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1.
Int J Mol Sci ; 23(24)2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-36555325

RESUMO

Insects vastly outnumber us in terms of species and total biomass, and are among the most efficient and voracious consumers of plants on the planet. As a result, to preserve crops, one of the primary tasks in agriculture has always been the need to control and reduce the number of insect pests. The current use of chemical insecticides leads to the accumulation of xenobiotics in ecosystems and a decreased number of species in those ecosystems, including insects. Sustainable development of human society is impossible without useful insects, so the control of insect pests must be effective and selective at the same time. In this article, we show for the first time a natural way to regulate the number of insect pests based on the use of extracellular double-stranded DNA secreted by the plant Pittosporum tobira. Using a principle similar to one found in nature, we show that the topical application of artificially synthesized short antisense oligonucleotide insecticides (olinscides, DNA insecticides) is an effective and selective way to control the insect Coccus hesperidum. Using contact oligonucleotide insecticide Coccus-11 at a concentration of 100 ng/µL on C. hesperidum larvae resulted in a mortality of 95.59 ± 1.63% within 12 days. Green oligonucleotide insecticides, created by nature and later discovered by humans, demonstrate a new method to control insect pests that is beneficial and safe for macromolecular insect pest management.


Assuntos
Hemípteros , Inseticidas , Animais , Humanos , Inseticidas/farmacologia , Oligonucleotídeos/farmacologia , Ecossistema , Resistência a Inseticidas , Insetos/genética , Controle de Insetos/métodos , Hemípteros/genética , Agricultura/métodos , Produtos Agrícolas/genética , DNA/farmacologia , Controle Biológico de Vetores
2.
Blood ; 130(8): 1031-1040, 2017 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-28634183

RESUMO

Band 3 (also known as the anion exchanger, SLCA1, AE1) constitutes the major attachment site of the spectrin-based cytoskeleton to the erythrocyte's lipid bilayer and thereby contributes critically to the stability of the red cell membrane. During the intraerythrocytic stage of Plasmodium falciparum's lifecycle, band 3 becomes tyrosine phosphorylated in response to oxidative stress, leading to a decrease in its affinity for the spectrin/actin cytoskeleton and causing global membrane destabilization. Because this membrane weakening is hypothesized to facilitate parasite egress and the consequent dissemination of released merozoites throughout the bloodstream, we decided to explore which tyrosine kinase inhibitors might block the kinase-induced membrane destabilization. We demonstrate here that multiple Syk kinase inhibitors both prevent parasite-induced band 3 tyrosine phosphorylation and inhibit parasite-promoted membrane destabilization. We also show that the same Syk kinase inhibitors suppress merozoite egress near the end of the parasite's intraerythrocytic lifecycle. Because the entrapped merozoites die when prevented from escaping their host erythrocytes and because some Syk inhibitors have displayed long-term safety in human clinical trials, we suggest Syk kinase inhibitors constitute a promising class of antimalarial drugs that can suppress parasitemia by inhibiting a host target that cannot be mutated by the parasite to evolve drug resistance.


Assuntos
Membrana Eritrocítica/metabolismo , Membrana Eritrocítica/parasitologia , Parasitos/crescimento & desenvolvimento , Plasmodium falciparum/crescimento & desenvolvimento , Inibidores de Proteínas Quinases/farmacologia , Quinase Syk/antagonistas & inibidores , Adulto , Animais , Proteína 1 de Troca de Ânion do Eritrócito/metabolismo , Diferenciação Celular/efeitos dos fármacos , Membrana Eritrocítica/efeitos dos fármacos , Membrana Eritrocítica/ultraestrutura , Feminino , Humanos , Concentração Inibidora 50 , Malária Falciparum , Masculino , Parasitos/efeitos dos fármacos , Parasitos/ultraestrutura , Fosforilação/efeitos dos fármacos , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/ultraestrutura , Quinase Syk/metabolismo
3.
Reprod Biol Endocrinol ; 15(1): 47, 2017 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-28645283

RESUMO

BACKGROUND: The complex relationship between oocyte morphology, specific follicular fluid metabolites, gene expression in cumulus granulosa cells, and oocyte competence toward fertilization and embryo development still needs further clarification. METHODS: Forty-six oocytes retrieved from the largest pre-ovulatory follicle of patients undergoing intra-cytoplasmic sperm injection (ICSI) were considered assessing: (a) oocyte morphological characteristics at polarized light microscopy (PLM), (b) specific follicular fluid (FF) metabolites previously suggested to influence oocyte competence (AMH, markers of redox status and of cytotoxicity), (c) transcription of AMH and AMH type II receptor genes in cumulus cells. Data were analyzed using mono-parametric tests and multivariable logistic analysis in order to correlate morphological and biochemical data with fertilization. RESULTS: Comparing normally fertilized oocytes (n = 29, F group) with unfertilized (n = 17, nF group) we observed that: (a) the meiotic spindle area and major axis were significantly higher in nF group and in fertilized oocytes undergoing an early embryo development arrest; (b) AMH level in FF was comparable in F and nF groups; (c) the FF of nF group contained significantly higher levels of cytotoxicity (lactate dehydrogenase) and oxidative stress (Cu,Zn-superoxide dismutase, catalase, 4-hydroxynonenal-protein conjugates) markers; (d) cumulus cells of nF group showed significantly higher AMH receptor type II gene expression. CONCLUSIONS: Taken together, these observations suggest that an excessive cytotoxicity level can alter AMH signal transduction within cumulus cells, in turn leading to partial inhibition of aromatase activity, altered cytoplasmic maturation and increased oxidative stress, factors able to impair oocyte fertilization competence and embryo growth.


Assuntos
Células do Cúmulo/metabolismo , Fertilização , Líquido Folicular/metabolismo , Expressão Gênica , Oócitos/citologia , Injeções de Esperma Intracitoplásmicas/métodos , Adulto , Hormônio Antimülleriano/genética , Hormônio Antimülleriano/metabolismo , Desenvolvimento Embrionário , Feminino , Humanos , Microscopia de Polarização/métodos , Recuperação de Oócitos/métodos , Receptores de Peptídeos/genética , Receptores de Peptídeos/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/genética , Receptores de Fatores de Crescimento Transformadores beta/metabolismo
4.
Int J Mol Sci ; 18(11)2017 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-29149051

RESUMO

Baculovirus IAP (inhibitor-of-apoptosis) genes originated by capture of host genes. Unmodified short antisense DNA oligonucleotides (oligoDNAs) from baculovirus IAP genes can down-regulate specific gene expression profiles in both baculovirus-free and baculovirus-infected insects. In this study, gypsy moth (Lymantria dispar) larvae infected with multiple nucleopolyhedrovirus (LdMNPV), and LdMNPV-free larvae, were treated with oligoDNA antisense to the RING (really interesting new gene) domain of the LdMNPV IAP-3 gene. The results with respect to insect mortality, biomass accumulation, histological studies, RT-PCR, and analysis of DNA apoptotic fragmentation suggest that oligoRING induced increased apoptotic processes in both LdMNPV-free and LdMNPV-infected insect cells, but were more pronounced in the latter. These data open up possibilities for promising new routes of insect pest control using antisense phosphodiester DNA oligonucleotides.


Assuntos
Controle de Insetos/métodos , Mariposas/virologia , Nucleopoliedrovírus/genética , Oligodesoxirribonucleotídeos Antissenso , Animais , Apoptose , Genes Virais/genética , Larva/virologia , Transcriptoma , Proteínas Virais/genética
5.
Pestic Biochem Physiol ; 131: 32-9, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27265824

RESUMO

Numerous studies suggest a cellular origin for the Lymantria dispar multicapsid nuclear polyhedrosis virus (LdMNPV) anti-apoptosis genes IAPs, thus opening a possibility to use the fragments of these genes for modulation of host metabolism. We report here the strong insecticidal and metabolic effect of single-stranded antisense DNA fragment from RING (really interesting new gene) domain of gypsy moth LdMNPV IAP-3 gene: specifically, on reduction of biomass (by 35%) and survival of L. dispar caterpillars. The treatment with this DNA fragment leads to a significantly higher mortality rates of female insects (1.7 fold) accompanied with the signs of apoptosis. Additionally, we show increased expression of host IAP-1, caspase-4 and gelsolin genes in eggs laid by survived females treated with RING DNA fragment accompanied with calcium and magnesium imbalance, indicating that the strong stress reactions and metabolic effects are not confined to treated insects but likely led to apoptosis in eggs too. The proposed new approach for insect pest management, which can be considered as advancement of "microbial pesticides", is based on the application of the specific virus DNA, exploiting the knowledge about virus-pest interactions and putting it to the benefit of mankind.


Assuntos
Genes Virais/genética , Inseticidas , Mariposas , Nucleopoliedrovírus/genética , Animais , Apoptose/genética , Feminino , Controle de Insetos/métodos , Larva , Masculino , Reação em Cadeia da Polimerase em Tempo Real
7.
Br J Haematol ; 164(3): 438-50, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24422726

RESUMO

Converging in vitro evidence and clinical data indicate that oxidative stress may play important roles in Plasmodium falciparum malaria, notably in the pathogenesis of severe anaemia. However, oxidative modifications of the red blood cell (RBC)-membrane by 4-hydroxynonenal (4-HNE) and haemoglobin-binding, previously hypothesized to contribute mechanistically to the pathogenesis of clinical malaria, have not yet been tested for clinical significance. In 349 non-immune Mozambican newborns recruited in a double-blind placebo-controlled chemoprophylaxis trial, oxidative markers including 4-HNE-conjugates and membrane-bound haemoglobin were longitudinally assessed from 2·5 to 24 months of age, at first acute malaria episode and in convalescence. During acute malaria, 4-HNE-conjugates were shown to increase significantly in parasitized and non-parasitized RBCs. In parallel, advanced oxidation protein products (AOPP) rose in plasma. 4-HNE-conjugates correlated with AOPP and established plasma but not with RBC oxidative markers. High individual levels of 4-HNE-conjugates were predictive for increased malaria incidence rates in children until 2 years of life and elevated 4-HNE-conjugates in convalescence accompanied sustained anaemia after a malaria episode, indicating 4-HNE-conjugates as a novel patho-mechanistic factor in malaria. A second oxidative marker, haemoglobin binding to RBC-membranes, hypothesized to induce clearing of RBCs from circulation, was predictive for lower malaria incidence rates. Further studies will show whether or not higher membrane-haemoglobin values at the first malaria episode may provide protection against malaria.


Assuntos
Anemia/sangue , Anemia/microbiologia , Eritrócitos/metabolismo , Eritrócitos/parasitologia , Malária Falciparum/sangue , Estresse Oxidativo/fisiologia , Aldeídos/sangue , Anemia/imunologia , Antígenos de Protozoários/imunologia , Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , Biomarcadores/sangue , Pré-Escolar , Método Duplo-Cego , Doenças Endêmicas , Eritrócitos/imunologia , Humanos , Lactente , Malária Falciparum/epidemiologia , Malária Falciparum/imunologia , Malária Falciparum/prevenção & controle , Moçambique/epidemiologia , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêutico
8.
Malar J ; 13: 134, 2014 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-24693973

RESUMO

BACKGROUND: Advanced oxidation protein products (AOPP) are newly identified efficient oxidative stress biomarkers. In a longitudinal birth cohort the effects were investigated of genetic polymorphisms in five oxidative pathway genes on AOPP levels. METHODS: This study is part of a three-arm randomized, double-blind, placebo-controlled trial. Three hundred and twelve children were included in the present study with AOPP levels measured at 2.5, 5.5, 10.5, 15 and 24 months of age. Twelve polymorphisms were genotyped in five oxidative stress pathway genes: glutathione reductase (GSR), glutamylcysteine synthetase (GCLC), glutathione S-transferase (GST) P1, haem oxygenase 1 (HMOX1) and superoxide dismutase 2 (SOD2) in 298 children. There were 284 children assessed for anaemia and clinical malaria infection at the age of 24 months. RESULTS: Two principal components (PCA1 and PCA2) were derived from the AOPP levels measured at the five time points. PCA1 was significantly associated with anaemia (p = 0.0002), and PCA2 with clinical malaria infection (p = 0.047). In the K-Means Cluster Analysis based on levels of AOPP, children were clustered into two groups: Group A (lower AOPP levels) and Group B (higher AOPP levels). The cluster membership was significantly associated with anaemia (p =0.003) as well as with the GSR RS3594 polymorphism (p = 0.037). Mixed linear regression analyses found that the single nucleotide polymorphisms GCLC RS10948751 and HMOX1 RS17885925 were significantly associated with AOPP levels (p = 0.030 and p = 0.027, respectively). CONCLUSION: Plasma AOPP levels were predictive for anaemia and oxidative stress markers for clinical malaria infection in two year old children. Several polymorphisms in GCLC, GSR and HMOX1 genes were associated with oxidative stress status of these children.


Assuntos
Produtos da Oxidação Avançada de Proteínas/genética , Anemia/fisiopatologia , Malária Falciparum/fisiopatologia , Estresse Oxidativo , Polimorfismo Genético , Produtos da Oxidação Avançada de Proteínas/sangue , Anemia/parasitologia , Pré-Escolar , Método Duplo-Cego , Feminino , Humanos , Lactente , Estudos Longitudinais , Malária Falciparum/complicações , Malária Falciparum/parasitologia , Masculino , Moçambique , Plasmodium falciparum/fisiologia
9.
Pestic Biochem Physiol ; 113: 1-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25052520

RESUMO

This paper focuses on the DNA insecticides as a novel preparation against gypsy moth (Lymantria dispar) based on DNA fragments of the anti-apoptotic gene of its nuclear polyhedrosis virus. It was found that the external application of a solution with two single-stranded DNA fragments from BIR and RING domains of LdMNPV (L.dispar multicapsid nuclear polyhedrosis virus) IAP-3 (inhibitor of apoptosis) gene induces a significantly higher mortality of gypsy moth caterpillars in comparison with the application of the control solutions. This effect does not depend on the infection of caterpillars with LdMNPV. The results also show that DNA insecticides based on LdMNPV IAP-3 gene fragments can be selective in action, and at least are not harmful to tobacco hornworm (Manduca sexta) and black cutworm (Agrotis ipsilon). Part of the gypsy moth genome cloned with the fragments of BIR and RING domains of LdMNPV IAP-3 gene as primers, has an overlap with the corresponding part of the LdMNPV IAP-3 gene and L.dispar IAP-1 mRNA for an inhibitor of apoptosis protein with the high cover by query, allows assuming that we cloned a part of gypsy moth anti-apoptosis gene. This finding gives the grounding that proposed here DNA insecticides might act through the blocking of the mechanisms involved in post transcriptional expression of insect anti-apoptosis genes. The results show the insecticidal potential of the viral genome fragments that can be used to create safe and relatively fast-acting DNA insecticides to control the quantity of gypsy moth populations, important task for forestry and agriculture.


Assuntos
DNA de Cadeia Simples/farmacologia , Inseticidas/farmacologia , Mariposas/efeitos dos fármacos , Nucleopoliedrovírus/genética , Animais , DNA de Cadeia Simples/química , Inseticidas/química
10.
Blood ; 117(21): 5674-82, 2011 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-21460246

RESUMO

Natural hemozoin (nHZ), prepared after schizogony, consists of crystalline ferriprotoporphyrin-IX dimers from undigested heme bound to host and parasite proteins and lipids. Phagocytosed nHZ alters important functions of host phagocytes. Most alterations are long-term effects. We show that host fibrinogen (FG) was constantly present (at ~ 1 FG per 25 000 HZ-heme molecules) and stably bound to nHZ from plasma-cultured parasites. FG was responsible for the rapid 100-fold stimulation of reactive oxygen species production and 50-fold increase of TNF and monocyte chemotactic protein 1 by human monocytes. Those effects, starting within minutes after nHZ cell contact, were because of interaction of FG with FG-receptors TLR4 and integrin CD11b/CD18. Receptor blockage by specific mAbs or removal of FG from nHZ abrogated the effects. nHZ-opsonizing IgGs contribute to the stimulatory response but are not essential for FG effects. Immediate increase in reactive oxygen species and TNF may switch on previously described long-term effects of nHZ, largely because of HZ-generated lipo-peroxidation products 15(S,R)-hydroxy-6,8,11,13-eicosatetraenoic acid and 4-hydroxynonenal. The FG/HZ effects mediated by TLR4/integrins represent a novel paradigm of nHZ activity and allow expansion of nHZ effects to nonphagocytic cells, such as endothelia and airway epithelia, and lead to a better understanding of organ pathology in malaria.


Assuntos
Antígeno CD11b/metabolismo , Antígenos CD18/metabolismo , Fibrinogênio/metabolismo , Hemeproteínas/metabolismo , Integrinas/metabolismo , Monócitos/metabolismo , Receptor 4 Toll-Like/metabolismo , Western Blotting , Células Cultivadas , Humanos , Malária Falciparum/metabolismo , Malária Falciparum/parasitologia , Monócitos/parasitologia , Fagocitose , Plasmodium falciparum , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
11.
Br J Haematol ; 157(1): 116-24, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22352722

RESUMO

Severe anaemia is a life-threatening complication of falciparum malaria associated with loss of predominantly non-parasitized red blood cells (npRBCs). This poorly elucidated process might be influenced by (i) rosettes, i.e. npRBCs cytoadherent to haemozoin-containing parasitized RBCs (pRBCs) and (ii) generation in pRBCs of 4-hydroxynonenal (4-HNE) through haemozoin-catalysed lipid peroxidation. We explored whether close proximity in rosettes may facilitate 4-HNE transfer to npRBCs, which is likely to enhance their phagocytosis and contribute to malaria anaemia. Fluorescence microscopy and flow cytometry data indicated 4-HNE transfer to npRBCs in rosettes. Rosettes were formed by 64·8 ± 1·8% varO-expressing pRBCs, and 8·7 ± 1·1% npRBCs were positive for 4-HNE-protein-conjugates, while low-rosetting parasites generated only 2·4 ± 1·1% 4-HNE-conjugate-positive npRBCs. 4-HNE transfer decreased after blocking rosetting by monoclonal antibodies. A positive linear relationship between rosette frequency and 4-HNE-conjugates in npRBCs was found in 40 malaria patients, a first indication for a role of rosetting in npRBCs modifications in vivo. Children with severe malaria anaemia had significantly higher percentages of 4-HNE-conjugate-positive npRBCs compared to children with uncomplicated malaria. In conclusion, 4-HNE transfer from pRBCs to npRBCs in rosettes is suggested to play a role in the phagocytic removal of large numbers of npRBCs, the hallmark of severe malaria anaemia.


Assuntos
Aldeídos/metabolismo , Anemia/sangue , Anemia/parasitologia , Eritrócitos , Malária Falciparum/sangue , Plasmodium falciparum/metabolismo , Anemia/etiologia , Transporte Biológico , Linhagem Celular , Criança , Pré-Escolar , Eritrócitos/metabolismo , Eritrócitos/parasitologia , Feminino , Hemeproteínas/metabolismo , Humanos , Lactente , Peroxidação de Lipídeos , Malária Falciparum/complicações , Masculino
12.
Blood ; 116(20): 4328-37, 2010 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-20686121

RESUMO

Severe malaria anemia is characterized by inhibited/altered erythropoiesis and presence of hemozoin-(HZ)-laden bone-marrow macrophages. HZ mediates peroxidation of unsaturated fatty acids and production of bioactive aldehydes such as 4-hydroxynonenal (HNE). HZ-laden human monocytes inhibited growth of cocultivated human erythroid cells and produced HNE that diffused to adjacent cells generating HNE-protein adducts. Cocultivation with HZ or treatment with low micromolar HNE inhibited growth of erythroid cells interfering with cell cycle without apoptosis. After HZ/HNE treatment, 2 critical proteins in cell-cycle regulation, p53 and p21, were increased and the retinoblastoma protein, central regulator of G1-to-S-phase transition, was consequently hypophosphorylated, while GATA-1, master transcription factor in erythropoiesis was reduced. The resultant decreased expression of cyclin A and D2 retarded cell-cycle progression in erythroid cells and the K562 cell line. As a second major effect, HZ and HNE inhibited protein expression of crucial receptors (R): transferrinR1, stem cell factorR, interleukin-3R, and erythropoietinR. The reduced receptor expression and the impaired cell-cycle activity decreased the production of cells expressing glycophorin-A and hemoglobin. Present data confirm the inhibitory role of HZ, identify HNE as one HZ-generated inhibitory molecule and describe molecular targets of HNE in erythroid progenitors possibly involved in erythropoiesis inhibition in malaria anemia.


Assuntos
Aldeídos/farmacologia , Anemia/complicações , Anemia/fisiopatologia , Eritropoese/efeitos dos fármacos , Hemeproteínas/farmacologia , Malária/complicações , Malária/fisiopatologia , Anemia/patologia , Biomarcadores/metabolismo , Ciclo Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Técnicas de Cocultura , Ensaio de Unidades Formadoras de Colônias , Ciclina A/metabolismo , Ciclina D2/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Células Eritroides/efeitos dos fármacos , Células Eritroides/metabolismo , Células Eritroides/patologia , Fator de Transcrição GATA1/metabolismo , Glicoforinas/metabolismo , Hemoglobinas/metabolismo , Humanos , Malária/patologia , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Monócitos/patologia , Receptores Imunológicos/metabolismo , Proteína Supressora de Tumor p53/metabolismo
13.
Malar J ; 11: 428, 2012 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-23259636

RESUMO

BACKGROUND: Severe falciparum malaria anaemia (SMA) is a frequent cause of mortality in children and pregnant women. The most important determinant of SMA appears to be the loss of non-parasitized red blood cells (np-RBCs) in excess of loss of parasitized (p-) RBCs at schizogony. Based on data from acute SMA where excretion of haemoglobin in urine and increased plasma haemoglobin represented respectively less than 1% and 0.5% of total Hb loss, phagocytosis appears to be the predominant mechanism of removal of np- and p-RBC.Estimates indicate that np-RBCs are cleared in approximately 10-fold excess compared to p-RBCs. An even larger removal of np-RBCs has been described in vivax malaria anaemia. Estimates were based on two single studies both performed on neurosyphilitic patients who underwent malaria therapy. As the share of np-RBC removal is likely to vary between wide limits, it is important to assess the contribution of both np- and p-RBC populations to overall RBC loss, and disclose the mechanism of such variability. As available methods do not discriminate between the removal of np- vs p-RBCs, the purpose of this study was to set up a system allowing the simultaneous determination of phagocytosis of p- and np-RBC in the same sample. METHODS AND RESULTS: Phagocytosis of p- and np-RBCs was quantified in the same sample using double-labelled target cells and the human phagocytic cell-line THP-1, pre-activated by TNF and IFNγ to enhance their phagocytic activity. Target RBCs were double-labelled with fluorescent carboxyfluorescein-succinimidyl ester (CF-SE) and the DNA label ethidium bromide (EB). EB, a DNA label, allowed to discriminate p-RBCs that contain parasitic DNA from the np-RBCs devoid of DNA. FACS analysis of THP-1 cells fed with double-labelled RBCs showed that p- and np-RBCs were phagocytosed in different proportions in relation to parasitaemia. CONCLUSIONS: The assay allowed the analysis of phagocytosis rapidly and with low subjective error, and the differentiation between phagocytosed p- and np-RBCs in the same sample. The presented method may help to analyse the factors or conditions that modulate the share of np-RBC removal in vitro and in vivo and lead to a better understanding of the pathogenesis of SMA.


Assuntos
Eritrócitos/imunologia , Eritrócitos/parasitologia , Citometria de Fluxo/métodos , Malária Falciparum/imunologia , Malária Falciparum/parasitologia , Fagocitose , Plasmodium falciparum/imunologia , Adulto , Anemia/sangue , Anemia/etiologia , Anemia/parasitologia , Linhagem Celular , Criança , Etídio , Feminino , Fluoresceínas , Corantes Fluorescentes , Interações Hospedeiro-Parasita/imunologia , Humanos , Malária Falciparum/sangue , Malária Falciparum/complicações , Monócitos/imunologia , Monócitos/parasitologia , Plasmodium falciparum/crescimento & desenvolvimento , Gravidez , Complicações Parasitárias na Gravidez/sangue , Complicações Parasitárias na Gravidez/imunologia , Complicações Parasitárias na Gravidez/parasitologia
14.
J Ophthalmol ; 2019: 7231015, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31781380

RESUMO

The aim of this study was to assess the oxidative stress status in eyes affected by synchysis scintillans and to compare it to vitreoretinal disorders without synchysis scintillans. Human aqueous and vitreous humors were obtained during vitrectomy from thirty-seven otherwise healthy patients that were randomly chosen among patients that had to undergo a 25-gauge pars plana vitrectomy from the central vitreous cavity, for either synchysis scintillans (n = 16) or vitreoretinal disorders without synchysis scintillans (n = 21), such as idiopathic epimacular membrane (n = 12), macular hole (n = 5), or rhegmatogenous retinal detachment (n = 4). The redox parameters thiobarbituric acid reactive substances (TBARS), a measurement of lipid peroxidation, nitrite concentration, an estimate of nitric oxide (NO) production, 4-hydroxynonenal (4-HNE)-protein conjugates, a structural protein modification by lipid peroxidation product 4-HNE, and the antioxidative activities of Cu,Zn-superoxide dismutase (SOD), and catalase were measured in aqueous and vitreous humors and compared between synchysis scintillans affected and not-affected patients. TBARS and nitrite levels of the vitreous humor were significantly higher in patients with synchysis scintillans as compared to patients affected by vitreoretinal disorders without synchysis scintillans. Synchysis scintillans patients had significantly lower activities of SOD and catalase both in aqueous and vitreous humors than patients with vitreoretinal disorders without synchysis. The consequently higher lipoperoxide-dependent 4-HNE production in synchysis scintillans was detectable in aqueous and vitreous humors as a significant increased accumulation of 4-HNE-protein conjugates vs nonsynchysis vitreoretinal disorders. Additionally, hyaluronic acid (HA) was significantly decreased in the vitreous body of synchysis scintillans patients. The data consistently show that synchisis scintillans is accompanied by a redox imbalance with increased oxidative modifications of 4-HNE proteins and loss of HA, both of likely importance for remote damages of the retina. It remains to be proven whether a therapeutic strategy which targets oxidative stress may be effective in the treatment of synchysis patients.

15.
Int J Ophthalmol ; 11(7): 1145-1151, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30046531

RESUMO

AIM: To evaluate whether the Q-switched Nd:YAG laser treatment applied in routine capsulotomy elicits oxidative stress in aqueous and vitreous humors. METHODS: Thirty-six patients who had to undergo a 25 gauge pars plana vitrectomy due to vitreoretinal disorders were enrolled, 15 of them underwent a Q-switched Nd:YAG laser capsulotomy 7d before vitrectomy due to posterior capsule opacification (PCO) (Nd:YAG laser group) while the remaining 21 patients were not laser treated before vitrectomy (no Nd:YAG laser group). Samples of the aqueous and vitreous humors were collected during vitrectomy from all patients for the assessment of oxidative parameters which were compared between the Nd:YAG laser group and no Nd:YAG laser group. Thiobarbituric acid reactive substances (TBARS), a product of membrane lipid peroxidation, nitrite levels, the antioxidative activities of SOD and catalase, the 4-HNE-protein conjugate formation, indicating structural modifications in proteins due to lipoperoxidation, were assessed in aqueous and vitreous samples. RESULTS: In the human vitreous humor TBARS levels are significantly higher in the Nd:YAG laser group compared to the no Nd:YAG laser group and importantly, there is a significant correlation between the TBARS levels and the total energy of Nd:YAG laser used during capsulotomy. Moreover the anti-oxidative activities of SOD and catalase were significantly decreased by Nd:YAG laser treatment, both in aqueous and vitreous humors. In accordance with the TBARS data and anti-oxidative enzyme activities, significantly higher levels of proteins were conjugated with the lipoperoxidation product 4-HNE in the aqueous and vitreous humors in the Nd:YAG laser-treated group in comparison to no Nd:YAG laser group. CONCLUSION: These data, clearly suggest that any change that Q-switched Nd:YAG photo disruption may cause in the aqueous and vitreous compartments, resulting in a higher level of oxidative damage might be of considerable clinical significance particularly by accelerating the aging of the anterior and posterior segments of the eye and by worsening the intraocular pressure, the uveal, the retinal (especially macular) pathologies.

16.
Malar J ; 6: 73, 2007 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-17543124

RESUMO

BACKGROUND: Enhanced production of nitric oxide (NO) following upmodulation of the inducible isoform of NO synthase (iNOS) by haemozoin (HZ), inflammatory cytokines and LPS may provide protection against Plasmodium falciparum malaria by killing hepatic and blood forms of parasites and inhibiting the cytoadherence of parasitized erythrocytes (RBC) to endothelial cells. Monocytes and macrophages are considered to contribute importantly to protective upregulation of iNOS and production of NO. Data obtained with murine phagocytes fed with human HZ and synthetic HZ (sHZ) indicate that supplemental treatment of those cells with IFN-gamma elicited significant increases in protein and mRNA expression of iNOS and NO production, providing a potential mechanism linking HZ phagocytosis and increased production of NO. Purpose of this study was to analyse the effect of P. falciparum HZ and sHZ supplemental to treatment with IFN-gamma and/or a stimulatory cytokine-LPS mix on iNOS protein and mRNA expression in immuno-purified human monocytes. METHODS: Adherent immunopurified human monocytes (purity >85%), and murine phagocytic cell lines RAW 264.7, N11 and ANA1 were fed or not with P. falciparum HZ or sHZ and treated or not with IFN-gamma or a stimulatory cytokine-LPS mix. Production of NO was quantified in supernatants, iNOS protein and mRNA expression were measured after immunoprecipitation and Western blotting and quantitative RT-PCT, respectively. RESULTS: Phagocytosis of HZ/sHZ by human monocytes did not increase iNOS protein and mRNA expression and NO production either after stimulation by IFN-gamma or the cytokine-LPS mix. By contrast, in HZ/sHZ-laden murine macrophages, identical treatment with IFN-gamma and the cytokine-LPS mix elicited significant increases in protein and mRNA expression of iNOS and NOS metabolites production, in agreement with literature data. CONCLUSION: Results indicate that human monocytes fed or not with HZ/sHZ were constantly unable to express iNOS and generate NOS metabolites even after stimulation with IFN-gamma or a cytokine-LSP mix that were very active on HZ-fed murine phagocytic lines. Present data do not support the hypothesis that monocytes are mediators of anti-parasitic defence in clinical malaria via activation of iNOS and production of NO, and suggest caution in extrapolating data obtained with murine or hybrid systems to human malaria.


Assuntos
Citocinas/imunologia , Hemeproteínas/imunologia , Lipopolissacarídeos/imunologia , Malária/imunologia , Monócitos/imunologia , Óxido Nítrico Sintase Tipo II/biossíntese , Óxido Nítrico/biossíntese , Proteínas de Fase Aguda/imunologia , Animais , Western Blotting , Proteínas de Transporte/imunologia , Linhagem Celular , Células Cultivadas , Regulação da Expressão Gênica , Humanos , Glicoproteínas de Membrana/imunologia , Camundongos , Óxido Nítrico Sintase Tipo II/genética , Fagócitos/imunologia , Plasmodium falciparum/imunologia , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
Data Brief ; 7: 514-7, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27054151

RESUMO

This data article is related to the research article entitled "The RING for gypsy moth control: topical application of fragment of its nuclear polyhedrosis virus anti-apoptosis gene as insecticide" [1]. This article reports on significantly higher survival of gypsy moth Lymantria dispar male individuals in response to topical application of single-stranded DNA, based on RING (really interesting new gene) domain fragment of LdMNPV (L. dispar multicapsid nuclear polyhedrosis virus) IAP-3 (inhibitor of apoptosis) gene and acted as DNA insecticide.

18.
Oxid Med Cell Longev ; 2015: 638416, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25969702

RESUMO

Oxidative stress plays an important role in the pathogenesis of falciparum malaria, a disease still claiming close to 1 million deaths and 200 million new cases per year. Most frequent complications are severe anemia, cerebral malaria, and immunodepression, the latter being constantly present in all forms of malaria. Complications are associated with oxidative stress and lipoperoxidation. Its final product 4-hydroxynonenal (4-HNE), a stable yet very reactive and diffusible molecule, forms covalent conjugates with proteins, DNA, and phospholipids and modulates important cell functions at very low concentrations. Since oxidative stress plays important roles in the pathogenesis of severe malaria, it appears important to explore the role of 4-HNE in two important malaria complications such as malaria anemia and malaria immunodepression where oxidative stress is considered to be involved. In this review we will summarize data about 4-HNE chemistry, its biologically relevant chemical properties, and its role as regulator of physiologic processes and as pathogenic factor. We will review studies documenting the role of 4-HNE in severe malaria with emphasis on malaria anemia and immunodepression. Data from other diseases qualify 4-HNE both as oxidative stress marker and as pathomechanistically important molecule. Further studies are needed to establish 4-HNE as accepted pathogenic factor in severe malaria.


Assuntos
Aldeídos/metabolismo , Anemia/complicações , Malária/patologia , Aldeídos/química , Anemia/metabolismo , Células Dendríticas/citologia , Células Dendríticas/imunologia , Eritrócitos/metabolismo , Humanos , Peroxidação de Lipídeos , Malária/imunologia , Malária/metabolismo
19.
Data Brief ; 5: 893-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26702418

RESUMO

The data show the frequencies by which the amino acid residues lysine, histidine and cysteine of six proteins of the malaria parasite Plasmodium falciparum are post-translationally modified by the lipoperoxydation endproduct 4-hydroxynonenal after challenging the parasitized red blood cell with plakortin. Plakortin is an antimalarial endoperoxide whose molecular anti-parasitic effect is described in Skorokhod et al. (2015) [1]. Plakortin did not elicit hemoglobin leakage from host red blood cells and did not oxidize reduced glutathione.

20.
Free Radic Biol Med ; 89: 624-37, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26459031

RESUMO

Plakortin, a polyketide endoperoxide from the sponge Plakortis simplex has antiparasitic activity against P. falciparum. Similar to artemisinin, its activity depends on the peroxide functionality. Plakortin induced stage-, dose- and time-dependent morphologic anomalies, early maturation delay, ROS generation and lipid peroxidation in the parasite. Ring damage by 1 and 10 µM plakortin led to parasite death before schizogony at 20 and 95%, respectively. Treatment of late schizonts with 1, 2, 5 and 10 µM plakortin resulted in decreased reinfection rates by 30, 50, 61 and 65%, respectively. In both rings and trophozoites, plakortin induced a dose- and time-dependent ROS production as well as a significant lipid peroxidation and up to 4-fold increase of the lipoperoxide breakdown product 4-hydroxynonenal (4-HNE). Antioxidants and the free radical scavengers trolox and N-acetylcysteine significantly attenuated the parasite damage. Plakortin generated 4-HNE conjugates with the P. falciparum proteins: heat shock protein Hsp70-1, endoplasmatic reticulum-standing Hsp70-2 (BiP analogue), V-type proton ATPase catalytic subunit A, enolase, the putative vacuolar protein sorting-associated protein 11, and the dynein heavy chain-like protein, whose specific binding sites were identified by mass spectrometry. These proteins are crucially involved in protein trafficking, transmembrane and vesicular transport and parasite survival. We hypothesize that binding of 4-HNE to functionally relevant parasite proteins may explain the observed plakortin-induced morphologic aberrations and parasite death. The identification of 4-HNE-protein conjugates may generate a novel paradigm to explain the mechanism of action of pro-oxidant, peroxide-based antimalarials such as plakortin, artemisinins and synthetic endoperoxides.


Assuntos
Antimaláricos/farmacologia , Malária , Peróxidos/farmacologia , Plakortis , Policetídeos/farmacologia , Animais , Western Blotting , Eritrócitos/parasitologia , Citometria de Fluxo , Humanos , Microscopia de Fluorescência , Estresse Oxidativo/efeitos dos fármacos , Plasmodium falciparum , Espécies Reativas de Oxigênio/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
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