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Background: Type 1 diabetes (T1D) is a chronic autoimmune disease affecting people globally. Usually developed during childhood, T1D is characterized by the destruction of pancreatic β-cells due to immune cell attack and the establishment of an inflammatory process. Objective: The study aimed to investigate the effects of vitamin D through its nuclear receptor and the ω-3 polyunsaturated fatty acids (PUFAs) through their lipid derivatives in T1D modulation. Both components exert anti-inflammatory activity and act directly on cells of the immune system, attenuating the destruction of insulin-producing cells. Furthermore, they lead to a better glycemic level, reducing the need for insulin and a normal immune state, such as C-peptide maintenance. Method: Presently, our review highlights the significant studies that evaluated the supplementation of vitamin D and ω-3 PUFAs in humans and animal models in the modulation of T1D. Conclusion: The data collected suggests that supplementation can provide potential benefits, mainly when done early in the diagnosis, since it reduces the need for insulin and the risk of complications generated by the disease.

Type 1 diabetes mellitus (T1D) is a chronic autoimmune disease characterized by insulin-producing pancreatic β-cell destruction and hyperglycemia. While monocytes and NOD-like receptor family-pyrin domain containing 3 (NLRP3) are associated with T1D onset and development, the specific receptors and factors involved in NLRP3 inflammasome activation remain unknown. Herein, we evaluated the inflammatory state of resident peritoneal macrophages (PMs) from genetically modified non-obese diabetic (NOD), NLRP3-KO, wild-type (WT) mice and in peripheral blood mononuclear cells (PBMCs) from human T1D patients. We also assessed the effect of docosahexaenoic acid (DHA) on the inflammatory status. Macrophages from STZ-induced T1D mice exhibited increased inflammatory cytokine/chemokine levels, nitric oxide (NO) secretion, NLRP3 and iNOS protein levels, and augmented glycolytic activity compared to control animals. In PMs from NOD and STZ-induced T1D mice, DHA reduced NO production and attenuated the inflammatory state. Furthermore, iNOS and IL-1β protein expression levels and NO production were lower in the PMs from diabetic NLRP3-KO mice than from WT mice. We also observed increased IL-1β secretion in PBMCs from T1D patients and immortalized murine macrophages treated with advanced glycation end products and palmitic acid. The present study demonstrated that the resident PMs are in a proinflammatory state characterized by increased NLRP3/iNOS pathway-mediated NO production, up-regulated proinflammatory cytokine/chemokine receptor expression and altered glycolytic activity. Notably, ex vivo treatment with DHA reverted the diabetes-induced changes and attenuated the macrophage inflammatory state. It is plausible that DHA supplementation could be employed as adjuvant therapy for treating individuals with T1D.

The immune system can recognize microbes and sterile tissue damage. Among the damage-associated molecular patterns (DAMPs), uric acid is considered a major component which can trigger inflammation. It represents a breakpoint in the evolutionary history of humans as our ancestors lost the uricase gene, the enzyme responsible for its cleavage. High soluble uric acid (sUA) concentration is able to increase IL-1β in murine, but not human macrophages. We observed that sUA increased the mRNA expression of Naip1 in murine macrophages, and, therefore, we hypothesized that the recognition of sUA can be made by a Naip1-Nlrp3 inflammasome platform. Additionally, we used genome-wide transcriptome analysis, functional analyses and structural modeling predictions and observed that virus-transduction of murine Naip1 into human macrophages induced IL-1β after sUA stimulus, besides leading to fatty acid production and an inflammation-related response. Moreover, pharmacologic inhibition and genetic loss of Nlrp3 led to decreased IL-1β production upon sUA stimulus. Surface plasmon resonance and quartz crystal microbalance showed that sUA is able to interact with Naip1. Naip could be a lost receptor for sUA in the evolutionary process and a better understanding of the immune modulatory function of sUA could lead to design rational novel anti-hyperuricemic therapies.

Leukocytes are potent regulators of adipose tissue biology and whole-body metabolic homeostasis. In lean, non-obese conditions (insulin-sensitive), adipose tissue has innate and adaptive immune cells, including eosinophils, regulatory T cells, invariant NK cells, and M2 macrophages. A vast expansion in adipose tissue occurs in obesity, and this is associated with a marked alteration in the tissue leukocyte profile. There is a marked increase in B cells, CD8+ T cells, NK cells, neutrophils, and M1 macrophages. This condition induces a state of low-grade, chronic inflammation in the adipose tissue, which disrupts whole-body metabolism. Macrophages were the first leukocyte to be discovered in adipose tissue. Due to their proximity to nearby adipocytes, the macrophages are exposed to high levels of fatty acids and other lipids reported in obesity. Lipid uptake by tissue-resident macrophages is essential for their biological actions. Specifically, lipid uptake and metabolism, particularly of long-chain saturated fatty acids, activate inflammatory signaling pathways, potentiating adipose tissue inflammation, and metabolic dysfunction. Obesity exhibits increased fatty acid levels within the adipose tissue microenvironment. The increased lipid accumulation in the resident macrophages reflects the fatty acid composition of the adipocytes. The dietary fatty acid determines the fatty acid composition of the adipose tissue. Macrophages then accumulate fatty acids indirectly provided by the diet. The composition varies with the acyl chain length, e.g., short-, medium-, or long-chain, and saturated fatty acids. These fatty acids have wide-ranging effects on macrophages. We described herein in detail the impact of the different dietary fatty acids on macrophage functions. Shortly, long-chain saturated fatty acids are pro-inflammatory, whereas medium-chain fatty acids are relatively benign. Long-chain unsaturated fatty acids often antagonize the pro-inflammatory effects of long-chain saturated fatty acids.

Sitagliptin is a dipeptidyl peptidase-4 inhibitor (iDPP-4), which has been used for type 2 diabetes treatment. Recently, iDPP-4 has been described as a promising treatment of type 1 diabetes (T1D) but is still necessary to evaluate immune effects of sitagliptin. C57BL/6 mice were induced by multiple low doses of streptozotocin. Diabetes incidence, insulin, glucagon, glucagon-like peptide-1 (GLP-1) serum levels, and inflammatory cytokine levels were quantified in pancreas homogenate after 30 and 90 days of treatment. In addition, frequencies of inflammatory and regulatory T cell subsets were determined in the spleen and in the pancreatic lymph nodes. iDPP-4 decreased blood glucose level while increased GLP-1 and insulin levels. After long-term treatment, treated diabetic mice presented decreased frequency of CD4+CD26+ T cells and increased percentage of CD4+CD25hiFoxp3+ T cells in the spleen. Besides, pancreatic lymph nodes from diabetic mice treated with iDPP-4 presented lower percentage of CD11b+ cells and decreased levels of inflammatory cytokines in the pancreas. Treatment of type 1 diabetic mice with iDPP-4 improved metabolic control, decreased inflammatory profile in the pancreatic microenvironment, and increased systemic regulatory T cell frequency. Therefore, we suggest the long-term use of sitagliptin as a feasible and effective therapy for T1D.

O diabetes mellitus tipo I (DMI) é uma doença crônica autoimune caracterizada por hiperglicemia devido à destruição das células beta pancreáticas produtoras de insulina. Ao final de 30 dias da indução do diabetes por estreptozotocina, os macrófagos peritoneais residentes dos animais diabéticos apresentaram aumento de RNAm de citocinas e quimiocinas inflamatórias, secreção de óxido nítrico, expressão de NLRP3, iNOS e PARP1 e da atividade da via glicolítica. Perfil pró-inflamatório também foi observado em macrófagos peritoneais de animais NOD (non-obese diabetic). Camundongos diabéticos deficientes em NLRP3 (NLRP3 KO) apresentaram diminuição na expressão de iNOS, PARP1 e na produção de NO em relação aos macrófagos dos animais diabéticos selvagens. O estado diabético tipo I influenciou o perfil dos macrófagos peritoneais residentes, causando aumento na produção de NO, via NLRP3-PARP1-iNOS, expressão de citocinas pró-inflamatórias, receptores de quimiocinas e da atividade glicolítica. O tratamento com DHA (ômega-3) ex-vivo reverteu este perfil e atenuou o quadro pró-inflamatório por diminuição da produção de NO e da expressão de citocinas pró-inflamatórias. Type I diabetes mellitus (DMI) is a chronic autoimmune disease characterized by hyperglycemia due to the destruction of insulin-producing pancreatic beta cells. At the end of 30 days after type I diabetes induced by streptozotocin, macrophages from diabetic animals had increased expressions of inflammatory cytokines and chemokines, secretion of nitric oxide, expression of NLRP3, iNOS and PARP1, and glycolytic activity compared to the cells from control animals. Proinflammatory features was also observed in peritoneal macrophages of NOD (non-obese diabetic) animals. Macrophages from NLRP3 deficient diabetic mice (NLRP3 KO) had decreased expression of iNOS, PARP1 and of NO production when compared to cells from wild type animals. The type I diabetic state led to a proinflammatory feature in resident peritoneal macrophages by increasing NO production, via the NLRP3-PARP1-iNOS pathway, expressions of proinflammatory cytokines, chemokine receptors and glycolytic activity. In contrast, ex-vivo treatment with DHA (omega-3) reversed this profile and attenuated the proinflammatory state by reducing NO production and expression of proinflammatory cytokines.

Assembly of a relatively large protein aggregate or "speck" formed by the adaptor protein ASC is a common downstream step in the activation of most inflammasomes. This unique feature of ASC allows its visualization by several imaging techniques and constitutes a reliable and feasible readout for inflammasome activation in cells and tissues. We have previously described step-by-step protocols to generate immortalized cell lines stably expressing ASC fused to a fluorescent protein for measuring inflammasome activation by confocal microscopy, and immunofluorescence of endogenous ASC in primary cells. Here, we present two more methods to detect ASC speck formation: (1) Assessment of ASC speck formation by flow cytometry; and (2) Chemical cross-linking of ASC followed by immunoblotting. These methods allow for the discrimination of inflammasome-activated versus non-activated cells, the identification of lineage-specific inflammasome activation in complex cell mixtures, and sorting of inflammasome-activated cells for further analysis.

Obesogenic diets increase body weight and cause insulin resistance (IR), however, the association of these changes with the main macronutrient in the diet remains to be elucidated. Male C57BL/6 mice were fed with: control (CD), CD and sweetened condensed milk (HS), high-fat (HF), and HF and condensed milk (HSHF). After 2 months, increased body weight, glucose intolerance, adipocyte size and cholesterol levels were observed. As compared with CD, HS ingested the same amount of calories whereas HF and HSHF ingested less. HS had increased plasma AST activity and liver type I collagen. HF caused mild liver steatosis and hepatocellular damage. HF and HSHF increased LDL-cholesterol, hepatocyte and adipocyte hypertrophy, TNF-α by macrophages and decreased lipogenesis and adiponectin in adipose tissue (AT). HSHF exacerbated these effects, increasing IR, lipolysis, mRNA expression of F4/80 and leptin in AT, Tlr-4 in soleus muscle and IL-6, IL-1β, VCAM-1, and ICAM-1 protein in AT. The three obesogenic diets induced obesity and metabolic dysfunction. HS was more proinflammatory than the HF and induced hepatic fibrosis. The HF was more detrimental in terms of insulin sensitivity, and it caused liver steatosis. The combination HSHF exacerbated the effects of each separately on insulin resistance and AT inflammatory state.

Uric acid is a damage-associated molecular pattern (DAMP), released from ischemic tissues and dying cells which, when crystalized, is able to activate the NLRP3 inflammasome. Soluble uric acid (sUA) is found in high concentrations in the serum of great apes, and even higher in some diseases, before the appearance of crystals. In the present study, we sought to investigate whether uric acid, in the soluble form, could also activate the NLRP3 inflammasome and induce the production of IL-1β. We monitored ROS, mitochondrial area and respiratory parameters from macrophages following sUA stimulus. We observed that sUA is released in a hypoxic environment and is able to induce IL-1β release. This process is followed by production of mitochondrial ROS, ASC speck formation and caspase-1 activation. Nlrp3−/− macrophages presented a protected redox state, increased maximum and reserve oxygen consumption ratio (OCR) and higher VDAC protein levels when compared to WT and Myd88−/− cells. Using a disease model characterized by increased sUA levels, we observed a correlation between sUA, inflammasome activation and fibrosis. These findings suggest sUA activates the NLRP3 inflammasome. We propose that future therapeutic strategies for renal fibrosis should include strategies that block sUA or inhibit its recognition by phagocytes. © The Author(s) 2017. This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/

A balance between proinflammatory (Th17 and Tc17) and anti-inflammatory (regulatory T cells) subsets of T cells is essential to maintain immunological tolerance and prevent the onset of several autoimmune diseases, including type 1 diabetes. However, the kinetics of these subsets and disease severity during the streptozotocin (STZ)-induced diabetes course has not been determined. Thus, susceptible C57BL/6 mice were administrated with multiple low doses of STZ and we evaluated the frequency/absolute number of these T cell subsets in the pancreatic lymph nodes (PLNs) and spleen and Th1, Th17, Treg cytokine production in the pancreatic tissue. At different time points of the disease progression (6, 11, 18 and 25 days after the last STZ administration), the histopathological alterations were also evaluated by H&E and immunohistochemistry staining. During the initial phase of diabetes development (day 6), we noted increased numbers of CD4(+) and CD8(+) T cells in spleen and PLNs. At the same time, the frequencies of Th17 and Tc17 cells in PLNs were also enhanced. In addition, the early augment of interferon gamma (IFN-γ), tumoral necrosis factor (TNF-α), IL-6 and IL-17 levels in pancreatic tissue correlated with pancreatic islet inflammation and mild β-cell damage. Notably, the absolute number of Treg cells increased in PLNs during over time when compared to control group. Interestingly, increased IL-10 levels were associated with control of the inflammatory process during the late phase of the type 1 diabetes (day 25). In agreement, mice lacking the expression of IL-17 receptor (Il17r) showed impairment in STZ-induced diabetes progression, reduced peri-insulitis and beta cells preservation when compared with wild-type mice. Our findings suggest that dynamic changes of pathogenic Th17/Tc17 and regulatory T cell subsets numbers is associated with early strong inflammation in the pancreatic islets followed by late regulatory profile during the experimental STZ-induced diabetes course.

Made available in DSpace on 2015-03-18T15:55:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-01-01Bitstream added on 2015-03-18T16:28:36Z : No. of bitstreams: 1 WOS000344673400001.epub: 1369846 bytes, checksum: bc6efb2183924a71e7fb2e30828cb77c (MD5)Bitstream added on 2015-03-18T16:28:36Z : No. of bitstreams: 2 WOS000344673400001.epub: 1369846 bytes, checksum: bc6efb2183924a71e7fb2e30828cb77c (MD5) WOS000344673400001.pdf: 2000918 bytes, checksum: 799fc4c459de9af835594951c96f9c0d (MD5) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Excess of saturated fatty acids in the diet has been associated with obesity, leading to systemic disruption of insulin signaling, glucose intolerance, and inflammation. Macadamia oil administration has been shown to improve lipid profile in humans. We evaluated the effect of macadamia oil supplementation on insulin sensitivity, inflammation, lipid profile, and adipocyte size in high-fat diet (HF) induced obesity in mice. C57BL/6 male mice (8 weeks) were divided into four groups: (a) control diet (CD), (b) HF, (c) CD supplemented with macadamia oil by gavage at 2g/Kg of body weight, three times per week, for 12 weeks (CD + MO), and (d) HF diet supplemented with macadamia oil (HF + MO). CD and HF mice were supplemented with water. HF mice showed hypercholesterolemia and decreased insulin sensitivity as also previously shown. HF induced inflammation in adipose tissue and peritoneal macrophages, as well as adipocyte hypertrophy. Macadamia oil supplementation attenuated hypertrophy of adipocytes and inflammation in the adipose tissue and macrophages. Univ Sao Paulo, Dept Biol Celular & Desenvolvimento, BR-05508000 Sao Paulo, Brazil Univ Estadual Paulista, UNESP, Dept Educ Fis, Programa Posgrad Ciencia Motricidad, BR-13506900 Rio Claro, SP, Brazil Univ Sao Paulo, Inst Ciencias Biomed, Dept Fisiol & Biofis, BR-05508000 Sao Paulo, Brazil Univ Sao Judas Tadeu, Dept Ciencias Biol, Lab Movimento Humano, BR-05503001 Sao Paulo, Brazil Univ Fed Sao Paulo, Dept Fisiol, Disciplina Fisiol Nutr, BR-04023901 Sao Paulo, Brazil Univ Sao Paulo, Inst Biociencias, Dept Fisiol Geral, BR-05508090 Sao Paulo, Brazil Univ Cruzeiro Sul, Inst Ciencias Atividade Fis & Esporte, Programa Posgrad Ciencia Movimento Humano, BR-01506000 Sao Paulo, Brazil Univ Estadual Paulista, UNESP, Dept Educ Fis, Programa Posgrad Ciencia Motricidad, BR-13506900 Rio Claro, SP, Brazil

O diabetes mellitus do tipo 1 (DM1) é uma doença autoimune caracterizada pela destruição seletiva de células pancreáticas produtoras de insulina. Existem diversas formas de tratamento do DM1, tais como administração de insulina, imunossupressores, transplantes de pâncreas ou de ilhotas pancreáticas, porém todos se mostram ineficientes em algum aspecto. Recentemente, uma nova classe de medicamentos, os inibidores da enzima dipeptidil peptidase 4 (iDPP-4), demonstrou eficiência terapêutica e segurança no tratamento de pacientes com diabetes mellitus do tipo 2 devido ao aumento do hormônio peptídeo-1 semelhante ao glucagon (GLP-1, do inglês glucagon-like peptide-1). Além disso, o uso de inibidores de DPP-4 em modelos experimentais de DM1 demonstrou proteção das células pancreáticas contra apoptose, estimulação de neogênese de ilhotas pancreáticas e melhora do controle homeostático da glicose. Esse presente projeto teve como objetivo avaliar o perfil imunológico e endocrinológico da administração do inibidor de DPP-4 (MK0431) em DM1 experimental quimicamente induzido por estreptozotocina em camundongos C57Bl/6. Os animais diabéticos foram tratados com ração controle ou ração contendo inibidor de DPP-4 (4g MK0431/Kg de ração) ad libitum durante 30 e 90 dias. Durante o tratamento os animais tiveram glicemia, peso e teste de tolerância oral à glicose avaliados. Ao final do tratamento, os animais foram eutanasiados e o sangue, baço, timo, linfonodos pancreáticos e pâncreas foram coletados. Após 30 dias de tratamento com inibidor, foi observado um aumento do hormônio GLP-1 no soro, além de um padrão imunológico favorável. Dentre os mecanismos imunológicos, foi possível observar um aumento de células T reguladoras (CD4+CD25+Foxp3+) no baço e uma diminuição da citocina IFN- no homogenato pancreático. Após 90 dias de tratamento com inibidor, também foi detectado um aumento de insulina e GLP-1 séricos e uma diminuição nos níveis glicêmicos dos animais tratados. Observou-se uma redução no padrão inflamatório no microambiente pancreático, caracterizado pela diminuição das citocinas TNF- e IFN- no homogenato pancreático e por uma redução da freqüência de macrófagos CD11b+ nos linfonodos pancreáticos. Os resultados obtidos neste projeto contribuíram para validar a eficácia terapêutica da administração de inibidor de DPP-4 no tratamento do DM1 experimental, bem como os mecanismos imunológicos e endocrinológicos envolvidos. Sem a ocorrência de efeitos tóxicos relevantes, o uso de inibidores de DPP-4 pode se tornar uma alternativa terapêutica para o tratamento do DM1 em humanos, que constitui uma doença crônica associada à baixa qualidade de vida em longo prazo e necessidade de tratamento de alto custo. Davanso, M.R. Immunoendocrinological analyses after administration of dipeptidyl-peptidase-4 inhibitor on experimental type 1 diabetes. 2012. 105p. Thesis (Masters Degree) School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, 2012. Type 1 Diabetes Mellitus (DM1) is an autoimmune disease characterized by the selective destruction of the insulin-producing pancreatic cells. Several forms of treatment for DM1 are current known such as insulin administration, immunosuppressors, pancreas or pancreatic islets transplantation, however, they all are inefficient in some aspect. Recently, a new class of drugs, the dipeptidyl-peptidase-4 inhibitors (iDPP-4) showed therapeutic efficacy and safety in the treatment with type 2 diabetes mellitus patients due to an increase in the glucagon-like peptide-1 (GLP-1). In addition, the use of DPP-4 inhibitors in experimental models of DM1 has demonstrated a protection of pancreatic cells against apoptosis, stimulation of pancreatic islets neogenesis and improvement in the glucose homeostatic control. This project evaluated the immunological and endocrinological profile of the DPP-4 (MK0431) inhibitor administration in experimental chemically induced DM1 by streptozotocin in C57BI/6 mice. The diabetic animals were treated with either a normal chow diet or diet containing DPP-4 inhibitor (4g MK0431/Kg of diet) ad libitum during 30 and 90 days. During the treatment the animals were evaluated regarding glycemia, weight, and oral glucose tolerance test. At the end of the treatment, the animals were killed and the blood, spleen, thymus, pancreatic lymph nodes and pancreas were collected. After 30 days of treatment with inhibitor, it was observed an increase in the hormone GLP-1 in the serum, besides a favorable immunological pattern. Among the immunologic mechanisms, it was possible to observe an increase in the regulator T cells (CD4+CD25+Foxp3+) of the spleen and a decrease in the cytokine IFN- in the pancreatic homogenate. After 90 days of treatment with inhibitor, it was also noticed an increase in the insulin and serum GLP-1 levels as well as a decrease in the glycemic levels in the treated animals. It was observed a reduction in the inflammatory pattern in the pancreatic microenvironment characterized by a decrease in the cytokines TNF- and IFN- in the pancreatic homogenate and by a reduction in the frequency of CD11b+ macrophages in the pancreatic lymph nodes. The results obtained in this project contributed to validate the therapeutic efficacy of the DPP-4 inhibitor administration in the treatment of experimental DM1, as well as the immunological and endocrinological mechanisms involved. Without the occurrence of relevant toxic effects, the use of DPP-4 inhibitors may become a therapeutic alternative for the treatment of DM1 in humans, which constitutes a chronic disease associated to low life quality and need for high cost treatment.