Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P30044 (antioxidant enzyme)
 8,037 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Mycobacterium tuberculosis (H37Rv), the causative agent of the dreaded disease tuberculosis, contains three thioredoxins and a single thioredoxin reductase. Thioredoxin reductase is a member of the pyridine-nucleotide disulfide oxidoreductase family of flavoenzymes. The thioredoxin reductase gene with a His tag at the C-terminus was expressed in Escherichia coli and purified. The dimeric (70 kDa) protein was incubated with 10 mM DTT for 30 min and then crystallized using the hanging-drop vapour-diffusion method in the presence of 15% PEG 3350 and phosphate-citrate buffer pH 5 at room temperature (298 K). A diffraction data set complete to 3 A resolution has been collected under cryoconditions and the space group was determined to be P4(1)2(1)2, with unit-cell parameters a = 107.4, c = 118.2 A. Matthews coefficient calculations revealed the presence of two monomers in the asymmetric unit.
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PMID:Expression, purification, crystallization and preliminary X-ray crystallographic studies of Mycobacterium tuberculosis thioredoxin reductase. 1503 84

Antituberculosis drug (ATD)-induced hepatotoxicity is a major impediment for the effective treatment of tuberculosis (TB). All first-line anti-TB medications have adverse effects that interrupt the successful completion of TB treatment. This investigation focuses on the evaluation of the protective role of Nigella sativa (NS) against liver injury caused by ATDs. Female rats were treated with ATDs for 8 weeks (3 d/wk) followed by NS for 8 weeks (3 d/wk). The antioxidant activity of NS was estimated with a 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay and by analyzing total phenolic contents. Qualitative characterization of active compounds of the plant was done by high-performance liquid chromotography (HPLC). ATD-induced adverse effects were associated with sharp elevation in levels of serum transaminases, albumin, cholesterol, urea, uric acid, creatinine, and blood urea nitrogen (BUN). ATDs significantly increased lipid peroxidation (LPO) and decreased enzyme activities (superoxide dismutase [SOD], catalase [CAT], adenosine triphosphatase [ATPase], and glucose-6-phosphatase [G6Pase]) in liver, indicating oxidative stress. Conjoint treatment with NS could reverse the serological biochemistry and inhibit oxidative stress by suppressing LPO and augmenting antioxidant enzyme activity toward that of the control. Histological studies support the above biochemical findings. Results indicate that NS exerts excellent hepatoprotective abilities and can be used as a supplement to improve patient adherence and reduce interruptions in treatment due to ATD-related liver injury.
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PMID:Therapeutic Efficacy of Nigella Sativa Linn. against Antituberculosis Drug-Induced Hepatic Injury in Wistar Rats. 2727 84

Heme oxygenase-1 (HO-1) is a stress response antioxidant enzyme which catalyzes the degradation of heme released during inflammation. HO-1 expression is upregulated in both experimental and human Mycobacterium tuberculosis infection, and in patients it is a biomarker of active disease. Whether the enzyme plays a protective versus pathogenic role in tuberculosis has been the subject of debate. To address this controversy, we administered tin protoporphyrin IX (SnPPIX), a well-characterized HO-1 enzymatic inhibitor, to mice during acute M. tuberculosis infection. These SnPPIX-treated animals displayed a substantial reduction in pulmonary bacterial loads comparable to that achieved following conventional antibiotic therapy. Moreover, when administered adjunctively with antimycobacterial drugs, the HO-1 inhibitor markedly enhanced and accelerated pathogen clearance. Interestingly, both the pulmonary induction of HO-1 expression and the efficacy of SnPPIX treatment in reducing bacterial burden were dependent on the presence of host T lymphocytes. Although M. tuberculosis expresses its own heme-degrading enzyme, SnPPIX failed to inhibit its enzymatic activity or significantly restrict bacterial growth in liquid culture. Together, the above findings reveal mammalian HO-1 as a potential target for host-directed monotherapy and adjunctive therapy of tuberculosis and identify the immune response as a critical regulator of this function.
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PMID:Pharmacological Inhibition of Host Heme Oxygenase-1 Suppresses Mycobacterium tuberculosis Infection In Vivo by a Mechanism Dependent on T Lymphocytes. 2779

The antioxidant enzyme heme oxygenase-1 (HO-1) is implicated in the pathogenesis of tuberculosis (TB) and has been proposed as a biomarker of active disease. Nevertheless, the mechanisms by which Mycobacterium tuberculosis (Mtb) induces HO-1 as well as how its expression is affected by HIV-1 coinfection and successful antitubercular therapy (ATT) are poorly understood. We found that HO-1 expression is markedly increased in rabbits, mice, and non-human primates during experimental Mtb infection and gradually decreased during ATT. In addition, we examined circulating concentrations of HO-1 in a cohort of 130 HIV-1 coinfected and uninfected pulmonary TB patients undergoing ATT to investigate changes in expression of this biomarker in relation to HIV-1 status, radiological disease severity, and treatment outcome. We found that plasma levels of HO-1 were elevated in untreated HIV-1 coinfected TB patients and correlated positively with HIV-1 viral load and negatively with CD4+ T cell count. In both HIV-1 coinfected and Mtb monoinfected patients, HO-1 levels were substantially reduced during successful TB treatment but not in those who experienced treatment failure or subsequently relapsed. To further delineate the molecular mechanisms involved in induction of HO-1 by Mtb, we performed a series of in vitro experiments using mouse and human macrophages. We found that Mtb-induced HO-1 expression requires NADPH oxidase-dependent reactive oxygen species production induced by the early-secreted antigen ESAT-6, which in turn triggers nuclear translocation of the transcription factor NRF-2. These observations provide further insight into the utility of HO-1 as a biomarker of both disease and successful therapy in TB monoinfected and HIV-TB coinfected patients and reveal a previously undocumented pathway linking expression of the enzyme with oxidative stress.
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PMID:Mycobacterium tuberculosis Induction of Heme Oxygenase-1 Expression Is Dependent on Oxidative Stress and Reflects Treatment Outcomes. 2855 88