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)

Polycythemia in CAPD patients has been rarely described. Over an eight year period, 4 out of 123 CAPD patients (3%) were identified as having Hct values exceeding 50% for 1 month or longer. All of the 4 patients were insulin dependent diabetics (4/47 diabetic patients, 8.5%). Charts were reviewed on 3 of these 4 patients. Polycythemia developed after a mean of 21 +/- 7 months on peritoneal dialysis. Prior to the development of polycythemia, ferritin levels were low and ferrous sulfate therapy was begun at a time the Hct values were 36 to 40%. Erythropoietin levels were obtained in 2 patients, and were 22 U/L (Hct 51%) and less than 5 U/L (Hct 55%). Renal ultrasound failed to show renal masses or cysts. One patient had a plasma volume of 2.1 L (normal 2.4-3.2 L); another patient was clinically volume depleted. Complications during the period of polycythemia included gangrenous feet requiring amputation in 2 patients, CVA in 2 patients, and splenic infarct in 1 patient. One patient died of cerebral thrombosis. We conclude that polycythemia is uncommon in CAPD patients and occurs most often in diabetic patients. Volume depletion and iron therapy may play a role in its etiology. In this high risk group of patients polycythemia may contribute to vascular complications and should be avoided.
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PMID:Polycythemia in diabetic patients on CAPD. 168 Apr 62

Stimulation of the immune system results in a series of metabolic changes that are antagonistic toward growth. Monokines, including interleukin-1, tumor necrosis factor, and interleukin-6, are released from cells of the monocyte-macrophage lineage after recognition of immunogens. They appear to mediate homeorhetic response, which alters the partitioning of dietary nutrients away from growth and skeletal muscle accretion in favor of metabolic processes which support the immune response and disease resistance. These alterations include 1) decreased skeletal muscle accretion due to increased rates of protein degradation and decreased protein synthesis; 2) increased basal metabolic rate resulting in increased energy utilization; 3) use of dietary amino acids for gluconeogenesis and as an energy source instead of for muscle protein accretion; 4) synthesis by the liver of acute phase proteins; 5) redistribution of iron, zinc, and copper within the body due to the hepatic synthesis of metallothionein, ferritin, and ceruloplasmin; (6) impaired accretion of cartilage and bone; and 7) release of hormones such as insulin, glucagon, and corticosterone. These monokines also influence the differentiation of cells. Tumor necrosis factor suppresses the differentiation of myoblasts and adipocytes whereas the chicken monokine myelomonocytic growth factor induces the differentiation of granulocytes.
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PMID:Monokines in growth and development. 171 68

Iron overload was produced in Wistar rats by repeated intraperitoneal injections of ferric nitrilotriacetate (Fe(3+)-NTA) for one to six months. Pancreatic tissues from these iron-overloaded rats and untreated controls were examined for insulin (for B cells), glucagon (for A cells), transferrin receptor (TfR), transferrin (Tf) and ferritin (Ft) using immunohistochemical methods, and for iron by histochemical Berlin blue staining. In the islets of iron-overloaded rats, increased Ft staining appeared prior to deposition of Berlin blue-stainable iron, and the staining intensity of Ft and iron was stronger in B cells than in A cells. In the islets of untreated control rats, the staining intensity of TfR was stronger in B cells than in A cells. TfR staining of the islets was weaker in iron-overloaded rats than in the controls. These findings suggest that 1) iron uptake by islet cells in vivo is regulated and mediated by TfR, 2) intracytoplasmic Ft transforms into stainable iron in iron-overloaded rats, and 3) predominance of TfR expression in B cells may result in selective deposition of iron and predispose B cells to damage and diabetes mellitus in iron-overloaded rats.
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PMID:Transferrin receptors and selective iron deposition in pancreatic B cells of iron-overloaded rats. 177 64

Dynamic laser light scattering studies on the heat aggregation behavior of phycobilisomes (PBS), ferritin, insulin, and immunoglobulin (IgG) in dilute aqueous solutions has been reported. Except for PBS, results are reported for heat aggregation trends in these proteins for three different pH environments (4.0, 7.5, 9.1). For PBS, studies were performed only in the neutral buffer medium (pH 7.5). The experiments were performed in the very dilute concentration regime (between 0.23 and 1.8 gL-1). For all these samples heat aggregation and dissociation trends were found to be linear with temperature. Upon temperature reversal (self-cooling), hysteresis-like behavior observed in insulin was found to be predominantly large at pH 7.5. PBS, ferritin, and IgG showed no such behavior at any of three pH values, and retraced their path of aggregation while dissociating on temperature reversal. Heat aggregation and dissociation processes in ferritin were found to be independent of pH. The IgG samples showed smooth aggregation tendency only up to 35 degrees C in the buffer media pH 4.0 and 9.1, whereas for pH 7.0 the same could be observed until 60 degrees C. Low polydispersity in the correlation spectra was observed in case of all these samples.
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PMID:Heat aggregation studies of phycobilisomes, ferritin, insulin, and immunoglobulin by dynamic light scattering. 181 75

Iron absorption by intestinal epithelial cells, passage onto plasmatic apotransferrin, and regulation of the process remain largely misunderstood. To investigate this problem, we have set up an in vitro model, consisting in CaCo2 cells (a human colon adenocarcinoma line, which upon cultivation displays numerous differentiation criteria of small intestine epithelial cells). Cells are cultivated in a serum-free medium, containing 1 microgram/ml insulin, 1 ng/ml epidermal growth factor, 10 micrograms/ml albumin-linoleic acid, 100 nM hydrocortisone, and 2 nM T3 on new, transparent, Cyclopore polyethyleneterephthalate microporous membranes coated with type I collagen. Cells rapidly adhere, grow, and form confluent monolayers; after 15 days, scanning electron microscopy reveals numerous uniform microvilli. Domes, which develop on nonporous substrata, are absent on high porosity membranes. Culture medium from upper and lower compartments of microplate inserts and cell lysates were immunoprecipitated after labeling with [3H]glucosamine and leucine; analysis was done by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), followed by autoradiography. [3H]transferrin is found mainly in the lower compartment and in cells; [3H]apolipoprotein B is released in both compartments, and fibronectin almost entirely recovered in the lower compartment; [3H]transferrin receptors and ferritin are only present in cell lysates. Binding experiments also show that transferrin receptors are accessible from the lower compartment. These results suggest that CaCo2 cells, cultivated in synthetic medium on membranes of appropriate porosity, could provide an in vitro model of the intestinal barrier, with the upper compartment of the culture insert corresponding to the apical pole facing the intestinal lumen and the lower one to the basal pole in contact with blood.
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PMID:Iron absorption by intestinal epithelial cells: 1. CaCo2 cells cultivated in serum-free medium, on polyethyleneterephthalate microporous membranes, as an in vitro model. 183 Mar 3

We investigated the possibility that insulin could stimulate translation of ornithine decarboxylase (ODC) mRNA in a murine fibroblast cell line that expresses large numbers of human insulin receptors (HIR 3.5 cells). Within 3 h after exposure to 70 nM insulin, ODC enzyme activity increased approximately 50-fold and mRNA accumulation 3-fold in the HIR 3.5 cells but not in normal fibroblasts. Pretreatment of cells with cycloheximide completely inhibited insulin-stimulated ODC expression; actinomycin D partially inhibited this effect. To determine the influence of the 5' untranslated region (5'UTR) of ODC mRNA on insulin-regulated ODC expression, plasmids were constructed which contained sequences from the 5'UTR of a rat ODC mRNA interposed between the ferritin promoter and the coding region of the human growth hormone gene. These constructions were then expressed transiently in HIR 3.5 cells. Insulin stimulated a 2-4-fold change in growth hormone accumulation in the medium of cells transiently expressing plasmids containing the entire 5'UTR of ODC mRNA or just the 5'-most 115 bases, a G/C-rich conserved sequence predicted to form a stem-loop structure and shown previously to be responsible for constitutive inhibition of translation. There was a direct correlation between the extent of insulin stimulation and the predicted secondary structure of the added 5'UTR sequences. To determine whether this effect might be due to insulin activation of initiation factors responsible for melting mRNA secondary structure, we examined the effect of insulin on the phosphorylation states of two such factors, eucaryotic initiation factors eIF-4B and eIF-4E. Insulin stimulated the phosphorylation of both initiation factors; this stimulation was evident at 15 min and maximal by 60 min. These results suggest a potential general mechanism by which insulin could preferentially stimulate translation of mRNAs whose 5'UTRs exhibit significant secondary structure by activating initiation factors involved in melting such secondary structures.
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PMID:Insulin induction of ornithine decarboxylase. Importance of mRNA secondary structure and phosphorylation of eucaryotic initiation factors eIF-4B and eIF-4E. 198 89

Recent data have shown that ferritin, a ubiquitous protein, has a role as a regulator of cellular differentiation. In the present study we have investigated the expression of ferritin mRNAs in cultured C6 cells, a rat glioma cell line, in response to insulin, which has an important role in cellular growth and differentiation. Insulin stimulated steady state levels of both ferritin heavy chain and ferritin light chain mRNAs. An increase in the level of ferritin heavy or light chain mRNA was detected after 2 h of incubation with insulin, and a plateau was reached after 48 h for heavy chain mRNA and after 72 h for light chain mRNA. The responses were dose-dependent and were maximal at 100 nM for both mRNAs. Treatment of cells with actinomycin-D showed that insulin had no effect on the posttranscriptional stability of these mRNAs. Actinomycin-D inhibited insulin-induced accumulation of both mRNAs, suggesting transcriptional stimulation of ferritin genes by insulin. A nuclear run-on assay showed that the insulin-induced increase in ferritin heavy chain mRNA was due to an increase in the rate of gene transcription. We also demonstrated that insulin-like growth factor-I (IGF-I) increased ferritin heavy and light chain mRNA levels in a dose-dependent fashion, and that the maximum effect was obtained at a concentration of 10 nM on both mRNA levels. IGF-I was not only 10-fold more potent, but the absolute level of maximum stimulation was also about 2-fold greater than that for insulin. The combination of insulin (100 nM) and IGF-I (10 nM) showed no additive effect. The results suggested that the ferritin heavy and light chain genes are transcriptionally regulated by insulin and influenced by IGF-I.
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PMID:Transcriptional regulation of ferritin messenger ribonucleic acid levels by insulin in cultured rat glioma cells. 199 66

Plasma levels of retinol binding protein (RBP), prealbumin, total protein, albumin, transferrin and ferritin were estimated in three groups of diabetic patients seen at a diabetes centre in S. India. The groups consisted of patients with fibrocalculous pancreatic diabetes (FCPD), non-insulin-dependent diabetes mellitus (NIDDM) and insulin-dependent diabetes mellitus (IDDM). Mean RBP levels were lower in FCPD and IDDM patients compared to controls but this did not reach statistical significance. Prealbumin levels were normal in FCPD patients, but low in IDDM compared to controls (P less than 0.005) and NIDDM (P less than 0.05). FCPD patients had lower transferrin levels compared to controls (P less than 0.05). There were no differences in the levels of total protein, albumin and ferritin in any of the study groups. The study shows that biochemical evidence of undernutrition is seen in FCPD and IDDM patients while NIDDM patients are not significantly different from non-diabetic control subjects.
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PMID:Nutritional profile of fibrocalculous pancreatic diabetes and primary forms of diabetes seen in southern India. 203 42

We examined the effect of thyrotropin (TSH) stimulation of FRTL5 rat thyroid cells on ferritin H mRNA levels. On Northern blot analysis, TSH (in the presence of serum and insulin) increased ferritin H mRNA levels, with an initial response evident after 1 h of stimulation. Ferritin H mRNA levels increased approximately 4-fold over basal levels after 4 h of TSH stimulation and showed little increase thereafter, maintaining a plateau for up to 48 h of TSH stimulation. Inducers of cAMP also increased ferritin H mRNA levels in FRTL5 cells to about the same extent, but the rate of response was not as rapid as with TSH stimulation. In serum-poor medium without insulin, the TSH effect was considerably weaker, increasing only about 2-fold after 24 h of stimulation. Also in serum-poor medium, insulin-like growth factor-I alone had a weak stimulatory effect on ferritin H mRNA levels. TSH and insulin-like growth factor-I had additive effects under these conditions. Nuclear run-on transcription assays were performed using nuclei prepared from FRTL5 cells. In serum-containing medium, TSH increased the transcriptional activity of ferritin H mRNA 3-4-fold without an increase in beta-actin transcriptional activity. The kinetics of TSH stimulation of ferritin H transcriptional activity were similar to the cellular ferritin H mRNA response to TSH stimulation. Dibutyryl-cAMP (dB-cAMP) increased ferritin H transcriptional activity about 4-fold, but not as rapidly as did TSH stimulation. In summary, our data indicate that ferritin H mRNA levels in FRTL5 thyroid cells are transcriptionally regulated by both TSH and dBcAMP stimulation. These data contrast with the predominantly nontranscriptional regulation of ferritin H mRNA levels observed in other tissues. The difference in the kinetics of the response to TSH and dBcAMP is consistent with the concept that not all effects induced by TSH stimulation of thyroid cells are mediated by cAMP as a second messenger.
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PMID:Transcriptional regulation of ferritin H messenger RNA levels in FRTL5 rat thyroid cells by thyrotropin. 215 9

Claims that juvenile delinquency may be associated with reactive hypoglycemia or nutritional deficiencies have received widespread attention but little objective evaluation. To assess the validity of these claims, nutritional and psychological indices of juvenile delinquents have been measured. Serum glucose and insulin profiles during an oral sucrose tolerance test were measured in 137 delinquent and 41 nondelinquent male adolescents aged 14 to 19. In addition, nutritional status of both populations was assessed by anthropometry (height, weight, arm circumference, triceps skin fold) and biochemical measures (hematocrit, red-blood cell thiamin, and serum copper, ferritin, and zinc). Delinquent subjects had slightly but significantly lower serum glucose values at four of six time points (fasting, 60 minutes, 120 minutes, 180 minutes) and higher serum insulin values at one time point (30 minutes) compared with nondelinquent subjects. Changes in glucose from fasting levels indicate that these subjects were regulating serum glucose adequately, but doing so at lower values; changes in insulin from fasting levels indicate that black delinquents initially secreted more insulin than either white subject group. There were no significant associations between excursions in serum glucose or insulin and any adrenergic signs or symptoms of low blood glucose levels. Nutritional status of incarcerated delinquents did not differ from that of nonincarcerated subjects on most measures. Although the significantly lower serum glucose levels and higher serum insulin levels are intriguing, no support is offered by results of this study for allegations that sucrose ingestion causes reactive hypoglycemia in juvenile delinquents or that delinquent male adolescents are at greater risk nutritionally than male adolescents of the same age who are not delinquent.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Sucrose and delinquency: oral sucrose tolerance test and nutritional assessment. 219 23


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