Enzyme separation, purification, immobilization, and catalytic performance improvement have been the research hotspots and frontiers as well as the challenges in the field of biocatalysis. Thus, the development of novel methods for enzyme purification, immobilization, and improvement of their catalytic performance and storage are of great significance. Herein, ferritin was fused with the lichenase gene to achieve the purpose. The results showed that the fused gene was highly expressed in the cells of host strains, and that the resulted fusion proteins could self-aggregate into carrier-free active immobilized enzymes in vivo. Through low-speed centrifugation, the purity of the enzymes was up to > 90%, and the activity recovery was 61.1%. The activity of the enzymes after storage for 608 h was higher than the initial activity. After being used for 10 cycles, it still maintained 50.0% of the original activity. The insoluble active lichenase aggregates could spontaneously dissolve back into the buffer and formed the soluble polymeric lichenases with the diameter of about 12 nm. The specific activity of them was 12.09 times that of the free lichenase, while the catalytic efficiency was 7.11 times and the half-life at 50 ℃ was improved 11.09 folds. The results prove that the ferritin can be a versatile tag to trigger target enzyme self-aggregation and oligomerization in vivo, which can simplify the preparation of the target enzymes, improve their catalysis performance, and facilitate their storage.
Biocatalysis ; Enzymes, Immobilized/metabolism* ; Ferritins/metabolism* ; Glycoside Hydrolases/metabolism*

The aim of this study was to investigate the effects of polarization program on the ability of macrophages to regulate iron metabolism. M1 and M2 macrophages were propagated in vitro from porcine alveolar macrophages 3D4/2 and polarized by cytokines. The 3D4/2 macrophages were treated with 20 ng/mL interferon gamma (IFN-γ) and 10 ng/mL interleukin-4 (IL-4) combined with 10 ng/mL macrophage colony-stimulating factor (M-CSF) to induce polarization to M1 and M2, respectively. After incubation for 24 h, the expression levels of inflammatory factors and iron-metabolism genes were determined using real-time qPCR, Western bot and immunofluorescence. The M1/M2 macrophages culture media supernatant was collected and used to treat porcine intestinal epithelial cells IPEC-J2. The proliferation ability of IPEC-J2 was detected using CCK-8 assay kit. Following exogenous addition of ammonium ferric citrate (FAC) to M1/M2 macrophages, the phagocytic function of macrophages was detected using fluorescein isothiocyanate-dextran (FITC-dextran) and flow cytometry. The results showed that, compared with control, M1 macrophages had higher mRNA levels of iron storage proteins (ferritin heavy and light polypeptide, i.e. FtH and FtL), hepcidin and lipocalin-2, as well as iron content. Moreover, iron enhanced the ability of M1 macrophages to phagocytize FITC-dextran. There was no significant change in these mRNA expression levels in M2 macrophages, but the mRNA expression levels of ferroportin and transferrin receptor were up-regulated. In addition, the conditioned media supernatant from M2 macrophages promoted cell proliferation of IPEC-J2. These findings indicate that M1 macrophages tend to lock iron in the cell and reduce extracellular iron content, thereby inhibiting the proliferation of extracellular bacteria. While M2 macrophages tend to excrete iron, which contributes to the proliferation of surrounding cells and thus promotes tissue repair.
Animals ; Cytokines ; Ferritins ; Iron/metabolism* ; Macrophages/metabolism* ; Macrophages, Alveolar/metabolism* ; Swine

Animals ; Blood-Brain Barrier ; metabolism ; Ferritins ; metabolism ; Horses ; Mice ; Receptors, Transferrin ; metabolism ; Spleen ; chemistry

OBJECTIVETo investigate the multiple iron metabolism-related genes expression, its regulation by iron and the expression correlation among the genes in rat tissues.

METHODSTwo groups (n=30) of Sprague-Dawley female weanling rats were fed with a control diet and an iron deficient diet respectively for 4 weeks. All rats were then sacrificed, and blood and tissue samples were collected. The routine blood examination was performed with a veterinary automatic blood cell analyzer. Elemental iron levels in liver, spleen and serum were determined by atomic absorption spectrophotometry. The mRNA expression of genes was detected by real-time fluorescence quantitative PCR.

RESULTSAfter 4 weeks, the hemoglobin (Hb) level and red blood cell (RBC) count were significantly lower in the iron deficient group compared with those in the control group. The iron levels in liver, spleen and serum in the iron deficient group were significantly lower than those in the control group. In reference to small intestine, the relative expression of each iron-related gene varied in the different tissues. Under the iron deficiency, the expression of these genes changed in a tissue-specific manner. The expression of most of the genes significantly correlated in intestine, spleen and lung, but few correlated in liver, heart and kidney.

CONCLUSIONFindings from our study provides new understandings about the relative expression, regulation by iron and correlation among the mRNA expressions of transferrin receptors 1 and 2, divalent metal transporter 1, ferritin, iron regulation proteins 1 and 2, hereditary hemochromatosis protein, hepcidin, ferroportin 1 and hephaestin in intestine, liver, spleen, kidney, heart, and lung of rat.

Animals ; Ferritins ; blood ; Gene Expression ; Hepcidins ; Iron ; Liver ; metabolism ; Rats ; Rats, Sprague-Dawley

BACKGROUND: Hepcidin, a key regulator of iron homeostasis, is associated with iron metabolism imbalance in patients with chronic kidney disease (CKD). However, serum hepcidin level in anemic patients with CKD presents a contradictory picture. We investigated the relationship between serum hepcidin-25 level and iron parameters in patients with CKD. METHODS: We defined and categorized patients with CKD according to the Kidney Disease Outcomes Quality Initiative (KDOQI) guidelines. We analyzed the relationship between serum hepcidin-25 level and iron parameters [serum iron, total iron-binding capacity (TIBC), unbound iron-binding capacity (UIBC), transferrin saturation, and ferritin levels] according to the CKD stage and clinical and laboratory characteristics. RESULTS: Hb level, TIBC, and UIBC decreased and ferritin level increased (Ptrend<0.001) (stage 1-2, 28; stage 3, 40; stage 4, 36; stage 5, 42) as the CKD stage progressed. Serum hepcidin-25 level showed no significant trend with the progressing CKD stage [stage 1-2, 13.7 (3.7-25.0) ng/mL; stage 3, 14.0 (0.8-26.5) ng/mL; stage 4, 13.9 (2.0-32.1) ng/mL; stage 5, 13.8 (0.5-42.4) ng/mL; Ptrend=0.618]. No significant relationship was noted between serum hepcidin-25 level and kidney function parameters, Hb levels, or iron parameters (P>0.05). CONCLUSIONS: Serum hepcidin-25 level was not found to be associated with iron parameters or clinical status of CKD patients in our study. Determination of hepcidin-25 levels may not provide more information than conventional iron parameters in monitoring iron metabolism in CKD patients. However, further studies are needed to establish the clinical utility of hepcidin measurement in CKD patients.
Anemia ; Ferritins ; Hepcidins* ; Homeostasis ; Humans ; Iron* ; Kidney ; Kidney Diseases ; Metabolism ; Renal Insufficiency, Chronic* ; Transferrin

Adult ; Ferritins ; blood ; Humans ; Leukocytes ; metabolism ; Lymphohistiocytosis, Hemophagocytic ; blood ; diagnosis ; Male ; Panniculitis ; blood ; diagnosis ; Triglycerides ; blood

OBJECTIVE: To detect serum hepcidin and erythroferrone levels in child-bearing women with iron deficiency anemia (IDA), and to investigate the association between them and iron status parameters. METHODS: The study consisted of 65 child-bearing women (35 with iron deficiency anemia and 30 age-matched healthy women). The levels of serum iron were detected by using automated chemistry analyzer, the contents of serum ferritin were detected by electrochemiluminescence immunoassay, and the levels of serum erythroferrone and hepcidin were detected by specific enzyme-linked immunosorbent assay (ELISA) kit. The quantitative variables between two groups were compared and analyzed by SPSS22.0 software. Spearman correlation was used to detect correlation between the parameters. RESULTS: The levels of Hb, serum iron, ferritin and transferrin saturation were significantly decreased in IDA patients as compared with in control group (P<0.001). Serum hepcidin levels in IDA patients were significant lower than those in control group (P<0.001). Serum erythroferrone levels slightly increased in IDA group (P>0.05). In IDA patients, serum hepcidin concentrations were positively correlated with hemoglobin concentration, serum iron, serum ferritin and transferrin saturation (r=0.448, r=0.496, r=0.754, r=0.491). But, serum erythroferrone concentrations showed no correlation with hemoglobin concentration, serum iron, serum ferritin, transferrin saturation and hepcidin (P>0.05). CONCLUSION Serum hepcidin levels were significantly decreased in child-bearing women with IDA, but the serum erythroferrone levels were not obviously different between two groups, suggesting that serum erythroferrone may be not involved in the regulation of iron metabolism in child-bearing women with mild and moderate IDA.
Anemia, Iron-Deficiency ; Child ; Enzyme-Linked Immunosorbent Assay ; Female ; Ferritins ; Hepcidins ; Humans ; Iron/metabolism*

Objective: To analyze the influencing factors of iron metabolism assessment in patients with myelodysplastic syndrome. Methods: MRI and/or DECT were used to detect liver and cardiac iron content in 181 patients with MDS, among whom, 41 received regular iron chelation therapy during two examinations. The adjusted ferritin (ASF) , erythropoietin (EPO) , cardiac function, liver transaminase, hepatitis antibody, and peripheral blood T cell polarization were detected and the results of myelofibrosis, splenomegaly, and cyclosporine were collected and comparative analyzed in patients. Results: We observed a positive correlation between liver iron concentration and ASF both in the MRI group and DECT groups (r=0.512 and 0.606, respectively, P<0.001) , only a weak correlation between the heart iron concentration and ASF in the MRI group (r=0.303, P<0.001) , and no significant correlation between cardiac iron concentration and ASF in the DECT group (r=0.231, P=0.053) . Moreover, transfusion dependence in liver and cardiac [MRI group was significantly associated with the concentration of iron in: LIC: (28.370±10.706) mg/g vs (7.593±3.508) mg/g, t=24.30, P<0.001; MIC: 1.81 vs 0.95, z=2.625, P<0.05; DECT group: liver VIC: (4.269±1.258) g/L vs (1.078±0.383) g/L, t=23.14, P<0.001: cardiac VIC: 1.69 vs 0.68, z=3.142, P<0.05]. The concentration of EPO in the severe iron overload group was significantly higher than that in the mild to moderate iron overload group and normal group (P<0.001) . Compared to the low-risk MDS group, the liver iron concentration in patients with MDS with cyclic sideroblasts (MDS-RS) was significantly elevated [DECT group: 3.80 (1.97, 5.51) g/L vs 1.66 (0.67, 2.94) g/L, P=0.004; MRI group: 13.7 (8.1,29.1) mg/g vs 11.6 (7.1,21.1) mg/g, P=0.032]. Factors including age, bone marrow fibrosis, splenomegaly, T cell polarization, use of cyclosporine A, liver aminotransferase, and hepatitis antibody positive had no obvious effect on iron metabolism. Conclusion: There was a positive correlation between liver iron concentration and ASF in patients with MDS, whereas there was no significant correlation between cardiac iron concentration and ASF. Iron metabolism was affected by transfusion dependence, EPO concentration, and RS.
Ferritins ; Humans ; Iron ; Iron Overload ; Liver/metabolism* ; Myelodysplastic Syndromes/therapy* ; Primary Myelofibrosis ; Retrospective Studies ; Splenomegaly

OBJECTIVE: To investigate the correlation of iron metabolic parameters with platelet counts in blood donors. METHODS: A total of 400 blood donors who met requirements of apheresis platelet donation were collected, and their hematological parameters were analyzed. The donors were divided into low ferritin group and normal group, the differences of hematological parameters between the two groups were compared, and the correlation of iron metabolic parameters and routine hematology parameters with platelet counts were analyzed. RESULTS: Whether male or female, low ferritin group had higher platelet counts than normal group (P < 0.01). Among the iron metabolic parameters, the platelet counts was negatively correlated with serum ferritin (SF), serum iron (SI), and transferrin saturation (TSAT) (r =-0.162, r =-0.153, r =-0.256), and positively correlated with total iron binding capacity (TIBC) and unsaturated iron binding capacity (UIBC) (r =0.219, r =0.294) in female blood donors. Platelet counts was also negatively correlated with SF, SI and TSAT (r =-0.188, r =-0.148, r =-0.224) and positively correlated with UIBC (r =0.220) in male blood donors. Among the routine hematology parameters, platelet counts was negatively correlated with mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), and reticulocyte hemoglobin equivalent (Ret-He) in female blood donors (r =-0.236, r =-0.267, r =-0.213, r =-0.284). Platelet counts was also negatively correlated with MCH, MCHC and Ret-He in male blood donors (r =-0.184, r =-0.221, r =-0.209). CONCLUSION In blood donors with low C-reactive protein level, the lower the iron store capacity, the lower the iron utilization, and the platelet counts tends to rise.
Male ; Humans ; Female ; Iron/metabolism* ; Blood Donors ; Platelet Count ; Anemia, Iron-Deficiency ; Hemoglobins ; Ferritins

This study was purposed to investigate the iron metabolism changes and their clinical significance in myelodysplastic syndrome (MDS). Thirty eight transfusion independent MDS patients and 49 controls (21 AA patients, 28 normal volunteers) were enrolled in this study. The iron metabolism indicators including serum iron protein (SF), serum iron (SI), transferrin protein (Tf), total iron binding capacity (TIBC), transferrin saturation (TS), soluble transferrin receptor (sTfR) were detected, the intracellular and extracellular iron distribution were observed under microscope, the chromosome karyotype was analysis by FISH. The results showed that the serum SF, SI and TS levels in MDS group were lower than those in AA group, the serum SF value was higher than that in normal control group. There was no statistical difference between the SI, TS levels as compared with normal control group. The SI, TS levels showed a positive correlation with SF level(r = 0.281, P = 0.007; r = 0.338, P = 0.001, respectively). The serum TIBC in MDS group was no statistically significant difference from that in the control group. The Tf level in MDS group was higher than that in AA and normal control groups, and Tf level between later 2 groups did not show statistical difference. The proportion of sideroblasts in MDS group (57.19 ± 19.11%)was higher than that in AA group (35.00 ± 20.67%). The extracellular iron (+ + +- + + + +) (24%)was lower than that in AA group (33%), and bone marrow particle dyeable iron displayed mainly cocci-like distribution under microscope in patients with increased extracellular iron (+ + +- + + + +), while small need or massive distribution was observed in AA group.In addition, the abnormal chromosome karyotype was found in 15 out of 19 MDS cases (79%). There was no difference in iron metabolism indicators between the high-risk group and the low-risk group of MDS divided according to the International Prognostic Scoring System (WPSS). It is concluded that the iron loading in transfusion-independent patients obviously increases, displaying the enhancement of SF, Tf, intra-and extra-cellular iron, but lower than those in AA patients. It suggests that the abnormality exists in process of use, storage and discharge of iron in MDS patients.
Adult ; Case-Control Studies ; Female ; Ferritins ; blood ; Hematopoiesis ; Humans ; Iron ; blood ; metabolism ; Male ; Middle Aged ; Myelodysplastic Syndromes ; blood ; metabolism ; physiopathology ; Receptors, Transferrin ; metabolism ; Transferrin ; metabolism