To observe the effect of roxadustat on lowering blood lipids in peritoneal dialysis (PD) patients beyond treating anemia.

In a prospective, multicenter clinical study, we randomly assigned (in a 1:1 ratio) 100 PD patients who had received erythropoiesis-stimulating agent therapy for at least 4 weeks to receive either roxadustat or erythropoietin (EPO) for 48 weeks. The blood lipids, hemoglobin, blood pressure, blood glucose, iron metabolism and inflammatory factors were compared between the two groups at 0, 2, 4, 8, 12, 16, 20, 24 and 48 weeks, respectively.

At start of switching to roxadustat, hemoglobin seemed to rise a little faster (102.8 ± 15.4 vs. 97.1 ± 17.3 g/L at 2 weeks, p > 0.05), but there was no significant difference in hemoglobin change between the two groups over the course of observation (p = 0.185). At the early stage of the study (12 weeks), the transferrin saturation (TSAT) of roxadustat group decreased significantly from the baseline (32.7 (20.6) vs. 22.1 (18.7)%, p = 0.001). At the end of the study period (48 weeks), total cholesterol (3.89 ± 0.92 vs. 4.52 ± 1.14 mmol/L, p = 0.012), low density lipoprotein cholesterol (2.24 ± 0.74 vs. 2.63 ± 0.82 mmol/L, p = 0.045) and triglyceride (1.35 (0.86) vs. 1.89 (1.27) mmol/l, p = 0.013) in roxadustat group were significantly lower than those in EPO group.

Roxadustat not only can improve anemia and iron metabolism, but also can reduce serum cholesterol and triglyceride levels in PD patients after switching from the EPO.

Anemia of chronic disease (ACD) is the most frequent clinical issue in patients with chronic disease, ACD is usually secondary to chronic kidney disease (CKD), cancer, and chronic infection, which is associated with poor health outcomes, increased morbidity and mortality, and substantial economic costs. Current treatment options for ACD are very limited. The discovery of the hypoxia-inducible factor-prolyl hydroxylase (HIF-PHD) pathway made it possible to develop novel therapeutic agents (such as hypoxia-inducible factor-prolyl hydroxylase inhibitor, HIF-PHI) to treat ACD by stabilizing HIF and subsequently promoting endogenous erythropoietin (EPO) production and iron absorption and utilization. Thus, HIF-PHIs appear to open a new door for the treatment of ACD patients with a novel mechanism. Here, we comprehensively reviewed the latest advancements in the application of HIF-PHIs in ACD. Specifically, we highlighted the key features of HIF-PHIs on ACD, such as stimulation of endogenous EPO, handling iron metabolism, inflammation-independent, and prolonging lifespan of red blood cells. In conclusion, the success of HIF-PHIs in the treatment of ACD may expand the therapeutic opportunity for other types of anemia beyond renal anemia.

Recent studies have revealed that CD8+ T cells can be activated via genetic upregulation of HIF-1α, thereby augmenting antitumor effector functions. HIF-1α upregulation can be attained by inhibiting HIF-prolyl hydroxylase (HIF-PH) under normoxic conditions, termed pseudohypoxia. This study investigated whether pseudohypoxia induced by HIF-PH inhibitors suppresses Microsatellite stable (MSS) colorectal cancer (CRC) by affecting tumor immune response.

The HIF-PH inhibitors Roxadustat and Vadadustat were utilized in this study. In vitro, we assessed the effects of HIF-PH inhibitors on human and murine colon cancer cell lines (SW480, HT29, Colon26) and murine T cells. In vivo experiments were performed with mice bearing Colon26 tumors to evaluate the effect of these inhibitors on tumor immune responses. Tumor and spleen samples were analyzed using immunohistochemistry, RT-qPCR, and flow cytometry to elucidate potential mechanisms.

HIF-PH inhibitors demonstrated antitumor effects in vivo but not in vitro. These inhibitors enhanced the tumor immune response by increasing the infiltration of CD8+ and CD4+ tumor-infiltrating lymphocytes (TILs). HIF-PH inhibitors induced IL-2 production in splenic and intratumoral CD4+ T cells, promoting T cell proliferation, differentiation, and immune responses. Roxadustat synergistically enhanced the efficacy of anti-PD-1 antibody for MSS cancer by increasing the recruitment of TILs and augmenting effector-like CD8+ T cells.

Pseudohypoxia induced by HIF-PH inhibitors activates antitumor immune responses, at least in part, through the induction of IL-2 secretion from CD4+ T cells in the spleen and tumor microenvironment, thereby enhancing immune efficacy against MSS CRC.

Objective Roxadustat, a hypoxia-inducible factor-prolyl hydroxylase inhibitor, increases the hemoglobin (Hb) levels in patients with chronic kidney disease (CKD). To date, limited clinical studies have focused on the excessive increase in the Hb levels in the early weeks after switching from erythropoiesis-stimulating agents (ESA) to roxadustat in adult non-dialysis patients. We conducted a retrospective study to examine whether early overshoot frequently occurs after switching to roxadustat. Methods This 8-week retrospective pilot study examined patients with anemic, non-dialyzed CKD who switched from ESA (darbepoetin or epoetin beta pegol) to roxadustat or continued ESA. The Hb levels >12.5 g/dL after starting our observation was defined as Hb overshoot. Patients: Twenty-three patients who switched to roxadustat (roxadustat group) and 63 who continued ESA (ESA group) were included. Results The baseline median estimated glomerular filtration rate and mean Hb levels were 15.7 mL/min/1.73 m2 and 10.77 g/dL in roxadustat group and 15.2 mL/min/1.73 m2 and 10.64 g/dL in ESA group, respectively. Eight patients (34.8%) in the roxadustat group and two patients (3.2%) in the ESA group had Hb overshoot within the 8-week visit [odds ratio: 20.2 (95% confidence interval 3.13-130.0, p<0.01) in the background adjusted model]. Among the patients with Hb overshoot in the roxadustat group, the Hb levels were maintained close to baseline 4 weeks after roxadustat discontinuation. A younger age and higher baseline Hb and Hct levels were risk factors for Hb overshoot. Conclusion Hb overshoot was frequently observed in patients switched to roxadustat. Clinicians should be aware of Hb overshoot and emphasize the importance of early Hb level checks.

Anaemia is common in chronic kidney disease (CKD) encompassing non-dialysis dependent CKD (NDD-CKD) and dialysis dependent CKD (DD-CKD); people on peritoneal dialysis (PD) and haemodialysis (HD); and kidney transplant recipients (KTR). Iron deficiency and erythropoietin deficiency are the most common causes of anaemia in people with CKD, especially those requiring kidney replacement therapy (KRT). The Renal National Service Framework and National Institute for Health and Clinical Excellence in the UK, and Kidney Disease Improving Global Outcomes (KDIGO), all advocate treatment of anaemia in people with CKD. Blood transfusions are infrequently required, and newer therapies such as Hypoxia-Inducible Factor (HIF-PHI) stabilisers are now in current use. This guideline provides evidence based graded practice guidance on the use of iron; comments on iron deficiency without anaemia in people with CKD; provide further information on anaemia management in people with a transplant and provide guidance in the use of the new HIF-PHI drugs. It also provides audit and research recommendations.

Different starting doses of roxadustat are used for treating anemia in chronic kidney disease (CKD). We tested the noninferiority of weight-based lower starting dose compared with standard starting dose roxadustat for anemia in stage 3 to 5 CKD without dialysis.

Patients were randomized (1:1) and stratified by CKD stage to receive weight-based standard (< 60 kg: 70 mg 3 times per week [TIW]; ≥ 60 kg: 100 mg TIW) or 1-step-lower (< 60 kg: 50 mg TIW; ≥ 60 kg: 70 mg TIW) roxadustat starting dose for 16 weeks. The primary endpoint was mean hemoglobin change from baseline over weeks 12 to 16. The secondary endpoints included the proportion achieving hemoglobin 100 to 120 g/l, hemoglobin variability, and rescue therapy.

Overall, 254 patients were randomized. The mean (SD) baseline hemoglobin was 89.88 (6.90) g/l. Most patients had stage 4 (39.0%) or stage 5 (40.2%) CKD. Mean hemoglobin increased from baseline at weeks 12 to 16 (lower: 21.57 g/l; standard: 26.35 g/l), but noninferiority was not met. A comparable proportion achieved hemoglobin of 100 to 120 g/l (lower: 46.0%; standard: 47.2%). The hemoglobin increase was comparable in CKD stage 3 to 4, but less with the lower dose in CKD stage 5 (17.28 vs. 26.71 g/l). The lower dose exhibited a lower hemoglobin rate of change (lower: 2.917; standard: 3.376) and less drug exposure. Drug-related adverse event rates were comparable.

The proportion of patients who achieved the hemoglobin target was comparable between the doses. The lower starting dose had less hemoglobin fluctuation and is recommended for stage 3 to 4 CKD.

Patients with chronic kidney disease (CKD) are at a significantly increased risk of stroke and experience worse stroke outcomes and higher mortality. CKD exacerbates stroke risk and severity through a complex interplay of systemic inflammation, oxidative stress, and impaired clearance of uremic toxins, leading to neuroinflammation and microglial activation. Current acute ischemic stroke treatments, while effective in the general population, do not adequately address CKD-specific mechanisms, limiting their efficacy in this high-risk population. Prolyl hydroxylase domain (PHD) inhibitors have shown promise in treating anemia associated with CKD and may offer cerebroprotective benefits. However, the effects of PHD2 inhibition on long-term sensorimotor outcomes and the underlying mechanisms in mice with CKD remain largely unknown. Here, we investigated the impact of CKD on stroke severity and assessed the therapeutic potential of desidustat, a PHD inhibitor, in improving stroke outcomes. Using an adenine-induced CKD mouse model, we demonstrated that CKD exacerbated stroke-induced long-term sensorimotor deficits, increased neuroinflammation, and impaired microglial efferocytosis via dysregulation of the ADAM17-MerTK axis. Desidustat treatment in mice with CKD significantly improved long-term sensorimotor functional outcomes and reduced post-stroke neuroinflammation while enhancing microglial efferocytosis by reducing ADAM17 and enhancing microglial MerTK expression. In vitro studies using human-induced microglia-like cells further confirmed the ability of desidustat to enhance efferocytosis of apoptotic neurons by reducing the cleavage of MerTK. These findings suggest that desidustat may serve as a novel therapeutic strategy for improving stroke outcomes in patients with CKD, a population at high risk for stroke and poor functional recovery.

Anaemia is a common comorbidity in patients with chronic kidney disease (CKD) and heart failure (HF). Roxadustat has been approved for the treatment of anaemia in patients with CKD. However, its efficacy and safety in treating anaemia in patients with both CKD and HF remain unclear. We conducted a retrospective study with propensity score matching (PSM) to evaluate the efficacy and safety of roxadustat in this population.

This retrospective study enrolled patients diagnosed with HF comorbid with CKD and anaemia. The patients were divided into two groups: a roxadustat group and a control group. One-to-one PSM was used to balance baseline characteristics between the groups. The primary endpoint was the change in haemoglobin (Hb) at week 8. Secondary endpoints included Hb response, changes in haematocrit, iron parameters, echocardiographic parameters, B-type natriuretic peptides and lipid levels. Exploratory endpoints were mortality and rehospitalization rates over 30 days-2 years. Safety endpoints included the incidence of hyperkalaemia, liver damage and thrombotic events.

A total of 1055 patients were screened. After PSM, 206 patients were included. Baseline characteristics were comparable between the matched cohorts. At week 8, the roxadustat group experienced a greater increase in Hb than the control group, with a difference of 0.8 g/dl (95% confidence interval 0.3-1.3; P = .003). The roxadustat group also demonstrated a higher Hb response (60.2% versus 28.2%; P < .001) and a greater increase in haematocrit (4.7 ± 0.9% versus 2.8 ± 0.6%; P = .008) than the control group. No significant differences were observed for other secondary endpoints. Thrombotic events were similar between the two groups and there were no differences in the risks of mortality or rehospitalization.

Roxadustat was effective in correcting and maintaining Hb levels in patients with anaemia, HF and CKD. It did not increase thrombotic and other adverse events, mortality or rehospitalization risks, making it a promising treatment option for anaemia in this population.

Hematopoietic stem cell (HSC) mobilization is often difficult to achieve in patients suffering from multiple myeloma and non-Hodgkin's lymphoma. Granulocyte-colony stimulating factor (G-CSF) therapy alone has often not led to the desired outcomes. Herein, we describe the discovery of 7-cyclohexyl-4-hydroxy-8-oxo-N-(pyridazin-4-ylmethyl)-7,8-dihydro-2,7-naphthyridine-3-carboxamide 13, a hypoxia-inducible factor prolyl hydroxylase (HIF-PH) inhibitor, which was discovered by focusing on drug-like properties. Building on a previous discovery that HIF-PH inhibitors can enhance HSC mobilization in combination with G-CSF, we optimized 13 to exhibit high PHD2 potency, improved solubility, and an optimized PK profile. 13 was effective at enhancing G-CSF-induced HSC mobilization in mice at a dose of 2 mg/kg.

The COVID-19 pandemic has made treating renal anemia in chronic kidney disease (CKD) patients undergoing peritoneal dialysis (PD) difficult. The current study aims to compare roxadustat with erythropoiesis-stimulating agents (ESAs) during the COVID-19 pandemic.

We conducted a single-center, retrospective study during the COVID-19 outbreak in China, from December 7, 2022, to January 31, 2023. The study involved patients undergoing PD who were divided based on the medication used to treat renal anemia; the roxadustat group (n = 34) and the ESAs group (n = 120). We analyzed the effectiveness of treating anemia, cost, medication adherence, and clinical outcomes related to COVID-19. Patients were followed up for 9 months.

The baseline of hemoglobin levels was (110.03 ± 1.71 g/L in the roxadustat and 110.1 ± 1.52 g/L in the ESAs groups, respectively), after 9 months of inspections, the levels of hemoglobin were (121.26 ± 2.03 g/L in the roxadustat and 118.49 ± 1.35 g/L in the ESAs groups, respectively). The roxadustat subgroup analysis indicated that total cholesterol and low-density lipoprotein levels in the roxadustat group decreased from baseline in subjects not receiving statins (3.39 ± 0.12 vs. 4.2 ± 0.21 mmol/L and 2.21 ± 0.23 vs. 3.65 ± 0.37 mmol/L, P < 0.05). The Morisky score of the roxadustat group was higher [7 (5, 8) vs. 6 (4, 8), P < 0.01]. The drug cost of the roxadustat group was higher, but another additional cost for correcting anemia was significantly reduced. The infection rate of COVID-19 and the mortality rate caused by COVID-19 were lower in roxadustat group.

During the COVID-19 pandemic, both roxadustat and ESAs effectively improved renal anemia in PD patients, however, the roxadustat group experienced less additional costs for anemia correction and better medication compliance.

Roxadustat is a novel hypoxia- inducible factor-prolyl hydroxylase inhibitor(HIF-PHI) used to treat anemia in chronic kidney disease (CKD) patients. It has been reported that roxadustat can slow down kidney damage and delay the development of kidney fibrosis. Anemia and iron deficiency are often associated with the vast majority CKD patients, and insufficient available iron or total iron storage is often the most common cause of anemia and ESAs resistance in CKD patients. The role of iron availability in the pathogenesis of anemia in chronic kidney disease has received increasing attention.

To explore whether combined roxadustat and polysaccharide-iron complex (PIC) is more successful than standalone roxadustat, the appropriate iron supplement dosage and mechanism of roxadustat in the treatment of CKD.

Healthy male Sprague Dawley rats were randomly divided into two groups: the control (NC) group which were sham-operated and the CKD group. The CKD group was given an adenine diet for three weeks after right unilateral nephrectomy and further divided into 6 groups: the CKD only, CKD + PIC, CKD + Roxa, CKD + PIC (25 mg/kg) + Roxa, CKD + PIC (50 mg/kg) + Roxa, and CKD + PIC (75 mg/kg) + Roxa groups. The sham-operated rats receiving only standard diet served as the control group. Roxadustat were administrated intragastrically at 10 mg/kg thrice per week in groups with Roxa. The hemoglobin (Hb), reticulocyte hemoglobin equivalent (RET-He), reticulocyte % (RET%), plasma urea nitrogen (BUN), plasma creatinine (Cr), serum iron (SI), Total iron binding capacity (TIBC), serum hepcidin-25, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interleukin-1β (IL- 1β), and High mobility group protein B1 (HMGB1) levels of each group of rats were assessed. Masson staining was used to evaluate renal fibrosis, and quantitative real-time Polymerase Chain Reaction (RT-PCR) was used to detect the mRNA expression of alpha-smooth muscle actin (α-SMA) and Fibronectin (Fn) in rat renal tissues to further evaluate renal fibrosis.

Level of Hb in the CKD + PIC (75 mg/kg) + Roxa group increased the fastest, roxadustat combined with PIC in the treatment of renal anemia was significantly more effective than Roxadustat or PIC alone. On day 105, in the CKD + PIC (75 mg/kg) + Roxa group, there was a significant decrease in BUN and Cr levels compared to the CKD only group (p < 0.05). Roxadustat reduces the level of hepcidin, IL-6, TNF-α, IL-1β and HMGB1in CKD rats. (p < 0.05). Roxadustat alleviates renal fibrosis in CKD rats (p < 0.05).

HIF-PHI combined with iron supplement (Roxadustat combined with PIC) has an improved effect on the treatment of renal anemia, and early administration of sufficient iron enables the Hb to rise rapidly. Early administration of adequate dose of PIC is necessary for renal anemia. HIF-PHI can improve iron metabolism, alleviate the microinflammatory state, alleviate renal fibrosis and plays a beneficial role in the treatment of renal fibrosis in CKD rats.

Liver fibrosis is characterized by excessive deposition of extracellular matrix due to chronic inflammation of the liver. Hepatic stellate cells (HSCs) become activated and produce increased amounts of extracellular matrix. Loss of HIF-prolyl-hydroxylase 1 (PHD1) attenuates HSC activation and fibrotic tissue remodeling in a murine model of biliary liver fibrosis. Herein, the protective effect of PHD1 deficiency (PHD1-/-) in an additional (toxic) model of liver fibrosis was validated and the effect of dimethyloxalylglycine (DMOG), a pan-HIF-prolyl-hydroxylase inhibitor, on the development of liver fibrosis, was evaluated. Liver fibrosis was induced utilizing carbon tetrachloride in wild-type (WT) and PHD1-/- mice treated with either vehicle or DMOG. To assess fibrosis development, expression of profibrotic genes in the livers was analyzed by Sirius red staining. When compared with WT mice, PHD1-/- mice developed less-severe liver fibrosis. DMOG treatment did not prevent this liver fibrosis. PHD1-/- mice had fewer α-SMA+ cells and less macrophage infiltration compared with WT mice. Expression of profibrogenic and proinflammatory genes was reduced in livers from carbon tetrachloride-exposed PHD1-/- mice. In vitro analyses of PHD1-deficient human HSCs revealed attenuated mRNA levels of profibrotic genes, as well as impaired migration and invasion. Although PHD1 deficiency attenuated activation of HSCs, pharmacologic PHD inhibition did not ameliorate fibrosis development. These data indicate that selective PHD1 inhibitors could prove effective in preventing and treating liver fibrosis.

Most eukaryotes require oxygen for their survival and, with increasing multicellular complexity, oxygen availability and delivery rates vary across the tissues of complex organisms. In humans, healthy tissues have markedly different oxygen gradients, ranging from the hypoxic environment of the bone marrow (where our haematopoietic stem cells reside) to the lungs and their alveoli, which are among the most oxygenated areas of the body. Immune cells are therefore required to adapt to varying oxygen availability as they move from the bone marrow to peripheral organs to mediate their effector functions. These changing oxygen gradients are exaggerated during inflammation, where oxygenation is often depleted owing to alterations in tissue perfusion and increased cellular activity. As such, it is important to consider the effects of oxygenation on shaping the immune response during tissue homeostasis and disease conditions. In this Review, we address the relevance of both physiological oxygenation (physioxia) and disease-associated hypoxia (where cellular oxygen demand outstrips supply) for immune cell functions, discussing the relevance of hypoxia for immune responses in the settings of tissue homeostasis, inflammation, infection, cancer and disease immunotherapy.

Pegmolesatide has been recently approved for treating anemia in chronic kidney disease (CKD) patients in China. We presented the results of the pivotal study conducted in patients with nondialysis-dependent (NDD)-CKD with anemia.

This randomized, active-controlled, open-label, noninferiority phase 3 study was conducted across 38 centers in China. Eligible patients were randomly assigned to receive subcutaneous injection of pegmolesatide in the upper arm once every 4 weeks or epoetin alfa weekly or biweekly, with doses adjusted to maintain hemoglobin (Hb) level of 100 to 120 g/l. The primary outcome was the mean change in Hb level from the baseline during the efficacy evaluation period. Noninferiority of pegmolesatide to epoetin alfa was established if the lower limit of the 2-sided 95% confidence interval (CI) was ≥ -10 g/l.

A total of 173 patients received at least 1 dose of pegmolesatide (115 patients) or epoetin alfa (58 patients). During the efficacy evaluation period, the mean change in Hb from baseline level was 19.2 g/l in the pegmolesatide group and 15.4 g/l in the epoetin alfa group with a between-group difference of 3.8 g/l (95% CI: 0.7-6.9). The incidence of adverse events (AEs) and serious AEs (SAEs) were similar between groups, with hypertension being the most reported AE related to the study drug. No drug-related hypersensitivity reactions or fatal events were observed.

Pegmolesatide demonstrated comparable efficacy to epoetin alfa in elevating and maintaining Hb levels in patients with NDD-CKD with anemia without new safety concerns (ClinicalTrials.gov identifier: NCT03903809).

Translocation renal cell carcinoma (tRCC) is an aggressive subtype of kidney cancer driven by TFE3 gene fusions, which act via poorly characterized downstream mechanisms. Here we report that TFE3 fusions transcriptionally rewire tRCCs toward oxidative phosphorylation (OXPHOS), contrasting with the highly glycolytic nature of most other renal cancers. Reliance on this TFE3 fusion-driven OXPHOS programme renders tRCCs vulnerable to NADH reductive stress, a metabolic stress induced by an imbalance of reducing equivalents. Genome-scale CRISPR screening identifies tRCC-selective vulnerabilities linked to this metabolic state, including EGLN1, which hydroxylates HIF-1α and targets it for proteolysis. Inhibition of EGLN1 compromises tRCC cell growth by stabilizing HIF-1α and promoting metabolic reprogramming away from OXPHOS, thus representing a vulnerability for OXPHOS-dependent tRCC cells. Our study defines tRCC as being dependent on a mitochondria-centred metabolic programme driven by TFE3 fusions and nominates EGLN1 inhibition as a therapeutic strategy in this cancer.

Over-proliferation of mesangial cells (MCs) is one of the main pathological changes in the early stages of diabetic kidney disease (DKD). Roxadustat, an oral hypoxia-inducible factor (HIF) prolyl hydroxylase inhibitor, is widely studied in different models of kidney disease. Whether roxadustat has beneficial effect on the proliferation of MCs and DKD remains unknown.

The optimal concentration of roxadustat for inhibiting MC proliferation was determined using CCK-8 and colony formation assays. Changes in the cell cycle were detected using flow cytometry, and changes in cell cycle-related proteins were screened using quantitative reverse transcription polymerase chain reaction. Reverse experiments were applied using Trp53-/- cell line. Co-immunoprecipitation was used to verify the interaction between HIF-1α and p53 and predict sites of interaction. Finally, a corresponding in vivo verification was performed.

Optimal concentrations of high glucose (30 mM) and roxadustat (100 μM) were established. Roxadustat showed anti-proliferation effect on MCs through S-phase arrest. HIF-1α/p53/p21 and downstream cyclins (cyclin A1, cyclin A2, and cyclin E1) showed corresponding changes. A reverse experiment confirmed that HIF-1α affected cell cycle and proliferation through p53, and co-immunoprecipitation results showed a interaction between HIF-1α and p53. Molecular docking predicted the possible interaction between Lys328, Pro332, Arg245, and Lys251 of HIF-1α and Ala222, Tyr226, Glu225, and Asp265 of p53, respectively. Finally, animal experiments demonstrated similar effect of roxadustat in db/db mice.

Roxadustat regulates and inhibits cell proliferation of MCs via the HIF-1α/p53/p21 pathway. This may be a potential therapeutic target in the early stages of diabetic kidney disease.

Erythropoietin (EPO) is a key regulator of erythrocyte production, promoting erythroid progenitor cell survival, division, and differentiation in the fetal liver and adult bone marrow. Mice lacking EPO or its receptor (EPOR) die in utero due to severe anemia. Beyond hematopoiesis, EPO influences non-hematopoietic tissues, including glucose and fat metabolism in adipose tissue, skeletal muscle, and the liver. EPO is used to treat anemia associated with chronic kidney disease clinically and plays a role in maintaining metabolic homeostasis and regulating fat mass. EPO enhances lipolysis while inhibiting lipogenic gene expression in white adipose tissue, brown adipose tissue, skeletal muscle, and the liver, acting through the EPO-EPOR-RUNX1 axis. The non-erythroid EPOR agonist ARA290 also improves diet-induced obesity and glucose tolerance providing evidence for EPO regulation of fat metabolism independent of EPO stimulated erythropoiesis. Therefore, in addition to the primary role of EPO to stimulate erythropoiesis, EPO contributes significantly to EPOR-dependent whole-body metabolic response.

Moderate/severe anemia [hemoglobin (Hb) < 10 g/dL] is recommended to be treated in patients with renal anemia. However, the optimal therapeutic target for Hb levels in patients with heart failure (HF) is unknown. This study aimed to investigate the impact of severity of anemia, especially moderate/severe anemia, associated with renal dysfunction (RD: eGFR < 60 mL/min/1.73 m2) in HF patients. We analyzed 1,608 HF patients from the Japanese Cardiac Registry of Heart Failure in Cardiology (JCARE-CARD) database. Patients were classified based on the severity of admission anemia in the presence/absence of RD. Patients with RD and anemia were older, more likely to be female, and had a history of HF admission. The composite outcome was higher in RD and moderate/severe anemia (adjusted hazard ratio:2.120, 95% CI:1.559-2.881, p < 0.001) compared to RD and non/mild anemia (Hb ≥ 10 g/dL), non-RD and moderate/severe anemia, and non-RD and non/mild anemia (reference). During hospitalization, 6% and 10% of patients had improving and worsening RD and/or moderate/severe anemia, respectively. These status changes were associated with the post-discharge outcomes in HF patients. Moderate/severe anemia has a prognostic impact in HF patients with RD and may be an appropriate therapeutic target in HF.

Renal anemia stems mainly from chronic inflammation with elevated hepcidin levels, iron deficiency, and reduced red blood cell lifespan. Inadequate erythropoietin (EPO) production, worsened kidney function, leads to symptoms such as low energy, fatigue, and impaired physical function, significantly affecting patients' quality of life. We conducted a comprehensive search across electronic databases including PubMed, Embase, Cochrane Library, Chinese National Knowledge Infrastructure, Airiti library, and Wanfang, to compile recent clinical trials and pilot studies on conventional and complementary alternative medicine approaches for renal anemia. This discussion focuses on the hypoxia-inducible factor prolyl hydroxylase domain (HIF-PHD) axis theory, from lab research to clinical applications. It explores non-extracorporeal treatments for renal anemia, including pharmaceutical interventions, dietary strategies, and complementary and alternative medicine (CAM). The article details the effects of Roxadustat, Ferumoxytol, and Epodion. Clinical studies show that modulating the gut microbiome can reduce inflammation and improve renal anemia. Clinical trials suggest that CAM therapy can improve renal anemia through mechanisms such as enhanced iron metabolism, anti-inflammatory effects, reduced hepcidin levels, and increased EPO and HIF expressions. By synthesizing this information, the review aims to furnish valuable insights and treatment recommendations aimed at ameliorating renal anemia in individuals grappling with chronic kidney disease.

Renal anemia is a common complication among patients with non-dialysis chronic kidney disease (ND-CKD), and there remains an unmet need for more efficient and convenient daily oral medications to improve patient outcomes. This study aimed to evaluate the efficacy and safety of enarodustat, a hypoxia-inducible factor-prolyl hydroxylase inhibitor, in treating anemia for ND-CKD patients.

This phase 3 study was conducted at 48 centers across China, enrolling 156 ND-CKD patients. Participants were randomly randomized in a 2:1 ratio to receive either enarodustat or placebo for an initial 8-week double-blind period, followed by a 16-week open-label period during which all patients received enarodustat.

The primary endpoint was the mean change in hemoglobin (Hb) levels from baseline to the average level during weeks 7-9. Secondary endpoints focused on Hb concentration or treatment pattern, while exploratory endpoints assessed iron metabolism-related parameters. The mean (±SD) change in Hb levels from baseline to weeks 7-9 was 15.99 (±9.46) g/L in the enarodustat group, compared to -0.14 (±8.08) g/L in the placebo group, resulting in a mean difference of 16.00 (±1.54) g/L (p < 0.001). During weeks 7-9, 85.3% of patients in the enarodustat group achieved Hb levels ≥100 g/L with 86.0% maintaining this level during weeks 21-25. In the first 4 weeks, the Hb increased by 11.82 (±9.56) g/L in the enarodustat group. By week 9, the mean change in hepcidin level was -42.94 (±37.56) ng/mL in the enarodustat group, compared to +4.58 (±33.34) ng/mL in the placebo group. Enarodustat also improved other iron-related parameters and reduced the need for iron supplements. The safety profile of enarodustat was well tolerable with adverse events comparable to those of the placebo.

Enarodustat effectively corrected renal anemia with a manageable safety profile. Its once-daily oral administration offers convenience that may enhance the adherence. Enarodustat shows the potential as a promising therapy for anemic patients with ND-CKD.

Germinal centers where B cells undergo clonal expansion and antibody affinity maturation are hypoxic microenvironments. However, the function of hypoxia-inducible factor (HIF)-1α in immunoglobulin production remains incompletely characterized. Here, we demonstrated that B cells lacking HIF-1α exhibited significantly lower glycolytic metabolism and impaired IgA production. Loss of HIF-1α in B cells affects IgA-producing B-cell differentiation and exacerbates dextran sodium sulfate (DSS)-induced colitis. Conversely, promoting HIF-1α stabilization via a PHD inhibitor roxadustat enhances IgA class switching and alleviates intestinal inflammation. Mechanistically, HIF-1α facilitates IgA class switching through acetyl-coenzyme A (acetyl-CoA) accumulation, which is essential for histone H3K27 acetylation at the Sα region. Consequently, supplementation with acetyl-CoA improved defective IgA production in Hif1a-deficient B cells and limited experimental colitis. Collectively, these findings highlight the critical importance of HIF-1α in IgA class switching and the potential for targeting the HIF-1α-dependent metabolic‒epigenetic axis to treat inflammatory bowel diseases and other inflammatory disorders.

Hypoxia-inducible factors (HIF) regulate gene transcription, which aids hypoxia adaptation while promoting renal fibrosis. Non-transferrin-bound iron (NTBI) is a catalytic form of iron that can lead to oxidative damage. However, NTBI in cat biofluids has rarely been evaluated.

We assessed cat plasma and urine HIF-1α (pHIF-1α/uHIF-1α) concentrations and urine NTBI (uNTBI) concentrations to investigate their relationship with chronic kidney disease (CKD) severity.

pHIF-1α and uHIF-1α concentrations were measured using commercial ELISA kits, while uNTBI concentrations were detected by inductively coupled plasma mass spectrometry.

Healthy cats (n = 35) and cats with CKD (n = 84) formed the study cohorts. pHIF-1α concentrations increased from 9.48 pg./mL (median) in the healthy cohort to 11.42 pg./mL in early-stage CKD cats but decreased to 8.50 pg./mL in late-stage CKD cats. uHIF-1α concentrations gradually decreased with a significant difference between the control group (44.61 pg./mL) and the late-stage CKD group (36.79 pg./mL, p < 0.001). Cats with proteinuria had significantly higher uNTBI concentrations (35.61 ppb) than non-proteinuric cats (25.13 ppb, p = 0.019). Finally, the concentrations of pHIF-1α and uHIF-1α were positively correlated independent of renal function.

Overall, pHIF-1α and uHIF-1α concentrations are lower in advanced CKD cats, while uNTBI concentrations are significantly higher in proteinuric cats.

Hypoxia Inducible transcription Factors (HIFs) are central to the metazoan oxygen-sensing response. Under low oxygen conditions (hypoxia), HIFs are stabilised and govern an adaptive transcriptional programme to cope with prolonged oxygen starvation. However, when oxygen is present, HIFs are continuously degraded by the proteasome in a process involving prolyl hydroxylation and subsequent ubiquitination by the Von Hippel Lindau (VHL) E3 ligase. The essential nature of VHL in the HIF response is well established but the role of other enzymes involved in ubiquitination is less clear. Deubiquitinating enzymes (DUBs) counteract ubiquitination and provide an important regulatory aspect to many signalling pathways involving ubiquitination. In this review, we look at the complex network of ubiquitination and deubiquitination in controlling HIF signalling in normal and low oxygen tensions. We discuss the relative importance of DUBs in opposing VHL, and explore roles of DUBs more broadly in hypoxia, in both VHL and HIF independent contexts. We also consider the catalytic and non-catalytic roles of DUBs, and elaborate on the potential benefits and challenges of inhibiting these enzymes for therapeutic use.

This study is intended to explore the effect of hypoxia-inducible factor-1α (HIF-1α) activation on lipid accumulation in the diabetic kidney. A type 1 diabetic rat model was established by STZ intraperitoneal injection. Cobalt chloride (CoCl2) and YC-1 were used as the HIF-1α activator and antagonist, respectively. CoCl2 treatment significantly increased HIF-1α expression, accelerated lipid deposition, and accelerated tubular injury in diabetic kidneys. In vitro, CoCl2 effectively stabilized HIF-1α and increased its transportation from the cytoplasm to the nucleus, which was accompanied by significantly increased lipid accumulation in HK-2 cells. Furthermore, results obtained in vivo showed that HIF-1α protein expression in the renal tubules of diabetic rats was significantly downregulated by YC-1 treatment. Meanwhile, lipid accumulation in the tubules of the DM + YC-1 group was markedly decreased in comparison to the DM + DMSO group. Accordingly, PAS staining revealed that the pathological injury caused to the tubular epithelial cells was alleviated by YC-1 treatment. Furthermore, the blood glucose level, urine albumin creatinine ratio, and NAG creatinine ratio in the DM + YC-1 group were significantly decreased compared to the DM + DMSO group. Moreover, the protein expression levels of transforming growth factor β1 (TGF-β1) and connective tissue growth factor (CTGF) in diabetic kidneys were decreased by YC-1 treatment. Our findings demonstrate that the activation of HIF-1α contributed to interstitial injury in a rat model of diabetic nephropathy and that the underlying mechanism involved the induction of lipid accumulation.

Myelodysplastic syndromes/neoplasms (MDS) constitute a heterogeneous group of clonal hematopoietic disorders with extremely variable clinical features and outcomes. Management of MDS is largely based on risk stratification of patients into either lower-risk or higher-risk categories using the International Prognostic Scoring System-Revised and, more recently, on the Molecular International Prognostic Scoring System. Lower-risk MDS is often managed with the goal of ameliorating cytopenias and improving quality of life, while higher-risk MDS is treated with therapies aimed at extending survival and delaying progression to acute myeloid leukemia (AML). Therapeutic strategies in lower-risk MDS patients may consist of erythropoiesis stimulating agents, luspatercept, and lenalidomide for selected patients. Furthermore, imetelstat has recently been added to the FDA-approved therapeutic armamentarium for lower-risk MDS. In higher-risk MDS, monotherapy with hypomethylating agents continues to be the standard of care. While several novel hypomethylating agent combinations have and are being studied in large randomized phase 3 clinical trials, including the combination of azacitidine and venetoclax, no combination to date have improved overall survival to azacitidine monotherapy. Moreover, biomarker-directed therapies as well as immonotherapeutic approaches are currently being evaluated in early phase trials. Despite recent advancements, the lack of therapeutic agents, particularly after the failure of first line therapy in higher risk MDS, continues to be a major hurdle in the management of MDS. In this review, we discuss the current treatment landscape of MDS and provide an overview of novel agents currently in clinical development that have the potential to alter our current treatment paradigms.

This systematic review and meta-analysis were conducted to evaluate the cardiac and kidney-related adverse effects of roxadustat for the treatment of anemia in CKD patients. 18 trials with a total of 8806 participants were identified for analysis. We employed a fixed-effects model for analysis. The pooled result revealed no significant difference in the risk of occurrence of cardiac disorders when comparing CKD patients receiving roxadustat with the placebo (RR = 1.049; CI [0.918 to 1.200]) or ESA (RR = 1.066; CI [0.919 to 1.235]), in both dialysis-dependent (DD) (RR = 1.094; CI [0.925 to 1.293]) or non-dialysis-dependent (NDD) (RR = 1.036; CI [0.916 to 1.171]) CKD patients. No significant difference was observed in the risk of kidney-related adverse events when comparing roxadustat with the placebo (RR = 1.088; CI [0.980 to 1.209]) or ESA (RR = 0.968; CI [0.831 to 1.152]), in DD (RR = 2.649; CI [0.201 to 34.981]) or NDD (RR = 1.053; CI [0.965 to 1.149]) CKD patients. A high risk of hyperkalemia was observed in the roxadustat group in DD (RR = 0.939; CI [0.898 to 0.981]). Incidence of hypertension was higher in the roxadustat for NDD patients (RR = 1.198; CI [1.042 to 1.377]), or compared to the placebo (RR = 1.374; CI [1.153 to 1.638]). In summary, the risk of cardiac or kidney-related events observed in the roxadustat was not significantly increase whether in DD or NDD patients. However, attention must be paid to the occurrence of hyperkalemia for DD patients and hypertension in NDD patients using roxadustat.

Acute kidney injury (AKI) is associated with a high mortality rate. Pathologically, renal ischemia/reperfusion injury (RIRI) is one of the primary causes of AKI, and hypoxia-inducible factor (HIF)-1α may play a defensive role in RIRI. This study assessed the role of hypoxia-inducible factor 1α (HIF-1α)-mediated mitophagy in protection against RIRI in vitro and in vivo. The human tubular cell line HK-2 was used to assess hypoxia/reoxygenation (H/R)-induced mitophagy through different in vitro assays, including western blotting, immunofluorescence staining, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL), and reactive oxygen species (ROS) measurement. Additionally, a rat RIRI model was established for evaluation by renal histopathology, renal Doppler ultrasound, and transmission electron microscopy to confirm the in vitro data. The selective HIF-1α inhibitor LW6 reduced H/R-induced mitophagy but increased H/R-induced apoptosis and ROS production. Moreover, H/R treatment enhanced expression of the FUN14 domain-containing 1 (FUNDC1) protein. Additionally, FUNDC1 overexpression reversed the effects of LW6 on the altered expression of light chain 3 (LC3) BII and voltage-dependent anion channels as well as blocked the effects of HIF-1α inhibition in cells. Pretreatment of the rat RIRI model with roxadustat, a novel oral HIF-1α inhibitor, led to decreased renal injury and apoptosis in vivo. In conclusion, the HIF-1α/FUNDC1 signaling pathway mediates H/R-promoted renal tubular cell mitophagy, whereas inhibition of this signaling pathway protects cells from mitophagy, thus aggravating apoptosis, and ROS production. Accordingly, roxadustat may protect against RIRI-related AKI.

Hypoxia-inducible factor prolyl hydroxylase (HIF-PH) inhibitors are a new class of agents for the treatment of anemia in chronic kidney disease (CKD). Unlike traditional treatments such as erythropoiesis-stimulating agents (ESAs), HIF-PH inhibitors are orally administered drugs and may increase endogenous erythropoietin and improve iron homeostasis. However, a significant concern is their possible side effect on blood pressure. The current mini-review summarizes the data of 26 randomized controlled (placebo or ESAs) trials on six different HIF-PH inhibitors with regard to their potential influence on blood pressure and hypertension in the management of anemia in CKD. Overall, the use of HIF-PH inhibitors was associated with a higher risk of hypertension than placebo (pooled risk ratio 1.36, 95% confidence interval [CI] 1.16-1.59), but a lower risk of hypertension than ESA treatment (pooled risk ratio 0.92, 95% CI 0.86-0.98), especially in CKD patients not undergoing dialysis (pooled risk ratio 0.85, 95% CI 0.73-0.98). This review highlights the importance of blood pressure monitoring during the treatment of HIF-PH inhibitors, especially out-of-office blood pressure measurement.

Recombinant human erythropoietin (rHuEPO) is commonly used to treat anemia associated with chronic kidney disease (CKD). EPO-induced Pure Red Cell Aplasia (PRCA) is a rare condition of profound anemia with EPO treatment. Upon finding the development of EPO-induced PRCA, the treatment requires immediate withdrawal of EPO therapy and initiate new treatments with immunosuppression or renal transplantation. Anti-EPO antibody assay is not always positive in EPO-induced PRCA. Here, we report a case on the sudden development of PRCA in a hemodialysis patient receiving EPO and how we treated the condition successfully with cyclosporine and subsequently maintained the hemoglobin with Roxadustat, a hypoxia-inducible factor prolyl hydroxylase inhibitor (HIF-PHI). Even though the anti-EPO antibody was negative by Enzyme Linked Immunosorbent Assay (ELISA) in our case, the clinical course, the markedly reduced reticulocyte count < 10,000/μL, the bone marrow (BM) biopsy revealing reduced erythroblasts, and its subsequent response to cyclosporine, were similar to EPO-induced PRCA. The clinical picture of EPO-induced PRCA, the limitation of the EPO-neutralizing antibody (Ab) assay, and treatment strategies were discussed.

The unique property of the pulmonary circulation to constrict in response to hypoxia, rather than dilate, brings advantages in both health and disease. Hypoxic pulmonary vasoconstriction (HPV) acts to optimise ventilation-perfusion matching - this is important clinically both in focal disease (such as pneumonia) and in one-lung ventilation during anaesthesia for thoracic surgery. However, during global hypoxia such as that encountered at high altitude, generalised pulmonary vasoconstriction can lead to pulmonary hypertension. There is now a growing body of evidence that links the hypoxia-inducible factor (HIF) pathway and pulmonary vascular tone - in both acute and chronic settings. Genetic and pharmacological alterations to all key components of this pathway (VHL - von Hippel-Lindau ubiquitin E3 ligase; PHD2 - prolyl hydroxylase domain protein 2; HIF1 and HIF2) have clear effects on the pulmonary circulation, particularly in hypoxia. Furthermore, knowledge of the molecular biology of the prolyl hydroxylase enzymes has led to an extensive and ongoing body of research into the importance of iron in both HPV and pulmonary hypertension. This review will explore these relationships in more detail and discuss future avenues of research.

Roxadustat, an oral inhibitor of hypoxia-inducible factor prolyl hydroxylase domain enzymes, has been approved for the treatment of renal anemia. However, there is a lack of study on its pharmacokinetics in kidney transplant recipients (KTRs) with early posttransplant anemia (PTA). Therefore, the aim of this study is to elucidate the pharmacokinetic characteristics of roxadustat in KTRs with early PTA and optimize the dosing regimen.

A population pharmacokinetic (PopPK) analysis was performed based on 72-hour full concentration-time profiles collected from 52 Chinese KTRs. Covariates influencing exposure were assessed using stepwise covariate modelling. Monte Carlo simulations were conducted to recommend the dosing regimen for patients with different levels of covariates.

PopPK analysis showed that the concentration-time data can be fully described by a two-compartment model. Body weight (BW) and direct bilirubin (DBIL) levels significant affected the apparent clearance of roxadustat. Based on the established model and the estimated exposures of roxadustat by Monte Carlo simulations, a recommended dosing regimen for KTRs with early PTA at varying BW and DBIL levels were developed. Roxadustat at 100 mg three times weekly were suitable for the majority of KTRs with a DBIL level around 3 μmol/L and BW between 50 and 75 kg. The required dose may need to be increased with higher BW and lower DBIL levels, while decreased with lower BW and higher DBIL levels.

It was the first PopPK analysis of roxadustat in KTRs with early PTA, which provide a research basis for optimizing the dosing regimen.

FG-4592 is a hypoxia-inducible factor inhibitor that has been approved for therapeutic use in some countries. This class of compounds can increase the oxygen carrying capacity of the blood and thus have the potential to be used as performance enhancing agents in sports. The purpose of this study was to investigate the detection of FG-4592 and metabolites in equine plasma and mane hair following a multiple dose oral administration to two Thoroughbred racehorses, to identify the best analytical targets for doping control laboratories. Urine samples were also analysed, and the results compared to previously published urine data. Liquid chromatography-high resolution mass spectrometry was used for metabolite identification in urine and plasma. Liquid chromatography-tandem mass spectrometry was used for full sample analysis of urine, plasma and hair samples and generation of urine and plasma profiles. FG-4592 and a mono-hydroxylated metabolite were detected in plasma. FG-4592 was detected with the greatest abundance and gave the longest duration of detection, up to 312 h post-administration, and would be the recommended target in routine doping samples. FG-4592 was detected in all mane hair samples collected post-administration, up to 166 days following the final dose, showing extended detection can be achieved with this matrix. To the best of the authors' knowledge, this is the first report of FG-4592 and metabolites in equine plasma and hair samples. Urine results were consistent with the previously published data, with FG-4592 offering the best target for detection and longest detection periods.