Hemochromatosis/genetics* ; Histocompatibility Antigens Class I/genetics* ; Humans ; Mutation ; Receptors, Transferrin/genetics*

Obesity is a major health problem across the world, but there are few ways to effectively treat or manage it in the long term. Researchers are searching for more convenient, cost-effective and noninvasive therapies for overweight and obese people. Recent studies have illustrated that the microbiome of the body's different organs can be used as a vehicle for in-situ gene therapy. We suggest that the recombinant form of "Pichia pastoris" yeast expressing the hybrid protein of "irisin-furin-transferrin" under the control of the enolase 1 promoter is a new nutraceutical strategy to absorb fewer calories from intestinal nutrients, and induce a higher metabolic rate to expend more calories, similar to that from engaging in physical activity. By comparison, this method can be a long-term, noninvasive treatment and can be used for obese patients who have movement limitations.
Fibronectins ; genetics ; Furin ; genetics ; Genetic Therapy ; Humans ; Obesity ; therapy ; Pichia ; genetics ; Recombinant Fusion Proteins ; genetics ; Transferrin ; genetics ; Weight Loss

The fused gene (PTH-TFN) of parathyroid hormone (PTH) gene and transferring N-terminal half-molecule (TFN) gene was amplified by multiple PCR and inserted into pPIC9 vector. The recombinant plasmid pPIC9-PTH-TFN was transformed into Pichia pastoris GS115 by PEG. After methanol induction, the target protein was expressed in fermentation supernatant at high level. The fused protein PTH-TFN with purity being higher than 95% was finally obtained after purification through two-step chromatography: SP Sepharose Fast Flow and Phenyl Sepharose Fast Flow. Western blot analysis and adenylate cyclase assay proved that the fused protein exhibited the bioactivity to stimulate cAMP synthesis and the ability to bind Fe3+ in the Fe3+ saturation study as the recombinant TFN did indicating that TFN could be used as the transcellar carrier of PTH.
Artificial Gene Fusion ; Cloning, Molecular ; Humans ; Parathyroid Hormone ; genetics ; Pichia ; genetics ; metabolism ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; Transferrin ; genetics

Human transferrin receptor (TfR) was isolated from homogenates of placental tissues by affinity chromatography on transferrin-Sepharose, and then used to screen human scFv against it from a fully-synthesized phage scFv library. After verifying the specificity, gene fragment of one of the selected scFv was inserted into the plasmid pET22b(+) and transformed into E. coli BL21(DE3) . Expression of scFv in transformant was induced with 0.5mmol/L IPTG. ELISA assay on HeLa cells showed that scFv protein could recognize and bind to TfR on the surface of HeLa cells. The scFv was purified by one-step affinity chromatography with Ni+ -NTA agarose, and injected into Kunming mouse via tail veins. This scFv was detected in brain tissues 1h later by capillary depletion method, which indicates that scFv protein can permeate through the blood brain barrier by mediation of the TfR receptor. Our works lay the foundation for the treatment of tumors and central nervous system diseases.
Animals ; Antibodies, Anti-Idiotypic ; genetics ; isolation & purification ; metabolism ; Escherichia coli ; genetics ; metabolism ; HeLa Cells ; Humans ; Immunoglobulin Fragments ; biosynthesis ; genetics ; immunology ; Immunoglobulin Variable Region ; biosynthesis ; genetics ; immunology ; Mice ; Receptors, Transferrin ; genetics ; immunology ; Recombinant Proteins ; biosynthesis ; genetics ; Transferrin ; metabolism

Iron homeostasis plays an important role for the maintenance of human health. It is known that iron metabolism is tightly regulated by several key genes, including divalent metal transport-1(), transferrin receptor 1(), transferrin receptor 2(), ferroportin(), hepcidin(), hemojuvelin() and . Recently, it is reported that DNA methylation, histone acetylation, and microRNA (miRNA) epigenetically regulated iron homeostasis. Among these epigenetic regulators, DNA hypermethylation of the promoter region of , and bone morphogenetic protein 6 () genes result in inhibitory effect on the expression of these iron-related gene. In addition, histone deacetylase (HADC) suppresses gene expression. On the contrary, HADC inhibitor upregulates gene expression. Additional reports showed that miRNA can also modulate iron absorption, transport, storage and utilization via downregulation of and other genes. It is noteworthy that some key epigenetic regulatory enzymes, such as DNA demethylase TET2 and histone lysine demethylase JmjC KDMs, require iron for the enzymatic activities. In this review, we summarize the recent progress of DNA methylation, histone acetylation and miRNA in regulating iron metabolism and also discuss the future research directions.
Epigenesis, Genetic ; Gene Expression Regulation ; genetics ; Homeostasis ; Humans ; Iron ; metabolism ; Receptors, Transferrin

The study was carried out to investigate the genetic polymorphism of the serum proteins of horses in Cheju. They were assigned to three groups; 45 Cheju native horses(CNH), 60 Cheju racing horses(CRH) and 60 Thoroughbreds(TB). We analyzed the phenotypes and gene frequencies of serum proteins which were albumin (Alb), vitamin-D binding protein(GC), esterase (ES), A1B glycoprotein(A1B) and transferrin(TF) loci using horizontal polyacrylamide gel electrophoresis (HPAGE).All of the loci, except A1B in TB, showed polymorphisms and different allelic and phenotypic frequencies in all three groups. ESS and TFF1 were not observed in CNH. Allelic frequencies of AlbB, ESI, TFD and TFF1 were high in TB. All of the loci, except ES locus in CRH, appeared to be in a state of Hardy-Weinberg equilibrium from goodness-of-fit test in all three groups Heterozygosity estimates at Alb, ES and TF loci were high, but GC and A1B loci were low in all three groups. Average heterozygosities in CNH, CRH and TB were 0.3535, 0.3555 and 0.2726, respectively. Results showed differences in the frequencies of alleles and phenotypes of several serum protein loci between CNH and CRH, suggested that CRH might be crossed with other breeds of horses in some degree.
Alleles ; Animals ; Blood Proteins/*genetics ; Electrophoresis, Polyacrylamide Gel ; Esterases/genetics ; Genetic Variation ; Horses/blood/*genetics ; Polymorphism, Genetic ; Serum Albumin/genetics ; Transferrin/genetics ; Vitamin D-Binding Protein/genetics

To explore the mechanism of iron metabolism and its regulation as well as the roles of IRP(2) in ion metabolism of HL-60 cells, HL-60 cells were cultured in RPMI 1640 medium supplemented with 10% heat-inactivated fetal bovine serum, which was treated with ferric chloride (FeCl(3)) or deferoxamine (DFO). The cells were harvested at 12, 24 and 48 hours of proliferation, and total RNA was isolated; cDNA was synthesized by reverse transcription (RT), and relative expression levels of IRP(2) mRNA, Fn mRNA and TfR mRNA were determined by RT-PCR. The results showed at follows: (1) the level of IRP(2) mRNA remained constant in all cells, whether or not treated with DFO or FeCl(3). However, the expression of IRP(2) mRNA decreased when the time of cell culture was prolonged. There was no significant difference between groups (F(B-S) = 1.199, P > 0.05), but there was significant difference among the different time culture (F(W-S) = 43.418, P < 0.01). (2) Cells which treated neither with DFO nor ferri chloride showed significant difference from the control (F(W-S) = 7.184, F(B-S) = 113.926; P < 0.01). The level of TfR mRNA increased in the cells treated with DFO. Surprisingly, when cells treated with FeCl(3), there was not decline of TfR mRNA expression, but it increased lightly at 12 hours and peaked at 24 hours and declined drastically at 48 hours. (3) The level of Fn mRNA in the cells treated with FeCl(3) was approximately 2-fold as the control cells. In contrast with the control cells, there was significant difference (P < 0.05). The level of Fn mRNA of the cells treated with DFO had little change. As compared with the control cells, no significant difference was seen (P > 0.05). (4) There was not any significant correlation between IRP(2) mRNA and TfR mRNA or Fn mRNA in HL-60 cells (r = -0.005; r = 0.074; P > 0.05). It is concluded that (1) IRP(2) may regulate the iron metabolism in HL-60 cells by altering amounts of the IRP(2) 3.7- or 6.4-kb mRNA at the transcriptional level, or by IRP(2) degradation at the post transcriptional level. (2) Both of Fn mRNA and TfR mRNA participated, more or less, in the iron metabolism in HL-60 cells.
Ferritins ; genetics ; Gene Expression Regulation, Neoplastic ; HL-60 Cells ; Humans ; Iron Regulatory Protein 2 ; genetics ; RNA, Messenger ; genetics ; metabolism ; Receptors, Transferrin ; genetics ; Reverse Transcriptase Polymerase Chain Reaction

OBJECTIVETo study the value of iron metabolism indices, serum iron (SI), total iron blinding capacity (TIBC) and transferring (Tf), in thalassema.

METHODSThe serum samples from 9 children with silent alpha thalassema, 56 with standard alpha thalassema, 26 with HbH disease, 40 with beta+ thalassema, 56 with beta0 thalassema, 45 with iron deficiency anemia (IDA) and 70 healthy children were detected for SI, TIBC and Tf levels.

RESULTSThe SI level increased (p<0.01), while the TIBC level decreased significantly in the beta0 thalassema group compared with those in the other groups (p<0.05 or 0.01), but the Tf level was not different. The Tf level of both the silent alpha thalassema and the standard alpha thalassema groups was statistically lower than that of the healthy group (p<0.01), but the levels of SI and TIBC were similar to the healthy group. Though the SI level of the HbH disease group was similar to the healthy group, the TIBC and Tf levels were statistically lower (p<0.01).

CONCLUSIONSCompared with Tf, SI and TIBC are better indices for monitoring iron loading in children with thalassema. The increased SI level and decreased TIBC level are two indices for the diagnosis of beta(0) thalassema in children with cellule anaemia.

Adolescent ; Anemia, Iron-Deficiency ; metabolism ; Child ; Child, Preschool ; Female ; Genotype ; Humans ; Infant ; Iron ; metabolism ; Male ; Thalassemia ; genetics ; metabolism ; Transferrin ; analysis

This article reports the effect of dihydroartemisinin (DHA) on transferrin receptor (TfR) in myeloid leukemia cells by establishing the model of normal iron HL60 and K562 cells and iron overload K562 cells in vitro. The TfR content of myeloid leukemia cells was determined by flow cytometry, and the effect of DHA on iron content in K562 cells was determined by atomic absorption spectrophotometric analysis. Furthermore, the inhibitory effect of DHA on the anti-proliferation and expression of TfR protein and mRNA in myeloid leukemia cells was studied. As a result, DHA effectively decreased the TfR content and down-regulated TfR protein expression in normal iron HL60 and K562 cells in a dose- and time-dependent manner and inhibited the cell proliferation. The IC50 were 1.74 and 11.33 micromol x L(-1), respectively. DHA exerted more pronounced inhibitory action on expression of TfR protein and mRNA in iron overload K562 cells. Compared to normal iron K562 cells, the TfR protein and mRNA levels were lowered by 28.1% (P < 0.01) and 26. 2% (P < 0. 05) , respectively, after DHA treatment for 48 h in iron overload K562 cells. Moreover, DHA decreased the iron content of iron overload K562 cells and inhibited the proliferation of iron overload K562 cells more potently. DHA effectively down-regulated the TfR content as well as expression of TfR protein and mRNA in normal iron myeloid leukemia cells. DHA also inhibited the proliferation of HL60 and K562 cells. The anti-proliferation effect of DHA on iron overload K562 cells was more striking.
Antineoplastic Agents, Phytogenic ; administration & dosage ; pharmacology ; Artemisinins ; administration & dosage ; pharmacology ; Cell Proliferation ; drug effects ; Dose-Response Relationship, Drug ; Down-Regulation ; HL-60 Cells ; Humans ; K562 Cells ; RNA, Messenger ; metabolism ; Receptors, Transferrin ; genetics ; metabolism ; Transferrin ; metabolism

Extracellular Signal-Regulated MAP Kinases ; metabolism ; Glomerular Mesangium ; immunology ; Glycosylation ; Humans ; Immunoglobulin A ; metabolism ; Phosphorylation ; Receptors, Fc ; analysis ; genetics ; Receptors, Transferrin ; analysis ; genetics