Injections Of rHuEPO Research Articles

Assessment of myeloid response and iron status among Sudanese pediatric ESKD on hemodialysis through reticulocyte parameters and β-globin mRNA expression

BackgroundSudanese children with End-Stage Kidney Disease (ESKD) often show limited improvement in hemoglobin levels despite treatment with recombinant human erythropoietin (rHuEPO). This study aims to assess the response to rHuEPO therapy by analyzing β-globin mRNA expression and reticulocyte parameters. Additionally, it classifies anemia among Sudanese pediatric patients based on iron status, considering age and gender as biological markers for evaluating treatment response.MethodsA prospective observational cohort study was conducted from January 2019 to February 2020 in Khartoum, Sudan, involving 45 anemic children aged 2 to 15 years diagnosed with ESKD. The treatment protocol included rHuEPO injections and maintenance hemodialysis. Laboratory assessments consisted of complete blood count (CBC), absolute reticulocyte count, ferritin, and transferrin measurements. β-globin mRNA expression was quantified using reverse transcription polymerase chain reaction (RT-PCR), and reticulocyte parameters, including Reticulocyte Hemoglobin Content (CHr), percentage of hypochromic reticulocytes (HYPO%), and Immature Reticulocyte Fraction (IRF), were measured via flow cytometry.ResultsSignificant variations in hemoglobin levels were observed across different age groups (p = 0.011). Gender analysis revealed a significant association with IRF, showing a lower IRF in male patients (p = 0.017). However, there were no significant differences in hemoglobin levels between genders (p = 0.999). β-globin mRNA expression showed considerable variability, with a strong positive correlation with hemoglobin levels (r = 0.875, p < 0.0001).ConclusionAge and gender significantly influence treatment responses in children with ESKD, highlighting the need to consider growth physiology in anemia management. This study underscores the variability in β-globin mRNA expression and its association with Flow Cytometry parameters, demonstrating their effectiveness in evaluating iron status and guiding rHuEPO dosage.

Early erythroferrone levels can predict the long-term haemoglobin responses to erythropoiesis-stimulating agents.

Our previous study reported that erythroferrone (ERFE), a newly identified hormone produced by erythroblasts, responded to recombinant human erythropoietin (rHuEPO) sensitively but its dynamics was complicated by double peaks and circadian rhythm. This study intends to elucidate the underlying mechanisms for the double peaks of ERFE dynamics and further determine whether early ERFE measurements can predict haemoglobin responses to rHuEPO. By using the purified recombinant rat ERFE protein and investigating its deposition in rats, the production of ERFE was deconvoluted. To explore the role of iron in ERFE production, we monitored short-term changes of iron status after injection of rHuEPO or deferiprone. Pharmacokinetic/pharmacodynamic (PK/PD) modelling was used to confirm the mechanisms and examine the predictive ability of ERFE for long-term haemoglobin responses. The rRatERFE protein was successfully purified. The production of ERFE was deconvoluted and showed two independent peaks (2 and 8 h). Transient iron decrease was observed at 4 h after rHuEPO injection and deferiprone induced significant increases of ERFE. Based on this mechanism, the PK/PD model could characterize the complex dynamics of ERFE. In addition, the model predictions further revealed a stronger correlation between ERFE and haemoglobin peak values than that for observed values. The complex dynamics of ERFE should be composited by an immediate release and transient iron deficiency-mediated secondary production of ERFE. The early peak values of ERFE, which occur within a few hours, can predict haemoglobin responses several weeks after ESA treatment.

Does Hypoxia and Stress Erythropoiesis Compromise Cardiac Function in Healthy Adults? A Randomized Trial

ObjectivesTo investigate whether recombinant human erythropoietin (rHuEPO) injections during an altitude training camp impact heart function.MethodsThirty (12 women) moderately trained subjects stayed at 2320 m altitude for 4 weeks while training. Subjects were randomized to placebo (isotonic saline) or rHuEPO (20 IU/kg body weight) i.v. injections. Transthoracic echocardiography imaging was acquired 3 days after arrival to altitude and prior to the first placebo or rHuEPO injection as well as one day after the last rHuEPO injection three weeks later.ResultsrHuEPO did not alter cardiovascular morphology parameters, systolic or diastolic function. In the placebo group, altitude exposure improved left ventricle (LV) systolic function due to an increased twist angle but rHuEPO had no additional effects. Pulmonary arterial systolic pressure was unaffected in either group. Notably, rHuEPO hampered LV untwist rate without affecting LV early filling.ConclusionrHuEPO provided during mild altitude exposure does not cause any major effects on heart function. The observed alteration in LV untwist induced by rHuEPO is unlikely to have a meaningful clinical effect.Trial Registration Registered on www.clinicaltrials.gov (NCT04227665).

Acute erythropoietin injection increases muscle mitochondrial respiratory capacity in young men: a double-blinded randomized crossover trial.

The aim was to investigate if acute recombinant human erythropoietin (rHuEPO) injection had an effect on mitochondrial function and if exercise would have an additive effect. Furthermore, to investigate if in vitro incubation with rHuEPO had an effect on muscle mitochondrial respiratory capacity. Eight healthy young men were recruited for this double-blinded randomized placebo-controlled crossover study. rHuEPO (400 IU/kg body wt) or saline injection was given intravenously, before an acute bout of exercise. Resting metabolic rate and fat oxidation were measured. Biopsies were obtained at baseline, 120 min after injection, and right after the acute exercise bout. Mitochondrial function (mitochondrial respiration and H2O2 emission) was measured in permeabilized skeletal muscle using high-resolution respirometry and fluorometry. Specific gene expression and enzyme activity were measured. Skeletal muscle mitochondrial respiratory capacity was measured with and without incubation with rHuEPO. Fat oxidation at rest increased after rHuEPO injection, but no difference was found in fat oxidation during exercise. Mitochondrial respiratory capacity was increased after rHuEPO injection when pyruvate was in the assay, which was not the case when saline was injected. No changes were seen in H2O2 emission after rHuEPO injection or acute exercise. Incubation of skeletal muscle fibers in vitro with rHuEPO increased mitochondrial respiratory capacity. Acute rHuEPO injection increased mitochondrial respiratory capacity when pyruvate was used in the assay. No statistical difference was found in H2O2 emission capacity, although a numerical increase was seen after rHuEPO injection. In vitro incubation of the skeletal muscle sample with rHuEPO increases mitochondrial respiratory capacity.NEW & NOTEWORTHY The effect of an acute rHuEPO injection on skeletal muscle mitochondrial function was investigated in young healthy male subjects. rHuEPO has an acute effect on skeletal muscle mitochondrial respiratory capacity in humans, where an increased mitochondrial respiratory capacity was seen. This could be the first step leading to increased mitochondrial biogenesis.

Does subcutaneous administration of recombinant human erythropoietin increase thrombotic events in total hip arthroplasty? A prospective thrombelastography analysis

BackgroundAnemia is one of severe complications in the perioperative period of total hip arthroplasty (THA). Erythropoietin (EPO) has been considered to improve patients’ anemia state, but its efficiency and safety remains controversial.MethodsA total of 152 patients who underwent total hip arthroplasty from January 2017 to March 2019 were randomized to 2 groups. Recombinant human erythropoietin (rHu-EPO) group was treated with rHu-EPO subcutaneous injection 10000 IU after operation and once daily in the next week, while control group was treated with none extra treatment. Routine hematologic examination and thrombelastography (TEG) performed at different time point respectively. Doppler ultrasound for bilateral lower limbs was performed 1 day before surgery and 7 days after surgery. Auxiliary examination outcomes, blood transfusions outcomes, and postoperative complications were recorded as assessment indicators.ResultsThe difference in the relevant indexes of traditional coagulation and TEG values between two groups were not significantly. No significant difference was observed in the incidence of thromboembolism events and other complications between two groups during postoperative period. The amount of intraoperative blood loss was similar between the two groups. However, the postoperative use and dosage of allogeneic blood in the rHu-EPO group were lower than those in the control group. The hemoglobin and hematocrit level in the rHu-EPO group were higher than that in the control group after surgery.ConclusionPostoperative subcutaneous injection of rHu-EPO can improve hematological anemia-related parameters, reduce the use and dosage of allogeneic blood transfusions (ABTs), and has no significant influence on the formation of thrombosis and other complications in patients undergoing total hip arthroplasty in short term.

Additive effect of erythropoietin use on exercise-induced endothelial activation and hypercoagulability in athletes

PurposeRecombinant human erythropoietin (rHuEPO) is known to increase thrombotic risk in patients and might have similar effects in athletes abusing the drug. rHuEPO is prohibited by anti-doping legislation, but this risk has not been investigated thoroughly. This analysis was designed to evaluate whether rHuEPO impacts hemostatic profile and endothelial and platelet activation markers in trained subjects, and whether the combination with exercise affects exercise induced alterations.MethodsThis double-blind, randomized, placebo-controlled trial enrolled healthy, trained male cyclists aged 18–50 years. Participants were randomly allocated (1:1) to receive subcutaneous injections of rHuEPO (epoetin-β; mean dose 6000 IU per week) or placebo (0.9% NaCl) for 8 weeks. Subjects performed five maximal exercise tests and a road race, coagulation and endothelial/platelet markers were measured at rest and directly after each exercise effort.ResultsrHuEPO increased P-selectin (+ 7.8% (1.5–14.5), p = 0.02) and E-selectin (+ 8.6% (2.0–15.7), p = 0.01) levels at rest. Maximal exercise tests significantly influenced all measured coagulation and endothelial/platelet markers, and in the rHuEPO group maximal exercise tests led to 15.3% ((7.0–24.3%), p = 0.0004) higher E-selectin and 32.1% ((4.6–66.8%), p = 0.0207) higher Platelet factor 4 (PF4) levels compared to the placebo group.ConclusionIn conclusion, rHuEPO treatment resulted in elevated E- and P-selectin levels in trained cyclists, indicating enhanced endothelial activation and/or platelet reactivity. Exercise itself induces hypercoagulability, and the combination of rHuEPO and exercise increased E-selectin and PF4 levels more than either intervention alone. Based on this, exercise potentially increases thrombotic risk, a risk that might be enhanced in combination with rHuEPO use.

Effects of EPO on Blood Parameters and Running Performance in Kenyan Athletes

Recombinant human erythropoietin (rHuEpo) administration enhances oxygen carrying capacity and performance at sea level. It remains unknown whether similar effects would be observed in chronic altitude-adapted endurance runners. The aim of this study was to assess the effects of rHuEpo on hematological and performance parameters in chronic altitude-adapted endurance runners as compared to sea level athletes. Twenty well-trained Kenyan endurance runners (KEN) living and training at approximately 2150 m received rHuEpo injections of 50 IU·kg body mass every 2 d for 4 wk and responses compared with another cohort (SCO) that underwent an identical protocol at sea level. Blood samples were obtained at baseline, during rHuEpo administration and 4 wk after the final injection. A maximal oxygen uptake (V˙O2max) test and 3000-m time trial was performed before, immediately after and 4 wk after the final rHuEpo injection. Hematocrit (HCT) and hemoglobin concentration (HGB) were higher in KEN compared to SCO before rHuEpo but similar at the end of administration. Before rHuEpo administration, KEN had higher V˙O2max and faster time trial performance compared to SCO. After rHuEpo administration, there was a similar increase in V˙O2max and time trial performance in both cohorts; most effects of rHuEpo were maintained 4 wk after the final rHuEpo injection in both cohorts. Four weeks of rHuEpo increased the HGB and HCT of Kenyan endurance runners to a lesser extent than in SCO (~17% vs ~10%, respectively) and these alterations were associated with similar improvements in running performance immediately after the rHuEpo administration (~5%) and 4 wk after rHuEpo (~3%).

The Performance Effects of Microdose Recombinant Human Erythropoietin Administration and Carbon Monoxide Rebreathing.

Frequent, low doses of recombinant human erythropoietin (rHuEpo) have been shown to increase the oxygen carrying capacity of an athlete and enhance endurance performance, although its effect on repeated sprint ability (RSA) remains unknown. If the mechanisms behind improved RSA performance reside within the augmented O2 carrying capacity, then carbon monoxide (CO) inhalation should inhibit RSA. Purpose: The aim of this study was to assess the effects on maximal oxygen uptake (V˙O2max) and RSA of two interventions known to differentially influence blood oxygen carrying capacity. Methods: Fourteen endurance-trained individuals were administered microdoses of rHuEpo (20-40 IUkg) or placebo twice per week for 7 wk using a randomized, crossover design. V˙O2max and RSA were measured at baseline and after rHuEpo administration. Total hemoglobin mass (tHb-mass) was measured twice at baseline (14 and 7 d before the first injection), three times during rHuEpo administration (10, 24, and 38 d after the first rHuEpo injection) and twice after the cessation of rHuEpo administration (7 and 21 d after the final injection) using the optimized CO rebreathing method. V˙O2max and RSA also were assessed in a separate cohort of 11.

Effects of erythropoietin for precaution of steroid-induced femoral head necrosis in rats

BackgroundSteroids such as glucocorticoid have been widely used for their excellent anti-inflammatory, anti-immune, and anti-shock properties. However, the long-term use in high doses has been found to cause necrosis of femoral head and other serious adverse reactions. Thus, it is of great importance to safely use these medications on patients without inducing bone necrosis.MethodsIn this preclinical study, we examined the effects of erythropoietin (EPO) to attenuate the induction of steroid-induced femoral bone necrosis using rats to build up the in-vivo models. Rats were randomly divided into three groups: negative control group (group A), disease group (group B), and EPO group (group C). 20 mg/kg methylprednisolone was administrated into group B and group C for 6 weeks with two intramuscular injections per week per rat. Group C was further given daily intraperitoneal injections of rHuEPO during this period. Group A received only injection of saline at the same schedule. 12 weeks after the initial drug administration, the rats’ femoral tissues were harvested for HE staining, immunohistochemistry studies for PECAM-1(also CD31) expression and Western Blotting for VEGF expression.ResultsHistology studies showed that compared with the disease group, EPO group had significant improvement and bone morphology being much closer to the negative control group. Immunohistochemical studies revealed that EPO group had statistically much more expression of PECAM-1 than the other groups did. Western Blot demonstrated that the EPO group had significantly higher VEGF expression than the disease group.ConclusionResults suggested that simultaneous injection of EPO could partially prevent steroid-induced ANFH.

Effects of erythropoietin on cycling performance of well trained cyclists: a double-blind, randomised, placebo-controlled trial

Substances that potentially enhance performance (eg, recombinant human erythropoietin [rHuEPO]) are considered doping and are therefore forbidden in sports; however, the scientific evidence behind doping is frequently weak. We aimed to determine the effects of rHuEPO treatment in well trained cyclists on maximal, submaximal, and race performance and on safety, and to present a model clinical study for doping research on other substances. We did this double-blind, randomised, placebo-controlled trial at the Centre for Human Drug Research in Leiden (Netherlands). We enrolled healthy, well trained but non-professional male cyclists aged 18-50 years and randomly allocated (1:1) them to receive abdominal subcutaneous injections of rHuEPO (epoetin β; mean dose 6000 IU per week) or placebo (0·9% NaCl) for 8 weeks. Randomisation was stratified by age groups (18-34 years and 35-50 years), with a code generated by a statistician who was not masked to the study. The primary outcome was exercise performance, measured as maximal power output (Pmax), maximal oxygen consumption VO2 max, and gross efficiency in maximal exercise tests with 25 W increments per 5 min, as lactate threshold and ventilatory threshold 1 (VT1) and 2 (VT2) at submaximal levels during the maximal exercise test, and as mean power, VO2, and heart rate in the submaximal exercise tests at the highest mean power output for 45 min in a laboratory setting and in a race to the Mont Ventoux (France) summit, using intention-to-treat analyses. The trial is registered with the Dutch Trial Registry (Nederlands Trial Register), number NTR5643. Between March 7, 2016, and April 13, 2016, we randomly assigned 48 participants to the rHuEPO group (n=24) or the placebo group (n=24). Mean haemoglobin concentration (9·6 mmol/L vs 9·0 mmol/L [estimated difference 0·6, 95% CI 0·4 to 0·8]) and maximal power output (351·55 W vs 341·23 W [10·32, 3·47 to 17·17]), and VO2 max (60·121 mL/min per kg vs 57·415 mL/min per kg [2·707, 0·911 to 4·503]) in a maximal exercise test were higher in the rHuEPO group compared with the placebo group. Submaximal exercise test parameters mean power output (283·18 W vs 277·28 W [5·90, -0·87 to 12·67]) and VO2 (50·288 mL/min per kg vs 49·642 mL/min per kg [0·646, -1·307 to 2·600]) at day 46, and Mont Ventoux race times (1 h 40 min 32 s vs 1 h 40 min 15 s [0·3%, -8·3 to 9·6]) did not differ between groups. All adverse events were grade 1-2 and were similar between both groups. No events of grade 3 or worse were observed. Although rHuEPO treatment improved a laboratory test of maximal exercise, the more clinically relevant submaximal exercise test performance and road race performance were not affected. This study shows that clinical studies with doping substances can be done adequately and safely and are relevant in determining effects of alleged performance-enhancing drugs. Centre for Human Drug Research, Leiden.

Protective effects of BMSCs in combination with erythropoietin in bronchopulmonary dysplasia-induced lung injury.

Bronchopulmonary dysplasia (BPD) is the most common type of chronic lung disease in infancy, for which no effective therapy is currently available. The aim of the present study was to investigate the effect of treatment with bone marrow mesenchymal stem cells (BMSCs) in combination with recombinant human erythropoietin (rHuEPO) on BPD‑induced mouse lung injury, and discuss the underlying mechanism. The BPD model was established by the exposure of neonatal mice to continuous high oxygen exposure for 14days, following which 1x106 BMSCs and 5,000U/kgrHuEPO were injected into the mice 1h prior to and 7days following exposure to hyperoxia. The animals received four treatments in total (n=10 in each group). After 14days, the body weights, airway structure, and levels of matrix metalloproteinase‑9 (MMP‑9) and vascular endothelial growth factor (VEGF) were detected using histological and immunohistochemical analyses. The effect on cell differentiation was observed by examining the presence of platelet endothelial cell adhesion molecule (PECAM) and VEGF using immunofluorescence. Compared with the administration of BMSCs alone, the body weight, airway structure, and the levels of MMP‑9 and VEGF were significantly improved in the BMSCs/rHuEPO group. The results of the present study demonstrated that the intravenous injection of BMSCs significantly improved lung damage in the hyperoxia‑exposed neonatal mouse model. Furthermore, the injection of BMSCs in combination with intraperitoneal injection of rHuEPO had a more marked effect, compared with BMSCs alone, and the mechanism may be mediated by the promoting effects of BMSCs and EPO. The results of the present study provided information, which may assist in future clinical trials.

Poster Presentations

Administration of recombinant human erythropoietin (rHuEpo) improves performance and hence is subject to abuse by athletes. The detection of rHuEpo doping remains a major challenge at present. The aim of the current study was to investigate whether circulating microRNA (miRNA) can be used for detecting r-HuEpo doping. Twenty trained males received rHuEpo injections of 50 IU∙kg -1 body mass every two days for 4 weeks. Blood was obtained 2 weeks before, during and 4 weeks after administration. For this pilot analysis, plasma miRNA expression was assessed at selected time points using the Affymetrix GeneChip 3.0 and the miScript 384 HC PCR Array (Qiagen). For the Affymetrix microarray data, GC content adjustment was carried out prior to background correction and quantile normalization. For the Qiagen PCR Array data, raw CT values exported from the RQ manager were firstly normalized to the spike-in control (i.e. cel-miR-39-3p), then to the mean of commonly expressed miRNAs with a CT < 35 prior to formal analysis. 1733 human miRNAs are present on the GeneChip 3.0. Eighty-two of the 1733 miRNAs were commonly expressed across all samples and 773 miRNAs were found in at least one sample. Six miRNAs showed significant fold changes following r-HuEpo, with 5 miRNAs up-regulated (fold change ranging from 2.03-3.07, P < 0.05) and 1 miRNA down-regulated (fold change: 2.56, P = 0.042). Out of 372 human miRNAs present (Qiagen), 205 human miRNAs were detected in all samples and 164 miRNAs were found in at least one sample. Two miRNAs were differentially expressed (fold changes: 3.4 - 3.84, P ≤ 0.03) following r-HuEpo. For significantly expressed miRNAs identified by both methods, 6 common miRNAs were found to be either predicted or validated miRNAs potentially involved in Epo signalling pathways. Analysis of identified miRNAs in the remaining samples will be required in order to determine whether circulating miRNAs can be effectively used for r-HuEpo doping detection. miRNAs isolated from red blood cells before and after r-HuEpo are also currently being analysed using next generation sequencing.

Detecting doping use: more than an analytical problem

The recent Armstrong case, where more than 250 negative doping tests are confronted with the athlete’s confession of erythropoietin use, blood doping, steroid, and growth hormone abuse, illustrates the limitations of current laboratory tests in detecting doping in sport. Despite numerous doping controls and simultaneous indications of common doping abuse among professional athletes in the last two decades, the number of positive urine tests for recombinant human erythropoietin (rHuEPO) remains remarkably low. Athletes are using various masking strategies, among them protease inhibitors, intravenous injections of rHuEPO and alternative erythropoiesis stimulating agents. As one of the countermeasures, the Athlete’s Biological Passport has been introduced. The sensitivity of the Athlete’s Biological Passport is limited if the effect of a low-dose doping remains within the intra-individual reference range. A possible solution could be the use of a novel Epo test (MAIIA Diagnostics). Another performance-enhancing strategy is the return to ‘old’ doping techniques, such as autologous blood transfusions. Several indirect methods to detect autologous blood transfusions have been proposed with the majority relying on changes in erythropoiesis-sensitive blood markers. Currently, an algorithm based on the haemoglobin (Hb) level concentration and the percentage of reticulocytes (OFF-hr model; Hb(g/l)–60·√%ret) is approved by the World Anti-Doping Agency. Genetic factors have been identified which may interfere with test interpretation. A large inter- and intra-ethnic variation in testosterone glucuronidation and excretion has been described. Consideration of genetic variation should improve performance of the testosterone doping test. Taking into account the pre-analytical care and better tailoring of the threshold values could increase test sensitivity. Anti-doping laboratories should routinely adjust for multiple testing as failure of doping control to detect cheaters could lead to more frequent controls. Finally, despite the huge technological progress, there is a need for increased collaboration between physiologists, analytical chemists, biostatisticians, and ethicists to reduce doping in sport.

Prevalence and related factors of the absence of anemia among Chinese chronic hemodialysis patients: a multicenter cross-sectional study

Some chronic hemodialysis (HD) patients can maintain normal hemoglobin levels without requiring erythropoiesis-stimulating agents (ESAs). However, the prevalence and the factors associated with this condition in Chinese chronic HD patients have not been reported. The aim of this study was to investigate clinical features, iron metabolism, and other characteristics to survey the prevalence rate and the related factors of this condition among Chinese chronic HD patients. A total of 1,318 chronic HD patients participated in this study. The patients were classified into a non-ESA group (n = 11) and an ESA group (n = 1,307). The r-HuEPO-independent (non-ESA) HD patients were defined as having hemoglobin greater than 12 g/dl for more than 6 months without r-HuEPO injection, blood transfusion, or androgen therapy. Epidemiological and laboratory data were collected. Renal sonography was also performed on each patient to evaluate the formation of renal and liver cysts, and the number and size of the cysts were recorded. Approximately 0.84 % of all HD patients were found to be r-HuEPO independent. The non-ESA group had a higher proportion of men (79.6 vs. 58.3 %), a longer duration of renal replacement therapy (RRT) (8.6 ± 6.1 vs. 5.1 ± 3.3 years), a higher prevalence of adult polycystic kidney disease (APKD) (46.3 vs. 9.7 %), a higher prevalence of hepatitis C virus (HCV) liver disease (26.2 vs. 3.2 %, P < 0.01), and had older patients (63.3 ± 13.6 vs. 49.6 ± 13.5 years). Endogenous erythropoietin levels in the non-ESA group were significantly higher than those in the ESA group (61.8 ± 27.1 vs. 29.3 ± 11.7 mU/ml). Non-ESA patients had a significantly higher number of renal (38.1 vs. 13.2 %) and hepatic cysts (9.3 vs. 1.9 %), which were also larger in size (2.9 ± 1.6 vs. 1.3 ± 0.3 cm) compared with those of patients in the ESA group. No significant difference in iron metabolism was found between two groups. In the multivariate Cox analysis, the independent predictor factors for the absence of anemia in these HD patients were the number of renal cysts >6 cysts (95 % CI 1.058-1.405; P = 0.00), endogenous erythropoietin levels (95 % CI 1.139-1.361; P = 0.05), HCV+ liver disease (95 % CI 1.129-1.316; P = 0.01), and time on RRT (95 % CI 1.019-1.263; P = 0.05). To our knowledge, this study is the first to report on r-HuEPO independence among Chinese HD patients. The prevalence among Chinese chronic HD patients is significantly lower than that reported in the literature. Factors contributing to this condition are complex and multiple. The frequency of this condition is higher in men and in older patients with long-term RRT, in patients with HCV+ liver disease, and in APKD patients. This condition is associated with increased endogenous erythropoietin production and the presence of renal and hepatic cysts.

Haemoglobin Mass and Running Time Trial Performance after Recombinant Human Erythropoietin Administration in Trained Men

Recombinant human erythropoietin (rHuEpo) increases haemoglobin mass (Hbmass) and maximal oxygen uptake ( O2 max).PurposeThis study defined the time course of changes in Hbmass, O2 max as well as running time trial performance following 4 weeks of rHuEpo administration to determine whether the laboratory observations would translate into actual improvements in running performance in the field.Methods19 trained men received rHuEpo injections of 50 IU•kg−1 body mass every two days for 4 weeks. Hbmass was determined weekly using the optimized carbon monoxide rebreathing method until 4 weeks after administration. O2 max and 3,000 m time trial performance were measured pre, post administration and at the end of the study.ResultsRelative to baseline, running performance significantly improved by ∼6% after administration (10∶30±1∶07 min:sec vs. 11∶08±1∶15 min:sec, p<0.001) and remained significantly enhanced by ∼3% 4 weeks after administration (10∶46±1∶13 min:sec, p<0.001), while O2 max was also significantly increased post administration (60.7±5.8 mL•min−1•kg−1 vs. 56.0±6.2 mL•min−1•kg−1, p<0.001) and remained significantly increased 4 weeks after rHuEpo (58.0±5.6 mL•min−1•kg−1, p = 0.021). Hbmass was significantly increased at the end of administration compared to baseline (15.2±1.5 g•kg−1 vs. 12.7±1.2 g•kg−1, p<0.001). The rate of decrease in Hbmass toward baseline values post rHuEpo was similar to that of the increase during administration (−0.53 g•kg−1•wk−1, 95% confidence interval (CI) (−0.68, −0.38) vs. 0.54 g•kg−1•wk−1, CI (0.46, 0.63)) but Hbmass was still significantly elevated 4 weeks after administration compared to baseline (13.7±1.1 g•kg−1, p<0.001).ConclusionRunning performance was improved following 4 weeks of rHuEpo and remained elevated 4 weeks after administration compared to baseline. These field performance effects coincided with rHuEpo-induced elevated O2 max and Hbmass.

Erythropoietin Induced Erythroid Precursor Pool Depletion Causes Erythropoietin Hyporesponsiveness

Abstract 5156 Background:Erythropoietin (EPO) hyporesponsiveness is demonstrated by a persistence of anemia despite high dose of recombinant human erythropoietin (rHuEPO) or requirement of large doses to maintain the target hemoglobin concentration. The purpose of this study is to demonstrate that the bone marrow depletion induced by rHuEPO treatment may another contributing factor to hyporesponsiveness. Methods:Healthy Wistar rats were given single dose (SD) or multiple doses (MD) of rHuEPO. In MD study, animals were challenged with thrice-weekly (100 IU/kg) over two weeks and the pharamcodynamic biomarkers included reticulocyte (RET) and red blood cells (RBC) counts, and hemoglobin (HGB) concentrations. In SD study, in addition to the biomarkers in the peripheral blood, the erythropoietic responses in bone marrow and spleen were also quantified using a flow cytometric immunophenotyping technique. The total marrow and spleen cellularity was quantitatively assessed using flow cytometry. A mathematical approach involving measuring RET age distribution was developed to evaluate the RET loss due to neocytolysis. The pharmacokinetics of rHuEPO was assessed by measuring serum concentrations over time using ELISA. Result:In MD study, a slow and oscillatory decline of RET response was observed before the administration of the last dose on day 11. The RET kept decreasing below the baseline and reached a nadir on day 22, followed by a slow return to the baseline on day 28. These observations demonstrated the tolerance and rebound phenomena. In SD study, the RET decreased below the baseline after day 6. A depletion of the bone marrow erythroid precursor cells was also observed. Meanwhile, neocytolysis of RET was only observed from day 3–5 after rHuEPO injection. These results suggested that the reduced levels of RET after day 6 resulted from the depletion in the erythroid precursor cells in bone marrow induced by rHuEPO treatment. Conclusion:The EPO hyporesponsiveness is of clinical importance because it is associated with an increased risk of death or cardiovascular events. The findings in this study demonstrate that EPO-induced erythroid precursor depletion may contribute to the rHuEPO hyporesponsiveness. When the erythroid precursor cells are depleted, an increase of rHuEPO dose would not show much benefit, due to the smaller number of cells present to initiate the erythropoiesis. These findings provide additional justification for reducing the doses of erythropoietin stimulating agents in anemic patients demonstrating hyporesponsiveness. Disclosures:No relevant conflicts of interest to declare.

Epoetin administrated after cardiac surgery: effects on renal function and inflammation in a randomized controlled study

BackgroundExperimentally, erythropoietin (EPO) has nephroprotective as well as immunomodulatory properties when administered after ischemic renal injury. We tested the hypothesis that different doses of recombinant human EPO administered to patients after cardiac surgery would minimize kidney lesions and the systemic inflammatory response, thereby decreasing acute kidney injury (AKI) incidence.MethodsIn this double-blinded randomized control study, 80 patients admitted to the ICU post-cardiac surgery were randomized by computer to receive intravenously isotonic saline (n = 40) versus α-Epoetin (n = 40): either 40000 IU (n = 20) or 20000 IU (n = 20). The study lasted one year. The primary outcome was the change in urinary NGAL concentration from baseline and 48 h after EPO injection. Creatinine, cystatine C and urinary NGAL levels were measured on the day of randomization and 2–4 days after EPO injection. To assess acute inflammatory response, serum cytokines (IL6 and IL8) were measured at randomization and four days after r-HuEPO injection. Patients and care-takers were blinded for the assignment.ResultsNo patient was excluded after randomization. Patient groups did not differ in terms of age, gender, comorbidities and renal function at randomization. The rate of AKI assessed by AKIN criteria was 22.5% in our population. EPO treatment did not significantly modify the difference in uNGAl between 48 hours and randomization compared to placebo [2.5 ng/ml (−17.3; 22.5) vs 0.7 ng/ml (−31.77; 25.15), p = 0.77] and the incidence of AKI was similar. Inflammatory cytokines levels were not influenced by EPO treatment. Mortality and hospital stays were similar between the groups and no adverse event was recorded.ConclusionIn this randomized-controlled trial, α-Epoetin administrated after cardiac surgery, although safe, demonstrated neither nephroprotective nor anti-inflammatory properties.Trial registration numberNCT00676234

Erythropoietin protects against cisplatin-induced nephrotoxicity by attenuating endoplasmic reticulum stress-induced apoptosis

The anticancer drug cisplatin (CP)-induced nephrotoxicity associated with apoptosis plays crucial roles in tumor patients. Erythropoietin (EPO) has recently been shown to enhance recovery from CP-induced acute kidney injury (AKI) in rats by exerting anti-apoptotic effects. However, the molecular mechanisms of Erythropoietin protects against CP-induced AKI are not very clear. The present study investigated the protective effects of erythropoietin (EPO) against CP-induced nephrotoxicity and the possible mechanism in rats. Sprague-Dawley (SD) rats were randomly divided into four groups: (1) Control group (n=16): which received a single intraperitoneal injection of vehicle (0.9% saline; 5 mL/kg); (2) CP group (n=16): which received a single intraperitoneal injection of 10.0 mg/kg CP (previously dissolved at 2.0 mg/mL in 0.9% saline solution); (3) CP+rHuEPO group (n=16): which received rHuEPO (5000 U/kg) with co-injection of the LY294002 vehicle dimethyl sulfoxide (DMSO, 33.3 µL/kg; Sigma, St. Louis, MO, USA) by tail vein injection 2 days before CP administration, 15 min before CP administration, and 2 days after CP administration; (4) CP+rHuEPO+LY group (n=16): which received LY294002 (0.3 mg/kg) 10 min before rHuEPO administration by three injections into the tail vein at 2-day intervals beginning 2 days before CP administration. Apoptosis was assessed by the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) method. The expressions of C/EBP-homologous protein (CHOP), glucose-regulated protein 78 (GRP78), caspase-12, the phosphorylation of Akt, cleaved-caspase-3 and EPO receptor (EPOR) were measured after CP-treated. In addition, light microscopy and immunohistochemistry examinations were performed. The levels of serum urea and creatinine were increased at 96 h after CP-administered group. The eHuEPO-administered group had significantly lower serum creatinine levels. CP caused an increase in TUNEL-positive cells that was accompanied and apoptotic cell death induced by CP was significantly abrogated by rHuEPO at 96h by morphological evidence of apoptosis. The over-expression of CP-induced endoplasmic reticulum (ER) stress markers (CHOP and GRP78) and activation of caspase-12 were suppressed by rHuEPO, which also attenuated the CP-induced suppression of phosphatidylinositol-3kinase/Akt (PI3K/Akt) signaling in rat kidneys. In addition, LY294002 diminished the effect of rHuEPO on renal protection and antiapoptosis. Injection of rHuEPO enhance recovery from CP-induced AKI in rats by ameliorating renal functional impairment and exerting important anti-apoptotic effects. However, rHuEPO inhibited CP-induced AKI by a possible mechanism involving PI3K/Akt activation and the inhibition of ER stress-mediated apoptosis.

Erythropoietin administration acutely stimulates resting energy expenditure in healthy young men

Treatment with recombinant human erythropoietin (rHuEpo) improves insulin sensitivity in patients with end-stage renal disease, and animal studies indicate that Epo increases fat oxidation. However, the metabolic effects of rHuEpo have never been experimentally studied in healthy humans. The aim was to investigate the effects of an acute rHuEpo bolus on substrate metabolism and insulin sensitivity in healthy young men. Ten healthy young men were studied in a single-blinded, randomized crossover design with a 2-wk washout period receiving 400 IU/kg rHuEpo or placebo. Substrate metabolism was evaluated by indirect calorimetry and tracer infusions, and insulin sensitivity by a hyperinsulinemic euglycemic clamp; and PCR and Western blotting measured protein expression and content, respectively. Resting energy expenditure (REE) increased significantly after rHuEpo [basal: 1,863.3 ± 67.2 (kcal/day) (placebo) vs. 2,041.6 ± 81.2 (rHuEpo), P < 0.001; clamp: 1,903.9 ± 68.3 (placebo) vs. 2,015.7 ± 114.4 (rHuEpo), P = 0.03], but the increase could not be explained by changes in mRNA levels of uncoupling protein 2 or 3. Fat oxidation in the basal state tended to be higher after rHuEpo but could not be explained by changes in mRNA levels of CPT1 and PPARα or AMPK and ACC protein phosphorylation. Insulin-stimulated glucose disposal, glucose metabolism, and whole body and forearm protein metabolism did not change significantly in response to rHuEpo. In conclusion, a single injection of rHuEpo acutely increases REE in healthy human subjects. This calorigenic effect is not accompanied by distinct alterations in the pattern of substrate metabolism or insulin sensitivity.

Erythropoietin Treatment Is Associated with Decreased Blood Glucose Levels: A Preliminary Study in Hematologic Patients

Abstract 4793 Introduction:Erythropoietin (EPO) is the major hormone which enhances proliferation and maturation of the red cell lineage, and its recombinant form (rHuEPO) is used extensively to treat various types of anemia. rHuEPO has also been found to exert effects in other organ systems, and our previous work has demonstrated an immunomodulatory role for EPO. Recently, we have also found that mice exposed to high levels of EPO (either rHuEPO injections or transgenic mice overexpressing human EPO), have significantly lower levels of blood glucose than those of their respective controls (Katz et al., J Endocrinol 2010;205:87-95). The current retrospective study was designed to determine whether rHuEPO treatment in hematologic patients, is associated with decreased blood glucose levels. Methods:Patients receiving rHuEPO were examined, comparing glucose levels (morning blood tests, assumed to be fasting) while on rHuEPO treatment to those off treatment. All patients served as their own controls. To test the association between rHuEPO treatment and blood glucose levels, we employed a mixed-model repeated-measures analysis of variance (ANOVA). Results:The charts of 19 patients were reviewed to determine the starting date of rHuEPO and the levels of blood glucose in relation to rHuEPO treatment. Mean age: 77 (range: 54–93). Thirteen patients had myelodysplastic syndrome, and six had multiple myeloma. Two patients had diabetes mellitus. Average glucose levels (mean±95%CI) without rHuEPO treatment were 116.07±4.98. Glucose measurements were available for a median of 9.23 (interquartile range: 7.90–16.80) months after the initiation of rHuEPO treatment. The average glucose level over that period of time was 101.77±4.86 (p<0.0001). The two diabetic patients also demonstrated a trend towards reduced serum blood glucose and lower HbA1C while being treated with rHuEPO. Conclusions:Treatment of hematologic patients with rHuEPO is associated with significantly lower blood glucose levels, and might serve in the future to improve glucose control in anemic patients with hyperglycemia. Further studies with both diabetic and non-diabetic patients are currently underway to clarify this association. Disclosures:No relevant conflicts of interest to declare.