1 3129 134 GIVINOSTAT: AN EMERGING TREATMENT FOR POLYCYTHEMIA VERA. INTRODUCTION: POLYCYTHEMIA VERA (PV), A PHILADELPHIA CHROMOSOME-NEGATIVE MYELOPROLIFERATIVE NEOPLASM, IS CHARACTERIZED BY PANMYELOSIS, PANCYTOSIS, AND A JAK2 MUTATION. PATIENTS ARE AT INCREASED RISK OF THROMBOHEMORRHAGIC EVENTS, AND PROGRESSION TO MYELOFIBROSIS OR ACUTE LEUKEMIA. CURRENT TREATMENTS INCLUDE ASPIRIN, PHLEBOTOMY, AND CYTOREDUCTIVE DRUGS (MOST COMMONLY HYDROXYUREA). GIVINOSTAT IS A POTENT, CLASS I/II HISTONE DEACETYLASE (HDAC) INHIBITOR THAT IS IN PHASE I/II CLINICAL TRIALS IN PV. GIVINOSTAT WAS WELL TOLERATED AND YIELDED PROMISING CLINICO-HEMATOLOGICAL RESPONSES. A PHASE III STUDY OF GIVINOSTAT VERSUS HYDROXYUREA IN HIGH-RISK PV PATIENTS IS PLANNED. AREAS COVERED: WE PRESENT AN OVERVIEW OF PV, CURRENT TREATMENT GUIDELINES, AND THE PUTATIVE MECHANISM(S) OF ACTION OF GIVINOSTAT. WE DISCUSS THE PRECLINICAL AND CLINICAL STUDIES OF GIVINOSTAT IN PV AND BRIEFLY REVIEW APPROVED AND INVESTIGATIONAL COMPETITOR COMPOUNDS. EXPERT OPINION: HDAC INHIBITORS HAVE LONG BEEN KNOWN TO BE ACTIVE IN PV, BUT CHRONIC TOXICITIES CAN BE CHALLENGING. GIVINOSTAT, HOWEVER, IS ACTIVE AND WELL TOLERATED, AND IS ENTERING A PIVOTAL PHASE III RANDOMIZED TRIAL. GIVINOSTAT OFFERS THE POSSIBILITY OF REPLACING HYDROXYUREA AS THE STANDARD FIRST-LINE CYTOREDUCTIVE CHOICE FOR PV PATIENTS. THIS WOULD COMPLETELY CHANGE THE CURRENT THERAPEUTIC PARADIGM AND GUIDELINES FOR PV MANAGEMENT. ALTHOUGH SURROGATE CLINICAL STUDY ENDPOINTS MAY SUFFICE FOR REGULATORY PURPOSES, THROMBOSIS REDUCTION AND PREVENTION OF DISEASE PROGRESSION REMAIN MOST IMPORTANT TO PATIENTS AND CLINICIANS. 2020 2 5799 42 STEPPING OUT OF ANTIQUITY: AN UPDATE ON EMERGING DRUGS FOR THE TREATMENT OF POLYCYTHEMIA VERA. INTRODUCTION: POLYCYTHEMIA VERA IS A CHRONIC HEMATOLOGIC MALIGNANCY FREQUENTLY PRESENTED WITH CONSTITUTIONAL SYMPTOMS AND ASSOCIATED WITH AN INCREASED RISK OF THROMBOSIS, HEMORRHAGE, AND PROGRESSION TO MYELOFIBROSIS OR ACUTE MYELOID LEUKEMIA. CURRENT TREATMENT STRATEGIES REDUCE THROMBOHEMORRHAGIC RISK BY CONTROLLING BLOOD COUNTS AND INHIBITING PLATELETS, BUT OFTEN FAIL TO ADDRESS DISEASE-RELATED SYMPTOMS OR BIOLOGICALLY MODIFY THE DISEASE.AREAS COVERED: WE REVIEW THE CURRENT PARADIGM FOR TREATING POLYCYTHEMIA VERA, HIGHLIGHT AREAS OF UNMET NEED, REVIEW THERAPEUTIC AGENTS IN LATE STAGE CLINICAL DEVELOPMENT, AND PROVIDE AN OVERARCHING VIEW OF HOW THESE EMERGING AGENT MAY FIT INTO THE FUTURE ARMAMENTARIUM OF POLYCYTHEMIA VERA TREATMENTS.EXPERT OPINION: THE SHIFT FROM FOCUSING SOLELY ON SECONDARY PREVENTION OF THROMBOHEMORRHAGIC EVENTS TO A COMPREHENSIVE TREATMENT STRATEGY THAT ADDITIONALLY AIMS TO IMPROVE QUALITY OF LIFE AND PREVENT DISEASE PROGRESSION HAS RESULTED IN A RAPIDLY EVOLVING THERAPEUTIC LANDSCAPE THAT PROMISES TO MOVE THE TREATMENT OF POLYCYTHEMIA VERA OUT OF ANTIQUITY INTO THE MODERN AGE. 2021 3 5257 43 PROGRESSION OF MYELOPROLIFERATIVE NEOPLASMS (MPN): DIAGNOSTIC AND THERAPEUTIC PERSPECTIVES. CLASSICAL BCR-ABL-NEGATIVE MYELOPROLIFERATIVE NEOPLASMS (MPN) ARE A HETEROGENEOUS GROUP OF HEMATOLOGIC MALIGNANCIES, INCLUDING ESSENTIAL THROMBOCYTHEMIA (ET), POLYCYTHEMIA VERA (PV), AND PRIMARY MYELOFIBROSIS (PMF), AS WELL AS POST-PV-MF AND POST-ET-MF. PROGRESSION TO MORE SYMPTOMATIC DISEASE, SUCH AS OVERT MF OR ACUTE LEUKEMIA, REPRESENTS ONE OF THE MAJOR CAUSES OF MORBIDITY AND MORTALITY. THERE ARE CLINICALLY EVIDENT BUT ALSO SUBCLINICAL TYPES OF MPN PROGRESSION. CLINICALLY EVIDENT PROGRESSION INCLUDES EVOLUTION FROM ET TO PV, ET TO POST-ET-MF, PV TO POST-PV-MF, OR PRE-PMF TO OVERT PMF, AND TRANSFORMATION OF ANY OF THESE SUBTYPES TO MYELODYSPLASTIC NEOPLASMS OR ACUTE LEUKEMIA. THROMBOSIS, MAJOR HEMORRHAGE, SEVERE INFECTIONS, OR INCREASING SYMPTOM BURDEN (E.G., PRURITUS, NIGHT SWEATS) MAY HERALD PROGRESSION. SUBCLINICAL TYPES OF PROGRESSION MAY INCLUDE INCREASES IN THE EXTENT OF BONE MARROW FIBROSIS, INCREASES OF DRIVER GENE MUTATIONAL ALLELE BURDEN, AND CLONAL EVOLUTION. THE UNDERLYING CAUSES OF MPN PROGRESSION ARE DIVERSE AND CAN BE ATTRIBUTED TO GENETIC ALTERATIONS AND CHRONIC INFLAMMATION. PARTICULARLY, BYSTANDER MUTATIONS IN GENES ENCODING EPIGENETIC REGULATORS OR SPLICING FACTORS WERE ASSOCIATED WITH PROGRESSION. FINALLY, COMORBIDITIES SUCH AS SYSTEMIC INFLAMMATION, CARDIOVASCULAR DISEASES, AND ORGAN FIBROSIS MAY AUGMENT THE RISK OF PROGRESSION. THE AIM OF THIS REVIEW WAS TO DISCUSS TYPES AND MECHANISMS OF MPN PROGRESSION AND HOW THEIR KNOWLEDGE MIGHT IMPROVE RISK STRATIFICATION AND THERAPEUTIC INTERVENTION. IN VIEW OF THESE ASPECTS, WE DISCUSS THE POTENTIAL BENEFITS OF EARLY DIAGNOSIS USING MOLECULAR AND FUNCTIONAL IMAGING AND EXPLOITABLE THERAPEUTIC STRATEGIES THAT MAY PREVENT PROGRESSION, BUT ALSO HIGHLIGHT CURRENT CHALLENGES AND METHODOLOGICAL PITFALLS. 2021 4 6856 34 [NOT AVAILABLE]. BIOLOGICAL ASPECTS OF JAK/STAT SIGNALING IN BCR-ABL-NEGATIVE MYELOPROLIFERATIVE NEOPLASMS: MYELOPROLIFERATIVE DISORDERS MORE RECENTLY NAMED MYELOPROLIFERATIVE NEOPLASMS (MPN) DISPLAY SEVERAL CLINICAL ENTITIES: CHRONIC MYELOID LEUKEMIA (CML), THE CLASSICAL MPN INCLUDING POLYCYTHEMIA VERA (PV), ESSENTIAL THROMBOCYTHEMIA (ET), PRIMARY MYELOFIBROSIS (PMF) AND ATYPICAL AND UNCLASSIFIABLE NMP. THE TERM MPN IS MOSTLY USED FOR CLASSICAL BCR-ABL-NEGATIVE (MYELOPROLIFERATIVE DISORDER) (ET, PV, PMF). THESE ARE CLONAL DISEASES RESULTING FROM THE TRANSFORMATION OF AN HEMATOPOIETIC STEM CELL AND LEADING TO AN ABNORMAL PRODUCTION OF MYELOID CELLS. THE GENETIC DEFECTS RESPONSIBLE FOR THE MYELOPROLIFERATIVE ABNORMALITIES ARE CALLED << DRIVER >> MUTATIONS AND ALL RESULT IN DEREGULATION OF THE CYTOKINE RECEPTOR / JAK2 / STAT AXIS. AMONG THEM, JAK2, THE THROMBOPOIETIN RECEPTOR (MPL) AND CALRETICULIN (CALR) MUTATIONS ARE FOUND IN AROUND 90% OF THE CASES. THESE DRIVER MPN MUTATIONS CAN BE ASSOCIATED WITH OTHER DRIVER MUTATIONS ALSO FOUND IN OTHER HEMATOLOGICAL MALIGNANCIES, ESPECIALLY IN PMFS. THESE ARE CHRONIC DISEASES WITH MAJOR RISKS BEING THROMBOSIS, HEMORRHAGE AND CYTOPENIAS FOR PMF AND THE LONG-TERM PROGRESSION TO MYELOFIBROSIS AND THE TRANSFORMATION TO LEUKEMIA. MOST RECENT THERAPEUTIC HAVE FOCUSED ON TARGETING THE JAK2 SIGNALING PATHWAY DIRECTLY BY INHIBITORS OF JAK2 OR INDIRECTLY. INTERFERON A ALLOWS IN SOME CASES HEMATOLOGIC AND MOLECULAR REMISSION PATIENTS. 2016 5 1076 30 CLONAL HEMATOPOIESIS IN MYELOPROLIFERATIVE NEOPLASMS CONFERS A PREDISPOSITION TO BOTH THROMBOSIS AND CANCER. PURPOSE OF REVIEW: THIS REVIEW FOCUSES ON VASCULAR COMPLICATIONS ASSOCIATED WITH CHRONIC MYELOPROLIFERATIVE NEOPLASMS (MPN) AND MORE SPECIFICALLY AIMS TO DISCUSS THE CLINICAL AND BIOLOGICAL EVIDENCE SUPPORTING THE EXISTENCE OF A LINK BETWEEN CLONAL HEMATOPOIESIS, CARDIOVASCULAR EVENTS (CVE), AND SOLID CANCER (SC). RECENT FINDINGS: THE MPN NATURAL HISTORY IS DRIVEN BY UNCONTROLLED CLONAL MYELOPROLIFERATION SUSTAINED BY ACQUIRED SOMATIC MUTATIONS IN DRIVER (JAK2, CALR, AND MPL) AND NON-DRIVER GENES, INVOLVING EPIGENETIC (E.G., TET2, DNMT3A) REGULATORS, CHROMATIN REGULATOR GENES (E.G., ASXL1, EZH2), AND SPLICING MACHINERY GENES (E.G., SF3B1). THE GENOMIC ALTERATIONS AND ADDITIONAL THROMBOSIS ACQUIRED RISK FACTORS ARE DETERMINANTS FOR CVE. THERE IS EVIDENCE THAT CLONAL HEMATOPOIESIS CAN ELICIT A CHRONIC AND SYSTEMIC INFLAMMATION STATUS THAT ACTS AS DRIVING FORCE FOR THE DEVELOPMENT OF THROMBOSIS, MPN EVOLUTION, AND SECOND CANCER (SC). THIS NOTION MAY EXPLAIN THE MECHANISM THAT LINKS ARTERIAL THROMBOSIS IN MPN PATIENTS AND SUBSEQUENT SOLID TUMORS. IN THE LAST DECADE, CLONAL HEMATOPOIESIS OF INDETERMINATE POTENTIAL (CHIP) HAS BEEN DETECTED IN THE GENERAL POPULATION PARTICULARLY IN THE ELDERLY AND INITIALLY FOUND IN MYOCARDIAL INFARCTION AND STROKE, RISING THE HYPOTHESIS THAT THE INFLAMMATORY STATUS CHIP-ASSOCIATED COULD CONFER PREDISPOSITION TO BOTH CARDIOVASCULAR DISEASES AND CANCER. IN SUMMARY, CLONAL HEMATOPOIESIS IN MPN AND CHIP CONFER A PREDISPOSITION TO CARDIOVASCULAR EVENTS AND CANCER THROUGH CHRONIC AND SYSTEMIC INFLAMMATION. THIS ACQUISITION COULD OPEN NEW AVENUES FOR ANTITHROMBOTIC THERAPY BOTH IN MPNS AND IN GENERAL POPULATION BY TARGETING BOTH CLONAL HEMATOPOIESIS AND INFLAMMATION. 2023 6 373 29 AN EMERGING ROLE OF NEUTROPHILS AND NETOSIS IN CHRONIC INFLAMMATION AND FIBROSIS IN SYSTEMIC LUPUS ERYTHEMATOSUS (SLE) AND ANCA-ASSOCIATED VASCULITIDES (AAV): IMPLICATIONS FOR THE PATHOGENESIS AND TREATMENT. NEUTROPHILS DERIVE FROM HEMATOPOIETIC STEM CELLS (HSCS) WITH SYSTEMIC INFLAMMATION DRIVING THEIR ACTIVATION AND DIFFERENTIATION TO MYELOID PROGENITORS TO ENSURE ENHANCED MYELOPOIESIS. EPIGENETIC REPROGRAMING AND RE-EDUCATION OF THESE HSCS PRODUCES NEUTROPHILS PRIMED TOWARDS ELIMINATION OF PATHOGENS AND INCREASED INFLAMMATORY RESPONSE. NEUTROPHILS -AN IMPORTANT COMPONENT OF ACUTE INFLAMMATION- ARE NOT PRESENT IN CHRONIC INFLAMMATORY TISSUES LEADING TO THE FALSE ASSUMPTION THAT THEY MAY NOT BE AS IMPORTANT FOR THE LATTER. ACTIVATED NEUTROPHILS MAY RELEASE NEUTROPHIL EXTRACELLULAR TRAPS (NETS) DURING A DISTINCT FORM OF CELL DEATH, NAMED NETOSIS; NETS ARE RICH IN BIOACTIVE MOLECULES THAT PROMOTE THROMBOSIS (INCLUDING ATHEROTHROMBOSIS), INFLAMMATION AND FIBROSIS. THUS, ALTHOUGH NEUTROPHILS MAY NOT BE PRESENT IN CHRONIC INFLAMMATORY LESIONS, THEIR REMNANTS MAY AMPLIFY THE INFLAMMATORY RESPONSE BEYOND THEIR SHORT LIFE-SPAN IN THE TISSUES. HEREIN, WE REVIEW CURRENT EVIDENCE SUPPORTING A ROLE OF NEUTROPHILS AND NETOSIS IN TISSUE INJURY AND DYSFUNCTION IN SYSTEMIC AUTOIMMUNITY USING AS DISEASE PARADIGMS SYSTEMIC LUPUS ERYTHEMATOSUS (SLE) AND THE ANCA-ASSOCIATED VASCULITIDES (AAV). WE ALSO DISCUSS THE MECHANISMS INVOLVED AND THEIR POTENTIAL AS TARGETS FOR NOVEL THERAPY AND DRUG REPOSITIONING. 2019 7 361 33 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 8 4151 27 MECHANISTIC INSIGHTS INTO GLUCOSE INDUCED VASCULAR EPIGENETIC REPROGRAMMING IN TYPE 2 DIABETES. ENDOTHELIAL CELLS LINING THE VESSEL WALL REGULATE THROMBOSIS, INFLAMMATION, ANGIOGENESIS AND BALANCE BETWEEN VASOCONSTRICTION AND VASODILATORY FUNCTIONS. SUBJECTS WITH TYPE 2 DIABETES (T2D) ACCRUE A MULTITUDE OF VASCULOPATHIES CAUSING HIGH MORBIDITY AND MORTALITY ACROSS THE GLOBE. HIGH GLUCOSE AND ITS MODIFIED PRODUCTS SUCH AS ADVANCED GLYCATION END PRODUCTS LEAD TO A BIDIRECTIONAL ACTIVATION OF INFLAMMATORY AND EPIGENETIC MACHINERY IN ENDOTHELIAL CELLS RESULTING IN A STATE OF CHRONIC INFLAMMATORY MILIEU AND EVENTUALLY INTO VASCULAR COMPLICATIONS. CLINICAL AND EXPERIMENTAL STUDIES HAVE SHOWN THAT DESPITE THE THERAPEUTIC NORMALIZATION OF GLUCOSE LEVELS, SUBJECTS WITH T2D OVERT TO VASCULAR COMPLICATIONS THROUGH A PROCESS OF METABOLIC MEMORY WHICH IS ASSOCIATED WITH SIGNIFICANT EPIGENETIC REPROGRAMMING IN ENDOTHELIAL CELLS. IN NORMAL PHYSIOLOGICAL CONDITIONS, VASCULAR ENDOTHELIAL CELLS DISPLAY A QUIESCENT STATE AND ONLY IN RESPONSE TO EITHER PHYSIOLOGICAL OR PATHOLOGICAL RESPONSE, ENDOTHELIAL CELLS UNDERGO PROLIFERATION. DURING THE PATHOGENESIS OF T2D, DNA METHYLATION, HISTONE MARKS AND NON-CODING RNAS FORMING THE EPIGENETIC LANDSCAPE ARE DYSREGULATED AND ACTIVATE QUIESCENT ENDOTHELIAL CELLS TO SWITCH ON A DIVERSE SET OF MOLECULAR ACTIVITIES AND LEAD TO ENDOTHELIAL DYSFUNCTION. IN THE PRESENT REVIEW, WE PROVIDE A COMPREHENSIVE OVERVIEW OF HOW HYPERGLYCEMIA IN T2D REPROGRAMS ENDOTHELIAL EPIGENOME AND LEAD TO FUNCTIONAL CONSEQUENCES IN THE PATHOGENESIS OF VASCULAR COMPLICATIONS. FURTHER, WE CATALOGUE AND DISCUSS EPI-DRUGS THAT MAY AMELIORATE ENDOTHELIAL FUNCTIONS DURING T2D. 2022 9 2378 27 EPIGENETIC REGULATION OF VASCULAR SMOOTH MUSCLE CELL PHENOTYPE SWITCHING IN ATHEROSCLEROTIC ARTERY REMODELING: A MINI-REVIEW. ATHEROSCLEROSIS IS A CHRONIC INFLAMMATORY DISEASE CHARACTERIZED BY EXTENSIVE REMODELING OF MEDIUM AND LARGE-SIZED ARTERIES. INWARD REMODELING (=LUMEN SHRINKAGE) OF THE VASCULAR WALLS IS THE UNDERLYING CAUSE FOR ISCHEMIA IN TARGET ORGANS. THEREFORE, INWARD REMODELING CAN BE CONSIDERED THE PREDOMINANT FEATURE OF ATHEROSCLEROTIC PATHOLOGY. OUTWARD REMODELING (=LUMEN ENLARGEMENT) IS A PHYSIOLOGICAL RESPONSE COMPENSATING FOR LUMEN SHRINKAGE CAUSED BY NEOINTIMAL HYPERPLASIA, BUT AS A PATHOLOGICAL RESPONSE TO CHANGES IN BLOOD FLOW, OUTWARD REMODELING LEADS TO SUBSTANTIAL ARTERIAL WALL THINNING. THINNED VASCULAR WALLS ARE PRONE TO RUPTURE, AND SUBSEQUENT THROMBUS FORMATION ACCOUNTS FOR THE MAJORITY OF ACUTE CARDIOVASCULAR EVENTS. PATHOLOGICAL REMODELING IS DRIVEN BY INFLAMMATORY CELLS WHICH INDUCE VASCULAR SMOOTH MUSCLE CELLS TO SWITCH FROM QUIESCENT TO A PROLIFERATIVE AND MIGRATORY PHENOTYPE. AFTER DECADES OF INTENSIVE RESEARCH, THE MOLECULAR MECHANISMS OF ARTERIAL REMODELING ARE STARTING TO UNFOLD. IN THIS MINI-REVIEW, WE SUMMARIZE THE CURRENT KNOWLEDGE OF THE EPIGENETIC AND TRANSCRIPTIONAL REGULATION OF VASCULAR SMOOTH MUSCLE CELL PHENOTYPE SWITCHING FROM THE CONTRACTILE TO THE SYNTHETIC PHENOTYPE INVOLVED IN ARTERIAL REMODELING AND DISCUSS POTENTIAL THERAPEUTIC OPTIONS. 2021 10 2687 33 EVIDENCE OF EPIGENETIC ALTERATIONS IN THROMBOSIS AND COAGULATION: A SYSTEMATIC REVIEW. THROMBOSIS IN THE CONTEXT OF CARDIOVASCULAR DISEASE (CVD) AFFECTS MAINLY THE BLOOD VESSELS SUPPLYING THE HEART, BRAIN AND PERIPHERIES AND IT IS THE LEADING CAUSE OF DEATH WORLDWIDE. THE PATHOPHYSIOLOGICAL THROMBOTIC MECHANISMS ARE LARGELY UNKNOWN. HERITABILITY CONTRIBUTES TO A 30% OF THE INCIDENCE OF CVD. THE REMAINING VARIATION CAN BE EXPLAINED BY LIFE STYLE FACTORS SUCH AS SMOKING, DIETARY AND EXERCISE HABITS, ENVIRONMENTAL EXPOSURE TO TOXINS, AND DRUG USAGE AND OTHER COMORBIDITIES. EPIGENETIC VARIATION CAN BE ACQUIRED OR INHERITED AND CONSTITUTES AN INTERACTION BETWEEN GENES AND THE ENVIRONMENT. EPIGENETICS HAVE BEEN IMPLICATED IN ATHEROSCLEROSIS, ISCHEMIA/REPERFUSION DAMAGE AND THE CARDIOVASCULAR RESPONSE TO HYPOXIA. EPIGENETIC REGULATORS OF GENE EXPRESSION ARE MAINLY THE METHYLATION OF CPG ISLANDS, HISTONE POST TRANSLATIONAL MODIFICATIONS (PTMS) AND MICRORNAS (MIRNAS). THESE EPIGENETIC REGULATORS CONTROL GENE EXPRESSION EITHER THROUGH ACTIVATION OR SILENCING. EPIGENETIC CONTROL IS MOSTLY DYNAMIC AND CAN POTENTIALLY BE MANIPULATED TO PREVENT OR REVERSE THE UNCONTROLLED EXPRESSION OF GENES, A TRAIT THAT RENDERS THEM PUTATIVE THERAPEUTIC TARGETS. IN THE CURRENT REVIEW, WE SYSTEMATICALLY STUDIED AND PRESENT AVAILABLE DATA ON EPIGENETIC ALTERATIONS IMPLICATED IN THROMBOSIS DERIVED FROM HUMAN STUDIES. EVIDENCE OF EPIGENETIC ALTERATIONS IS OBSERVED IN SEVERAL THROMBOTIC DISEASES SUCH AS CORONARY ARTERY DISEASE AND CEREBROVASCULAR DISEASE, PREECLAMPSIA AND ANTIPHOSPHOLIPID SYNDROME. DIFFERENTIAL CPG METHYLATION AND SPECIFIC HISTONE PTMS THAT CONTROL TRANSCRIPTION OF PROTHROMBOTIC AND PROINFLAMMATORY GENES HAVE ALSO BEEN ASSOCIATED WITH PREDISPOSING FACTORS OF THROMBOSIS AND CVD, SUCH US SMOKING, AIR POLLUTION, HYPERTRIGLYCERIDEMIA, OCCUPATIONAL EXPOSURE TO PARTICULATE MATTER AND COMORBIDITIES INCLUDING CANCER, CHRONIC OBSTRUCTIVE PULMONARY DISEASE AND CHRONIC KIDNEY DISEASE. THESE CLINICAL OBSERVATIONS ARE FURTHER SUPPORTED BY IN VITRO EXPERIMENTS AND INDICATE THAT EPIGENETIC REGULATION AFFECTS THE PATHOPHYSIOLOGY OF THROMBOTIC DISORDERS WITH POTENTIAL DIAGNOSTIC OR THERAPEUTIC UTILITY. 2019 11 4300 28 MICRORNA-19A CONTRIBUTES TO THE EPIGENETIC REGULATION OF TISSUE FACTOR IN DIABETES. BACKGROUND: DIABETES MELLITUS IS CHARACTERIZED BY CHRONIC VASCULAR DISORDER AND PRESENTS A MAIN RISK FACTOR FOR CARDIOVASCULAR MORTALITY. IN PARTICULAR, HYPERGLYCAEMIA AND INFLAMMATORY CYTOKINES INDUCE VASCULAR CIRCULATING TISSUE FACTOR (TF) THAT PROMOTES PRO-THROMBOTIC CONDITIONS IN DIABETES. IT HAS RECENTLY BECOME EVIDENT THAT ALTERATIONS OF THE POST-TRANSCRIPTIONAL REGULATION OF TF VIA SPECIFIC MICRORNA(MIR)S, SUCH AS MIR-126, CONTRIBUTE TO THE PATHOGENESIS OF DIABETES AND ITS COMPLICATIONS. THE ENDOTHELIAL MIR-19A IS INVOLVED IN VASCULAR HOMEOSTASIS AND ATHEROPROTECTION. HOWEVER, ITS ROLE IN DIABETES-RELATED THROMBOGENICITY IS UNKNOWN. UNDERSTANDING MIR-NETWORKS REGULATING PROCOAGULABILITY IN DIABETES MAY HELP TO DEVELOP NEW TREATMENT OPTIONS PREVENTING VASCULAR COMPLICATIONS. METHODS AND RESULTS: PLASMA OF 44 PATIENTS WITH KNOWN DIABETES WAS ASSESSED FOR THE EXPRESSION OF MIR-19A, TF PROTEIN, TF ACTIVITY, AND MARKERS FOR VASCULAR INFLAMMATION. HIGH MIR-19A EXPRESSION WAS ASSOCIATED WITH REDUCED TF PROTEIN, TF-MEDIATED PROCOAGULABILITY, AND VASCULAR INFLAMMATION BASED ON EXPRESSION OF VASCULAR ADHESION MOLECULE-1 AND LEUKOCYTE COUNT. WE FOUND PLASMA EXPRESSION OF MIR-19A TO STRONGLY CORRELATE WITH MIR-126. MIR-19A REDUCED THE TF EXPRESSION ON MRNA AND PROTEIN LEVEL IN HUMAN MICROVASCULAR ENDOTHELIAL CELLS (HMEC) AS WELL AS TF ACTIVITY IN HUMAN MONOCYTES (THP-1), WHILE ANTI-MIR-19A INCREASED THE TF EXPRESSION. INTERESTINGLY, MIR-19A INDUCED VCAM EXPRESSION IN HMEC. HOWEVER, MIR-19A AND MIR-126 CO-TRANSFECTION REDUCED TOTAL ENDOTHELIAL VCAM EXPRESSION AND EXHIBITED ADDITIVE INHIBITION OF A LUCIFERASE REPORTER CONSTRUCT CONTAINING THE F3 3'UTR. CONCLUSIONS: WHILE BOTH MIRS HAVE DIFFERENTIAL FUNCTIONS ON ENDOTHELIAL VCAM EXPRESSION, MIR-19A AND MIR-126 COOPERATE TO EXHIBIT ANTI-THROMBOTIC PROPERTIES VIA REGULATING VASCULAR TF EXPRESSION. MODULATING THE POST-TRANSCRIPTIONAL CONTROL OF TF IN DIABETES MAY PROVIDE A FUTURE ANTI-THROMBOTIC AND ANTI-INFLAMMATORY THERAPY. 2018 12 1712 36 DYSFUNCTIONAL VASCULAR ENDOTHELIUM AS A DRIVER OF ATHEROSCLEROSIS: EMERGING INSIGHTS INTO PATHOGENESIS AND TREATMENT. ATHEROSCLEROSIS, THE CHRONIC ACCUMULATION OF CHOLESTEROL-RICH PLAQUE WITHIN ARTERIES, IS ASSOCIATED WITH A BROAD SPECTRUM OF CARDIOVASCULAR DISEASES INCLUDING MYOCARDIAL INFARCTION, AORTIC ANEURYSM, PERIPHERAL VASCULAR DISEASE, AND STROKE. ATHEROSCLEROTIC CARDIOVASCULAR DISEASE REMAINS A LEADING CAUSE OF MORTALITY IN HIGH-INCOME COUNTRIES AND RECENT YEARS HAVE WITNESSED A NOTABLE INCREASE IN PREVALENCE WITHIN LOW- AND MIDDLE-INCOME REGIONS OF THE WORLD. CONSIDERING THIS PROMINENT AND EVOLVING GLOBAL BURDEN, THERE IS A NEED TO IDENTIFY THE CELLULAR MECHANISMS THAT UNDERLIE THE PATHOGENESIS OF ATHEROSCLEROSIS TO DISCOVER NOVEL THERAPEUTIC TARGETS FOR PREVENTING OR MITIGATING ITS CLINICAL SEQUELAE. DESPITE DECADES OF RESEARCH, WE STILL DO NOT FULLY UNDERSTAND THE COMPLEX CELL-CELL INTERACTIONS THAT DRIVE ATHEROSCLEROSIS, BUT NEW INVESTIGATIVE APPROACHES ARE RAPIDLY SHEDDING LIGHT ON THESE ESSENTIAL MECHANISMS. THE VASCULAR ENDOTHELIUM RESIDES AT THE INTERFACE OF SYSTEMIC CIRCULATION AND THE UNDERLYING VESSEL WALL AND PLAYS AN ESSENTIAL ROLE IN GOVERNING PATHOPHYSIOLOGICAL PROCESSES DURING ATHEROGENESIS. IN THIS REVIEW, WE PRESENT EMERGING EVIDENCE THAT IMPLICATES THE ACTIVATED ENDOTHELIUM AS A DRIVER OF ATHEROSCLEROSIS BY DIRECTING SITE-SPECIFICITY OF PLAQUE FORMATION AND BY PROMOTING PLAQUE DEVELOPMENT THROUGH INTRACELLULAR PROCESSES, WHICH REGULATE ENDOTHELIAL CELL PROLIFERATION AND TURNOVER, METABOLISM, PERMEABILITY, AND PLASTICITY. MOREOVER, WE HIGHLIGHT NOVEL MECHANISMS OF INTERCELLULAR COMMUNICATION BY WHICH ENDOTHELIAL CELLS MODULATE THE ACTIVITY OF KEY VASCULAR CELL POPULATIONS INVOLVED IN ATHEROGENESIS, AND DISCUSS HOW ENDOTHELIAL CELLS CONTRIBUTE TO RESOLUTION BIOLOGY - A PROCESS THAT IS DYSREGULATED IN ADVANCED PLAQUES. FINALLY, WE DESCRIBE IMPORTANT FUTURE DIRECTIONS FOR PRECLINICAL ATHEROSCLEROSIS RESEARCH, INCLUDING EPIGENETIC AND TARGETED THERAPIES, TO LIMIT THE PROGRESSION OF ATHEROSCLEROSIS IN AT-RISK OR AFFECTED PATIENTS. 2021 13 3344 27 HISTONE DEACETYLASES (HDACS) AND ATHEROSCLEROSIS: A MECHANISTIC AND PHARMACOLOGICAL REVIEW. ATHEROSCLEROSIS (AS), THE MOST COMMON UNDERLYING PATHOLOGY FOR CORONARY ARTERY DISEASE, IS A CHRONIC INFLAMMATORY, PROLIFERATIVE DISEASE IN LARGE- AND MEDIUM-SIZED ARTERIES. THE VASCULAR ENDOTHELIUM IS IMPORTANT FOR MAINTAINING VASCULAR HEALTH. ENDOTHELIAL DYSFUNCTION IS A CRITICAL EARLY EVENT LEADING TO AS, WHICH IS A MAJOR RISK FACTOR FOR STROKE AND MYOCARDIAL INFARCTION. ACCUMULATING EVIDENCE HAS SUGGESTED THE CRITICAL ROLES OF HISTONE DEACETYLASES (HDACS) IN REGULATING VASCULAR CELL HOMEOSTASIS AND AS. THE PURPOSE OF THIS REVIEW IS TO PRESENT AN UPDATED VIEW ON THE ROLES OF HDACS (CLASS I, CLASS II, CLASS IV) AND HDAC INHIBITORS IN VASCULAR DYSFUNCTION AND AS. WE ALSO ELABORATE ON THE NOVEL THERAPEUTIC TARGETS AND AGENTS IN ATHEROSCLEROTIC CARDIOVASCULAR DISEASES. 2020 14 5953 33 TARGETS IN MPNS AND POTENTIAL THERAPEUTICS. PHILADELPHIA-NEGATIVE CLASSICAL MYELOPROLIFERATIVE NEOPLASMS (MPNS), INCLUDING POLYCYTHEMIA VERA (PV), ESSENTIAL THROMBOCYTHEMIA (ET) AND PRIMARY MYELOFIBROSIS (PMF), ARE CLONAL HEMOPATHIES THAT EMERGE IN THE HEMATOPOIETIC STEM CELL (HSC) COMPARTMENT. MPN DRIVER MUTATIONS ARE RESTRICTED TO SPECIFIC EXONS (14 AND 12) OF JANUS KINASE 2 (JAK2), THROMBOPOIETIN RECEPTOR (MPL/TPOR) AND CALRETICULIN (CALR) GENES, ARE INVOLVED DIRECTLY IN CLONAL MYELOPROLIFERATION AND GENERATE THE MPN PHENOTYPE. AS A RESULT, AN INCREASED NUMBER OF FULLY FUNCTIONAL ERYTHROCYTES, PLATELETS AND LEUKOCYTES IS OBSERVED IN THE PERIPHERAL BLOOD. NEVERTHELESS, THE COMPLEXITY AND HETEROGENEITY OF MPN CLINICAL PHENOTYPES CANNOT BE SOLELY EXPLAINED BY THE TYPE OF DRIVER MUTATION. OTHER FACTORS, SUCH AS ADDITIONAL SOMATIC MUTATIONS AFFECTING EPIGENETIC REGULATORS OR SPLICEOSOMES COMPONENTS, MUTANT ALLELE BURDENS AND MODIFIERS OF SIGNALING BY DRIVER MUTANTS, CLONAL ARCHITECTURE AND THE ORDER OF MUTATION ACQUISITION, SIGNALING EVENTS THAT OCCUR DOWNSTREAM OF A DRIVER MUTATION, THE PRESENCE OF SPECIFIC GERM-LINE VARIANTS, THE INTERACTION OF THE NEOPLASTIC CLONE WITH BONE MARROW MICROENVIRONMENT AND CHRONIC INFLAMMATION, ALL CAN MODULATE THE DISEASE PHENOTYPE, INFLUENCE THE MPN CLINICAL COURSE AND THEREFORE, MIGHT BE USEFUL THERAPEUTIC TARGETS. 2022 15 4322 32 MICRORNAS IN MYELOPROLIFERATIVE NEOPLASMS. THE CHRONIC MYELOPROLIFERATIVE NEOPLASMS (MPN), INCLUDING POLYCYTHAEMIA VERA (PV), ESSENTIAL THROMBOCYTHAEMIA (ET) AND PRIMARY MYELOFIBROSIS (PMF), ARE CLONAL STEM CELL DISORDERS CHARACTERIZED BY DYSREGULATED HAEMATOPOIETIC STEM CELL EXPANSION AND PRODUCTION OF RED CELLS, WHITE CELLS AND PLATELETS ALONE OR IN COMBINATION. AN ACQUIRED MUTATION JAK2(V617F) CAN BE FOUND IN ALL THREE DISORDERS AND SHOWS MANY OF THE PHENOTYPIC ABNORMALITIES OF THE DISEASES IN MURINE MODELS. THE DISEASE PHENOTYPE IS ALSO INFLUENCED BY OTHER UNKNOWN GENETIC OR EPIGENETIC FACTORS. MICRORNAS (MIRNA) ARE 18-24 NUCLEOTIDE SINGLE-STRANDED NON-PROTEIN-CODING RNAS THAT FUNCTION PRIMARILY AS GENE REPRESSORS BY BINDING TO THEIR TARGET MESSENGER RNAS. THERE IS GROWING EVIDENCE THAT MIRNAS REGULATE HAEMATOPOIESIS IN BOTH HAEMATOPOIETIC STEM CELLS AND COMMITTED PROGENITOR CELLS. HERE, WE REVIEW THE FIELD OF MIRNA BIOLOGY AND ITS REGULATORY ROLES IN NORMAL HAEMATOPOIESIS WITH AN EMPHASIS ON MIRNA DEREGULATIONS IN MPNS. CONTINUED RESEARCH INTO HOW MIRNAS IMPACT JAK2(V617F) CLONAL EXPANSION, DIFFERENTIAL HAEMATOPOIESIS AMONG DIFFERENT MPNS, DISEASE PROGRESSION AND LEUKAEMIA TRANSFORMATION WILL LEAD TO A BETTER UNDERSTANDING OF THE DEVELOPMENT OF THESE DISORDERS, THEIR CLINICAL MANIFESTATIONS, AND THEIR TREATMENT. 2013 16 6413 19 THE STATE OF ART OF REGENERATIVE THERAPY IN CARDIOVASCULAR ISCHEMIC DISEASE: BIOLOGY, SIGNALING PATHWAYS, AND EPIGENETICS OF ENDOTHELIAL PROGENITOR CELLS. ISCHEMIC HEART DISEASE IS CURRENTLY A MAJOR CAUSE OF MORTALITY AND MORBIDITY WORLDWIDE. NEVERTHELESS, THE ACTUAL THERAPEUTIC SCENARIO DOES NOT TARGET MYOCARDIAL CELL REGENERATION AND CONSEQUENTLY, THE PROGRESSION TOWARD THE LATE STAGE OF CHRONIC HEART FAILURE IS COMMON. ENDOTHELIAL PROGENITOR CELLS (EPCS) ARE BONE MARROW-DERIVED STEM CELLS THAT CONTRIBUTE TO THE HOMEOSTASIS OF THE ENDOTHELIAL WALL IN ACUTE AND CHRONIC ISCHEMIC DISEASE. CALCIUM MODULATION AND OTHER MOLECULAR PATHWAYS (NOTCH, VEGFR, AND CXCR4) CONTRIBUTE TO EPC PROLIFERATION AND DIFFERENTIATION. THE PRESENT REVIEW PROVIDES A SUMMARY OF EPC BIOLOGY WITH A PARTICULAR FOCUS ON THE REGULATORY PATHWAYS OF EPCS AND DESCRIBES PROMISING APPLICATIONS FOR CARDIOVASCULAR CELL THERAPY. 2020 17 5933 34 TARGETING EPIGENETICS AND NON-CODING RNAS IN ATHEROSCLEROSIS: FROM MECHANISMS TO THERAPEUTICS. ATHEROSCLEROSIS, THE PRINCIPAL CAUSE OF CARDIOVASCULAR DEATH WORLDWIDE, IS A PATHOLOGICAL DISEASE CHARACTERIZED BY FIBRO-PROLIFERATION, CHRONIC INFLAMMATION, LIPID ACCUMULATION, AND IMMUNE DISORDER IN THE VESSEL WALL. AS THE ATHEROMATOUS PLAQUES DEVELOP INTO ADVANCED STAGE, THE VULNERABLE PLAQUES ARE PRONE TO RUPTURE, WHICH CAUSES ACUTE CARDIOVASCULAR EVENTS, INCLUDING ISCHEMIC STROKE AND MYOCARDIAL INFARCTION. EMERGING EVIDENCE HAS SUGGESTED THAT ATHEROSCLEROSIS IS ALSO AN EPIGENETIC DISEASE WITH THE INTERPLAY OF MULTIPLE EPIGENETIC MECHANISMS. THE EPIGENETIC BASIS OF ATHEROSCLEROSIS HAS TRANSFORMED OUR KNOWLEDGE OF EPIGENETICS FROM AN IMPORTANT BIOLOGICAL PHENOMENON TO A BURGEONING FIELD IN CARDIOVASCULAR RESEARCH. HERE, WE PROVIDE A SYSTEMATIC AND UP-TO-DATE OVERVIEW OF THE CURRENT KNOWLEDGE OF THREE DISTINCT BUT INTERRELATED EPIGENETIC PROCESSES (INCLUDING DNA METHYLATION, HISTONE METHYLATION/ACETYLATION, AND NON-CODING RNAS), IN ATHEROSCLEROTIC PLAQUE DEVELOPMENT AND INSTABILITY. MECHANISTIC AND CONCEPTUAL ADVANCES IN UNDERSTANDING THE BIOLOGICAL ROLES OF VARIOUS EPIGENETIC MODIFIERS IN REGULATING GENE EXPRESSION AND FUNCTIONS OF ENDOTHELIAL CELLS (VASCULAR HOMEOSTASIS, LEUKOCYTE ADHESION, ENDOTHELIAL-MESENCHYMAL TRANSITION, ANGIOGENESIS, AND MECHANOTRANSDUCTION), SMOOTH MUSCLE CELLS (PROLIFERATION, MIGRATION, INFLAMMATION, HYPERTROPHY, AND PHENOTYPIC SWITCH), AND MACROPHAGES (DIFFERENTIATION, INFLAMMATION, FOAM CELL FORMATION, AND POLARIZATION) ARE DISCUSSED. THE INHERENTLY DYNAMIC NATURE AND REVERSIBILITY OF EPIGENETIC REGULATION, ENABLES THE POSSIBILITY OF EPIGENETIC THERAPY BY TARGETING EPIGENETIC "WRITERS", "READERS", AND "ERASERS". SEVERAL FOOD DRUG ADMINISTRATION-APPROVED SMALL-MOLECULE EPIGENETIC DRUGS SHOW PROMISE IN PRE-CLINICAL STUDIES FOR THE TREATMENT OF ATHEROSCLEROSIS. FINALLY, WE DISCUSS POTENTIAL THERAPEUTIC IMPLICATIONS AND CHALLENGES FOR FUTURE RESEARCH INVOLVING CARDIOVASCULAR EPIGENETICS, WITH AN AIM TO PROVIDE A TRANSLATIONAL PERSPECTIVE FOR IDENTIFYING NOVEL BIOMARKERS OF ATHEROSCLEROSIS, AND TRANSFORMING PRECISION CARDIOVASCULAR RESEARCH AND DISEASE THERAPY IN MODERN ERA OF EPIGENETICS. 2019 18 3776 30 INTERACTIONS BETWEEN DYSLIPIDEMIA AND THE IMMUNE SYSTEM AND THEIR RELEVANCE AS PUTATIVE THERAPEUTIC TARGETS IN ATHEROSCLEROSIS. CARDIOVASCULAR DISEASE (CVD) CONTINUES TO BE A LEADING CAUSE OF DEATH WORLDWIDE WITH ATHEROSCLEROSIS BEING THE MAJOR UNDERLYING PATHOLOGY. THE INTERPLAY BETWEEN LIPIDS AND IMMUNE CELLS IS BELIEVED TO BE A DRIVING FORCE IN THE CHRONIC INFLAMMATION OF THE ARTERIAL WALL DURING ATHEROGENESIS. ATHEROSCLEROSIS IS INITIATED AS LIPID PARTICLES ACCUMULATE AND BECOME TRAPPED IN VESSEL WALLS. THE SUBSEQUENT IMMUNE RESPONSE, INVOLVING BOTH ADAPTIVE AND IMMUNE CELLS, PROGRESSES PLAQUE DEVELOPMENT, WHICH MAY BE EXACERBATED UNDER DYSLIPIDEMIC CONDITIONS. BROAD EVIDENCE, ESPECIALLY FROM ANIMAL MODELS, CLEARLY DEMONSTRATES THE EFFECT OF LIPIDS ON IMMUNE CELLS FROM THEIR DEVELOPMENT IN THE BONE MARROW TO THEIR PHENOTYPIC SWITCHING IN CIRCULATION. INTERESTINGLY, RECENT RESEARCH HAS ALSO SHOWN A LONG-LASTING EPIGENETIC SIGNATURE FROM LIPIDS ON IMMUNE CELLS. TRADITIONALLY, CARDIOVASCULAR THERAPIES HAVE APPROACHED ATHEROSCLEROSIS THROUGH LIPID-LOWERING MEDICATIONS BECAUSE, UNTIL RECENTLY, ANTI-INFLAMMATORY THERAPIES HAVE BEEN LARGELY UNSUCCESSFUL IN CLINICAL TRIALS. HOWEVER, THE RECENT CANAKINUMAB ANTIINFLAMMATORY THROMBOSIS OUTCOMES STUDY (CANTOS) PROVIDED PIVOTAL SUPPORT OF THE INFLAMMATORY HYPOTHESIS OF ATHEROSCLEROSIS IN MAN SPURRING ON ANTI-INFLAMMATORY STRATEGIES TO TREAT ATHEROSCLEROSIS. IN THIS REVIEW, WE DESCRIBE THE INTERACTIONS BETWEEN LIPIDS AND IMMUNE CELLS ALONG WITH THEIR SPECIFIC OUTCOMES AS WELL AS DISCUSS THEIR FUTURE PERSPECTIVE AS POTENTIAL CARDIOVASCULAR TARGETS. 2019 19 54 21 A DRY IMMERSION MODEL OF MICROGRAVITY MODULATES PLATELET PHENOTYPE, MIRNA SIGNATURE, AND CIRCULATING PLASMA PROTEIN BIOMARKER PROFILE. GROUND BASED RESEARCH MODALITIES OF MICROGRAVITY HAVE BEEN PROPOSED AS INNOVATIVE METHODS TO INVESTIGATE THE AETIOLOGY OF CHRONIC AGE-RELATED CONDITIONS SUCH AS CARDIOVASCULAR DISEASE. DRY IMMERSION (DI), HAS BEEN EFFECTIVELY USED TO INTERROGATE THE SEQUELAE OF PHYSICAL INACTIVITY (PI) AND MICROGRAVITY ON MULTIPLE PHYSIOLOGICAL SYSTEMS. HEREIN WE LOOK AT THE CAUSA ET EFFECTUS OF 3-DAY DI ON PLATELET PHENOTYPE, AND CORRELATE WITH BOTH MIROMIC AND CIRCULATING BIOMARKER EXPRESSION. THE MIROMIC PROFILE OF PLATELETS IS REFLECTIVE OF PHENOTYPE, WHICH ITSELF IS SENSITIVE AND MALLEABLE TO THE EXPOSOME, UNDERGOING RESPONSIVE TRANSITIONS IN ORDER TO FULFIL PLATELETS ROLE IN THROMBOSIS AND HAEMOSTASIS. HETEROGENEOUS PLATELET SUBPOPULATIONS CIRCULATE AT ANY GIVEN TIME, WITH VARYING DEGREES OF SENSITIVITY TO ACTIVATION. EMPLOYING A DI MODEL, WE INVESTIGATE THE EFFECT OF ACUTE PI ON PLATELET FUNCTION IN 12 HEALTHY MALES. 3-DAY DI RESULTED IN A SIGNIFICANT INCREASE IN PLATELET COUNT, PLATELETCRIT, PLATELET ADHESION, AGGREGATION, AND A MODEST ELEVATION OF PLATELET REACTIVITY INDEX (PRI). WE IDENTIFIED 15 PROTEIN BIOMARKERS AND 22 MIRNA WHOSE EXPRESSION LEVELS WERE ALTERED AFTER DI. A 3-DAY DI MODEL OF MICROGRAVITY/PHYSICAL INACTIVITY INDUCED A PROTHROMBOTIC PLATELET PHENOTYPE WITH AN UNIQUE PLATELET MIRNA SIGNATURE, INCREASED PLATELET COUNT AND PLATELETCRIT. THIS CORRELATED WITH A UNIQUE CIRCULATING PROTEIN BIOMARKER SIGNATURE. TAKEN TOGETHER, THESE FINDINGS HIGHLIGHT PLATELETS AS SENSITIVE ADAPTIVE SENTINELS AND FUNCTIONAL BIOMARKERS OF EPIGENETIC DRIFT WITHIN THE CARDIOVASCULAR COMPARTMENT. 2021 20 4303 25 MICRORNA-223 INHIBITS TISSUE FACTOR EXPRESSION IN VASCULAR ENDOTHELIAL CELLS. OBJECTIVE: ATHEROSCLEROSIS IS A CHRONIC INFLAMMATORY PROCESS, IN WHICH VASCULAR ENDOTHELIAL CELLS (ECS) BECOME DYSFUNCTIONAL OWING TO THE EFFECTS OF CHEMICAL SUBSTANCES, SUCH AS INFLAMMATORY FACTOR AND GROWTH FACTORS. TISSUE FACTOR (TF) EXPRESSION IS INDUCED BY THE ABOVE CHEMICAL SUBSTANCES IN ACTIVATED ECS. TF INITIATES THROMBOSIS ON DISRUPTED ATHEROSCLEROTIC PLAQUES WHICH PLAYS AN ESSENTIAL ROLE DURING THE ONSET OF ACUTE CORONARY SYNDROMES (ACS). INCREASING EVIDENCES SUGGEST THE IMPORTANT ROLE OF MICRORNAS AS EPIGENETIC REGULATORS OF ATHEROSCLEROTIC DISEASE. THE AIM OF OUR STUDY IS TO IDENTIFY IF MICRORNA-223 (MIR-223) TARGETS TF IN ECS. METHODS AND RESULTS: BIOINFORMATIC ANALYSIS SHOWED THAT TF IS A TARGET CANDIDATE OF MIR-223. WESTERN BLOTTING ANALYSIS REVEALED THAT TUMOR NECROSIS FACTOR ALPHA (TNF-ALPHA) INCREASED TF EXPRESSION IN AORTA OF C57BL/6J MICE AND CULTURED ECS (EA.HY926 CELLS AND HUVEC) AFTER 4 H TREATMENT. IN TNF-ALPHA TREATED ECS, TF MRNA WAS ALSO INCREASED MEASURED BY REAL-TIME PCR. REAL-TIME PCR RESULTS SHOWED THAT MIR-223 LEVELS WERE DOWNREGULATED IN TNF-ALPHA-TREATED AORTA OF C57BL/6J MICE AND CULTURED ECS. TRANSFECTION OF ECS WITH MIR-223 MIMIC OR MIR-223 INHIBITOR MODIFIED TF EXPRESSION BOTH IN MRNA AND PROTEIN LEVELS. LUCIFERASE ASSAYS CONFIRMED THAT MIR-223 SUPPRESSED TF EXPRESSION BY BINDING TO THE SEQUENCE OF TF 3'-UNTRANSLATED REGIONS (3'UTR). TF PROCOAGULANT ACTIVITY WAS INHIBITED BY OVEREXPRESSING MIR-223 WITH OR WITHOUT TNF-ALPHA STIMULATION. CONCLUSIONS: MIR-223-MEDIATED SUPPRESSION OF TF EXPRESSION PROVIDES A NOVEL MOLECULAR MECHANISM FOR THE REGULATION OF COAGULATION CASCADE, AND SUGGESTS A CLUE AGAINST THROMBOGENESIS DURING THE PROCESS OF ATHEROSCLEROTIC PLAQUE RUPTURE. 2014