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3.
Psychoneuroendocrinology ; 161: 106946, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38198904

RESUMEN

BACKGROUND: The relationship between insulin-like growth factor-1 (IGF-1) and cognition has been studied in healthy individuals, but not extensively with regards to insulin resistance and type 2 diabetes mellitus (T2DM). In this retrospective observational study, we investigated relationships of IGF-1 with memory and executive function across people with normoglycemia, prediabetes, and T2DM. METHODS: Data from the Midlife in the United States (MIDUS) study were used. Episodic memory and executive function were assessed using the Brief Test of Adult Cognition by Telephone approximately 21.42 ± 12.10 months prior to measuring IGF-1 levels from a fasting blood sample. Normoglycemia was identified as individuals without a physician diagnosis of diabetes and glycated hemoglobin (HbA1c) ≤5.6%. Prediabetes was identified as those without a physician diagnosis of diabetes and HbA1c between 5.7%-6.4%. T2DM was identified as anyone with a physician diagnosis of diabetes, or HbA1c ≥6.5%, or anyone using an oral hypoglycemic medication. The associations were assessed using linear regressions controlling for age, sex, education, body mass index, C-reactive protein, HbA1c or homeostatic model of insulin resistance, MIDUS wave, exercise, smoking status, sleep quality, alcohol intake, oral hypoglycemic use, and insulin use. RESULTS: The study included 1400 participants, which consisted of 583 normoglycemic (48.4% female, mean age 51.0 ± 12.2 years), 512 prediabetes (58.4% female, mean age 57.3 ± 11.8 years), and 305 T2DM participants (53.8% female, mean age 57.6 ± 11.5 years). Peripheral IGF-1 concentrations were lower (F2,1397 = 28.29, p < 0.001) in people with prediabetes or T2DM, vs. normoglycemia. Participants with prediabetes or T2DM had lower episodic memory (F2,1397 = 9.21, p < 0.001) and executive function (F2,1397 = 20.29, p < 0.001) composite z-scores than people with normoglycemia. Higher IGF-1 concentrations were associated with better executive performance in individuals with prediabetes (ß = 0.115 [0.028, 0.202], p = 0.010), but not in individuals with normoglycemia or T2DM. An interaction between IGF-1 and sex in predicting executive function was observed in the prediabetes group (ß = -0.344, p = 0.042), where the relationship was weaker in females (ß = 0.106 [-0.012, 0.224], p = 0.077) than males (ß = 0.251 [0.123, 0.380], p < 0.001). No associations were seen between IGF-1 and memory. CONCLUSION: The results suggest that peripheral IGF-1 concentrations may be related to executive function, and that the relationship may be sex-specific and dependent on diabetes status.


Asunto(s)
Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Estado Prediabético , Masculino , Adulto , Humanos , Femenino , Persona de Mediana Edad , Anciano , Diabetes Mellitus Tipo 2/complicaciones , Estado Prediabético/complicaciones , Hemoglobina Glucada , Péptidos Similares a la Insulina , Factor I del Crecimiento Similar a la Insulina , Glucemia/metabolismo , Hipoglucemiantes/uso terapéutico , Cognición
4.
Lancet Microbe ; 5(3): e216-e225, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38278167

RESUMEN

BACKGROUND: Accurate quantitation of immune markers is crucial for ensuring reliable assessment of vaccine efficacy against infectious diseases. This study was designed to confirm standardised performance of SARS-CoV-2 assays used to evaluate COVID-19 vaccine candidates at the initial seven laboratories (in North America, Europe, and Asia) of the Coalition for Epidemic Preparedness Innovations (CEPI) Centralized Laboratory Network (CLN). METHODS: Three ELISAs (pre-spike protein, receptor binding domain, and nucleocapsid), a microneutralisation assay (MNA), a pseudotyped virus-based neutralisation assay (PNA), and an IFN-γ T-cell ELISpot assay were developed, validated or qualified, and transferred to participating laboratories. Immune responses were measured in ELISA laboratory units (ELU) for ELISA, 50% neuralisation dilution (ND50) for MNA, 50% neutralisation titre (NT50) for PNA, and spot-forming units for the ELISpot assay. Replicate assay results of well characterised panels and controls of blood samples from individuals with or without SARS-CoV-2 infection were evaluated by geometric mean ratios, standard deviation, linear regression, and Spearman correlation analysis for consistency, accuracy, and linearity of quantitative measurements across all laboratories. FINDINGS: High reproducibility of results across all laboratories was demonstrated, with interlaboratory precision of 4·1-7·7% coefficient of variation for all three ELISAs, 3·8-19·5% for PNA, and 17·1-24·1% for MNA, over a linear range of 11-30 760 ELU per mL for the three ELISAs, 14-7876 NT50 per mL for PNA, and 21-25 587 ND50 per mL for MNA. The MNA was also adapted for detection of neutralising antibodies against the major SARS-CoV-2 variants of concern. The results of PNA and MNA (r=0·864) and of ELISA and PNA (r=0·928) were highly correlated. The IFN-γ ELISpot interlaboratory variability was 15·9-49·9% coefficient of variation. Sensitivity and specificity were close to 100% for all assays. INTERPRETATION: The CEPI CLN provides accurate quantitation of anti-SARS-CoV-2 immune response across laboratories to allow direct comparisons of different vaccine formulations in different geographical areas. Lessons learned from this programme will serve as a model for faster responses to future pandemic threats and roll-out of effective vaccines. FUNDING: CEPI.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/prevención & control , Vacunas contra la COVID-19 , Laboratorios , Reproducibilidad de los Resultados , Anticuerpos Antivirales , Inmunidad
5.
Arterioscler Thromb Vasc Biol ; 44(1): 271-286, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37823267

RESUMEN

BACKGROUND: Prostacyclin is a fundamental signaling pathway traditionally associated with the cardiovascular system and protection against thrombosis but which also has regulatory functions in fibrosis, proliferation, and immunity. Prevailing dogma states that prostacyclin is principally derived from vascular endothelium, although it is known that other cells can also synthesize it. However, the role of nonendothelial sources in prostacyclin production has not been systematically evaluated resulting in an underappreciation of their importance relative to better characterized endothelial sources. METHODS: To address this, we have used novel endothelial cell-specific and fibroblast-specific COX (cyclo-oxygenase) and prostacyclin synthase knockout mice and cells freshly isolated from mouse and human lung tissue. We have assessed prostacyclin release by immunoassay and thrombosis in vivo using an FeCl3-induced carotid artery injury model. RESULTS: We found that in arteries, endothelial cells are the main source of prostacyclin but that in the lung, and other tissues, prostacyclin production occurs largely independently of endothelial and vascular smooth muscle cells. Instead, in mouse and human lung, prostacyclin production was strongly associated with fibroblasts. By comparison, microvascular endothelial cells from the lung showed weak prostacyclin synthetic capacity compared with those isolated from large arteries. Prostacyclin derived from fibroblasts and other nonendothelial sources was seen to contribute to antithrombotic protection. CONCLUSIONS: These observations define a new paradigm in prostacyclin biology in which fibroblast/nonendothelial-derived prostacyclin works in parallel with endothelium-derived prostanoids to control thrombotic risk and potentially a broad range of other biology. Although generation of prostacyclin by fibroblasts has been shown previously, the scale and systemic activity was unappreciated. As such, this represents a basic change in our understanding and may provide new insight into how diseases of the lung result in cardiovascular risk.


Asunto(s)
Epoprostenol , Trombosis , Ratones , Humanos , Animales , Fibrinolíticos , Células Endoteliales/metabolismo , Prostaglandinas I/metabolismo , Prostaglandinas I/farmacología , Endotelio Vascular/metabolismo , Ratones Noqueados , Fibroblastos/metabolismo , Trombosis/genética , Trombosis/prevención & control , Trombosis/metabolismo
6.
Eur Respir J ; 63(2)2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38123239

RESUMEN

BACKGROUND: Short-term studies suggest that dietary nitrate (NO3 -) supplementation may improve the cardiovascular risk profile, lowering blood pressure (BP) and enhancing endothelial function. It is not clear if these beneficial effects are sustained and whether they apply in people with COPD, who have a worse cardiovascular profile than those without COPD. Nitrate-rich beetroot juice (NR-BRJ) is a convenient dietary source of nitrate. METHODS: The ON-BC trial was a randomised, double-blind, placebo-controlled parallel group study in stable COPD patients with home systolic BP (SBP) measurement ≥130 mmHg. Participants were randomly allocated (1:1) using computer-generated, block randomisation to either 70 mL NR-BRJ (400 mg NO3 -) (n=40) or an otherwise identical nitrate-depleted placebo juice (0 mg NO3 -) (n=41), once daily for 12 weeks. The primary end-point was between-group change in home SBP measurement. Secondary outcomes included change in 6-min walk distance (6MWD) and measures of endothelial function (reactive hyperaemia index (RHI) and augmentation index normalised to a heart rate of 75 beats·min-1 (AIx75)) using an EndoPAT device. Plasma nitrate and platelet function were also measured. RESULTS: Compared with placebo, active treatment lowered SBP (Hodges-Lehmann treatment effect -4.5 (95% CI -5.9- -3.0) mmHg), and improved 6MWD (30.0 (95% CI 15.7-44.2) m; p<0.001), RHI (0.34 (95% CI 0.03-0.63); p=0.03) and AIx75 (-7.61% (95% CI -14.3- -0.95%); p=0.026). CONCLUSIONS: In people with COPD, prolonged dietary nitrate supplementation in the form of beetroot juice produces a sustained reduction in BP, associated with an improvement in endothelial function and exercise capacity.


Asunto(s)
Enfermedades Cardiovasculares , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Nitratos/uso terapéutico , Enfermedades Cardiovasculares/prevención & control , Enfermedades Cardiovasculares/tratamiento farmacológico , Suplementos Dietéticos , Factores de Riesgo , Presión Sanguínea , Antioxidantes , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Método Doble Ciego , Estudios Cruzados
7.
Cells ; 12(23)2023 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-38067192

RESUMEN

(1) Pulmonary hypertension (PH)-associated right ventricular (RV) failure is linked to a reduction in pulmonary vasodilators. Treprostinil has shown effectiveness in PAH patients with cardiac decompensation, hinting at potential cardiac benefits. We investigated treprostinil's synergy with isoprenaline in RV and LV cardiomyocytes. We hypothesised that disease-related RV structural changes in cardiomyocytes would reduce contractile responses and cAMP/PKA signalling activity. (2) We induced PH in male Sprague Dawley rats using monocrotaline and isolated their ventricular cardiomyocytes. The effect of in vitro treprostinil and isoprenaline stimulation on contraction was assessed. FRET microscopy was used to study PKA activity associated with treprostinil stimulation in AKAR3-NES FRET-based biosensor-expressing cells. (3) RV cells exhibited maladaptive remodelling with hypertrophy, impaired contractility, and calcium transients compared to control and LV cardiomyocytes. Combining treprostinil and isoprenaline failed to enhance inotropy in PH RV cardiomyocytes. PH RV cardiomyocytes displayed an aberrant contractile behaviour, which the combination treatment could not rectify. Finally, we observed decreased PKA activity in treprostinil-treated PH RV cardiomyocytes. (4) PH-associated RV cardiomyocyte remodelling reduced treprostinil sensitivity, inotropic support, and impaired relaxation. Overall, this study highlights the complexity of RV dysfunction in advanced PH and suggests the need for alternative therapeutic strategies.


Asunto(s)
Insuficiencia Cardíaca , Hipertensión Pulmonar , Humanos , Ratas , Animales , Masculino , Miocitos Cardíacos , Isoproterenol/farmacología , Ratas Sprague-Dawley
8.
JBMR Plus ; 7(12): e10841, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38130768

RESUMEN

GαS, the stimulatory G protein α-subunit that raises intracellular cAMP levels by activating adenylyl cyclase, plays a vital role in bone development, maintenance, and remodeling. Previously, using transgenic mice overexpressing GαS in osteoblasts (GS-Tg), we demonstrated the influence of osteoblast GαS level on osteogenesis, bone turnover, and skeletal responses to hyperparathyroidism. To further investigate whether alterations in GαS levels affect endochondral bone repair, a postnatal bone regenerative process that recapitulates embryonic bone development, we performed stabilized tibial osteotomy in male GS-Tg mice at 8 weeks of age and examined the progression of fracture healing by micro-CT, histomorphometry, and gene expression analysis over a 4-week period. Bone fractures from GS-Tg mice exhibited diminished cartilage formation at the time of peak soft callus formation at 1 week post-fracture followed by significantly enhanced callus mineralization and new bone formation at 2 weeks post-fracture. The opposing effects on chondrogenesis and osteogenesis were validated by downregulation of chondrogenic markers and upregulation of osteogenic markers. Histomorphometric analysis at times of increased bone formation (2 and 3 weeks post-fracture) revealed excess fibroblast-like cells on newly formed woven bone surfaces and elevated osteocyte density in GS-Tg fractures. Coincident with enhanced callus mineralization and bone formation, GS-Tg mice showed elevated active ß-catenin and Wntless proteins in osteoblasts at 2 weeks post-fracture, further substantiated by increased mRNA encoding various canonical Wnts and Wnt target genes, suggesting elevated osteoblastic Wnt secretion and Wnt/ß-catenin signaling. The GS-Tg bony callus at 4 weeks post-fracture exhibited greater mineral density and decreased polar moment of inertia, resulting in improved material stiffness. These findings highlight that elevated GαS levels increase Wnt signaling, conferring an increased osteogenic differentiation potential at the expense of chondrogenic differentiation, resulting in improved mechanical integrity. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research.

9.
J Clin Invest ; 133(18)2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-37712420

RESUMEN

Idiopathic pulmonary fibrosis (IPF) is a progressive scarring disease of the lung with poor survival. The incidence and mortality of IPF are rising, but treatment remains limited. Currently, two drugs can slow the scarring process but often at the expense of intolerable side effects, and without substantially changing overall survival. A better understanding of mechanisms underlying IPF is likely to lead to improved therapies. The current paradigm proposes that repetitive alveolar epithelial injury from noxious stimuli in a genetically primed individual is followed by abnormal wound healing, including aberrant activity of extracellular matrix-secreting cells, with resultant tissue fibrosis and parenchymal damage. However, this may underplay the importance of the vascular contribution to fibrogenesis. The lungs receive 100% of the cardiac output, and vascular abnormalities in IPF include (a) heterogeneous vessel formation throughout fibrotic lung, including the development of abnormal dilated vessels and anastomoses; (b) abnormal spatially distributed populations of endothelial cells (ECs); (c) dysregulation of endothelial protective pathways such as prostacyclin signaling; and (d) an increased frequency of common vascular and metabolic comorbidities. Here, we propose that vascular and EC abnormalities are both causal and consequential in the pathobiology of IPF and that fuller evaluation of dysregulated pathways may lead to effective therapies and a cure for this devastating disease.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Fibrosis Pulmonar Idiopática , Humanos , Células Endoteliales , Cicatriz , Epoprostenol
10.
Kidney Int Rep ; 8(6): 1231-1238, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37284684

RESUMEN

Introduction: Through the production of prostacyclin, cyclooxygenase (COX)-2 protects the cardiorenal system. Asymmetric dimethylarginine (ADMA), is a biomarker of cardiovascular and renal disease. Here we determined the relationship between COX-2/prostacyclin, ADMA, and renal function in mouse and human models. Methods: We used plasma from COX-2 or prostacyclin synthase knockout mice and from a unique individual lacking COX-derived prostaglandins (PGs) because of a loss of function mutation in cytosolic phospholipase A2 (cPLA2), before and after receiving a cPLA2-replete transplanted donor kidney. ADMA, arginine, and citrulline were measured using ultra-high performance liquid-chromatography tandem mass spectrometry. ADMA and arginine were also measured by enzyme-linked immunosorbent assay (ELISA). Renal function was assessed by measuring cystatin C by ELISA. ADMA and prostacyclin release from organotypic kidney slices were also measured by ELISA. Results: Loss of COX-2 or prostacyclin synthase in mice increased plasma levels of ADMA, citrulline, arginine, and cystatin C. ADMA, citrulline, and arginine positively correlated with cystatin C. Plasma ADMA, citrulline, and cystatin C, but not arginine, were elevated in samples from the patient lacking COX/prostacyclin capacity compared to levels in healthy volunteers. Renal function, ADMA, and citrulline were returned toward normal range when the patient received a genetically normal kidney, capable of COX/prostacyclin activity; and cystatin C positively correlated with ADMA and citrulline. Levels of ADMA and prostacyclin in conditioned media of kidney slices were not altered in tissue from COX-2 knockout mice compared to wildtype controls. Conclusion: In human and mouse models, where renal function is compromised because of loss of COX-2/PGI2 signaling, ADMA levels are increased.

11.
Connect Tissue Res ; 64(4): 350-361, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37046359

RESUMEN

BACKGROUND: ß-Arrestin 2 (ß-arr2) binds activated parathyroid hormone (PTH) receptors stimulating internalization. PTH stimulates both anabolic and catabolic effect on bone depending on the way it is administered. Intermittent PTH stimulation increases trabecular bone formation in mice, but this is decreased in mice lacking ß-arr 2, suggesting a role for ß-arr 2 in the anabolic effects of PTH. The role of ß-arr 2 in the catabolic effects of continuous PTH (cPTH) treatment is not known. OBJECTIVE: To assess the effects of cPTH administration on bone in mice lacking ß-arr 2 compared to wild-type (WT). METHODS: Groups of male and female WT or ß-arr2 knockout (KO) mice were administered either PTH or phosphate-buffered saline by osmotic pumps for 2 weeks. Following treatment, serum calcium and phosphate levels were measured, bone structure and mineral density were measured by microcomputed tomography, and bone cells measured by static and dynamic histomorphometry. RESULTS: ß-arr2 KO had no effects on skeletal development in mice of either sex. PTH treatment caused hypercalcemia and hypophosphatemia and decreased trabecular and cortical bone only in male WT mice. ß-arr2 KO in male mice completely abrogated the effects of PTH on bone, while in female ß-arr2 KO mice, PTH treatment increased trabecular bone with no effects on cortical bone. CONCLUSIONS: These results demonstrate a profound sex effect on skeletal responses to cPTH treatment, suggesting a protective effect of estrogen on bone loss. ß-arr2 plays a role in restraining the anabolic effects of PTH in both male and female mice.


Asunto(s)
Anabolizantes , Hormona Paratiroidea , Masculino , Femenino , Animales , Ratones , Hormona Paratiroidea/farmacología , Hormona Paratiroidea/metabolismo , Arrestina beta 2/metabolismo , Arrestina beta 2/farmacología , Anabolizantes/farmacología , Microtomografía por Rayos X , Densidad Ósea , Fosfatos/farmacología , Ratones Noqueados
12.
ERJ Open Res ; 9(2)2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36949962

RESUMEN

Background: Nintedanib slows lung function decline for patients with non-idiopathic pulmonary fibrosis progressive pulmonary fibrosis (PPF) in clinical trials, but the real-world safety and efficacy are not known. Methods: In this retrospective cohort study, standardised data were collected from patients in whom nintedanib was initiated for PPF between 2019 and 2020 through an early-access programme across eight centres in the United Kingdom. Rate of lung function change in the 12 months pre- and post-nintedanib initiation was the primary analysis. Symptoms, drug safety, tolerability and stratification by interstitial lung disease subtype and computed tomography pattern were secondary analyses. Results: 126 patients were included; 67 (53%) females; mean±sd age 60±13 years. At initiation of nintedanib, mean forced vital capacity (FVC) was 1.87 L (58% predicted) and diffusing capacity of the lung for carbon monoxide (D LCO) was 32.7% predicted. 68% of patients were prescribed prednisolone (median dose 10 mg) and 69% were prescribed a steroid-sparing agent. In the 12 months after nintedanib initiation, lung function decline was significantly lower than in the preceding 12 months: FVC -88.8 mL versus -239.9 mL (p=0.004), and absolute decline in D LCO -2.1% versus -6.1% (p=0.004). Response to nintedanib was consistent in sensitivity and secondary analyses. 89 (71%) out of 126 patients reported side-effects, but 86 (80%) of the surviving 108 patients were still taking nintedanib at 12 months with patients reporting a reduced perception of symptom decline. There were no serious adverse events. Conclusion: In PPF, the real-world efficacy of nintedanib replicated that of clinical trials, significantly attenuating lung function decline. Despite the severity of disease, nintedanib was safe and well tolerated in this real-world multicentre study.

13.
Sci Transl Med ; 14(671): eabo5795, 2022 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-36383686

RESUMEN

Interstitial lung disease and associated fibrosis occur in a proportion of individuals who have recovered from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection through unknown mechanisms. We studied individuals with severe coronavirus disease 2019 (COVID-19) after recovery from acute illness. Individuals with evidence of interstitial lung changes at 3 to 6 months after recovery had an up-regulated neutrophil-associated immune signature including increased chemokines, proteases, and markers of neutrophil extracellular traps that were detectable in the blood. Similar pathways were enriched in the upper airway with a concomitant increase in antiviral type I interferon signaling. Interaction analysis of the peripheral phosphoproteome identified enriched kinases critical for neutrophil inflammatory pathways. Evaluation of these individuals at 12 months after recovery indicated that a subset of the individuals had not yet achieved full normalization of radiological and functional changes. These data provide insight into mechanisms driving development of pulmonary sequelae during and after COVID-19 and provide a rational basis for development of targeted approaches to prevent long-term complications.


Asunto(s)
COVID-19 , Trampas Extracelulares , Humanos , SARS-CoV-2 , Neutrófilos , Pulmón
14.
Blood Adv ; 6(23): 6028-6038, 2022 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-36037520

RESUMEN

The proportion of young platelets, also known as newly formed or reticulated, within the overall platelet population has been clinically correlated with adverse cardiovascular outcomes. However, our understanding of this is incomplete because of limitations in the technical approaches available to study platelets of different ages. In this study, we have developed and validated an in vivo temporal labeling approach using injectable fluorescent antiplatelet antibodies to subdivide platelets by age and assess differences in functional and molecular characteristics. With this approach, we found that young platelets (<24 hours old) in comparison with older platelets respond to stimuli with greater calcium flux and degranulation and contribute more to the formation of thrombi in vitro and in vivo. Sequential sampling confirmed this altered functionality to be independent of platelet size, with distribution of sizes of tracked platelets commensurate with the global platelet population throughout their 5-day lifespan in the circulation. The age-associated decrease in thrombotic function was accompanied by significant decreases in the surface expression of GPVI and CD31 (PECAM-1) and an increase in CD9. Platelet messenger RNA (mRNA) content also decreased with age but at different rates for individual mRNAs indicating apparent conservation of those encoding granule proteins. Our pulse-chase-type approach to define circulating platelet age has allowed timely reexamination of commonly held beliefs regarding size and reactivity of young platelets while providing novel insights into the temporal regulation of receptor and protein expression. Overall, future application of this validated tool will inform age-based platelet heterogeneity in physiology and disease.


Asunto(s)
Plaquetas , Trombosis , Ratones , Animales , Plaquetas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptor para Productos Finales de Glicación Avanzada/metabolismo , Gránulos Citoplasmáticos , Expresión Génica , Trombosis/metabolismo
15.
J Endocrinol ; 254(1): 13-26, 2022 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-35638565

RESUMEN

GS, the stimulatory heterotrimeric G protein, is an essential regulator of osteogenesis and bone turnover. To determine if increasing GαS in osteoblasts alters bone responses to hyperparathyroidism, we used a transgenic mouse line overexpressing GαS in osteoblasts (GS-Tg mice). Primary osteoblasts from GS-Tg mice showed increased basal and parathyroid hormone (PTH)-stimulated cAMP and greater responses to PTH than cells from WT mice. Skeletal responses to 2-week continuous PTH administration (cPTH) in female mice resulted in trabecular bone loss in WT mice but 74% and 34% increase in trabecular bone mass in long bones and vertebrae, respectively, in GS-Tg mice. Vertebral biomechanical strength was compromised by cPTH treatment in WT mice but not in GS-Tg. Increased peritrabecular fibrosis was greatly increased by cPTH in Gs-Tg compared to WT mice and corresponded with greater increases in Wnt pathway proteins in trabecular bone. Cortical bone responded negatively to cPTH in WT and Gs-Tg mice with large increases in porosity, decreased cortical thickness and compromised biomechanical properties. These results demonstrate that hyperparathyroidism can increase trabecular bone when GS expression and cAMP stimulation in osteoblasts are increased but this is not the case in cortical bone where increased GS expression exacerbates cortical bone loss.


Asunto(s)
Hiperparatiroidismo , Osteoblastos , Animales , Huesos/metabolismo , Femenino , Subunidades alfa de la Proteína de Unión al GTP Gs/genética , Subunidades alfa de la Proteína de Unión al GTP Gs/metabolismo , Hiperparatiroidismo/metabolismo , Ratones , Ratones Transgénicos , Osteoblastos/metabolismo , Hormona Paratiroidea/farmacología , Proteínas Wnt
16.
Front Physiol ; 13: 831056, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35309065

RESUMEN

Background: Exercise helps improve glucose handling in diabetes and has been shown to improve mood and cognition in other conditions. Osteocalcin, a protein produced by bone osteoblasts, was reported to have endocrine actions to improve both metabolism and also improve age-related cognitive deficits in mice. Methods: This study was designed to compare the effects of daily treadmill running exercise with injection of osteocalcin in high fat diet (HFD) induced diabetes in male and female C57BL/6J mice. Following established glucose intolerance and treatment for 8 weeks, mice were assessed for anxiety on an elevated plus maze, motivation by tail suspension test and cognition and memory in a puzzle box. Endogenous osteocalcin was measured by ELISA. Results: Mice on HFD had high weight gain, glucose intolerance and increased white fat. Exercise increased circulating osteocalcin levels in female mice but decreased them in male mice. Exercise also decreased weight gain and improved glucose tolerance in female but not male mice; however, treatment with osteocalcin made no metabolic improvements in either males or females. HFD induced anxiety only in female mice and this was not improved by osteocalcin. Exercise induced anxiety only in male mice. HFD also increased depressive-like behavior in both sexes, and this was improved by either exercise or osteocalcin treatment. Cognitive deficits were seen in both male and female mice on HFD. Exercise improved cognitive performance in female but not male mice, while osteocalcin treatment improved cognitive performance in both sexes. Conclusion: There were sex differences in the effects of exercise on endogenous osteocalcin regulation that correlated with improvements in cognitive but not metabolic outcomes. Exogenous osteocalcin did not improve metabolism but was effective in improving HFD-induced cognitive deficits. Sex is an important variable in hormonal and cognitive responses to exercise in diabetes.

17.
BMJ Open Respir Res ; 8(1)2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34556492

RESUMEN

INTRODUCTION: The COVID-19 pandemic has led to over 100 million cases worldwide. The UK has had over 4 million cases, 400 000 hospital admissions and 100 000 deaths. Many patients with COVID-19 suffer long-term symptoms, predominantly breathlessness and fatigue whether hospitalised or not. Early data suggest potentially severe long-term consequence of COVID-19 is development of long COVID-19-related interstitial lung disease (LC-ILD). METHODS AND ANALYSIS: The UK Interstitial Lung Disease Consortium (UKILD) will undertake longitudinal observational studies of patients with suspected ILD following COVID-19. The primary objective is to determine ILD prevalence at 12 months following infection and whether clinically severe infection correlates with severity of ILD. Secondary objectives will determine the clinical, genetic, epigenetic and biochemical factors that determine the trajectory of recovery or progression of ILD. Data will be obtained through linkage to the Post-Hospitalisation COVID platform study and community studies. Additional substudies will conduct deep phenotyping. The Xenon MRI investigation of Alveolar dysfunction Substudy will conduct longitudinal xenon alveolar gas transfer and proton perfusion MRI. The POST COVID-19 interstitial lung DiseasE substudy will conduct clinically indicated bronchoalveolar lavage with matched whole blood sampling. Assessments include exploratory single cell RNA and lung microbiomics analysis, gene expression and epigenetic assessment. ETHICS AND DISSEMINATION: All contributing studies have been granted appropriate ethical approvals. Results from this study will be disseminated through peer-reviewed journals. CONCLUSION: This study will ensure the extent and consequences of LC-ILD are established and enable strategies to mitigate progression of LC-ILD.


Asunto(s)
COVID-19/complicaciones , Enfermedades Pulmonares Intersticiales , Humanos , Estudios Longitudinales , Enfermedades Pulmonares Intersticiales/epidemiología , Estudios Observacionales como Asunto , Pandemias , Estudios Prospectivos , Reino Unido/epidemiología , Síndrome Post Agudo de COVID-19
18.
Front Cell Dev Biol ; 9: 681347, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34497803

RESUMEN

Blood outgrowth smooth muscle cells (BO-SMCs) offer the means to study vascular cells without the requirement for surgery providing opportunities for drug discovery, tissue engineering, and personalized medicine. However, little is known about these cells which meant that their therapeutic potential remains unexplored. Our objective was to investigate for the first time the ability of BO-SMCs and vessel-derived smooth muscle cells to sense the thromboxane mimetic U46619 by measuring intracellular calcium elevation and contraction. U46619 (10-6 M) increased cytosolic calcium in BO-SMCs and vascular smooth muscle cells (VSMCs) but not in fibroblasts. Increased calcium signal peaked between 10 and 20 s after U46619 in both smooth muscle cell types. Importantly, U46619 (10-9 to 10-6 M) induced concentration-dependent contractions of both BO-SMCs and VSMCs but not in fibroblasts. In summary, we show that functional responses of BO-SMCs are in line with VSMCs providing critical evidence of their application in biomedical research.

19.
Br J Pharmacol ; 178(23): 4758-4771, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34383973

RESUMEN

BACKGROUND AND PURPOSE: P2Y12 receptor antagonists reduce platelet aggregation and the incidence of arterial thrombosis. Adenosine signalling in platelets directly affects cyclic nucleotide tone, which we have shown to have a synergistic relationship with P2Y12 inhibition. Several studies suggest that ticagrelor inhibits erythrocyte uptake of adenosine and that this could also contribute to its antiplatelet effects. We therefore examined the effects on platelet activation of adenosine signalling activators in combination with the P2Y12 receptor antagonists ticagrelor and prasugrel. EXPERIMENTAL APPROACH: Human washed platelets, platelet-rich plasma and whole blood were used to test the interactions between ticagrelor or prasugrel and adenosine or 5'-N-ethylcarboxamidoadenosine (NECA). Platelet reactivity to thrombin, protease-activated receptor 1 (PAR-1) activation or collagen was assessed by a combination of 96-well plate aggregometry, light transmission aggregometry, whole blood aggregometry, ATP release assay and levels of cAMP. KEY RESULTS: The inhibitory effects of ticagrelor and prasugrel on platelet aggregation and ATP release were enhanced in the presence of adenosine or NECA. Isobolographic analysis indicated a powerful synergy between P2Y12 receptor inhibition and adenosine signalling activators. Increased levels of cAMP in platelets were also observed. In all cases, ticagrelor showed similar synergistic effects on platelet inhibition as prasugrel in the presence of adenosine or NECA. CONCLUSION AND IMPLICATIONS: These results indicate that P2Y12 antagonists have a synergistic relationship with adenosine signalling and that their efficacy may depend partly upon the presence of endogenous adenosine. This effect was common for prasugrel and ticagrelor despite reports of differences in their effects upon adenosine reuptake.


Asunto(s)
Adenosina , Plaquetas , Antagonistas del Receptor Purinérgico P2Y , Adenosina/metabolismo , Plaquetas/efectos de los fármacos , Humanos , Agregación Plaquetaria , Inhibidores de Agregación Plaquetaria/farmacología , Clorhidrato de Prasugrel/farmacología , Antagonistas del Receptor Purinérgico P2Y/farmacología , Receptores Purinérgicos P2Y12
20.
Sci Adv ; 7(12)2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33741600

RESUMEN

Endothelial cyclooxygenase-1-derived prostanoids, including prostacyclin, have clear cardioprotective roles associated with their anti-thrombotic potential but have also been suggested to have paradoxical pathological activities within arteries. To date it has not been possible to test the importance of this because no models have been available that separate vascular cyclooxygenase-1 products from those generated elsewhere. Here, we have used unique endothelial-specific cyclooxygenase-1 knockout mice to show that endothelial cyclooxygenase-1 produces both protective and pathological products. Functionally, however, the overall effect of these was to drive pathological responses in the context of both vasoconstriction in vitro and the development of atherosclerosis and vascular inflammation in vivo. These data provide the first demonstration of a pathological role for the vascular cyclooxygenase-1 pathway, highlighting its potential as a therapeutic target. They also emphasize that, across biology, the role of prostanoids is not always predictable due to unique balances of context, products, and receptors.


Asunto(s)
Aterosclerosis , Ciclooxigenasa 1/metabolismo , Epoprostenol , Proteínas de la Membrana/metabolismo , Animales , Aterosclerosis/etiología , Ciclooxigenasa 1/genética , Epoprostenol/metabolismo , Ratones , Prostaglandinas , Vasoconstricción
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