HSP60: Issues and Insights on Its Therapeutic Use as an Immunoregulatory Agent

Heat shock proteins 60 (HSP60) is one of the most well studied member of the HSP family. Although found to be a target self antigen in pathological autoimmunity and HSP60-reactive T and B cells are part of immune responses in several infectious diseases, there is consistent experimental evidence that HSP60 displays dominant immunoregulatory properties. There are a series of reports on animal models showing that the administration of HSP60 can modulate inflammatory diseases. However, HSP60 has both immune-regulatory and inflammatory properties placing it as an essentially homeostatic antigen, but with potentially harmful effects as well. There have been a series of reports on the successful use of HSP60 and its peptides as immune-modulatory agent for several models of autoimmune diseases and in some clinical trials as well. We believe that the potential risks of HSP60 as a therapeutic agent can be controlled by addressing important factors determining its effects. These factors would be route of administration, appropriate peptides, time point of administration in the course of the disease, and possible association with other modulatory agents

Oral Tolerance: Therapeutic Implications for Autoimmune Diseases

Oral tolerance is classically defined as the suppression of immune responses to antigens (Ag) that have been administered previously by the oral route. Multiple mechanisms of tolerance are induced by oral Ag. Low doses favor active suppression, whereas higher doses favor clonal anergy/deletion. Oral Ag induces Th2 (IL-4/IL-10) and Th3 (TGF-β) regulatory T cells (Tregs) plus CD4+CD25+ regulatory cells and LAP+T cells. Induction of oral tolerance is enhanced by IL-4, IL-10, anti-IL-12, TGF-β, cholera toxin B subunit (CTB), Flt-3 ligand, anti-CD40 ligand and continuous feeding of Ag. In addition to oral tolerance, nasal tolerance has also been shown to be effective in suppressing inflammatory conditions with the advantage of a lower dose requirement. Oral and nasal tolerance suppress several animal models of autoimmune diseases including experimental allergic encephalomyelitis (EAE), uveitis, thyroiditis, myasthenia, arthritis and diabetes in the nonobese diabetic (NOD) mouse, plus non-autoimmune diseases such as asthma, atherosclerosis, colitis and stroke. Oral tolerance has been tested in human autoimmune diseases including MS, arthritis, uveitis and diabetes and in allergy, contact sensitivity to DNCB, nickel allergy. Positive results have been observed in phase II trials and new trials for arthritis, MS and diabetes are underway. Mucosal tolerance is an attractive approach for treatment of autoimmune and inflammatory diseases because of lack of toxicity, ease of administration over time and Ag-specific mechanism of action. The successful application of oral tolerance for the treatment of human diseases will depend on dose, developing immune markers to assess immunologic effects, route (nasal versus oral), formulation, mucosal adjuvants, combination therapy and early therapy

Self-control feeding in children

Introduction: Overweight and childhood obesity are a public health problem. Therefore, it is fundamental to intervene in the factors at the behavioural level that can lead to changes. Objectives: To evaluate children’s food self-control and to relate it to gender, the phratry, nutritional status and food preferences. To verify the influence of the nutritionist (about food literacy and the nutritional education) in the children’s self-control and dietary preferences. Methods: The study was carried out in a sample of 66 children, aged between 4 and 6 years old, from four kindergarten in the district of Leiria. The criteria used for the analysis was: food self-control, food preferences, nutritional status, food literacy of the head of education and the effect of food education. The statistical treatment of data was performed using SPSS ß version 21 software. Results: In the analysed sample, mainly female (53.0%), 57.6% of the children were not the first children and had normal nutritional status (77.3%); 19.7% were overweight and obese and 3.0% were thinner. The majority of the children (54.5%) presented food self- control. The caregivers showed good knowledge in the scope of food, with an average score of 82.0%. There was a positive significant correlation between the educator and the first choice of the children. Regarding the children’s choices secondary to the nutritionist’s intervention, no significant differences were found. However, although not statistically significant it is clinically relevant, because 25 of the 66 participating children improved their choices. Conclusions: In the preschool stage, the nutritionist intervention can be highly beneficial. Educating for healthy habits and lifestyles, increasing awareness for food good practices and strengthening children self-control might contribute positively to the struggle against childhood obesity.info:eu-repo/semantics/publishedVersio

High-fat diet-induced obesity rat model: a comparison between wistar and sprague-dawley rat

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Role of protein kinase R in the killing of Leishmania major by macrophages in response to neutrophil elastase and TLR4 via TNF and IFN

In cutaneous leishmaniasis, Leishmania amazonensis activates macrophage double-stranded, RNA-activated protein kinase R (PKR) to promote parasite growth. In our study, Leishmania major grew normally in RAW cells, RAW-expressing dominant-negative PKR (PKR-DN) cells, and macrophages of PKR-knockout mice, revealing that PKR is dispensable for L. major growth in macrophages. PKR activation in infected macrophages with poly I:C resulted in parasite death. Fifty percent of L. major-knockout lines for the ecotin-like serine peptidase inhibitor (ISP2; Δisp2/isp3), an inhibitor of neutrophil elastase (NE), died in RAW cells or macrophages from 129Sv mice, as a result of PKR activation. Inhibition of PKR or NE or neutralization of Toll-like receptor 4 or 2(TLR4 or TLR2) prevented the death of Δisp2/isp3. Δisp2/isp3 grew normally in RAW-PKR-DN cells or macrophages from 129Sv pkr−/−, tlr2−/−, trif−/−, and myd88−/− mice, associating NE activity, PKR, and TLR responses with parasite death. Δisp2/isp3 increased the expression of mRNA for TNF-α by 2-fold and of interferon β (IFNβ) in a PKR-dependent manner. Antibodies to TNF-α reversed the 95% killing by Δisp2/isp3, whereas they grew normally in macrophages from IFN receptor–knockout mice. We propose that ISP2 prevents the activation of PKR via an NE-TLR4-TLR2 axis to control innate responses that contribute to the killing of L. major.—Faria, M. S., Calegari-Silva, T. C., de Carvalho Vivarini, A., Mottram, J. C., Lopes, U. G., Lima, A. P. C. A. Role of protein kinase R in the killing of Leishmania major by macrophages in response to neutrophil elastase and TLR4 via TNFα and IFNβ

Osteogenic induction of hBMSCs by electrospun scaffolds with dexamethasone release functionality

Electrospun structures were proposed as scaffolds owing to their morphological and structural similarities with the extracellular matrix found in many native tissues. These !brous structures were also proposed as drug release systems by exploiting the direct dependence of the release rate of a drug on the surface area. An osteogenic differentiation factor, dexamethasone (DEX), was incorporated into electrospun polycaprolactone (PCL) nano!bers at different concentrations (5, 10, 15 and 20 wt.% polymer), in a single-step process. The DEX incorporated into the polymeric carrier is in amorphous state, as determined by DSC, and does not in"uence the typical nano!bers morphology. In vitro drug release studies demonstrated that the dexamethasone release was sustained over a period of 15 days. The bioactivity of the released dexamethasone was assessed by cultivating human bone marrow mesenchymal stem cells (hBMSCs) on 15 wt.% DEX-loaded PCL NFMs, under dexamethasone-absent osteogenic differentiation medium formulation. An increased concentration of alkaline phosphatase and deposition of a mineralized matrix was observed. Phenotypic and genotypic expression of osteoblastic-speci!c markers corroborates the osteogenic activity of the loaded growth/differentiation factor. Overall data suggests that the electrospun biodegradable nano!bers can be used as carriers for the sustained release of growth/differentiation factors relevant for bone tissue engineering strategies.This work was partially supported by the European Network of Excellence EXPERTISSUES (NMP3-CT-2004-500283). The Portuguese Foundation for Science and Technology was acknowledged for the PhD grant of A. Martins (SFRH/BD/24382/2005)

Prediction of friction degradation in highways with linear mixed models

The development of a linear mixed model to describe the degradation of friction on flexible road pavements to be included in pavement management systems is the aim of this study. It also aims at showing that, at the network level, factors such as temperature, rainfall, hypsometry, type of layer, and geometric alignment features may influence the degradation of friction throughout time. A dataset from six districts of Portugal with 7204 sections was made available by the Ascendi Concession highway network. Linear mixed models with random effects in the intercept were developed for the two-level and three-level datasets involving time, section and district. While the three-level models are region-specific, the two-level models offer the possibility to be adopted to other areas. For both levels, two approaches were made: One integrating into the model only the variables inherent to traffic and climate conditions and the other including also the factors intrinsic to the highway characteristics. The prediction accuracy of the model was improved when the variables hypsometry, geometrical features, and type of layer were considered. Therefore, accurate predictions for friction evolution throughout time are available to assist the network manager to optimize the overall level of road safety.This research was funded by FCT—Fundação para a Ciência e Tecnologia (Foundation for Science and Technology), Grants No. UIDB/04029/2020 and UIDB/00319/2020

Effect of zeolite nanomaterials in methanogenic communities

Recently, the application of zeolite structures in methanogenic communities has attracted significant attention, since they may enhance the anaerobic digestion process, by affecting specifically the methanogenic activity of the sludges1. Zeolites are solid inorganic crystalline materials comprised of silicon, aluminum and oxygen in the three-dimensional structure. The building blocks become arranged in a periodic way to form channels and cages on a nano- and subnanometer scale of strictly regular dimensions, named micropores. The presence of the aluminum in the zeolite framework create a negative charge in the lattice, which can be balanced by the exchangeable cations, as sodium or metal ions.2 In this study, commercial zeolite structures (ZSM5, USY, NaX and NaY) with different particle sizes and different exchangeable cations (Co, Cu, Zn, Fe) were used in order to investigate their effect towards the specific methanogenic activity, both acetoclastic and hydrogenotrophic, of anaerobic sludge. In the acetoclastic methanogenic activity, NaY modified with Cobalt (CoY) decreased the activity in comparison with the control (without zeolite). The remaining zeolites (ZSM5, USY, NaX and NaY), even when modified with metal ions (Zn, Fe, Cu), seems to have no effect on this methanogenic pathway. On the other hand, the hydrogenotrophic methanogenesis was improved by the presence of NaY (109 %), which did not happen in the presence of ZSM5 and USY zeolites. Additionally, the effect of different zeolite concentration was accessed. Overall, the increase of zeolite concentration from 1 g/L to 5 g/L resulted in a higher inhibition towards the methanogenic activity. In addition, the application of these nanomaterials can be evaluated in pure cultures of methanogens, in order to understand and fine-tune the best zeolite nanomaterial concentration that may improve the specific methanogenic activity.We thank the Fundação para a Ciência e Tecnologia (FCT) for financial support through Centre of Chemistry (UID/QUI/00686/2013 and UID/QUI/0686/2016) and BioTecNorte (operation NORTE-01-0145-FEDER-000004), and through Centre of Biological -engineering (UIDB/04469/2020 unit). Cátia S. N. Braga holds a grant SFRH/BD/132003/2017 funded by FCT and European Union (EU), through the Portuguese State Budget and the European Social Fund under the scope of Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio

Comparative study of the microbial diversity of bulk paddy soil of two rice fields subjected to organic and conventional farming

Two adjacent paddies of an experimental rice field, subjected to organic and conventional farming, were characterized aiming the comparative assessment of microbiological variations occurring in the bulk paddy soil over the rice cycle. This study comprehended the simultaneous characterization of general physicochemical soil properties [total carbon and nitrogen, pH (H2O and KCl), C:N ratio and water content], biochemical properties [enzymatic activities and Community Level Physiological Profiles (CLPP)], the estimation of cultivable organisms (enumeration of fast growing heterotrophic bacteria, actinomycetes and fungi) and the assessment of bacterial diversity using a culture-independent method (PCR-DGGE fingerprinting). The linkage of the parameters measured was analysed by canonical correspondence analysis (CCA). CCA ordination plots of the CLPP showed a similar pattern of microbial functional activity in both agronomic management systems, except in June. Enzymatic activity, water content and fungi counts were the main factors affecting the observed CLPP time variation. Such a variation was not expressed by the Shannon and evenness indices, which did not evidence significant differences in the bacterial and functional diversity between or within farming type over the analysed period. The cluster and CCA analyses of the DGGE profiles allowed the distinction of the bacterial communities of both paddies, with temporal variations being observed in the organically managed field but not in the conventional paddy. Enzymatic activity, pH and molinate content were the factors which most contributed to the observed variations. Altogether these results underline the functional redundancy of the rice paddy soil and evidence the temporal variations on the metabolic activity of soil, irrespective of farming type.info:eu-repo/semantics/acceptedVersio