bioRxiv Science⌕ Search

Biology subjects

Doering, Y.

Publications and source records attributed to Doering, Y..

6 recordsLinked to original sources

The ApoC2 mimetic peptide D6PV enhances remyelination by stimulating oxidative phosphorylation in oligodendrocytes

Failure of remyelination drives neurodegeneration in demyelinating disorders such as multiple sclerosis (MS), with disrupted lipid handling and metabolic stress in oligodendrocyte precursor cells (OPCs) posing major barriers to repair. Here, we identify the dual ApoC-II mimetic-ApoC-III antagonist peptide D6PV as a metabolic modulator that directly enhances OPC differentiation and myelin repair. Across ex vivo and in vivo models of chemically induced demyelination, D6PV promotes oligodendrocyte maturation and restores myelin integrity independently of lipoprotein hydrolysis or modulation of lipid droplet-containing phagocytes. Guided by transcriptomics analyses, we find that D6PV stimulates mitochondrial oxidative phosphorylation and fatty acid {beta}-oxidation, while suppressing inflammatory transcriptional programs, thereby driving OPCs toward a myelinating phenotype. Notably, D6PV does not alter peripheral immune composition or autoimmune-driven pathology in the experimental autoimmune encephalomyelitis model, indicating a central nervous system (CNS) cell-autonomous effect. These findings reveal a metabolism-linked pathway for remyelination and position D6PV as a promising therapeutic strategy to enhance CNS repair in demyelinating diseases.

neuroscience↗

Neural CXCR4 contributes to neuroimmune modulation of atherosclerosis in a cardio-metabolic Ldlr-/- mouse model

BackgroundAtherosclerosis is a chronic inflammatory disease characterized by metabolic and immune dysregulation. Emerging evidence suggests that specific central nervous system (CNS) regions modulate its progression via neuroimmune cardiovascular interfaces (NICIs). While the C-X-C motif chemokine receptor 4 (CXCR4) is known to participate in atherogenesis by regulating immune cell dynamics and vascular wall responses, the role of neural CXCR4 in atherosclerotic plaque formation remains unclear. MethodsWe generated a Nestin-Cre-mediated conditional Cxcr4 knockout mouse model on a low-density lipoprotein receptor-deficient (Ldlr-/-) background and fed these mice a western diet (WD) for up to 12 weeks to induce atherosclerosis. To evaluate the impact of neural CXCR4 function, we quantified atherosclerotic plaque burden, systemic metabolic parameters and circulating immune cell profiles, comparing neural Cxcr4-deficient mice with corresponding genetic controls. Spatial transcriptomics and RNAscope were employed to map Cxcr4 mRNA and its non-canonical ligand macrophage migration inhibitory factor (Mif) mRNA in neuroimmune-regulatory brain regions, and to assess diet-induced expression changes in relation to neuroinflammatory responses. ResultsNeural conditional deletion of Cxcr4 in Ldlr-/- mice significantly reduced atherosclerotic plaque formation in the aortic arch and aorta, without affecting body weight, lipid levels, glucose tolerance, or circulating immune cells. Cxcr4 gene expression was found to be uniformly low across hypothalamic subregions implicated in neuroimmune regulation of systemic inflammation and atherogenesis. Importantly, WD feeding did not modify this consistently low expression in male Ldlr-/- mice. In contrast, Mif mRNA expression was significantly upregulated in the PVN after 5-day WD feeding, but not after 8 weeks. Exploratory spatial transcriptomic analysis of PVN-containing coronal brain sections from male Ldlr-/- mice suggested that 5-day WD exposure is associated with MIF-CXCR4 signaling and downstream neuroinflammatory pathways in the PVN. ConclusionsThis study identifies neural CXCR4 as a component of neuroimmune modulation in atherosclerosis, exerting its effect independently of systemic metabolic or inflammatory changes. Short-term WD exposure activated gene expression of the CXCR4 ligand Mif in the PVN, pointing to a neuroimmune axis that may promote vascular inflammation and atherosclerotic plaque development. These findings establish a link between CNS CXCR4 and vascular disease and suggest that MIF-CXCR4-dependent neuroimmune pathways may play a role in cardiometabolic risk. Trial registrationNot applicable.

immunology↗

Galectin-1 induces macrophage immunometabolic reprogramming, modulates T cell immunity and attenuates atherosclerotic plaque formation

Background and aimsAtherosclerosis is a chronic immunometabolic disease driven by lipid accumulation and immune cell infiltration. Macrophages and T cells play key roles throughout plaque development. Galectin-1 (Gal-1), a glycan-binding protein, modulates immune functions in these cells and has been reported to attenuate atherosclerosis, though its mechanisms remain incompletely understood. Here, we investigated the effects of Gal-1 on macrophages and T cells during plaque formation. MethodsEffects of Gal-1 on atherosclerosis, macrophages and T cells during lesion formation were studied in Apoe-/- mice treated with recombinant Gal-1. Complementary mouse peritoneal foam cell and in vitro macrophage and T cell cultures experiments were performed to study T cell differentiation, macrophage function, polarization end energy metabolism. The impact of Gal-1 on human macrophages was further evaluated in endarterectomy specimens. ResultsGal-1 treatment reduced lesion size and increased circulating IL-10 levels, inversely correlating with plaque burden. Unexpectedly, IL-10 neutralization also mitigated atherosclerosis, indicating that its action is at least partially IL-10-independent. In plaques, Gal-1 promoted anti-inflammatory macrophage phenotypes, mirrored by a quiescent metabolic and anti-inflammatory profile in foamy macrophages ex vivo. The use of the Gal-1E71Q variant revealed that these effects were only partly dependent on glycan binding. Beyond IL-10, Gal-1 reshaped cytokine profiles by increasing IL-17, IL-22, and IL-23, consistent with a macrophage-driven regulatory Th17 response, alongside higher frequencies of IL-10-producing and regulatory T cells. ConclusionGal-1 protects against atherosclerosis associated with reprogramming macrophages and tuning T cell immunity through glycan-dependent and -independent pathways.

immunology↗

Cigarette smoking upregulates vascular expression of the novel atherosclerosis risk factor ADAMTS-7

BackgroundCigarette smoking is an established risk factor for coronary artery disease (CAD) and myocardial infarction. Genetic variants in the extracellular matrix protease ADAMTS-7 were also identified to increase CAD risk. Notably, ADAMTS7 represents the only genomic locus that revealed a gene-environment interaction with smoking. The underlying mechanisms of this interaction remain unclear. Methods and ResultsIn a murine model, cigarette smoke exposure (CSE) led to an upregulation of vascular ADAMTS7 expression in wild type (WT) C57BL/6J mice. ADAMTS7 upregulation was also found in carotid plaques from ever-smokers undergoing carotid endarterectomy in humans. Bulk RNA sequencing of lung tissues from WT mice exposed to CS revealed a downregulation of 20 and an upregulation of 173 transcripts. Among upregulated transcripts in smoking-exposed lungs, we found C-C motif chemokine ligand 17 (CCL17), which was likewise upregulated in plasma from smoking mice and humans. In vitro, recombinant CCL17 upregulated ADAMTS7 expression in primary vascular smooth muscle cells (VSMC), which was inhibited secondary to silencing of CCL17s bona fide receptor C-C Motif Chemokine Receptor 4 (CCR4). Conditioned media from CCL17-stimulated VSMC lacking ADAMTS-7 showed reduced release of inflammatory cytokines by endothelial cells (EC), reduced EC activation, and monocyte-to-EC adhesion. In proatherogenic Apoe-/- mice exposed to CS, more numerous neutrophils, inflammatory monocytes, and macrophages were found in atherosclerotic plaques as compared to room air exposition. This effect was blunted in Apoe-/-Adamts7-/- mice. ConclusionsFor the first time, our findings link CSE to vascular inflammation via CCL17-mediated upregulation of the CAD risk factor ADAMTS7 and provide a mechanistic explanation for the gene-environment interaction between CS and ADAMTS7 in CAD. Targeting ADAMTS-7 might be a promising therapeutic strategy irrespective of smoking status. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=85 SRC="FIGDIR/small/685237v1_ufig1.gif" ALT="Figure 1"> View larger version (16K): org.highwire.dtl.DTLVardef@1d8366eorg.highwire.dtl.DTLVardef@1dda3feorg.highwire.dtl.DTLVardef@39a4bcorg.highwire.dtl.DTLVardef@6e58b6_HPS_FORMAT_FIGEXP M_FIG C_FIG

physiology↗

MicroRNA-26b protects against MASH development and can be efficiently targeted with lipid nanoparticles.

Background & AimsThe prevalence of metabolic dysfunction-associated steatohepatitis (MASH) is increasing, urging more research into the underlying mechanisms. MicroRNA-26b (miR-26b) might play a role in several MASH-related pathways. Therefore, we aimed to determine the role of miR-26b in MASH and its therapeutic potential using miR-26b mimic-loaded lipid nanoparticles (LNPs). MethodsApoe-/-Mir26b-/-, Apoe-/-LysMcreMir26bfl/fl mice, and respective controls were fed a western-type diet to induce MASH. Plasma and liver samples were characterized regarding lipid metabolism, hepatic inflammation, and fibrosis. Additionally, miR-26b mimic-loaded LNPs were injected in Apoe-/-Mir26b-/- mice to rescue the phenotype and key results were validated in human precision-cut liver slices. Finally, kinase profiling was used to elucidate underlying mechanisms. ResultsApoe-/-Mir26b-/- mice showed increased hepatic lipid levels, coinciding with increased expression of scavenger receptor a and platelet glycoprotein 4. Similar effects were found in mice lacking myeloid-specific miR-26b. Additionally, hepatic TNF and IL-6 levels and amount of infiltrated macrophages were increased in Apoe-/- Mir26b-/- mice. Moreover, Tgfb expression was increased by the miR-26b deficiency, leading to more hepatic fibrosis. A murine treatment model with miR-26b mimic-loaded LNPs reduced hepatic lipids, rescuing the observed phenotype. Kinase profiling identified increased inflammatory signaling upon miR-26b deficiency, which was rescued by LNP treatment. Finally, miR-26b mimic-loaded LNPs also reduced inflammation in human precision-cut liver slices. ConclusionsOverall, our study demonstrates that the detrimental effects of miR-26b deficiency in MASH can be rescued by LNP treatment. This novel discovery leads to more insight into MASH development, opening doors to potential new treatment options using LNP technology. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=100 SRC="FIGDIR/small/580792v2_ufig1.gif" ALT="Figure 1"> View larger version (21K): org.highwire.dtl.DTLVardef@b8b5b8org.highwire.dtl.DTLVardef@a26333org.highwire.dtl.DTLVardef@11ed2a0org.highwire.dtl.DTLVardef@963208_HPS_FORMAT_FIGEXP M_FIG C_FIG

pathology↗

GIP receptor agonism improves dyslipidemia and atherosclerosis independently of body weight in obese mice

Agonism at the receptors for the glucose-dependent insulinotropic polypeptide (GIPR) is a key component of the novel unimolecular co-agonists which are among the most promising drugs in clinical development for the treatment of obesity and diabetes. The therapeutic effect of chronic GIPR agonism to treat dyslipidemia, and thus to reduce the cardiovascular disease risk, has not been explored yet. Herein we found that treatment with a long-acting acylated GIP analog (Acyl-GIP) reduced dyslipidemia and atherogenesis in male LDL receptor knockout mice. Acyl-GIP administration resulted in smaller adipocytes within the inguinal fat depot and RNAseq analysis of the latter revealed that Acyl-GIP may improve dyslipidemia by directly modulating lipid metabolism in this fat depot. This study identified an unanticipated efficacy of chronic GIPR agonist administration to improve dyslipidemia and cardiovascular disease.

pharmacology and toxicology↗