Contrasting effects of NADPH oxidases on the fungal hyphae growth and immune responses in Pleurotus ostreatus.

Pleurotus ostreatus is one of the most consumed mushroom species, as it serves as a high-quality food, favors a rich secondary metabolism, and has remarkable adaptability to the environment and predators. In this study, we investigated the function of two key reactive oxygen species producing enzyme NADPH oxidase (PoNoxA and PoNoxB) in P. ostreatus hyphae growth, metabolite production, signaling pathway activation, and immune responses to different stresses. Characterization of the Nox mutants showed that PoNoxB played an important role in the hyphal formation of the multicellular structure, while PoNoxA regulated apical dominance. The ability of P. ostreatus to tolerate a series of abiotic stress conditions (e.g., osmotic, oxidative, membrane, and cell-wall stresses) and mechanical damage repair was enhanced with PoNoxA over-expression. PoNoxB had a greater responsibility in regulating the polysaccharide composition of the cell wall and methyl jasmonate and gibberellin GA1 biosynthesis, and improved mushroom resistance against Tyrophagus putrescentiae. Moreover, mutants were involved in the jasmonate and GA signaling pathway, and toxic protein defense metabolite production. Our findings shed light on how the oyster mushroom senses stress signals and responds to adverse environments by the complex regulators of Noxs.

Diapocynin treatment induces functional and structural improvements in an advanced disease state in the mdx5Cv mice.

Duchenne muscular dystrophy (DMD) is the most common muscular disorder affecting children. It affects nearly 1 male birth over 5000. Oxidative stress is a pervasive feature in the pathogenesis of DMD. Recent work shows that the main generators of ROS are NADPH oxidases (NOX), suggesting that they are an early and promising target in DMD. In addition, skeletal muscles of mdx mice, a murine model of DMD, overexpress NOXes. We investigated the impact of diapocynin, a dimer of the NOX inhibitor apocynin, on the chronic disease phase of mdx5Cv mice. Treatment of these mice with diapocynin from 7 to 10 months of age resulted in decreased hypertrophy of several muscles, prevented force loss induced by tetanic and eccentric contractions, improved muscle and respiratory functions, decreased fibrosis of the diaphragm and positively regulated the expression of disease modifiers. These encouraging results ensure the potential role of diapocynin in future treatment strategies.

NADPH Oxidases in Neurodegenerative Disorders: Mechanisms and Therapeutic Opportunities.

Significance: The nicotinamide adenine dinucleotide phosphate oxidase (NOX) enzyme family, located in the central nervous system, is recognized as a source of reactive oxygen species (ROS) in the brain. Despite its importance in cellular processes, excessive ROS generation leads to cell death and is involved in the pathogenesis of neurodegenerative disorders. Recent advances: NOX enzymes contribute to the development of neurodegenerative diseases, such as Parkinson's disease (PD), Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), and stroke, highlighting their potential as targets for future therapeutic development. This review will discuss NOX's contribution and therapeutic targeting potential in neurodegenerative diseases, focusing on PD, AD, ALS, and stroke. Critical issues: Homeostatic and physiological levels of ROS are crucial for regulating several processes, such as development, memory, neuronal signaling, and vascular homeostasis. However, NOX-mediated excessive ROS generation is deeply involved in the damage of DNA, proteins, and lipids, leading to cell death in the pathogenesis of a wide range of diseases, namely neurodegenerative diseases. Future directions: It is essential to understand the role of NOX homologs in neurodegenerative disorders and the pathological mechanisms undergoing neurodegeneration mediated by increased levels of ROS. This further knowledge will allow the development of new specific NOX inhibitors and their application for neurodegenerative disease therapeutics.

Curcumin Modulates NOX Gene Expression and ROS Production via P-Smad3C in TGF-ß-Activated Hepatic Stellate Cells.

Background: Liver fibrosis, associated with hepatic stellate cells (HSCs), occurs when a healthy liver sustains damage, thereby impairing its function. NADPH oxidases (NOXs), specifically isoforms 1, 2, and 4, play a role in reactive oxygen species (ROS) production during hepatic injuries, resulting in fibrosis. Curcumin has shown strong potential in mitigating liver fibrosis. Our research aimed to investigate the effects of curcumin on lowering NOX and ROS levels. This compound was also studied for its effects on NOXs, ROS concentrations through the inhibition of Smad3 phosphorylation in transforming growth factor beta (TGF-ß)-activated human HSCs. Methods: MTT assay investigated the cytotoxic effects of curcumin on HSCs. The cells were activated by exposure to TGF-ß (2 ng/mL) for 24 hours. After activating, the cells were treated with curcumin at 25-150 µM concentrations. After administering curcumin to the cells, we employed RT-PCR and Western blot techniques to evaluate the related gene and protein expression levels. This evaluation was primarily focused on the mRNA expression levels of NOX1, NOX2, NOX4 and phosphorylated Smad3C. Results: The mRNA expression level of aforesaid NOXs as well as α-smooth muscle actin (α-SMA), collagen1-α, and ROS levels were significantly reduced following 100 µM curcumin treatment. Furthermore, curcumin significantly decreased the p-Smad3C protein level in TGF-ß-activated cells, with fold changes of 3 and 2 observed at 75 and 100 µM, respectively. Conclusion: Curcumin decreased the levels of ROS and NOX, as well as the expression of α-SMA and collagen1-α. The primary mechanism for this reduction could be linked to the level of p-Smad3C. Hence, curcumin could serve as an effective therapeutic agent for liver fibrosis.

Particulate matter stimulates the NADPH oxidase system via AhR-mediated epigenetic modifications.

Stimulation of human keratinocytes with particulate matter 2.5 (PM2.5) elicits complex signaling events, including a rise in the generation of reactive oxygen species (ROS). However, the mechanisms underlying PM2.5-induced ROS production remain unknown. Here, we show that PM2.5-induced ROS production in human keratinocytes is mediated via the NADPH oxidase (NOXs) system and the Ca2+ signaling pathway. PM2.5 treatment increased the expression of NOX1, NOX4, and a calcium-sensitive NOX, dual oxidase 1 (DUOX1), in human epidermal keratinocyte cell line. PM2.5 bound to aryl hydrocarbon receptor (AhR), and this complex bound to promoter regions of NOX1 and DUOX1, suggesting that AhR acted as a transcription factor of NOX1 and DUOX1. PM2.5 increased the transcription of DUOX1 via epigenetic modification. Moreover, a link between DNA demethylase and histone methyltransferase with the promoter regions of DUOX1 led to an elevation in the expression of DUOX1 mRNA. Interestingly, PM2.5 increased NOX4 expression and promoted the interaction of NOX4 and Ca2+ channels within the cytoplasmic membrane or endoplasmic reticulum, leading to Ca2+ release. The increase in intracellular Ca2+ concentration activated DUOX1, responsible for ROS production. Our findings provide evidence for a PM2.5-mediated ROS-generating system network, in which increased NOX1, NOX4, and DUOX1 expression serves as a ROS signal through AhR and Ca2+ activation.

Gene Expression and Prognostic Value of NADPH Oxidase Enzymes in Breast Cancer.

NADPH oxidase enzymes (NOX) are involved in all stages of carcinogenesis, but their expression levels and prognostic value in breast cancer (BC) remain unclear. Thus, we aimed to assess the expression and prognostic value of NOX enzymes in BC samples using online databases. For this, mRNA expression from 290 normal breast tissue samples and 1904 BC samples obtained from studies on cBioPortal, Kaplan-Meier Plotter, and The Human Protein Atlas were analyzed. We found higher levels of NOX2, NOX4, and Dual oxidase 1 (DUOX1) in normal breast tissue. NOX1, NOX2, and NOX4 exhibited higher expression in BC, except for the basal subtype, where NOX4 expression was lower. DUOX1 mRNA levels were lower in all BC subtypes. NOX2, NOX4, and NOX5 mRNA levels increased with tumor progression stages, while NOX1 and DUOX1 expression decreased in more advanced stages. Moreover, patients with low expression of NOX1, NOX4, and DUOX1 had lower survival rates than those with high expression of these enzymes. In conclusion, our data suggest an overexpression of NOX enzymes in breast cancer, with certain isoforms showing a positive correlation with tumor progression.

Superoxide signalling and antioxidant processing in the plant nucleus.

The superoxide anion radical (O2•-) is a one-electron reduction product of molecular oxygen. Compared to other forms of reactive oxygen species (ROS), superoxide has limited reactivity. Nevertheless, superoxide reacts with nitic oxide, ascorbate and the iron moieties of [Fe-S] cluster-containing proteins. Superoxide has largely been neglected as a signalling molecule in the plant literature in favour of the most stable ROS form, hydrogen peroxide. However, superoxide can accumulate in plant cells, particularly in meristems, where superoxide dismutase activity and ascorbate accumulation are limited (or absent), or when superoxide is generated within the lipid environment of membranes. Moreover, oxidation of the nucleus in response to environmental stresses is a widespread phenomenon. Superoxide is generated in many intracellular including mitochondria, chloroplasts and on the apoplastic/cell wall face of the plasma membrane. However, nuclear superoxide production and functions remain poorly documented in plants. Accumulating evidence suggests that the nuclear pools of antioxidants such as glutathione are discrete and separate from the cytosolic pools, allowing compartment-specific signalling in the nucleus. We consider the potential mechanisms of superoxide generation and targets in the nucleus, together with the importance of antioxidant processing in regulating superoxide signalling.

Nicotinamide adenine dinucleotide phosphate oxidase 2 deletion attenuates polyhexamethylene guanidine-induced lung injury in mice.

Inhalation of polyhexamethylene guanidine phosphate (PHMG) can cause pulmonary fibrosis. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (Nox) are enzymes that produce reactive oxygen species, which may be involved in tissue damage in various lung diseases. To investigate whether the Nox2 isoform of Nox is involved in the progression of PHMG-induced lung damage, we studied the contribution of Nox2 in PHMG-induced lung injury in Nox2-deficient mice. We treated wild-type (WT) and Nox2 knockout mice with a single intratracheal instillation of 1.1 mg/kg PHMG and sacrificed them after 14 days. We analyzed lung histopathology and the number of total and differential cells in the bronchoalveolar lavage fluid. In addition, the expressions of cytokines, chemokines, and profibrogenic genes were analyzed in the lung tissues. Based on our results, Nox2-deficient mice showed less PHMG-induced pulmonary damage than WT mice, as indicated by parameters such as body weight, lung weight, total cell count, cytokine and chemokine levels, fibrogenic mediator expression, and histopathological findings. These findings suggest that Nox2 may have the potential to contribute to PHMG-induced lung injury and serves as an essential signaling molecule in the development of PHMG-induced pulmonary fibrosis by regulating the expression of profibrogenic genes.

Role of the CCL5 and Its Receptor, CCR5, in the Genesis of Aldosterone-Induced Hypertension, Vascular Dysfunction, and End-Organ Damage.

BACKGROUND: Aldosterone has been described to initiate cardiovascular diseases by triggering exacerbated sterile vascular inflammation. The functions of CCL5 (C-C motif chemokine ligand 5) and its receptor CCR5 (C-C motif chemokine receptor 5) are well known in infectious diseases, their contributions to aldosterone-induced vascular injury and hypertension remain unknown. METHODS: We analyzed the vascular profile, blood pressure, and renal damage in wild-type (CCR5+/+) and CCR5 knockout (CCR5-/-) mice treated with aldosterone (600 µg/kg per day for 14 days) while receiving 1% saline to drink. Vascular function was analyzed in aorta and mesenteric arteries, blood pressure was measured by telemetry and renal injury and inflammation were analyzed via histology and flow cytometry. Endothelial cells were used to study the molecular signaling whereby CCL5 induces endothelial dysfunction. RESULTS: Aldosterone treatment resulted in exaggerated CCL5 circulating levels and vascular CCR5 expression in CCR5+/+ mice accompanied by endothelial dysfunction, hypertension, and renal inflammation and damage. CCR5-/- mice were protected from these aldosterone-induced effects. Mechanistically, we demonstrated that CCL5 increased NOX1 (NADPH oxidase 1) expression, reactive oxygen species formation, NFκB (nuclear factor kappa B) activation, and inflammation and reduced NO production in isolated endothelial cells. These effects were abolished by antagonizing CCR5 with Maraviroc. Finally, aorta incubated with CCL5 displayed severe endothelial dysfunction, which is prevented by blocking NOX1, NFκB, or CCR5. CONCLUSIONS: Our data demonstrate that CCL5/CCR5, through activation of NFκB and NOX1, is critically involved in aldosterone-induced vascular and renal damage and hypertension placing CCL5 and CCR5 as potential therapeutic targets for conditions characterized by aldosterone excess.

Vascular Inflammation and Smooth Muscle Contractility: The Role of Nox1-Derived Superoxide and LRRC8 Anion Channels.

Vascular inflammation underlies the development of hypertension, and the mechanisms by which it increases blood pressure remain the topic of intense investigation. Proinflammatory factors including glucose, salt, vasoconstrictors, cytokines, wall stress, and growth factors enhance contractility and impair relaxation of vascular smooth muscle cells. These pathways share a dependence upon redox signaling, and excessive activation promotes oxidative stress that promotes vascular aging. Vascular smooth muscle cell phenotypic switching and migration into the intima contribute to atherosclerosis, while hypercontractility increases systemic vascular resistance and vasospasm that can trigger ischemia. Here, we review factors that drive the initiation and progression of this vasculopathy in vascular smooth muscle cells. Emphasis is placed on the contribution of reactive oxygen species generated by the Nox1 NADPH oxidase which produces extracellular superoxide (O2•-). The mechanisms of O2•- signaling remain poorly defined, but recent evidence demonstrates physical association of Nox1 with leucine-rich repeat containing 8 family volume-sensitive anion channels. These may provide a pathway for influx of O2•- to the cytoplasm, creating an oxidized cytoplasmic nanodomain where redox-based signals can affect both cytoskeletal structure and vasomotor function. Understanding the mechanistic links between inflammation, O2•- and vascular smooth muscle cell contractility may facilitate targeting of anti-inflammatory therapy in hypertension.

Pulmonary Hypertension Induces Serotonin Hyperreactivity and Metabolic Reprogramming in Coronary Arteries via NOX1/4-TRPM2 Signaling Pathway.

BACKGROUND: Clinical evidence revealed abnormal prevalence of coronary artery (CA) disease in patients with pulmonary hypertension (PH). The mechanistic connection between PH and CA disease is unclear. Serotonin (5-hydroxytryptamine), reactive oxygen species, and Ca2+ signaling have been implicated in both PH and CA disease. Our recent study indicates that NOXs (NADPH [nicotinamide adenine dinucleotide phosphate] oxidases) and TRPM2 (transient receptor potential cation channel subfamily M member 2) are key components of their interplay. We hypothesize that activation of the NOX-TRPM2 pathway facilitates the remodeling of CA in PH. METHODS: Left and right CAs from chronic hypoxia and monocrotaline-induced PH rats were collected to study vascular reactivity, gene expression, metabolism, and mitochondrial function. Inhibitors or specific siRNA were used to examine the pathological functions of NOX1/4-TRPM2 in CA smooth muscle cells. RESULTS: Significant CA remodeling and 5-hydroxytryptamine hyperreactivity in the right CA were observed in PH rats. NOX1/4-mediated reactive oxygen species production coupled with TRPM2-mediated Ca2+ influx contributed to 5-hydroxytryptamine hyperresponsiveness. CA smooth muscle cells from chronic hypoxia-PH rats exhibited increased proliferation, migration, apoptosis, and metabolic reprogramming in an NOX1/4-TRPM2-dependent manner. Furthermore, the NOX1/4-TRPM2 pathway participated in mitochondrial dysfunction, involving mitochondrial DNA damage, reactive oxygen species production, elevated mitochondrial membrane potential, mitochondrial Ca2+ accumulation, and mitochondrial fission. In vivo knockdown of NOX1/4 alleviated PH and suppressed CA remodeling in chronic hypoxia rats. CONCLUSIONS: PH triggers an increase in 5-hydroxytryptamine reactivity in the right CA and provokes metabolic reprogramming and mitochondrial disruption in CA smooth muscle cells via NOX1/4-TRPM2 activation. This signaling pathway may play an important role in CA remodeling and CA disease in PH.

ROS produced by NOX promote the neurite growth in a PI3K/Akt independent manner.

Reactive oxygen species (ROS) function as signaling molecules in several physiologic and pathologic processes. In central nervous system, ROS are critical for differentiation, migration, polarization, and neurite growth. These actions are mediated by reversible oxidation of target proteins. On the other hand, PI3K/Akt signaling pathway is susceptible to be modulated by ROS and it has been implicated in neurite growth. In this study, we evaluated the participation of ROS in the neurite growth of cultured rat cerebellar granule neurons (CGN), as well as the possible regulation of the PI3K/Akt pathway by ROS during neurite outgrowth. For this purpose, CGN were treated with cellular or mitochondrial antioxidants, or an NOX inhibitor and neurite growth was evaluated. Moreover, to assess the participation Akt in this process, the p-Akt levels were measured in CGN treated with antioxidants or a NOX inhibitor. The effect of antioxidants on the neurite growth in the presence of a PI3K inhibitor was also measured. We found that cellular antioxidants and the NOX inhibitor decreased the neurite growth, but not the mitochondrial antioxidant. Interestingly, the antioxidants increased the p-Akt levels; however, the effect of antioxidants on neurite growth was no dependent on the Akt activity since the inhibitor of PI3K did not modify the antioxidant action on neurite growth. Our results show that the PI3K/Akt pathway participates in neurite growth and that ROS produced by NOX could function as signals in this process; however, this action is not mediated by a redox regulation of Akt activity.

Obstructive sleep apnea: Beyond the dogma of obesity!

Obstructive sleep apnea (OSA) has long been studied in patients with obesity and type 2 diabetes mellitus (T2DM), due to the fact that both disorders are commonly associated with an increased body mass index (BMI). However, a link between OSA and non-obese diabetic patients is still not very elaborated, nor heavily explored. In this review, we elucidate some proposed mechanisms for the link between OSA and diabetic patients both with and beyond obesity, shedding the light on the latter case. One such mechanism is oxidative stress, a phenomenon of reactive oxygen species (ROS) imbalance seen in both of the previously mentioned disorders. A plausible explanation for the OSA-induced ROS production is the repeating episodes of hypoxia and reperfusion and their effect on the mitochondrial electron transport chain. This paper explores the literature regarding ROS imbalance as the possible missing link between OSA and Diabetes Mellitus beyond obesity, while still mentioning other possible proposed mechanisms such as a dysregulated autonomic nervous system (ANS), as well as mechanical and craniofacial abnormalities. This paper also suggests a link between OSA and diabetic complications, while exploring the clinical progress made in treating the former disorder with anti-oxidant and hypo-glycemic drugs. If further investigated, these findings could help identify novel therapeutic interventions for the treatment of OSA and Diabetic patients.

Targeting of the NOX1/ADAM17 Enzymatic Complex Regulates Soluble MCAM-Dependent Pro-Tumorigenic Activity in Colorectal Cancer.

The melanoma cell adhesion molecule, shed from endothelial and cancer cells, is a soluble growth factor that induces tumor angiogenesis and growth. However, the molecular mechanism accounting for its generation in a tumor context is still unclear. To investigate this mechanism, we performed in vitro experiments with endothelial/cancer cells, gene expression analyses on datasets from human colorectal tumor samples, and applied pharmacological methods in vitro/in vivo with mouse and human colorectal cancer cells. We found that soluble MCAM generation is governed by ADAM17 proteolytic activity and NOX1-regulating ADAM17 expression. The treatment of colorectal tumor-bearing mice with pharmacologic NOX1 inhibitors or tumor growth in NOX1-deficient mice reduced the blood concentration of soluble MCAM and abrogated the anti-tumor effects of anti-soluble MCAM antibodies while ADAM17 pharmacologic inhibitors reduced tumor growth and angiogenesis in vivo. Especially, the expression of MCAM, NOX1, and ADAM17 was more prominent in the angiogenic, colorectal cancer-consensus molecular subtype 4 where high MCAM expression correlated with angiogenic and lymphangiogenic markers. Finally, we demonstrated that soluble MCAM also acts as a lymphangiogenic factor in vitro. These results identify a role for NOX1/ADAM17 in soluble MCAM generation, with potential clinical therapeutic relevance to the aggressive, angiogenic CMS4 colorectal cancer subtype.

Role Of The C-C Motif Chemokine Ligand 5 (CCL5) And Its Receptor, C-C Motif Chemokine Receptor 5 (CCR5) In The Genesis Of Aldosterone-induced Hypertension, Vascular Dysfunction, And End-organ Damage.

Background: Aldosterone, a mineralocorticoid steroid hormone, has been described to initiate cardiovascular diseases by triggering exacerbated sterile vascular inflammation. The functions of C-C Motif Chemokine Ligand 5 (CCL5) and its receptor, C-C Motif Chemokine Receptor 5 (CCR5), are well known in infectious diseases, but their roles in the genesis of aldosterone-induced vascular injury and hypertension are unknown. Methods: We analyzed the vascular profile, blood pressure, and renal damage in wild-type (CCR5+/+) and CCR5 knockout (CCR5-/-) mice treated with aldosterone (600 µg/kg/day for 14 days) while receiving 1% saline to drink. Results: Here, we show that CCR5 plays a central role in aldosterone-induced vascular injury, hypertension, and renal damage. Long-term infusion of aldosterone in CCR5+/+ mice resulted in exaggerated CCL5 circulating levels and vascular CCR5 expression. Aldosterone treatment also triggered vascular injury, characterized by endothelial dysfunction and inflammation, hypertension, and renal damage. Mice lacking CCR5 were protected from aldosterone-induced vascular damage, hypertension, and renal injury. Mechanistically, we demonstrated that CCL5 increased NADPH oxidase 1 (Nox1) expression, reactive oxygen species (ROS) formation, NFκB activation, and inflammation and reduced nitric oxide production in isolated endothelial cells. These effects were abolished by antagonizing CCR5 with Maraviroc. Finally, aortae incubated with CCL5 displayed severe endothelial dysfunction, which is prevented by blocking Nox1, NFκB, or with Maraviroc treatment. Conclusions: Our data demonstrate that CCL5/CCR5, through activation of NFkB and Nox1, is critically involved in aldosterone-induced vascular and renal damage and hypertension. Our data place CCL5 and CCR5 as potential targets for therapeutic interventions in conditions with aldosterone excess.

NADPH Oxidases and Oxidative Stress in the Pathogenesis of Atrial Fibrillation.

Atrial fibrillation (AF) is the most common type of cardiac arrhythmia and its prevalence increases with age. The irregular and rapid contraction of the atria can lead to ineffective blood pumping, local blood stasis, blood clots, ischemic stroke, and heart failure. NADPH oxidases (NOX) and mitochondria are the main sources of reactive oxygen species in the heart, and dysregulated activation of NOX and mitochondrial dysfunction are associated with AF pathogenesis. NOX- and mitochondria-derived oxidative stress contribute to the onset of paroxysmal AF by inducing electrophysiological changes in atrial myocytes and structural remodeling in the atria. Because high atrial activity causes cardiac myocytes to expend extremely high energy to maintain excitation-contraction coupling during persistent AF, mitochondria, the primary energy source, undergo metabolic stress, affecting their morphology, Ca2+ handling, and ATP generation. In this review, we discuss the role of oxidative stress in activating AF-triggered activities, regulating intracellular Ca2+ handling, and functional and anatomical reentry mechanisms, all of which are associated with AF initiation, perpetuation, and progression. Changes in the extracellular matrix, inflammation, ion channel expression and function, myofibril structure, and mitochondrial function occur during the early transitional stages of AF, opening a window of opportunity to target NOX and mitochondria-derived oxidative stress using isoform-specific NOX inhibitors and mitochondrial ROS scavengers, as well as drugs that improve mitochondrial dynamics and metabolism to treat persistent AF and its transition to permanent AF.

Doença granulomatosa crônica: características clínicas, seguimento e terapêutica de cinco pacientes pediátricos / Chronic granulomatous disease: clinical characteristics, follow-up, and therapy of 5 pediatric patients

Introdução: A doença granulomatosa crônica (DGC) é caracterizada por um defeito na capacidade microbicida das células fagocíticas (monócitos e neutrófilos), com alta mortalidade se não diagnosticada precocemente. Os pacientes apresentam infecções recorrentes ou graves, suscetibilidade a granulomas em órgãos profundos, doenças autoimunes e doença inflamatória intestinal. Objetivo e Método: Relato de aspectos clínicos e do tratamento de cinco pacientes com doença granulomatosa crônica. Resultados: Cinco pacientes, três meninos, medianas de idade no início dos sintomas e diagnóstico de 8 meses e 48 meses, respectivamente, foram estudados por um período de 10 anos. Pneumonia (5/5) e doença micobacteriana (3/5) foram as manifestações iniciais mais comuns. Alterações pulmonares foram observadas em todos os casos. Mutações nos genes CYBB e NCF1 foram identificadas em três casos. Antibioticoprofilaxia foi instituída em todos os pacientes e três foram submetidos ao transplante de células tronco-hematopoiéticas (TCH), aos 7, 18 e 19 anos e com sobrevida atual entre 4 a 5 anos. Conclusão: O monitoramento cuidadoso de infecções graves com tratamento imediato foi crucial para a sobrevivência. O TCH, mesmo ao final da adolescência, promoveu a cura da DGC em três pacientes.

Introduction: Chronic granulomatous disease (CGD) is characterized by a defective microbicidal capacity of phagocytic cells (monocytes and neutrophils) with high mortality if not early diagnosed. Patients have recurrent or severe infections and are susceptible to granulomas in visceral organs, autoimmune diseases, and inflammatory bowel diseases. Objective and Method: To report the clinical features and treatment of 5 patients with CGD. Results: Five patients, 3 boys, with median ages at symptom onset and diagnosis of 8 months and 48 months, respectively, were followed for 10 years. Pneumonia (5/5) and mycobacterial disease (3/5) were the most common initial manifestations. Pulmonary changes were observed in all cases. Mutations in the CYBB and NCF1 genes were identified in 3 cases. All patients received antibiotic prophylaxis. Three patients underwent a hematopoietic stem cell transplant (HSCT) at 7, 18, and 19 years, with current survival of 4 to 5 years. Conclusion: Careful monitoring for severe infection with prompt treatment was crucial for survival. Even though HSCT was performed in late adolescence, it promoted the cure of CGD in 3 patients.

Galectin-3 Mediates Vascular Dysfunction in Obesity by Regulating NADPH Oxidase 1.

BACKGROUND: Obesity is associated with increased risk of cardiovascular disease, but underlying mechanisms remain elusive. Metabolic dysfunction, especially hyperglycemia, is thought to be a major contributor, but how glucose impacts vascular function is unclear. GAL3 (galectin-3) is a sugar-binding lectin upregulated by hyperglycemia, but its role as a causative mechanism of cardiovascular disease remains poorly understood. Therefore, the objective of this study was to determine the role of GAL3 in regulating microvascular endothelial vasodilation in obesity. METHODS: GAL3 was measured and found to be markedly increased in the plasma of overweight and obese patients, as well as in the microvascular endothelium of diabetic patients. To investigate causative mechanisms in cardiovascular disease, mice deficient in GAL3 were bred with obese db/db mice to generate lean, lean GAL3 knockout, obese, and obese GAL3 knockout genotypes. Endothelial cell-specific GAL3 knockout mice with novel AAV-induced obesity recapitulated whole-body knockout studies to confirm cell specificity. RESULTS: Deletion of GAL3 did not alter body mass, adiposity, or plasma indices of glycemia and lipidemia, but levels of plasma reactive oxygen species as assessed by plasma thiobarbituric acid reactive substances were normalized in obese GAL3 knockout mice. Obese mice exhibited profound endothelial dysfunction and hypertension, both of which were rescued by GAL3 deletion. Isolated microvascular endothelial cells from obese mice had increased expression of NOX1 (nicotinamide adenine dinucleotide phosphate oxidase 1), which we have previously shown to contribute to increased oxidative stress and endothelial dysfunction, which was normalized in microvascular endothelium from mice lacking GAL3. Cell-specific deletion confirmed that endothelial GAL3 regulates obesity-induced NOX1 overexpression and subsequent microvascular function. Furthermore, improvement of metabolic syndrome by increasing muscle mass, improving insulin signaling, or treating with metformin decreased microvascular GAL3, and thereby NOX1, expression levels. CONCLUSIONS: Deletion of GAL3 normalizes microvascular endothelial function in obese db/db mice, likely through a NOX1-mediated mechanism. Pathological levels of GAL3, and in turn NOX1, are amenable to improvements in metabolic status, presenting a potential therapeutic target to ameliorate pathological cardiovascular consequences of obesity.

Involvement of NADPH oxidases in the Na/K­ATPase/Src/ROS oxidant amplification loop in renal fibrosis.

The Na/K­ATPase/Src complex is reportedly able to affect reactive oxygen species (ROS) amplification. However, it has remained elusive whether NADPH oxidases (NOXs) are involved in this oxidant amplification loop in renal fibrosis. To test this hypothesis, interactions between oxidative features and Na/K­ATPase/Src activation were examined in a mouse model of unilateral urethral obstruction (UUO)­induced experimental renal fibrosis. Both 1­tert­butyl­3­(4­chlorophenyl)­1H­pyrazolo[3,4­d]pyrimidin­4­amine (PP2) and apocynin significantly attenuated the development of UUO­induced renal fibrosis. Apocynin administration attenuated the expression of NOXs and oxidative markers (e.g., nuclear factor erythroid 2­related factor 2, heme oxygenase­1,4­hydroxynonenal and 3­nitrotyrosine); it also partially restored Na/K­ATPase expression and inhibited the activation of the Src/ERK cascade. Furthermore, administration of PP2 after UUO induction partially reversed the upregulation of NOX2, NOX4 and oxidative markers, while inhibiting the activation of the Src/ERK cascade. Complementary experiments in LLC­PK1 cells corroborated the in vivo observations. Inhibition of NOX2 by RNA interference attenuated ouabain­induced oxidative stress, ERK activation and E­cadherin downregulation. Thus, it is indicated that NOXs are major contributors to ROS production in the Na/K­ATPase/Src/ROS oxidative amplification loop, which is involved in renal fibrosis. The disruption of this vicious feed­forward loop between NOXs/ROS and redox­regulated Na/K­ATPase/Src may have therapeutic applicability for renal fibrosis disorders.

Ang II Promotes ET-1 Production by Regulating NOX2 Activity Through Transcription Factor Oct-1.

BACKGROUND: Increasing evidence suggests that superoxide ions produced by NOX (nicotinamide adenine dinucleotide phosphate oxidases) mediate vascular effects of Ang II (angiotensin II) evoked by atherogenic diets. Here, we analyzed the mechanism by which NOX2 contributes to Ang II-induced ET-1 (endothelin 1) production in human microvascular endothelial cells. METHODS: The effects of high-fat diet were compared between WT (wild type) and Nox2 (mouse NOX2 gene)-deficient mice. ET-1 production and NOX2 expression by human microvascular endothelial cells in vitro were analyzed by ELISA, reverse transcription quantitative polymerase chain reaction, electrophoretic mobility shift assay, promoter deletions, RNA interference, and pharmacological inhibition. Production of superoxide anions was visualized by fluorescent cell labeling. RESULTS: Feeding mice high-fat diet for 10 weeks increased cardiac expression and plasma levels of Ang II and ET-1 in WT but not in Nox2-deficient animals. Exposure of human microvascular endothelial cells to Ang II resulted in increased ET-1 production, which could be blocked by silencing NOX2 (human NOX2 gene). Ang II promoted NOX2 expression through induction of the Oct-1 (human/mouse octamer binding transcription factor 1 protein) and activation of the NOX2 promoter region containing Oct-1-binding sites. Stimulation of NOX2 expression by Ang II was associated with increased production of superoxide anions. Inhibition of Oct-1 by small interfering RNA reduced Ang II-induced NOX2 expression and superoxide anion production, and neutralization of superoxide by SOD (superoxide dismutase) abolished Ang II-stimulated ET1 (human ET-1 gene) promoter activity, ET1 mRNA expression, and ET-1 release. CONCLUSIONS: Ang II may promote ET-1 production in the endothelium in response to atherogenic diets through a mechanism that involves the transcription factor Oct-1 and the increased formation of superoxide anions by NOX2.