Acetyl-CoA production by Mediator-bound 2-ketoacid dehydrogenases boosts de novo histone acetylation and is regulated by nitric oxide

Mechanisms of metabolism-coupled protein modifications

Intricate coupling between metabolism and protein post-translational modifications (PTMs) has emerged as a fundamental aspect of cellular regulation. Recent studies demonstrate that protein modifications can originate from diverse metabolites, and that their regulation is closely tied to the cellular metabolic state. Here we explore recently uncovered PTMs, including the concept of 'modification of a modification', as well as associated feedback and feedforward regulatory mechanisms, in which modified proteins impact not only related metabolic pathways but also other signaling cascades affecting physiology and diseases. The recently uncovered role of nucleus-localized metabolic enzymes for histone modifications additionally highlights the importance of cell-compartment-specific metabolic states. We further comment on the utility of untargeted metabolomics and proteomics for previously unrecognized PTMs and associated metabolic patterns. Together, these advances have uncovered a dynamic interplay between metabolism and PTMs, offering new perspectives for understanding metabolic regulation and developing targeted therapeutic strategies.

The effects of nitrite stress on metabolites and gene expression in sea Cucumbers (Apostichopus japonicus)

Chronic nitrite accumulation in intensive aquaculture poses a significant threat to the sustainability of sea cucumbers (Apostichopus japonicus), a key species in marine aquaculture. This study investigated the molecular and metabolic responses of A. japonicus to 21-day nitrite stress (4.88 mg/L) through transcriptomic and metabolomic analyses. At the end of the experiment, the weight gain rate of the Cg group was 11 %, while that of the Nc group was -9 %. Nitrite exposure significantly impaired growth performance of A. japonicus (p < 0.05). Metabolomic profiling identified 36 differential metabolites, revealing activation of the TCA cycle and amino acid metabolism to prioritize energy production and nitrogen reallocation. Transcriptomic data highlighted 226 differentially expressed genes. Notably, Zimp10, a key regulator of TCA cycle activity in echinoderms, was upregulated, while FALDH, a glycolysis-related gene, was downregulated, indicating a shift toward energy-efficient aerobic respiration. Antioxidant capacity was compromised through suppression of glutathione metabolism genes (MGST1, GST), exacerbating oxidative damage. Stress signaling pathways were dynamically regulated. Downregulation of Ras1-X2 suppressed mTOR activity, activating autophagy and mitophagy for cellular repair. Additionally, enrichment of NOD-like receptor pathways and upregulation of vGTPase1-like signaled immune engagement. Prolonged nitrite exposure overwhelmed adaptive mechanisms, leading to physiological decline. These results demonstrate A. japonicus of reliance on metabolic reprogramming and stress signaling to mitigate nitrite toxicity, while highlighting vulnerabilities in antioxidant defenses. The study provides critical insights for optimizing aquaculture environments through targeted management of nitrite exposure and metabolic resilience strategies.

A narrative review of epigenetic marker in H3K27ac and its emerging potential as a therapeutic target in cancer

Histone acetylation, particularly H3 K27 acetylation (H3K27ac), is a critical post-translational modification that regulates chromatin structure and gene expression, which plays a significant role in various cancers, including breast, colon, lung, hepatocellular, and prostate cancer. However, the mechanisms of H3K27ac in tumorigenesis are not yet comprehensive, especially its epigenetic mechanisms. This review endeavors to discuss findings on the involvement of H3K27ac in carcinogenesis within the past 5 years through a literature search using academic databases such as Web of Science. Firstly, we provide an overview of the diverse landscape of histone modifications, emphasizing the distinctive characteristics and critical significance of H3K27ac. Secondly, we summarize and compare advanced high-throughput sequencing technologies that have been utilized in the construction of the H3K27ac epigenetic map. Thirdly, we elucidate the role of H3K27ac in mediating gene transcription. Fourthly, we venture into the potential molecular mechanism of H3K27ac in cancer development. Finally, we engage in discussing future therapeutic approaches in oncology, with a spotlight on strategies that harness the potential of H3K27 modifications. In conclusion, this review comprehensively summarizes the characteristics of H3K27ac and underscores its pivotal role in cancer, providing valuable insights into its potential as a therapeutic target for cancer intervention.

Energy metabolism in health and diseases

Energy metabolism is indispensable for sustaining physiological functions in living organisms and assumes a pivotal role across physiological and pathological conditions. This review provides an extensive overview of advancements in energy metabolism research, elucidating critical pathways such as glycolysis, oxidative phosphorylation, fatty acid metabolism, and amino acid metabolism, along with their intricate regulatory mechanisms. The homeostatic balance of these processes is crucial; however, in pathological states such as neurodegenerative diseases, autoimmune disorders, and cancer, extensive metabolic reprogramming occurs, resulting in impaired glucose metabolism and mitochondrial dysfunction, which accelerate disease progression. Recent investigations into key regulatory pathways, including mechanistic target of rapamycin, sirtuins, and adenosine monophosphate-activated protein kinase, have considerably deepened our understanding of metabolic dysregulation and opened new avenues for therapeutic innovation. Emerging technologies, such as fluorescent probes, nano-biomaterials, and metabolomic analyses, promise substantial improvements in diagnostic precision. This review critically examines recent advancements and ongoing challenges in metabolism research, emphasizing its potential for precision diagnostics and personalized therapeutic interventions. Future studies should prioritize unraveling the regulatory mechanisms of energy metabolism and the dynamics of intercellular energy interactions. Integrating cutting-edge gene-editing technologies and multi-omics approaches, the development of multi-target pharmaceuticals in synergy with existing therapies such as immunotherapy and dietary interventions could enhance therapeutic efficacy. Personalized metabolic analysis is indispensable for crafting tailored treatment protocols, ultimately providing more accurate medical solutions for patients. This review aims to deepen the understanding and improve the application of energy metabolism to drive innovative diagnostic and therapeutic strategies.

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.