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.

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...

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.

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.

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.

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)

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.

Antibody and cytokine seerum levels in patients subjected to anti-rabies prophylaxis with serum-vaccination

Rabies is considered a fatal disease once clinical symptoms have developed. The aim of this study was to evaluate epidemiological aspects and immune response in patients attacked by domestic and wild animals and subjected to post-exposure rabies treatment with equine serum and associated vaccine. Thirty-three patients were evaluated; they were between 13 and 65 years old, 75.8% were male and 24.2% female, and from the Botucatu neighborhood. Twenty healthy control individuals with the same age range were also studied. Specific antibodies to equine immunoglobulins and IFN-g, IL-2, IL-4, and IL-10 production were evaluated by ELISA. IgM, IgE, IgG and subclasses, and rabies virus antibodies serum levels were determined by nephelometry and seroneutralization methods, respectively. No anaphylactic or serum sickness allergic reactions were observed in patients after treatment. Anti-equine IgG levels were significantly higher than those of IgM after 14 and 28 days of treatment. Protective antibodies to rabies virus > 0.5 UI/ml were detected in 84.6% and 75% of patients at days 14 and 28, respectively. IFN-g, IL-2 and IL-10 levels in patients before and 48h after treatment were significantly higher than in controls suggesting that both Th1 and Th2 cells were activated in the patients. Serum IgM levels were higher at day 14, and IgG2 and IgE levels were higher at day 28 of treatment. These results suggest that post-exposure rabies treatment in humans induces significant alterations in patient immune response characterized by increased levels of cytokines, serum levels of specific rabies virus antibodies, and the equine serum components employed in the treatment

Evolution and prophylaxis of human rabies

Rabies is a viral acute encephalitis of progressive and fatal outcome, particular of hot-blooded animals, and accidentally affecting men. Since it is a zoonosis with different animal species acting as a reservoir in the nature, this disease is a great public health problem in several countries in development. Prophylactic treatments for human rabies started in 1885 with Louis Pasteur, and developed in order to provide higher protection and lower incidence of side effects. Today, treatments of pre and post-exposure to the virus are well established, with excellent results of protection for individuals exposed to animals potentially contaminated by the rabies virus. These treatments consist of utilising the vaccine isolatedly or in combination with equine immunoglobulin, what contributes, in an important way, to the decrease in the number of cases of rabies.(AU)

Effect of bacillus of Calmette-Guerin, avridine and Propionibacterium acnes as immunomodulators on rabies in mice

Avaliou-se a resposta imune celular e humoral de camundongos inoculados com virus rabico de rua e submetidos aos imunomoduladores Onco-BCG, avridina e Propionibacterium acnes. Os animais submetidos ao tratamento com P. acnes apresentaram um maior percentual de sobrevivencia quando comparados aos dos demais tratamentos. Foram observados menores niveis de IFN-gama nos animais infectados, sugerindo imunossupressao viral. O teste do Coxim Plantar nao foi eficaz para a deteccao da resposta de hipersensibilidade retardada na metodologia utilizada, contrariamente ao MIF. A sobrevivencia dos animais nao apresentou correlacao com os niveis de anticorpos soroneutralizantes, concentracao de IFN-gama e resposta ao MIF

Use of an ELISA assay to evaluate venom, antivenom, IgG and IgM human antibody levels in serum and cerebrospinal fluid from patients bitten by Crotalus durissus terrificus in Brazil

A sandwich-type ELISA technique for specific and sensitive detection of Crotalus durissus terrificus venom antigens, horse-antivenom, human IgG and IgM antibodies was set up. Sixteen patients, 13 males and 3 females aged between 13 to 63 years (mean 33 ñ 15) bitten by Crotalus durissus terrificus snakes were studied. Of the 15 patiens, 6 had previously received anti-Crotalus venom and no seric venom was detected. For the other 9 patients studied, the venom levels ranged from 2 to 108mg/ml according to the severity of each case. Seric antivenom was detected up to 44 days after the bite. IgM human antibody levels against Crotalus venom were higher between 3 and 18 days after specific treatment. IgG human antibody levels against Crotalus venom were detected between 30 and 90 days after envenoming. Venom and antivenom levels in cerebrospinal fluid were not observed 24 h after the bite. This suggests that neither the venom nor the antivenom is capable of crossing the blood-brain barrier. In addition, when either venom or the antivenom is presented to the immune system cells an immune response is prepared.

Intradermo-reaçäo cervical para diagnóstico de infecçöes por Eurytrema sp em bovinos / Cervical, intradermal reaction for diagnosis of Eurytrema sp infection in cattle

Foram realizadas intradermo-reaçöes (IDR) cervicais em 101 bovinos, machos e fêmeas, que receberam, simultaneamente e ao acaso, em sete áreas adjacentes, 0,1ml de salina e igual volume de um extrato antigênico de Eurytrema sp, nas seguintes concentraçöes de proteína: 25ug/ml, 50ug/ml, 100ug/ml, 250ug/ml, 500ug/ml e 1mg/ml. Feitas todas as injeçöes intradérmicas e, ao final de 30min, com auxílio de uma régua milimetrada, de cada pápula produzida foram medidos os dois diâmetros maiores, extraídas as médias (diâmetros inicial, Di e final,Df) e calculada a diferença Df-Di. No dia seguinte acompanhava-se o abate de cada animal a fim de se verificar, por meio de exames macroscópicos dos respectivos pâncreas, se eram ou näo parasitados por Eurytrema sp. Concluiu-se, entäo, que o extrato salino bruto do trematódeo, utilizado como antígeno, deverá conter, no momento de sua utilizaçäo, concentraçäo de proteínas equivalente a 250ug/ml e, respectivamente, serem consideradas positivas e negativas as IDR que apresentarem Df-Di>2,5mm e Df-Di<2,5mm

Studies of natural killer cells in pregnancy-induced hypertension

The number and activity of natural killer (NK) cells were studied in 20 patients with pregnancy-induced hypertension (PIH), 15 uncomplicated pregnant women and 16 healthy non-pregnant women. All the pregnant women were evaluated during the third trimester of gestation. Peripheral blood NK cells were detected with monoclonal antibodies by indirect immunofluorescence and cytotoxic activity was measured using a single-cell assau against K562 target cells, Hypertensive pregnant women had an increased number of circulating NK cells associated with a significant decrease of NK activity. The cytotoxic activity was significantly lower in normal pregnant and PIH women when compared with non-pregnant controls. The onset of immune NK cells in peripheral blood and the impairment of their cytotoxic activity in PIH patients may be associated with hormones and immunosuppresive substances produced by tissues occurring at the maternal-fetal interface