BACH1 changes microglial metabolism and affects astrogenesis during mouse brain development

Metabolic reprogramming of astrocytes: Emerging roles of lactate

Lactate serves as a key energy metabolite in the central nervous system, facilitating essential brain functions, including energy supply, signaling, and epigenetic modulation. Moreover, it links epigenetic modifications with metabolic reprogramming. Nonetheless, the specific mechanisms and roles of this connection in astrocytes remain unclear. Therefore, this review aims to explore the role and specific mechanisms of lactate in the metabolic reprogramming of astrocytes in the central nervous system. The close relationship between epigenetic modifications and metabolic reprogramming was discussed. Therapeutic strategies for targeting metabolic reprogramming in astrocytes in the central nervous system were also outlined to guide future research in central nervous system diseases. In the nervous system, lactate plays an essential role. However, its mechanism of action as a bridge between metabolic reprogramming and epigenetic modifications in the nervous system requires future investigation. The involvement of lactate in epigenetic modifications is currently a hot research topic, especially in lactylation modification, a key determinant in this process. Lactate also indirectly regulates various epigenetic modifications, such as N6-methyladenosine, acetylation, ubiquitination, and phosphorylation modifications, which are closely linked to several neurological disorders. In addition, exploring the clinical applications and potential therapeutic strategies of lactic acid provides new insights for future neurological disease treatments.

Glycolytic dysregulation in Alzheimer's disease: unveiling new avenues for understanding pathogenesis and improving therapy

Alzheimer's disease poses a significant global health challenge owing to the progressive cognitive decline of patients and absence of curative treatments. The current therapeutic strategies, primarily based on cholinesterase inhibitors and N-methyl-D-aspartate receptor antagonists, offer limited symptomatic relief without halting disease progression, highlighting an urgent need for novel research directions that address the key mechanisms underlying Alzheimer's disease. Recent studies have provided insights into the critical role of glycolysis, a fundamental energy metabolism pathway in the brain, in the pathogenesis of Alzheimer's disease. Alterations in glycolytic processes within neurons and glial cells, including microglia, astrocytes, and oligodendrocytes, have been identified as significant contributors to the pathological landscape of Alzheimer's disease. Glycolytic changes impact neuronal health and function, thus offering promising targets for therapeutic intervention. The purpose of this review is to consolidate current knowledge on the modifications in glycolysis associated with Alzheimer's disease and explore the mechanisms by which these abnormalities contribute to disease onset and progression. Comprehensive focus on the pathways through which glycolytic dysfunction influences Alzheimer's disease pathology should provide insights into potential therapeutic targets and strategies that pave the way for groundbreaking treatments, emphasizing the importance of understanding metabolic processes in the quest for clarification and management of Alzheimer's disease.

Gastrodin alleviates Aβ25-35-induced glycolytic dysfunction via activating PI3K/AKT/BACH1 signaling in Alzheimer's disease models

Cerebral glycolytic alteration has been identified as an important contributor to the pathological progress of Alzheimer's disease (AD). Research has shown that gastrodin (GAS) possesses neuroprotection in various experimental models of AD, but its specific mechanism remains unclear. In this study, we determined whether GAS exerted neuroprotective effects on AD models through regulating PI3K/AKT/BACH1 signaling axis. Eight-week-old C57BL/6 J male mice were intracerebroventricularly injected with Aβ25-35, to establish an AD model, followed by the administration of GAS (30, 60 mg·kg-1·d-1, i.g.) for 21 days. Treatment of GAS markedly alleviated the downregulation of p-PI3K Tyr199/458, p-AKT Ser473, BACH1 and HK1 in the hippocampus of the Aβ25-35-induced AD mice. To further explore the mechanism of GAS-mediated neuroprotection, an in vitro AD cellular model was established by challenging HT22 cells with Aβ25-35. In the Aβ25-35 induced cells, the expression of BACH1, p-PI3K Tyr199/458 and p-AKT Ser473 was reduced, the mRNA and protein levels of HK1 were decreased, and the levels of pyruvate and ATP were reduced. After treatment of GAS, the decline of these indicators was reversed. In addition, overexpression of BACH1 by lentivirus transfection significantly upregulated the mRNA and protein levels of HK1, thereby enhancing glycolytic function and protecting HT22 cells from Aβ25-35-induced injury. The results of chromatin immunoprecipitation assay-real-time quantitative PCR revealed that BACH1 directly bound to the HK1 promoter region. Collectively, these findings suggest that GAS can play a protective role in Aβ25-35-induced experimental AD models by increasing HK1 expression and ameliorating glycolytic dysfunction through activation of the PI3K/AKT/BACH1 signaling axis.

Unraveling Neurodevelopment: Synergistic Effects of Intrinsic Genetic Programs and Extrinsic Environmental Cues

The development of the brain involves the proliferation of neural stem cells (NSCs) and the differentiation of neurogenic cells, including neurons, astrocytes, and oligodendrocytes. The growth and development of other cells in the brain, including microglia and blood vessels, are also crucial for maintaining normal brain function. In the first part, the intrinsic regulatory mechanisms of NSCs during neurogenesis are primarily delved into. This focused on the effects of epigenetic modifications on the proliferation and differentiation of NSCs. Additionally, the phenomenon where their own proliferative behavior leads to the activation of immune-related genes are discussed. Furthermore, the impact of maternal immune activation on neurogenesis are explored. Finally, the reasons underlying differences in brain development between humans and mice are examined. In the second part, the development and origin of microglia, their heterogeneity during the developmental process, and the impact of microglia on the development of surrounding cells are delved into. In the third part, the relationship between the cerebrovascular system and brain development are explored. This includes the communication and interaction between blood vessels and NSCs, as well as the effects of cytokines secreted by blood vessels on synapses and the genesis of glial cells.

The regulatory role of protein lactylation in various diseases: Special focus on the regulatory role of non-histone lactylation

Lactylation, an emerging form of post-translational modification derived from lactate, plays a pivotal role in numerous cellular processes such as tumor proliferation, metabolism, inflammation, and embryonic development. However, the precise molecular mechanisms by which lactylation controls these biological functions in both physiological and pathological contexts remain elusive. This review summarizes the latest reported regulatory mechanisms of protein lactylation in various diseases since 2024, introducing the latest research progress regarding the regulatory functions of protein lactylation in pathological processes, with particular attention to the regulatory mechanisms of non-histone lactylation modification in diseases. Finally, it outlines the potential of targeted lactylation therapy, proposes the main directions for future research, and emphasizes its scientific significance for future studies.

Lactylation and Ischemic Stroke: Research Progress and Potential Relationship

Ischemic stroke is caused by interrupted cerebral blood flow and is a leading cause of mortality and disability worldwide. Significant advancements have been achieved in comprehending the pathophysiology of stroke and the fundamental mechanisms responsible for ischemic damage. Lactylation, as a newly discovered post-translational modification, has been reported to participate in several physiological and pathological processes. However, research on lactylation and ischemic stroke is scarce. This review summarized the current function of protein lactylation in other diseases or normal physiological processes and explored their potential link with the pathophysiological process and the reparative mechanism of ischemic stroke. We proposed that neuroinflammation, regulation of metabolism, regulation of messenger RNA translation, angiogenesis, and neurogenesis might be the bridge linking lactylation and ischemic stroke. Our study provided a novel perspective for comprehending the role of protein lactylation in the pathophysiological processes underlying ischemic stroke. Lactylation might be a promising target in drug development of ischemic stroke.

Physical Exercise Decreases Complement-Mediated Synaptic Loss and Protects Against Cognitive Impairment by Inhibiting Microglial Tmem9-ATP6V0D1 in Alzheimer's Disease

Physical exercise is known to slow synaptic neurodegeneration and cognitive aging in Alzheimer's disease (AD). The benefits of physical exercise are related to reduced amyloid beta (Aβ) deposition and increased synaptic plasticity. Yet little is known about the mechanisms that mediate these effects. Here, we show that physical exercise down-regulated the microglial Tmem9 protein, inhibited C1q activation, and decreased C1q-dependent microglial synapse engulfment, eventually ameliorating cognitive impairment in 5xFAD mice. Furthermore, using oAβ cultured-BV2 in vitro, we show that downregulation of microglial Tmem9 was sufficient to restrain complement activity and decrease microglia-mediated synaptic loss, whereas overexpression of microglial Tmem9 tended to promote complement activation and induced synaptic loss, abolishing exercise-associated protection. Finally, we show that microglial Tmem9 contributed to complement activation by regulating ATP6V0D1, a vesicular (H+) ATP-dependent proton pump (V-ATPase) subunit that regulates V-ATPase assembly. Together, our results demonstrate that exercise is a potential treatment for AD patients. In an AD mouse model, it decreased the levels of microglial Tmem9 to inhibit the activation of complement, alleviated complement-dependent synaptic loss, and eventually ameliorated emotional and cognitive disorders.

The role of protein lactylation in brain health and disease: current advances and future directions

Lactate, the end product of glycolysis, plays a crucial role in cellular signaling and metabolism. The discovery of lactylation, a novel post-translational modification, has uncovered the role of lactate in regulating diseases, especially in the brain. Lactylation connects genetic encoding with protein function, thereby influencing key biological processes. Increasing evidence supports lactate-mediated lactylation as a critical modulator in neurological disorders. This review offers an overview of lactate metabolism and lactylation, highlighting recent advances in understanding the regulatory enzymes of lactylation and their role in the central nervous system. We investigate the impact of lactylation on brain dysfunctions, including neurodegenerative diseases, cerebrovascular disorders, neuroinflammation, brain tumors, and psychiatric conditions. Moreover, we highlight the therapeutic potential of targeting lactylation in treating brain disorders and outline key research gaps and future directions needed to advance this promising field.

Semaphorin 6A phase separation sustains a histone lactylation-dependent lactate buildup in pathological angiogenesis

Ischemic retinal diseases are major causes of blindness worldwide and are characterized by pathological angiogenesis. Epigenetic alterations in response to metabolic shifts in endothelial cells (ECs) suffice to underlie excessive angiogenesis. Lactate accumulation and its subsequent histone lactylation in ECs contribute to vascular disorders. However, the regulatory mechanism of establishing and sustaining lactylation modification remains elusive. Here, we showed that lactate accumulation induced histone lactylations on H3K9 and H3K18 in neovascular ECs in the proliferative stage of oxygen-induced retinopathy. Joint CUT&Tag and scRNA-seq analyses identified Prmt5 as a target of H3K9la and H3K18la in isolated retinal ECs. EC-specific deletion of Prmt5 since the early stage of revascularization suppressed a positive feedback loop of lactate production and histone lactylation, thus inhibiting neovascular tuft formation. Mechanistically, the C-terminal intrinsically disorder region (IDR) of the transmembrane semaphorin 6A (SEMA6A) forms liquid-liquid phase separation condensates to recruit RHOA and P300, facilitating P300 phosphorylation and histone lactylation cycle. Deletion of endothelial Sema6A reduced H3K9la and H3K18la at the promoter of PRMT5 and diminished its expression. The induction of histone lactylation by SEMA6A-IDR and its pro-angiogenic effect were abrogated by deletion of Prmt5. Our study illustrates a sustainable histone lactylation machinery driven by phase separation-dependent lactyltransferase activation in dysregulated vascularization.

Lactylation in CNS disorders: mechanisms, cellular function, and disease relevance

Lactate, as a metabolic product or energy substrate, participates in various neurological processes within the physiological and pathological frameworks of the central nervous system (CNS). The groundbreaking application of multi-omics integration technologies has unveiled a novel role for lactate: lactylation, a unique post-translational modification (PTM) that covalently attaches lactate groups to lysine residues on proteins. This process precisely regulates protein function and gene expression, profoundly influencing the progression of various diseases. The lactylation process is meticulously regulated by a variety of key enzymes and metabolic pathways, forming a dynamic and intricate modification network. In this review, we summarize the key enzymes involved in lactylation, specifically "Writers," "Erasers," and "Readers." Furthermore, we systematically categorize lactylation observed in various cell types within the CNS and investigate its multifaceted roles in pathological processes, including neurodegenerative diseases, brain tumors, and brain injuries. By consolidating the latest research findings in this field, our review aims to highlight the significance of these discoveries for future research and explore their potential for translational applications.

Early central nervous system development and neuron regeneration

The nervous system is the most complex system in the human body, and the normal development of the central nervous system (CNS) is essential for maintaining the healthy life activities of the individual. CNS development requires the orchestration of multiple internal or external or direct or indirect factors to regulate neural stem cell fate specification. Here, we provide a broad overview of the regulatory system of nerve cell fate decisions and discuss the latest technological approaches to achieve neural regeneration. Understanding the CNS development and regeneration mechanisms has shifted the paradigm from traditional experiments to high-throughput sequencing.

Coptisine improves LPS-induced anxiety-like behaviors by regulating the Warburg effect in microglia via PKM2

Neuroinflammation mediated by microglia is considered the primary cause and pathological process of anxiety. Abnormal glycolysis of microglia is observed during microglia activation. However, whether regulating the Warburg effect in microglia can effectively intervene anxiety and its potential mechanisms have not been elucidated. This study focused on coptisine (Cop), a natural alkaloid that regulates the glycolysis and function of microglia affecting anxiety. The effects of Cop on anxiety-like behaviors, hippocampal synaptic function, and excessive activation of microglia were assessed in lipopolysaccharide (LPS) induced mouse models of anxiety. Microglia expressing mutant pyruvate kinase isoform M2 (PKM2) were used to further investigate the molecular mechanism by which Cop regulates the phenotype of microglia. neuroinflammatory is emerging Further research revealed that Cop attaches to the amino acid residue phenylalanine 26 of PKM2, shifting the dynamic equilibrium of PKM2 towards tetramers, and enhancing its pyruvate kinase activity. This interaction prevented LPS-induced Warburg effect and inactivated PKM2/hypoxia-inducible factor-1α (HIF-1α) pathway in microglia. In conclusion, Cop attenuates anxiety by regulating the Warburg effect in microglia. Our work revealed the role of PKM2/(HIF-1α) pathway in anxiety for the first time. Importantly, the molecular mechanism by which Cop ameliorates anxiety-like behaviors is through modulation of the dimeric/tetrameric form of PKM2, indicating the usefulness of PKM2 as a key potential target for the treatment of anxiety.

Insight into the roles of lactylation in macrophages: functions and clinical implications

Lactylation, a post-translational modification, has been linked to gene transcription regulation through epigenetic modulation in various pathophysiological processes. The lactylation regulatory proteins, known as writers, erasers, and readers, govern their dynamics by adding, removing, and recognizing lactyl groups on proteins. Macrophages, as cells of the immune system, maintain homeostasis, responding dynamically to diverse internal and external stimuli. Emerging researches unveil that lactylation, through inducing macrophage activation and polarization, affects their functionality in pathological conditions such as inflammation, tumor microenvironment, and fibrosis. Evidence progressively indicates that lactate-driven alterations in lactylation levels within macrophages can influence the pathogenesis of numerous diseases. This review aims to systematically summarize the research progress of lactylation in macrophages, explore its functions and mechanisms by which lactylation contributes to the pathology of different disease phenotypes, and propose future research directions along with potential diagnostic and therapeutic strategies.

Histone lactylation in macrophage biology and disease: from plasticity regulation to therapeutic implications

Epigenetic modifications have been identified as critical molecular determinants influencing macrophage plasticity and heterogeneity. Among these, histone lactylation is a recently discovered epigenetic modification. Research examining the effects of histone lactylation on macrophage activation and polarization has grown substantially in recent years. Evidence increasingly suggests that lactate-mediated changes in histone lactylation levels within macrophages can modulate gene transcription, thereby contributing to the pathogenesis of various diseases. This review provides a comprehensive analysis of the role of histone lactylation in macrophage activation, exploring its discovery, effects, and association with macrophage diversity and phenotypic variability. Moreover, it highlights the impact of alterations in macrophage histone lactylation in diverse pathological contexts, such as inflammation, tumorigenesis, neurological disorders, and other complex conditions, and demonstrates the therapeutic potential of drugs targeting these epigenetic modifications. This mechanistic understanding provides insights into the underlying disease mechanisms and opens new avenues for therapeutic intervention.

TFAP2A drives non-small cell lung cancer (NSCLC) progression and resistance to targeted therapy by facilitating the ESR2-mediated MAPK pathway

Cancer is among the leading causes of death related diseases worldwide, and lung cancer has the highest mortality rate in the world. Transcription factors (TFs) constitute a class of structurally and functionally intricate proteins. Aberrant expression or functional deficiencies of transcription factors may give rise to abnormal gene expression, contributing to various diseases, including tumours. In this study, we propose to elucidate the potential role and mechanism of TFAP2A in NSCLC. We found that TFAP2A levels were significantly greater in tumour tissues than para-tumour tissues, and high expression of TFAP2A was associated with poor prognosis in NSCLC patients. Additionally, TFAP2A overexpression promoted NSCLC progression both in vivo and in vitro. Mechanistically, ESR2 is a potential target regulated by TFAP2A and that TFAP2A can bind to the promoter region of ESR2. Furthermore, the overexpression of both TFAP2A and ESR2 in NSCLC cells was associated with the overactivation of MAPK signalling, and the combination of PHTPP and osimertinib had a synergistic effect on suppressing tumour growth.

Glycolytic reprogramming in microglia: A potential therapeutic target for ischemic stroke

Ischemic stroke is currently the second leading cause of mortality worldwide, with limited treatment options available. As resident immune cells, microglia promptly respond to cerebral ischemic injury, influencing neuroinflammatory damage and neurorepair. Studies suggest that microglia undergo metabolic reprogramming from mitochondrial oxidative phosphorylation to glycolysis in response to ischemia, significantly impacting their function during ischemic stroke. Therefore, this study aims to investigate the roles and regulatory mechanisms involved in this process, aiming to identify a new therapeutic target or potential drug candidate.

Lactate metabolism and histone lactylation in the central nervous system disorders: impacts and molecular mechanisms

Brain takes up approximately 20% of the total body oxygen and glucose consumption due to its relatively high energy demand. Glucose is one of the major sources to generate ATP, the process of which can be realized via glycolysis, oxidative phosphorylation, pentose phosphate pathways and others. Lactate serves as a hub molecule amid these metabolic pathways, as it may function as product of glycolysis, substrate of a variety of enzymes and signal molecule. Thus, the roles of lactate in central nervous system (CNS) diseases need to be comprehensively elucidated. Histone lactylation is a novel lactate-dependent epigenetic modification that plays an important role in immune regulation and maintaining homeostasis. However, there's still a lack of studies unveiling the functions of histone lactylation in the CNS. In this review, we first comprehensively reviewed the roles lactate plays in the CNS under both physiological and pathological conditions. Subsequently, we've further discussed the functions of histone lactylation in various neurological diseases. Furthermore, future perspectives regarding histone lactylation and its therapeutic potentials in stroke are also elucidated, which may possess potential clinical applications.

Lactylation: A Novel Post-Translational Modification with Clinical Implications in CNS Diseases

Lactate, an important metabolic product, provides energy to neural cells during energy depletion or high demand and acts as a signaling molecule in the central nervous system. Recent studies revealed that lactate-mediated protein lactylation regulates gene transcription and influences cell fate, metabolic processes, inflammation, and immune responses. This review comprehensively examines the regulatory roles and mechanisms of lactylation in neurodevelopment, neuropsychiatric disorders, brain tumors, and cerebrovascular diseases. This analysis indicates that lactylation has multifaceted effects on central nervous system function and pathology, particularly in hypoxia-induced brain damage. Highlighting its potential as a novel therapeutic target, lactylation may play a significant role in treating neurological diseases. By summarizing current findings, this review aims to provide insights and guide future research and clinical strategies for central nervous system disorders.

The pyruvate dehydrogenase complex at the epigenetic crossroads of acetylation and lactylation

The pyruvate dehydrogenase complex (PDC) is remarkable for its size and structure as well as for its physiological and pathological importance. Its canonical location is in the mitochondrial matrix, where it primes the tricarboxylic acid (TCA) cycle by decarboxylating glycolytically-derived pyruvate to acetyl-CoA. Less well appreciated is its role in helping to shape the epigenetic landscape, from early development throughout mammalian life by its ability to "moonlight" in the nucleus, with major repercussions for human healthspan and lifespan. The PDC's influence on two crucial modifiers of the epigenome, acetylation and lactylation, is the focus of this brief review.

Metabolic Control of Microglia

Microglia, immune sentinels of the central nervous system (CNS), play a critical role in maintaining its health and integrity. This chapter delves into the concept of immunometabolism, exploring how microglial metabolism shapes their diverse immune functions. It examines the impact of cell metabolism on microglia during various CNS states, including homeostasis, development, aging, and inflammation. Particularly in CNS inflammation, the chapter discusses how metabolic rewiring in microglia can initiate, resolve, or perpetuate inflammatory responses. The potential of targeting microglial metabolism as a therapeutic strategy for chronic CNS disorders with prominent innate immune cell activation is also explored.