Administration Of Recombinant Human Erythropoietin Research Articles

Discovery of Biomarkers of a Recombinant Human Erythropoietin Administration to Thoroughbred Geldings by Label‐Free Proteomics

ABSTRACTErythropoiesis‐stimulating agents (ESAs) continue to be a significant threat to the integrity of human and equine sports. Besides conventional direct testing, monitoring the biomarkers associated with the effects of ESAs may provide a complementary approach via indirect detection to enhance doping control. In this study, we applied label‐free proteomics to discover plasma protein biomarkers in Thoroughbred geldings after administration with a long‐acting form of recombinant human erythropoietin (rhEPO), methoxy polyethylene glycol epoetin beta, Mircera. Increased haematocrit, haemoglobin and red blood cell (RBC) levels were evidenced as early as 4 days post‐administration in all three horses to varying extents. Tryptic peptides were obtained from plasma samples and analysed by nanoflow ultra‐high‐performance liquid chromatography–high‐resolution tandem mass spectrometry (nano‐UHPLC‐HRMSMS) using data‐independent acquisition. Differential protein abundance analysis has shortlisted seven protein biomarker candidates that showed significant changes specifically after Mircera administration in the treated but not in the control geldings, which comprised downregulation of two proteins, haptoglobin (HP) and haemopexin (HPX), and upregulation of five proteins, transferrin receptor 1 (TFR1), phospholipid transfer protein (PLTP), tenascin C (TNC), vascular cell adhesion molecule 1 (VCAM1) and galectin 3 binding protein (LGALS3BP). Multivariate analysis of plasma proteome has allowed the classification of control and treated samples. This is the first report on the discovery of plasma protein biomarkers of rhEPO administration to geldings. The results lay a foundation for applications of protein biomarkers for controlling the misuse of ESAs.

Effects of Recombinant Human Erythropoietin Administration in Premature Infants with Severe Intraventricular Hemorrhage: A Single-Center Experience

Purpose: We investigated the effects of early postnatal administration of erythropoietin (EPO) on neurodevelopmental outcomes and morbidities in preterm infants with severe grades of intraventricular hemorrhage (IVH).Methods: We retrospectively reviewed the medical records of preterm infants of gestational age 23<sup>+0</sup> weeks to 31<sup>+6</sup> weeks, who were diagnosed with severe grades of IVH and received EPO over at least 2 weeks. We compared clinical characteristics, major complications, and neurodevelopmental impairment between the two groups. The primary outcome was severe neurodevelopmental impairment at 18 to 26 months of corrected age. Severe neurodevelopmental impairment was defined as a mental developmental index or psychomotor developmental index of <70 on the Bayley Scales of Infant Development II or diagnosis of cerebral palsy.Results: The study included 33 preterm infants (mean gestational age 25.2±1.6 weeks and mean birth weight 775.1±224.5 g). EPO was administered at a dose of 400 or 1,000 IU/kg thrice weekly and was maintained over a mean period of 58.6± 25.9 days beginning from 10.7±6.9 days after birth. We observed no difference in perinatal characteristics between the EPO (n=14) and the control group (n=19). Similarly, severe neurodevelopmental impairment rates did not differ between the EPO (85.7%) and control groups (78.9%). The incidence of neonatal morbidities including bronchopulmonary dysplasia, necrotizing enterocolitis, and retinopathy of prematurity was also similar between the EPO and control groups.Conclusion: Early administration of EPO did not reduce the risk of severe neurodevelopmental impairment in preterm infants with severe IVH.

Pharmacological Management of Germinal Matrix-Intraventricular Hemorrhage.

Germinal matrix-intraventricular hemorrhage (GM-IVH) is among the devastating neurological complications with mortality and neurodevelopmental disability rates ranging from 14.7% to 44.7% in preterm infants. The medical techniques have improved throughout the years, as the morbidity-free survival rate of very-low-birth-weight infants has increased; however, the neonatal and long-term morbidity rates have not significantly improved. To this date, there is no strong evidence on pharmacological management on GM-IVH, due to the limitation of well-designed randomized controlled studies. However, recombinant human erythropoietin administration in preterm infants seems to be the only effective pharmacological management in limited situations. Hence, further high-quality collaborative research studies are warranted in the future to ensure better outcomes among preterm infants with GM-IVH.

Effect of Early High-Dose Recombinant Human Erythropoietin on Behavior and Quality of Life in Children Aged 5 Years Born Very Preterm

In light of the promising neuroprotective properties of recombinant human erythropoietin (RHEpo), the Swiss EPO Neuroprotection Trial was started to investigate its effect on neurodevelopment in very preterm infants. The results of the primary and secondary outcome analysis did not show any effect of RHEpo on cognitive performance, neuromotor outcomes, or somatic growth of the study participants at ages 2 or 5 years. To investigate whether early high-dose RHEpo improves behavioral outcomes and health-related quality of life (HRQoL) at age 5 years. This was a prespecified secondary analysis of the double-blind, placebo-controlled, multicenter Swiss EPO Neuroprotection randomized clinical trial, which was conducted at 5 level-III perinatal centers in Switzerland. Infants born between 26 weeks 0 days' and 31 weeks 6 days' gestation were recruited between 2005 and 2012 and followed-up until age 5 years (last follow-up in 2018). Data were analyzed from January 6 to December 31, 2021. Infants were assigned to receive either RHEpo (3000 IU/kg) or placebo (saline, 0.9%) intravenously 3 times within the first 42 hours after birth. The prespecified parent-reported measures of behavioral outcomes and health-related quality of life (HRQoL) of their children at the age of 5 years were assessed by two standardized questionnaires: the Strengths and Difficulties Questionnaire (behavioral outcomes) and the KIDSCREEN-27 (HRQoL). Among 448 randomized infants, 228 infants were assigned to the RHEpo group and 220 infants were assigned to the placebo group. Questionnaire data were available for 317 children (71%) at a mean (SD) age of 5.8 (0.4) years (mean [SD] gestational age at birth, 29.3 [1.6] weeks; mean [SD] birth weight 1220 [340] grams; 128 [40%] female infants). At the age 5 years follow-up, the mean (SD) total difficulties score in the RHEpo group (8.41 [5.60] points) was similar to that of the placebo group (7.76 [4.81]) (P = .37). There were no statistically significant differences between the groups in any other outcome measures. This secondary analysis of a randomized clinical trial showed no evidence for an effect of early high-dose RHEpo administration on behavioral outcomes or HRQoL in children born very preterm at early school age. ClinicalTrials.gov Identifier: NCT00413946.

Recombinant human erythropoietin induces neuroprotection, activates MAPK/CREB pathway, and rescues fear memory after traumatic brain injury with delayed hypoxemia in mice

Therapeutic interventions targeting secondary insults, such as delayed hypoxemia, provide a unique opportunity for treatment in severe traumatic brain injury (TBI). Erythropoietin (EPO) is a hypoxia-responsive cytokine with important roles in neurodevelopment, neuroprotection and neuromodulation. We hypothesized that recombinant human erythropoietin (rhEPO) administration would mitigate injury in a combined injury model of TBI and delayed hypoxemia. Utilizing a clinically relevant murine model of TBI and delayed hypoxemia, we characterized how ongoing rhEPO administration influenced neurogenesis, neuroprotection, synaptic density and, behavioral outcomes early after TBI, and the impact on long-lasting outcomes 6 months after injury. We employed novel object recognition (NOR) and fear conditioning to assess long-term memory. At 1-month post-injury, we observed a significant increase in cued-fear memory response in the rhEPO-injured mice compared with vehicle-injured mice. This was associated with neuroprotection and neurogenesis in the hippocampus and mitogen-activated protein kinase (MAPK)/cAMP response element-binding protein (CREB) signaling activation and increased of excitatory synaptic density in the amygdala. Early rhEPO treatment after injury reduced neurodegeneration and increased excitatory synaptic density in the hippocampus and amygdala at 6 months post-injury. However at 6 months post-injury (4 months after discontinuation of rhEPO), we did not observe changes in behavioral assessments nor MAPK/CREB pathway activation. In summary, these data demonstrate that ongoing rhEPO treatment initiated at a clinically feasible time point improves neurological, cognitive, and histological outcomes after TBI in the setting of secondary hypoxemic insults.

Integrating Whole Blood Transcriptomic Collection Procedures Into the Current Anti-Doping Testing System, Including Long-Term Storage and Re-Testing of Anti-Doping Samples.

Introduction: Recombinant human erythropoietin (rHuEPO) administration studies involving transcriptomic approaches have demonstrated a gene expression signature that could aid blood doping detection. However, current anti-doping testing does not involve collecting whole blood into tubes with RNA preservative. This study investigated if whole blood in long-term storage and whole blood left over from standard hematological testing in short-term storage could be used for transcriptomic analysis despite lacking RNA preservation. Methods: Whole blood samples were collected from twelve and fourteen healthy nonathletic males, for long-term and short-term storage experiments. Long-term storage involved whole blood collected into Tempus™ tubes and K2EDTA tubes and subjected to long-term (i.e., ‒80°C) storage and RNA extracted. Short-term storage involved whole blood collected into K2EDTA tubes and stored at 4°C for 6‒48 h and then incubated at room temperature for 1 and 2 h prior to addition of RNA preservative. RNA quantity, purity, and integrity were analyzed in addition to RNA-Seq using the MGI DNBSEQ-G400 on RNA from both the short- and long-term storage studies. Genes presenting a fold change (FC) of >1.1 or < ‒1.1 with p ≤ 0.05 for each comparison were considered differentially expressed. Microarray analysis using the Affymetrix GeneChip® Human Transcriptome 2.0 Array was additionally conducted on RNA from the short-term study with a false discovery ratio (FDR) of ≤0.05 and an FC of >1.1 or < ‒1.1 applied to identify differentially expressed genes. Results: RNA quantity, purity, and integrity from whole blood subjected to short- and long-term storage were sufficient for gene expression analysis. Long-term storage: when comparing blood tubes with and without RNA preservation 4,058 transcripts (6% of coding and non-coding transcripts) were differentially expressed using microarray and 658 genes (3.4% of mapped genes) were differentially expressed using RNA-Seq. Short-term storage: mean RNA integrity and yield were not significantly different at any of the time points. RNA-Seq analysis revealed a very small number of differentially expressed genes (70 or 1.37% of mapped genes) when comparing samples stored between 6 and 48 h without RNA preservative. None of the genes previously identified in rHuEPO administration studies were differently expressed in either long- or short-term storage experiments. Conclusion: RNA quantity, purity, and integrity were not significantly compromised from short- or long-term storage in blood storage tubes lacking RNA stabilization, indicating that transcriptomic analysis could be conducted using anti-doping samples collected or biobanked without RNA preservation.

Data from a microdosed recombinant human erythropoietin administration study applying the new biotinylated clone AE7A5 antibody and a further optimized sarcosyl polyacrylamide gel electrophoresis protocol.

Erythropoietin (EPO) is a hormone, which stimulates the production of red blood cells. Due to its performance-enhancing effect, it is prohibited by the World Anti-Doping Agency (WADA). In order to reduce the detection window of EPO doping, athletes have been applying low doses of recombinant EPO (e.g., <10IU/kg body weight, daily or every second day) instead of larger doses twice or more per week (e.g., 30IU/kg). Microdoses of Retacrit (epoetin zeta), an EPO biosimilar, were administered intravenously and subcutaneously to human males and females. Urine and serum samples were collected and analysed applying the new biotinylated clone AE7A5 EPO antibody and a further optimized sarcosyl polyacrylamide gel electrophoresis (SAR-PAGE) protocol. With the improved protocol, microdosed Retacrit (7.5 IU/kg body weight [BW]) was detectable for at least 52h after intravenous administration. Detection windows were approximately the same for serum and urine and doubled after subcutaneous administration (~104h). Previous studies applying different electrophoretic techniques and the not further optimized SAR-PAGE protocol revealed considerably shorter detection windows for recombinant human erythropoietin (rhEPO) microdoses. Because the new biotinylated antibody performed significantly more sensitive than the nonbiotinylated version, the new protocol will improve the sensitivity and hence detectability of recombinant EPO in doping control.

Current Evidence on the Protective Effects of Recombinant Human Erythropoietin and Its Molecular Variants against Pathological Hallmarks of Alzheimer's Disease.

Substantial evidence in the literature demonstrates the pleiotropic effects of the administration of recombinant human erythropoietin (rhEPO) and its molecular variants in different tissues and organs, including the brain. Some of these reports suggest that the chemical properties of this molecule by itself or in combination with other agents (e.g., growth factors) could provide the necessary pharmacological characteristics to be considered a potential protective agent in neurological disorders such as Alzheimer’s disease (AD). AD is a degenerative disorder of the brain, characterized by an aberrant accumulation of amyloid β (Aβ) and hyperphosphorylated tau (tau-p) proteins in the extracellular and intracellular space, respectively, leading to inflammation, oxidative stress, excitotoxicity, and other neuronal alterations that compromise cell viability, causing neurodegeneration in the hippocampus and the cerebral cortex. Unfortunately, to date, it lacks an effective therapeutic strategy for its treatment. Therefore, in this review, we analyze the evidence regarding the effects of exogenous EPOs (rhEPO and its molecular variants) in several in vivo and in vitro Aβ and tau-p models of AD-type neurodegeneration, to be considered as an alternative protective treatment to this condition. Particularly, we focus on analyzing the differential effect of molecular variants of rhEPO when changes in doses, route of administration, duration of treatment or application times, are evaluated for the improved cellular alterations generated in this disease. This narrative review shows the evidence of the effectiveness of the exogenous EPOs as potential therapeutic molecules, focused on the mechanisms that establish cellular damage and clinical manifestation in the AD.

Hyperhydration using different hydration agents does not affect the haematological markers of the athlete biological passport in euhydrated volunteers

ABSTRACT Athlete Biological Passport (ABP) is an indirect approach, implemented by WADA, aimed at detecting blood manipulation based on abnormal changes in haematological markers. Cases report the use of hyperhydration as masking method during anti-doping urine sample collection which could potentially mask suspicious fluctuations on ABP profiles. This study investigated the hyperhydration effect on haemoglobin concentration, reticulocyte percentage and OFF-hr score (an algorithm based on haemoglobin concentration and reticulocyte percentage), with and without recombinant human erythropoietin (rHuEPO) administration. A five-week clinical study performed; Baseline and rHuEPO Phase. Water and a sports drink were used as hyperhydration agents. To examine the hyperhydration effect on the normal ABP profile per volunteer, hyperhydration was implemented at 0, 24 and 48 hours during the baseline. During the rHuEPO phase, volunteers received Epoetin beta (3000 IU) with hyperhydration to be implemented at 0, 24 and 48 hours after drug administration. Blood and urine samples were collected and analysed according to WADA guidelines. No significant effect on ABP markers was observed due to hyperhydration at any time during the study. Pre- and post-hyperhydration data were not statistically different compared to individual baseline data. In conclusion, hyperhydration does not affect the ABP haematological markers under the examined conditions.

The effects of macrophage-specific Vhl knockout on steady state and stress erythropoiesis in mice

Abstract Objective Macrophages are known to assist erythropoiesis. However, the effect of macrophage specific Vhl knockout on erythropoiesis is unclear. Methods We generated Tg(Csf1r-Cre/Esr1);VhlF/F mice to achieve inducible macrophage-specific Vhl knockout. Tg(Csf1r-Cre/Esr1);ROSA26CAG-tdTomato/+ was also generated to examine the knockout efficiency. Erythropoiesis was determined by analyses of complete blood count (CBC), spleen weight, and cell surface expression of TER-119 and CD71 in the bone marrow and spleen. Based on FSC-A and surface CD71 expression, we defined three different red blood cell (RBC) maturation stages as erythroblast, reticulocyte, and mature RBC. Stress erythropoiesis was induced by administration of recombinant human erythropoietin (rhEPO) 4U/gBW subcutaneously thrice per week for 6 doses. Results Tamoxifen administration in Tg(Csf1r-Cre/Esr1);ROSA26CAG-tdTomato/+ mice resulted in expression of tdTomato in CD11b(+)F4/80(+) cells in the spleen (79%) and peripheral blood mononuclear cell (PBMC) (48%). In steady state erythropoiesis, tamoxifen administration in Tg(Csf1r-Cre/Esr1);VhlF/F mice did not result in changes of CBC, spleen weight, ratio of TER-119(+) cells in live cells, or RBC maturation stages in the spleen and bone marrow. In stress erythropoiesis, administration of rhEPO resulted in polycythemia. However, no significant changes in Hct, ratio of TER-119(+) cells in live cells, or RBC maturation stages could be observed between Tg(Csf1r-Cre/Esr1);VhlF/F and littermate control mice after tamoxifen administration. Conclusion Macrophage specific knockout of Vhl in mice did not have significant effects on steady state erythropoiesis and rhEPO induced stress erythropoiesis.

Effect of enteral erythropoietin on feeding-related complications in preterm newborns: A pilot randomized controlled study

Background and study aimsTo evaluate the effects of enteral administration of recombinant human erythropoietin (rhEPO) on feeding-related complications in preterm infants. Patients and methodsThis double-blind, randomized controlled pilot study enrolled 120 preterm infants born ≤ 32 weeks’ gestation who were admitted to the neonatal intensive care unit in a tertiary hospital; 60 patients randomly received recombinant human erythropoietin while the other 60 received placebo. Newborns who underwent cardiopulmonary resuscitation, infants with genetic syndromes, infants with inborn errors of metabolism, infants with major congenital or acquired gastrointestinal tract malformations, infants with previous use of parenteral growth factors such as recombinant human erythropoietin and granulocyte-macrophage colony-stimuating factor (GM-CSF) and infants previously treated with intravenous immunoglobulin were excluded. Overall, 48 patients withdrew from the study because of intravenous haematopoietic growth factor intake or death before treatment was completed. A total of 72 preterm infants remained in the study: 36 preterm infants in the erythropoietin (EPO) group, and 36 preterm infants in the placebo group. The day that enteral feeding was successfully started, the time to establishing one-half, two-thirds, and full enteral feedings (reaching at least 150 mL/kg/day), the number of episodes of feeding intolerance, the time to regain birth weight and the incidence of necrotizing enterocolitis (NEC) were recorded. ResultsBoth groups showed no significant difference in the time to achieve one-half, two-thirds, or full enteral feeding, no signs of feeding intolerance, and no cases of NEC were recorded. ConclusionEnteral erythropoietin does not appear to affect feeding intolerance or NEC incidence.

Effect of preoperative recombinant human erythropoietin administration on inflammatory lung injury due to cardiopulmonary bypass

Objective To discuss the effects of preoperative use of recombinant human erythropoietin (rHuEPO) on inflammatory lung injury patients after cardiopulmonary bypass (CPB) under extracorporeal circulation. Methods A total of 54 patients who were scheduled to receive elective open cardiac operations under CPB were enrolled. They were divided into two groups(n=27). rHuEPO group: patients were titrated intravenously with rHuEPO (100 IU/kg, diluted into 50 ml normal saline) for consecutive three days at the same time period before operation. Control group: equivalent normal saline in place of rHuEPO was given to patients via venous injection. Peak airway pressure (Ppeak), plateau pressure (Pplat), and pulmonary dynamic compliance (Cdyn) were well monitored and recorded before CPB (T1), immediately after chest closure (T2), and 2, 4 h and 6 h after surgery (T3, T4, and T5). At T1, T2, T5, and 12, 24, 48 h, and 72 h after surgery (T6, T7, T8, and T9), arterial oxygenation indices (OI) were also recorded. Furthermore, at pre-rHuEPO treatment (T0), T1, T2, T5, T6, T7, T8, and T9, the plasma levels of the tumor necrosis factor (TNF)-α and interleukin (IL)-1β and IL-10 were measured. The time of mechanical ventilation and stay in intense care unit (ICU), discharge time and hospitalization stay were also recorded. Results Compared with the control group, Cdyn in the rHuEPO group at T2-T5 were significantly increased (P<0.05), whereas Ppeak and Pplat were decreased (P<0.05). OI values of rHuEPO group at T2 and T5-T9 were significantly higher than that of control group(P<0.05). It was demonstrated that at any time point after closing chest, the plasma concentrations of TNF-α, IL-1β, and IL-10 in both groups were relatively elevated compared with those before, while the concentrations of TNF-α and IL-1β in the rHuEPO group were lower than those in control group (P<0.05). Compared with the control group, patients receiving rHuEPO treatment underwent an apparent reduction in both mechanical ventilation and staying time in ICU (P<0.05). Conclusions Preoperative rHuEPO administration can attenuate the inflammatory lung injury after CPB via the anti-inflammation pathway and ameliorate pulmonary functions. Key words: Recombinant human erythropoietin; Cardiopulmonary bypass; Lung injury; Inflammatory response

The effect of the administration of recombinant human erythropoietin on anemia in patients on dialysis

As a VEGF-targeting agent, sorafenib has been used to treat a number of solid tumors but can easily lead to adverse vascular effects. To elucidate the underlying mechanism, rat mesenteric arteries were subjected to organ cultured in the presence of different concentrations of sorafenib (0, 3, 6 and 9 mg/L) with or without inhibitors (U0126, 10−5 M; SB203580, 10−5 M; SP200126, 10−5 M) of MAPK kinases, and then acetylcholine- or sodium nitroprusside-induced vasodilation and sarafotoxin 6c-induced vasoconstriction were monitored by a sensitive myograph. The NO synthetases, the nitrite levels, the endothelial marker CD31,the ETB and ETA receptors and the phosphorylation of MAPK kinases were studied. Next, rats were orally administrated by sorafenib for 4 weeks (7.5 and 15 mg/kg/day), and their blood pressure, plasma ET-1, the ETB and ETA receptors and the phosphorylation of MAPK kinases in the mesenteric arteries were investigated. The results showed that sorafenib impairs endothelium-dependent vasodilation due to decreased NO levels and the low expression of eNOS and iNOS. Weak staining for CD31 indicated that sorafenib induced endothelial damage. Moreover, sorafenib caused the upregulation of vasoconstrictive ETB receptors, the enhancement of ETB receptor-mediated vasoconstriction and the activation of JNK/MAPK. Blocking the JNK, ERK1/2 and p38/MAPK signaling pathways by using the inhibitors significantly abolished ETB receptor-mediated vasoconstriction. Furthermore, it was observed that the oral administration of sorafenib caused an increase in blood pressure and plasma ET-1, upregulation of the ETB receptor and the activation of JNK in the mesenteric arteries. In conclusion, sorafenib not only impairs endothelium-dependent vasodilatation but also enhances ETB receptor-mediated vasoconstriction, which may be the causal factors for hypertension and other adverse vascular effects in patients treated with sorafenib.

Effect of renal function and dialysis modality on daprodustat and predominant metabolite exposure.

BackgroundCurrent therapies for anemia of chronic kidney disease (CKD) include administration of supplemental iron (intravenous and/or oral), blood transfusions and replacement of erythropoietin through the administration of recombinant human erythropoietin (rhEPO) and rhEPO analogs, each with limitations. Daprodustat is an orally active, small molecule hypoxia-inducible factor-prolyl hydroxylase inhibitor that is currently in Phase 3 clinical studies. As it is well appreciated that the kidney represents a major route of elimination of many drugs, and daprodustat will be administered to patients with advanced CKD as well as patients with end-stage kidney disease, it is important to characterize the pharmacokinetic profile in these patient populations to safely dose this potential new medicine.Methods The primary objective of these studies, conducted under two separate protocols and with identical assessments and procedures, was to characterize the steady-state pharmacokinetics of daprodustat and the six predominant metabolites (i.e. metabolites present in the highest concentration in circulation) in subjects with normal renal function, anemic non-dialysis (ND)-dependent CKD subjects (CKD Stage 3/4) and anemic subjects on either hemodialysis (HD) or peritoneal dialysis (PD). All enrolled subjects were administered daprodustat 5 mg once daily for 14 days (all except HD subjects) or 15 days (for HD subjects). Blood, urine and peritoneal dialysate were collected at various times for measurement of daprodustat, predominant metabolite, erythropoietin and hepcidin levels.Results The pharmacokinetic properties of steady-state daprodustat peak plasma concentration (Cmax), area under the plasma daprodustat concentration-time curve (AUC) and the time of Cmax (tmax) were comparable between all cohorts in this study. In addition, there was no clinically relevant difference in these properties in the HD subjects between a dialysis and ND day. For CKD Stage 3/4, HD (dialysis day) and PD subjects, the AUC of all daprodustat metabolites assessed was higher, while the Cmax was slightly higher than that in subjects with normal renal function. Over the course of the 14 or 15 days of daprodustat administration, hemoglobin levels were seen to be relatively stable in the subjects with normal renal function, CKD Stage 3/4 and PD subjects, while HD subjects had a decrease of 1.9 gm/dL. All renally impaired subjects appeared to have similar erythropoietin responses to daprodustat, with approximately a 3-fold increase in these levels. In subjects with minimal to no change in hemoglobin levels, hepcidin levels remained relatively stable. Daprodustat, administered 5 mg once daily for 14–15 days, was generally well tolerated with a safety profile consistent with this patient population.Conclusion These studies demonstrated no clinically meaningful change in the pharmacokinetic properties of daprodustat when administered to subjects with various degrees of renal impairment, while for CKD Stage 3/4, HD (dialysis day) and PD subjects, the Cmax and AUC of all daprodustat metabolites assessed were higher than in subjects with normal renal function. Administration of daprodustat in this study appeared to be generally safe and well tolerated.

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%).

Biomolecular changes on mice caput femur after human recombinant erythropoietin administration

Introduction: Osteonecrosis is a process of death of bone tissue which also causes disturbance in the bone’s blood vessel supply. Administration of recombinant human erythropoietin (rHuEPO) may affect cell proliferation by stimulating angiogenesis and it has been proven that cell proliferation during osteogenesis depends heavily on the formation of new blood vessels. Therefore, EPO has a role in bone regeneration. Methods: This research is an experimental study using Randomized post-test control only group design. Rats were divided into 2 groups, P0 which received dexamethasone injection for 5 weeks and group P1 which received dexamethasone injection combined with rHuEpo for 5 weeks. On the last day of the fifth week, the femoral head of the rats were taken for assessment of VEGF (Vascular Endothelial Growth Factor), BMP-2 (Bone Morphogenic Protein-2), osteocytes, osteoblasts and adipocytes levels. The examination results were then analyzed by using SPSS. Results: From the immunohistochemical and histopathologic examination and further SPSS analysis, it is shown that the number of osteocyte in the femoral heads of rats injected with dexamethasone and rHuEpo were significantly higher than those injected with dexamethasone alone (p <0.05). This was also the case with the number of osteoblasts (p <0.05). The expression of BMP-2 and VEGF were also significantly higher in rats injected with dexamethasone and rHuEPO (p <0.05). However, the number of adipocytes in the femoral heads of the rats injected with dexamethasone and rHuEpo were significantly lower than those injected with dexamethasone alone (p <0.05). Conclusion: Administration of rHuEPO in rats induced with dexamethasone was shown to increase the number of osteoblast, osteocyte, BMP-2 expression, and VEGF, but the number of adipocyte was found to be lower than in rats injected with dexamethasone alone.

Effect of Erythropoietin Administration on Myocardial Viability and Coronary Microvascular Dysfunction in Anterior Acute Myocardial Infarction: Randomized Controlled Trial in the Japanese Population.

IntroductionCardioprotective effects of erythropoietin (EPO) on infarcted myocardium in acute myocardial infarction (AMI) patients have been inconclusive. This study aimed to assess the effect of EPO administration on coronary microvascular dysfunction (CMD) and myocardial viability in anterior AMI. We also evaluated the serial changes in CMD and cardiac remodeling in these patients.MethodsPatients with a successful percutaneous coronary intervention (PCI) for the first anterior AMI were randomly assigned to two groups (EPO and control groups), and given single-dose intravenous administration of recombinant human EPO (12,000 IU) or saline after PCI. Delayed-enhanced cardiac magnetic resonance imaging was performed at 1 week after AMI to assess the average of transmural extent of infarction and infarct size. Coronary flow velocity reserve (CFVR) of the left anterior descending coronary artery was measured by Doppler echocardiography at 1 week, 1 month, and 8 months after AMI. All patients underwent clinical follow-up for the assessment of cardiac remodeling.ResultsSixty-one patients (EPO 32, control 29) were eligible for analysis. EPO group (2.4 ± 1.2) had a tendency of smaller transmural extent of infarction than that of control group (2.9 ± 1.1; p = 0.063). CFVR-8 months improved significantly in EPO group (2.9 ± 0.6) compared to control group (2.6 ± 0.5; p = 0.04). Left atrial (LA) volume − 8 months was significantly lower in EPO group (47 ± 11) than those of control group (65 ± 20; p = 0.004).ConclusionsA single medium dose of EPO could have a favorable effect on CMD and LA remodeling in the chronic phase of anterior AMI.Trial RegistrationThe institutional ethics committee of Wakayama Medical University, identifier, 1125.Electronic supplementary materialThe online version of this article (10.1007/s40119-018-0122-1) contains supplementary material, which is available to authorized users.

Erythropoietin stimulates fibroblast growth factor 23 (FGF23) in mice and men.

Fibroblast growth factor 23 (FGF23) is a major endocrine regulator of phosphate and 1,25 (OH)2 vitamin D3 metabolism and is mainly produced by osteocytes. Its production is upregulated by a variety of factors including 1,25 (OH)2 vitamin D3, high dietary phosphate intake, and parathyroid hormone (PTH). Recently, iron deficiency and hypoxia have been suggested as additional regulators of FGF23 and a role of erythropoietin (EPO) was shown. However, the regulation of FGF23 by EPO and the impact on phosphate and 1,25(OH)2 vitamin D3 are not completely understood. Here, we demonstrate that acute administration of recombinant human EPO (rhEPO) to healthy humans increases the C-terminal fragment of FGF23 (C-terminal FGF23) but not intact FGF23 (iFGF23). In mice, rhEPO stimulates acutely (24h) C-terminal FGF23 but iFGF23 only after 4days without effects on PTH and plasma phosphate. 1,25 (OH)2 D3 levels and αklotho expression in the kidney decrease after 4days. rhEPO induced FGF23 mRNA in bone marrow but not in bone, with increased staining of FGF23 in CD71+ erythroid precursors in bone marrow. Chronic elevation of EPO in transgenic mice increases iFGF23. Finally, acute injections of recombinant FGF23 reduced renal EPO mRNA expression. Our data demonstrate stimulation of FGF23 levels in mice which impacts mostly on 1,25 (OH)2 vitamin D3 levels and metabolism. In humans, EPO is mostly associated with the C-terminal fragment of FGF23; in mice, EPO has a time-dependent effect on both FGF23 forms. EPO and FGF23 may form a feedback loop controlling and linking erythropoiesis and mineral metabolism.

EPO Dosage Optimization for Anemia Management: Stochastic Control under Uncertainty Using Conditional Value at Risk

Due to insufficient endogenous production of erythropoietin, chronic kidney disease patients with anemia are often treated by the administration of recombinant human erythropoietin (EPO). The target of the treatment is to keep the patient’s hemoglobin level within a normal range. While conventional methods for guiding EPO dosing used by clinicians normally rely on a set of rules based on past experiences or retrospective studies, model predictive control (MPC) based dosage optimization is receiving attention recently. The objective of this paper is to incorporate the hemoglobin response model uncertainty into the dosage optimization decision making. Two methods utilizing Conditional Value at Risk (CVaR) are proposed for hemoglobin control in chronic kidney disease under model uncertainty. The first method includes a set-point tracking controller with the addition of CVaR constraints. The second method involves the use of CVaR directly in the cost function of the optimal control problem. The methods are compared to set-point tracking MPC and Zone-tracking MPC through computer simulations. Simulation results demonstrate the benefits of utilizing CVaR in stochastic predictive control for EPO dosage optimization.

Erythropoietin Enhances Bone Repair Effects via the Hypoxia-Inducible Factor Signal Pathway in Glucocorticoid-Induced Osteonecrosis of the Femoral Head

BackgroundThis study aimed to determine whether erythropoietin could repair glucocorticoid-induced osteonecrosis of the femoral head after the systemic or local administration of recombinant human erythropoietin. Materials and MethodsGelatin microspheres were used to load recombinant human erythropoietin for local delivery. Forty-eight Wistar rats were included in the glucocorticoid-induced osteonecrosis of the femoral head model and randomly divided into the placebo, systemic erythropoietin and local erythropoietin groups. Eight weeks later, all rats were killed and their tissues were subjected to radiographic, histological, histometric, quantitative polymerase chain reaction and western blot analyses. ResultsOur results show that the use of recombinant human erythropoietin increased bone volume, trabecular number, trabecular thickness and trabecular separation compared with the placebo. Erythropoietin administration significantly improved the expression of runt-related transcription factor 2, alkaline phosphates, hypoxia-inducible factor-1α and vascular endothelial growth factor in the femoral head. We also found that the local injection of erythropoietin could better mediate hypoxia-inducible factor-1α–controlled osteogenic and angiogenic factor expression and better repair the glucocorticoid-induced osteonecrosis of the femoral head. ConclusionsThe use of recombinant human erythropoietin exerted effects on improving the bone structures in glucocorticoid-induced osteonecrosis of the femoral head and up-regulated the expression of runt-related transcription factor 2, alkaline phosphates, hypoxia-inducible factor-1α and vascular endothelial growth factor. It provided a novel idea that erythropoietin administration could repair glucocorticoid-induced osteonecrosis of the femoral head by improving bone formation and angiogenesis and may be associated with the hypoxia-inducible factor-1α pathway. The sequential delivery of erythropoietin from gelatin microspheres seems worth recommending.