Mus musculus
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ABSTRACT:
PROVIDER: PRJNA387121 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Sema6D reverse signaling controls lipid metabolism for macrophage polarization linking mTOR to PPARγ
| PRJNA387120 | ENA
Project description:Obesity-associated insulin resistance is characterized by a state of chronic, low-grade inflammation that is associated with the accumulation of M1 proinflammatory macrophages in adipose tissue. Although different evidence explains the mechanisms linking the expansion of adipose tissue and adipose tissue macrophage (ATM) polarization, in the current study we investigated the concept of lipid-induced toxicity as the pathogenic link that could explain the trigger of this response. We addressed this question using isolated ATMs and adipocytes from genetic and diet-induced murine models of obesity. Through transcriptomic and lipidomic analysis, we created a model integrating transcript and lipid species networks simultaneously occurring in adipocytes and ATMs and their reversibility by thiazolidinedione treatment. We show that polarization of ATMs is associated with lipid accumulation and the consequent formation of foam cell–like cells in adipose tissue. Our study reveals that early stages of adipose tissue expansion are characterized by M2-polarized ATMs and that progressive lipid accumulation within ATMs heralds the M1 polarization, a macrophage phenotype associated with severe obesity and insulin resistance. Furthermore, rosiglitazone treatment, which promotes redistribution of lipids toward adipocytes and extends the M2 ATM polarization state, prevents the lipid alterations associated with M1 ATM polarization. Our data indicate that the M1 ATM polarization in obesity might be a macrophage-specific manifestation of a more general lipotoxic pathogenic mechanism. This indicates that strategies to optimize fat deposition and repartitioning toward adipocytes might improve insulin sensitivity by preventing ATM lipotoxicity and M1 polarization. 15 samples; 2 genotypes and 2 time points
2012-03-22 | E-GEOD-36669 | biostudies-arrayexpress
Project description:Type 2 diabetes mellitus (T2DM), characterized by hyperglycemia and dyslipidemia leads to non-proliferative diabetic retinopathy (NPDR). NPDR is associated with blood-retinal barrier disruption, plasma exudates, microvascular degeneration, elevated inflammatory cytokine levels and monocyte (Mo) infiltration. Whether and how the diabetes-associated changes in plasma lipid and carbohydrate levels modify Mo differentiation. Here, we show that mononuclear phagocytes (MPs) in areas of vascular leakage in DR donor retinas express PLIN2, a marker of intracellular lipid load. Strong upregulation of PLIN2 was also observed when healthy donor Mos were treated with plasma from T2DM patients or with palmitate concentrations typical of T2DM plasma, but not under high glucose conditions. PLIN2 expression correlated with the expression of other key genes involved in lipid metabolism (ACADVL, PDK4) and the DR biomarkers ANGPTL4 and CXCL8. Mechanistically, we show that lipid-exposed MPs induce capillary degeneration in ex vivo explants, which was inhibited by pharmaceutical inhibition of PPARγ signaling. Our study provides a novel mechanism linking dyslipidemia-induced MP polarization to the increased inflammatory cytokine levels and microvascular degeneration that characterize NPDR. This study provides comprehensive insights into the glycemia-independent activation of Mos in T2DM and identifies MP PPARγ as a target to inhibit lipid-activated MPs in DR
2023-08-31 | GSE239512 | GEO
Project description:The lipid-metabolism up-regulation-mediated M2 polarization provides tumor-associated macrophages (TAMs) with protumor phenotypes during tumor development and progression. However, how TAMs reprogram their lipid-metabolism responding to M2 activators remains unclear. Here, we report that S100A4 is a determinant of macrophage M2 polarization. We find that the growth of carcinoma grafts was impaired in myeloid S100A4-deficient mice. Coincidentally, ablating S100A4 in macrophages reduced their capability of macrophage into utilization utilize of exogenous fatty acids as their major energy source for oxidation. Mechanistic analysis demonstrates that the induction of PPAR-γ responding to Th2 cytokine, IL-4, was halted in s100a4-deleted TAMs, as well as in bone marrow-derived macrophages, and as well as in Raw264.7 cells. Further molecular analyses reveal that CD36, downstream from S100A4-PPARγ, is the major effector for lipid uptake of S100A4+ macrophages. FurthermoreImportantly, higher levels of S100A4 is closely associated with tumor resistance to chemotherapy in murine models as well as poor prognosis of cancer patients in clinic . Our study thus suggests that blocking S100A4 constitutes a treatment strategy to reprogram macrophages toward an antitumor state by inhibiting PPAR-γ-induction mediated gene up-regulation.
2021-06-30 | GSE161060 | GEO
Project description:Mendelian diseases that present with immune-mediated disorders can provide insights into the molecular mechanisms that drive inflammation. Hermansky-Pudlak syndrome (HPS) types 1 and 4 are caused by defective vesicle trafficking involving the BLOC-3 complex. The presence of inflammatory complications such as Crohn’s disease-like inflammation and lung fibrosis in these patients remains enigmatic. Using mass cytometry we observe an augmented inflammatory monocyte compartment in HPS1 patient peripheral blood that may be associated with a TNF - and IL-1α-dominated cytokine dysregulation. HPS1 patient monocyte-derived macrophages express an inflammatory TNF-OSM mRNA gene signature and changes in lipid metabolism. Using stimulation experiments and lysosomal proteomics we show that defective lipid metabolism drives RAB32-dependent mTOR signaling, facilitated by the accumulation of mTOR on lysosomes. This pathogenic circuit translates into aberrant bacterial clearance, which can be rescued with mTORC1 inhibition. We reveal that a pathogenic lipid-mTOR signaling circuit acts as a metabolic checkpoint for defective anti-microbial activity. This mechanism may be relevant to the complex pathology of HPS1 patients featuring macrophage lipid accumulation, granuloma formation, defective anti-microbial activity and tissue inflammation. Lastly, this circuit may be present in a wider group of disorders with defective lipid metabolism and cholesterol accumulation.
| EGAS00001005053 | EGA
Project description:Mendelian diseases that present with immune-mediated disorders can provide insights into the molecular mechanisms that drive inflammation. Hermansky-Pudlak syndrome (HPS) types 1 and 4 are caused by defective vesicle trafficking involving the BLOC-3 complex. The presence of inflammatory complications such as Crohn’s disease-like inflammation and lung fibrosis in these patients remains enigmatic. Using mass cytometry we observe an augmented inflammatory monocyte compartment in HPS1 patient peripheral blood that may be associated with a TNF - and IL-1α-dominated cytokine dysregulation. HPS1 patient monocyte-derived macrophages express an inflammatory TNF-OSM mRNA gene signature and changes in lipid metabolism. Using stimulation experiments and lysosomal proteomics we show that defective lipid metabolism drives RAB32-dependent mTOR signaling, facilitated by the accumulation of mTOR on lysosomes. This pathogenic circuit translates into aberrant bacterial clearance, which can be rescued with mTORC1 inhibition. We reveal that a pathogenic lipid-mTOR signaling circuit acts as a metabolic checkpoint for defective anti-microbial activity. This mechanism may be relevant to the complex pathology of HPS1 patients featuring macrophage lipid accumulation, granuloma formation, defective anti-microbial activity and tissue inflammation. Lastly, this circuit may be present in a wider group of disorders with defective lipid metabolism and cholesterol accumulation.
| EGAS00001005098 | EGA
Project description:Obesity-associated insulin resistance is characterized by a state of chronic, low-grade inflammation that is associated with the accumulation of M1 proinflammatory macrophages in adipose tissue. Although different evidence explains the mechanisms linking the expansion of adipose tissue and adipose tissue macrophage (ATM) polarization, in the current study we investigated the concept of lipid-induced toxicity as the pathogenic link that could explain the trigger of this response. We addressed this question using isolated ATMs and adipocytes from genetic and diet-induced murine models of obesity. Through transcriptomic and lipidomic analysis, we created a model integrating transcript and lipid species networks simultaneously occurring in adipocytes and ATMs and their reversibility by thiazolidinedione treatment. We show that polarization of ATMs is associated with lipid accumulation and the consequent formation of foam cell–like cells in adipose tissue. Our study reveals that early stages of adipose tissue expansion are characterized by M2-polarized ATMs and that progressive lipid accumulation within ATMs heralds the M1 polarization, a macrophage phenotype associated with severe obesity and insulin resistance. Furthermore, rosiglitazone treatment, which promotes redistribution of lipids toward adipocytes and extends the M2 ATM polarization state, prevents the lipid alterations associated with M1 ATM polarization. Our data indicate that the M1 ATM polarization in obesity might be a macrophage-specific manifestation of a more general lipotoxic pathogenic mechanism. This indicates that strategies to optimize fat deposition and repartitioning toward adipocytes might improve insulin sensitivity by preventing ATM lipotoxicity and M1 polarization.
2012-03-22 | GSE36669 | GEO
Project description:Macrophages form a primary immune cells population in tumor tissues and malignant ascites microenvironment (MAM). They can be activated and polarized into tumor-associated macrophages (TAM) by the embedded environment and promote tumor progression and metastasis However, the molecular mechanisms of MAM in macrophage polarization and the effects on epithelial ovarian cancer (EOC) metastatic progression remain elusive. Here, we found that that MAM modulates RhoA-GTPase-F-actin-Hippo signaling cascade in facilitating M2-like macrophage polarization that, in turn, promotes tumor dissemination. PUFA enriched magligant ascites microenvironment promote macrophage lipid oxidative phosphorylation and supression RhoA-GTPase-Yap1 axis. Genetic ablation Yap1 in macrophage exhibited M2-like polarization and enhanced ovrian tumor dissemination. Pharmacology inhibit Mst1/2 could rescue M2-like TAM polarization in MAM and alter the lipid oxidation of macrophages in MAM, more importantly, inhibit ovarian metastatic properties. Through comparasion primary TAM (P-TAM) and metastasis TAM (M-TAM), we proved that Hippo-Yap1 siganl results M-TAM with high M2/M1 ratio. These findings implicate critical functions of PUFA modulate RhoA-Hippo axis in facility TAM polarization and also suggest manipulation of PUFA metabolism or RhoA-Hippo siganl as a therapeutic strategy aganist EOC metastasis.
2024-05-01 | GSE175552 | GEO
Project description:PPARγ controls alveolar macrophage identity [part2]
| PRJNA257839 | ENA