Metformin Inhibits N-Methyl-N-Nitrosourea Induced Gastric Tumorigenesis in db/db Mice

2017 ◽  
Vol 125 (06) ◽  
pp. 392-399 ◽  
Author(s):  
Shan Zhuang ◽  
Yongmei Jian ◽  
Yongning Sun
Keyword(s):  
Gastric Cancer ◽  
Type 2 Diabetes ◽  
Inflammatory Cytokines ◽  
Serum Insulin ◽  
Inhibitory Effect ◽  
Increased Risk ◽  
Pro Inflammatory Cytokines

Abstract Type 2 diabetes can elevate risk of gastric cancer and metformin, an anti-diabetic agent, has an inhibitory effect against gastric cancer cell in vitro. However, the effect of metformin on type 2 diabetes-related gastric tumorigenesis in vivo is still not clear. In the present study, we aim to detect whether metformin can inhibit increased risk of gastric cancer in diabetic db/db mice and which the potential anti-cancer mechanisms of metformin are. 4-week-old mice were divided into 3 groups (2 db/db mice groups and one wild type mice group). All diabetic and non-diabetic mice were treated with N-Methyl-N-Nitrosourea (MNU) for 20 weeks to induce gastric tumorigenesis. At week 21, one db/db mice group were treated with metformin (5 mg/ml) for 10 weeks and the other 2 groups were treated with saline. Blood samples were collected for testing insulin and insulin-like growth factor (IGF)-1. Stomach tissues were collected for histopathological evaluation and mRNAs analysis. Metformin significantly decreased incidence of MNU-induced gastric dysplasia and cancer in diabetic db/db mice. Furthermore, metformin reduced serum insulin as well as IGF-1, and also suppressed expression of insulin receptor, IGF-1, IGF-1 receptor and several pro-inflammatory cytokines mRNAs in stomach of db/db mice, but did not significantly influence IGF-2 and IGF-2 receptor expressions. The results show that metformin can prevent the risk of gastric cancer in type 2 diabetes and the protective mechanisms may involve in an inhibitory effect of metformin on insulin as well as IGF-1 signals and cancer related pro-inflammatory cytokines.

Abstract 424: An IFNg-regulated Macrophage Protein Network Links Type 2 Diabetes to Atherosclerosis

2017 ◽  
Vol 37 (suppl_1) ◽  
Author(s):  
Catherine A Reardon ◽  
Amulya Lingaraju ◽  
Kelly Q Schoenfelt ◽  
Guolin Zhou ◽  
Ning-Chun Liu ◽  
...  
Keyword(s):  
Type 2 Diabetes ◽  
Foam Cell ◽  
Cell Formation ◽  
Foam Cell Formation ◽  
Increased Risk ◽  
Macrophage Dysfunction ◽  
Macrophage Protein

Type 2 diabetics have a higher risk for atherosclerosis, but the mechanisms underlying the increased risk are poorly understood. Macrophages, which are activated in type 2 diabetes (T2D) and have a role in all stages of atherogenesis, are an attractive link. Our hypothesis is that T2D promotes macrophage dysfunction to promote atherosclerosis. To investigate the relationship between T2D and macrophage dysfunction, we used a proteomics approach to identify dysregulated proteins secreted from peritoneal macrophages in a diet induced mouse model of obesity and insulin resistance in the absence of hypercholesterolemia. Twenty-seven T2D responsive proteins were identified that predict defects in many of the critical functions of macrophages in atherosclerosis (e.g. decreased apoE- cholesterol efflux; decreased MFGE8 – efferocytosis, increased MMP12- matrix degradation). The macrophages from lean and obese mice were not lipid loaded, but the obese macrophages accumulated significantly more cholesterol when exposed to high levels of atherogenic lipoproteins in vitro suggesting that dysregulation of the T2D responsive proteins in diabetic mice render macrophages more susceptible to cholesterol loading. Importantly, many of these same protein changes, which were present in atherosclerotic Ldlr-/- mice with T2D, were normalized when these mice were fed non-diabetogenic hypercholesterolemic diets. Thus, foam cell formation in the presence and absence of T2D produces distinct effects on macrophage protein levels, and hence function. Further, we identify IFNγ as a mediator of the T2D responsive protein dysfunction. IFNγ, but not other cytokines, insulin or glucose, promote the T2D responsive protein dysregulation and increased susceptibility to cholesterol accumulation in vitro and the dysregulation is not observed in macrophage foam cells obtained from obese, diabetic IFNγ receptor 1 knockout animals. We also demonstrate that IFNγ can target these proteins in arterial wall macrophages in vivo . These studies suggest that IFNγ is an important mediator of macrophage dysfunction in T2D that may contribute to the enhanced cardiovascular risk in these patients.

scholarly journals Postprandial carbohydrate metabolism in healthy subjects and those with type 2 diabetes fed starches with slow and rapid hydrolysis rates determined in vitro

2003 ◽  
Vol 90 (5) ◽  
pp. 853-864 ◽  
Author(s):  
Chris J. Seal ◽  
Mark E. Daly ◽  
Lois C. Thomas ◽  
Wendy Bal ◽  
Anne M. Birkett ◽  
...  
Keyword(s):  
Type 2 Diabetes ◽  
Carbohydrate Metabolism ◽  
Healthy Subjects ◽  
Serum Insulin ◽  
Postprandial Period ◽  
Rapid Hydrolysis ◽  
Type 2 Diabetic

The objective of the present study was to investigate the effects of starches with differing rates of hydrolysis on exposure to pancreatin in vitro on postprandial carbohydrate metabolism in healthy subjects and in subjects with type 2 diabetes. Two test starches, prepared from uncooked native granular starch products, and naturally enriched with 13C, were consumed in a randomized crossover design by eight healthy and thirteen type 2 diabetic subjects. One starch was characterized in vitro as being rapidly hydrolysed (R, 94% after 180min), and the other was more slowly hydrolysed (S, 51% after 180min). Each subject consumed 50g of each test starch. In addition, the type 2 diabetic subjects consumed 89·7g of the S starch on a separate occasion. Blood samples were taken at 10min intervals for 3h, and at 20min intervals for a further 3h during a 6h postprandial period. Breath 13CO2 enrichment was measured at the same time points, and indirect calorimetry was performed for seven 20min sessions immediately before and during the 6h postprandial period. With the R starch, plasma glucose concentrations and serum insulin concentrations rose faster and the maximum glucose change was approximately 1·8 times that for the S starch, averaged across both subject groups. The areas under the curves for glucose and insulin were, respectively, 1·7 and 1·8 times higher for the R starch compared with the S starch, averaged across both subject groups. The rate of 13CO2 output and the proportion of 13C recovered in breath after consumption of the R starch was similar for both subject groups. The results provide evidence that starches which have different rates of hydrolysis in vitro result in different patterns of glycaemia and insulinaemia in both healthy adults and in diet-controlled type 2 diabetic subjects. Data from the hydrolysis of novel starch products in vitro, therefore, are useful in predicting glycaemic responses in vivo.

Methylmercury-induced pro-inflammatory cytokines activation and its preventive strategy using anti-inflammation N-acetyl-l-cysteine: a mini-review

2020 ◽  
Vol 35 (3) ◽  
pp. 233-238
Author(s):  
Muflihatul Muniroh
Keyword(s):  
Inflammatory Cytokines ◽  
Health Concern ◽  
Brain Cells ◽  
Preventive Strategy ◽  
Hearing Impairments ◽  
Sensory Disturbances ◽  
Anti Inflammation ◽  
Pro Inflammatory Cytokines

AbstractThe exposure of methylmercury (MeHg) has become a public health concern because of its neurotoxic effect. Various neurological symptoms were detected in Minamata disease patients, who got intoxicated by MeHg, including paresthesia, ataxia, gait disturbance, sensory disturbances, tremors, visual, and hearing impairments, indicating that MeHg could pass the blood-brain barrier (BBB) and cause impairment of neurons and other brain cells. Previous studies have reported some expected mechanisms of MeHg-induced neurotoxicity including the neuroinflammation pathway. It was characterized by the up-regulation of numerous pro-inflammatory cytokines expression. Therefore, the use of anti-inflammatories such as N-acetyl-l-cysteine (NAC) may act as a preventive compound to protect the brain from MeHg harmful effects. This mini-review will explain detailed information on MeHg-induced pro-inflammatory cytokines activation as well as possible preventive strategies using anti-inflammation NAC to protect brain cells, particularly in in vivo and in vitro studies.

scholarly journals Experimental Type 2 Diabetes Differently Impacts on the Select Functions of Bone Marrow-Derived Multipotent Stromal Cells

Cells ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 268
Author(s):  
Jonathan Ribot ◽  
Cyprien Denoeud ◽  
Guilhem Frescaline ◽  
Rebecca Landon ◽  
Hervé Petite ◽  
...  
Keyword(s):  
Type 2 Diabetes ◽  
Bone Marrow ◽  
Stromal Cells ◽  
Adipogenic Differentiation ◽  
Therapeutic Modality ◽  
Multipotent Stromal Cells ◽  
Cell Therapies

Bone marrow-derived multipotent stromal cells (BMMSCs) represent an attractive therapeutic modality for cell therapy in type 2 diabetes mellitus (T2DM)-associated complications. T2DM changes the bone marrow environment; however, its effects on BMMSC properties remain unclear. The present study aimed at investigating select functions and differentiation of BMMSCs harvested from the T2DM microenvironment as potential candidates for regenerative medicine. BMMSCs were obtained from Zucker diabetic fatty (ZDF; an obese-T2DM model) rats and their lean littermates (ZL; controls), and cultured under normoglycemic conditions. The BMMSCs derived from ZDF animals were fewer in number, with limited clonogenicity (by 2-fold), adhesion (by 2.9-fold), proliferation (by 50%), migration capability (by 25%), and increased apoptosis rate (by 2.5-fold) compared to their ZL counterparts. Compared to the cultured ZL-BMMSCs, the ZDF-BMMSCs exhibited (i) enhanced adipogenic differentiation (increased number of lipid droplets by 2-fold; upregulation of the Pparg, AdipoQ, and Fabp genes), possibly due to having been primed to undergo such differentiation in vivo prior to cell isolation, and (ii) different angiogenesis-related gene expression in vitro and decreased proangiogenic potential after transplantation in nude mice. These results provided evidence that the T2DM environment impairs BMMSC expansion and select functions pertinent to their efficacy when used in autologous cell therapies.

scholarly journals PAR-4/Ca2+-calpain pathway activation stimulates platelet-derived microparticles in hyperglycemic type 2 diabetes

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Alessandra Giannella ◽  
Giulio Ceolotto ◽  
Claudia Maria Radu ◽  
Arianna Cattelan ◽  
Elisabetta Iori ◽  
...  
Keyword(s):  
Type 2 Diabetes ◽  
Normal Glucose Tolerance ◽  
Calpain Inhibitor ◽  
Pathway Activation ◽  
Normal Glucose ◽  
Circulating Levels ◽  
Dependent Mechanism

Abstract Background Patients with type 2 diabetes (T2DM) have a prothrombotic state that needs to be fully clarified; microparticles (MPs) have emerged as mediators and markers of this condition. Thus, we investigate, in vivo, in T2DM either with good (HbA1c ≤ 7.0%; GGC) or poor (HbA1c > 7.0%; PGC) glycemic control, the circulating levels of MPs, and in vitro, the molecular pathways involved in the release of MPs from platelets (PMP) and tested their pro-inflammatory effects on THP-1 transformed macrophages. Methods In 59 T2DM, and 23 control subjects with normal glucose tolerance (NGT), circulating levels of CD62E+, CD62P+, CD142+, CD45+ MPs were determined by flow cytometry, while plasma levels of ICAM-1, VCAM-1, IL-6 by ELISA. In vitro, PMP release and activation of isolated platelets from GGC and PGC were investigated, along with their effect on IL-6 secretion in THP-1 transformed macrophages. Results We found that MPs CD62P+ (PMP) and CD142+ (tissue factor-bearing MP) were significantly higher in PGC T2DM than GGC T2DM and NGT. Among MPs, PMP were also correlated with HbA1c and IL-6. In vitro, we showed that acute thrombin exposure stimulated a significantly higher PMP release in PGC T2DM than GGC T2DM through a more robust activation of PAR-4 receptor than PAR-1 receptor. Treatment with PAR-4 agonist induced an increased release of PMP in PGC with a Ca2+-calpain dependent mechanism since this effect was blunted by calpain inhibitor. Finally, the uptake of PMP derived from PAR-4 treated PGC platelets into THP-1 transformed macrophages promoted a marked increase of IL-6 release compared to PMP derived from GGC through the activation of the NF-kB pathway. Conclusions These results identify PAR-4 as a mediator of platelet activation, microparticle release, and inflammation, in poorly controlled T2DM.

scholarly journals Elevated circulating follistatin associates with an increased risk of type 2 diabetes

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Chuanyan Wu ◽  
Yan Borné ◽  
Rui Gao ◽  
Maykel López Rodriguez ◽  
William C. Roell ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Type 2 Diabetes ◽  
Adipose Tissue ◽  
Genome Wide Association Study ◽  
Regulatory Protein ◽  
Alcoholic Fatty Liver ◽  
Increased Risk

AbstractThe hepatokine follistatin is elevated in patients with type 2 diabetes (T2D) and promotes hyperglycemia in mice. Here we explore the relationship of plasma follistatin levels with incident T2D and mechanisms involved. Adjusted hazard ratio (HR) per standard deviation (SD) increase in follistatin levels for T2D is 1.24 (CI: 1.04–1.47, p < 0.05) during 19-year follow-up (n = 4060, Sweden); and 1.31 (CI: 1.09–1.58, p < 0.01) during 4-year follow-up (n = 883, Finland). High circulating follistatin associates with adipose tissue insulin resistance and non-alcoholic fatty liver disease (n = 210, Germany). In human adipocytes, follistatin dose-dependently increases free fatty acid release. In genome-wide association study (GWAS), variation in the glucokinase regulatory protein gene (GCKR) associates with plasma follistatin levels (n = 4239, Sweden; n = 885, UK, Italy and Sweden) and GCKR regulates follistatin secretion in hepatocytes in vitro. Our findings suggest that GCKR regulates follistatin secretion and that elevated circulating follistatin associates with an increased risk of T2D by inducing adipose tissue insulin resistance.

scholarly journals Macrophage-Biomimetic Porous Se@SiO2 Nanocomposites For “Dual Model” Immunotherapy Against Inflammatory Osteolysis

2021 ◽  
Author(s):  
Cheng Ding ◽  
Chuang Yang ◽  
Tao Cheng ◽  
Xingyan Wang ◽  
Qiaojie Wang ◽  
...  
Keyword(s):  
Inflammatory Cytokines ◽  
Inflammatory Responses ◽  
Total Joint Replacement ◽  
Major Complication ◽  
Dual Model ◽  
Joint Replacement Surgery ◽  
Pro Inflammatory Cytokines ◽  
Macrophage Membrane

Abstract Background：Inflammatory osteolysis is a major complication of total joint replacement surgery that can cause prosthesis failure and necessitate revision surgery. Macrophages are key effector immune cells in inflammatory responses, but excessive M1-polarization of dysfunctional macrophages leads to the secretion of pro-inflammatory cytokines and severe loss of bone tissue. Here, we report the development of macrophage-biomimetic porous SiO2-coated ultrasmall Se particles (Porous Se@SiO2 nanospheres) for the management of inflammatory osteolysis. Results: Macrophage-membrane-coated porous Se@SiO2 nanospheres(M-Se@SiO2) can attenuate lipopolysaccharide (LPS)-induced inflammatory osteolysis by a dual-immunomodulatory effect. As macrophage membrane decoys, these nanoparticles reduce toxin levels and neutralize pro-inflammatory cytokines. Moreover, the release of Se can induce the polarization of macrophages toward the anti-inflammatory M2-phenotype. These effects are mediated via the inhibition of p65, p38, and extracellular signal-regulated kinase(ERK) signaling. Additionally, the immune environment created by M-Se@SiO2 reduces the inhibition of osteogenic differentiation caused by pro-inflammation cytokines, confirmed through in vitro and in vivo experiments.Conclusion: Our findings suggest that M-Se@SiO2 has an immunomodulatory role in LPS-induced inflammation and bone remodeling, which demonstrates that M-Se@SiO2 is a promising engineered nano-platform for the treatment of osteolysis arising after arthroplasty.

Glucagon-like Peptide 1 Receptor Agonists, Diabetic Retinopathy and Angiogenesis: The AngioSafe Type 2 Diabetes Study

2019 ◽  
Vol 105 (4) ◽  
pp. e1549-e1560 ◽  
Author(s):  
Bénédicte Gaborit ◽  
Jean-Baptiste Julla ◽  
Samaher Besbes ◽  
Matthieu Proust ◽  
Clara Vincentelli ◽  
...  
Keyword(s):  
Type 2 Diabetes ◽  
Diabetic Retinopathy ◽  
Fundus Photography ◽  
Endothelial Cell Proliferation ◽  
Receptor Agonists ◽  
Glucagon Like Peptide ◽  
Glucagon Like Peptide 1

Abstract Aims Recent trials provide conflicting results on the association between glucagon-like peptide 1 receptor agonists (GLP-1RA) and diabetic retinopathy (DR). The aim of the AngioSafe type 2 diabetes (T2D) study was to determine the role of GLP-1RA in angiogenesis using clinical and preclinical models. Methods We performed two studies in humans. In study 1, we investigated the effect of GLP-1RA exposure from T2D diagnosis on the severity of DR, as diagnosed with retinal imaging (fundus photography). In study 2, a randomized 4-week trial, we assessed the effect of liraglutide on circulating hematopoietic progenitor cells (HPCs), and angio-miRNAs. We then studied the experimental effect of Exendin-4, on key steps of angiogenesis: in vitro on human endothelial cell proliferation, survival and three-dimensional vascular morphogenesis; and in vivo on ischemia-induced neovascularization of the retina in mice. Results In the cohort of 3154 T2D patients, 10% displayed severe DR. In multivariate analysis, sex, disease duration, glycated hemoglobin (HbA1c), micro- and macroangiopathy, insulin therapy and hypertension remained strongly associated with severe DR, while no association was found with GLP-1RA exposure (o 1.139 [0.800–1.622], P = .47). We further showed no effect of liraglutide on HPCs, and angio-miRNAs. In vitro, we demonstrated that exendin-4 had no effect on proliferation and survival of human endothelial cells, no effect on total length and number of capillaries. Finally, in vivo, we showed that exendin-4 did not exert any negative effect on retinal neovascularization. Conclusions The AngioSafe T2D studies provide experimental and clinical data confirming no effect of GLP-1RA on angiogenesis and no association between GLP-1 exposure and severe DR.

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