1 5672 128 SHARED AND DIVERGENT EPIGENETIC MECHANISMS IN CACHEXIA AND SARCOPENIA. SIGNIFICANT LOSS OF MUSCLE MASS MAY OCCUR IN CACHEXIA AND SARCOPENIA, WHICH ARE MAJOR CAUSES OF MORTALITY AND DISABILITY. CACHEXIA REPRESENTS A COMPLEX MULTI-ORGAN SYNDROME ASSOCIATED WITH CANCER AND CHRONIC DISEASES. IT IS OFTEN CHARACTERIZED BY BODY WEIGHT LOSS, INFLAMMATION, AND MUSCLE AND ADIPOSE WASTING. PROGRESSIVE MUSCLE LOSS IS ALSO A HALLMARK OF HEALTHY AGING, WHICH IS EMERGING WORLDWIDE AS A MAIN DEMOGRAPHIC TREND. A GREAT CHALLENGE FOR THE HEALTH CARE SYSTEMS IS THE AGE-RELATED DECLINE IN FUNCTIONALITY WHICH THREATENS THE INDEPENDENCE AND QUALITY OF LIFE OF ELDERLY PEOPLE. THIS BIOLOGICAL DECLINE CAN ALSO BE ASSOCIATED WITH FUNCTIONAL MUSCLE LOSS, KNOWN AS SARCOPENIA. PREVIOUS STUDIES HAVE SHOWN THAT MICRORNAS (MIRNAS) PLAY PIVOTAL ROLES IN THE DEVELOPMENT AND PROGRESSION OF MUSCLE WASTING IN BOTH CACHEXIA AND SARCOPENIA. THESE SMALL NON-CODING RNAS, OFTEN CARRIED IN EXTRACELLULAR VESICLES, INHIBIT TRANSLATION BY TARGETING MESSENGER RNAS, THEREFORE REPRESENTING POTENT EPIGENETIC MODULATORS. THE MOLECULAR MECHANISMS BEHIND CACHEXIA AND SARCOPENIA, INCLUDING THE EXPRESSION OF SPECIFIC MIRNAS, SHARE COMMON AND DISTINCTIVE TRENDS. THE AIM OF THE PRESENT REVIEW IS TO COMPILE RECENT EVIDENCE ABOUT SHARED AND DIVERGENT EPIGENETIC MECHANISMS, PARTICULARLY FOCUSING ON MIRNAS, BETWEEN CACHEXIA AND SARCOPENIA TO UNDERSTAND A FACET IN THE UNDERLYING MUSCLE WASTING ASSOCIATED WITH THESE MORBIDITIES AND DISCLOSE POTENTIAL THERAPEUTIC INTERVENTIONS. 2022 2 5724 39 SKELETAL MUSCLE WASTING AND ITS RELATIONSHIP WITH OSTEOARTHRITIS: A MINI-REVIEW OF MECHANISMS AND CURRENT INTERVENTIONS. PURPOSE OF REVIEW: OSTEOARTHRITIS (OA) IS A SUBSET OF JOINT DISORDERS RESULTING IN DEGENERATION OF SYNOVIAL JOINTS. THIS LEADS TO PAIN, DISABILITY AND LOSS OF INDEPENDENCE. KNEE AND HIP OA ARE EXTREMELY PREVALENT, AND THEIR OCCURRENCE INCREASES WITH AGEING. SIMILARLY, LOSS OF MUSCLE MASS AND FUNCTION, SARCOPENIA, OCCURS DURING AGEING. RECENT FINDINGS: LITTLE IS KNOWN ABOUT THE IMPACT OF MUSCLE WASTING ON OA PROGRESSION; NEVERTHELESS, IT HAS BEEN SUGGESTED THAT MUSCLE WASTING DIRECTLY AFFECTS THE STABILITY OF THE JOINTS AND LOSS OF MOBILITY LEADS TO GRADUAL DEGENERATION OF ARTICULAR CARTILAGE. THE MOLECULAR MECHANISMS UNDERLYING MUSCLE WASTING IN OA ARE NOT WELL UNDERSTOOD; HOWEVER, THESE ARE PROBABLY RELATED TO CHANGES IN GENE EXPRESSION, AS WELL AS EPIGENETIC MODIFICATIONS. IT IS BECOMING CLEAR THAT SKELETAL MUSCLE WASTING PLAYS AN IMPORTANT ROLE IN OA DEVELOPMENT AND/OR PROGRESSION. HERE, WE DISCUSS MECHANISMS, CURRENT INTERVENTIONS, SUCH AS EXERCISE, AND POTENTIALLY NOVEL APPROACHES, SUCH AS MODULATION OF MICRORNAS, AIMING AT AMELIORATING OA SYMPTOMS THROUGH MAINTAINING MUSCLE MASS AND FUNCTION. 2019 3 4047 35 MAIN PATHOGENIC MECHANISMS AND RECENT ADVANCES IN COPD PERIPHERAL SKELETAL MUSCLE WASTING. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) IS A WORLDWIDE PREVALENT RESPIRATORY DISEASE MAINLY CAUSED BY TOBACCO SMOKE EXPOSURE. COPD IS NOW CONSIDERED AS A SYSTEMIC DISEASE WITH SEVERAL COMORBIDITIES. AMONG THEM, SKELETAL MUSCLE DYSFUNCTION AFFECTS AROUND 20% OF COPD PATIENTS AND IS ASSOCIATED WITH HIGHER MORBIDITY AND MORTALITY. ALTHOUGH THE HISTOLOGICAL ALTERATIONS ARE WELL CHARACTERIZED, INCLUDING MYOFIBER ATROPHY, A DECREASED PROPORTION OF SLOW-TWITCH MYOFIBERS, AND A DECREASED CAPILLARIZATION AND OXIDATIVE PHOSPHORYLATION CAPACITY, THE MOLECULAR BASIS FOR MUSCLE ATROPHY IS COMPLEX AND REMAINS PARTLY UNKNOWN. MAJOR DIFFICULTIES LIE IN PATIENT HETEROGENEITY, ACCESSING PATIENTS' SAMPLES, AND COMPLEX MULTIFACTORIAL PROCESS INCLUDING EXTRINSIC MECHANISMS, SUCH AS TOBACCO SMOKE OR DISUSE, AND INTRINSIC MECHANISMS, SUCH AS OXIDATIVE STRESS, HYPOXIA, OR SYSTEMIC INFLAMMATION. MUSCLE WASTING IS ALSO A HIGHLY DYNAMIC PROCESS WHOSE INVESTIGATION IS HAMPERED BY THE DIFFERENTIAL PROTEIN REGULATION ACCORDING TO THE STAGE OF ATROPHY. IN THIS REVIEW, WE REPORT AND DISCUSS RECENT DATA REGARDING THE MOLECULAR ALTERATIONS IN COPD LEADING TO IMPAIRED MUSCLE MASS, INCLUDING INFLAMMATION, HYPOXIA AND HYPERCAPNIA, MITOCHONDRIAL DYSFUNCTION, DIVERSE METABOLIC CHANGES SUCH AS OXIDATIVE AND NITROSATIVE STRESS AND GENETIC AND EPIGENETIC MODIFICATIONS, ALL LEADING TO AN IMPAIRED ANABOLIC/CATABOLIC BALANCE IN THE MYOCYTE. WE RECAPITULATE DATA CONCERNING SKELETAL MUSCLE DYSFUNCTION OBTAINED IN THE DIFFERENT RODENT MODELS OF COPD. FINALLY, WE PROPOSE SEVERAL PATHWAYS THAT SHOULD BE INVESTIGATED IN COPD SKELETAL MUSCLE DYSFUNCTION IN THE FUTURE. 2023 4 1642 36 DOES INFLAMMATION AFFECT OUTCOMES IN DIALYSIS PATIENTS? CHRONIC, LOW-GRADE INFLAMMATION IS A COMMON COMORBID CONDITION IN CHRONIC KIDNEY DISEASE (CKD), AND PARTICULARLY IN CHRONIC DIALYSIS PATIENTS. IN THIS REVIEW, WE CONSIDER THE QUESTION OF WHETHER INFLAMMATION AFFECTS OUTCOMES IN DIALYSIS PATIENTS. LEVELS OF PROINFLAMMATORY CYTOKINES, AS WELL AS C-REACTIVE PROTEIN, ARE ELEVATED IN CHRONIC DIALYSIS PATIENTS. MULTIPLE FACTORS LIKELY CONTRIBUTE TO CHRONIC INFLAMMATORY ACTIVATION IN KIDNEY DISEASE PATIENTS INCLUDING THE UREMIC MILIEU, LIFESTYLE AND EPIGENETIC INFLUENCES, INFECTIOUS AND THROMBOTIC EVENTS, THE DIALYSIS PROCESS, AND DYSBIOSIS. INCREASED INFLAMMATORY MARKERS IN BOTH CKD AND CHRONIC DIALYSIS PATIENTS ARE ASSOCIATED WITH ADVERSE CLINICAL OUTCOMES INCLUDING ALL-CAUSE MORTALITY, CARDIOVASCULAR EVENTS, KIDNEY DISEASE PROGRESSION, PROTEIN ENERGY WASTING AND DIMINISHED MOTOR FUNCTION, COGNITIVE IMPAIRMENT, AS WELL AS OTHER ADVERSE CONSEQUENCES INCLUDING CKD-MINERAL AND BONE DISORDER, ANEMIA, AND INSULIN RESISTANCE. STRATEGIES THAT HAVE BEEN SHOWN TO REDUCE CHRONIC SYSTEMIC INFLAMMATION IN CKD AND CHRONIC DIALYSIS PATIENTS INCLUDE BOTH PHARMACOLOGICAL AND NONPHARMACOLOGICAL INTERVENTIONS. HOWEVER, DESPITE EVIDENCE THAT SYSTEMIC INFLAMMATORY MARKERS CAN BE LOWERED IN KIDNEY DISEASE PATIENTS TREATED WITH VARIOUS STRATEGIES, EVIDENCE THAT THIS IMPROVES CLINICAL OUTCOMES IS LARGELY UNAVAILABLE AND REPRESENTS AN IMPORTANT FUTURE RESEARCH DIRECTION. OVERALL, THERE IS STRONG OBSERVATIONAL EVIDENCE THAT INFLAMMATION IS HIGH IN CHRONIC DIALYSIS PATIENTS AND THAT THIS IS INDEPENDENTLY ASSOCIATED WITH NUMEROUS ADVERSE CLINICAL OUTCOMES. TARGETING INFLAMMATION REPRESENTS A POTENTIALLY NOVEL AND ATTRACTIVE STRATEGY IF IT CAN INDEED IMPROVE ADVERSE OUTCOMES COMMON IN THIS POPULATION. 2018 5 6652 32 UPDATE ON INFLAMMATION IN CHRONIC KIDNEY DISEASE. BACKGROUND: DESPITE RECENT ADVANCES IN CHRONIC KIDNEY DISEASE (CKD) AND END-STAGE RENAL DISEASE (ESRD) MANAGEMENT, MORBIDITY AND MORTALITY IN THIS POPULATION REMAIN EXCEPTIONALLY HIGH. PERSISTENT, LOW-GRADE INFLAMMATION HAS BEEN RECOGNIZED AS AN IMPORTANT COMPONENT OF CKD, PLAYING A UNIQUE ROLE IN ITS PATHOPHYSIOLOGY AND BEING ACCOUNTABLE IN PART FOR CARDIOVASCULAR AND ALL-CAUSE MORTALITY, AS WELL AS CONTRIBUTING TO THE DEVELOPMENT OF PROTEIN-ENERGY WASTING. SUMMARY: THE VARIETY OF FACTORS CONTRIBUTE TO CHRONIC INFLAMMATORY STATUS IN CKD, INCLUDING INCREASED PRODUCTION AND DECREASED CLEARANCE OF PRO-INFLAMMATORY CYTOKINES, OXIDATIVE STRESS AND ACIDOSIS, CHRONIC AND RECURRENT INFECTIONS, INCLUDING THOSE RELATED TO DIALYSIS ACCESS, ALTERED METABOLISM OF ADIPOSE TISSUE, AND INTESTINAL DYSBIOSIS. INFLAMMATION DIRECTLY CORRELATES WITH THE GLOMERULAR FILTRATION RATE (GFR) IN CKD AND CULMINATES IN DIALYSIS PATIENTS, WHERE EXTRACORPOREAL FACTORS, SUCH AS IMPURITIES IN DIALYSIS WATER, MICROBIOLOGICAL QUALITY OF THE DIALYSATE, AND BIOINCOMPATIBLE FACTORS IN THE DIALYSIS CIRCUIT PLAY AN ADDITIONAL ROLE. GENETIC AND EPIGENETIC INFLUENCES CONTRIBUTING TO INFLAMMATORY ACTIVATION IN CKD ARE CURRENTLY BEING INTENSIVELY INVESTIGATED. A NUMBER OF INTERVENTIONS HAVE BEEN PROPOSED TO TARGET INFLAMMATION IN CKD, INCLUDING LIFESTYLE MODIFICATIONS, PHARMACOLOGICAL AGENTS, AND OPTIMIZATION OF DIALYSIS. IMPORTANTLY, SOME OF THESE THERAPIES HAVE BEEN RECENTLY TESTED IN RANDOMIZED CONTROLLED TRIALS. KEY MESSAGES: CHRONIC INFLAMMATION SHOULD BE REGARDED AS A COMMON COMORBID CONDITION IN CKD AND ESPECIALLY IN DIALYSIS PATIENTS. A NUMBER OF INTERVENTIONS HAVE BEEN PROVEN TO BE SAFE AND EFFECTIVE IN WELL-DESIGNED CLINICAL STUDIES. THIS INCLUDES SUCH INEXPENSIVE APPROACHES AS MODIFICATION OF PHYSICAL ACTIVITY AND DIETARY SUPPLEMENTATION. FURTHER INVESTIGATIONS ARE NEEDED TO EVALUATE THE EFFECTS OF THESE INTERVENTIONS ON HARD OUTCOMES, AS WELL AS TO BETTER UNDERSTAND THE ROLE OF INFLAMMATION IN SELECTED CKD POPULATIONS (E.G., IN CHILDREN). 2015 6 4928 35 PARP-1 AND PARP-2 ACTIVITY IN CANCER-INDUCED CACHEXIA: POTENTIAL THERAPEUTIC IMPLICATIONS. SKELETAL MUSCLE DYSFUNCTION AND MASS LOSS IS A CHARACTERISTIC FEATURE IN PATIENTS WITH CHRONIC DISEASES INCLUDING CANCER AND ACUTE CONDITIONS SUCH AS CRITICAL ILLNESS. MAINTENANCE OF AN ADEQUATE MUSCLE MASS IS CRUCIAL FOR THE PATIENTS' PROGNOSIS IRRESPECTIVE OF THE UNDERLYING CONDITION. MOREOVER, AGING-RELATED SARCOPENIA MAY FURTHER AGGRAVATE THE MUSCLE WASTING PROCESS ASSOCIATED WITH CHRONIC DISEASES AND CANCER. POLY(ADENOSINE DIPHOSPHATE-RIBOSE) POLYMERASE (PARP) ACTIVATION HAS BEEN DEMONSTRATED TO CONTRIBUTE TO THE PATHOPHYSIOLOGY OF MUSCLE MASS LOSS AND DYSFUNCTION IN ANIMAL MODELS OF CANCER-INDUCED CACHEXIA. GENETIC INHIBITION OF PARP ACTIVITY ATTENUATED THE DELETERIOUS EFFECTS SEEN ON DEPLETED MUSCLES IN MOUSE MODELS OF ONCOLOGIC CACHEXIA. IN THE PRESENT MINIREVIEW THE MECHANISMS WHEREBY PARP ACTIVITY INHIBITION MAY IMPROVE MUSCLE MASS AND PERFORMANCE IN MODELS OF CANCER-INDUCED CACHEXIA ARE DISCUSSED. SPECIFICALLY, THE BENEFICIAL EFFECTS OF INHIBITION OF PARP ACTIVITY ON ATTENUATION OF INCREASED OXIDATIVE STRESS, PROTEIN CATABOLISM, POOR MUSCLE ANABOLISM AND MITOCHONDRIAL CONTENT AND EPIGENETIC MODULATION OF MUSCLE PHENOTYPE ARE REVIEWED IN THIS ARTICLE. FINALLY, THE POTENTIAL THERAPEUTIC STRATEGIES OF PHARMACOLOGICAL PARP ACTIVITY INHIBITION FOR THE TREATMENT OF CANCER-INDUCED CACHEXIA ARE ALSO BEING DESCRIBED IN THIS REVIEW. 2018 7 1883 32 END-STAGE RENAL DISEASE, INFLAMMATION AND CARDIOVASCULAR OUTCOMES. DESPITE MARKED IMPROVEMENTS IN RENAL REPLACEMENT THERAPY DURING THE LAST 30 YEARS, THE AGE-ADJUSTED MORTALITY RATE IN END-STAGE RENAL DISEASE (ESRD) PATIENTS IS STILL UNACCEPTABLY HIGH AND COMPARABLE TO THAT OF MANY MALIGNANCIES. CARDIOVASCULAR DISEASE (CVD) REMAINS THE MAJOR CAUSE OF MORBIDITY AND MORTALITY IN ESRD PATIENTS. HOWEVER, TRADITIONAL RISK FACTORS CAN ONLY PARTIALLY EXPLAIN THE HIGH PREMATURE CARDIOVASCULAR BURDEN IN THIS POPULATION. NONTRADITIONAL RISK FACTORS, INCLUDING PERSISTENT LOW-GRADE INFLAMMATION, ARE CRITICAL IN THE PATHOGENESIS OF ATHEROSCLEROSIS, VASCULAR CALCIFICATION, AND OTHER CAUSES OF CVD AND MAY ALSO CONTRIBUTE TO PROTEIN-ENERGY WASTING AND OTHER COMPLICATIONS IN CHRONIC KIDNEY DISEASE (CKD) PATIENTS. INFLAMMATORY BIOMARKERS, SUCH AS HIGH SENSITIVITY C-REACTIVE PROTEIN AND INTERLEUKIN-6, INDEPENDENTLY PREDICT MORTALITY IN THESE PATIENTS. THE CAUSES OF INFLAMMATION IN CKD ARE MULTIFACTORIAL AND INCLUDE IMBALANCE BETWEEN INCREASED PRODUCTION (DUE TO MULTIPLE SOURCES OF INFLAMMATORY STIMULI SUCH AS OXIDATIVE STRESS, ACIDOSIS, VOLUME OVERLOAD, CO-MORBIDITIES, ESPECIALLY INFECTIONS, GENETIC AND EPIGENETIC INFLUENCES, AND THE DIALYSIS PROCEDURE) AND INADEQUATE REMOVAL (DUE TO DECREASED GLOMERULAR FILTRATION RATE OR IN ESRD PATIENTS, INADEQUATE DIALYTIC CLEARANCE) OF PRO-INFLAMMATORY CYTOKINES. THOUGH THERE ARE CURRENTLY NO ESTABLISHED GUIDELINES FOR THE TREATMENT OF LOW-GRADE INFLAMMATION IN ESRD PATIENTS, SEVERAL STRATEGIES HAVE BEEN PROPOSED, SUCH AS LIFESTYLE MODIFICATIONS, PHARMACOLOGICAL TREATMENT, AND OPTIMIZATION OF DIALYSIS. FURTHER STUDIES ON PATHWAYS INVOLVED IN PATHOGENIC PROCESSES OF INFLAMMATION IN ESRD, AND LONG-TERM EFFECTS OF ANTI-INFLAMMATORY INTERVENTIONS TARGETING PRODUCTION OR REMOVAL OF CYTOKINES OR BOTH ON PREMATURE CVD AND CLINICAL OUTCOMES IN THIS PATIENT GROUP ARE WARRANTED. 2017 8 4543 36 MUSCLE DYSFUNCTION IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE: UPDATE ON CAUSES AND BIOLOGICAL FINDINGS. RESPIRATORY AND/OR LIMB MUSCLE DYSFUNCTION, WHICH ARE FREQUENTLY OBSERVED IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) PATIENTS, CONTRIBUTE TO THEIR DISEASE PROGNOSIS IRRESPECTIVE OF THE LUNG FUNCTION. MUSCLE DYSFUNCTION IS CAUSED BY THE INTERACTION OF LOCAL AND SYSTEMIC FACTORS. THE KEY DELETERIOUS ETIOLOGIC FACTORS ARE PULMONARY HYPERINFLATION FOR THE RESPIRATORY MUSCLES AND DECONDITIONING SECONDARY TO REDUCED PHYSICAL ACTIVITY FOR LIMB MUSCLES. NONETHELESS, CIGARETTE SMOKE, SYSTEMIC INFLAMMATION, NUTRITIONAL ABNORMALITIES, EXERCISE, EXACERBATIONS, ANABOLIC INSUFFICIENCY, DRUGS AND COMORBIDITIES ALSO SEEM TO PLAY A RELEVANT ROLE. ALL THESE FACTORS MODIFY THE PHENOTYPE OF THE MUSCLES, THROUGH THE INDUCTION OF SEVERAL BIOLOGICAL PHENOMENA IN PATIENTS WITH COPD. WHILE RESPIRATORY MUSCLES IMPROVE THEIR AEROBIC PHENOTYPE (PERCENTAGE OF OXIDATIVE FIBERS, CAPILLARIZATION, MITOCHONDRIAL DENSITY, ENZYME ACTIVITY IN THE AEROBIC PATHWAYS, ETC.), LIMB MUSCLES EXHIBIT THE OPPOSITE PHENOTYPE. IN ADDITION, BOTH MUSCLE GROUPS SHOW OXIDATIVE STRESS, SIGNS OF DAMAGE AND EPIGENETIC CHANGES. HOWEVER, FIBER ATROPHY, INCREASED NUMBER OF INFLAMMATORY CELLS, ALTERED REGENERATIVE CAPACITY; SIGNS OF APOPTOSIS AND AUTOPHAGY, AND AN IMBALANCE BETWEEN PROTEIN SYNTHESIS AND BREAKDOWN ARE RATHER CHARACTERISTIC FEATURES OF THE LIMB MUSCLES, MOSTLY IN PATIENTS WITH REDUCED BODY WEIGHT. DESPITE THAT SIGNIFICANT PROGRESS HAS BEEN ACHIEVED IN THE LAST DECADES, FULL ELUCIDATION OF THE SPECIFIC ROLES OF THE TARGET BIOLOGICAL MECHANISMS INVOLVED IN COPD MUSCLE DYSFUNCTION IS STILL REQUIRED. SUCH AN ACHIEVEMENT WILL BE CRUCIAL TO ADEQUATELY TACKLE WITH THIS RELEVANT CLINICAL PROBLEM OF COPD PATIENTS IN THE NEAR-FUTURE. 2015 9 6169 31 THE GUT MICROBIOTA AND HEALTHY AGING: A MINI-REVIEW. THE GUT MICROBIOTA SHOWS A WIDE INTER-INDIVIDUAL VARIATION, BUT ITS WITHIN-INDIVIDUAL VARIATION IS RELATIVELY STABLE OVER TIME. A FUNCTIONAL CORE MICROBIOME, PROVIDED BY ABUNDANT BACTERIAL TAXA, SEEMS TO BE COMMON TO VARIOUS HUMAN HOSTS REGARDLESS OF THEIR GENDER, GEOGRAPHIC LOCATION, AND AGE. WITH ADVANCING CHRONOLOGICAL AGE, THE GUT MICROBIOTA BECOMES MORE DIVERSE AND VARIABLE. HOWEVER, WHEN MEASURES OF BIOLOGICAL AGE ARE USED WITH ADJUSTMENT FOR CHRONOLOGICAL AGE, OVERALL RICHNESS DECREASES, WHILE A CERTAIN GROUP OF BACTERIA ASSOCIATED WITH FRAILTY INCREASES. THIS HIGHLIGHTS THE IMPORTANCE OF CONSIDERING BIOLOGICAL OR FUNCTIONAL MEASURES OF AGING. STUDIES USING MODEL ORGANISMS INDICATE THAT AGE-RELATED GUT DYSBIOSIS MAY CONTRIBUTE TO UNHEALTHY AGING AND REDUCED LONGEVITY. THE GUT MICROBIOME DEPENDS ON THE HOST NUTRIENT SIGNALING PATHWAYS FOR ITS BENEFICIAL EFFECTS ON HOST HEALTH AND LIFESPAN, AND GUT DYSBIOSIS DISRUPTING THE INTERDEPENDENCE MAY DIMINISH THE BENEFICIAL EFFECTS OR EVEN HAVE REVERSE EFFECTS. GUT DYSBIOSIS CAN TRIGGER THE INNATE IMMUNE RESPONSE AND CHRONIC LOW-GRADE INFLAMMATION, LEADING TO MANY AGE-RELATED DEGENERATIVE PATHOLOGIES AND UNHEALTHY AGING. THE GUT MICROBIOTA COMMUNICATES WITH THE HOST THROUGH VARIOUS BIOMOLECULES, NUTRIENT SIGNALING-INDEPENDENT PATHWAYS, AND EPIGENETIC MECHANISMS. DISTURBANCE OF THESE COMMUNICATIONS BY AGE-RELATED GUT DYSBIOSIS CAN AFFECT THE HOST HEALTH AND LIFESPAN. THIS MAY EXPLAIN THE IMPACT OF THE GUT MICROBIOME ON HEALTH AND AGING. 2018 10 4410 34 MOLECULAR AND BIOLOGICAL PATHWAYS OF SKELETAL MUSCLE DYSFUNCTION IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) WILL BE A MAJOR LEADING CAUSE OF DEATH WORLDWIDE IN THE NEAR FUTURE. WEAKNESS AND ATROPHY OF THE QUADRICEPS ARE ASSOCIATED WITH A SIGNIFICANTLY POORER PROGNOSIS AND INCREASED MORTALITY IN COPD. DESPITE THAT SKELETAL MUSCLE DYSFUNCTION MAY AFFECT BOTH RESPIRATORY AND LIMB MUSCLE GROUPS IN COPD, THE LATTER ARE FREQUENTLY MORE SEVERELY AFFECTED. THEREFORE, MUSCLE DYSFUNCTION IN COPD IS A COMMON SYSTEMIC MANIFESTATION THAT SHOULD BE EVALUATED ON ROUTINE BASIS IN CLINICAL SETTINGS. IN THE PRESENT REVIEW, SEVERAL ASPECTS OF COPD MUSCLE DYSFUNCTION ARE BEING REVIEWED, WITH SPECIAL EMPHASIS ON THE UNDERLYING BIOLOGICAL MECHANISMS. FIGURES ON THE PREVALENCE OF COPD MUSCLE DYSFUNCTION AND THE MOST RELEVANT ETIOLOGIC CONTRIBUTORS ARE ALSO PROVIDED. DESPITE THAT ONGOING RESEARCH WILL SHED LIGHT INTO THE CONTRIBUTION OF ADDITIONAL MECHANISMS TO COPD MUSCLE DYSFUNCTION, CURRENT KNOWLEDGE POINTS TOWARD THE INVOLVEMENT OF A WIDE SPECTRUM OF CELLULAR AND MOLECULAR EVENTS THAT ARE DIFFERENTIALLY EXPRESSED IN RESPIRATORY AND LIMB MUSCLES. SUCH MECHANISMS ARE THOROUGHLY DESCRIBED IN THE ARTICLE. THE CONTRIBUTION OF EPIGENETIC EVENTS ON COPD MUSCLE DYSFUNCTION IS ALSO REVIEWED. WE CONCLUDE THAT IN VIEW OF THE LATEST DISCOVERIES, FROM NOW, ON NEW AVENUES OF RESEARCH SHOULD BE DESIGNED TO SPECIFICALLY TARGET CELLULAR MECHANISMS AND PATHWAYS THAT IMPAIR MUSCLE MASS AND FUNCTION IN COPD USING PHARMACOLOGICAL STRATEGIES AND/OR EXERCISE TRAINING MODALITIES. 2016 11 2505 45 EPIGENETICS AND MUSCLE DYSFUNCTION IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) IS A COMMON, PREVENTABLE, AND TREATABLE DISEASE AND A MAJOR LEADING CAUSE OF MORBIDITY AND MORTALITY WORLDWIDE. IN COPD, COMORBIDITIES, ACUTE EXACERBATIONS, AND SYSTEMIC MANIFESTATIONS NEGATIVELY INFLUENCE DISEASE SEVERITY AND PROGRESSION REGARDLESS OF THE RESPIRATORY CONDITION. SKELETAL MUSCLE DYSFUNCTION, WHICH IS ONE OF THE COMMONEST SYSTEMIC MANIFESTATIONS IN PATIENTS WITH COPD, HAS A TREMENDOUS IMPACT ON THEIR EXERCISE CAPACITY AND QUALITY OF LIFE. SEVERAL PATHOPHYSIOLOGICAL AND MOLECULAR UNDERLYING MECHANISMS INCLUDING EPIGENETICS (THE PROCESS WHEREBY GENE EXPRESSION IS REGULATED BY HERITABLE MECHANISMS THAT DO NOT AFFECT DNA SEQUENCE) HAVE BEEN SHOWN TO PARTICIPATE IN THE ETIOLOGY OF COPD MUSCLE DYSFUNCTION. THE EPIGENETIC MODIFICATIONS IDENTIFIED SO FAR IN CELLS INCLUDE DNA METHYLATION, HISTONE ACETYLATION AND METHYLATION, AND NONCODING RNAS SUCH AS MICRORNAS. HEREIN, WE FIRST REVIEW THE ROLE OF EPIGENETIC MECHANISMS IN MUSCLE DEVELOPMENT AND ADAPTATION TO ENVIRONMENTAL FACTORS IN SEVERAL MODELS. MOREOVER, THE EPIGENETIC EVENTS REPORTED SO FAR TO BE POTENTIALLY INVOLVED IN MUSCLE DYSFUNCTION AND MASS LOSS OF PATIENTS WITH COPD ARE ALSO DISCUSSED. FURTHERMORE, THE DIFFERENT EXPRESSION PROFILE OF SEVERAL MUSCLE-ENRICHED MICRORNAS IN THE DIAPHRAGM AND VASTUS LATERALIS MUSCLES OF PATIENTS WITH COPD ARE ALSO REVIEWED FROM RESULTS RECENTLY OBTAINED IN OUR GROUP. THE ROLE OF PROTEIN HYPERACETYLATION IN ENHANCED MUSCLE PROTEIN CATABOLISM OF LIMB MUSCLES IS ALSO DISCUSSED. FUTURE RESEARCH SHOULD FOCUS ON THE FULL ELUCIDATION OF THE TRIGGERS OF EPIGENETIC MECHANISMS AND THEIR SPECIFIC DOWNSTREAM BIOLOGICAL PATHWAYS IN COPD MUSCLE DYSFUNCTION AND WASTING. 2015 12 4974 36 PATHOPHYSIOLOGICAL MECHANISMS LEADING TO MUSCLE LOSS IN CHRONIC KIDNEY DISEASE. LOSS OF MUSCLE PROTEINS IS A DELETERIOUS CONSEQUENCE OF CHRONIC KIDNEY DISEASE (CKD) THAT CAUSES A DECREASE IN MUSCLE STRENGTH AND FUNCTION, AND CAN LEAD TO A REDUCTION IN QUALITY OF LIFE AND INCREASED RISK OF MORBIDITY AND MORTALITY. THE EFFECTIVENESS OF CURRENT TREATMENT STRATEGIES IN PREVENTING OR REVERSING MUSCLE PROTEIN LOSSES IS LIMITED. THE LIMITATIONS LARGELY STEM FROM THE SYSTEMIC NATURE OF DISEASES SUCH AS CKD, WHICH STIMULATE SKELETAL MUSCLE PROTEIN DEGRADATION PATHWAYS WHILE SIMULTANEOUSLY ACTIVATING MECHANISMS THAT IMPAIR MUSCLE PROTEIN SYNTHESIS AND REPAIR. STIMULI THAT INITIATE MUSCLE PROTEIN LOSS INCLUDE METABOLIC ACIDOSIS, INSULIN AND IGF1 RESISTANCE, CHANGES IN HORMONES, CYTOKINES, INFLAMMATORY PROCESSES AND DECREASED APPETITE. A GROWING BODY OF EVIDENCE SUGGESTS THAT SIGNALLING MOLECULES SECRETED FROM MUSCLE CAN ENTER THE CIRCULATION AND SUBSEQUENTLY INTERACT WITH RECIPIENT ORGANS, INCLUDING THE KIDNEYS, WHILE CONVERSELY, PATHOLOGICAL EVENTS IN THE KIDNEY CAN ADVERSELY INFLUENCE PROTEIN METABOLISM IN SKELETAL MUSCLE, DEMONSTRATING THE EXISTENCE OF CROSSTALK BETWEEN KIDNEY AND MUSCLE. TOGETHER, THESE SIGNALS, WHETHER DIRECT OR INDIRECT, INDUCE CHANGES IN THE LEVELS OF REGULATORY AND EFFECTOR PROTEINS VIA ALTERATIONS IN MRNAS, MICRORNAS AND CHROMATIN EPIGENETIC RESPONSES. ADVANCES IN OUR UNDERSTANDING OF THE SIGNALS AND PROCESSES THAT MEDIATE MUSCLE LOSS IN CKD AND OTHER MUSCLE WASTING CONDITIONS WILL SUPPORT THE FUTURE DEVELOPMENT OF THERAPEUTIC STRATEGIES TO REDUCE MUSCLE LOSS. 2022 13 792 43 CELLULAR MECHANISMS PROMOTING CACHEXIA AND HOW THEY ARE OPPOSED BY SIRTUINS (1). MANY CHRONIC DISEASES ARE ASSOCIATED WITH UNINTENTIONAL LOSS OF BODY WEIGHT, WHICH IS TERMED "CACHEXIA". CACHEXIA IS A COMPLEX MULTIFACTORIAL SYNDROME ASSOCIATED WITH THE UNDERLYING PRIMARY DISEASE, AND CHARACTERIZED BY LOSS OF SKELETAL MUSCLE WITH OR WITHOUT LOSS OF FAT TISSUE. PATIENTS WITH CACHEXIA FACE DIRE SYMPTOMS LIKE DYSPNEA, FATIGUE, EDEMA, EXERCISE INTOLERANCE, AND LOW RESPONSIVENESS TO MEDICAL THERAPY, WHICH WORSEN QUALITY OF LIFE. BECAUSE CACHEXIA IS NOT A STAND-ALONE DISORDER, TREATING PRIMARY DISEASE - SUCH AS CANCER - TAKES PRECEDENCE FOR THE PHYSICIAN, AND IT REMAINS MOSTLY A NEGLECTED ILLNESS. EXISTING CLINICAL TRIALS HAVE DEMONSTRATED LIMITED SUCCESS MOSTLY BECAUSE OF THEIR MONOTHERAPEUTIC APPROACH AND LATE DETECTION OF THE SYNDROME. TO CONQUER CACHEXIA, IT IS ESSENTIAL TO IDENTIFY AS MANY MOLECULAR TARGETS AS POSSIBLE USING THE LATEST TECHNOLOGIES WE HAVE AT OUR DISPOSAL. IN THIS REVIEW, WE HAVE DISCUSSED DIFFERENT ASPECTS OF CACHEXIA, WHICH INCLUDE VARIOUS DISEASE SETTINGS, ACTIVE MOLECULAR PATHWAYS, AND RECENT NOVEL ADVANCES MADE IN THIS FIELD TO UNDERSTAND CONSEQUENCES OF THIS ILLNESS. WE ALSO DISCUSS ROLES OF THE SIRTUINS, THE NAD(+)-DEPENDENT LYSINE DEACETYLASES, MICRORNAS, CERTAIN DIETARY OPTIONS, AND EPIGENETIC DRUGS AS POTENTIAL APPROACHES, WHICH CAN BE USED TO TACKLE CACHEXIA AS EARLY AS POSSIBLE IN ITS COURSE. 2019 14 361 43 AMBIENT AIR POLLUTION AND THROMBOSIS. AIR POLLUTION IS A GROWING PUBLIC HEALTH CONCERN OF GLOBAL SIGNIFICANCE. ACUTE AND CHRONIC EXPOSURE IS KNOWN TO IMPAIR CARDIOVASCULAR FUNCTION, EXACERBATE DISEASE AND INCREASE CARDIOVASCULAR MORTALITY. SEVERAL PLAUSIBLE BIOLOGICAL MECHANISMS HAVE BEEN PROPOSED FOR THESE ASSOCIATIONS, HOWEVER, AT PRESENT, THE PATHWAYS ARE INCOMPLETE. A SEMINAL REVIEW BY THE AMERICAN HEART ASSOCIATION (2010) CONCLUDED THAT THE THROMBOTIC EFFECTS OF PARTICULATE AIR POLLUTION LIKELY CONTRIBUTED TO THEIR EFFECTS ON CARDIOVASCULAR MORTALITY AND MORBIDITY. THE AIM OF THE CURRENT REVIEW IS TO APPRAISE THE NEWLY ACCUMULATED SCIENTIFIC EVIDENCE (2009-2016) ON CONTRIBUTION OF HAEMOSTASIS AND THROMBOSIS TOWARDS CARDIOVASCULAR DISEASE INDUCED BY EXPOSURE TO BOTH PARTICULATE AND GASEOUS POLLUTANTS.SEVENTY FOUR PUBLICATIONS WERE REVIEWED IN-DEPTH. THE WEIGHT OF EVIDENCE SUGGESTS THAT ACUTE EXPOSURE TO FINE PARTICULATE MATTER (PM(2.5)) INDUCES A SHIFT IN THE HAEMOSTATIC BALANCE TOWARDS A PRO-THROMBOTIC/PRO-COAGULATIVE STATE. INSUFFICIENT DATA WAS AVAILABLE TO ASCERTAIN IF A SIMILAR RELATIONSHIP EXISTS FOR GASEOUS POLLUTANTS, AND VERY FEW STUDIES HAVE ADDRESSED LONG-TERM EXPOSURE TO AMBIENT AIR POLLUTION. PLATELET ACTIVATION, OXIDATIVE STRESS, INTERPLAY BETWEEN INTERLEUKIN-6 AND TISSUE FACTOR, ALL APPEAR TO BE POTENTIALLY IMPORTANT MECHANISMS IN POLLUTION-MEDIATED THROMBOSIS, TOGETHER WITH AN EMERGING ROLE FOR CIRCULATING MICROVESICLES AND EPIGENETIC CHANGES.OVERALL, THE RECENT LITERATURE SUPPORTS, AND ARGUABLY STRENGTHENS, THE CONTENTION THAT AIR POLLUTION CONTRIBUTES TO CARDIOVASCULAR MORBIDITY BY PROMOTING HAEMOSTASIS. THE VOLUME AND DIVERSITY OF THE EVIDENCE HIGHLIGHTS THE COMPLEXITY OF THE PATHOPHYSIOLOGIC MECHANISMS BY WHICH AIR POLLUTION PROMOTES THROMBOSIS; MULTIPLE PATHWAYS ARE PLAUSIBLE AND IT IS MOST LIKELY THEY ACT IN CONCERT. FUTURE RESEARCH SHOULD ADDRESS THE ROLE GASEOUS POLLUTANTS PLAY IN THE CARDIOVASCULAR EFFECTS OF AIR POLLUTION MIXTURE AND DIRECT COMPARISON OF POTENTIALLY SUSCEPTIBLE GROUPS TO HEALTHY INDIVIDUALS. 2018 15 4786 40 NUTRITION AND HEALTH DURING MID-LIFE: SEARCHING FOR SOLUTIONS AND MEETING CHALLENGES FOR THE AGING POPULATION. INTERACTIONS BETWEEN GENETIC (GENOME) AND ENVIRONMENTAL FACTORS (EPIGENOME) OPERATE DURING A PERSON'S ENTIRE LIFESPAN. THE AGING PROCESS IS ASSOCIATED WITH SEVERAL CELLULAR AND ORGANIC FUNCTIONAL ALTERATIONS THAT, AT THE END, CAUSE MULTI-ORGANIC CELL FAILURE. EPIGENETIC MECHANISMS OF AGING ARE MODIFIABLE BY APPROPRIATE PREVENTIVE ACTIONS MEDIATED BY SIRTUINS, CALORIC INPUT, DIET COMPONENTS, ADIPOSE TISSUE-RELATED INFLAMMATORY REACTIONS, AND PHYSICAL ACTIVITY. THE MEDITERRANEAN LIFESTYLE HAS BEEN FOR MANY MILLENNIA A DAILY HABIT FOR PEOPLE IN WESTERN CIVILIZATIONS LIVING AROUND THE MEDITERRANEAN SEA WHO WORKED INTENSIVELY AND SURVIVED WITH VERY FEW SEASONAL FOODS. A HIGH ADHERENCE TO THE TRADITIONAL MEDITERRANEAN DIET IS ASSOCIATED WITH LOW MORTALITY (HIGHER LONGEVITY) AND REDUCED RISK OF DEVELOPING CHRONIC DISEASES, INCLUDING CANCER, THE METABOLIC SYNDROME, DEPRESSION AND CARDIOVASCULAR AND NEURODEGENERATIVE DISEASES. REPORTS INDICATE THAT SOME DIETARY COMPONENTS, SUCH AS OLIVE OIL, ANTIOXIDANTS, OMEGA-3 AND -6 POLYUNSATURATED ACIDS, POLYPHENOLS AND FLAVONOIDS, MEDIATE BENEFICIAL ANTI-AGING EFFECTS (ANTI-CHRONIC DISEASES AND INCREASED LONGEVITY). EQUALLY, PHYSICAL ACTIVITY DISPLAYS A POSITIVE EFFECT, PRODUCING CALORIC CONSUMPTION AND REGULATION OF ADIPOSE AND PANCREATIC FUNCTION. THE PREDICTIVE STRENGTH OF SOME FOOD PATTERNS MAY BE A WAY OF DEVELOPING RECOMMENDATIONS FOR FOOD AND HEALTH POLICIES. THIS PAPER WILL DISCUSS SEVERAL WAYS OF IMPROVING HEALTH DURING MID-LIFE, FOCUSING ON CERTAIN GROUPS OF FUNCTIONAL FOODS AND HEALTHY HABITS WHICH MAY REDUCE OR PREVENT AGE-RELATED CHRONIC DISEASES. 2013 16 1188 38 COPD: A MULTIFACTORIAL SYSTEMIC DISEASE. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) HAS TRADITIONALLY BEEN CONSIDERED A DISEASE OF THE LUNGS SECONDARY TO CIGARETTE SMOKING AND CHARACTERIZED BY AIRFLOW OBSTRUCTION DUE TO ABNORMALITIES OF BOTH AIRWAY (BRONCHITIS) AND LUNG PARENCHYMA (EMPHYSEMA). IT IS NOW WELL KNOWN THAT COPD IS ASSOCIATED WITH SIGNIFICANT SYSTEMIC ABNORMALITIES, SUCH AS RENAL AND HORMONAL ABNORMALITIES, MALNUTRITION, MUSCLE WASTING, OSTEOPOROSIS, AND ANEMIA. HOWEVER, IT IS STILL UNCLEAR WHETHER THEY REPRESENT CONSEQUENCES OF THE PULMONARY DISORDER, OR WHETHER COPD SHOULD BE CONSIDERED AS A SYSTEMIC DISEASE. THESE SYSTEMIC ABNORMALITIES HAVE BEEN ATTRIBUTED TO AN INCREASED LEVEL OF SYSTEMIC INFLAMMATION. CHRONIC INFLAMMATION, HOWEVER, MAY NOT BE THE ONLY CAUSE OF THE SYSTEMIC EFFECTS OF COPD. RECENT DATA FROM HUMANS AND ANIMAL MODELS SUPPORT THE VIEW THAT EMPHYSEMA MAY BE A VASCULAR DISEASE. OTHER STUDIES HAVE HIGHLIGHTED THE ROLE OF REPAIR FAILURE, BONE MARROW ABNORMALITY, GENETIC AND EPIGENETIC FACTORS, IMMUNOLOGICAL DISORDERS AND INFECTIONS AS POTENTIAL CAUSES OF COPD SYSTEMIC MANIFESTATIONS. BASED ON THIS NEW EVIDENCE, IT IS REASONABLE TO CONSIDER COPD, AND EMPHYSEMA IN PARTICULAR, AS 'A DISEASE WITH A SIGNIFICANT SYSTEMIC COMPONENT' IF NOT A 'SYSTEMIC DISEASE' PER SE. THE AIM OF THIS REVIEW IS TO GIVE AN OVERVIEW OF THE MOST RELEVANT AND INNOVATIVE HYPOTHESIS ABOUT THE EXTRAPULMONARY MANIFESTATIONS OF COPD. 2011 17 465 37 ARE TARGETED THERAPIES FOR DIABETIC CARDIOMYOPATHY ON THE HORIZON? DIABETES INCREASES THE RISK OF HEART FAILURE APPROXIMATELY 2.5-FOLD, INDEPENDENT OF CORONARY ARTERY DISEASE AND OTHER COMORBIDITIES. THIS PROCESS, TERMED DIABETIC CARDIOMYOPATHY, IS CHARACTERIZED BY INITIAL IMPAIRMENT OF LEFT VENTRICULAR (LV) RELAXATION FOLLOWED BY LV CONTRACTILE DYSFUNCTION. POST-MORTEM EXAMINATION REVEALS THAT HUMAN DIASTOLIC DYSFUNCTION IS CLOSELY ASSOCIATED WITH LV DAMAGE, INCLUDING CARDIOMYOCYTE HYPERTROPHY, APOPTOSIS AND FIBROSIS, WITH IMPAIRED CORONARY MICROVASCULAR PERFUSION. THE PATHOPHYSIOLOGICAL MECHANISMS UNDERPINNING THE CHARACTERISTIC FEATURES OF DIABETIC CARDIOMYOPATHY REMAIN POORLY UNDERSTOOD, ALTHOUGH MULTIPLE FACTORS INCLUDING ALTERED LIPID METABOLISM, MITOCHONDRIAL DYSFUNCTION, OXIDATIVE STRESS, ENDOPLASMIC RETICULUM (ER) STRESS, INFLAMMATION, AS WELL AS EPIGENETIC CHANGES, ARE IMPLICATED. DESPITE A RECENT RISE IN RESEARCH INTERROGATING THESE MECHANISMS AND AN INCREASED UNDERSTANDING OF THE CLINICAL IMPORTANCE OF DIABETIC CARDIOMYOPATHY, THERE REMAINS A LACK OF SPECIFIC TREATMENT STRATEGIES. HOW THE CHRONIC METABOLIC DISTURBANCES OBSERVED IN DIABETES LEAD TO STRUCTURAL AND FUNCTIONAL CHANGES REMAINS A PERTINENT QUESTION, AND IT IS HOPED THAT RECENT ADVANCES, PARTICULARLY IN THE AREA OF EPIGENETICS, AMONG OTHERS, MAY PROVIDE SOME ANSWERS. THIS REVIEW HENCE EXPLORES THE TEMPORAL ONSET OF THE PATHOLOGICAL FEATURES OF DIABETIC CARDIOMYOPATHY, AND THEIR RELATIVE CONTRIBUTION TO THE RESULTANT DISEASE PHENOTYPE, AS WELL AS BOTH CURRENT AND POTENTIAL THERAPEUTIC OPTIONS. THE EMERGENCE OF GLUCOSE-OPTIMIZING AGENTS, NAMELY GLUCAGON-LIKE PEPTIDE-1 (GLP-1) AGONISTS AND SODIUM/GLUCOSE CO-TRANSPORTER (SGLT)2 INHIBITORS THAT CONFER BENEFITS ON CARDIOVASCULAR OUTCOMES, TOGETHER WITH NOVEL EXPERIMENTAL APPROACHES, HIGHLIGHT A NEW AND EXCITING ERA IN DIABETES RESEARCH, WHICH IS LIKELY TO RESULT IN MAJOR CLINICAL IMPACT. 2017 18 1066 39 CLINICAL USE OF AMINO ACIDS AS DIETARY SUPPLEMENT: PROS AND CONS. NITROGEN SUPPLY IS PIVOTAL FOR THE MAINTENANCE OF LIFE. AMINO ACIDS CAN BE UTILIZED TO SYNTHESIZE BOTH GLUCOSE AND LIPIDS. THE OPPOSITE, I.E., PRODUCTION OF AMINO ACIDS FROM EITHER ONE OF THEM, IS NOT POSSIBLE IN THE ABSENCE OF OTHER AMINO ACIDS AS DONORS OF NITROGEN. THE QUALITY OF AMINO ACID CONTENT IN PROTEIN HAS BEEN RE-EVALUATED RECENTLY, AND THE RELEVANCE OF ESSENTIAL AMINO ACIDS HAS BEEN REPEATEDLY UNDERLINED. ESSENTIAL AMINO ACID REQUIREMENTS IN DIFFERENT MAMMALS ARE NOT IDENTICAL, AND RATIOS AMONG THEM SHOULD BE TAKEN INTO ACCOUNT WHEN PROJECTING AN EFFICIENT FORMULATION. RECENT RESEARCH HAS DEMONSTRATED THAT GENES RESPOND TO DIFFERENT QUALITIES AND QUANTITIES OF NUTRITIONAL SUPPLY, AND INCREASED PROVISION OF ESSENTIAL AMINO ACIDS INCREASES LIFESPAN IN ANIMAL EXPERIMENTS THROUGH MITOCHONDRIOGENESIS AND MAINTENANCE OF ELEVATED RATES OF SYNTHESIS OF ANTI-OXIDANT MOLECULES. MOREOVER, GENETIC EXPRESSION OF KEY CONTROLLERS OF SYNTHESIS, LIKE MTOR, MAY BE PARTICULARLY IMPORTANT FOR UNDERSTANDING SKELETAL MUSCLE MAINTENANCE. LOSSES OF MUSCLE MASS AND IMPAIRED IMMUNE FUNCTION ARE RELATED TO REDUCED PROTEIN SUPPLY, AND THERE IS INCREASING EVIDENCE THAT REGULAR ESSENTIAL AMINO ACID INTAKE AS PART OF AN ORAL DIET IS EFFECTIVE IN REVERSING MUSCLE CATABOLISM, PROMOTING MUSCLE ANABOLISM, AND RESTORING IMMUNOLOGICAL FUNCTION. THEREFORE, THE USE OF AMINO ACIDS AS SUPPLEMENTS TO DIET WOULD BE EXPANDING IN THE NEAR FUTURE. IS THIS SAFE? FEW DATA ARE AVAILABLE ON AMINO ACID TOXICITY, AND ONLY ONE ESSENTIAL AMINO ACID MAY BE CONSIDERED TO HAVE CLINICALLY RELEVANT TOXICITY: METHIONINE, BECAUSE IT IS TRANSFORMED INTO A TOXIC INTERMEDIATE, HOMOCYSTEINE, WHEN CYSTEINE SYNTHESIS IS REQUIRED BY METABOLIC NEEDS. MATCHING OF STOICHIOMETRIC RATIOS BETWEEN METHIONINE AND CYSTEINE MAY SOLVE THE PROBLEM OF SUPPLYING SUFFICIENT AMOUNTS OF SULFUR TO THE BODY. ARGININE AND GLUTAMINE ARE TWO NON-ESSENTIAL AMINO ACIDS THAN CAN BECOME "CONDITIONALLY ESSENTIAL" BECAUSE OF ELEVATED NEEDS DURING PATHOLOGICAL CONDITIONS, AND METABOLISM MAY NOT BE ABLE TO MAINTAIN THEIR CONCENTRATIONS AT SUFFICIENT LEVELS TO MATCH METABOLIC REQUIREMENTS. CHRONIC EXOGENOUS ARGININE SUPPLEMENTATION HAS NOT PROVEN TO EXERT POSITIVE CLINICAL EFFECTS IN DIFFERENT TRIALS, AND SEQUENTIAL ARTICULATION OF THE KNOWLEDGE OF INTRODUCTION OF ARGININE-DRIVEN TRANSCRIPTIONAL, TRANSLATIONAL, AND EPIGENETIC ADAPTATIONS MAY GIVE US A KEY FOR INTERPRETING THOSE PUZZLING RESULTS. 2011 19 4711 31 NON-ALCOHOLIC FATTY LIVER DISEASE IN OBESE CHILDREN AND ADOLESCENTS: A ROLE FOR NUTRITION? NON-ALCOHOLIC FATTY LIVER DISEASE (NAFLD) HAS BECOME THE MOST COMMON CAUSE OF CHRONIC LIVER DISEASE IN CHILDREN, PARALLELING THE INCREASING PREVALENCE OF OBESITY WORLDWIDE. THE PATHOGENESIS OF PAEDIATRIC NAFLD IS NOT FULLY UNDERSTOOD, BUT IT IS KNOWN THAT OBESITY, NUTRITION, LIFESTYLE VARIABLES, GENETIC AND EPIGENETIC FACTORS MAY BE CAUSALLY INVOLVED IN THE DEVELOPMENT OF THIS COMMON METABOLIC LIVER DISEASE. IN PARTICULAR, OBESITY AND NUTRITION ARE AMONG THE STRONGEST RISK FACTORS FOR PAEDIATRIC NAFLD, WHICH MAY EXERT THEIR ADVERSE HEPATIC EFFECTS ALREADY BEFORE BIRTH. EXCESS ENERGY INTAKE INDUCES HYPERTROPHY AND HYPERPLASIA OF ADIPOSE TISSUE WITH SUBSEQUENT DEVELOPMENT OF SYSTEMIC INSULIN RESISTANCE, WHICH IS ANOTHER IMPORTANT RISK FACTOR FOR NAFLD. DIET COMPOSITION AND IN PARTICULAR SIMPLE CARBOHYDRATE INTAKE (ESPECIALLY HIGH FRUCTOSE INTAKE) MAY PROMOTE THE DEVELOPMENT OF NAFLD, WHEREAS NON-DIGESTIBLE CARBOHYDRATES (DIETARY FIBER), BY AFFECTING GUT MICROBIOTA, MAY FAVOUR THE INTEGRITY OF GUT WALL AND REDUCE INFLAMMATION, OPPOSING THIS PROCESS. SATURATED FAT INTAKE MAY ALSO PROMOTE NAFLD DEVELOPMENT, WHEREAS UNSATURATED FAT INTAKE HAS SOME BENEFICIAL EFFECTS. PROTEIN INTAKE DOES NOT SEEM TO AFFECT THE DEVELOPMENT OF NAFLD, BUT FURTHER INVESTIGATION IS NEEDED. IN CONCLUSION, LIFESTYLE MODIFICATIONS TO INDUCE WEIGHT LOSS, THROUGH DIET AND PHYSICAL ACTIVITY, REMAIN THE MAINSTAY OF TREATMENT FOR PAEDIATRIC NAFLD. THE USE OF DIETARY SUPPLEMENTS, SUCH AS OMEGA-3 FATTY ACIDS AND PROBIOTICS, NEEDS FURTHER STUDY BEFORE RECOMMENDATION. 2022 20 5327 19 PULSED GLUCOCORTICOIDS ENHANCE DYSTROPHIC MUSCLE PERFORMANCE THROUGH EPIGENETIC-METABOLIC REPROGRAMMING. IN HUMANS, CHRONIC GLUCOCORTICOID USE IS ASSOCIATED WITH SIDE EFFECTS LIKE MUSCLE WASTING, OBESITY, AND METABOLIC SYNDROME. INTERMITTENT STEROID DOSING HAS BEEN PROPOSED IN DUCHENNE MUSCULAR DYSTROPHY PATIENTS TO MITIGATE THE SIDE EFFECTS SEEN WITH DAILY STEROID INTAKE. WE EVALUATED BIOMARKERS FROM DUCHENNE MUSCULAR DYSTROPHY PATIENTS, FINDING THAT, COMPARED WITH CHRONIC DAILY STEROID USE, WEEKEND STEROID USE WAS ASSOCIATED WITH REDUCED SERUM INSULIN, FREE FATTY ACIDS, AND BRANCHED CHAIN AMINO ACIDS, AS WELL AS REDUCTION IN FAT MASS DESPITE HAVING SIMILAR BMIS. WE REASONED THAT INTERMITTENT PREDNISONE ADMINISTRATION IN DYSTROPHIC MICE WOULD ALTER MUSCLE EPIGENOMIC SIGNATURES, AND WE IDENTIFIED THE COORDINATED ACTION OF THE GLUCOCORTICOID RECEPTOR, KLF15 AND MEF2C AS MEDIATORS OF A GENE EXPRESSION PROGRAM DRIVING METABOLIC REPROGRAMMING AND ENHANCED NUTRIENT UTILIZATION. MUSCLE LACKING KLF15 FAILED TO RESPOND TO INTERMITTENT STEROIDS. FURTHERMORE, COADMINISTRATION OF THE HISTONE ACETYLTRANSFERASE INHIBITOR ANACARDIC ACID WITH STEROIDS IN MDX MICE ELIMINATED STEROID-SPECIFIC EPIGENETIC MARKS AND ABROGATED THE STEROID RESPONSE. TOGETHER, THESE FINDINGS INDICATE THAT INTERMITTENT, REPEATED EXPOSURE TO GLUCOCORTICOIDS PROMOTES PERFORMANCE IN DYSTROPHIC MUSCLE THROUGH AN EPIGENETIC PROGRAM THAT ENHANCES NUTRIENT UTILIZATION. 2019