Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0409974 (lupus)
 22,386 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Patients with drug-related lupus erythematosus produce antibodies to nuclear histones which can be detected by a three-step indirect immunofluorescence technique. Procainamide-related antinuclear antibodies were detected by this technique, but hydralazine-related antinuclear antibodies were not. Certain evidence suggests that antibodies induced by the two drugs are reactive with different subclasses of histones. Hydralazine was shown to interact with a soluble DNA-histone complex, and the resulting interaction rendered the histone moiety resistant to trypsin digestion. This mechanism may help to maintain DNA-histone complexes in a potentially immunogenic form and result in the production of autoantibodies.
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PMID:The role of histones as nuclear autoantigens in drug-related lupus erythematosus. 702 42

A 58 year old woman developed systemic symptoms, interstitial lung disease, splenomegaly, leukopenia and anti-histone and anti-nuclear antibodies (ANA), while treated with hydralazine for hypertension. Five months after presentation she was admitted with high fever, skin rash and atypical lymphocytosis due to acute cytomegalovirus (CMV) infection. Worsening leukopenia and increased ANA were found, and high titres of anti-DNA antibodies, anti-cardiolipin antibodies and rheumatoid factors appeared. Hydralazine was stopped and the patient gradually became asymptomatic. All autoantibodies spontaneously disappeared (over 16 weeks), and the white cell count and spleen size became normal. The patient was found to be a slow acetylator and to have both HLA-DR4 and selective IgA deficiency. Thus, a multifactorial genetic susceptibility to develop drug-induced lupus was brought out in stages first by hydralazine and then by CMV, yet all manifestations and autoantibodies resolved spontaneously, demonstrating the complex interplay of varied environmental factors with a genetic predisposition in the pathogenesis of autoimmunity.
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PMID:Effect of acute cytomegalovirus infection on drug-induced SLE. 783 Nov 73

Autoantibodies directed against myeloperoxidase and elastase have been found in patients developing hydralazine-induced lupus and hydralazine-induced isolated glomerulonephritis. The aim of this study was to investigate influence of hydralazine and dihydralazine upon myeloperoxidase and elastase enzyme activity. Using a 4-aminoantipyrin in vitro system, dihydralazine was 2.5 times as potent in inhibiting myeloperoxidase activity as compared to hydralazine. The corresponding Ki-values were 4 microns M for dihydralazine and 25 microM for hydralazine. When using 2.2'-azino-bis-3-ethyl-benzothiazoline-6-sulphonic acid system inhibition was found at lower concentrations. Furthermore, the difference between the compounds was not so pronounced as seen for 4-aminoantipyrin. The Ki-values for hydralazine and dihydralazine were 1.2 and 1.4 microM respectively. Complete inhibition was seen for both compounds at concentrations above 7.5 microM. Hydralazine binds to elastase, but neither hydralazine nor dihydralazine inhibited elastase enzyme activity.
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PMID:Interaction of myeloperoxidase and elastase enzyme activity with the antihypertensive agents hydralazine and dihydralazine. 824 10

The use of the antihypertensive hydralazine is associated with an autoimmune syndrome resembling systemic lupus erythematosus. Adverse drug reactions, such as drug-induced lupus, often involve reactive intermediates. Oxidation of hydralazine by liver microsomes or activated leukocytes leads to reactive intermediates that covalently bind to protein and may be involved in hydralazine-induced lupus. Oxidation of hydralazine to a reactive intermediate by cells involved in immune response, such as leukocytes, would be more likely to lead to an autoimmune reaction, such as drug-induced lupus, than would oxidation by cells in the liver. Leukocytes possess a defense system that generates HOCl in response to invading microorganisms. Hydralazine was oxidized to a reactive intermediate by HOCl generated by activated leukocytes. The reactive intermediate was trapped with N-acetylcysteine and the adduct was identified as 1-phthalazylmercapturic acid. The reactive intermediate is likely the diazonium salt of hydralazine. Two stable products were formed in the reaction, phthalazine and phthalazinone. Although phthalazine is oxidized to phthalazinone by HOCl, the rate of the reaction is much too slow to explain the rapid production of phthalazinone. It is more likely that most of the phthalazinone is formed by reaction of the putative diazonium salt with water. We propose that this reactive metabolite is responsible for hydralazine-induced lupus.
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PMID:Reactive intermediates in the oxidation of hydralazine by HOCl: the major oxidant generated by neutrophils. 826 46

The anti-hypertensive agent hydralazine can cause a lupus-like syndrome characterized by serosal inflammation, arthralgias and rashes. The kidneys however are usually spared. The condition is characterized by circulating immune complexes and antinuclear antibodies, whilst antibodies against double-stranded DNA are rare. Hydralazine can also cause a systemic vasculitis with a pauci-immune rapidly progressive glomerulonephritis, which is associated with autoantibodies directed against components of the neutrophil cytoplasm. In this study, ten patients with hydralazine-induced vasculitis had antibodies with specificities for both myeloperoxidase and lactoferrin. We suggest that this particular pattern of autoantibodies, together with antibodies with reactivity against nuclear components including double-stranded DNA, are characteristic findings in hydralazine-induced vasculitis. In addition, renal involvement appears to be more common in this group of patients with vasculitis than in those with the lupus-like syndrome.
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PMID:Antigen specificity in hydralazine associated ANCA positive systemic vasculitis. 854 62

Systemic lupus erythematosus (SLE) is a multi-system autoimmune disorder that can affect the upper airway. Hydralazine has been known to cause a lupus-like syndrome that can produce the clinical manifestations of SLE. We discuss a case of hydralazine-induced lupus, presenting with acute laryngeal oedema and right vocal fold paralysis. Cessation of hydralazine therapy resulted in reversal of paralysis.
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PMID:Hydralazine-induced lupus and vocal fold paralysis. 987 82

Hydralazine was one of the first orally active antihypertensive drugs developed. Currently, it is used principally to treat pregnancy-associated hypertension. Hydralazine causes two types of side effects. The first type is an extension of the pharmacologic effect of the drug and includes headache, nausea, flushing, hypotension, palpitation, tachycardia, dizziness, and salt retention. The second type of side effects is caused by immunologic reactions, of which the drug-induced lupus-like syndrome is the most common, and provides clues to underscoring hydralazine's DNA demethylating property in connection with studies demonstrating the participation of DNA methylation disorders in immune diseases. Abnormalities in DNA methylation have long been associated with cancer. Despite the fact that malignant tumors show global DNA hypomethylation, regional hypermethylation as a means to silence tumor suppressor gene expression has attracted the greatest attention. Reversibility of methylation-induced gene silencing by pharmacologic means, which in turns leads to antitumor effects in experimental and clinical scenarios, has directed efforts toward developing clinically useful demethylating agents. Among these, the most widely used comprise the nucleosides 5-azacytidine and 2'deoxy-5-azacytidine; however, these agents, like current cytotoxic chemotherapy, causes myelosuppression among other side effects that could limit exploitation of their demethylating properties. Among non-nucleoside DNA demethylating drugs currently under development, the oral drug hydralazine possess the ability to reactivate tumor suppressor gene expression, which is silenced by promoter hypermethylation in vitro and in vivo. Decades of extensive hydralazine use for hypertensive disorders that demonstrated hydralazine's clinical safety and tolerability supported its testing in a phase I trial in patients with cancer, confirming its DNA demethylating activity. Hydralazine is currently being evaluated, along with histone deacetylase inhibitors either alone or as adjuncts to chemotherapy and radiation, for hematologic and solid tumors in phase II studies.
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PMID:Hydralazine target: from blood vessels to the epigenome. 1650

We report two cases of hydralazine-induced vasculitis with rare complications: pulmonary renal syndrome and digital gangrene. We also review 68 published cases of hydralazine-induced vasculitis. Hydralazine-induced vasculitis mimics idiopathic antineutrophil cytoplasmic antibody (ANCA)-positive vasculitis. However, it also produces other autoantibodies, such as antinuclear antibodies, antihistone antibodies, anti-dsDNA antibodies, and antiphospholipid antibodies. Patients with hydralazine-induced vasculitis typically have a more severe course than those with hydralazine-induced lupus, predominantly due to renal vasculitis, and require a more aggressive treatment.
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PMID:Hydralazine-induced autoimmune disease: comparison to idiopathic lupus and ANCA-positive vasculitis. 1942 72

Idiosyncratic drug reactions (IDRs) represent a major clinical problem, and at present, the mechanisms involved are still poorly understood. One animal model that we have used for mechanistic studies of IDRs is penicillamine-induced autoimmunity in Brown Norway (BN) rats. Previous work in our lab found that macrophage activation preceded the clinical autoimmune syndrome. It is thought that one of the interactions between T cells and macrophages involves reversible Schiff base formation between an amine on T cells and an aldehyde on macrophages, but the identity of the molecules involved is unknown. It is also known that penicillamine reacts with aldehyde groups to form a thiazolidine ring, which unlike a Schiff base, is essentially irreversible. Such binding could lead to macrophage activation. Generalized macrophage activation could lead to the observed autoimmune reaction. Hydralazine and isoniazid also react with aldehydes to form stable hydrazones, and they also cause an autoimmune lupus-like syndrome. In this study, isolated spleen cells from male BN rats were incubated with biotin-aldehyde-reactive probe (ARP, a hydroxylamine), biotin-hydrazide, or D-penicillamine. At all concentrations, ARP, hydrazide, and penicillamine preferentially "stained" macrophages relative to other spleen cells. In addition, preincubation of cells with penicillamine or hydralazine decreased ARP staining of macrophages, which further indicates that most of the ARP binding to macrophages involves binding to aldehyde groups. This provides support for the hypothesis that the interaction between aldehyde-containing signaling molecules on macrophages and penicillamine could be the initial event of penicillamine-induced autoimmunity. Several of the proteins to which ARP binds were identified, and some such as myosin are attractive candidates to mediate macrophage activation.
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PMID:Covalent binding of penicillamine to macrophages: implications for penicillamine-induced autoimmunity. 1946 40

Idiosyncratic drug reactions represent a serious health problem, and they remain unpredictable largely due to our limited understanding of the mechanisms involved. Penicillamine-induced autoimmunity in Brown Norway (BN) rats represents one model of an idiosyncratic reaction, and this drug can also cause autoimmune reactions in humans. We previously demonstrated that penicillamine binds to aldehydes on the surface of macrophages. There is evidence that an imine bond formed by aldehyde groups on macrophages and amine groups on T cells is one type of interaction between these two cells that is involved in the induction of an immune response. We proposed that the binding of penicillamine with aldehyde groups on macrophages could lead to their activation and in some patients could lead to autoimmunity. In this study, the transcriptome profile of spleen macrophages 6 h after penicillamine treatment was used to detect effects of penicillamine on macrophages with a focus on 20 genes known to be macrophage activation biomarkers. One biological consequence of macrophage activation was investigated by determining mRNA levels for IL-15 and IL-1 beta which are crucial for NK cell activation, as well as levels of mRNA for selected cytokines in spleen NK cells. Up-regulation of the macrophage activating cytokines, IFN-gamma and GM-CSF, and down-regulation of IL-13 indicated activation of NK cells, which suggests a positive feedback loop between macrophages and NK cells. Furthermore, treatment of a murine macrophage cell line, RAW264.7, with penicillamine increased the production of TNF-alpha, IL-6, and IL-23, providing additional evidence that penicillamine activates macrophages. Hydralazine and isoniazid cause a lupus-like syndrome in humans and also bind to aldehyde groups. These drugs were also found to activate RAW264.7 macrophages. Together, these data support the hypothesis that drugs that bind irreversibly with aldehydes lead to macrophage activation, which in some patients can lead to an autoimmune syndrome.
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PMID:D-penicillamine-induced autoimmunity: relationship to macrophage activation. 1957 32


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