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1.
Am J Physiol Heart Circ Physiol ; 326(1): H278-H290, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38038717

RESUMEN

Smoking and high-fat diet (HFD) consumption are two modifiable risk factors for cardiovascular (CV) diseases, and individuals who are overweight or obese due to unhealthy diet are more likely to use tobacco products. In this study, we aim to investigate the combined effects of nicotine (the addictive component of all tobacco products) and HFD on CV health, which are poorly understood. C57BL/6N male mice were placed on either HFD (60 kcal% fat) or regular diet (22 kcal% fat) and exposed to air or nicotine vapor for 10-12 wk. CV function was monitored by echocardiography and radiotelemetry, with left ventricular (LV) catheterization and aortic ring vasoreactivity assays performed at end point. Mice on HFD exhibited increased heart rate and impaired parasympathetic tone, whereas nicotine exposure increased sympathetic vascular tone as evidenced by increased blood pressure (BP) response to ganglionic blockade. Although neither nicotine nor HFD alone or in combination significantly altered BP, nicotine exposure disrupted circadian BP regulation with reduced BP dipping. LV catheterization revealed that combined exposure to nicotine and HFD led to LV diastolic dysfunction with increased LV end-diastolic pressure (LVEDP). Moreover, combined exposure resulted in increased inhibitory phosphorylation of endothelial nitric oxide synthase and greater impairment of endothelium-dependent vasodilation. Finally, a small cohort of C57BL/6N females with combined exposure exhibited similar increases in LVEDP, indicating that both sexes are susceptible to the combined effect of nicotine and HFD. In summary, combined exposure to nicotine and HFD leads to greater CV harm, including both additive and new-onset CV dysfunction.NEW & NOTEWORTHY Nicotine product usage and high-fat diet consumption are two modifiable risk factors for cardiovascular diseases. Here, we demonstrate that in mice, combined exposure to inhaled nicotine and high-fat diet results in unique cardiovascular consequences compared with either treatment alone, including left ventricular diastolic dysfunction, dysregulation of blood pressure, autonomic dysfunction, and greater impairment of endothelium-dependent vasorelaxation. These findings indicate that individuals who consume both nicotine products and high-fat diet have distinctive cardiovascular risks.


Asunto(s)
Dieta Alta en Grasa , Disfunción Ventricular Izquierda , Humanos , Femenino , Ratones , Masculino , Animales , Dieta Alta en Grasa/efectos adversos , Nicotina/toxicidad , Ratones Endogámicos C57BL , Vasodilatación , Presión Sanguínea , Disfunción Ventricular Izquierda/inducido químicamente
2.
J Adv Nurs ; 2023 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-37485721

RESUMEN

AIMS: Healthcare waste production is a significant contributor to carbon emissions, negatively impacting the environment. Ineffective healthcare waste disposal results in greater measures to manage it which is costly to both the environment and healthcare organizations. This study aimed to improve waste management in a tertiary maternity hospital. Specifically, the impact of a midwife-led intervention to improve waste segregation, staff knowledge and attitudes and waste management-related costs was investigated. DESIGN: A multi-method study including pre- and post-intervention staff waste management knowledge and attitude surveys and waste audits of bins located on the postnatal ward. METHODS: The intervention included education sessions, posters and signage by waste bins and monthly newsletters distributed throughout 2021 to raise staff awareness of correct waste segregation processes. Pre- and post-intervention surveys were distributed in early 2021 and early 2022, respectively. The waste audits occurred on three occasions, January, July and December of 2021. The waste audit included total waste in kilograms (kg), waste in kg by segregation and identification of correct and incorrect segregation. Waste audit and quantitative staff survey data were analysed using descriptive statistics and chi square. Qualitative data from the staff surveys were analysed using content analysis. RESULTS: Knowledge and attitudes to waste management were similar across pre- and post-intervention staff surveys. Knowledge of accurate allocation of specific items to waste streams was variable with errors identified in both the pre- and post-surveys. Waste audit data showed reductions in clinical waste at each measurement, with a 71.2% decrease in clinical waste from baseline to the final audit. Accuracy of waste segregation also improved from the baseline to final audit, resulting in a 48% reduction in waste management costs. CONCLUSION: The midwife-led initiative improved waste segregation and achieved the associated waste management cost reduction. IMPACT: A midwifery-led initiative to address waste production and segregation on a maternity ward had a positive impact on waste segregation practices and associated waste management costs. The existence of change champions along with in-service sessions, posters and newsletters to raise awareness of correct waste segregation resulted in a 71% reduction of incorrect items being placed in clinical waste bins. Challenges such as COVID-19 pressures and workload made it difficult for midwives to engage in waste management education and effective waste segregation. PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution. WHAT DOES THIS PAPER CONTRIBUTE TO THE WIDER GLOBAL CLINICAL COMMUNITY?: Implementing clinician-led waste management interventions across hospital wards while addressing workload issues are likely to have significant cost benefits for organisations and minimise the environmental impacts of healthcare settings.

3.
Am J Physiol Heart Circ Physiol ; 323(5): H941-H948, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-36206053

RESUMEN

Electronic cigarette use has increased globally prompting calls for improved understanding of nicotine's cardiovascular health effects. Our group has previously demonstrated that chronic, inhaled nicotine induces pulmonary hypertension and right ventricular (RV) remodeling in male mice, but not female mice, suggesting sex differences in nicotine-related pathology. Clinically, biological females develop pulmonary hypertension more often but have less severe disease than biological males, likely because of the cardiopulmonary protective effects of estrogen. Nicotine is also metabolized more rapidly in biological females because of differences in cytochrome-P450 activity, which are thought to be mediated by female sex hormones. These findings led us to hypothesize that female mice are protected against nicotine-induced pulmonary hypertension by an ovarian hormone-dependent mechanism. In this study, intact and ovariectomized (OVX) female mice were exposed to chronic, inhaled nicotine or room air for 12 h/day for 10-12 wk. We report no differences in serum cotinine levels between intact and OVX mice. In addition, we found no structural (RV or left ventricular dimensions and Fulton index) or functional (RV systolic pressure, pulmonary vascular resistance, cardiac output, ejection fraction, and fractional shortening) evidence of cardiopulmonary dysfunction in intact or OVX mice. We conclude that ovarian hormones do not mediate cardiopulmonary protection against nicotine-induced pulmonary hypertension. Due to profound sex differences in clinical pulmonary hypertension pathogenesis and nicotine metabolism, further studies are necessary to elucidate mechanisms underlying protection from nicotine-induced pathology in female mice.NEW & NOTEWORTHY The emergence of electronic cigarettes poses a threat to cardiovascular and pulmonary health, but the direct contribution of nicotine to these disease processes is largely unknown. Our laboratory has previously shown that chronic, inhaled nicotine induces pulmonary hypertension and right ventricular remodeling in male mice, but not female mice. This study using a bilateral ovariectomy model suggests that the cardiopulmonary protection observed in nicotine-exposed female mice may be independent of ovarian hormones.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Hipertensión Pulmonar , Disfunción Ventricular Derecha , Femenino , Masculino , Ratones , Animales , Hipertensión Pulmonar/inducido químicamente , Hipertensión Pulmonar/prevención & control , Remodelación Ventricular , Nicotina/farmacología , Función Ventricular Derecha , Cotinina/efectos adversos , Arteria Pulmonar , Estrógenos/farmacología , Hormonas Esteroides Gonadales , Citocromos/farmacología , Disfunción Ventricular Derecha/inducido químicamente , Disfunción Ventricular Derecha/prevención & control
4.
Clin Sci (Lond) ; 136(12): 973-987, 2022 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-35678315

RESUMEN

Cigarette smoking remains the leading modifiable risk factor for cardiopulmonary diseases; however, the effects of nicotine alone on cardiopulmonary function remain largely unknown. Previously, we have shown that chronic nicotine vapor inhalation in mice leads to the development of pulmonary hypertension (PH) with right ventricular (RV) remodeling. The present study aims to further examine the cardiopulmonary effects of nicotine and the role of the α7 nicotinic acetylcholine receptor (α7-nAChR), which is widely expressed in the cardiovascular system. Wild-type (WT) and α7-nAChR knockout (α7-nAChR-/-) mice were exposed to room air (control) or nicotine vapor daily for 12 weeks. Consistent with our previous study, echocardiography and RV catheterization reveal that male WT mice developed increased RV systolic pressure with RV hypertrophy and dilatation following 12-week nicotine vapor exposure; in contrast, these changes were not observed in male α7-nAChR-/- mice. In addition, chronic nicotine inhalation failed to induce PH and RV remodeling in female mice regardless of genotype. The effects of nicotine on the vasculature were further examined in male mice. Our results show that chronic nicotine inhalation led to impaired acetylcholine-mediated vasodilatory response in both thoracic aortas and pulmonary arteries, and these effects were accompanied by altered endothelial nitric oxide synthase phosphorylation (enhanced inhibitory phosphorylation at threonine 495) and reduced plasma nitrite levels in WT but not α7-nAChR-/- mice. Finally, RNA sequencing revealed up-regulation of multiple inflammatory pathways in thoracic aortas from WT but not α7-nAChR-/- mice. We conclude that the α7-nAChR mediates chronic nicotine inhalation-induced PH, RV remodeling and vascular dysfunction.


Asunto(s)
Nicotina , Receptor Nicotínico de Acetilcolina alfa 7 , Acetilcolina/metabolismo , Administración por Inhalación , Animales , Aorta Torácica/efectos de los fármacos , Femenino , Masculino , Ratones , Nicotina/administración & dosificación , Arteria Pulmonar/efectos de los fármacos , Regulación hacia Arriba , Vasodilatación/efectos de los fármacos , Receptor Nicotínico de Acetilcolina alfa 7/genética , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo
5.
Nicotine Tob Res ; 24(9): 1363-1370, 2022 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-35271725

RESUMEN

INTRODUCTION: The impact of nicotine, the addictive component of both traditional cigarettes and e-cigarettes, on many physiological processes remains poorly understood. To date, there have been few investigations into the impact of nicotine on the gut microbiome, and these studies utilized oral administration rather than inhalation. This study aimed to establish if inhaled nicotine alters the gut microbiome and the effect of sex as a biological variable. METHODS: Female (n = 8 air; n = 10 nicotine) and male (n = 10 air; n = 10 nicotine) C57BL6/J mice were exposed to air (control) or nicotine vapor (12 hour/day) for 13 weeks. A fecal sample was collected from each mouse at the time of sacrifice, and the gut microbiome was analyzed by 16S rRNA gene sequencing. QIIME2, PICRUSt, and STAMP were used to detect gut bacterial differences and functional metabolic pathways. RESULTS: Sex-specific differences were observed in both alpha and beta diversities in the absence of nicotine. While nicotine alters microbial community structure in both male and female mice as revealed by the beta diversity metric, nicotine significantly reduced alpha diversity only in female mice. A total of 42 bacterial taxa from phylum to species were found to be significantly different among the treatment groups. Finally, analysis for functional genes revealed significant differences in twelve metabolic pathways in female mice and ten in male mice exposed to nicotine compared to air controls. CONCLUSIONS: Nicotine inhalation alters the gut microbiome and reduces bacterial diversity in a sex-specific manner, which may contribute to the overall adverse health impact of nicotine. IMPLICATIONS: The gut microbiota plays a fundamental role in the well-being of the host, and traditional cigarette smoking has been shown to affect the gut microbiome. The effects of nicotine alone, however, remain largely uncharacterized. Our study demonstrates that nicotine inhalation alters the gut microbiome in a sex-specific manner, which may contribute to the adverse health consequences of inhaled nicotine. This study points to the importance of more detailed investigations into the influence of inhaled nicotine on the gut microbiota.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Microbioma Gastrointestinal , Animales , Bacterias , Heces/microbiología , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Nicotina/efectos adversos , ARN Ribosómico 16S/genética
6.
Am J Physiol Heart Circ Physiol ; 320(4): H1526-H1534, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33577434

RESUMEN

Use of electronic cigarettes is rapidly increasing among youth and young adults, but little is known regarding the long-term cardiopulmonary health impacts of these nicotine-containing devices. Our group has previously demonstrated that chronic, inhaled nicotine induces pulmonary hypertension (PH) and right ventricular (RV) remodeling in mice. These changes were associated with upregulated RV angiotensin-converting enzyme (ACE). Angiotensin II receptor blockers (ARBs) have been shown to reverse cigarette smoking-induced PH in rats. ACE inhibitor and ARB use in a large retrospective cohort of patients with PH is associated with improved survival. Here, we utilized losartan (an ARB specific for angiotensin II type 1 receptor) to further explore nicotine-induced PH. Male C57BL/6 mice received nicotine vapor for 12 h/day, and exposure was assessed using serum cotinine to achieve levels comparable to human smokers or electronic cigarette users. Mice were exposed to nicotine for 8 wk and a subset was treated with losartan via an osmotic minipump. Cardiac function was assessed using echocardiography and catheterization. Although nicotine exposure increased angiotensin II in the RV and lung, this finding was nonsignificant. Chronic, inhaled nicotine significantly increased RV systolic pressure and RV free wall thickness versus air control. These parameters were significantly lower in mice receiving both nicotine and losartan. Nicotine significantly increased RV internal diameter, with no differences seen between the nicotine and nicotine-losartan group. Neither nicotine nor losartan affected left ventricular structure or function. These findings provide the first evidence that antagonism of the angiotensin II type 1 receptor can ameliorate chronic, inhaled nicotine-induced PH and RV remodeling.NEW & NOTEWORTHY Chronic, inhaled nicotine causes pulmonary hypertension and right ventricular remodeling in mice. Treatment with losartan, an angiotensin II type 1 receptor antagonist, ameliorates nicotine-induced pulmonary hypertension and right ventricular remodeling. This novel finding provides preclinical evidence for the use of renin-angiotensin system-based therapies in the treatment of pulmonary hypertension, particularly in patients with a history of tobacco-product use.


Asunto(s)
Presión Arterial , Cigarrillo Electrónico a Vapor , Hipertensión Pulmonar/metabolismo , Hipertrofia Ventricular Derecha/metabolismo , Nicotina , Arteria Pulmonar/metabolismo , Receptor de Angiotensina Tipo 1/metabolismo , Función Ventricular Derecha , Remodelación Ventricular , Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Animales , Presión Arterial/efectos de los fármacos , Modelos Animales de Enfermedad , Hipertensión Pulmonar/inducido químicamente , Hipertensión Pulmonar/fisiopatología , Hipertensión Pulmonar/prevención & control , Hipertrofia Ventricular Derecha/inducido químicamente , Hipertrofia Ventricular Derecha/patología , Hipertrofia Ventricular Derecha/prevención & control , Exposición por Inhalación , Losartán/farmacología , Masculino , Ratones Endogámicos C57BL , Arteria Pulmonar/efectos de los fármacos , Arteria Pulmonar/fisiopatología , Receptor de Angiotensina Tipo 1/efectos de los fármacos , Transducción de Señal , Factores de Tiempo , Función Ventricular Derecha/efectos de los fármacos , Remodelación Ventricular/efectos de los fármacos
7.
Int J Obes (Lond) ; 45(8): 1773-1781, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34002038

RESUMEN

OBJECTIVE: The prevalence of obesity is growing globally. Adiposity increases the risk for metabolic syndrome, type 2 diabetes and cardiovascular disease. Adipose tissue distribution influences systemic metabolism and impacts metabolic disease risk. The link between sexual dimorphisms of adiposity and metabolism is poorly defined. We hypothesise that depot-specific adipose tissue mitochondrial function contributes to the sexual dimorphism of metabolic flexibility in obesity. METHODS: Male and female mice fed high fat diet (HFD) or standard diet (STD) from 8-18 weeks of age underwent whole animal calorimetry and high-resolution mitochondrial respirometry analysis on adipose tissue depots. To determine translatability we used RT-qPCR to examine key brown adipocyte-associated gene expression: peroxisome proliferator-activated receptor co-activator 1α, Uncoupling protein 1 and cell death inducing DFFA like effector a in brown adipose tissue (BAT) and subcutaneous adipose tissue (sWAT) of 18-week-old mice and sWAT from human volunteers. RESULTS: Male mice exhibited greater weight gain compared to female mice when challenged with HFD. Relative to increased body mass, the adipose to body weight ratio for BAT and sWAT depots was increased in HFD-fed males compared to female HFD-fed mice. Oxygen consumption, energy expenditure, respiratory exchange ratio and food consumption did not differ between males and females fed HFD. BAT mitochondria from obese females showed increased Complex I & II respiration and maximal respiration compared to lean females whereas obese males did not exhibit adaptive mitochondrial BAT respiration. Sexual dimorphism in BAT-associated gene expression in sWAT was also associated with Body Mass Index in humans. CONCLUSIONS: We show that sexual dimorphism of weight gain is reflected in mitochondrial respiration analysis. Female mice have increased metabolic flexibility to adapt to changes in energy intake by regulating energy expenditure through increased complex II and maximal mitochondrial respiration within BAT when HFD challenged and increased proton leak in sWAT mitochondria.


Asunto(s)
Tejido Adiposo , Mitocondrias/metabolismo , Obesidad/metabolismo , Caracteres Sexuales , Tejido Adiposo/citología , Tejido Adiposo/metabolismo , Animales , Modelos Animales de Enfermedad , Femenino , Masculino , Ratones
8.
Front Cardiovasc Med ; 9: 993617, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36277777

RESUMEN

Background: The heart undergoes structural and functional changes in response to injury and hemodynamic stress known as cardiac remodeling. Cardiac remodeling often decompensates causing dysfunction and heart failure (HF). Cardiac remodeling and dysfunction are significantly associated with cigarette smoking. Although cigarette smoking has declined, the roles of nicotine and novel tobacco products (including electronic cigarettes and heat-not-burn tobacco) in cardiac remodeling are unclear. In this perspective, we present evidence demonstrating maladaptive cardiac remodeling in nicotine-exposed mice undergoing hemodynamic stress with angiotensin (Ang)-II infusion and review preclinical literature linking nicotine and novel tobacco products with cardiac remodeling and dysfunction. Methods: Adult, male C57BL/6J mice were exposed to room air or chronic, inhaled nicotine for 8 weeks. A subset of mice was infused with Ang-II via subcutaneous osmotic mini-pumps during the final 4 weeks of exposure. Left ventricular structure and function were assessed with echocardiography. Results: Chronic, inhaled nicotine abrogated Ang-II-induced thickening of the left ventricular posterior wall, leading to reduced relative wall thickness. Ang-II infusion was associated with increased left ventricular mass index in both air- and nicotine-exposed mice. Conclusions: These changes suggest a phenotypic shift from concentric hypertrophy to eccentric hypertrophy in nicotine-exposed, hemodynamically-stressed mice which could drive HF pathogenesis. These findings join a growing body of animal studies demonstrating cardiac remodeling and dysfunction following nicotine and electronic cigarette exposure. Further exploration is necessary; however, clinicians and researchers should not overlook these emerging products as potential risk factors in the pathogenesis of cardiac remodeling and associated diseases including HF.

9.
Nat Commun ; 13(1): 1748, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35365625

RESUMEN

The endoplasmic reticulum (ER) regulates cellular protein and lipid biosynthesis. ER dysfunction leads to protein misfolding and the unfolded protein response (UPR), which limits protein synthesis to prevent cytotoxicity. Chronic ER stress in skeletal muscle is a unifying mechanism linking lipotoxicity to metabolic disease. Unidentified signals from cells undergoing ER stress propagate paracrine and systemic UPR activation. Here, we induce ER stress and lipotoxicity in myotubes. We observe ER stress-inducing lipid cell non-autonomous signal(s). Lipidomics identifies that palmitate-induced cell stress induces long-chain ceramide 40:1 and 42:1 secretion. Ceramide synthesis through the ceramide synthase 2 de novo pathway is regulated by UPR kinase Perk. Inactivation of CerS2 in mice reduces systemic and muscle ceramide signals and muscle UPR activation. The ceramides are packaged into extracellular vesicles, secreted and induce UPR activation in naïve myotubes through dihydroceramide accumulation. This study furthers our understanding of ER stress by identifying UPR-inducing cell non-autonomous signals.


Asunto(s)
Ceramidas , Estrés del Retículo Endoplásmico , Animales , Ceramidas/metabolismo , Retículo Endoplásmico/metabolismo , Estrés del Retículo Endoplásmico/fisiología , Ratones , Músculo Esquelético/metabolismo , Respuesta de Proteína Desplegada
10.
Liver Cancer ; 11(6): 540-557, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36589727

RESUMEN

Introduction: Heparin sulphate proteoglycans in the liver tumour microenvironment (TME) are key regulators of cell signalling, modulated by sulfatase-2 (SULF2). SULF2 overexpression occurs in hepatocellular carcinoma (HCC). Our aims were to define the nature and impact of SULF2 in the HCC TME. Methods: In liver biopsies from 60 patients with HCC, expression and localization of SULF2 were analysed associated with clinical parameters and outcome. Functional and mechanistic impacts were assessed with immunohistochemistry (IHC), in silico using The Cancer Genome Atlas (TGCA), in primary isolated cancer activated fibroblasts, in monocultures, in 3D spheroids, and in an independent cohort of 20 patients referred for sorafenib. IHC targets included αSMA, glypican-3, ß-catenin, RelA-P-ser536, CD4, CD8, CD66b, CD45, CD68, and CD163. SULF2 impact of peripheral blood mononuclear cells was assessed by migration assays, with characterization of immune cell phenotype using fluorescent activated cell sorting. Results: We report that while SULF2 was expressed in tumour cells in 15% (9/60) of cases, associated with advanced tumour stage and type 2 diabetes, SULF2 was more commonly expressed in cancer-associated fibroblasts (CAFs) (52%) and independently associated with shorter survival (7.2 vs. 29.2 months, p = 0.003). Stromal SULF2 modulated glypican-3/ß-catenin signalling in vitro, although in vivo associations suggested additional mechanisms underlying the CAF-SULF2 impact on prognosis. Stromal SULF2 was released by CAFS isolated from human HCC. It was induced by TGFß1, promoted HCC proliferation and sorafenib resistance, with CAF-SULF2 linked to TGFß1 and immune exhaustion in TGCA HCC patients. Autocrine activation of PDGFRß/STAT3 signalling was evident in stromal cells, with the release of the potent monocyte/macrophage chemoattractant CCL2 in vitro. In human PBMCs, SULF2 preferentially induced the migration of macrophage precursors (monocytes), inducing a phenotypic change consistent with immune exhaustion. In human HCC tissues, CAF-SULF2 was associated with increased macrophage recruitment, with tumouroid studies showing stromal-derived SULF2-induced paracrine activation of the IKKß/NF-κB pathway, tumour cell proliferation, invasion, and sorafenib resistance. Conclusion: SULF2 derived from CAFs modulates glypican-3/ß-catenin signalling but also the HCC immune TME, associated with tumour progression and therapy resistance via activation of the TAK1/IKKß/NF-κB pathway. It is an attractive target for combination therapies for patients with HCC.

11.
Acta Physiol (Oxf) ; 231(4): e13631, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33595878

RESUMEN

Cigarette smoking is the single most important risk factor for the development of cardiovascular diseases (CVDs). However, the role of nicotine, the addictive component of all tobacco products, in the development of CVD is incompletely understood. Although increased public awareness of the harms of cigarette smoking has successfully led to a decline in its prevalence, the use of electronic cigarettes (e-cig) or electronic nicotine delivery system has increased dramatically in recent years because of the perception that these products are safe. This review summarizes our current knowledge of the expression and function of the nicotinic acetylcholine receptors in the cardiovascular system and the impact of nicotine exposure on cardiovascular health, with a focus on nicotine-induced vascular dysfunction. Nicotine alters vasoreactivity through endothelium-dependent and/or endothelium-independent mechanisms, leading to clinical manifestations in both cigarette smokers and e-cig users. In addition, nicotine induces vascular remodelling through its effects on proliferation, migration and matrix production of both vascular endothelial and vascular smooth muscle cells. The purpose of this review is to identify critical knowledge gaps regarding the effects of nicotine on the vasculature and to stimulate continued nicotine research.


Asunto(s)
Enfermedades Cardiovasculares , Sistemas Electrónicos de Liberación de Nicotina , Receptores Nicotínicos , Enfermedades Cardiovasculares/inducido químicamente , Endotelio Vascular , Humanos , Nicotina/efectos adversos
12.
Sci Rep ; 11(1): 16727, 2021 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-34408183

RESUMEN

The prevalence of obesity and non-alcoholic fatty liver disease (NAFLD) associated hepatocellular carcinoma (HCC) is rising, even in the absence of cirrhosis. We aimed to develop a murine model that would facilitate further understanding of NAFLD-HCC pathogenesis. A total of 144 C3H/He mice were fed either control or American lifestyle (ALIOS) diet, with or without interventions, for up to 48 weeks of age. Gross, liver histology, immunohistochemistry (IHC) and RNA-sequencing data were interpreted alongside human datasets. The ALIOS diet promoted obesity, elevated liver weight, impaired glucose tolerance, non-alcoholic fatty liver disease (NAFLD) and spontaneous HCC. Liver weight, fasting blood glucose, steatosis, lobular inflammation and lipogranulomas were associated with development of HCC, as were markers of hepatocyte proliferation and DNA damage. An antioxidant diminished cellular injury, fibrosis and DNA damage, but not lobular inflammation, lipogranulomas, proliferation and HCC development. An acquired CD44 phenotype in macrophages was associated with type 2 diabetes and NAFLD-HCC. In this diet induced NASH and HCC (DINAH) model, key features of obesity associated NAFLD-HCC have been reproduced, highlighting roles for hepatic steatosis and proliferation, with the acquisition of lobular inflammation and CD44 positive macrophages in the development of HCC-even in the absence of progressive injury and fibrosis.


Asunto(s)
Carcinoma Hepatocelular , Complicaciones de la Diabetes , Diabetes Mellitus Tipo 2 , Dieta Alta en Grasa/efectos adversos , Neoplasias Hepáticas , Enfermedad del Hígado Graso no Alcohólico , Anciano , Animales , Carcinoma Hepatocelular/epidemiología , Carcinoma Hepatocelular/etiología , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Complicaciones de la Diabetes/epidemiología , Complicaciones de la Diabetes/metabolismo , Complicaciones de la Diabetes/patología , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patología , Femenino , Humanos , Cirrosis Hepática/complicaciones , Cirrosis Hepática/epidemiología , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Masculino , Ratones , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología
13.
Nat Commun ; 12(1): 1905, 2021 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-33772024

RESUMEN

Brown and beige adipose tissue are emerging as distinct endocrine organs. These tissues are functionally associated with skeletal muscle, adipose tissue metabolism and systemic energy expenditure, suggesting an interorgan signaling network. Using metabolomics, we identify 3-methyl-2-oxovaleric acid, 5-oxoproline, and ß-hydroxyisobutyric acid as small molecule metabokines synthesized in browning adipocytes and secreted via monocarboxylate transporters. 3-methyl-2-oxovaleric acid, 5-oxoproline and ß-hydroxyisobutyric acid induce a brown adipocyte-specific phenotype in white adipocytes and mitochondrial oxidative energy metabolism in skeletal myocytes both in vitro and in vivo. 3-methyl-2-oxovaleric acid and 5-oxoproline signal through cAMP-PKA-p38 MAPK and ß-hydroxyisobutyric acid via mTOR. In humans, plasma and adipose tissue 3-methyl-2-oxovaleric acid, 5-oxoproline and ß-hydroxyisobutyric acid concentrations correlate with markers of adipose browning and inversely associate with body mass index. These metabolites reduce adiposity, increase energy expenditure and improve glucose and insulin homeostasis in mouse models of obesity and diabetes. Our findings identify beige adipose-brown adipose-muscle physiological metabokine crosstalk.


Asunto(s)
Tejido Adiposo Beige/metabolismo , Tejido Adiposo Pardo/metabolismo , Metabolismo Energético/genética , Homeostasis/genética , Transducción de Señal/genética , Adipocitos Marrones/metabolismo , Adipocitos Blancos/metabolismo , Tejido Adiposo Beige/citología , Tejido Adiposo Pardo/citología , Animales , Línea Celular , Células Cultivadas , Cromatografía Liquida , Cromatografía de Gases y Espectrometría de Masas , Perfilación de la Expresión Génica/métodos , Humanos , Masculino , Espectrometría de Masas , Metabolómica/métodos , Ratones Endogámicos C57BL
14.
Diabetes ; 69(5): 893-901, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32086288

RESUMEN

An aging global population combined with sedentary lifestyles and unhealthy diets has contributed to an increasing incidence of obesity and type 2 diabetes. These metabolic disorders are associated with perturbations to nitric oxide (NO) signaling and impaired glucose metabolism. Dietary inorganic nitrate, found in high concentration in green leafy vegetables, can be converted to NO in vivo and demonstrates antidiabetic and antiobesity properties in rodents. Alongside tissues including skeletal muscle and liver, white adipose tissue is also an important physiological site of glucose disposal. However, the distinct molecular mechanisms governing the effect of nitrate on adipose tissue glucose metabolism and the contribution of this tissue to the glucose-tolerant phenotype remain to be determined. Using a metabolomic and stable-isotope labeling approach, combined with transcriptional analysis, we found that nitrate increases glucose uptake and oxidative catabolism in primary adipocytes and white adipose tissue of nitrate-treated rats. Mechanistically, we determined that nitrate induces these phenotypic changes in primary adipocytes through the xanthine oxidoreductase-catalyzed reduction of nitrate to NO and independently of peroxisome proliferator-activated receptor-α. The nitrate-mediated enhancement of glucose uptake and catabolism in white adipose tissue may be a key contributor to the antidiabetic effects of this anion.


Asunto(s)
Tejido Adiposo Blanco/efectos de los fármacos , Tejido Adiposo Blanco/metabolismo , Glucosa/metabolismo , Nitratos/farmacología , Óxido Nítrico/metabolismo , Xantina Deshidrogenasa/metabolismo , Adipocitos/efectos de los fármacos , Adipocitos/metabolismo , Animales , Células Cultivadas , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación Enzimológica de la Expresión Génica/fisiología , Masculino , Metabolismo , Nitratos/administración & dosificación , Oxidación-Reducción , Ratas , Ratas Wistar
15.
J Cachexia Sarcopenia Muscle ; 11(2): 394-404, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31863644

RESUMEN

BACKGROUND: Patients with coexistent chronic heart failure (CHF) and diabetes mellitus (DM) demonstrate greater exercise limitation and worse prognosis compared with CHF patients without DM, even when corrected for cardiac dysfunction. Understanding the origins of symptoms in this subgroup may facilitate development of targeted treatments. We therefore characterized the skeletal muscle phenotype and its relationship to exercise limitation in patients with diabetic heart failure (D-HF). METHODS: In one of the largest muscle sampling studies in a CHF population, pectoralis major biopsies were taken from age-matched controls (n = 25), DM (n = 10), CHF (n = 52), and D-HF (n = 28) patients. In situ mitochondrial function and reactive oxygen species, fibre morphology, capillarity, and gene expression analyses were performed and correlated to whole-body exercise capacity. RESULTS: Mitochondrial respiration, content, coupling efficiency, and intrinsic function were lower in D-HF patients compared with other groups (P < 0.05). A unique mitochondrial complex I dysfunction was present in D-HF patients only (P < 0.05), which strongly correlated to exercise capacity (R2 = 0.64; P < 0.001). Mitochondrial impairments in D-HF corresponded to higher levels of mitochondrial reactive oxygen species (P < 0.05) and lower gene expression of anti-oxidative enzyme superoxide dismutase 2 (P < 0.05) and complex I subunit NDUFS1 (P < 0.05). D-HF was also associated with severe fibre atrophy (P < 0.05) and reduced local fibre capillarity (P < 0.05). CONCLUSIONS: Patients with D-HF develop a specific skeletal muscle pathology, characterized by mitochondrial impairments, fibre atrophy, and derangements in the capillary network that are linked to exercise intolerance. These novel preliminary data support skeletal muscle as a potential therapeutic target for treating patients with D-HF.


Asunto(s)
Complicaciones de la Diabetes/complicaciones , Insuficiencia Cardíaca/complicaciones , Músculo Esquelético/patología , Anciano , Enfermedad Crónica , Femenino , Humanos , Masculino
16.
PLoS One ; 14(1): e0210528, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30650155

RESUMEN

Genetic analyses provide a powerful tool with which to identify the biological components of historical objects. Te Tiriti o Waitangi | The Treaty of Waitangi is New Zealand's founding document, intended to be a partnership between the indigenous Maori and the British Crown. Here we focus on an archived piece of blank parchment that has been proposed to be the missing portion of the lower parchment of the Waitangi Sheet of the Treaty. However, its physical dimensions and characteristics are not consistent with this hypothesis. We perform genetic analyses on the parchment membranes of the Treaty, plus the blank piece of parchment. We find that all three parchments were made from ewes and that the blank parchment is highly likely to be a portion cut from the lower membrane of the Waitangi Sheet because they share identical whole mitochondrial genomes, including an unusual heteroplasmic site. We suggest that the differences in size and characteristics between the two pieces of parchment may have resulted from the Treaty's exposure to water in the early 20th century and the subsequent repair work, light exposure during exhibition or the later conservation treatments in the 1970s and 80s. The blank piece of parchment will be valuable for comparison tests to study the effects of earlier treatments and to monitor the effects of long-term display on the Treaty.


Asunto(s)
Equidad en Salud/legislación & jurisprudencia , Política de Salud/legislación & jurisprudencia , Servicios de Salud del Indígena/legislación & jurisprudencia , Cooperación Internacional , Animales , Identificación Biométrica/métodos , ADN Mitocondrial/clasificación , ADN Mitocondrial/aislamiento & purificación , Femenino , Pruebas Genéticas/métodos , Genoma Mitocondrial/genética , Humanos , Nueva Zelanda , Filogenia , Ovinos/genética , Reino Unido
17.
Aust N Z J Obstet Gynaecol ; 48(4): 391-7, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18837845

RESUMEN

AIM: This study aims to describe pregnancy outcomes for a population-based sample of New Zealand women, and to explore the relationship between lifetime experience of intimate partner violence (IPV) and two non-birth pregnancy outcomes: spontaneous abortion (miscarriage) and termination of pregnancy (abortion). METHODS: Face-to-face interviews were conducted with a random sample of 2391 women who had ever been pregnant, aged 18-64 years old, in two regions (urban and rural). Both outcome measures were determined by asking women if they had ever had a miscarriage or an abortion. Analyses were conducted using logistic regression. RESULTS: Almost one in three ever-pregnant women reported having at least one miscarriage, and at least one in ten reported terminating a pregnancy. Even controlling for potential confounders, women who had ever experienced IPV were 1.4 times more likely to report they had ever had a miscarriage compared with women who had never experienced violence (P = 0.008), and were 2.5 times more likely to report they had ever had an abortion (P < 0.0001). Ethnicity was significantly associated with experiencing a miscarriage (Asian and Pacific women were less likely compared with European/Pakeha women), and having ever had an abortion (Asian women were 3.5 times more likely compared with Pakeha women). CONCLUSIONS: In this population-based sample, miscarriage was relatively common, as was termination of pregnancy. IPV was significantly associated with both induced and spontaneous abortion. Healthcare settings that see women experiencing these pregnancy outcomes need to be cognisant of the link with current and historical IPV, and be able to respond to women appropriately.


Asunto(s)
Aborto Inducido/estadística & datos numéricos , Aborto Espontáneo/epidemiología , Maltrato Conyugal/estadística & datos numéricos , Adolescente , Adulto , Estudios Transversales , Femenino , Humanos , Entrevistas como Asunto , Persona de Mediana Edad , Nueva Zelanda , Oportunidad Relativa , Embarazo , Resultado del Embarazo , Prevalencia , Adulto Joven
18.
Aust N Z J Obstet Gynaecol ; 48(4): 398-404, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18837846

RESUMEN

AIM: To explore the extent of intimate partner violence during pregnancy and its association with pregnancy intendedness and pregnancy-related behaviours among a representative sample of New Zealand women. METHODS: Face-to-face interviews were conducted with a representative sample of 2391 women who had ever been pregnant, aged 18-64 years old in two regions (urban and rural) in New Zealand. RESULTS: Six per cent of urban women and 9% of rural women had ever experienced violence during pregnancy; approximately 40% of these had experienced violence in more than one pregnancy. Women who had experienced violence in pregnancy, compared with those who had not, were less likely to report their last pregnancy had been wanted at that time (28% vs 55%), and less likely to report that their partner wanted the pregnancy (40% vs 57%). Antenatal and postnatal care attendance was almost universal during the last pregnancy. Women who had experienced violence during pregnancy were more likely to smoke tobacco during pregnancy (67% vs 22%, P < 0.0001), and more commonly, consumed alcohol (31% vs 20%, not significant). For the most recent pregnancy in which women had experienced violence, most was perpetrated by the child's biological father (96%), and most women (74%) reported that the same man had also beaten her before she was pregnant. CONCLUSIONS: Violence during pregnancy is a significant problem for New Zealand women, with negative health implications for both women and their children. Active intervention and support is necessary to mitigate potential consequences.


Asunto(s)
Embarazo/estadística & datos numéricos , Maltrato Conyugal/estadística & datos numéricos , Adolescente , Adulto , Consumo de Bebidas Alcohólicas/epidemiología , Mujeres Maltratadas/estadística & datos numéricos , Estudios Transversales , Femenino , Humanos , Entrevistas como Asunto , Persona de Mediana Edad , Nueva Zelanda/epidemiología , Atención Posnatal/estadística & datos numéricos , Embarazo no Deseado , Atención Prenatal/estadística & datos numéricos , Prevalencia , Fumar/epidemiología , Adulto Joven
19.
Regen Biomater ; 5(3): 167-175, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29942649

RESUMEN

Coordinated investigations into the interactions between biologically mimicking (biomimetic) material constructs and stem cells advance the potential for the regeneration and possible direct replacement of diseased cells and tissues. Any clinically relevant therapies will require the development and optimization of methods that mass produce fully functional cells and tissues. Despite advances in the design and synthesis of biomaterial scaffolds, one of the biggest obstacles facing tissue engineering is understanding how specific extracellular cues produced by biomaterial scaffolds influence the proliferation and differentiation of various cell sources. Matrix elasticity is one such tailorable property of synthetic scaffolds that is known to differ between tissues. Here, we investigate the interactions between an elastically tailorable polyethylene glycol (PEG)-based hydrogel platform and human bone marrow-derived mesenchymal stem cells (hMSCs). For these studies, two different hydrogel compositions with elastic moduli in the ranges of 50-60 kPa and 8-10 kPa were implemented. Our findings demonstrate that the different elasticities in this platform can produce changes in hMSC morphology and proliferation, indicating that the platform can be implemented to produce changes in hMSC behavior and cell state for a broad range of tissue engineering and regenerative applications. Furthermore, we show that the platform's different elasticities influence stem cell differentiation potential, particularly when promoting stem cell differentiation toward cell types from tissues with stiffer elasticity. These findings add to the evolving and expanding library of information on stem cell-biomaterial interactions and opens the door for continued exploration into PEG-based hydrogel scaffolds for tissue engineering and regenerative medicine applications.

20.
ACS Biomater Sci Eng ; 3(8): 1494-1498, 2017 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-33429636

RESUMEN

Advanced cellular biomanufacturing requires the large-scale production of biocompatible materials that can be utilized in the study of cell-matrix interactions and directed stem cell differentiation as well as the generation of physiologically relevant tissues for therapeutic applications. Herein we describe the development of a hydrogel based platform with tailorable mechanical properties that supports the attachment and proliferation of both pluripotent and multipotent stem cells. The biomimetic hydrogel scaffold generated provides biocompatible compositions for generating various tissue-like elasticities for regenerative medicine applications and advanced biomanufacturing.

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