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1.
J Perianesth Nurs ; 36(5): 468-472, 2021 10.
Article in English | MEDLINE | ID: mdl-33965327

ABSTRACT

PURPOSE: Enhanced recovery after surgery (ERAS) programs comprise bundles of evidence-based recommendations designed to reduce physiological stress and support early return of function after surgery. In this study, we sought to investigate the barriers and facilitators of successful implementation of ERAS in a major safety-net hospital. DESIGN: Our ERAS program has been designed as a quality improvement pilot project in prospective fashion with a real-time feedback loop. The program is designed to address established culture of safety-net hospitals. METHODS: An extensive multidisciplinary team investigated the barriers to success for three different levels of program stakeholders: providers, patients, and the facility. After a systematic review of these barriers, solutions were offered and implemented in a multidisciplinary care model with special attention to outcomes and continuous feedback. The findings are summarized in a grid format for better understanding and implementation ease. FINDINGS: Patients (N = 198) were enrolled in an ERAS program in a nonrandomized fashion during the pilot period of October 2017 to August 2018. ERAS cohort of patients' outcomes were then compared with those of 20,328 non-ERAS patients. The ERAS group had less complication with shorter length of stay compared with their non-ERAS counterparts. Furthermore, it has cost less to take care of these patients. Interestingly, this decrease was not achieved by a reciprocal increase in subsequent readmission or reoperation rates. CONCLUSIONS: Unique barriers exist when implementing an ERAS protocol in a safety-net hospital. These barriers can be overcome to improve the quality of care at a decreased cost. We have provided a grid to facilitate the implementation process.


Subject(s)
Enhanced Recovery After Surgery , Safety-net Providers , Humans , Pilot Projects , Quality Improvement
2.
Hum Mol Genet ; 26(24): 4836-4848, 2017 12 15.
Article in English | MEDLINE | ID: mdl-29036432

ABSTRACT

Primary microcephaly is a congenital brain malformation characterized by a head circumference less than three standard deviations below the mean for age and sex and results in moderate to severe mental deficiencies and decreased lifespan. We recently studied two children with primary microcephaly in an otherwise unaffected family. Exome sequencing identified an autosomal recessive mutation leading to an amino acid substitution in a WD40 domain of the highly conserved Coatomer Protein Complex, Subunit Beta 2 (COPB2). To study the role of Copb2 in neural development, we utilized genome-editing technology to generate an allelic series in the mouse. Two independent null alleles revealed that Copb2 is essential for early stages of embryogenesis. Mice homozygous for the patient variant (Copb2R254C/R254C) appear to have a grossly normal phenotype, likely due to differences in corticogenesis between the two species. Strikingly, mice heterozygous for the patient mutation and a null allele (Copb2R254C/Zfn) show a severe perinatal phenotype including low neonatal weight, significantly increased apoptosis in the brain, and death within the first week of life. Immunostaining of the Copb2R254C/Zfnbrain revealed a reduction in layer V (CTIP2+) neurons, while the overall cell density of the cortex is unchanged. Moreover, neurospheres derived from animals with Copb2 variants grew less than control. These results identify a general requirement for COPB2 in embryogenesis and a specific role in corticogenesis. We further demonstrate the utility of CRISPR-Cas9 generated mouse models in the study of potential pathogenicity of variants of potential clinical interest.


Subject(s)
Coatomer Protein/genetics , Microcephaly/genetics , Animals , Child , Disease Models, Animal , Embryonic Development/genetics , Female , Gene Frequency , Heterozygote , Homozygote , Humans , Intellectual Disability/genetics , Male , Mice , Mutation , Pedigree , WD40 Repeats , Exome Sequencing
3.
Circ Cardiovasc Genet ; 9(6): 474-486, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27780848

ABSTRACT

BACKGROUND: Cardiac metabolism is critical for the functioning of the heart, and disturbance in this homeostasis is likely to influence cardiac disorders or cardiomyopathy. Our laboratory has previously shown that SNRK (sucrose nonfermenting related kinase) enzyme, which belongs to the AMPK (adenosine monophosphate-activated kinase) family, was essential for cardiac metabolism in mammals. Snrk global homozygous knockout (KO) mice die at postnatal day 0, and conditional deletion of Snrk in cardiomyocytes (Snrk cmcKO) leads to cardiac failure and death by 8 to 10 months. METHODS AND RESULTS: We performed additional cardiac functional studies using echocardiography and identified further cardiac functional deficits in Snrk cmcKO mice. Nuclear magnetic resonance-based metabolomics analysis identified key metabolic pathway deficits in SNRK knockdown cardiomyocytes in vitro. Specifically, metabolites involved in lipid metabolism and oxidative phosphorylation are altered, and perturbations in these pathways can result in cardiac function deficits and heart failure. A phosphopeptide-based proteomic screen identified ROCK (Rho-associated kinase) as a putative substrate for SNRK, and mass spec-based fragment analysis confirmed key amino acid residues on ROCK that are phosphorylated by SNRK. Western blot analysis on heart lysates from Snrk cmcKO adult mice and SNRK knockdown cardiomyocytes showed increased ROCK activity. In addition, in vivo inhibition of ROCK partially rescued the in vivo Snrk cmcKO cardiac function deficits. CONCLUSIONS: Collectively, our data suggest that SNRK in cardiomyocytes is responsible for maintaining cardiac metabolic homeostasis, which is mediated in part by ROCK, and alteration of this homeostasis influences cardiac function in the adult heart.


Subject(s)
Embryonic Stem Cells/enzymology , Energy Metabolism , Heart Failure/enzymology , Myocytes, Cardiac/enzymology , Protein Serine-Threonine Kinases/metabolism , rho-Associated Kinases/metabolism , Animals , Cells, Cultured , Echocardiography , Embryonic Stem Cells/drug effects , Embryonic Stem Cells/pathology , Energy Metabolism/drug effects , Fibrosis , Genetic Predisposition to Disease , Heart Failure/genetics , Heart Failure/pathology , Heart Failure/physiopathology , Homozygote , Human Umbilical Vein Endothelial Cells/enzymology , Lipid Metabolism , Magnetic Resonance Spectroscopy , Metabolomics/methods , Mice, Knockout , Myocytes, Cardiac/drug effects , Myocytes, Cardiac/pathology , Oxidative Phosphorylation , Phenotype , Protein Kinase Inhibitors/pharmacology , Protein Serine-Threonine Kinases/deficiency , Protein Serine-Threonine Kinases/genetics , RNA Interference , Signal Transduction , Transfection , rho-Associated Kinases/antagonists & inhibitors
4.
PLoS One ; 10(12): e0144185, 2015.
Article in English | MEDLINE | ID: mdl-26692198

ABSTRACT

Elevated plasma triglycerides are associated with increased susceptibility to heart disease and stroke, but the mechanisms behind this relationship are unclear. A clearer understanding of gene products which influence plasma triglycerides might help identify new therapeutic targets for these diseases. The Endothelial Cell Surface expressed Chemotaxis and apoptosis Regulator (ECSCR) was initially studied as an endothelial cell marker, but has recently been identified in white adipocytes, the primary storage cell type for triglycerides. Here we confirm ECSCR expression in white adipocytes and show that Ecscr knockout mice show elevated fasting plasma triglycerides. At a cellular level, cultured 3T3-L1 adipocytes silenced for Ecscr show a blunted Akt phosphorylation response. Additionally we show that the phosphatase and tensin homology containing (PTEN) lipid phosphatase association with ECSCR is increased by insulin stimulation. These data suggest a scenario by which ECSCR contributes to control of white adipocyte lipolysis. In this scenario, white adipocytes lacking Ecscr display elevated PTEN activity, thereby reducing AKT activation and impairing insulin-mediated suppression of lipolysis. Collectively, these results suggest that ECSCR plays a critical function in regulating lipolysis in white adipose tissue.


Subject(s)
Adipocytes, White/metabolism , Apoptosis Regulatory Proteins/metabolism , Lipolysis/physiology , PTEN Phosphohydrolase/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction/physiology , 3T3-L1 Cells , Adipocytes, White/cytology , Animals , Apoptosis Regulatory Proteins/genetics , Membrane Proteins , Mice , Mice, Knockout , PTEN Phosphohydrolase/genetics , Proto-Oncogene Proteins c-akt/genetics , Triglycerides/genetics , Triglycerides/metabolism
6.
Nat Commun ; 5: 4993, 2014 Sep 26.
Article in English | MEDLINE | ID: mdl-25256100

ABSTRACT

A prerequisite to myelination of peripheral axons by Schwann cells (SCs) is SC differentiation, and recent evidence indicates that reprogramming from a glycolytic to oxidative metabolism occurs during cellular differentiation. Whether this reprogramming is essential for SC differentiation, and the genes that regulate this critical metabolic transition are unknown. Here we show that the tumour suppressor Lkb1 is essential for this metabolic transition and myelination of peripheral axons. Hypomyelination in the Lkb1-mutant nerves and muscle atrophy lead to hindlimb dysfunction and peripheral neuropathy. Lkb1-null SCs failed to optimally activate mitochondrial oxidative metabolism during differentiation. This deficit was caused by Lkb1-regulated diminished production of the mitochondrial Krebs cycle substrate citrate, a precursor to cellular lipids. Consequently, myelin lipids were reduced in Lkb1-mutant mice. Restoring citrate partially rescued Lkb1-mutant SC defects. Thus, Lkb1-mediated metabolic shift during SC differentiation increases mitochondrial metabolism and lipogenesis, necessary for normal myelination.


Subject(s)
Mitochondria/metabolism , Myelin Sheath/metabolism , Protein Serine-Threonine Kinases/metabolism , Tumor Suppressor Proteins/metabolism , AMP-Activated Protein Kinases , Animals , Cell Differentiation , Female , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Mitochondria/enzymology , Protein Serine-Threonine Kinases/genetics , Schwann Cells/cytology , Schwann Cells/enzymology , Schwann Cells/metabolism , Tumor Suppressor Proteins/genetics
7.
Proc Natl Acad Sci U S A ; 111(4): E435-44, 2014 Jan 28.
Article in English | MEDLINE | ID: mdl-24474794

ABSTRACT

The multifunctional AMPK-activated protein kinase (AMPK) is an evolutionarily conserved energy sensor that plays an important role in cell proliferation, growth, and survival. It remains unclear whether AMPK functions as a tumor suppressor or a contextual oncogene. This is because although on one hand active AMPK inhibits mammalian target of rapamycin (mTOR) and lipogenesis--two crucial arms of cancer growth--AMPK also ensures viability by metabolic reprogramming in cancer cells. AMPK activation by two indirect AMPK agonists AICAR and metformin (now in over 50 clinical trials on cancer) has been correlated with reduced cancer cell proliferation and viability. Surprisingly, we found that compared with normal tissue, AMPK is constitutively activated in both human and mouse gliomas. Therefore, we questioned whether the antiproliferative actions of AICAR and metformin are AMPK independent. Both AMPK agonists inhibited proliferation, but through unique AMPK-independent mechanisms and both reduced tumor growth in vivo independent of AMPK. Importantly, A769662, a direct AMPK activator, had no effect on proliferation, uncoupling high AMPK activity from inhibition of proliferation. Metformin directly inhibited mTOR by enhancing PRAS40's association with RAPTOR, whereas AICAR blocked the cell cycle through proteasomal degradation of the G2M phosphatase cdc25c. Together, our results suggest that although AICAR and metformin are potent AMPK-independent antiproliferative agents, physiological AMPK activation in glioma may be a response mechanism to metabolic stress and anticancer agents.


Subject(s)
Cell Cycle/physiology , Protein Kinases/drug effects , TOR Serine-Threonine Kinases/physiology , AMP-Activated Protein Kinase Kinases , Animals , Brain Neoplasms/enzymology , Brain Neoplasms/metabolism , Brain Neoplasms/pathology , Cell Proliferation/drug effects , Cells, Cultured , Glioblastoma/enzymology , Glioblastoma/metabolism , Glioblastoma/pathology , Humans , Lipogenesis/drug effects , Metformin/pharmacology , Mice , Mice, Knockout , Protein Kinases/genetics
8.
Br J Nutr ; 109(4): 667-77, 2013 Feb 28.
Article in English | MEDLINE | ID: mdl-22794784

ABSTRACT

Dietary methyl donors and their genetic determinants are associated with Crohn's disease risk. We investigated whether a methyl-deficient diet (MDD) may affect development and functions of the small intestine in rat pups from dams subjected to the MDD during gestation and lactation. At 1 month before pregnancy, adult females were fed with either a standard food or a diet without vitamin B12, folate and choline. A global wall hypotrophy was observed in the distal small bowel (MDD animals 0·30 mm v. controls 0·58 mm; P< 0·001) with increased crypt apoptosis (3·37 v. 0·4%; P< 0·001), loss of enterocyte differentiation in the villus and a reduction in intestinal alkaline phosphatase production. Cleaved caspase-3 immunostaining (MDD animals 3·37% v. controls 0·4%, P< 0·001) and the Apostain labelling index showed increased crypt apoptosis (3·5 v. 1·4%; P= 0·018). Decreased proliferation was observed in crypts of the proximal small bowel with a reduced number of minichromosome maintenance 6 (MDD animals 52·83% v. controls 83·17%; P= 0·048) and proliferating cell nuclear antigen-positive cells (46·25 v. 59 %; P= 0·05). This lack of enterocyte differentiation in the distal small bowel was associated with an impaired expression of ß-catenin and a decreased ß-catenin-E-cadherin interaction. The MDD affected the intestinal barrier in the proximal small bowel by decreasing Paneth cell number after immunostaining for lysosyme (MDD animals 8·66% v. controls 21·66%) and by reducing goblet cell number and mucus production after immunostaining for mucin-2 (crypts 8·66 v. 15·33%; villus 7 v. 17%). The MDD has dual effects on the small intestine by producing dramatic effects on enterocyte differentiation and barrier function in rats.


Subject(s)
Choline Deficiency/metabolism , Enterocytes/cytology , Folic Acid Deficiency/metabolism , Intestine, Small/pathology , Vitamin B 12 Deficiency/metabolism , Alkaline Phosphatase/metabolism , Animal Feed , Animals , Apoptosis , Cadherins/metabolism , Caspase 3/metabolism , Cell Differentiation , Choline/metabolism , Female , Folic Acid/metabolism , Gene Expression Regulation , Muramidase/metabolism , Paneth Cells/metabolism , Rats , Rats, Wistar , Time Factors , Vitamin B 12/metabolism , beta Catenin/metabolism
9.
Singapore Med J ; 53(9): 615-9, 2012 Sep.
Article in English | MEDLINE | ID: mdl-23023905

ABSTRACT

INTRODUCTION: Consumption of omega-3 fatty acids can alter the inflammatory response in diabetic patients. This study aimed to determine the effects of omega-3 fatty acid supplementation on the serum levels of C-reactive protein (CRP), interleukin (IL)-2 and tumour necrosis factor-alpha (TNF-α) in type 2 diabetes mellitus patients. METHODS: A randomised, double-blind, placebo-controlled clinical trial was conducted on 84 subjects aged 45-85 years with at least a two-year history of type 2 diabetes mellitus. Participants were randomly assigned to the treatment or control group. Each subject in the treatment group received three omega-3 capsules per day (eicosapentaenoic acid 1,548 mg; docosahexaenoic acid 828 mg; other omega-3 fatty acids 338 mg), while each subject in the control group received three placebo capsules (sunflower oil 2,100 mg) for a period of eight weeks. At the beginning of the study and post intervention, fasting blood samples were taken and serum concentrations of IL-2, TNF-α and CRP were assessed and compared. RESULTS: Serum IL-2 and TNF-α levels were significantly reduced in the treatment group compared to the controls (p < 0.01). There was no significant change in serum CRP levels. CONCLUSION: Short-term omega-3 fatty acid supplementation (3 g/day for eight weeks) can decrease the serum levels of TNF-α and IL-2 in diabetic patients, with no change in CRP levels. Consumption of omega-3 fatty acid supplements is highly recommended to alleviate inflammation caused by type 2 diabetes mellitus.


Subject(s)
C-Reactive Protein/metabolism , Diabetes Mellitus, Type 2/drug therapy , Dietary Supplements , Fatty Acids, Omega-3/therapeutic use , Inflammation/prevention & control , Interleukin-2/blood , Tumor Necrosis Factor-alpha/blood , Aged , Aged, 80 and over , Biomarkers/blood , C-Reactive Protein/drug effects , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/immunology , Double-Blind Method , Fatty Acids, Omega-3/pharmacology , Female , Humans , Inflammation/blood , Male , Middle Aged , Tumor Necrosis Factor-alpha/drug effects
10.
J Hepatol ; 57(2): 344-51, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22521344

ABSTRACT

BACKGROUND & AIMS: Folate and cobalamin are methyl donors needed for the synthesis of methionine, which is the precursor of S-adenosylmethionine, the substrate of methylation in epigenetic, and epigenomic pathways. Methyl donor deficiency produces liver steatosis and predisposes to metabolic syndrome. Whether impaired fatty acid oxidation contributes to this steatosis remains unknown. METHODS: We evaluated the consequences of methyl donor deficient diet in liver of pups from dams subjected to deficiency during gestation and lactation. RESULTS: The deprived rats had microvesicular steatosis, with increased triglycerides, decreased methionine synthase activity, S-adenosylmethionine, and S-adenosylmethionine/S-adenosylhomocysteine ratio. We observed no change in apoptosis markers, oxidant and reticulum stresses, and carnityl-palmitoyl transferase 1 activity, and a decreased expression of SREBP-1c. Impaired beta-oxidation of fatty acids and carnitine deficit were the predominant changes, with decreased free and total carnitines, increased C14:1/C16 acylcarnitine ratio, decrease of oxidation rate of palmitoyl-CoA and palmitoyl-L-carnitine and decrease of expression of novel organic cation transporter 1, acylCoA-dehydrogenase and trifunctional enzyme subunit alpha and decreased activity of complexes I and II. These changes were related to lower protein expression of ER-α, ERR-α and HNF-4α, and hypomethylation of PGC-1α co-activator that reduced its binding with PPAR-α, ERR-α, and HNF-4α. CONCLUSIONS: The liver steatosis resulted predominantly from hypomethylation of PGC1-α, decreased binding with its partners and subsequent impaired mitochondrial fatty acid oxidation. This link between methyl donor deficiency and epigenomic deregulations of energy metabolism opens new insights into the pathogenesis of fatty liver disease, in particular, in relation to the fetal programming hypothesis.


Subject(s)
Estrogen Receptor alpha/physiology , Fatty Acids/metabolism , Hepatocyte Nuclear Factor 4/physiology , Liver/metabolism , RNA-Binding Proteins/metabolism , Receptors, Estrogen/physiology , Transcription Factors/metabolism , Animals , Electron Transport , Endoplasmic Reticulum Stress , Energy Metabolism , Estrogen Receptor alpha/analysis , Fatty Liver/etiology , Folic Acid/blood , Hepatocyte Nuclear Factor 4/analysis , Methylation , Oxidation-Reduction , Oxidative Stress , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha , Rats , Rats, Wistar , Receptors, Estrogen/analysis , Vitamin B 12/blood , ERRalpha Estrogen-Related Receptor
11.
J Pathol ; 225(3): 324-35, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21633959

ABSTRACT

Cardiomyopathies occur by mechanisms that involve inherited and acquired metabolic disorders. Both folate and vitamin B12 deficiencies are associated with left ventricular dysfunction, but mechanisms that underlie these associations are not known. However, folate and vitamin B12 are methyl donors needed for the synthesis of S-adenosylmethionine, the substrate required for the activation by methylation of regulators of energy metabolism. We investigated the consequences of a diet lacking methyl donors in the myocardium of weaning rats from dams subjected to deficiency during gestation and lactation. Positron emission tomography (PET), microscope and metabolic examinations evidenced a myocardium hypertrophy, with cardiomyocyte enlargement, disturbed mitochondrial alignment, lipid droplets, decreased respiratory activity of complexes I and II and decreased S-adenosylmethionine:S-adenosylhomocysteine ratio. The increased concentrations of triglycerides and acylcarnitines were consistent with a deficit in fatty acid oxidation. These changes were explained by imbalanced acetylation/methylation of PGC-1α, through decreased expression of SIRT1 and PRMT1 and decreased S-adenosylmethionine:S-adenosylhomocysteine ratio, and by decreased expression of PPARα and ERRα. The main changes of the myocardium proteomic study were observed for proteins regulated by PGC-1α, PPARs and ERRα. These proteins, namely trifunctional enzyme subunit α-complex, short chain acylCoA dehydrogenase, acylCoA thioesterase 2, fatty acid binding protein-3, NADH dehydrogenase (ubiquinone) flavoprotein 2, NADH dehydrogenase (ubiquinone) 1α-subunit 10 and Hspd1 protein, are involved in fatty acid oxidation and mitochondrial respiration. In conclusion, the methyl donor deficiency produces detrimental effects on fatty acid oxidation and energy metabolism of myocardium through imbalanced methylation/acetylation of PGC-1α and decreased expression of PPARα and ERRα. These data are of pathogenetic relevance to perinatal cardiomyopathies.


Subject(s)
Cardiomyopathies/etiology , Protein-Arginine N-Methyltransferases/physiology , RNA-Binding Proteins/metabolism , Sirtuin 1/physiology , Transcription Factors/metabolism , Vitamin B Deficiency/complications , Acetylation , Animals , Apoptosis/physiology , Cardiomyopathies/diagnostic imaging , Cardiomyopathies/metabolism , Cell Respiration/physiology , Energy Metabolism/physiology , Fatty Acids/metabolism , Female , Folic Acid/blood , Homocysteine/metabolism , Methylation , Mitochondria, Heart/metabolism , Oxidation-Reduction , PPAR alpha/metabolism , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha , Positron-Emission Tomography/methods , Proteomics/methods , Rats , Rats, Wistar , Receptors, Estrogen/metabolism , Stress, Physiological/physiology , ERRalpha Estrogen-Related Receptor
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