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2.
Sci Rep ; 11(1): 8392, 2021 04 16.
Article in English | MEDLINE | ID: mdl-33863987

ABSTRACT

Leucyl-tRNA synthetase (LARS) is an enzyme that catalyses the ligation of leucine with leucine tRNA. LARS is also essential to sensitize the intracellular leucine concentration to the mammalian target of rapamycin complex 1 (mTORC1) activation. Biallelic mutation in the LARS gene causes infantile liver failure syndrome type 1 (ILFS1), which is characterized by acute liver failure, anaemia, and neurological disorders, including microcephaly and seizures. However, the molecular mechanism underlying ILFS1 under LARS deficiency has been elusive. Here, we generated Lars deficient (larsb-/-) zebrafish that showed progressive liver failure and anaemia, resulting in early lethality within 12 days post fertilization. The atg5-morpholino knockdown and bafilomycin treatment partially improved the size of the liver and survival rate in larsb-/- zebrafish. These findings indicate the involvement of autophagy in the pathogenesis of larsb-/- zebrafish. Indeed, excessive autophagy activation was observed in larsb-/- zebrafish. Therefore, our data clarify a mechanistic link between LARS and autophagy in vivo. Furthermore, autophagy regulation by LARS could lead to development of new therapeutics for IFLS1.


Subject(s)
Anemia/pathology , Autophagy , Leucine-tRNA Ligase/deficiency , Leucine/metabolism , Liver Failure/pathology , Zebrafish/growth & development , Anemia/enzymology , Anemia/etiology , Animals , Liver Failure/enzymology , Liver Failure/etiology , Zebrafish/metabolism
3.
FEBS J ; 288(13): 3978-3999, 2021 07.
Article in English | MEDLINE | ID: mdl-33410203

ABSTRACT

The MAP kinase p38α is associated with numerous processes in eukaryotes, and its elevated activity is a prominent feature of inflammatory diseases, allergies, and aging. Since p38α is a nodal component of a complex signaling network, it is difficult to reveal exactly how p38α contributes to disparate outcomes. Identification of p38α -specific effects requires activation of p38α per se in vivo. We generated a transgenic mouse model that meets this requirement by allowing inducible and reversible expression of an intrinsically active p38α molecule (p38αD176A+F327S ). p38α's activation across all murine tissues resulted in a significant loss of body weight and death of about 40% of the mice within 17 weeks of activation, although most tissues were unaffected. Flow cytometric analysis of the lungs and bronchoalveolar lavage fluid detected an accumulation of 'debris' within the airways, suggesting impaired clearance. It also revealed increased numbers of alternatively activated alveolar macrophages and myeloid-derived suppressor cells within the lung, pointing at suppression and resolution of inflammation. Blood count suggested that mice expressing p38αD176A+F327S suffer from hemolytic anemia. Flow cytometry of bone marrow revealed a reduced number of hematopoietic stem cells and abnormalities in the erythroid lineage. Unexpectedly, p38α's substrate MAPKAPK2, mitogen-activated protein kinase-activated protein kinase 2 was downregulated in mice expressing p38αD176A+F327S , suggesting that constitutive activity of p38α may impose pathological phenotypes by downregulating downstream components, perhaps via a feedback inhibition mechanism. In summary, this new mouse model shows that induced p38α activity per se is hazardous to mouse vitality and welfare, although pathological parameters are apparent only in blood count, bone marrow, and lungs.


Subject(s)
Anemia/genetics , Gene Expression Regulation, Enzymologic , Macrophages/metabolism , Mitogen-Activated Protein Kinase 14/genetics , Mutation , Myeloid-Derived Suppressor Cells/metabolism , Anemia/enzymology , Animals , Body Weight/genetics , Cytokines/blood , Cytokines/metabolism , Intracellular Signaling Peptides and Proteins/genetics , Intracellular Signaling Peptides and Proteins/metabolism , Macrophages/classification , Macrophages/immunology , Mice, Inbred C57BL , Mice, Knockout , Mice, Transgenic , Mitogen-Activated Protein Kinase 14/metabolism , Myeloid-Derived Suppressor Cells/immunology , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism , Substrate Specificity
4.
Am J Physiol Renal Physiol ; 320(2): F234-F242, 2021 02 01.
Article in English | MEDLINE | ID: mdl-33356956

ABSTRACT

Chronic kidney disease (CKD) is one of the most prominent diseases affecting our population today. According to the Factsheet published by Centers for Disease Control and Prevention (CDC), it effects approximately 15% of the total population in the United States in some way, shape, or form. Within the myriad of symptomatology associated with CKD, one of the most prevalent factors in terms of affecting quality of life is anemia. Anemia of CKD cannot be completely attributed to one mechanism or cause, but rather has a multifactorial origin in the pathophysiology of CKD. While briefly summarizing well-documented risk factors, this review, as a hypothesis, aims to explore the possible role of Na-K-ATPase and its signaling function [especially recent identified reactive oxygen species (ROS) amplification function] in the interwoven mechanisms of development of the anemia of CKD.


Subject(s)
Anemia/enzymology , Anemia/etiology , Renal Insufficiency, Chronic/complications , Signal Transduction/physiology , Sodium-Potassium-Exchanging ATPase/metabolism , Humans , Sodium-Potassium-Exchanging ATPase/genetics
5.
Pharmacol Res ; 159: 105020, 2020 09.
Article in English | MEDLINE | ID: mdl-32561478

ABSTRACT

Hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs) are a new class of oral medicines being developed for the treatment of anemia in chronic kidney disease (CKD) patients. This study aimed to compare the efficacy and safety of HIF-PHI vs epoetin and darbepoetin in CKD patients with anemia not undergoing dialysis. The PubMed, Embase, Cochrane Library, Web of Science, and clinicaltrials.gov databases were searched from inception to October 2019 for randomized controlled trials investigating different agents (six HIF-PHIs, epoetin, darbepoetin, and placebo) for treating CKD patients with anemia that did not undergo dialysis. The outcomes included a change in hemoglobin (Hb) levels and all-cause mortality. A total of 19 studies were included. Compared with the placebo, except for vadadustat (mean differences: 1.12, 95 % confidence interval [CI]: ‒0.11-2.35), the other drugs significantly increased Hb levels, with mean differences of 2.46 (95 % CI: 0.93-3.99) for desidustat, 1.81 (0.87-2.75) for enarodustat, 1.68 (0.64-2.72) for molidustat, 1.66 (0.89-2.44) for epoetin, 1.63 (0.69-2.56) for darbepoetin, 1.61 (0.99-2.22) for roxadustat, and 1.55 (0.74-2.36) for daprodustat. No differences were found in the Hb level elevations among these eight drugs. Compared with the placebo, there also was no significant association between the drugs and all-cause mortality (molidustat of RR, 0.39 [95 % CI, 0.06-2.59]; roxadustat, 0.40 (0.06-2.84); enarodustat, 0.33 (0.01-16.25); desidustat, 0.34 (0.01-17.00); epoetin, 0.50 (0.18-1.42); daprodustat, 0.54 (0.09-3.31); darbepoetin, 1.03 (0.65-1.65); and vadadustat, 1.43 (0.15-13.27)). No differences were observed in the all-cause mortality among the drugs. In conclusion, these HIF-PHIs are effective and relatively tolerant for treating anemia patients with CKD not undergoing dialysis. Further research should consider the limitations of our study to evaluate the value of these HIF-PHIs in clinical settings.


Subject(s)
Anemia/drug therapy , Darbepoetin alfa/therapeutic use , Enzyme Inhibitors/therapeutic use , Epoetin Alfa/therapeutic use , Hematinics/therapeutic use , Hemoglobins/metabolism , Hypoxia-Inducible Factor-Proline Dioxygenases/antagonists & inhibitors , Renal Insufficiency, Chronic/complications , Aged , Aged, 80 and over , Anemia/enzymology , Anemia/etiology , Anemia/mortality , Biomarkers/blood , Darbepoetin alfa/adverse effects , Enzyme Inhibitors/adverse effects , Epoetin Alfa/adverse effects , Female , Hematinics/adverse effects , Humans , Hypoxia-Inducible Factor-Proline Dioxygenases/metabolism , Male , Middle Aged , Network Meta-Analysis , Randomized Controlled Trials as Topic , Renal Insufficiency, Chronic/mortality , Risk Assessment , Risk Factors , Time Factors , Treatment Outcome
6.
Sheng Li Xue Bao ; 70(6): 623-629, 2018 Dec 25.
Article in Chinese | MEDLINE | ID: mdl-30560271

ABSTRACT

Renal anemia, mainly caused by the deficiencies of erythropoietin (EPO) and iron metabolism disorder, is one of the most common complications of chronic kidney disease. Hypoxia-inducible factor (HIF) is a class of transcription factors responsible for maintaining homeostasis during oxygen deprivation. In normoxia, HIF is degraded by prolyl hydroxylase (PHD). While under hypoxic conditions, the hydroxylation activity of PHD is inhibited, and the cellular concentration of HIF is elevated, resulting in an increase in endogenous EPO production and iron absorption. Therefore, this regulating pathway, also termed as the HIF-PHD axis, has become a promising therapeutic target of treating renal anemia. Several innovative drugs acting as selective HIF-PHD inhibitors have been successfully developed in the past years, and some of them are undergoing clinical trials. In this review, we will introduce the definition and regulatory mechanism of HIF-PHD axis, as well as current insights into its physiologic and therapeutic role in renal anemia.


Subject(s)
Anemia/pathology , Hypoxia-Inducible Factor 1/metabolism , Kidney Diseases/pathology , Prolyl Hydroxylases/metabolism , Anemia/enzymology , Humans , Hypoxia/pathology , Kidney Diseases/enzymology , Oxygen
7.
J Vet Intern Med ; 31(6): 1700-1707, 2017 Nov.
Article in English | MEDLINE | ID: mdl-29031029

ABSTRACT

BACKGROUND: Oxidative stress plays a role in the pathophysiology of several diseases and has been documented as a contributor to disease in both the human and veterinary literature. One at-risk cell is the erythrocyte, however, the role of oxidative stress in anemia in dogs has not been widely investigated. HYPOTHESIS/OBJECTIVE: Anemic dogs will have an alteration in the activity of glutathione peroxidase (GPx), a decrease in of total antioxidant capacity (TAC), and an increased concentration of urinary 15-F2 -isoprostanes (F2 -IsoP) when compared to healthy dogs. ANIMALS: 40 client-owned dogs with anemia (PCV <30%) age-matched to 40 client-owned healthy control dogs. METHODS: Prospective, cross-sectional study. Whole blood GPx activity, plasma TAC, and urinary F2 -isoprostane concentrations were evaluated in each dog and compared between groups. RESULTS: Anemic dogs had significantly lower GPx activity (43.1 × 103 +/- 1.6 × 103 U/L) than did dogs in the control group (75.8 × 103 +/- 2.0 × 103 U/L; P < 0.0001). The GPx activity in dogs with hemolysis (103 +/- 0.8 × 103 U/L) was not significantly different (P = 0.57) than in dogs with nonhemolytic anemia (43.5 × 103 +/- 1.1 × 103 U/L). The TAC concentrations (P = 0.15) and urinary F2 -isoprostanes (P = 0.73) did not significantly differ between groups. CONCLUSIONS AND CLINICAL IMPORTANCE: Glutathione peroxidase activity was significantly decreased in anemic dogs indicating oxidative stress. Additional studies are warranted to determine if antioxidant supplementation would improve survival and overall outcome as part of a therapeutic regimen for anemic dogs.


Subject(s)
Anemia/veterinary , Dog Diseases/metabolism , F2-Isoprostanes/urine , Glutathione Peroxidase/blood , Oxidative Stress/physiology , Anemia/enzymology , Anemia/metabolism , Animals , Antioxidants/metabolism , Biomarkers/blood , Biomarkers/urine , Cross-Sectional Studies , Dog Diseases/enzymology , Dogs , Female , Male , Prospective Studies
8.
Afr Health Sci ; 17(1): 262-269, 2017 Mar.
Article in English | MEDLINE | ID: mdl-29026401

ABSTRACT

BACKGROUND: Blood-related hereditary diseases are widespread in Eastern and SouthWestern regions of Saudi Arabia until recently. In this study, we used Na+, K+ATPase as an enzymatic indicator for the diagnosis of the diseases. MATERIALS AND METHODS: Individuals with different blood diseases (iron deficiency (n=13), anemia (n=14), thalassemia (n=16) and sickle cell anemia (n=12) were studied for Na+, K+-ATPase activity in the plasma membrane of red blood cell and compared with those of the healthy ones (n=20) of the same age and gender living in Jeddah, Saudi Arabia. RESULTS: There was a significant elevation in the specific activity of Na+, K+ATPase in individuals with anemia compared with those of control (0.0094 + 0.001 nmol / mg protein/min versus 0.0061 ± 0.001). On the other hand, there was a significant reduction in enzyme activity in thalassemia (0.0028 ± 0.002 nmol / mg protein/min) and sickle cell anemia cases (0.0042 ±0.001 nmol / mg protein/min) compared to the control group. The cut off value for Na+, K+ATPase activity is 0.005 µmol Pi/min-showing 94% sensitivity and 93% specificity for the differentiation of blood abnormality. CONCLUSION: It can be recommended that the activity of Na+, K+-ATPase can be used for the diagnosis of individuals with blood diseases/disorders.


Subject(s)
Anemia/enzymology , Cell Membrane/enzymology , Erythrocyte Membrane/enzymology , Erythrocytes/enzymology , Sodium-Potassium-Exchanging ATPase/blood , Anemia, Iron-Deficiency , Anemia, Sickle Cell , Case-Control Studies , Female , Humans , Male , Saudi Arabia , Thalassemia
9.
Environ Sci Pollut Res Int ; 24(34): 26634-26645, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28956246

ABSTRACT

The present study was designed to investigate the hematotoxicity, sero-biochemical and histological changes due to the accumulation of BaCl2 and BaCO3, the most important barium salts in our daily lives, in different soft tissues including the liver, kidney, heart, and spleen of adult rats after an oral exposure for 30 consecutive days, and to explain the different mechanisms by which this metal can exert these impacts. For this purpose, adult male rats were divided into three main groups of 15 animals each: group I, serving as controls, group II, receiving BaCl2 orally in a dose of 179 mg barium/kg b.wt, and group III, receiving BaCO3 orally in a dose of 418 mg barium/kg b.wt. for 30 consecutive days. Obviously, normocytic normochromic anemia was evident in both barium groups. Serum biochemical analysis revealed significant declines in glutathione peroxidase, catalase, superoxide dismutase, and urea with significant elevations in malondialdehyde, lactate dehydrogenase, and creatine kinase levels. Hyperphosphatemia, hypokalemia, hypocalcemia, and hypochloremia were also evident in both barium groups. Besides, residual analysis of both barium salts in different body organs revealed significantly abundant barium residues in the liver, spleen, heart, and kidney, respectively in both barium salts groups. Moreover, splenic tissue showed hemosiderosis, peritubular congestion, and necrotic glomeruli with intratubular hemorrhage. Sever subepicardial congestion with intramuscular edema was evident in the heart. In conclusion, BaCl2 and BaCO3 were able to deliver mortalities, antioxidant enzymes exhaustion, and a sort of normocytic normochromic anemia, as well as marked disturbances in cardiac, hepatic, and renal functions due to the accumulation of these two salts in the soft tissues. Therefore, these results demonstrate the unrecognized toxicity of those two barium salts due to their accumulation in various soft tissues of the body and so, this needs to reconsider about barium exposure.


Subject(s)
Anemia/chemically induced , Barium Compounds/toxicity , Barium/toxicity , Carbonates/toxicity , Chlorides/toxicity , Kidney/metabolism , Liver/metabolism , Myocardium/metabolism , Anemia/blood , Anemia/enzymology , Animals , Antioxidants/metabolism , Barium/pharmacokinetics , Barium Compounds/pharmacokinetics , Carbonates/pharmacokinetics , Chlorides/pharmacokinetics , Kidney/drug effects , Kidney/pathology , Liver/drug effects , Liver/pathology , Male , Myocardium/pathology , Rats , Rats, Sprague-Dawley , Tissue Distribution
10.
J Med Chem ; 59(24): 11039-11049, 2016 12 22.
Article in English | MEDLINE | ID: mdl-28002958

ABSTRACT

The discovery of novel 4-hydroxy-2-(heterocyclic)pyrimidine-5-carboxamide inhibitors of hypoxia-inducible factor (HIF) prolyl hydroxylases (PHD) is described. These are potent, selective, orally bioavailable across several species, and active in stimulating erythropoiesis. Mouse and rat studies showed hematological changes with elevations of plasma EPO and circulating reticulocytes following single oral dose administration, while 4-week q.d. po administration in rat elevated hemoglobin levels. A major focus of the optimization process was to decrease the long half-life observed in higher species with early compounds. These efforts led to the identification of 28 (MK-8617), which has advanced to human clinical trials for anemia.


Subject(s)
Anemia/drug therapy , Drug Discovery , Enzyme Inhibitors/pharmacology , Hypoxia-Inducible Factor-Proline Dioxygenases/antagonists & inhibitors , Pyridazines/pharmacology , Pyrimidines/pharmacology , Administration, Oral , Anemia/enzymology , Animals , Dose-Response Relationship, Drug , Enzyme Inhibitors/administration & dosage , Enzyme Inhibitors/chemistry , Humans , Hypoxia-Inducible Factor-Proline Dioxygenases/metabolism , Mice , Mice, Inbred C57BL , Models, Molecular , Molecular Structure , Pyridazines/administration & dosage , Pyridazines/chemistry , Pyrimidines/administration & dosage , Pyrimidines/chemistry , Rats , Rats, Sprague-Dawley , Structure-Activity Relationship
11.
Tsitol Genet ; 49(2): 38-41, 2015.
Article in English | MEDLINE | ID: mdl-26030972

ABSTRACT

The aim of this study was to clarify the association between the inosine triphosphate pyrophosphatase (ITPA) gene variants and PEG-IFNalpha/RBV combination treatment induced anemia in chronic hepatitis C (CHC) Ukrainian patients. The data were collected from 80 CHC patients with HCV genotype 1 infection. All study participants received standard doses of PEG-IFNalpha and RBV According to the Hb level changes patients were distributed into: case group--42 patients with combination treatment induced anemia, and control group--38 patients with no signs of anemia. Genotyping for ITPA gene rs1127354 and rs7270101 variants was performed using PCR followed by RFLP assay. Fisher's exact test was used to estimate the difference in genotype and allelic distribution. Distribution of rs 7270101 genotypes was not significantly different between groups of CHC patients with RB Vinduced anemia and without it. The frequency of rs1127354 A allele carriers was significantly higher (P < < 0,05) in group of CHC patients without anemia (23.7%) comparing to the group ofpatients with anemia (7.3%). The respective allele frequency in control group (13.2%) was almost 3-fold higher (P < 0,05) comparing to the case group (4.9%). Significant association of ITPA gene rs1127354 with protection against RB V-induced hemolytic anemia was found in Ukrainian patients with CHC infection. Rs1127354 variant may assist as a pharmacogenetic marker in HCV antiviral therapy correction for side effect avoidance..


Subject(s)
Anemia/genetics , Antiviral Agents/adverse effects , Hepatitis C, Chronic/genetics , Polymorphism, Single Nucleotide , Pyrophosphatases/genetics , Ribavirin/adverse effects , Alleles , Anemia/chemically induced , Anemia/enzymology , Anemia/prevention & control , Antiviral Agents/administration & dosage , Case-Control Studies , Drug Therapy, Combination , Female , Gene Expression , Gene Frequency , Genotype , Hemoglobins/metabolism , Hepacivirus/genetics , Hepatitis C, Chronic/drug therapy , Hepatitis C, Chronic/enzymology , Hepatitis C, Chronic/virology , Host-Pathogen Interactions , Humans , Interferon alpha-2 , Interferon-alpha/administration & dosage , Male , Molecular Typing , Polyethylene Glycols/administration & dosage , Pyrophosphatases/metabolism , Recombinant Proteins/administration & dosage , Ribavirin/administration & dosage , Ukraine
12.
Clin Chem Lab Med ; 53(12): 2021-9, 2015 Nov.
Article in English | MEDLINE | ID: mdl-25968438

ABSTRACT

BACKGROUND: ITPA polymorphisms have been associated with protection against ribavirin-induced anemia in chronic hepatitis C (HCV) patients. Here we determined the association of inosine triphosphate pyrophosphohydrolase (inosine triphosphatase or ITPase) enzyme activity with ITPA genotype in predicting ribavirin-induced anemia. METHODS: In a cohort of 106 HCV patients, hemoglobin (Hb) values were evaluated after 4 weeks (T4) and at the time of lowest Hb value (Tnadir). ITPase activity was measured and ITPA genotype determined. Single-nucleotide polymorphisms (SNPs) tested were c.124+21A>C and c.94C>A. ITPase activity ≥1.11 mU/mol Hb was considered as normal. RESULTS: After 4 weeks of treatment, 78% of the patients with normal ITPase activity were anemic and 21% of the patients with low ITPase activity (p<0.001). Stratified by genotype, the percentages of anemic patients were: wt/wt 76%, wt/c.124+21A>C 46% (p=0.068), and wt/c.94C>A 29% (p=0.021). At Tnadir, virtually all patients with normal ITPase activity were anemic, compared to only 64% of the patients with low activity (p=0.02). Thirteen patients had wt/c.124+241A>C genotype. Within this group all five patients with normal ITPase activity and only four of eight with decreased activity developed anemia. Presence of HCV RNA did not influence ITPase activity. CONCLUSIONS: This study is the first to report that ITPase activity predicts the development of anemia during ribavirin treatment. ITPase activity and ITPA genotype have high positive predictive values for development of ribavirin-induced anemia at any time during treatment, but ITPase activity predicts ribavirin-induced anemia more accurately.


Subject(s)
Anemia/chemically induced , Anemia/complications , Hepatitis C/complications , Hepatitis C/drug therapy , Pyrophosphatases/genetics , Pyrophosphatases/metabolism , Ribavirin/adverse effects , Adult , Aged , Aged, 80 and over , Anemia/enzymology , Anemia/genetics , Cohort Studies , DNA/blood , DNA/genetics , Female , Genotype , Hepatitis C/enzymology , Hepatitis C/genetics , Humans , Male , Middle Aged , Polymorphism, Single Nucleotide/genetics , Ribavirin/therapeutic use , Young Adult , Inosine Triphosphatase
13.
PLoS Negl Trop Dis ; 9(3): e0003602, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25746733

ABSTRACT

Safe treatment of Plasmodium vivax requires diagnosis of both the infection and status of erythrocytic glucose-6-phosphate dehydrogenase (G6PD) activity because hypnozoitocidal therapy against relapse requires primaquine, which causes a mild to severe acute hemolytic anemia in G6PD deficient patients. Many national malaria control programs recommend primaquine therapy without G6PD screening but with monitoring due to a broad lack of G6PD deficiency screening capacity. The degree of risk in doing so hinges upon the level of residual G6PD activity among the variants present in any given area. We conducted studies on Sumba Island in eastern Indonesia in order to assess the potential threat posed by primaquine therapy without G6PD screening. We sampled 2,033 residents of three separate districts in western Sumba for quantitative G6PD activity and 104 (5.1%) were phenotypically deficient (<4.6U/gHb; median normal 10U/gHb). The villages were in two distinct ecosystems, coastal and inland. A positive correlation occurred between the prevalence of malaria and G6PD deficiency: 5.9% coastal versus inland 0.2% for malaria (P<0.001), and 6.7% and 3.1% for G6PD deficiency (P<0.001) at coastal and inland sites, respectively. The dominant genotypes of G6PD deficiency were Vanua Lava, Viangchan, and Chatham, accounting for 98.5% of the 70 samples genotyped. Subjects expressing the dominant genotypes all had less than 10% of normal enzyme activities and were thus considered severe variants. Blind administration of anti-relapse primaquine therapy at Sumba would likely impose risk of serious harm.


Subject(s)
Antimalarials/therapeutic use , Glucosephosphate Dehydrogenase Deficiency/epidemiology , Malaria, Vivax/drug therapy , Primaquine/therapeutic use , Adolescent , Adult , Aged , Aged, 80 and over , Anemia/enzymology , Child , Child, Preschool , Female , Humans , Indonesia/epidemiology , Malaria, Vivax/enzymology , Male , Middle Aged , Prevalence , Recurrence
14.
J Vet Med Sci ; 77(6): 743-6, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25716288

ABSTRACT

Erythrocyte pyruvate kinase (PK) deficiency is an inherited glycolytic erythroenzymopathy caused by mutations of the PKLR gene. A causative mutation of the feline PKLR gene was originally identified in Abyssinian and Somali cats in the U.S.A. In the present study, a TaqMan probe-based real-time PCR genotyping assay was developed and evaluated for rapid genotyping and large-scale screening for this mutation. Furthermore, a genotyping survey was carried out in a population of four popular purebred cats in Japan to determine the current mutant allele frequency. The assay clearly displayed all genotypes of feline PK deficiency, indicating its suitability for large-scale survey as well as diagnosis. The survey demonstrated that the mutant allele frequency in Abyssinian and Somali cats was high enough to warrant measures to control and prevent the disease. The mutant allele frequency was relatively low in Bengal and American Shorthair cats; however, the testing should still be carried out to prevent the spread of the disease. In addition, PK deficiency should always be considered in the differential diagnosis of anemia in purebred cats in Japan as well as worldwide.


Subject(s)
Anemia, Hemolytic, Congenital Nonspherocytic/veterinary , Cat Diseases/enzymology , Cat Diseases/genetics , Genotyping Techniques/veterinary , Pyruvate Kinase/deficiency , Pyruvate Kinase/genetics , Pyruvate Metabolism, Inborn Errors/veterinary , Anemia/diagnosis , Anemia/enzymology , Anemia/veterinary , Anemia, Hemolytic, Congenital Nonspherocytic/genetics , Animals , Cats , Diagnosis, Differential , Gene Frequency/genetics , Japan , Mutation/genetics , Pyruvate Metabolism, Inborn Errors/genetics , Real-Time Polymerase Chain Reaction/veterinary , Species Specificity
16.
Am J Physiol Regul Integr Comp Physiol ; 307(1): R13-25, 2014 Jul 01.
Article in English | MEDLINE | ID: mdl-24760996

ABSTRACT

Tissue hypoxia likely contributes to anemia-induced organ injury and mortality. Severe anemia activates hypoxia-inducible factor (HIF) signaling by hypoxic- and neuronal nitric oxide (NO) synthase- (nNOS) dependent mechanisms. However, organ-specific hemoglobin (Hb) thresholds for increased HIF expression have not been defined. To assess organ-specific Hb thresholds for tissue hypoxia, HIF-α (oxygen-dependent degradation domain, ODD) luciferase mice were hemodiluted to mild, moderate, or severe anemia corresponding to Hb levels of 90, 70, and 50 g/l, respectively. HIF luciferase reporter activity, HIF protein, and HIF-dependent RNA levels were assessed. In the brain, HIF-1α was paradoxically decreased at mild anemia, returned to baseline at moderate anemia, and then increased at severe anemia. Brain HIF-2α remained unchanged at all Hb levels. Both kidney HIF-1α and HIF-2α increased earlier (Hb ∼70-90 g/l) in response to anemia. Liver also exhibited an early HIF-α response. Carotid blood flow was increased early (Hb ∼70, g/l), but renal blood flow remained relatively constant, only increased at Hb of 50 g/l. Anemia increased nNOS (brain and kidney) and endothelia NOS (eNOS) (kidney) levels. Whereas anemia-induced increases in brain HIFα were nNOS-dependent, our current data demonstrate that increased renal HIFα was nNOS independent. HIF-dependent RNA levels increased linearly (∼10-fold) in the brain. However, renal HIF-RNA responses (MCT4, EPO) increased exponentially (∼100-fold). Plasma EPO levels increased near Hb threshold of 90 g/l, suggesting that the EPO response is sensitive. Collectively, these observations suggest that each organ expresses a different threshold for cellular HIF/NOS hypoxia responses. This knowledge may help define the mechanism(s) by which the brain and kidney maintain oxygen homeostasis during anemia.


Subject(s)
Anemia/enzymology , Basic Helix-Loop-Helix Transcription Factors/metabolism , Hemoglobins/metabolism , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Hypoxia/enzymology , Nitric Oxide Synthase Type III/metabolism , Nitric Oxide Synthase Type I/metabolism , Acute Disease , Anemia/blood , Anemia/etiology , Anemia/genetics , Anemia/physiopathology , Animals , Biomarkers/blood , Brain/blood supply , Brain/enzymology , Cerebrovascular Circulation , Disease Models, Animal , Erythropoietin/metabolism , Hemodilution , Hemodynamics , Humans , Hypoxia/blood , Hypoxia/etiology , Hypoxia/genetics , Hypoxia/physiopathology , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , Kidney/blood supply , Kidney/enzymology , Liver/blood supply , Liver/enzymology , Luciferases, Firefly/genetics , Luciferases, Firefly/metabolism , Mice , Mice, Transgenic , Monocarboxylic Acid Transporters/metabolism , Muscle Proteins/metabolism , Recombinant Fusion Proteins/metabolism , Renal Circulation , Severity of Illness Index
17.
Blood ; 122(25): 4047-53, 2013 Dec 12.
Article in English | MEDLINE | ID: mdl-24174625

ABSTRACT

Ruxolitinib is a potent Janus kinase (JAK)1/JAK2 inhibitor that has demonstrated rapid reductions in splenomegaly and marked improvement in disease-related symptoms and quality of life in patients with myelofibrosis (MF). The present analysis reports the 3-year follow-up (median, 151 weeks) of the efficacy and safety of Controlled Myelofibrosis Study With Oral Janus-associated Kinase (JAK) Inhibitor Treatment-II (the COMFORT-II Trial), comparing ruxolitinib with the best available therapy (BAT) in 219 patients with intermediate-2 and high-risk MF. In the ruxolitinib arm, with continued therapy, spleen volume reductions of ≥35% by magnetic resonance imaging (equivalent to approximately 50% reduction by palpation) were sustained for at least 144 weeks, with the probability of 50% (95% confidence interval [CI], 36-63) among patients achieving such degree of response. At the time of this analysis, 45% of the patients randomized to ruxolitinib remained on treatment. Ruxolitinib continues to be well tolerated. Anemia and thrombocytopenia were the main toxicities, but they were generally manageable, improved over time, and rarely led to treatment discontinuation (1% and 3.6% of patients, respectively). No single nonhematologic adverse event led to definitive ruxolitinib discontinuation in more than 1 patient. Additionally, patients randomized to ruxolitinib showed longer overall survival than those randomized to BAT (hazard ratio, 0.48; 95% CI, 0.28-0.85; log-rank test, P = .009).


Subject(s)
Primary Myelofibrosis/drug therapy , Primary Myelofibrosis/mortality , Protein Kinase Inhibitors/administration & dosage , Pyrazoles/administration & dosage , Anemia/chemically induced , Anemia/drug therapy , Anemia/enzymology , Anemia/mortality , Disease-Free Survival , Female , Follow-Up Studies , Humans , Janus Kinase 1/antagonists & inhibitors , Janus Kinase 2/antagonists & inhibitors , Male , Nitriles , Primary Myelofibrosis/enzymology , Protein Kinase Inhibitors/adverse effects , Pyrazoles/adverse effects , Pyrimidines , Survival Rate , Thrombocytopenia/chemically induced , Thrombocytopenia/drug therapy , Thrombocytopenia/enzymology , Thrombocytopenia/mortality , Time Factors
18.
Res Vet Sci ; 95(3): 1026-30, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23928180

ABSTRACT

The aim of this study was to evaluate the ecto-adenosine deaminase (E-ADA) activity in erythrocytes of lambs experimentally infected with Haemonchus contortus, correlating it with the degrees of anemia of the experimental animals. A total of 14 healthy lambs, with negative fecal exam for parasites, were to carry out the present study. They were divided into two groups, composed by seven animals: Group A represented the healthy animals (uninfected), while in Group B the animals were infected with 15,000 larvae of H. contortus. Blood was drawn on the days 15, 45 and 75 post-infection (PI) in order to perform the hematological analysis, as well as the mensuration of E-ADA activity in erythrocytes. Parasitological stool exam were performed on the same days mentioned above to follow up the evolution of the infection, as well to determine the number of eggs per gram of feces (EPG). On day 15PI, the animals presented negative EPG and there was not significant (P>0.05) difference between groups in relation to E-ADA activity and hematologic parameters. Animals in Group B had positive EPG for helminths on days 45 and 75 PI, accompanied by varying degrees of anemia, when compared to Group A. At the same periods E-ADA activity was significantly (P<0.05) increased in the erythrocytes of animals of Group B when compared with the not-infected ones. Statistically, there was a negative correlation (P<0.01) between activity E-ADA in erythrocytes and hematocrit on days 45 (r = -0.76) and 75 (r = -0.85)PI. Based on these results and in the scientific literature, it is possible to conclude that the E-ADA may participate on mechanisms related with the pathogenesis and host response against anemia caused by H. contortus.


Subject(s)
Adenosine Deaminase/blood , Anemia/veterinary , Erythrocytes/enzymology , Haemonchiasis/veterinary , Haemonchus , Sheep Diseases/parasitology , Adenosine Deaminase/physiology , Anemia/enzymology , Anemia/parasitology , Animals , Feces/parasitology , Haemonchiasis/enzymology , Hematocrit/veterinary , Hemoglobins/analysis , Male , Parasite Egg Count/veterinary , Sheep/parasitology , Sheep Diseases/enzymology
19.
J Hepatol ; 59(4): 667-74, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23707372

ABSTRACT

BACKGROUND & AIMS: Anemia is a common adverse effect of telaprevir (TVR) in combination with pegylated interferon (PegIFN)α and ribavirin (RBV) therapy. It occurs at a higher incidence with the TVR relative to PegIFNα and RBV alone. We herein evaluate the baseline and on-treatment predictors of the development of severe anemia by chronic hepatitis C virus (HCV) patients receiving TVR-based triple therapy. METHODS: This prospective, multicenter study consisted of 292 patients (median age: 62 years) infected with HCV genotype 1. All received 12 weeks of TVR in combination with 24 weeks of PegIFNα2b and RBV. The definition of severe anemia during antiviral treatment is hemoglobin (Hb)<85 g/L. RESULTS: 101 (34.6%) patients developed severe anemia during the treatment period. Multivariable logistic regression analysis of possible pretreatment predictors of the development of severe anemia extracted baseline Hb < 135 g/L (Hazard ratio [HR], 2.53; p = 0.0013), estimated glomerular filtration rate <80 ml/min/1.73 m(2) (HR, 1.83; p = 0.0265), and inosine triphosphatase (ITPA) CC genotype (rs1127354) (HR, 2.91; p = 0.0024). For patients with ITPA CC (n = 227), multivariable logistic regression analysis of possible pretreatment and on-treatment predictors of the development of severe anemia extracted Hb level at week 2 (HR, 0.96; p = 0.0085) and the initial four weeks of weight-adjusted TVR (HR, 1.05; p = 0.0281). CONCLUSIONS: Anemia remains a risk for all patients treated with TVR-based triple therapy. However, ITPA polymorphism (rs1127354) is useful for predicting the development of severe anemia and will be helpful in the management of treatment.


Subject(s)
Anemia/etiology , Antiviral Agents/adverse effects , Hepatitis C, Chronic/drug therapy , Oligopeptides/adverse effects , Aged , Anemia/enzymology , Anemia/genetics , Antiviral Agents/administration & dosage , Drug Therapy, Combination , Female , Genotype , Hemoglobins/metabolism , Hepacivirus/genetics , Hepatitis C, Chronic/blood , Hepatitis C, Chronic/virology , Humans , Interferon alpha-2 , Interferon-alpha/administration & dosage , Male , Middle Aged , Oligopeptides/administration & dosage , Polyethylene Glycols/administration & dosage , Polymorphism, Single Nucleotide , Prospective Studies , Pyrophosphatases/genetics , Recombinant Proteins/administration & dosage , Ribavirin/administration & dosage , Risk Factors
20.
World J Gastroenterol ; 19(9): 1387-95, 2013 Mar 07.
Article in English | MEDLINE | ID: mdl-23538996

ABSTRACT

AIM: To investigate and clarify, for the first time, the role of inosine triphosphate pyrophosphatase (ITPA) polymorphism in Egyptian chronic hepatitis C virus (HCV) patients. METHODS: The human genomic DNA of all patients was extracted from peripheral blood cells in order to determine the single nucleotide polymorphism (SNP) of ITPA (rs1127354). SNP genotyping was performed by real time polymerase chain reaction (PCR, ABI TaqMan allelic discrimination kit) for 102 treatment-naive Egyptian patients with chronic HCV. All patients had no evidence of cardiovascular or renal diseases. They received a combination treatment of pegylated interferon α (PEG-IFNα) as a weekly subcutaneous dose plus an oral weight-adjusted dose of ribavirin (RBV). The majority received PEG-IFNα2a (70.6%) while 29.4% received PEG-IFNα2b. The planned duration of treatment was 24-48 wk according to the viral kinetics throughout the course of treatment. Pre-treatment liver biopsy was done for each patient for evaluation of fibrosis stage and liver disease activity. The basal viral load level was detected quantitatively by real time PCR while viral load throughout the treatment course was performed qualitatively by COBAS TaqMan assay. RESULTS: Ninety-three patients (91.2%) had ITPA SNP CC genotype and 9 (8.8%) had non-CC genotype (CA and AA). The percentage of hemoglobin (Hb) decline was higher for CC patients than for non-CC patients, particularly at weeks 4 and 8 (P = 0.047 and 0.034, respectively). During the first 12 wk of treatment, CC patients had significantly more Hb decline > 3 g/dL than non-CC patients: 64.5% vs 22.2% at weeks 8 and 12, respectively, (P = 0.024 and 0.038). Reduction of the amount of the planned RBV dose was significantly higher for CC patients than non-CC patients during the first 12 wk (18% ± 12.1% vs 8.5% ± 10.2%, P = 0.021). The percentage of CC patients with RBV dose reduction was significantly greater than that of non-CC patients (77.4% vs 44.4%, P = 0.044). Multivariate analysis identified only the percentage of RBV dose as a predictor for Hb decline. Platelet decline was significantly higher in non-CC patients than CC patients at weeks 12, 24 and 48 (P = 0.018, 0.009 and 0.026, respectively). CONCLUSION: Rs1127354 ITPA polymorphism plays a decisive role in protecting against treatment-induced anemia and the need for RBV dose reduction in Egyptian HCV patients.


Subject(s)
Anemia/prevention & control , Antiviral Agents/adverse effects , Hepatitis C, Chronic/drug therapy , Interferon-alpha/adverse effects , Polyethylene Glycols/adverse effects , Polymorphism, Single Nucleotide , Pyrophosphatases/genetics , Ribavirin/adverse effects , Adult , Anemia/blood , Anemia/chemically induced , Anemia/enzymology , Anemia/genetics , Biomarkers/blood , Drug Therapy, Combination , Egypt/epidemiology , Female , Gene Frequency , Genetic Predisposition to Disease , Hemoglobins/metabolism , Hepatitis C, Chronic/diagnosis , Hepatitis C, Chronic/enzymology , Hepatitis C, Chronic/epidemiology , Hepatitis C, Chronic/genetics , Humans , Interferon alpha-2 , Logistic Models , Male , Multivariate Analysis , Odds Ratio , Phenotype , Recombinant Proteins/adverse effects , Risk Factors , Time Factors , Treatment Outcome
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