ABSTRACT
As fusion experiments at the National Ignition Facility (NIF) approach and exceed breakeven, energy from the burning capsule is predicted to couple to the gold walls and reheat the hohlraum. On December 5, 2022, experiment N221204 exceeded target breakeven, historically achieving 3.15 MJ of fusion energy from 2.05 MJ of laser drive; for the first time, energy from the igniting capsule reheated the hohlraum beyond the peak laser-driven radiation temperature of 313 eV to a peak of 350 eV, in less than half a nanosecond. This reheating effect has now been unambiguously observed by the two independent Dante calorimeter systems across multiple experiments, and is shown to result from reheating of the remnant tungsten-doped ablator by the exploding core, which is heated by alpha deposition.
ABSTRACT
Proper wound closure requires the functional coordination of endothelial cells (ECs) and keratinocytes. In the late stages of wound healing, keratinocytes become activated and ECs promote the maturation of nascent blood vessels. In diabetes mellitus, decreased keratinocyte activation and impaired angiogenic action of ECs delay wound healing. Porcine urinary bladder matrix (UBM) improves the rate of wound healing, but the effect of exposure to UBM under diabetic conditions remains unclear. We hypothesized that keratinocytes and ECs isolated from both diabetic and non-diabetic donors would exhibit a similar transcriptome representative of the later stages of wound healing following incubation with UBM. Human keratinocytes and dermal ECs isolated from non-diabetic and diabetic donors were incubated with and without UBM particulate. RNA-Seq analysis was performed to identify changes in the transcriptome of these cells associated with exposure to UBM. While diabetic and non-diabetic cells exhibited different transcriptomes, these differences were minimized following incubation with UBM. ECs exposed to UBM exhibited changes in the expression of transcripts suggesting an increase in the endothelial-mesenchymal transition (EndoMT) associated with vessel maturation. Keratinocytes incubated with UBM demonstrated an increase in markers of activation. Comparison of the whole transcriptomes with public datasets suggested increased EndoMT and keratinocyte activation following UBM exposure. Both cell types exhibited loss of pro-inflammatory cytokines and adhesion molecules. These data suggest that application of UBM may accelerate healing by promoting a transition to the later stages of wound healing. This healing phenotype is achieved in cells isolated from both diabetic and non-diabetic donors.
Subject(s)
Diabetes Mellitus , Transcriptome , Humans , Swine , Animals , Urinary Bladder , Endothelial Cells , Keratinocytes/metabolism , Wound HealingABSTRACT
BACKGROUND: Atherosclerosis is a common co-morbidity of type 2 diabetes mellitus. Monocyte recruitment by an activated endothelium and the pro-inflammatory activity of the resulting macrophages are critical components of atherosclerosis. Exosomal transfer of microRNAs has emerged as a paracrine signaling mechanism regulating atherosclerotic plaque development. MicroRNAs-221 and -222 (miR-221/222) are elevated in vascular smooth muscle cells (VSMCs) of diabetic patients. We hypothesized that the transfer of miR-221/222 via VSMC-derived exosomes from diabetic sources (DVEs) promotes increased vascular inflammation and atherosclerotic plaque development. METHODS: Exosomes were obtained from VSMCs, following exposure to non-targeting or miR-221/-222 siRNA (-KD), isolated from diabetic (DVEs) and non-diabetic (NVEs) sources and their miR-221/-222 content was measured using droplet digital PCR (ddPCR). Expression of adhesion molecules and the adhesion of monocytes was measured following exposure to DVEs and NVEs. Macrophage phenotype following exposure to DVEs was determined by measuring mRNA markers and secreted cytokines. Age-matched apolipoprotein-E-deficient mice null (ApoE-/-) mice were maintained on Western diet for 6 weeks and received injections of saline, NVEs, NVE-KDs, DVEs or DVE-KDs every other day. Atherosclerotic plaque formation was measured using Oil Red Oil staining. RESULTS: Exposure of human umbilical vein and coronary artery endothelial cells to DVEs, but not NVEs, NVE-KDs, or DVE-KDs promoted increased intercellular adhesion molecule-1 expression and monocyte adhesion. DVEs but not NVEs, NVE-KDs, or DVE-KDs also promoted pro-inflammatory polarization of human monocytes in a miR-221/222 dependent manner. Finally, intravenous administration of DVEs, but not NVEs, resulted in a significant increase in atherosclerotic plaque development. CONCLUSION: These data identify a novel paracrine signaling pathway that promotes the cardiovascular complications of diabetes mellitus.
Subject(s)
Atherosclerosis , Diabetes Mellitus, Type 2 , Exosomes , MicroRNAs , Plaque, Atherosclerotic , Humans , Animals , Mice , Muscle, Smooth, Vascular/metabolism , Endothelial Cells/metabolism , Diabetes Mellitus, Type 2/genetics , Diabetes Mellitus, Type 2/metabolism , Exosomes/metabolism , Atherosclerosis/metabolism , MicroRNAs/genetics , MicroRNAs/metabolism , Mice, Inbred C57BL , Myocytes, Smooth Muscle/metabolismABSTRACT
In order to understand how close current layered implosions in indirect-drive inertial confinement fusion are to ignition, it is necessary to measure the level of alpha heating present. To this end, pairs of experiments were performed that consisted of a low-yield tritium-hydrogen-deuterium (THD) layered implosion and a high-yield deuterium-tritium (DT) layered implosion to validate experimentally current simulation-based methods of determining yield amplification. The THD capsules were designed to reduce simultaneously DT neutron yield (alpha heating) and maintain hydrodynamic similarity with the higher yield DT capsules. The ratio of the yields measured in these experiments then allowed the alpha heating level of the DT layered implosions to be determined. The level of alpha heating inferred is consistent with fits to simulations expressed in terms of experimentally measurable quantities and enables us to infer the level of alpha heating in recent high-performing implosions.
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Atherosclerotic plaque rupture is the etiology of ischemic stroke and myocardial infarction. The molecular mechanisms responsible for rupture remain unclear, in part, due to the lack of data from plaques at the time of rupture. Ribosome-depleted total RNA was sequenced from carotid plaques obtained from patients undergoing carotid endarterectomy with high-grade stenosis and either (1) a carotid-related ischemic cerebrovascular event within the previous 5 days ('recently ruptured,' n = 6) or (2) an absence of a cerebrovascular event ('asymptomatic,' n = 5). Principal component analysis confirmed plaque rupture was responsible for the greatest percentage of the variability between samples (23.2%), and recently ruptured plaques were enriched for transcripts associated with inflammation and extracellular matrix degradation. Hierarchical clustering achieved differentiation of the asymptomatic from the recently ruptured plaques. This analysis also found co-expression of transcripts for immunoglobulins and B lymphocyte function, matrix metalloproteinases, and interferon response genes. Examination of the differentially expressed genes supported the importance of inflammation and inhibition of proliferation and migration coupled with an increase in apoptosis. Thus, the transcriptome of recently ruptured plaques is enriched with transcripts associated with inflammation and fibrous cap thinning and support further examination of the role of B lymphocytes and interferons in atherosclerotic plaque rupture.
Subject(s)
Carotid Stenosis , Endarterectomy, Carotid , Plaque, Atherosclerotic , Stroke , Carotid Stenosis/complications , Carotid Stenosis/genetics , Endarterectomy, Carotid/adverse effects , Fibrosis , Humans , Inflammation/complications , Inflammation/genetics , Plaque, Atherosclerotic/complications , Plaque, Atherosclerotic/genetics , Stroke/complications , TranscriptomeABSTRACT
We have previously shown that the probiotic Bifidobacterium breve strain Bif195 alleviates mucosal injury including ulcer formation in the upper intestine induced by non-steroid anti-inflammatory drugs (NSAIDs). Here, we report additional safety use of Bif195 in 126 healthy humans undergoing an exercise-induced intestinal permeability challenge in a double-blinded, placebo-controlled randomised 6-week intervention trial. Intestinal permeability was assessed by urinary lactulose/rhamnose (L/R) ratio. L/R ratio, plasma intestinal fatty acid binding protein (I-FABP) and gastrointestinal symptom rating scale (GSRS) questionnaire were measured resting and after a 1 h treadmill challenge, prior to and at the end of the intervention. To be able to compare the equivalence of resting state at baseline, of this cohort of well-trained subjects, to non-trained subjects, a cohort of 63 healthy and non-trained subjects (<2 h/week of endurance sports) was included. Study subjects (well-trained) were 35.7% women with a mean age and body mass index (in kg/m2) of 35.0 years and 24.8, respectively. There were no differences between the Bif195 and placebo groups in effects on L/R ratio, I-FABP and GSRS questionnaire score. In addition, there were no differences between Bif195 and placebo in number of adverse events and change in cytokines, liver or kidney biomarkers. The exercise model successfully induced intestinal permeability by statistically significantly increasing L/R ratio by ~100% (P<0.0001) and cytokines after the exercise challenge. No significant difference was found between well-trained and non-trained subjects in baseline resting L/R ratio. In conclusion, the reported cytoprotective effects of Bif195 are unlikely to be primarily related to small bowel permeability, and the safety of Bif195 in individuals with increased permeability is supported by the present data. ClinicalTrials.gov: NCT03027583.
Subject(s)
Bifidobacterium breve , Probiotics , Adult , Cytokines , Double-Blind Method , Female , Humans , Intestines , Lactulose , Male , PermeabilityABSTRACT
How quasars powered by supermassive black holes formed less than a billion years after the Big Bang is still one of the outstanding problems in astrophysics, 20 years after their discovery1-4. Cosmological simulations suggest that rare cold flows converging on primordial haloes in low-shear environments could have created these quasars if they were 104-105 solar masses at birth, but could not resolve their formation5-8. Semi-analytical studies of the progenitor halo of a primordial quasar found that it favours the formation of such seeds, but could not verify if one actually appeared9. Here we show that a halo at the rare convergence of strong, cold accretion flows creates massive black holes seeds without the need for ultraviolet backgrounds, supersonic streaming motions or even atomic cooling. Cold flows drive violent, supersonic turbulence in the halo, which prevents star formation until it reaches a mass that triggers sudden, catastrophic baryon collapse that forms 31,000 and 40,000 solar-mass stars. This simple, robust process ensures that haloes capable of forming quasars by a redshift of z > 6 produce massive seeds. The first quasars were thus a natural consequence of structure formation in cold dark matter cosmologies, and not exotic, finely tuned environments as previously thought10-14.
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We present a new solar irradiance reference spectrum representative of solar minimum conditions between solar cycles 24 and 25. The Total and Spectral Solar Irradiance Sensor-1 (TSIS-1) Hybrid Solar Reference Spectrum (HSRS) is developed by applying a modified spectral ratio method to normalize very high spectral resolution solar line data to the absolute irradiance scale of the TSIS-1 Spectral Irradiance Monitor (SIM) and the CubeSat Compact SIM (CSIM). The high spectral resolution solar line data are the Air Force Geophysical Laboratory ultraviolet solar irradiance balloon observations, the ground-based Quality Assurance of Spectral Ultraviolet Measurements In Europe Fourier transform spectrometer solar irradiance observations, the Kitt Peak National Observatory solar transmittance atlas, and the semi-empirical Solar Pseudo-Transmittance Spectrum atlas. The TSIS-1 HSRS spans 202-2730 nm at 0.01 to â¼0.001 nm spectral resolution with uncertainties of 0.3% between 460 and 2365 nm and 1.3% at wavelengths outside that range.
Subject(s)
Education, Pharmacy , Students, Pharmacy , Humans , Pandemics , Patient Care , Pharmacists , Professional RoleABSTRACT
In the San Francisco Bay Area (SFBA), trans women of color are disproportionately affected by HIV and have poor HIV care outcomes. The Brandy Martell Project and TransAccess were two demonstration projects aimed at increasing HIV care engagement and retention among trans women of color in the SFBA. Both projects took place in clinics with a long history of providing trans health care and social services. Both also relied on peer navigation to address systems barriers and promote HIV care linkage and engagement. Our analysis was to identify associations between intervention exposure and primary HIV care visits, ART prescription, and retention in HIV care. Using GEE, we estimated the association between intervention exposure measures (receipt of intervention, intervention dose, intervention provider, and peer dose) and any primary HIV care visit or ART prescription over the 12-month period. Overall, the Brandy Martell Project and TransAccess interventions had significantly positive associations with HIV care outcomes measured. Peer navigation also had a significantly positive association with HIV care outcomes. These interventions demonstrate promise for engaging and retaining trans women of color in HIV care, and call for future investment in this highly underserved community.
Subject(s)
HIV Infections , Skin Pigmentation , Delivery of Health Care , Female , Gender Identity , HIV Infections/prevention & control , Humans , San FranciscoABSTRACT
Insulin-like growth factor-1 (IGF-1) decreases atherosclerosis in apolipoprotein E (Apoe)-deficient mice when administered systemically. However, mechanisms for its atheroprotective effect are not fully understood. We generated endothelium-specific IGF-1 receptor (IGF1R)-deficient mice on an Apoe-deficient background to assess effects of IGF-1 on the endothelium in the context of hyperlipidemia-induced atherosclerosis. Endothelial deficiency of IGF1R promoted atherosclerotic burden, when animals were fed on a high-fat diet for 12 wk or normal chow for 12 mo. Under the normal chow feeding condition, the vascular relaxation response to acetylcholine was increased in the endothelial IGF1R-deficient aorta; however, feeding of a high-fat diet substantially attenuated the relaxation response, and there was no difference between endothelial IGF1R-deficient and control mice. The endothelium and its intercellular junctions provide a barrier function to the vasculature. In human aortic endothelial cells, IGF-1 upregulated occludin, claudin 5, VE-cadherin, JAM-A, and CD31 expression levels, and vice versa, specific IGF1R inhibitor, picropodophyllin, an IGF1R-neutralizing antibody (αIR3), or siRNA to IGF1R abolished the IGF-1 effects on junction and adherens proteins, suggesting that IGF-1 promoted endothelial barrier function. Moreover, endothelial transwell permeability assays indicated that inhibition of IGF-1 signaling elevated solute permeability through the monolayer of human aortic endothelial cells. In summary, endothelial IGF1R deficiency increases atherosclerosis, and IGF-1 positively regulates tight junction protein and adherens junction protein levels and endothelial barrier function. Our findings suggest that the elevation of the endothelial junction protein level is, at least in part, the mechanism for antiatherogenic effects of IGF-1.NEW & NOTEWORTHY Endothelial insulin-like growth factor-1 (IGF-1) receptor deficiency significantly elevated atherosclerotic burden in apolipoprotein E-deficient mice, mediated at least in part by downregulation of intercellular junction proteins and, thus, elevated endothelial permeability. This study revealed a novel role for IGF-1 in supporting endothelial barrier function. These findings suggest that IGF-1's ability to promote endothelial barrier function may offer a novel therapeutic strategy for vascular diseases such as atherosclerosis.
Subject(s)
Aortic Diseases/metabolism , Atherosclerosis/metabolism , Capillary Permeability , Endothelial Cells/metabolism , Receptor, IGF Type 1/deficiency , Animals , Antigens, CD/metabolism , Aortic Diseases/genetics , Aortic Diseases/pathology , Atherosclerosis/genetics , Atherosclerosis/pathology , Cadherins/metabolism , Disease Models, Animal , Disease Progression , Endothelial Cells/pathology , Humans , Mice, Inbred C57BL , Mice, Knockout, ApoE , Plaque, Atherosclerotic , Platelet Endothelial Cell Adhesion Molecule-1/metabolism , Receptor, IGF Type 1/genetics , Receptor, IGF Type 1/metabolism , THP-1 Cells , Tight Junction Proteins/metabolism , Tight Junctions/metabolismABSTRACT
Renal proximal tubular angiotensinogen (AGT) is increased by hyperglycemia (HG) in diabetes mellitus, which augments intrarenal angiotensin II formation, contributing to the development of hypertension and kidney injury. Sodium-glucose cotransporter 2 (SGLT2) is abundantly expressed in proximal tubular cells (PTCs). The present study investigated the effects of canagliflozin (CANA), a SGLT2 inhibitor, on HG-induced AGT elevation in cultured PTCs. Mouse PTCs were treated with 5-25 mM glucose. CANA (0-10 µM) was applied 1 h before glucose treatment. Glucose (10 mM) increased AGT mRNA and protein levels at 12 h (3.06 ± 0.48-fold in protein), and 1 and 10 µM CANA as well as SGLT2 shRNA attenuated the AGT augmentation. CANA did not suppress the elevated AGT levels induced by 25 mM glucose. Increased AGT expression induced by treatment with pyruvate, a glucose metabolite that does not require SGLT2 for uptake, was not attenuated by CANA. In HG-treated PTCs, intracellular reactive oxygen species levels were elevated compared with baseline (4.24 ± 0.23-fold), and these were also inhibited by CANA. Furthermore, tempol, an antioxidant, attenuated AGT upregulation in HG-treated PTCs. HG-induced AGT upregulation was not inhibited by an angiotensin II receptor antagonist, indicating that HG stimulates AGT expression in an angiotensin II-independent manner. These results indicate that enhanced glucose entry via SGLT2 into PTCs elevates intracellular reactive oxygen species generation by stimulation of glycolysis and consequent AGT augmentation. SGLT2 blockade limits HG-induced AGT stimulation, thus reducing the development of kidney injury in diabetes mellitus.
Subject(s)
Angiotensinogen/metabolism , Canagliflozin/pharmacology , Glucose/pharmacology , Kidney Tubules, Proximal/drug effects , Sodium-Glucose Transporter 2 Inhibitors/pharmacology , Sodium-Glucose Transporter 2/metabolism , Animals , Cell Line , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Kidney Tubules, Proximal/metabolism , Male , Mice , Reactive Oxygen Species/metabolism , Renin-Angiotensin System/drug effectsABSTRACT
INTRODUCTION: Despite the potential of social media to influence public health and generate insights, the process of monitoring and analyzing the dissemination of health care messages on social media has been described as difficult and in need of improvement. OBJECTIVES: The objective of this study was to describe and demonstrate a reproducible methodology for cataloging and analyzing health care-related social media comments and provide insight into how clinicians and members of the general public respond to health care messaging on social media. METHODS: We collected social media comments related to the American Dental Association's 2016 "Evidence-Based Clinical Practice Guideline for the Use of Pit-and-Fissure Sealants" between April 10, 2017, and October 31, 2017, from Facebook, Twitter, LinkedIn, Reddit, and online message boards for the New York Times, FiveThirtyEight, and Dentaltown. Using data provided in the comments, we conducted engagement analysis as well as content, network, and sentiment analysis across 8 categories. RESULTS: We collected 671 comments. Among our findings, Facebook (472 of 671) was the most popular platform among commentators; almost half of all comments (335 of 671) aligned with the recommendations of the 2016 American Dental Association sealants guideline; clinicians were more likely than the general public to like a comment that suggested an improvement to the guideline; and >75% of comments (521 of 671) were supported by anecdotal evidence. CONCLUSION: As the prevalence of anecdotes on social media suggests, the likelihood of falsehoods spreading on social media is high. Insights gleaned from the methodology described in this research could help combat the spread of such misinformation by providing disseminators of health care messaging with insight into their target audiences. Armed with this knowledge, disseminators can craft health care messages that more effectively engage clinicians and the general public. KNOWLEDGE TRANSFER STATEMENT: The methodology used in this research provides a reproducible strategy for tracking social media engagement with health care messages. Engagement results can assist future delivery of health care messages to key stakeholders and ensure better implementation and adoption of these communications.
Subject(s)
Social Media , Delivery of Health Care , New York , Public Health , Research Design , United StatesABSTRACT
Aim: To determine if porcine urinary bladder matrix (UBM) treatment is associated with modulation of wound inflammation in diabetic patients. Patients & methods: mRNA associated with M1 and M2 macrophages were measured in wounds of diabetic and nondiabetic patients pre- and post-treatment with UBM and an M1:M2 score was calculated. Results: Wound tissue from diabetic subjects exhibited elevated M1:M2 scores compared with nondiabetic patients, suggesting a greater pro-inflammatory state prior to treatment. Post-treatment, there was significantly greater reduction in the magnitude of the individual M1:M2 scores in the diabetic patients resulting in similar levels in both groups of patients. Conclusions: UBM may assist in diabetic wound healing by restoring an inflammatory state similar to that of nondiabetic patients.
Subject(s)
Extracellular Matrix/metabolism , Inflammation/pathology , Urinary Bladder/anatomy & histology , Wound Healing , Adult , Animals , Female , Gene Expression Regulation , Humans , Macrophages/metabolism , Macrophages/pathology , Male , Middle Aged , Phenotype , RNA, Messenger/genetics , RNA, Messenger/metabolism , Swine , Young AdultABSTRACT
BACKGROUND: Hypertension and renal injury are common complications of type 2 diabetes mellitus (T2DM). Hyperglycemia stimulates renal proximal tubular angiotensinogen (AGT) expression via elevated oxidative stress contributing to the development of high blood pressure and diabetic nephropathy. The sodium glucose cotransporter 2 (SGLT2) in proximal tubules is responsible for the majority of glucose reabsorption by renal tubules. We tested the hypothesis that SGLT2 inhibition with canagliflozin (CANA) prevents intrarenal AGT augmentation and ameliorates kidney injury and hypertension in T2DM. METHODS: We induced T2DM in New Zealand obese mice with a high fat diet (DM, 30% fat) with control mice receiving regular fat diet (ND, 4% fat). When DM mice exhibited > 350 mg/dL blood glucose levels, both DM- and ND-fed mice were treated with 10 mg/kg/day CANA or vehicle by oral gavage for 6 weeks. We evaluated intrarenal AGT, blood pressure, and the development of kidney injury. RESULTS: Systolic blood pressure in DM mice (133.9 ± 2.0 mm Hg) was normalized by CANA (113.9 ± 4.0 mm Hg). CANA treatment ameliorated hyperglycemia-associated augmentation of renal AGT mRNA (148 ± 21 copies/ng RNA in DM, and 90 ± 16 copies/ng RNA in DM + CANA) and protein levels as well as elevation of urinary 8-isoprostane levels. Tubular fibrosis in DM mice (3.4 ± 0.9-fold, fibrotic score, ratio to ND) was suppressed by CANA (0.9 ± 0.3-fold). Furthermore, CANA attenuated DM associated increased macrophage infiltration and cell proliferation in kidneys of DM mice. CONCLUSIONS: CANA prevents intrarenal AGT upregulation and oxidative stress and which may mitigate high blood pressure, renal tubular fibrosis, and renal inflammation in T2DM.
Subject(s)
Angiotensinogen/metabolism , Canagliflozin/administration & dosage , Diabetes Mellitus, Type 2/drug therapy , Diabetic Nephropathies/prevention & control , Hypertension/prevention & control , Sodium-Glucose Transporter 2 Inhibitors/administration & dosage , Animals , Blood Glucose/analysis , Blood Glucose/drug effects , Blood Pressure/drug effects , Diabetes Mellitus, Experimental/blood , Diabetes Mellitus, Experimental/complications , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/complications , Diabetic Nephropathies/etiology , Diabetic Nephropathies/pathology , Diet, High-Fat/adverse effects , Fibrosis , Humans , Hypertension/etiology , Hypertension/pathology , Kidney Tubules, Proximal/drug effects , Kidney Tubules, Proximal/immunology , Kidney Tubules, Proximal/pathology , Mice , Oxidative Stress/drug effects , Oxidative Stress/immunology , Up-Regulation/drug effectsABSTRACT
Achieving a symmetric implosion in National Ignition Facility indirect drive targets requires understanding and control of dynamic changes to the laser power transport in the hohlraum. We developed a new experimental platform to simultaneously visualize wall-plasma motion and dynamic laser power transport in the hohlraum and are using it to investigate correlations of these measurements with the imploded capsule symmetry. In a series of experiments where we made one single parameter variation, we show the value of this new platform in developing an understanding of laser transport and implosion symmetry. This platform also provides a new way to evaluate dynamic performance of advanced hohlraum designs.
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To reach the pressures and densities required for ignition, it may be necessary to develop an approach to design that makes it easier for simulations to guide experiments. Here, we report on a new short-pulse inertial confinement fusion platform that is specifically designed to be more predictable. The platform has demonstrated 99%+0.5% laser coupling into the hohlraum, high implosion velocity (411 km/s), high hotspot pressure (220+60 Gbar), and high cold fuel areal density compression ratio (>400), while maintaining controlled implosion symmetry, providing a promising new physics platform to study ignition physics.
ABSTRACT
Objective- IGF-1 (insulin-like growth factor 1) is a major autocrine/paracrine growth factor, which promotes cell proliferation, migration, and survival. We have shown previously that IGF-1 reduced atherosclerosis and promoted features of stable atherosclerotic plaque in Apoe-/- mice-an animal model of atherosclerosis. The aim of this study was to assess effects of smooth muscle cell (SMC) IGF-1 signaling on the atherosclerotic plaque. Approach and Results- We generated Apoe-/- mice with IGF1R (IGF-1 receptor) deficiency in SMC and fibroblasts (SM22α [smooth muscle protein 22 α]-CreKI/IGF1R-flox mice). IGF1R was decreased in the aorta and adventitia of SM22α-CreKI/IGF1R-flox mice and also in aortic SMC, embryonic, skin, and lung fibroblasts isolated from SM22α-CreKI/IGF1R-flox mice. IGF1R deficiency downregulated collagen mRNA-binding protein LARP6 (La ribonucleoprotein domain family, member 6) and vascular collagen, and mice exhibited growth retardation. The high-fat diet-fed SM22α-CreKI/IGF1R-flox mice had increased atherosclerotic burden and inflammatory responses. α-SMA (α-smooth muscle actin)-positive plaque cells had reduced proliferation and elevated apoptosis. SMC/fibroblast-targeted decline in IGF-1 signaling decreased atherosclerotic plaque SMC, markedly depleted collagen, reduced plaque fibrous cap, and increased plaque necrotic cores. Aortic SMC isolated from SM22α-CreKI/IGF1R-flox mice had decreased cell proliferation, migration, increased sensitivity to apoptosis, and these effects were associated with disruption of IGF-1-induced Akt signaling. Conclusions- IGF-1 signaling in SMC and in fibroblast is a critical determinant of normal vascular wall development and atheroprotection.
Subject(s)
Aortic Diseases/metabolism , Atherosclerosis/metabolism , Microfilament Proteins/genetics , Muscle Proteins/genetics , Muscle, Smooth, Vascular/metabolism , Myocytes, Smooth Muscle/metabolism , Plaque, Atherosclerotic , Promoter Regions, Genetic , Receptor, IGF Type 1/deficiency , Actins/metabolism , Animals , Aorta/metabolism , Aorta/pathology , Aortic Diseases/genetics , Aortic Diseases/pathology , Apoptosis , Atherosclerosis/genetics , Atherosclerosis/pathology , Autoantigens/metabolism , Cell Movement , Cell Proliferation , Cells, Cultured , Collagen/metabolism , Disease Models, Animal , Female , Fibroblasts/metabolism , Fibrosis , Male , Mice, Inbred C57BL , Mice, Knockout, ApoE , Muscle, Smooth, Vascular/pathology , Myocytes, Smooth Muscle/pathology , Proto-Oncogene Proteins c-akt/metabolism , Receptor, IGF Type 1/genetics , Ribonucleoproteins/metabolism , Signal Transduction , SS-B AntigenABSTRACT
Transwomen of color are disproportionately impacted by HIV and may have worse health outcomes than other populations. This analysis was conducted to examine structural factors associated with poor health outcomes among transwomen of color living with HIV in the San Francisco Bay Area (N = 159). Univariate and multivariable analyses were conducted to determine if structural factors were associated with poor HIV-related health outcomes. A majority of participants were Black or African American (110/159, 69.2%), 32 (20.1%) identified their primary race/ethnicity as Hispanic or Latino/a or Spanish, and 17 (10.7%) identified as another race/ethnicity. Transwomen of color in our sample faced extreme structural barriers, including residential transience, extreme low income, high prevalence of running out of money in the last six months, high rates of food insecurity, high prevalence of income via entitlement programs, engagement in sex work and other illicit activities for income. Unstable housing was the structural factor most consistently associated with poor health outcomes along the HIV care continuum and may explain engagement in other sources of income generation. Interventions are needed that go beyond the individual and health care-level to address needs for housing and economic opportunities to improve HIV care outcomes among transwomen of color living with HIV in the San Francisco Bay Area.