1 1339 167 DESIGN, SYNTHESIS, BIOLOGICAL EVALUATION, AND STRUCTURAL CHARACTERIZATION OF POTENT HISTONE DEACETYLASE INHIBITORS BASED ON CYCLIC ALPHA/BETA-TETRAPEPTIDE ARCHITECTURES. HISTONE DEACETYLASES (HDACS) ARE A FAMILY OF ENZYMES FOUND IN BACTERIA, FUNGI, PLANTS, AND ANIMALS THAT PROFOUNDLY AFFECT CELLULAR FUNCTION BY CATALYZING THE REMOVAL OF ACETYL GROUPS FROM -N-ACETYLATED LYSINE RESIDUES OF VARIOUS PROTEIN SUBSTRATES INCLUDING HISTONES, TRANSCRIPTION FACTORS, ALPHA-TUBULIN, AND NUCLEAR IMPORTERS. ALTHOUGH THE PRECISE ROLES OF HDAC ISOFORMS IN CELLULAR FUNCTION ARE NOT YET COMPLETELY UNDERSTOOD, INHIBITION OF HDAC ACTIVITY HAS EMERGED AS A PROMISING APPROACH FOR REVERSING THE ABERRANT EPIGENETIC STATES ASSOCIATED WITH CANCER AND OTHER CHRONIC DISEASES. POTENT NEW ISOFORM-SELECTIVE HDAC INHIBITORS WOULD THEREFORE HELP EXPAND OUR UNDERSTANDING OF THE HDAC ENZYMES AND REPRESENT ATTRACTIVE LEAD COMPOUNDS FOR DRUG DESIGN, ESPECIALLY IF COMBINED WITH HIGH-RESOLUTION STRUCTURAL ANALYSES OF SUCH INHIBITORS TO SHED LIGHT ON THE THREE-DIMENSIONAL PHARMACOPHORIC FEATURES NECESSARY FOR THE FUTURE DESIGN OF MORE POTENT AND SELECTIVE COMPOUNDS. HERE WE PRESENT STRUCTURAL AND FUNCTIONAL ANALYSES OF A SERIES OF BETA-AMINO-ACID-CONTAINING HDAC INHIBITORS INSPIRED BY CYCLIC TETRAPEPTIDE NATURAL PRODUCTS. TO SURVEY A DIVERSE ENSEMBLE OF PHARMACOPHORIC CONFIGURATIONS, WE SYSTEMATICALLY VARIED THE POSITION OF THE BETA-AMINO ACID, AMINO ACID CHIRALITY, FUNCTIONALIZATION OF THE ZN(2+)-COORDINATING AMINO ACID SIDE CHAIN, AND ALKYLATION OF THE BACKBONE AMIDE NITROGEN ATOMS AROUND THE MACROCYCLE. IN MANY CASES, THE COMPOUNDS WERE A SINGLE CONFORMATION IN SOLUTION AND EXHIBITED POTENT ACTIVITIES AGAINST A NUMBER OF HDAC ISOFORMS AS WELL AS EFFECTIVE ANTIPROLIFERATIVE AND CYTOTOXIC ACTIVITIES AGAINST HUMAN TUMOR CELLS. HIGH-RESOLUTION NMR SOLUTION STRUCTURES WERE DETERMINED FOR A SELECTION OF THE INHIBITORS, PROVIDING A USEFUL MEANS OF CORRELATING DETAILED STRUCTURAL INFORMATION WITH POTENCY. THE STRUCTURE-BASED APPROACH DESCRIBED HERE IS EXPECTED TO FURNISH VALUABLE INSIGHTS TOWARD THE FUTURE DESIGN OF MORE SELECTIVE HDAC INHIBITORS. 2009 2 5937 41 TARGETING HISTONE DEACETYLASE ACTIVITY IN RHEUMATOID ARTHRITIS AND ASTHMA AS PROTOTYPES OF INFLAMMATORY DISEASE: SHOULD WE KEEP OUR HATS ON? CELLULAR ACTIVATION, PROLIFERATION AND SURVIVAL IN CHRONIC INFLAMMATORY DISEASES IS REGULATED NOT ONLY BY ENGAGEMENT OF SIGNAL TRANS-DUCTION PATHWAYS THAT MODULATE TRANSCRIPTION FACTORS REQUIRED FOR THESE PROCESSES, BUT ALSO BY EPIGENETIC REGULATION OF TRANSCRIPTION FACTOR ACCESS TO GENE PROMOTER REGIONS. HISTONE ACETYL TRANSFERASES COORDINATE THE RECRUITMENT AND ACTIVATION OF TRANSCRIPTION FACTORS WITH CONFORMATIONAL CHANGES IN HISTONES THAT ALLOW GENE PROMOTER EXPOSURE. HISTONE DEACETYLASES (HDACS) COUNTERACT HISTONE ACETYL TRANSFERASE ACTIVITY THROUGH THE TARGETING OF BOTH HISTONES AS WELL AS NONHISTONE SIGNAL TRANSDUCTION PROTEINS IMPORTANT IN INFLAMMATION. NUMEROUS STUDIES HAVE INDICATED THAT DEPRESSED HDAC ACTIVITY IN PATIENTS WITH INFLAMMATORY AIRWAY DISEASES MAY CONTRIBUTE TO LOCAL PROINFLAMMATORY CYTOKINE PRODUCTION AND DIMINISH PATIENT RESPONSES TO CORTICOSTEROID TREATMENT. RECENT OBSERVATIONS THAT HDAC ACTIVITY IS DEPRESSED IN RHEUMATOID ARTHRITIS PATIENT SYNOVIAL TISSUE HAVE PREDICTED THAT STRATEGIES RESTORING HDAC FUNCTION MAY BE THERAPEUTIC IN THIS DISEASE AS WELL. PHARMACOLOGICAL INHIBITORS OF HDAC ACTIVITY, HOWEVER, HAVE DEMONSTRATED POTENT THERAPEUTIC EFFECTS IN ANIMAL MODELS OF ARTHRITIS AND OTHER CHRONIC INFLAMMATORY DISEASES. IN THE PRESENT REVIEW WE ASSESS AND RECONCILE THESE OUTWARDLY PARADOXICAL STUDY RESULTS TO PROVIDE A WORKING MODEL FOR HOW ALTERATIONS IN HDAC ACTIVITY MAY CONTRIBUTE TO PATHOLOGY IN RHEUMATOID ARTHRITIS, AND HIGHLIGHT KEY QUESTIONS TO BE ANSWERED IN THE PRECLINICAL EVALUATION OF COMPOUNDS MODULATING THESE ENZYMES. 2008 3 834 26 CHEMICAL BIOLOGY OF LYSINE DEMETHYLASES. ABNORMAL LEVELS OF DNA METHYLATION AND/OR HISTONE MODIFICATIONS ARE OBSERVED IN PATIENTS WITH A WIDE VARIETY OF CHRONIC DISEASES. METHYLATION OF LYSINES WITHIN HISTONE TAILS IS A KEY MODIFICATION THAT CONTRIBUTES TO INCREASED GENE EXPRESSION OR REPRESSION DEPENDING ON THE SPECIFIC RESIDUE AND DEGREE OF METHYLATION, WHICH IS IN TURN CONTROLLED BY THE INTERPLAY OF LYSINE METHYL TRANSFERASES AND DEMETHYLASES. DRUGS THAT TARGET THESE AND OTHER ENZYMES CONTROLLING CHROMATIN MODIFICATIONS CAN MODULATE THE EXPRESSION OF CLUSTERS OF GENES, POTENTIALLY OFFERING HIGHER THERAPEUTIC EFFICACY THAN CLASSICAL AGENTS ACTING ON DOWNSTREAM BIOCHEMICAL PATHWAYS THAT ARE SUSCEPTIBLE TO DEGENERACY. LYSINE DEMETHYLASES, FIRST DISCOVERED IN 2004, ARE THE SUBJECT OF INCREASING INTEREST AS THERAPEUTIC TARGETS. THIS REVIEW PROVIDES AN OVERVIEW OF RECENT FINDINGS IMPLICATING LYSINE DEMETHYLASES IN A RANGE OF THERAPEUTIC AREAS INCLUDING ONCOLOGY, IMMUNOINFLAMMATION, METABOLIC DISORDERS, NEUROSCIENCE, VIROLOGY AND REGENERATIVE MEDICINE, TOGETHER WITH A SUMMARY OF RECENT ADVANCES IN STRUCTURAL BIOLOGY AND SMALL MOLECULE INHIBITOR DISCOVERY, SUPPORTING THE TRACTABILITY OF THE PROTEIN FAMILY FOR THE DEVELOPMENT OF SELECTIVE DRUGLIKE INHIBITORS. 2011 4 5562 35 ROLE OF HISTONE DEACETYLASES IN PANCREAS: IMPLICATIONS FOR PATHOGENESIS AND THERAPY. IN THE LAST YEARS, OUR KNOWLEDGE OF THE PATHOGENESIS IN ACUTE AND CHRONIC PANCREATITIS (AP/CP) AS WELL AS IN PANCREATIC CANCEROGENESIS HAS SIGNIFICANTLY DIVERSIFIED. NEVERTHELESS, THE MEDICINAL THERAPEUTIC OPTIONS ARE STILL LIMITED AND THERAPEUTIC SUCCESS AND PATIENT OUTCOME ARE POOR. EPIGENETIC DEREGULATION OF GENE EXPRESSION IS KNOWN TO CONTRIBUTE TO DEVELOPMENT AND PROGRESSION OF AP AND CP AS WELL AS OF PANCREATIC CANCER. THEREFORE, THE SELECTIVE INHIBITION OF ABERRANTLY ACTIVE EPIGENETIC REGULATORS CAN BE AN EFFECTIVE OPTION FOR FUTURE THERAPIES. HISTONE DEACETYLASES (HDACS) ARE ENZYMES THAT REMOVE AN ACETYL GROUP FROM HISTONE TAILS, THEREBY CAUSING CHROMATIN COMPACTION AND REPRESSION OF TRANSCRIPTION. IN THIS REVIEW WE PRESENT AN OVERVIEW OF THE CURRENTLY AVAILABLE LITERATURE ADDRESSING THE ROLE OF HDACS IN THE PANCREAS AND IN PANCREATIC DISEASES. IN PANCREATIC CANCEROGENESIS, HDACS PLAY A ROLE IN THE IMPORTANT PROCESS OF EPITHELIAL-MESENCHYMAL-TRANSITION, UBIQUITIN-PROTEASOME PATHWAY AND, HYPOXIA-INDUCIBLE-FACTOR-1-ANGIOGENESIS. FINALLY, WE FOCUS ON HDACS AS POTENTIAL THERAPEUTIC TARGETS BY SUMMARIZING CURRENTLY AVAILABLE HISTONE DEACETYLASE INHIBITORS. 2015 5 3207 34 HDACI: CELLULAR EFFECTS, OPPORTUNITIES FOR RESTORATIVE DENTISTRY. ACETYLATION OF HISTONE AND NON-HISTONE PROTEINS ALTERS GENE EXPRESSION AND INDUCES A HOST OF CELLULAR EFFECTS. THE ACETYLATION PROCESS IS HOMEOSTATICALLY BALANCED BY TWO GROUPS OF CELLULAR ENZYMES, HISTONE ACETYLTRANSFERASES (HATS) AND HISTONE DEACETYLASES (HDACS). HAT ACTIVITY RELAXES THE STRUCTURE OF THE HUMAN CHROMATIN, RENDERING IT TRANSCRIPTIONALLY ACTIVE, THEREBY INCREASING GENE EXPRESSION. IN CONTRAST, HDAC ACTIVITY LEADS TO GENE SILENCING. THE ENZYMATIC BALANCE CAN BE 'TIPPED' BY HISTONE DEACETYLASE INHIBITORS (HDACI), LEADING TO AN ACCUMULATION OF ACETYLATED PROTEINS, WHICH SUBSEQUENTLY MODIFY CELLULAR PROCESSES INCLUDING STEM CELL DIFFERENTIATION, CELL CYCLE, APOPTOSIS, GENE EXPRESSION, AND ANGIOGENESIS. THERE IS A VARIETY OF NATURAL AND SYNTHETIC HDACI AVAILABLE, AND THEIR PLEIOTROPIC EFFECTS HAVE CONTRIBUTED TO DIVERSE CLINICAL APPLICATIONS, NOT ONLY IN CANCER BUT ALSO IN NON-CANCER AREAS, SUCH AS CHRONIC INFLAMMATORY DISEASE, BONE ENGINEERING, AND NEURODEGENERATIVE DISEASE. INDEED, IT APPEARS THAT HDACI-MODULATED EFFECTS MAY DIFFER BETWEEN 'NORMAL' AND TRANSFORMED CELLS, PARTICULARLY WITH REGARD TO REACTIVE OXYGEN SPECIES ACCUMULATION, APOPTOSIS, PROLIFERATION, AND CELL CYCLE ARREST. THE POTENTIAL BENEFICIAL EFFECTS OF HDACI FOR HEALTH, RESULTING FROM THEIR ABILITY TO REGULATE GLOBAL GENE EXPRESSION BY EPIGENETIC MODIFICATION OF DNA-ASSOCIATED PROTEINS, ALSO OFFER POTENTIAL FOR APPLICATION WITHIN RESTORATIVE DENTISTRY, WHERE THEY MAY PROMOTE DENTAL TISSUE REGENERATION FOLLOWING PULPAL DAMAGE. 2011 6 3197 32 HDAC INHIBITORS: TARGETS FOR TUMOR THERAPY, IMMUNE MODULATION AND LUNG DISEASES. HISTONE DEACETYLASES (HDACS) ARE ENZYMES THAT PLAY A KEY ROLE IN THE EPIGENETIC REGULATION OF GENE EXPRESSION BY REMODELING CHROMATIN. INHIBITION OF HDACS IS A PROSPECTIVE THERAPEUTIC APPROACH FOR REVERSING EPIGENETIC ALTERATION IN SEVERAL DISEASES. IN PRECLINICAL RESEARCH, NUMEROUS TYPES OF HDAC INHIBITORS WERE DISCOVERED TO EXHIBIT POWERFUL AND SELECTIVE ANTICANCER PROPERTIES. HOWEVER, SUCH RESEARCH HAS REVEALED THAT THE EFFECTS OF HDAC INHIBITORS MAY BE FAR BROADER AND MORE INTRICATE THAN PREVIOUSLY THOUGHT. THIS REVIEW WILL PROVIDE INSIGHT INTO THE HDAC INHIBITORS AND THEIR MECHANISM OF ACTION WITH SPECIAL EMPHASIS ON THE SIGNIFICANCE OF HDAC INHIBITORS IN THE TREATMENT OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE AND LUNG CANCER. NANOCARRIER-MEDIATED HDAC INHIBITOR DELIVERY AND NEW APPROACHES FOR TARGETING HDACS ARE ALSO DISCUSSED. 2022 7 3343 32 HISTONE DEACETYLASES (HDAC) IN PHYSIOLOGICAL AND PATHOLOGICAL BONE REMODELLING. HISTONE DEACETYLASES (HDACS)(2) PLAY IMPORTANT ROLES IN THE EPIGENETIC REGULATION OF GENE EXPRESSION IN CELLS AND ARE EMERGING THERAPEUTIC TARGETS FOR TREATING A WIDE RANGE OF DISEASES. HDAC INHIBITORS (HDACI)(3) THAT ACT ON MULTIPLE HDAC ENZYMES HAVE BEEN USED CLINICALLY TO TREAT A NUMBER OF SOLID AND HEMATOLOGICAL MALIGNANCIES. HDACI ARE ALSO CURRENTLY BEING STUDIED FOR THEIR EFFICACY IN NON-MALIGNANT DISEASES, INCLUDING PATHOLOGIC BONE LOSS, BUT THIS HAS NECESSITATED A BETTER UNDERSTANDING OF THE ROLES OF INDIVIDUAL HDAC ENZYMES, PARTICULARLY THE ELEVEN ZINC-CONTAINING ISOZYMES. SELECTIVE ISOZYME-SPECIFIC INHIBITORS CURRENTLY BEING DEVELOPED AGAINST CLASS I HDACS (1, 2, 3 AND 8) AND CLASS II HDACS (4, 5, 6, 7, 9 AND 10) WILL BE VALUABLE TOOLS FOR ELUCIDATING THE ROLES PLAYED BY INDIVIDUAL HDACS IN DIFFERENT PHYSIOLOGICAL AND PATHOLOGICAL SETTINGS. ISOZYME-SPECIFIC HDACI PROMISE TO HAVE GREATER EFFICACY AND REDUCED SIDE EFFECTS, AS REQUIRED FOR TREATING CHRONIC DISEASE OVER EXTENDED PERIODS OF TIME. THIS ARTICLE REVIEWS THE CURRENT UNDERSTANDING OF ROLES FOR INDIVIDUAL HDAC ISOZYMES AND EFFECTS OF HDACI ON BONE CELLS, (OSTEOBLASTS, OSTEOCLASTS AND OSTEOCYTES), IN RELATION TO BONE REMODELLING IN CONDITIONS CHARACTERISED BY PATHOLOGICAL BONE LOSS, INCLUDING PERIODONTITIS, RHEUMATOID ARTHRITIS AND MYELOMA BONE DISEASE. 2017 8 1103 36 COMBINED DUAL EFFECT OF MODULATION OF HUMAN NEUTROPHILS' OXIDATIVE BURST AND INHIBITION OF COLON CANCER CELLS PROLIFERATION BY HYDROXYCINNAMIC ACID DERIVATIVES. COLON CANCER IS ONE OF THE MOST INCIDENT CANCERS IN THE WESTERN WORLD. WHILE BOTH GENETIC AND EPIGENETIC FACTORS MAY CONTRIBUTE TO THE DEVELOPMENT OF COLON CANCER, IT IS KNOWN THAT CHRONIC INFLAMMATION ASSOCIATED TO EXCESSIVE PRODUCTION OF REACTIVE OXYGEN AND NITROGEN SPECIES BY PHAGOCYTES MAY ULTIMATELY INITIATE THE MULTISTEP PROCESS OF COLON CANCER DEVELOPMENT. PHENOLIC COMPOUNDS, WHICH REVEAL ANTIOXIDANT AND ANTIPROLIFERATIVE ACTIVITIES IN COLON CANCER CELLS, CAN BE A GOOD APPROACH TO SURPASS THIS PROBLEM. IN THIS WORK, HYDROXYCINNAMIC AMIDES AND THE RESPECTIVE ACID PRECURSORS WERE TESTED IN VITRO FOR THEIR CAPACITY TO MODULATE HUMAN NEUTROPHILS' OXIDATIVE BURST AND SIMULTANEOUSLY TO INHIBIT GROWTH OF COLON CANCER CELLS. A PHENOLIC AMIDE DERIVATIVE, CAFFEIC ACID HEXYLAMIDE (CAHA) (4) WAS FOUND TO BE THE MOST ACTIVE COMPOUND IN BOTH ASSAYS, INHIBITING HUMAN NEUTROPHILS' OXIDATIVE BURST, RESTRAINING THE INFLAMMATORY PROCESS, INHIBITING GROWTH OF COLON CANCER CELLS AND TRIGGERING MITOCHONDRIAL DYSFUNCTION THAT LEADS CANCER CELLS TO APOPTOSIS. ALTOGETHER, THESE ACHIEVEMENTS CAN CONTRIBUTE TO THE UNDERSTANDING OF THE RELATIONSHIP BETWEEN ANTIOXIDANT AND ANTICANCER ACTIVITIES AND BASED ON THE STRUCTURE-ACTIVITY RELATIONSHIPS (SAR) ESTABLISHED CAN BE THE STARTING POINT TO FIND MORE EFFECTIVE PHENOLIC COMPOUNDS AS ANTICANCER AGENTS. 2016 9 5561 42 ROLE OF HISTONE DEACETYLASES IN MONOCYTE FUNCTION IN HEALTH AND CHRONIC INFLAMMATORY DISEASES. HISTONE DEACETYLASES (HDACS) ARE A FAMILY OF 18 MEMBERS THAT PARTICIPATE IN THE EPIGENETIC REGULATION OF GENE EXPRESSION. IN ADDITION TO HISTONES, SOME HDACS ALSO DEACETYLATE TRANSCRIPTION FACTORS AND SPECIFIC CYTOPLASMIC PROTEINS.MONOCYTES, AS PART OF THE INNATE IMMUNE SYSTEM, MAINTAIN TISSUE HOMEOSTASIS AND HELP FIGHT INFECTIONS AND CANCER. IN THESE CELLS, HDACS ARE INVOLVED IN MULTIPLE PROCESSES INCLUDING PROLIFERATION, MIGRATION, DIFFERENTIATION, INFLAMMATORY RESPONSE, INFECTIONS, AND TUMORIGENESIS. HERE, A SYSTEMATIC DESCRIPTION OF THE ROLE THAT MOST HDACS PLAY IN THESE FUNCTIONS IS REVIEWED. SPECIFICALLY, SOME HDACS INDUCE A PRO-INFLAMMATORY RESPONSE AND PLAY MAJOR ROLES IN HOST DEFENSE. CONVERSELY, OTHER HDACS REPROGRAM MONOCYTES AND MACROPHAGES TOWARDS AN IMMUNOSUPPRESSIVE PHENOTYPE. THE RIGHT BALANCE BETWEEN BOTH TYPES HELPS MONOCYTES TO RESPOND CORRECTLY TO THE DIFFERENT PHYSIOLOGICAL/PATHOLOGICAL STIMULI. HOWEVER, ABERRANT EXPRESSIONS OR ACTIVITIES OF SPECIFIC HDACS ARE ASSOCIATED WITH AUTOIMMUNE DISEASES ALONG WITH OTHER CHRONIC INFLAMMATORY DISEASES, INFECTIONS, OR CANCER.THIS PAPER CRITICALLY REVIEWS THE INTERESTING AND EXTENSIVE KNOWLEDGE REGARDING THE ROLE OF SOME HDACS IN THESE PATHOLOGIES. IT ALSO SHOWS THAT AS YET, VERY LITTLE PROGRESS HAS BEEN MADE TOWARD THE GOAL OF FINDING EFFECTIVE HDAC-TARGETED THERAPIES. HOWEVER, GIVEN THEIR OBVIOUS POTENTIAL, WE CONCLUDE THAT IT IS WORTH THE EFFORT TO DEVELOP MONOCYTE-SPECIFIC DRUGS THAT SELECTIVELY TARGET HDAC SUBTYPES WITH THE AIM OF FINDING EFFECTIVE TREATMENTS FOR DISEASES IN WHICH OUR INNATE IMMUNE SYSTEM IS INVOLVED. 2021 10 6061 30 THE DEVELOPMENT PROSPECTION OF HDAC INHIBITORS AS A POTENTIAL THERAPEUTIC DIRECTION IN ALZHEIMER'S DISEASE. ALZHEIMER'S DISEASE (AD) IS A CHRONIC NEURODEGENERATIVE DISEASE, WHICH IS ASSOCIATED WITH LEARNING AND MEMORY IMPAIRMENT IN THE ELDERLY. RECENT STUDIES HAVE FOUND THAT TREATING AD IN THE WAY OF CHROMATIN REMODELING VIA HISTONE ACETYLATION IS A PROMISING THERAPEUTIC REGIMEN. IN A NUMBER OF RECENT STUDIES, INHIBITORS OF HISTONE DEACETYLASE (HDACS) HAVE BEEN FOUND TO BE A NOVEL PROMISING THERAPEUTIC AGENTS FOR NEUROLOGICAL DISORDERS, PARTICULARLY FOR AD AND OTHER NEURODEGENERATIVE DISEASES. ALTHOUGH HDAC INHIBITORS HAVE THE ABILITY TO AMELIORATE COGNITIVE IMPAIRMENT, SUCCESSFUL TREATMENTS IN THE CLASSIC AD ANIMAL MODEL ARE RARELY TRANSLATED INTO CLINICAL TRIALS. AS FOR THE REDUCTION OF UNWANTED SIDE EFFECTS, THE DEVELOPMENT OF HDAC INHIBITORS WITH INCREASED ISOFORM SELECTIVITY OR SEEKING OTHER DIRECTIONS IS A KEY ISSUE THAT NEEDS TO BE ADDRESSED. THE REVIEW FOCUSED ON LITERATURES ON EPIGENETIC MECHANISMS IN RECENT YEARS, ESPECIALLY ON HISTONE ACETYLATION IN TERMS OF THE ENHANCEMENT OF SPECIFICITY, EFFICACY AND AVOIDING SIDE EFFECTS FOR TREATING AD. 2017 11 3335 24 HISTONE DEACETYLASE INHIBITORS FOR CARDIOVASCULAR CONDITIONS AND HEALTHY LONGEVITY. HISTONE DEACETYLASE INHIBITORS (HDACI) REGULATE GENE EXPRESSION VIA EPIGENETIC MECHANISMS. ACCUMULATING EVIDENCE SUGGESTS THAT HDACI EXERT ANTIPROLIFERATIVE, ANTIOXIDANT, ANTINEOPLASTIC, AND PROAPOPTOTIC EFFECTS THROUGH EPIGENETIC MECHANISMS. FURTHERMORE, HDACI ALSO EXERT ANTITHROMBOTIC AND ANTIFIBROTIC EFFECTS THROUGH REGULATION OF THROMBOTIC AND FIBROTIC TRANSDUCTION MECHANISMS. ONE OF THE OLDEST HDACI IS VALPROIC ACID, WHICH WAS FIRST SYNTHESISED IN 1882. AFTER THE DISCOVERY OF ITS ANTICONVULSANT PROPERTIES FOR THE TREATMENT OF EPILEPSY, THE USE OF VALPROIC ACID WAS EXTENDED TO OTHER CONDITIONS, SUCH AS BIPOLAR DISORDER AND MIGRAINE. GIVEN THE ACCUMULATING EVIDENCE SUPPORTING THE ROLE OF HDACI IN THE TREATMENT OF MULTIPLE MEDICAL CONDITIONS BEYOND EPILEPSY, THE INTEREST IN NOVEL POTENTIAL INDICATIONS FOR HDACI HAS BEEN RENEWED. CONSIDERING THE PLEOTROPIC EPIGENETIC EFFECTS OF HDACI, FUTURE STUDIES COULD ASSESS THEIR EFFICACY AND SAFETY FOR CARDIOVASCULAR DISEASE PREVENTION AND TREATMENT; TREATMENT OF VENOUS THROMBOSIS, ALZHEIMER'S DISEASE, AUTOIMMUNE AND PROINFLAMMATORY CONDITIONS, CHRONIC THROMBOEMBOLIC PULMONARY HYPERTENSION, AND PULMONARY ARTERIAL HYPERTENSION; AND AS A COADJUVANT THERAPY FOR CANCER. ADEQUATELY DESIGNED AND POWERED CLINICAL TRIALS ARE REQUIRED TO ASSESS THE EFFICACY AND SAFETY OF HDACI BEFORE THEIR CLINICAL REPURPOSING. 2021 12 5947 31 TARGETING THE EPIGENOME: SCREENING BIOACTIVE COMPOUNDS THAT REGULATE HISTONE DEACETYLASE ACTIVITY. SCOPE: NUTRIGENOMICS IS A RAPIDLY EXPANDING FIELD THAT ELUCIDATES THE LINK BETWEEN DIET-GENOME INTERACTIONS. RECENT EVIDENCE DEMONSTRATES THAT REGULATION OF THE EPIGENOME, AND IN PARTICULAR INHIBITION OF HISTONE DEACETYLASES (HDACS), IMPACT PATHOGENETIC MECHANISMS INVOLVED IN CHRONIC DISEASE. FEW STUDIES, TO DATE, HAVE SCREENED LIBRARIES OF BIOACTIVE COMPOUNDS THAT ACT AS EPIGENETIC MODIFIERS. THIS STUDY SCREENED A LIBRARY OF 131 NATURAL COMPOUNDS TO DETERMINE BIOACTIVE COMPOUNDS THAT INHIBIT ZN-DEPENDENT HDAC ACTIVITY. METHODS AND RESULTS: USING CLASS-SPECIFIC HDAC SUBSTRATES, WE SCREENED 131 NATURAL COMPOUNDS FOR HDAC ACTIVITY IN BOVINE CARDIAC TISSUE. FROM THIS SCREEN, WE IDENTIFIED 18 BIOACTIVE COMPOUND HDAC INHIBITORS. USING OUR CLASS-SPECIFIC HDAC SUBSTRATES, WE NEXT SCREENED THESE 18 BIOACTIVE COMPOUNDS AGAINST RECOMBINANT HDAC PROTEINS. CONSISTENT WITH INHIBITION OF HDAC ACTIVITY, THESE COMPOUNDS WERE CAPABLE OF INHIBITING ACTIVITY OF INDIVIDUAL HDAC ISOFORMS. LASTLY, WE REPORT THAT TREATMENT OF H9C2 CARDIAC MYOBLASTS WITH BIOACTIVE HDAC INHIBITORS WAS SUFFICIENT TO INCREASE LYSINE ACETYLATION AS ASSESSED VIA IMMUNOBLOT. CONCLUSION: THIS STUDY PROVIDED THE FIRST STEP IN IDENTIFYING MULTIPLE BIOACTIVE COMPOUND HDAC INHIBITORS. TAKEN TOGETHER, THIS REPORT SETS THE STAGE FOR FUTURE EXPLORATION OF THESE BIOACTIVE COMPOUNDS AS EPIGENETIC REGULATORS TO POTENTIALLY AMELIORATE CHRONIC DISEASE. 2017 13 2254 29 EPIGENETIC MODULATION: RESEARCH PROGRESS ON HISTONE ACETYLATION LEVELS IN MAJOR DEPRESSIVE DISORDERS. DEPRESSION IS A SERIOUS MENTAL ILLNESS AND A PREVALENT CONDITION WITH MULTIPLE AETIOLOGIES. THE IMPACT OF THE CURRENT THERAPEUTIC STRATEGIES IS LIMITED AND THE PATHOGENESIS OF THE ILLNESS IS NOT WELL UNDERSTOOD. ACCORDING TO PREVIOUS STUDIES, DEPRESSION ONSET IS INFLUENCED BY A VARIETY OF ENVIRONMENTAL AND GENETIC FACTORS, INCLUDING CHRONIC STRESS, ABERRANT CHANGES IN GENE EXPRESSION, AND HEREDITARY PREDISPOSITION. TRANSCRIPTIONAL REGULATION IN EUKARYOTES IS CLOSELY RELATED TO CHROMOSOME PACKING AND IS CONTROLLED BY HISTONE POST-TRANSLATIONAL MODIFICATIONS. THE DEVELOPMENT OF NEW ANTIDEPRESSANTS MAY PROCEED ALONG A NEW PATH WITH MEDICATIONS THAT TARGET EPIGENETICS. HISTONE DEACETYLASE INHIBITORS (HDACIS) ARE A CLASS OF COMPOUNDS THAT INTERFERE WITH THE FUNCTION OF HISTONE DEACETYLASES (HDACS). THIS REVIEW EXPLORES THE RELATIONSHIP BETWEEN HDACS AND DEPRESSION AND FOCUSES ON THE CURRENT KNOWLEDGE ON THEIR REGULATORY MECHANISM IN DEPRESSION AND THE POTENTIAL THERAPEUTIC USE OF HDACIS WITH ANTIDEPRESSANT EFFICACY IN PRECLINICAL RESEARCH. FUTURE RESEARCH ON INHIBITORS IS ALSO PROPOSED AND DISCUSSED. 2023 14 3333 35 HISTONE DEACETYLASE INHIBITORS AND DIABETIC KIDNEY DISEASE. DESPITE RECENT CLINICAL TRIAL ADVANCES AND IMPROVEMENTS IN CLINICAL CARE, KIDNEY DISEASE DUE TO DIABETES REMAINS THE MOST COMMON CAUSE OF CHRONIC KIDNEY FAILURE WORLDWIDE. IN THE SEARCH FOR NEW TREATMENTS, RECENT ATTENTIONS HAVE TURNED TO DRUG REPURPOSING OPPORTUNITIES, INCLUDING STUDY OF THE HISTONE DEACETYLASE (HDAC) INHIBITOR CLASS OF AGENTS. HDACS ARE A GROUP OF ENZYMES THAT REMOVE FUNCTIONAL ACETYL GROUPS FROM HISTONE AND NON-HISTONE PROTEINS AND THEY CAN AFFECT CELLULAR FUNCTION THROUGH BOTH EPIGENETIC AND NON-EPIGENETIC MEANS. OVER THE PAST DECADE, SEVERAL HDAC INHIBITORS HAVE BEEN ADOPTED INTO CLINICAL PRACTICE, PRIMARILY FOR THE TREATMENT OF HEMATOLOGICAL MALIGNANCY, WHEREAS OTHER EXISTING THERAPIES (FOR INSTANCE VALPROATE) HAVE BEEN FOUND TO HAVE HDAC INHIBITORY EFFECTS. HERE WE REVIEW THE CURRENT HDAC INHIBITORS IN THE CLINIC AND UNDER DEVELOPMENT; THE LITERATURE EVIDENCE SUPPORTING THE RENOPROTECTIVE EFFECTS OF HDAC INHIBITORS IN EXPERIMENTAL DIABETIC KIDNEY DISEASE; AND THE ADVERSE EFFECT PROFILES THAT MAY PREVENT EXISTING THERAPIES FROM ENTERING THE CLINIC FOR THIS INDICATION. WHEREAS RECENT RESEARCH EFFORTS HAVE SHED LIGHT ON THE FUNDAMENTAL ACTIONS OF HDACS IN THE DIABETIC KIDNEY, WHETHER THESE EFFORTS WILL TRANSLATE INTO NOVEL THERAPIES FOR PATIENTS WILL REQUIRE MORE SPECIFIC AND BETTER-TOLERATED THERAPIES. 2018 15 3855 23 IS THERE ANY THERAPEUTIC VALUE FOR THE USE OF HISTONE DEACETYLASE INHIBITORS FOR CHRONIC PAIN? CHRONIC PAIN IS A COMPLEX CLINICAL CONDITION THAT REDUCES THE QUALITY OF LIFE FOR BILLIONS OF PEOPLE. IN RECENT YEARS, THE ROLE OF EPIGENETIC MODULATION IN THE CONTROL OF LONG-TERM NEURONAL PLASTICITY HAS ATTRACTED THE ATTENTION OF PAIN RESEARCHERS. THE EPIGENETIC MECHANISMS INCLUDE COVALENT MODIFICATIONS OF DNA AND/OR HISTONE PROTEINS. MOUNTING EVIDENCE SUGGESTS THAT THE ACTIVITY OF HISTONE DEACETYLASES (HDACS) AND LEVELS OF HISTONE ACETYLATION ARE DYNAMIC AND THAT THESE ENZYMES MODULATE PAIN-RELATED SYNAPTIC PLASTICITY. THEREFORE, HDACS PLAY ESSENTIAL ROLES IN CHRONIC PAIN DEVELOPMENT AND MAINTENANCE. IN THIS MINI REVIEW, WE WILL DISCUSS THE ROLE OF HDACS IN THE PATHOGENESIS OF CHRONIC PAIN AND WILL CONSIDER THE THERAPEUTIC VALUE OF HDAC INHIBITORS IN TREATING CHRONIC PAIN. 2016 16 2119 23 EPIGENETIC HISTONE MODIFICATION REGULATES DEVELOPMENTAL LEAD EXPOSURE INDUCED HYPERACTIVITY IN RATS. LEAD (PB) EXPOSURE WAS COMMONLY CONSIDERED AS A HIGH ENVIRONMENTAL RISK FACTOR FOR THE DEVELOPMENT OF ATTENTION-DEFICIT/HYPERACTIVITY DISORDER (ADHD). HOWEVER, THE MOLECULAR BASIS OF THIS PATHOLOGICAL PROCESS STILL REMAINS ELUSIVE. IN LIGHT OF THE ROLE OF EPIGENETICS IN MODULATING THE NEUROLOGICAL DISEASE AND THE CAUSATIVE ENVIRONMENT, THE ALTERATIONS OF HISTONE MODIFICATIONS IN THE HIPPOCAMPUS OF RATS EXPOSED BY VARIOUS DOSES OF LEAD, ALONG WITH CONCOMITANT BEHAVIORAL DEFICITS, WERE INVESTIGATED IN THIS STUDY. ACCORDING TO THE FREE AND FORCED OPEN FIELD TEST, THERE SHOWED THAT IN A DOSAGE-DEPENDENT MANNER, LEAD EXPOSURE COULD RESULT IN THE INCREASED LOCOMOTOR ACTIVITY OF RATS, THAT IS, HYPERACTIVITY: A SUBTYPE OF ADHD. WESTERN BLOTTING ASSAYS REVEALED THAT THE LEVELS OF HISTONE ACETYLATION INCREASED SIGNIFICANTLY IN THE HIPPOCAMPUS BY CHRONIC LEAD EXPOSURE, WHILE NO DRAMATIC CHANGES WERE DETECTED IN TERMS OF EXPRESSION YIELDS OF ADHD-RELATED DOPAMINERGIC PROTEINS, INDICATING THAT HISTONE ACETYLATION PLAYS ESSENTIAL ROLES IN THIS TOXICANT-INVOLVED PATHOGENESIS. IN ADDITION, THE INCREASED LEVEL OF HISTONE ACETYLATION MIGHT BE ATTRIBUTED TO THE ENZYMATIC ACTIVITY OF P300, A TYPICAL HISTONE ACETYLTRANSFERASE, AS THE TRANSCRIPTIONAL LEVEL OF P300 WAS SIGNIFICANTLY INCREASED UPON HIGHER-DOSE PB EXPOSURE. IN SUMMARY, THIS STUDY FIRST DISCOVERED THE EPIGENETIC MECHANISM BRIDGING THE ENVIRONMENTAL INFLUENCE (PB) AND THE DISEASE ITSELF (ADHD) IN THE HISTONE MODIFICATION LEVEL, PAVING THE WAY FOR THE COMPREHENSIVE UNDERSTANDING OF ADHD'S ETIOLOGY AND IN FURTHER STEPS, ESTABLISHING THE THERAPY STRATEGY OF THIS WIDESPREAD NEUROLOGICAL DISORDER. 2014 17 2493 41 EPIGENETICS AND CHROMATIN REMODELING PLAY A ROLE IN LUNG DISEASE. EPIGENETICS IS DEFINED AS HERITABLE CHANGES THAT AFFECT GENE EXPRESSION WITHOUT ALTERING THE DNA SEQUENCE. EPIGENETIC REGULATION OF GENE EXPRESSION IS FACILITATED THROUGH DIFFERENT MECHANISMS SUCH AS DNA METHYLATION, HISTONE MODIFICATIONS AND RNA-ASSOCIATED SILENCING BY SMALL NON-CODING RNAS. ALL THESE MECHANISMS ARE CRUCIAL FOR NORMAL DEVELOPMENT, DIFFERENTIATION AND TISSUE-SPECIFIC GENE EXPRESSION. THESE THREE SYSTEMS INTERACT AND STABILIZE ONE ANOTHER AND CAN INITIATE AND SUSTAIN EPIGENETIC SILENCING, THUS DETERMINING HERITABLE CHANGES IN GENE EXPRESSION. HISTONE ACETYLATION REGULATES DIVERSE CELLULAR FUNCTIONS INCLUDING INFLAMMATORY GENE EXPRESSION, DNA REPAIR AND CELL PROLIFERATION. TRANSCRIPTIONAL COACTIVATORS POSSESS INTRINSIC HISTONE ACETYLTRANSFERASE ACTIVITY AND THIS ACTIVITY DRIVES INFLAMMATORY GENE EXPRESSION. ELEVEN CLASSICAL HISTONE DEACETYLASES (HDACS) ACT TO REGULATE THE EXPRESSION OF DISTINCT SUBSETS OF INFLAMMATORY/IMMUNE GENES. THUS, LOSS OF HDAC ACTIVITY OR THE PRESENCE OF HDAC INHIBITORS CAN FURTHER ENHANCE INFLAMMATORY GENE EXPRESSION BY PRODUCING A GENE-SPECIFIC CHANGE IN HAT ACTIVITY. FOR EXAMPLE, HDAC2 EXPRESSION AND ACTIVITY ARE REDUCED IN LUNG MACROPHAGES, BIOPSY SPECIMENS, AND BLOOD CELLS FROM PATIENTS WITH SEVERE ASTHMA AND SMOKING ASTHMATICS, AS WELL AS IN PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). THIS MAY ACCOUNT, AT LEAST IN PART, FOR THE ENHANCED INFLAMMATION AND REDUCED STEROID RESPONSIVENESS SEEN IN THESE PATIENTS. OTHER PROTEINS, PARTICULARLY TRANSCRIPTION FACTORS, ARE ALSO ACETYLATED AND ARE TARGETS FOR DEACETYLATION BY HDACS AND SIRTUINS, A RELATED FAMILY OF 7 PREDOMINANTLY PROTEIN DEACETYLASES. THUS THE ACETYLATION/DEACETYLATION STATUS OF NF-KAPPAB AND THE GLUCOCORTICOID RECEPTOR CAN ALSO AFFECT THE OVERALL EXPRESSION PATTERN OF INFLAMMATORY GENES AND REGULATE THE INFLAMMATORY RESPONSE. UNDERSTANDING AND TARGETING SPECIFIC ENZYMES INVOLVED IN THIS PROCESS MIGHT LEAD TO NEW THERAPEUTIC AGENTS, PARTICULARLY IN SITUATIONS IN WHICH CURRENT ANTI-INFLAMMATORY THERAPIES ARE SUBOPTIMAL. 2011 18 5550 34 ROLE OF EPIGENETICS IN INFLAMMATION-ASSOCIATED DISEASES. THERE IS CONSIDERABLE EVIDENCE SUGGESTING THAT EPIGENETIC MECHANISMS MAY MEDIATE DEVELOPMENT OF CHRONIC INFLAMMATION BY MODULATING THE EXPRESSION OF PRO-INFLAMMATORY CYTOKINE TNF-ALPHA, INTERLEUKINS, TUMOR SUPPRESSOR GENES, ONCOGENES AND AUTOCRINE AND PARACRINE ACTIVATION OF THE TRANSCRIPTION FACTOR NF-KAPPAB. THESE MOLECULES ARE CONSTITUTIVELY PRODUCED BY A VARIETY OF CELLS UNDER CHRONIC INFLAMMATORY CONDITIONS, WHICH IN TURN LEADS TO THE DEVELOPMENT OF MAJOR DISEASES SUCH AS AUTOIMMUNE DISORDERS, CHRONIC OBSTRUCTIVE PULMONARY DISEASES, NEURODEGENERATIVE DISEASES AND CANCER. DISTINCT OR GLOBAL CHANGES IN THE EPIGENETIC LANDSCAPE ARE HALLMARKS OF CHRONIC INFLAMMATION DRIVEN DISEASES. EPIGENETICS INCLUDE CHANGES TO DISTINCT MARKERS ON THE GENOME AND ASSOCIATED CELLULAR TRANSCRIPTIONAL MACHINERY THAT ARE COPIED DURING CELL DIVISION (MITOSIS AND MEIOSIS). THESE CHANGES APPEAR FOR A SHORT SPAN OF TIME AND THEY NECESSARILY DO NOT MAKE PERMANENT CHANGES TO THE PRIMARY DNA SEQUENCE ITSELF. HOWEVER, THE MOST FREQUENTLY OBSERVED EPIGENETIC CHANGES INCLUDE ABERRANT DNA METHYLATION, AND HISTONE ACETYLATION AND DEACETYLATION. IN THIS CHAPTER, WE FOCUS ON PRO-INFLAMMATORY MOLECULES THAT ARE REGULATED BY ENZYMES INVOLVED IN EPIGENETIC MODIFICATIONS SUCH AS ARGININE AND LYSINE METHYL TRANSFERASES, DNA METHYLTRANSFERASE, HISTONE ACETYLTRANSFERASES AND HISTONE DEACETYLASES AND THEIR ROLE IN INFLAMMATION DRIVEN DISEASES. AGENTS THAT MODULATE OR INHIBIT THESE EPIGENETIC MODIFICATIONS, SUCH AS HAT OR HDAC INHIBITORS HAVE SHOWN GREAT POTENTIAL IN INHIBITING THE PROGRESSION OF THESE DISEASES. GIVEN THE PLASTICITY OF THESE EPIGENETIC CHANGES AND THEIR READINESS TO RESPOND TO INTERVENTION BY SMALL MOLECULE INHIBITORS, THERE IS A TREMENDOUS POTENTIAL FOR THE DEVELOPMENT OF NOVEL THERAPEUTICS THAT WILL SERVE AS DIRECT OR ADJUVANT THERAPEUTIC COMPOUNDS IN THE TREATMENT OF THESE DISEASES. 2013 19 1688 32 DUAL BET/HDAC INHIBITION TO RELIEVE NEUROPATHIC PAIN: RECENT ADVANCES, PERSPECTIVES, AND FUTURE OPPORTUNITIES. DESPITE THE INTENSE RESEARCH ON DEVELOPING NEW THERAPIES FOR NEUROPATHIC PAIN STATES, AVAILABLE TREATMENTS HAVE LIMITED EFFICACY AND UNFAVORABLE SAFETY PROFILES. EPIGENETIC ALTERATIONS HAVE A GREAT INFLUENCE ON THE DEVELOPMENT OF CANCER AND NEUROLOGICAL DISEASES, AS WELL AS NEUROPATHIC PAIN. HISTONE ACETYLATION HAS PREVAILED AS ONE OF THE WELL INVESTIGATED EPIGENETIC MODIFICATIONS IN THESE DISEASES. ALTERED SPINAL ACTIVITY OF HISTONE DEACETYLASE (HDAC) AND BROMO AND EXTRA TERMINAL DOMAIN (BET) HAVE BEEN DESCRIBED IN NEUROPATHIC PAIN MODELS AND RESTORATION OF THESE ABERRANT EPIGENETIC MODIFICATIONS SHOWED PAIN-RELIEVING ACTIVITY. OVER THE LAST DECADES HDACS AND BETS HAVE BEEN THE FOCUS OF DRUG DISCOVERY STUDIES, LEADING TO THE DEVELOPMENT OF NUMEROUS SMALL-MOLECULE INHIBITORS. CLINICAL TRIALS TO EVALUATE THEIR ANTICANCER ACTIVITY SHOWED GOOD EFFICACY BUT RAISED TOXICITY CONCERNS THAT LIMITED TRANSLATION TO THE CLINIC. TO MAXIMIZE ACTIVITY AND MINIMIZE TOXICITY, THESE COMPOUNDS CAN BE APPLIED IN COMBINATION OF SUB-MAXIMAL DOSES TO PRODUCE ADDITIVE OR SYNERGISTIC INTERACTIONS (COMBINATION THERAPY). RECENTLY, OF PARTICULAR INTEREST, DUAL BET/HDAC INHIBITORS (MULTI-TARGET DRUGS) HAVE BEEN DEVELOPED TO ASSURE SIMULTANEOUS MODULATION OF BET AND HDAC ACTIVITY BY A SINGLE MOLECULE. THIS REVIEW WILL SUMMARIZE THE MOST RECENT ADVANCES WITH THESE STRATEGIES, DESCRIBING ADVANTAGES AND LIMITATIONS OF SINGLE DRUG TREATMENT VS COMBINATION REGIMENS. THIS REVIEW WILL ALSO PROVIDE A FOCUS ON DUAL BET/HDAC DRUG DISCOVERY INVESTIGATIONS AS FUTURE THERAPEUTIC OPPORTUNITY FOR HUMAN THERAPY OF NEUROPATHIC PAIN. 2021 20 1326 25 DEPLETION OF NUCLEAR HISTONE H2A VARIANTS IS ASSOCIATED WITH CHRONIC DNA DAMAGE SIGNALING UPON DRUG-EVOKED SENESCENCE OF HUMAN SOMATIC CELLS. CELLULAR SENESCENCE IS ASSOCIATED WITH GLOBAL CHROMATIN CHANGES, ALTERED GENE EXPRESSION, AND ACTIVATION OF CHRONIC DNA DAMAGE SIGNALING. THESE EVENTS ULTIMATELY LEAD TO MORPHOLOGICAL AND PHYSIOLOGICAL TRANSFORMATIONS IN PRIMARY CELLS. IN THIS STUDY, WE SHOW THAT CHRONIC DNA DAMAGE SIGNALS CAUSED BY GENOTOXIC STRESS IMPACT THE EXPRESSION OF HISTONES H2A FAMILY MEMBERS AND LEAD TO THEIR DEPLETION IN THE NUCLEI OF SENESCENT HUMAN FIBROBLASTS. OUR DATA REINFORCE THE HYPOTHESIS THAT PROGRESSIVE CHROMATIN DESTABILIZATION MAY LEAD TO THE LOSS OF EPIGENETIC INFORMATION AND IMPAIRED CELLULAR FUNCTION ASSOCIATED WITH CHRONIC DNA DAMAGE UPON DRUG-EVOKED SENESCENCE. WE PROPOSE THAT CHANGES IN THE HISTONE BIOSYNTHESIS AND CHROMATIN ASSEMBLY MAY DIRECTLY CONTRIBUTE TO CELLULAR AGING. IN ADDITION, WE ALSO OUTLINE THE METHOD THAT ALLOWS FOR QUANTITATIVE AND UNBIASED MEASUREMENT OF THESE CHANGES. 2012