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1.
Immunol Invest ; : 1-14, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38634569

RESUMO

BACKGROUND: The process of tissue injury in coronary artery disease (CAD) has been associated with activation of the complement system, partly due to the action of mannose-binding lectin (MBL) and C3, which are expressed in atherosclerotic lesions. OBJECTIVE: The aim of this study was to evaluate the serum levels of MBL and C3 in patients with CAD and to compare them with healthy controls. Additionally, we aim to assess the correlation between MBL and C3 levels and cardiometabolic parameters. METHODS: MBL and C3 serum concentration were determined by ELISA and immunoturbidimetry, respectively, in up to 119 patients undergoing coronary angiography for CAD evaluation, comprising 48 individuals diagnosed with acute myocardial infarction (MI) and 71 without MI. A total of 93 paired healthy controls were included in the study. RESULTS: Individuals with CAD had MBL serum concentration higher than controls (p = .002), regardless of the presence of MI (p = .006). In addition, high concentration of MBL (>2000 ng/mL) was more frequent in patients with CAD (p = .007; OR = 2.6; 95% CI = 1.3-5.1). C3 levels were not significantly associated with any of the patient groups but were positively correlated with cardiometabolic parameters such as body mass index (BMI) and triglycerides levels. CONCLUSIONS: Higher concentrations of MBL were found to be associated with CAD, whereas C3 levels were found to be associated with cardiovascular risk factors.

2.
Parasite Immunol ; 43(6): e12829, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33686686

RESUMO

AIMS: To investigate whether FCN3 polymorphisms and circulating ficolin-3 levels were associated with clinical forms of chronic Chagas disease (CD) and to assess their potential use as biomarkers for the disease or its severity. METHODS AND RESULTS: FCN3 polymorphisms (g.1637delC (rs532781899) in exon 5; g.3524_3532insTATTTGGCC (rs28362807) in intron 5 and g.4473C > A) (rs4494157) in intron 7) were determined in 178 chronic CD patients (65 asymptomatic, 68 cardiac, 21 digestive and 24 cardiodigestive), and 285 healthy controls by sequence-specific PCR. Ficolin-3 serum levels, measured by ELISA in 80 patients and 80 controls, did not differ between groups. On the other hand, ficolin-3 levels were positively correlated with left ventricular ejection fraction (P = .002; r = .5), with lower levels associated with increased risk of cardiac insufficiency (P = .033; OR 7.21, 95%IC 1.17-44.4). Ficolin-3 levels were positively correlated with ficolin-2 (P = .021; r = .63), and negatively with MBL (P = .002; r = -.36) and pentraxin-3 (P = .04; r = -.32) levels. No significant results were observed for the investigated FCN3 polymorphisms and CD. The g.1637del/1637C heterozygotes presented lower ficolin-3 levels than g.1637C/1637C homozygotes in the control group (P = .023). CONCLUSION: Low ficolin-3 levels may play a role in the pathophysiology of cardiac insufficiency associated with CD.


Assuntos
Doença de Chagas , Cardiopatias , Lectinas , Doença de Chagas/genética , Humanos , Lectinas/genética , Volume Sistólico , Função Ventricular Esquerda
3.
PLoS Negl Trop Dis ; 14(4): e0007534, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32240160

RESUMO

BACKGROUND: Deposition of complement factors on Mycobacterium leprae may enhance phagocytosis. Such deposition may occur through the lectin pathway of complement. Three proteins of the lectin pathway are produced from the gene MASP1: Mannan-binding lectin-associated serine protease 1 (MASP-1) and MASP-3 and mannan-binding lectin-associated protein of 44 kDa (MAp44). Despite their obvious importance, the roles played by these proteins have never been investigated in leprosy disease. METHODOLOGY: We haplotyped five MASP1 polymorphisms by multiplex sequence-specific PCR (intronic rs7609662*G>A and rs13064994*C>T, exon 12 3'-untranslated rs72549262*C>G, rs1109452*C>T and rs850314*G>A) and measured MASP-1, MASP-3 and MAp44 serum levels in 196 leprosy patients (60%, lepromatous) and 193 controls. PRINCIPAL FINDINGS: Lower MASP-3 and MAp44 levels were observed in patients, compared with controls (P = 0.0002 and P<0.0001, respectively) and in lepromatous, compared with non-lepromatous patients (P = 0.008 and P = 0.002, respectively). Higher MASP-3 levels were present in controls carrying variants/haplotypes associated with leprosy resistance (rs13064994*T, rs1109452_rs850314*CG within GT_CCG and rs850314*A: OR = 0.5-0.6, Pcorr = 0.01-0.04). Controls with rs1109452*T, included in susceptibility haplotypes (GT_GTG/GT_CTG: OR = 2.0, Pcorr = 0.03), had higher MASP-1 and lower MASP-3 levels (P≤0.009). Those with GC_CCG, presented increasing susceptibility (OR = 1.7, Pcorr = 0.006) and higher MAp44 levels (P = 0.015). MASP-3 expression decreased in patients, compared with controls carrying rs1109452_rs850314*CA or CG (P≤0.02), which may rely on exon 12 CpG methylation and/or miR-2861/miR-3181 mRNA binding. CONCLUSION: Polymorphisms regulating MASP-3/MAp44 availability in serum modulate leprosy susceptibility, underlining the importance of lectin pathway regulation against pathogens that exploit phagocytosis to parasitize host macrophages.


Assuntos
Predisposição Genética para Doença , Hanseníase/genética , Hanseníase/patologia , Serina Proteases Associadas a Proteína de Ligação a Manose/análise , Serina Proteases Associadas a Proteína de Ligação a Manose/genética , Mycobacterium leprae/imunologia , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Estudos Transversais , Feminino , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
4.
Front Public Health ; 7: 166, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31312626

RESUMO

Carlos Chagas discovered American trypanosomiasis, also named Chagas disease (CD) in his honor, just over a century ago. He described the clinical aspects of the disease, characterized by its etiological agent (Trypanosoma cruzi) and identified its insect vector. Initially, CD occurred only in Latin America and was considered a silent and poorly visible disease. More recently, CD became a neglected worldwide disease with a high morbimortality rate and substantial social impact, emerging as a significant public health threat. In this context, it is crucial to better understand better the epidemiological scenarios of CD and its transmission dynamics, involving people infected and at risk of infection, diversity of the parasite, vector species, and T. cruzi reservoirs. Although efforts have been made by endemic and non-endemic countries to control, treat, and interrupt disease transmission, the cure or complete eradication of CD are still topics of great concern and require global attention. Considering the current scenario of CD, also affecting non-endemic places such as Canada, USA, Europe, Australia, and Japan, in this review we aim to describe the spread of CD cases worldwide since its discovery until it has become a global public health concern.

5.
PLoS Negl Trop Dis ; 13(4): e0007324, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30995222

RESUMO

Chagas Disease (CD) is an anthropozoonosis caused by Trypanosoma cruzi. With complex pathophysiology and variable clinical presentation, CD outcome can be influenced by parasite persistence and the host immune response. Complement activation is one of the primary defense mechanisms against pathogens, which can be initiated via pathogen recognition by pattern recognition molecules (PRMs). Collectin-11 is a multifunctional soluble PRM lectin, widely distributed throughout the body, with important participation in host defense, homeostasis, and embryogenesis. In complex with mannose-binding lectin-associated serine proteases (MASPs), collectin-11 may initiate the activation of complement, playing a role against pathogens, including T. cruzi. In this study, collectin-11 plasma levels and COLEC11 variants in exon 7 were assessed in a Brazilian cohort of 251 patients with chronic CD and 108 healthy controls. Gene-gene interactions between COLEC11 and MASP2 variants were analyzed. Collectin-11 levels were significantly decreased in CD patients compared to controls (p<0.0001). The allele rs7567833G, the genotypes rs7567833AG and rs7567833GG, and the COLEC11*GGC haplotype were related to T. cruzi infection and clinical progression towards symptomatic CD. COLEC11 and MASP2*CD risk genotypes were associated with cardiomyopathy (p = 0.014; OR 9.3, 95% CI 1.2-74) and with the cardiodigestive form of CD (p = 0.005; OR 15.2, 95% CI 1.7-137), suggesting that both loci act synergistically in immune modulation of the disease. The decreased levels of collectin-11 in CD patients may be associated with the disease process. The COLEC11 variant rs7567833G and also the COLEC11 and MASP2*CD risk genotype interaction were associated with the pathophysiology of CD.


Assuntos
Doença de Chagas/genética , Doença de Chagas/fisiopatologia , Colectinas/genética , Epistasia Genética , Serina Proteases Associadas a Proteína de Ligação a Manose/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Estudos de Casos e Controles , Colectinas/sangue , Feminino , Predisposição Genética para Doença , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
6.
Am J Trop Med Hyg ; 100(1): 93-96, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30526728

RESUMO

Chagas disease (CD), caused by infection with the parasite Trypanosoma cruzi, leads to severe cardiomyopathy in 20-30% of patients, whereas the remainder may stay asymptomatic and never develop cardiomyopathy or other clinical manifestations. The underlying cause for this variable outcome is not fully characterized, although previous studies have found high levels of circulating mannose-binding lectin (MBL) to be associated with cardiac failure echocardiographic changes. We report three indeterminate (asymptomatic) chronic Chagas patients who were followed up for 10 years. Two of these patients developed chronic chagasic cardiomyopathy (CCC) during this follow-up period and, when genotyped, were found to be carriers of the high MBL producer HYPA/HYPA genotype, suggesting that genetically determined high MBL serum might be associated with the risk of CCC development. These results suggest the use of MBL quantification and MBL2 genotyping as tools for clinical assessment in patients with chronic CD.


Assuntos
Cardiomiopatia Chagásica/diagnóstico , Progressão da Doença , Lectina de Ligação a Manose/sangue , Lectina de Ligação a Manose/genética , Idoso , Infecções Assintomáticas , Brasil , Cardiomiopatia Chagásica/etiologia , Doença Crônica , Ensaio de Imunoadsorção Enzimática , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Trypanosoma cruzi
7.
Mater Sci Eng C Mater Biol Appl ; 93: 70-79, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30274103

RESUMO

Capsaicin (CAP) is a secondary metabolite with high therapeutic potential. It displays several bioactive properties including hypolipidemic, antioxidant, anti-inflammatory and analgesic effects. However, CAP presents toxicity to healthy cells and poor pharmacokinetic profile, which is characterized by toxic metabolites and short half-life. In this study, CAP-loaded albumin nanoparticles were obtained by the desolvation-coacervation method. The preparation process was optimized by the application of a factorial design. Nanoparticles presented diameter of about 200 nm, quasi-spherical morphology, encapsulation efficiency of 98.3 ±â€¯7.4%, and negative zeta potential. The in vitro release assay demonstrated a biphasic profile, characterized by a fast release over 12 h followed by a prolonged release rate. Nanoencapsulated CAP showed significant antioxidant activity in an in vitro assay which was concentration - and time-dependent. In addition, the in vivo study demonstrated for the first time that both free and nanoencapsulated drug reduced TNF-alpha concentrations in the absence of inflammatory stimuli model. These novel findings indicate that albumin nanoparticles are potential CAP carriers and that this new drug formulation may be useful in several conditions, including cancer, inflammation, and neuropathic pain.


Assuntos
Capsaicina , Nanocápsulas , Soroalbumina Bovina , Animais , Capsaicina/química , Capsaicina/farmacocinética , Capsaicina/farmacologia , Bovinos , Masculino , Nanocápsulas/química , Nanocápsulas/uso terapêutico , Ratos , Ratos Wistar , Soroalbumina Bovina/química , Soroalbumina Bovina/farmacocinética , Soroalbumina Bovina/farmacologia
8.
Front Immunol ; 9: 2292, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30349535

RESUMO

The complement system is a key component of the innate immune system, participating in the surveillance against infectious agents. Once activated by one of the three different pathways, complement mediates cell lysis, opsonization, signalizes pathogens for phagocytosis and induces the adaptive immune response. The lectin pathway is constituted by several soluble and membrane bound proteins, called pattern recognition molecules (PRM), including mannose binding lectin (MBL), Ficolins-1, -2, and -3, and Collectin 11. These PRMs act on complement activation as recognition molecules of pathogen-associated molecular patterns (PAMPs) such as N-acetylated, found in glycoproteins of viral envelopes. In this study, Ficolin-1 and Ficolin-3 plasma levels were evaluated in 178 HIV patients (93 HIV; 85 HIV/HCV) and 85 controls from southern Brazil. Demographic and clinical-laboratory findings were obtained during medical interview and from medical records. All parameters were assessed by logistic regression, adjusted for age, ancestry, and sex. Significantly lower levels of Ficolin-1 were observed in HIV/HCV coinfected when compared to HIV patients (p = 0.005, median = 516 vs. 667 ng/ul, respectively) and to controls (p < 0.0001, 1186 ng/ul). Ficolin-1 levels were lower in males than in females among HIV patients (p = 0.03) and controls (p = 0.0003), but no association of Ficolin-1 levels with AIDS was observed. On the other hand, Ficolin-3 levels were significantly lower in controls when compared to HIV (p < 0.0001, medians 18,240 vs. 44,030 ng/ml, respectively) and HIV/HCV coinfected (p < 0.0001, 40,351 ng/ml) patients. There was no correlation between Ficolin-1 and Ficolin-3 levels and age, HIV viral load or opportunistic infections. However, Ficolin-3 showed a positive correlation with T CD4 cell counts in HIV monoinfected patients (p = 0.007). We provide here the first assessment of Ficolin-1 and-3 levels in HIV and HIV/HCV coinfected patients, which indicates a distinct role for these pattern recognition molecules in both viral infections.


Assuntos
Glicoproteínas/sangue , Infecções por HIV/sangue , Hepatite C/sangue , Lectinas/sangue , Adulto , Idoso , Brasil , Coinfecção/sangue , Feminino , Infecções por HIV/complicações , Hepatite C/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Ficolinas
9.
Phytomedicine ; 47: 105-112, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30166094

RESUMO

BACKGROUND: Medicinal plants are an important source to identify new active pharmaceutical compounds. Traditionally, the sap of Euphorbia umbellata is widely used to treat cancer and inflammatory conditions. These effects have been attributed to the presence of terpenes and phenolic compounds in the extracts of this plant. Euphol, a tetracyclic triterpene alcohol, is one of the major compounds present in Euphorbia species, and some biological activities have been attributed to this compound. PURPOSE: This study aimed to evaluate the in vitro cytotoxicity of euphol against Jurkat, HL-60, K-562, B16F10, and HRT-18 cells lines, as well as the biological stability, distribution, metabolism properties in vitro, and the determination of the concentration of euphol in the plasma and liver of rats. METHODS: The MTT reduction assay was used to evaluate the cytotoxicity of euphol against cancer cell lines, and the selectivity index, the morphology and cell cycle assays to evaluate the death mechanisms in K-562 and B16F10 lineages. UHPLC-MS was applied for the in vivo evaluation of the concentration of euphol in plasma and liver, and in vitro metabolic stability in human liver microsomes and S9 fraction, plasma protein binding, and stability in simulated gastric and intestinal fluids assays. CONCLUSIONS: This study demonstrated that euphol exhibited cytotoxic effects against a variety of cancer cells lines, selectivity against leukemia and possibly, the mechanism involved is apoptosis. The evaluation of stability, distribution, and metabolism properties showed that euphol was unstable in gastric and intestinal fluids, presenting moderate plasma protein binding with two hours elimination half-life and possible phase II liver metabolism. All the results suggested that further studies could be developed to prove the viability of euphol as an anticancer agent.


Assuntos
Euphorbia/química , Lanosterol/análogos & derivados , Látex/química , Animais , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Células Jurkat , Lanosterol/farmacologia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Ratos
10.
Front Immunol ; 9: 1842, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30127792

RESUMO

Chagas disease (CD), a neglected tropical disease caused by the protozoan Trypanosoma cruzi, affects around six million individuals in Latin America. Currently, CD occurs worldwide, becoming a significant public health concern due to its silent aspect and high morbimortality rate. T. cruzi presents different escape strategies which allow its evasion from the host immune system, enabling its persistence and the establishment of chronic infection which leads to the development of chronic Chagas cardiomyopathy (CCC). The potent immune stimuli generated by T. cruzi persistence may result in tissue damage and inflammatory response. In addition, molecular mimicry between parasites molecules and host proteins may result in cross-reaction with self-molecules and consequently in autoimmune features including autoantibodies and autoreactive cells. Although controversial, there is evidence demonstrating a role for autoimmunity in the clinical progression of CCC. Nevertheless, the exact mechanism underlying the generation of an autoimmune response in human CD progression is unknown. In this review, we summarize the recent findings and hypotheses related to the autoimmune mechanisms involved in the development and progression of CCC.


Assuntos
Autoimunidade , Doença de Chagas/imunologia , Interações Hospedeiro-Patógeno/imunologia , Animais , Autoanticorpos/imunologia , Cardiomiopatia Chagásica/etiologia , Doença de Chagas/complicações , Doença de Chagas/metabolismo , Doença de Chagas/parasitologia , Proteínas do Sistema Complemento/imunologia , Proteínas do Sistema Complemento/metabolismo , Reações Cruzadas , Humanos , Proteínas de Protozoários/imunologia , Transdução de Sinais , Trypanosoma cruzi/imunologia
11.
Int J Cardiol Heart Vasc ; 20: 27-31, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29992184

RESUMO

BACKGROUND: Mannose binding lectin (MBL) appears to be involved in susceptibility to rheumatoid arthritis (RA), in the inflammatory process and in the genesis of atherosclerotic disease. OBJECTIVE: To study the association of MBL serum levels and its genotypic variation with carotid arteries intimal thickness (IMT) in RA patients from Southern Brazil. METHODS: MBL serum levels, MBL2 genotyping and IMT were investigated in 90 RA patients along with their demographic, clinical and laboratory profile. MBL levels and MBL2 genotyping were evaluated in 90 healthy controls. RESULTS: A significant lower MBL serum concentration was observed in patients with RA in relation to controls (528 ng/mL vs 937.5 ng/mL, p = 0.05, respectively). The median IMT in RA patients was 0.59 mm (0.51 to 0.85 mm). There was no correlation between levels of MBL with disease activity, erythrocyte sedimentation rate, autoantibodies presence or IMT (p = NS). A weak and negative correlation was found between MBL and CRP levels (Rho = -0.24; p = 0.02;). The MBL2 variant at codon 54 (variant B) and HYPA haplotype were the most frequently observed in the RA sample (67.5% and 31.7%). MBL2 wild type (A/A) were associated with lower IMT when compared with heterozygotes (A/O; p = 0.04) and low producers (O/O; p = 0.05). In addition, high producers genotypes had lower levels of CRP when compared with medium (p = 0.04) or with low producers (p = 0.05). CONCLUSION: RA patients had lower MBL levels than controls. MBL were negatively associated with CRP serum levels; low MBL genotypes producers increased thickness of the IMT than high producers.

12.
Int J Immunogenet ; 45(3): 118-127, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29675993

RESUMO

Mannan-binding lectin (MBL) and MBL-associated serine protease 2 (MASP-2) are components of the lectin pathway, which activate the complement system after binding to the HCV structural proteins E1 and E2. We haplotyped 11 MASP2 polymorphisms in 103 HCV patients and 205 controls and measured MASP-2 levels in 67 HCV patients and 77 controls to better understand the role of MASP-2 in hepatitis C susceptibility and disease severity according to viral genotype and fibrosis levels. The haplotype block MASP2*ARDP was associated with protection against HCV infection (OR = 0.49, p = .044) and lower MASP-2 levels in controls (p = .021), while haplotype block AGTDVRC was significantly increased in patients (OR = 7.58, p = .003). MASP-2 levels were lower in patients than in controls (p < .001) and in patients with viral genotype 1 or 4 (poor responders to treatment) than genotype 3 (p = .022) and correlated inversely with the levels of alkaline phosphatase, especially in individuals with fibrosis 3 or 4 (R = -.7, p = .005). MASP2 gene polymorphisms modulate basal gene expression, which may influence the quality of complement response against HCV. MASP-2 levels decrease during chronic disease, independently of MASP2 genotypes, most probably due to consumption and attenuation mechanisms of viral origin and by the reduced liver function, the site of MASP-2 production.


Assuntos
Haplótipos , Hepacivirus , Hepatite C/genética , Hepatite C/metabolismo , Serina Proteases Associadas a Proteína de Ligação a Manose/genética , Serina Proteases Associadas a Proteína de Ligação a Manose/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Estudos de Casos e Controles , Éxons , Feminino , Predisposição Genética para Doença , Genótipo , Hepacivirus/genética , Hepatite C/diagnóstico , Hepatite C/virologia , Humanos , Íntrons , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Índice de Gravidade de Doença , Adulto Jovem
13.
Sci Rep ; 8(1): 526, 2018 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-29323238

RESUMO

Complement is an essential element in both innate and acquired immunity contributing to the immunopathogenesis of many disorders, including Chagas Disease (CD). Human complement receptor 1 (CR1) plays a role in the clearance of complement opsonized molecules and may facilitate the entry of pathogens into host cells. Distinct CR1 exon 29 variants have been found associated with CR1 expression levels, increased susceptibility and pathophysiology of several diseases. In this study, CR1 plasma levels were assessed by ELISA and CR1 variants in exon 29 by sequencing in a Brazilian cohort of 232 chronic CD patients and 104 healthy controls. CR1 levels were significantly decreased in CD patients compared to controls (p < 0.0001). The CR1 rs1704660G, rs17047661G and rs6691117G variants were significantly associated with CD and in high linkage disequilibrium. The CR1*AGAGTG haplotype was associated with T. cruzi infection (p = 0.035, OR 3.99, CI 1.1-14.15) whereas CR1*AGGGTG was related to the risk of chagasic cardiomyopathy (p = 0.028, OR 12.15, CI 1.13-113). This is the first study that provides insights on the role of CR1 in development and clinical presentation of chronic CD.


Assuntos
Doença de Chagas/genética , Polimorfismo de Nucleotídeo Único , Receptores de Complemento 3b/genética , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Haplótipos , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Receptores de Complemento 3b/metabolismo
14.
Front Microbiol ; 8: 607, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28473804

RESUMO

Trypanosoma cruzi is a protozoan parasite known to cause Chagas disease (CD), a neglected sickness that affects around 6-8 million people worldwide. Originally, CD was mainly found in Latin America but more recently, it has been spread to countries in North America, Asia, and Europe due the international migration from endemic areas. Thus, at present CD represents an important concern of global public health. Most of individuals that are infected by T. cruzi may remain in asymptomatic form all lifelong, but up to 40% of them will develop cardiomyopathy, digestive mega syndromes, or both. The interaction between the T. cruzi infective forms and host-related immune factors represents a key point for a better understanding of the physiopathology of CD. In this context, the complement, as one of the first line of host defense against infection was shown to play an important role in recognizing T. cruzi metacyclic trypomastigotes and in controlling parasite invasion. The complement consists of at least 35 or more plasma proteins and cell surface receptors/regulators, which can be activated by three pathways: classical (CP), lectin (LP), and alternative (AP). The CP and LP are mainly initiated by immune complexes or pathogen-associated molecular patterns (PAMPs), respectively, whereas AP is spontaneously activated by hydrolysis of C3. Once activated, several relevant complement functions are generated which include opsonization and phagocytosis of particles or microorganisms and cell lysis. An important step during T. cruzi infection is when intracellular trypomastigotes are release to bloodstream where they may be target by complement. Nevertheless, the parasite uses a sequence of events in order to escape from complement-mediated lysis. In fact, several T. cruzi molecules are known to interfere in the initiation of all three pathways and in the assembly of C3 convertase, a key step in the activation of complement. Moreover, T. cruzi promotes secretion of plasma membrane-derived vesicles from host cells, which prevent the activity of C3 convertase C4b2a and thereby may hinder complement. In this review, we aim to present an overview on the strategies used by T. cruzi in order to circumvent the activation of complement and, consequently, its biological effects.

15.
Int J Cardiol ; 221: 298-301, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-27404695

RESUMO

BACKGROUND: Pentraxin-3 (PTX3) is a long pentraxin that is supposed to participate in the inflammatory process and in atherosclerosis. AIM: To study PTX3 serum levels in rheumatoid arthritis (RA) patients to know if its serum levels may reflect disease activity and/or subclinical atherosclerosis. METHODS: PTX3 and carotid intima media thickness (IMT) were studied in 85 RA patients (83.5% females, median age of 59years old, median disease duration of 13years) along with its demographic, clinical, serological and lipid profile. For comparison PTX3 was measured in 85 healthy volunteers. RESULTS: PTX3 levels in RA patients were similar to controls (p=0.21) and did not correlate with inflammatory activity measured by ESR (p=0.39) CRP (p=0.18) and DAS28 (p=0.67). Serum PTX3 levels were higher in nonobese RA patients than in obese (BMI vs PTX3 with rho=-0.27; 95%IC=-0.46 to -0.06; p=0.009). In non-obese patients, PTX3 correlated negatively with carotid IMT (rho=-0.40; 95%IC=-0.66 to -0.06; p=0.01) but not in the obese ones (p=0.26). In the obese RA patients there was a negative correlation between PTX3 levels and LDL/HDL ratio (Rho=-0.29; 95%IC=-0.53-0.01; p=0.03). CONCLUSIONS: PTX3 levels do not reflect inflammatory process in RA. However, it exerts a protective role in the process of atherogenesis in non-obese RA patients.


Assuntos
Artrite Reumatoide/sangue , Artrite Reumatoide/diagnóstico , Proteína C-Reativa/metabolismo , Espessura Intima-Media Carotídea , Obesidade/diagnóstico , Componente Amiloide P Sérico/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Espessura Intima-Media Carotídea/tendências , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/sangue
16.
PLoS Negl Trop Dis ; 10(1): e0004257, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26745156

RESUMO

Chagas disease (CD) is caused by Trypanosoma cruzi, whose sugar moieties are recognized by mannan binding lectin (MBL), a soluble pattern-recognition molecule that activates the lectin pathway of complement. MBL levels and protein activity are affected by polymorphisms in the MBL2 gene. We sequenced the MBL2 promoter and exon 1 in 196 chronic CD patients and 202 controls. The MBL2*C allele, which causes MBL deficiency, was associated with protection against CD (P = 0.007, OR = 0.32). Compared with controls, genotypes with this allele were completely absent in patients with the cardiac form of the disease (P = 0.003). Furthermore, cardiac patients with genotypes causing MBL deficiency presented less heart damage (P = 0.003, OR = 0.23), compared with cardiac patients having the XA haplotype causing low MBL levels, but fully capable of activating complement (P = 0.005, OR = 7.07). Among the patients, those with alleles causing MBL deficiency presented lower levels of cytokines and chemokines possibly implicated in symptom development (IL9, p = 0.013; PDGFB, p = 0.036 and RANTES, p = 0.031). These findings suggest a protective effect of genetically determined MBL deficiency against the development and progression of chronic CD cardiomyopathy.


Assuntos
Cardiomiopatia Chagásica/genética , Cardiomiopatia Chagásica/prevenção & controle , Resistência à Doença , Lectina de Ligação a Manose/deficiência , Erros Inatos do Metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Lectina de Ligação a Manose/genética , Pessoa de Meia-Idade , Adulto Jovem
17.
Mol Immunol ; 69: 77-85, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26608926

RESUMO

Mannose-binding lectin (MBL) is a pattern recognition receptor of the lectin pathway of complement system. MBL binds to carbohydrates on microorganism's surfaces leading to complement activation, opsonization and phagocytosis. Polymorphisms in the MBL gene (MBL2) are associated with variations on MBL serum levels and with the susceptibility to various infectious and autoimmune diseases. The involvement of the lectin pathway in rheumatoid arthritis (RA) has been demonstrated by several studies and although MBL has been considered to have a dual role in the pathogenesis of the disease, the association between MBL and RA remains inconclusive. In an attempt to clarify this relationship, we developed this short review summarizing accumulated evidences in regard to MBL and RA and a meta-analysis to evaluate the influence of MBL2 polymorphisms on the susceptibility to RA. Among a total of 217 articles that were identified following a predefined search strategy on PubMed, Scopus, Scielo, EMBASE and Cochrane databases, only 13 met all inclusion criteria and were included in the meta-analysis. Data assessment was conducted by three independent investigators and presented in odds ratio (OR) and 95% confidence intervals (CIs) using forest plot charts. Both heterogeneity and publication bias were analyzed. The results of the meta-analysis evidenced that MBL2 low producing OO and XX genotypes do not confer higher risk to RA, even when data were analyzed according to cohort's ethnicity. Further studies are needed in order to clarify the importance of other genes of the lectin pathway in the pathogenesis of RA.


Assuntos
Artrite Reumatoide/genética , Predisposição Genética para Doença/genética , Lectina de Ligação a Manose/genética , Polimorfismo Genético , Animais , Genótipo , Humanos
18.
Rev. bras. farmacogn ; 25(2): 85-91, Mar-Apr/2015. graf
Artigo em Inglês | LILACS | ID: lil-749861

RESUMO

Abstract Piper amalago L., Piperaceae, popularly known as jaborandi-manso, is a shrub that spans a height of 2–7 m. It can be found in the regions of Southern America downward up to the south of Brazil. Traditionally it is used to treat digestive problems, heart problems, and burns. This study aims to conduct an anatomical investigation and analysis of the leaves and stems of P. amalago through electron scanning and optical micro techniques. The analysis showed that P. amalago has a hypostomatic leaf, with a subepidermal layer on its surface. There are grandular trichomes that resemble sacs, conic non-glandular trichomes, dorsiventral mesophyll, and a plano-convex midrib having a single vascular bundle in the center. The petiole is short with irregularly shaped and adaxially grooved. The stem is circular in shape and contains two circles of vascular bundles and a sclerenchymatic sheath in the perimedular region. These anatomical features of the Piper amalago's leaves and stems make it easy to pick it out among other species of the Piper genus. This is helpful when conducting quality control process.

19.
Mem Inst Oswaldo Cruz ; 109(4): 442-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25004147

RESUMO

The aim of the present study was to detect natural infection by Leishmania (Leishmania) infantum in Lutzomyia longipalpis captured in Barcarena, state of Pará, Brazil, through the use of three primer sets. With this approach, it is unnecessary to previously dissect the sandfly specimens. DNA of 280 Lu. longipalpis female specimens were extracted from the whole insects. PCR primers for kinetoplast minicircle DNA (kDNA), the mini-exon gene and the small subunit ribosomal RNA (SSU-rRNA) gene of Leishmania were used, generating fragments of 400 bp, 780 bp and 603 bp, respectively. Infection by the parasite was found with the kDNA primer in 8.6% of the cases, with the mini-exon gene primer in 7.1% of the cases and with the SSU-rRNA gene primer in 5.3% of the cases. These data show the importance of polymerase chain reaction as a tool for investigating the molecular epidemiology of visceral leishmaniasis by estimating the risk of disease transmission in endemic areas, with the kDNA primer representing the most reliable marker for the parasite.


Assuntos
Primers do DNA/genética , DNA de Cinetoplasto/genética , DNA de Protozoário/genética , Insetos Vetores/parasitologia , Leishmania infantum/genética , Psychodidae/parasitologia , Animais , Feminino , Marcadores Genéticos , Insetos Vetores/classificação , Leishmania infantum/isolamento & purificação , Reação em Cadeia da Polimerase , Psychodidae/classificação , Sensibilidade e Especificidade
20.
Mem. Inst. Oswaldo Cruz ; 109(4): 442-447, 03/07/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-716300

RESUMO

The aim of the present study was to detect natural infection by Leishmania (Leishmania) infantum in Lutzomyia longipalpis captured in Barcarena, state of Pará, Brazil, through the use of three primer sets. With this approach, it is unnecessary to previously dissect the sandfly specimens. DNA of 280 Lu. longipalpis female specimens were extracted from the whole insects. PCR primers for kinetoplast minicircle DNA (kDNA), the mini-exon gene and the small subunit ribosomal RNA (SSU-rRNA) gene of Leishmania were used, generating fragments of 400 bp, 780 bp and 603 bp, respectively. Infection by the parasite was found with the kDNA primer in 8.6% of the cases, with the mini-exon gene primer in 7.1% of the cases and with the SSU-rRNA gene primer in 5.3% of the cases. These data show the importance of polymerase chain reaction as a tool for investigating the molecular epidemiology of visceral leishmaniasis by estimating the risk of disease transmission in endemic areas, with the kDNA primer representing the most reliable marker for the parasite.


Assuntos
Animais , Feminino , Primers do DNA/genética , DNA de Cinetoplasto/genética , DNA de Protozoário/genética , Insetos Vetores/parasitologia , Leishmania infantum/genética , Psychodidae/parasitologia , Marcadores Genéticos , Insetos Vetores/classificação , Leishmania infantum/isolamento & purificação , Reação em Cadeia da Polimerase , Psychodidae/classificação , Sensibilidade e Especificidade
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