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1.
Immunobiology ; : 151879, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31812346

RESUMO

Diabetes causes dysregulation in signal transduction in immune cells leading to an impaired response to pathogens. Herein, we investigated the impact of type 1 diabetes (T1D) in bone marrow-derived macrophages (BMDM), using male non-diabetic and diabetic C57BL/6 mice (alloxan 60 mg/kg, i.v., CEUA/FCF/USP - 467). Diabetic BMDM expressed impaired phosphoinositide 3-kinase (PI3K), being lower p-PI3K p55 levels and higher levels of PI3K p110 alpha, whereas protein kinase B (PKB/Akt) (Ser-473 and Thr-308), extracellular signal-regulated kinases (ERK 1/2), and stress-activated protein kinase (SAPK/JNK) were enhanced compared to non-diabetic BMDM. Further evaluation of the responsiveness to lipopolysaccharide (LPS; 0.1 and 1 ug/mL), diabetic BMDM and peritoneal macrophage secreted dysregulated levels of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-10 levels. In 24 h, diabetic BMDM stimulated by LPS presented lower metabolic activity, with no differences in cell surveillance. Therefore, LPS re-stimulation (0.1 ug/mL) in diabetic BMDM resulted in higher secretion of TNF-α compared to non-diabetic BMDM. However, diabetic peritoneal macrophages secreted similar IL-6 levels in the first and additional 24 h of LPS stimulation. In general, our results demonstrated that diabetes exerts an impact in both BMDM and peritoneal macrophages ability to secrete cytokine under LPS stimulation.

2.
Sci Rep ; 9(1): 11447, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31391499

RESUMO

Macrophages may be a crucial aspect of diabetic complications associated with the inflammatory response. In this study, we examined how hyperglycaemia, a common aspect of diabetes, modulates bone marrow-derived macrophages (BMDMs) under an inflammatory stimulus. To perform this study, BMDMs from non-diabetic and diabetic (60 mg/kg alloxan, i.v.) male C57BL/6 mice (CEUA/FCF/USP-488) were cultured under normal (5.5 mM) and high glucose (HG, 25 or 40 mM) conditions and stimulated or not stimulated with lipopolysaccharide (LPS, 100 ng/mL). Compared to the BMDMs from the normoglycaemic mice, the LPS-stimulated BMDMs from the diabetic mice presented reduced TLR4 expression on the cell surface, lower phagocytic capacity, and reduced secretion of NO and lactate but greater oxygen consumption and greater phosphorylation of p46 SAPK/JNK, p42 ERK MAPK, pAKT and pPKC-δ. When the BMDMs from the non-diabetic mice were cultured under high-glucose conditions and stimulated with LPS, TLR4 expression was reduced on the cell surface and NO and H2O2 levels were reduced. In contrast, the diabetic BMDMs cultured under high glucose conditions presented increased levels of lactate and reduced phosphorylation of AKT, PKC-δ and p46 SAPK/JNK but enhanced phosphorylation of the p46 subunit of SAPK/JNK after LPS stimulation. High glucose levels appear to modify macrophage behaviour, affecting different aspects of diabetic and healthy BMDMs under the same LPS stimulus. Thus, hyperglycaemia leaves a glucose legacy, altering the basal steady state of macrophages.

3.
São Paulo; s.n; s.n; 2019. 153 p. graf, ilus.
Tese em Português | LILACS | ID: biblio-996744

RESUMO

O diabetes mellitus é um grupo heterogêneo de distúrbios metabólicos caracterizado pela hiperglicemia. Indivíduos diabéticos possuem maior susceptibilidade a infecções comparado a indivíduos sadios e a hiperglicemia é um dos principais fatores que contribuem para isso, em parte, por alterar a resposta imune. Sendo assim, os macrófagos, como células essenciais para a resposta inflamatória, podem apresentar importante papel na resposta imune alterada de indivíduos diabéticos. Neste estudo, investigamos como a hiperglicemia modula os macrófagos derivados da medula óssea (BMDMs) sob um estímulo inflamatório. Para realizar este estudo, os BMDMs de camundongos C57BL/6 machos não diabéticos e diabéticos (60 mg/kg de aloxana, iv) (CEUA / FCF / USP-488) foram cultivados sob condições normais de glicose (5,5 mM) e alta concentração de glicose (25 mM ou 40 mM) e estimuladas ou não com lipopolissacarídeo (LPS, 100 ng/mL). Em comparação com os BMDMs dos camundongos não diabéticos, os BMDMs dos camundongos diabéticos estimulados com LPS apresentaram menor expressão de CD38 no tempo basal e após 24 horas, além de menor expressão de receptor do tipo Toll (TLR)-4 na superfície celular, menor capacidade fagocítica e redução na secreção de óxido nítrico, lactato, fator de necrose tumoral- e interleucina (IL)-10, porém apresentaram maior expressão de CD80, CD86 e MHC-II, maior consumo de oxigênio e maior fosforilação em quinase ativada por estresse/quinase Jun-amino-terminal (SAPK/JNK) subunidade p46 e em quinase regulada por sinal extracelular (ERK) subunidade p42, proteína quinase B (AKT) e proteína quinase C (PKC)-δ assim como maior secreção de IL-6. Quando os BMDMs dos camundongos não diabéticos foram cultivados sob condições de alta concentração de glicose in vitro e estimulados com LPS, a expressão de TLR4 e os níveis de óxido nítrico e peróxido de hidrogênio foram reduzidos. Por outro lado, os BMDMs diabéticos que também foram cultivados em alta concentração de glicose in vitro apresentaram níveis aumentados de lactato e fosforilação reduzida em AKT e PKC-δ, porém apresentaram fosforilação aumentada em p46 SAPK/JNK. A alta concentração de glicose parece modificar o comportamento dos macrófagos, afetando diferentes aspectos dos BMDMs diabéticos e não diabéticos sob estímulo de LPS, assim a hiperglicemia deixa um legado de glicose, induzindo uma memória glicêmica, alterando o estado basal dos macrófagos, modificando a via de sinalização do TLR4 contribuindo para a susceptibilidade de indivíduos diabéticos a infecções


Diabetes mellitus is a heterogeneous group of metabolic disorders characterized by hyperglycemia. Diabetic individuals are more susceptible to infections compared to healthy subjects, and hyperglycemia is one of the major contributing factors, partly because they alter the immune response. Thus, macrophages, as essential cells for the inflammatory response, may play an important role in the altered immune response of diabetic individuals. In this study, we investigated how hyperglycemia modulates bone marrow derived macrophages (BMDMs) under an inflammatory stimulus. To perform this study, BMDMs from non-diabetic male and diabetic C57BL/6 mice (60 mg / kg aloxane, iv) (CEUA / FCF / USP-488) were cultured under normal glucose conditions (5.5 mM) and high glucose concentration (25 mM or 40 mM) and stimulated or not with lipopolysaccharide (LPS, 100 ng / ml). Compared to non-diabetic mice BMDMs, the BMDMs of LPS-stimulated diabetic mice showed lower expression of CD38 at baseline and after 24 hours, as well as lower Toll-like receptor (TLR)-4 on the cell surface, lower secretion of lactate, tumor necrosis factor-, and interleukin (IL)-10, but showed higher expression of CD80, CD86 and MHC-II, higher oxygen consumption and greater phosphorylation in stress-activated kinase/Jun-amino-terminal kinase (SAPK / JNK) p46 subunit and in extracellular signal regulated kinase (ERK) p42 subunit, protein kinase B (AKT) and protein kinase C (PKC)-δ as well as higher secretion of IL-6. When the BMDMs of nondiabetic mice were cultured under conditions of in vitro high glucose concentration and stimulated with LPS, the levels of TLR4 expression, nitric oxide and hydrogen peroxide were reduced. On the other hand, diabetic BMDMs that were also cultured in high glucose concentration of glucose in vitro showed increased levels of lactate and reduced phosphorylation in AKT and PKC-δ, but showed increased phosphorylation in p46 SAPK/JNK. A high glucose concentration seems to modify the behavior of macrophages, affecting different aspects of diabetic and non-diabetic BMDMs under the same LPS stimulus. Hyperglycemia leaves a glucose legacy, inducing a glycemic memory, altering the basal state of macrophages, modifying the TLR4 signaling pathway, and may play a key role in the high susceptibility of diabetic individuals to infections


Assuntos
Animais , Masculino , Camundongos , Hiperglicemia/complicações , Inflamação/complicações , Macrófagos/metabolismo , Lipopolissacarídeos , Diabetes Mellitus/classificação , Glucose
4.
Int J Med Mushrooms ; 18(4): 313-20, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27481297

RESUMO

Ganoderma australe was studied to determine the composition of the cell wall, and polysaccharide fraction SK5 was obtained after freeze-thawing an aqueous 5% potassium hydroxide extraction. The monosaccharide composition of the SK5 fraction revealed by gas chromatography-mass spectrometry showed 81.3% glucose, and analyses by 13C nuclear magnetic resonance spectroscopy confirmed a ß-glucan with glycosidic links of the (1→3)-ß type and most likely 4-O substituted. In addition, the biological effect of the ß-glucan from G. australe was evaluated via in vitro cell cultures of peritoneal macrophages isolated from Swiss mice. Biological assays were assessed for toxicity and cell activation, interleukin-6 cytokine concentrations, and the ability to stimulate phagocytic activity. There was an increase in interleukin-6 by approximately 111% with 1.0 µg/mL of polysaccharide, and phagocyte activity was increased in all concentrations examined, obtaining 52.3% with 0.25 µg/mL polysaccharide. The results indicate that a ß-(1→3)-glucan isolated from G. australe can be classified as a biological response modifier.


Assuntos
Ganoderma/química , Fatores Imunológicos/farmacologia , Interleucina-6/metabolismo , Fagocitose/efeitos dos fármacos , Polissacarídeos/farmacologia , beta-Glucanas/farmacologia , Animais , Parede Celular/química , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/imunologia , Camundongos
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