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1.
Physiol Rep ; 11(23): e15869, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38054572

RESUMEN

Long ncRNAs (lncRNAs) have been shown to play a biological and physiological role in various tissues including the heart. We and others have previously established that the lncRNA Oip5os1 (1700020I14Rik, OIP5-AS1, Cyrano) is enriched in striated muscles, and its deletion in mice leads to defects in both skeletal and cardiac muscle function. In the present study, we investigated the impact of global Oip5os1 deletion on cardiac function in the setting of streptozotocin (STZ)-induced diabetes. Specifically, we studied male WT and KO mice with or without diabetes for 24 weeks, and phenotyped animals for metabolic and cardiac endpoints. Independent of genotype, diabetes was associated with left ventricular diastolic dysfunction based on a fall in E'/A' ratio. Deletion of Oip5os1 in a setting of diabetes had no significant impact on ventricular function or ventricular weight, but was associated with left atrial dysfunction (reduced fractional shortening) and myopathy which was associated with anesthesia intolerance and premature death in the majority of KO mice tested during cardiac functional assessment. This atrial phenotype was not observed in WT diabetic mice. The most striking molecular difference was a reduction in the metabolic regulator ERRalpha in the atria of KO mice compared with WT mice. There was also a trend for a reduction in Serca2a. These findings highlight Oip5os1 as a gene of interest in aspects of atrial function in the setting of diabetes, highlighting an additional functional role for this lncRNA in cardiac pathological settings.


Asunto(s)
Fibrilación Atrial , Diabetes Mellitus Experimental , ARN Largo no Codificante , Animales , Masculino , Ratones , Fibrilación Atrial/complicaciones , Fibrilación Atrial/genética , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/patología , Atrios Cardíacos/metabolismo , Atrios Cardíacos/patología , Miocardio/patología , ARN Largo no Codificante/genética
2.
J Endocrinol ; 259(2)2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37725394

RESUMEN

Type 2 diabetes mellitus (T2DM), a condition characterised by insulin resistance (IR) and skeletal muscle mitochondrial abnormalities, is a leading cause of death in developed societies. Much work has postulated that improving pathways linked to mitochondrial health, including autophagy, may be a potential avenue to prevent or treat T2DM. Given the recent data indicating a role for tripartite motif-containing 28 (TRIM28) in autophagy and mitochondrial pathways, we investigated whether muscle-specific deletion of TRIM28 might impact on obesity, glucose tolerance, and IR in mice. We studied two different muscle-specific (MCK-cre and ACTA1-cre-ERT2) TRIM28 knockout models, which were phenotyped during and after being fed a chow or high-fat diet (HFD). Whilst muscle-specific deletion of TRIM28 in both models demonstrated alterations in markers of mitochondrial activity and autophagy in skeletal muscle, we did not observe major impacts on the majority of metabolic measures in these mice. Specifically, we demonstrate that deletion of TRIM28 in skeletal muscle of mice during (MCK-cre) or post-development (ACTA1-cre-ERT2) does not prevent HFD-induced obesity or glucose intolerance. These findings are consistent with those reported previously in relation to autophagy and mitochondria in other cell types, and thus warrant further study into the biological role TRIM28 has in relation to mitochondrial function.


Asunto(s)
Diabetes Mellitus Tipo 2 , Intolerancia a la Glucosa , Resistencia a la Insulina , Ratones , Animales , Diabetes Mellitus Tipo 2/metabolismo , Resistencia a la Insulina/genética , Músculo Esquelético/metabolismo , Intolerancia a la Glucosa/metabolismo , Obesidad/metabolismo , Dieta Alta en Grasa/efectos adversos , Ratones Endogámicos C57BL , Mitocondrias Musculares/metabolismo , Proteína 28 que Contiene Motivos Tripartito/metabolismo
3.
Elife ; 122023 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-37000167

RESUMEN

Cardiometabolic diseases encompass a range of interrelated conditions that arise from underlying metabolic perturbations precipitated by genetic, environmental, and lifestyle factors. While obesity, dyslipidaemia, smoking, and insulin resistance are major risk factors for cardiometabolic diseases, individuals still present in the absence of such traditional risk factors, making it difficult to determine those at greatest risk of disease. Thus, it is crucial to elucidate the genetic, environmental, and molecular underpinnings to better understand, diagnose, and treat cardiometabolic diseases. Much of this information can be garnered using systems genetics, which takes population-based approaches to investigate how genetic variance contributes to complex traits. Despite the important advances made by human genome-wide association studies (GWAS) in this space, corroboration of these findings has been hampered by limitations including the inability to control environmental influence, limited access to pertinent metabolic tissues, and often, poor classification of diseases or phenotypes. A complementary approach to human GWAS is the utilisation of model systems such as genetically diverse mouse panels to study natural genetic and phenotypic variation in a controlled environment. Here, we review mouse genetic reference panels and the opportunities they provide for the study of cardiometabolic diseases and related traits. We discuss how the post-GWAS era has prompted a shift in focus from discovery of novel genetic variants to understanding gene function. Finally, we highlight key advantages and challenges of integrating complementary genetic and multi-omics data from human and mouse populations to advance biological discovery.


Asunto(s)
Enfermedades Cardiovasculares , Estudio de Asociación del Genoma Completo , Animales , Humanos , Ratones , Enfermedades Cardiovasculares/genética , Predisposición Genética a la Enfermedad , Obesidad/genética , Fenotipo , Factores de Riesgo
4.
Nat Rev Cardiol ; 19(11): 765-777, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35577952

RESUMEN

Cardiovascular disease remains the leading cause of death worldwide. Cardiovascular research has therefore never been more crucial. Cardiovascular researchers must be provided with a research environment that enables them to perform at their highest level, maximizing their opportunities to work effectively with key stakeholders to address this global issue. At present, cardiovascular researchers face a range of challenges and barriers, including a decline in funding, job insecurity and a lack of diversity at senior leadership levels. Indeed, many cardiovascular researchers, particularly women, have considered leaving the sector, highlighting a crucial need to develop strategies to support and retain researchers working in the cardiovascular field. In this Roadmap article, we present solutions to problems relevant to cardiovascular researchers worldwide that are broadly classified across three key areas: capacity building, research funding and fostering diversity and equity. This Roadmap provides opportunities for research institutions, as well as governments and funding bodies, to implement changes from policy to practice, to address the most important factors restricting the career progression of cardiovascular researchers.


Asunto(s)
Políticas , Investigadores , Femenino , Humanos
5.
Front Physiol ; 13: 841278, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35309067

RESUMEN

Ether lipids are a unique class of glycero- and glycerophospho-lipid that carry an ether or vinyl ether linked fatty alcohol at the sn-1 position of the glycerol backbone. These specialised lipids are important endogenous anti-oxidants with additional roles in regulating membrane fluidity and dynamics, intracellular signalling, immunomodulation and cholesterol metabolism. Lipidomic profiling of human population cohorts has identified new associations between reduced circulatory plasmalogen levels, an abundant and biologically active sub-class of ether lipids, with obesity and body-mass index. These findings align with the growing body of work exploring novel roles for ether lipids within adipose tissue. In this regard, ether lipids have now been linked to facilitating lipid droplet formation, regulating thermogenesis and mediating beiging of white adipose tissue in early life. This review will assess recent findings in both population studies and studies using cell and animal models to delineate the functional and protective roles of ether lipids in the setting of obesity. We will also discuss the therapeutic potential of ether lipid supplementation to attenuate diet-induced obesity.

6.
Front Physiol ; 13: 837001, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35283789

RESUMEN

Adipose tissue is comprised of a heterogeneous population of cells that co-operate to perform diverse physiological roles including endocrine-related functions. The endocrine role of adipose tissue enables it to communicate nutritional and health cues to other organs, such as the liver, muscle, and brain, in order to regulate appetite and whole body metabolism. Adipose tissue dysfunction, which is often observed in obesity, is associated with changes in the adipose secretome, which can subsequently contribute to disease pathology. Indeed, secreted bioactive factors released from adipose tissue contribute to metabolic homeostasis and likely play a causal role in disease; however, what constitutes the entirety of the adipose tissue secretome is still poorly understood. Recent advances in nanotechnology have advanced this field substantially and have led to the identification of small, secreted particles known as extracellular vesicles (EVs). These small nano-sized lipid envelopes are released by most cell types and are capable of systemically delivering bioactive molecules, such as nucleic acids, proteins, and lipids. EVs interact with target cells to deliver specific cargo that can then elicit effects in various tissues throughout the body. Adipose tissue has recently been shown to secrete EVs that can communicate with the periphery to maintain metabolic homeostasis, or under certain pathological conditions, drive disease. In this review, we discuss the current landscape of adipose tissue-derived EVs, with a focus on their role in the regulation of metabolic homeostasis and disease pathology.

7.
Front Physiol ; 13: 839471, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35295579

RESUMEN

Synthetic oligonucleotide technologies are DNA or RNA based molecular compounds that are utilized to disrupt gene transcription or translation in target tissues or cells. Optimally, oligonucleotides are 10-30 base pairs in length, and mediate target gene suppression through directed sequence homology with messenger RNA (mRNA), leading to mRNA degradation. Examples of specific oligonucleotide technologies include antisense oligonucleotides (ASO), short hairpin RNAs (shRNA), and small interfering RNAs (siRNA). In vitro and in vivo studies that model obesity related disorders have demonstrated that oligonucleotide technologies can be implemented to improve the metabolism of cells and tissues, exemplified by improvements in fat utilization and hepatic insulin signaling, respectively. Oligonucleotide therapy has also been associated with reductions in lipid accumulation in both the liver and adipose tissue in models of diet-induced obesity. Recent advances in oligonucleotide technologies include the addition of chemical modifications such as N-acetylgalactosamine (GalNAc) conjugates that have been successful at achieving affinity for the liver, in turn improving specificity, and thus reducing off target effects. However, some challenges are still yet to be overcome relating to hepatic injury and off-target effects that have been reported with some compounds, including ASOs. In summary, oligonucleotide-based therapies are an effective tool to elucidate mechanistic insights into metabolic pathways and provide an attractive avenue for translational research into the clinic.

8.
Clin Sci (Lond) ; 135(24): 2691-2708, 2021 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-34908104

RESUMEN

The escalating prevalence of individuals becoming overweight and obese is a rapidly rising global health problem, placing an enormous burden on health and economic systems worldwide. Whilst obesity has well described lifestyle drivers, there is also a significant and poorly understood component that is regulated by genetics. Furthermore, there is clear evidence for sexual dimorphism in obesity, where overall risk, degree, subtype and potential complications arising from obesity all differ between males and females. The molecular mechanisms that dictate these sex differences remain mostly uncharacterised. Many studies have demonstrated that this dimorphism is unable to be solely explained by changes in hormones and their nuclear receptors alone, and instead manifests from coordinated and highly regulated gene networks, both during development and throughout life. As we acquire more knowledge in this area from approaches such as large-scale genomic association studies, the more we appreciate the true complexity and heterogeneity of obesity. Nevertheless, over the past two decades, researchers have made enormous progress in this field, and some consistent and robust mechanisms continue to be established. In this review, we will discuss some of the proposed mechanisms underlying sexual dimorphism in obesity, and discuss some of the key regulators that influence this phenomenon.


Asunto(s)
Tejido Adiposo Blanco/fisiopatología , Obesidad/genética , Caracteres Sexuales , Tejido Adiposo Blanco/metabolismo , Femenino , Humanos , Masculino , Obesidad/fisiopatología
10.
Nat Metab ; 3(11): 1476-1483, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34750571

RESUMEN

Cardiometabolic diseases are frequently polygenic in architecture, comprising a large number of risk alleles with small effects spread across the genome1-3. Polygenic scores (PGS) aggregate these into a metric representing an individual's genetic predisposition to disease. PGS have shown promise for early risk prediction4-7 and there is an open question as to whether PGS can also be used to understand disease biology8. Here, we demonstrate that cardiometabolic disease PGS can be used to elucidate the proteins underlying disease pathogenesis. In 3,087 healthy individuals, we found that PGS for coronary artery disease, type 2 diabetes, chronic kidney disease and ischaemic stroke are associated with the levels of 49 plasma proteins. Associations were polygenic in architecture, largely independent of cis and trans protein quantitative trait loci and present for proteins without quantitative trait loci. Over a follow-up of 7.7 years, 28 of these proteins associated with future myocardial infarction or type 2 diabetes events, 16 of which were mediators between polygenic risk and incident disease. Twelve of these were druggable targets with therapeutic potential. Our results demonstrate the potential for PGS to uncover causal disease biology and targets with therapeutic potential, including those that may be missed by approaches utilizing information at a single locus.


Asunto(s)
Proteínas Sanguíneas , Cardiopatías/etiología , Cardiopatías/metabolismo , Enfermedades Metabólicas/etiología , Enfermedades Metabólicas/metabolismo , Herencia Multifactorial , Proteoma , Adulto , Biomarcadores , Manejo de la Enfermedad , Susceptibilidad a Enfermedades , Inglaterra/epidemiología , Femenino , Predisposición Genética a la Enfermedad , Cardiopatías/diagnóstico , Cardiopatías/epidemiología , Humanos , Masculino , Enfermedades Metabólicas/diagnóstico , Enfermedades Metabólicas/epidemiología , Persona de Mediana Edad , Vigilancia en Salud Pública , Adulto Joven
11.
Redox Biol ; 47: 102135, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34598016

RESUMEN

Metabolic conditions such as obesity, insulin resistance and glucose intolerance are frequently associated with impairments in skeletal muscle function and metabolism. This is often linked to dysregulation of homeostatic pathways including an increase in reactive oxygen species (ROS) and oxidative stress. One of the main sites of ROS production is the mitochondria, where the flux of substrates through the electron transport chain (ETC) can result in the generation of oxygen free radicals. Fortunately, several mechanisms exist to buffer bursts of intracellular ROS and peroxide production, including the enzymes Catalase, Glutathione Peroxidase and Superoxide Dismutase (SOD). Of the latter, there are two intracellular isoforms; SOD1 which is mostly cytoplasmic, and SOD2 which is found exclusively in the mitochondria. Developmental and chronic loss of these enzymes has been linked to disease in several studies, however the temporal effects of these disturbances remain largely unexplored. Here, we induced a post-developmental (8-week old mice) deletion of SOD2 in skeletal muscle (SOD2-iMKO) and demonstrate that 16 weeks of SOD2 deletion leads to no major impairment in whole body metabolism, despite these mice displaying alterations in aspects of mitochondrial abundance and voluntary ambulatory movement. This is likely partly explained by the suggestive data that a compensatory response may exist from other redox enzymes, including catalase and glutathione peroxidases. Nevertheless, we demonstrated that inducible SOD2 deletion impacts on specific aspects of muscle lipid metabolism, including the abundance of phospholipids and phosphatidic acid (PA), the latter being a key intermediate in several cellular signaling pathways. Thus, our findings suggest that post-developmental deletion of SOD2 induces a more subtle phenotype than previous embryonic models have shown, allowing us to highlight a previously unrecognized link between SOD2, mitochondrial function and bioactive lipid species including PA.


Asunto(s)
Músculo Esquelético , Superóxido Dismutasa , Animales , Ratones , Mitocondrias/genética , Mitocondrias/metabolismo , Músculo Esquelético/metabolismo , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo
12.
JCI Insight ; 6(17)2021 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-34494556

RESUMEN

Lipin 1 regulates cellular lipid homeostasis through roles in glycerolipid synthesis (through phosphatidic acid phosphatase activity) and transcriptional coactivation. Lipin 1-deficient individuals exhibit episodic disease symptoms that are triggered by metabolic stress, such as stress caused by prolonged fasting. We sought to identify critical lipin 1 activities during fasting. We determined that lipin 1 deficiency induces widespread alternative mRNA splicing in liver during fasting, much of which is normalized by refeeding. The role of lipin 1 in mRNA splicing was largely independent of its enzymatic function. We identified interactions between lipin 1 and spliceosome proteins, as well as a requirement for lipin 1 to maintain homeostatic levels of spliceosome small nuclear RNAs and specific RNA splicing factors. In fasted Lpin1-/- liver, we identified a correspondence between alternative splicing of phospholipid biosynthetic enzymes and dysregulated phospholipid levels; splicing patterns and phospholipid levels were partly normalized by feeding. Thus, lipin 1 influences hepatic lipid metabolism through mRNA splicing, as well as through enzymatic and transcriptional activities, and fasting exacerbates the deleterious effects of lipin 1 deficiency on metabolic homeostasis.


Asunto(s)
Adaptación Fisiológica/genética , Ayuno/fisiología , Metabolismo de los Lípidos/genética , Hígado/metabolismo , ARN Mensajero/genética , Empalme Alternativo , Animales , Células Cultivadas , Femenino , Humanos , Hígado/citología , Masculino , Ratones , Ratones Endogámicos BALB C , Modelos Animales , Fosfatidato Fosfatasa , Empalme del ARN , Factores de Transcripción/genética
13.
Arterioscler Thromb Vasc Biol ; 41(9): 2494-2508, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34233476

RESUMEN

Objective: Low HDL-C (high-density lipoprotein cholesterol) is the most frequent dyslipidemia in Mexicans, but few studies have examined the underlying genetic basis. Our purpose was to identify genetic variants associated with HDL-C levels and cardiovascular risk in the Mexican population. Approach and Results: A genome-wide association studies for HDL-C levels in 2335 Mexicans, identified four loci associated with genome-wide significance: CETP, ABCA1, LIPC, and SIDT2. The SIDT2 missense Val636Ile variant was associated with HDL-C levels and was replicated in 3 independent cohorts (P=5.9×10−18 in the conjoint analysis). The SIDT2/Val636Ile variant is more frequent in Native American and derived populations than in other ethnic groups. This variant was also associated with increased ApoA1 and glycerophospholipid serum levels, decreased LDL-C (low-density lipoprotein cholesterol) and ApoB levels, and a lower risk of premature CAD. Because SIDT2 was previously identified as a protein involved in sterol transport, we tested whether the SIDT2/Ile636 protein affected this function using an in vitro site-directed mutagenesis approach. The SIDT2/Ile636 protein showed increased uptake of the cholesterol analog dehydroergosterol, suggesting this variant affects function. Finally, liver transcriptome data from humans and the Hybrid Mouse Diversity Panel are consistent with the involvement of SIDT2 in lipid and lipoprotein metabolism. Conclusions: This is the first genome-wide association study for HDL-C levels seeking associations with coronary artery disease in the Mexican population. Our findings provide new insight into the genetic architecture of HDL-C and highlight SIDT2 as a new player in cholesterol and lipoprotein metabolism in humans.


Asunto(s)
HDL-Colesterol/sangre , Enfermedad de la Arteria Coronaria/genética , Hiperlipoproteinemia Tipo II/genética , Proteínas de Transporte de Nucleótidos/genética , Polimorfismo de Nucleótido Simple , Adulto , Edad de Inicio , Animales , Biomarcadores/sangre , Estudios de Casos y Controles , Niño , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/diagnóstico , Enfermedad de la Arteria Coronaria/epidemiología , Modelos Animales de Enfermedad , Femenino , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Células HEK293 , Factores de Riesgo de Enfermedad Cardiaca , Humanos , Hiperlipoproteinemia Tipo II/sangre , Hiperlipoproteinemia Tipo II/diagnóstico , Hiperlipoproteinemia Tipo II/epidemiología , Masculino , Análisis de la Aleatorización Mendeliana , México/epidemiología , Ratones , Persona de Mediana Edad , Proteínas de Transporte de Nucleótidos/metabolismo , Fenotipo , Medición de Riesgo
14.
Cell Metab ; 33(8): 1671-1684.e4, 2021 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-34270928

RESUMEN

FXR agonists are used to treat non-alcoholic fatty liver disease (NAFLD), in part because they reduce hepatic lipids. Here, we show that FXR activation with the FXR agonist GSK2324 controls hepatic lipids via reduced absorption and selective decreases in fatty acid synthesis. Using comprehensive lipidomic analyses, we show that FXR activation in mice or humans specifically reduces hepatic levels of mono- and polyunsaturated fatty acids (MUFA and PUFA). Decreases in MUFA are due to FXR-dependent repression of Scd1, Dgat2, and Lpin1 expression, which is independent of SHP and SREBP1c. FXR-dependent decreases in PUFAs are mediated by decreases in lipid absorption. Replenishing bile acids in the diet prevented decreased lipid absorption in GSK2324-treated mice, suggesting that FXR reduces absorption via decreased bile acids. We used tissue-specific FXR KO mice to show that hepatic FXR controls lipogenic genes, whereas intestinal FXR controls lipid absorption. Together, our studies establish two distinct pathways by which FXR regulates hepatic lipids.


Asunto(s)
Ácidos y Sales Biliares , Enfermedad del Hígado Graso no Alcohólico , Animales , Bilis , Ácidos y Sales Biliares/metabolismo , Humanos , Lípidos , Hígado/metabolismo , Ratones , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/prevención & control , Fosfatidato Fosfatasa/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo
15.
Mol Metab ; 53: 101292, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34246805

RESUMEN

OBJECTIVE: CRISPR/Cas9 technology has revolutionized gene editing and fast tracked our capacity to manipulate genes of interest for the benefit of both research and therapeutic applications. Whilst many advances have, and continue to be made in this area, perhaps the most utilized technology to date has been the generation of knockout cells, tissues and animals. The advantages of this technology are many fold, however some questions still remain regarding the effects that long term expression of foreign proteins such as Cas9, have on mammalian cell function. Several studies have proposed that chronic overexpression of Cas9, with or without its accompanying guide RNAs, may have deleterious effects on cell function and health. This is of particular concern when applying this technology in vivo, where chronic expression of Cas9 in tissues of interest may promote disease-like phenotypes and thus confound the investigation of the effects of the gene of interest. Although these concerns remain valid, no study to our knowledge has yet to demonstrate this directly. METHODS: In this study we used the lox-stop-lox (LSL) spCas9 ROSA26 transgenic (Tg) mouse line to generate four tissue-specific Cas9-Tg models that express Cas9 in the heart, liver, skeletal muscle or adipose tissue. We performed comprehensive phenotyping of these mice up to 20-weeks of age and subsequently performed molecular analysis of their organs. RESULTS: We demonstrate that Cas9 expression in these tissues had no detrimental effect on whole body health of the animals, nor did it induce any tissue-specific effects on whole body energy metabolism, liver health, inflammation, fibrosis, heart function or muscle mass. CONCLUSIONS: Our data suggests that these models are suitable for studying the tissue specific effects of gene deletion using the LSL-Cas9-Tg model, and that phenotypes observed utilizing these models can be confidently interpreted as being gene specific, and not confounded by the chronic overexpression of Cas9.


Asunto(s)
Proteína 9 Asociada a CRISPR/genética , Animales , Sistemas CRISPR-Cas/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Fenotipo
16.
Metabolites ; 11(6)2021 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-34070445

RESUMEN

Statins are the first-line lipid-lowering therapy for reducing cardiovascular disease (CVD) risk. A plasma lipid ratio of two phospholipids, PI(36:2) and PC(18:0_20:4), was previously identified to explain 58% of the relative CVD risk reduction associated with pravastatin, independent of a change in low-density lipoprotein-cholesterol. This ratio may be a potential biomarker for the treatment effect of statins; however, the underlying mechanisms linking this ratio to CVD risk remain unclear. In this study, we investigated the effect of altered cholesterol conditions on the lipidome of cultured human liver cells (Hep3B). Hep3B cells were treated with simvastatin (5 µM), cyclodextrin (20 mg/mL) or cholesterol-loaded cyclodextrin (20 mg/mL) for 48 hours and their lipidomes were examined. Induction of a low-cholesterol environment via simvastatin or cyclodextrin was associated with elevated levels of lipids containing arachidonic acid and decreases in phosphatidylinositol species and the PI(36:2)/PC(18:0_20:4) ratio. Conversely, increasing cholesterol levels via cholesterol-loaded cyclodextrin resulted in reciprocal regulation of these lipid parameters. Expression of genes involved in cholesterol and fatty acid synthesis supported the lipidomics data. These findings demonstrate that the PI(36:2)/PC(18:0_20:4) ratio responds to changes in intracellular cholesterol abundance per se, likely through a flux of the n-6 fatty acid pathway and altered phosphatidylinositol synthesis. These findings support this ratio as a potential marker for CVD risk reduction and may be useful in monitoring treatment response.

17.
iScience ; 24(6): 102537, 2021 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-34142046

RESUMEN

Long non-coding RNAs (lncRNAs) have been demonstrated to influence numerous biological processes, being strongly implicated in the maintenance and physiological function of various tissues including the heart. The lncRNA OIP5-AS1 (1700020I14Rik/Cyrano) has been studied in several settings; however its role in cardiac pathologies remains mostly uncharacterized. Using a series of in vitro and ex vivo methods, we demonstrate that OIP5-AS1 is regulated during cardiac development in rodent and human models and in disease settings in mice. Using CRISPR, we engineered a global OIP5-AS1 knockout (KO) mouse and demonstrated that female KO mice develop exacerbated heart failure following cardiac pressure overload (transverse aortic constriction [TAC]) but male mice do not. RNA-sequencing of wild-type and KO hearts suggest that OIP5-AS1 regulates pathways that impact mitochondrial function. Thus, these findings highlight OIP5-AS1 as a gene of interest in sex-specific differences in mitochondrial function and development of heart failure.

18.
Nat Commun ; 12(1): 74, 2021 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-33397965

RESUMEN

The effective storage of lipids in white adipose tissue (WAT) critically impacts whole body energy homeostasis. Many genes have been implicated in WAT lipid metabolism, including tripartite motif containing 28 (Trim28), a gene proposed to primarily influence adiposity via epigenetic mechanisms in embryonic development. However, in the current study we demonstrate that mice with deletion of Trim28 specifically in committed adipocytes, also develop obesity similar to global Trim28 deletion models, highlighting a post-developmental role for Trim28. These effects were exacerbated in female mice, contributing to the growing notion that Trim28 is a sex-specific regulator of obesity. Mechanistically, this phenotype involves alterations in lipolysis and triglyceride metabolism, explained in part by loss of Klf14 expression, a gene previously demonstrated to modulate adipocyte size and body composition in a sex-specific manner. Thus, these findings provide evidence that Trim28 is a bona fide, sex specific regulator of post-developmental adiposity and WAT function.


Asunto(s)
Adipocitos/metabolismo , Eliminación de Gen , Glucosa/metabolismo , Obesidad/patología , Proteína 28 que Contiene Motivos Tripartito/genética , Células 3T3-L1 , Tejido Adiposo Blanco/metabolismo , Adiposidad , Animales , Peso Corporal , Dieta , Dieta Alta en Grasa , Metabolismo Energético , Femenino , Redes Reguladoras de Genes , Metabolismo de los Lípidos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Obesidad/genética , Fenotipo , Triglicéridos/metabolismo , Proteína 28 que Contiene Motivos Tripartito/deficiencia
19.
ACS Pharmacol Transl Sci ; 3(4): 773-779, 2020 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-32832876

RESUMEN

Inequities for women exist across many leverage points of an academic career in science, technology, engineering, mathematics, and medicine (STEMM) disciplines, ranging from poorer success rates at promotion, reduced grant success, and a lower likelihood of invited conference presentations, to a propensity to undertake the lion's share of academic service roles. Moreover, an almost intractable salary gap exists, along with a stark under-representation of women in senior scientific leadership roles, widespread throughout the United States, United Kingdom, Europe, and Australia. Numerous factors have been put forward as contributors to this disparity, including the notions that these inequities are a result of a pipeline issue and that women are less qualified or have less experience than men, implicit bias, a lack of flexibility in the work place, a lack of role models, the use of biased measures of success for promotion, and the lack of equitable parental leave programs. In this viewpoint, we address factors shown to contribute to the lack of women in leadership roles. Specifically, we look at systemic barriers, parental and carer leave, and domestic barriers, and we present solutions to address these barriers across an individual's professional and personal life. For women to achieve equity in senior scientific leadership roles, we believe that barriers across all facets of life need to be addressed and that the important contributions that women make and have made to STEMM need to be recognized.

20.
Heart Lung Circ ; 29(11): 1588-1595, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32839116

RESUMEN

BACKGROUND: Cardiovascular disease is the leading cause of death in Australia. Investment in research solutions has been demonstrated to yield health and a 9.8-fold return economic benefit. The sector, however, is severely challenged with success rates of traditional peer-reviewed funding in decline. Here, we aimed to understand the perceived challenges faced by the cardiovascular workforce in Australia prior to the COVID-19 pandemic. METHODS: We used an online survey distributed across Australian cardiovascular societies/councils, universities and research institutes over a period of 6 months during 2019, with 548 completed responses. Inclusion criteria included being an Australian resident or an Australian citizen who lived overseas, and a current or past student or employee in the field of cardiovascular research. RESULTS: The mean age of respondents was 42±13 years, 47% were male, 85% had a full-time position, and 40% were a group leader or laboratory head. Twenty-three per cent (23%) had permanent employment, and 82% of full-time workers regularly worked >40 hours/week. Sixty-eight per cent (68%) said they had previously considered leaving the cardiovascular research sector. If their position could not be funded in the next few years, a staggering 91% of respondents would leave the sector. Compared to PhD- and age-matched men, women were less likely to be a laboratory head and to feel they had a long-term career path as a cardiovascular researcher, while more women were unsure about future employment and had considered leaving the sector (all p<0.05). Greater job security (76%) and government and philanthropic investment in cardiovascular research (72%) were highlighted by responders as the main changes to current practices that would encourage them to stay. CONCLUSION: Strategic solutions, such as diversification of career pathways and funding sources, and moving from a competitive to a collaborative culture, need to be a priority to decrease reliance on government funding and allow cardiovascular researchers to thrive.


Asunto(s)
Investigación Biomédica , Enfermedades Cardiovasculares , Infecciones por Coronavirus/epidemiología , Administración Financiera , Neumonía Viral/epidemiología , Investigadores , Apoyo a la Investigación como Asunto , Recursos Humanos , Adulto , Australia , Betacoronavirus , Investigación Biomédica/economía , Investigación Biomédica/organización & administración , Investigación Biomédica/tendencias , COVID-19 , Empleo/economía , Empleo/psicología , Femenino , Administración Financiera/métodos , Administración Financiera/organización & administración , Administración Financiera/estadística & datos numéricos , Financiación Gubernamental , Humanos , Masculino , Cultura Organizacional , Pandemias , Técnicas de Planificación , Investigadores/economía , Investigadores/psicología , Investigadores/estadística & datos numéricos , Apoyo a la Investigación como Asunto/organización & administración , Apoyo a la Investigación como Asunto/tendencias , SARS-CoV-2 , Encuestas y Cuestionarios , Recursos Humanos/estadística & datos numéricos
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