Reactive oxygen species mediated T lymphocyte abnormalities in an iron-overloaded mouse model and iron-overloaded patients with myelodysplastic syndromes.

The adverse effects of iron overload have raised more concerns as a growing number of studies reported its association with immune disorders. This study aimed to investigate alterations in the immune system by iron overload in patients with myelodysplastic syndrome (MDS) and an iron-overloaded mouse model. The peripheral blood from patients was harvested to test the effect of iron overload on the subsets of T lymphocytes, and the level of reactive oxygen species (ROS) was also evaluated. The data showed that iron-overloaded patients had a lower percentage of CD3+ T cells and disrupted T cell subsets, concomitant with higher ROS level in lymphocytes. In order to explore the mechanism, male C57Bl/6 mice were intraperitoneally injected with iron dextran at a dose of 250 mg/kg every 3 days for 4 weeks to establish an iron-overloaded mouse model and the blood of each mouse was collected for the analysis of the T lymphocyte subsets and T cell apoptosis. The results showed that iron overload could reduce the percentage of CD3+ T cells and the ratio of Th1/Th2 and Tc1/Tc2 but increase the percentage of regulatory T (Treg) cells and the ratio of CD4/CD8. We also found that iron overload induced the apoptosis of T lymphocytes and increased its ROS level. Furthermore, these effects could be partially recovered after treating with antioxidant N-acetyl-L-cysteine (NAC) or iron chelator deferasirox (DFX). Taken together, these observations indicated that iron overload could selectively affect peripheral T lymphocytes and induce an impaired cellular immunity by increasing ROS level.

p38 MAPK Inhibitor Insufficiently Attenuates HSC Senescence Administered Long-Term after 6 Gy Total Body Irradiation in Mice.

Senescent hematopoietic stem cells (HSCs) accumulate with age and exposure to stress, such as total-body irradiation (TBI), which may cause long-term myelosuppression in the clinic. However, the methods available for long-term myelosuppression remain limited. Previous studies have demonstrated that sustained p38 mitogen-activated protein kinases (p38 MAPK) activation in HSCs following exposure to TBI in mice and the administration of its inhibitor twenty-four hours after TBI may partially prevent long-term myelosuppression. However, long-term myelosuppression is latent and identified long after the administration of radiation. In this study, we investigated the effects of SB203580 (a small molecule inhibitor of p38 MAPK) on long-term myelosuppression induced by TBI. Mice with hematopoietic injury were injected intraperitoneally with SB203580 every other day five times beginning 70 days after 6 Gy of (137)Cs γ ray TBI. Our results at 80 days demonstrated that SB203580 did not significantly improve the TBI-induced long-term reduction of peripheral blood cell and bone marrow nucleated cell (BMNC) counts, or defects in hematopoietic progenitor cells (HPCs) and HSC clonogenic function. SB203580 reduced reactive oxygen species (ROS) production and p-p38 expression; however, SB203580 had no effect on p16 expression in the HSCs of mice. In conclusion, these findings suggest that treatment with SB203580 70 days after TBI in mice inhibits the ROS-p38 oxidative stress pathway; however, it has no therapeutic effect on long-term myelosuppression induced by TBI.

[Effects of dipeptidyl peptidase-4 on the hematopoiesis and transplantation].

Dipeptidyl peptidase-4 (DPP-4) is a protease that cleaves the peptides with alanine, praline, or other selective amino acids at the N-terminal penultimate position. The substrates of DPP-4 include many chemokines, colony-stimulating factors, and interleukins. Recent research has shown that DPP-4 can affect the hematopoietic stem and progenitor cells and transplantation by truncating the granulocyte colony stimulating factor. However, its regulatory effect on DPP-4 and most peptides truncation are still unknown. This review summarizes the recent advances in the DPP-4 research.

[Establishment of an mouse model of iron-overload and its impact on bone marrow hematopoiesis].

OBJECTIVE: To establish a mouse model of iron overload by intraperitoneal injection of iron dextran and investigate the impact of iron overload on bone marrow hematopoiesis. METHODS: A total of 40 C57BL/6 mice were divided into control group, low-dose iron group (12.5 mg/ml), middle-dose iron group (25 mg/ml), and high-dose iron group (50 mg/ml). The control group received normal saline (0.2 ml), and the rest were injected with intraperitoneal iron dextran every three days for six weeks. Iron overload was confirmed by observing the bone marrow, hepatic, and splenic iron deposits and the bone marrow labile iron pool. In addition, peripheral blood and bone marrow mononuclear cells were counted and the hematopoietic function was assessed. RESULTS: Iron deposits in bone marrow, liver, and spleen were markedly increased in the mouse models. Bone marrow iron was deposited mostly within the matrix with no significant difference in expression of labile iron pool.Compared with control group, the ability of hematopoietic colony-forming in three interventional groups were decreased significantly (P<0.05). Bone marrow mononuclear cells counts showed no significant difference. The amounts of peripheral blood cells (white blood cells, red blood cells, platelets, and hemoglobin) in different iron groups showed no significant difference among these groups;although the platelets were decreased slightly in low-dose iron group [(780.7±39.60)×10(9)/L], middle dose iron group [(676.2±21.43)×10(9)/L], and high-dose iron group [(587.3±19.67)×10(9)/L] when compared with the control group [(926.0±28.23)×10(9)/L], there was no significant difference(P>0.05). CONCLUSIONS: The iron-overloaded mouse model was successfully established by intraperitoneal administration of iron dextran. Iron overload can damage the hepatic, splenic, and bone marrow hematopoietic function, although no significant difference was observed in peripheral blood count.

[The protective effects of SB203580 against mortality and radiation induced intestinal injury of mice].

This study is to investigate the protective effects of the SB203580 against radiation induced mortality and intestinal injury of mice. A total of 67 male C57BL/6 mice (20.0-22.0 g) were matched according to body weight and randomly assigned to one of three groups: control, total body irradiation exposure (IR, 7.2 Gy) only, and IR (7.2 Gy) + SB203580 (15 mg x kg(-1)). 30 days survival rate was observed in the experiment. In intestinal injury experiment, the expression levels of caspase-3, Ki67, p53 and p-p38 were assayed in the mice intestine crypts. The results showed that the 30 days survival rate was 100% (control), 0 (IR) and 40% (IR+ SB203580), separately. Compared to the IR groups, the positive cells of caspase-3, p53 and p-p38 in crypt cells decreased 33.00%, 21.78% and 34.63%, respectively. The rate of positive cells of Ki67 increased 37.96%. Significant difference was found between all of them (P < 0.01). SB203580 potently protected against radiation-induced lethal and intestinal injury in mice, and it may be a potential radio protector.

The outcomes of bariatric surgery on rheumatoid arthritis disease activity: a prospective cohort study.

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease that primarily affects the joints. Overweight and obesity can aggravate disease activity and clinical outcome in patients with RA. However, the role of bariatric surgery in inducing weight loss in the treatment of RA has not been confirmed. In this 12-month prospective cohort study, RA patients with obesity who were referred to our hospital were included. Thirty-two patients were classified into the bariatric surgery group according to the patient's decision after a comprehensive assessment of surgery indications, and 33 patients received only pharmacotherapy for RA. At the 12-month follow-up, the response rates of ACR20, ACR50 and ACR70 were 75.0% vs. 51.5%, 53.1% vs. 39.4% and 31.3% vs. 21.2% in the bariatric surgery and non-surgery groups, respectively (all p < 0.05); the mean DAS28-ESR, DAS28-CRP and cDAI scores were 1.5 ± 0.9 vs. 2.4 ± 1.4, 1.2 ± 0.9 vs. 2.2 ± 1.7 and 9.5 ± 6.8 vs. 15.8 ± 12.5, respectively, in surgical patients compared to non-surgical patients (all p < 0.05). Compared to baseline, after 12 months, a significant reduction was observed in the use of leflunomide, biological agents, combination treatments, and NSAIDs in both groups (p < 0.05 or p < 0.01). However, there was no difference in medication use between the 2 groups either at baseline or at the 12-month follow-up (all p > 0.05). Compared to non-surgical patients, in RA patients with obesity, weight loss after bariatric surgery was associated with lower disease activity. Medication tapering for RA in patients who underwent bariatric surgery was not superior to that in non-surgical patients.

Yi-qi-yang-yin-tang increases the sensitivity of KG1a leukemia stem cells to daunorubicin by promoting cell cycle progression and regulating the expression of PTEN, TOPOII and mTOR.

The present study aimed to investigate the effects of serum containing a combination of yi-qi-yang-yin-tang (YQYYT) and daunorubicin (DNR) on multidrug resistance in KG1a leukemia stem cells (LSCs). The effects of YQYYT and DNR on proliferation, cell cycle progression and the expression of phosphatase and tensin homolog (PTEN), topoisomerase II (Topo II) and mechanistic target of rapamycin (mTOR) in KG1a cells were investigated in vitro using cell counting kit-8 assay, flow cytometry, reverse transcription-quantitative polymerase chain reaction and western blotting, respectively. It was revealed that YQYYT-containing serum did not affect proliferation of KG1a cells compared with the blank group. Furthermore, there were no significant differences on the inhibition of proliferation among different groups at various concentrations of YQYYT. Treatment with YQYYT-containing serum (volume, 20 and 40 µl) and DNR was able to significantly inhibit the proliferation of KG1a cells compared with the blank group. The inhibition rate in the treatment group with YQYYT-containing serum (40 µl) and DNR for 48 h (72.5%) was higher compared with treatment for 24 h (60.4%, P<0.01). Treatment with YQYYT-containing serum was able to promote G0 phase of KG1a cells into cell cycle in a dose- and time-dependent manner, and significantly upregulated the mRNA expression of PTEN and Topo II, but did not affect mTOR expression compared with the blank group. Treatment with serum containing YQYYT alone did not directly affect the proliferation of KG1a cells, but when the cells were treated with a combination of YQYYT-containing serum and DNR, the proliferation of KG1a cells was significantly inhibited in a dose- and time-dependent manner. Furthermore, treatment with YQYYT-containing serum was able to promote cell cycle progression of KG1a cells in the G0 phase and upregulate the expression of the negative regulatory genes PTEN and Topo II. These results indicated the potential of YQYYT to reverse multidrug resistance in LSCs.

[Follicular Helper T Cells and Expression of PD-1 in Mice with Myelodysplastic Syndrome].

OBJECTIVE: To investigate the complete blood count, morphological changes, follicular T helper (Tfh) cells and expression of PD-1 in bone marrow and spleen of mice with myelodysplastic syndrome(MDS) and to explore their significance in pathogenesis of MDS. METHODS: The 10 male NUP98-HOXD13 transgenic mice and 10 male homologous wild-type C57BL/6J mice were used for experments. The complete blood count, morphological change of NUP98-HOXD13 transgenic mice and wild-type C57BL/6J were detected by routine methods. The level of Tfh cells and expression of PD-1 in bone marrow and spleen were measured by flow cytometry. The PD-1 mRNA of bone marrow mononuclear cells and spleen cells were analyzed by real-time PCR method. RESULTS: The counts of RBC, neutrophile and platelet in above- mentioned transgenic mice were less than that in wild type C57BL/6J mice. As compared with wild type C57BL/6J mice, the morphology of RBC and platelet in transgenic mice was some abnormal, including bi-nucleated erythrocytes, ringed mucleated neutrophil and erythroblastic islands. The count of Tfh cells in transgenic mice was less than that in wild type mice, but the expression of PD-1 was higher. The expression of BMMNC PD-1 mRNA was obviously higher than that in wild type mice. CONCLUSION: The pancytopenia and dysplasia, decrease of Tfh cells and increase of PD-1 expression have been observed in NUP98-HOXD13 transgenic mice, which may be one of important reasons for promoting malignant clone and leading to impair anti immune respones.

Identification of specific gene modules in mouse lung tissue exposed to cigarette smoke.

BACKGROUND: Exposure to cigarette may affect human health and increase risk of a wide range of diseases including pulmonary diseases, such as chronic obstructive pulmonary disease (COPD), asthma, lung fibrosis and lung cancer. However, the molecular mechanisms of pathogenesis induced by cigarettes still remain obscure even with extensive studies. With systemic view, we attempted to identify the specific gene modules that might relate to injury caused by cigarette smoke and identify hub genes for potential therapeutic targets or biomarkers from specific gene modules. MATERIALS AND METHODS: The dataset GSE18344 was downloaded from the Gene Expression Omnibus (GEO) and divided into mouse cigarette smoke exposure and control groups. Subsequently, weighted gene co-expression network analysis (WGCNA) was used to construct a gene co-expression network for each group and detected specific gene modules of cigarette smoke exposure by comparison. RESULTS: A total of ten specific gene modules were identified only in the cigarette smoke exposure group but not in the control group. Seven hub genes were identified as well, including Fip1l1, Anp32a, Acsl4, Evl, Sdc1, Arap3 and Cd52. CONCLUSIONS: Specific gene modules may provide better understanding of molecular mechanisms, and hub genes are potential candidates of therapeutic targets that may possible improve development of novel treatment approaches.

[Effects of D-methionine on the hematopoietic system injury in irradiated mice].

The aim of this study was to investigate the effects of D-methionine (D-met) on the hematopoietic system injury in irradiated mice. C57BL/6 mice were divided into control group, irradiated group, 300 mg/kg D-met plus irradiation group and 1000 mg/kg D-met plus irradiation group. The control mice received sham irradiation, and the mice in remainder groups were exposed to 7.5 Gy; 1,4,8 Gy and 1 Gy of (137)Cs γ-ray respectively, were used to detect the survival rate, survival rate of bone marrow cells, WBC and its differential counts as well the colony formation ability in irradiated mice, respectively. The D-met was intraperitoneally injected to mice at 30 min before irradiation. The results showed that 300 and 1000 mg/kd D-met did not obviously enhance the survival rate of mice exposed to 7.5 Gy; the 10(-2),10(-3),10(-4) mol/L D-met significantly increased the survival rate of bone marrow cells in mice exposed to 1,4,8 Gy; 300 and 1000 mg/kg D-met even so increased the WBC count of peripheral blood in mice exposed to 1 Gy, but there was no statistical difference as compared with irradiated alone mice, moreover 300 and 1000 mg/kg D-met could obviously promote the colony formation ability of bone marrow cells in irradiated mice, the CFU-GM count was higher than that in 1 Gy irradiated mice (P < 0.05). It is concluded that the D-met can effectively mitigate the marrow cell injury resulted from irradiation, enhance the survival rate of bone marrow cells in irradiated mice, promote the recovery of hematopoietic function from radiation injury in mice.

Increased miRNA-22 expression sensitizes esophageal squamous cell carcinoma to irradiation.

miRNA-22 was previously reported to be a tumor suppressor. The aim of this study was to explore the expression and function of miRNA-22 in esophageal squamous cell carcinoma (ESCC). Expression of miRNA-22 in 100 ESCC tissues was examined by q-PCR. The correlation between miRNA-22 level and clinicopathological features was analyzed using SPSS16.0 statistical software. Moreover, the effect of miRNA-22 expression on radiosensitivity of ESCC cells was examined. miRNA-22 expression decreased in ESCC tissues, and statistical analyses showed that the expression of miRNA-22 was associated with the stage of clinical classification. No correlation was found between miRNA-22 expression and the overall survival of ESCC patients. However, significant positive correlation was found between miRNA-22 expression and the survival of patients who received radiotherapy (P < 0.05). Increased expression of miRNA-22 sensitized ESCC cells to γ-ray radiation and promoted the apoptosis of ESCC cells induced by γ-ray radiation. Increased expression level of miRNA-22 had effects on Rad51 expression after irradiation. These results demonstrate for the first time that decreased miRNA-22 expression correlates with increased radiotherapy resistance of ESCC, and that this effect is mediated, at least in part, by the Rad51 pathway.

The expression and function of miRNA-451 in non-small cell lung cancer.

miRNAs are small, non-coding RNAs that negatively regulate gene expression at the post-transcriptional and translational levels. miRNA-451 was previously reported to be down-regulated in gastric and colorectal cancers. Here, we showed that miRNA-451 expression decreased in non-small cell lung cancer (NSCLC) tissues and that its expression was negatively associated with lymph node metastasis, the stage of TNM classification and poor prognosis of NSCLC patients. Moreover, significantly different miRNA-451 expression levels were found between smoking and non-smoking patients. The overexpression of miRNA-451 inhibited cell cycle progression, cellular migration and the invasive ability of NSCLC cells. Increased miRNA-451 expression also promoted anoikis of NSCLC cells. Together, these data suggested that aberrantly expressed miRNA-451 may be associated with the development of NSCLC.

Expression and function of miRNA in postoperative radiotherapy sensitive and resistant patients of non-small cell lung cancer.

PURPOSE: To investigate the different miRNA expression profiles of postoperative radiotherapy sensitive and resistant patients of non-small cell lung cancer, explore their potential role and find some radio-sensitivity markers. MATERIALS AND METHODS: Thirty non-small cell lung cancer patients who have been treated by postoperative radiotherapy were selected and were divided into radiotherapy sensitive group and resistant group according to overall survival and local or distant recurrence rate. Expression profile of miRNA in these two groups was detected by a microarray assay and the results were validated by quantitative RT-PCR and Northern blot. At the molecular level, the effect of one differently expressed miRNA (miR-126) on the growth and apoptosis of SK-MES-1 cells induced by irradiation was examined. RESULTS: Comparing with resistant patients, five miRNAs (miRNA-126, miRNA-let-7a, miRNA-495, miRNA-451 and miRNA-128b) were significantly upregulated and seven miRNAs (miRNA-130a, miRNA-106b, miRNA-19b, miRNA-22, miRNA-15b, miRNA-17-5p and miRNA-21) were greatly downregulated in radiotherapy sensitive group. Overexpression of miRNA-126 inhibited the growth of SK-MES-1 cells and promoted its apoptosis induced by irradiation. The expression level of p-Akt decreased in miRNA-126 overexpression group. After treating with phosphoinositidyl-3 kinase (PI3K) constitutively activator (IGF-1) and inhibitor (LY294002), miRNA-126 overexpression had no significant effects on the apoptosis of SK-MES-1 cells. CONCLUSION: We found 12 differently expressed miRNAs in the radiotherapy sensitive and resistant non-small cell lung cancer samples. Moreover, our results showed miRNA-126 promoted non-small cell lung cancer cells apoptosis induced by irradiation through the PI3K-Akt pathway.

Expression of miRNA-130a in nonsmall cell lung cancer.

MicroRNAs are short regulatory RNAs that negatively modulate gene expression at the posttranscriptional level and are deeply involved in the pathogenesis of several types of cancer. The miRNA-130a has been shown to play a role in antagonizing the inhibitory effects of GAX on endothelial cell proliferation, migration and tube formation, and antagonizing the inhibitory effects of HoxA5 on tube formation in vitro. Here the authors show, for the first time, that miRNA-130a expression is increased in nonsmall cell lung cancer (NSCLC) tissues. Statistical analysis showed that overexpression of miRNA-130a was strongly associated with lymph node metastasis, stage of tumor node metastasis classification and poor prognosis. Moreover, there was a significant difference in miRNA-130a expression levels between smoking and nonsmoking patients. Multivariate Cox regression analysis showed that miRNA-130a was an independent prognostic factor for patients with NSCLC. Together, these data suggest that miRNA-130a may comprise a potential novel prognostic marker for this disease.