Laboratoire de recherche en cardiovasculaire, métabolisme, diabétologie et nutrition

The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles ("MISEV") guidelines for the field in 2014. We now update these "MISEV2014" guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points.

This review represents an update of the nomenclature system for the UDP glucuronosyltransferase gene superfamily, which is based on divergent evolution. Since the previous review in 1991, sequences of many related UDP glycosyltransferases from lower organisms have appeared in the database, which expand our database considerably. At latest count, in animals, yeast, plants and bacteria there are 110 distinct cDNAs/genes whose protein products all contain a characteristic 'signature sequence' and, thus, are regarded as members of the same superfamily. Comparison of a relatedness tree of proteins leads to the definition of 33 families. It should be emphasized that at least six cloned UDP-GlcNAc N-acetylglucosaminyltransferases are not sufficiently homologous to be included as members of this superfamily and may represent an example of convergent evolution. For naming each gene, it is recommended that the root symbol UGT for human (Ugt for mouse and Drosophila), denoting 'UDP glycosyltransferase,' be followed by an Arabic number representing the family, a letter designating the subfamily, and an Arabic numeral denoting the individual gene within the family or subfamily, e.g. 'human UGT2B4' and 'mouse Ugt2b5'. We recommend the name 'UDP glycosyltransferase' because many of the proteins do not preferentially use UDP glucuronic acid, or their nucleotide sugar preference is unknown. Whereas the gene is italicized, the corresponding cDNA, transcript, protein and enzyme activity should be written with upper-case letters and without italics, e.g. 'human or mouse UGT1A1.' The UGT1 gene (spanning > 500 kb) contains at least 12 promoters/first exons, which can be spliced and joined with common exons 2 through 5, leading to different N-terminal halves but identical C-terminal halves of the gene products; in this scheme each first exon is regarded as a distinct gene (e.g. UGT1A1, UGT1A2, ... UGT1A12). When an orthologous gene between species cannot be identified with certainty, as occurs in the UGT2B subfamily, sequential naming of the genes is being carried out chronologically as they become characterized. We suggest that the Human Gene Nomenclature Guidelines (http://www.gene.acl.ac.uk/nomenclature/guidelines.html++ +) be used for all species other than the mouse and Drosophila. Thirty published human UGT1A1 mutant alleles responsible for clinical hyperbilirubinemias are listed herein, and given numbers following an asterisk (e.g. UGT1A1*30) consistent with the Human Gene Nomenclature Guidelines. It is anticipated that this UGT gene nomenclature system will require updating on a regular basis.

Recent advances in human genetics, together with a large body of epidemiologic, preclinical, and clinical trial results, provide strong support for a causal association between triglycerides (TG), TG-rich lipoproteins (TRL), and TRL remnants, and increased risk of myocardial infarction, ischaemic stroke, and aortic valve stenosis. These data also indicate that TRL and their remnants may contribute significantly to residual cardiovascular risk in patients on optimized low-density lipoprotein (LDL)-lowering therapy. This statement critically appraises current understanding of the structure, function, and metabolism of TRL, and their pathophysiological role in atherosclerotic cardiovascular disease (ASCVD). Key points are (i) a working definition of normo- and hypertriglyceridaemic states and their relation to risk of ASCVD, (ii) a conceptual framework for the generation of remnants due to dysregulation of TRL production, lipolysis, and remodelling, as well as clearance of remnant lipoproteins from the circulation, (iii) the pleiotropic proatherogenic actions of TRL and remnants at the arterial wall, (iv) challenges in defining, quantitating, and assessing the atherogenic properties of remnant particles, and (v) exploration of the relative atherogenicity of TRL and remnants compared to LDL. Assessment of these issues provides a foundation for evaluating approaches to effectively reduce levels of TRL and remnants by targeting either production, lipolysis, or hepatic clearance, or a combination of these mechanisms. This consensus statement updates current understanding in an integrated manner, thereby providing a platform for new therapeutic paradigms targeting TRL and their remnants, with the aim of reducing the risk of ASCVD.

Abstract Aims/hypothesis Coronavirus disease-2019 (COVID-19) is a life-threatening infection caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus. Diabetes has rapidly emerged as a major comorbidity for COVID-19 severity. However, the phenotypic characteristics of diabetes in COVID-19 patients are unknown. Methods We conducted a nationwide multicentre observational study in people with diabetes hospitalised for COVID-19 in 53 French centres in the period 10–31 March 2020. The primary outcome combined tracheal intubation for mechanical ventilation and/or death within 7 days of admission. Age- and sex-adjusted multivariable logistic regressions were performed to assess the prognostic value of clinical and biological features with the endpoint. ORs are reported for a 1 SD increase after standardisation. Results The current analysis focused on 1317 participants: 64.9% men, mean age 69.8 ± 13.0 years, median BMI 28.4 (25th–75th percentile: 25.0–32.7) kg/m 2 ; with a predominance of type 2 diabetes (88.5%). Microvascular and macrovascular diabetic complications were found in 46.8% and 40.8% of cases, respectively. The primary outcome was encountered in 29.0% (95% CI 26.6, 31.5) of participants, while 10.6% (9.0, 12.4) died and 18.0% (16.0, 20.2) were discharged on day 7. In univariate analysis, characteristics prior to admission significantly associated with the primary outcome were sex, BMI and previous treatment with renin–angiotensin–aldosterone system (RAAS) blockers, but not age, type of diabetes, HbA 1c , diabetic complications or glucose-lowering therapies. In multivariable analyses with covariates prior to admission, only BMI remained positively associated with the primary outcome (OR 1.28 [1.10, 1.47]). On admission, dyspnoea (OR 2.10 [1.31, 3.35]), as well as lymphocyte count (OR 0.67 [0.50, 0.88]), C-reactive protein (OR 1.93 [1.43, 2.59]) and AST (OR 2.23 [1.70, 2.93]) levels were independent predictors of the primary outcome. Finally, age (OR 2.48 [1.74, 3.53]), treated obstructive sleep apnoea (OR 2.80 [1.46, 5.38]), and microvascular (OR 2.14 [1.16, 3.94]) and macrovascular complications (OR 2.54 [1.44, 4.50]) were independently associated with the risk of death on day 7. Conclusions/interpretations In people with diabetes hospitalised for COVID-19, BMI, but not long-term glucose control, was positively and independently associated with tracheal intubation and/or death within 7 days. Trial registration clinicaltrials.gov NCT04324736.

Mitochondrial dysfunction in skeletal muscle has been implicated in the development of type 2 diabetes. However, whether these changes are a cause or a consequence of insulin resistance is not clear. We investigated the structure and function of muscle mitochondria during the development of insulin resistance and progression to diabetes in mice fed a high-fat, high-sucrose diet. Although 1 month of high-fat, high-sucrose diet feeding was sufficient to induce glucose intolerance, mice showed no evidence of mitochondrial dysfunction at this stage. However, an extended diet intervention induced a diabetic state in which we observed altered mitochondrial biogenesis, structure, and function in muscle tissue. We assessed the role of oxidative stress in the development of these mitochondrial abnormalities and found that diet-induced diabetic mice had an increase in ROS production in skeletal muscle. In addition, ROS production was associated with mitochondrial alterations in the muscle of hyperglycemic streptozotocin-treated mice, and normalization of glycemia or antioxidant treatment decreased muscle ROS production and restored mitochondrial integrity. Glucose- or lipid-induced ROS production resulted in mitochondrial alterations in muscle cells in vitro, and these effects were blocked by antioxidant treatment. These data suggest that mitochondrial alterations do not precede the onset of insulin resistance and result from increased ROS production in muscle in diet-induced diabetic mice.

Many treatments have been identified that confer robust cardioprotection in experimental animal models of acute ischemia and reperfusion injury. However, translation of these cardioprotective therapies into the clinical setting of acute myocardial infarction (AMI) for patient benefit has been disappointing. One important reason might be that AMI is multifactorial, causing cardiomyocyte death via multiple mechanisms, as well as affecting other cell types, including platelets, fibroblasts, endothelial and smooth muscle cells, and immune cells. Many cardioprotective strategies act through common end-effectors and may be suboptimal in patients with comorbidities. In this regard, emerging data suggest that optimal cardioprotection may require the combination of additive or synergistic multitarget therapies. This review will present an overview of the state of cardioprotection today and provide a roadmap for how we might progress towards successful clinical use of cardioprotective therapies following AMI, focusing on the rational combination of judiciously selected, multitarget therapies. This paper emerged as part of the discussions of the European Union (EU)-CARDIOPROTECTION Cooperation in Science and Technology (COST) Action, CA16225.

BACKGROUND: Obesity is a risk factor for impaired cardiac performance, particularly in women. Animal studies suggest that alterations in myocardial fatty acid metabolism and efficiency in obesity can cause decreased cardiac performance. In the present study, we tested the hypothesis that myocardial fatty acid metabolism and efficiency are abnormal in obese women. METHODS AND RESULTS: We studied 31 young women (body mass index [BMI] 19 to 52 kg/m2); 19 were obese (BMI >30 kg/m2). Myocardial oxygen consumption (MVO2) and fatty acid uptake (MFAUp), utilization (MFAU), and oxidation (MFAO) were quantified by positron emission tomography. Cardiac work was measured by echocardiography, and efficiency was calculated as work/MVO2. BMI correlated with MVO2 (r=0.58, P=0.0006), MFAUp (r=0.42, P<0.05), and efficiency (r=-0.40, P<0.05). Insulin resistance, quantified by the glucose area under the curve (AUC) during an oral glucose tolerance test, correlated with MFAUp (r=0.55, P<0.005), MFAU (r=0.62, P<0.001), and MFAO (r=0.58, P<0.005). A multivariate, stepwise regression analysis showed that BMI was the only independent predictor of MVO2 and efficiency (P=0.0005 and P<0.05, respectively). Glucose AUC was the only independent predictor of MFAUp, MFAU, and MFAO (P<0.05, <0.005, and <0.005, respectively). CONCLUSIONS: In young women, obesity is a significant predictor of increased MVO2 and decreased efficiency, and insulin resistance is a robust predictor of MFAUp, MFAU, and MFAO. This increase in fatty acid metabolism and decrease in efficiency is concordant with observations made in experimental models of obesity. These metabolic changes may play a role in the pathogenesis of decreased cardiac performance in obese women.

Patient engagement has become a major focus of health reform. However, there is limited evidence showing that increases in patient engagement are associated with improved health outcomes or lower costs. We examined the extent to which a single assessment of engagement, the Patient Activation Measure, was associated with health outcomes and costs over time, and whether changes in assessed activation were related to expected changes in outcomes and costs. We used data on adult primary care patients from a single large health care system where the Patient Activation Measure is routinely used. We found that results indicating higher activation in 2010 were associated with nine out of thirteen better health outcomes-including better clinical indicators, more healthy behaviors, and greater use of women's preventive screening tests-as well as with lower costs two years later. Changes in activation level were associated with changes in over half of the health outcomes examined, as well as costs, in the expected directions. These findings suggest that efforts to increase patient activation may help achieve key goals of health reform and that further research is warranted to examine whether the observed associations are causal.

Microbiota and infant development Malnutrition in children is a persistent challenge that is not always remedied by improvements in nutrition. This is because a characteristic community of gut microbes seems to mediate some of the pathology. Human gut microbes can be transplanted effectively into germ-free mice to recapitulate their associated phenotypes. Using this model, Blanton et al. found that the microbiota of healthy children relieved the harmful effects on growth caused by the microbiota of malnourished children. In infant mammals, chronic undernutrition results in growth hormone resistance and stunting. In mice, Schwarzer et al. showed that strains of Lactobacillus plantarum in the gut microbiota sustained growth hormone activity via signaling pathways in the liver, thus overcoming growth hormone resistance. Together these studies reveal that specific beneficial microbes could potentially be exploited to resolve undernutrition syndromes. Science , this issue p. 10.1126/science.aad3311 , p. 854

BACKGROUND: Recent research shows that sedentary behaviour is associated with adverse cardio-metabolic consequences even among those considered sufficiently physically active. In order to successfully develop interventions to address this unhealthy behaviour, factors that influence sedentariness need to be identified and fully understood. The aim of this review is to identify individual, social, environmental, and policy-related determinants or correlates of sedentary behaviours among adults aged 18-65 years. METHODS: PubMed, Embase, CINAHL, PsycINFO and Web of Science were searched for articles published between January 2000 and September 2015. The search strategy was based on four key elements and their synonyms: (a) sedentary behaviour (b) correlates (c) types of sedentary behaviours (d) types of correlates. Articles were included if information relating to sedentary behaviour in adults (18-65 years) was reported. Studies on samples selected by disease were excluded. The full protocol is available from PROSPERO (PROSPERO 2014:CRD42014009823). RESULTS: 74 original studies were identified out of 4041: 71 observational, two qualitative and one experimental study. Sedentary behaviour was primarily measured as self-reported screen leisure time and total sitting time. In 15 studies, objectively measured total sedentary time was reported: accelerometry (n = 14) and heart rate (n = 1). Individual level factors such as age, physical activity levels, body mass index, socio-economic status and mood were all significantly correlated with sedentariness. A trend towards increased amounts of leisure screen time was identified in those married or cohabiting while having children resulted in less total sitting time. Several environmental correlates were identified including proximity of green space, neighbourhood walkability and safety and weather. CONCLUSIONS: Results provide further evidence relating to several already recognised individual level factors and preliminary evidence relating to social and environmental factors that should be further investigated. Most studies relied upon cross-sectional design limiting causal inference and the heterogeneity of the sedentary measures prevented direct comparison of findings. Future research necessitates longitudinal study designs, exploration of policy-related factors, further exploration of environmental factors, analysis of inter-relationships between identified factors and better classification of sedentary behaviour domains.

Adverse experiences in childhood and adolescence, defined as subjectively perceived threats to the safety or security of the child's bodily integrity, family, or social structures, are known to be associated with cardiometabolic outcomes over the life course into adulthood. This American Heart Association scientific statement reviews the scientific literature on the influence of childhood adversity on cardiometabolic outcomes that constitute the greatest public health burden in the United States, including obesity, hypertension, type 2 diabetes mellitus, and cardiovascular disease. This statement also conceptually outlines pathways linking adversity to cardiometabolic health, identifies evidence gaps, and provides suggestions for future research to inform practice and policy. We note that, despite a lack of objective agreement on what subjectively qualifies as exposure to childhood adversity and a dearth of prospective studies, substantial evidence documents an association between childhood adversity and cardiometabolic outcomes across the life course. Future studies that focus on mechanisms, resiliency, and vulnerability factors would further strengthen the evidence and provide much-needed information on targets for effective interventions. Given that childhood adversities affect cardiometabolic health and multiple health domains across the life course, interventions that ameliorate these initial upstream exposures may be more appropriate than interventions remediating downstream cardiovascular disease risk factor effects later in life.

The effect of aging on the number of non-growing follicles (NGF) and early-growing follicles (EGF) was studied in humans through use of a database obtained by pooling two subsets of ovarian pairs (2 x 43 pairs) collected in two distinct populations. A previously suggested model of exponential regression of NGF counts in relation to the subject's age was tested but did not adequately fit the observed data points. This lack of fit is attributable mainly to the existence of a significant relation between a woman's age and the corresponding NGF count decay rate. Consequently, various regression models were tested. Two different periods of decay rate were observed for each population of small follicles. The first corresponds to younger ages with a decay rate that is slow for both types of follicles, although faster for NGF than for EGF. The second period corresponds to older ages with an accelerated decay rate that appears similar for NGF and EGF. The changing points were found at 38.0 +/- 2.4 and 39.0 +/- 1.9 yr (mean +/- SD) for NGF and EGF, respectively. Extrapolation of the fitted model suggested the presence of approximately 402,000 healthy NGF per ovary at birth and a total exhaustion of the follicular stock at around 74 yr of age. These results support the view that depletion of the NGF pool is caused mainly by atresia in younger women but mainly by entrance of NGF into the growing pool in older women. The mechanisms triggering accelerated entrance into the growth phase of NGF are discussed in relation to the previously reported increase in FSH plasma levels that starts in the late thirties, approximately, and precedes the menopausal period by several years.

OBJECTIVE: Through a literature review, we investigated the geographic information systems (GIS) methods used to define the food environment and the types of spatial measurements they generate. DESIGN: Review study. SETTING: Searches were conducted in health science databases, including Medline/Pubmed, PsycINFO, Francis and GeoBase. We included studies using GIS-based measures of the food environment published up to 1 June 2008. RESULTS: Twenty-nine papers were included. Two different spatial approaches were identified. The density approach quantifies the availability of food outlets using the buffer method, kernel density estimation or spatial clustering. The proximity approach assesses the distance to food outlets by measuring distances or travel times. GIS network analysis tools enable the modelling of travel time between referent addresses (home) and food outlets for a given transportation network and mode, and the assumption of travel routing behaviours. Numerous studies combined both approaches to compare food outlet spatial accessibility between different types of neighbourhoods or to investigate relationships between characteristics of the food environment and individual food behaviour. CONCLUSIONS: GIS methods provide new approaches for assessing the food environment by modelling spatial accessibility to food outlets. On the basis of the available literature, it appears that only some GIS methods have been used, while other GIS methods combining availability and proximity, such as spatial interaction models, have not yet been applied to this field. Future research would also benefit from a combination of GIS methods with survey approaches to describe both spatial and social food outlet accessibility as important determinants of individual food behaviours.

Blood viscosity is an important determinant of local flow characteristics, which exhibits shear thinning behavior: it decreases exponentially with increasing shear rates. Both hematocrit and plasma viscosity influence blood viscosity. The shear thinning property of blood is mainly attributed to red blood cell (RBC) rheological properties. RBC aggregation occurs at low shear rates, and increases blood viscosity and depends on both cellular (RBC aggregability) and plasma factors. Blood flow in the microcirculation is highly dependent on the ability of RBC to deform, but RBC deformability also affects blood flow in the macrocirculation since a loss of deformability causes a rise in blood viscosity. Indeed, any changes in one or several of these parameters may affect blood viscosity differently. Poiseuille's Law predicts that any increase in blood viscosity should cause a rise in vascular resistance. However, blood viscosity, through its effects on wall shear stress, is a key modulator of nitric oxide (NO) production by the endothelial NO-synthase. Indeed, any increase in blood viscosity should promote vasodilation. This is the case in healthy individuals when vascular function is intact and able to adapt to blood rheological strains. However, in sickle cell disease (SCD) vascular function is impaired. In this context, any increase in blood viscosity can promote vaso-occlusive like events. We previously showed that sickle cell patients with high blood viscosity usually have more frequent vaso-occlusive crises than those with low blood viscosity. However, while the deformability of RBC decreases during acute vaso-occlusive events in SCD, patients with the highest RBC deformability at steady-state have a higher risk of developing frequent painful vaso-occlusive crises. This paradox seems to be due to the fact that in SCD RBC with the highest deformability are also the most adherent, which would trigger vaso-occlusion. While acute, intense exercise may increase blood viscosity in healthy individuals, recent works conducted in sickle cell patients have shown that light cycling exercise did not cause dramatic changes in blood rheology. Moreover, regular physical exercise has been shown to decrease blood viscosity in sickle cell mice, which could be beneficial for adequate blood flow and tissue perfusion.

Exosomes are nanoparticles (∼100 nm diameter) released from cells, which can transfer small RNAs and mRNA via the extracellular environment to cells at distant sites. We hypothesised that exosomes or the slightly larger microvesicles (100-300 nm) are released from the endometrial epithelium into the uterine cavity, and that these contain specific micro (mi)RNA that could be transferred to either the trophectodermal cells of the blastocyst or to endometrial epithelial cells, to promote implantation. The aim of this study was to specifically identify and characterise exosomes/microvesicles (mv) released from endometrial epithelial cells and to determine whether exosomes/mv are present in uterine fluid. Immunostaining demonstrated that the tetraspanins, CD9 and CD63 used as cell surface markers of exosomes are present on the apical surfaces of endometrial epithelial cells in tissue sections taken across the menstrual cycle: CD63 showed cyclical regulation. Exosome/mv pellets were prepared from culture medium of endometrial epithelial cell (ECC1 cells) and from uterine fluid and its associated mucus by sequential ultracentifugation. Exosomes/mv were positively identified in all preparations by FACS and immunofluorescence staining following exosome binding to beads. Size particle analysis confirmed the predominance of particles of 50-150 nm in each of these fluids. MiRNA analysis of the ECC1 cells and their exosomes/mv demonstrated sorting of miRNA into exosomes/mv: 13 of the 227 miRNA were specific to exosomes/mv, while a further 5 were not present in these. The most abundant miRNA in exosomes/mv were hsa-miR-200c, hsa-miR-17 and hsa-miR-106a. Bioinformatic analysis showed that the exosome/mv-specific miRNAs have potential targets in biological pathways highly relevant for embryo implantation. Thus exosomes/mv containing specific miRNA are present in the microenvironment in which embryo implantation occurs and may contribute to the endometrial-embryo cross talk essential for this process.

Adenosine diphosphate ANOVA Analysis of variance ATP Adenosine triphosphate CK Creatine kinase CK-MB Creatine kinase-muscle/brain CMR Cardiac magnetic resonance imaging CsA Cyclosporine A ECG Electrocardiogram EGTA Ethylene glycol-bis(-aminoethyl ether)-N,N,N',N'-tetraacetic acid FCCP Carbonyl cyanide-4-(trifluoromethoxy) phenylhydrazone FCS Fetal calf serum HEPES 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid ICH International conference on harmonization IFM Interfibrillar mitochondria JC-1 Tetraethyl-benzimidazolyl-carbocyanine iodide KHB Krebs-Henseleit buffer LDH Lactate dehydrogenase LGE Late gadolinium enhancement LOCF Last observation carried forward MACCE Major adverse cardiac and cerebral events MOPS 3-(N-morpholino)propanesulfonic acid mPTP Mitochondrial permeability transition pore MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) tetrazolium PPCI Primary percutaneous coronary intervention RNA Ribonucleic acid ROS Reactive oxygen species SPECT Single-photon emission computed tomography SSM Subsarcolemmal mitochondria STEMI ST segment elevation myocardial infarction T2w-CMR T2-weighted cardiac magnetic resonance imaging TMRE Ethyl ester of tetramethylrhodamine TMRM Methyl ester of tetramethylrhodamine TTC 2,3,5-triphenyl tetrazolium chloride

Mitochondria-associated endoplasmic reticulum (ER) membranes (MAMs) are functional domains between both organelles involved in Ca(2+) exchange, through the voltage-dependent anion channel (VDAC)-1/glucose-regulated protein 75 (Grp75)/inositol 1,4,5-triphosphate receptor (IP3R)-1 complex, and regulating energy metabolism. Whereas mitochondrial dysfunction, ER stress, and altered Ca(2+) homeostasis are associated with altered insulin signaling, the implication of MAM dysfunctions in insulin resistance is unknown. Here we validated an approach based on in situ proximity ligation assay to detect and quantify VDAC1/IP3R1 and Grp75/IP3R1 interactions at the MAM interface. We demonstrated that MAM integrity is required for insulin signaling and that induction of MAM prevented palmitate-induced alterations of insulin signaling in HuH7 cells. Disruption of MAM integrity by genetic or pharmacological inhibition of the mitochondrial MAM protein, cyclophilin D (CypD), altered insulin signaling in mouse and human primary hepatocytes and treatment of CypD knockout mice with metformin improved both insulin sensitivity and MAM integrity. Furthermore, ER-mitochondria interactions are altered in liver of both ob/ob and diet-induced insulin-resistant mice and improved by rosiglitazone treatment in the latter. Finally, increasing organelle contacts by overexpressing CypD enhanced insulin action in primary hepatocytes of diabetic mice. Collectively, our data reveal a new role of MAM integrity in hepatic insulin action and resistance, providing a novel target for the modulation of insulin action.

BACKGROUND AND PURPOSE: This American Heart Association (AHA) scientific statement provides a comprehensive overview of current evidence on the burden cardiovascular disease (CVD) among Hispanics in the United States. Hispanics are the largest minority ethnic group in the United States, and their health is vital to the public health of the nation and to achieving the AHA's 2020 goals. This statement describes the CVD epidemiology and related personal beliefs and the social and health issues of US Hispanics, and it identifies potential prevention and treatment opportunities. The intended audience for this statement includes healthcare professionals, researchers, and policy makers. METHODS: Writing group members were nominated by the AHA's Manuscript Oversight Committee and represent a broad range of expertise in relation to Hispanic individuals and CVD. The writers used a general framework outlined by the committee chair to produce a comprehensive literature review that summarizes existing evidence, indicate gaps in current knowledge, and formulate recommendations. Only English-language studies were reviewed, with PubMed/MEDLINE as our primary resource, as well as the Cochrane Library Reviews, Centers for Disease Control and Prevention, and the US Census data as secondary resources. Inductive methods and descriptive studies that focused on CVD outcomes incidence, prevalence, treatment response, and risks were included. Because of the wide scope of these topics, members of the writing committee were responsible for drafting individual sections selected by the chair of the writing committee, and the group chair assembled the complete statement. The conclusions of this statement are the views of the authors and do not necessarily represent the official view of the AHA. All members of the writing group had the opportunity to comment on the initial drafts and approved the final version of this document. The manuscript underwent extensive AHA internal peer review before consideration and approval by the AHA Science Advisory and Coordinating Committee. RESULTS: This statement documents the status of knowledge regarding CVD among Hispanics and the sociocultural issues that impact all subgroups of Hispanics with regard to cardiovascular health. In this review, whenever possible, we identify the specific Hispanic subgroups examined to avoid generalizations. We identify specific areas for which current evidence was less robust, as well as inconsistencies and evidence gaps that inform the need for further rigorous and interdisciplinary approaches to increase our understanding of the US Hispanic population and its potential impact on the public health and cardiovascular health of the total US population. We provide recommendations specific to the 9 domains outlined by the chair to support the development of these culturally tailored and targeted approaches. CONCLUSIONS: Healthcare professionals and researchers need to consider the impact of culture and ethnicity on health behavior and ultimately health outcomes. There is a need to tailor and develop culturally relevant strategies to engage Hispanics in cardiovascular health promotion and cultivate a larger workforce of healthcare providers, researchers, and allies with the focused goal of improving cardiovascular health and reducing CVD among the US Hispanic population.

Niemann-Pick C disease (NP-C) is a neurovisceral lysosomal storage disorder. A variety of studies have highlighted defective sterol trafficking from lysosomes in NP-C cells. However, the heterogeneous nature of additional accumulating metabolites suggests that the cellular lesion may involve a more generalized block in retrograde lysosomal trafficking. Immunocytochemical studies in fibroblasts reveal that the NPC1 gene product resides in a novel set of lysosome-associated membrane protein-2 (LAMP2)(+)/mannose 6-phosphate receptor(-) vesicles that can be distinguished from cholesterol-enriched LAMP2(+) lysosomes. Drugs that block sterol transport out of lysosomes also redistribute NPC1 to cholesterol-laden lysosomes. Sterol relocation from lysosomes in cultured human fibroblasts can be blocked at 21 degrees C, consistent with vesicle-mediated transfer. These findings suggest that NPC1(+) vesicles may transiently interact with lysosomes to facilitate sterol relocation. Independent of defective sterol trafficking, NP-C fibroblasts are also deficient in vesicle-mediated clearance of endocytosed [14C]sucrose. Compartmental modeling of the observed [14C]sucrose clearance data targets the trafficking defect caused by mutations in NPC1 to an endocytic compartment proximal to lysosomes. Low density lipoprotein uptake by normal cells retards retrograde transport of [14C]sucrose through this same kinetic compartment, further suggesting that it may contain the sterol-sensing NPC1 protein. We conclude that a distinctive organelle containing NPC1 mediates retrograde lysosomal transport of endocytosed cargo that is not restricted to sterol.

Glycine is the proteinogenic amino-acid of lowest molecular weight, harboring a hydrogen atom as a side-chain. In addition to being a building-block for proteins, glycine is also required for multiple metabolic pathways, such as glutathione synthesis and regulation of one-carbon metabolism. Although generally viewed as a non-essential amino-acid, because it can be endogenously synthesized to a certain extent, glycine has also been suggested as a conditionally essential amino acid. In metabolic disorders associated with obesity, type 2 diabetes (T2DM), and non-alcoholic fatty liver disease (NAFLDs), lower circulating glycine levels have been consistently observed, and clinical studies suggest the existence of beneficial effects induced by glycine supplementation. The present review aims at synthesizing the recent advances in glycine metabolism, pinpointing its main metabolic pathways, identifying the causes leading to glycine deficiency-especially in obesity and associated metabolic disorders-and evaluating the potential benefits of increasing glycine availability to curb the progression of obesity and obesity-related metabolic disturbances. This study focuses on the importance of diet, gut microbiota, and liver metabolism in determining glycine availability in obesity and associated metabolic disorders.