1 6782 89 [CHRONIC DISEASES, PRECANCER, AND CANCER OF THE LUNG, WHICH ARE ASSOCIATED WITH PATHOLOGY OF THE CLUB CELLS OF RESPIRATORY AND TERMINAL BRONCHIOLES]. THE REVIEW OF THE LITERATURE DEALS WITH THE PARTICIPATION OF CLARA CELLS NOW CALLED CLUB CELLS (CCS) OF THE EPITHELIUM IN THE RESPIRATORY AND TERMINAL BRONCHIOLES IN THE PATHOGENESIS AND MORPHOGENESIS OF CHRONIC INFLAMMATORY DISEASES, PRECANCER, AND CANCER OF THE LUNG, WHICH DEVELOP IN THE RESPIRATORY SEGMENTS. THE REVIEW SUMMARIZES DATA ON THE HISTOPHYSIOLOGY OF CCS AND THEIR PARTICIPATION IN THE PATHOGENESIS AND MORPHOGENESIS OF CHRONIC INTERSTITIAL LUNG DISEASES, PNEUMOCONIOSIS, CHRONIC OBSTRUCTIVE DISEASES, ADENOMATOSIS, AND ADENOCARCINOMA OF THE LUNG. IN THIS AREA, THERE IS A BRONCHIOLOALVEOLAR JUNCTION AREA (BAJA), ONE OF THE MOST IMPORTANT STEM CELL NICHES. CCS ARE LOCATED IN THE BAJA; THEY ARE PROGENITOR TISSUE STEM CELLS AND PLAY AN IMPORTANT ROLE IN THE REGENERATION OF THE EPITHELIUM OF THE RESPIRATORY BRONCHIOLES AND ALVEOLI. PATHOLOGY OF CCS IN THE BAJA LEADS TO THE MAINTENANCE OF CHRONIC INFLAMMATION, TO THE DESTRUCTION OF THE LUNG ELASTIC FRAME, AND TO IMPAIRED EPITHELIAL REGENERATION, INTERSTITIAL FIBROSIS, AND ADENOMATOSIS. IN THIS CASE, DECOMPENSATED INFLAMMATION, PATHOLOGICAL REGENERATION, AND FIBROSIS DEVELOP, WHICH, ALONG WITH THE ACTION OF CARCINOGENIC AGENTS, CAN CONTRIBUTE TO THE ACCUMULATION OF MUTATIONS AND EPIGENETIC REARRANGEMENTS IN THE CCS, WHICH SUBSEQUENTLY RESULTS IN ATYPICAL ADENOMATOUS HYPERPLASIA AND ADENOCARCINOMA OF THE LUNG. 2018 2 2020 27 EPIGENETIC CHANGES AND FUNCTIONS IN PNEUMOCONIOSIS. PNEUMOCONIOSIS IS ONE OF THE MOST COMMON OCCUPATIONAL DISEASES IN THE WORLD, AND SPECIFIC TREATMENT METHODS OF PNEUMOCONIOSIS ARE LACKING AT PRESENT, SO IT CARRIES GREAT SOCIAL AND ECONOMIC BURDENS. PNEUMOCONIOSIS, CORONAVIRUS DISEASE 2019, AND IDIOPATHIC PULMONARY FIBROSIS ALL HAVE SIMILAR TYPICAL PATHOLOGICAL CHANGES-PULMONARY FIBROSIS. PULMONARY FIBROSIS IS A CHRONIC LUNG DISEASE CHARACTERIZED BY EXCESSIVE DEPOSITION OF THE EXTRACELLULAR MATRIX AND REMODELING OF THE LUNG TISSUE STRUCTURE. CLARIFYING THE PATHOGENESIS OF PNEUMOCONIOSIS PLAYS AN IMPORTANT GUIDING ROLE IN ITS TREATMENT. THE OCCURRENCE AND DEVELOPMENT OF PNEUMOCONIOSIS ARE ACCOMPANIED BY EPIGENETIC FACTORS (E.G., DNA METHYLATION AND NONCODING RNA) CHANGES, WHICH IN TURN CAN PROMOTE OR INHIBIT THE PROCESS OF PNEUMOCONIOSIS. HERE, WE SUMMARIZE EPIGENETIC CHANGES AND FUNCTIONS IN THE SEVERAL KINDS OF EVIDENCE CLASSIFICATION (EPIDEMIOLOGICAL INVESTIGATION, IN VIVO, AND IN VITRO EXPERIMENTS) AND MAIN TYPES OF CELLS (MACROPHAGES, FIBROBLASTS, AND ALVEOLAR EPITHELIAL CELLS) TO PROVIDE SOME CLUES FOR FINDING SPECIFIC THERAPEUTIC TARGETS FOR PNEUMOCONIOSIS AND EVEN FOR PULMONARY FIBROSIS. 2022 3 5484 29 REVEALING THE PATHOGENIC AND AGING-RELATED MECHANISMS OF THE ENIGMATIC IDIOPATHIC PULMONARY FIBROSIS. AN INTEGRAL MODEL. A GROWING BODY OF EVIDENCE INDICATES THAT ABERRANT ACTIVATION OF ALVEOLAR EPITHELIAL CELLS AND FIBROBLASTS IN AN AGING LUNG PLAYS A CRITICAL ROLE IN THE PATHOGENESIS OF IDIOPATHIC PULMONARY FIBROSIS (IPF). HOWEVER, THE BIOPATHOLOGICAL PROCESSES LINKING AGING WITH IPF AND THE MECHANISMS RESPONSIBLE FOR THE ABNORMAL ACTIVATION OF EPITHELIAL CELLS AND FIBROBLASTS HAVE NOT BEEN ELUCIDATED. MANY OF THE HALLMARKS OF AGING (E.G., GENOMIC INSTABILITY, TELOMERE ATTRITION, EPIGENETIC ALTERATIONS, MITOCHONDRIAL DYSFUNCTION, AND CELLULAR SENESCENCE) HAVE BEEN PROPOSED AS ESSENTIAL MECHANISMS FOR THE DEVELOPMENT OF IPF; HOWEVER, THESE DISTURBANCES ARE NOT RESTRICTED TO IPF AND ALSO OCCUR IN OTHER AGING-RELATED LUNG DISORDERS, PRIMARILY CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). THEREFORE, AN UNANSWERED QUESTION IS WHY A CURRENT/FORMER SMOKER OF ABOUT 60 YEARS OF AGE WITH SHORTER TELOMERES, ALVEOLAR EPITHELIAL SENESCENCE, EXCESSIVE OXIDATIVE STRESS, AND MITOCHONDRIAL DYSFUNCTION DEVELOPS IPF AND NOT COPD; IN OTHER WORDS, WHAT MAKES OLD LUNGS SPECIFICALLY SUSCEPTIBLE TO DEVELOP IPF? IN THIS PERSPECTIVE, WE PROPOSE AN INTEGRAL MODEL IN WHICH THE COMBINATION OF SOME GENE VARIANTS AND/OR GENE EXPRESSION IN THE AGING LUNG RESULTS IN THE LOSS OF EPITHELIAL INTEGRITY AND CONSEQUENTLY IN THE FAILURE OF THE ALVEOLI TO CORRECTLY RESPOND TO INJURY AND TO FACE THE STRESS ASSOCIATED WITH MECHANICAL STRETCH. AFTERWARD, A DISTINCTIVE EPIGENETIC "REPROGRAMMING" THAT AFFECTS BOTH EPITHELIAL CELLS AND FIBROBLASTS PROVOKES, AMONG OTHERS, THE RECAPITULATION OF DEVELOPMENTAL PATHWAYS AND THE ABERRANT ACTIVATION AND MISCOMMUNICATION BETWEEN BOTH CELL TYPES, RESULTING IN THE EXAGGERATED PRODUCTION AND ACCUMULATION OF EXTRACELLULAR MATRIX AND THE SUBSEQUENT DESTRUCTION OF THE LUNG ARCHITECTURE. 2014 4 3512 23 IDIOPATHIC PULMONARY FIBROSIS. IDIOPATHIC PULMONARY FIBROSIS IS A DEVASTATING, AGE-RELATED LUNG DISEASE OF UNKNOWN CAUSE THAT HAS FEW TREATMENT OPTIONS. THIS DISEASE WAS ONCE THOUGHT TO BE A CHRONIC INFLAMMATORY PROCESS, BUT CURRENT EVIDENCE INDICATES THAT THE FIBROTIC RESPONSE IS DRIVEN BY ABNORMALLY ACTIVATED ALVEOLAR EPITHELIAL CELLS (AECS). THESE CELLS PRODUCE MEDIATORS THAT INDUCE THE FORMATION OF FIBROBLAST AND MYOFIBROBLAST FOCI THROUGH THE PROLIFERATION OF RESIDENT MESENCHYMAL CELLS, ATTRACTION OF CIRCULATING FIBROCYTES, AND STIMULATION OF THE EPITHELIAL TO MESENCHYMAL TRANSITION. THE FIBROBLAST AND MYOFIBROBLAST FOCI SECRETE EXCESSIVE AMOUNTS OF EXTRACELLULAR MATRIX, MAINLY COLLAGENS, RESULTING IN SCARRING AND DESTRUCTION OF THE LUNG ARCHITECTURE. THE MECHANISMS THAT LINK IDIOPATHIC PULMONARY FIBROSIS WITH AGEING AND ABERRANT EPITHELIAL ACTIVATION ARE UNKNOWN; EVIDENCE SUGGESTS THAT THE ABNORMAL RECAPITULATION OF DEVELOPMENTAL PATHWAYS AND EPIGENETIC CHANGES HAVE A ROLE. IN THIS SEMINAR, WE REVIEW RECENT DATA ON THE CLINICAL COURSE, THERAPEUTIC OPTIONS, AND UNDERLYING MECHANISMS THOUGHT TO BE INVOLVED IN THE PATHOGENESIS OF IDIOPATHIC PULMONARY FIBROSIS. 2011 5 3674 21 INFLAMMATION AND DYSREGULATED FIBROBLAST PROLIFERATION--NEW MECHANISMS? IDIOPATHIC PULMONARY FIBROSIS (IPF) IS A DEVASTATING, AGE-RELATED LUNG DISEASE OF UNKNOWN CAUSE THAT HAS FEW TREATMENT OPTIONS. ONCE THOUGHT TO BE A CHRONIC INFLAMMATORY PROCESS, CURRENT EVIDENCE INDICATES THAT THE FIBROTIC RESPONSE MAY PRIMARILY BE DRIVEN BY ABNORMALLY ACTIVATED ALVEOLAR EPITHELIAL CELLS AND THE UNDERLYING MESENCHYME. THE MEDIATORS PRODUCED AND PRESENT IN THIS MICROENVIRONMENT INDUCE THE FORMATION OF FIBROBLAST FOCI THROUGH THE PROLIFERATION OF RESIDENT MESENCHYMAL CELLS, ATTRACTION OF CIRCULATING FIBROCYTES, AND STIMULATION OF EPITHELIAL TO MESENCHYMAL TRANSITION. THE FIBROBLAST AND MYOFIBROBLAST FOCI SECRETE EXCESSIVE AMOUNTS OF EXTRACELLULAR MATRIX, MAINLY COLLAGENS, RESULTING IN SCARRING AND DESTRUCTION OF THE LUNG ARCHITECTURE. THE DETAILED MECHANISMS THAT LINK IPF WITH AGEING AND ABERRANT EPITHELIAL ACTIVATION ARE UNKNOWN, BUT SOME EVIDENCE SUGGESTS THAT THE ABNORMAL RECAPITULATION OF DEVELOPMENTAL PATHWAYS AND EPIGENETIC CHANGES MAY PLAY A ROLE. THIS REVIEW PROVIDES A BRIEF SYNOPSIS OF HIGHLIGHTS IN THE CURRENT UNDERSTANDING OF THE PATHOPHYSIOLOGY OF IPF, AS WELL AS NOVEL THERAPEUTICS BEING EXPLORED IN CLINICAL TRIALS FOR THE TREATMENT OF THIS DEVASTATING DISEASE. 2013 6 4954 20 PATHOGENESIS OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE. THE PATHOGENESIS OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) ENCOMPASSES A NUMBER OF INJURIOUS PROCESSES, INCLUDING AN ABNORMAL INFLAMMATORY RESPONSE IN THE LUNGS TO INHALED PARTICLES AND GASES. OTHER PROCESSES, SUCH AS FAILURE TO RESOLVE INFLAMMATION, ABNORMAL CELL REPAIR, APOPTOSIS, ABNORMAL CELLULAR MAINTENANCE PROGRAMS, EXTRACELLULAR MATRIX DESTRUCTION (PROTEASE/ANTIPROTEASE IMBALANCE), AND OXIDATIVE STRESS (OXIDANT/ANTIOXIDANT IMBALANCE) ALSO HAVE A ROLE. THE INFLAMMATORY RESPONSES TO THE INHALATION OF ACTIVE AND PASSIVE TOBACCO SMOKE AND URBAN AND RURAL AIR POLLUTION ARE MODIFIED BY GENETIC AND EPIGENETIC FACTORS. THE SUBSEQUENT CHRONIC INFLAMMATORY RESPONSES LEAD TO MUCUS HYPERSECRETION, AIRWAY REMODELING, AND ALVEOLAR DESTRUCTION. THIS ARTICLE PROVIDES AN UPDATE ON THE CELLULAR AND MOLECULAR MECHANISMS OF THESE PROCESSES IN THE PATHOGENESIS OF COPD. 2007 7 6053 22 THE CRUCIAL ROLE OF NLRP3 INFLAMMASOME IN VIRAL INFECTION-ASSOCIATED FIBROSING INTERSTITIAL LUNG DISEASES. IDIOPATHIC PULMONARY FIBROSIS (IPF), ONE OF THE MOST COMMON FIBROSING INTERSTITIAL LUNG DISEASES (ILD), IS A CHRONIC-AGE-RELATED RESPIRATORY DISEASE THAT RISES FROM REPEATED MICRO-INJURY OF THE ALVEOLAR EPITHELIUM. ENVIRONMENTAL INFLUENCES, INTRINSIC FACTORS, GENETIC AND EPIGENETIC RISK FACTORS THAT LEAD TO CHRONIC INFLAMMATION MIGHT BE IMPLICATED IN THE DEVELOPMENT OF IPF. THE EXACT TRIGGERS THAT INITIATE THE FIBROTIC RESPONSE IN IPF REMAIN ENIGMATIC, BUT THERE IS NOW INCREASING EVIDENCE SUPPORTING THE ROLE OF CHRONIC EXPOSURE OF VIRAL INFECTION. DURING VIRAL INFECTION, ACTIVATION OF THE NLRP3 INFLAMMASOME BY INTEGRATING MULTIPLE CELLULAR AND MOLECULAR SIGNALING IMPLICATES ROBUST INFLAMMATION, FIBROBLAST PROLIFERATION, ACTIVATION OF MYOFIBROBLAST, MATRIX DEPOSITION, AND ABERRANT EPITHELIAL-MESENCHYMAL FUNCTION. OVERALL, THE CROSSTALK OF THE NLRP3 INFLAMMASOME AND VIRUSES CAN ACTIVATE IMMUNE RESPONSES AND INFLAMMASOME-ASSOCIATED MOLECULES IN THE DEVELOPMENT, PROGRESSION, AND EXACERBATION OF IPF. 2021 8 182 20 ACCELERATED LUNG AGING AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE. THE PREVALENCE OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) INCREASES EXPONENTIALLY WITH AGING. ITS PATHOGENESIS, HOWEVER, IS NOT WELL KNOWN AND ASIDE FROM SMOKING CESSATION, THERE ARE NO DISEASE-MODIFYING TREATMENTS FOR THIS DISEASE. AREAS COVERED: COPD IS ASSOCIATED WITH ACCELERATING AGING AND AGING-RELATED DISEASES. IN THIS REVIEW, WE WILL DISCUSS THE HALLMARKS OF AGING INCLUDING GENOMIC INSTABILITY, TELOMERE ATTRITION, EPIGENETIC ALTERATION, LOSS OF PROTEOSTASIS, MITOCHONDRIAL DYSFUNCTION, DEREGULATED NUTRIENT SENSING, CELLULAR SENESCENCE, STEM CELL EXHAUSTION, AND ALTERED INTERCELLULAR COMMUNICATION, WHICH MAY BE INVOLVED IN COPD PATHOGENESIS. EXPERT COMMENTARY: COPD AND THE AGING PROCESS SHARE SIMILAR MOLECULAR AND CELLULAR CHANGES. AGING-RELATED MOLECULAR PATHWAYS MAY REPRESENT NOVEL THERAPEUTIC TARGETS AND BIOMARKERS FOR COPD. 2019 9 3514 30 IDIOPATHIC PULMONARY FIBROSIS: PATHOGENESIS AND THERAPEUTIC APPROACHES. IDIOPATHIC PULMONARY FIBROSIS (IPF), ALSO TERMED CRYPTOGENIC FIBROSING ALVEOLITIS, IS A CLINICOPATHOLOGICAL SYNDROME CHARACTERISED BY COUGH, EXERTIONAL DYSPNEOA, BASILAR CRACKLES, A RESTRICTIVE DEFECT ON PULMONARY FUNCTION TESTS, HONEYCOMBING ON HIGH-RESOLUTION, THIN-SECTION COMPUTED TOMOGRAPHIC SCANS AND THE HISTOLOGICAL DIAGNOSIS OF USUAL INTERSTITIAL PNEUMONIA ON LUNG BIOPSY. THE COURSE IS USUALLY INDOLENT BUT INEXORABLE. MOST PATIENTS DIE OF PROGRESSIVE RESPIRATORY FAILURE WITHIN 3-8 YEARS OF THE ONSET OF SYMPTOMS. CURRENT THERAPIES ARE OF UNPROVEN BENEFIT. ALTHOUGH THE PATHOGENESIS OF IPF HAS NOT BEEN ELUCIDATED, EARLY CONCEPTS FOCUSED ON LUNG INJURY LEADING TO A CYCLE OF CHRONIC ALVEOLAR INFLAMMATION EVENTUATING IN FIBROSIS AND DESTRUCTION OF THE LUNG ARCHITECTURE. ANTI-INFLAMMATORY THERAPIES EMPLOYING CORTICOSTEROIDS OR IMMUNOSUPPRESSIVE OR CYTOTOXIC AGENTS HAVE BEEN DISAPPOINTING. MORE RECENT HYPOTHESES ACKNOWLEDGE THAT SEQUENTIAL ALVEOLAR EPITHELIAL CELL INJURY IS LIKELY TO BE A KEY EVENT IN THE PATHOGENESIS OF IPF, BUT THE CARDINAL EVENT IS AN ABERRANT HOST RESPONSE TO WOUND HEALING. IN THIS CONTEXT, ABNORMAL EPITHELIAL-MESENCHYMAL INTERACTIONS, ALTERED FIBROBLAST PHENOTYPES, EXAGGERATED FIBROBLAST PROLIFERATION, AND EXCESSIVE DEPOSITION OF COLLAGEN AND EXTRACELLULAR MATRIX ARE PIVOTAL TO THE FIBROTIC PROCESS. SEVERAL CLINICAL TRIALS ARE CURRENTLY UNDERWAY OR IN THE PLANNING STAGES, AND INCLUDE DRUGS SUCH AS INTERFERON-GAMMA 1B, PIRFENIDONE, ACETYLCYSTEINE, ETANERCEPT (A TUMOR NECROSIS FACTOR-ALPHA ANTAGONIST), BOSENTAN (AN ENDOTHELIN-1 RECEPTOR ANTAGONIST) AND ZILEUTON (A 5-LYPOXYGENASE INHIBITOR). FUTURE THERAPEUTIC STRATEGIES SHOULD BE FOCUSED ON ALVEOLAR EPITHELIAL CELLS AIMED AT ENHANCING RE-EPITHELIALISATION AND ON FIBROBLASTIC/MYOFIBROBLASTIC FOCI, WHICH PLAY AN ESSENTIAL ROLE IN THE DEVELOPMENT OF IPF. STEM CELL PROGENITORS OF THE ALVEOLAR EPITHELIAL CELLS AND GENETIC AND EPIGENETIC THERAPIES ARE ATTRACTIVE FUTURE APPROACHES FOR THIS AND OTHER FIBROTIC LUNG DISORDERS. 2004 10 6223 26 THE LEADING ROLE OF EPITHELIAL CELLS IN THE PATHOGENESIS OF IDIOPATHIC PULMONARY FIBROSIS. IDIOPATHIC PULMONARY FIBROSIS (IPF) IS A RELENTLESSLY PROGRESSIVE AND DEVASTATING INTERSTITIAL LUNG DISEASE OF UNKNOWN ETIOLOGY, WHERE THE NORMAL LUNG ARCHITECTURE IS LOST AND REPLACED BY FIBROTIC TISSUE LEADING TO AN IRREVERSIBLE AND PROGRESSIVE RESPIRATORY INSUFFICIENCY. HISTORICALLY, IPF WAS CONSIDERED A CHRONIC INFLAMMATORY DISORDER, WHICH GRADUALLY PROGRESSED TO ESTABLISHED FIBROSIS. HOWEVER, STRONG CLINICAL AND EXPERIMENTAL EVIDENCE INDICATES THAT THE DISEASE REPRESENTS AN EPITHELIAL-DRIVEN DISORDER WHICH RESULTS FROM A COMPLEX INTERPLAY OF GENETIC AND ENVIRONMENTAL RISK FACTORS, AGING-ASSOCIATED PROCESSES AND A PROFIBROTIC EPIGENETIC REPROGRAMMING. THE CONVERGENCE OF THESE FACTORS RESULTS IN THE ABERRANT ACTIVATION OF EPITHELIAL CELLS THAT INITIATE THE DEVELOPMENT OF THE DISEASE, PRODUCING VIRTUALLY ALL THE MEDIATORS THAT PARTICIPATE IN THE MIGRATION, PROLIFERATION AND ACTIVATION OF FIBROBLASTS, THEIR DIFFERENTIATION TO MYOFIBROBLASTS AND THE EXCESSIVE AND CHAOTIC SECRETION OF EXTRACELLULAR MATRIX PROTEINS. ALTHOUGH PROGRESS HAS BEEN MADE IN UNDERSTANDING THE CAUSES AND CONSEQUENCES OF THIS ABNORMAL BEHAVIOR OF DISTAL AIRWAYS AND ALVEOLAR EPITHELIUM, THE MECHANISMS THAT INITIATE AND PERPETUATE THE VICIOUS CIRCLE OF MULTIDIRECTIONAL ABNORMAL COMMUNICATIONS BETWEEN THE EPITHELIUM AND FIBROBLASTS AND OTHER RESIDENT CELLS HAVE NOT BEEN ELUCIDATED. IN THIS REVIEW, WE DISCUSS THE ROLE OF EPITHELIAL CELLS AND THE MECHANISMS UNDERLYING THE FIBROTIC RESPONSE IN IPF, AND HIGHLIGHT SOME PROMISING THERAPEUTIC TARGETS FOR THESE CELLS. 2020 11 3181 16 HALLMARKS OF AGING: AN EXPANDING UNIVERSE. AGING IS DRIVEN BY HALLMARKS FULFILLING THE FOLLOWING THREE PREMISES: (1) THEIR AGE-ASSOCIATED MANIFESTATION, (2) THE ACCELERATION OF AGING BY EXPERIMENTALLY ACCENTUATING THEM, AND (3) THE OPPORTUNITY TO DECELERATE, STOP, OR REVERSE AGING BY THERAPEUTIC INTERVENTIONS ON THEM. WE PROPOSE THE FOLLOWING TWELVE HALLMARKS OF AGING: GENOMIC INSTABILITY, TELOMERE ATTRITION, EPIGENETIC ALTERATIONS, LOSS OF PROTEOSTASIS, DISABLED MACROAUTOPHAGY, DEREGULATED NUTRIENT-SENSING, MITOCHONDRIAL DYSFUNCTION, CELLULAR SENESCENCE, STEM CELL EXHAUSTION, ALTERED INTERCELLULAR COMMUNICATION, CHRONIC INFLAMMATION, AND DYSBIOSIS. THESE HALLMARKS ARE INTERCONNECTED AMONG EACH OTHER, AS WELL AS TO THE RECENTLY PROPOSED HALLMARKS OF HEALTH, WHICH INCLUDE ORGANIZATIONAL FEATURES OF SPATIAL COMPARTMENTALIZATION, MAINTENANCE OF HOMEOSTASIS, AND ADEQUATE RESPONSES TO STRESS. 2023 12 290 22 AGING AND PULMONARY FIBROSIS. IDIOPATHIC PULMONARY FIBROSIS IS A CHRONIC, PROGRESSIVE, AND USUALLY FATAL LUNG DISORDER OF UNKNOWN ETIOLOGY. THE DISEASE LIKELY RESULTS FROM THE INTERACTION OF GENETIC SUSCEPTIBILITY ARCHITECTURE, ENVIRONMENTAL FACTORS SUCH AS SMOKING, AND AN ABNORMAL EPIGENETIC REPROGRAMMING THAT LEADS TO A COMPLEX PATHOGENESIS. IDIOPATHIC PULMONARY FIBROSIS OCCURS IN MIDDLE-AGED AND MAINLY ELDERLY ADULTS, AND IN THIS CONTEXT AGE HAS EMERGED AS ITS STRONGEST RISK FACTOR. HOWEVER, THE MECHANISMS LINKING IT TO AGING ARE UNCERTAIN. RECENTLY, NINE MOLECULAR AND CELLULAR HALLMARKS OF AGING HAVE BEEN PROPOSED: GENOMIC INSTABILITY, TELOMERE ATTRITION, EPIGENETIC ALTERATIONS, LOSS OF PROTEOSTASIS, DEREGULATED NUTRIENT SENSING, MITOCHONDRIAL DYSFUNCTION, CELLULAR SENESCENCE, STEM CELL EXHAUSTION, AND ALTERED INTERCELLULAR COMMUNICATION. IN THIS REVIEW, WE PROVIDE AN OVERVIEW OF THESE MOLECULAR MECHANISMS AND THEIR INVOLVEMENT IN THE PATHOGENESIS OF IDIOPATHIC PULMONARY FIBROSIS, WHILE EMPHASIZING THAT THE STUDIES ON THIS DISEASE ARE FEW AND THE FINDINGS ARE NOT DEFINITIVE. 2016 13 6212 22 THE INTERPLAY OF THE GENETIC ARCHITECTURE, AGING, AND ENVIRONMENTAL FACTORS IN THE PATHOGENESIS OF IDIOPATHIC PULMONARY FIBROSIS. IDIOPATHIC PULMONARY FIBROSIS (IPF) IS A CHRONIC FIBROSING LUNG DISEASE OF INDETERMINATE ETIOLOGY AND LIMITED THERAPEUTIC OPTIONS. THE INITIATION, DEVELOPMENT, AND PROGRESSION OF IPF ARE INFLUENCED BY GENETIC PREDISPOSITION, AGING, AND HOST AND ENVIRONMENTAL FACTORS, BUT THE MAGNITUDE OF THE CONTRIBUTION OF EACH OF THEM AND THE SEQUENCE OF THE PATHOGENIC EVENTS ARE UNCERTAIN. CURRENT EVIDENCE INDICATES THAT ACCUMULATED ENVIRONMENTAL EXPOSURES IN A GENETICALLY PREDISPOSED INDIVIDUAL, USUALLY OVER 60 YEARS OF AGE, LEADS TO PHENOTYPIC AND FUNCTIONAL ALTERATIONS OF THE LUNG EPITHELIUM. ABERRANT ACTIVATION OF EPITHELIAL CELLS RESULTS, THROUGH A COMPLEX RELEASE OF NUMEROUS MEDIATORS, IN THE LOCAL EXPANSION OF PECULIAR SUBSETS OF AGGRESSIVE FIBROBLASTS AND MYOFIBROBLASTS, WHICH ARE CRUCIAL EFFECTOR CELLS OF FIBROTIC REMODELING AND LOSS OF THE NORMAL LUNG ARCHITECTURE AND FUNCTION. PROGRESSIVE INCREASE OF THE MECHANICAL STIFFNESS ACTIVATES CELL-AUTONOMOUS AND MATRIX-DEPENDENT PROCESSES CONTRIBUTING TO THE PERPETUATION OF THE FIBROTIC RESPONSE. THIS PERSPECTIVE PROVIDES AN INTEGRAL OVERVIEW OF THE MAJOR RISK FACTORS UNDERPINNING THE PATHOGENESIS OF IPF, INCLUDING GENE VARIANTS, AGING ALTERATIONS, ENVIRONMENTAL FACTORS, HOST RISK FACTORS, AND EPIGENETIC REPROGRAMMING. 2021 14 5322 21 PULMONARY DISEASES AND AGEING. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) AND IDIOPATHIC PULMONARY FIBROSIS ARE REGARDED AS A DISEASES OF ACCELERATED LUNG AGEING AND SHOW ALL OF THE HALLMARKS OF AGEING, INCLUDING TELOMERE SHORTENING, CELLULAR SENESCENCE, ACTIVATION OF PI3 KINASE-MTOR SIGNALING, IMPAIRED AUTOPHAGY, MITOCHONDRIAL DYSFUNCTION, STEM CELL EXHAUSTION, EPIGENETIC CHANGES, ABNORMAL MICRORNA PROFILES, IMMUNOSENESCENCE AND A LOW GRADE CHRONIC INFLAMMATION DUE TO SENESCENCE-ASSOCIATED SECRETORY PHENOTYPE (SASP). MANY OF THESE AGEING MECHANISMS ARE DRIVEN BY EXOGENOUS AND ENDOGENOUS OXIDATIVE STRESS. THERE IS ALSO A REDUCTION IN ANTI-AGEING MOLECULES, SUCH AS SIRTUINS AND KLOTHO, WHICH FURTHER ACCELERATE THE AGEING PROCESS. UNDERSTANDING THESE MOLECULAR MECHANISMS HAS IDENTIFIED SEVERAL NOVEL THERAPEUTIC TARGETS AND SEVERAL DRUGS AND DIETARY INTERVENTIONS ARE NOW IN DEVELOPMENT TO TREAT CHRONIC LUNG DISEASE. 2019 15 5916 21 TARGETING AGING PATHWAYS IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) HAS BECOME A GLOBAL EPIDEMIC AND IS THE THIRD LEADING CAUSE OF DEATH WORLDWIDE. COPD IS CHARACTERIZED BY CHRONIC AIRWAY INFLAMMATION, LOSS OF ALVEOLAR-CAPILLARY UNITS, AND PROGRESSIVE DECLINE IN LUNG FUNCTION. MAJOR RISK FACTORS FOR COPD ARE CIGARETTE SMOKING AND AGING. COPD-ASSOCIATED PATHOMECHANISMS INCLUDE MULTIPLE AGING PATHWAYS SUCH AS TELOMERE ATTRITION, EPIGENETIC ALTERATIONS, ALTERED NUTRIENT SENSING, MITOCHONDRIAL DYSFUNCTION, CELL SENESCENCE, STEM CELL EXHAUSTION AND CHRONIC INFLAMMATION. IN THIS REVIEW, WE WILL HIGHLIGHT THE CURRENT LITERATURE THAT FOCUSES ON THE ROLE OF AGE AND AGING-ASSOCIATED SIGNALING PATHWAYS AS WELL AS THEIR IMPACT ON CURRENT TREATMENT STRATEGIES IN THE PATHOGENESIS OF COPD. FURTHERMORE, WE WILL DISCUSS ESTABLISHED AND EXPERIMENTAL COPD TREATMENTS INCLUDING SENOLYTIC AND ANTI-AGING THERAPIES AND THEIR POTENTIAL USE AS NOVEL TREATMENT STRATEGIES IN COPD. 2020 16 2169 23 EPIGENETIC MECHANISMS IN PARENCHYMAL LUNG DISEASES: BYSTANDERS OR THERAPEUTIC TARGETS? EPIGENETIC RESPONSES DUE TO ENVIRONMENTAL CHANGES ALTER CHROMATIN STRUCTURE, WHICH IN TURN MODIFIES THE PHENOTYPE, GENE EXPRESSION PROFILE, AND ACTIVITY OF EACH CELL TYPE THAT HAS A ROLE IN THE PATHOPHYSIOLOGY OF A DISEASE. PULMONARY DISEASES ARE ONE OF THE MAJOR CAUSES OF DEATH IN THE WORLD, INCLUDING LUNG CANCER, IDIOPATHIC PULMONARY FIBROSIS (IPF), CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD), PULMONARY HYPERTENSION (PH), LUNG TUBERCULOSIS, PULMONARY EMBOLISM, AND ASTHMA. SEVERAL LINES OF EVIDENCE INDICATE THAT EPIGENETIC MODIFICATIONS MAY BE ONE OF THE MAIN FACTORS TO EXPLAIN THE INCREASING INCIDENCE AND PREVALENCE OF LUNG DISEASES INCLUDING IPF AND COPD. INTERESTINGLY, ISOLATED FIBROBLASTS AND SMOOTH MUSCLE CELLS FROM PATIENTS WITH PULMONARY DISEASES SUCH AS IPF AND PH THAT WERE CULTURED EX VIVO MAINTAINED THE DISEASE PHENOTYPE. THE CELLS OFTEN SHOW A HYPER-PROLIFERATIVE, APOPTOSIS-RESISTANT PHENOTYPE WITH INCREASED EXPRESSION OF EXTRACELLULAR MATRIX (ECM) AND ACTIVATED FOCAL ADHESIONS SUGGESTING THE PRESENCE OF AN EPIGENETICALLY IMPRINTED PHENOTYPE. MOREOVER, MANY ABNORMALITIES OBSERVED IN MOLECULAR PROCESSES IN IPF PATIENTS ARE SHOWN TO BE EPIGENETICALLY REGULATED, SUCH AS INNATE IMMUNITY, CELLULAR SENESCENCE, AND APOPTOTIC CELL DEATH. DNA METHYLATION, HISTONE MODIFICATION, AND MICRORNA REGULATION CONSTITUTE THE MOST COMMON EPIGENETIC MODIFICATION MECHANISMS. 2022 17 5575 23 ROLE OF MICRORNAS IN SIGNALING PATHWAYS ASSOCIATED WITH THE PATHOGENESIS OF IDIOPATHIC PULMONARY FIBROSIS: A FOCUS ON EPITHELIAL-MESENCHYMAL TRANSITION. IDIOPATHIC PULMONARY FIBROSIS (IPF) IS A CHRONIC AND PROGRESSIVE DISEASE WITH HIGH MORTALITY AND UNCLEAR ETIOLOGY. PREVIOUS EVIDENCE SUPPORTS THAT THE ORIGIN OF THIS DISEASE IS ASSOCIATED WITH EPIGENETIC ALTERATIONS, AGE, AND ENVIRONMENTAL FACTORS. IPF INITIATES WITH CHRONIC EPITHELIAL LUNG INJURIES, FOLLOWED BY BASAL MEMBRANE DESTRUCTION, WHICH PROMOTES THE ACTIVATION OF MYOFIBROBLASTS AND EXCESSIVE SYNTHESIS OF EXTRACELLULAR MATRIX (ECM) PROTEINS, AS WELL AS EPITHELIAL-MESENCHYMAL TRANSITION (EMT). DUE TO MIRNAS' ROLE AS REGULATORS OF APOPTOSIS, PROLIFERATION, DIFFERENTIATION, AND CELL-CELL INTERACTION PROCESSES, SOME STUDIES HAVE INVOLVED MIRNAS IN THE BIOGENESIS AND PROGRESSION OF IPF. IN THIS CONTEXT, THE ANALYSIS AND DISCUSSION OF THE PROBABLE ASSOCIATION OF MIRNAS WITH THE SIGNALING PATHWAYS INVOLVED IN THE DEVELOPMENT OF IPF WOULD IMPROVE OUR KNOWLEDGE OF THE ASSOCIATED MOLECULAR MECHANISMS, THEREBY FACILITATING ITS EVALUATION AS A THERAPEUTIC TARGET FOR THIS SEVERE LUNG DISEASE. IN THIS WORK, THE MOST RECENT PUBLICATIONS EVALUATING THE ROLE OF MIRNAS AS REGULATORS OR ACTIVATORS OF SIGNAL PATHWAYS ASSOCIATED WITH THE PATHOGENESIS OF IPF WERE ANALYZED. THE SEARCH IN PUBMED WAS MADE USING THE FOLLOWING TERMS: "MIRNAS AND IDIOPATHIC PULMONARY FIBROSIS (IPF)"; "MIRNAS AND IPF AND SIGNALING PATHWAYS (SP)"; AND "MIRNAS AND IPF AND SP AND IPF PATHOGENESIS". ADDITIONALLY, WE FOCUS MAINLY ON THOSE WORKS WHERE THE SIGNALING PATHWAYS INVOLVED WITH EMT, FIBROBLAST DIFFERENTIATION, AND SYNTHESIS OF ECM COMPONENTS WERE ASSESSED. FINALLY, THE IMPORTANCE AND SIGNIFICANCE OF MIRNAS AS POTENTIAL THERAPEUTIC OR DIAGNOSTIC TOOLS FOR THE TREATMENT OF IPF ARE DISCUSSED. 2022 18 763 22 CAUSES OF PULMONARY FIBROSIS IN THE ELDERLY. IDIOPATHIC PULMONARY FIBROSIS (IPF) IS THE MOST COMMON AND MOST LETHAL TYPE OF IDIOPATHIC INTERSTITIAL PNEUMONIA. IT IS A CHRONIC, AGING-ASSOCIATED LUNG DISEASE CHARACTERIZED BY FIBROTIC FOCI AND INFLAMMATORY INFILTRATES, WITH NO CURE AND VERY LIMITED THERAPEUTIC OPTIONS. ALTHOUGH ITS ETIOLOGY IS UNKNOWN, SEVERAL PATHOGENIC PATHWAYS HAVE BEEN DESCRIBED THAT COULD EXPLAIN THIS PROCESS, INVOLVING AGING, ENVIRONMENTAL FACTORS, GENOMIC INSTABILITY, LOSS OF PROTEOSTASIS, TELOMERE ATTRITION, EPIGENETIC CHANGES, MITOCHONDRIAL DYSFUNCTION, CELL SENESCENCE, AND ALTERED INTERCELLULAR COMMUNICATION. ONE OF THE MAIN PROGNOSTIC FACTORS FOR THE DEVELOPMENT OF IPF IN BROAD EPIDEMIOLOGICAL STUDIES IS AGE. THE INCIDENCE INCREASES WITH AGE, MAKING THIS A DISEASE THAT PREDOMINANTLY AFFECTS THE ELDERLY POPULATION, BEING EXCEPTIONAL UNDER 45 YEARS OF AGE. HOWEVER, THE DEGREE TO WHICH EACH OF THESE MECHANISMS IS INVOLVED IN THE ETIOLOGY OF THE UNCONTROLLED FIBROGENESIS THAT DEFINES IPF IS STILL UNKNOWN. CLARIFYING THESE QUESTIONS IS CRUCIAL TO THE DEVELOPMENT OF POINTS OF INTERVENTION IN THE PATHOGENESIS OF THE DISEASE. THIS REVIEW BRIEFLY SUMMARIZES WHAT IS KNOWN ABOUT EACH POSSIBLE ETIOLOGICAL FACTOR, AND THE QUESTIONS THAT MOST URGENTLY NEED TO BE ADDRESSED. 2018 19 292 28 AGING AND SUSCEPTIBILITY TO PULMONARY DISEASE. THE LUNGS ARE CONTINUALLY SUBJECTED TO NOXIOUS AND INERT SUBSTANCES, ARE IMMUNOLOGICALLY ACTIVE, AND ARE IN A CONSTANT STATE OF DAMAGE AND REPAIR. THIS MAKES THE PULMONARY SYSTEM PARTICULARLY VULNERABLE TO DISEASES OF AGING. AGING CAN BE UNDERSTOOD AS RANDOM MOLECULAR DAMAGE THAT IS UNREPAIRED AND ACCUMULATES OVER TIME, RESULTING IN CELLULAR DEFECTS AND TISSUE DYSFUNCTION. THE BREAKDOWN OF CELLULAR MECHANISMS, INCLUDING STEM CELL EXHAUSTION, GENOMIC INSTABILITY, TELOMERE ATTRITION, EPIGENETIC ALTERATION, LOSS OF PROTEOSTASIS, DEREGULATED NUTRIENT SENSING, MITOCHONDRIAL DYSFUNCTION, CELLULAR SENESCENCE, ALTERED INTERCELLULAR COMMUNICATION, AND CHANGES IN THE EXTRACELLULAR MATRIX IS THOUGHT TO ADVANCE THE AGING PROCESS ITSELF. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD), IDIOPATHIC PULMONARY FIBROSIS (IPF), AND CANCERS ILLUSTRATE A PATHOLOGIC BREAKDOWN IN THESE MECHANISMS BEYOND NORMAL AGING. THE IMMUNE SYSTEM BECOMES LESS EFFECTIVE WITH ADVANCING AGE. THERE IS A LOW-LEVEL STATE OF CHRONIC INFLAMMATION TERMED INFLAMMAGING WHICH IS THOUGHT TO BE DRIVEN BY IMMUNOSENESCENCE, THE CHANGES IN THE INNATE AND ADAPTIVE IMMUNE SYSTEMS WITH ADVANCING AGE THAT LEAD TO DYSREGULATION AND DECREASED EFFECTIVENESS OF THE IMMUNE SYSTEM. THESE PROCESSES OF AGING LEAD TO EXPECTED CHANGES IN THE FORM AND FUNCTION OF THE RESPIRATORY SYSTEM, MOST NOTABLY A LOSS OF LUNG ELASTICITY, DECREASE IN RESPIRATORY MUSCLE STRENGTH, INCREASE IN VENTILATION-PERFUSION MISMATCHING, AND STIFFENING OF THE VASCULATURE. THE ASTUTE CLINICIAN IS AWARE OF THESE EXPECTED FINDINGS AND DOES NOT OFTEN ATTRIBUTE DYSPNEA TO AGING ALONE. MAINTAINING A LOW THRESHOLD TO INVESTIGATE FOR COMORBID DISEASE AND UNDERSTANDING HOW PULMONARY DISEASE PRESENTS DIFFERENTLY IN THE ELDERLY THAN IN YOUNGER ADULTS CAN IMPROVE CLINICAL OUTCOMES. (C) 2022 AMERICAN PHYSIOLOGICAL SOCIETY. COMPR PHYSIOL 12:3509-3522, 2022. 2022 20 756 23 CARM1 REGULATES SENESCENCE DURING AIRWAY EPITHELIAL CELL INJURY IN COPD PATHOGENESIS. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) IS A LIFE-THREATENING LUNG DISEASE. ALTHOUGH CIGARETTE SMOKE WAS CONSIDERED THE MAIN CAUSE OF DEVELOPMENT, THE HETEROGENEOUS NATURE OF THE DISEASE LEAVES IT UNCLEAR WHETHER OTHER FACTORS CONTRIBUTE TO THE PREDISPOSITION OR IMPAIRED REGENERATION RESPONSE OBSERVED. RECENTLY, EPIGENETIC MODIFICATION HAS EMERGED TO BE A KEY PLAYER IN THE PATHOGENESIS OF COPD. THE ADDITION OF METHYL GROUPS TO ARGININE RESIDUES IN BOTH HISTONE AND NONHISTONE PROTEINS BY PROTEIN ARGININE METHYLTRANSFERASES (PRMTS) IS AN IMPORTANT POSTTRANSLATIONAL EPIGENETIC MODIFICATION EVENT REGULATING CELLULAR PROLIFERATION, DIFFERENTIATION, APOPTOSIS, AND SENESCENCE. HERE, WE HYPOTHESIZE THAT COACTIVATOR-ASSOCIATED ARGININE METHYLTRANSFERASE-1 (CARM1) REGULATES AIRWAY EPITHELIAL CELL INJURY IN COPD PATHOGENESIS BY CONTROLLING CELLULAR SENESCENCE. USING THE NAPHTHALENE (NA)-INDUCED MOUSE MODEL OF AIRWAY EPITHELIAL DAMAGE, WE DEMONSTRATE THAT LOSS OF CC10-POSITIVE CLUB CELLS IS ACCOMPANIED BY A REDUCTION IN CARM1-EXPRESSING CELLS OF THE AIRWAY EPITHELIUM. FURTHERMORE, CARM1 HAPLOINSUFFFICENT MICE SHOWED PERTURBED CLUB CELL REGENERATION FOLLOWING NA TREATMENT. IN ADDITION, CARM1 REDUCTION LED TO DECREASED NUMBERS OF ANTISENESCENT SIRTUIN 1-EXPRESSING CELLS ACCOMPANIED BY HIGHER P21, P16, AND BETA-GALACTOSIDASE-POSITIVE SENESCENT CELLS IN THE MOUSE AIRWAY FOLLOWING NA TREATMENT. IMPORTANTLY, CARM1-SILENCED HUMAN BRONCHIAL EPITHELIAL CELLS SHOWED IMPAIRED WOUND HEALING AND HIGHER BETA-GALACTOSIDASE ACTIVITY. THESE RESULTS DEMONSTRATE THAT CARM1 CONTRIBUTES TO AIRWAY REPAIR AND REGENERATION BY REGULATING AIRWAY EPITHELIAL CELL SENESCENCE. 2019