1  5334 148 QUADRICEPS MUSCLE WEAKNESS AND ATROPHY ARE ASSOCIATED WITH A DIFFERENTIAL EPIGENETIC PROFILE IN ADVANCED COPD. EPIGENETIC MECHANISMS REGULATE MUSCLE MASS AND FUNCTION IN MODELS OF MUSCLE DYSFUNCTION AND ATROPHY. WE ASSESSED WHETHER QUADRICEPS MUSCLE WEAKNESS AND ATROPHY ARE ASSOCIATED WITH A DIFFERENTIAL EXPRESSION PROFILE OF EPIGENETIC EVENTS IN PATIENTS WITH ADVANCED COPD (CHRONIC OBSTRUCTIVE PULMONARY DISEASE). IN VASTUS LATERALIS (VL) OF SEDENTARY SEVERE COPD PATIENTS (N=41), WHO WERE FURTHER SUBDIVIDED INTO THOSE WITH (N=25) AND WITHOUT (N=16) MUSCLE WEAKNESS AND HEALTHY CONTROLS (N=19), EXPRESSION OF MUSCLE-ENRICHED MIRNAS, HISTONE ACETYLTRANSFERASES (HATS) AND DEACETYLASES (HDACS), GROWTH AND ATROPHY SIGNALLING MARKERS, TOTAL PROTEIN AND HISTONE ACETYLATION, TRANSCRIPTION FACTORS, SMALL UBIQUITIN-RELATED MODIFIER (SUMO) LIGASES AND MUSCLE STRUCTURE WERE EXPLORED. ALL SUBJECTS WERE CLINICALLY EVALUATED. COMPARED WITH CONTROLS, IN VL OF ALL COPD TOGETHER AND IN MUSCLE-WEAKNESS PATIENTS, EXPRESSION OF MIR-1, MIR-206 AND MIR-27A, LEVELS OF LYSINE-ACETYLATED PROTEINS AND HISTONES AND ACETYLATED HISTONE 3 WERE INCREASED, WHEREAS EXPRESSION OF HDAC3, HDAC4, SIRTUIN-1 (SIRT-1), IGF-1 (INSULIN-LIKE GROWTH FACTOR-1) WERE DECREASED, AKT (V-AKT MURINE THYMOMA VIRAL ONCOGENE HOMOLOGUE 1) EXPRESSION DID NOT DIFFER, FOLLISTATIN EXPRESSION WAS GREATER, WHEREAS MYOSTATIN EXPRESSION WAS LOWER, SERUM REPONSE FACTOR (SRF) EXPRESSION WAS INCREASED AND FIBRE SIZE OF FAST-TWITCH FIBRES WAS SIGNIFICANTLY REDUCED. IN VL OF SEVERE COPD PATIENTS WITH MUSCLE WEAKNESS AND ATROPHY, EPIGENETIC EVENTS REGULATE MUSCLE DIFFERENTIATION RATHER THAN PROLIFERATION AND MUSCLE GROWTH AND ATROPHY SIGNALLING, PROBABLY AS FEEDBACK MECHANISMS TO PREVENT THOSE MUSCLES FROM UNDERGOING FURTHER ATROPHY. LYSINE-HYPERACETYLATION OF HISTONES MAY DRIVE ENHANCED PROTEIN CATABOLISM IN THOSE MUSCLES. THESE FINDINGS MAY HELP DESIGN NOVEL THERAPEUTIC STRATEGIES (ENHANCERS OF MIRNAS PROMOTING MYOGENESIS AND ACETYLATION INHIBITORS) TO SELECTIVELY TARGET MUSCLE WEAKNESS AND ATROPHY IN SEVERE COPD.	2015	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
2  5679  43 SHORT- AND LONG-TERM HINDLIMB IMMOBILIZATION AND RELOADING: PROFILE OF EPIGENETIC EVENTS IN GASTROCNEMIUS. SKELETAL MUSCLE DYSFUNCTION AND ATROPHY ARE CHARACTERISTIC FEATURES ACCOMPANYING CHRONIC CONDITIONS. EPIGENETIC EVENTS REGULATE MUSCLE MASS AND FUNCTION MAINTENANCE. WE HYPOTHESIZED THAT THE PATTERN OF EPIGENETIC EVENTS (MUSCLE-ENRICHED MICRORNAS AND HISTONE ACETYLATION) AND ACETYLATION OF TRANSCRIPTION FACTORS KNOWN TO SIGNAL MUSCLE WASTING MAY DIFFER BETWEEN EARLY- AND LATE-TIME POINTS IN SKELETAL MUSCLES OF MICE EXPOSED TO HINDLIMB IMMOBILIZATION (I) AND RECOVERY FOLLOWING I. BODY AND MUSCLE WEIGHTS, GRIP STRENGTH, MUSCLE-ENRICHED MICRORNAS, HISTONE DEACETYLASES (HDACS), ACETYLATION OF PROTEINS, HISTONES, AND TRANSCRIPTION FACTORS (TF), MYOGENIC TF FACTORS, AND MUSCLE PHENOTYPE WERE ASSESSED IN GASTROCNEMIUS OF MICE EXPOSED TO PERIODS (1, 2, 3, 7, 15, AND 30 DAYS, I GROUPS) OF HINDLIMB IMMOBILIZATION, AND IN THOSE EXPOSED TO RELOADING FOR DIFFERENT PERIODS OF TIME (1, 3, 7, 15, AND 30 DAYS, R GROUPS) FOLLOWING 7-DAY IMMOBILIZATION. COMPARED TO NON-IMMOBILIZED CONTROLS, MUSCLE WEIGHT, LIMB STRENGTH, MICRORNAS, ESPECIALLY MIR-486, SIRT1 LEVELS, AND SLOW- AND FAST-TWITCH CROSS-SECTIONAL AREAS WERE DECREASED IN MICE OF I GROUPS, WHEREAS PAX7 AND ACETYLATED FOXO1 AND FOXO3 LEVELS WERE INCREASED. MUSCLE RELOADING FOLLOWING SPLINT REMOVAL IMPROVED MUSCLE MASS LOSS, STRENGTH, AND FIBER ATROPHY, BY INCREASING MICRORNAS, PARTICULARLY MIR-486, AND SIRT1 CONTENT, WHILE DECREASING ACETYLATED FOXO1 AND FOXO3 LEVELS. IN THIS MOUSE MODEL OF DISUSE MUSCLE ATROPHY, MUSCLE-ENRICHED MICRORNAS, ESPECIALLY MIR-486, THROUGH PAX7 REGULATION DELAYED MUSCLE CELL DIFFERENTIATION FOLLOWING UNLOADING OF GASTROCNEMIUS MUSCLE. ACETYLATION OF FOXO1 AND 3 SEEMED TO DRIVE MUSCLE MASS LOSS AND ATROPHY, WHILE DEACETYLATION OF THESE FACTORS THROUGH SIRT1 WOULD ENABLE THE MUSCLE FIBERS TO REGENERATE. J. CELL. PHYSIOL. 232: 1415-1427, 2017. (C) 2016 WILEY PERIODICALS, INC.	2017	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
3  6232  25 THE LONG NONCODING RNA MEG3 REGULATES MYOBLAST PLASTICITY AND MUSCLE REGENERATION THROUGH EPITHELIAL-MESENCHYMAL TRANSITION. FORMATION OF SKELETAL MUSCLE IS AMONG THE MOST STRIKING EXAMPLES OF CELLULAR PLASTICITY IN ANIMAL TISSUE DEVELOPMENT, AND WHILE MUSCLE PROGENITOR CELLS ARE REPROGRAMMED BY EPITHELIAL-MESENCHYMAL TRANSITION (EMT) TO MIGRATE DURING EMBRYONIC DEVELOPMENT, THE REGULATION OF EMT IN POST-NATAL MYOGENESIS REMAINS POORLY UNDERSTOOD. HERE, WE DEMONSTRATE THAT THE LONG NONCODING RNA (LNCRNA) MEG3 REGULATES EMT IN MYOBLAST DIFFERENTIATION AND SKELETAL MUSCLE REGENERATION. CHRONIC INHIBITION OF MEG3 IN C2C12 MYOBLASTS INDUCED EMT, AND SUPPRESSED CELL STATE TRANSITIONS REQUIRED FOR DIFFERENTIATION. FURTHERMORE, ADENOVIRAL MEG3 KNOCKDOWN COMPROMISED MUSCLE REGENERATION, WHICH WAS ACCOMPANIED BY ABNORMAL MESENCHYMAL GENE EXPRESSION AND INTERSTITIAL CELL PROLIFERATION. TRANSCRIPTOMIC AND PATHWAY ANALYSES OF MEG3-DEPLETED C2C12 MYOBLASTS AND INJURED SKELETAL MUSCLE REVEALED A SIGNIFICANT DYSREGULATION OF EMT-RELATED GENES, AND IDENTIFIED TGFBETA AS A KEY UPSTREAM REGULATOR. IMPORTANTLY, INHIBITION OF TGFBETAR1 AND ITS DOWNSTREAM EFFECTORS, AND THE EMT TRANSCRIPTION FACTOR SNAI2, RESTORED MANY ASPECTS OF MYOGENIC DIFFERENTIATION IN MEG3-DEPLETED MYOBLASTS IN VITRO WE FURTHER DEMONSTRATE THAT REDUCTION OF MEG3-DEPENDENT EZH2 ACTIVITY RESULTS IN EPIGENETIC ALTERATIONS ASSOCIATED WITH TGFBETA ACTIVATION. THUS, MEG3 REGULATES MYOBLAST IDENTITY TO FACILITATE PROGRESSION INTO DIFFERENTIATION.	2021	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
4  2866  22 FUNCTIONAL ADULT ACETYLCHOLINE RECEPTOR DEVELOPS INDEPENDENTLY OF MOTOR INNERVATION IN SOL 8 MOUSE MUSCLE CELL LINE. WE HAVE DEFINED CULTURE CONDITIONS, USING A FEEDER LAYER OF CELLS FROM THE EMBRYONIC MESENCHYMAL CELL LINE, 10T1/2 AND A SERUM-FREE MEDIUM, WHICH ALLOW CELLS FROM THE MOUSE MYOGENIC CELL LINE SOL 8 TO FORM CONTRACTING MYOTUBES FOR TWO WEEKS. UNDER THESE CULTURE CONDITIONS, SOL 8 MYOTUBES UNDERGO A MATURATION PROCESS CHARACTERIZED BY A SEQUENTIAL EXPRESSION OF TWO PHENOTYPES. AN EARLY PHENOTYPE IS TYPIFIED BY THE EXPRESSION OF THE NICOTINIC ACETYLCHOLINE RECEPTOR (ACHR) GAMMA-SUBUNIT TRANSCRIPTS AND THE PRESENCE OF LOW CONDUCTANCE ACH-ACTIVATED CHANNELS, TYPICAL OF EMBRYONIC ACHR. A LATE PHENOTYPE IS CHARACTERIZED BY THE EXPRESSION OF ACHR EPSILON-SUBUNIT TRANSCRIPTS, THE DECREASED ACCUMULATION OF GAMMA-SUBUNIT TRANSCRIPTS AND THE APPEARANCE OF HIGH CONDUCTANCE ACH-ACTIVATED CHANNELS, TYPICAL OF ADULT ACHR. THESE RESULTS INDICATE THAT THE EXPRESSION OF FUNCTIONAL ADULT TYPE ACHR DOES NOT REQUIRE THE PRESENCE OF THE MOTOR NERVE AND THEREFORE REPRESENTS AN INTRINSIC FEATURE OF THE SOL 8 MUSCLE CELLS. CHRONIC EXPOSURE OF THE CELLS TO THE VOLTAGE-SENSITIVE NA+ CHANNEL BLOCKING AGENT TETRODOTOXIN DOES NOT AFFECT THE APPEARANCE OF THE ACHR EPSILON-SUBUNIT TRANSCRIPTS BUT PREVENTS THE REDUCTION OF THE STEADY-STATE LEVEL OF THE ACHR GAMMA-SUBUNIT TRANSCRIPTS AND YIELDS A REDUCED PROPORTION OF THE ADULT TYPE CHANNELS. THUS, ACTIVITY SEEMS TO FACILITATE THE SWITCH FROM THE EMBRYONIC TO THE ADULT PHENOTYPE OF THE ACHR PROTEIN. THE SOL 8 CELL SYSTEM MIGHT BE USEFUL TO ANALYSE FURTHER THE GENETIC AND EPIGENETIC REGULATION OF MUSCLE FIBRE MATURATION IN MAMMALS.	1991	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
5  3633  31 INCREASE IN HDAC9 SUPPRESSES MYOBLAST DIFFERENTIATION VIA EPIGENETIC REGULATION OF AUTOPHAGY IN HYPOXIA. EXTREMELY REDUCED OXYGEN (O(2)) LEVELS ARE DETRIMENTAL TO MYOGENIC DIFFERENTIATION AND MULTINUCLEATED MYOTUBE FORMATION, AND CHRONIC EXPOSURE TO HIGH-ALTITUDE HYPOXIA HAS BEEN REPORTED TO BE AN IMPORTANT FACTOR IN SKELETAL MUSCLE ATROPHY. HOWEVER, HOW CHRONIC HYPOXIA CAUSES MUSCLE DYSFUNCTION REMAINS UNKNOWN. IN THE PRESENT STUDY, WE FOUND THAT SEVERE HYPOXIA (1% O(2)) SIGNIFICANTLY INHIBITED THE FUNCTION OF C2C12 CELLS (FROM A MYOBLAST CELL LINE). IMPORTANTLY, THE IMPAIRMENT WAS CONTINUOUSLY MANIFESTED EVEN DURING CULTURE UNDER NORMOXIC CONDITIONS FOR SEVERAL PASSAGES. MECHANISTICALLY, WE REVEALED THAT HISTONE DEACETYLASES 9 (HDAC9), A MEMBER OF THE HISTONE DEACETYLASE FAMILY, WAS SIGNIFICANTLY INCREASED IN C2C12 CELLS UNDER HYPOXIC CONDITIONS, THEREBY INHIBITING INTRACELLULAR AUTOPHAGY LEVELS BY DIRECTLY BINDING TO THE PROMOTER REGIONS OF ATG7, BECLIN1, AND LC3. THIS PHENOMENON RESULTED IN THE SEQUENTIAL DEPHOSPHORYLATION OF GSK3BETA AND INACTIVATION OF THE CANONICAL WNT PATHWAY, IMPAIRING THE FUNCTION OF THE C2C12 CELLS. TAKEN TOGETHER, OUR RESULTS SUGGEST THAT HYPOXIA-INDUCED MYOBLAST DYSFUNCTION IS DUE TO ABERRANT EPIGENETIC REGULATION OF AUTOPHAGY, AND OUR EXPERIMENTAL EVIDENCE REVEALS THE POSSIBLE MOLECULAR PATHOGENESIS RESPONSIBLE FOR SOME MUSCLE DISEASES CAUSED BY CHRONIC HYPOXIA AND SUGGESTS A POTENTIAL THERAPEUTIC OPTION.	2019	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
6  1475  15 DISTRIBUTION OF H3K27ME3, H3K9ME3, AND H3K4ME3 ALONG AUTOPHAGY-RELATED GENES HIGHLY EXPRESSED IN STARVED ZEBRAFISH MYOTUBES. THE ZEBRAFISH (DANIO RERIO) REMAINS THE TELEOST FISH OF CHOICE FOR BIOLOGICAL INVESTIGATIONS DUE TO THE VAST ARRAY OF MOLECULAR TOOLS AND RESOURCES AVAILABLE. TO BETTER UNDERSTAND THE EPIGENETIC REGULATION OF AUTOPHAGY, WE UTILIZED A PRIMARY MYOTUBE CULTURE SYSTEM GENERATED FROM ISOLATED MYOGENIC PRECURSOR CELLS (MPCS) FROM ZEBRAFISH GROWN UNDER STARVATION CONDITIONS USING A MEDIA DEVOID OF SERUM AND AMINO ACIDS. HERE, WE REPORT STARVATION-INDUCED REGULATION OF SEVERAL AUTOPHAGY-RELATED GENES (ATG) EXPRESSION AND PROFILE THE DISTRIBUTION OF H3K27ME3, H3K9ME3, AND H3K4ME3 MARKS ALONG LC3B, ATG4B AND P62/SQSTM1 LOCI. THESE DATA SUPPORT EPIGENETIC REGULATION OF AUTOPHAGY IN RESPONSE TO STARVATION THAT SUGGESTS A LEVEL OF REGULATION THAT CAN BE SUSTAINED FOR CHRONIC CONDITIONS VIA CHROMATIN MODIFICATION.	2017	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
7  4544  34 MUSCLE HYPERTROPHY IN HYPOXIA WITH INFLAMMATION IS CONTROLLED BY BROMODOMAIN AND EXTRA-TERMINAL DOMAIN PROTEINS. SOME OF THE CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) PATIENTS ENGAGED IN EXERCISE-BASED MUSCLE REHABILITATION PROGRAMS ARE UNRESPONSIVE. TO UNRAVEL THE RESPECTIVE ROLE OF CHRONIC HYPOXIA AND PULMONARY INFLAMMATION ON SOLEUS MUSCLE HYPERTROPHIC CAPACITIES, WE CHALLENGED MALE WISTAR RATS TO REPEATED LIPOPOLYSACCHARIDE INSTILLATIONS, ASSOCIATED OR NOT WITH A CHRONIC HYPOXIA EXPOSURE. MUSCLE HYPERTROPHY WAS INITIATED BY BILATERAL ABLATION OF SOLEUS AGONISTS 1 WEEK BEFORE SACRIFICE. TO UNDERSTAND THE ROLE PLAYED BY THE HISTONE ACETYLATION, WE ALSO TREATED OUR ANIMALS WITH AN INHIBITOR OF BROMODOMAINS AND EXTRA TERMINAL PROTEINS (I-BET) DURING THE WEEK AFTER SURGERY. PULMONARY INFLAMMATION TOTALLY INHIBITED THIS HYPERTROPHY RESPONSE UNDER BOTH NORMOXIC AND HYPOXIC CONDITIONS (26% LOWER THAN CONTROL SURGERY, P < 0.05), CONSISTENT WITH THE S6K1 AND MYOGENIN MEASUREMENTS. CHANGES IN HISTONE ACETYLATION AND CLASS IIA HISTONE DEACETYLASES EXPRESSION, FOLLOWING PULMONARY INFLAMMATION, SUGGESTED A PUTATIVE ROLE FOR HISTONE ACETYLATION SIGNALING IN THE ALTERED HYPERTROPHY RESPONSE. THE I-BET DRUG RESTORED THE HYPERTROPHY RESPONSE SUGGESTING THAT THE NON-RESPONSE OF MUSCLE TO A HYPERTROPHIC STIMULUS COULD BE MODULATED BY EPIGENETIC MECHANISMS, INCLUDING HISTONE-ACETYLATION DEPENDANT PATHWAYS. DRUGS TARGETING SUCH EPIGENETIC MECHANISMS MAY OPEN THERAPEUTIC PERSPECTIVES FOR COPD PATIENTS WITH SYSTEMIC INFLAMMATION WHO ARE UNRESPONSIVE TO REHABILITATION.	2017	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
8  2786  23 EZH2 RESTRICTS THE SMOOTH MUSCLE LINEAGE DURING MOUSE LUNG MESOTHELIAL DEVELOPMENT. DURING DEVELOPMENT, THE LUNG MESODERM GENERATES A VARIETY OF CELL LINEAGES, INCLUDING AIRWAY AND VASCULAR SMOOTH MUSCLE. EPIGENETIC CHANGES IN ADULT LUNG MESODERMAL LINEAGES ARE THOUGHT TO CONTRIBUTE TOWARDS DISEASES SUCH AS IDIOPATHIC PULMONARY FIBROSIS AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE, ALTHOUGH THE FACTORS THAT REGULATE EARLY LUNG MESODERM DEVELOPMENT ARE UNKNOWN. WE SHOW IN MOUSE THAT THE PRC2 COMPONENT EZH2 IS REQUIRED TO RESTRICT SMOOTH MUSCLE DIFFERENTIATION IN THE DEVELOPING LUNG MESOTHELIUM. MESODERMAL LOSS OF EZH2 LEADS TO THE FORMATION OF ECTOPIC SMOOTH MUSCLE IN THE SUBMESOTHELIAL REGION OF THE DEVELOPING LUNG MESODERM. LOSS OF EZH2 SPECIFICALLY IN THE DEVELOPING MESOTHELIUM REVEALS A MESOTHELIAL CELL-AUTONOMOUS ROLE FOR EZH2 IN REPRESSION OF THE SMOOTH MUSCLE DIFFERENTIATION PROGRAM. LOSS OF EZH2 DEREPRESSES EXPRESSION OF MYOCARDIN AND TBX18, WHICH ARE IMPORTANT REGULATORS OF SMOOTH MUSCLE DIFFERENTIATION FROM THE MESOTHELIUM AND RELATED CELL LINEAGES. TOGETHER, THESE FINDINGS UNCOVER AN EZH2-DEPENDENT MECHANISM TO RESTRICT THE SMOOTH MUSCLE GENE EXPRESSION PROGRAM IN THE DEVELOPING MESOTHELIUM AND ALLOW APPROPRIATE CELL FATE DECISIONS TO OCCUR IN THIS MULTIPOTENT MESODERM LINEAGE.	2016	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
9  1633  71 DO EPIGENETIC EVENTS TAKE PLACE IN THE VASTUS LATERALIS OF PATIENTS WITH MILD CHRONIC OBSTRUCTIVE PULMONARY DISEASE? MUSCLE DYSFUNCTION IS A MAJOR COMORBIDITY IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). SEVERAL BIOLOGICAL MECHANISMS INCLUDING EPIGENETIC EVENTS REGULATE MUSCLE MASS AND FUNCTION IN MODELS OF MUSCLE ATROPHY. INVESTIGATIONS CONDUCTED SO FAR HAVE FOCUSED ON THE ELUCIDATION OF BIOLOGICAL MECHANISMS INVOLVED IN MUSCLE DYSFUNCTION IN ADVANCED COPD. WE ASSESSED WHETHER THE EPIGENETIC PROFILE MAY BE ALTERED IN THE VASTUS LATERALIS OF PATIENTS WITH MILD COPD, NORMAL BODY COMPOSITION, AND MILDLY IMPAIRED MUSCLE FUNCTION AND EXERCISE CAPACITY. IN VASTUS LATERALIS (VL) OF MILD COPD PATIENTS WITH WELL-PRESERVED BODY COMPOSITION AND IN HEALTHY AGE-MATCHED CONTROLS, EXPRESSION OF DNA METHYLATION, MUSCLE-ENRICHED MICRORNAS, HISTONE ACETYLTRANSFERASES (HTAS) AND DEACETYLASES (HDACS), PROTEIN ACETYLATION, SMALL UBIQUITIN-RELATED MODIFIER (SUMO) LIGASES, AND MUSCLE STRUCTURE WERE EXPLORED. ALL SUBJECTS WERE CLINICALLY EVALUATED. COMPARED TO HEALTHY CONTROLS, IN THE VL OF MILD COPD PATIENTS, MUSCLE FUNCTION AND EXERCISE CAPACITY WERE MODERATELY REDUCED, DNA METHYLATION LEVELS DID NOT DIFFER, MIR-1 EXPRESSION LEVELS WERE INCREASED AND POSITIVELY CORRELATED WITH BOTH FORCED EXPIRATORY VOLUME IN ONE SECOND (FEV1) AND QUADRICEPS FORCE, HDAC4 PROTEIN LEVELS WERE INCREASED, AND MUSCLE FIBER TYPES AND SIZES WERE NOT DIFFERENT. MODERATE SKELETAL MUSCLE DYSFUNCTION IS A RELEVANT FEATURE IN PATIENTS WITH MILD COPD AND PRESERVED BODY COMPOSITION. SEVERAL EPIGENETIC EVENTS ARE DIFFERENTIALLY EXPRESSED IN THE LIMB MUSCLES OF THESE PATIENTS, PROBABLY AS AN ATTEMPT TO COUNTERBALANCE THE UNDERLYING MECHANISMS THAT ALTER MUSCLE FUNCTION AND MASS. THE STUDY OF PATIENTS AT EARLY STAGES OF THEIR DISEASE IS OF INTEREST AS THEY ARE A TARGET FOR TIMELY THERAPEUTIC INTERVENTIONS THAT MAY SLOW DOWN THE COURSE OF THE DISEASE AND PREVENT THE DELETERIOUS EFFECTS OF MAJOR COMORBIDITIES.	2014	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
10  4841  37 ONE WEEK, BUT NOT 12 HOURS, OF CAST IMMOBILIZATION ALTERS PROMOTOR DNA METHYLATION PATTERNS IN THE NNOS GENE IN MOUSE SKELETAL MUSCLE. KEY POINTS: DNA METHYLATION MAY PLAY AN IMPORTANT ROLE IN REGULATING GENE EXPRESSION IN SKELETAL MUSCLE TO ADAPT TO PHYSICAL ACTIVITY AND INACTIVITY. NEURONAL NITRIC OXIDE SYNTHASE (NNOS) IN SKELETAL MUSCLE IS A KEY REGULATOR OF SKELETAL MUSCLE MASS; HOWEVER, IT IS UNCLEAR WHETHER NNOS EXPRESSION IS REGULATED BY DNA METHYLATION. WE FOUND THAT 1 WEEK OF CAST IMMOBILIZATION INCREASED NNOS DNA METHYLATION LEVELS AND DOWNREGULATED NNOS GENE EXPRESSION IN ATROPHIC SLOW-TWITCH SOLEUS MUSCLE FROM THE MOUSE LEG. THESE CHANGES WERE NOT DETECTED IN NON-ATROPHIC FAST-TWITCH EXTENSOR DIGITORUM LONGUS MUSCLE. TWELVE HOURS OF CAST IMMOBILIZATION DECREASED NNOS GENE EXPRESSION, WHEREAS NNOS DNA METHYLATION LEVELS WERE UNCHANGED, SUGGESTING THAT DOWNREGULATION OF NNOS GENE EXPRESSION BY SHORT-TERM MUSCLE INACTIVITY IS INDEPENDENT OF THE DNA METHYLATION PATTERN. THESE FINDINGS CONTRIBUTE TO A BETTER UNDERSTANDING OF THE MAINTENANCE OF SKELETAL MUSCLE MASS AND PREVENTION OF MUSCLE ATROPHY BY EPIGENETIC MECHANISMS VIA THE NNOS/NO PATHWAY. ABSTRACT: DNA METHYLATION IS A MECHANISM THAT CONTROLS GENE EXPRESSION IN SKELETAL MUSCLE UNDER VARIOUS ENVIRONMENTAL STIMULI, SUCH AS PHYSICAL ACTIVITY AND INACTIVITY. NEURONAL NITRIC OXIDE SYNTHASE (NNOS) REGULATES MUSCLE ATROPHY IN SKELETAL MUSCLE. HOWEVER, THE MECHANISMS REGULATING NNOS EXPRESSION IN ATROPHIC MUSCLE REMAIN UNCLEAR. WE HYPOTHESIZED THAT NNOS EXPRESSION IN ATROPHIC MUSCLE IS REGULATED BY DNA METHYLATION OF THE NNOS PROMOTOR IN SOLEUS (SOL; SLOW-TWITCH FIBRE DOMINANT) AND EXTENSOR DIGITORUM LONGUS (EDL; FAST-TWITCH FIBRE DOMINANT) MUSCLES. ONE WEEK OF CAST IMMOBILIZATION INDUCED SIGNIFICANT MUSCLE ATROPHY IN SOL BUT NOT IN EDL. WE SHOWED THAT 1 WEEK OF CAST IMMOBILIZATION INCREASED NNOS DNA METHYLATION LEVELS IN SOL, ALTHOUGH ONLY A MINOR CHANGE WAS DETECTED IN EDL. CONSISTENT WITH THE INCREASED DNA METHYLATION LEVELS IN ATROPHIC SOL, THE GENE EXPRESSION LEVELS OF TOTAL NNOS AND NNOSMICRO (I.E. THE MAJOR SPLICING VARIANT OF NNOS IN SKELETAL MUSCLE) DECREASED. THE ABUNDANCE OF THE NNOS PROTEIN AND CELL MEMBRANE (ESPECIALLY TYPE IIA FIBRE) IMMUNOREACTIVITY ALSO DECREASED IN ATROPHIC SOL. THESE CHANGES WERE NOT OBSERVED IN EDL AFTER 1 WEEK OF CAST IMMOBILIZATION. FURTHERMORE, DESPITE THE LACK OF SIGNIFICANT ATROPHY, 12 H OF CAST IMMOBILIZATION DECREASED GENE EXPRESSION LEVELS OF TOTAL NNOS AND NNOSMICRO IN SOL. HOWEVER, NO ASSOCIATION WAS DETECTED BETWEEN NNOS DNA METHYLATION AND GENE EXPRESSION. THE EXPRESSION OF THE NNOSBETA GENE, ANOTHER SPLICING VARIANT OF NNOS, IN EDL WAS UNCHANGED BY CAST IMMOBILIZATION, WHEREAS ITS EXPRESSION WAS NOT DETECTED IN SOL. WE CONCLUDED THAT CHRONIC ADAPTATION OF NNOS GENE EXPRESSION IN CAST IMMOBILIZED MUSCLE MAY INVOLVE NNOS DNA METHYLATION.	2019	

11   169  32 ABNORMALITIES OF AMPK ACTIVATION AND GLUCOSE UPTAKE IN CULTURED SKELETAL MUSCLE CELLS FROM INDIVIDUALS WITH CHRONIC FATIGUE SYNDROME. BACKGROUND: POST EXERTIONAL MUSCLE FATIGUE IS A KEY FEATURE IN CHRONIC FATIGUE SYNDROME (CFS). ABNORMALITIES OF SKELETAL MUSCLE FUNCTION HAVE BEEN IDENTIFIED IN SOME BUT NOT ALL PATIENTS WITH CFS. TO TRY TO LIMIT POTENTIAL CONFOUNDERS THAT MIGHT CONTRIBUTE TO THIS CLINICAL HETEROGENEITY, WE DEVELOPED A NOVEL IN VITRO SYSTEM THAT ALLOWS COMPARISON OF AMP KINASE (AMPK) ACTIVATION AND METABOLIC RESPONSES TO EXERCISE IN CULTURED SKELETAL MUSCLE CELLS FROM CFS PATIENTS AND CONTROL SUBJECTS. METHODS: SKELETAL MUSCLE CELL CULTURES WERE ESTABLISHED FROM 10 SUBJECTS WITH CFS AND 7 AGE-MATCHED CONTROLS, SUBJECTED TO ELECTRICAL PULSE STIMULATION (EPS) FOR UP TO 24H AND EXAMINED FOR CHANGES ASSOCIATED WITH EXERCISE. RESULTS: IN THE BASAL STATE, CFS CULTURES SHOWED INCREASED MYOGENIN EXPRESSION BUT DECREASED IL6 SECRETION DURING DIFFERENTIATION COMPARED WITH CONTROL CULTURES. CONTROL CULTURES SUBJECTED TO 16 H EPS SHOWED A SIGNIFICANT INCREASE IN BOTH AMPK PHOSPHORYLATION AND GLUCOSE UPTAKE COMPARED WITH UNSTIMULATED CELLS. IN CONTRAST, CFS CULTURES SHOWED NO INCREASE IN AMPK PHOSPHORYLATION OR GLUCOSE UPTAKE AFTER 16 H EPS. HOWEVER, GLUCOSE UPTAKE REMAINED RESPONSIVE TO INSULIN IN THE CFS CELLS POINTING TO AN EXERCISE-RELATED DEFECT. IL6 SECRETION IN RESPONSE TO EPS WAS SIGNIFICANTLY REDUCED IN CFS COMPARED WITH CONTROL CULTURES AT ALL TIME POINTS MEASURED. CONCLUSION: EPS IS AN EFFECTIVE MODEL FOR ELICITING MUSCLE CONTRACTION AND THE METABOLIC CHANGES ASSOCIATED WITH EXERCISE IN CULTURED SKELETAL MUSCLE CELLS. WE FOUND FOUR MAIN DIFFERENCES IN CULTURED SKELETAL MUSCLE CELLS FROM SUBJECTS WITH CFS; INCREASED MYOGENIN EXPRESSION IN THE BASAL STATE, IMPAIRED ACTIVATION OF AMPK, IMPAIRED STIMULATION OF GLUCOSE UPTAKE AND DIMINISHED RELEASE OF IL6. THE RETENTION OF THESE DIFFERENCES IN CULTURED MUSCLE CELLS FROM CFS SUBJECTS POINTS TO A GENETIC/EPIGENETIC MECHANISM, AND PROVIDES A SYSTEM TO IDENTIFY NOVEL THERAPEUTIC TARGETS.	2015	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
12  4875  28 OVEREXPRESSION OF AKT1 ENHANCES ADIPOGENESIS AND LEADS TO LIPOMA FORMATION IN ZEBRAFISH. BACKGROUND: OBESITY IS A COMPLEX, MULTIFACTORIAL DISORDER INFLUENCED BY THE INTERACTION OF GENETIC, EPIGENETIC, AND ENVIRONMENTAL FACTORS. OBESITY INCREASES THE RISK OF CONTRACTING MANY CHRONIC DISEASES OR METABOLIC SYNDROME. RESEARCHERS HAVE ESTABLISHED SEVERAL MAMMALIAN MODELS OF OBESITY TO STUDY ITS UNDERLYING MECHANISM. HOWEVER, A LOWER VERTEBRATE MODEL FOR CONVENIENTLY PERFORMING DRUG SCREENING AGAINST OBESITY REMAINS ELUSIVE. THE SPECIFIC AIM OF THIS STUDY WAS TO CREATE A ZEBRAFISH OBESITY MODEL BY OVER EXPRESSING THE INSULIN SIGNALING HUB OF THE AKT1 GENE. METHODOLOGY/PRINCIPAL FINDINGS: SKIN ONCOGENIC TRANSFORMATION SCREENING SHOWS THAT A STABLE ZEBRAFISH TRANSGENIC OF TG(KRT4HSA.MYRAKT1)(CY18) DISPLAYS SEVERELY OBESE PHENOTYPES AT THE ADULT STAGE. IN TG(KRT4:HSA.MYRAKT1)(CY18), THE EXPRESSION OF EXOGENOUS HUMAN CONSTITUTIVELY ACTIVE AKT1 (MYRAKT1) CAN ACTIVATE ENDOGENOUS DOWNSTREAM TARGETS OF MTOR, GSK-3ALPHA/BETA, AND 70S6K. DURING THE EMBRYONIC TO LARVAL TRANSITORY PHASE, THE SPECIFIC OVER EXPRESSION OF MYRAKT1 IN SKIN CAN PROMOTE HYPERTROPHIC AND HYPERPLASTIC GROWTH. FROM 21 HOUR POST-FERTILIZATION (HPF) ONWARDS, MYRAKT1 TRANSGENE WAS ECTOPICALLY EXPRESSED IN SEVERAL MESENCHYMAL DERIVED TISSUES. THIS MAY BE THE RESULT OF THE INTEGRATION POSITION EFFECT. TG(KRT4:HSA.MYRAKT1)(CY18) CAUSED A RAPID INCREASE OF BODY WEIGHT, HYPERPLASTIC GROWTH OF ADIPOCYTES, ABNORMAL ACCUMULATION OF FAT TISSUES, AND BLOOD GLUCOSE INTOLERANCE AT THE ADULT STAGE. REAL-TIME RT-PCR ANALYSIS SHOWED THE MAJORITY OF KEY GENES ON REGULATING ADIPOGENESIS, ADIPOCYTOKINE, AND INFLAMMATION ARE HIGHLY UPREGULATED IN TG(KRT4:HSA.MYRAKT1)(CY18). IN CONTRAST, THE MYOGENESIS- AND SKELETOGENESIS-RELATED GENE TRANSCRIPTS ARE SIGNIFICANTLY DOWNREGULATED IN TG(KRT4:HSA.MYRAKT1)(CY18), SUGGESTING THAT EXCESS ADIPOCYTE DIFFERENTIATION OCCURS AT THE EXPENSE OF OTHER MESENCHYMAL DERIVED TISSUES. CONCLUSION/SIGNIFICANCE: COLLECTIVELY, THE FINDINGS OF THIS STUDY PROVIDE DIRECT EVIDENCE THAT AKT1 SIGNALING PLAYS AN IMPORTANT ROLE IN BALANCING NORMAL LEVELS OF FAT TISSUE IN VIVO. THE OBESE ZEBRAFISH EXAMINED IN THIS STUDY COULD BE A NEW POWERFUL MODEL TO SCREEN NOVEL DRUGS FOR THE TREATMENT OF HUMAN OBESITY.	2012	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
13  3519  32 IGF-1 SIGNALING IN NEONATAL HYPOXIA-INDUCED PULMONARY HYPERTENSION: ROLE OF EPIGENETIC REGULATION. PULMONARY HYPERTENSION IS A FATAL DISEASE CHARACTERIZED BY A PROGRESSIVE INCREASE IN PULMONARY ARTERY PRESSURE ACCOMPANIED BY PULMONARY VASCULAR REMODELING AND INCREASED VASOMOTOR TONE. ALTHOUGH SOME BIOLOGICAL PATHWAYS HAVE BEEN IDENTIFIED IN NEONATAL HYPOXIA-INDUCED PULMONARY HYPERTENSION (PH), LITTLE IS KNOWN REGARDING THE ROLE OF GROWTH FACTORS IN THE PATHOGENESIS OF PH IN NEONATES. IN THIS STUDY, USING A MODEL OF HYPOXIA-INDUCED PH IN NEONATAL MICE, WE DEMONSTRATE THAT THE GROWTH FACTOR INSULIN-LIKE GROWTH FACTOR-1 (IGF-1), A POTENT ACTIVATOR OF THE AKT SIGNALING PATHWAY, IS INVOLVED IN NEONATAL PH. AFTER EXPOSURE TO HYPOXIA, IGF-1 SIGNALING IS ACTIVATED IN PULMONARY ENDOTHELIAL AND SMOOTH MUSCLE CELLS IN VITRO, AND THE IGF-1 DOWNSTREAM SIGNAL PAKT(S473) IS UPREGULATED IN LUNGS OF NEONATAL MICE. WE FOUND THAT IGF-1 REGULATES ET-1 EXPRESSION IN PULMONARY ENDOTHELIAL CELLS AND THAT IGF-1 EXPRESSION IS REGULATED BY HISTONE DEACETYLASES (HDACS). IN ADDITION, THERE IS A DIFFERENTIAL CYTOSINE METHYLATION SITE IN THE IGF-1 PROMOTER REGION IN RESPONSE TO NEONATAL HYPOXIA. MOREOVER, INHIBITION OF HDACS WITH APICIDIN DECREASES NEONATAL HYPOXIA-INDUCED GLOBAL DNA METHYLATION LEVELS IN LUNGS AND SPECIFIC CYTOSINE METHYLATION LEVELS AROUND THE PULMONARY IGF-1 PROMOTER REGION. FINALLY, HDAC INHIBITION WITH APICIDIN REDUCES CHRONIC HYPOXIA-INDUCED ACTIVATION OF IGF-1/PAKT SIGNALING IN LUNGS AND ATTENUATES RIGHT VENTRICULAR HYPERTROPHY AND PULMONARY VASCULAR REMODELING. TAKEN TOGETHER, WE CONCLUDE THAT IGF-1, WHICH IS EPIGENETICALLY REGULATED, IS INVOLVED IN THE PATHOGENESIS OF PULMONARY HYPERTENSION IN NEONATAL MICE. THIS STUDY IMPLICATES A NOVEL HDAC/IGF-1 EPIGENETIC PATHWAY IN THE REGULATION OF HYPOXIA-INDUCED PH AND WARRANTS FURTHER STUDY OF THE ROLE OF IGF-1 IN NEONATAL PULMONARY HYPERTENSIVE DISEASE.	2015	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
14  4576  34 MYOGENIC POTENTIAL OF CANINE CRANIOFACIAL SATELLITE CELLS. THE SKELETAL FIBERS HAVE DIFFERENT EMBRYOLOGICAL ORIGIN; THE EXTRAOCULAR AND JAW-CLOSER MUSCLES DEVELOP FROM PRECHORDAL MESODERM WHILE THE LIMB AND TRUNK MUSCLES FROM SOMITES. THESE DIFFERENT ORIGINS CHARACTERIZE ALSO THE ADULT MUSCLE STEM CELLS, KNOWN AS SATELLITE CELLS (SCS) AND RESPONSIBLE FOR THE FIBER GROWTH AND REGENERATION. THE PHYSIOLOGICAL PROPERTIES OF PRESOMITIC SCS AND THEIR EPIGENETICS ARE POORLY STUDIED DESPITE THEIR PECULIAR CHARACTERISTICS TO PRESERVE MUSCLE INTEGRITY DURING CHRONIC MUSCLE DEGENERATION. HERE, WE ISOLATED SCS FROM CANINE SOMITIC [SOMITE-DERIVED MUSCLE (SDM): VASTUS LATERALIS, RECTUS ABDOMINIS, GLUTEUS SUPERFICIALIS, BICEPS FEMORIS, PSOAS] AND PRESOMITIC [PRE-SOMITE-DERIVED MUSCLE (PSDM): LATERAL RECTUS, TEMPORALIS, AND RETRACTOR BULBI] MUSCLES AS MYOGENIC PROGENITOR CELLS FROM YOUNG AND OLD ANIMALS. IN ADDITION, SDM AND PSDM-SCS WERE OBTAINED ALSO FROM GOLDEN RETRIEVERS AFFECTED BY MUSCULAR DYSTROPHY (GRMD). WE CHARACTERIZED THE LIFESPAN, THE MYOGENIC POTENTIAL AND FUNCTIONS, AND OXIDATIVE STRESS OF BOTH SOMITIC AND PRESOMITIC SCS WITH THE AIM TO REVEAL DIFFERENCES WITH AGING AND BETWEEN HEALTHY AND DYSTROPHIC ANIMALS. THE DIFFERENT PROLIFERATION RATE WAS CONSISTENT WITH HIGHER TELOMERASE ACTIVITY IN PSDM-SCS COMPARED TO SDM-SCS, ALTHOUGH RESTRICTED AT EARLY PASSAGES. SDM-SCS EXPRESS EARLY (PAX7, MYOD) AND LATE (MYOSIN HEAVY CHAIN, MYOGENIN) MYOGENIC MARKERS DIFFERENTLY FROM PSDM-SCS RESULTING IN A MORE EFFICIENT AND FASTER CELL DIFFERENTIATION. TAKEN TOGETHER, OUR RESULTS SHOWED THAT PSDM-SCS ELICIT A STRONGER STEM CELL PHENOTYPE COMPARED TO SDM ONES. FINALLY, MYOMIR EXPRESSION PROFILE REVEALS A UNIQUE EPIGENETIC SIGNATURE IN GRMD SCS AND MIR-206, HIGHLY EXPRESSED IN DYSTROPHIC SCS, SEEMS TO PLAY A CRITICAL ROLE IN MUSCLE DEGENERATION. THUS, MIR-206 COULD REPRESENT A POTENTIAL TARGET FOR NOVEL THERAPEUTIC APPROACHES.	2014	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
15  6757  28 WNT SIGNALING IN LIVER FIBROSIS: PROGRESS, CHALLENGES AND POTENTIAL DIRECTIONS. LIVER FIBROSIS IS A COMMON WOUND-HEALING RESPONSE TO CHRONIC LIVER INJURIES, INCLUDING ALCOHOLIC OR DRUG TOXICITY, PERSISTENT VIRAL INFECTION, AND GENETIC FACTORS. MYOFIBROBLASTIC TRANSDIFFERENTIATION (MTD) IS THE PIVOTAL EVENT DURING LIVER FIBROGENESIS, AND RESEARCH IN THE PAST FEW YEARS HAS IDENTIFIED KEY MEDIATORS AND MOLECULAR MECHANISMS RESPONSIBLE FOR MTD OF HEPATIC STELLATE CELLS (HSCS). HSCS ARE UNDIFFERENTIATED CELLS WHICH PLAY AN IMPORTANT ROLE IN LIVER REGENERATION. RECENT EVIDENCE DEMONSTRATES THAT HSCS DERIVE FROM MESODERM AND AT LEAST IN PART VIA SEPTUM TRANSVERSUM AND MESOTHELIUM, AND HSCS EXPRESS MARKERS FOR DIFFERENT CELL TYPES WHICH DERIVE FROM MULTIPOTENT MESENCHYMAL PROGENITORS. THERE IS A REGULATORY COMMONALITY BETWEEN DIFFERENTIATION OF ADIPOCYTES AND THAT OF HSC, AND THE SHIFT FROM ADIPOGENIC TO MYOGENIC OR NEURONAL PHENOTYPE CHARACTERIZES HSC MTD. CENTRAL OF THIS SHIFT IS A LOSS OF EXPRESSION OF THE MASTER ADIPOGENIC REGULATOR PEROXISOME PROLIFERATOR ACTIVATED RECEPTOR GAMMA (PPARGAMMA). RESTORED EXPRESSION OF PPARGAMMA AND/OR OTHER ADIPOGENIC TRANSCRIPTION GENES CAN REVERSE MYOFIBROBLASTIC HSCS TO DIFFERENTIATED CELLS. VERTEBRATE WNT AND DROSOPHILA WINGLESS ARE HOMOLOGOUS GENES, AND THEIR TRANSLATED PROTEINS HAVE BEEN SHOWN TO PARTICIPATE IN THE REGULATION OF CELL PROLIFERATION, CELL POLARITY, CELL DIFFERENTIATION, AND OTHER BIOLOGICAL ROLES. MORE RECENTLY, WNT SIGNALING IS IMPLICATED IN HUMAN FIBROSING DISEASES, SUCH AS PULMONARY FIBROSIS, RENAL FIBROSIS, AND LIVER FIBROSIS. BLOCKING THE CANONICAL WNT SIGNAL PATHWAY WITH THE CO-RECEPTOR ANTAGONIST DICKKOPF-1 (DKK1) ABROGATES THESE EPIGENETIC REPRESSIONS AND RESTORES THE GENE PPARGAMMA EXPRESSION AND HSC DIFFERENTIATION. THE IDENTIFIED MORPHOGEN MEDIATED EPIGENETIC REGULATION OF PPARGAMMA AND HSC DIFFERENTIATION ALSO SERVES AS NOVEL THERAPEUTIC TARGETS FOR LIVER FIBROSIS AND LIVER REGENERATION. IN CONCLUSION, THE WNT SIGNALING PROMOTES LIVER FIBROSIS BY ENHANCING HSC ACTIVATION AND SURVIVAL, AND WE HEREIN DISCUSS WHAT WE CURRENTLY KNOW AND WHAT WE EXPECT WILL COME IN THIS FIELD IN THE NEXT FUTURE.	2013	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
16  4577  33 MYOSTATIN: BASIC BIOLOGY TO CLINICAL APPLICATION. MYOSTATIN IS A MEMBER OF THE TRANSFORMING GROWTH FACTOR (TGF)-BETA SUPERFAMILY. IT IS EXPRESSED BY ANIMAL AND HUMAN SKELETAL MUSCLE CELLS WHERE IT LIMITS MUSCLE GROWTH AND PROMOTES PROTEIN BREAKDOWN. ITS EFFECTS ARE INFLUENCED BY COMPLEX MECHANISMS INCLUDING TRANSCRIPTIONAL AND EPIGENETIC REGULATION AND MODULATION BY EXTRACELLULAR BINDING PROTEINS. DUE TO ITS ACTIONS IN PROMOTING MUSCLE ATROPHY AND CACHEXIA, MYOSTATIN HAS BEEN INVESTIGATED AS A PROMISING THERAPEUTIC TARGET TO COUNTERACT MUSCLE MASS LOSS IN EXPERIMENTAL MODELS AND PATIENTS AFFECTED BY DIFFERENT MUSCLE-WASTING CONDITIONS. MOREOVER, GROWING EVIDENCE INDICATES THAT MYOSTATIN, BEYOND TO REGULATE SKELETAL MUSCLE GROWTH, MAY HAVE A ROLE IN MANY PHYSIOLOGIC AND PATHOLOGIC PROCESSES, SUCH AS OBESITY, INSULIN RESISTANCE, CARDIOVASCULAR AND CHRONIC KIDNEY DISEASE. IN THIS CHAPTER, WE REVIEW MYOSTATIN BIOLOGY, INCLUDING INTRACELLULAR AND EXTRACELLULAR REGULATORY PATHWAYS, AND THE ROLE OF MYOSTATIN IN MODULATING PHYSIOLOGIC PROCESSES, SUCH AS MUSCLE GROWTH AND AGING. MOREOVER, WE DISCUSS THE MOST RELEVANT EXPERIMENTAL AND CLINICAL EVIDENCE SUPPORTING THE EXTRA-MUSCLE EFFECTS OF MYOSTATIN. FINALLY, WE CONSIDER THE MAIN STRATEGIES DEVELOPED AND TESTED TO INHIBIT MYOSTATIN IN CLINICAL TRIALS AND DISCUSS THE LIMITS AND FUTURE PERSPECTIVES OF THE RESEARCH ON MYOSTATIN.	2022	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
17  5995  28 TGFBETA-INDUCED FIBROBLAST ACTIVATION REQUIRES PERSISTENT AND TARGETED HDAC-MEDIATED GENE REPRESSION. TISSUE FIBROSIS IS A CHRONIC DISEASE DRIVEN BY PERSISTENT FIBROBLAST ACTIVATION THAT HAS RECENTLY BEEN LINKED TO EPIGENETIC MODIFICATIONS. HERE, WE SCREENED A SMALL LIBRARY OF EPIGENETIC SMALL-MOLECULE MODULATORS TO IDENTIFY COMPOUNDS CAPABLE OF INHIBITING OR REVERSING TGFBETA-MEDIATED FIBROBLAST ACTIVATION. WE IDENTIFIED PRACINOSTAT, AN HDAC INHIBITOR, AS A POTENT ATTENUATOR OF LUNG FIBROBLAST ACTIVATION AND CONFIRMED ITS EFFICACY IN PATIENT-DERIVED FIBROBLASTS ISOLATED FROM FIBROTIC LUNG TISSUE. MECHANISTICALLY, WE FOUND THAT HDAC-DEPENDENT TRANSCRIPTIONAL REPRESSION WAS AN EARLY AND ESSENTIAL EVENT IN TGFBETA-MEDIATED FIBROBLAST ACTIVATION. TREATMENT OF LUNG FIBROBLASTS WITH PRACINOSTAT BROADLY ATTENUATED TGFBETA-MEDIATED EPIGENETIC REPRESSION AND PROMOTED FIBROBLAST QUIESCENCE. WE CONFIRMED A SPECIFIC ROLE FOR HDAC-DEPENDENT HISTONE DEACETYLATION IN THE PROMOTER REGION OF THE ANTI-FIBROTIC GENE PPARGC1A (PGC1ALPHA) IN RESPONSE TO TGFBETA STIMULATION. FINALLY, WE IDENTIFIED HDAC7 AS A KEY FACTOR WHOSE SIRNA-MEDIATED KNOCKDOWN ATTENUATES FIBROBLAST ACTIVATION WITHOUT ALTERING GLOBAL HISTONE ACETYLATION. TOGETHER, THESE RESULTS PROVIDE NOVEL MECHANISTIC INSIGHT INTO THE ESSENTIAL ROLE HDACS PLAY IN TGFBETA-MEDIATED FIBROBLAST ACTIVATION VIA TARGETED GENE REPRESSION.	2019	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
18  5993  23 TGFBETA PROMOTES FIBROSIS BY MYST1-DEPENDENT EPIGENETIC REGULATION OF AUTOPHAGY. ACTIVATION OF FIBROBLASTS IS ESSENTIAL FOR PHYSIOLOGICAL TISSUE REPAIR. UNCONTROLLED ACTIVATION OF FIBROBLASTS, HOWEVER, MAY LEAD TO TISSUE FIBROSIS WITH ORGAN DYSFUNCTION. ALTHOUGH SEVERAL PATHWAYS CAPABLE OF PROMOTING FIBROBLAST ACTIVATION AND TISSUE REPAIR HAVE BEEN IDENTIFIED, THEIR INTERPLAY IN THE CONTEXT OF CHRONIC FIBROTIC DISEASES REMAINS INCOMPLETELY UNDERSTOOD. HERE, WE PROVIDE EVIDENCE THAT TRANSFORMING GROWTH FACTOR-BETA (TGFBETA) ACTIVATES AUTOPHAGY BY AN EPIGENETIC MECHANISM TO AMPLIFY ITS PROFIBROTIC EFFECTS. TGFBETA INDUCES AUTOPHAGY IN FIBROTIC DISEASES BY SMAD3-DEPENDENT DOWNREGULATION OF THE H4K16 HISTONE ACETYLTRANSFERASE MYST1, WHICH REGULATES THE EXPRESSION OF CORE COMPONENTS OF THE AUTOPHAGY MACHINERY SUCH AS ATG7 AND BECLIN1. ACTIVATION OF AUTOPHAGY IN FIBROBLASTS PROMOTES COLLAGEN RELEASE AND IS BOTH, SUFFICIENT AND REQUIRED, TO INDUCE TISSUE FIBROSIS. FORCED EXPRESSION OF MYST1 ABROGATES THE STIMULATORY EFFECTS OF TGFBETA ON AUTOPHAGY AND RE-ESTABLISHES THE EPIGENETIC CONTROL OF AUTOPHAGY IN FIBROTIC CONDITIONS. INTERFERENCE WITH THE ABERRANT ACTIVATION OF AUTOPHAGY INHIBITS TGFBETA-INDUCED FIBROBLAST ACTIVATION AND AMELIORATES EXPERIMENTAL DERMAL AND PULMONARY FIBROSIS. THESE FINDINGS LINK UNCONTROLLED TGFBETA SIGNALING TO ABERRANT AUTOPHAGY AND DEREGULATED EPIGENETICS IN FIBROTIC DISEASES AND MAY CONTRIBUTE TO THE DEVELOPMENT OF THERAPEUTIC INTERVENTIONS IN FIBROTIC DISEASES.	2021	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
19   545  15 ATTENUATED EPIGENETIC SUPPRESSION OF MUSCLE STEM CELL NECROPTOSIS IS REQUIRED FOR EFFICIENT REGENERATION OF DYSTROPHIC MUSCLES. SOMATIC STEM CELLS EXPAND MASSIVELY DURING TISSUE REGENERATION, WHICH MIGHT REQUIRE CONTROL OF CELL FITNESS, ALLOWING ELIMINATION OF NON-COMPETITIVE, POTENTIALLY HARMFUL CELLS. HOW OR IF SUCH CELLS ARE REMOVED TO RESTORE ORGAN FUNCTION IS NOT FULLY UNDERSTOOD. HERE, WE SHOW THAT A SUBSTANTIAL FRACTION OF MUSCLE STEM CELLS (MUSCS) UNDERGO NECROPTOSIS BECAUSE OF EPIGENETIC REWIRING DURING CHRONIC SKELETAL MUSCLE REGENERATION, WHICH IS REQUIRED FOR EFFICIENT REGENERATION OF DYSTROPHIC MUSCLES. INHIBITION OF NECROPTOSIS STRONGLY ENHANCES SUPPRESSION OF MUSC EXPANSION IN A NON-CELL-AUTONOMOUS MANNER. PREVENTION OF NECROPTOSIS IN MUSCS OF HEALTHY MUSCLES IS MEDIATED BY THE CHROMATIN REMODELER CHD4, WHICH DIRECTLY REPRESSES THE NECROPTOTIC EFFECTOR RIPK3, WHILE CHD4-DEPENDENT RIPK3 REPRESSION IS DRAMATICALLY ATTENUATED IN DYSTROPHIC MUSCLES. LOSS OF RIPK3 REPRESSION BY INACTIVATION OF CHD4 CAUSES MASSIVE NECROPTOSIS OF MUSCS, ABOLISHING REGENERATION. OUR STUDY DEMONSTRATES HOW PROGRAMMED CELL DEATH IN MUSCS IS TIGHTLY CONTROLLED TO ACHIEVE OPTIMAL TISSUE REGENERATION.	2020	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
20  2170  69 EPIGENETIC MECHANISMS IN RESPIRATORY MUSCLE DYSFUNCTION OF PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE. EPIGENETIC EVENTS ARE DIFFERENTIALLY EXPRESSED IN THE LUNGS AND AIRWAYS OF PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). MOREOVER, EPIGENETIC MECHANISMS ARE INVOLVED IN THE SKELETAL (PERIPHERAL) MUSCLE DYSFUNCTION OF COPD PATIENTS. WHETHER EPIGENETIC EVENTS MAY ALSO REGULATE RESPIRATORY MUSCLE DYSFUNCTION IN COPD REMAINS UNKNOWN. WE HYPOTHESIZED THAT EPIGENETIC MECHANISMS WOULD BE DIFFERENTIALLY EXPRESSED IN THE MAIN INSPIRATORY MUSCLE (DIAPHRAGM) OF PATIENTS WITH COPD OF A WIDE RANGE OF DISEASE SEVERITY COMPARED TO HEALTHY CONTROLS. IN DIAPHRAGM MUSCLE SPECIMENS (THORACOTOMY DUE TO LUNG LOCALIZED NEOPLASMS) OF SEDENTARY PATIENTS WITH MILD-TO-MODERATE AND SEVERE COPD, WITH PRESERVED BODY COMPOSITION, AND SEDENTARY HEALTHY CONTROLS, EXPRESSION OF MUSCLE-ENRICHED MICRORNAS, HISTONE ACETYLTRANSFERASES (HATS) AND DEACETYLASES (HDACS), TOTAL DNA METHYLATION AND PROTEIN ACETYLATION, SMALL UBIQUITIN-RELATED MODIFIER (SUMO) LIGASES, MUSCLE-SPECIFIC TRANSCRIPTION FACTORS, AND MUSCLE STRUCTURE WERE EXPLORED. ALL SUBJECTS WERE ALSO CLINICALLY EVALUATED: LUNG AND MUSCLE FUNCTIONS AND EXERCISE CAPACITY. COMPARED TO HEALTHY CONTROLS, PATIENTS EXHIBITED MODERATE AIRFLOW LIMITATION AND DIFFUSION CAPACITY, AND REDUCED EXERCISE TOLERANCE AND TRANSDIAPHRAGMATIC STRENGTH. MOREOVER, IN THE DIAPHRAGM OF THE COPD PATIENTS, MUSCLE-SPECIFIC MICRORNA EXPRESSION WAS DOWNREGULATED, WHILE HDAC4 AND MYOCYTE ENHANCER FACTOR (MEF)2C PROTEIN LEVELS WERE HIGHER, AND DNA METHYLATION LEVELS, MUSCLE FIBER TYPES AND SIZES DID NOT DIFFER BETWEEN PATIENTS AND CONTROLS. IN THE MAIN RESPIRATORY MUSCLE OF COPD PATIENTS WITH A WIDE RANGE OF DISEASE SEVERITY AND NORMAL BODY COMPOSITION, MUSCLE-SPECIFIC MICRORNAS WERE DOWNREGULATED, WHILE HDAC4 AND MEF2C LEVELS WERE UPREGULATED. IT IS LIKELY THAT THESE EPIGENETIC EVENTS ACT AS BIOLOGICAL ADAPTIVE MECHANISMS TO BETTER OVERCOME THE CONTINUOUS INSPIRATORY LOADS OF THE RESPIRATORY SYSTEM IN COPD. THESE FINDINGS MAY OFFER NOVEL THERAPEUTIC STRATEGIES TO SPECIFICALLY TARGET RESPIRATORY MUSCLE DYSFUNCTION IN PATIENTS WITH COPD.	2014