BACKGROUND. High circulating levels of ceramides (Cer) and sphingomyelins (SM) have been associated with cardiometabolic diseases. The consumption of whole-fat dairy products, which naturally contain such polar lipids (PL), is associated with health benefits, but the impact on sphingolipidome remains unknown. We investigated how milk PL supplementation impacts circulating and intestinal SM and Cer composition in association with improvement of cardiovascular markers. METHODS. In a 4 week-randomized double-blind controlled study, 58 postmenopausal women consumed daily a cream cheese containing 0, 3 or 5 g of milk PL. Postprandial metabolic explorations were performed before and after the supplementation. SM and Cer species were analyzed in serum, intestine-derived chylomicrons and feces. The ileal content of 4 ileostomy patients was also explored after milk PL intake in a crossover double-blind study. RESULTS. Milk PL consumption decreased serum atherogenic C24:1 Cer (Pgroup = 0.033), C16:1 (Pgroup = 0.007) and C18:1 (Pgroup = 0.003) SM species. Changes in serum C16+18 SM species were positively correlated with the reduction of total cholesterol (r = 0.706, P < 0.001), LDL-C (r = 0.666, P < 0.001) and ApoB (r = 0.705, P < 0.001). Milk PL decreased the concentration in chylomicrons of total SM (Pgroup < 0.0001) and of C24:1 Cer (Pgroup = 0.001). Saturated SM and Cer species, which are also the major species found in milk PL-enriched cheeses, increased in ileal efflux and feces. There was a marked increase in total fecal Cer after milk PL supplementation (Pgroup = 0.0002). Milk PL also modulated the abundance of some specific SM and Cer species in ileal efflux and feces, suggesting differential absorption and metabolization processes in the gut. CONCLUSION. These data demonstrate that milk PL supplementation decreases atherogenic SM and Cer species associated with an improvement of cardiovascular risk markers. Our findings bring new insights on sphingolipid metabolism in the gastrointestinal tract, especially Cer as such signaling molecules potentially participating in the beneficial effect of milk PL. ClinicalTrials.gov, NCT02099032, NCT02146339. FUNDINGS. Agence Nationale de la Recherche, ANR-11-ALID-007-01; Regional Hospital Clinical Research Program (PHRCI-2014: VALOBAB, n°14-007); French Dairy Interbranch Organization (CNIEL); Groupe Lipides et Nutrition (GLN 2018-11-07), Hospices Civils de Lyon as sponsor.
Mélanie Le Barz, Cécile Vors, Emmanuel Combe, Laurie Joumard-Cubizolles, Manon Lecomte, Florent Joffre, Michèle Trauchessec, Sandra Pesenti, Emmanuelle Loizon, Anne-Esther Breyton, Emmanuelle Meugnier, Karène Bertrand, Jocelyne Drai, Chloé Robert, Annie Durand, Charlotte Cuerq, Patrice Gaborit, Nadine Leconte, Annick Bernalier-Donadille, Eddy Cotte, Martine Laville, Stéphanie Lambert-Porcheron, Lemlih Ouchchane, Hubert Vidal, Corinne Malpuech-Brugère, David Cheillan, Marie-Caroline Michalski
Antipsychotics often cause tardive dyskinesia, an adverse symptom of involuntary hyperkinetic movements. Analysis of the U.S. Food and Drug Administration Adverse Event Reporting System and JMDC insurance claims revealed that acetaminophen prevents the dyskinesia induced by dopamine D2 receptor antagonists. In vivo experiments further showed that a 21-day treatment with haloperidol increased the number of vacuous chewing movements (VCMs) in rats, an effect that was inhibited by oral acetaminophen treatment or intracerebroventricular injection of N-(4-hydroxyphenyl)-arachidonylamide (AM404), an acetaminophen metabolite that acts as an activator of the transient receptor potential vanilloid 1 (TRPV1). In mice, haloperidol-induced VCMs were also mitigated by treatment with AM404 applied to the dorsal striatum, but not in TRPV1-deficient mice. Acetaminophen prevented the haloperidol-induced decrease in the number of c-Fos+/preproenkephalin+ striatal neurons in wild-type mice but not in TRPV1-deficient mice. Finally, chemogenetic stimulation of indirect-pathway medium spiny neurons in the dorsal striatum decreased haloperidol-induced VCMs. These results suggest that acetaminophen activates the indirect pathway neurons by activating TRPV1 channels via AM404.
Koki Nagaoka, Takuya Nagashima, Nozomi Asaoka, Hiroki Yamamoto, Chihiro Toda, Gen Kayanuma, Soni Siswanto, Yasuhiro Funahashi, Keisuke Kuroda, Kozo Kaibuchi, Yasuo Mori, Kazuki Nagayasu, Hisashi Shirakawa, Shuji Kaneko
The recently proposed glymphatic pathway for solute transport and waste clearance from the brain has been the focus of intense debate. By exploiting an isotopically enriched MRI tracer, H217O, we directly imaged glymphatic water transport in the rat brain in vivo for the first time. Our results reveal glymphatic transport that is dramatically faster and more extensive than previously thought and unlikely to be explained by diffusion alone. Moreover, we confirm the critical role of aquaporin-4 channels in glymphatic transport.
Mohammed S. Alshuhri, Lindsay Gallagher, Lorraine M. Work, William M. Holmes
Skeletal muscle can regenerate from muscle stem cells and their myogenic precursor cell progeny, myoblasts. However, precise gene editing in human muscle stem cells for autologous cell replacement therapies of untreatable genetic muscle diseases has not yet been reported. Loss-of-function mutations in SGCA, encoding α-sarcoglycan, cause limb-girdle muscular dystrophy 2D/R3, an early onset, severe and rapidly progressive form of muscular dystrophy affecting equally girls and boys. Patients suffer from muscle degeneration and atrophy affecting the limbs, respiratory muscles, and the heart. We isolated human muscle stem cells from two donors with the common SGCA c.157G>A mutation affecting the last coding nucleotide of exon 2. We found that c.157G>A is an exonic splicing mutation that induces skipping of two co-regulated exons. Using adenine base editing, we corrected the mutation in the cells from both donors with >90% efficiency, thereby rescuing the splicing defect and α-sarcoglycan expression. Base edited patient cells regenerated muscle and contributed to the Pax7 positive satellite cell compartment in vivo in mouse xenografts. We hereby provide the first evidence that autologous gene repaired human muscle stem cells can be harnessed for cell replacement therapies of muscular dystrophies.
Helena Escobar, Anne Krause, Sandra Keiper, Janine Kieshauer, Stefanie Müthel, Manuel García de Paredes, Eric Metzler, Ralf Kühn, Florian Heyd, Simone Spuler
Bariatric surgery is the most effective method for weight loss in morbid obesity. There is significant individual variability in the weight loss outcomes, yet factors leading to postoperative weight loss or weight regain remain elusive. Alterations in the µ-opioid receptor (MOR) and dopamine D2 receptor (D2R) systems are associated with obesity and appetite control, and the magnitude of initial brain receptor system perturbation may predict long-term surgical weight loss outcomes. We tested this hypothesis by studying 19 morbidly obese women (mean BMI 40) scheduled to undergo bariatric surgery. We measured their preoperative MOR and D2R availabilities using positron emission tomography (PET) with [11C]carfentanil and [11C]raclopride, respectively, and then assessed their weight development association with regional MOR and D2R availabilities at 24-month follow-up. MOR availability in the amygdala consistently predicted weight development throughout the follow-up period, but no associations were found for D2R. This is the first study to demonstrate that neuroreceptor markers prior to bariatric surgery are associated with the postoperative weight loss. Postoperative weight regain may derive from dysfunction in the opioid system, and weight loss outcomes after bariatric surgery may be partially predicted based on preoperative brain receptor availability opening up new potential for treatment possibilities.
Henry K. Karlsson, Lauri Tuominen, Semi Helin, Paulina Salminen, Pirjo Nuutila, Lauri Nummenmaa
BACKGROUND. Idiopathic intracranial hypertension (IIH) is a condition predominantly affecting obese women of reproductive age. Recent evidence suggests that IIH is a disease of metabolic dysregulation, androgen excess and an increased risk of cardiovascular morbidity. Here we evaluate systemic and adipose specific metabolic determinants of the IIH phenotype. METHODS. In fasted, matched IIH (N=97) and control (N=43) patients, we assessed: glucose and insulin homeostasis and leptin levels. Body composition was assessed along with an interrogation of adipose tissue function via nuclear magnetic resonance metabolomics and RNA sequencing in paired omental and subcutaneous biopsies in a case control study. RESULTS. We demonstrate an insulin and leptin resistant phenotype in IIH in excess to that driven by obesity. Adiposity in IIH is preferentially centripetal and is associated with increased disease activity and insulin resistance. IIH adipocytes appear transcriptionally and metabolically primed towards depot-specific lipogenesis. CONCLUSIONS. These data show that IIH is a metabolic disorder in which adipose tissue dysfunction is a feature of the disease. Managing IIH as a metabolic disease could reduce disease morbidity and improving cardiovascular outcomes. FUNDING. This study was supported by the National Institute of Health Research UK (NIHR-CS-011-028), the Medical Research Council UK (MR/K015184/1) and the Midlands Neuroscience Teaching and Research Fund.
Connar S.J. Westgate, Hannah F. Botfield, Zerin Alimajstorovic, Andreas Yiangou, Mark Walsh, Gabrielle Smith, Rishi Singhal, James L. Mitchell, Olivia Grech, Keira A. Markey, Daniel Hebenstreit, Daniel A. Tennant, Jeremy W. Tomlinson, Susan P. Mollan, Christian Ludwig, Ildem Akerman, Gareth G. Lavery, Alexandra J. Sinclair
Retinoic acid (RA) signaling is essential for enteric nervous system (ENS) development since vitamin A deficiency or mutations in RA signaling profoundly reduce bowel colonization by ENS precursors. These RA effects could occur because of RA activity within the ENS lineage or via RA activity in other cell types. To define cell-autonomous roles for retinoid signaling within the ENS lineage at distinct developmental time points, we activated a potent floxed dominant-negative RA receptor α (RarαDN) in the ENS using diverse CRE recombinase-expressing mouse lines. This strategy enabled us to block RA signaling at pre-migratory, migratory, and post-migratory stages for ENS precursors. We found that cell-autonomous loss of retinoic acid receptor (RAR) signaling dramatically affects ENS development. CRE activation of RarαDN expression at pre-migratory or migratory stages caused severe intestinal aganglionosis, but at later stages, RarαDN induced a broad range of phenotypes including hypoganglionosis, submucosal plexus loss, and abnormal neural differentiation. RNA-sequencing highlighted distinct RA-regulated gene sets at different developmental stages. These studies show complicated context-dependent RA-mediated regulation of ENS development.
Tao Gao, Elizabeth C. Wright-Jin, Rajarshi Sengupta, Jessica B. Anderson, Robert O. Heuckeroth
Transitions between cell fates commonly occur in development and disease. However, reversing an unwanted cell transition in order to treat disease remains an unexplored area. Here, we report a successful process of guiding ill-fated transitions toward normalization in vascular calcification. Vascular calcification is a severe complication that increases all-cause mortality of cardiovascular disease but lacks medical therapy. The vascular endothelium is a contributor of osteoprogenitor cells to vascular calcification through endothelial-mesenchymal transitions, in which endothelial cells (ECs) gain plasticity and ability to differentiate into osteoblast-like cells. We created a high throughput screening and identified SB216763, an inhibitor of glycogen synthase kinase 3 (GSK3), as an inducer of osteoblastic-endothelial transition. We demonstrated that SB216763 limits osteogenic differentiation in ECs at an early stage of vascular calcification. Lineage tracing showed that SB216763 redirected osteoblast-like cells to the endothelial lineage and reduced late-stage calcification. We also find that deletion of GSK3beta in osteoblasts recapitulated osteoblastic-endothelial transition and reduced vascular calcification. Overall, inhibition of GSK3beta promoted the transition of cells with osteoblastic characteristic to endothelial differentiation thereby ameliorating vascular calcification.
Jiayi Yao, Xiuju Wu, Xiaojing Qiao, Daoqin Zhang, Li Zhang, Jocelyn A. Ma, Xinjiang Cai, Kristina I. Boström, Yucheng Yao
Left ventricular hypertrophy (LVH) is a primary feature of cardiovascular complications in chronic kidney disease (CKD) patients. MiRNA-30 is an important posttranscriptional regulator of LVH, but it is unknown whether miRNA-30 participates in the process of CKD-induced LVH. In the present study, we found that CKD not only results in LVH but also suppresses miRNA-30 expression in the myocardium. Rescue of cardiomyocyte-specific miRNA-30 attenuates LVH in CKD rats without altering CKD progression. Importantly, in vivo and in vitro knockdown of miRNA-30 in cardiomyocytes leads to cardiomyocyte hypertrophy by upregulating the calcineurin signalling directly. Furthermore, CKD-related detrimental factors, such as fibroblast growth factor-23 (FGF-23), uraemic toxin, angiotensin-II (Ang-II) and transforming growth factor-β (TGF-β), suppress cardiac miRNA-30 expression, while miRNA-30 supplementation blunts cardiomyocyte hypertrophy induced by such factors. These results uncover a novel mechanism of CKD-induced LVH and provide a potential therapeutic target for CKD patients with LVH.
Jingfu Bao, Yinghui Lu, Qin-ying She, Weijuan Dou, Rong Tang, Xiaodong Xu, Mingchao Zhang, Ling Zhu, Qing Zhou, Hui Li, Guohua Zhou, Zhongzhou Yang, Shaolin Shi, Zhihong Liu, Chunxia Zheng
Endothelial cells are important in the maintenance of healthy blood vessels and in the development of vascular diseases. However, the origin and dynamics of endothelial precursors and remodeling at the single-cell level have been difficult to study in vivo due to technical limitations. We aimed to develop a direct visual approach to track the fate and function of single endothelial cells over several days-weeks in the same vascular bed in vivo using multiphoton microscopy (MPM) of transgenic Cdh5-Confetti mice and the kidney glomerulus as a model. Individual cells of the vascular endothelial lineage were identified and tracked due to their unique color combination, based on the random expression of cyan/green/yellow/red fluorescent proteins. Experimental hypertension, hyperglycemia, and laser-induced endothelial cell ablation rapidly increased the number of new glomerular endothelial cells that appeared in clusters of the same color, suggesting clonal cell remodeling by local precursors at the vascular pole. Furthermore, intravital MPM allowed the detection of distinct structural and functional alterations of proliferating endothelial cells. No circulating Cdh5-Confetti+ cells were found in the renal cortex. The heart, lung, and kidneys showed more significant clonal endothelial cell expansion compared to the brain, pancreas, liver and spleen. Serial MPM of Cdh5-Confetti mice in vivo is a powerful new technical advance to study endothelial remodeling and repair in the kidney and other organs under physiological and disease conditions.
Dorinne Desposito, Ina Maria Schiessl, Georgina Gyarmati, Anne Riquier-Brison, Audrey Izuhara, Hiroyuki Kadoya, Balint Der, Urvi Nikhil Shroff, Young-Kwon Hong, Janos Peti-Peterdi
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