Healthcare workers exposed to COVID-19 patients present an inflammatory status and Th2/Th17/Th22 immune profile: findings from before vaccine application in Brazil.

Healthcare workers present an increased risk of contagion for the SARS-CoV-2 virus due to their labor exposure. Here, we describe the clinical, laboratory, and immunological characteristics of healthcare workers, before vaccine application, exposed to SARS-CoV-2-infected patients. We collected sociodemographic, clinical, and laboratory information from 50 professionals who worked during the COVID-19 pandemic at the Clinical Hospital of the Northwest in Brazil. The results showed that most workers are women, over 50 years old, and worked as nursing technicians. Approximately 56% of workers were positive for a previous infection by RT-PCR and/or anti-SARS-CoV-2-immunoglobulin tests. Increased levels of hematocrit, neutrophils, NK lymphocytes, and fibrinogen, were found in positive healthcare workers, suggesting a light inflammatory status. The immunological findings showed an increase in IL-17 production and a Th2/Th17/Th22 profile followed by high serology for anti-SARS-CoV-2 IgM and IgG. Those data reveal the importance of studies with healthcare workers to investigate if the continuous exposition to the virus may result in chronic activation of the immune system and/or pulmonary inflammation in this target group.

Memory elicitation, T-cell response and antibody production: an independent study of an inactivated entire virus vaccine (Coronavac).

Health professionals working to mitigate the COVID-19 pandemic are one of the main risk groups for the disease, being prioritized for vaccination. Considering this, the aim of this study was to analyze the immune response of these professionals immunized with CoronaVac in the first and second doses. Blood samples were collected after the first and second doses of the vaccine (CoronaVac) and used to investigate hematological and biochemical parameters, analysis of immunoglobulin production, cytokines, and gene expression profile, as well as the identification of subsets of immune cells. Post-first dose immunological phenotypic memory (CD27+) profiles (T CD4+, TCD8+ and CD19+) showed a significant increase, as did Monocyte APCs (CD80+HLA-DR+) in relation to the second dose. The cytokines IL-2, IL-6 and IFN-° showed increased values in relation to the other analyzed cytokines. The Th2/Th17 profile in the second dose was characterized by gene expression analysis. The production of IgM and IgG after vaccination showed statistically significant values in the comparison between doses. CoronaVac showed activation of APCs monocytes, memory response of T and B lymphocytes, with immunoglobulins production. This set of responses is characterized by the Th2/Th17 immunological profile.

In vitro and in vivo effects of P-MAPA immunomodulator on schistosomiasis.

Schistosomiasis is an infectious disease caused by helminth parasites of the genus Schistosoma; it is transmitted in over 78 countries. The main strategy for schistosomiasis control is treatment of infected people with praziquantel (PZQ). As PZQ-resistant strains have emerged, new anti-schistosomal agents have become necessary. We evaluated the in vitro and in vivo effect of P-MAPA, an aggregated polymer of protein magnesium ammonium phospholinoleate-palmitoleate anhydride with immunomodulatory properties; it is produced by Aspergillus oryzae fermentation. In vitro, P-MAPA (5, 50, and 100 µg/mL) damaged the Schistosoma mansoni tegument, causing thorn losses and tuber destruction in male worms and peeling and erosion in females after 24-h incubation. In vivo, P-MAPA (5 and 100 mg/kg, alone and combined with PZQ - 50 mg/kg) reduced the number of eggs by up to 69.20% in the liver and 88.08% in the intestine. Furthermore, granulomas were reduced up to 83.13%, and there was an increase in the number of dead eggs and a reduction of serum aspartate aminotransferase levels. These data suggest that P-MAPA activity can help improve schistosomiasis treatment and patients' quality of life.

The P-MAPA Immunomodulator Partially Prevents Apoptosis Induced by Zika Virus Infection in THP-1 Cells.

BACKGROUND: Zika virus is an emerging arbovirus of global importance. ZIKV infection is associated with a range of neurological complications such as the Congenital Zika Syndrome and Guillain Barré Syndrome. Despite the magnitude of recent outbreaks, there is no specific therapy to prevent or to alleviate disease pathology. OBJECTIVE: To investigate the role of P-MAPA immunomodulator in Zika-infected THP-1 cells. METHODS: THP-1 cells were subjected to Zika virus infection (Multiplicity of Infection = 0.5) followed by treatment with P-MAPA for until 96 hours post-infection. After that, the cell death was analyzed by annexin+/ PI+ and caspase 3/ 7+ staining by flow cytometry. In addition, virus replication and cell proliferation were accessed by RT-qPCR and Ki67 staining, respectively. RESULTS: We demonstrate that P-MAPA in vitro treatment significantly reduces Zika virus-induced cell death and caspase-3/7 activation on THP-1 infected cells, albeit it has no role in virus replication and cell proliferation. CONCLUSION: Our study reveals that P-MAPA seems to be a satisfactory alternative to inhibit the effects of Zika virus infection in mammalian cells.

Entomological surveys of Lutzomyia flaviscutellata and other vectors of cutaneous leishmaniasis in municipalities with records of Leishmania amazonensis within the Bragança region of Pará State, Brazil.

In southeast Amazon, Lutzomyia (Nyssomyia) flaviscutellata is the incriminated vector of Leishmania (Leishmania) amazonensis, a causative agent of zoonotic cutaneous leishmaniasis (CL). The optimal methods for surveying Lu. flaviscutellata were investigated in the Bragança region, northeast Pará State, Brazil, selected for the presence of Le. amazonensis. The performances of modified Disney traps and CDC light traps were compared in four ecotopes within and around four village transects during the wet and dry seasons. The physiological age of female sand flies was estimated and natural infection by flagellates was evaluated by dissection. Disney traps were better for detecting the presence of Lu. flaviscutellata, while CDC traps performed well for detecting Lutzomyia (Nyssomyia) antunesi, suspected vector of Leishmania lindenbergi. The former was more abundant during the wet season, when female flies were naturally infected with Le. amazonensis. These findings identified the environments of local transmission. In order to improve surveys of Lu. flaviscutellata as part of integrated epidemiological surveillance of CL, our recommendations include focusing vector surveys with Disney traps on forest fragments where people work, during the seasonal peak of the vector. Further field studies are required to make model-based predictions of seasonal variations in the vectorial capacity of vector populations.

Probiotics modulate gut microbiota and improve insulin sensitivity in DIO mice.

Obesity and type 2 diabetes are characterized by subclinical inflammatory process. Changes in composition or modulation of the gut microbiota may play an important role in the obesity-associated inflammatory process. In the current study, we evaluated the effects of probiotics (Lactobacillus rhamnosus, L. acidophilus and Bifidobacterium bifidumi) on gut microbiota, changes in permeability, and insulin sensitivity and signaling in high-fat diet and control animals. More importantly, we investigated the effects of these gut modulations on hypothalamic control of food intake, and insulin and leptin signaling. Swiss mice were submitted to a high-fat diet (HFD) with probiotics or pair-feeding for 5 weeks. Metagenome analyses were performed on DNA samples from mouse feces. Blood was drawn to determine levels of glucose, insulin, LPS, cytokines and GLP-1. Liver, muscle, ileum and hypothalamus tissue proteins were analyzed by Western blotting and real-time polymerase chain reaction. In addition, liver and adipose tissues were analyzed using histology and immunohistochemistry. The HFD induced huge alterations in gut microbiota accompanied by increased intestinal permeability, LPS translocation and systemic low-grade inflammation, resulting in decreased glucose tolerance and hyperphagic behavior. All these obesity-related features were reversed by changes in the gut microbiota profile induced by probiotics. Probiotics also induced an improvement in hypothalamic insulin and leptin resistance. Our data demonstrate that the intestinal microbiome is a key modulator of inflammatory and metabolic pathways in both peripheral and central tissues. These findings shed light on probiotics as an important tool to prevent and treat patients with obesity and insulin resistance.

Species-specific ecological niche modelling predicts different range contractions for Lutzomyia intermedia and a related vector of Leishmania braziliensis following climate change in South America.

BACKGROUND: Before 1996 the phlebotomine sand fly Lutzomyia neivai was usually treated as a synonym of the morphologically similar Lutzomyia intermedia, which has long been considered a vector of Leishmania braziliensis, the causative agent of much cutaneous leishmaniasis in South America. This report investigates the likely range changes of both sand fly species in response to a stabilisation climate change scenario (RCP4.5) and a high greenhouse gas emissions one (RCP8.5). METHODS: Ecological niche modelling was used to identify areas of South America with climates currently suitable for each species, and then the future distributions of these climates were predicted based on climate change scenarios. Compared with the previous ecological niche model of L. intermedia (sensu lato) produced using the GARP algorithm in 2003, the current investigation modelled the two species separately, making use of verified presence records and additional records after 2001. Also, the new ensemble approach employed ecological niche modelling algorithms (including Maximum Entropy, Random Forests and Support Vector Machines) that have been widely adopted since 2003 and perform better than GARP, as well as using a more recent climate change model (HadGEM2) considered to have better performance at higher resolution than the earlier one (HadCM2). RESULTS: Lutzomyia intermedia was shown to be the more tropical of the two species, with its climatic niche defined by higher annual mean temperatures and lower temperature seasonality, in contrast to the more subtropical L. neivai. These different latitudinal ranges explain the two species' predicted responses to climate change by 2050, with L. intermedia mostly contracting its range (except perhaps in northeast Brazil) and L. neivai mostly shifting its range southwards in Brazil and Argentina. This contradicts the findings of the 2003 report, which predicted more range expansion. The different findings can be explained by the improved data sets and modelling methods. CONCLUSIONS: Our findings indicate that climate change will not always lead to range expansion of disease vectors such as sand flies. Ecological niche models should be species specific, carefully selected and combined in an ensemble approach.

Evolution to permanent or transient conditions in children with positive neonatal TSH screening tests in Sergipe, Brazil.

OBJECTIVES: To assess the evolution to permanent or transient conditions in children with positive neonatal TSH tests in Sergipe, Brazil, from 2004 to 2010. SUBJECTS AND METHODS: Out of 193,794 screened newborns, 713 presented a neonatal TSH level higher than the local cutoff (5.2 µU/mL). From the confirmatory serum TSH values, the children were diagnosed with initial congenital hypothyroidism (CH) or suspect CH. From the evolution, they were classified as permanent CH, hyperthyrotropinemia, or transient TSH elevation. The mean incidence of each final condition was calculated for the total period of time. RESULTS: The initial diagnosis included 37 CH (18.1%) and 167 suspect CH (81.9%) cases. The final diagnosis included 46 cases of permanent CH (22.5%), 56 of hyperthyrotropinemia (27.5%), and 102 of transient TSH elevation (50.0%). Out of the 37 cases of initial CH, 23 (62.2%) had permanent CH, nine (24.3%) had hyperthyrotropinemia, and five (13.5%) had transient TSH elevation. Out of the 167 suspect CH cases, 23 (13.8%) had permanent CH, 47 (28.1%) had hyperthyrotropinemia and 97 (58.1%) had transient TSH elevation. The mean incidence after the follow up was 1:4,166 for permanent CH, 1:3,448 for hyperthyrotropinemia, and 1:1,887 for transient TSH elevation. Eighty-six percent of the children with an initial diagnosis of CH and 41.9% with suspect CH had a permanent condition (CH or hyperthyrotropinemia). CONCLUSIONS: The follow-up of children with an initial diagnosis of CH or suspect CH is necessary to determine whether the disorder is permanent because predicting the evolution of the condition is difficult.

Evolution to permanent or transient conditions in children with positive neonatal TSH screening tests in Sergipe, Brazil

ABSTRACT Objectives To assess the evolution to permanent or transient conditions in children with positive neonatal TSH tests in Sergipe, Brazil, from 2004 to 2010. Subjects and methods Out of 193,794 screened newborns, 713 presented a neonatal TSH level higher than the local cutoff (5.2 µU/mL). From the confirmatory serum TSH values, the children were diagnosed with initial congenital hypothyroidism (CH) or suspect CH. From the evolution, they were classified as permanent CH, hyperthyrotropinemia, or transient TSH elevation. The mean incidence of each final condition was calculated for the total period of time. Results The initial diagnosis included 37 CH (18.1%) and 167 suspect CH (81.9%) cases. The final diagnosis included 46 cases of permanent CH (22.5%), 56 of hyperthyrotropinemia (27.5%), and 102 of transient TSH elevation (50.0%). Out of the 37 cases of initial CH, 23 (62.2%) had permanent CH, nine (24.3%) had hyperthyrotropinemia, and five (13.5%) had transient TSH elevation. Out of the 167 suspect CH cases, 23 (13.8%) had permanent CH, 47 (28.1%) had hyperthyrotropinemia and 97 (58.1%) had transient TSH elevation. The mean incidence after the follow up was 1:4,166 for permanent CH, 1:3,448 for hyperthyrotropinemia, and 1:1,887 for transient TSH elevation. Eighty-six percent of the children with an initial diagnosis of CH and 41.9% with suspect CH had a permanent condition (CH or hyperthyrotropinemia). Conclusions The follow-up of children with an initial diagnosis of CH or suspect CH is necessary to determine whether the disorder is permanent because predicting the evolution of the condition is difficult.

Ecological Niche Modelling Predicts Southward Expansion of Lutzomyia (Nyssomyia) flaviscutellata (Diptera: Psychodidae: Phlebotominae), Vector of Leishmania (Leishmania) amazonensis in South America, under Climate Change.

Vector borne diseases are susceptible to climate change because distributions and densities of many vectors are climate driven. The Amazon region is endemic for cutaneous leishmaniasis and is predicted to be severely impacted by climate change. Recent records suggest that the distributions of Lutzomyia (Nyssomyia) flaviscutellata and the parasite it transmits, Leishmania (Leishmania) amazonensis, are expanding southward, possibly due to climate change, and sometimes associated with new human infection cases. We define the vector's climatic niche and explore future projections under climate change scenarios. Vector occurrence records were compiled from the literature, museum collections and Brazilian Health Departments. Six bioclimatic variables were used as predictors in six ecological niche model algorithms (BIOCLIM, DOMAIN, MaxEnt, GARP, logistic regression and Random Forest). Projections for 2050 used 17 general circulation models in two greenhouse gas representative concentration pathways: "stabilization" and "high increase". Ensemble models and consensus maps were produced by overlapping binary predictions. Final model outputs showed good performance and significance. The use of species absence data substantially improved model performance. Currently, L. flaviscutellata is widely distributed in the Amazon region, with records in the Atlantic Forest and savannah regions of Central Brazil. Future projections indicate expansion of the climatically suitable area for the vector in both scenarios, towards higher latitudes and elevations. L. flaviscutellata is likely to find increasingly suitable conditions for its expansion into areas where human population size and density are much larger than they are in its current locations. If environmental conditions change as predicted, the range of the vector is likely to expand to southeastern and central-southern Brazil, eastern Paraguay and further into the Amazonian areas of Bolivia, Peru, Ecuador, Colombia and Venezuela. These areas will only become endemic for L. amazonensis, however, if they have competent reservoir hosts and transmission dynamics matching those in the Amazon region.

Translational research into gut microbiota: new horizons on obesity treatment: updated 2014.

Obesity is currently a pandemic of worldwide proportions affecting millions of people. Recent studies have proposed the hypothesis that mechanisms not directly related to the human genome could be involved in the genesis of obesity, due to the fact that, when a population undergoes the same nutritional stress, not all individuals present weight gain related to the diet or become hyperglycemic. The human intestine is colonized by millions of bacteria which form the intestinal flora, known as gut flora. Studies show that lean and overweight human may present a difference in the composition of their intestinal flora; these studies suggest that the intestinal flora could be involved in the development of obesity. Several mechanisms explain the correlation between intestinal flora and obesity. The intestinal flora would increase the energetic extraction of non-digestible polysaccharides. In addition, the lipopolysaccharide from intestinal flora bacteria could trigger a chronic sub-clinical inflammatory process, leading to obesity and diabetes. Another mechanism through which the intestinal flora could lead to obesity would be through the regulation of genes of the host involved in energy storage and expenditure. In the past five years data coming from different sources established causal effects between intestinal microbiota and obesity/insulin resistance, and it is clear that this area will open new avenues of therapeutic to obesity, insulin resistance and DM2.

Translational research into gut microbiota: new horizons on obesity treatment: updated 2014

Obesity is currently a pandemic of worldwide proportions affecting millions of people. Recent studies have proposed the hypothesis that mechanisms not directly related to the human genome could be involved in the genesis of obesity, due to the fact that, when a population undergoes the same nutritional stress, not all individuals present weight gain related to the diet or become hyperglycemic. The human intestine is colonized by millions of bacteria which form the intestinal flora, known as gut flora. Studies show that lean and overweight human may present a difference in the composition of their intestinal flora; these studies suggest that the intestinal flora could be involved in the development of obesity. Several mechanisms explain the correlation between intestinal flora and obesity. The intestinal flora would increase the energetic extraction of non-digestible polysaccharides. In addition, the lipopolysaccharide from intestinal flora bacteria could trigger a chronic sub-clinical inflammatory process, leading to obesity and diabetes. Another mechanism through which the intestinal flora could lead to obesity would be through the regulation of genes of the host involved in energy storage and expenditure. In the past five years data coming from different sources established causal effects between intestinal microbiota and obesity/insulin resistance, and it is clear that this area will open new avenues of therapeutic to obesity, insulin resistance and DM2.

Alzheimer-associated Aß oligomers impact the central nervous system to induce peripheral metabolic deregulation.

Alzheimer's disease (AD) is associated with peripheral metabolic disorders. Clinical/epidemiological data indicate increased risk of diabetes in AD patients. Here, we show that intracerebroventricular infusion of AD-associated Aß oligomers (AßOs) in mice triggered peripheral glucose intolerance, a phenomenon further verified in two transgenic mouse models of AD. Systemically injected AßOs failed to induce glucose intolerance, suggesting AßOs target brain regions involved in peripheral metabolic control. Accordingly, we show that AßOs affected hypothalamic neurons in culture, inducing eukaryotic translation initiation factor 2α phosphorylation (eIF2α-P). AßOs further induced eIF2α-P and activated pro-inflammatory IKKß/NF-κB signaling in the hypothalamus of mice and macaques. AßOs failed to trigger peripheral glucose intolerance in tumor necrosis factor-α (TNF-α) receptor 1 knockout mice. Pharmacological inhibition of brain inflammation and endoplasmic reticulum stress prevented glucose intolerance in mice, indicating that AßOs act via a central route to affect peripheral glucose homeostasis. While the hypothalamus has been largely ignored in the AD field, our findings indicate that AßOs affect this brain region and reveal novel shared molecular mechanisms between hypothalamic dysfunction in metabolic disorders and AD.

Modulation of double-stranded RNA-activated protein kinase in insulin sensitive tissues of obese humans.

OBJECTIVE: The double-stranded RNA-dependent protein kinase (PKR) was recently implicated in regulating molecular integration of nutrient- and pathogen-sensing pathways in obese mice. However, its modulation in human tissues in situations of insulin resistance has not been investigated. The present study was performed to first determine the tissue expression and phosphorylation levels of PKR in the liver, muscle, and adipose tissue in obese humans, and also the modulation of this protein in the adipose tissue of obese patients after bariatric surgery. DESIGN AND METHODS: Eleven obese subjects who were scheduled to undergo Roux-en-Y Gastric Bypass Procedure participated in this study. Nine apparently healthy lean subjects as a control group were also included. RESULTS: Our data show that PKR is activated in liver, muscle, and adipose tissue of obese humans and, after bariatric surgery, there is a clear reduction in PKR activation accompanied by a decrease in protein kinase-like endoplasmic reticulum kinase, c-Jun N-terminal kinase, inhibitor of kappa ß kinase, and insulin receptor substrate-1 serine 312 phosphorylation in subcutaneous adipose tissue from these patients. CONCLUSION: Thus, it is proposed that PKR is an important mediator of obesity-induced insulin resistance and a potential target for the therapy.

Acute exercise induces a phenotypic switch in adipose tissue macrophage polarization in diet-induced obese rats.

OBJECTIVE: It has become clear that exercise may be a useful therapy in the insulin resistance treatment, as it has anti-inflammatory effects and improves insulin sensitivity. However, it remains uncertain whether exercise affects the adipocytes or infiltrated macrophages. Thus, the aim was to investigate the effects of acute exercise on the inflammatory status and insulin signaling of the white adipose tissue (WAT) fractions (stromal-vascular fraction [SVF] and adipocytes). DESIGN AND METHODS: The effect of acute swimming exercise was investigated on insulin sensitivity, insulin signaling, inflammatory pathways in the WAT fractions of high-fat fed Wistar rats. Additionally, macrophage infiltration and polarization were analyzed in the WAT. RESULTS: Acute exercise can improve insulin signaling in WAT fractions, along with a phenotypic switch from M1- to M2-macrophages in obese rats, as indicated by a marked increase in macrophage galactose-type C-type lectin 1-positive cells in WAT was observed. Additionally, exercise promoted a reduction in circulating levels of lipopolysaccharide, and toll-like receptor 4 activity along with TNF-alpha, IL-1-beta and MCP-1 mRNA levels in WAT fractions. CONCLUSIONS: These data suggest that acute exercise improves insulin signaling in the WAT, at least in part by inducing macrophage polarization toward the M2-state.

Targeted disruption of inducible nitric oxide synthase protects against aging, S-nitrosation, and insulin resistance in muscle of male mice.

Accumulating evidence has demonstrated that S-nitrosation of proteins plays a critical role in several human diseases. Here, we explored the role of inducible nitric oxide synthase (iNOS) in the S-nitrosation of proteins involved in the early steps of the insulin-signaling pathway and insulin resistance in the skeletal muscle of aged mice. Aging increased iNOS expression and S-nitrosation of major proteins involved in insulin signaling, thereby reducing insulin sensitivity in skeletal muscle. Conversely, aged iNOS-null mice were protected from S-nitrosation-induced insulin resistance. Moreover, pharmacological treatment with an iNOS inhibitor and acute exercise reduced iNOS-induced S-nitrosation and increased insulin sensitivity in the muscle of aged animals. These findings indicate that the insulin resistance observed in aged mice is mainly mediated through the S-nitrosation of the insulin-signaling pathway.

Hepatocyte growth factor plays a key role in insulin resistance-associated compensatory mechanisms.

Insulin resistance is present in obesity and in type 2 diabetes and is associated with islet cell hyperplasia and hyperinsulinemia, but the driving forces behind this compensatory mechanism are incompletely understood. Previous data have suggested the involvement of an unknown circulating insulin resistance-related ß-cell growth factor. In this context, looking for candidates to be a circulating factor, we realized that hepatocyte growth factor (HGF) is a strong candidate as a link between insulin resistance and increased mass of islets/hyperinsulinemia. Our approach aimed to show a possible cause-effect relationship between increase in circulating HGF levels and compensatory islet hyperplasia/hyperinsulinemia by showing the strength of the association, whether or not is a dose-dependent response, the temporality, consistency, plausibility, and reversibility of the association. In this regard, our data showed: 1) a strong and consistent correlation between HGF and the compensatory mechanism in three animal models of insulin resistance; 2) HGF increases ß-cell mass in a dose-dependent manner; 3) blocking HGF shuts down the compensatory mechanisms; and 4) an increase in HGF levels seems to precede the compensatory response associated with insulin resistance, indicating that these events occur in a sequential mode. Additionally, blockages of HGF receptor (Met) worsen the impaired insulin-induced insulin signaling in liver of diet-induced obesity rats. Overall, our data indicate that HGF is a growth factor playing a key role in islet mass increase and hyperinsulinemia in diet-induced obesity rats and suggest that the HGF-Met axis may have a role on insulin signaling in the liver.