1 72 153 A MOLECULAR SIGNATURE FOR DELAYED GRAFT FUNCTION. CHRONIC KIDNEY DISEASE AND ASSOCIATED COMORBIDITIES (DIABETES, CARDIOVASCULAR DISEASES) MANIFEST WITH AN ACCELERATED AGEING PHENOTYPE, LEADING ULTIMATELY TO ORGAN FAILURE AND RENAL REPLACEMENT THERAPY. THIS PROCESS CAN BE MODULATED BY EPIGENETIC AND ENVIRONMENTAL FACTORS WHICH PROMOTE LOSS OF PHYSIOLOGICAL FUNCTION AND RESILIENCE TO STRESS EARLIER, LINKING BIOLOGICAL AGE WITH ADVERSE OUTCOMES POST-TRANSPLANTATION INCLUDING DELAYED GRAFT FUNCTION (DGF). THE MOLECULAR FEATURES UNDERPINNING THIS HAVE YET TO BE FULLY ELUCIDATED. WE HAVE DETERMINED A MOLECULAR SIGNATURE FOR LOSS OF RESILIENCE AND IMPAIRED PHYSIOLOGICAL FUNCTION, VIA A SYNCHRONOUS GENOME, TRANSCRIPTOME AND PROTEOME SNAPSHOT, USING HUMAN RENAL ALLOGRAFTS AS A SOURCE OF HEALTHY TISSUE AS AN IN VIVO MODEL OF AGEING IN HUMANS. THIS COMPRISES 42 SPECIFIC TRANSCRIPTS, RELATED THROUGH IFNGAMMA SIGNALLING, WHICH IN ALLOGRAFTS DISPLAYING CLINICALLY IMPAIRED PHYSIOLOGICAL FUNCTION (DGF) EXHIBITED A GREATER MAGNITUDE OF CHANGE IN TRANSCRIPTIONAL AMPLITUDE AND ELEVATED EXPRESSION OF NONCODING RNAS AND PSEUDOGENES, CONSISTENT WITH INCREASED ALLOSTATIC LOAD. THIS WAS ACCOMPANIED BY INCREASED DNA METHYLATION WITHIN THE PROMOTER AND INTRAGENIC REGIONS OF THE DGF PANEL IN PREPERFUSION ALLOGRAFTS WITH IMMEDIATE GRAFT FUNCTION. PATHWAY ANALYSIS INDICATED THAT AN INABILITY TO SUFFICIENTLY RESOLVE INFLAMMATORY RESPONSES WAS ENABLED BY DECREASED RESILIENCE TO STRESS AND RESULTED IN IMPAIRED PHYSIOLOGICAL FUNCTION IN BIOLOGICALLY OLDER ALLOGRAFTS. CROSS-COMPARISON WITH PUBLICALLY AVAILABLE DATA SETS FOR RENAL PATHOLOGIES IDENTIFIED SIGNIFICANT TRANSCRIPTIONAL COMMONALITY FOR OVER 20 DGF TRANSCRIPTS. OUR DATA ARE CLINICALLY RELEVANT AND IMPORTANT, AS THEY PROVIDE A CLEAR MOLECULAR SIGNATURE FOR THE BURDEN OF "WEAR AND TEAR" WITHIN THE KIDNEY AND THUS AGE-RELATED PHYSIOLOGICAL CAPABILITY AND RESILIENCE. 2018 2 4148 35 MECHANISTIC BASIS OF EX VIVO UMBILICAL CORD BLOOD STEM PROGENITOR CELL EXPANSION. UMBILICAL CORD BLOOD (CB) TRANSPLANTATION HAS BEEN USED SUCCESSFULLY IN HUMANS FOR THREE DECADES DUE TO ITS RAPID AVAILABILITY FOR PATIENTS LACKING A SUITABLE ALLOGENEIC DONOR, LESS STRINGENT HLA MATCHING REQUIREMENTS, AND LOW RATES OF RELAPSE AND CHRONIC GRAFT-VERSUS-HOST DISEASE (GVHD). HOWEVER, CB TRANSPLANTATION IS ASSOCIATED WITH COMPLICATIONS, SUCH AS DELAYED HEMATOPOIETIC ENGRAFTMENT, GRAFT FAILURE, WHICH INCREASES INFECTION AND BLEEDING AND CAUSES LONGER HOSPITAL STAYS, AND TRANSPLANT-RELATED MORTALITY. THE MAJORITY OF THESE BIOLOGICAL LIMITATIONS ARE DUE TO THE UNFORESEEABLE FUNCTIONAL POTENCY OF MULTIPOTENT HEMATOPOIETIC STEM CELLS (HSCS), WHICH REDUCE THE PREDICTABILITY OF SUCCESSFUL TRANSPLANTATION; HOWEVER, SEVERAL STRATEGIES HAVE BEEN DEVELOPED TO INCREASE THE NUMBER OF HEMATOPOIETIC STEM PROGENITOR CELLS (HSPCS) INFUSED DURING CB TRANSPLANTATION. THIS REVIEW PRIMARILY ADDRESSES THE METHODS THAT PROMOTE EX VIVO CB EXPANSION WITHIN THE CONTEXT OF SYMMETRICAL AND ASYMMETRICAL HSC DIVISION AND THOSE THAT RELY ON EPIGENETIC MECHANISMS, ALONG WITH THE REPORTEDLY MOST SUCCESSFUL CYTOKINE COMBINATIONS. WE ALSO REVIEW RECENT CLINICAL RESEARCH ON SMALL MOLECULES (STEMREGENIN-1, UM171, AND NICOTINAMIDE) IN EX VIVO EXPANDED CB AND DISCUSS YET UNVALIDATED PRECLINICAL STRATEGIES. EXPANDING AND TRANSPLANTING CB GRAFT ENRICHED IN HSPCS IN A SINGLE CB UNIT IS A PARTICULARLY EXCITING PROSPECT WITH THE POTENTIAL TO IMPROVE THE USE AND AVAILABILITY OF CB GRAFTS. GREATER KNOWLEDGE OF OPTIMAL EX VIVO EXPANSION STRATEGIES, CELL LONGEVITY, AND GRAFT POTENCY WILL EXPAND THE SCOPE OF CELLULAR THERAPIES. ALSO THE DEVELOPMENT OF ADEQUATE EX VIVO HSPC EXPANSION STRATEGIES COULD BRING EXPANDED CORD BLOOD GRAFTS TO THE FOREFRONT OF TRANSPLANT THERAPY AND REGENERATIVE MEDICINE. 2020 3 3856 39 ISCHAEMIA REPERFUSION INJURY: MECHANISMS OF PROGRESSION TO CHRONIC GRAFT DYSFUNCTION. THE INCREASING USE OF EXTENDED CRITERIA ORGANS TO MEET THE DEMAND FOR KIDNEY TRANSPLANTATION RAISES AN IMPORTANT QUESTION OF HOW THE SEVERITY OF EARLY ISCHAEMIC INJURY INFLUENCES LONG-TERM OUTCOMES. SIGNIFICANT ACUTE ISCHAEMIC KIDNEY INJURY IS ASSOCIATED WITH DELAYED GRAFT FUNCTION, INCREASED IMMUNE-ASSOCIATED EVENTS AND, ULTIMATELY, EARLIER DETERIORATION OF GRAFT FUNCTION. A COMPREHENSIVE UNDERSTANDING OF IMMEDIATE MOLECULAR EVENTS THAT ENSUE POST-ISCHAEMIA AND THEIR POTENTIAL LONG-TERM CONSEQUENCES ARE KEY TO THE DISCOVERY OF NOVEL THERAPEUTIC TARGETS. ACUTE ISCHAEMIC INJURY PRIMARILY AFFECTS TUBULAR STRUCTURE AND FUNCTION. DEPENDING ON THE SEVERITY AND PERSISTENCE OF THE INSULT, THIS MAY RESOLVE COMPLETELY, LEADING TO RESTORATION OF NORMAL FUNCTION, OR BE SUSTAINED, RESULTING IN PERSISTENT RENAL IMPAIRMENT AND PROGRESSIVE FUNCTIONAL LOSS. LONG-TERM EFFECTS OF ACUTE RENAL ISCHAEMIA ARE MEDIATED BY SEVERAL MECHANISMS INCLUDING HYPOXIA, HIF-1 ACTIVATION, ENDOTHELIAL DYSFUNCTION LEADING TO VASCULAR RAREFACTION, SUSTAINED PRO-INFLAMMATORY STIMULI INVOLVING INNATE AND ADAPTIVE IMMUNE RESPONSES, FAILURE OF TUBULAR CELLS TO RECOVER AND EPIGENETIC CHANGES. THIS REVIEW DESCRIBES THE BIOLOGICAL RELEVANCE AND INTERACTION OF THESE MECHANISMS BASED ON CURRENTLY AVAILABLE EVIDENCE. 2019 4 621 36 BIOENERGETIC EVOLUTION EXPLAINS PREVALENCE OF LOW NEPHRON NUMBER AT BIRTH: RISK FACTOR FOR CKD. THERE IS GREATER THAN TENFOLD VARIATION IN NEPHRON NUMBER OF THE HUMAN KIDNEY AT BIRTH. ALTHOUGH LOW NEPHRON NUMBER IS A RECOGNIZED RISK FACTOR FOR CKD, ITS DETERMINANTS ARE POORLY UNDERSTOOD. EVOLUTIONARY MEDICINE REPRESENTS A NEW DISCIPLINE THAT SEEKS EVOLUTIONARY EXPLANATIONS FOR DISEASE, BROADENING PERSPECTIVES ON RESEARCH AND PUBLIC HEALTH INITIATIVES. EVOLUTION OF THE KIDNEY, AN ORGAN RICH IN MITOCHONDRIA, HAS BEEN DRIVEN BY NATURAL SELECTION FOR REPRODUCTIVE FITNESS CONSTRAINED BY ENERGY AVAILABILITY. OVER THE PAST 2 MILLION YEARS, RAPID GROWTH OF AN ENERGY-DEMANDING BRAIN IN HOMO SAPIENS ENABLED HOMINID ADAPTATION TO ENVIRONMENTAL EXTREMES THROUGH SELECTION FOR MUTATIONS IN MITOCHONDRIAL AND NUCLEAR DNA EPIGENETICALLY REGULATED BY ALLOCATION OF ENERGY TO DEVELOPING ORGANS. MATERNAL UNDERNUTRITION OR HYPOXIA RESULTS IN INTRAUTERINE GROWTH RESTRICTION OR PRETERM BIRTH, RESULTING IN LOW BIRTH WEIGHT AND LOW NEPHRON NUMBER. REGULATED THROUGH PLACENTAL TRANSFER, ENVIRONMENTAL OXYGEN AND NUTRIENTS SIGNAL NEPHRON PROGENITOR CELLS TO REPROGRAM METABOLISM FROM GLYCOLYSIS TO OXIDATIVE PHOSPHORYLATION. THESE PROCESSES ARE MODULATED BY COUNTERBALANCING ANABOLIC AND CATABOLIC METABOLIC PATHWAYS THAT EVOLVED FROM PROKARYOTE HOMOLOGS AND BY HYPOXIA-DRIVEN AND AUTOPHAGY PATHWAYS THAT EVOLVED IN EUKARYOTES. REGULATION OF NEPHRON DIFFERENTIATION BY HISTONE MODIFICATIONS AND DNA METHYLTRANSFERASES PROVIDE EPIGENETIC CONTROL OF NEPHRON NUMBER IN RESPONSE TO ENERGY AVAILABLE TO THE FETUS. DEVELOPMENTAL PLASTICITY OF NEPHROGENESIS REPRESENTS AN EVOLVED LIFE HISTORY STRATEGY THAT PRIORITIZES ENERGY TO EARLY BRAIN GROWTH WITH ADEQUATE KIDNEY FUNCTION THROUGH REPRODUCTIVE YEARS, THE TRADE-OFF BEING INCREASING PREVALENCE OF CKD DELAYED UNTIL LATER ADULTHOOD. THE RESEARCH IMPLICATIONS OF THIS EVOLUTIONARY ANALYSIS ARE TO IDENTIFY REGULATORY PATHWAYS OF ENERGY ALLOCATION DIRECTING NEPHROGENESIS WHILE ACCOUNTING FOR THE DIFFERENT LIFE HISTORY STRATEGIES OF ANIMAL MODELS SUCH AS THE MOUSE. THE CLINICAL IMPLICATIONS ARE TO OPTIMIZE NUTRITION AND MINIMIZE HYPOXIC/TOXIC STRESSORS IN CHILDBEARING WOMEN AND CHILDREN IN EARLY POSTNATAL DEVELOPMENT. 2020 5 1066 35 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 6 1469 33 DISTINCT EVOLUTIONARY PATHS IN CHRONIC LYMPHOCYTIC LEUKEMIA DURING RESISTANCE TO THE GRAFT-VERSUS-LEUKEMIA EFFECT. LEUKEMIC RELAPSE REMAINS A MAJOR BARRIER TO SUCCESSFUL ALLOGENEIC HEMATOPOIETIC STEM CELL TRANSPLANTATION (ALLO-HSCT) FOR AGGRESSIVE HEMATOLOGIC MALIGNANCIES. THE BASIS FOR RELAPSE OF ADVANCED LYMPHOID MALIGNANCIES REMAINS INCOMPLETELY UNDERSTOOD AND MAY INVOLVE ESCAPE FROM THE GRAFT-VERSUS-LEUKEMIA (GVL) EFFECT. WE HYPOTHESIZED THAT FOR PATIENTS WITH CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) TREATED WITH ALLO-HSCT, LEUKEMIC CELL-INTRINSIC FEATURES INFLUENCE TRANSPLANT OUTCOMES BY DIRECTING THE EVOLUTIONARY TRAJECTORIES OF CLL CELLS. INTEGRATED GENETIC, TRANSCRIPTOMIC, AND EPIGENETIC ANALYSES OF CLL CELLS FROM 10 PATIENTS REVEALED THAT THE CLINICAL KINETICS OF POST-HSCT RELAPSE ARE SHAPED BY DISTINCT MOLECULAR DYNAMICS. EARLY RELAPSES AFTER ALLO-HSCT EXHIBITED NOTABLE GENETIC STABILITY; SINGLE CLL CELL TRANSCRIPTIONAL ANALYSIS DEMONSTRATED A CELLULAR HETEROGENEITY THAT WAS STATIC OVER TIME. IN CONTRAST, CLL CELLS RELAPSING LATE AFTER ALLO-HSCT DISPLAYED NOTABLE GENETIC EVOLUTION AND EVIDENCE OF NEOANTIGEN DEPLETION, CONSISTENT WITH MARKED SINGLE-CELL TRANSCRIPTIONAL SHIFTS THAT WERE UNIQUE TO EACH PATIENT. WE OBSERVED A GREATER RATE OF EPIGENETIC CHANGE FOR LATE RELAPSES NOT SEEN IN EARLY RELAPSES OR RELAPSES AFTER CHEMOTHERAPY ALONE, SUGGESTING THAT THE SELECTION PRESSURES OF THE GVL BOTTLENECK ARE UNLIKE THOSE IMPOSED BY CHEMOTHERAPY. NO SELECTIVE ADVANTAGE FOR HUMAN LEUKOCYTE ANTIGEN (HLA) LOSS WAS OBSERVED, EVEN WHEN PRESENT IN PRETRANSPLANT SUBPOPULATIONS. GAIN OF STEM CELL MODULES WAS A COMMON SIGNATURE ASSOCIATED WITH LEUKEMIA RELAPSE REGARDLESS OF POSTTRANSPLANT RELAPSE KINETICS. THESE DATA ELUCIDATE THE BIOLOGICAL PATHWAYS THAT UNDERLIE GVL RESISTANCE AND POSTTRANSPLANT RELAPSE. 2020 7 4856 34 OPTIMIZING RETROVIRAL GENE EXPRESSION FOR EFFECTIVE THERAPIES. WITH THEIR ABILITY TO INTEGRATE THEIR GENETIC MATERIAL INTO THE TARGET CELL GENOME, RETROVIRAL VECTORS (RV) OF BOTH THE GAMMA-RETROVIRAL (GAMMA-RV) AND LENTIVIRAL VECTOR (LV) CLASSES CURRENTLY REMAIN THE MOST EFFICIENT AND THUS THE SYSTEM OF CHOICE FOR ACHIEVING TRANSGENE RETENTION AND THEREFORE POTENTIALLY LONG-TERM EXPRESSION AND THERAPEUTIC BENEFIT. HOWEVER, GAMMA-RV AND LV INTEGRATION COMES AT A COST IN THAT TRANSCRIPTION UNITS WILL BE PRESENT WITHIN A NATIVE CHROMATIN ENVIRONMENT AND THUS BE SUBJECT TO EPIGENETIC EFFECTS (DNA METHYLATION, HISTONE MODIFICATIONS) THAT CAN NEGATIVELY IMPACT ON THEIR FUNCTION. INDEED, HIGHLY VARIABLE EXPRESSION AND SILENCING OF GAMMA-RV AND LV TRANSGENES ESPECIALLY RESULTING FROM PROMOTER DNA METHYLATION IS WELL DOCUMENTED AND WAS THE CAUSE OF THE FAILURE OF GENE THERAPY IN A CLINICAL TRIAL FOR X-LINKED CHRONIC GRANULOMATOUS DISEASE. THIS REVIEW WILL CRITICALLY EXPLORE THE USE OF DIFFERENT CLASSES OF GENETIC CONTROL ELEMENTS THAT CAN IN PRINCIPLE REDUCE VECTOR INSERTION SITE POSITION EFFECTS AND EPIGENETIC-MEDIATED SILENCING. THESE TRANSCRIPTIONAL REGULATORY ELEMENTS BROADLY DIVIDE THEMSELVES INTO EITHER THOSE WITH A CHROMATIN BOUNDARY OR BORDER FUNCTION (SCAFFOLD/MATRIX ATTACHMENT REGIONS, INSULATORS) OR THOSE WITH A DOMINANT CHROMATIN REMODELING AND TRANSCRIPTIONAL ACTIVATING CAPABILITY (LOCUS CONTROL REGIONS,, UBIQUITOUS CHROMATIN OPENING ELEMENTS). ALL THESE TYPES OF ELEMENTS HAVE THEIR STRENGTHS AND WEAKNESSES WITHIN THE CONSTRAINTS OF A GAMMA-RV AND LV BACKBONE, SHOWING VARYING DEGREES OF EFFICACY IN IMPROVING REPRODUCIBILITY AND STABILITY OF TRANSGENE FUNCTION. COMBINATIONS OF BOUNDARY AND CHROMATIN REMODELING; TRANSCRIPTIONAL ACTIVATING ELEMENTS, WHICH DO NOT IMPEDE VECTOR PRODUCTION; TRANSDUCTION EFFICIENCY; AND STABILITY ARE MOST LIKELY TO MEET THE REQUIREMENTS WITHIN A GENE THERAPY CONTEXT ESPECIALLY WHEN TARGETING A STEM CELL POPULATION. 2013 8 5985 39 TET2-MEDIATED CLONAL HEMATOPOIESIS ACCELERATES HEART FAILURE THROUGH A MECHANISM INVOLVING THE IL-1BETA/NLRP3 INFLAMMASOME. BACKGROUND: RECENT STUDIES HAVE SHOWN THAT HEMATOPOIETIC STEM CELLS CAN UNDERGO CLONAL EXPANSION SECONDARY TO SOMATIC MUTATIONS IN LEUKEMIA-RELATED GENES, THUS LEADING TO AN AGE-DEPENDENT ACCUMULATION OF MUTANT LEUKOCYTES IN THE BLOOD. THIS SOMATIC MUTATION-RELATED CLONAL HEMATOPOIESIS IS COMMON IN HEALTHY OLDER INDIVIDUALS, BUT IT HAS BEEN ASSOCIATED WITH AN INCREASED INCIDENCE OF FUTURE CARDIOVASCULAR DISEASE. THE EPIGENETIC REGULATOR TET2 IS FREQUENTLY MUTATED IN BLOOD CELLS OF INDIVIDUALS EXHIBITING CLONAL HEMATOPOIESIS. OBJECTIVES: THIS STUDY INVESTIGATED WHETHER TET2 MUTATIONS WITHIN HEMATOPOIETIC CELLS CAN CONTRIBUTE TO HEART FAILURE IN 2 MODELS OF CARDIAC INJURY. METHODS: HEART FAILURE WAS INDUCED IN MICE BY PRESSURE OVERLOAD, ACHIEVED BY TRANSVERSE AORTIC CONSTRICTION OR CHRONIC ISCHEMIA INDUCED BY THE PERMANENT LIGATION OF THE LEFT ANTERIOR DESCENDING ARTERY. COMPETITIVE BONE MARROW TRANSPLANTATION STRATEGIES WITH TET2-DEFICIENT CELLS WERE USED TO MIMIC TET2 MUTATION-DRIVEN CLONAL HEMATOPOIESIS. ALTERNATIVELY, TET2 WAS SPECIFICALLY ABLATED IN MYELOID CELLS USING CRE RECOMBINASE EXPRESSED FROM THE LYSM PROMOTER. RESULTS: IN BOTH EXPERIMENTAL HEART FAILURE MODELS, HEMATOPOIETIC OR MYELOID TET2 DEFICIENCY WORSENED CARDIAC REMODELING AND FUNCTION, IN PARALLEL WITH INCREASED INTERLEUKIN-1BETA (IL-1BETA) EXPRESSION. TREATMENT WITH A SELECTIVE NLRP3 INFLAMMASOME INHIBITOR PROTECTED AGAINST THE DEVELOPMENT OF HEART FAILURE AND ELIMINATED THE DIFFERENCES IN CARDIAC PARAMETERS BETWEEN TET2-DEFICIENT AND WILD-TYPE MICE. CONCLUSIONS: TET2 DEFICIENCY IN HEMATOPOIETIC CELLS IS ASSOCIATED WITH GREATER CARDIAC DYSFUNCTION IN MURINE MODELS OF HEART FAILURE AS A RESULT OF ELEVATED IL-1BETA SIGNALING. THESE DATA SUGGEST THAT INDIVIDUALS WITH TET2-MEDIATED CLONAL HEMATOPOIESIS MAY BE AT GREATER RISK OF DEVELOPING HEART FAILURE AND RESPOND BETTER TO IL-1BETA-NLRP3 INFLAMMASOME INHIBITION. 2018 9 750 17 CARDIAC INVOLVEMENT IN PATIENTS WITH HEMATOLOGIC MALIGNANCIES. AUTHORS HAVE REVIEWED LITERATURE ABOUT THE MANAGEMENT OF PATIENTS WITH CARDIOLOGIC DISEASE OCCURRING SECONDARY TO HEMATOLOGIC PATHOLOGY ITSELF OR ITS THERAPY, WITH A FOCUS ON INFILTRATION OF MYOCARDIUM IN ACUTE AND CHRONIC LEUKEMIA, LYMPHOMA, MULTIPLE MYELOMA, AND HYPEREOSINOPHILIC SYNDROME. MOREOVER, THEY EVALUATED CHEMOTHERAPY-ASSOCIATED TOXICITY, PARTICULARLY FOR NEW DRUGS SUCH AS MONOCLONAL ANTIBODY THERAPY, TYROSINE KINASE INHIBITORS, ARSENIC TRIOXIDE, BORTEZOMIB, AND EPIGENETIC THERAPY. IN FACT, CARDIAC TOXICITY MAY RANGE FROM ASYMPTOMATIC SUBCLINICAL ABNORMALITIES, SUCH AS ELECTROCARDIOGRAPHIC CHANGES AND LEFT VENTRICULAR EJECTION DECLINE, TO LIFE-THREATENING EVENTS AND LEAD TO CHEMOTHERAPY DOSE REDUCTION AND DELAY AND, IN SOME CASES, FOR PATIENTS WITH SEVERE SIDE EFFECTS, DISCONTINUATION OF TREATMENT. FINALLY, THEY DISCUSSED ON THE IDENTIFICATION OF EARLY MARKERS OF CARDIAC INJURY AND ON CARDIAC STEM CELL THERAPY AS A PROMISING APPROACH TO FACILITATE MYOCARDIAL REGENERATION. 2010 10 3934 36 LIVER TUMOR INDUCTION. THE SIGNIFICANCE OF THE DEVELOPMENT OF NODULAR LIVER LESIONS IN RODENTS FOLLOWING THE ADMINISTRATION OF TEST AGENTS RAISES SEVERAL QUESTIONS WHICH COULD BE PLACED IN ONE OF TWO GENERAL CATEGORIES: DIAGNOSTIC AND INTERPRETATIONAL. FROM A DIAGNOSTIC POINT OF VIEW, THE PROPER CLASSIFICATION OF LIVER TUMORS INTO A BENIGN AND MALIGNANT CATEGORY HAS TO BE BASED ON THE DIRECT CORRELATION BETWEEN THE MORPHOLOGY AND THE BIOLOGIC BEHAVIOR OF THE LESIONS. THEREFORE, EXTREME CARE SHOULD BE TAKEN TO SEPARATE THE MALIGNANT TUMORS FROM THE BENIGN AND THE BENIGN NEOPLASIA FROM THE HYPERPLASIA. THE SUBSTITUTION OF THE TERM "NEOPLASTIC NODULE" FOR HYPERPLASTIC NODULE IN RATS IS MISLEADING. MOST OF THESE NODULES, WHEN INDUCED UNDER SPECIAL EXPERIMENTAL CONDITIONS, MAY REGRESS OR REMODEL AND THUS THEY ARE NOT NEOPLASTIC IN NATURE. CHRONIC CARCINOGENICITY BIOASSAYS SHOULD INCLUDE "STOP" TYPE OF TREATMENT LEAVING ENOUGH OF THE OBSERVATIONAL TIME TO ESTABLISH THE FATE OF INDUCED NODULAR LESIONS. THE INDUCTION OF HISTOCHEMICALLY CHANGED FOCI CAN SERVE ONLY AS AN INDICATION OF POTENTIAL HEPATOCARCINOGENICITY AND SHOULD NOT BE EQUATED WITH THE INDUCTION OF BONA FIDE CANCER. THE BIOLOGIC INTERPRETATION OF NODULAR LIVER LESIONS, ESPECIALLY IN MICE, NEEDS FURTHER SCRUTINY BECAUSE THESE LESIONS HAVE A TENDENCY TO DEVELOP SPONTANEOUSLY WITH HIGH INCIDENCE IN SOME STRAINS. THIS CHARACTERISTIC THEN RAISES THE QUESTION AS TO THE MECHANISM BY WHICH VARIOUS AGENTS AUGMENT AND/OR ACCELERATE THE DEVELOPMENT OF SUCH TUMORS. IS THIS ACTION PRIMARILY PROMOTING OR INITIATING IN NATURE OR DOES IT REPRESENT THE INDUCTION OF TUMORS DE NOVO? THE ANSWER TO THIS DILEMMA MAY HAVE A DECISIVE BEARING ON CARCINOGENIC RISK ASSESSMENT AND THE TYPE OF REGULATORY ACTION, SINCE THE PROMOTING AGENTS POSSESS A THRESHOLD EFFECT AND THE PROMOTED CHANGES MAY REGRESS FOLLOWING WITHDRAWAL OF TREATMENT. THE INTERPRETATION OF HEPATOCARCINOGENESIS IS FURTHER COMPLICATED BY THE FACT THAT SEVERAL FACTORS, SUCH AS SEX HORMONAL ENVIRONMENT, INCREASED MITOTIC ACTIVITY FOLLOWING AN EXCESSIVE LOSS OF PARENCHYMAL CELLS, DEGREE OF CALORIC INTAKE, ENZYMATIC COMPLEMENT, AND ANIMALS' AGE AT THE TIME OF THE EXPOSURE TO A TEST AGENT, MAY INFLUENCE THE OUTCOME OF LIVER TUMOR DEVELOPMENT BY MODULATING "INITIATION" AND/OR "PROMOTION" OF CARCINOGENESIS. BROAD FLUCTUATION IN THE HISTORIC INCIDENCE OF LIVER TUMORS FURTHER COMPOUNDS THE COMPLEXITY OF THE PROPER BIOASSAY INTERPRETATION. THE SPECIFICALLY DESIGNED EXPERIMENTS MAY HAVE THE OBJECTIVE TO EXPLORE PREDOMINANTLY THE INITIATING OR PROMOTING EFFECTS OF THE AGENT. SUCH PROTOCOLS SHOULD BE USED WHENEVER NECESSARY TO DIFFERENTIATE BETWEEN THESE TWO MECHANISMS OF ACTION. IN THE CAUCASIANS, THE "SPONTANEOUS" DEVELOPMENT OF THE PRIMARY HEPATOCELLULAR TUMORS IS RARE. THE MAJORITY OF THESE TUMORS ARE MALIGNANT AND RAPIDLY FATAL. ACCORDING TO SOME HUMAN PATHOLOGISTS, THE BENIGN VARIETY OF LIVER TUMORS IS RARE AND IT DOES NOT REPRESENT NECESSARILY A PREMALIGNANT STAGE IN TUMOR DEVELOPMENT. CARCINOMA OF THE LIVER MAY OCCUR IN INFANCY, ESPECIALLY IN MALES BEFORE THE AGE OF 2 YEARS. THIS SUGGESTS A GENETIC CAUSATION OR CARCINOGENIC EXPOSURE IN UTERO. ONE OF THE GEOGRAPHIC FACTORS WHICH SIGNIFICANTLY ENHANCES THE INCIDENCE OF HEPATOCELLULAR CARCINOMA IN HUMANS IS EXPOSURE TO AFLATOXIN B(1) WHICH IS APPARENTLY POTENTIATED BY CONCURRENT LIVER CIRRHOSIS. BECAUSE MANY MORE AGENTS HAVE BEEN FOUND TO BE HEPATOCARCINOGENIC IN MICE AND RATS THAN IN MEN, A QUESTION ARISES AS TO THE DIRECT RELEVANCE OF RODENT STUDIES TO HUMANS. A BALANCED ASSESSMENT OF THE CARCINOGENICITY OF THE AGENT COULD ONLY BE REACHED IN CONSIDERING BOTH THE PHARMACOKINETICS AND THE DEVELOPMENT OF MALIGNANT NEOPLASIA IN OTHER ORGANS. IN THE CASE OF POSITIVE CARCINOGENICITY ASSESSMENT, THE OUTCOME OF THE MUTAGENICITY BIOASSAYS CAN SUGGEST GENIC (GENOTOXIC) OR PARAGENIC (EPIGENETIC) MODE OF ACTION IN MAMMALIAN SYSTEMS. 1982 11 1887 41 ENDOMETRIAL RECEPTIVITY IN WOMEN OF ADVANCED AGE: AN UNDERRATED FACTOR IN INFERTILITY. BACKGROUND: MODERN LIFESTYLE HAS LED TO AN INCREASE IN THE AGE AT CONCEPTION. ADVANCED AGE IS ONE OF THE CRITICAL RISK FACTORS FOR FEMALE-RELATED INFERTILITY. IT IS WELL KNOWN THAT MATERNAL AGE POSITIVELY CORRELATES WITH THE DETERIORATION OF OOCYTE QUALITY AND CHROMOSOMAL ABNORMALITIES IN OOCYTES AND EMBRYOS. THE EFFECT OF AGE ON ENDOMETRIAL FUNCTION MAY BE AN EQUALLY IMPORTANT FACTOR INFLUENCING IMPLANTATION RATE, PREGNANCY RATE, AND OVERALL FEMALE FERTILITY. HOWEVER, THERE ARE ONLY A FEW PUBLISHED STUDIES ON THIS TOPIC, SUGGESTING THAT THIS AREA HAS BEEN UNDER-EXPLORED. IMPROVING OUR KNOWLEDGE OF ENDOMETRIAL AGING FROM THE BIOLOGICAL (CELLULAR, MOLECULAR, HISTOLOGICAL) AND CLINICAL PERSPECTIVES WOULD BROADEN OUR UNDERSTANDING OF THE RISKS OF AGE-RELATED FEMALE INFERTILITY. OBJECTIVE AND RATIONALE: THE OBJECTIVE OF THIS NARRATIVE REVIEW IS TO CRITICALLY EVALUATE THE EXISTING LITERATURE ON ENDOMETRIAL AGING WITH A FOCUS ON SYNTHESIZING THE EVIDENCE FOR THE IMPACT OF ENDOMETRIAL AGING ON CONCEPTION AND PREGNANCY SUCCESS. THIS WOULD PROVIDE INSIGHTS INTO EXISTING GAPS IN THE CLINICAL APPLICATION OF RESEARCH FINDINGS AND PROMOTE THE DEVELOPMENT OF TREATMENT OPTIONS IN THIS FIELD. SEARCH METHODS: THE REVIEW WAS PREPARED USING PUBMED (MEDLINE) UNTIL FEBRUARY 2023 WITH THE KEYWORDS SUCH AS 'ENDOMETRIAL AGING', 'RECEPTIVITY', 'DECIDUALIZATION', 'HORMONE', 'SENESCENCE', 'CELLULAR', 'MOLECULAR', 'METHYLATION', 'BIOLOGICAL AGE', 'EPIGENETIC', 'OOCYTE RECIPIENT', 'OOCYTE DONATION', 'EMBRYO TRANSFER', AND 'PREGNANCY RATE'. ARTICLES IN A LANGUAGE OTHER THAN ENGLISH WERE EXCLUDED. OUTCOMES: IN THE AGING ENDOMETRIUM, ALTERATIONS OCCUR AT THE MOLECULAR, CELLULAR, AND HISTOLOGICAL LEVELS SUGGESTING THAT AGING HAS A NEGATIVE EFFECT ON ENDOMETRIAL BIOLOGY AND MAY IMPAIR ENDOMETRIAL RECEPTIVITY. ADDITIONALLY, ADVANCED AGE INFLUENCES CELLULAR SENESCENCE, WHICH PLAYS AN IMPORTANT ROLE DURING THE INITIAL PHASE OF IMPLANTATION AND IS A MAJOR OBSTACLE IN THE DEVELOPMENT OF SUITABLE SENOLYTIC AGENTS FOR ENDOMETRIAL AGING. AGING IS ALSO ACCOUNTABLE FOR CHRONIC CONDITIONS ASSOCIATED WITH INFLAMMAGING, WHICH EVENTUALLY CAN LEAD TO INCREASED PRO-INFLAMMATION AND TISSUE FIBROSIS. FURTHERMORE, ADVANCED AGE INFLUENCES EPIGENETIC REGULATION IN THE ENDOMETRIUM, THUS ALTERING THE RELATION BETWEEN ITS EPIGENETIC AND CHRONOLOGICAL AGE. THE STUDIES IN OOCYTE DONATION CYCLES TO DETERMINE THE EFFECT OF AGE ON ENDOMETRIAL RECEPTIVITY WITH RESPECT TO THE RATES OF IMPLANTATION, CLINICAL PREGNANCY, MISCARRIAGE, AND LIVE BIRTH HAVE REVEALED CONTRADICTORY INFERENCES INDICATING THE NEED FOR FUTURE RESEARCH ON THE MECHANISMS AND CORRESPONDING CAUSAL EFFECTS OF WOMEN'S AGE ON ENDOMETRIAL RECEPTIVITY. WIDER IMPLICATIONS: INCREASING AGE CAN BE ACCOUNTABLE FOR FEMALE INFERTILITY AND IVF FAILURES. BASED ON THE COMPLIED OBSERVATIONS AND SYNTHESIZED CONCLUSIONS IN THIS REVIEW, ADVANCED AGE HAS BEEN SHOWN TO HAVE A NEGATIVE IMPACT ON ENDOMETRIAL FUNCTIONING. THIS INFORMATION CAN PROVIDE RECOMMENDATIONS FOR FUTURE RESEARCH FOCUSING ON MOLECULAR MECHANISMS OF AGE-RELATED CELLULAR SENESCENCE, CELLULAR COMPOSITION, AND TRANSCRIPTOMIC CHANGES IN RELATION TO ENDOMETRIAL AGING. ADDITIONALLY, FURTHER PROSPECTIVE RESEARCH IS NEEDED TO EXPLORE NEWLY EMERGING THERAPEUTIC OPTIONS, SUCH AS THE SENOLYTIC AGENTS THAT CAN TARGET ENDOMETRIAL AGING WITHOUT AFFECTING DECIDUALIZATION. MOREOVER, CLINICAL TRIAL PROTOCOLS, FOCUSING ON OOCYTE DONATION CYCLES, WOULD BE BENEFICIAL IN UNDERSTANDING THE DIRECT CLINICAL IMPLICATIONS OF ENDOMETRIAL AGING ON PREGNANCY OUTCOMES. 2023 12 2770 30 EXTENDING INJURY- AND DISEASE-RESISTANT CNS PHENOTYPES BY REPETITIVE EPIGENETIC CONDITIONING. SIGNIFICANT REDUCTIONS IN THE EXTENT OF ACUTE INJURY IN THE CNS CAN BE ACHIEVED BY EXPOSURE TO DIFFERENT PRECONDITIONING STIMULI, BUT THE DURATION OF THE INDUCED PROTECTIVE PHENOTYPE IS TYPICALLY SHORT-LASTING, AND THUS IS DEEMED AS LIMITING ITS CLINICAL APPLICABILITY. EXTENDING THE PERIOD OVER WHICH SUCH ADAPTIVE EPIGENETIC CHANGES PERSIST - IN EFFECT, EXPANDING CONDITIONING'S "THERAPEUTIC WINDOW" - WOULD SIGNIFICANTLY BROADEN THE POTENTIAL APPLICATIONS OF SUCH A TREATMENT APPROACH IN PATIENTS. THE FREQUENCY OF THE CONDITIONING STIMULUS MAY HOLD THE KEY. WHILE TRANSIENT (1-3 DAYS) PROTECTION AGAINST CNS ISCHEMIC INJURY IS WELL ESTABLISHED PRECLINICALLY FOLLOWING A SINGLE PRECONDITIONING STIMULUS, REPETITIVELY PRESENTING PRECONDITIONING STIMULI EXTENDS THE DURATION OF ISCHEMIC TOLERANCE BY MANY WEEKS. MOREOVER, REPETITIVE INTERMITTENT POSTCONDITIONING ENHANCES POST-ISCHEMIC RECOVERY METRICS AND IMPROVES LONG-TERM SURVIVAL. INTERMITTENT CONDITIONING IS ALSO EFFICACIOUS FOR PREVENTING OR DELAYING INJURY IN PRECLINICAL MODELS OF CHRONIC NEURODEGENERATIVE DISEASE, AND FOR PROMOTING LONG-LASTING FUNCTIONAL IMPROVEMENTS IN A NUMBER OF OTHER PATHOLOGIES AS WELL. ALTHOUGH THE DETAILED MECHANISMS UNDERLYING THESE PROTRACTED KINDS OF NEUROPLASTICITY REMAIN LARGELY UNSTUDIED, ACCUMULATING EMPIRICAL EVIDENCE SUPPORTS THE CONTENTION THAT ALL OF THESE ADAPTIVE PHENOTYPES ARE EPIGENETICALLY MEDIATED. GOING FORWARD, ADDITIONAL PRECLINICAL DEMONSTRATIONS OF THE ABILITY TO INDUCE SUSTAINED BENEFICIAL PHENOTYPES THAT REDUCE THE BURDEN OF ACUTE AND CHRONIC NEURODEGENERATION, AND EXPERIMENTAL INTERROGATIONS OF THE REGULATORY CONSTRUCTS RESPONSIBLE FOR THESE EPIGENETIC RESPONSES, WILL ACCELERATE THE IDENTIFICATION OF NOT ONLY EFFICACIOUS BUT ALSO PRACTICAL, ADAPTIVE EPIGENETICS-BASED TREATMENTS FOR INDIVIDUALS WITH NEUROLOGICAL DISEASE. 2015 13 4791 33 NUTRITIONAL CATCH-UP GROWTH. MALNUTRITION, MARKED BY VARIANT NUTRIENT DEFICIENCIES, IS CONSIDERED A LEADING CAUSE OF STUNTED GROWTH WORLDWIDE. IN DEVELOPING COUNTRIES, MALNUTRITION IS CAUSED MAINLY BY FOOD SHORTAGE AND INFECTIOUS DISEASES. MALNUTRITION MAY ALSO BE FOUND IN THE DEVELOPED WORLD, WHERE IT IS DUE MOSTLY TO PREMATURITY, CHRONIC DISEASES, AND ANOREXIA NERVOSA. IN MOST CASES, WHEN FOOD CONSUMPTION IS CORRECTED, SPONTANEOUS CATCH-UP (CU) GROWTH OCCURS. HOWEVER, CU GROWTH IS NOT ALWAYS COMPLETE, LEADING TO GROWTH DEFICITS. THEREFORE, IT IS IMPORTANT TO UNDERSTAND THE MECHANISMS THAT GOVERN THIS PROCESS. USING A RAT MODEL OF FOOD RESTRICTION FOLLOWED BY REFEEDING, WE ESTABLISHED A NUTRITION-INDUCED CU GROWTH MODEL. LEVELS OF LEPTIN AND INSULIN-LIKE GROWTH FACTOR-1 WERE FOUND TO SIGNIFICANTLY DECREASE WHEN FOOD WAS RESTRICTED AND TO INCREASE ALREADY 1 DAY AFTER REFEEDING. GENE EXPRESSION ANALYSIS OF THE GROWTH PLATE REVEALED THAT FOOD RESTRICTION SPECIFICALLY AFFECTS TRANSCRIPTION FACTORS SUCH AS THE HYPOXIA INDUCIBLE FACTOR-1 AND ITS DOWNSTREAM TARGETS ON THE ONE HAND, AND GLOBAL GENE EXPRESSION, INDICATING EPIGENETIC REGULATION, ON THE OTHER. FOOD RESTRICTION ALSO REDUCED THE LEVEL OF SEVERAL MICRORNAS, INCLUDING THE CHONDROCYTE-SPECIFIC MIR-140, WHICH LED TO AN INCREASE IN ITS TARGET, SIRT1, A CLASS III HISTONE DEACETYLASE. THESE FINDINGS MAY EXPLAIN THE GLOBAL CHANGES IN GENE EXPRESSION OBSERVED UNDER NUTRITIONAL MANIPULATION. WE SUGGEST THAT MULTIPLE LEVELS OF REGULATION, INCLUDING TRANSCRIPTION FACTORS, EPIGENETIC MECHANISMS, AND MICRORNAS RESPOND TO NUTRITIONAL CUES AND OFFER A POSSIBLE EXPLANATION FOR SOME OF THE EFFECTS OF FOOD RESTRICTION ON EPIPHYSEAL GROWTH PLATE GROWTH. THE MEANS WHEREBY THESE COMPONENTS SENSE CHANGES IN NUTRITIONAL STATUS ARE STILL UNKNOWN. DECIPHERING THE ROLE OF EPIGENETIC REGULATION IN GROWTH MAY PAVE THE WAY FOR THE DEVELOPMENT OF NEW TREATMENTS FOR CHILDREN WITH GROWTH DISORDERS. 2013 14 5439 31 RENAL CONSEQUENCES OF PRETERM BIRTH. BACKGROUND: THE DEVELOPMENTAL ORIGIN OF HEALTH AND DISEASE CONCEPT IDENTIFIES THE BRAIN, CARDIOVASCULAR, LIVER, AND KIDNEY SYSTEMS AS TARGETS OF FETAL ADVERSE PROGRAMMING WITH ADULT CONSEQUENCES. AS THE LIMITS OF VIABILITY IN PREMATURE INFANTS HAVE BEEN PUSHED TO LOWER GESTATIONAL AGES, THE LONG-TERM IMPACT OF PREMATURITY ON KIDNEYS STILL REMAINS A SIGNIFICANT BURDEN DURING HOSPITAL STAY AND BEYOND. OBJECTIVES: THE PURPOSE OF THIS STUDY IS TO SUMMARIZE AVAILABLE EVIDENCE, MECHANISMS, AND SHORT- AND LONG-TERM RENAL CONSEQUENCES OF PREMATURITY AND IDENTIFY NEPHROPROTECTIVE STRATEGIES AND AREAS OF UNCERTAINTY. RESULTS: KIDNEY SIZE AND NEPHRON NUMBER ARE KNOWN TO BE REDUCED IN SURVIVING PREMATURE INFANTS DUE TO DISRUPTION OF ORGANOGENESIS AT A CRUCIAL DEVELOPMENTAL TIME POINT. INFLAMMATION, HYPEROXIA, AND ANTIANGIOGENIC FACTORS PLAY A ROLE IN EPIGENETIC CONDITIONING WITH POTENTIAL LIFE-LONG CONSEQUENCES. ADDITIONAL KIDNEY INJURY FROM HYPOPERFUSION AND NEPHROTOXICITY RESULTS IN STRUCTURAL AND FUNCTIONAL CHANGES OVER TIME WHICH ARE OFTEN UNNOTICED. NEPHROPATHY OF PREMATURITY AND ACUTE KIDNEY INJURY CONFOUND GLOMERULAR AND TUBULAR MATURATION OF PRETERM KIDNEYS. KIDNEY PROTECTIVE STRATEGIES MAY AMELIORATE GROWTH FAILURE AND SUBOPTIMAL NEURODEVELOPMENTAL OUTCOMES IN THE SHORT TERM. IN LATER LIFE, SUBCLINICAL CHRONIC RENAL DISEASE MAY PROGRESS, EVEN IN ASYMPTOMATIC SURVIVORS. CONCLUSION: AWARENESS OF RENAL IMPLICATIONS OF THERAPEUTIC INTERVENTIONS AND RENAL CONSERVATION EFFORTS MAY LEAD TO A VARIETY OF SHORT AND LONG-TERM BENEFITS. ADEQUATE MONITORING AND SUPPLEMENTATION OF MICROELEMENT LOSSES, GATHERING IMPROVED DATA ON RENAL HANDLING, AND EXPLORATION OF NEW AVENUES SUCH AS RELIABLE MARKERS OF INJURY AND NEW THERAPEUTIC STRATEGIES IN CONTEMPORARY POPULATIONS, AS WELL AS LONG-TERM FOLLOW-UP OF RENAL FUNCTION, IS WARRANTED. 2017 15 1202 29 COULD DNA HYDROXYMETHYLATION BE CRUCIAL IN INFLUENCING STEROID HORMONE SIGNALING IN ENDOMETRIAL BIOLOGY AND ENDOMETRIOSIS? ENDOMETRIOSIS AFFECTS 10% OF REPRODUCTIVE-AGED WOMEN. IT IS CHARACTERIZED BY THE GROWTH OF THE ENDOMETRIUM, OUTSIDE THE UTERUS AND IS ASSOCIATED WITH INFERTILITY AND CHRONIC ABDOMINAL PAIN. LACK OF NONINVASIVE DIAGNOSTIC TOOLS AND EARLY SCREENING TESTS RESULTS IN DELAYED TREATMENT AND SUBSEQUENTLY INCREASED DISEASE SEVERITY. ENDOMETRIOSIS IS A DISEASE ASSOCIATED WITH A DEREGULATED HORMONAL RESPONSE, THEREFORE, UNDERSTANDING THE MOLECULAR MECHANISMS THAT GOVERN THIS HORMONAL INTERPLAY IS OF PARAMOUNT IMPORTANCE. DNA METHYLATION IS AN EPIGENETIC MARK THAT REGULATES GENE EXPRESSION AND IS OFTEN ASSOCIATED WITH GENES THAT CODE FOR STEROID RECEPTORS AND ENZYMES ASSOCIATED WITH ESTROGEN SYNTHESIS AND METABOLISM IN ENDOMETRIOSIS. DNA HYDROXYMETHYLATION, WHICH IS STRUCTURALLY SIMILAR TO METHYLATION BUT FUNCTIONALLY DIFFERENT, IS A BIOLOGICALLY CRITICAL MECHANISM THAT IS ALSO KNOWN TO REGULATE GENE EXPRESSION. TEN ELEVEN TRANSLOCATION (TET) PROTEINS MEDIATE HYDROXYMETHYLATION. HOWEVER, THE ROLE OF DNA HYDROXYMETHYLATION OR TETS IN THE ENDOMETRIUM REMAINS RELATIVELY UNEXPLORED. CURRENTLY, THE "GOLD STANDARD" TECHNIQUE USED TO STUDY METHYLATION PATTERNS IS BISULFITE GENOMIC SEQUENCING. THIS TECHNIQUE ALSO DETECTS HYDROXYMETHYLATION BUT FAILS TO DISTINGUISH BETWEEN THE TWO, THEREBY LIMITING OUR UNDERSTANDING OF THESE TWO PROCESSES. THE PRESENCE OF TETS IN THE MALE AND FEMALE REPRODUCTIVE TRACT AND ITS CONTRIBUTION TO ENDOMETRIAL CANCER MAKES IT AN IMPORTANT FACTOR TO STUDY IN ENDOMETRIOSIS. THIS REVIEW SUMMARIZES THE ROLE OF DNA METHYLATION IN ABERRANT STEROID HORMONE SIGNALING AND HYPOTHESIZES THAT HYDROXYMETHYLATION COULD BE A FACTOR INFLUENCING HORMONAL INSTABILITY SEEN IN ENDOMETRIOSIS. 2020 16 3904 33 LEPROSY PIRNOME: EXPLORING NEW POSSIBILITIES FOR AN OLD DISEASE. LEPROSY, WHICH IS CAUSED BY THE HUMAN PATHOGEN MYCOBACTERIUM LEPRAE, CAUSES NERVE DAMAGE, DEFORMITY AND DISABILITY IN OVER 200,000 PEOPLE EVERY YEAR. BECAUSE OF THE LONG DOUBLING TIME OF M. LEPRAE (13 DAYS) AND THE DELAYED ONSET OF DETECTABLE SYMPTOMS, WHICH IS ESTIMATED TO BE APPROXIMATELY 3-7 YEARS AFTER INFECTION, THERE IS ALWAYS A LARGE PERCENTAGE OF SUBCLINICALLY INFECTED INDIVIDUALS IN THE POPULATION WHO WILL EVENTUALLY DEVELOP THE DISEASE, MAINLY IN ENDEMIC COUNTRIES. PIRNAS COMPRISE THE LARGEST GROUP OF SMALL NONCODING RNAS FOUND IN HUMANS, AND THEY ARE DISTINCT FROM MICRORNAS (MIRNAS) AND SMALL INTERFERING RNAS (SIRNAS). PIRNAS FUNCTION IN TRANSPOSON SILENCING, EPIGENETIC REGULATION, AND GERMLINE DEVELOPMENT. THE FUNCTIONAL ROLE OF PIRNAS AND THEIR ASSOCIATED PIWI PROTEINS HAVE STARTED TO EMERGE IN THE DEVELOPMENT OF HUMAN CANCERS AND VIRAL INFECTIONS, BUT THEIR RELEVANCE TO BACTERIAL DISEASES HAS NOT BEEN INVESTIGATED. THE PRESENT STUDY REPORTS THE PIRNOME OF HUMAN SKIN, REVEALING THAT ALL BUT ONE OF THE PIRNAS EXAMINED ARE DOWNREGULATED IN LEPROSY SKIN LESIONS. CONSIDERING THAT ONE OF THE BEST CHARACTERIZED FUNCTIONS OF PIRNAS IN HUMANS IS POSTTRANSCRIPTIONAL MRNA SILENCING, THEIR FUNCTIONS ARE SIMILAR TO WHAT WE HAVE DESCRIBED FOR MIRNAS, INCLUDING ACTING ON APOPTOSIS, M. LEPRAE RECOGNITION AND ENGULFMENT, SCHWANN CELL (SC) DEMYELINATION, EPITHELIAL-MESENCHYMAL TRANSITION (EMT), LOSS OF SENSATION AND NEUROPATHIC PAIN. IN ADDITION TO NEW FINDINGS ON LEPROSY PHYSIOPATHOLOGY, THE DISCOVERY OF RELEVANT PIRNAS INVOLVED IN DISEASE PROCESSES IN HUMAN SKIN MAY PROVIDE NEW CLUES FOR THERAPEUTIC TARGETS, SPECIFICALLY TO CONTROL NERVE DAMAGE, A PROMINENT FEATURE OF LEPROSY THAT HAS NO CURRENTLY AVAILABLE PHARMACEUTICAL TREATMENT. 2020 17 5965 23 TEN-ELEVEN-TRANSLOCATION 2 (TET2) NEGATIVELY REGULATES HOMEOSTASIS AND DIFFERENTIATION OF HEMATOPOIETIC STEM CELLS IN MICE. THE TEN-ELEVEN-TRANSLOCATION 2 (TET2) GENE ENCODES A MEMBER OF TET FAMILY ENZYMES THAT ALTERS THE EPIGENETIC STATUS OF DNA BY OXIDIZING 5-METHYLCYTOSINE TO 5-HYDROXYMETHYLCYTOSINE (5HMC). SOMATIC LOSS-OF-FUNCTION MUTATIONS OF TET2 ARE FREQUENTLY OBSERVED IN PATIENTS WITH DIVERSE MYELOID MALIGNANCIES, INCLUDING MYELODYSPLASTIC SYNDROMES, MYELOPROLIFERATIVE NEOPLASMS, AND CHRONIC MYELOMONOCYTIC LEUKEMIA. BY ANALYZING MICE WITH TARGETED DISRUPTION OF THE TET2 CATALYTIC DOMAIN, WE SHOW HERE THAT TET2 IS A CRITICAL REGULATOR OF SELF-RENEWAL AND DIFFERENTIATION OF HEMATOPOIETIC STEM CELLS (HSCS). TET2 DEFICIENCY LED TO DECREASED GENOMIC LEVELS OF 5HMC AND AUGMENTED THE SIZE OF THE HEMATOPOIETIC STEM/PROGENITOR CELL POOL IN A CELL-AUTONOMOUS MANNER. IN COMPETITIVE TRANSPLANTATION ASSAYS, TET2-DEFICIENT HSCS WERE CAPABLE OF MULTILINEAGE RECONSTITUTION AND POSSESSED A COMPETITIVE ADVANTAGE OVER WILD-TYPE HSCS, RESULTING IN ENHANCED HEMATOPOIESIS INTO BOTH LYMPHOID AND MYELOID LINEAGES. IN VITRO, TET2 DEFICIENCY DELAYED HSC DIFFERENTIATION AND SKEWED DEVELOPMENT TOWARD THE MONOCYTE/MACROPHAGE LINEAGE. OUR DATA INDICATE THAT TET2 HAS A CRITICAL ROLE IN REGULATING THE EXPANSION AND FUNCTION OF HSCS, PRESUMABLY BY CONTROLLING 5HMC LEVELS AT GENES IMPORTANT FOR THE SELF-RENEWAL, PROLIFERATION, AND DIFFERENTIATION OF HSCS. 2011 18 4983 38 PATHOPHYSIOLOGY, CELLULAR AND MOLECULAR MECHANISMS OF FOETAL GROWTH RETARDATION. IN MAMMALS, SIZE AT BIRTH IS THE OUTCOME OF LENGTH OF GESTATION AND RATE OF FOETAL GROWTH. IN THE ABSENCE OF PREMATURE DELIVERY, FOETAL SIZE WITHIN SPECIES IS DETERMINED PRINCIPALLY BY FOETAL GROWTH RATE WHICH IS DEPENDENT ON BOTH GENETIC AND EPIGENETIC FACTORS. FAILURE OF EITHER OF THESE MECHANISMS LEADS TO FOETAL GROWTH RETARDATION. IN MAMMALS, INCLUDING HUMAN INFANTS, FOETAL GROWTH RETARDATION CAN OCCUR NATURALLY OR PATHOLOGICALLY. ONE MAJOR CAUSE FOR NATURAL FOETAL GROWTH RETARDATION OR RUNTING IS THE INCREASE IN LITTER SIZE. IN MANY CASES, HOWEVER, THE CAUSE OF RUNTING IS UNKNOWN. PARENTAL GENOTYPE OR ANTIGENIC DIFFERENCES BETWEEN THE MOTHER AND THE DEVELOPING CONCEPTUS MAY BE POTENTIAL CAUSES. PATHOLOGICAL FOETAL GROWTH RETARDATION OR INTRAUTERINE GROWTH RETARDATION (IUGR) IS DUE TO GENETIC CAUSES (CHROMOSOMAL ABNORMALITIES OR INHERITED SYNDROMES) OR EPIGENETIC CAUSES (INTRAUTERINE INFECTIONS, TOXINS AND CHEMICALS, MATERNAL DISEASES OF PREGNANCY AFFECTING THE PLACENTA). THE UNDERLYING PATHOPHYSIOLOGICAL PROCESSES THAT OCCUR AT THE CELLULAR AND MOLECULAR LEVEL IN IUGR ARE STILL UNKNOWN. REDUCTION IN THE SUPPLY OF SUBSTRATES THAT ARE NECESSARY FOR NORMAL CELLULAR FUNCTION, AND ALTERATION IN MEDIATOR MOLECULES THAT REGULATE CELLULAR GROWTH AND DIFFERENTIATION, ARE IMPORTANT MECHANISMS. A DECREASE IN GROWTH PROMOTING FACTORS OR AN INCREASE IN GROWTH INHIBITORY FACTORS MAY LEAD TO GROWTH FAILURE. GROWTH FACTORS AND THEIR RECEPTORS ARE EXPRESSED IN THE DEVELOPING EMBRYO (AS EARLY AS THE 1-2-CELL STAGE), PLACENTA AND MATERNAL UTERINE TISSUES, SUGGESTING THAT THESE MOLECULES MAY PLAY A ROLE IN REGULATING NORMAL GROWTH AND DIFFERENTIATION OF THE CONCEPTUS AS WELL AS MATERNAL REPRODUCTIVE TISSUES. THE LOCAL EXPRESSION WITHIN DEVELOPING TISSUES INDICATES THAT THESE FACTORS ACT IN EITHER AUTOCRINE OR PARACRINE MECHANISM. RECENT STUDIES USING GENE TARGETING TO KNOCK OUT ONE ALLELE OF INSULIN-LIKE GROWTH FACTOR II (IGF II) GENE IN MICE WHICH RESULTED IN GROWTH RETARDED PUPS AT BIRTH, STRONGLY SUPPORT THE IMPORTANCE OF LOCAL IGF II IN REGULATING TISSUE GROWTH. FOETAL GROWTH RETARDATION HAS ALSO BEEN INDUCED EXPERIMENTALLY IN SEVERAL SPECIES USING ONE OF THE FOLLOWING METHODS: (I) MATERNAL UNDERNUTRITION, (II) CHRONIC HYPOXIA, (III) PROLONGED REDUCTION IN UTERINE BLOOD FLOW, (IV) REDUCTION IN PLACENTAL SIZE, AND (V) ENDOCRINE ALTERATIONS. THESE MODELS PROVIDE USEFUL INFORMATION ON THE PHYSIOLOGICAL MECHANISMS UNDERLYING A SPECIFIC TYPE OF GROWTH RETARDATION. THESE IN-VIVO MODELS AND IN-VIVO TISSUE CULTURE MODELS CAN NOW BE ANALYSED BY BIOCHEMICAL AND MOLECULAR BIOLOGICAL TECHNIQUES TO UNRAVEL THE BASIC MECHANISMS THAT UNDERLIE FOETAL GROWTH RETARDATION. 1993 19 1888 22 ENDOMETRIOSIS AND IN VITRO FERTILISATION. THE AIM OF THE PRESENT REVIEW WAS TO DISCUSS A MATTER OF CONCERN IN THE CLINICAL FIELD OF OBSTETRICS/GYNECOLOGY, NAMELY THE POTENCY OF IN VITRO FERTILIZATION (IVF) IN THE MANAGEMENT OF ENDOMETRIOSIS-ASSOCIATED INFERTILITY. ENDOMETRIOSIS IS A MEDICAL CONDITION AFFECTING ONE TENTH OF WOMEN IN THEIR FERTILE YEARS, AND ACCOUNTS FOR UP TO 50% OF INFERTILE WOMEN. THUS, SUCH HIGH PREVALENCE HAS ESTABLISHED THE NECESSITY FOR INVESTIGATING THE EFFECTIVENESS OF AVAILABLE TECHNIQUES IN ERADICATING THE DISEASE AND CONSTRAINING INFERTILITY AS WELL AS THE ACCOMPANYING PAIN SYMPTOMS OF ENDOMETRIOSIS. THE UNDERLYING MECHANISMS CONNECTING ENDOMETRIOSIS WITH LOW FECUNDITY HAVE BEEN EXTENSIVELY STUDIED, BOTH IN TERMS OF GENETIC ALTERATIONS AND EPIGENETIC EVENTS THAT CONTRIBUTE TO THE MANIFESTATION OF AN INFERTILITY PHENOTYPE IN WOMEN WITH THE DISEASE. SEVERAL STUDIES HAVE DEALT WITH THE IMPACT OF IVF IN PREGNANCY RATES (PRS) ON PATIENTS WITH ENDOMETRIOSIS, PARTICULARLY REGARDING WOMEN WHO WISH TO CONCEIVE. RESULTS RETRIEVED FROM STUDIES AND META-ANALYSES DEPICT A DIVERSE PATTERN OF IVF SUCCESS, UNDERLINING THE INVOLVEMENT OF INDIVIDUAL PARAMETERS IN THE CONFIGURATION OF THE FINAL OUTCOME. THE ULTIMATE DECISION ON UNDERGOING IVF TREATMENT SHOULD BE BASED ON OBJECTIVE CRITERIA AND CLINICIANS' EXPERIENCE, CUSTOMIZED ACCORDING TO PATIENTS' INDIVIDUAL NEEDS. 2018 20 837 41 CHEMICALLY INDUCED RENAL TUBULE TUMORS IN THE LABORATORY RAT AND MOUSE: REVIEW OF THE NCI/NTP DATABASE AND CATEGORIZATION OF RENAL CARCINOGENS BASED ON MECHANISTIC INFORMATION. THE INCIDENCE OF RENAL TUBULE CARCINOGENESIS IN MALE AND FEMALE RATS OR MICE WITH 69 CHEMICALS FROM THE 513 BIOASSAYS CONDUCTED TO DATE BY THE NCI/NTP HAS BEEN COLLATED, THE CHEMICALS CATEGORIZED, AND THE RELATIONSHIP BETWEEN CARCINOGENESIS AND RENAL TUBULE HYPERPLASIA AND EXACERBATION OF THE SPONTANEOUS, AGE-RELATED RODENT DISEASE CHRONIC PROGRESSIVE NEPHROPATHY (CPN) EXAMINED. WHERE INFORMATION ON MECHANISM OR MODE OF ACTION EXISTS, THE CHEMICALS HAVE BEEN CATEGORIZED BASED ON THEIR ABILITY TO DIRECTLY OR INDIRECTLY INTERACT WITH RENAL DNA, OR ON THEIR ACTIVITY VIA EPIGENETIC PATHWAYS INVOLVING EITHER DIRECT OR INDIRECT CYTOTOXICITY WITH REGENERATIVE HYPERPLASIA, OR EXACERBATION OF CPN. NINE CHEMICALS WERE IDENTIFIED AS DIRECTLY INTERACTING WITH DNA, WITH SIX OF THESE PRODUCING RENAL TUBULE TUMORS AT HIGH INCIDENCE IN RATS OF BOTH SEXES, AND IN SOME CASES ALSO IN MICE. OCHRATOXIN A WAS THE MOST POTENT COMPOUND IN THIS GROUP, PRODUCING A HIGH TUMOR INCIDENCE AT VERY LOW DOSES, OFTEN WITH METASTASIS. THREE CHEMICALS WERE DISCUSSED IN THE CONTEXT OF INDIRECT DNA DAMAGE MEDIATED BY AN OXIDATIVE FREE RADICAL MECHANISM, ONE OF THESE BEING FROM THE NTP DATABASE. A THIRD CATEGORY INCLUDED FOUR CHEMICALS THAT HAD THE POTENTIAL TO CAUSE DNA DAMAGE FOLLOWING CONJUGATION WITH GLUTATHIONE AND SUBSEQUENT ENZYMATIC ACTIVATION TO A REACTIVE SPECIES, USUALLY A THIOL-CONTAINING ENTITY. TWO CHEMICALS WERE ALLOCATED INTO THE CATEGORY INVOLVING A DIRECT CYTOTOXIC ACTION ON THE RENAL TUBULE FOLLOWED BY SUSTAINED COMPENSATORY CELL PROLIFERATION, WHILE NINE WERE INCLUDED IN A GROUP WHERE THE CELL LOSS AND SUSTAINED INCREASE IN RENAL TUBULE CELL TURNOVER WERE DEPENDENT ON LYSOSOMAL ACCUMULATION OF THE MALE RAT-SPECIFIC PROTEIN, ALPHA2MU-GLOBULIN. IN A SIXTH CATEGORY, MORPHOLOGIC EVIDENCE ON TWO CHEMICALS INDICATED THAT THE RENAL TUMORS WERE A CONSEQUENCE OF EXACERBATED CPN. FOR THE REMAINING CHEMICALS, THERE WERE NO PERTINENT DATA ENABLING ASSIGNMENT TO A MECHANISTIC CATEGORY. ACCORDINGLY, THESE CHEMICALS, ACTING THROUGH AN AS YET UNKNOWN MECHANISM, WERE GROUPED AS EITHER BEING ASSOCIATED WITH AN ENHANCEMENT OF CPN (CATEGORY 7, 16 CHEMICALS), OR NOT ASSOCIATED WITH ENHANCED CPN (CATEGORY 8, 4 CHEMICALS). A NINTH CATEGORY DEALT WITH 11 CHEMICALS THAT WERE REGARDED AS PRODUCING INCREASES IN RENAL TUBULE TUMORS THAT DID NOT REACH STATISTICAL SIGNIFICANCE. A 10TH CATEGORY DISCUSSED 6 CHEMICALS THAT INDUCED RENAL TUMORS IN MICE BUT NOT IN RATS, PLUS 8 CHEMICALS THAT PRODUCED A LOW INCIDENCE OF RENAL TUBULE TUMORS IN MICE THAT DID NOT REACH STATISTICAL SIGNIFICANCE. AS MORE MECHANISTIC DATA ARE GENERATED, SOME CHEMICALS WILL INEVITABLY BE PLACED IN DIFFERENT GROUPS, PARTICULARLY THOSE FROM CATEGORIES 7 AND 8. A LARGE NUMBER OF CHEMICALS IN THE SERIES EXACERBATED CPN, BUT THOSE IN CATEGORY 7 ESPECIALLY MAY BE CANDIDATES FOR INCLUSION IN CATEGORY 6 WHEN FURTHER INFORMATION IS GLEANED FROM THE RELEVANT NTP STUDIES. ALSO, NEW DATA ON SPECIFIC CHEMICALS WILL PROBABLY EXPAND CATEGORY 5 AS CYTOTOXICITY AND CELL REGENERATION ARE IDENTIFIED AS OBLIGATORY STEPS IN RENAL CARCINOGENESIS IN MORE CASES. ADDITIONAL CONFIRMATORY OUTCOMES ARISING FROM THIS REVIEW ARE THAT METASTASES FROM RENAL TUBULE TUMORS, WHILE ENCOUNTERED WITH CHEMICALS CAUSING DNA DAMAGE, ARE RARE WITH THOSE ACTING THROUGH AN EPIGENETIC PATHWAY, WITH THE EXCEPTION BEING FUMONISIN B1; THAT MALE RATS AND MICE ARE GENERALLY MORE SUSCEPTIBLE THAN FEMALE RATS AND MICE TO CHEMICAL INDUCTION OF RENAL TUBULE TUMORS; AND THAT A BACKGROUND OF ATYPICAL TUBULE HYPERPLASIA IS A USEFUL INDICATOR REFLECTING A CHEMICALLY ASSOCIATED RENAL TUBULE TUMOR RESPONSE. WITH RESPECT TO RENAL TUBULE TUMORS AND HUMAN RISK ASSESSMENT, CHEMICALS IN CATEGORIES 1 AND 2, AND POSSIBLY 3, WOULD CURRENTLY BE JUDGED BY LINEAR DEFAULT METHODS; CHEMICALS IN CATEGORY 4 (AND PROBABLY SOME IN CATEGORY 3) AS EXHIBITING A THRESHOLD OF ACTIVITY WARRANTING THE BENCHMARK APPROACH; AND THOSE IN CATEGORIES 5 AND 6 AS REPRESENTING MECHANISMS THAT HAVE NO RELEVANCE FOR EXTRAPOLATION TO HUMANS. 2004