Targeting Gα in neutrophils protects from myocardial ischemia reperfusion injury.

Neutrophils are not only involved in immune defense against infection but also contribute to the exacerbation of tissue damage after ischemia and reperfusion. We have previously shown that genetic ablation of regulatory Gα proteins in mice has both protective and deleterious effects on myocardial ischemia reperfusion injury (mIRI), depending on which isoform is deleted. To deepen and analyze these findings in more detail the contribution of Gα proteins in resident cardiac vs circulating blood cells for mIRI was first studied in bone marrow chimeras.

Non-canonical G protein signaling.

The original paradigm of classical - also referred to as canonical - cellular signal transduction of heterotrimeric G proteins (G protein) is defined by a hierarchical, orthograde interaction of three players: the agonist-activated G protein-coupled receptor (GPCR), which activates the transducing G protein, that in turn regulates its intracellular effectors. This receptor-transducer-effector concept was extended by the identification of regulators and adapters such as the regulators of G protein signaling (RGS), receptor kinases like βARK, or GPCR-interacting arrestin adapters that are integrated into this canonical signaling process at different levels to enable fine-tuning. Finally, the identification of atypical signaling mechanisms of classical regulators, together with the discovery of novel modulators, added a new and fascinating dimension to the cellular G protein signal transduction.

G Protein-Coupled Receptors in Cell Signaling Transduction.

G protein-coupled receptors (GPCRs) and their downstream signaling pathways are critical targets for current pharmacotherapy [...

From an Hsp90 - binding protein to a peptide drug.

The Lpl proteins represent a class of lipoproteins that was first described in the opportunistic bacterial pathogen , where they contribute to pathogenicity by enhancing F-actin levels of host epithelial cells and thereby increasing internalization. The model Lpl protein, Lpl1 was shown to interact with the human heat shock proteins Hsp90α and Hsp90ß, suggesting that this interaction may trigger all observed activities. Here we synthesized Lpl1-derived peptides of different lengths and identified two overlapping peptides, namely, L13 and L15, which interacted with Hsp90α.

Depletion of Ly6G-Expressing Neutrophilic Cells Leads to Altered Peripheral T-Cell Homeostasis and Thymic Development in Neonatal Mice.

Newborns and especially preterm infants are much more susceptible to infections than adults. Due to immature adaptive immunity, especially innate immune cells play an important role in a newborn's infection defense. Neonatal neutrophils exhibit profound differences in their functionality compared to neutrophils of adults.

Impact of different immunosuppressive protocols on clinical outcomes in obese kidney transplant recipients: a propensity score-matched analysis.

Background: Although obesity has become a significant problem in transplantation medicine, the impact of different immunosuppressive protocols on clinical outcomes in obese transplant recipients remains unclear.

Methods: We performed an analysis of the Scientific Registry of Transplant Recipients database. Kidney transplant recipients were categorized according to body mass index (BMI) categories and immunosuppressive protocols: (i) tacrolimus/mycophenolate mofetil (Tac-MMF), (ii) mTOR-inhibitor/Tac (mTORi-Tac), (iii) mTORi/cyclosporin (mTORi-Cyc) and (iv) mTORi-MMF.

Data on common carotid artery occlusion inducing focalized stroke lesions after Pertussis toxin injection.

This article contains raw and processed data related to research published by Vega et al. (2022). This complementary dataset provides further insight into the experimental validation of a single common carotid artery occlusion (CCAO) model upon pretreatment with pertussis toxin (PTX).

Knockout of SLy1 decreases double-negative thymocyte proliferation and protects mice from p53-induced tumor formation.

The lymphocyte-specific adapter protein SLy1 has previously been identified as indispensable for thymocyte development and T-cell proliferation and, recently, as a cause of X-linked combined immunodeficiency in humans that recapitulates many of the abnormalities reported in SLy1 and SLy1 mice. As SLy1 NK cells show increased levels of p53, we focused our research on the interdependency of SLy1 and p53 for thymocyte development. Using RT-PCR and immunoblot analysis, we observed increased levels of p53 as well as DNA damage response proteins in SLy1 thymocytes.

Untargeted stable isotope-resolved metabolomics to assess the effect of PI3Kβ inhibition on metabolic pathway activities in a PTEN null breast cancer cell line.

The combination of high-resolution LC-MS untargeted metabolomics with stable isotope-resolved tracing is a promising approach for the global exploration of metabolic pathway activities. In our established workflow we combine targeted isotopologue feature extraction with the non-targeted XCMS routine. Metabolites, detected by XCMS as differentially labeled between two biological conditions are subsequently integrated into the original targeted library.

Platelets and the Cybernetic Regulation of Ischemic Inflammatory Responses through PNC Formation Regulated by Extracellular Nucleotide Metabolism and Signaling.

Ischemic events are associated with severe inflammation and are here referred to as ischemic inflammatory response (IIR). Recent studies identified the formation of platelet-neutrophil complexes (PNC) as key players in IIR. We investigated the role of extracellular platelet nucleotide signaling in the context of IIR and defined a cybernetic circle, including description of feedback loops.

Cerebrovascular G Proteins Protect Against Brain Hypoperfusion and Collateral Failure in Cerebral Ischemia.

Cerebral hypoperfusion and vascular dysfunction are closely related to common risk factors for ischemic stroke such as hypertension, dyslipidemia, diabetes, and smoking. The role of inhibitory G protein-dependent receptor (GPCR) signaling in regulating cerebrovascular functions remains largely elusive. We examined the importance of GPCR signaling in cerebral blood flow (CBF) and its stability after sudden interruption using various in vivo high-resolution magnetic resonance imaging techniques.

Awake Mouse fMRI and Pupillary Recordings in the Ultra-High Magnetic Field.

Awake rodent fMRI is becoming a promising non-invasive brain imaging module when investigating large-scale brain function given behavioral tasks. Previous studies have either applied sedatives during scanning or pre-treatment of anesthetics, e.g.

Myeloid-Derived Suppressor Cells Dampen Airway Inflammation Through Prostaglandin E2 Receptor 4.

Emerging evidence suggests a mechanistic role for myeloid-derived suppressor cells (MDSCs) in lung diseases like asthma. Previously, we showed that adoptive transfer of MDSCs dampens lung inflammation in murine models of asthma through cyclooxygenase-2 and arginase-1 pathways. Here, we further dissected this mechanism by studying the role and therapeutic relevance of the downstream mediator prostaglandin E2 receptor 4 (EP4) in a murine model of asthma.

Analyses of Gnai3-iresGFP reporter mice reveal unknown Gα expression sites.

Inhibitory G proteins (G proteins) are highly homologous but play distinct biological roles. However, their isoform-specific detection remains challenging. To facilitate the analysis of Gα expression, we generated a Gnai3- iresGFP reporter mouse line.

The gut microbiota metabolite urolithin A inhibits NF-κB activation in LPS stimulated BMDMs.

Inflammation is a natural defense process of the innate immune system, associated with the release of proinflammatory cytokines such as interleukin-1β, interleukin-6, interleukin-12 and TNFα; and enzymes including iNOS through the activation and nuclear translocation of NF-κB p65 due to the phosphorylation of IκBα. Regulation of intracellular Ca is considered a promising strategy for the prevention of reactive oxygen species (ROS) production and accumulation of DNA double strand breaks (DSBs) that occurs in inflammatory-associated-diseases. Among the metabolites of ellagitannins that are produced in the gut microbiome, urolithin A (UA) has received an increasing attention as a novel candidate with anti-inflammatory and anti-oxidant effects.

The emerging and diverse roles of the SLy/SASH1-protein family in health and disease-Overview of three multifunctional proteins.

Intracellular adaptor proteins are indispensable for the transduction of receptor-derived signals, as they recruit and connect essential downstream effectors. The SLy/SASH1-adaptor family comprises three highly homologous proteins, all of them sharing conserved structural motifs. The initial characterization of the first member SLy1/SASH3 (SH3 protein expressed in lymphocytes 1) in 2001 was rapidly followed by identification of SLy2/HACS1 (hematopoietic adaptor containing SH3 and SAM domains 1) and SASH1/SLy3 (SAM and SH3 domain containing 1).

SLy2-overexpression impairs B-cell development in the bone marrow and the IgG response towards pneumococcal conjugate-vaccine.

Background: Infections with Streptococcus pneumoniae can cause severe diseases in humans including pneumonia. Although guidelines for vaccination have been established, S. pneumoniae is still responsible for a serious burden of disease around the globe.

Enhanced IgG -mediated antibody response towards thymus-dependent immunization in CXCR1-deficient mice.

Background: Chemokine receptors and their corresponding ligands are key players of immunity by regulation of immune cell differentiation and migration. CXCR1 is a high-affinity receptor for CXCL8. Differential expression of CXCR1 is associated with a variety of human pathologies including cancer and inflammatory diseases.

SLy2-deficiency promotes B-1 cell immunity and triggers enhanced production of IgM and IgG antibodies against pneumococcal vaccine.

Background: Despite the benefits of existing vaccines, Streptococcus pneumoniae is still responsible for the greatest proportion of respiratory tract infections around the globe, thereby substantially contributing to morbidity and mortality in humans. B-1 cells are key players of bacterial clearance during pneumococcal infection and even provide long-lasting immunity towards S. pneumoniae.

Cell motility and migration as determinants of stem cell efficacy.

Background: Stem cells` (SC) functional heterogeneity and its poorly understood aetiology impedes clinical development of cell-based therapies in regenerative medicine and oncology. Recent studies suggest a strong correlation between the SC migration potential and their therapeutic efficacy in humans. Designating SC migration as a denominator of functional SC heterogeneity, we sought to identify highly migrating subpopulations within different SC classes and evaluate their therapeutic properties in comparison to the parental non-selected cells.

Selective protection of murine cerebral G-proteins from inactivation by parenterally injected pertussis toxin.

Pertussis toxin (PTX) is a potent virulence factor in patients suffering from whooping cough, but in its detoxified version, it is applied for vaccination. It is thought to contribute to the pathology of the disease including various CNS malfunctions. Based on its enzymatic activity, PTX disrupts GPCR-dependent signaling by modifying the α-subunit of heterotrimeric G-proteins.

Human monocytic myeloid-derived suppressor cells impair B-cell phenotype and function in vitro.

Myeloid-derived suppressor cells (MDSCs) are key regulators of immunity that initially have been defined by their ability to potently suppress T-cell responses. Recent studies collectively demonstrate that the suppressive activity of MDSCs is not limited to T cells, but rather affects a broad range of immune cell subsets. However, relatively few studies have assessed the impact of MDSCs on B cells, particularly in the human context.

Function, Regulation and Biological Roles of PI3Kγ Variants.

Phosphatidylinositide 3-kinase (PI3K) γ is the only class IB PI3K member playing significant roles in the G-protein-dependent regulation of cell signaling in health and disease. Originally found in the immune system, increasing evidence suggest a wide array of functions in the whole organism. PI3Kγ occur as two different heterodimeric variants: PI3Kγ (p87) and PI3Kγ (p101), which share the same p110γ catalytic subunit but differ in their associated non-catalytic subunit.

Intranasal Losartan Decreases Perivascular Beta Amyloid, Inflammation, and the Decline of Neurogenesis in Hypertensive Rats.

The contribution of the local angiotensin receptor system to neuroinflammation, impaired neurogenesis, and amyloid beta (Aβ) accumulation in Alzheimer's disease (AD) and in hypertension is consistent with the remarkable neuroprotection provided by angiotensin receptor blockers (ARBs) independent of their blood pressure-lowering effect. Considering the causal relationship between hypertension and AD and that targeting cerebrovascular pathology with ARBs does not necessarily require their systemic effects, we tested intranasal losartan in the rat model of chronic hypertension (spontaneously hypertensive stroke-prone rats, SHRSP). Intranasal losartan at a subdepressor dose decreased mortality, neuroinflammation, and perivascular content of Aβ by enhancing key players in its metabolism and clearance, including insulin-degrading enzyme, neprilysin, and transthyretin.

Macrophage Phosphoproteome Analysis Reveals MINCLE-dependent and -independent Mycobacterial Cord Factor Signaling.

Immune sensing of relies on recognition by macrophages. Mycobacterial cord factor, trehalose-6,6'-dimycolate (TDM), is the most abundant cell wall glycolipid and binds to the C-type lectin receptor (CLR) MINCLE. To explore the kinase signaling linking the TDM-MINCLE interaction to gene expression, we employed quantitative phosphoproteome analysis.