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Kyle, J.

Publications and source records attributed to Kyle, J..

6 recordsLinked to original sources

CD248 activates TGF-β receptor I to promote vascular remodeling in pulmonary arterial hypertension

I.BackgroundPulmonary arterial hypertension (PAH) is a debilitating cardiopulmonary disease characterized by progressive remodeling of the pulmonary vasculature. Pathologic transforming growth factor-{beta} (TGF-{beta}) signaling is an essential driver of vascular remodeling in PAH. While global inhibitors of TGF-{beta} exist, their clinical application is limited by systemic adverse effects. Therefore, a critically unmet need in PAH is to identify pulmonary vascular-specific regulators of the TGF-{beta} axis, which would selectively enhance clinical efficacy while minimizing adverse effects. As the clinical care of PAH largely promotes vasodilation, and only one FDA-approved agent targets vascular remodeling, this study aimed to identify selective, therapeutically targetable regulators of the TGF-{beta} axis in the PAH pulmonary vasculature. MethodsCD248 was identified via liquid chromatography-tandem mass spectrometry (LC-MS/MS) proteomics in human lungs. CD248 levels were assessed across human, rat, and mouse lung tissues using western blotting, RTqPCR, and/or immunofluorescence techniques. CD248-null (CD248-/-) mice were used to study the contribution of CD248 to hypoxia-sugen (H/S)-induced PAH. The mechanistic role of CD248 in PAH vascular remodeling and TGF-{beta} signaling was assessed by genetic (siRNA knockdown; overexpression) and pharmacologic (Ontuxizumab) manipulation of primary human pulmonary vascular cells. ResultsLC-MS/MS proteomics coupled with pathway enrichment analysis of human lung tissue identified CD248 as a putative mediator of vascular remodeling that is elevated in PAH lungs. CD248 was elevated in PAH pulmonary artery smooth muscle cells (PASMCs) across human, rat, and mouse lung tissue. CD248-/- mice were protected from H/S-induced elevations in right ventricular (RV) systolic pressure (RVSP), RV hypertrophy, and pulmonary artery muscularization. CD248 knock-down reduced cell proliferation and migration of primary PAH PASMCs. CD248 was essential for phospho-activation of TGF-{beta} receptor I (T{beta}RI) at S165 and canonical phosphorylation of SMAD3 at S423/425. CD248 loss blunted TGF-{beta}-induced gene expression (FN1, Col11, -SMA) and activated expression of the vasoprotective matrix metalloprotease, MMP-8. Mechanistically, CD248 interacted with and enhanced de novo phosphorylation and stability of T{beta}RI, blocking its ubiquitin-mediated proteasomal degradation. Ontuxizumab promoted T{beta}RI instability and attenuated the production of FN1, Col11, and -SMA in primary PAH PASMCs. ConclusionsThis work identifies CD248 as a previously unrecognized co-activator of T{beta}RI in PAH. As CD248 is largely quiescent in most adult tissues yet pathologically upregulated in the PAH pulmonary vasculature, this study supports the potential of anti-CD248 therapy as a novel pulmonary vascular-specific alternative to systemic TGF-{beta} inhibition.

molecular biology↗

Dysregulation of lung epithelial cell homeostasis and immunity contributes to Middle East Respiratory Syndrome coronavirus disease severity

Coronaviruses (CoV) emerge suddenly from animal reservoirs to cause novel diseases in new hosts. Discovered in 2012, Middle East respiratory syndrome coronavirus (MERS-CoV) is endemic in camels in the Middle East and is continually causing local outbreaks and epidemics. While all three newly emerging human CoV from past 20 years (SARS-CoV, SARS-CoV-2, MERS-CoV) cause respiratory disease, each CoV has unique host interactions that drive differential pathogeneses. To better understand the virus and host interactions driving lethal MERS-CoV infection, we performed a longitudinal multi-omics analysis of sublethal and lethal MERS-CoV infection in mice. Significant differences were observed in body weight loss, virus titers and acute lung injury among lethal and sub-lethal virus doses. Virus induced apoptosis of type I and II alveolar epithelial cells suggest that loss or dysregulation of these key cell populations was a major driver of severe disease. Omics analysis suggested differential pathogenesis was multi-factorial with clear differences among innate and adaptive immune pathways as well as those that regulate lung epithelial homeostasis. Infection of mice lacking functional T and B-cells showed that adaptive immunity was important in controlling viral replication but also increased pathogenesis. In summary, we provide a high-resolution host response atlas for MERS-CoV infection and disease severity. Multi-omics studies of viral pathogenesis offer a unique opportunity to not only better understand the molecular mechanisms of disease but also to identify genes and pathways that can be exploited for therapeutic intervention all of which is important for our future pandemic preparedness. ImportanceEmerging coronaviruses like SARS-CoV, SARS-CoV-2 and MERS-CoV cause a range of disease outcomes in humans from asymptomatic, moderate and severe respiratory disease which can progress to death but the factors causing these disparate outcomes remain unclear. Understanding host responses to mild and life-threatening infection provides insight into virus-host networks within and across organ systems that contribute to disease outcomes. We used multi-omics approaches to comprehensively define the host response to moderate and severe MERS-CoV infection. Severe respiratory disease was associated with dysregulation of the immune response. Key lung epithelial cell populations that are essential for lung function get infected and die. Mice lacking key immune cell populations experienced greater virus replication but decreased disease severity implicating the immune system in both protective and pathogenic roles in the response to MERS-CoV. These data could be utilized to design new therapeutic strategies targeting specific pathways that contribute to severe disease.

microbiology↗

Changes in maternal blood and placental lipidomic profile in obesity and gestational diabetes: Evidence for sexual dimorphism

IntroductionObesity and gestational diabetes (GDM) are associated with adverse pregnancy outcomes and program the offspring for cardiometabolic disease in a sexually dimorphic manner. The placenta transfers lipids to the fetus and uses these substrates to support its own metabolism impacting the amount of substrate available to the growing fetus. MethodsWe collected maternal plasma and placental villous tissue following elective cesarean section at term from women who were lean (pre-pregnancy BMI 18.5-24.9), obese (BMI>30) and type A2 GDM (matched to obese BMI) with male or female fetus (n=4 each group). Lipids were extracted and fatty acid composition of different lipid classes were analyzed by LC-MS/MS analysis. Significant changes in GDM vs obese, GDM vs lean, and obese vs lean were determined using t-test with a Tukey correction set at p<0.05. ResultsIn placental samples 436 lipids were identified, among which 85 showed significant changes. Of note only in male placentas significant decreases in C22:6 - docosahexaenoic acid (DHA) in phosphatidylcholine (PC) and triglyceride lipid species were seen when comparing tissue from GDM women to lean. In maternal plasma we observed no effect of obesity. GDM or fetal sex. ConclusionThis is the first study assessing fatty acid composition of lipids in matched maternal plasma and placental tissue from lean, obese, and GDM women stratified by fetal sex. It highlights how GDM affects distribution of fatty acids in lipid classes changes in a sexually dimorphic manner in the placenta.

molecular biology↗

A global lipid map reveals host dependency factors conserved across SARS-CoV-2 variants

A comprehensive understanding of host dependency factors for SARS-CoV-2 remains elusive. We mapped alterations in host lipids following SARS-CoV-2 infection using nontargeted lipidomics. We found that SARS-CoV-2 rewires host lipid metabolism, altering 409 lipid species up to 64-fold relative to controls. We correlated these changes with viral protein activity by transfecting human cells with each viral protein and performing lipidomics. We found that lipid droplet plasticity is a key feature of infection and that viral propagation can be blocked by small-molecule glycerolipid biosynthesis inhibitors. We found that this inhibition was effective against the main variants of concern (alpha, beta, gamma, and delta), indicating that glycerolipid biosynthesis is a conserved host dependency factor that supports this evolving virus.

microbiology↗

Root carbon interaction with soil minerals is dynamic, leaving a legacy of microbially-derived residues

1.Minerals preserve the oldest most persistent soil carbon, and mineral characteristics appear to play a critical role in the formation of soil organic matter (SOM) associations. To test the hypothesis that carbon source and soil microorganisms also influence mineral-SOM associations, we incubated permeable minerals bags in soil microcosms with and without plants, in a 13CO2 labeling chamber. Mineral bags contained quartz, ferrihydrite, kaolinite, or native soil minerals isolated via density separation. Using 13C-NMR, FTICR-MS, and lipidomics, we traced plant-derived carbon onto minerals harvested from microcosms at three plant growth stages, characterizing total carbon, 13C enrichment, and SOM chemistry. While C accumulation was rapid and mineral-dependent, the accumulated amount was not significantly affected by the presence of plant roots. However, the rhizosphere did shape the chemistry of mineral-associated SOM. Minerals incubated in the rhizosphere were associated with a more diverse array of compounds with different C functional groups (carbonyl, aromatics, carbohydrates, lipids) than minerals incubated in a bulk soil control. These diverse rhizosphere-derived compounds may represent a "transient fraction" of mineral SOM, rapidly exchanging with mineral surfaces. Our results also suggest that many of the lipids which persist on minerals are microbially-derived with a large fraction of fungal lipids. SynopsisThis study explores the interaction of rhizosphere carbon, minerals, and microbial influence on the fate of soil carbon. TOC O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=184 SRC="FIGDIR/small/436628v1_ufig1.gif" ALT="Figure 1"> View larger version (52K): org.highwire.dtl.DTLVardef@17ce1bborg.highwire.dtl.DTLVardef@1c7c2e8org.highwire.dtl.DTLVardef@1cd0e41org.highwire.dtl.DTLVardef@162ff90_HPS_FORMAT_FIGEXP M_FIG C_FIG

ecology↗

The role of islet lipid composition remodeling in regulation of beta-cell death via ADP-ribosyl-acceptor glycohydrolase ARH3 signaling in insulitis

Lipids have been implicated as mediators of insulitis and {beta}-cell death in type 1 diabetes development, but the mechanisms underlying this association are poorly understood. Here, we investigated the changes in islet/{beta}-cell lipid composition using three models of insulitis: human islets and EndoC-{beta}H1 {beta}-cells treated with the cytokines IL-1{beta} and IFN-{gamma}, and islets from non-obese diabetic mice. Across all three models, lipidomic analyses showed a consistent change in abundance of the lysophosphatidylcholine, phosphatidylcholine and triacylglycerol species. We also showed that lysophosphatidylcholine and its biosynthetic enzyme PLA2G6 are enriched in murine islets. We determined that the ADP-ribosyl-acceptor glycohydrolase ARH3 is regulated by cytokines downstream of PLA2G6, which in turn regulates proteins involved in apoptosis, lipid metabolism, antigen processing and presentation and chemokines. ARH3 reduced cytokine-induced apoptosis, which may represent a negative feedback mechanism. Overall, these data show the importance of lipid metabolism in regulating {beta}-cell death in type 1 diabetes. HighlightsO_LILipidomics of 3 insulitis models revealed commonly regulated lipid classes. C_LIO_LIIdentification of 35 proteins regulated by cytokines via PLA2G6 signaling. C_LIO_LIARH3 reduces cytokine-induced apoptosis via PLA2G6 regulation. C_LIO_LIARH3 regulates the levels of proteins related to insulitis and type 1 diabetes. C_LI

systems biology↗