) is a marker of triglyceride (TG)-rich lipoproteins, which are often increased in metabolic syndrome (MS). The T-455C polymorphism in the insulin-responsive element of the APOC3 gene influences TG and apoC-III levels. To evaluate the contribution of apoC-III levels and T-455C polymorphisms in the coronary artery disease (CAD) risk of MS patients, we studied 873 patients, 549 with CAD and 251 with normal coronary arteries. Patients were classified also as having or not having MS (MS, n = 270; MS-free, n = 603). Lipids, insulin, apolipoprotein levels, and APOC3 T-455C genotypes were evaluated. ApoC-III levels were significantly increased in MS patients, and the probability of having MS was correlated with increasing quartiles of apoC-III levels. MS patients with CAD had significantly higher apoC-III levels than did CAD-free MS patients. The carriership for the -455C variant multiplied the probability of CAD in MS in an allele-specific way and was associated with increased apoC-III and TG levels. Obesity was less frequent in MS carriers of the -455C allele than in MS noncarriers (21.6% vs. 34.8%, P < 0.05). In conclusion, apoC-III-rich lipoprotein metabolism and the APOC3 polymorphism have relevant impacts on the CAD risk of MS patents.

The presence of parvovirus B19 VP and NS1 genes in the synovium is not correlated with rheumatoid arthritis

OBJECTIVE

To amplify both NS1 and VP genes of Parvovirus B19 DNA in synovial membrane (SM) and serum obtained from patients with rheumatoid arthritis (RA) and to analyze whether the presence of viral DNA is correlated with synovitis.

METHODS

DNA obtained from 30 SM and 24 serum samples from RA patients was analyzed using single round-polymerase chain reaction (PCR) and nested PCR for both VP and NS1 genes of parvovirus B19. Twenty-four SM and serum samples from sex and age matched subjects with osteoarthritis (OA) or joint trauma served as controls.

RESULTS

The first round PCR was negative for NS1 in RA samples. After nested PCR, NS1 was detected in the SM of 6/30 patients and of 10/24 controls and in the serum of 4/24 patients and controls. Nested PCR for the VP gene detected viral DNA in the SM of 7/30 patients with RA and of 7/24 of the controls and in the serum of 5/24 patients and of 2/24 controls. Altogether parvovirus DNA was found in the SM of 11/30 (36.6%) patients and of 12/24 (50%) controls and in the serum of 8/24 (33.3%) patients with RA and of 5/24 (20.8%) controls.

CONCLUSION

Our results suggest that the amplification by nested PCR of both NS1 and VP genes is necessary to define the presence of viral DNA in tissue samples and confirm that the presence of parvovirus B19 DNA is similar in RA and control SM, suggesting that simple detection of viral DNA is not sufficient to confirm a link between the virus and RA.

Inhaled nitric oxide protects transgenic SAD mice from sickle cell disease-specific lung injury induced by hypoxia/reoxygenation

Central to the pathophysiology of sickle cell disease are the vaso-occlusive events that lead to tissue damages and life-threatening complications. Lungs are particularly vulnerable to vaso-occlusion because of their specific vasculature. We developed a mouse model of hypoxia/reoxygenation lung injury closely mimicking the lung pathology of patients with sickle cell disease. This model involves the exposure of transgenic sickle cell (SAD) mice to hypoxia (8% oxygen) for 4, 10, and 46 hours followed by 2 hours of reoxygenation. Gene expression profiling of SAD lung tissue pointed to the specific induction of genes involved in the response to ischemic stress and microcirculation remodeling: Hspcb, Hsp86-1, Nfe2l2, Ace, and Fgf7. Hypoxia/reoxygenation also induced a marked increase in bronchoalveolar (BAL) total leukocyte and neutrophil counts, BAL total protein content, and BAL tumor necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6), IL-1alpha, and macrophage inflammatory protein 2 (MIP-2) levels, all indicators of enhanced inflammatory response as compared with control mice. Nitric oxide (NO) was administered to SAD mice. NO (40 ppm) inhalation protected SAD mice from the histopathologic lesions of ischemic/reperfusion lung injury with corresponding normalization and/or modulation of tissue gene expression profiles. Inhaled NO (1) significantly reduced the increase in BAL total protein content, BAL total leukocyte, and neutrophil counts; (2) modulated BAL cytokine network; and (3) did not affect hemoglobin and methemoglobin levels. The present study provides evidences for the beneficial effects of inhaled NO in pulmonary injury induced by hypoxia/reoxygenation in a mouse model of sickle cell disease (SCD) and opens new avenues in drug design based on tissue gene expression profiling.

Results of double-blind placebo-controlled challenge with nickel salts in patients affected by recurrent aphthous stomatitis

BACKGROUND

The aetiology of recurrent aphthous stomatitis (RAS) has so far not been completely clarified. Recently, several studies reported that patients affected by cutaneous diseases (i.e. dermatitis, eczema and urticaria) with positive patch test to nickel have a positive oral nickel challenge.

OBJECTIVE

A retrospective data analysis of patch test and oral nickel challenge in 380 patients (204 women and 176 men) affected by RAS was performed.

PATIENTS AND METHODS

We examined 380 consecutive patients affected by RAS during the period 1990-1999. In 28/380 patients the appearance of their oral symptoms coincided with the fitting of orthodontic appliance, while 352/380 reported that their oral symptoms worsened after the fitting of orthodontic appliance. All patients were studied with the series (European standard series and series for dental materials) for patch tests.

RESULTS

Seventy out of 380 patients (18.4%) presented a contact sensitization to nickel sulphate (positive patch test). In all of these, the orthodontic appliance was replaced with one made of nickel-free materials. All patients were re-examined by the dentist 6 months after the removal of the orthodontic appliance. The symptoms had completely remitted in 28/70 patients, partially had improved in 31/70 patients and had remained unchanged in 11/70 patients. In all patients (n = 70) with a positive patch test to nickel we performed an oral double-blind placebo-controlled challenge (DBPC) test with nickel sulphate. The DBPC was positive in 32/70 patients, 21 of whom had partially improved and 11 had not, even after the replacement of the orthodontic appliance with material not containing nickel. None of the 28 patients in complete remission showed an adverse reaction to oral nickel challenge.

CONCLUSION

The results of this study demonstrate that, in some patients with a positive patch test to nickel sulphate, the perpetuation of RAS can be related to a hypersensitivity to ingested nickel salts, independently of local contact to nickel.

The interaction between MTHFR 677 C-->T genotype and folate status is a determinant of coronary atherosclerosis risk

The 677 C-->T polymorphism in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene interacts with folate status in determining elevated total plasma levels of homocysteine, a risk factor for coronary atherosclerotic disease (CAD). The present study had the following goals: 1) to define the 677 C-->T genotype-specific threshold values of both plasma and RBC folate, associated with hyperhomocysteinemia (>15 micro mol/L); and 2) to determine the risk of CAD among subjects with levels of folate below the genotype-specific threshold considered at risk for hyperhomocysteinemia. We examined 655 subjects, with (433) or without (222) angiographically documented CAD. The MTHFR 677 C-->T genotype-specific threshold values of plasma folate corresponded to the 40th, 30th and 10th percentile in the TT, CT and CC genotype, respectively. A multivariate logistic regression analysis showed that the risk of CAD among subjects with plasma folate levels below the genotype-specific thresholds was 1.6 (95% CI, 1.04-2.46). Similar results were obtained when RBC folate was considered as a measure of folate status (odds ratio = 1.8, 95% CI, 1.03-3.15). A gene-nutrient interaction that defines a higher risk for CAD is determined by folate levels below specific thresholds, which differ depending on the MTHFR 677 C-->T genotype.

Serum levels of soluble CD30 in adult patients affected by atopic dermatitis and its relation to age, duration of disease and Scoring Atopic Dermatitis index

The value of CD30 and the soluble circulating fragment of CD30 (sCD30) for atopic dermatitis (AD) remains unclear. In particular, little is known about the effects of age, duration of disease and Scoring Atopic Dermatitis index (SCORAD) on the levels of serum sCD30 in patients affected by AD. In the present study, we have analysed serum sCD30 levels of adult patients affected by AD. The study's population includes 18 non-smoking outpatients, with a diagnosis of AD. As a control group we studied 18 non-atopic subjects from laboratory staff, matched for sex and age. These subjects had no history of AD, urticaria or seasonal or perennial rhinitis or asthma, and had negative skin prick test to a panel of allergens. The sCD30 serum levels were clearly higher in patients affected by AD (14.2+/-9.0 IU/ml) than in healthy subjects (1.2+/-0.8 IU/ml) (p<0.001). No differences were observed between males and females affected by atopic dermatitis, regarding age, duration of disease and SCORAD. Significant correlations were found between serum levels of sCD30 levels and age (r=-0.55; 95% confidence interval (CI) for r (Fisher's z transformed)=-0.81 to -0.12; p=0.01), duration of the disease (months) (r=-0.64; 95% CI for r (Fisher's z transformed)=-0.85 to -0.24; p=0.004) and SCORAD (r=-0.74; 95% CI for r (Fisher's z transformed)=-0.89 to -0.42; p=0.004). As demonstrated by the close correlation with age, duration of disease and SCORAD, serum levels of sCD30 appear to be an additional marker for the follow-up of AD.

ICA-17043, a novel Gardos channel blocker, prevents sickled red blood cell dehydration in vitro and in vivo in SAD mice

A prominent feature of sickle cell anemia is the presence of dehydrated red blood cells (RBCs) in circulation. Loss of potassium (K(+)), chloride (Cl(-)), and water from RBCs is thought to contribute to the production of these dehydrated cells. One main route of K(+) loss in the RBC is the Gardos channel, a calcium (Ca(2+))-activated K(+) channel. Clotrimazole (CLT), an inhibitor of the Gardos channel, has been shown to reduce RBC dehydration in vitro and in vivo. We have developed a chemically novel compound, ICA-17043, that has greater potency and selectivity than CLT in inhibiting the Gardos channel. ICA-17043 blocked Ca(2+)-induced rubidium flux from human RBCs with an IC(50) value of 11 +/- 2 nM (CLT IC(50) = 100 +/- 12 nM) and inhibited RBC dehydration with an IC(50) of 30 +/- 20 nM. In a transgenic mouse model of sickle cell disease (SAD), treatment with ICA-17043 (10 mg/kg orally, twice a day) for 21 days showed a marked and constant inhibition of the Gardos channel activity (with an average inhibition of 90% +/- 27%, P <.005), an increase in RBC K(+) content (from 392 +/- 19.9 to 479.2 +/- 40 mmol/kg hemoglobin [Hb], P <.005), a significant increase in hematocrit (Hct) (from 0.435 +/- 0.007 to 0.509 +/- 0.022 [43.5% +/- 0.7% to 50.9% +/- 2.2%], P <.005), a decrease in mean corpuscular hemoglobin concentration (MCHC) (from 340 +/- 9.0 to 300 +/- 15 g/L [34.0 +/- 0.9 to 30 +/- 1.5 g/dL], P <.05), and a left-shift in RBC density curves. These data indicate that ICA-17043 is a potent inhibitor of the Gardos channel and ameliorates RBC dehydration in the SAD mouse.

Urinary metabolites of histamine and leukotrienes before and after placebo-controlled challenge with ASA and food additives in chronic urticaria patients

BACKGROUND

The recovery of mediator metabolites from urine has the potential to provide a rapid, safe, and easily available index of release of mediators. We aimed to determine urinary metabolites of both histamine and leukotrienes (LTs) in patients affected by chronic urticaria (CU).

METHODS

Twenty patients with CU were studied. They were selected on the basis of double-blind placebo-controlled challenge (DBPC) with acetyl salicylic acid (ASA) and food additives. Ten patients (group B) were negative to both challenges. Ten patients (group C) presented urticaria and/or the appearance of angioedema during or 24 h after challenge, with reactions to ASA (five patients) or food additives (five patients). We recruited 15 healthy volunteers as controls (group A). During a second challenge, groups B and C were challenged double-blind with a single dose of ASA, or a specific food additive, or placebo. The healthy group was challenged only with a placebo (talc capsule). Patients in groups B and C were challenged twice: with placebo (as groups B1 and C1) and with ASA (groups B2 and C2) or food additives (C2). Four samples of urine were collected; one during the night before the specific or sham challenge (baseline), and three at 2, 6 and 24 h after the challenge. Urinary methylhistamine (N-MH) and LTE4 were analyzed and normalized for urinary creatinine.

RESULTS

For urinary N-MH at baseline, there was a significant difference only between group A and groups B1, B2, C1 and C2 (A vs. B1, P < 0.0001; A vs. B2, P < 0.0001; A vs. C1, P < 0.0001; A vs. C2, P < 0.0001). We detected a significant variation in urinary methylhistamine excretion only in group C2 after 2 h, 6 h and 24 h (P < 0.0001). However, no variations were observed in N-MH excretion rate in the other groups (A, B1, C1) after challenge with placebo, and in B2 after challenge with ASA 20 mg. For urinary LTE4 at baseline no differences were found between the mean values for the different groups. After specific challenge, only C2 patients showed significantly increased excretion rates of urinary LTE4 compared with the other groups challenged with placebo (A, B1, C1), or ASA (B2) (P < 0.0001). No significant correlation was seen between urinary LTE4 and methylhistamine excretion rate in any patients.

CONCLUSION

Our results show that urinary excretion of N-MH and LTE4 is different for CU patients without ASA or food hypersensitivity, compared to those with CU with ASA or food additive hypersensitivity after specific challenge.

Autoantibodies to inner ear and endothelial antigens in Cogan's syndrome

BACKGROUND

Cogan's syndrome is a chronic inflammatory disease of unknown origin, characterised by sensorineural hearing loss, episcleritis, and vasculitis. An autoimmune origin has been suggested but not proven. Our aim was to establish whether or not an autoimmune process is the cause of the disease.

METHODS

We used pooled IgG immunoglobulins derived from eight patients with Cogan's syndrome to screen a random peptide library to identify disease relevant autoantigen peptides. Among the identified peptides, one was recognised by all the patients' sera. Antibodies against peptides were affinity purified from patients' sera and used to characterise the autoantigen, to stain human cochlea, and to transfer the features of Cogan's disease into animals.

FINDINGS

We identified an immunodominant peptide that shows similarity with autoantigens such as SSA/Ro and with the reovirus III major core protein lambda 1. The peptide sequence shows similarity also with the cell-density enhanced protein tyrosine phosphatase-1 (DEP-1/CD148), which is expressed on the sensory epithelia of the inner ear and on endothelial cells. IgG antibodies against the peptide, purified from the patients' sera, recognised autoantigens and DEP-1/CD148 protein, bound human cochlea, and inhibited proliferation of cells expressing DEP-1/CD148. The same antibodies bound connexin 26, gene mutations of which lead to congenital inner-ear deafness. Furthermore, these antibodies were able to induce the features of Cogan's disease in mice.

INTERPRETATION

Our results indicate that Cogan's syndrome is an autoimmune disease, characterised by the presence of autoantibodies able to induce tissue damage on binding of cell-surface molecules present on the sensory epithelia of the inner ear and on endothelial cells.

ApoC-III gene polymorphisms and risk of coronary artery disease

Several polymorphisms in the apolipoprotein C-III (apoC-III) gene have been associated with hypertriglyceridemia, but the link with coronary artery disease risk is still controversial. In particular, apoC-III promoter sequence variants in the insulin responsive element (IRE), constitutively resistant to downregulation by insulin, have never been investigated in this connection. We studied a total of 800 patients, 549 of whom had angiographically documented coronary atherosclerosis, whereas 251 had normal coronary arteriograms. We measured plasma lipids, insulin, apoA-I, apoB, and apoC-III and assessed three polymorphisms in the apoC-III gene, namely, T-455C in the IRE promoter region, C1100T in exon 3, and Sst1 polymorphic site (S1/S2) in the 3' untranslated region. Each variant influenced triglyceride levels, but only the T-455C (in homozygosity) and S2 alleles influenced apoC-III levels. In coronary artery disease (CAD) patients, 18.6% were homozygous for the -455C variant compared with only 9.2% in CAD-free group (P < 0.001). In logistic regression models, homozygosity for -455C variant was associated with a significantly increased risk of CAD (OR = 2.5 and 2.18 for unadjusted and adjusted models, respectively) suggesting that it represents an independent genetic susceptibility factor for CAD.

The T cell receptor repertoire in psoriatic synovitis is restricted and T lymphocytes expressing the same TCR are present in joint and skin lesions

OBJECTIVE

To investigate the T cell receptor (TCR) repertoire in psoriatic synovitis and to determine whether T lymphocytes in joint and skin lesions show the same Vbeta CDR3 region.

METHODS

The expression of Valpha and Vbeta families was evaluated by reverse transcriptase-polymerase chain reaction. The CDR3 region of some Vbeta families was analyzed by cloning and sequencing.

RESULTS

We found a diverse variable beta chain usage within psoriatic synovial fluid of 11 patients although some Valpha and Vbeta families were more frequently expressed without evidence of clonality. Analysis of TCR in skin and synovial lesions of 3 patients showed identical CDR3 sequences, indicating that T cells bearing the same TCR are present at the 2 sites of chronic inflammation.

CONCLUSION

These data suggest that common or similar crossreactive antigens present in the 2 locations are responsible for the expansion of the same TCR-bearing T cells possibly already activated by a superantigen. This supports the hypothesis that both polyclonal and oligoclonal lymphocyte activation contribute to the initiation and persistence of psoriatic arthritis.

A1298C methylenetetrahydrofolate reductase mutation and coronary artery disease: relationships with C677T polymorphism and homocysteine/folate metabolism

5, 10-Methylenetetrahydrofolate reductase (MTHFR) is a crucial enzyme in homocysteine/methionine metabolism. The most-studied C677T polymorphism in the MTHFR gene results in a thermolabile variant with reduced activity, and is associated with increased levels of total plasma homocysteine, a risk factor for coronary artery disease. A new mutation in the MTHFR gene (A1298C) has also been reported to lower enzyme activity. Whether A1298C is a risk factor for coronary artery disease, separately or in combination with C677T, and/or relative to total plasma homocysteine and folate status, is unclear to date. We evaluated this hypothesis in 470 angiographically characterized subjects, 302 with coronary artery disease, and 168 with normal coronary arteries. The frequency of the 1298C allele was 0.33 and that of combined heterozygosity 0.315. No difference was found in the frequency of the genotypes or when analyzed for combined heterozygosity between patients with coronary artery disease and normals. Independent of folate status, the 1298C allele was not associated with increased total plasma homocysteine. No additional effect of A1298C on total plasma homocysteine was observed in 148 combined heterozygotes compared with 98 heterozygotes for the C677T alone. These findings do not support a major role for the A1298C mutation in homocysteine metabolism and emphasize the hypothesis that MTHFR genotypes may interfere with coronary artery disease risk only when an unbalanced nutritional status leads to raised total plasma homocysteine levels.

Clinical and pathologic findings in hemochromatosis type 3 due to a novel mutation in transferrin receptor 2 gene

BACKGROUND & AIMS

Although most patients with hereditary hemochromatosis are homozygous for a single mutation of the HFE gene on chromosome 6p, accumulating evidence indicates that the disease is genetically heterogeneous. Type 3 hemochromatosis, recently described in 4 families, is linked to mutations of the gene encoding transferrin receptor 2 on chromosome 7q22. Here we report data from a family carrying a new mutation of the transferrin receptor 2 gene.

METHODS

Detailed clinical and histopathologic documentation was available for most family members. The entire coding sequence and exon/intron boundaries of the transferrin receptor 2 gene were analyzed by direct sequencing.

RESULTS

A 12-nucleotide deletion in exon 16, causing the loss of 4 amino acids (AVAQ 594-597 del), was detected at the homozygous state in the 3 patients with histologically proven iron overload. The deletion segregated with the disease within the family and was not found in 100 healthy controls. Some clinical and pathologic characteristics, such as low penetrance in the premenopausal woman, and early iron deposition in periportal hepatocytes resembled those of classic, HFE-related hemochromatosis.

CONCLUSIONS

Our data support the role of the transferrin receptor 2 gene in hemochromatosis type 3 as well as its critical involvement in the maintenance of iron homeostasis in humans.

A common mutation in the 5,10-methylenetetrahydrofolate reductase gene affects genomic DNA methylation through an interaction with folate status

DNA methylation, an essential epigenetic feature of DNA that modulates gene expression and genomic integrity, is catalyzed by methyltransferases that use the universal methyl donor S-adenosyl-l-methionine. Methylenetetrahydrofolate reductase (MTHFR) catalyzes the synthesis of 5-methyltetrahydrofolate (5-methylTHF), the methyl donor for synthesis of methionine from homocysteine and precursor of S-adenosyl-l-methionine. In the present study we sought to determine the effect of folate status on genomic DNA methylation with an emphasis on the interaction with the common C677T mutation in the MTHFR gene. A liquid chromatography/MS method for the analysis of nucleotide bases was used to assess genomic DNA methylation in peripheral blood mononuclear cell DNA from 105 subjects homozygous for this mutation (T/T) and 187 homozygous for the wild-type (C/C) MTHFR genotype. The results show that genomic DNA methylation directly correlates with folate status and inversely with plasma homocysteine (tHcy) levels (P < 0.01). T/T genotypes had a diminished level of DNA methylation compared with those with the C/C wild-type (32.23 vs.62.24 ng 5-methylcytosine/microg DNA, P < 0.0001). When analyzed according to folate status, however, only the T/T subjects with low levels of folate accounted for the diminished DNA methylation (P < 0.0001). Moreover, in T/T subjects DNA methylation status correlated with the methylated proportion of red blood cell folate and was inversely related to the formylated proportion of red blood cell folates (P < 0.03) that is known to be solely represented in those individuals. These results indicate that the MTHFR C677T polymorphism influences DNA methylation status through an interaction with folate status.

Biochemical and genetic markers of iron status and the risk of coronary artery disease: an angiography-based study

BACKGROUND

Iron may promote coronary atherosclerotic disease (CAD) by increasing lipid peroxidation. Studies on biochemical or genetic markers of body iron stores as risk factors for CAD have yielded conflicting results.

METHODS

We studied 849 individuals with a clear-cut definition of the CAD phenotype, i.e., with (CAD; n = 546) or without (CAD-free; n = 303) angiographically documented disease. We determined serum ferritin, as a biochemical estimate of iron stores, and the C282Y mutation in the HFE gene, i.e., the main cause of hemochromatosis in Caucasians. The relationships of ferritin with serum markers of either inflammation [C-reactive protein (CRP)] or lipid peroxidation (malondialdehyde) were also investigated.

RESULTS

Mean ferritin concentrations were slightly higher in CAD vs CAD-free individuals, but this difference disappeared after adjusting for sex and CRP. Ferritin was significantly correlated with CRP (Spearman's test, rho = 0.129; P <0.001). Heterozygotes for Cys282Tyr were 4.8% among the CAD group and 6.6% among the CAD-free group (P = 0.26). The prevalence of high concentrations of stored iron, defined as ferritin concentrations above the sex-specific upper quintiles of the control distribution, was also similar in the two groups. There was a higher prevalence of "iron depletion" in CAD-free vs CAD females (20% vs 8.8%, respectively), but this difference disappeared after adjustment for age and other cardiovascular risk factors (odds ratio, 0.66; 95% confidence interval, 0.21-2.08). No differences in iron markers were found in CAD patients with or without myocardial infarction.

CONCLUSIONS

Our results do not support a role for biochemical or genetic markers of iron stores as predictors of the risk of CAD or its thrombotic complications.

Biochemical and Genetic Markers of Iron Status and the Risk of Coronary Artery Disease: An Angiography-based Study

Background: Iron may promote coronary atherosclerotic disease (CAD) by increasing lipid peroxidation. Studies on biochemical or genetic markers of body iron stores as risk factors for CAD have yielded conflicting results.

Methods: We studied 849 individuals with a clear-cut definition of the CAD phenotype, i.e., with (CAD; n = 546) or without (CAD-free; n = 303) angiographically documented disease. We determined serum ferritin, as a biochemical estimate of iron stores, and the C282Y mutation in the HFE gene, i.e., the main cause of hemochromatosis in Caucasians. The relationships of ferritin with serum markers of either inflammation [C-reactive protein (CRP)] or lipid peroxidation (malondialdehyde) were also investigated.

Results: Mean ferritin concentrations were slightly higher in CAD vs CAD-free individuals, but this difference disappeared after adjusting for sex and CRP. Ferritin was significantly correlated with CRP (Spearman’s test, ρ = 0.129; P &lt;0.001). Heterozygotes for Cys282Tyr were 4.8% among the CAD group and 6.6% among the CAD-free group (P = 0.26). The prevalence of high concentrations of stored iron, defined as ferritin concentrations above the sex-specific upper quintiles of the control distribution, was also similar in the two groups. There was a higher prevalence of “iron depletion” in CAD-free vs CAD females (20% vs 8.8%, respectively), but this difference disappeared after adjustment for age and other cardiovascular risk factors (odds ratio, 0.66; 95% confidence interval, 0.21–2.08). No differences in iron markers were found in CAD patients with or without myocardial infarction.

Conclusions: Our results do not support a role for biochemical or genetic markers of iron stores as predictors of the risk of CAD or its thrombotic complications.

Safety of rofecoxib in subjects with a history of adverse cutaneous reactions to aspirin and/or non-steroidal anti-inflammatory drugs

BACKGROUND

Adverse reactions to non-steroidal anti-inflammatory drugs (NSAID)s are frequent, and the need to identify a safe alternative drug is a common problem in clinical practice.

OBJECTIVE

To assess the tolerability of rofecoxib, a drug that specifically inhibits COX-2, in a group of NSAID-sensitive patients.

METHODS

One-hundred and four subjects (29 males and 75 females, mean age 35.6 +/- 14.1) were enrolled. All subjects had experienced one or more episode characterized by cutaneous symptoms (erythema, and/or urticaria angioedema) following the assumption of NSAIDs; 92 subjects experienced reactions to only one NSAID (single intolerance: SI) and 12 subjects had reactions to multiple NSAIDs (multiple intolerance: MI). Rofecoxib was challenged at the following dosages: 1/4 of 25 mg (6.25 mg), 1/4 of 25 mg, and 1/2 of 25 mg (12.5 mg), at intervals of 1 h if no symptoms had developed with the previous administration, in order to reach a cumulative dose of 25 mg. All subjects underwent two double-blind, placebo-controlled challenges in two consecutive days.

RESULTS

No reactions against placebo were observed. Similarly, no reactions were observed in all subjects both after the first and after the second challenge to rofecoxib.

CONCLUSIONS

The present study demonstrated that rofecoxib does not have cross-reactivity to NSAIDs. Rofecoxib is a safe alternative in subjects with previous adverse cutaneous reaction to NSAIDs.

Food allergy and seronegative arthritis: report of two cases

The link between food allergy and arthritis is still a matter for debate. Here we report two cases of patients suffering from arthritis sustained by food allergy. Diagnosis was performed on the basis of a 2-week elimination diet followed by an open and double-blind challenge test which was repeated three times. Both patients had a previous medical history of food allergy/intolerance. As the number of patients with joint complaints sustained by food allergy is very small it makes no sense to put all patients on diet. A previous medical history of food intolerance is one of the main reasons to start the long and difficult path towards a diagnosis of food allergy.

Different impact of deletion polymorphism of gene on the risk of renal and coronary artery disease

OBJECTIVE

An increased frequency of the angiotensin converting enzyme (ACE) D variant has recently been reported in patients with atheromatous renal artery disease (RAD), whereas controversy exists on the risk of coronary artery disease (CAD) associated with this polymorphism. In spite of the frequent coexistence of RAD and CAD, no studies have specifically compared ACE insertion/deletion (I/D) polymorphism in patients with coronary versus renal artery disease or defined the risk of each disease associated with the D variant.

DESIGN

We designed a large case-control study of subjects for whom objective renal or coronary angiographic documentation was available.

METHODS AND RESULTS

We analysed ACE I/D genotype and clinical-biochemical data of a total of 942 subjects (123 patients with and 137 without angiographic evidence of RAD, 420 patients with and 262 without angiographic evidence of CAD). Renal (with and without RAD) and coronary patients were similar for most conventional risk factors. There was no difference in DD frequency between CAD and CAD-free patients (38.1 versus 33.6%, NS) and DD homozygosity was not associated with CAD risk (OR = 1.27, 95% CI = 0.82-1.98). In contrast, the DD genotype was more frequent in RAD than in RAD-free patients (54.5 versus 39.4, P < 0.05) and was associated with a 2.25-fold increased risk of RAD in both the univariate and multivariate logistic regression models. Additional predictors of RAD were age and creatinine. In RAD/RAD-free patients with angiographically documented CAD, DD homozygosity was confirmed to be preferentially associated with RAD (P < 0.05).

CONCLUSIONS

ACE D variant is preferentially associated with atherosclerotic renal rather than with coronary disease, despite similar exposure to atherogenic noxae. DD homozygosity confers a 2.25-fold increased risk of RAD.