Impaired inflammasome activation and bacterial clearance in G6PD deficiency due to defective NOX/p38 MAPK/AP-1 redox signaling.

Glucose-6-phosphate dehydrogenase (G6PD) is the rate-limiting enzyme of the pentose phosphate pathway that modulates cellular redox homeostasis via the regeneration of NADPH. G6PD-deficient cells have a reduced ability to induce the innate immune response, thus increasing host susceptibility to pathogen infections. An important part of the immune response is the activation of the inflammasome. G6PD-deficient peripheral blood mononuclear cells (PBMCs) from patients and human monocytic (THP-1) cells were used as models to investigate whether G6PD modulates inflammasome activation. A decreased expression of IL-1ß was observed in both G6PD-deficient PBMCs and PMA-primed G6PD-knockdown (G6PD-kd) THP-1 cells upon lipopolysaccharide (LPS)/adenosine triphosphate (ATP) or LPS/nigericin stimulation. The pro-IL-1ß expression of THP-1 cells was decreased by G6PD knockdown at the transcriptional and translational levels in an investigation of the expression of the inflammasome subunits. The phosphorylation of p38 MAPK and downstream c-Fos expression were decreased upon G6PD knockdown, accompanied by decreased AP-1 translocation into the nucleus. Impaired inflammasome activation in G6PD-kd THP-1 cells was mediated by a decrease in the production of reactive oxygen species (ROS) by NOX signaling, while treatment with hydrogen peroxide (H2O2) enhanced inflammasome activation in G6PD-kd THP-1 cells. G6PD knockdown decreased Staphylococcus aureus and Escherichia coli clearance in G6PD-kd THP-1 cells and G6PD-deficient PBMCs following inflammasome activation. These findings support the notion that enhanced pathogen susceptibility in G6PD deficiency is, in part, due to an altered redox signaling, which adversely affects inflammasome activation and the bactericidal response.

Hepatic transcriptional profiling response to fava bean-induced oxidative stress in glucose-6-phosphate dehydrogenase-deficient mice.

Favism is an acute hemolytic syndrome caused by the ingestion of fava bean (FB) in glucose 6-phosphate dehydrogenase (G6PD) deficient individuals. However, little is known about the global transcripts alteration in liver tissue after FB ingestion in G6PD-normal and -deficient states. In this study, deep sequencing was used to analyze liver genes expression alterations underlying the effects of FB in C3H (Wild Type, WT) and G6PD-deficient (G6PDx) mice and to evaluate and visualize the collective annotation of a list of genes to Gene Ontology (GO) terms associated with favism. Our results showed that FB resulted in a decrease of glutathione (GSH)-to-oxidized glutathione (GSSG) ratio and an increase of malondialdehyde (MDA) both in the G6PDx and WT-control check (CK) mice plasma. Significantly, liver transcript differences were observed between the control and FB-treated groups of both WT and G6PDx mice. A total of 320 differentially expressed transcripts were identified by comparison of G6PDx-CK with WT-CK and were associated with immune response and oxidation-reduction function. A total of 149 differentially expressed genes were identified by comparison of WT-FB with WT-CK. These genes were associated with immune response, steroid metabolic process, creatine kinase activity, and fatty acid metabolic process. A total of 438 differential genes were identified by comparing G6PDx-FB with G6PD-CK, associated with the negative regulation of fatty acid metabolic process, endoplasmic reticulum, iron binding, and glutathione transferase activity. These findings indicate that G6PD mutations may affect the functional categories such as immune response and oxidation-reduction.

Co-occurrence of biphenotypic acute leukaemia, glucose 6-phosphate dehydrogenase deficiency and haemoglobin E trait in a single child.

Acute leukaemias occur as the result of clonal expansion subsequent to transformation and arrest at a normal differentiation stage of haematopoietic precursors, which commit to a single lineage, such as myeloid or B-lymphoid or T-lymphoid cells. Biphenotypic acute leukaemia (BAL) constitutes a biologically different group of leukaemia arising from a precursor stem cell and co-expressing more than one lineage specific marker. The present report describes a child with unusual co-occurrence of biphenotypic (B-precursor cell and Myeloid) acute leukaemia, haemoglobin E trait and glucose 6-phosphate dehydrogenase (G6-PD) deficiency. To the best of our knowledge, this constellation of haematological conditions in a single child has never been described before.

Neutrophil functional disorder in childhood.

Neutrophil functional disorders thought to be uncommon, yet important as a cause of morbidity and mortality in infants and children. During the first years of life, when the immune system is still not completely mature, when the viral infections are frequent and antibiotic overuse can damage and alter the immune response, the inadequate nutrition followed with iron deficient anemia and malnutrition can lead the child`s organism in state of immunodeficiency. Sometimes is difficult to distinguish at the beginning weather the cause of patient suffering from frequent infections is existing of primary immunodeficiency disorder or the cause of the immunodeficiency state is just from exogenous factors. Fortunately, primary immune deficiencies are rare diseases and only 6-7% of all of them, due to the neutrophilic functional disorders. Unfortunately, many exogenous and environmental factors have influence to the immune system, and the percentage of secondary caused neutrophilic functional disorders is much higher and should be considered when children are investigated for immunodeficiency. So, when to suspect neutrophil functional disorder? The hallmarks for diseases related to the neutrophilic functional disorders are discussed in this article.

Cytokine responses of TNF-α, IL-6, and IL-10 in G6PD-deficient infants.

G6PD-deficient adults are reported to be susceptible to severe infection, and decreased cytokine responses have been postulated as the underlying mechanism. However, investigating the association of G6PD deficiency and cytokine responses during infancy is lacking. The current study aims to determine whether cytokine responses of tumor necrosis factor ()-α, interleukins (IL)-6, and IL-10 are impaired in the G6PD-deficient infants. Upon agreements with informed consents, peripheral blood mononuclear cells (PBMCs) of enrolled infants were collected twice at 1 month and 1 year of age. PBMCs were then stimulated with toll-like receptor (TLR) agonists-including PAM3csk4 for TLR1-2, poly (I:C) for TLR3, and lipopolysaccharide for TLR4-to analyze the expression of TNF-α, IL-6, and IL-10. Males (P = .004) and phototherapy during neonatal period (P = .008) were more common among G6PD-deficient infants than G6PD-normal subjects. After the stimulation of TLR agonists, there was no significant difference in the expression of TNF-α, IL-6, and IL-10 between PBMCs of G6PD-deficient and -normal infants at both 1 month and 1 year of age. In conclusion, the clinical characteristics of G6PD-deficient infants are different from those of G6PD-normal subjects. The data suggest that the innate immune responses to TLR agonists in G6PD-deficient infants are not different from those of G6PD-normal infants.

Endotoxemia down-regulates bone marrow lymphopoiesis but stimulates myelopoiesis: the effect of G6PD deficiency.

Bone marrow (BM) dysfunction is an important component of immunomodulation. This study investigated alterations in cell content, apoptotic responses, and cell proliferation in BM, blood, and spleen in endotoxemic mice (LPS from Escherichia coli). As the decreased antioxidant status associated with glucose-6-phosphate dehydrogenase (G6PD) deficiency has been shown to modulate the innate immune response, we also tested whether a G6PD mutation (80% decrease in cellular enzyme activity) alters BM responses during endotoxemia. LPS decreased BM myeloid (CD45(+)CD11b(+)) and B lymphoid (CD45(+)CD19(+)CD11b(-)) cell content compared with controls. In contrast, LPS increased CD11b(+) myeloid but decreased T and B cell counts in the circulation. Endotoxemia inhibited spontaneous, heat shock, and H(2)O(2)-induced apoptosis as well as proliferative activity in BM lymphoid cells. In contrast, BM myeloid cell apoptosis was not altered, and their proliferative activity was increased during endotoxemia. Following LPS, splenic myeloid cell content was increased, and T and B cell content was unchanged; furthermore, splenocytes showed increased apoptosis compared with controls. BM cell content, including lymphoid and myeloid cells, was greater in G6PD mutant than wild-type (WT) mice, and LPS decreased BM cell counts to a greater degree in mutant than WT mice. Endotoxemia caused widespread inhibition of BM cytokine and chemokine production; however, IL-6 production was increased compared with controls. LPS-induced IL-6 production was decreased in G6PD mutant animals compared with WT. This study indicates that endotoxin inversely affects BM myeloid and lymphoid cell production. LPS-induced down-regulation of B cell production contributes to the generalized lymphopenia and lymphocyte dysfunction observed following nonspecific immune challenges.

Production of inflammatory molecules in peripheral blood mononuclear cells from severely glucose-6-phosphate dehydrogenase-deficient subjects.

OBJECTIVE: We have previously demonstrated that Mediterranean glucose-6-phosphate dehydrogenase (G6PD)-deficient peripheral blood mononuclear cells (PBMC) respond to mitogenic stimuli with a reduced cholesterol synthesis and growth. In the present study, we have investigated the release of inflammatory molecules by PBMC following a mitogenic stimulus, as well as the transformation to foam cells of monocyte-derived macrophages from severely G6PD-deficient and normal subjects. METHODS AND RESULTS: PBMC from G6PD-deficient subjects produced interleukin (IL)-1beta and IL-6 to a lower extent compared with normal subjects. 5-Hydroxyeicosatetraenoic acid, a primary product of 5-lipoxygenase, was slightly decreased. Tumour necrosis factor-alpha and IL-1beta secretion was significantly reduced in monocyte-derived macrophages. No difference was found in IL-10 secretion, whereas transforming growth factor-beta was invariably found to be significantly higher in G6PD-deficient cells. In cells incubated with acetylated low-density lipoprotein, cholesterol esterification and its storage in lipid droplets were lower than in normal G6PD cells. CONCLUSIONS: We conclude that by reducing the secretion of inflammatory molecules by PBMC and increasing the secretion of transforming growth factor-beta and the capability of monocyte-derived macrophages to accumulate lipid droplets and convert into foam cells, G6PD deficiency may confer a partial protection against atherosclerosis leading to the reduced risk of cardiovascular diseases reported in G6PD-deficient subjects.

Augmented IL-10 production and redox-dependent signaling pathways in glucose-6-phosphate dehydrogenase-deficient mouse peritoneal macrophages.

Glucose-6-phosphate dehydrogenase (G6PD) supports cellular antioxidant pathways. G6PD deficiency is associated with malaria protection but was shown to worsen the clinical course to injury. This study tested whether G6PD deficiency manifests in altered cytokine responses using peritoneal macrophages from a G6PD-deficient mouse model with a degree of defect similar to the common type A(-) human G6PD deficiency. Lipopolysaccharide (LPS)-induced interleukin (IL)-10 and IL-12 production was doubled in G6PD-deficient macrophages compared with wild-type (WT). Protein kinase C (PKC) activation by phorbol-ester prior to LPS resulted in a fivefold greater IL-10 production in G6PD-deficient macrophages compared with WT. Interferon-gamma treatment prior to LPS augmented IL-12 production in G6PD-deficient and WT macrophages and partially inhibited IL-10 production by G6PD-deficient macrophages. The antioxidants (N-acetyl-L-cysteine and glutathione ethyl-ester) blunted IL-10 and IL-12 production, indicating a role for oxidative stress in the observed response differences between deficient and WT macrophages. LPS-induced activation of nuclear factor-kappaB, cyclic adenosine monophosphate response element-binding protein, and specificity protein 3 was augmented in G6PD-deficient cells compared with WT. The PKCdelta inhibitor Rottlerin inhibited IL-10 and IL-12 production at different 50% effective-dose concentrations between deficient and WT macrophages, indicating elevated PKCdelta activity in deficient cells. This study reveals that activated G6PD-deficient macrophages display an augmented production of cytokines with a prominent impact on IL-10 production. The altered cytokine responses are associated with augmented activation of redox-dependent transcription factors and PKCdelta. Alterations in signaling pathways and associated changes in cytokine production may play a role in modulating the inflammatory responses following bacterial or malarial infections in G6PD deficiency.

Dominance of high-producing interleukin 6 and low-producing interleukin 10 and interferon gamma alleles in glucose-6-phosphate dehydrogenase-deficient trauma patients.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency, a condition associated with malaria resistance, is a common genetic polymorphism. Decreased interleukin (IL)-10 production was demonstrated in vivo and in vitro in the African and Mediterranean forms of G6PD deficiencies. We hypothesized that low-producing IL-10 alleles are more abundant in the G6PD-deficient than nondeficient population. One hundred eleven men with African American ancestry were tested for G6PD deficiency (Type A-202/376) and for the cytokine gene promoter polymorphisms of IL-10 (-1082 G/A, -819 T/C, and -592 A/C), tumor necrosis factor (TNF)-alpha (-308 G/A), transforming growth factor (TGF)-beta1 (C/T codon 10 and C/G codon 25), IL-6 (-174 G/C), and interferon (IFN)-gamma (+874 A/T). There were no differences in the allele frequencies for TNF-alpha, IL-6, or TGF-beta1 between the G6PD-deficient and nondeficient population. In contrast, the low-producing IL-10 alleles (-592A) and low-producing IFN-gamma (+874A) allele frequencies were greater in G6PD-deficient than nondeficient samples (P = 0.035 and 0.009). Seventy-one percent of G6PD-deficient and 50% of nondeficient samples carried the high-producing IL-6(G) allele with low-producing IL-10(A) allele (P = 0.03). Furthermore, 95% of deficient and 81% of nondeficient samples carried the IL-6(G) allele together with low-producing IFN-gamma(A) allele (P = 0.017). These investigations indicate a predominant presence of high-producing IL-6 alleles together with low-producing IL-10 and IFN-gamma alleles in individuals with ancestry from malaria-endemic regions. The frequency of low-producing IL-10 genotypes is greater in the G6PD-deficient compared with nondeficient patients. The fact that these genetic differences are preserved in the current African American G6PD-deficient population indicates their potential role in pathophysiological processes in the absence of the selective pressure caused by tropical diseases.

[Influence of human genetic variants on resistance and immunity against malaria]. / Einfluss genetischer Varianten des Menschen auf Resistenz und Immunität gegen Malaria.

Certain human genetic variants occur on-ly in areas endemic for malaria. They protect against fatal malaria complications and cause inhibition of growth or development of malaria parasites in vitro. Among these are the haemoglobins (Hb) S and C, alpha-thalassaemias, glucose-6-phosphate dehydrogenase deficiency, as well as a deletion in the erythrocyte band 3 protein. Evidence for similar effects has been obtained for HbD and HbE, glycophorins A and C as well as for a number of immunologically relevant molecules such as human leukocyte antigens,tumour-necrosis-factor a and the inducible nitric oxide synthase. The findings indicate that malaria in endemic areas has caused a substantial selection of the human genome.

Toxoplasmosis in a group of glucose-6-phosphate dehydrogenase deficient patients.

OBJECTIVE: This was a retrospective study that aimed at evaluating the relative risk of Toxoplasma infection in patients with glucose-6-phosphate dehydrogenase deficiency as compared to a control group with no glucose-6-phosphate dehydrogenase deficiency. METHODS: Ninety-one blood donor volunteers had serology testing from Toxoplasma gondii and were screened for glucose-6-phosphate dehydrogenase deficiency by a qualitative method using fluorescent spot test. They were all males and their ages ranged from 17 to 52 years. RESULTS: Fifty-three persons (58%) were glucose-6-phosphate dehydrogenase deficient and 38 (42%) were glucose-6-phosphate dehydrogenase normal. In the glucose-6-phosphate dehydrogenase deficient group, 31 (58.5%) had positive titers for Toxoplasma; while in the glucose-6-phosphate dehydrogenase normal group 9 persons (24%) had positive titers for Toxoplasma. The relative risk of infection was 2.5 times more in the glucose-6-phosphate dehydrogenase deficient group, a statistically significant difference with a p value of 0.002. CONCLUSION: Glucose-6-phosphate dehydrogenase deficiency seems to increase the risk for Toxoplasma infection by 2.5 fold probably due to decreased killing effect, of phagocytic cells.

Neutrophil-mediated tumor cell cytotoxicity: role of the peroxidase system.

A cytotoxic effect of human neutrophils on mammalian tumor cells is demonstrated. Cytotoxicity depends on the presence of intact neutrophils, phagocytosable particles, and a halide cofactor and is inhibited by azide, cyanide, and catalase. Neutrophils from patients with myeloperoxidase (MPO) deficiency or defective H1O2 production are not cytotoxic, but activity is resotred by addition of purified MPO or H2O2 respectively. The findings support a mechanism involving the phagocytosis-induced extracellular release of MPO and H2O2 and their reation with a halide cofactor to damage the target cells.