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1.
Antioxidants (Basel) ; 12(6)2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37371878

RESUMO

Less invasive surfactant administration techniques, together with nasal continuous airway pressure (LISA-nCPAP) ventilation, an emerging noninvasive ventilation (NIV) technique in neonatology, are gaining more significance, even in extremely premature newborns (ELBW), under 27 weeks of gestational age. In this review, studies on LISA-nCPAP are compiled with an emphasis on short- and long-term morbidities associated with prematurity. Several perinatal preventative and therapeutic investigations are also discussed in order to start integrated therapies as numerous organ-saving techniques in addition to lung-protective ventilations. Two thirds of immature newborns can start their lives on NIV, and one third of them never need mechanical ventilation. With adjuvant intervention, these ratios are expected to be increased, resulting in better outcomes. Optimized cardiopulmonary transition, especially physiologic cord clamping, could have an additively beneficial effect on patient outcomes gained from NIV. Organ development and angiogenesis are strictly linked not only in the immature lung and retina, but also possibly in the kidney, and optimized interventions using angiogenic growth factors could lead to better morbidity-free survival. Corticosteroids, caffeine, insulin, thyroid hormones, antioxidants, N-acetylcysteine, and, moreover, the immunomodulatory components of mother's milk are also discussed as adjuvant treatments, since immature newborns deserve more complex neonatal interventions.

2.
Redox Biol ; 57: 102504, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36240620

RESUMO

Vulnerable atherosclerotic plaques with hemorrhage considerably contribute to cardiovascular morbidity and mortality. Calcification is the main characteristic of advanced atherosclerotic lesions and calcified aortic valve disease (CAVD). Lyses of red blood cells and hemoglobin (Hb) release occur in human hemorrhagic complicated lesions. During the interaction of cell-free Hb with plaque constituents, Hb is oxidized to ferric and ferryl states accompanied by oxidative changes of the globin moieties and heme release. Accumulation of both ferryl-Hb and metHb has been observed in atherosclerotic plaques. The oxidation hotspots in the globin chain are the cysteine and tyrosine amino acids associated with the generation of Hb dimers, tetramers and polymers. Moreover, fragmentation of Hb occurs leading to the formation of globin-derived peptides. A series of these pro-atherogenic cellular responses can be suppressed by hydrogen sulfide (H2S). Since H2S has been explored to exhibit a wide range of physiologic functions to maintain vascular homeostasis, it is not surprising that H2S may play beneficial effects in the progression of atherosclerosis. In the present review, we summarize the findings about the effects of H2S on atherosclerosis and CAVD with a special emphasis on the oxidation of Hb/heme in atherosclerotic plaque development and vascular calcification.

3.
Int J Mol Sci ; 22(17)2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34502172

RESUMO

Vascular calcification associated with high plasma phosphate (Pi) level is a frequent complication of hyperglycemia, diabetes mellitus, and chronic kidney disease. BGP-15 is an emerging anti-diabetic drug candidate. This study was aimed to explore whether BGP-15 inhibits high Pi-induced calcification of human vascular smooth muscle cells (VSMCs) under normal glucose (NG) and high glucose (HG) conditions. Exposure of VSMCs to Pi resulted in accumulation of extracellular calcium, elevated cellular Pi uptake and intracellular pyruvate dehydrogenase kinase-4 (PDK-4) level, loss of smooth muscle cell markers (ACTA, TAGLN), and enhanced osteochondrogenic gene expression (KLF-5, Msx-2, Sp7, BMP-2). Increased Annexin A2 and decreased matrix Gla protein (MGP) content were found in extracellular vesicles (EVs). The HG condition markedly aggravated Pi-induced VSMC calcification. BGP-15 inhibited Pi uptake and PDK-4 expression that was accompanied by the decreased nuclear translocation of KLF-5, Msx-2, Sp7, retained VSMC markers (ACTA, TAGLN), and decreased BMP-2 in both NG and HG conditions. EVs exhibited increased MGP content and decreased Annexin A2. Importantly, BGP-15 prevented the deposition of calcium in the extracellular matrix. In conclusion, BGP-15 inhibits Pi-induced osteochondrogenic phenotypic switch and mineralization of VSMCs in vitro that make BGP-15 an ideal candidate to attenuate both diabetic and non-diabetic vascular calcification.


Assuntos
Hiperglicemia/metabolismo , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Oximas/farmacologia , Fosfatos/metabolismo , Piperidinas/farmacologia , Calcificação Vascular/etiologia , Calcificação Vascular/metabolismo , Biomarcadores , Glicemia , Células Cultivadas , Matriz Extracelular/metabolismo , Regulação da Expressão Gênica , Hiperglicemia/sangue , Osteoblastos/metabolismo , Fosfatos/efeitos adversos , Calcificação Vascular/tratamento farmacológico
4.
Int J Mol Sci ; 22(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206377

RESUMO

Infiltration of red blood cells into atheromatous plaques and oxidation of hemoglobin (Hb) and lipoproteins are implicated in the pathogenesis of atherosclerosis. α1-microglobulin (A1M) is a radical-scavenging and heme-binding protein. In this work, we examined the origin and role of A1M in human atherosclerotic lesions. Using immunohistochemistry, we observed a significant A1M immunoreactivity in atheromas and hemorrhaged plaques of carotid arteries in smooth muscle cells (SMCs) and macrophages. The most prominent expression was detected in macrophages of organized hemorrhage. To reveal a possible inducer of A1M expression in ruptured lesions, we exposed aortic endothelial cells (ECs), SMCs and macrophages to heme, Oxy- and FerrylHb. Both heme and FerrylHb, but not OxyHb, upregulated A1M mRNA expression in all cell types. Importantly, only FerrylHb induced A1M protein secretion in aortic ECs, SMCs and macrophages. To assess the possible function of A1M in ruptured lesions, we analyzed Hb oxidation and heme-catalyzed lipid peroxidation in the presence of A1M. We showed that recombinant A1M markedly inhibited Hb oxidation and heme-driven oxidative modification of low-density lipoproteins as well plaque lipids derived from atheromas. These results demonstrate the presence of A1M in atherosclerotic plaques and suggest its induction by heme and FerrylHb in the resident cells.


Assuntos
alfa-Globulinas/metabolismo , Aterosclerose/etiologia , Aterosclerose/metabolismo , Heme/metabolismo , Hemoglobinas/metabolismo , Peroxidação de Lipídeos , Oxirredução , Aterosclerose/patologia , Biomarcadores , Doenças das Artérias Carótidas/etiologia , Doenças das Artérias Carótidas/metabolismo , Doenças das Artérias Carótidas/patologia , Células Cultivadas , Progressão da Doença , Suscetibilidade a Doenças , Hemorragia/metabolismo , Hemorragia/patologia , Humanos , Imuno-Histoquímica , Miócitos de Músculo Liso/metabolismo , Placa Aterosclerótica/etiologia , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia
5.
Sci Rep ; 11(1): 10435, 2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-34001932

RESUMO

Hemorrhage and hemolysis with subsequent heme release are implicated in many pathologies. Endothelial cells (ECs) encounter large amount of free heme after hemolysis and are at risk of damage from exogenous heme. Here we show that hemorrhage aggravates endoplasmic reticulum (ER) stress in human carotid artery plaques compared to healthy controls or atheromas without hemorrhage as demonstrated by RNA sequencing and immunohistochemistry. In EC cultures, heme also induces ER stress. In contrast, if cultured ECs are pulsed with heme arginate, cells become resistant to heme-induced ER (HIER) stress that is associated with heme oxygenase-1 (HO-1) and ferritin induction. Knocking down HO-1, HO-2, biliverdin reductase, and ferritin show that HO-1 is the ultimate cytoprotectant in acute HIER stress. Carbon monoxide-releasing molecules (CORMs) but not bilirubin protects cultured ECs from HIER stress via HO-1 induction, at least in part. Knocking down HO-1 aggravates heme-induced cell death that cannot be counterbalanced with any known cell death inhibitors. We conclude that endothelium and perhaps other cell types can be protected from HIER stress by induction of HO-1, and heme-induced cell death occurs via HIER stress that is potentially involved in the pathogenesis of diverse pathologies with hemolysis and hemorrhage including atherosclerosis.


Assuntos
Estenose das Carótidas/complicações , Heme Oxigenase-1/metabolismo , Heme/metabolismo , Hemorragia/patologia , Placa Aterosclerótica/complicações , Biópsia , Estenose das Carótidas/sangue , Linhagem Celular , Estresse do Retículo Endoplasmático , Células Endoteliais/patologia , Endotélio Vascular/citologia , Endotélio Vascular/patologia , Técnicas de Silenciamento de Genes , Voluntários Saudáveis , Heme Oxigenase (Desciclizante)/genética , Heme Oxigenase (Desciclizante)/metabolismo , Heme Oxigenase-1/genética , Hemólise , Hemorragia/etiologia , Humanos , Placa Aterosclerótica/sangue
6.
Int J Mol Sci ; 22(1)2020 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-33374506

RESUMO

Over the past decades, substantial work has established that hemoglobin oxidation and heme release play a pivotal role in hemolytic/hemorrhagic disorders. Recent reports have shown that oxidized hemoglobins, globin-derived peptides, and heme trigger diverse biological responses, such as toll-like receptor 4 activation with inflammatory response, reprogramming of cellular metabolism, differentiation, stress, and even death. Here, we discuss these cellular responses with particular focus on their mechanisms that are linked to the pathological consequences of hemorrhage and hemolysis. In recent years, endogenous gasotransmitters, such as carbon monoxide (CO) and hydrogen sulfide (H2S), have gained a lot of interest in connection with various human pathologies. Thus, many CO and H2S-releasing molecules have been developed and applied in various human disorders, including hemolytic and hemorrhagic diseases. Here, we discuss our current understanding of oxidized hemoglobin and heme-induced cell and tissue damage with particular focus on inflammation, cellular metabolism and differentiation, and endoplasmic reticulum stress in hemolytic/hemorrhagic human diseases, and the potential beneficial role of CO and H2S in these pathologies. More detailed mechanistic insights into the complex pathology of hemolytic/hemorrhagic diseases through heme oxygenase-1/CO as well as H2S pathways would reveal new therapeutic approaches that can be exploited for clinical benefit.


Assuntos
Monóxido de Carbono/uso terapêutico , Heme Oxigenase (Desciclizante)/metabolismo , Hemólise/efeitos dos fármacos , Sulfeto de Hidrogênio/uso terapêutico , Vasculite por IgA/tratamento farmacológico , Vasculite por IgA/metabolismo , Animais , Monóxido de Carbono/metabolismo , Monóxido de Carbono/farmacologia , Gerenciamento Clínico , Suscetibilidade a Doenças , Metabolismo Energético , Heme/metabolismo , Heme Oxigenase-1/metabolismo , Hemoglobinas/química , Hemoglobinas/metabolismo , Humanos , Sulfeto de Hidrogênio/metabolismo , Sulfeto de Hidrogênio/farmacologia , Vasculite por IgA/diagnóstico , Vasculite por IgA/etiologia , Metabolismo dos Lipídeos , Lipoproteínas LDL/metabolismo , Monócitos/imunologia , Monócitos/metabolismo , Oxirredução/efeitos dos fármacos , Peptídeos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo
7.
Int J Mol Sci ; 21(13)2020 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-32635347

RESUMO

Hemoglobin, heme and iron are implicated in the progression of atherosclerosis. Therefore, we investigated whether the hydrophobic fungal iron chelator siderophore, desferricoprogen (DFC) inhibits atherosclerosis. DFC reduced atherosclerotic plaque formation in ApoE-/- mice on an atherogenic diet. It lowered the plasma level of oxidized LDL (oxLDL) and inhibited lipid peroxidation in aortic roots. The elevated collagen/elastin content and enhanced expression of adhesion molecule VCAM-1 were decreased. DFC diminished oxidation of Low-density Lipoprotein (LDL) and plaque lipids catalyzed by heme or hemoglobin. Formation of foam cells, uptake of oxLDL by macrophages, upregulation of CD36 and increased expression of TNF-α were reduced by DFC in macrophages. TNF-triggered endothelial cell activation (vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecules (ICAMs), E-selectin) and increased adhesion of monocytes to endothelium were attenuated. The increased endothelial permeability and intracellular gap formation provoked by TNF-α was also prevented by DFC. DFC acted as a cytoprotectant in endothelial cells and macrophages challenged with a lethal dose of oxLDL and lowered the expression of stress-responsive heme oxygenase-1 as sublethal dose was employed. Saturation of desferrisiderophore with iron led to the loss of the beneficial effects. We demonstrated that DFC accumulated within the atheromas of the aorta in ApoE-/- mice. DFC represents a novel therapeutic approach to control the progression of atherosclerosis.


Assuntos
Dicetopiperazinas/farmacologia , Ácidos Hidroxâmicos/farmacologia , Placa Aterosclerótica/prevenção & controle , Sideróforos/farmacologia , Animais , Aorta/diagnóstico por imagem , Aorta/efeitos dos fármacos , Aorta/metabolismo , Aterosclerose/tratamento farmacológico , Aterosclerose/metabolismo , Aterosclerose/patologia , Dieta Aterogênica , Dicetopiperazinas/farmacocinética , Modelos Animais de Doenças , Progressão da Doença , Células Espumosas/efeitos dos fármacos , Células Espumosas/patologia , Heme/metabolismo , Ácidos Hidroxâmicos/farmacocinética , Peroxidação de Lipídeos/efeitos dos fármacos , Lipoproteínas LDL/metabolismo , Ativação de Macrófagos/efeitos dos fármacos , Imageamento por Ressonância Magnética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Neurospora crassa/química , Estresse Oxidativo/efeitos dos fármacos , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , Tomografia por Emissão de Pósitrons , Sideróforos/farmacocinética
8.
BMC Med Genet ; 21(1): 61, 2020 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-32216767

RESUMO

BACKGROUND: Wolcott-Rallison Syndrome (WRS) is a rare autosomal recessive disease that is the most common cause of neonatal diabetes in consanguineous families. WRS is caused by various genetic alterations of the Eukaryotic Translation Initiation Factor 2-Alpha Kinase 3 (EIF2AK3) gene. METHODS: Genetic analysis of a consanguineous family where two children were diagnosed with WRS was performed by Sanger sequencing. The altered protein was investigated by in vitro cloning, expression and immunohistochemistry. RESULTS: The first cases in Hungary, - two patients in one family, where the parents were fourth-degree cousins - showed the typical clinical features of WRS: early onset diabetes mellitus with hyperglycemia, growth retardation, infection-induced multiple organ failure. The genetic background of the disease was a novel alteration in the EIF2AK3 gene involving the splice site of exon 11- intron 11-12 boundary: g.53051_53062delinsTG. According to cDNA sequencing this created a new splice site and resulted in a frameshift and the development of an early termination codon at amino acid position 633 (p.Pro627AspfsTer7). Based on in vitro cloning and expression studies, the truncated protein was functionally inactive. Immunohistochemistry revealed that the intact protein was absent in the islets of pancreas, furthermore insulin expressing cells were also dramatically diminished. Elevated GRP78 and reduced CHOP protein expression were observed in the liver. CONCLUSIONS: The novel genetic alteration causing the absence of the EIF2AK3 protein resulted in insufficient handling of severe endoplasmic reticulum stress, leading to liver failure and demise of the patients.


Assuntos
Diabetes Mellitus Tipo 1/genética , Epífises/anormalidades , Mutação INDEL , Osteocondrodisplasias/genética , Sítios de Splice de RNA/genética , eIF-2 Quinase/genética , Pré-Escolar , Consanguinidade , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/patologia , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático/genética , Epífises/patologia , Evolução Fatal , Feminino , Mutação da Fase de Leitura , Humanos , Hungria , Lactente , Falência Hepática/complicações , Falência Hepática/genética , Falência Hepática/patologia , Osteocondrodisplasias/diagnóstico , Osteocondrodisplasias/patologia , Linhagem , Irmãos , Viroses/complicações , Viroses/patologia
9.
Oxid Med Cell Longev ; 2020: 3721383, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32184915

RESUMO

Intraplaque hemorrhage frequently occurs in atherosclerotic plaques resulting in cell-free hemoglobin, which is oxidized to ferryl hemoglobin (FHb) in the highly oxidative environment. Osteoclast-like cells (OLCs) derived from macrophages signify a counterbalance mechanism for calcium deposition in atherosclerosis. Our aim was to investigate whether oxidized hemoglobin alters osteoclast formation, thereby affecting calcium removal from mineralized atherosclerotic lesions. RANKL- (receptor activator of nuclear factor kappa-Β ligand-) induced osteoclastogenic differentiation and osteoclast activity of RAW264.7 cells were studied in response to oxidized hemoglobin via assessing bone resorption activity, expression of osteoclast-specific genes, and the activation of signalization pathways. OLCs in diseased human carotid arteries were assessed by immunohistochemistry. FHb, but not ferrohemoglobin, decreased bone resorption activity and inhibited osteoclast-specific gene expression (tartrate-resistant acid phosphatase, calcitonin receptor, and dendritic cell-specific transmembrane protein) induced by RANKL. In addition, FHb inhibited osteoclastogenic signaling pathways downstream of RANK (receptor activator of nuclear factor kappa-Β). It prevented the induction of TRAF6 (tumor necrosis factor (TNF) receptor-associated factor 6) and c-Fos, phosphorylation of p-38 and JNK (c-Jun N-terminal kinase), and nuclear translocation of NFκB (nuclear factor kappa-Β) and NFATc1 (nuclear factor of activated T-cells, cytoplasmic 1). These effects were independent of heme oxygenase-1 demonstrated by knocking down HO-1 gene in RAW264.7 cells and in mice. Importantly, FHb competed with RANK for RANKL binding suggesting possible mechanisms by which FHb impairs osteoclastic differentiation. In diseased human carotid arteries, OLCs were abundantly present in calcified plaques and colocalized with regions of calcium deposition, while the number of these cells were lower in hemorrhagic lesions exhibiting accumulation of FHb despite calcium deposition. We conclude that FHb inhibits RANKL-induced osteoclastic differentiation of macrophages and suggest that accumulation of FHb in a calcified area of atherosclerotic lesion with hemorrhage retards the formation of OLCs potentially impairing calcium resorption.


Assuntos
Diferenciação Celular , Hemoglobinas/farmacologia , Hemorragia/patologia , Macrófagos/patologia , Osteoclastos/patologia , Placa Aterosclerótica/patologia , Animais , Reabsorção Óssea/patologia , Calcinose , Artérias Carótidas/efeitos dos fármacos , Artérias Carótidas/patologia , Diferenciação Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Heme Oxigenase-1/metabolismo , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Biológicos , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Osteogênese/efeitos dos fármacos , Oxirredução/efeitos dos fármacos , Placa Aterosclerótica/genética , Ligação Proteica/efeitos dos fármacos , Ligante RANK/genética , Ligante RANK/metabolismo , Células RAW 264.7 , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Transdução de Sinais/efeitos dos fármacos
10.
Int J Mol Sci ; 20(15)2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31357546

RESUMO

The prevalence of vascular disorders continues to rise worldwide. Parallel with that, new pathophysiological pathways have been discovered, providing possible remedies for prevention and therapy in vascular diseases. Growing evidence suggests that endoplasmic reticulum (ER) stress is involved in a number of vasculopathies, including atherosclerosis, vascular brain events, and diabetes. Heme, which is released from hemoglobin or other heme proteins, triggers various pathophysiological consequence, including heme stress as well as ER stress. The potentially toxic free heme is converted by heme oxygenases (HOs) into carbon monoxide (CO), iron, and biliverdin (BV), the latter of which is reduced to bilirubin (BR). Redox-active iron is oxidized and stored by ferritin, an iron sequestering protein which exhibits ferroxidase activity. In recent years, CO, BV, and BR have been shown to control cellular processes such as inflammation, apoptosis, and antioxidant defense. This review covers our current knowledge about how heme induced endoplasmic reticulum stress (HIERS) participates in the pathogenesis of vascular disorders and highlights recent discoveries in the molecular mechanisms of HO-mediated cytoprotection in heme stress and ER stress, as well as crosstalk between ER stress and HO-1. Furthermore, we focus on the translational potential of HIERS and heme oxygenase-1 (HO-1) in atherosclerosis, diabetes mellitus, and brain hemorrhage.


Assuntos
Estresse do Retículo Endoplasmático , Heme Oxigenase (Desciclizante)/metabolismo , Heme/metabolismo , Doenças Vasculares/etiologia , Doenças Vasculares/metabolismo , Animais , Biomarcadores , Suscetibilidade a Doenças , Regulação da Expressão Gênica , Humanos , Especificidade de Órgãos , Estresse Oxidativo , Transdução de Sinais
11.
Front Physiol ; 10: 1584, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32009983

RESUMO

Vascular calcification is a life-threatening clinical condition in chronic kidney disease (CKD) and is associated with reduced zinc serum levels. Anemia is another frequent complication of CKD. Hypoxia-inducible factor (HIF) stabilizers, also known as HIF prolyl hydroxylase inhibitors (PHI), are promising candidates to treat CKD-associated anemia by increasing erythropoietin synthesis. Recent evidence suggests that HIFs play a pivotal role in vascular calcification. Our study explored feasible impacts of HIF PHI on phosphate (Pi)-induced calcification of vascular smooth muscle cells (VSMCs) and tested whether zinc might inhibit this mineralization process. Treatment of VSMCs with PHI aggravated Pi-induced calcium deposition and Pi uptake. PHI promoted Pi-induced loss of smooth muscle cell markers (ACTA-2, MYH11, SM22α) and enhanced osteochondrogenic gene expression (Msx-2, BMP-2, Sp7) triggering osteochondrogenic phenotypic switch of VSMCs. These effects of PHI paralleled with increased pyruvate dehydrogenase kinase 4 (PDK4) expression, decreased Runx2 Ser451 phosphorylation, and reduced cell viability. Zinc inhibited Pi-induced mineralization of VSMCs in a dose-dependent manner and also attenuated the pro-calcification effect of PHI in Pi-induced mineralization. Zinc inhibited osteochondrogenic phenotypic switch of VSMCs reflected by lowering Pi uptake, decreasing the expressions of Msx-2, BMP-2, and Sp7 as well as the loss of smooth muscle cell-specific markers. Zinc preserved phosphorylation state of Runx2 Ser451, decreased PDK4 level, and restored cell viability. PHI alone reduced the expression of smooth muscle markers without inducing mineralization, which was also inhibited by zinc. In addition, we observed a significantly lower serum zinc level in CKD as well as in patients undergoing carotid endarterectomy compared to healthy individuals. Conclusion - PHI promoted the loss of smooth muscle markers and augmented Pi-induced osteochondrogenic phenotypic switch leading to VSMCs calcification. This mineralization process was attenuated by zinc. Enhanced vascular calcification is a potential risk factor during PHI therapy in CKD which necessitates the strict follow up of vascular calcification and zinc supplementation.

12.
Front Physiol ; 9: 1595, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30515102

RESUMO

Accumulation of damaged or misfolded proteins resulted from oxidative protein modification induces endoplasmic reticulum (ER) stress by activating the pathways of unfolded protein response. In pathologic hemolytic conditions, extracellular free hemoglobin is submitted to rapid oxidation causing heme release. Resident cells of atherosclerotic lesions, after intraplaque hemorrhage, are exposed to heme leading to oxidative injury. Therefore, we raised the question whether heme can also provoke ER stress. Smooth muscle cells are one of the key players of atherogenesis; thus, human aortic smooth muscle cells (HAoSMCs) were selected as a model cell to reveal the possible link between heme and ER stress. Using immunoblotting, quantitative polymerase chain reaction and immunocytochemistry, we quantitated the markers of ER stress. These were: phosphorylated eIF2α, Activating transcription factor-4 (ATF4), DNA-damage-inducible transcript 3 (also known as C/EBP homology protein, termed CHOP), X-box binding protein-1 (XBP1), Activating transcription factor-6 (ATF6), GRP78 (glucose-regulated protein, 78kDa) and heme responsive genes heme oxygenase-1 and ferritin. In addition, immunohistochemistry was performed on human carotid artery specimens from patients who had undergone carotid endarterectomy. We demonstrate that heme increases the phosphorylation of eiF2α in HAoSMCs and the expression of ATF4. Heme also enhances the splicing of XBP1 and the proteolytic cleavage of ATF6. Consequently, there is up-regulation of target genes increasing both mRNA and protein levels of CHOP and GRP78. However, TGFß and collagen type I decreased. When the heme binding proteins, alpha-1-microglobulin (A1M) and hemopexin (Hpx) are present in cell media, the ER stress provoked by heme is inhibited. ER stress pathways are also retarded by the antioxidant N-acetyl cysteine (NAC) indicating that reactive oxygen species are involved in heme-induced ER stress. Consistent with these findings, elevated expression of the ER stress marker GRP78 and CHOP were observed in smooth muscle cells of complicated lesions with hemorrhage compared to either atheromas or healthy arteries. In conclusion, heme triggers ER stress in a time- and dose-dependent manner in HAoSMCs. A1M and Hpx as well as NAC effectively hamper heme-induced ER stress, supporting their use as a potential therapeutic approach to reverse such a deleterious effects of heme toxicity.

13.
Acta Microbiol Immunol Hung ; 63(4): 475-489, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28033726

RESUMO

Siderophores are produced by a number of microbes to capture iron with outstandingly high affinity, which property also generates biomedical and industrial interests. Desferrioxamine E (DFO-E) secreted by streptomycetes bacteria can be an ideal candidate for iron chelation therapy, which necessitates its cost-effective production for in vitro and animal studies. This study focused on the optimization of DFO-E production by Streptomyces parvulus CBS548.68. Different combinations of various carbon and nitrogen sources as well as the addition of 3-morpholinopropane-1-sulfonic acid (MOPS) markedly affected DFO-E yields, which were attributed, at least in part, to the higher biomass productions found in MOPS-supplemented cultures. In MOPS-supplemented glucose and sodium glutamate medium, DFO-E productions as high as 2,009 ± 90 mg/l of culture medium were reached. High-performance liquid chromatography analysis demonstrated that a simple two-step purification process yielded DFO-E preparations with purities of ∼97%. Matrix assisted laser desorption ionization-time of flight mass spectrometry analysis showed that purified DFO-E always contained traces of desferrioxamine D2.


Assuntos
Ácidos Hidroxâmicos/metabolismo , Lactamas/metabolismo , Streptomyces/metabolismo , Cromatografia Líquida de Alta Pressão , Meios de Cultura/química , Meios de Cultura/metabolismo , Ácidos Hidroxâmicos/análise , Ácidos Hidroxâmicos/isolamento & purificação , Microbiologia Industrial , Lactamas/análise , Lactamas/isolamento & purificação , Streptomyces/química
14.
Emerg Microbes Infect ; 5(11): e114, 2016 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-27826143

RESUMO

PAF, a small antifungal protein from Penicillium chrysogenum, inhibits the growth of several pathogenic filamentous fungi, including members of the Aspergillus genus. PAF has been proven to have no toxic effects in vivo in mice by intranasal application. To test its efficacy against invasive pulmonary aspergillosis (IPA), experiments were carried out in mice suffering from IPA. Adult mice were immunosuppressed and then infected with Aspergillus fumigatus. After stable infection, the animals were inoculated with PAF intranasally at a concentration of 2.7 mg/kg twice per day. At this concentration-which is highly toxic in vitro to A. fumigatus-the mortality of the animals was slightly delayed but finally all animals died. Histological examinations revealed massive fungal infections in the lungs of both PAF-treated and untreated animal groups. Because intranasally administered PAF was unable to overcome IPA, modified and combined therapies were introduced. The intraperitoneal application of PAF in animals with IPA prolonged the survival of the animals only 1 day. Similar results were obtained with amphotericin B (AMB), with PAF and AMB being equally effective. Combined therapy with AMB and PAF-which are synergistic in vitro-was found to be more effective than either AMB or PAF treatment alone. As no toxic effects of PAF in mammals have been described thus far, and, moreover, there are so far no A. fumigatus strains with reported inherent or acquired PAF resistance, it is worth carrying out further studies to introduce PAF as a potential antifungal drug in human therapy.


Assuntos
Antifúngicos/uso terapêutico , Aspergillus fumigatus/efeitos dos fármacos , Proteínas Fúngicas/uso terapêutico , Aspergilose Pulmonar Invasiva/tratamento farmacológico , Penicillium chrysogenum/química , Administração Intranasal , Anfotericina B/uso terapêutico , Animais , Antifúngicos/química , Antifúngicos/farmacologia , Antifúngicos/toxicidade , Aspergillus fumigatus/crescimento & desenvolvimento , Modelos Animais de Doenças , Quimioterapia Combinada , Humanos , Hospedeiro Imunocomprometido , Camundongos
15.
Pathol Oncol Res ; 20(4): 923-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24710824

RESUMO

Occurrence of genetic and epigenetic alterations affecting p14ARF and p16INK4A were investigated in tumour samples of 37 oral (OSCC) and 28 laryngeal squamous cell cancer (LSCC) patients, and compared to exfoliated buccal epithelial cells of 68 healthy controls. Presence of deletions and mutations/polymorphisms affecting exons were examined using sequencing. Methylation status of promoters was assessed by methylation-specific PCR. Chi-square and Fisher's exact tests were used to compare frequency of events. Exon deletions were found in four controls, one OSCC and 22 LSCC patients; the latter significantly differed from controls (p < 0.001). Only two mutations (T24610A and C24702A) were in p16 exon 1 of two OSCC patients. Polymorphisms G28575A (Ala140Thr), G31292C (C540G) and G28608A were found in both patient groups. The p14 promoter was unmethylated in 86.7 % of OSCC and in 85.7 % of LSCC patients; for the p16 promoter these rates were 69.0 % and 76.2 % for OSCC and LSCC patients, respectively. Combining the two patient groups, unmethylated promoter was significantly less frequent in case of both p14 and p16 (p = 0.043 and p = 0.001, respectively) compared to the control group. In summary, exon deletion may be important in LSCC, while promoter methylation was relatively frequent in both patient groups.


Assuntos
Carcinoma de Células Escamosas/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Epigênese Genética/genética , Deleção de Genes , Neoplasias Laríngeas/genética , Neoplasias Bucais/genética , Proteína Supressora de Tumor p14ARF/genética , Adulto , Idoso , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/mortalidade , Estudos de Casos e Controles , Metilação de DNA , Feminino , Seguimentos , Inativação Gênica , Humanos , Hungria/epidemiologia , Neoplasias Laríngeas/epidemiologia , Neoplasias Laríngeas/mortalidade , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/epidemiologia , Neoplasias Bucais/mortalidade , Mutação/genética , Prognóstico , Regiões Promotoras Genéticas/genética , Taxa de Sobrevida
16.
Med Microbiol Immunol ; 202(5): 353-63, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23649705

RESUMO

This study aimed to compare complete genome sequences of human papillomavirus (HPV) type 11 from two solitary papillomas (considered minimally aggressive), two moderately (six and nine episodes) and two highly aggressive (30 and 33 episodes) juvenile-onset respiratory papillomatoses. Genomic regions were sequenced using the Sanger method; sequences were compared to available GenBank genomes. Activity of the long control region (LCR) was assessed in HEp-2 cell line using luciferase assays and compared to that of the reference (GenBank Accession Number M14119). Site-directed mutagenesis was performed to confirm the association of polymorphisms with differences in LCR activity. Eleven alterations resulted in amino acid changes in different open reading frames. A72E in E1 and Q86K in E2 proteins were exclusively present in a moderately aggressive disease, L1 alterations A476V and S486F were unique to a severe papillomatosis. HPV11s in both solitary papillomas had identical LCRs containing a T7546C polymorphism, which strongly attenuated LCR activity, as confirmed by site-directed mutagenesis. This strong attenuator polymorphism was also present in the other four genomes showing significantly higher activities, but in these other alterations with demonstrable but statistically not significant attenuating (A7413C, 7509 T deletion) or enhancing (C7479T, T7904A) effect on transactivating potential (as demonstrated by site-directed mutagenesis) were also detected. LCR activities corresponded well to severity, excepting the highly aggressive papillomatosis with the L1 alterations. Presence of intratypic variants cannot explain differences in severity of respiratory papillomatoses associated with HPV11; virulence seems to be determined by the interaction of multiple genetic differences.


Assuntos
Genoma Viral , Papillomavirus Humano 11/genética , Papillomavirus Humano 11/patogenicidade , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , Polimorfismo Genético , Infecções Respiratórias/patologia , Infecções Respiratórias/virologia , Criança , Pré-Escolar , Feminino , Papillomavirus Humano 11/isolamento & purificação , Humanos , Lactente , Mutagênese Sítio-Dirigida , Mutação , Análise de Sequência de DNA , Virulência
17.
PLoS One ; 8(4): e61507, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23646108

RESUMO

Changes in intracellular calcium concentration ([Ca²âº]i) as well as in the phosphorylation state of proteins have been implicated in keratinocyte wound healing revealed in scratch assays. Scratching confluent HaCaT monolayers decreased the number of cells displaying repetitive Ca²âº oscillations as well as the frequency of their Ca²âº-transients in cells close to the wounded area and initiated migration of the cells into the wound bed. In contrast, calyculin-A (CLA) and okadaic acid (OA), known cell permeable inhibitors of protein phosphatase-1 and 2A, increased the level of resting [Ca²âº]i and suppressed cell migration and wound healing of HaCaT cells. Furthermore, neither CLA nor OA influenced how scratching affected Ca²âº oscillations. It is assumed that changes in and alterations of the phosphorylation level of Ca²âº-transport and contractile proteins upon phosphatase inhibition mediates cell migration and wound healing.


Assuntos
Sinalização do Cálcio , Inibidores Enzimáticos/farmacologia , Homeostase/efeitos dos fármacos , Queratinócitos/efeitos dos fármacos , Queratinócitos/fisiologia , Fosfoproteínas Fosfatases/antagonistas & inibidores , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Toxinas Marinhas , Ácido Okadáico/farmacologia , Oxazóis/farmacologia
18.
Toxicol Appl Pharmacol ; 269(1): 8-16, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23466426

RESUMO

The antifungal protein of Penicillium chrysogenum (PAF) inhibits the growth of important pathogenic filamentous fungi, including members of the Aspergillus family and some dermatophytes. Furthermore, PAF was proven to have no toxic effects on mammalian cells in vitro. To prove that PAF could be safely used in therapy, experiments were carried out to investigate its in vivo effects. Adult mice were inoculated with PAF intranasally in different concentrations, up to 2700 µg·kg⁻¹ daily, for 2 weeks. Even at the highest concentration--a concentration highly toxic in vitro for all affected molds used, animals neither died due to the treatment nor were any side effects observed. Histological examinations did not find pathological reactions in the liver, in the kidney, and in the lungs. Mass spectrometry confirmed that a measurable amount of PAF was accumulated in the lungs after the treatment. Lung tissue extracts from PAF treated mice exerted significant antifungal activity. Small-animal positron emission tomography revealed that neither the application of physiological saline nor that of PAF induced any inflammation while the positive control lipopolysaccharide did. The effect of the drug on the skin was examined in an irritative dermatitis model where the change in the thickness of the ears following PAF application was found to be the same as in control and significantly less than when treated with phorbol-12-myristate-13-acetate used as positive control. Since no toxic effects of PAF were found in intranasal application, our result is the first step for introducing PAF as potential antifungal drug in therapy.


Assuntos
Antifúngicos/administração & dosagem , Proteínas Fúngicas/administração & dosagem , Penicillium chrysogenum/metabolismo , Administração por Inalação , Animais , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antifúngicos/metabolismo , Antifúngicos/toxicidade , Relação Dose-Resposta a Droga , Feminino , Proteínas Fúngicas/química , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/toxicidade , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Pulmão/diagnóstico por imagem , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Masculino , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos C57BL , Peso Molecular , Tomografia por Emissão de Pósitrons , Medição de Risco , Pele/efeitos dos fármacos , Fatores de Tempo , Testes de Toxicidade
19.
Acta Microbiol Immunol Hung ; 58(4): 319-37, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22207290

RESUMO

Diversity of TTV1 was assessed in the head and neck region in patients with potentially malignant (oral lichen planus, oral leukoplakia) and malignant lesions (oral and laryngeal squamous cell cancers) and was compared to that found in the uterine cervix (cervical atypia and cervical cancer) by directly sequencing the NG061-063 segment of ORF1. These sequences were classified by the formerly used genogroup-genotype system as well as by the newly accepted species classification by aligning with the corresponding region of the type sequences of the 29 TTV species. All sequences obtained during the study clustered together with the TTV1 type sequence; to express diversity within TTV1, genotypes and subtypes of the former classification were used.The commonest subtypes were 2c followed by 2b, 1a and 1b. Subtypes 2b and 2c were evenly distributed among cervical samples; subtype 1a was more frequent in patients with cervical atypia or cancer. Subtypes 2c was more frequent than 2b in head and neck lesions. In conclusion, genotype and even subtype distribution may be important in association with diseases, therefore using this classification for characterization of intraspecies diversity of TTV1 is proposed.


Assuntos
Mucosa/virologia , Torque teno virus/classificação , Feminino , Variação Genética , Genótipo , Neoplasias de Cabeça e Pescoço/virologia , Humanos , Leucoplasia Oral/virologia , Líquen Plano/virologia , Neoplasias de Células Escamosas/virologia , Filogenia , Torque teno virus/genética , Neoplasias do Colo do Útero/virologia
20.
Antiviral Res ; 92(2): 356-8, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21945249

RESUMO

Five sequential human papillomavirus type 11 (HPV11) positive samples collected from an aggressive juvenile onset recurrent respiratory papillomatosis before, during and after intralesional cidofovir therapy leading to virological failure after initial response were analyzed. Sequencing of the complete genome as well as methylation analysis by bisulfate modification and sequencing of the long control region (LCR) were performed to seek for genetic and epigenetic changes as a possible background for therapy failure. Single-strand conformation polymorphism of E1, E2, E6, E7 and LCR was used to exclude the presence of multiple HPV11 infection. All five complete genomes were identical and all four E2 binding sites in the LCR were uniformly unmethylated in all five genomes. Thus the virological failure was not due to virological factors suggesting that cidofovir action may depend more heavily on the host.


Assuntos
Antivirais/administração & dosagem , Citosina/análogos & derivados , Genoma Viral , Papillomavirus Humano 11/genética , Organofosfonatos/administração & dosagem , Infecções por Papillomavirus/tratamento farmacológico , Infecções por Papillomavirus/virologia , Infecções Respiratórias/tratamento farmacológico , Infecções Respiratórias/virologia , Cidofovir , Citosina/administração & dosagem , Metilação de DNA , DNA Viral/química , DNA Viral/genética , Epigênese Genética , Papillomavirus Humano 11/isolamento & purificação , Humanos , Dados de Sequência Molecular , Mutação , Polimorfismo Conformacional de Fita Simples , Análise de Sequência de DNA , Falha de Tratamento
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