Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P02794 (ferritin)
 17,525 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Drugs are optimally effective in the therapeutic concentration range. A challenge in the delivery area is to design a system that will allow the therapeutic range to be accessed and to be maintained for defined periods. The lipidic cubic phases have been used as delivery matrices with such properties. For water-soluble drugs, release from the cubic phase is controlled by transport through aqueous channels that permeate the phase. Channel size can be tuned over wide limits by adjusting temperature and lipid identity. Thus, the possibility exists to regulate the rate of drug release from the cubic phase. With a view to exploiting these features for small molecule, proteinaceous and nucleic acid drugs, we have taken a systematic approach toward understanding how cubic phase transport is controlled by phase identity and microstructure and by the physical and chemical properties of the drug itself. Measurements were made using tryptophan, rubipy, DNA and six proteins as drug surrogates and with three hosting lipids. Remarkably, transport was observed with apo-ferritin whose size far exceeds that of the aqueous channel suggesting a molecular breathing or peristalsis type of facilitated release. Exquisite control over release was achieved by adjusting electrostatic interaction strength and by His-tag displacement.
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PMID:Controlling release from the lipidic cubic phase. Amino acids, peptides, proteins and nucleic acids. 1599 Jan 92

The effects of body iron stores on diquat (DQ)-induced toxicity were examined in male Fischer-344 rats, which are sensitive to this herbicide. The rats (5 weeks old) were fed diets containing 40 (lower iron storage [LIS] group) or 320 ppm iron (higher iron storage [HIS] group) for 5 weeks. The concentrations of nonheme iron and ferritin in the liver and kidney were significantly higher in the HIS group than in the LIS group (P<0.0001), although there was no significant differences between the HIS and LIS groups in hematological parameters, including red blood cell count, hemoglobin concentration, and mean corpuscular volume. Three hours after administration of 0.1 mmol DQ/kg, serum alanine aminotransferase and urea nitrogen were significantly higher than in controls (saline injection) for both the LIS and HIS groups (P<0.01), and, after DQ injection, these parameters were significantly higher in the HIS group than in the LIS group (P<0.01). When the rats were injected with 0.075 or 0.1 mmol DQ/kg, the survival time was significantly shorter in the HIS group than in the LIS group (P<0.05). These findings suggest that higher body iron stores result in more severe DQ toxicity in Fischer-344 rats.
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PMID:Relationship between body iron stores and diquat toxicity in male Fischer-344 rats. 1667 Sep 37

A couple was investigated for subfertility. Haemochromatosis was suspected when the 36-year-old man had failure of ejaculation, fatigue and limited facial hair growth. Haemochromatosis was confirmed by an iron saturation of 102% (normal range: 20-45), a highly elevated serum ferritin concentration of 5468 mg/1l (normal range: 18-280) and highly elevated liver enzymes. Molecular genetics showed homozygous C282Y mutation of the HFE gene. Due to consequent venesection therapy, levels of ferritin and transferrin decreased and liver enzymes normalized. However luteinizing hormone and follicle stimulating hormone failed to increase to normal levels. Treatment with gonadotropins was then applied, which corrected ejaculation and semen characteristics. His partner failed to become pregnant with ovulation stimulation and intrauterine inseminations. After two unsuccessful IVF procedures she became pregnant in the third procedure. Haemochromatosis should be considered and iron studies performed if subfertility due to an endocrine disorder is being investigated. Deposition in the pituitary or the gonads of the HFE-mutated patients leads to hypogonadism. Most of the patients with C282Y mutation are homozygous (85-90%), but the majority of the carriers will not develop the disease. Deficiency of hepcidin, an important regulator for the iron metabolism, was suspected in our patient, based on the early onset of his disease and the low serum levels of hepcidin. The age at diagnosis and the start of venesections is critical for reversal of organ damage. Aggressive venesection can restore hypothalamic-pituitary-gonadal function, preventing further organ damage. But with increasing disease progression venesection will not restore azoospermia or the failure to ejaculate.
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PMID:[Anejaculation caused by haemosiderosis: male infertility in hereditary haemochromatosis]. 1763 84

Hereditary hemochromatosis (HH) is very rare in Asia. Here, we describe a Taiwanese woman presenting with fully developed characteristics of HH including bronze skin, DM, decreased MRI T2 signal intensity over liver and pituitary gland. Biochemistry of iron profile indicated a severe status of iron overload by serum iron: 194 microg/dL, serum ferritin: 6640 microg/L, transferrin saturation: 92.8%. By measuring the hepatic iron index 8.48 (>1.9) of her liver biopsy tissue, the diagnosis of HH was established. Diagnosis of non-HFE HH was carried out since the whole HFE genome was sequenced but failed to localize any genetic alterations. The whole genome of transferrin receptor 2 (TfR2) was sequenced and a novel mutation of 13528 G-->A (Arg 481 His) in exon 11 was detected. Therefore, type 3 hemochromatosis was confirmed. The distinct clinical features, extremely high iron index and impressive iron staining in her liver biopsy tissue may represent an aggravated iron deposition in the liver caused by this novel mutation. Our finding implicates functional importance of histidine in exchange of arginine at amino acid 481 of transferrin receptor 2 in iron homeostasis. This case reminds physicians in Asia to keep in mind that hemochromatosis could be a rare cause of DM.
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PMID:A novel mutation of transferrin receptor 2 in a Taiwanese woman with type 3 hemochromatosis. 1756 47

Abundance values obtained from direct LC-MS analyses were used to compare the proteomes of six transposon-insertion mutants of Desulfovibrio desulfuricans G20, the lab strain (G20lab) and a sediment-adapted strain (G20sediment). Three mutations were in signal transduction histidine kinases, and three mutations were in other regulatory proteins. The high-throughput accurate mass and time (AMT) tag proteomic approach was utilized to analyze the proteomes. A total of 1318 proteins was identified with high confidence, approximately 35% of all predicted proteins in the D. desulfuricans G20 genome. Proteins from all functional categories were identified. Significant differences in the abundance of 30 proteins were detected between the G20lab strain and the G20sediment strain. Abundances of proteins for energy metabolism, ribosomal synthesis, membrane biosynthesis, transport, and flagellar synthesis were affected in the mutants. Specific examples of proteins down-regulated in mutants include a putative tungstate transport system substrate-binding protein and several proteins related to energy production, for example, 2-oxoacid:acceptor oxidoreductase, cytochrome c-553, and formate acetyltransferase. In addition, several signal transduction mechanism proteins were regulated in one mutant, and the abundances of ferritin and hybrid cluster protein were reduced in another mutant. However, the similar abundance of universal stress proteins, heat shock proteins, and chemotaxis proteins in the mutants revealed that regulation of chemotactic behavior and stress regulation might not be observed under our growth conditions. This study provides the first proteomic overview of several sediment fitness mutants of G20, and evidence for the difference between lab strains and sediment-adapted strains at the protein level.
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PMID:Proteome analysis of Desulfovibrio desulfuricans G20 mutants using the accurate mass and time (AMT) tag approach. 1760 84

We report the case of a 54-year-old patient presenting with a typical pernicious anaemia. His mother was diagnosed with unquestionable pernicious anaemia 5 years previously. Serum ferritin was strongly increased (1,160 microg/l, normal range 29-380), with a transferrin saturation of 95%. We found a homozygous C282Y mutation of the HFE gene in our patient, his mother being heterozygous. The son of our patient was compound C282Y/H63D heterozygous without detectable pernicious anaemia. This seems to be the first report of an association between familial pernicious anaemia and hereditary haemochromatosis. The simultaneous occurrence of the 2 diseases in the same patient helps to delineate the relative contribution of each of them to iron metabolism and erythropoiesis: iron overload was only moderately increased and responded rapidly to phlebotomies, whereas haemochromatosis did not modify the cytologic presentation of pernicious anaemia.
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PMID:Association of familial pernicious anaemia and hereditary haemochromatosis. 1817 74

A 28-year was admitted with heart failure. His medical history included treatment for hypogonadotropic hypogonadism. Echocardiography showed dilatation of all chambers. Elevated serum ferritin levels and liver biopsy indicated hereditary hemochromatosis. Cardiac iron overload was seen on magnetic resonance imaging. Genetic testing revealed homozygosis for G320 V mutation, confirming the diagnosis of juvenile hemochromatosis. Phlebotomy on a biweekly regimen was started and after twelve months of therapy the patient had normal ferritin values as well as normal ejection fraction on echocardiography.
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PMID:[28-year old patient with successfully treated dilatative cardiomyopathy]. 1821 19

Iron is an essential metal for all living organisms. However, iron homeostasis needs to be tightly controlled since iron can mediate the production of reactive oxygen species, which can damage cell components and compromise the integrity and/or cause DNA mutations, ultimately leading to cancer. In eukaryotes, iron-regulatory protein 1 (IRP1) plays a central role in the control of intracellular iron homeostasis. This occurs by interaction of IRP1 with iron-responsive element regions at 5' of ferritin mRNA and 3' of transferrin mRNA which, respectively, represses translation and increases mRNA stability. We have expressed IRP1 using the plasmid pT7-His-hIRP1, which codifies for human IRP1 attached to an NH2-terminal 6-His tag. IRP1 was expressed in Escherichia coli using the strategy of co-expressing chaperonins GroES and GroEL, in order to circumvent inclusion body formation and increase the yield of soluble protein. The protein co-expressed with these chaperonins was obtained mostly in the soluble form, which greatly increased the efficiency of protein purification. Metal affinity and FPLC ion exchange chromatography were used in order to obtain highly purified IRP1. Purified protein was biologically active, as assessed by electrophoretic mobility shift assay, and could be converted to the cytoplasmic aconitase form. These results corroborate previous studies, which suggest the use of folding catalysts as a powerful strategy to increase protein solubility when expressing heterologous proteins in E. coli.
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PMID:Increased expression and purification of soluble iron-regulatory protein 1 from Escherichia coli co-expressing chaperonins GroES and GroEL. 1829 88

Soybean seed ferritin is essential for human iron supplementation and iron deficiency anemia prevention because it contains abundant bioavailable iron and is frequently consumed in the human diet. However, it is poorly understood in regards its several properties, such as iron mineralization, subunit assembly, and protein folding. To address these issues, we decided to prepare the soybean seed ferritin complex via a recombinant DNA approach. In this paper, we report a rapid and simple Escherichia coli expression system to produce the soybean seed ferritin complex. In this system, two subunits of soybean seed ferritin, H-2 and H-1, were encoded in a single plasmid, and optimal expression was achieved by additionally coexpressing a team of molecular chaperones, trigger factor and GroEL-GroES. The His-tagged ferritin complex was purified by Ni2+ affinity chromatography, and an intact ferritin complex was obtained following His-tagged enterokinase (His-EK) digestion. The purified ferritin complex synthesized in E. coli demonstrated some reported features of its native counterpart from soybean seed, including an apparent molecular weight, multimeric assembly, and iron uptake activity. We believe that the strategy described in this paper may be of general utility in producing other recombinant plant ferritins built up from two types of subunits.
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PMID:Expression and purification of intact and functional soybean (Glycine max) seed ferritin complex in Escherichia coli. 1830 75

An African American male of West Indies descent was diagnosed to have elevated transferrin saturation, hyperferritinemia, severe iron deposition in hepatocytes, and hepatic cirrhosis at age 4. He was treated with serial phlebotomy to maintain a normal serum ferritin concentration thereafter. We evaluated him at age 23 and confirmed that he had normal serum ferritin levels, severe iron deposition in hepatocytes, hepatic cirrhosis, and portal hypertension. He did not have endocrinopathy, cardiomyopathy, or arthropathy. He was homozygous for the novel hemojuvelin (HJV) premature stop-codon mutation R54X (exon 3; c.160A-->T). He did not have either HFE C282Y, H63D, or S65C, or deleterious coding region mutations of SLC40A1, TFR2, or HAMP. His erythrocyte measures and hemoglobin electrophoresis were consistent with alpha-thalassemia trait. We conclude that homozygosity for HJV R54X accounts for his severe, early age-of-onset hemochromatosis; his phenotype was probably modified by serial phlebotomy therapy.
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PMID:Early age-of-onset iron overload and homozygosity for the novel hemojuvelin mutation HJV R54X (exon 3; c.160A-->T) in an African American male of West Indies descent. 1849 90


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