Down-regulation of autophagy proteins is associated with higher mTOR expression in the placenta of pregnant women with preeclampsia.

Autophagy is a lysosomal degradation pathway that removes protein aggregates and damaged organelles maintaining cellular integrity. It seems to be essential for cell survival during stress, starvation, hypoxia, and consequently to the placenta implantation and development. Preeclampsia (PE) is a multisystemic disorder characterized by the onset of hypertension associated or not with proteinuria and other maternal complications. Considering that the placenta seems to play an important role in the pathogenesis of PE, the objective of the present study was to evaluate protein levels of light chain protein (LC3), beclin-1, and the mammalian target of rapamycin (mTOR) in the placenta of pregnant women with PE. Placental tissues collected from 20 women with PE and 20 normotensive (NT) pregnant women were evaluated for LC3, beclin-1, and mTOR expression by qPCR and immunohistochemistry. The mRNA for LC3 and beclin-1 were significantly lower, while mTOR gene expression was significantly higher in the placenta of pregnant women with PE than in the NT group. Placentas of PE women showed significantly decreased protein expression of LC3-II and beclin-1, whereas mTOR was significantly increased compared with the NT pregnant women. There was a negative correlation between protein expression of mTOR and LC3-II in the placental tissue of PE women. In conclusion, the results showed autophagy deficiency suggesting that failure in this degradation process may contribute to the pathogenesis of PE; however, new studies involving cross-talk between autophagy and inflammatory molecular mechanisms might help to better understand the autophagy process in this obstetric pathology.

Down-regulation of autophagy proteins is associated with higher mTOR expression in the placenta of pregnant women with preeclampsia

Autophagy is a lysosomal degradation pathway that removes protein aggregates and damaged organelles maintaining cellular integrity. It seems to be essential for cell survival during stress, starvation, hypoxia, and consequently to the placenta implantation and development. Preeclampsia (PE) is a multisystemic disorder characterized by the onset of hypertension associated or not with proteinuria and other maternal complications. Considering that the placenta seems to play an important role in the pathogenesis of PE, the objective of the present study was to evaluate protein levels of light chain protein (LC3), beclin-1, and the mammalian target of rapamycin (mTOR) in the placenta of pregnant women with PE. Placental tissues collected from 20 women with PE and 20 normotensive (NT) pregnant women were evaluated for LC3, beclin-1, and mTOR expression by qPCR and immunohistochemistry. The mRNA for LC3 and beclin-1 were significantly lower, while mTOR gene expression was significantly higher in the placenta of pregnant women with PE than in the NT group. Placentas of PE women showed significantly decreased protein expression of LC3-II and beclin-1, whereas mTOR was significantly increased compared with the NT pregnant women. There was a negative correlation between protein expression of mTOR and LC3-II in the placental tissue of PE women. In conclusion, the results showed autophagy deficiency suggesting that failure in this degradation process may contribute to the pathogenesis of PE; however, new studies involving cross-talk between autophagy and inflammatory molecular mechanisms might help to better understand the autophagy process in this obstetric pathology.

Effects of vitamin D-induced supernatant of placental explants from preeclamptic women on oxidative stress and nitric oxide bioavailability in human umbilical vein endothelial cells.

The study evaluated the effect of the supernatant of placental explants from preeclamptic (PE) and normotensive (NT) pregnant women after tissue treatment with or without vitamin D (VD) on oxidative stress and nitric oxide (NO) bioavailability in human umbilical vein endothelial cells (HUVEC). Placental explants were prepared from eight NT and eight PE women, and supernatants were obtained after incubation with or without hydrogen peroxide (H2O2) and/or VD. HUVEC were cultured for 24 h with supernatants, and the following parameters were analyzed in HUVEC cultures: NO, nitrate (NO3-), and nitrite (NO2-) levels, lipid peroxidation, and intracellular reactive oxygen species (ROS). Results showed that the production of NO3-, NO2-, malondialdehyde (MDA), and ROS were significantly higher in HUVEC treated with explant supernatant from PE compared to NT pregnant women, while the supernatant of PE explants treated with VD led to a decrease in these parameters. A significantly high production of NO was detected in HUVEC cultured with control supernatant of NT group, and in cultures treated with supernatant of PE explants treated with VD. Taken together, these results demonstrated that cultures of placental explants from PE women with VD treatment generated a supernatant that decreased oxidative stress and increased the bioavailability of NO in endothelial cells.

Effects of vitamin D-induced supernatant of placental explants from preeclamptic women on oxidative stress and nitric oxide bioavailability in human umbilical vein endothelial cells

The study evaluated the effect of the supernatant of placental explants from preeclamptic (PE) and normotensive (NT) pregnant women after tissue treatment with or without vitamin D (VD) on oxidative stress and nitric oxide (NO) bioavailability in human umbilical vein endothelial cells (HUVEC). Placental explants were prepared from eight NT and eight PE women, and supernatants were obtained after incubation with or without hydrogen peroxide (H2O2) and/or VD. HUVEC were cultured for 24 h with supernatants, and the following parameters were analyzed in HUVEC cultures: NO, nitrate (NO3-), and nitrite (NO2-) levels, lipid peroxidation, and intracellular reactive oxygen species (ROS). Results showed that the production of NO3-, NO2-, malondialdehyde (MDA), and ROS were significantly higher in HUVEC treated with explant supernatant from PE compared to NT pregnant women, while the supernatant of PE explants treated with VD led to a decrease in these parameters. A significantly high production of NO was detected in HUVEC cultured with control supernatant of NT group, and in cultures treated with supernatant of PE explants treated with VD. Taken together, these results demonstrated that cultures of placental explants from PE women with VD treatment generated a supernatant that decreased oxidative stress and increased the bioavailability of NO in endothelial cells.

Maternal left ventricular hypertrophy and diastolic dysfunction and brain natriuretic peptide concentration in early- and late-onset pre-eclampsia.

OBJECTIVE: Pre-eclampsia (PE) is associated with maternal cardiac remodeling and diastolic dysfunction. The aim of this study was to assess and compare maternal left ventricular structure and diastolic function and levels of brain natriuretic peptide (BNP) in women with early-onset (< 34 weeks' gestation) vs those with late-onset (≥ 34 weeks' gestation) PE. METHODS: This was a prospective, cross-sectional, observational study of 30 women with early-onset PE, 32 with late-onset PE and 23 normotensive controls. Maternal cardiac structure and diastolic function were assessed by echocardiography and plasma levels of BNP were measured by enzyme immunoassay. RESULTS: Early- and late-onset PE were associated with increased left ventricular mass index and relative wall thickness compared with normotensive controls. In women with early-onset PE, the prevalence of concentric hypertrophy (40%) and diastolic dysfunction (23%) was also significantly higher (both P < 0.05) compared with women with late-onset PE (16% for both). Maternal serum BNP levels were significantly higher (P < 0.05) in women with early-onset PE and correlated with relative wall thickness and left ventricular mass index. CONCLUSIONS: Early-onset PE is associated with more severe cardiac impairment than is late-onset PE, as evidenced by an increased prevalence of concentric hypertrophy, diastolic dysfunction and higher levels of BNP. These findings suggest that early-onset PE causes greater myocardial damage, increasing the risk of both peripartum and postpartum cardiovascular morbidity. Although these cardiovascular effects are easily identified by echocardiographic parameters and measuring BNP, further studies are needed to assess their clinical utility. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Quantificação de citocinas no soro e homogenato da pata na intoxicação experimental com veneno de Bothropoides jararaca em ratos Wistar tratados com soroterapia e Mikania glomerata / Quantification of cytokines in serum and paw homogenate of experimental intoxication for venom of the Bothropoides jararaca in Wistar rats treated with antivenom and Mikania glomerata

O presente estudo teve como objetivo quantificar os níveis de citocinas pró-inflamatórias, entre as quais TNF-α, interleucina-1β (IL-1β), IL-6, e anti-inflamatórias, como IL-10, interferon-γ (INF-γ), bem como comparar o efeito do tratamento convencional com o efeito do tratamento complementado pelo extrato da planta Mikania glomerata, na intoxicação experimental por Bothropoides jararaca. Foram usados ratos Wistar,divididos em três grupos: C - controle, VB - veneno botrópico + soro antiofídico e VBM - veneno botrópico + soro antiofídico + Mikania glomerata. As citocinas foram quantificadas, no soro e no homogenato desses animais, pelo teste ELISA, em três momentos (M1 - 30 minutos, M2 - seis horas e M3 - 24 horas após a inoculação do veneno). Os resultados obtidos evidenciaram que a intoxicação por veneno botrópico estimula principalmente a produção de IL-6 no soro e TNF-α, IL-1β, IL-6 no homogenato da pata de animais experimentalmente intoxicados. O tratamento complementar, com o extrato da planta Mikania glomerata, teve influência principalmente na produção de IL-6, IL-10 e IFN-γ no soro e IL-6, IL-1β e IFN-γ no homogenato. Porém, são necessários novos estudos com o extrato de Mikania glomerata para que se possa entender a ação dessa planta sobre a intoxicação botrópica, bem como verificar qual a melhor via para administrá-lo...

This experiment aimed to quantify the pro-inflammatory cytokine levels, including TNF-α, interleukin-1β (IL-1β) and IL-6 as well as the anti-inflammatory ones such as IL-10 and INF-γ. It was also proposed to compare the effect of the conventional treatment to a treatment in which was added the Mikania glomerata plant in the experimental intoxication using Bothropoides jararaca venom. It was used Wistar rats that were randomly divided into 3 groups: C - control; VB - Bothrops venom + antivenom serum; and VBM - Bothrops venom + antivenom serum + Mikania glomerata. Cytokines were quantified in the serum and paw homogenate using ELISA test in three different moments (M1- 30 minutes, M2- 6 hours and M3- 24 hours after venom injection). The intoxication by Bothropoides jararaca venoms mainly stimulated the production of IL-6 in the serum and TNF-α, IL-1β, IL-6 in paw homogenate of animals experimentally intoxicated. Adjunctive treatment with the extract of the Mikania glomerata plant mainly influenced the production of IL-6, IL-10 and IFN-γ in the serum and IL-6, IL1β and IFN-γ in paw homogenate. Further research is necessary with the extract of Mikania glomerata in order to understand the action of this plant on the Bothropoides poisoning and also to verify the best way to manage it...

PP020 Association between renal dysfunction and angiogenic factors in preeclampsia.

INTRODUCTION: Hyperuricemia is a common finding in preeclamptic pregnancies and proteinuria, as well as hypertension are markers of preeclampsia. Production of anti-angiogenic proteins seems to be involved in the pathophysiology of hypertension and proteinuria in preeclampsia. OBJECTIVES: The purpose of this study was to evaluate whether there is an association between renal function and changes in serum levels of angiogenic factors in preeclamptic patients. METHODS: Serum was obtained from 83 preeclamptic patients in the last trimester of pregnancy for determination of uric acid. Placental growth factor (PlGF), vascular endothelial growth factor (VEGF) and soluble form of vascular endothelial growth factor receptor (sVEGFR-1) were evaluated in serum by an enzyme immunoassay. Proteinuria was determined in a 24-h urine collection. The concentration of angiogenic factors was compared with serum uric acid levels (<6mg/dL vs ⩾6mg/dL) and with proteinuria levels (<2g vs ⩾2g). Statistical analysis was performed using non-parametric tests with significance level set at 5%. RESULTS: In 40% of women with preeclampsia serum uric acid levels were ⩾6mg/dL, and proteinuria concentration ⩾2g was detected in 41% of patients. Positive correlation was observed between uric acid and proteinuria levels (r=0.7274; p<0.0001). Serum levels of PIGF were significantly lower in preeclamptic women with serum uric acid level ⩾6mg/dL compared with women with serum uric acid <6mg/dL (median 48.46 vs 117.32pg/mL). Significant difference between proteinuria ⩾2g and <2g was detected in relation to serum levels of PIGF (median 47.58 vs 114.24pg/mL), VEGF (median 25.35 vs 33.74pg/mL) and sVEGFR-1 (median 5386 vs 4605pg/mL). CONCLUSION: Elevation in circulating uric acid as well as proteinuria in preeclamptic women is associated with an altered angiogenic balance, suggesting that angiogenic factors may be involved in kidney dysfunction.

PP061. The role of heat shock protein 60 and 70 in early- and late-onset preeclampsia differentiation.

INTRODUCTION: Preeclampsia is a human pregnancy-specific syndrome characterized by the onset of hypertension and proteinuria. These manifestations may occur before the 34th week of gestation or from this period on, being denominated early-onset or late-onset preeclampsia respectively. The etiology of both disorders seems to differ qualitatively; therefore, different strategies of prevention and treatment must be studied. OBJECTIVES: The aim of the present study is to determine whether the plasma levels of heat-shock proteins Hsp60 and Hsp70 as well as specific antibodies anti-Hsp60 and anti-Hsp70 may differentiate early-onset from late-onset preeclampsia. METHODS: We evaluated 175 pregnant women with PE (55 early-onset PE and 120 late-onset PE). Plasma was obtained from peripheral blood and Hsp60, Hsp70 as well as anti-Hsp60 and anti-Hsp70 antibody levels were determined by enzyme immunoassay. Uric acid levels were also determined in the plasma of patients. For statistical analyses, the Mann-Whitney U-test and the Spearman rank order correlation were applied with significance level set at 5%. RESULTS: Hsp70 levels obtained from early-onset PE group were significantly higher than the late-onset PE women and showed positive correlation with uric acid (r=0.4547; p=0.0028). The Hsp60 production was similar in both groups. Our results also indicate that there was no significant difference of anti-Hsp60 and anti-Hsp70 antibody levels between women with early- and late-onset PE. However,these antibody levels were high,indicating a strong relationship with the production of HSP60 and Hsp70 protein. CONCLUSION: Association between levels of Hsp70 and uric acid in plasma of patients with early-onset PE seems to reflect the oxidative stress in this group of patients. This study provides evidence that Hsp70 determination may be utilized to assess the differentiation between early- and late-onset PE. FINANCIAL SUPPORT: FAPESP 2010/09241-2.

PP062. Silibinin modulates NF-kB pathway and proinflammatory cytokines production by mononuclear cells of preeclamptic women.

INTRODUCTION: Pre-eclampsia (PE) is a complication of human pregnancy characterized by hypertension and proteinuria after 20 weeks of gestation. In addition to increased activation of monocytes and granulocytes, there is an elevated production of proinflammatory cytokines in pregnant women with PE. The nuclear transcription factor-kB (NF-kB) is present in the cells of the immune system and is responsible for transcription of genes related to inflammation. Whereas the PE is associated with intense inflammatory response, the use of substances modulating the activity of NF-kB factor could be useful in alleviating the inflammation present in these patients. Silibinin is the main component of silymarin, a polyphenolic extract obtained from fruits and seeds of Sylibum marianum with potent hepatoprotective, anti-inflammatory and anti-fibrotic activities. OBJECTIVES: The objective of this study was to assess whether silibinin modulates the activity of NF-kB and the production of inflammatory cytokines by mononuclear cells of patients with PE. METHODS: We evaluated 34 pregnant women with PE, 20 normotensive pregnant women (NT) and 15 non-pregnant women (NP). Mononuclear cells (PBMC) were obtained from peripheral blood and cultured in the presence or absence of silibinin (50uM) and stimulated with 1ug/mL of lipopolysaccharide (LPS) for 18h. The supernatant was employed for determination of tumor necrosis factor-alpha (TNF-α) and interleukin-1 (IL-1ß) by enzyme immunoassay. The cells were also cultured for 30min to perform the extraction and determination of the nuclear activity of NF-kB. RESULTS: The results showed increased endogenous activation of NF-kB in PBMC of the PE group compared with the NT and NP groups. We also observed increased production of TNF-α and IL-1ß by non-stimulated PBMC in the PE group compared with NT and NP groups. A positive correlation between NF-kB activity and endogenous production of TNF-α (r=0.6509; p=0.0047) or IL-1 b (r=0.5106; p=0.0304) was observed in the PE group. Silibinin showed an anti-inflammatory activity by inhibiting the spontaneous and LPS-stimulated NF-kB activation as well as the production of inflammatory cytokines in all the groups studied. CONCLUSION: Patients with PE showed a greater activation of PBMC cells compared with NT women. Silibinin showed modulatory activity on the inflammatory response by downregulation of NF-kB activation as well as TNF-α and IL-10 production. FINANCIAL SUPPORT: FAPESP 2010/00776-0.

PP063. TLR-4 expression and pro-inflammatory cytokine production by peripheral blood monocytes from preeclamptic women.

INTRODUCTION: Toll-like receptor (TLR)-4 and TLR-2 are involved in inflammatory response of monocytes. These cells are activated in pregnant women with preeclampsia (PE), and over-produce inflammatory cytokines. TLR4 may recognize endogenous ligands, the so-called danger signals released by damaged cells, leading to production of pro-inflammatory cytokines. OBJECTIVES: This study investigated TLR2 and TLR4 expression and cytokine production by monocytes from women with PE before and after stimulation with TLR ligands. METHODS: Monocytes (5×10(5)cell/mL) were obtained from 32 preeclamptic (PE) and 20 normotensive (NT) pregnant women in the last trimester of pregnancy. TLR2 and TLR4 expression on monocyte surface was determined by flow cytometry in non-stimulated cells, and after 18h of culture with lipopysaccharide (LPS) and peptidoglycan (PG). TNF-α, IL-10 and IL-12p70 production by these cells stimulated or not with LPS or PG was evaluated by enzyme immunoassay. Results were analyzed by non-parametric tests with significance level set at 5%. RESULTS: In the absence of stimulation, the basal TLR4 expression by monocytes detected by the median fluorescence intensity (MFI) was significantly higher in the PE group than in the NT group while no significant differences were observed between groups in relation to endogenous TLR2 expression. An increase in TLR4 MFIs was detected after monocytes from NT pregnant women were stimulated with LPS while TLR2 expression was increased after PG-stimulation. No alterations in TLR expression was detected after LPS or PG-stimulation in monocytes from patients with PE. Evaluation of endogenous cytokine levels in supernatant culture of monocytes showed higher concentrations of TNF-α and IL-12p70 in preeclamptic women in comparison with the NT group, whereas IL-10 values were significantly higher in NT pregnant women than in the PE group. In contrast, when monocytes were stimulated with the TLRs ligands LPS and PG, the release of TNF-α was significantly reduced, while IL-12p70 levels were significantly higher in women with PE compared to NT group. IL-10 production was similar in both groups studied. CONCLUSION: The basal up-regulation of TLR4 expression associated with endogenous high TNF-α and IL-12p70 production by monocytes from preeclamptic women confirms the activated profile of these cells by the disease process. These findings provide new insights into possible roles for TLRs in the pathogenesis of systemic inflammation detected in PE. FINANCIAL SUPPORT: FAPESP 2009/11924-3 and 2010/20207-0.

PP064. M1 Monocyte subpopulation is associated with pro-inflammatory cytokineproduction in pregnant women with preeclampsia.

INTRODUCTION: Monocytes from peripheral blood of pregnant women with preeclampsia are endogenously activated and secrete high levels of free radicals and inflammatory cytokines. OBJECTIVES: This study aimed at evaluating whether the inflammatory state of monocytes observed in preeclampsia is associated with the polarization of monocyte to M1 profile in peripheral blood, correlating the expression of surface receptors CD64, TLR2, TLR4, and CD163 and CD206 with cytokine production. METHODS: We studied 90 pregnant women, 30 normotensive and 60 with preeclampsia, matched for gestational age. Peripheral blood monocytes obtained from normotensive pregnant or preeclamptic pregnant women were cultured for 18h, and the expression of surface receptors on M1 inflammatory monocyte subpopulation (TLR2, TLR4 and CD64) and M2 suppressor monocyte subpopulation (CD163 and CD206) were evaluated by flow cytometry, using specific monoclonal antibodies, labeled with fluorochromes. The values were expressed as ??the mean fluorescence intensity. Moreover, the production of proinflammatory cytokines associated with M1 profile (TNF-α, IL-12p70 and IL-23) and the anti-inflammatory cytokine associated with M2 profile (IL-10) were evaluated in the monocyte supernatant of culture by enzyme immunoassay. Results were analyzed using nonparametric tests with significance level set at 5%. RESULTS: The expression of CD4 and TLR4 on monocyte surface, from women with preeclampsia was significantly higher, while the expression of CD163 and CD206 was significantly decreased compared with normotensive pregnant women, suggesting the predominance of monocyte M1 profile. Endogenous production of TNF-α, IL-12p70 and IL-23 by monocytes was increased, while synthesis of IL-10 was lower in women with preeclampsia compared with normotensive pregnant women. Positive correlations between TLR4 and CD64 (r=0.5849), TLR4 and TNF-α (r=0.5126) or TLR4 and IL-23 (r=0.8095), as well as between CD64 and TNF-α (r = 0.7133) or CD64 and IL-23 (r = 0.6051) were observed in the preeclamptic group. The results confirm the activated state of monocytes from women with preeclampsia by increased production of proinflammatory cytokines and the expression of receptors characteristic of the M1 subpopulation. CONCLUSION: This study provides evidence that monocytes from women with preeclampsia are classically activated and the systemic inflammatory environment may differentiate and polarize these cells to the M1 profile. FINANCIAL SUPPORT: CNPq, FAPESP 2009/11924-3 and 2010/20207-0.

Cell-free antigens from precocious Paracoccidioides brasiliensis culture induce a typical delayed-type hypersensitivity reaction

Cell-free antigens (CFAg) derived from Paracoccidioides brasiliensis have typically been used in immunodiffusion reactions for serodiagnosis or therapeutic follow-up of paracoccidioidomycosis patients. Thus, we investigated the usefulness of CFAg obtained from cultures at different ages, to evaluate cellular immunity by the footpad test, in experimental murine paracoccidioidomycosis. Male mice infected with P. brasiliensis 265 strain were challenged in the footpad with CFAg obtained from four- (4d CFAg) or 11-day-old cultures (11d CFAg). The increase in footpad swelling provoked by 4d CFAg and 11d CFAg was similar and showed significant difference in relation to control groups. However, the infiltrate pattern was strikingly different: 4d CFAg induced a predominant mononuclear infiltrate whereas 11d CFAg provoked a predominant polymophonuclear infiltrate. These different inflammatory patterns were associated with distinct electrophoretic characteristics. By comparison with 11d CFAg, 4d CFAg showed more numerous and intense bands, including a strong one of 43 kDa (gp43). These results suggest that CFAg derived from Pb 265 isolate can be used as a reagent to evaluate cellular immunity; however, the culture's age is critical because only young cultures are able to induce a typical mononuclear infiltrate. The efficacy of this new paracoccidioidin to assay the cellular immunity in infections caused by other P. brasiliensis isolates is under investigation.

Inhibitory effect of silibinin on tumour necrosis factor-alpha and hydrogen peroxide production by human monocytes.

Silibinin is a chemically defined flavonoid and the main active component of silymarin, a polyphenolic complex from Silybum marianum, which has anti-inflammatory, hepatoprotective and anticarcinogenic properties. Monocytes obtained from healthy individuals were incubated with silibinin to evaluate cell viability, hydrogen peroxide (H(2)O(2)) release and tumour necrosis factor-alpha (TNF-α) production by these cells. The duration of treatment and different silibinin concentrations had no significant effect on cell viability. Monocytes showed a dose-dependent inhibitory effect on H(2)O(2) release by phorbol myristate acetate-stimulated monocytes in silibinin concentrations ranging from 6.25 to 50 µg mL(-1). Significant inhibition of TNF-α production by lipopolysaccharide-stimulated monocytes was observed at concentrations of 12.5, 50 and 100 µg mL(-1) of silibinin. These results suggest that silibinin exerts antioxidant and anti-inflammatory properties on human monocytes through an inhibitory effect on H(2)O(2) release and on TNF-α production, respectively.

Inhibition of human neutrophil apoptosis by Paracoccidioides brasiliensis: role of interleukin-8.

Paracoccidioidomycosis (PCM) is a systemic mycosis caused by Paracoccidiodes brasiliensis that presents a wide spectrum of clinical manifestations. Because of the great number of neutrophils polymorphonuclear neutrophils (PMN) found in the P. brasiliensis granuloma, studies have been done to evaluate the role of these cells during the development of the infection. This fungus is found intracellularly in PMN and monocytes/macrophages, suggesting that it is capable of evading damage and surviving inside these cells. Thus, in the present study, we investigated whether P. brasiliensis can prolong the lifetime of PMN, and if this process would be related with IL-8 levels. PMN apoptosis and intracellular levels of IL-8 were analysed by flow cytometry and culture supernatants IL-8 levels were evaluated by enzyme-linked immunosorbent assay. We found that coincubation with P. brasiliensis yeast cells results in an inhibition of PMN apoptosis, which was associated with increase in IL-8 production by these cells. Cocultures treatment with monoclonal antibody anti-IL-8 reversed the inhibitory effect of P. brasiliensis on PMN apoptosis, besides to increase spontaneous apoptosis of these cells. These data show that, in contrast to other microbial pathogens that drive phagocytes into apoptosis to escape killing, P. brasiliensis can extend the lifetime of normal human PMN by inducing autocrine IL-8 production.

Microdilution procedure for antifungal susceptibility testing of Paracoccidioides brasiliensis to amphotericin b and itraconazole

In vitro tests employing microdilution to evaluate fungal susceptibility to antifungal drugs are already standardized for fermentative yeasts. However, studies on the susceptibility of dimorphic fungi such as Paracoccidioides brasiliensis employing this method are scarce. The present work introduced some modifications into antifungal susceptibility testing from the European Committee on Antimicrobial Susceptibility Testing (EUCAST), concerning broth medium and reading time, to determine minimal inhibitory concentration (MIC) of amphotericin B and itraconazole against Paracoccidioides brasiliensis. Yeast-like cells of P. brasiliensis (Pb18 strain) were tested for susceptibility to amphotericin B and itraconazole in RPMI 1640 medium, supplemented with 2 percent glucose and nitrogen source and incubated at 35ºC. The MIC of amphotericin B and itraconazole against Pb18 were respectively 0.25 µg/mL and 0.002 µg/mL. The results of minimal fungicidal concentration (MFC) showed that amphotericin B at 0.25 µg/mL or higher concentrations displayed fungicidal activity against Pb18 while itraconazole at least 0.002 µg/mL has a fungistatic effect on P. brasiliensis. In conclusion, our results showed that the method employed in the present study is reproducible and reliable for testing the susceptibility of P. brasiliensis to antifungal drugs.

Paracoccidioides brasiliensis killing by IFN-gamma, TNF-alpha and GM-CSF activated human neutrophils: role for oxygen metabolites.

Paracoccidioidomycosis, a deep mycosis endemic in Latin America, is a chronic granulomatous disease caused by the fungus Paracoccidioides brasiliensis. Phagocytic cells play a critical role against the fungus and several papers show the effects of activator and suppressive cytokines on macrophage and monocyte functions. However, the studies focusing on polymorphonuclear neutrophils (PMNs) antifungal functions are scarcer. Thus, the objective of the present paper was to assess the capacity of human PMNs to kill virulent P. brasiliensis strain in vitro, before and after priming with different cytokines. Moreover, the involvement of oxygen metabolites in this activity was evaluated. Nonactivated cells failed to exhibit antifungal activity. However, when these cells were IFN-gamma, TNF-alpha or GM-CSF activated, a significative fungicidal activity was detected. This process was significantly inhibited when P. brasiliensis challenge occurred in presence of catalase (CAT - a scavenger of H2O2) and superoxide dismutase (SOD - a scavenger of superoxide anion). From these results it is concluded that cytokines activation is required for P. brasiliensis killing by human PMNs, and that H2O2 and superoxide anion participate as effectors molecules in this process.

Interleukin-15: its role in microbial infections

Interleukin-15 (IL-15) is a pleiotropic cytokine which regulates the proliferation, survival and the secretory activities of many distinct cell types in the body. This cytokine is produced by macrophages and many other cell types in response to infectious agents; it controls growth and differentiation of T and B lymphocytes, activation of Natural Killer (NK) and phagocytic cells, and contributes to the homeostasis of the immune system. The present review focuses on the biological and modulatory effects of IL-15 in microbial infections and shows that this cytokine may play a role in the host defense against infections by inducing activation of effector cells from both innate and adaptive immune system.(AU)

Cytokine profile and clinical metabolic alterations in HIV-1 infected individuals with and without lipodistrophy

The extensive use of Highly Active Antiretroviral Therapy (HAART) has transformed HIV infection into a chronic condition. Thus, metabolic alterations including lipodystrophy and dyslipidemia have been associated with the use of such medications. The objective of the present study was to analyze clinical metabolic alterations and the profile of TNF-alpha, IFN-Y, IL-2, IL-10, and TNF-alpha type II soluble receptor in serum of HIV-1 individuals with and without lipodystrophy. Eighty-four adults were evaluated, 42 males and 42 females, mean age 37 years, and HAART time of at least 15 months. Two groups were formed, G1: 42 individuals with lipodystrophy, and G2: 42 without lipodistropy. From the HAART used, stavudine was more associated with the lipodystrophy group and zidovudine with the non-lipodystrophy group. CD4 and CD8 values, viral load, glucose, albumin, and lipids were not different between groups, except for triglycerides, which were high in the lipodystrophy group, and HDL, whose concentration was reduced in G1. TNF-alpha, TNF-RII, and IL-10 profiles were high and had positive correlation; IL-2 and IFN-gamma had reduced levels in the lipodystrophy group. High TNF-alpha and its receptor levels seem to be associated with lipodystrophy development in individuals under HAART therapy.

Virulence attenuation and phenotypic variation of Paracoccidioides brasiliensis isolates obtained from armadillos and patients.

Paracoccidioides brasiliensis is the etiological agent of paracoccidioidomycosis, the most important systemic mycosis in Latin America. The virulence profiles of five isolates of P. brasiliensis were studied in two different moments and correlated with some colonial phenotypic aspects. We observed a significant decrease in the virulence and an intense phenotypic variation in the mycelial colony. The recognition of all ranges of phenotypic and virulence variation of P. brasiliensis, as well as its physiological and genetic basis, will be important for a better comprehension of its pathogenic and epidemiological features.

TNF-alpha activates human monocytes for Paracoccidioides brasiliensis killing by an H2O2-dependent mechanism.

Human monocytes activated by recombinant tumor necrosis factor alpha (TNF-alpha) exhibited significant fungicidal activity on the yeast cells of a highly virulent strain of Paracoccidioides brasiliensis. This process was significantly inhibited in the presence of catalase (CAT - a scavenger of H2O2), but not in the presence of superoxide-dismutase (SOD - a scavenger of superoxide anion) or NG-monomethyl-L-arginine (NG-MMLA - a nitric oxide inhibitor). Furthermore, there was a direct association between the intracellular killing of the fungus and the production of H2O2 by activated cells. These results strongly suggest a role for H2O2 in the killing of highly virulent strains of P. brasiliensis by TNF-alpha-activated human monocytes.