1 2772 211 EXTRACELLULAR ATP AND NEURODEGENERATION. ATP IS A POTENT SIGNALING MOLECULE ABUNDANTLY PRESENT IN THE CNS. IT ELICITS A WIDE ARRAY OF PHYSIOLOGICAL EFFECTS AND IS REGARDED AS THE PHYLOGENETICALLY MOST ANCIENT EPIGENETIC FACTOR PLAYING CRUCIAL BIOLOGICAL ROLES IN SEVERAL DIFFERENT TISSUES. THESE CAN RANGE FROM NEUROTRANSMISSION, SMOOTH MUSCLE CONTRACTION, CHEMOSENSORY SIGNALING, SECRETION AND VASODILATATION, TO MORE COMPLEX PHENOMENA SUCH AS IMMUNE RESPONSES, PAIN, MALE REPRODUCTION, FERTILIZATION AND EMBRYONIC DEVELOPMENT. ATP IS RELEASED INTO THE EXTRACELLULAR SPACE EITHER EXOCYTOTICALLY OR FROM DAMAGED AND DYING CELLS. IT IS OFTEN CO-RELEASED WITH OTHER NEUROTRANSMITTERS AND IT CAN INTERACT WITH GROWTH FACTORS AT BOTH RECEPTOR- AND/OR SIGNAL TRANSDUCTION-LEVEL. ONCE IN THE EXTRACELLULAR ENVIRONMENT, ATP BINDS TO SPECIFIC RECEPTORS TERMED P2. BASED ON PHARMACOLOGICAL PROFILES, ON SELECTIVITY OF COUPLING TO SECOND-MESSENGER PATHWAYS AND ON MOLECULAR CLONING, TWO MAIN SUBCLASSES WITH MULTIPLE SUBTYPES HAVE BEEN DISTINGUISHED. THEY ARE P2X, I.E. FAST CATION-SELECTIVE RECEPTOR CHANNELS (NA+, K+, CA2+), POSSESSING LOW AFFINITY FOR ATP AND RESPONSIBLE FOR FAST EXCITATORY NEUROTRANSMISSION, AND P2Y, I.E. SLOW G PROTEIN-COUPLED METABOTROPIC RECEPTORS, POSSESSING HIGHER AFFINITY FOR THE LIGAND. IN THE NERVOUS SYSTEM, THEY ARE BROADLY EXPRESSED IN BOTH NEURONS AND GLIAL CELLS AND CAN MEDIATE DUAL EFFECTS: SHORT-TERM SUCH AS NEUROTRANSMISSION, AND LONG-TERM SUCH AS TROPHIC ACTIONS. SINCE MASSIVE EXTRACELLULAR RELEASE OF ATP OFTEN OCCURS AFTER METABOLIC STRESS, BRAIN ISCHEMIA AND TRAUMA, PURINERGIC MECHANISMS ARE ALSO CORRELATED TO AND INVOLVED IN THE ETIOPATHOLOGY OF MANY NEURODEGENERATIVE CONDITIONS. FURTHERMORE, EXTRACELLULAR ATP PER SE IS TOXIC FOR PRIMARY NEURONAL DISSOCIATED AND ORGANOTYPIC CNS CULTURES FROM CORTEX, STRIATUM AND CEREBELLUM AND P2 RECEPTORS CAN MEDIATE AND AGGRAVATE HYPOXIC SIGNALING IN MANY CNS NEURONS. CONVERSELY, SEVERAL P2 RECEPTOR ANTAGONISTS ABOLISH THE CELL DEATH FATE OF PRIMARY NEURONAL CULTURES EXPOSED TO EXCESSIVE GLUTAMATE, SERUM/POTASSIUM DEPRIVATION, HYPOGLYCEMIA AND CHEMICAL HYPOXIA. IN PARALLEL WITH THESE DETRIMENTAL EFFECTS, ALSO TROPHIC FUNCTIONS HAVE BEEN EXTENSIVELY DESCRIBED FOR EXTRACELLULAR PURINES (BOTH FOR NEURONAL AND NON-NEURONAL CELLS), BUT THESE MIGHT EITHER AGGRAVATE OR AMELIORATE THE NORMAL CELLULAR CONDITIONS. IN SUMMARY, EXTRACELLULAR ATP PLAYS A VERY COMPLEX ROLE NOT ONLY IN THE REPAIR, REMODELING AND SURVIVAL OCCURRING IN THE NERVOUS SYSTEM, BUT EVEN IN CELL DEATH AND THIS CAN OCCUR EITHER AFTER NORMAL DEVELOPMENTAL CONDITIONS, AFTER INJURY, OR ACUTE AND CHRONIC DISEASES. 2003 2 4304 42 MICRORNA-223 PROTECTS NEURONS FROM DEGENERATION IN EXPERIMENTAL AUTOIMMUNE ENCEPHALOMYELITIS. MULTIPLE SCLEROSIS IS A CHRONIC INFLAMMATORY, DEMYELINATING, AND NEURODEGENERATIVE DISEASE AFFECTING THE BRAIN, SPINAL CORD AND OPTIC NERVES. NEURONAL DAMAGE IS TRIGGERED BY VARIOUS HARMFUL FACTORS THAT ENGAGE DIVERSE SIGNALLING CASCADES IN NEURONS; THUS, THERAPEUTIC APPROACHES TO PROTECT NEURONS WILL NEED TO FOCUS ON AGENTS THAT CAN TARGET MULTIPLE BIOLOGICAL PROCESSES. WE HAVE THEREFORE FOCUSED OUR ATTENTION ON MICRORNAS: SMALL NON-CODING RNAS THAT PRIMARILY FUNCTION AS POST-TRANSCRIPTIONAL REGULATORS THAT TARGET MESSENGER RNAS AND REPRESS THEIR TRANSLATION INTO PROTEINS. A SINGLE MICRORNA CAN TARGET MANY FUNCTIONALLY RELATED MESSENGER RNAS MAKING MICRORNAS POWERFUL EPIGENETIC REGULATORS. DYSREGULATION OF MICRORNAS HAS BEEN DESCRIBED IN MANY NEURODEGENERATIVE DISEASES INCLUDING MULTIPLE SCLEROSIS. HERE, WE REPORT THAT TWO MICRORNAS, MIR-223-3P AND MIR-27A-3P, ARE UPREGULATED IN NEURONS IN THE EXPERIMENTAL AUTOIMMUNE ENCEPHALOMYELITIS MOUSE MODEL OF CNS INFLAMMATION AND IN GREY MATTER-CONTAINING MULTIPLE SCLEROSIS LESIONS. PRIOR WORK HAS SHOWN PERIPHERAL BLOOD MONONUCLEAR CELL CONDITIONED MEDIA CAUSES SUBLETHAL DEGENERATION OF NEURONS IN CULTURE. WE FIND OVEREXPRESSION OF MIR-27A-3P OR MIR-223-3P PROTECTS DISSOCIATED CORTICAL NEURONS FROM CONDITION MEDIA MEDIATED DEGENERATION. INTRODUCTION OF MIR-223-3P IN VIVO IN MOUSE RETINAL GANGLION CELLS PROTECTS THEIR AXONS FROM DEGENERATION IN EXPERIMENTAL AUTOIMMUNE ENCEPHALOMYELITIS. IN SILICO ANALYSIS REVEALED THAT MESSENGER RNAS INVOLVED IN GLUTAMATE RECEPTOR SIGNALLING ARE ENRICHED AS MIR-27A-3P AND MIR-223-3P TARGETS. WE OBSERVE THAT ANTAGONISM OF NMDA AND AMPA TYPE GLUTAMATE RECEPTORS PROTECTS NEURONS FROM CONDITION MEDIA DEPENDENT DEGENERATION. OUR RESULTS SUGGEST THAT MIR-223-3P AND MIR-27A-3P ARE UPREGULATED IN RESPONSE TO INFLAMMATION TO MEDIATE A COMPENSATORY NEUROPROTECTIVE GENE EXPRESSION PROGRAM THAT DESENSITIZES NEURONS TO GLUTAMATE BY TARGETING MESSENGER RNAS INVOLVED IN GLUTAMATE RECEPTOR SIGNALLING. 2019 3 80 39 A NEW ROLE FOR THE P2Y-LIKE GPR17 RECEPTOR IN THE MODULATION OF MULTIPOTENCY OF OLIGODENDROCYTE PRECURSOR CELLS IN VITRO. OLIGODENDROCYTE PRECURSOR CELLS (OPCS, ALSO CALLED NG2 CELLS) ARE SCATTERED THROUGHOUT BRAIN PARENCHYMA, WHERE THEY FUNCTION AS A RESERVOIR TO REPLACE LOST OR DAMAGED OLIGODENDROCYTES, THE MYELIN-FORMING CELLS. THE HYPOTHESIS THAT, UNDER SOME CIRCUMSTANCES, OPCS CAN ACTUALLY BEHAVE AS MULTIPOTENT CELLS, THUS GENERATING ASTROCYTES AND NEURONS AS WELL, HAS ARISEN FROM SOME IN VITRO AND IN VIVO EVIDENCE, BUT THE MOLECULAR PATHWAYS CONTROLLING THIS ALTERNATIVE FATE OF OPCS ARE NOT FULLY UNDERSTOOD. THEIR IDENTIFICATION WOULD OPEN NEW OPPORTUNITIES FOR NEURONAL REPLACE STRATEGIES, BY FOSTERING THE INTRINSIC ABILITY OF THE BRAIN TO REGENERATE. HERE, WE SHOW THAT THE ANTI-EPILEPTIC EPIGENETIC MODULATOR VALPROIC ACID (VPA) CAN PROMOTE THE GENERATION OF NEW NEURONS FROM NG2(+) OPCS UNDER NEUROGENIC PROTOCOLS IN VITRO, THROUGH THEIR INITIAL DE-DIFFERENTIATION TO A STEM CELL-LIKE PHENOTYPE THAT THEN EVOLVES TO "HYBRID" CELL POPULATION, SHOWING OPC MORPHOLOGY BUT EXPRESSING THE NEURONAL MARKER BETAIII-TUBULIN AND THE GPR17 RECEPTOR, A KEY DETERMINANT IN DRIVING OPC TRANSITION TOWARDS MYELINATING OLIGODENDROCYTES. UNDER THESE CONDITIONS, THE PHARMACOLOGICAL BLOCKADE OF THE P2Y-LIKE RECEPTOR GPR17 BY CANGRELOR, A DRUG RECENTLY APPROVED FOR HUMAN USE, PARTIALLY MIMICS THE EFFECTS MEDIATED BY VPA THUS ACCELERATING CELLS' NEUROGENIC CONVERSION. THESE DATA SHOW A CO-LOCALIZATION BETWEEN NEURONAL MARKERS AND GPR17 IN VITRO, AND SUGGEST THAT, BESIDES ITS INVOLVEMENT IN OLIGODENDROGENESIS, GPR17 CAN DRIVE THE FATE OF NEURAL PRECURSOR CELLS BY INSTRUCTING PRECURSORS TOWARDS THE NEURONAL LINEAGE. BEING A MEMBRANE RECEPTOR, GPR17 REPRESENTS AN IDEAL "DRUGGABLE" TARGET TO BE EXPLOITED FOR INNOVATIVE REGENERATIVE APPROACHES TO ACUTE AND CHRONIC BRAIN DISEASES. 2016 4 2066 34 EPIGENETIC CONTROL OF ION CHANNEL EXPRESSION AND CELL-SPECIFIC SPLICING IN NOCICEPTORS: CHRONIC PAIN MECHANISMS AND POTENTIAL THERAPEUTIC TARGETS. ION CHANNELS UNDERLIE ALL FORMS FOR ELECTRICAL SIGNALING INCLUDING THE TRANSMISSION OF INFORMATION ABOUT HARMFUL EVENTS. VOLTAGE-GATED CALCIUM ION CHANNELS HAVE DUAL FUNCTION, THEY SUPPORT ELECTRICAL SIGNALING AS WELL AS INTRACELLULAR CALCIUM SIGNALING THROUGH EXCITATION-DEPENDENT CALCIUM ENTRY ACROSS THE PLASMA MEMBRANE. MECHANISMS THAT REGULATE ION CHANNEL FORMS AND ACTIONS ARE ESSENTIAL FOR MYRIAD CELL FUNCTIONS AND THESE ARE TARGETED BY DRUGS AND THERAPEUTICS. WHEN DISRUPTED, THE CELLULAR MECHANISMS THAT CONTROL ION CHANNEL ACTIVITY CAN CONTRIBUTE TO DISEASE PATHOPHYSIOLOGY. FOR EXAMPLE, ALTERNATIVE PRE-MRNA SPLICING IS A MAJOR STEP IN DEFINING THE PRECISE COMPOSITION OF THE TRANSCRIPTOME ACROSS DIFFERENT CELL TYPES FROM EARLY CELLULAR DIFFERENTIATION TO PROGRAMMED APOPTOSIS. AN ESTIMATED 30% OF DISEASE-CAUSING MUTATIONS ARE ASSOCIATED WITH ALTERED ALTERNATIVE SPLICING, AND MIS-SPLICING IS A FEATURE OF NUMEROUS HIGHLY PREVALENT DISEASES INCLUDING NEURODEGENERATIVE, CANCER, AND CHRONIC PAIN. HERE WE DISCUSS THE IMPORTANT ROLE OF EPIGENETIC REGULATION OF GENE EXPRESSION AND CELL-SPECIFIC ALTERNATIVE SPLICING OF CALCIUM ION CHANNELS IN NOCICEPTORS, WITH EMPHASIS ON HOW THESE PROCESSES ARE DISRUPTED IN CHRONIC PAIN, THE POTENTIAL THERAPEUTIC BENEFIT OF CORRECTING OR COMPENSATING FOR ABERRANT ION CHANNEL SPLICING IN CHRONIC PAIN. 2021 5 1637 39 DOES DYSREGULATION OF KEY EPIGENETIC AND BIOCHEMICAL PATHWAYS OCCUR IN POSTULATED VASOACTIVE NEUROPEPTIDE AUTOIMMUNE DISORDERS? AUTOIMMUNE DYSFUNCTION OF CERTAIN VASOACTIVE NEUROPEPTIDES (VNS) HAS BEEN POSTULATED AS A CONTRIBUTING CAUSE OF SUDDEN INFANT DEATH SYNDROME (SIDS), CHRONIC FATIGUE SYNDROME (CFS), GULF WAR SYNDROME (GWS) AND OTHER FATIGUE-RELATED DISORDERS. THIS FAMILY OF VNS INCLUDES PITUITARY ADENYLATE CYCLASE ACTIVATING POLYPEPTIDE (PACAP), VASOACTIVE INTESTINAL PEPTIDE (VIP) AND CALCITONIN GENE RELATED PEPTIDE (CGRP). THE POSTULATED MECHANISM IS COMPROMISE OF ADENYLATE CYCLASE ACTIVATION, A VITAL AND UNIQUE STEP IN CYCLIC AMP PRODUCTION FROM ATP, THROUGH AUTOIMMUNE DYSFUNCTION OF VNS, THEIR RECEPTORS OR THEIR GENES POSSIBLY INVOLVING CYTOSINE-PHOSPHATE-GUANINE (CPG) FRAGMENTS. CPG FRAGMENTS ARE IMMUNOMODULATORY DINUCLEOTIDES SERVING AS 'FRIEND OR FOE' RECOGNITION SYSTEMS TO DIFFERENTIATE BACTERIAL AND VIRAL (HYPOMETHYLATED CPG) FROM MAMMALIAN (METHYLATED CPG) DNA. HOWEVER HYPOMETHYLATION DISORDERS AFFECTING THESE FRAGMENTS IN MAMMALS MAY CONVERT THEM TO DYSFUNCTIONAL STATES BY PROMOTING AUTOIMMUNE INFLAMMATORY REACTIONS. EPIGENETIC MECHANISMS ACTING ON GENE PROMOTER REGIONS MAY CONTRIBUTE TO THE DEVELOPMENT OF VN AUTOIMMUNE FATIGUE-RELATED DISORDERS THROUGH CPG FRAGMENTS LOCATED IN VITAL SEGMENTS OF VN/RECEPTOR GENES BY CAUSING SIGNALLING DEFECTS WITH PROFOUND IMPLICATIONS FOR VN FUNCTION. NEUROTRANSMITTER DYSFUNCTION PARTICULARLY GLUTAMATERGIC TRANSMISSION COULD ALSO RESULT WITH DISRUPTION OF NEURONAL CELLULAR BIOCHEMICAL FUNCTIONS SUCH AS AMMONIA REGULATION. ENDOSOMAL ACIDITY AND MITOCHONDRIAL MEMBRANE POTENTIAL MODIFIERS SUCH AS CHLOROQUINE, TOGETHER WITH IMMUNOREGULATORY THERAPIES, MAY HAVE THERAPEUTIC IMPLICATIONS IN PROTECTING AGAINST THESE APPARENT AUTOIMMUNE DISORDERS. THIS PAPER EXAMINES SPECIFIC EPIGENETIC AND BIOCHEMICAL MECHANISMS POSSIBLY MEDIATED BY VN OR RECEPTOR GENES RESULTING IN POSTULATED VN AUTOIMMUNE FATIGUE-RELATED DISORDERS. THESE MECHANISMS MAY HAVE IMPLICATIONS FOR TREATMENT AND PREVENTION OPTIONS FOR VN AUTOIMMUNE DISORDERS. VN AUTOIMMUNE PROCESSES HAVE IMPLICATIONS FOR MILITARY MEDICINE WHERE RADIOLOGICAL, CHEMICAL AND BIOLOGICAL AGENTS MAY PLAY AN IMPORTANT ROLE IN PATHOGENESIS. 2005 6 5010 35 PEROXIDATION OF LINOLEIC, ARACHIDONIC AND OLEIC ACID IN RELATION TO THE INDUCTION OF OXIDATIVE DNA DAMAGE AND CYTOGENETIC EFFECTS. IN THE PRESENT STUDY, THE POSSIBLE ROLE OF THE POLYUNSATURATED FATTY ACIDS LINOLEIC AND ARACHIDONIC ACID IN THE CHEMICAL INDUCTION OF CARCINOGENESIS HAS BEEN INVESTIGATED. ANALYSIS OF 7,8-DIHYDRO-8-OXO-2'-DEOXYGUANOSINE (8-OXODG) LEVELS IN 2'-DEOXYGUANOSINE (DG) AND ISOLATED DNA HAS DEMONSTRATED THAT LINOLEIC AND ARACHIDONIC ACID ARE CAPABLE OF INDUCING THIS SPECIFIC GENOTOXIC DAMAGE. THIS EFFECT APPEARS TO BE RELATED TO THE DEGREE OF FATTY ACID UNSATURATION, SINCE IT WAS NOT INDUCED BY MONOUNSATURATED OLEIC ACID. ENZYMATIC PEROXIDATION OF LINOLEIC AND ARACHIDONIC ACID RESULTED IN A SIGNIFICANT INCREASE IN OXIDATIVE DNA DAMAGE. STUDIES ON THE INTERFERENCE OF RADICAL SCAVENGERS WITH THE INDUCTION OF 8-OXODG IN COMBINATION WITH ELECTRON SPIN RESONANCE SPECTROSCOPY DEMONSTRATED THAT THE SUPEROXIDE ANION WAS GENERATED DURING PEROXIDATION OF THESE FATTY ACIDS AND THAT SINGLET OXYGEN IS MOST LIKELY INVOLVED IN THE FORMATION OF OXIDATIVE DNA DAMAGE. THE LEVEL OF OXIDATIVE DAMAGE IN DG AND SINGLE-STRANDED DNA WAS HIGHER AS COMPARED TO THAT IN NATIVE DNA AFTER EQUIMOLAR TREATMENT. EXPOSURE OF HUMAN LYMPHOCYTES TO LINOLEIC OR ARACHIDONIC ACID DID NOT RESULT IN A SIGNIFICANT INCREASE IN LEVELS OF 8-OXODG. THIS MAY INDICATE THAT THE RATE OF INTRACELLULAR PEROXIDATION IS RELATIVELY LOW AND/OR THAT NUCLEAR DNA IN INTACT CELLS IS EFFECTIVELY PROTECTED AGAINST GENETIC DAMAGE INDUCED BY REACTIVE OXYGEN SPECIES. IT IS THEREFORE CONCLUDED THAT RELATIVELY SHORT PERIODS OF LINOLEIC OR ARACHIDONIC ACID ADMINISTRATION ARE NOT LIKELY TO IMPOSE A DIRECT GENOTOXIC RISK. IT CAN, HOWEVER, NOT BE EXCLUDED THAT CHRONIC EXPOSURE TO POLYUNSATURATED FATTY ACIDS INDUCES OXIDATIVE DNA DAMAGE OR IS RELATED TO CANCER RISK BY EPIGENETIC MECHANISMS, AS IS ALSO INDICATED BY THE OBSERVED CYTOTOXIC EFFECTS OF LINOLEIC AND ARACHIDONIC ACID. 1994 7 4348 54 MIR-146A DYSREGULATES ENERGY METABOLISM DURING NEUROINFLAMMATION. ALZHEIMER'S DISEASE (AD) AND OTHER NEURODEGENERATIVE DISEASES ARE CHARACTERIZED BY CHRONIC NEUROINFLAMMATION AND A REDUCTION IN BRAIN ENERGY METABOLISM. AN IMPORTANT ROLE HAS EMERGED FOR SMALL, NON-CODING RNA MOLECULES KNOWN AS MICRORNAS (MIRNAS) IN THE PATHOPHYSIOLOGY OF MANY NEURODEGENERATIVE DISORDERS. AS EPIGENETIC REGULATORS, MIRNAS POSSESS THE CAPACITY TO REGULATE AND FINE TUNE PROTEIN PRODUCTION BY INHIBITING TRANSLATION. SEVERAL MIRNAS, WHICH INCLUDE MIR-146A, ARE ELEVATED IN THE BRAIN, CSF, AND PLASMA OF AD PATIENTS. MIR-146A PARTICIPATES IN PATHWAYS THAT REGULATE IMMUNE ACTIVATION AND HAS SEVERAL MRNA TARGETS WHICH ENCODE FOR PROTEINS INVOLVED IN CELLULAR ENERGY METABOLISM. AN ADDITIONAL ROLE FOR EXTRACELLULAR VESICLES (EVS) HAS ALSO EMERGED IN THE PROGRESSION AD, AS EVS CAN TRANSFER FUNCTIONALLY ACTIVE PROTEINS AND RNAS FROM DISEASED TO HEALTHY CELLS. IN THE CURRENT STUDY, WE EXPOSED VARIOUS CELL TYPES PRESENT WITHIN THE CNS TO IMMUNOMODULATORY MOLECULES AND OBSERVED SIGNIFICANT UPREGULATION OF MIR-146A EXPRESSION, BOTH WITHIN CELLS AND WITHIN THEIR SECRETED EVS. FURTHER, WE ASSESSED THE EFFECTS OF MIR-146A OVEREXPRESSION ON BIOENERGETIC FUNCTION IN PRIMARY RAT GLIAL CELLS AND FOUND SIGNIFICANT REDUCTIONS IN OXIDATIVE PHOSPHORYLATION AND GLYCOLYSIS. LASTLY, WE CORRELATED MIR-146A EXPRESSION LEVELS WITHIN VARIOUS REGIONS OF THE AD BRAIN TO DISEASE STAGING AND FOUND SIGNIFICANT, POSITIVE CORRELATIONS. THESE NOVEL RESULTS DEMONSTRATE THAT THE MODULATION OF MIR-146A IN RESPONSE TO NEUROINFLAMMATORY STIMULI MAY MEDIATE THE LOSS OF MITOCHONDRIAL INTEGRITY AND FUNCTION IN CELLS, THEREBY CONTRIBUTING TO THE PROGRESSION OF BETA-AMYLOID AND TAU PATHOLOGY IN THE AD BRAIN. MULTIPLE INFLAMMATORY STIMULI CAN UPREGULATE MIRNA-146A EXPRESSION WITHIN NEURONS, MIXED GLIAL CELLS, AND BRAIN ENDOTHELIAL CELLS, WHICH IS EITHER RETAINED WITHIN THESE CELLS OR RELEASED FROM THEM AS EXTRACELLULAR VESICLE CARGO. THE UPREGULATION OF MIR-146A DISRUPTS CELLULAR BIOENERGETICS IN MIXED GLIAL CELLS. THIS MECHANISM MAY PLAY A CRITICAL ROLE IN THE NEUROINFLAMMATORY RESPONSE OBSERVED DURING ALZHEIMER'S DISEASE. 2022 8 5112 33 POLYUNSATURATED FATTY ACIDS: BIOCHEMICAL, NUTRITIONAL AND EPIGENETIC PROPERTIES. DIETARY POLYUNSATURATED FATTY ACIDS (PUFA) HAVE EFFECTS ON DIVERSE PHYSIOLOGICAL PROCESSES IMPACTING NORMAL HEALTH AND CHRONIC DISEASES, SUCH AS THE REGULATION OF PLASMA LIPID LEVELS, CARDIOVASCULAR AND IMMUNE FUNCTION, INSULIN ACTION AND NEURONAL DEVELOPMENT AND VISUAL FUNCTION. INGESTION OF PUFA WILL LEAD TO THEIR DISTRIBUTION TO VIRTUALLY EVERY CELL IN THE BODY WITH EFFECTS ON MEMBRANE COMPOSITION AND FUNCTION, EICOSANOID SYNTHESIS, CELLULAR SIGNALING AND REGULATION OF GENE EXPRESSION. CELL SPECIFIC LIPID METABOLISM, AS WELL AS THE EXPRESSION OF FATTY ACID-REGULATED TRANSCRIPTION FACTORS, LIKELY PLAY AN IMPORTANT ROLE IN DETERMINING HOW CELLS RESPOND TO CHANGES IN PUFA COMPOSITION. THIS REVIEW WILL FOCUS ON RECENT ADVANCES ON THE ESSENTIALITY OF THESE MOLECULES AND ON THEIR INTERPLAY IN CELL PHYSIOLOGY, LEADING TO NEW PERSPECTIVE IN DIFFERENT THERAPEUTIC FIELDS. 2004 9 4625 37 NEUROBIOLOGY OF VITAMIN C: EXPANDING THE FOCUS FROM ANTIOXIDANT TO ENDOGENOUS NEUROMODULATOR. ASCORBIC ACID (AA) IS A WATER-SOLUBLE VITAMIN (C) FOUND IN ALL BODILY ORGANS. MOST MAMMALS SYNTHESIZE IT, HUMANS ARE REQUIRED TO EAT IT, BUT ALL MAMMALS NEED IT FOR HEALTHY FUNCTIONING. AA REACHES ITS HIGHEST CONCENTRATION IN THE BRAIN WHERE BOTH NEURONS AND GLIA RELY ON TIGHTLY REGULATED UPTAKE FROM BLOOD VIA THE GLUCOSE TRANSPORT SYSTEM AND SODIUM-COUPLED ACTIVE TRANSPORT TO ACCUMULATE AND MAINTAIN AA AT MILLIMOLAR LEVELS. AS A PROTOTYPE ANTIOXIDANT, AA IS NOT ONLY NEUROPROTECTIVE, BUT ALSO FUNCTIONS AS A COFACTOR IN REDOX-COUPLED REACTIONS ESSENTIAL FOR THE SYNTHESIS OF NEUROTRANSMITTERS (E.G., DOPAMINE AND NOREPINEPHRINE) AND PARACRINE LIPID MEDIATORS (E.G., EPOXIECOISATRIENOIC ACIDS) AS WELL AS THE EPIGENETIC REGULATION OF DNA. ALTHOUGH REDOX CAPACITY LED TO THE PROMOTION OF AA IN HIGH DOSES AS POTENTIAL TREATMENT FOR VARIOUS NEUROPATHOLOGICAL AND PSYCHIATRIC CONDITIONS, AMPLE EVIDENCE HAS NOT SUPPORTED THIS THERAPEUTIC STRATEGY. HERE, WE FOCUS ON SOME LONG-NEGLECTED ASPECTS OF AA NEUROBIOLOGY, INCLUDING ITS MODULATORY ROLE IN SYNAPTIC TRANSMISSION AS DEMONSTRATED BY THE LONG-ESTABLISHED LINK BETWEEN RELEASE OF ENDOGENOUS AA IN BRAIN EXTRACELLULAR FLUID AND THE CLEARANCE OF GLUTAMATE, AN EXCITATORY AMINO ACID. EVIDENCE THAT THIS LINK CAN BE DISRUPTED IN ANIMAL MODELS OF HUNTINGTON S DISEASE IS REVEALING OPPORTUNITIES FOR NEW RESEARCH PATHWAYS AND THERAPEUTIC APPLICATIONS (E.G., EPILEPSY AND PAIN MANAGEMENT). IN FACT, WE SUGGEST THAT IMPROVED UNDERSTANDING OF THE REGULATION OF ENDOGENOUS AA AND ITS INTERACTION WITH KEY BRAIN NEUROTRANSMITTER SYSTEMS, RATHER THAN ADMINISTRATION OF AA IN EXCESS, SHOULD BE THE TARGET OF FUTURE BRAIN-BASED THERAPIES. 2019 10 1066 38 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 11 2882 36 G-PROTEIN-COUPLED RECEPTOR GPR17 REGULATES OLIGODENDROCYTE DIFFERENTIATION IN RESPONSE TO LYSOLECITHIN-INDUCED DEMYELINATION. OLIGODENDROCYTES ARE THE MYELIN-PRODUCING CELLS OF THE CENTRAL NERVOUS SYSTEM (CNS). A VARIETY OF BRAIN DISORDERS FROM "CLASSICAL" DEMYELINATING DISEASES, SUCH AS MULTIPLE SCLEROSIS, STROKE, SCHIZOPHRENIA, DEPRESSION, DOWN SYNDROME AND AUTISM, ARE SHOWN MYELINATION DEFECTS. OLIGODENDROCYTE MYELINATION IS REGULATED BY A COMPLEX INTERPLAY OF INTRINSIC, EPIGENETIC AND EXTRINSIC FACTORS. GPR17 (G PROTEIN-COUPLED RECEPTOR 17) IS A G PROTEIN-COUPLED RECEPTOR, AND HAS BEEN IDENTIFIED TO BE A REGULATOR FOR OLIGODENDROCYTE DEVELOPMENT. HERE, WE DEMONSTRATE THAT THE ABSENCE OF GPR17 ENHANCES REMYELINATION IN VIVO WITH A TOXIN-INDUCED MODEL WHEREBY FOCAL DEMYELINATED LESIONS ARE GENERATED IN SPINAL CORD WHITE MATTER OF ADULT MICE BY LOCALIZED INJECTION OF LPC(L-A-LYSOPHOSPHATIDYLCHOLINE). THE INCREASED EXPRESSION OF THE ACTIVATED FORM OF ERK1/2 (PHOSPHO-ERK1/2) IN LESION AREAS SUGGESTED THE POTENTIAL ROLE OF ERK1/2 ACTIVITY ON THE GPR17-DEPENDENT MODULATION OF MYELINATION. THE ABSENCE OF GPR17 ENHANCES REMYELINATION IS CORRELATE WITH THE ACTIVATED ERK1/2 (PHOSPHO-ERK1/2).BEING A MEMBRANE RECEPTOR, GPR17 REPRESENTS AN IDEAL DRUGGABLE TARGET TO BE EXPLOITED FOR INNOVATIVE REGENERATIVE APPROACHES TO ACUTE AND CHRONIC CNS DISEASES. 2018 12 3701 31 INFLAMMATORY RESPONSE TO REGULATED CELL DEATH IN GOUT AND ITS FUNCTIONAL IMPLICATIONS. GOUT, A CHRONIC INFLAMMATORY ARTHRITIS DISEASE, IS CHARACTERIZED BY HYPERURICEMIA AND CAUSED BY INTERACTIONS BETWEEN GENETIC, EPIGENETIC, AND METABOLIC FACTORS. ACUTE GOUT SYMPTOMS ARE TRIGGERED BY THE INFLAMMATORY RESPONSE TO MONOSODIUM URATE CRYSTALS, WHICH IS MEDIATED BY THE INNATE IMMUNE SYSTEM AND IMMUNE CELLS (E.G., MACROPHAGES AND NEUTROPHILS), THE NACHT, LRR, AND PYD DOMAINS-CONTAINING PROTEIN 3 (NLRP3) INFLAMMASOME ACTIVATION, AND PRO-INFLAMMATORY CYTOKINE (E.G., IL-1BETA) RELEASE. RECENT STUDIES HAVE INDICATED THAT THE MULTIPLE PROGRAMMED CELL DEATH PATHWAYS INVOLVED IN THE INFLAMMATORY RESPONSE INCLUDE PYROPTOSIS, NETOSIS, NECROPTOSIS, AND APOPTOSIS, WHICH INITIATE INFLAMMATORY REACTIONS. IN THIS REVIEW, WE EXPLORE THE CORRELATION AND INTERACTIONS AMONG THESE FACTORS AND THEIR ROLES IN THE PATHOGENESIS OF GOUT TO PROVIDE FUTURE RESEARCH DIRECTIONS AND POSSIBILITIES FOR IDENTIFYING POTENTIAL NOVEL THERAPEUTIC TARGETS AND ENHANCING OUR UNDERSTANDING OF GOUT PATHOGENESIS. 2022 13 593 35 BET PROTEIN INHIBITION REGULATES CYTOKINE PRODUCTION AND PROMOTES NEUROPROTECTION AFTER SPINAL CORD INJURY. BACKGROUND: SPINAL CORD INJURY (SCI) USUALLY CAUSES A DEVASTATING LIFELONG DISABILITY FOR PATIENTS. AFTER A TRAUMATIC LESION, DISRUPTION OF THE BLOOD-SPINAL CORD BARRIER INDUCES THE INFILTRATION OF MACROPHAGES INTO THE LESION SITE AND THE ACTIVATION OF RESIDENT GLIAL CELLS, WHICH RELEASE CYTOKINES AND CHEMOKINES. THESE EVENTS RESULT IN A PERSISTENT INFLAMMATION, WHICH HAS BOTH DETRIMENTAL AND BENEFICIAL EFFECTS, BUT EVENTUALLY LIMITS FUNCTIONAL RECOVERY AND CONTRIBUTES TO THE APPEARANCE OF NEUROPATHIC PAIN. BROMODOMAIN AND EXTRA-TERMINAL DOMAIN (BET) PROTEINS ARE EPIGENETIC READERS THAT REGULATE THE EXPRESSION OF INFLAMMATORY GENES BY INTERACTING WITH ACETYLATED LYSINE RESIDUES. WHILE BET INHIBITORS ARE A PROMISING THERAPEUTIC STRATEGY FOR CANCER, LITTLE IS KNOWN ABOUT THEIR IMPLICATION AFTER SCI. THUS, THE CURRENT STUDY WAS AIMED TO INVESTIGATE THE ANTI-INFLAMMATORY ROLE OF BET INHIBITORS IN THIS PATHOLOGIC CONDITION. METHODS: WE EVALUATED THE EFFECTIVENESS OF THE BET INHIBITOR JQ1 TO MODIFY MACROPHAGE REACTIVITY IN VITRO AND TO MODULATE INFLAMMATION IN A SCI MICE MODEL. WE ANALYZED THE EFFECTS OF BET INHIBITION IN PRO-INFLAMMATORY AND ANTI-INFLAMMATORY CYTOKINE PRODUCTION IN VITRO AND IN VIVO. WE DETERMINED THE EFFECTIVENESS OF BET INHIBITION IN TISSUE SPARING, INFLAMMATION, NEURONAL PROTECTION, AND BEHAVIORAL OUTCOME AFTER SCI. RESULTS: WE HAVE FOUND THAT THE BET INHIBITOR JQ1 REDUCED THE LEVELS OF PRO-INFLAMMATORY MEDIATORS AND INCREASED THE EXPRESSION OF ANTI-INFLAMMATORY CYTOKINES. A PROLONGED TREATMENT WITH JQ1 ALSO DECREASED REACTIVITY OF MICROGLIA/MACROPHAGES, ENHANCED NEUROPROTECTION AND FUNCTIONAL RECOVERY, AND ACUTELY REDUCED NEUROPATHIC PAIN AFTER SCI. CONCLUSIONS: BET PROTEIN INHIBITION IS AN EFFECTIVE TREATMENT TO REGULATE CYTOKINE PRODUCTION AND PROMOTE NEUROPROTECTION AFTER SCI. THESE NOVEL RESULTS DEMONSTRATE FOR THE FIRST TIME THAT TARGETING BET PROTEINS IS AN ENCOURAGING APPROACH FOR SCI REPAIR AND A POTENTIAL STRATEGY TO TREAT OTHER INFLAMMATORY PATHOLOGIES. 2019 14 4044 26 MACROPHAGES IN OXIDATIVE STRESS AND MODELS TO EVALUATE THE ANTIOXIDANT FUNCTION OF DIETARY NATURAL COMPOUNDS. ANTIOXIDANT TESTING OF NATURAL PRODUCTS HAS ATTRACTED INCREASING INTEREST IN RECENT YEARS, MAINLY DUE TO THE FACT THAT AN ANTIOXIDANT-RICH DIET MIGHT PROVIDE HEALTH BENEFITS. ACTIVATED MACROPHAGES ARE A MAJOR SOURCE OF REACTIVE OXYGEN SPECIES, REACTIVE NITROGEN SPECIES, AND PEROXYNITRITE GENERATED THROUGH THE SO-CALLED RESPIRATORY BURST. CONSTITUTIVELY RELEASED PROINFLAMMATORY CYTOKINE, ESPECIALLY TUMOR NECROSIS FACTOR-ALPHA, TRIGGERS NUCLEAR FACTOR-KAPPAB, AND ACTIVATOR PROTEIN-1 TRANSLOCATION LEADING TO THE OVER PRODUCTION OF REACTIVE OXYGEN SPECIES AND REACTIVE NITROGEN SPECIES IN MACROPHAGES. ACTIVATION OF TRANSCRIPTION FACTORS IN THE LONG-LIVED TISSUE-RESIDENT MACROPHAGES AND/OR MONOCYTE-DERIVED MACROPHAGES, TRIGGER EPIGENETIC MODIFICATIONS LEADING TO THE PATHOGENESIS OF CHRONIC DISEASES. NUTRACEUTICALS INCLUDING LIPID RAFT STRUCTURE DISRUPTION AGENT, CHOLESTEROL DEPLETION AGENT, FARNESYLTRANSFERASE INHIBITOR, NUCLEAR FACTOR-KAPPAB BLOCKER (ALPHA,BETA-UNSATURATED CARBONYL COMPOUNDS), GLUCOCORTICOID RECEPTOR AGONIST, AND PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR-GAMMA AGONIST HAVE LONG BEEN USED TO INACTIVE MACROPHAGE. THE INHIBITION EFFECTS ON THE FORMATION OF NITRIC OXIDE, SUPEROXIDE, AND NITRITE PEROXIDE MAY BE RESPONSIBLE FOR THE ANTI-INFLAMMATORY FUNCTIONALITIES. ACTIVATED MACROPHAGE MODELS COULD BE USED TO IDENTIFY THE ACTIVE COMPONENTS FOR FUNCTIONAL DIETS DEVELOPMENT THROUGH A MULTIPLE TARGETS STRATEGY. 2017 15 5408 40 REGULATION AND SIGNALING OF THE GPR17 RECEPTOR IN OLIGODENDROGLIAL CELLS. REMYELINATION, NAMELY, THE FORMATION OF NEW MYELIN SHEATHS AROUND DENUDED AXONS, COUNTERACTS AXONAL DEGENERATION AND RESTORES NEURONAL FUNCTION. CONSIDERABLE ADVANCES HAVE BEEN MADE IN UNDERSTANDING THIS REGENERATIVE PROCESS THAT OFTEN FAILS IN DISEASES LIKE MULTIPLE SCLEROSIS, LEAVING AXONS DEMYELINATED AND VULNERABLE TO DAMAGE, THUS CONTRIBUTING TO DISEASE PROGRESSION. THE IDENTIFICATION OF THE MEMBRANE RECEPTOR GPR17 ON A SUBSET OF OLIGODENDROCYTE PRECURSOR CELLS (OPCS), WHICH MEDIATE REMYELINATION IN THE ADULT CENTRAL NERVOUS SYSTEM (CNS), HAS LED TO A HUGE AMOUNT OF EVIDENCE THAT VALIDATED THIS RECEPTOR AS A NEW ATTRACTIVE TARGET FOR REMYELINATING THERAPIES. HERE, WE SUMMARIZE THE ROLE OF GPR17 IN OPC FUNCTION, MYELINATION AND REMYELINATION, DESCRIBING ITS ATYPICAL PHARMACOLOGY, ITS DOWNSTREAM SIGNALING, AND THE GENETIC AND EPIGENETIC FACTORS MODULATING ITS ACTIVITY. WE ALSO HIGHLIGHT CRUCIAL INSIGHTS INTO GPR17 PATHOPHYSIOLOGY COMING FROM THE DEMONSTRATION THAT OLIGODENDROCYTE INJURY, ASSOCIATED WITH INFLAMMATION IN CHRONIC NEURODEGENERATIVE CONDITIONS, IS INVARIABLY CHARACTERIZED BY ABNORMAL AND PERSISTENT GPR17 UPREGULATION, WHICH, IN TURN, IS ACCOMPANIED BY A BLOCK OF OPCS AT IMMATURE PREMYELINATING STAGES. FINALLY, WE DISCUSS THE CURRENT LITERATURE IN LIGHT OF THE POTENTIAL EXPLOITMENT OF GPR17 AS A THERAPEUTIC TARGET TO PROMOTE REMYELINATION. 2020 16 6166 37 THE GLUTATHIONE SYSTEM: A NEW DRUG TARGET IN NEUROIMMUNE DISORDERS. GLUTATHIONE (GSH) HAS A CRUCIAL ROLE IN CELLULAR SIGNALING AND ANTIOXIDANT DEFENSES EITHER BY REACTING DIRECTLY WITH REACTIVE OXYGEN OR NITROGEN SPECIES OR BY ACTING AS AN ESSENTIAL COFACTOR FOR GSH S-TRANSFERASES AND GLUTATHIONE PEROXIDASES. GSH ACTING IN CONCERT WITH ITS DEPENDENT ENZYMES, KNOWN AS THE GLUTATHIONE SYSTEM, IS RESPONSIBLE FOR THE DETOXIFICATION OF REACTIVE OXYGEN AND NITROGEN SPECIES (ROS/RNS) AND ELECTROPHILES PRODUCED BY XENOBIOTICS. ADEQUATE LEVELS OF GSH ARE ESSENTIAL FOR THE OPTIMAL FUNCTIONING OF THE IMMUNE SYSTEM IN GENERAL AND T CELL ACTIVATION AND DIFFERENTIATION IN PARTICULAR. GSH IS A UBIQUITOUS REGULATOR OF THE CELL CYCLE PER SE. GSH ALSO HAS CRUCIAL FUNCTIONS IN THE BRAIN AS AN ANTIOXIDANT, NEUROMODULATOR, NEUROTRANSMITTER, AND ENABLER OF NEURON SURVIVAL. DEPLETION OF GSH LEADS TO EXACERBATION OF DAMAGE BY OXIDATIVE AND NITROSATIVE STRESS; HYPERNITROSYLATION; INCREASED LEVELS OF PROINFLAMMATORY MEDIATORS AND INFLAMMATORY POTENTIAL; DYSFUNCTIONS OF INTRACELLULAR SIGNALING NETWORKS, E.G., P53, NUCLEAR FACTOR-KAPPAB, AND JANUS KINASES; DECREASED CELL PROLIFERATION AND DNA SYNTHESIS; INACTIVATION OF COMPLEX I OF THE ELECTRON TRANSPORT CHAIN; ACTIVATION OF CYTOCHROME C AND THE APOPTOTIC MACHINERY; BLOCKADE OF THE METHIONINE CYCLE; AND COMPROMISED EPIGENETIC REGULATION OF GENE EXPRESSION. AS SUCH, GSH DEPLETION HAS MARKED CONSEQUENCES FOR THE HOMEOSTATIC CONTROL OF THE IMMUNE SYSTEM, OXIDATIVE AND NITROSATIVE STRESS (O&NS) PATHWAYS, REGULATION OF ENERGY PRODUCTION, AND MITOCHONDRIAL SURVIVAL AS WELL. GSH DEPLETION AND CONCOMITANT INCREASE IN O&NS AND MITOCHONDRIAL DYSFUNCTIONS PLAY A ROLE IN THE PATHOPHYSIOLOGY OF DIVERSE NEUROIMMUNE DISORDERS, INCLUDING DEPRESSION, MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME AND PARKINSON'S DISEASE, SUGGESTING THAT DEPLETED GSH IS AN INTEGRAL PART OF THESE DISEASES. THERAPEUTICAL INTERVENTIONS THAT AIM TO INCREASE GSH CONCENTRATIONS IN VIVO INCLUDE N-ACETYL CYSTEINE; NRF-2 ACTIVATION VIA HYPERBARIC OXYGEN THERAPY; DIMETHYL FUMARATE; PHYTOCHEMICALS, INCLUDING CURCUMIN, RESVERATROL, AND CINNAMON; AND FOLATE SUPPLEMENTATION. 2014 17 6891 37 [SIGNAL RECEPTORS OF CONGENITAL IMMUNITY: A NEW MOLECULAR TARGET FOR DIAGNOSTICS AND TREATMENT OF INFLAMMATORY DISEASES]. THE DISCOVERY OF SIGNAL RECEPTORS OF CONGENITAL IMMUNITY (SIGNAL PRR) NOT ONLY PROVIDED A NOVEL VIEW OF BASIC ASPECTS OF PATHOGENESIS OF CHRONIC INFLAMMATORY DISEASES BUT ALSO CREATED A BASIS FOR THE DEVELOPMENT OF ADDITIONAL DIAGNOSTIC CRITERIA FOR THESE PATHOLOGIES AND NEW PHARMACEUTICALS FOR THEIR TREATMENT. REDUCED EXPRESSION AND FUNCTION OF PRR DUE TO MUTATIONS/POLYMORPHISMS OR EPIGENETIC DISTURBANCES OF REGULATION CAN BE REGARDED AS IMMUNODEFICIENT CONDITIONS MANIFEST AS SEVERE INFECTIOUS INFLAMMATORY DISEASES. IN CONTRAST, EXCESSIVE EXPRESSION AND ACTIVATION OF PRR AS A RULE LEADS TO CHRONIC AUTOINFLAMMATORY, AUTOIMMUNE, AND ATOPIC DISEASES INVOLVING ADAPTIVE IMMUNITY AND AGGRESSION AGAINST OWN TISSUES AND CELLS. ASSESSMENT OF CERTAIN MUTATIONS IN PRR GENES, THEIR EXPRESSION AND ACTIVATION PROVIDES A POWERFUL TOOL FOR IN-DEPTH DIAGNOSTICS OF INFLAMMATORY DISEASES. SIMULTANEOUSLY, NEW LINES OF IMMUNOSTIMULATING AND ANTI-INFLAMMATORY THERAPY ARE DEVELOPED BASED ON THE KNOWLEDGE OF MOLECULAR PHYSIOLOGY OF PRR WITH THE USE OF SYNTHETIC AGONISTS AND ANTAGONISTS OF SIGNAL PRR. 2011 18 4977 52 PATHOPHYSIOLOGY AND EVOLUTIONARY ASPECTS OF DIETARY FATS AND LONG-CHAIN POLYUNSATURATED FATTY ACIDS ACROSS THE LIFE CYCLE. DIETARY FAT IS OUR SECOND MOST IMPORTANT ENERGY-PRODUCING MACRONUTRIENT. IT ALSO CONTAINS FATTY ACIDS AND VITAMINS ESSENTIAL FOR GROWTH, DEVELOPMENT, AND MAINTENANCE OF GOOD HEALTH. DIETARY FAT QUANTITY AND QUALITY HAVE BEEN SUBJECT TO TREMENDOUS CHANGE OVER THE PAST 10,000 YEARS. THIS HAS, TOGETHER WITH OTHER MAN-MADE CHANGES IN OUR ENVIRONMENT, CAUSED A CONFLICT WITH OUR SLOWLY ADAPTING GENOME THAT IS IMPLICATED IN "TYPICALLY WESTERN" DISEASES. RATHER THAN REDUCING OUR LIFE EXPECTANCY, THESE DISEASES NOTABLY DIMINISH OUR NUMBER OF YEARS IN HEALTH. IMPORTANT CHANGES IN DIETARY FAT QUALITY ARE THE INCREASED INTAKES OF CERTAIN SATURATED FATTY ACIDS (SAFA) AND LINOLEIC ACID (LA), INTRODUCTION OF INDUSTRIALLY PRODUCED TRANS FATTY ACIDS, AND REDUCED INTAKES OF OMEGA3 FATTY ACIDS, NOTABLY ALPHA-LINOLENIC ACID (ALA) FROM VEGETABLE SOURCES AND EICOSAPENTAENOIC ACID (EPA) AND DOCOSAHEXAENOIC ACID (DHA) FROM FISH. THE PATHOPHYSIOLOGICAL EFFECTS OF THESE CHANGES ARE DIVERSE, BUT ARE INCREASINGLY ASCRIBED TO INDUCTION OF A PROINFLAMMATORY STATE THAT PROGRESSES EASILY TO CHRONIC LOW-GRADE INFLAMMATION. THE LATTER MIGHT AFFECT VIRTUALLY ALL ORGANS AND SYSTEMS, POSSIBLY BEGINNING AT CONCEPTION, AND POSSIBLY EVEN PRIOR TO GAMETOGENESIS THROUGH EPIGENETIC ALTERATIONS. LOW-GRADE INFLAMMATION MIGHT BE A COMMON DENOMINATOR OF THE METABOLIC SYNDROME AND ITS SEQUELAE (E.G., CORONARY ARTERY DISEASE (CAD), DIABETES MELLITUS TYPE 2, SOME TYPES OF CANCER, AND PREGNANCY COMPLICATIONS), SOME PSYCHIATRIC DISEASES (E.G., MAJOR AND POSTPARTUM DEPRESSION, SCHIZOPHRENIA, AND AUTISM), AND NEURODEGENERATIVE DISEASES (E.G., ALZHEIMER'S DISEASE, PARKINSON'S DISEASE). THE LONG-CHAIN POLYUNSATURATED FATTY ACIDS (LCPUFA) ARACHIDONIC ACID (AA), EPA, AND DHA ARE INTIMATELY RELATED TO THE INITIATION AND RESOLUTION OF INFLAMMATORY RESPONSES. THE CURRENT BALANCE BETWEEN AA AND EPA + DHA IS HOWEVER DISTURBED BY THE DOMINANCE OF AA, WHICH ORIGINATES FROM THE DIET OR SYNTHESIS FROM LA. LCPUFA ARE TOGETHER WITH THEIR HIGHLY POTENT METABOLITES (PROSTAGLANDINS, THROMBOXANES, LEUKOTRIENES, RESOLVINS, AND (NEURO)PROTECTINS) INVOLVED IN THE FUNCTIONING OF MEMBRANE-BOUND RECEPTORS, TRANSPORTERS, ION CHANNELS, AND ENZYMES, AND ALSO IN SIGNAL TRANSDUCTION AND GENE EXPRESSION. AMONG THEIR MANY TARGETS ARE NUCLEAR RECEPTORS WHICH, UPON LIGATION WITH LCPUFA AND THEIR METABOLITES, FUNCTION AS TRANSCRIPTION FACTORS OF A VARIETY OF GENES FUNCTIONING IN MANY PATHWAYS. FOR INSTANCE, THE TARGETED PEROXISOME PROLIFERATORS-ACTIVATED RECEPTORS (PPARS) ARE STRATEGIC INTERMEDIATES IN THE COORDINATED EXPRESSION OF PROTEINS WITH FUNCTIONS IN, FOR EXAMPLE, LIPID AND GLUCOSE HOMEOSTASIS AND INFLAMMATORY REACTIONS. MANY INTERVENTIONS HAVE BEEN CONDUCTED WITH LCPUFA, ESPECIALLY EPA AND DHA, AIMING AT PRIMARY AND SECONDARY CAD PREVENTIONS, IMPROVEMENT OF FETAL AND NEWBORN (BRAIN) DEVELOPMENT BY SUPPLEMENTATION DURING PREGNANCY OR EARLY POSTNATAL LIFE, AND IN PSYCHIATRIC DISEASES. CONSENSUS HAS BEEN REACHED THAT THOSE IN CAD AND DEPRESSION ARE POSITIVE, ALTHOUGH MORE LARGE-SCALE TRIALS ARE NEEDED. MANY RECOMMENDATIONS FOR THE INTAKES OF SATURATED FAT, TRANS FAT AND EPA + DHA HAVE BEEN ISSUED, NOTABLY FOR CAD PREVENTION, AND ALSO FOR EPA + DHA INTAKES BY PREGNANT WOMEN AND FOR AA, EPA, AND DHA INTAKES BY NEWBORNS. THE ULTIMATE GOAL MIGHT, HOWEVER, BE TO RETURN TO THE FAT QUALITY OF OUR ANCIENT DIET ON WHICH OUR GENES HAVE EVOLVED DURING THE PAST MILLION YEARS OF EVOLUTION, WHILE THIS ACTUALLY APPLIES FOR OUR ENTIRE DIETARY COMPOSITION AND LIFESTYLE, AS TRANSLATED TO THE CULTURE OF THE CURRENT SOCIETY. 2010 19 620 52 BIOCHEMISTRY AND MOLECULAR BIOLOGY OF GELATINASE B OR MATRIX METALLOPROTEINASE-9 (MMP-9): THE NEXT DECADE. RESEARCH ON MATRIX METALLOPROTEINASES (MMPS) AND IN PARTICULAR ON GELATINASE B, ALIAS MMP-9, HAS GROWN EXPONENTIALLY IN THE DECADE 2003-2012. STRUCTURAL DETAILS ABOUT FLEXIBILITY OF MMP-9 MONOMERS, TOGETHER WITH GLYCOSYLATION, OLIGOMERIZATION, HETEROGENEITY AND INSTABILITY OF THE WILDTYPE ENZYME EXPLAIN WHY CRYSTALLOGRAPHY EXPERIMENTS HAVE NOT YET BEEN SUCCESSFUL FOR THE INTACT ENZYME. MMP-9 MAY BE VIEWED AS A MULTIDOMAIN ENZYME IN WHICH THE HEMOPEXIN, THE O-GLYCOSYLATED AND THE CATALYTIC DOMAINS YIELD SUPPORT FOR ATTACHMENT, ARTICULATION AND CATALYSIS, RESPECTIVELY. THE STEPWISE PROTEOLYTIC ACTIVATION OF THE INACTIVE ZYMOGEN INTO A CATALYTICALLY ACTIVE FORM BECOMES GRADUALLY BETTER UNDERSTOOD. PRIMING OF ACTIVATION BY MMP-3 MAY BE EXECUTED BY MEPRINS THAT DESTABILIZE THE INTERACTION OF THE AMINOTERMINUS WITH THE THIRD FIBRONECTIN REPEAT. ALTERNATIVELY, AUTOCATALYTIC ACTIVATION MAY OCCUR IN THE PRESENCE OF MOLECULES THAT TIGHTLY BIND TO THE CATALYTIC SITE AND THAT PUSH THE CYSTEIN RESIDUE IN THE PRODOMAIN AWAY FROM THE CATALYTIC ZINC ION. THANKS TO THE DEVELOPMENT OF DEGRADOMICS TECHNOLOGIES, SUBSTRATE REPERTOIRES OF MMP-9 HAVE BEEN DEFINED, BUT IT REMAINS A CHALLENGE TO DETERMINE AND PROVE WHICH SUBSTRATES ARE BIOLOGICALLY RELEVANT. THE SUBSTRATE REPERTOIRE HAS BEEN ENLARGED FROM EXTRACELLULAR TO MEMBRANE-BOUND AND EFFICIENT INTRACELLULAR SUBSTRATES, SUCH AS CRYSTALLINS, TUBULINS AND ACTINS. BIOLOGICAL STUDIES OF MMP-9 HAVE TUNED THE FIELD FROM BEING PRIMARILY CANCER-ORIENTED TOWARDS VASCULAR AND INFLAMMATORY RESEARCH. IN TUMOR BIOLOGY, IT HAS BEEN INCREASINGLY APPRECIATED THAT MMP-9 FROM INFLAMMATORY CELLS, PARTICULARLY NEUTROPHILS, CO-DETERMINES PROGNOSIS AND OUTCOME. ASIDE FROM THE CATALYTIC FUNCTIONS EXECUTED BY AMINOTERMINAL DOMAINS OF MMP-9, THE CARBOXYTERMINAL HEMOPEXIN (PEX) DOMAIN OF GELATINASE B EXERTS NON-CATALYTIC ANTI-APOPTOTIC SIGNALING EFFECTS. THE RECOGNITION THAT GELATINASE B IS INDUCED BY MANY PRO-INFLAMMATORY CYTOKINES, WHEREAS ITS INHIBITORS ARE INCREASED BY ANTI-INFLAMMATORY CYTOKINES, HAS GENERATED INTEREST TO TARGET MMP-9 IN ACUTE LETHAL CONDITIONS, SUCH AS BACTERIAL MENINGITIS, SEPSIS AND ENDOTOXIN SHOCK, AND IN ACUTE EXACERBATIONS OF CHRONIC DISEASES. PREVIOUSLY DESCRIBED TRANSCRIPTIONAL REGULATION OF MMP-9 IS COMPLEMENTED BY EPIGENETIC CHECKPOINTS, INCLUDING HISTONE MODIFICATIONS AND MICRORNAS. BECAUSE ACTIVATION OF PROMMP-9 MAY BE EXECUTED BY OTHER MMPS, THE THERAPEUTIC DOGMA THAT MMP INHIBITORS NEED TO BE HIGHLY SELECTIVE MAY BE KEYED DOWN FOR THE TREATMENT OF LIFE-THREATENING CONDITIONS. WHEN INFLAMMATION AND MMP-9 FULFILL BENEFICIAL FUNCTIONS TO CLEAR DAMAGING PROTEIN COMPLEXES, SUCH AS IN SYSTEMIC AUTOIMMUNE DISEASES, THERAPEUTIC MMP INHIBITION HAS TO BE AVOIDED. IN MMP9 GENE KNOCKOUT MICE, SPECIFIC SPONTANEOUS PHENOTYPES EMERGED WITH EFFECTS ON THE SKELETAL, REPRODUCTIVE AND NERVOUS SYSTEMS. THESE FINDINGS NOT ONLY HAVE CLINICAL CORRELATES IN BONE GROWTH AND FERTILITY, BUT ALSO STIMULATE RESEARCH ON THE ROLES OF MMPS AND MMP-9 IN ENDOCRINOLOGY, IMMUNOLOGY AND THE NEUROSCIENCES. MMP9-DEFICIENT MICE ARE VALUABLE TOOLS TO DEFINE MMP-9 SUBSTRATES IN VIVO AND TO STUDY THE ROLE OF THIS ENZYME IN ANIMAL MODELS OF INFLAMMATORY, VASCULAR, NEOPLASTIC AND DEGENERATIVE DISEASES. FUTURE CHALLENGES INCLUDE SOLVING THE CRYSTAL STRUCTURE, DEFINITION OF THE FUNCTIONS OF COVALENT OLIGOMERS AND HETEROMERS IN BIOLOGY AND PATHOLOGY, LIFE-IMAGING OF MMP-9 ACTIVITY, SUBSTRATE DETERMINATION IN SITU AND THE STUDY OF INHIBITOR EFFECTS ON FERTILITY, CANCER AND INFLAMMATION AND IN NEUROBIOLOGY AND REGENERATIVE MEDICINE. SUCH STUDIES WILL BETTER DEFINE CONDITIONS IN WHICH INHIBITION OF MMP-9 IS BENEFICIAL OR HAS TO BE AVOIDED. 2013 20 4337 32 MICROTUBULES AS MAJOR REGULATORS OF ENDOTHELIAL FUNCTION: IMPLICATION FOR LUNG INJURY. ENDOTHELIAL DYSFUNCTION HAS BEEN ATTRIBUTED AS ONE OF THE MAJOR COMPLICATIONS IN COVID-19 PATIENTS, A GLOBAL PANDEMIC THAT HAS ALREADY CAUSED OVER 4 MILLION DEATHS WORLDWIDE. THE DYSFUNCTION OF ENDOTHELIAL BARRIER IS CHARACTERIZED BY AN INCREASE IN ENDOTHELIAL PERMEABILITY AND INFLAMMATORY RESPONSES, AND HAS EVEN BROADER IMPLICATIONS IN THE PATHOGENESIS OF ACUTE RESPIRATORY SYNDROMES SUCH AS ARDS, SEPSIS AND CHRONIC ILLNESSES REPRESENTED BY PULMONARY ARTERIAL HYPERTENSION AND INTERSTITIAL LUNG DISEASE. THE STRUCTURAL INTEGRITY OF ENDOTHELIAL BARRIER IS MAINTAINED BY CYTOSKELETON ELEMENTS, CELL-SUBSTRATE FOCAL ADHESION AND ADHESIVE CELL JUNCTIONS. AGONIST-MEDIATED CHANGES IN ENDOTHELIAL PERMEABILITY ARE DIRECTLY ASSOCIATED WITH REORGANIZATION OF ACTOMYOSIN CYTOSKELETON LEADING TO CELL CONTRACTION AND OPENING OF INTERCELLULAR GAPS OR ENHANCEMENT OF CORTICAL ACTIN CYTOSKELETON ASSOCIATED WITH STRENGTHENING OF ENDOTHELIAL BARRIER. THE ROLE OF ACTIN CYTOSKELETON REMODELING IN ENDOTHELIAL BARRIER REGULATION HAS TAKEN THE CENTRAL STAGE, BUT THE IMPACT OF MICROTUBULES IN THIS PROCESS REMAINS LESS EXPLORED AND UNDER-APPRECIATED. THIS REVIEW WILL SUMMARIZE THE CURRENT KNOWLEDGE ON THE CROSSTALK BETWEEN MICROTUBULES DYNAMICS AND ACTIN CYTOSKELETON REMODELING, DESCRIBE THE SIGNALING MECHANISMS MEDIATING THIS CROSSTALK, DISCUSS EPIGENETIC REGULATION OF MICROTUBULES STABILITY AND ITS NEXUS WITH ENDOTHELIAL BARRIER MAINTENANCE, AND OVERVIEW A ROLE OF MICROTUBULES IN TARGETED DELIVERY OF SIGNALING MOLECULES REGULATING ENDOTHELIAL PERMEABILITY AND INFLAMMATION. 2021