The comparison of insulin sensitivity in non-diabetic hemodialysis patients treated with and without recombinant human erythropoietin.

BACKGROUND: Patients with end-stage renal disease (ESRD) are known to have insulin resistance. Treatment with EPO is associated with improvement in insulin sensitivity in uremic patients. The aim of this study was to compare insulin sensitivity and pancreatic B cell function in adult non-diabetic uremic hemodialysis patients treated with or without rHuEPO. SUBJECTS AND METHODS: Three groups of subjects were included to the study: hemodialysis patients treated with rHuEPO [EPO(+) group] or without rHuEPO [EPO(-) group], and healthy controls. Anthropometrical parameters, lipid levels, fasting glucose and insulin levels were measured in all subjects. Homeostasis Model Assessment (HOMA) was used to compare insulin sensitivity. ANOVA, independent t-test, and Pearson correlation were used for statistical analysis. RESULTS: Mean insulin level of control group (20.04 +/- 7.2 pmol/l) was significantly lower than EPO(+) group (p < 0.04) and EPO(-) group (p < 0.0001). HOMA-(%B) levels in the EPO(+) group were significantly lower than in the EPO(-) group (106 +/- 42, 140 +/- 63 respectively, p < 0.02). HOMA-(%B) levels in the control group (66 +/- 17) were significantly lower than in the EPO(+) and EPO(-) group (p < 0.005 and p < 0.0001 respectively). HOMA-(%S) levels in the EPO(+) groups was significantly higher than in the EPO(-) group (91 +/- 40, 56 +/- 26, respectively; p < 0.01). HOMA-(%S) levels of control group (125 +/- 24 ) was significantly higher than EPO(+) and EPO(-) groups (p < 0.02, p < 0.0001 respectively). We found a positive correlation between duration of erythropoietin treatment and insulin sensitivity (r = 0.484, p < 0.002). CONCLUSIONS: Firstly, patients treated with EPO are insulin sensitive compared to patients not treated with EPO. Secondly, duration of erythropoietin treatment is positively correlated with insulin sensitivity in hemodialysis patients.     

Single dose recombinant human erythropoietin reduces transforming growth factor beta in patients on chronic haemodialysis.

Short-term effects of recombinant human erythropoietin on serum levels of transforming growth factor beta-1, interleukin 1-alpha, interleukin 3, interferon gamma, and tumour necrosis factor alpha in patients with chronic renal failure on chronic haemodialysis were investigated. Recombinant human erythropoietin was applied subcutaneously in a dose of 75 IU/kg on 19 patients. Serum levels of transforming growth factor beta-1, interleukin 1-alpha, interleukin 3, interferon gamma, tumour necrosis factor alpha and erythropoietin, red blood cell parameters: red blood cell count, haemoglobin, haematocrit, and erythrocyte indices were determined before and after recombinant human erythropoietin single application. Transforming growth factor beta-1 serum levels were decreased after recombinant human erythropoietin (22.70 +/- 1.51 ng/ml versus 18.77 +/- 1.70 ng/ml (p < 0.01). None of the other investigated parameters was influenced significantly by recombinant human erythropoietin. Recombinant human erythropoietin in patients with chronic renal failure on chronic haemodialysis may influence anaemia not only through its stimulating effect on erythropoiesis, but also by direct oxygen-independent decrease of at least one of the negative regulators of erythropoiesis--the transforming growth factor beta.     

Modulatory effect of N-acetylcysteine on pro-antioxidant status and haematological response in healthy men

The aim of this study was to follow up whether the modification of pro-antioxidant status by 8-day oral application of N-acetylcysteine (NAC) in healthy men affects the haematological response, whether there is a direct relationship between antioxidant defences and erythropoietin (EPO) secretion and whether NAC intake enhances exercise performance. Fifteen healthy men were randomly assigned to one of two groups: control or NAC (1,200 mg d⁻¹ for 8 days prior to and 600 mg on the day of exercise trial). To measure the ergogenic effectiveness of NAC, subjects performed incremental cycle exercise until exhaustion. NAC administration significantly influenced the resting and post-exercise level of glutathione (+31%) as well as the resting activity of glutathione enzymes (glutathione reductase, −22%; glutathione peroxidase, −18%). The oxidative damage markers, i.e., protein carbonylation and lipid peroxidation products (thiobarbituric acid reactive substance) were reduced by NAC by more than 30%. NAC noticeably affected the plasma level of EPO (+26%), haemoglobin (+9%), haematocrit (+9%) and erythrocytes (−6%) at rest and after exercise. The mean corpuscular volume and the mean corpuscular haemoglobin increased by more than 12%. Plasma total thiols increased by 17% and directly correlated with EPO level (r = 0.528, P < 0.05). NAC treatment, contrary to expectations, did not significantly affect exercise performance. Our study has shown that 8-day NAC intake at a daily dose of 1,200 mg favours a pro-antioxidant status and affects haematological indices but does not enhance exercise performance.     

Development of a chemiluminescent imaging assay for the detection of anti‐erythropoietin antibody in human sera

Measuring low amounts of anti‐erythropoietin antibodies (anti‐EPO Abs) is important to evaluate the therapeutic safety of recombinant human erythropoietin (rhEPO). In this work, a simple, sensitive and high‐throughput chemiluminescent (CL) imaging assay was developed for the detection of anti‐EPO Abs in human sera. The influence of several physicochemical parameters, such as coating conditions, incubation time, detergent concentration and exposure time, were investigated. A calibration curve was established and the range of quantitative detection was 0.12–13.91 ng/mL. The limit of detection (LOD, 3σ) for the CL‐imaging assay was 0.033 ng/mL. Compared to conventional colorimetric enzyme‐linked immunosorbent assay (ELISA), the LOD of the CL‐imaging assay is 50‐fold lower. The recoveries of anti‐EPO Abs in the fortified serum were in the range 87.1–116.9% using the present method, which highlighted the validity of the CL‐imaging assay system to accurately determine the anti‐EPO Abs in serum samples. CL‐imaging assay was used to evaluate the presence of anti‐EPO Abs in serum samples obtained from chronic renal failure (CRF) patients treated with rhEPO. Contrary to what was expected, the sera from CRF patients did not contain anti‐EPO Abs. Copyright © 2008 John Wiley & Sons, Ltd.     

Biological effect of human erythropoietin in transgenic mice]

Transgenic mice were obtained inheriting the human erythropoietin gene under the control of viral regulatory elements. The reliable difference in haematocrit, the content of haemoglobin and percentage of reticulocytes in peripheral blood were not revealed. The level of serum erythropoietin in transgenic mice is several fold higher than in control mice. The increased pool of erythroid cells was observed in the bone marrow of transgenic mice, especially of normoblasts (3-fold) and reticulocytes (4,5-fold).     

全反式维甲酸对急性早幼粒细胞白血病患者血清学的影响

目的：探讨全反式维甲酸（All trans retinoic acid,ATRA）作为辅助剂在急性早幼粒细胞白血病（Acute promyelocytic leukemia, APL）治疗中,对患者血清促红细胞生成素（Erythropoietin,EPO）、血清铁蛋白、叶酸和维生素B12水平的影响。方法：回顾性分析 我院2011 年6 月-2015 年6 月接诊的50 例急性早幼粒细胞白血病患者的临床资料。根据患者的治疗方法不同将患者分为两组, A 组（亚砷酸钠治疗组）和B 组（亚砷酸钠联合ATRA）。对比两组患者治疗后血清铁蛋白、EPO、叶酸和维生素B12 恢复情况。结 果：两组患者入院时所有血清EPO、铁蛋白等比较,差异无统计学意义（P>0.05）;治疗后两组患者血清各指标均有所改善（P<0. 05）;治疗后B 组患者中EPO、血清B12、血清铁蛋白和叶酸恢复正常水平者明显多于A 组,差异具有统计学意义（P<0.05）。结论： 全反式维甲酸辅助治疗急性早幼粒细胞白血病患者能够更好的改善患者血清EPO、铁蛋白、叶酸和维生素B12 的异常,对于疾病 的治疗有一定的效果。     

Effects of SGLT2 inhibitors on haematocrit and haemoglobin levels and the associated cardiorenal benefits in T2DM patients: A meta‐analysis

To explore the effect and magnitude of effect of sodium‐glucose cotransporter‐2 (SGLT2) inhibitors on haematocrit and haemoglobin and the related cardiorenal benefits in patients with type 2 diabetes mellitus (T2DM), PubMed, Web of Science, CENTRAL and EMBASE were searched to identify eligible trials. Weighted mean differences (WMDs) with 95% confidence intervals (CIs) were calculated using a random‐effects model. Seventy‐eight studies were included in the meta‐analysis. SGLT2 inhibitors significantly increased haematocrit and haemoglobin levels compared with control (total WMD 2.27% [95% CI 2.08, 2.47] and 6.20 g/L [95% CI 5.68, 6.73], respectively). Except for dapagliflozin (p = 0.000), no notable dose‐dependent relationship was revealed for other SGLT2 inhibitors. The effect could be sustained or even slightly increased with long‐term therapy (coef. =0.009, 95% CI [0.005, 0.013], p = 0.000). In subgroup analyses, haematocrit elevation increased with higher body mass index (BMI). A greater haematocrit elevation could be observed in white patients or when compared with active controls. In conclusion, SGLT2 inhibitors increased haematocrit and haemoglobin levels in T2DM patients. Changes in haematocrit and haemoglobin seem to be surrogate markers of improvement in renal metabolic stress, and important mediators involved in cardiorenal protection.     

丁酸钠对CHO-EPO工程细胞株rhEPO表达量的影响

以稳定整合有ｐＥＤＥＰＯ的ＣＨＯＥＰＯ工程细胞株为研究对象,在无血清条件下,系统观察了０５、１０、２５和５０ｍｍｏｌ／Ｌ４个浓度的丁酸钠作用于该细胞株的情况,结果表明：丁酸钠对ＣＨＯＥＰＯ工程细胞的生长有明显的抑制作用;影响ＣＨＯＥＰＯ工程细胞ＥＰＯ表达,浓度１０ｍｍｏｌ／Ｌ可提高ＥＰＯ表达量２５倍左右,并可持续较长的一段时间;延缓ＣＨＯＥＰＯ工程细胞在无血清培养时的细胞脱落;提高ＣＨＯＥＰＯ工程细胞ＥＰＯｍＲＮＡ水平     

Treatment of anemia in patients with renal failure using erythropoietin obtained by genetic recombination

In 5 haemodialyzed patients with end-stage renal failure an effect of human recombinant erythropoietin (r-huEpo) on haemoglobin, haematocrit and iron metabolism was studied. After 12 weeks of the treatment, a significant increase in haemoglobin and haematocrit but significant decrease in plasma ferritin were noted. During r-huEpo treatment, one patients presented clinical symptoms of increased blood coagulation whereas another patients an increase in blood pressure. r-huEpo did not influence leukocytes and platelets count as well as liver function tests. Our results suggest, that r-huEpo is highly effective and safe in the treatment of anaemia in patients with chronic uraemia. Iron metabolism, blood pressure and blood coagulation must be monitored during therapy with r-huEpo.     

Induction of foetal haemoglobin synthesis in erythroid progenitor stem cells: mediated by water‐soluble components of Terminalia catappa

Current novel therapeutic agents for the treatment of sickle cell anaemia (SCA) focus on increasing foetal haemoglobin (HbF) levels in SCA patients. Unfortunately, the only approved HbF‐inducing agent, hydroxyurea, has long‐term unpredictable side effects. Studies have shown the potential of plant compounds to modulate HbF synthesis in primary erythroid progenitor stem cells. We isolated a novel HbF‐inducing Terminalia catappa distilled water active fraction (TCDWF) from Terminalia catappa leaves that induced the commitment of erythroid progenitor stem cells to the erythroid lineage and relatively higher HbF synthesis of 9.2‐ and 6.8‐fold increases in both erythropoietin (EPO)‐independent and EPO‐dependent progenitor stem cells respectively. TCDWF was differentially cytotoxic to EPO‐dependent and EPO‐independent erythroid progenitor stem cell cultures as revealed by lactate dehydrogenase release from the cells. TCDWF demonstrated a protective effect on EPO‐dependent and not EPO‐independent progenitor cells. TCDWF induced a modest increase in caspase 3 activity in EPO‐independent erythroid progenitor stem cell cultures compared with a significantly higher (P?0.05) caspase 3 activity in EPO‐dependent ones. The results demonstrate that TCDWF may hold promising HbF‐inducing compounds, which work synergistically, and suggest a dual modulatory effect on erythropoiesis inherent in this active fraction. Copyright © 2014 John Wiley & Sons, Ltd.     

慢性心力衰竭患者内源性促红细胞生成素的改变及临床意义

目的:探讨内源性促红细胞生成素(EPO)在慢性心力衰竭(CHF)及CHF贫血发病中的作用及临床价值。方法:采用放射性免疫分析法测定117例CHF患者和40例非CHF患者血浆EPO水平,分析EPO水平与心功能分级、贫血以及CHF患者预后的关系。结果:心功能II～IV患者EPO水平显著上升,与对照组比较均有显著性差异(P<0.05);EPO水平随着心功能分级增高而逐渐上升,在各级间比较有显著性差异(P<0.05);CHF伴贫血患者EPO水平随着心功能分级增高和贫血程度的加重而逐渐上升,在各级间比较有显著性差异(P<0.05);死亡组EPO水平显著高于存活组,而Hb水平显著低于存活组,相比较有显著性差异(P<0.05)。结论:CHF患者和CHF伴贫血患者内源性EPO水平升高,EPO水平的上升与CHF患者病情严重程度有关,并且是CHF患者预后不良的预测指标。     

A Biomathematical Model of Human Erythropoiesis under Erythropoietin and Chemotherapy Administration

Anaemia is a common haematologic side effect of dose-dense multi-cycle cytotoxic polychemotherapy requiring erythrocyte transfusions or erythropoietin (EPO) administration. To simulate the effectiveness of different EPO application schedules, we performed both modelling of erythropoiesis under chemotherapy and pharmacokinetic and dynamic modelling of EPO applications in the framework of a single comprehensive biomathematical model. For this purpose, a cell kinetic model of bone marrow erythropoiesis was developed that is based on a set of differential compartment equations describing proliferation and maturation of erythropoietic cell stages. The system is regulated by several feedback loops comprising those mediated by EPO. We added a model of EPO absorption after injection at different sites and a pharmacokinetic model of EPO derivatives to account for the effects of external EPO applications. Chemotherapy is modelled by a transient depletion of bone marrow cell stages. Unknown model parameters were determined by fitting the predictions of the model to data sets of circulating erythrocytes, haemoglobin, haematocrit, percentage of reticulocytes or EPO serum concentrations derived from the literature or cooperating clinical study groups. Parameter fittings resulted in a good agreement of model and data. Depending on site of injection and derivative (Alfa, Beta, Delta, Darbepoetin), nine groups of EPO applications were distinguished differing in either absorption kinetics or pharmacokinetics. Finally, eight different chemotherapy protocols were modelled. The model was validated on the basis of scenarios not used for parameter fitting. Simulations were performed to analyze the impact of EPO applications on the risk of anaemia during chemotherapy. We conclude that we established a model of erythropoiesis under chemotherapy that explains a large set of time series data under EPO and chemotherapy applications. It allows predictions regarding yet untested EPO schedules. Prospective clinical studies are needed to validate model predictions and to explore the feasibility and effectiveness of the proposed schedules.     

Antioxidant status and lipid peroxidation in hemodialysis patients undergoing erythropoietin and erythropoietin-vitamin E combined therapy.

In this study, plasma and red blood cell (RBC) antioxidant status and plasma lipid peroxidation were investigated in 46 hemodialysis patients. In addition, the effect of erythropoietin (EPO) and EPO-vitamin E combination therapy on plasma and RBC antioxidant status, and plasma lipid peroxidation were examined. There were 10 healthy subjects in the control group and 10 hemodialysis patients in the untreated group. The third group included 36 hemodialysis patients that were given EPO (100 U/kg) for 3 months, 3 times per week. The fourth group included 36 hemodialysis-patients from the EPO group that were given EPO at a 50% decreased dose + vitamin E (300 mg/day) for 3 months. MDA levels in the untreated group, the EPO group and the EPO + vitamin E groups were found to be higher than the control group (p < 0.001, in both). Furthermore, MDA levels in both of the treatment groups were lower when compared to the untreated group (p < 0.001, in both). Plasma vitamin E levels in the untreated, the EPO group and EPO + vitamin E groups were lower than the control group (p < 0. 001). In contrast, plasma vitamin E levels in the treatment groups were higher in comparison with the control group (p < 0.05). SOD activities in the untreated, the EPO group and the EPO + vitamin E groups were found to be lower than the control group (p < 0.001). SOD activities in the treatment groups were higher than the control group (p<0.001). The SOD activities in the EPO+vitamin E group increased when compared to the EPO group (p < 0.001). CAT activities in the untreated, the EPO group and the EPO + vitamin E groups were found to be lower than the control group (p < 0.001 in untreated and EPO groups, p <0.01 in EPO+ vitamin E group). CAT activities in EPO and EPO+ vitamin E groups were increased when compared to the untreated group (p < 0.01). In conclusion, our findings have shown that antioxidant status decreased and lipid peroxidation increased in hemodialysis patients. EPO has an antioxidant effect on the RBC and plasma antioxidant status, and plasma lipid peroxidation. These effects were moderately increased by the combination of vitamin E and EPO.     

Proteome analysis of serum from type 2 diabetics with nephropathy

Diabetic nephropathy (DN) is a renal disease which develops as a consequence of diabetes mellitus. Microalbuminuria is the earliest clinical sign of DN. There are no specific diagnostic biomarkers for type 2 diabetics with nephropathy other than microalbuminuria and macroalbuminuria. However, microalbuminuria does not constitute a sole independent indicator for type 2 diabetics with nephropathy, and thus, another screening method, such as a biomarker assay, is required in order to diagnose it more correctly. Therefore, we have utilized two-dimensional electrophoresis (2-DE) to identify human serum protein markers for the more specific and accurate prediction of progressive nephropathy in type 2 diabetes patients, via comparisons of the serum proteome in three experimental groups: type 2 diabetes patients without microalbuminuria (DM, n = 30), with microalbuminuria (MA, n = 29), and with chronic renal failure (CRF, n = 31). As a result, proteins which were differentially expressed with statistical significance (p < 0.05) in MA and CRF groups as compared to those in DM group were selected and identified by ESI-Q-TOF MS/MS. Among these identified proteins, two proteins which might be useful as diagnostic biomarkers of type 2 diabetics with nephropathy were verified by Western blotting: extracellular glutathione peroxidase (eGPx) and apolipoprotein (ApoE) were found to exhibit a progressive reduction in MA and CRF groups. Notably, eGPx was further verified by ELISA using DM (n = 100) and MA (n = 96) patient samples. Collectively, our results show that the two proteins identified in this study may constitute potential biomarkers for the diagnosis of type 2 diabetics with nephropathy.     

Erythropoietin stimulates the coronary collateral development in patients with coronary chronic total occlusion

Objective

Erythropoietin (EPO) improves cardiac function and induces neovascularisation in post-myocardial infarction heart failure. The aim of this study was to analyse the association between the serum erythropoietin level and coronary collateral development in patients with coronary artery disease and chronic total occlusion.

Methods

A total of 168 patients consisting of 117 with coronary artery disease (CAD, (62 with chronic total occlusion (CTO), 55 without CTO)) and 51 with healthy coronary arteries were included in the study. The patients were assigned as coronary artery disease without CTO (group 0), CAD with CTO (group 1: poor collateral development, group 2: good collateral development) and normal coronary arteries (group 3).

Results

There was a significant positive correlation between serum EPO levels and the Rentrop scores in angiography (r = 0.243, p = 0.001). Similarly, a positive correlation was found between serum EPO levels and the Syntax scores (r = 0.253, p = 0.001). Echocardiography revealed a negative correlation between serum EPO levels and the cardiac ejection fraction (r = ?0.210, p = 0.006).

Conclusions

Serum EPO is a useful biomarker for coronary collateral development in patients with CTO.

     

Delta-aminolevulinate dehydratase activity in red blood cells of rats infected with Trypanosoma evansi

The aim of this study was to evaluate the activity of delta-aminolevulinate dehydratase (δ-ALA-D) in red blood cells of rats infected with Trypanosoma evansi and establish its association with haematocrit, serum levels of iron and zinc and lipid peroxidation. Thirty-six male rats (Wistar) were divided into 2 groups with 18 animals each. Group A was non-infected while Group B was intraperitoneally infected, receiving 7·5×106 trypomastigotes per animal. Each group was divided into 3 subgroups of 6 rats and blood was collected during different periods post-infection (p.i.) as follows: day 5 (A1 and B1), day 15 (A2 and B2) and day 30 PI (A3 and B3). Blood samples were collected by cardiac puncture to estimate red blood cell parameters (RBC), δ-ALA-D activity and serum levels of iron, zinc and thiobarbituric acid reactive substances (TBARS). Rats in group B showed a significant (P<0·05) reduction of RBC count, haemoglobin concentration and haematocrit at days 5 and 15 p.i. The activity of δ-ALA-D in blood was significantly (P<0·001) increased at days 15 and 30 p.i. δ-ALA-D activity in blood had a significant (P<0·05) negative correlation with haematocrit (r=-0·61) and haemoglobin (r=-0·70) at day 15 p.i. There was a significant (P<0·05) decrease in serum iron and zinc levels and an increase in TBARS levels (P<0·05) during infection. The δ-ALA-D activity in blood was negatively correlated with the levels of iron (r=-0·68) and zinc (r=-0·57) on day 30 p.i. It was concluded that the increased activity of δ-ALA-D in blood might have occurred in response to the anaemia in remission as heme synthesis was enhanced.     

Is malarial anaemia homologous to neocytolysis after altitude acclimatisation?

Malaria patients frequently develop severe anaemia that can persist after Plasmodium infection has been cleared from the circulation. This puzzling phenomenon involves massive death of young uninfected erythrocytes at a time when parasitic infection is very low. We have observed striking similarities in erythrocyte homoeostasis during altitude acclimatisation and Plasmodium infection, both of which initially induce an increase in circulating erythropoietin (Epo). Decreasing levels of Epo after return to low altitudes induce the death of young erythrocytes, a phenomenon called neocytolysis. In a similar way, we propose that Epo, which peaks during acute malaria and decreases after parasite clearance, could be contributing to anaemia causing neocytolysis during recovery from Plasmodium infection.     

Differential effects of haloperidol and olanzapine on the expression of erythropoietin and its receptor in rat hippocampus and striatum

Compared with first-generation antipsychotics (FGAs), second-generation antipsychotics (SGAs) seem to be neuroprotective and trigger neuroplasticity. Because neuroplasticity is regulated by a variety of neurotrophic factors we studied differential effects of haloperidol (HAL, a FGA) and olanzapine (OLZ, a SGA) on temporal expression of erythropoietin (EPO), a potent neuroprotective factor and its receptor (EPOr) in rat brain. Rats (8-10/group) were treated with HAL or OLZ for 14 days (HAL-14 or OLZ-14) or 45 days (HAL-45 or OLZ-45). Animals were killed by decapitation or by perfusion to collect brains for immunoblotting and immunohistochemical analysis respectively. In hippocampus, the levels of both EPO and EPOr were significantly increased in HAL-14 (p < 0.001) and OLZ-14 (p < 0.001) groups. Their levels decreased in HAL-45 compared with levels in HAL-14 (EPO, p < 0.001; EPOr, p < 0.05), whereas the levels were further increased (EPO, p < 0.05) in OLZ-45 compared with OLZ-14. In striatum, the levels of both EPO and EPOr were unchanged in HAL-14 and EPO levels significantly decreased in HAL-45 (p < 0.05), whereas their levels were significantly increased in OLZ-14 and OLZ-45 compared with the vehicle-treated control (p < 0.001). Both EPO and EPOr were primarily expressed by neurons and endothelial cells. These data suggest that SGAs such as OLZ may have neuroprotective effects through expression of EPO that may be clinically relevant for long-term safe and beneficial management of psychotic patients.