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Mitochondrial dysfunction is associated with a spectrum of human conditions, ranging from rare, inborn errors of metabolism to the aging process. To identify pathways that modify mitochondrial dysfunction, we performed genome-wide CRISPR screens in the presence of small-molecule mitochondrial inhibitors. We report a compendium of chemical-genetic interactions involving 191 distinct genetic modifiers, including 38 that are synthetic sick/lethal and 63 that are suppressors. Genes involved in glycolysis (PFKP), pentose phosphate pathway (G6PD), and defense against lipid peroxidation (GPX4) scored high as synthetic sick/lethal. A surprisingly large fraction of suppressors are pathway intrinsic and encode mitochondrial proteins. A striking example of such "intra-organelle" buffering is the alleviation of a chemical defect in complex V by simultaneous inhibition of complex I, which benefits cells by rebalancing redox cofactors, increasing reductive carboxylation, and promoting glycolysis. Perhaps paradoxically, certain forms of mitochondrial dysfunction may best be buffered with "second site" inhibitors to the organelle.
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Genes Modificadores , Mitocondrias/genética , Mitocondrias/patología , Autoantígenos/metabolismo , Muerte Celular/efectos de los fármacos , Citosol/efectos de los fármacos , Citosol/metabolismo , Complejo I de Transporte de Electrón/metabolismo , Epistasis Genética/efectos de los fármacos , Ferroptosis/efectos de los fármacos , Ferroptosis/genética , Genoma , Glutatión Peroxidasa/metabolismo , Glucólisis/efectos de los fármacos , Glucólisis/genética , Humanos , Células K562 , Mitocondrias/efectos de los fármacos , Oligomicinas/toxicidad , Oxidación-Reducción , Fosforilación Oxidativa/efectos de los fármacos , Vía de Pentosa Fosfato/efectos de los fármacos , Vía de Pentosa Fosfato/genética , Especies Reactivas de Oxígeno/metabolismo , Ribonucleoproteínas/metabolismo , Antígeno SS-BRESUMEN
B cell activation during normal immune responses and oncogenic transformation impose increased metabolic demands on B cells and their ability to retain redox homeostasis. While the serine/threonine-protein phosphatase 2A (PP2A) was identified as a tumor suppressor in multiple types of cancer, our genetic studies revealed an essential role of PP2A in B cell tumors. Thereby, PP2A redirects glucose carbon utilization from glycolysis to the pentose phosphate pathway (PPP) to salvage oxidative stress. This unique vulnerability reflects constitutively low PPP activity in B cells and transcriptional repression of G6PD and other key PPP enzymes by the B cell transcription factors PAX5 and IKZF1. Reflecting B-cell-specific transcriptional PPP-repression, glucose carbon utilization in B cells is heavily skewed in favor of glycolysis resulting in lack of PPP-dependent antioxidant protection. These findings reveal a gatekeeper function of the PPP in a broad range of B cell malignancies that can be efficiently targeted by small molecule inhibition of PP2A and G6PD.
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Carbono/metabolismo , Glucosa/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Animales , Linfocitos B/citología , Linfocitos B/metabolismo , Línea Celular Tumoral , Supervivencia Celular , Glucosafosfato Deshidrogenasa/genética , Glucosafosfato Deshidrogenasa/metabolismo , Glucólisis , Humanos , Factor de Transcripción Ikaros/genética , Factor de Transcripción Ikaros/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Estrés Oxidativo , Factor de Transcripción PAX5/genética , Factor de Transcripción PAX5/metabolismo , Vía de Pentosa Fosfato , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Proteína Fosfatasa 2/deficiencia , Proteína Fosfatasa 2/genética , Proteína Fosfatasa 2/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Transcripción GenéticaRESUMEN
I was attracted to hematology because by combining clinical findings with the use of a microscope and simple laboratory tests, one could often make a diagnosis. I was attracted to genetics when I learned about inherited blood disorders, at a time when we had only hints that somatic mutations were also important. It seemed clear that if we understood not only what genetic changes caused what diseases but also the mechanisms through which those genetic changes contribute to cause disease, we could improve management. Thus, I investigated many aspects of the glucose-6-phosphate dehydrogenase system, including cloning of the gene, and in the study of paroxysmal nocturnal hemoglobinuria (PNH), I found that it is a clonal disorder; subsequently, we were able to explain how a nonmalignant clone can expand, and I was involved in the first trial of PNH treatment by complement inhibition. I was fortunate to do clinical and research hematology in five countries; in all of them, I learned from mentors, from colleagues, and from patients.
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Hemoglobinuria Paroxística , Humanos , Hemoglobinuria Paroxística/genética , Hemoglobinuria Paroxística/patología , Células Sanguíneas/patología , Células Clonales/patologíaRESUMEN
Human glucose-6-phosphate dehydrogenase (G6PD) is the main cellular source of NADPH, and thus plays a key role in maintaining reduced glutathione to protect cells from oxidative stress disorders such as hemolytic anemia. G6PD is a multimeric enzyme that uses the cofactors ß-D-glucose 6-phosphate (G6P) and "catalytic" NADP+ (NADP+c), as well as a "structural" NADP+ (NADP+s) located â¼25 Å from the active site, to generate NADPH. While X-ray crystallographic and biochemical studies have revealed a role for NADP+s in maintaining the catalytic activity by stabilizing the multimeric G6PD conformation, other potential roles for NADP+s have not been evaluated. Here, we determined the high resolution cryo-electron microscopy structures of human wild-type G6PD in the absence of bound ligands and a catalytic G6PD-D200N mutant bound to NADP+c and NADP+s in the absence or presence of G6P. A comparison of these structures, together with previously reported structures, reveals that the unliganded human G6PD forms a mixture of dimers and tetramers with similar overall folds, and binding of NADP+s induces a structural ordering of a C-terminal extension region and allosterically regulates G6P binding and catalysis. These studies have implications for understanding G6PD deficiencies and for therapy of G6PD-mediated disorders.
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Glucosafosfato Deshidrogenasa , NADP , Dominio Catalítico/genética , Microscopía por Crioelectrón , Glucosafosfato Deshidrogenasa/química , Glucosafosfato Deshidrogenasa/genética , Deficiencia de Glucosafosfato Deshidrogenasa/tratamiento farmacológico , Deficiencia de Glucosafosfato Deshidrogenasa/enzimología , Humanos , Mutación , NADP/química , Multimerización de ProteínaRESUMEN
BACKGROUND: Recently, there has been an unexplained increase in the incidence of blackwater fever (BWF) in Eastern Uganda. In this study, we evaluate the association between immune complexes, glucose-6-phosphate dehydrogenase (G6PD) deficiency, and the occurrence and recurrence of BWF in children with severe malaria (SM). METHODS: Between 2014 and 2017, children aged six months to <4 years hospitalized with SM and community children (CC) were recruited at two hospitals in Central and Eastern Uganda. We measured serum circulating immune complexes (cIC) and their relationship to SM complications and post-discharge outcomes and evaluated effect mediation through G6PD deficiency. RESULTS: 557 children with SM and 101 CC were enrolled. The mean age of children was 2.1 years. Children with SM had higher cIC levels than CC, p<0.001. After controlling for age, sex, and site, cIC were associated with severe anemia, jaundice, and BWF (adjusted odds ratio, 95% confidence interval: 7.33 (3.45, 15.58), p<0.0001; 4.31 (1.68, 11.08), p=0.002; and 5.21 (2.06, 13.18), p<0.0001), respectively. cIC predicted readmissions for SM, severe anemia, and BWF (adjusted incidence rate ratios (95% confidence interval): 2.11 (1.33, 3.34), p=0.001; 8.62 (2.80, 26.59), p<0.0001; and 7.66 (2.62, 22.45), p<0.0001), respectively. The relationship was most evident in males where the frequency of the G6PD African allele (A-) was 16.8%. G6PD deficiency was associated with increases in cIC in males (p=0.01) and mediation analysis suggested G6PD deficiency contributes to recurrent severe anemia and BWF via increased cIC. CONCLUSIONS: Immune complexes are associated with hemolytic complications and predict recurrences in SM survivors.
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Studies have shown that decreased expression of glucose-6-phosphate dehydrogenase (G6PD) play an important role in DKD. However, the upstream and downstream pathways of G6PD downregulation leading to DKD have not been elucidated.We conducted a series of studies including clinical study, animal studies, and in vitro studies to explore this. Firstly, a total of 90 subjects were evaluated. The urinary G6PD activity and its association with the clinical markers were analyzed. Then, urine differentially microRNAs that can bind and degrade G6PD were screened and verified in DKD patients. After that, high glucose (HG)-cultured Human kidney cells (HK-2) and Zucker diabetic fatty (ZDF) rats were used to test the roles of miR-7977/G6PD/albumin-induced autophagy in DKD. The plasma and urinary G6PD activity were decreased significantly in patients with DKD, accompanied by increased urinary mir-7977 level. The fasting plasma glucose (FPG), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and urinary albumin excretion were independent predictors of urinary G6PD activity by multiple linear regression analysis.The increased expression of miR-7977 and decreased expression of G6PD were also found in the kidney of ZDF rats with early renal tubular damage.In HK-2 cells cultured with normal situation, low level of albumin could induce autophagy along with the stimulation of G6PD although this was impaired under high glucose. Overexpression of G6PD reversed albumin-induced autophagy in HK2 cells under high glucose.Inhibition mir-7977 expression led to significantly increased expression of G6PD and reversed the effects of high glucose on albumin induced autophagy.Our study supports a new mechanism of G6PD downregulation in DKD.
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Primaquine is the mainstream antimalarial drug to prevent Plasmodium vivax relapses. However, this drug can induce hemolysis in patients with glucose-6-phosphate dehydrogenase deficiency. Nanostructure formulations of primaquine loaded with D-galactose were used as a strategy to target the drug to the liver and decrease the hemolytic risks. Nanoemulsion (NE-Pq) and nanochitosan (NQ-Pq) formulations of primaquine diphosphate containing D-galactose were prepared and characterized by their physicochemistry properties. Pharmacokinetic and biodistribution studies were conducted using Swiss Webster mice. A single dose of 10 mg/kg of each nanoformulation or free primaquine solution was administered by gavage to the animals, which were killed at 0.5, 1, 2, 4, 8, and 24 hours. Blood samples and tissues were collected, processed, and analyzed by high-performance liquid chromatography. The nanoformulation showed sizes around 200 nm (NE-Pq) and 400 nm (NQ-Pq) and physicochemical stability for over 30 days. Free primaquine solution achieved higher primaquine Cmax in the liver than NE-Pq or NQ-Pq at 0.5 hours. However, the half-life and mean residence time (MRT) of primaquine in the liver were three times higher with the NQ-Pq formulation than with free primaquine, and the volume distribution was four times higher. Conversely, primaquine's half-life, MRT, and volume distribution in the plasma were lower for NQ-Pq than for free primaquine. NE-Pq, on the other hand, accumulated more in the lungs but not in the liver. Galactose-coated primaquine nanochitosan formulation showed increased drug targeting to the liver compared to free primaquine and may represent a promising strategy for a more efficient and safer radical cure for vivax malaria.
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Antimaláricos , Quitosano , Galactosa , Hígado , Primaquina , Primaquina/farmacocinética , Primaquina/química , Animales , Ratones , Hígado/metabolismo , Hígado/efectos de los fármacos , Galactosa/química , Quitosano/química , Antimaláricos/farmacocinética , Nanopartículas/química , Distribución Tisular , Nanoestructuras/química , MasculinoRESUMEN
BACKGROUND: Glycolysis is critical for harvesting abundant energy to maintain the tumor microenvironment in malignant tumors. Retinoic acid-related orphan receptor α (RORα) has been identified as a circadian gene. However, the association of glycolysis with RORα in regulating gastric cancer (GC) proliferation remains poorly understood. METHODS: Bioinformatic analysis and retrospective study were utilized to explore the role of RORα in cell cycle and glycolysis in GC. The mechanisms were performed in vitro and in vivo including colony formation, Cell Counting Kit-8 (CCK-8), Epithelial- mesenchymal transition (EMT) and subcutaneous tumors of mice model assays. The key drives between RORα and glycolysis were verified through western blot and chip assays. Moreover, we constructed models of high proliferation and high glucose environments to verify a negative feedback and chemoresistance through a series of functional experiments in vitro and in vivo. RESULTS: RORα was found to be involved in the cell cycle and glycolysis through a gene set enrichment analysis (GSEA) algorithm. GC patients with low RORα expression were not only associated with high circulating tumor cells (CTC) and high vascular endothelial growth factor (VEGF) levels. However, it also presented a positive correlation with the standard uptake value (SUV) level. Moreover, the SUVmax levels showed a positive linear relation with CTC and VEGF levels. In addition, RORα expression levels were associated with glucose 6 phosphate dehydrogenase (G6PD) and phosphofructokinase-2/fructose-2,6-bisphosphatase (PFKFB3) expression levels, and GC patients with low RORα and high G6PD or low RORα and high PFKFB3 expression patterns had poorest disease-free survival (DFS). Functionally, RORα deletion promoted GC proliferation and drove glycolysis in vitro and in vivo. These phenomena were reversed by the RORα activator SR1078. Moreover, RORα deletion promoted GC proliferation through attenuating G6PD and PFKFB3 induced glycolytic activity in vitro and in vivo. Mechanistically, RORα was recruited to the G6PD and PFKFB3 promoters to modulate their transcription. Next, high proliferation and high glucose inhibited RORα expression, which indicated that negative feedback exists in GC. Moreover, RORα deletion improved fluorouracil chemoresistance through inhibition of glucose uptake. CONCLUSION: RORα might be a novel biomarker and therapeutic target for GC through attenuating glycolysis.
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BACKGROUND: Liver Hepatocellular carcinoma (LIHC) exhibits a high incidence of liver cancer with escalating mortality rates over time. Despite this, the underlying pathogenic mechanism of LIHC remains poorly understood. MATERIALS & METHODS: To address this gap, we conducted a comprehensive investigation into the role of G6PD in LIHC using a combination of bioinformatics analysis with database data and rigorous cell experiments. LIHC samples were obtained from TCGA, ICGC and GEO databases, and the differences in G6PD expression in different tissues were investigated by differential expression analysis, followed by the establishment of Nomogram to determine the percentage of G6PD in causing LIHC by examining the relationship between G6PD and clinical features, and the subsequent validation of the effect of G6PD on the activity, migration, and invasive ability of hepatocellular carcinoma cells by using the low expression of LI-7 and SNU-449. Additionally, we employed machine learning to validate and compare the predictive capacity of four algorithms for LIHC patient prognosis. RESULTS: Our findings revealed significantly elevated G6PD expression levels in liver cancer tissues as compared to normal tissues. Meanwhile, Nomogram and Adaboost, Catboost, and Gbdt Regression analyses showed that G6PD accounted for 46%, 31%, and 49% of the multiple factors leading to LIHC. Furthermore, we observed that G6PD knockdown in hepatocellular carcinoma cells led to reduced proliferation, migration, and invasion abilities. Remarkably, the Decision Tree C5.0 decision tree algorithm demonstrated superior discriminatory performance among the machine learning methods assessed. CONCLUSION: The potential diagnostic utility of G6PD and Decision Tree C5.0 for LIHC opens up a novel avenue for early detection and improved treatment strategies for hepatocellular carcinoma.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Pronóstico , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Algoritmos , Aprendizaje AutomáticoRESUMEN
BACKGROUND: G6PD deficiency is a common inherited disorder worldwide and has a higher incidence rate in southern China. Many variants of G6PD result from point mutations in the G6PD gene, leading to decreased enzyme activity. This study aimed to analyse the genotypic and phenotypic characteristics of G6PD deficiency in Guangzhou, China. METHODS: In this study, a total of 20,208 unrelated participants were screened from 2020 to 2022. G6PD deficiency was further analysed by quantitative enzymatic assay and G6PD mutation analysis. The unidentified genotype of the participants was further ascertained by direct DNA sequencing. RESULTS: A total of 12 G6PD mutations were identified. Canton (c.1376G>T) and Kaiping (c.1388G>A) were the most common variants, and different mutations led to varying levels of G6PD enzyme activity. Comparing the enzyme activities of the 6 missense mutations between the sexes, we found significant differences (P < 0.05) in the enzyme activities of both male hemizygotes and female heterozygotes. Two previously unreported mutations (c.1438A>T and c.946G>A) were identified. CONCLUSIONS: This study provided detailed genotypes of G6PD deficiency in Guangzhou, which could be valuable for diagnosing and researching G6PD deficiency in this area.
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Deficiencia de Glucosafosfato Deshidrogenasa , Femenino , Humanos , Masculino , China/epidemiología , Genotipo , Glucosafosfato Deshidrogenasa/genética , Deficiencia de Glucosafosfato Deshidrogenasa/epidemiología , Deficiencia de Glucosafosfato Deshidrogenasa/genética , Heterocigoto , MutaciónRESUMEN
OBJECTIVES: This study aimed to investigate the incidence rate and spectrum of gene mutations of Glucose-6-phosphate dehydrogenase (G6PD) deficiency in the Huizhou city of southern China to provide a scientific basis for disease prevention and control in the area. METHODS: From March 2003 to December 2022, newborn screening for G6PD enzyme activity was carried out in Huizhou city using the fluorescence quantitative method. Infants who tested positive during the initial screening were diagnosed using the nitroblue tetrazolium ratio method, while a subset of infants received further gene mutation analysis using the multicolor probe melting curve analysis method. RESULTS: A total of 1,291,274 newborns were screened and the screening rate has increased from 20.39% to almost 100%. In the 20-year period, 57,217 (4.43%) infants testing positive during the initial screening. Out of these infants, 49,779 (87%) were recalled for confirmatory testing. G6PD deficiency was confirmed in 39,261 of the recalled infants, indicating a positive predictive value of 78.87%. The estimated incidence rate of G6PD deficiency in the region was 3.49%, which was significantly higher than the average incidence rate of 2.1% in southern China. On the other hand, seven pathogenic G6PD variants were identified in the analysis of the 99 diagnosed infants with the most common being c.1388 G > A (48.5%), followed by c.95 A > G (19.2%), c.1376 G > T (15.2%), c.871 G > A (9.1%), c.1360 C > T (3.0%), c.392 G > T (3.0%), and c.487 G > A (1.0%). CONCLUSION: The incidence of G6PD deficiency in newborns in the Huizhou city was higher than the southern China average level, while the types and frequencies of gene mutations were found to vary slightly from other regions. Our findings suggested that free government screening and nearby diagnosis strategies could reduce the incidence of G6PD deficiency in the area.
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Deficiencia de Glucosafosfato Deshidrogenasa , Lactante , Humanos , Recién Nacido , Deficiencia de Glucosafosfato Deshidrogenasa/diagnóstico , Deficiencia de Glucosafosfato Deshidrogenasa/epidemiología , Deficiencia de Glucosafosfato Deshidrogenasa/genética , Tasa de Mutación , Glucosafosfato Deshidrogenasa/genética , Mutación , Tamizaje Neonatal , China/epidemiologíaRESUMEN
BACKGROUND AND OBJECTIVES: To investigate the prevalence, genotype and haematological characteristics of glucose-6-phosphate dehydrogenase (G6PD) deficiency in the blood donor population of Wuxi area (Jiangsu Province, China) and to assess the impact of their red blood cell (RBC) units on clinical transfusion. MATERIALS AND METHODS: We conducted genotyping and large-scale screening for G6PD enzyme activity in the blood donors of Wuxi City. In addition, we assessed the haematological parameters of G6PD-deficient and non-deficient blood donors, and investigated the adverse transfusion reactions in patients transfused with G6PD-deficient blood. RESULTS: We investigated 17,113 blood donors, among whom 44 (0.26%) were tested positive for G6PD deficiency. We identified 40 G6PD gene variants, among which c.1388G>A, c.1376G>T, c.1024C>T and c.95A>G were common. In addition, we identified two novel G6PD gene variants, c.1312G>A and c.1316G>A. The G6PD-deficient and non-deficient blood samples showed a significant difference in the RBC, mean corpuscular volume (MCV), mean corpuscular Hb (MCH), RBC distribution width, total bilirubin (TBIL), direct bilirubin (DBIL) and indirect bilirubin (IBIL) values. However, the two samples showed no significant difference in the haemolysis rate at the end of the storage period. Finally, transfusion with G6PD-deficient RBC units did not lead to any adverse transfusion reactions. CONCLUSION: The positive rate of G6PD deficiency in the blood donor population of Wuxi City is 0.26%, and the genetic variants identified in this population are consistent with the common genetic variants observed in the Chinese population. Blood centres can establish a database on G6PD-deficient blood donors and mark their RBC units to avoid their use for special clinical patients.
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BACKGROUND: It was hypothesized that glucose-6-phosphate dehydrogenase (G6PD) deficiency confers a protective effect against malaria infection, however, safety concerns have been raised regarding haemolytic toxicity caused by radical cure with 8-aminoquinolines in G6PD-deficient individuals. Malaria elimination and control are also complicated by the high prevalence of G6PD deficiency in malaria-endemic areas. Hence, accurate identification of G6PD deficiency is required to identify those who are eligible for malaria treatment using 8-aminoquinolines. METHODS: The prevalence of G6PD deficiency among 408 Thai participants diagnosed with malaria by microscopy (71), and malaria-negative controls (337), was assessed using a phenotypic test based on water-soluble tetrazolium salts. High-resolution melting (HRM) curve analysis was developed from a previous study to enable the detection of 15 common missense, synonymous and intronic G6PD mutations in Asian populations. The identified mutations were subjected to biochemical and structural characterisation to understand the molecular mechanisms underlying enzyme deficiency. RESULTS: Based on phenotypic testing, the prevalence of G6PD deficiency (< 30% activity) was 6.13% (25/408) and intermediate deficiency (30-70% activity) was found in 15.20% (62/408) of participants. Several G6PD genotypes with newly discovered double missense variants were identified by HRM assays, including G6PD Gaohe + Viangchan, G6PD Valladolid + Viangchan and G6PD Canton + Viangchan. A significantly high frequency of synonymous (c.1311C>T) and intronic (c.1365-13T>C and c.486-34delT) mutations was detected with intermediate to normal enzyme activity. The double missense mutations were less catalytically active than their corresponding single missense mutations, resulting in severe enzyme deficiency. While the mutations had a minor effect on binding affinity, structural instability was a key contributor to the enzyme deficiency observed in G6PD-deficient individuals. CONCLUSIONS: With varying degrees of enzyme deficiency, G6PD genotyping can be used as a complement to phenotypic screening to identify those who are eligible for 8-aminoquinolines. The information gained from this study could be useful for management and treatment of malaria, as well as for the prevention of unanticipated reactions to certain medications and foods in the studied population.
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Deficiencia de Glucosafosfato Deshidrogenasa , Malaria , Humanos , Deficiencia de Glucosafosfato Deshidrogenasa/epidemiología , Deficiencia de Glucosafosfato Deshidrogenasa/genética , Deficiencia de Glucosafosfato Deshidrogenasa/diagnóstico , Tailandia/epidemiología , Glucosafosfato Deshidrogenasa/genética , Glucosafosfato Deshidrogenasa/análisis , Malaria/epidemiología , Aminoquinolinas/efectos adversosRESUMEN
BACKGROUND: Testing for glucose-6-phosphate dehydrogenase (G6PD) deficiency is an important consideration regarding treatment for malaria. G6PD deficiency may lead to haemolytic anaemia during malaria treatment and, therefore, determining G6PD deficiency in malaria treatment strategies is extremely important. METHODS: This report presents the results of a scoping review and evidence and gap map for consideration by the Guideline Development Group for G6PD near patient tests to support radical cure of Plasmodium vivax. This scoping review has investigated common diagnostic tests for G6PD deficiency and important contextual and additional factors for decision-making. These factors include six of the considerations recommended by the World Health Organization (WHO) handbook for guideline development as important to determining the direction and strength of a recommendation, and included 'acceptability', 'feasibility,' 'equity,' 'valuation of outcomes,' 'gender' and 'human rights'. The aim of this scoping review is to inform the direction of future systematic reviews and evidence syntheses, which can then better inform the development of WHO recommendations regarding the use of G6PD deficiency testing as part of malaria treatment strategies. RESULTS: A comprehensive search was performed, including published, peer-reviewed literature for any article, of any study design and methodology that investigated G6PD diagnostic tests and the factors of 'acceptability', 'feasibility,' 'equity,' 'valuation of outcomes,' 'gender' and 'human rights'. There were 1152 studies identified from the search, of which 14 were determined to be eligible for inclusion into this review. The studies contained data from over 21 unique countries that had considered G6PD diagnostic testing as part of a malaria treatment strategy. The relationship between contextual and additional factors, diagnostic tests for G6PD deficiency and study methodology is presented in an overall evidence and gap, which showed that majority of the evidence was for the contextual factors for diagnostic tests, and the 'Standard G6PD (SD Biosensor)' test. CONCLUSIONS: This scoping review has produced a dynamic evidence and gap map that is reactive to emerging evidence within the field of G6PD diagnostic testing. The evidence and gap map has provided a comprehensive depiction of all the available literature that address the contextual and additional factors important for decision-making, regarding specific G6PD diagnostic tests. The majority of data available investigating the contextual factors of interest relates to quantitative G6PD diagnostic tests. While a formal qualitative synthesis of this data as part of a systematic review is possible, the data may be too heterogenous for this to be appropriate. These results can now be used to inform future direction of WHO Guideline Development Groups for G6PD near patient tests to support radical cure of P. vivax malaria.
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Pruebas Diagnósticas de Rutina , Deficiencia de Glucosafosfato Deshidrogenasa , Deficiencia de Glucosafosfato Deshidrogenasa/diagnóstico , Humanos , Pruebas Diagnósticas de Rutina/métodos , Pruebas Diagnósticas de Rutina/estadística & datos numéricos , Malaria Vivax/diagnóstico , Malaria Vivax/tratamiento farmacológico , Malaria/diagnóstico , Malaria/tratamiento farmacológicoRESUMEN
BACKGROUND: To interrupt residual malaria transmission and achieve successful elimination of Plasmodium falciparum in low-transmission settings, the World Health Organization (WHO) recommends the administration of a single dose of 0.25 mg/kg (or 15 mg/kg for adults) primaquine (PQ) combined with artemisinin-based combination therapy (ACT), without glucose-6-phosphate dehydrogenase (G6PD) testing. However, due to the risk of haemolysis in patients with G6PD deficiency (G6PDd), PQ use is uncommon. Thus, this study aimed to assess the safety of a single low dose of PQ administered to patients with G6PD deficiency. METHODS: An observational cohort study was conducted with patients treated for uncomplicated P. falciparum malaria with either single-dose PQ (0.25 mg/kg) (SLD PQ) + ACT or ACT alone. Microscopy-confirmed uncomplicated P. falciparum malaria patients visiting public health facilities in Arjo Didessa, Southwest Ethiopia, were enrolled in the study from September 2019 to November 2022. Patients with uncomplicated P. falciparum malaria were followed up for 28 days through clinical and laboratory diagnosis, such as measurements of G6PD levels and haemoglobin (Hb) concentrations. G6PD levels were measured by a quantiative CareSTART™ POCT S1 biosensor machine. Patient interviews were also conducted, and the type and frequency of clinical complaints were recorded. Hb data were taken on days (D) 7, 14, 21, and 28 following treatment with SLD-PQ + ACT or ACT alone. RESULTS: A total of 249 patients with uncomplicated P. falciparum malaria were enrolled in this study. Of these, 83 (33.3%) patients received ACT alone, and 166 (66.7%) received ACT combined with SLD-PQ treatment. The median age of the patients was 20 (IQR 28-15) years. G6PD deficiency was found in 17 (6.8%) patients, 14 males and 3 females. There were 6 (7.2%) and 11 (6.6%) phenotypic G6PD-deficient patients in the ACT alone and ACT + SLD-PQ arms, respectively. The mean Hb levels in patients treated with ACT + SLD-PQ were reduced by an average of 0.45 g/dl (95% CI = 0.39 to 0.52) in the posttreatment phase (D7) compared to a reduction of 0.30 g/dl (95% CI = 0.14 to - 0.47) in patients treated with ACT alone (P = 0.157). A greater mean Hb reduction was observed on day 7 in the G6PDd ACT + SLD-PQ group (- 0.60 g/dL) than in the G6PDd ACT alone group (- 0.48 g/dL); however, there was no statistically significant difference (P = 0.465). Overall, D14 losses were 0.10 g/dl (95% CI = - 0.00 to 0.20) and 0.05 g/dl (95% CI = - 0.123 to 0.22) in patients with and without SLD-PQ, respectively (P = 0.412). CONCLUSIONS: This study's findings indicate that using SLD-PQ in combination with ACT is safe for uncomplicated P. falciparum malaria regardless of the patient's G6PD status in Ethiopian settings. Caution should be taken in extrapolating this finding in other settings with diverse G6DP phenotypes.
Asunto(s)
Antimaláricos , Artemisininas , Deficiencia de Glucosafosfato Deshidrogenasa , Hemoglobinas , Malaria Falciparum , Primaquina , Malaria Falciparum/tratamiento farmacológico , Humanos , Etiopía , Masculino , Primaquina/administración & dosificación , Primaquina/uso terapéutico , Primaquina/efectos adversos , Adulto , Antimaláricos/administración & dosificación , Antimaláricos/uso terapéutico , Femenino , Estudios Longitudinales , Hemoglobinas/análisis , Adolescente , Adulto Joven , Deficiencia de Glucosafosfato Deshidrogenasa/complicaciones , Persona de Mediana Edad , Niño , Artemisininas/administración & dosificación , Artemisininas/uso terapéutico , Estudios de Cohortes , Preescolar , Plasmodium falciparum/efectos de los fármacosRESUMEN
BACKGROUND: Plasmodium vivax relapses due to dormant liver hypnozoites can be prevented with primaquine. However, the dose must be adjusted in individuals with glucose-6-phosphate-dehydrogenase (G6PD) deficiency. In French Guiana, assessment of G6PD activity is typically delayed until day (D)14 to avoid the risk if misclassification. This study assessed the kinetics of G6PD activity throughout P. vivax infection to inform the timing of treatment. METHODS: For this retrospective monocentric study, data on G6PD activity between D1 and D28 after treatment initiation with chloroquine or artemisinin-based combination therapy were collected for patients followed at Cayenne Hospital, French Guiana, between January 2018 and December 2020. Patients were divided into three groups based on the number of available G6PD activity assessments: (i) at least two measurements during the P. vivax malaria infection; (ii) two measurements: one during the current infection and one previously; (iii) only one measurement during the malaria infection. RESULTS: In total, 210 patients were included (80, 20 and 110 in groups 1, 2 and 3, respectively). Data from group 1 showed that G6PD activity remained stable in each patient over time (D1, D3, D7, D14, D21, D28). None of the patients with normal G6PD activity during the initial phase (D1-D3) of the malaria episode (n = 44) was categorized as G6PD-deficient at D14. Patients with G6PD activity < 80% at D1 or D3 showed normal activity at D14. Sex and reticulocyte count were statistically associated with G6PD activity variation. In the whole sample (n = 210), no patient had severe G6PD deficiency (< 10%) and only three between 10 and 30%, giving a G6PD deficiency prevalence of 1.4%. Among the 100 patients from group 1 and 2, 30 patients (26.5%) were lost to follow-up before primaquine initiation. CONCLUSIONS: In patients treated for P. vivax infection, G6PD activity did not vary over time. Therefore, G6PD activity on D1 instead of D14 could be used for primaquine dose-adjustment. This could allow earlier radical treatment with primaquine, that could have a public health impact by decreasing early recurrences and patients lost to follow-up before primaquine initiation. This hypothesis needs to be confirmed in larger prospective studies.
Asunto(s)
Antimaláricos , Glucosafosfato Deshidrogenasa , Malaria Vivax , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Antimaláricos/uso terapéutico , Artemisininas/uso terapéutico , Cloroquina/uso terapéutico , Guyana Francesa/epidemiología , Glucosafosfato Deshidrogenasa/metabolismo , Deficiencia de Glucosafosfato Deshidrogenasa/epidemiología , Deficiencia de Glucosafosfato Deshidrogenasa/complicaciones , Cinética , Malaria Vivax/tratamiento farmacológico , Plasmodium vivax/efectos de los fármacos , Plasmodium vivax/fisiología , Primaquina/uso terapéutico , Estudios Retrospectivos , Anciano de 80 o más AñosRESUMEN
BACKGROUND: Primaquine (PQ) is the prototype 8-aminoquinoline drug, a class which targets gametocytes and hypnozoites. The World Health Organization (WHO) recommends adding a single low dose of primaquine to the standard artemisinin-based combination therapy (ACT) in order to block malaria transmission in regions with low malaria transmission. However, the haemolytic toxicity is a major adverse outcome of primaquine in glucose-6-phosphate dehydrogenase (G6PD)-deficient subjects. This study aimed to characterize the pharmacokinetic properties of primaquine and its major metabolites in G6PD-deficient subjects. METHODS: A single low-dose of primaquine (0.4-0.5 mg/kg) was administered in twenty-eight African males. Venous and capillary plasma were sampled up to 24 h after the drug administration. Haemoglobin levels were observed up to 28 days after drug administration. Only PQ, carboxy-primaquine (CPQ), and primaquine carbamoyl-glucuronide (PQCG) were present in plasma samples and measured using liquid chromatography mass spectrometry. Drug and metabolites' pharmacokinetic properties were investigated using nonlinear mixed-effects modelling. RESULTS: Population pharmacokinetic properties of PQ, CPQ, and PQCG can be described by one-compartment disposition kinetics with a transit-absorption model. Body weight was implemented as an allometric function on the clearance and volume parameters for all compounds. None of the covariates significantly affected the pharmacokinetic parameters. No significant correlations were detected between the exposures of the measured compounds and the change in haemoglobin or methaemoglobin levels. There was no significant haemoglobin drop in the G6PD-deficient patients after administration of a single low dose of PQ. CONCLUSIONS: A single low-dose of PQ was haematologically safe in this population of G6PD-normal and G6PD-deficient African males without malaria. Trial registration NCT02535767.
Asunto(s)
Antimaláricos , Deficiencia de Glucosafosfato Deshidrogenasa , Primaquina , Adolescente , Adulto , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Antimaláricos/farmacocinética , Antimaláricos/sangre , Antimaláricos/administración & dosificación , Primaquina/farmacocinética , Primaquina/sangre , Primaquina/administración & dosificaciónRESUMEN
Glucose-6-phosphate dehydrogenase (G6PD) is involved in triple-negative breast cancer (TNBC) progression. Metabolic crosstalk between cancer cells and tumor-associated macrophages mediates tumor progression in TNBC. Molecular biological methods were applied to clarify the mechanism of the crosstalk between TNBC cells and M2 macrophages. In the present study, we verified that G6PD overexpression drives M2 macrophage polarization by directly combining with phospho-STAT1 and upregulating CCL2 and TGF-ß1 secretion in TNBC cells. In turn, M2-like TAMs activated TNBC cells through IL-10 secretion, providing feedback to upregulate G6PD and promote TNBC cell migration and proliferation in vitro. Furthermore, we found that 6-AN (a specific inhibitor of G6PD) not only suppressed the cancer-driven polarization of macrophages toward the M2 phenotype but also inhibited the inherent M2 polarization of macrophages. Targeting the G6PD-regulated pentose phosphate pathway restrained TNBC progression and M2-type polarization of macrophages in vitro and in vivo.
Asunto(s)
Glucosafosfato Deshidrogenasa , Neoplasias de la Mama Triple Negativas , Humanos , Línea Celular Tumoral , Glucosafosfato Deshidrogenasa/genética , Glucosafosfato Deshidrogenasa/metabolismo , Macrófagos/metabolismo , Neoplasias de la Mama Triple Negativas/genética , Microambiente TumoralRESUMEN
BACKGROUND: Glucose-6-phosphate dehydrogenase (G6PD) plays an important role in vascular smooth muscle cell (VSMC) phenotypic switching, which is an early pathogenic event in various vascular remodeling diseases (VRDs). However, the underlying mechanism is not fully understood. METHODS: An IPâLCâMS/MS assay was conducted to identify new binding partners of G6PD involved in the regulation of VSMC phenotypic switching under platelet-derived growth factor-BB (PDGF-BB) stimulation. Co-IP, GST pull-down, and immunofluorescence colocalization were employed to clarify the interaction between G6PD and voltage-dependent anion-selective channel protein 1 (VDAC1). The molecular mechanisms involved were elucidated by examining the interaction between VDAC1 and apoptosis-related biomarkers, as well as the oligomerization state of VDAC1. RESULTS: The G6PD level was significantly elevated and positively correlated with the synthetic characteristics of VSMCs induced by PDGF-BB. We identified VDAC1 as a novel G6PD-interacting molecule essential for apoptosis. Specifically, the G6PD-NTD region was found to predominantly contribute to this interaction. G6PD promotes VSMC survival and accelerates vascular neointimal hyperplasia by inhibiting VSMC apoptosis. Mechanistically, G6PD interacts with VDAC1 upon stimulation with PDGF-BB. By competing with Bax for VDAC1 binding, G6PD reduces VDAC1 oligomerization and counteracts VDAC1-Bax-mediated apoptosis, thereby accelerating neointimal hyperplasia. CONCLUSION: Our study showed that the G6PD-VDAC1-Bax axis is a vital switch in VSMC apoptosis and is essential for VSMC phenotypic switching and neointimal hyperplasia, providing mechanistic insight into early VRDs.
Asunto(s)
Glucosafosfato Deshidrogenasa , Músculo Liso Vascular , Canal Aniónico 1 Dependiente del Voltaje , Humanos , Hiperplasia/metabolismo , Hiperplasia/patología , Becaplermina/genética , Becaplermina/metabolismo , Proliferación Celular , Proteína X Asociada a bcl-2/metabolismo , Glucosafosfato Deshidrogenasa/metabolismo , Músculo Liso Vascular/metabolismo , Cromatografía Liquida , Espectrometría de Masas en Tándem , Neointima/genética , Neointima/metabolismo , Neointima/patología , Apoptosis , Miocitos del Músculo Liso/metabolismo , Movimiento Celular/genética , Células Cultivadas , FenotipoRESUMEN
Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common blood disorder, presenting multiple symptoms, including hemolytic anemia. It affects 400 million people worldwide, with more than 160 single mutations reported in G6PD. The most severe mutations (about 70) are classified as class I, leading to more than 90% loss of activity of the wild-type G6PD. The crystal structure of G6PD reveals these mutations are located away from the active site, concentrating around the noncatalytic NADP+-binding site and the dimer interface. However, the molecular mechanisms of class I mutant dysfunction have remained elusive, hindering the development of efficient therapies. To resolve this, we performed integral structural characterization of five G6PD mutants, including four class I mutants, associated with the noncatalytic NADP+ and dimerization, using crystallography, small-angle X-ray scattering (SAXS), cryogenic electron microscopy (cryo-EM), and biophysical analyses. Comparisons with the structure and properties of the wild-type enzyme, together with molecular dynamics simulations, bring forward a universal mechanism for this severe G6PD deficiency due to the class I mutations. We highlight the role of the noncatalytic NADP+-binding site that is crucial for stabilization and ordering two ß-strands in the dimer interface, which together communicate these distant structural aberrations to the active site through a network of additional interactions. This understanding elucidates potential paths for drug development targeting G6PD deficiency.