PubMed HealthSearch

SEARCH · PubMed Health

Results for “regeneration program”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Sustained NF-κB activation allows mutant alveolar stem cells to co-opt a regeneration program for tumor initiation.

Disruptions to regulatory signals governing stem cell fate open the pathway to tumorigenesis. To determine how these programs become destabilized, we fate-map thousands of murine wild-type and KrasG12D-mutant alveolar type II (AT2) stem cells in vivo and find evidence for two independent AT2 subpopulations marked by distinct tumorigenic capacities. By combining clonal analyses with single-cell transcriptomics, we unveil striking parallels between lung regeneration and tumorigenesis that implicate Il1r1 as a common activator of AT2 reprogramming. We show that tumor evolution proceeds through the acquisition of lineage infidelity and reversible transitions between mutant states, which, in turn, modulate wild-type AT2 dynamics. Finally, we discover how sustained nuclear factor κB (NF-κB) activation sets tumorigenesis apart from regeneration, allowing mutant cells to subvert differentiation in favor of tumor growth.

Animals

Integrative analysis of transcriptome and DNA methylome dynamics during caudal fin regeneration in silver pomfret (Pampus argenteus).

Caudal fin regeneration in teleost fish is a complex, multi-stage process involving coordinated molecular and cellular changes. While the role of epigenetic regulation particularly DNA methylation has been studied in model freshwater species such as zebrafish, its contribution to regeneration in marine teleosts remains largely unexplored. In this study, we integrated transcriptomic and DNA methylomic data to characterize the temporal dynamics of gene expression and methylation during caudal fin regeneration in the silver pomfret (Pampus argenteus). Using RNA-sequencing and reduced representation bisulfite sequencing (RRBS) at three biologically critical time points 1, 3, and 7 days post-amputation (dpa), we characterized the spatiotemporal molecular landscape of caudal fin regeneration. These time points capture the key transitional phases of wound healing and inflammation (1 dpa), blastema formation and progenitor proliferation (3 dpa), and regenerative outgrowth with tissue remodeling (7 dpa), enabling robust detection of the major molecular programs underlying epimorphic regeneration. Concurrently, CG-methylome analysis identified thousands of dynamically changing differentially methylated regions (DMRs). A strong global inverse correlation was observed between promoter methylation and gene expression. Integrative analysis pinpointed key regeneration genes (fgf20a, msxb, sox9b) whose expression was associated with dynamic methylation changes in their promoters or gene bodies. We conclude that DNA methylation is a dynamic and key regulatory layer that acts in concert with transcriptional reprogramming to coordinate tissue regeneration, providing new insights into the epigenetic mechanisms underlying complex regenerative processes in teleosts.

Animals

Transcriptomic Profiling Reveals NF-κB-Associated Immune Regulatory Signatures Underlying the Regenerative Effects of Hypoxia-Preconditioned Tendon Stem Cell-Derived Extracellular Vesicles.

Remodeling of the immune microenvironment is a critical determinant of tissue regeneration, yet the molecular programs associated with the enhanced therapeutic activity of hypoxia-preconditioned extracellular vesicles remain incompletely defined. In this study, we investigated the regenerative and immunomodulatory effects of hypoxia-preconditioned tendon stem cell-derived extracellular vesicles (Hypo-EVs) and employed transcriptomic profiling to identify molecular signatures associated with their biological activity. The therapeutic effects of Hypo-EVs were evaluated using a rat patellar tendon defect model and lipopolysaccharide-stimulated RAW 264.7 macrophages. Histological analysis, immunostaining, biomechanical testing, and reverse transcription-quantitative polymerase chain reaction were performed to assess tendon healing and macrophage polarization, while RNA sequencing was conducted in macrophages treated with Hypo-EVs or normoxia-derived EVs, followed by Gene Set Enrichment Analysis, Gene Ontology, and Kyoto Encyclopaedia of Genes and Genomes pathway analyses. Hypo-EVs significantly alleviated local inflammatory responses, improved collagen organization and biomechanical properties of repaired tendons, and promoted macrophage polarization toward a reparative M2 phenotype both in vivo and in vitro. Consistent with these biological effects, transcriptomic profiling revealed extensive remodeling of inflammation-related gene expression programs, including significant suppression of NF-κB, TNF, IL-17, and cytokine-cytokine receptor interaction pathways. Integrative bioinformatic analyses identified an NF-κB-associated immune-regulatory signature that distinguished Hypo-EV-treated macrophages from those receiving normoxic EVs. Mechanistically, Hypo-EVs attenuated NF-κB activation, as evidenced by reduced phosphorylation of p65 and IκBα, whereas TNF-α-mediated NF-κB activation partially diminished their macrophage-repolarizing effects. Collectively, these findings demonstrate that hypoxic preconditioning enhances the immunomodulatory and regenerative functions of tendon stem cell-derived EVs. Transcriptomic analyses identified an NF-κB-associated immune-regulatory signature linked to the biological activity of Hypo-EVs, providing a molecular framework for understanding EV-mediated immune modulation and supporting the development of transcriptome-guided molecular signatures for regenerative therapies targeting tendon immune homeostasis.

Animals

The requirement for DNA synthesis and gene expression in the generation of cytotoxicity in vitro.

The requirement for cell division and expression of new genes was examined in the primary and secondary mouse mixed leukocyte culture (MLC). Hydroxyurea (HU) was used to block DNA synthesis and cell division, and 5-bromo-2'-deoxyuridine (BUdR) was used to probe for the expression of new cell-specific genes. In the primary MLC, inhibition of DNA synthesis and cell division by HU almost totally suppressed the generation of initial, target-specific cytotoxicity. When HU was washed out of the cultures, cytotoxicity was generated after a lag time approximately equal to the period of treatment with HU. The rate of development and maximal value of cytotoxicity in HU-reversed cultures was identical to untreated controls, suggesting that the inhibition was not due to a nonspecific lethal effect of the drug. Development of initial cytotoxicity in primary MLC was similarly suppressed by levels of BUdR 25 to 75-fold below the levels of this drug having nonspecific mutagenic effects in lymphocytes, indicating that development of cytotoxicity was also dependent on the expression of a new genetic program. In the secondary MLC, regeneration of both DNA synthesis and cytotoxicity was apparent 12-15 h after re-exposure to initial stimulating antigen. In this reaction, however, generation of cytotoxicity was insensitive to both HU and BUdR. Thus, the cytotoxic program developed in the primary MLC appears to be genetically stable through the production of effector memory cells, and into regeneration of fully cytotoxic memory cells in secondary MLC.

Animals

BACH1 orchestrates macrophage state transitions to coordinate regenerative inflammation.

Efficient tissue regeneration requires the precise coordination of inflammatory and regenerative programs, principally mediated by monocyte-derived macrophages. However, the transcriptional wiring and epigenomic processes behind complex macrophage subtype specification and transition between the different states are not known. Here we have identified the transcriptional repressor BACH1 as a critical, cell-intrinsic regulator of monocyte-derived macrophage specification during skeletal muscle regeneration. Using a myeloid-specific BACH1 knockout mouse model, we demonstrate that BACH1 deficiency disrupts the temporal coordination of monocyte-to-macrophage differentiation, leading to aberrant macrophage subsets with concurrent opposing pro- and anti-inflammatory features. Single-cell RNA-sequencing profiling reveals that BACH1 controls a core transcriptional network, including Nfkb1, Cebpb, and interferon signaling, governing inflammatory resolution and functional macrophage specialization. Mechanistically, BACH1 loss accelerates macrophage differentiation but also affects its core cellular identity, resulting in sustained, rather than declining inflammatory programs including upregulation of Il1b and thus, defective tissue remodeling. These immune alterations compromise the paracrine landscape during regenerative inflammation and impair muscle stem cell differentiation. Our findings establish BACH1 as a molecular tuner or controller that integrates early innate immune signaling with regenerative output, positioning it as a central node linking transcriptional control, immune fate decisions, and tissue repair.

Animals

The role of transposable elements-endogenous retroviruses in embryonic development and regeneration.

Endogenous retroviruses (ERVs) are dynamically regulated across the lifespan and can function as context-dependent components of host gene-regulatory networks. During embryonic development, selected ERV-derived elements are co-opted to support zygotic genome activation, lineage specification, and placental development. In adult tissues, ERV-derived sequences can contribute to tissue and immune homeostasis, whereas potentially disruptive ERV activity is constrained by epigenetic mechanisms. During regeneration and somatic cell reprogramming, ERV and broader transposable-element programs undergo transient, locus-specific remodeling. In aging, the weakening of epigenetic and nuclear restraint can promote aberrant ERV derepression, inflammation, and functional decline. This review summarizes the diverse roles of ERVs across these contexts and discusses the challenges of defining locus-specific functions, resolving repetitive sequences, and developing safe ERV-targeted interventions.

Endogenous Retroviruses

Macrophage plasticity and metabolic control in muscle repair and disease.

Inflammation is a tightly regulated process essential for skeletal muscle repair, and its dysregulation contributes to chronic disease and impaired regeneration. Following injury, muscle repair involves a coordinated immune response initiated by neutrophil infiltration, followed by macrophage recruitment and diversification. Rather than existing as discrete subsets, macrophages span a continuum of functional states that evolve over time in response to local environmental cues, enabling transitions from clearing debris and pro-inflammatory signaling to supporting resolution of inflammation, and remodeling and regeneration of the tissue. This functional plasticity is closely linked to intracellular metabolic programs. In this review, we examine how metabolic pathways, particularly the balance between glycolysis and oxidative phosphorylation, govern macrophage behavior through epigenetic mechanisms, thereby coupling cellular metabolism to inflammatory and regenerative gene expression. We further explore how these interconnected pathways are disrupted in chronic inflammatory muscle diseases, including muscular dystrophies. Recent transcriptomic studies highlight pathogenic macrophage populations with altered metabolic and epigenetic profiles that contribute to fibrosis and impaired regeneration. By integrating findings from both acute injury and chronic disease contexts, we provide a framework to explore macrophage function through a metabolic and epigenetic lens and discuss emerging strategies aimed at restoring macrophage plasticity and promoting the resolution of inflammation in muscle disease.

Humans

Light-activated CRISPR/dCas9 nanomedicine for programmable control of renal fibrosis.

Renal fibrosis is the final common pathway of progressive chronic kidney disease and is maintained by spatially heterogeneous interactions among injured epithelial cells, activated fibroblasts, immune cells, extracellular matrix remodeling, metabolic stress, and persistent profibrotic transcriptional programs. Current therapies slow renal functional decline but do not directly control the regulatory circuits that stabilize maladaptive repair. Photoresponsive renal nanomedicine offers a potential strategy to add external control to anti-fibrotic intervention by combining kidney-directed delivery with light-gated release or activation of molecular payloads. This review examines the emerging interface between photoresponsive nanomaterials and CRISPR/dCas9-based gene regulation for renal fibrosis, with emphasis on upconversion nanoparticles, photoresponsive polymers, ROS- and pH-responsive matrices, optogenetic switches, and renal-compartment-directed carrier design. We argue that the most defensible therapeutic objective is not permanent genome editing or autonomous organ regeneration, but spatially confined, temporally limited, and reversible regulation of validated fibrotic or protective gene programs using CRISPRa, CRISPRi, or dCas9-based epigenome editors. The review therefore evaluates material requirements, optical-dosimetry constraints, payload architecture, renal biodistribution, target-selection logic, safety risks, and preclinical validation criteria. By defining the engineering and biological conditions required for controlled anti-fibrotic regulation, this framework positions photoresponsive renal nanomedicine as a translationally testable route toward localized modulation of fibrotic cell states rather than an overextended claim of kidney regeneration.

Anti-fibrotic gene regulation

Molecular mechanisms of natural de novo shoot organogenesis and their applications.

Natural de novo shoot organogenesis (DNSO) is the spontaneous regeneration of shoots from wound sites outside the shoot apical region through endogenous developmental programs. This regenerative capacity enables plants to recover from severe tissue damage by re-establishing the shoot-root axis. Here, we review current knowledge about the molecular mechanisms of natural DNSO, focusing on transcriptomic and physiological studies in model plants. Accumulating evidence suggests that natural DNSO proceeds through three sequential phases: (i) early wound responses, characterized by the activation of the WIND1-ESR1 module and the establishment of apical-basal auxin asymmetry; (ii) cellular proliferation driven by metabolic and cell-cycle reprogramming; and (iii) cytokinin-mediated establishment of shoot apical meristem identity. We also discuss how these mechanistic insights have been harnessed for practical applications, including tissue culture-free transformation systems such as the cut-dip-budding (CDB) method, and developmental reprogramming strategies that employ ectopic expression of developmental regulator (DR) genes to induce DNSO in otherwise recalcitrant species. Together, these advances illustrate how understanding natural regeneration can guide the development of simplified, broadly applicable plant transformation technologies.

Plant Shoots

The L27 domain of MPP7 enhances TAZ-YY1 cooperation to renew muscle stem cells.

Stem cells regenerate differentiated cells to maintain and repair tissues and organs. They also replenish themselves, i.e. self-renew, to support a lifetime of regenerative capacity. Here we study the renewal of skeletal muscle stem cell (MuSC) during regeneration. The transcriptional co-factors TAZ/YAP (via the TEAD transcription factors) regulate cell cycle and growth while the transcription factor YY1 regulates metabolic programs for MuSC activation. We show that MPP7 and AMOT join TAZ and YY1 to regulate a selected number of common genes that harbor TEAD and YY1 binding sites. Among these common genes, Carm1 can direct MuSC renewal. We demonstrate that the L27 domain of MPP7 enhances the interaction as well as the transcriptional activity of TAZ and YY1, while AMOT acts as an intermediate to bridge them together. Furthermore, MPP7, TAZ and YY1 co-occupy the promoters of Carm1 and other common downstream genes. Our results define a renewal program comprised of two progenitor transcriptional programs, in which selected key genes are regulated by protein-protein interactions, dependent on promoter context.

YY1 Transcription Factor

Transcription regulation of cell fate plasticity - from embryonic development to tissue regeneration.

Cell fate plasticity refers to the capacity of cells sharing the same genome to alter, reverse, or reconfigure their identity under physiological, pathological, or experimental conditions. This property underlies embryonic development, cellular reprogramming, and tissue regeneration, but becomes progressively restricted as lineage identity is stabilized. Embryonic development represents an intrinsic process of fate transitions, whereas reprogramming and regeneration reveal how differentiated cells can dedifferentiate or transdifferentiate under specific conditions. Across these contexts, plasticity is governed by multilayered regulatory networks involving transcription factors, epigenetic regulators, cofactors, and the core transcription machinery. Robust regulatory programs stabilize cell identity, whereas stochastic fluctuations in gene expression and chromatin state can prime cells for fate transitions, adding a tunable dimension to plasticity control. In this review, we synthesize recent advances in the regulation of cell fate plasticity across development, reprogramming, and regeneration, highlighting how transcription factors, epigenetic modifications, transcriptional cofactors, and core transcription machinery cooperate to control cell fate decisions and plasticity.

Animals

Multi-omics technologies: Novel tools and methods for assessing nerve injury and regeneration.

Recently, with the rapid advancement of multi-omics technologies, including genomics, transcriptomics, proteomics, and metabolomics, new tools and approaches have been introduced for studying nerve injury and regeneration. This review highlights the application and progress of multi-omics in uncovering the mechanisms of nerve injury, guiding the development of regenerative strategies, and promoting clinical translation. By integrating multi-omics datasets, researchers can comprehensively track dynamic molecular changes following nerve injury, including abnormal gene expression, disrupted protein signaling, altered metabolic programs, and shifts in the immune microenvironment. Single-cell multi-omics technologies resolve cellular heterogeneity, revealing the distinct functions of neurons, glial cells, and immune cell subpopulations during the injury response. Spatially resolved transcriptomics maintain the spatial context of lesion and regeneration sites, enabling precise localization for targeted interventions. Multi-omics technologies not only identify key molecular players involved in nerve regeneration but also create opportunities for personalized medicine. Nonetheless, integrating multi-omics data poses technical challenges, including high dimensionality, batch effects, and algorithmic constraints, while ethical concerns related to stem cell therapy and gene editing require stringent oversight. To transition from structural reconstruction to functional remodeling, future research should emphasize artificial intelligence-driven data integration, organ-on-a-chip modeling, and cross-disciplinary collaboration to overcome existing technical barriers and accelerate the clinical application of neuroregenerative therapies.

artificial intelligence

Epithelial regeneration in the gastrointestinal tract.

The gastrointestinal tract possesses a remarkable regenerative capacity to maintain tissue homeostasis against various injuries. However, the intestine and stomach exhibit distinct regenerative strategies. In the intestine, damage to Lgr5-positive (Lgr5+) stem cells induces cellular plasticity and the emergence of transient Revival stem cells (RevSCs), a process critically dependent on YAP/TAZ signaling. Conversely, the stomach utilizes paligenosis, where quiescent p57-positive (p57+) mature chief cells act as reserve stem cells, dedifferentiating to restore damaged tissue. Although the cellular origins differ, both organs appear to share some common regenerative features, including transient activation of pro-proliferative programs such as YAP/TAZ signaling. In contrast, whether Retinoic Acid (RA) signaling also serves as a conserved mechanism for regenerative resolution in the stomach remains to be determined. In this review, we discuss the cellular and molecular mechanisms governing regeneration in these two organs. This comparative analysis provides a framework for future research.

Regeneration

Review: The African turquoise killifish as a model for the integrative physiology of vertebrate aging.

With increasing emphasis on extending healthy lifespan, aging research requires vertebrate models that permit efficient mechanistic investigation and intervention testing within practical time and cost constraints. The African turquoise killifish (Nothobranchius furzeri) has attracted growing attention because it combines an exceptionally short life cycle with an intact vertebrate physiological context and an expanding genetic toolkit, enabling relatively rapid evaluation of candidate aging interventions and mechanistic analysis across molecular, tissue, and organismal levels. This review assesses N. furzeri from an integrative-physiology perspective, focusing on germline-soma interactions, gut microbiota-host crosstalk, nutrient sensing and metabolic remodeling, temperature responsiveness, and AMPK-mTOR-linked programs. It also examines expanding genome-engineering and reporter approaches that support mechanistic and tissue-resolved investigation of these physiological processes. Building on recent reviews of killifish biology, disease modeling, regeneration, and the hallmarks of aging, we synthesize evidence across major intervention domains, distinguish established phenotypic effects from incompletely resolved mechanisms, and highlight functional endpoints, methodological standardization, and the appropriate interpretation of the model's translational relevance. Together, these features position N. furzeri as a strategically useful vertebrate platform for rapid mechanistic testing, intervention evaluation, and prioritization of aging-related pathways. Future progress will require improved methodological standardization, tissue-resolved causal studies, and question-driven cross-species validation where appropriate.

Animals

Deep learning-assisted, pathogenesis-informed lung histopathology scoring in preclinical mouse models of SARS-CoV-2 and influenza A infection.

INTRODUCTION: SARS-CoV-2 and influenza A virus (IAV) cause viral pneumonia, yet their lung lesions evolve with distinct spatial organization and resolution-phase architecture. In preclinical murine studies, H&E histopathology is a primary endpoint, but burden-focused semiquantitative scoring can miss pathogen- and phase-specific differences in lesion topology, compartmental involvement, inflammatory organization, and repair. We aimed to define virus- and phase-specific morphologic signatures and translate them into a practical, pathogenesis-informed scoring guide, supported by whole-slide convolutional neural network (CNN) analysis with class activation mapping (CAM). METHODS: Mice were infected under standardized conditions and evaluated during the early, peak-injury, and late phases of infection, corresponding to 2~3, 5~8, and 14 days post-infection (dpi), respectively. Lungs were assessed by H&E with semiquantitative scoring and by immunostaining to map viral antigen distribution and epithelial tropism. Whole-slide CNN models were trained for virus- and phase-specific classification, and CAM localized discriminative regions. RESULTS: Dose titration established reproducible lethal and sublethal infection conditions for both viruses. Viral antigen kinetics diverged, with SARS-CoV-2 peaking early and declining toward clearance by the resolution phase, whereas IAV peaked later and declined by the resolution phase, paralleling distinct injury-repair trajectories. CNN/CAM analysis distinguished virus- and phase-specific histologic patterns across the early, peak-injury, and resolution phases of infection and highlighted spatial signatures consistent with expert review. At the peak-injury phase, SARS-CoV-2 lungs showed broad alveolar/interstitial involvement, whereas IAV exhibited bronchocentric inflammatory organization. During the resolution phase, IAV showed prominent epithelial regeneration with remodeling-forward architecture, while SARS-CoV-2 more often retained localized residual inflammatory foci. Across both infections, tissue inflammatory composition shifted over time, with higher neutrophil representation during the peak-injury phase and a relative increase in lymphocytic representation during the resolution phase. Integrating lesion topology/distribution, edema, epithelial injury-regeneration, remodeling features, and lymphocyte predominance, we proposed a pathogen-resolved, phase-informed histopathology scoring guide with recommended evaluation windows for each model. CONCLUSION: Together, these findings define virus- and phase-specific morphologic programs that inform respiratory virus pathogenesis in mice and can be translated into practical scoring criteria for preclinical respiratory virus studies.

Animals

Fetal-like reversion in the regenerating intestine is regulated by mesenchymal asporin.

Mesenchymal cells and the extracellular matrix (ECM) support epithelium during homeostasis and regeneration. However, the role of the mesenchyme in epithelial conversion into a fetal-like regenerative state after damage is not known. We modeled epithelial regeneration by culturing intestinal epithelium on decellularized small intestinal scaffolds (iECM) and identify asporin (Aspn), an ECM-bound proteoglycan, as a critical mediator of epithelial fetal-like reprogramming. After damage, transient increase in Aspn expression by the pericryptal fibroblasts induces epithelial transforming growth factor β (TGF-β)-signaling via CD44 and promotes timely epithelial reprogramming. Temporal control of Aspn is lost in old mice, and after damage, the persistently high level of Aspn stagnates epithelium in the regenerative state. Increase in Wnt signaling can resolve the stagnated regenerative program of the old epithelium, promoting restoration of tissue function. In summary, we establish a platform for modeling epithelial injury responses ex vivo and show that the mesenchymal Aspn-producing niche modulates tissue repair by regulating epithelial fetal-like reprogramming.

Animals

[Theories and models of the biology of aging].

Two main theories of aging were discussed: program theory, error theory. The importance of repair mechanisms is disclosed. 4 models (Lag-phase, proliferative capacity, physical properties of collagen, latency period) display typical phenomenons of the biology of aging.

Aging

Hypoxia-inducible factor 2 regulates alveolar regeneration after repetitive injury in three-dimensional cellular and in vivo models.

Idiopathic pulmonary fibrosis (IPF) is a progressive interstitial lung disease in which repetitive epithelial injury and incomplete alveolar repair result in accumulation of profibrotic intermediate/transitional "aberrant" epithelial cell states. The mechanisms leading to the emergence and persistence of aberrant epithelial populations in the distal lung remain incompletely understood. By interrogating single-cell RNA sequencing (scRNA-seq) data from patients with IPF and a mouse model of repeated lung epithelial injury, we identified persistent activation of hypoxia-inducible factor (HIF) signaling in these aberrant epithelial cells. Using mouse genetic lineage-tracing strategies together with scRNA-seq, we found that these disease-emergent aberrant epithelial cells predominantly arose from airway-derived (Scgb1a1-CreER-traced) progenitors and exhibited transcriptional programs of Hif2a activation. In mice treated with repetitive intratracheal bleomycin, deletion of Epas1 (Hif2a) but not Hif1a, from airway-derived progenitors, or administration of the small-molecule HIF2 inhibitor PT-2385, using both prevention and rescue approaches, attenuated experimental lung fibrosis, reduced the appearance of aberrant epithelial cells, and promoted alveolar repair. In mouse alveolar organoids, genetic or pharmacologic inhibition of Hif2 promoted alveolar differentiation of airway-derived epithelial progenitors. In addition, treatment of human distal lung organoids with PT-2385 increased colony-forming efficiency, enhanced protein and transcriptional markers of alveolar type 2 epithelial cell maturation, and prevented the emergence of aberrant epithelial cells. Together, these studies showed that HIF2 activation drives the emergence of aberrant epithelial populations after repetitive injury and that targeted HIF2 inhibition may represent an effective therapeutic strategy to promote functional alveolar repair in IPF and other interstitial lung diseases.

Animals