OBJECTIVES: To observe the evolution of intrahepatic macrophage polarization in mice with liver fibrosis induced by iron overload. METHODS: Thirty-two C57BL/6 mice (6-8 weeks) were randomized into control group (n=8) and liver fibrosis model group (n=24) induced by aidly intraperitoneal injection of iron dextran. At the 3rd, 5th, and 7th weeks of modeling, 8 mice in the model group were sacrificed for observing liver fibrosis using Masson, Sirius Red and immunohistochemical staining and detecting serum levels of ALT, AST and the levels of serum iron, ferritin, liver total Fe and ferrous Fe. iNOS⁺/F4/80⁺ cells and CD206⁺/F4/80⁺ cells were detected by double immunofluorescence assay to observe the proportion and distribution of M1 and M2 macrophages. The hepatic expressions of Arg-1, iNOS, IL-6, IL-10, and TNF‑α proteins were detected using Western blotting or ELISA, and the expression of CD206 mRNA was detected using RT-PCR. RESULTS: The mice in the model group showed gradual increase of fibrous tissue hyperplasia in the portal area over time, structural destruction of the hepatic lobules and formation of pseudolobules. With the passage of time during modeling, the rat models showed significantly increased hepatic expressions of α-SMA and COL-1, elevated serum levels of ALT, AST, Fe, ferritin, and increased liver total Fe and ferrous Fe levels. The expressions of M1 polarization markers IL-6, TNF‑α, and iNOS all increased with time and reached their peak levels at the 3rd week; The expressions of M2 polarization markers (IL-10 and Arg-1 proteins and CD206 mRNA) significantly increased in the 3rd week and but decreased in the 5th and 7th weeks. CONCLUSIONS Iron overload promotes M1 polarization of macrophages in mice. Liver fibrosis in the early stage promotes M2 polarization of macrophages but negatively regulate M2 polarization at later stages.
Animals ; Mice ; Mice, Inbred C57BL ; Iron Overload/pathology* ; Macrophages/metabolism* ; Male ; Liver Cirrhosis/etiology* ; Nitric Oxide Synthase Type II/metabolism* ; Interleukin-10/metabolism* ; Liver/pathology* ; Interleukin-6/metabolism* ; Mannose Receptor ; Tumor Necrosis Factor-alpha/metabolism* ; Mannose-Binding Lectins/metabolism* ; Arginase

It is reported that iron metabolism and ferroptosis can influence the occurrence and development of myeloid tumors, which can serve as therapeutic targets. Dysregulation of iron metabolism is present in a variety of myeloid neoplasms. The prognosis of acute myeloid leukemia is related to differential expression of molecules related to iron metabolism. The prognosis of myelodysplastic syndrome patients with iron overload is poor. Myeloproliferative neoplasms are often characterized by the coexistence of iron deficiency and erythrocytosis, which can be treated by targeting hepcidin. Myeloid tumor cells are susceptible to oxidative damage caused by the accumulation of reactive oxygen species and are sensitive to ferroptosis. Ferroptosis has anti-tumor effect in acute myeloid leukemia and myelodysplastic syndrome. Targeting ferroptosis can reverse imatinib resistance in chronic myeloid leukemia. This article reviews the characteristics of iron metabolism in the development and progression of myeloid neoplasms, as well as the mechanism of ferroptosis, to provide a basis for the development of new therapeutic strategies.
Ferroptosis ; Humans ; Iron/metabolism* ; Myelodysplastic Syndromes/pathology* ; Reactive Oxygen Species/metabolism* ; Leukemia, Myeloid, Acute/pathology* ; Hepcidins/metabolism* ; Iron Overload/metabolism* ; Myeloproliferative Disorders/metabolism* ; Prognosis

The aim of the present study was to investigate the role of ferroptosis in acute lung injury (ALI) mouse model induced by oleic acid (OA). ALI was induced in the mice via the lateral tail vein injection of pure OA. The histopathological score of lung, lung wet-dry weight ratio and the protein content of bronchoalveolar lavage fluid (BALF) were used as the evaluation indexes of ALI. Iron concentration, glutathione (GSH) and malondialdehyde (MDA) contents in the lung tissues were measured using corresponding assay kits. The ultrastructure of pulmonary cells was observed by transmission electron microscope (TEM), and the expression level of prostaglandin-endoperoxide synthase 2 (PTGS2) mRNA was detected by quantitative polymerase chain reaction (q-PCR). Protein expression levels of glutathione peroxidase 4 (GPX4), ferritin and transferrin receptor 1 (TfR1) in lung tissues were determined by Western blot. The results showed that histopathological scores of lung tissues, lung wet-dry weight ratio and protein in BALF in the OA group were higher than those of the control group. In the OA group, the mitochondria of pulmonary cells were shrunken, and the mitochondrial membrane was ruptured. The expression level of PTGS2 mRNA in the OA group was seven folds over that in the control group. Iron overload, GSH depletion and accumulation of MDA were observed in the OA group. Compared with the control group, the protein expression levels of GPX4 and ferritin in lung tissue were down-regulated in the OA group. These results suggest that ferroptosis plays a potential role in the pathogenesis of ALI in our mouse model, which may provide new insights for development of new drugs for ALI.
Acute Lung Injury ; chemically induced ; pathology ; Animals ; Apoptosis ; Bronchoalveolar Lavage Fluid ; chemistry ; Cyclooxygenase 2 ; metabolism ; Ferritins ; metabolism ; Glutathione ; analysis ; Glutathione Peroxidase ; metabolism ; Iron ; analysis ; Iron Overload ; physiopathology ; Lung ; cytology ; pathology ; Malondialdehyde ; analysis ; Mice ; Microscopy, Electron, Transmission ; Mitochondrial Membranes ; ultrastructure ; Oleic Acid

OBJECTIVETo investigate the effects of iron overload on apoptosis and function of splenic CD8+ T cells in mice.

METHODSForty C57BL/6 mice were randomly divided into control groups, Iron overload (IO), IO+NAC and IO+DFX groups. The iron overload model was established by intraperitoneal injection of iron dextran, and saline was injected as the control. The levels of intracellular reactive oxygen species (ROS) and labile iron pool (LIP) were analyzed by measuring the mean fluorescence intensity (MFI) of 2-7 dichlorofluorescein (DCF) or calcein. The ratio of CD8+ T cells and the levels of IFN-γ, TNF-α, Granzyme-B, and perforin in CD8+ T cells were detected by flow cytometry. The CD8+ T cell apoptosis was determined by flow cytometry with Annexin V/PI double staining. Real-time PCR was used to detect the expression of IFN-γ, TNF-α, Granzyme-B, perforin, BCL-2, and bax at mRNA level in CD8+ T cells.

RESULTSIron overload was found by spleen iron staining and flow cytometry. The level of intracellular ROS in iron overload (IO) groups was higher than that of the control groups (P<0.01). The percentage of CD8+ T cells in spleen from mice with IO was lower than that in control groups (P<0.05). The expression of IFN-γ and Granzyme-B in CD8+ T cells in IO group were lower than that in control group, the expression of IFN-γ and Granzyme-B at mRNA level in CD8+ T cells was lower than that of control group (P<0.05). CD8+ T cell apoptosis in iron overload group was significantly higher than that in control groups (P<0.01); the expression of BCL-2 at mRNA level was lower than that in control group, but the expression of BAX at mRNA level was higher than that in control group (P<0.05). These effects could be reversed after treating iron-overloaded mice with DFX or NAC.

CONCLUSIONIron overload can inhibit the ratio of CD8+ T cells of splenic cells in mice, decrease the expression of IFN-γ, Granzyme-B, increase the apoptosis of CD3+ CD8+/CD8-. These effects may be regulated through increasing the intracellular ROS level, and can be partially reversed after treating iron-overloaded mice with DFX or NAC.

Animals ; Apoptosis ; CD8-Positive T-Lymphocytes ; cytology ; pathology ; Granzymes ; metabolism ; Interferon-gamma ; metabolism ; Iron ; metabolism ; Iron Overload ; physiopathology ; Mice ; Mice, Inbred C57BL ; Perforin ; metabolism ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Random Allocation ; Reactive Oxygen Species ; metabolism ; Spleen ; cytology ; Tumor Necrosis Factor-alpha ; metabolism ; bcl-2-Associated X Protein ; metabolism

OBJECTIVE: To evaluate the diagnostic performance of magnetic resonance elastography (MRE) for staging hepatic fibrosis in patients with chronic hepatitis B virus (HBV) infection. MATERIALS AND METHODS: Patients with chronic HBV infection who were suspected of having focal or diffuse liver diseases (n = 195) and living donor candidates (n = 166) underwent MRE as part of the routine liver MRI examination. We measured liver stiffness (LS) values on quantitative shear stiffness maps. The technical success rate of MRE was then determined. Liver cell necroinflammatory activity and fibrosis were assessed using histopathologic examinations as the reference. Areas under the receiver operating characteristic curve (Az) were calculated in order to predict the liver fibrosis stage. RESULTS: The technical success rate of MRE was 92.5% (334/361). The causes of technical failure were poor wave propagation (n = 12), severe respiratory motion (n = 3), or the presence of iron deposits in the liver (n = 12). The mean LS values, as measured by MRE, increased significantly along with an increase in the fibrosis stage (r = 0.901, p < 0.001); however, the mean LS values did not increase significantly along with the degree of necroinflammatory activity. The cutoff values of LS for > or = F1, > or = F2, > or = F3, and F4 were 2.45 kPa, 2.69 kPa, 3.0 kPa, and 3.94 kPa, respectively, and with Az values of 0.987-0.988. CONCLUSION: MRE has a high technical success rate and excellent diagnostic accuracy for staging hepatic fibrosis in patients with chronic HBV infection.
Adolescent ; Adult ; Aged ; *Elasticity Imaging Techniques ; Female ; Hepatitis B, Chronic/complications/*diagnosis ; Humans ; Iron Overload/diagnosis ; Liver Cirrhosis/*diagnosis/pathology ; Living Donors ; Male ; Middle Aged ; Movement ; ROC Curve ; Respiration ; Young Adult

OBJECTIVETo assess the value of magnetic resonance imaging T2* tests in the detection of myocardial and liver iron overload in patients with β-thalassemia major (β-TM).

METHODSFrom 2010 to 2011, 28 β-TM patients over 10 years old under blood transfusion therapy and chelation care with serum ferritin (SF)>1000 µg/L underwent myocardial and liver MRI T2* tests on a voluntary basis. The results were analyzed in relation with age, SF, and left ventricular ejection fraction (LVEF).

RESULTSFourteen out of the 28 cases (50%) were found to have myocardial iron overload, including 7 severe cases, 2 moderate cases, and 5 mild cases. All the 28 cases had liver iron overload, including 2 mild cases, 7 moderate cases, and 19 severe cases. Two out of the 28 cases had lowered LVEF (7.14%), and one of them had severe myocardial iron overload. There was a negative correlation between myocardial MRI T2* and SF (r=-0.479, P=0.01). Myocardial MRI T2* was positively correlated with liver MRI T2* (r=0.378, P=0.047). Age was not significantly correlated with SF, LVEF, or liver MRI T2*.

CONCLUSIONMagnetic resonance imaging (T2*) detection is an effective and non-invasive means for detecting myocardial and liver iron overload in patients with β-thalassemia major receiving blood transfusion. T2* combined with SF is the main diagnostic indicator to assess iron overload in the vital organs.

Adolescent ; Adult ; Child ; Female ; Ferritins ; blood ; Humans ; Iron ; metabolism ; Iron Overload ; diagnosis ; metabolism ; pathology ; Liver ; metabolism ; Magnetic Resonance Imaging ; Male ; Myocardium ; metabolism ; Young Adult ; beta-Thalassemia ; diagnosis ; metabolism ; pathology

OBJECTIVETo investigate the mechanisms underlying bone marrow damage by iron overload in pancytopenic patients with positive BMMNC-Coombs test (IRP).

METHODSTwenty-one iron overloading, 26 non-iron overloading IRP patients and 10 normal controls were enrolled in this study. The expressions of ROS, Bcl-2, Caspase-3 and apoptosis of BMMNC were analyzed by flow cytometry (FCM). Antioxidants were added to iron overloading IRP BMMNC, and then the changes of indices above were detected by FCM. The number and apoptosis of T lymphocytes of IRP patients were also detected.

RESULTSROS and apoptosis of BMMNC, myelocytes, erythrocytes and stem cells of iron overloading IRP patients were significantly higher than that of non-iron overloading IRP ones and normal controls (P < 0.05). The expressions of Bcl-2 on BMMNC, erythrocytes and stem cells of iron overloading IRP patients were significantly lower than those of non-iron overloading IRP ones (P < 0.05). The levels of Caspase-3 on myelocytes, erythrocytes and stem cells of iron overloading IRP patients were significantly higher than those of non-iron overloading IRP ones and normal controls (P < 0.05). After treatment with antioxidants, the expressions of ROS, Caspase-3 and apoptosis of iron overloading IRP BMMNC significantly decreased, but opposite for Bcl-2. The percentages of CD4(+) lymphocytes [ ( 40.86 ± 8.74）%] and CD4(+)/CD8(+) (1.44 ± 0.36) in PB of iron overloading IRP patients were significantly higher than that of non-iron overloading IRP ones [(35.96 ± 7.03)% and 1.14 ± 0.37] and normal controls [(28.00 ± 6.73)% and 0.79 ± 0.21], respectively (P < 0.05), as opposite for CD8(+) lymphocytes (P < 0.05). The apoptosis of CD8(+) lymphocytes [(27.35 ± 10.76)%] and the ratio of CD8(+) apoptosis/CD4(+) apoptosis (2.51 ± 0.81) in BM of iron overloading IRP patients were significantly higher than those of non-iron overloading IRP ones [(15.47 ± 8.99)%] and normal controls (1.39 ± 0.47), respectively (P < 0.05). The apoptosis of erythrocytes and stem cells coated with auto-antibodies in BM of iron overloading IRP patients were significantly higher than those of non-iron overloading IRP and normal controls.

CONCLUSIONMechanisms underlying bone marrow damage by iron overload might be through the follows: ①The increased ROS induced by excessive iron deposition affected the expressions of Caspase-3 and Bcl-2, which caused more BMMNC apoptosis; ②The abnormal number and ratio of T lymphocytes caused by iron overload aggravated the abnormality of immunity of IRP; ③Iron overload may increase the damage to erythrocytes and stem cells coated with auto-antibodies.

Adolescent ; Adult ; Aged ; Bone Marrow ; pathology ; Case-Control Studies ; Caspase 3 ; metabolism ; Coombs Test ; Female ; Humans ; Iron Overload ; Male ; Middle Aged ; Pancytopenia ; immunology ; pathology ; physiopathology ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Reactive Oxygen Species ; metabolism ; Young Adult

OBJECTIVE: To explore the effect of chronic iron overload on the lesion of atherosclerosis (AS) in apolipoprotein (apo) E knockout mice. METHODS: Twenty-four ApoE knockout mice were randomly divided into ApoE knockout group (0.1 mL saline for 4 weeks) and iron overload group (10 mg iron dextran for 4 weeks). The levels of serum iron (SI), total iron binding capacity, contents of malondialdehyde (MDA), and activity of superoxide dismutase (SOD) in the liver were measured. Iron deposition in the liver and heart was determined, and atherosclerotic plaque areas of the sinus aortae were analyzed. RESULTS: In the iron overload group, the levels of SI increased by 377.86%, the saturation of transferrin increased by 121.98% and the levels of iron in the liver increased by 2,548.15% (P<0.01). The contents of MDA in the liver increased by 32.51% (P<0.01), and the activity of SOD in the liver decreased by 17.2% in the ApoE knockout group (P<0.05). The level of MDA in the liver increased by 411.15%, and the activity of SOD in the liver decreased by 46.84% in the iron overload group (P<0.01). There was a significant deposition of iron in the liver and heart of mice, and the areas of atherosclerotic plaque of sinus aortae increased markedly in the iron overload group. CONCLUSION Chronic iron overload may promote the development of AS lesion in the ApoE knockout mice, in which the increased oxidative stress and lipid oxidation may involve.
Animals ; Apolipoproteins E ; genetics ; metabolism ; Atherosclerosis ; etiology ; metabolism ; pathology ; Iron ; blood ; Iron Overload ; complications ; Male ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; metabolism ; Oxidative Stress ; Random Allocation ; Superoxide Dismutase ; metabolism ; Transferrin ; metabolism