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1.
Apoptosis ; 29(3-4): 321-330, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37796354

ABSTRACT

The removal of dead cells (efferocytosis) contributes to the resolution of the infection and preservation of the tissue. Depending on the environment milieu, macrophages may show inflammatory (M1) or anti-inflammatory (M2) phenotypes. Inflammatory leukocytes are recruited during infection, followed by the accumulation of infected and non-infected apoptotic cells (AC). Efferocytosis of non-infected AC promotes TGF-ß, IL-10, and PGE2 production and the polarization of anti-inflammatory macrophages. These M2 macrophages acquire an efficient ability to remove apoptotic cells that are involved in tissue repair and resolution of inflammation. On the other hand, the impact of efferocytosis of infected apoptotic cells on macrophage activation profile remains unknown. Here, we are showing that the efferocytosis of gram-positive Streptococcus pneumoniae-AC (Sp-AC) or gram-negative Klebsiella pneumoniae-AC (Kp-AC) promotes distinct gene expression and cytokine signature in macrophages. Whereas the efferocytosis of Kp-AC triggered a predominant M1 phenotype in vitro and in vivo, the efferocytosis of Sp-AC promoted a mixed M1/M2 activation in vitro and in vivo in a model of allergic asthma. Together, these findings suggest that the nature of the pathogen and antigen load into AC may have different impacts on inducing macrophage polarization.


Subject(s)
Apoptosis , Phagocytosis , Macrophages/metabolism , Phenotype , Anti-Inflammatory Agents
2.
Int J Mol Sci ; 24(13)2023 Jun 21.
Article in English | MEDLINE | ID: mdl-37445595

ABSTRACT

There is evidence that IL-22 and IL-17 participate in the pathogenesis of allergic asthma. To investigate the role of IL-22, we used IL-22 deficient mice (IL-22 KO) sensitized and challenged with ovalbumin (OVA) and compared with wild type (WT) animals exposed to OVA. IL-22 KO animals exposed to OVA showed a decreased number and frequency of eosinophils, IL-5 and IL-13 in the airways, reduced mucus production and pulmonary inflammation. In addition, IL-22 KO animals exhibited a decreased percentage and number of lung CD11c+CD11b+ cells and increased apoptosis of eosinophils. Th17 cell transfer generated from IL-22 KO to animals previously sensitized and challenged with OVA caused a reduction in eosinophil frequency and number in the airways compared to animals transferred with Th17 cells generated from WT mice. Therefore, IL-22 is deleterious with concomitant secretion of IL-17. Our findings show a pro-inflammatory role for IL-22, confirmed in a model of allergen-free and allergen-specific immunotherapy. Moreover, during the comorbidity asthma and pneumonia that induces neutrophil inflammation, IL-22 was not detrimental. Our results show that targeting IL-22 would negatively affect the survival of eosinophils, reduce the expansion or migration of CD11c+CD11b+ cells, and negatively regulate allergic asthma.


Subject(s)
Asthma , Pneumonia , Mice , Animals , Interleukin-17/genetics , Asthma/pathology , Lung/pathology , Eosinophils , Pneumonia/pathology , Allergens , Comorbidity , Ovalbumin , Disease Models, Animal , Bronchoalveolar Lavage Fluid , Mice, Inbred BALB C
3.
Allergol Immunopathol (Madr) ; 50(2): 115-123, 2022.
Article in English | MEDLINE | ID: mdl-35257554

ABSTRACT

OBJECTIVE: To evaluate the effect of a hydroethanolic extract of Momordica charantia L. ("bitter melon", Cucurbitaceae) leaves (MCHA) on ovalbumin (OVA)-induced asthma model. Balb/c mice were sensitized twice and challenged for 4 alternate days with OVA and then treated with MCHA (500 mg/kg) for 7 consecutive days. METHODS: Control groups received treatment with normal saline or dexamethasone (2 mg/kg) on the same day. We assessed in vivo bronchial hyperresponsiveness and ex-vivo inflammation and mucus production in bronchoalveolar lavage (BAL), lung homogenates, and lung tissue. RESULTS: MCHA significantly improved airway hyperresponsiveness near baseline levels. MCHA administration significantly improved airway and lung inflammation, demonstrated by decreased total and inflammatory cells in BAL, lower levels of IL-5 and IL-13 in lung homogenate, and fewer inflammatory cells in lung tissue. Additionally, MCHA significantly diminished goblet cells in lung tissue. CONCLUSIONS: Administration of a hydroethanolic extract of M. charantia leaves was effective in treating OVA-induced asthma in an animal model.


Subject(s)
Asthma , Bronchial Hyperreactivity , Momordica charantia , Animals , Asthma/drug therapy , Bronchial Hyperreactivity/drug therapy , Bronchoalveolar Lavage Fluid , Cytokines , Disease Models, Animal , Humans , Inflammation/drug therapy , Lung , Mice , Mice, Inbred BALB C , Ovalbumin
4.
Dig Dis Sci ; 66(8): 2610-2618, 2021 08.
Article in English | MEDLINE | ID: mdl-32839905

ABSTRACT

BACKGROUND: Since HLA-G is an immune checkpoint molecule and since Crohn's disease (CD) and ulcerative colitis (UC) exhibit deregulated immune-mediated mechanisms, we aimed to evaluate intestinal HLA-G expression and soluble HLA-G (sHLA-G) levels in CD/UC patients stratified according to the CD phenotype/localization and UC extension. METHODS: HLA-G tissue expression was assessed by immunohistochemistry in biopsies collected from 151 patients (90 CD, 61 UC) and in surgical resection specimens (28 CD, 12 UC). Surgical material from 24 healthy controls was also assessed. Plasma sHLA-G levels (97 CD, 81 UC, and 120 controls) were evaluated using ELISA. RESULTS: HLA-G expression was similarly observed in the intestinal epithelial cells of control and CD/UC specimens. However, in biopsies, the plasma cells/lymphocytes infiltrating the lamina propria in CD/UC presented (1) increased HLA-G expression compared to controls (P < 0.0001), (2) greater cell staining in UC cells than in CD cells irrespective of disease extent (P = 0.0011), and (3) an increased number of infiltrating cells in the inflammatory CD phenotype compared to that in the stenosing and fistulizing phenotypes (P = 0.0407). In surgical specimens, CD/UC patients exhibited higher infiltrating cell HLA-G expression in lesion areas than in margins. sHLA-G levels were higher in UC/CD patients (P < 0.0001) than in controls, but no difference was observed between diseases. CONCLUSIONS: Increased infiltrating cell HLA-G expression associated with increased sHLA-G levels in CD/UC patients may reflect ongoing host strategies to suppress chronic inflammation.


Subject(s)
Colitis, Ulcerative/pathology , Crohn Disease/pathology , Gene Expression Regulation/immunology , HLA-G Antigens/metabolism , Adolescent , Adult , Female , HLA-G Antigens/genetics , Humans , Inflammation , Intestinal Mucosa/pathology , Male , Middle Aged , Young Adult
5.
Molecules ; 26(23)2021 Dec 02.
Article in English | MEDLINE | ID: mdl-34885894

ABSTRACT

Aflatoxins are mycotoxins produced as secondary fungal metabolites. Among them, aflatoxin B1 (AFB1) stands out due to its genotoxic and mutagenic potential, being a potent initiator of carcinogenesis. In this review, the outcomes from the published literature in the past 10 years on the effects of AFB1 pathophysiological mechanisms on embryological and fetal development are discussed. In several animal species, including humans, AFB1 has a teratogenic effect, resulting in bone malformations, visceral anomalies, lesions in several organs, and behavioral and reproductive changes, in addition to low birth weight. The mutagenic capacity of AFB1 in prenatal life is greater than in adults, indicating that when exposure occurs in the womb, the risk of the development of neoplasms is higher. Studies conducted in humans indicate that the exposure to this mycotoxin during pregnancy is associated with low birth weight, decreased head circumference, and DNA hypermethylation. However, as the actual impacts on humans are still unclear, the importance of this issue cannot be overemphasized and studies on the matter are essential.


Subject(s)
Aflatoxin B1/toxicity , Mutagens/toxicity , Prenatal Exposure Delayed Effects/chemically induced , Animals , DNA Methylation/drug effects , Female , Humans , Neoplasms/chemically induced , Neoplasms/genetics , Neoplasms/pathology , Pregnancy , Prenatal Exposure Delayed Effects/genetics , Prenatal Exposure Delayed Effects/pathology
6.
Clin Immunol ; 217: 108482, 2020 08.
Article in English | MEDLINE | ID: mdl-32470543

ABSTRACT

Chronic hepatitis C virus (HCV) infection induces liver damage and the HCV/Human Immunodeficiency Virus (HIV)-coinfection may further contribute to its progression. The HLA-G molecule inhibits innate and adaptive immunity and may be deleterious for chronically virus-infected cells. Thus we studied 204 HCV-mono-infected patients, 142 HCV/HIV-coinfected patients, 104 HIV-mono-infected patients and 163 healthy subjects. HLA-G liver expression was similarly induced in HCV and HCV/HIV specimens, increasing with advanced fibrosis and necroinflammatory activity, and with increased levels of liver function-related enzymes. Plasma soluble HLA-G (sHLA-G) levels were higher in HCV/HIV patients compared to HCV, HIV and to healthy individuals. sHLA-G continued to be higher in coinfected patients even after stratification of samples according to degree of liver fibrosis and necroinflammatory activity when compared to mono-infected patients. Some HLA-G gene haplotypes differentiated patient groups and presented few associations with liver and plasma HLA-G expression. HLA-G thus may help to distinguish patient groups.


Subject(s)
HIV Infections/immunology , HLA-G Antigens/genetics , HLA-G Antigens/metabolism , Hepatitis C, Chronic/immunology , Liver/metabolism , Adult , Coinfection , Female , Gene Expression Regulation/genetics , Gene Expression Regulation/immunology , HIV-1/immunology , Haplotypes/genetics , Hepacivirus/immunology , Humans , Male , Middle Aged , Polymorphism, Genetic/genetics , Retrospective Studies
7.
Eur J Nutr ; 59(1): 93-102, 2020 Feb.
Article in English | MEDLINE | ID: mdl-30604178

ABSTRACT

PURPOSE: This experimental study investigated the effects of curcuma supplementation on weight gain, Body Adiposity Index, glucose and lipid profile, and liver and pancreas histology in C57BL/6 mice fed with a high-fat diet. METHODS: 40 animals were separated into four groups: standard diet (SD), standard diet plus curcuma (SD + C), high-fat diet (HFD), and high-fat diet plus curcuma (HFD + C). Curcuma dose was 8 mg/animal/day. Histological and biochemical analyses were performed at the end of the experimental period. RESULTS: Curcuma prevented weight gain, despite a higher food intake, and increased brown adipose tissue weight only in mice receiving standard diet. However, these changes were not observed in HFD + C group. The groups that received curcuma (SD + C and HFD + C) showed a pancreas with diffuse macro- and microgoticular steatosis. CONCLUSIONS: Curcuma supplementation did not prevent weight gain or improved glucose and lipid profile in mice receiving high-fat diet. Furthermore, there was evidence of possible curcuma toxicity in the pancreas of C57BL/6 mice. The implications of these findings on humans still need to be investigated.


Subject(s)
Curcuma/metabolism , Diet, High-Fat/methods , Dietary Supplements , Glucose/metabolism , Lipid Metabolism/drug effects , Weight Gain/drug effects , Animals , Male , Mice , Mice, Inbred C57BL , Models, Animal
8.
Arch Toxicol ; 93(7): 1955-1964, 2019 07.
Article in English | MEDLINE | ID: mdl-31020376

ABSTRACT

Acetaminophen (APAP) is one of the most widely consumed drugs in the world. Studies have shown renal and hepatic damage as the direct result of high oxidative stress induced by APAP. Since the cardiovascular system is sensitive to oxidative stress and literature describes increased cardiovascular dysfunction in APAP consumers, this work aimed to evaluate harmful effects of APAP on the vascular system. Rats were exposed to APAP (400 mg/kg/day in drinking water) for 14 days. Plasma and aortas were collected and stored in - 80 °C and a selection of arteries was prepared for isometric tension recordings, morphological, immunohistochemical and protein expression analysis. The APAP-treated group presented increased transaminases (ALT/AST) and malondialdehyde levels in the plasma compared to controls. Lipid peroxidation, glutathione reductase and superoxide dismutase levels were increased in the plasma and arteries of the APAP group. Nevertheless, glutathione level was reduced as compared to control group. The vasodilation response to acetylcholine and sodium nitroprusside (0.1 nM to 10 µM) was also impaired after APAP treatment; however, the vascular relaxation was restored after treatment with vitamin C (100 µM). Arteries from the APAP group presented reduced wall thickness, collagen deposition, elastic fibers and increased immunoreactivity to nitrotyrosine. eNOS and sGC protein expression remained unchanged and were at similar levels as controls. These findings showed higher oxidative stress and impaired vasodilation in rats exposed to APAP. Furthermore, arteries presented reduced cell layers, collagen, elastin deposition and significantly increased immunoreactivity to nitrotyrosine after APAP treatment.


Subject(s)
Acetaminophen/toxicity , Aorta, Thoracic/drug effects , Drug-Related Side Effects and Adverse Reactions , Oxidative Stress/drug effects , Vasodilation/drug effects , Animals , Antioxidants/metabolism , Aorta, Thoracic/metabolism , Aorta, Thoracic/pathology , Drug-Related Side Effects and Adverse Reactions/metabolism , Drug-Related Side Effects and Adverse Reactions/pathology , Endothelium, Vascular/drug effects , Lipid Peroxidation/drug effects , Liver/drug effects , Liver/enzymology , Male , Rats , Rats, Wistar
9.
Childs Nerv Syst ; 35(4): 689-694, 2019 04.
Article in English | MEDLINE | ID: mdl-30631904

ABSTRACT

BACKGROUND: Ependymoma (EPN) is the third most common central nervous system tumor in childhood. Recent advances in the molecular classification of EPN revealed a supratentorial (ST) ependymoma subgroup characterized by C11orf95-RELA fusion. CASE REPORT: We describe a novel RELA-fusion composed by a chimeric transcript C11orf95-LOC-RELA in a supratentorial WHO grade II EPN occurring in a 4-year-old child. Metastatic loci at the brain, leptomeningeal involvement, and pulmonary nodules were identified at tumor recurrence. The child eventually died before 1 year after recurrence. CONCLUSION: This index case showed aggressive behavior and nuclear accumulation of p65/RELA.


Subject(s)
Ependymoma/genetics , Oncogene Proteins, Fusion/genetics , Proteins/genetics , Supratentorial Neoplasms/genetics , Transcription Factor RelA/genetics , Child, Preschool , Ependymoma/pathology , Humans , Male , Supratentorial Neoplasms/pathology
10.
BMC Urol ; 18(1): 50, 2018 May 29.
Article in English | MEDLINE | ID: mdl-29843769

ABSTRACT

BACKGROUND: The objectives of this study were to determine the minimum incidence of penile cancer in the poorest Brazilian state, and to describe the epidemiologic and clinical characteristics of patients diagnosed with the disease. METHODS: A retrospective study of 392 patients diagnosed with penile cancer in the three most important referral center in the state was conducted during 2004-2014. RESULTS: The age-standardized incidence was 6.15 per 100,000 and the crude annual incidence was 1.18 per 100,000. More than half (61.1%) of the tumors were histological grades 2 and 3, and 66.4% of tumors were classified as at least stage T2. The average age of patients was 58.6 ± 15.7 years (range, 18 to 103 years), with 20.8% of patients ≤40 years of age at diagnosis. The vast majority underwent penectomy (93%). Only 41.8% underwent lymphadenectomy, 58 patients (14.8%) received chemotherapy, and 54 patients (13.8%) received radiotherapy. Stage 3/4 and vascular invasion were statically significant at disease-free survival analysis. CONCLUSION: The state of Maranhão has the highest incidence of penile cancer in Brazil and globally. Tumors are locally advanced and at the time of diagnosis, and there is a high frequency among young individuals. Patients have a low socioeconomic status, making it difficult to complete treatment and receive appropriate follow-up.


Subject(s)
Carcinoma, Squamous Cell/diagnosis , Carcinoma, Squamous Cell/epidemiology , Global Health , Penile Neoplasms/diagnosis , Penile Neoplasms/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , Brazil/epidemiology , Carcinoma, Squamous Cell/surgery , Disease-Free Survival , Follow-Up Studies , Humans , Incidence , Male , Middle Aged , Penile Neoplasms/surgery , Retrospective Studies , Young Adult
11.
Exp Parasitol ; 191: 9-18, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29890165

ABSTRACT

Schistosomiasis mansoni is involved in hepatic fibrogenesis and portal hypertension. Previous studies proved that blockade of some components of the renin-angiotensin system (RAS) reduce liver fibrogenesis. However, the effects of inhibition of early stages of RAS pathway in schistosomal fibrosis have not been studied yet. Thus, the aim of this study was to compare the role of different antihypertensive drugs on hepatic fibrosis in murine schistosomiasis. BALB/c mice (n = 50) weighing 20g were subjected to inoculation of 50 cercariae and submitted to different treatments: aliskiren, 50 mg/kg (n = 10); bradykinin, 2 µg/kg (n = 5); losartan, 10 mg/kg (n = 10); lisinopril 10 mg/kg (n = 5) and control, proportional volume vehicle (n = 5); daily for 14 weeks. Six animals were not subjected to cercariae inoculation or any type of treatment. Ultrasound, histological, immunohistochemical and proteomic analyzes were performed to evaluate markers associated with hepatic fibrogenesis. The hepatic areas stained with Sirius red and thenumber of cells marked by α-SMA in animals treated with aliskiren, bradykinin, lisinopril and losartan were diminished when compared to control group, demonstrating reduced hepatic fibrosis after RAS blockade. These results were reinforced by ultrasonography analysis and protein expression of TGFß. These findings demonstrated the effect of RAS inhibition on hepatic fibrosis in murine schistosomiasis, with the most evident results being observed in the losartan and aliskiren treated groups. The main mechanisms underlying this process appear to involve anti-fibrogenic activity through the inhibition of collagen and TGFß synthesis.


Subject(s)
Liver Cirrhosis/drug therapy , Renin-Angiotensin System/drug effects , Schistosomiasis mansoni/complications , Amides/pharmacology , Amides/therapeutic use , Angiotensin II Type 1 Receptor Blockers/pharmacology , Angiotensin II Type 1 Receptor Blockers/therapeutic use , Angiotensin-Converting Enzyme Inhibitors/pharmacology , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Animals , Antihypertensive Agents/pharmacology , Antihypertensive Agents/therapeutic use , Bradykinin/pharmacology , Bradykinin/therapeutic use , Fumarates/pharmacology , Fumarates/therapeutic use , Lisinopril/pharmacology , Lisinopril/therapeutic use , Liver/drug effects , Liver/pathology , Liver Cirrhosis/parasitology , Losartan/pharmacology , Losartan/therapeutic use , Male , Mice , Mice, Inbred BALB C , Nitric Oxide Synthase Type III/drug effects , Nitric Oxide Synthase Type III/genetics , Nitric Oxide Synthase Type III/metabolism , Proto-Oncogene Mas , Proto-Oncogene Proteins/drug effects , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins/metabolism , Receptors, G-Protein-Coupled/drug effects , Receptors, G-Protein-Coupled/genetics , Receptors, G-Protein-Coupled/metabolism , Renin/drug effects , Renin/genetics , Renin/metabolism , Schistosomiasis mansoni/drug therapy , Schistosomiasis mansoni/pathology , Tissue Inhibitor of Metalloproteinase-1/drug effects , Tissue Inhibitor of Metalloproteinase-1/genetics , Tissue Inhibitor of Metalloproteinase-1/metabolism , Transforming Growth Factor beta1/drug effects , Transforming Growth Factor beta1/genetics , Transforming Growth Factor beta1/metabolism , Vasodilator Agents/pharmacology , Vasodilator Agents/therapeutic use , p38 Mitogen-Activated Protein Kinases/drug effects , p38 Mitogen-Activated Protein Kinases/genetics , p38 Mitogen-Activated Protein Kinases/metabolism
12.
Mol Microbiol ; 100(5): 841-59, 2016 06.
Article in English | MEDLINE | ID: mdl-26878695

ABSTRACT

Here, we investigated which stress responses were influenced by the MpkC and SakA mitogen-activated protein kinases of the high-osmolarity glycerol (HOG) pathway in the fungal pathogen Aspergillus fumigatus. The ΔsakA and the double ΔmpkC ΔsakA mutants were more sensitive to osmotic and oxidative stresses, and to cell wall damaging agents. Both MpkC::GFP and SakA::GFP translocated to the nucleus upon osmotic stress and cell wall damage, with SakA::GFP showing a quicker response. The phosphorylation state of MpkA was determined post exposure to high concentrations of congo red and Sorbitol. In the wild-type strain, MpkA phosphorylation levels progressively increased in both treatments. In contrast, the ΔsakA mutant had reduced MpkA phosphorylation, and surprisingly, the double ΔmpkC ΔsakA had no detectable MpkA phosphorylation. A. fumigatus ΔsakA and ΔmpkC were virulent in mouse survival experiments, but they had a 40% reduction in fungal burden. In contrast, the ΔmpkC ΔsakA double mutant showed highly attenuated virulence, with approximately 50% mice surviving and a 75% reduction in fungal burden. We propose that both cell wall integrity (CWI) and HOG pathways collaborate, and that MpkC could act by modulating SakA activity upon exposure to several types of stresses and during CW biosynthesis.


Subject(s)
Aspergillus fumigatus/enzymology , Aspergillus fumigatus/pathogenicity , Cell Wall/metabolism , Fungal Proteins/metabolism , Mitogen-Activated Protein Kinases/metabolism , Animals , Aspergillus fumigatus/drug effects , Aspergillus fumigatus/genetics , Biofilms/growth & development , Cell Wall/pathology , Congo Red/pharmacology , Fungal Proteins/genetics , Gene Expression Regulation, Fungal , Mice , Mitogen-Activated Protein Kinases/genetics , Mutation , Osmotic Pressure , Oxidative Stress , Phosphorylation , Signal Transduction , Sorbitol/pharmacology , Stress, Physiological , Virulence
13.
Immunology ; 148(1): 102-13, 2016 May.
Article in English | MEDLINE | ID: mdl-26840507

ABSTRACT

M1 macrophages are more effective in the induction of the inflammatory response and clearance of Mycobacterium tuberculosis than M2 macrophages. Infected C57BL/6 mice generate a stronger cellular immune response compared with BALB/c mice. We hypothesized that infected C57BL/6 mice would exhibit a higher frequency and function of M1 macrophages than infected BALB/c mice. Our findings show a higher ratio of macrophages to M2 macrophages in the lungs of chronically infected C57BL/6 mice compared with BALB/c mice. However, there was no difference in the functional ability of M1 and M2 macrophages for the two strains in vitro. In vivo, a deleterious role for M2 macrophages was confirmed by M2 cell transfer, which rendered the infected C57BL/6, but not the BALB/c mice, more susceptible and resulted in mild lung inflammation compared with C57BL/6 mice that did not undergo cell transfer. M1 cell transfer induced a higher inflammatory response, although not protective, in infected BALB/c mice compared with their counterparts that did not undergo cell transfer. These findings demonstrate that an inflammation mediated by M1 macrophages may not induce bacterial tolerance because protection depends on the host genetic background, which drives the magnitude of the inflammatory response against M. tuberculosis in the pulmonary microenvironment. The contribution of our findings is that although M1 macrophage is an effector leucocyte with microbicidal machinery, its dominant role depends on the balance of M1 and M2 subsets, which is driven by the host genetic background.


Subject(s)
Lung/immunology , Macrophages/immunology , Mycobacterium tuberculosis/immunology , Tuberculosis/immunology , Animals , Disease Susceptibility , Female , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Muscle, Smooth, Vascular/enzymology , Nitric Oxide Synthase Type II/analysis , Species Specificity
14.
Mol Microbiol ; 96(1): 42-54, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25597841

ABSTRACT

Aspergillus fumigatus is a fungal pathogen that is capable of adapting to different host niches and to avoid host defenses. An enhanced understanding of how, and which, A. fumigatus signal transduction pathways are engaged in the regulation of these processes is essential for the development of improved disease control strategies. Protein phosphatases are central to numerous signal transduction pathways. To comprehend the functions of protein phosphatases in A. fumigatus, 32 phosphatase catalytic subunit encoding genes were identified. We have recognized PtcB as one of the phosphatases involved in the high osmolarity glycerol response (HOG) pathway. The ΔptcB mutant has both increased phosphorylation of the p38 MAPK (SakA) and expression of osmo-dependent genes. The ΔptcB strain was more sensitive to cell wall damaging agents, had increased chitin and ß-1,3-glucan, and impaired biofilm formation. The ΔptcB strain was avirulent in a murine model of invasive pulmonary aspergillosis. These results stress the importance of the HOG pathway in the regulation of pathogenicity determinants and virulence in A. fumigatus.


Subject(s)
Aspergillus fumigatus/physiology , Aspergillus fumigatus/pathogenicity , Gene Expression Regulation, Fungal , Glycerol/metabolism , Osmolar Concentration , Phosphoric Monoester Hydrolases/genetics , Animals , Aspergillus fumigatus/genetics , Aspergillus fumigatus/ultrastructure , Biofilms/growth & development , Cell Wall/metabolism , Chitin/metabolism , Computational Biology , Disease Models, Animal , Fungal Proteins/genetics , Fungal Proteins/metabolism , Mice , Mutation , Phosphoric Monoester Hydrolases/metabolism , Signal Transduction , beta-Glucans/metabolism
15.
Eukaryot Cell ; 14(8): 728-44, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25911225

ABSTRACT

Aspergillus fumigatus is an opportunistic pathogenic fungus able to infect immunocompromised patients, eventually causing disseminated infections that are difficult to control and lead to high mortality rates. It is important to understand how the signaling pathways that regulate these factors involved in virulence are orchestrated. Protein phosphatases are central to numerous signal transduction pathways. Here, we characterize the A. fumigatus protein phosphatase 2A SitA, the Saccharomyces cerevisiae Sit4p homologue. The sitA gene is not an essential gene, and we were able to construct an A. fumigatus null mutant. The ΔsitA strain had decreased MpkA phosphorylation levels, was more sensitive to cell wall-damaging agents, had increased ß-(1,3)-glucan and chitin, was impaired in biofilm formation, and had decreased protein kinase C activity. The ΔsitA strain is more sensitive to several metals and ions, such as MnCl2, CaCl2, and LiCl, but it is more resistant to ZnSO4. The ΔsitA strain was avirulent in a murine model of invasive pulmonary aspergillosis and induces an augmented tumor necrosis factor alpha (TNF-α) response in mouse macrophages. These results stress the importance of A. fumigatus SitA as a possible modulator of PkcA/MpkA activity and its involvement in the cell wall integrity pathway.


Subject(s)
Aspergillus fumigatus/metabolism , Biofilms/growth & development , Cation Transport Proteins/metabolism , Cell Adhesion/physiology , Cell Wall/metabolism , Phosphoric Monoester Hydrolases/metabolism , Virulence/physiology , Animals , Chitin/metabolism , Disease Models, Animal , Female , Fungal Proteins/metabolism , Invasive Pulmonary Aspergillosis/metabolism , Invasive Pulmonary Aspergillosis/microbiology , Lung Diseases, Fungal/metabolism , Lung Diseases, Fungal/microbiology , Macrophages/microbiology , Mice , Mice, Inbred BALB C , Signal Transduction/physiology , Tumor Necrosis Factor-alpha/metabolism
16.
Mol Microbiol ; 94(3): 655-74, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25196896

ABSTRACT

Aspergillus fumigatus is an opportunistic pathogen and allergen of mammals. Calcium signalling is essential for A. fumigatus pathogenicity and is regulated by the CrzA transcription factor. We used ChIP-seq (Chromatin Immunoprecipitation DNA sequencing) to explore CrzA gene targets in A. fumigatus. In total, 165 potential binding peaks including 102 directly regulated genes were identified, resulting in the prediction of the A[GT][CG]CA[AC][AG] CrzA-binding motif. The 102 CrzA putatively regulated genes exhibited a diverse array of functions. The phkB (Afu3g12530) histidine kinase and the sskB (Afu1g10940) MAP kinase kinase kinase of the HOG (high-osmolarity glycerol response) pathway were regulated by CrzA. Several members of the two-component system (TCS) and the HOG pathway were more sensitive to calcium. CrzA::GFP was translocated to the nucleus upon osmotic stress. CrzA is important for the phosphorylation of the SakA MAPK in response to osmotic shock. The ΔsskB was more sensitive to CaCl2 , NaCl, and paraquat stress, while being avirulent in a murine model of invasive pulmonary aspergillosis. The presence of CaCl2 and osmotic stresses resulted in synergistic inhibition of ΔcrzA and ΔsskB growth. These results suggest there is a genetic interaction between the A. fumigatus calcineurin-CrzA and HOG pathway that is essential for full virulence.


Subject(s)
Aspergillus fumigatus/physiology , Fungal Proteins/metabolism , Gene Expression Regulation, Fungal , Glycerol/metabolism , Osmotic Pressure , Signal Transduction , Stress, Physiological , Animals , Aspergillus fumigatus/genetics , Aspergillus fumigatus/growth & development , Aspergillus fumigatus/pathogenicity , Chromatin Immunoprecipitation , DNA, Fungal/chemistry , DNA, Fungal/genetics , Fungal Proteins/genetics , Gene Deletion , Mammals , Mice , Osmolar Concentration , Protein Binding , Regulon , Sequence Analysis, DNA , Virulence
17.
Nutrients ; 16(5)2024 Feb 24.
Article in English | MEDLINE | ID: mdl-38474762

ABSTRACT

INTRODUCTION: chronic low-grade inflammation, or inflammaging, emerges as a crucial element in the aging process and is associated with cardiovascular and neurological diseases, sarcopenia, and malnutrition. Evidence suggests that omega-3 fatty acids present a potential therapeutic agent in the prevention and treatment of inflammatory diseases, mitigating oxidative stress, and improving muscle mass, attributes that are particularly relevant in the context of aging. The objective of the present study was to evaluate the effectiveness of supplementation with omega-3 fish oil in improving the immune response and oxidative stress in knockout mice for interleukin IL-10 (IL-10-/-). MATERIAL AND METHODS: female C57BL/6 wild-type (WT) and interleukin IL-10 knockout (IL-10-/-) mice were fed during 90 days with a standard diet (control groups), or they were fed/supplemented with 10% of the omega-3 polyunsaturated fatty acid diet (omega-3 groups). Muscle, liver, intestinal, and mesenteric lymph node tissue were collected for analysis. RESULTS: the IL-10-/-+O3 group showed greater weight gain compared to the WT+O3 (p = 0.001) group. The IL-10-/-+O3 group exhibited a higher frequency of regulatory T cells than the IL-10-/- group (p = 0.001). It was found that animals in the IL-10-/-+O3 group had lower levels of steatosis when compared to the IL-10-/- group (p = 0.017). There was even greater vitamin E activity in the WT group compared to the IL-10-/-+O3 group (p = 0.001) and WT+O3 compared to IL-10-/-+O3 (p = 0.002), and when analyzing the marker of oxidative stress, MDA, an increase in lipid peroxidation was found in the IL-10-/-+O3 group when compared to the IL-10-/- group (p = 0.03). Muscle tissue histology showed decreased muscle fibers in the IL-10-/-+O3, IL-10-/-, and WT+O3 groups. CONCLUSION: the findings show a decrease in inflammation, an increase in oxidative stress markers, and a decrease in antioxidant markers in the IL-10-/-+O3 group, suggesting that supplementation with omega-3 fish oil might be a potential intervention for inflammaging that characterizes the aging process and age-related diseases.


Subject(s)
Fatty Acids, Omega-3 , Female , Mice , Animals , Fatty Acids, Omega-3/pharmacology , Antioxidants/pharmacology , T-Lymphocytes, Regulatory/metabolism , Mice, Knockout , Interleukin-10/metabolism , Mice, Inbred C57BL , Fish Oils/pharmacology , Oxidative Stress , Dietary Supplements , Liver/metabolism , Inflammation/metabolism
18.
Fungal Genet Biol ; 60: 74-86, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23856128

ABSTRACT

Candida albicans is the most common fungal pathogen of humans, forming both commensal and opportunistic pathogenic interactions, causing a variety of skin and soft tissue infections in healthy people. In immunocompromised patients C. albicans can result in invasive, systemic infections that are associated with a high incidence of mortality. Propolis is a complex mixture of several resinous substances which are collected from plants by bees. Here, we demonstrated the fungicidal activity of propolis against all three morphogenetic types of C. albicans and that propolis-induced cell death was mediated via metacaspase and Ras signaling. To identify genes that were involved in propolis tolerance, we screened ~800 C. albicans homozygous deletion mutants for decreased tolerance to propolis. Fifty-one mutant strains were identified as being hypersensitive to propolis including seventeen genes involved in cell adhesion, biofilm formation, filamentous growth, phenotypic switching and pathogenesis (HST7, GIN4, VPS34, HOG1, ISW2, SUV3, MDS3, HDA2, KAR3, YHB1, NUP85, CDC10, MNN9, ACE2, FKH2, and SNF5). We validated these results by showing that propolis inhibited the transition from yeast-like to hyphal growth. Propolis was shown to contain compounds that conferred fluorescent properties to C. albicans cells. Moreover, we have shown that a topical pharmaceutical preparation, based upon propolis, was able to control C. albicans infections in a mouse model for vulvovaginal candidiasis. Our results strongly indicate that propolis could be used as a strategy for controlling candidiasis.


Subject(s)
Antifungal Agents/pharmacology , Candida albicans/drug effects , Candida albicans/genetics , Candidiasis, Vulvovaginal/drug therapy , Propolis/pharmacology , Animals , Anti-Infective Agents/pharmacology , Candidiasis, Vulvovaginal/microbiology , Caspases/metabolism , Female , Mice , Mice, Inbred BALB C , Proto-Oncogene Proteins p21(ras)/metabolism
20.
Pediatr Blood Cancer ; 60(11): 1809-16, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23788275

ABSTRACT

BACKGROUND: Pediatric adrenocortical tumors (ACT) are rare malignancies and treatment has a small impact on survival in advanced disease and the discovery of potential target genes could be important in new therapeutic approaches. METHODS: The mRNA expression levels of spindle checkpoint genes AURKA, AURKB, BUB, and BUBR1 were analyzed in 60 children with ACT by quantitative real time PCR. The anticancer effect of ZM447439, an experimental AURK inhibitor, was analyzed in a primary childhood ACT culture carrying the TP53 p.R337H mutation. RESULTS: A significant association was observed between malignancy as defined by Weiss score ≥3 and higher AURKA (2.0-fold, P = 0.01), AURKB (7.0-fold, P = 0.007), and BUBR1 (5.8-fold, P = 0.007) gene expression, and between unfavorable event (death or relapse) and higher expression of AURKA (6.0-fold, P = 0.034) and AURKB (17-fold, P = 0.013). Overexpression of AURKA and AURKB was associated with lower event-free survival in uni- (P < 0.001 and P = 0.006, respectively) and multivariate (P = 0.002 and P = 0.03, respectively) analysis. Significant lower Event free survival (EFS) was also observed in patients with moderate/strong immunostaining to AURKA (P = 0.012) and AURKB (P = 0.045). ZM447439 was able to induce inhibition of proliferation and colony formation in a primary childhood ACT culture carrying the TP53 p.R337H mutation. CONCLUSION: Our results suggest that AURKA and AURKB overexpression in pediatric ACT may be related to more aggressive disease and the inhibition of these proteins could be an interesting approach for the treatment of these tumors.


Subject(s)
Adrenocortical Carcinoma/enzymology , Adrenocortical Carcinoma/genetics , M Phase Cell Cycle Checkpoints/genetics , Protein Serine-Threonine Kinases/biosynthesis , Adolescent , Adrenocortical Carcinoma/pathology , Antineoplastic Agents/pharmacology , Aurora Kinase A , Aurora Kinase B , Aurora Kinases , Benzamides/pharmacology , Cell Proliferation/drug effects , Cells, Cultured , Child , Child, Preschool , Disease-Free Survival , Enzyme Inhibitors/pharmacology , Female , Humans , Immunohistochemistry , Infant , Kaplan-Meier Estimate , Male , Prognosis , Proportional Hazards Models , Protein Serine-Threonine Kinases/genetics , Quinazolines/pharmacology , RNA, Messenger/analysis , Real-Time Polymerase Chain Reaction , Transcriptome
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