NAT10 regulates the LPS-induced inflammatory response via the NOX2-ROS-NF-κB pathway in macrophages

NAT10 mediated polycystic ovary syndrome through the ac4C modification of CXCL14

Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder among women of reproductive age, underscoring the critical importance of investigating its regulatory mechanisms. N-Acetyltransferase 10 (NAT10) is a crucial enzyme involved in mRNA acetylation modification, mediating target genes expression through N4-acetylcytidine (ac4C) modification to regulate the biological function of various diseases. Nonetheless, the specific role of NAT10 in PCOS regulation remains undisclosed. Ac4C dot hybridization experiment was conducted to determine ac4C expression in PCOS tissues. RT-qPCR was employed to assess the expression levels of NAT10 and CXCL14 in PCOS tissues and KGN cells. Cells viability was assessed using the CCK-8 method, while cell proliferation capacity was evaluated through the colony formation assay and EDU assay. Flow cytometry analysis was utilized to measure the apoptosis rate. The ac4C modification level was determined by acrp-qPCR analysis. RIP and luciferase reporter experiments confirmed the target binding relationship. The rat experiments confirmed the specific regulatory role of NAT10 in polycystic ovary syndrome in vivo. This study highlighted reduced levels of NAT10 and ac4C in PCOS, where silencing NAT10 boosts KGN cell proliferation and suppresses apoptosis. Additionally, NAT10-mediated ac4C modification governed the chemokine CXCL14 expression. Our research unveiled that NAT10 modulated PCOS occurrence and progression by enhancing the CXCL14 mRNA stability through acetylation, presenting potential novel insights into the mechanisms of mRNA acetylation in PCOS.

NAT10 promotes osteoclastogenesis in inflammatory bone loss by catalyzing Fos mRNA ac4C modification and upregulating MAPK signaling pathway

INTRODUCTION

Excessive osteoclastogenesis is a key driver of inflammatory bone loss. Suppressing osteoclastogenesis has always been considered essential for the treatment of inflammatory bone loss. N-acetyltransferase 10 (NAT10) is the sole enzyme responsible for N4-acetylcytidine (ac4C) modification of mRNA, and is involved in cell development. However, its role in osteoclastogenesis and inflammatory bone loss remained elusive.

OBJECTIVES

We aimed to clarify the regulatory mechanism of NAT10 and ac4C modification in osteoclastogenesis and inflammatory bone loss.

METHODS

NAT10 expression and ac4C modification during osteoclastogenesis were determined by quantitative real-time PCR (qPCR), western blotting, dot blot and immunofluorescent staining, and the effect of NAT10 inhibition on osteoclast differentiation in vitro was measured by the tartrate-resistant acid phosphatase staining, podosome belts staining assay and bone resorption pit assay. Then, acRIP-qPCR and NAT10RIP-qPCR, ac4C site prediction, mRNA decay assay and luciferase reporter assay were performed to further study the underlying mechanisms. At last, mice models of inflammatory bone loss were applied to verify the therapeutic effect of NAT10 inhibition in vivo.

RESULTS

NAT10 expression was upregulated during osteoclast differentiation and highly expressed in alveolar bone osteoclasts from periodontitis mice. Inhibition of NAT10 notably reduced osteoclast differentiation in vitro, as indicated by great reduction of tartrated resistant acid phosphatse positive multinuclear cells, osteoclast-specific gene expression, F-actin ring formation and bone resorption capacity. Mechanistically, NAT10 catalyzed ac4C modification of Fos (encoding AP-1 component c-Fos) mRNA and maintained its stabilization. Besides, NAT10 promoted MAPK signaling pathway and thereby activated AP-1 (c-Fos/c-Jun) transcription for osteoclastogenesis. Therapeutically, administration of Remodelin, the specific inhibitor of NAT10, remarkably impeded the ligature-induced alveolar bone loss and lipopolysaccharide-induced inflammatory calvarial osteolysis.

CONCLUSIONS

Our study demonstrated that NAT10-mediated ac4C modification is an important epigenetic regulation of osteoclast differentiation and proposed a promising therapeutic target for inflammatory bone loss.

NAT10 Regulates LPS-Induced Inflammation via Stabilization of N4-Acetylated PTX3 mRNA in Human Dental Pulp Stem Cells

Severe dental pulp inflammation can lead to tissue lysis and destruction, underscoring the necessity for effective treatment of pulpitis. N-acetyltransferase 10 (NAT10)-mediated N4-acetylcytidine (ac4C) modification has recently emerged as a key regulator in inflammatory processes. However, whether NAT10 affects the inflammatory response in human dental pulp stem cells (hDPSCs) remains unelucidated. In this study, elevated NAT10 expression was observed in pulpitis tissues and LPS-stimulated hDPSCs. Knockdown of NAT10 led to reduced inflammatory gene expression and lower reactive oxygen species (ROS) production in LPS-stimulated hDPSCs, while the chemotactic migration of macrophages was also suppressed. Similar results were observed when hDPSCs were treated with Remodelin, an inhibitor of NAT10. Differentially expressed genes identified through RNA sequencing were significantly enriched in inflammatory signaling pathways after NAT10 depletion. Among the differential genes, pentraxins 3 (PTX3) was identified as the potential target gene due to the presence of the ac4C modification site and its known ability to regulate dental pulp inflammation. The mRNA and protein levels of PTX3 were reduced in NAT10-deficient cells, along with a decrease in its mRNA stability. Exogenous PTX3 supplementation partially reversed the inflammatory inhibition induced by NAT10 knockdown. Further evidence in vivo revealed that Remodelin treatment attenuated the severity of dental pulp inflammation in rats with pulpitis. In summary, these data indicated that NAT10 deficiency inhibited the stability of PTX3 mRNA and further inhibited hDPSC inflammation, while Remodelin might be a potential therapeutic agent for pulp capping.

Nat10-mediated N4-acetylcytidine modification enhances Nfatc1 translation to exacerbate osteoclastogenesis in postmenopausal osteoporosis

Increased differentiation or activity of osteoclasts is the key pathogenic factor of postmenopausal osteoporosis (PMOP). N4-acetylcytidine (ac4C) modification, catalyzed by Nat10, is a novel posttranscriptional mRNA modification related to many diseases. However, its impact on regulating osteoclast activation in PMOP remains uncertain. Here, we initially observed that Nat10-mediated ac4C positively correlates with osteoclast differentiation of monocytes and low bone mass in PMOP. The specific knockout of Nat10 in monocytes and remodelin, a Nat10 inhibitor, alleviates ovariectomized (OVX)-induced bone loss by downregulating osteoclast differentiation. Mechanistically, epitranscriptomic analyses reveal that the nuclear factor of activated T cells cytoplasmic 1 (Nfatc1) is the key downstream target of ac4C modification during osteoclast differentiation. Subsequently, translatomic results demonstrate that Nat10-mediated ac4C enhances the translation efficiency (TE) of Nfatc1, thereby inducing Nfatc1 expression and consequent osteoclast maturation. Cumulatively, these findings reveal the promotive role of Nat10 in osteoclast differentiation and PMOP from a novel field of RNA modifications and suggest that Nat10 can be a target of epigenetic therapy for preventing bone loss in PMOP.

Tannic acid‑cerium nanoenzymes serve as broad-spectrum antioxidants to alleviate acute kidney injury by modulating macrophage polarization, mitophagy and endoplasmic reticulum stress

Acute kidney injury (AKI) is a critical condition marked by a rapid decline in renal function, primarily driven by oxidative stress, mitochondrial dysfunction, and inflammation. Despite extensive research, effective therapeutic strategies addressing the complex pathophysiology of AKI remain limited. In this study, we prepared a tannic acid‑cerium nanoenzyme (TA-Ce) and explored its potential for treating AKI. TA-Ce, synthesized via a one-pot method, demonstrated strong reactive oxygen species (ROS) scavenging, therapeutic efficacy, and biocompatibility in vitro and in vivo. TA-Ce, approximately 25.6 nm in size, was obtained by optimizing the molar ratios of TA to Ce and pH conditions, resulting in effective accumulation in the injured kidney. In addition, TA-Ce exhibited broad-spectrum antioxidant ability, capable of scavenging various ROS and alleviating oxidative stress. Notably, TA-Ce outperformed the conventional anti-inflammatory drug N-acetylcysteine (NAC) in both rhabdomyolysis-induced AKI (RM-AKI) and cisplatin-induced AKI (CP-AKI) mouse models. Mechanistic studies in RM-AKI revealed that TA-Ce disrupted the vicious cycle of oxidative stress, mitochondrial damage, endoplasmic reticulum stress, apoptosis, and inflammation. The nanoenzyme restored mitochondrial autophagic flux by inhibiting the P62-LC3 signaling pathway and alleviated endoplasmic reticulum stress by suppressing the IRE1-XBP1s pathway. Consequently, this prevented the downstream activation of the Bcl-2-Bax-Cyt-c-Cleaved Casp-3 apoptotic pathway and the NF-κB inflammatory pathway, ultimately ameliorating RM-AKI. This study lays a strong foundation for the development of metal-polyphenol nanomaterials as a therapeutic strategy for clinical AKI.

Expression and role of CTHRC1 in inflammatory bowel disease in children

Inflammatory bowel disease (IBD) is a chronic, progressive, immune-mediated, gastrointestinal inflammatory disease with increasing occurrences in children. Collagen triple helix repeat containing 1 (CTHRC1), a migration-promoting protein, acts as a tumor-promoting factor in malignant tumors. However, functions and mechanisms of CTHRC1 in children with IBD remain unclear. This study aimed to determine the effects and mechanisms of CTHRC1 on dextran sodium sulfate (DSS)-treated HT-29 cells. HT-29 control cells were exposed to 2% DSS to develop an in vitro IBD model. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blotting were used to assess CTHRC1 expression in serum of children with IBD and HT-29 cells. Cell viability and apoptosis were assessed using MTT and flow cytometry (FCM). Expressions of cleaved-Caspase3 and Caspase3 were determined by western blotting. The cytokine production (TNF-α, IL-1β and IL-6) in HT-29 cells was measured by ELISA assay. Activation or inactivation of NF-κB signaling pathway was confirmed by western blot assay. Results showed that CTHRC1 expression was upregulated in the IBD serum and HT-29 control cells. The level of CTHRC1 was lower in CTHRC1-siRNA transfected cells than in control siRNA-treated cells. Notably, silence of CTHRC1 markedly enhanced HT-29 cells viability, decreased apoptotic cells, suppressed cleaved-Caspase3 expression, inhibited cleaved-Caspase3/Caspase3 ratio, reduced the production of inflammatory cytokines, and blocked NF-κB signaling pathway induced by DSS. However, these effects were reversed following diprovocim treatment. Thus, that knockdown of CTHRC1 alleviated DSS-induced HT-29 cell injury by inhibiting the NF-κB signaling pathway in vitro, providing a new therapeutic target for IBD in children.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10616-025-00705-x.

NAT10 Modulates Atherosclerosis Progression Mediated by Macrophage Polarization Through Regulating ac4C Modification of TLR9

Atherosclerosis (AS) is an inflammatory disease affected by macrophage polarization. N4-acetylcytosine (ac4C) modification mediated by N-acetyltransferase 10 (NAT10). In this study, we aimed to elucidate the role of ac4C modification mediated macrophage polarization in AS through in vivo and in vitro experiments. The ac4C level was measured using dot blot. Macrophage polarization was assessed by quantitative real-time PCR and flow cytometry. Underlying mechanism was analyzed by methylated RNA Immunoprecipitation (MeRIP), RIP and dual luciferase report. Results showed that the NAT10 expression and ac4C level were increased in patients with AS. Additionally, NAT10 knockdown promoted M1 to M2 polarization and suppressed TLR9 ac4C level. TLR9 overexpression reversed macrophage polarization regulated by NAT10 knockdown. Furthermore, M1 polarization and atherosclerosis in vivo was inhibited by NAT10 knockdown. In conclusion, we demonstrated that NAT10 regualted AS progression mediated by macrophage polarization through regulating ac4C modification of TLR9 and provided a new theoretical basis.

NAT10 mediates TLR2 to promote podocyte senescence in adriamycin-induced nephropathy

N-acetyltransferase 10 (NAT10) is involved in regulating senescence. However, its role in glomerular diseases remains unclear. Therefore, this study aims to investigate the mechanisms by which NAT10 influences senescence and damage in an adriamycin (ADR)-induced nephropathy model. Senescence (p16 and p21) and DNA damage markers (γ-H2AX (ser139)) were assessed in ADR-induced nephropathy. NAT10 function was demonstrated using Remodelin or small interfering RNA (siRNA) interventions. Transcriptome sequencing was conducted to identify key downstream genes and pathways, while coimmunoprecipitation was performed to evaluate the relationship between NAT10 and toll-like receptor 2 (TLR2) expression. TLR2 overexpression or knockdown further validated its regulatory role in senescence. In ADR-treated mice, the expression levels of P53, P21, P16, γ-H2AX(S139) proteins were elevated, while those of WT-1 and nephrin were reduced. This effect was mitigated by Remodelin and siNAT10 administration. Transcriptome sequencing identified TLR2 as a key downstream gene, and coimmunoprecipitation, along with molecular docking models, confirmed its interaction with NAT10. TLR2 overexpression plasmid or siRNA was employed for recovery experiments. Together, the study findings suggest that NAT10 contributes to podocyte senescence and injury via interaction with TLR2. Further, it demonstrates that NAT10 alleviates ADR-induced podocyte senescence by interacting with TLR2, potentially through a P53-P21-dependent mechanism. Thus NAT10 could serve as a novel therapeutic target for treating podocyte senescence and proteinuric glomerulopathies.

Biological function and mechanism of NAT10 in cancer

N-acetyltransferase 10 (NAT10) is a nucleolar acetyltransferase with an acetylation catalytic function and can bind various protein and RNA molecules. As the N4-acetylcytidine (ac4C) "writer" enzyme, NAT10 is reportedly involved in a variety of physiological and pathological activities. Currently, the NAT10-related molecular mechanisms in various cancers are not fully understood. In this review, we first describe the cellular localization of NAT10 and then summarize its numerous biological functions. NAT10 is involved in various biological processes by mediating the acetylation of different proteins and RNAs. These biological functions are also associated with cancer progression and patient prognosis. We also review the mechanisms by which NAT10 plays roles in various cancer types. NAT10 can affect tumor cell proliferation, metastasis, and stress tolerance through its acetyltransferase properties. Further research into NAT10 functions and expression regulation in tumors will help explore its future potential in cancer diagnosis, treatment, and prognosis.

Epigenetic regulation of macrophage function in kidney disease: New perspective on the interaction between epigenetics and immune modulation

The interaction between renal intrinsic cells and macrophages plays a crucial role in the onset and progression of kidney diseases. In recent years, epigenetic mechanisms such as DNA methylation, histone modification, and non-coding RNA regulation have become essential windows for understanding these processes. This review focuses on how renal intrinsic cells (including tubular epithelial cells, podocytes, and endothelial cells), renal cancer cells, and mesenchymal stem cells influence the function and polarization status of macrophages through their own epigenetic alterations, and how the epigenetic regulation of macrophages themselves responds to kidney damage, thus participating in renal inflammation, fibrosis, and repair. Moreover, therapeutic studies targeting these epigenetic interaction mechanisms have found that the application of histone deacetylase inhibitors, histone methyltransferase inhibitors, various nanomaterials, and locked nucleic acids against non-coding RNA have positive effects on the treatment of multiple kidney diseases. This review summarizes the latest research advancements in these epigenetic regulatory mechanisms and therapies, providing a theoretical foundation for further elucidating the pathogenesis of kidney diseases and the development of novel therapeutic strategies.

Exploring the impact of N4-acetylcytidine modification in RNA on non-neoplastic disease: unveiling its role in pathogenesis and therapeutic opportunities

RNA modifications include not only methylation modifications, such as m6A, but also acetylation modifications, which constitute a complex interaction involving "writers," "readers," and "erasers" that play crucial roles in growth, genetics, and disease. N4-acetylcytidine (ac4C) is an ancient and highly conserved RNA modification that plays a profound role in the pathogenesis of a wide range of diseases. This review provides insights into the functional impact of ac4C modifications in disease and introduces new perspectives for disease treatment. These studies provide important insights into the biological functions of post-transcriptional RNA modifications and their potential roles in disease mechanisms, offering new perspectives and strategies for disease treatment.

Blood from septic patients with necrotising soft tissue infection treated with hyperbaric oxygen reveal different gene expression patterns compared to standard treatment

BACKGROUND

Sepsis and shock are common complications of necrotising soft tissue infections (NSTI). Sepsis encompasses different endotypes that are associated with specific immune responses. Hyperbaric oxygen (HBO2) treatment activates the cells oxygen sensing mechanisms that are interlinked with inflammatory pathways. We aimed to identify gene expression patterns associated with effects of HBO2 treatment in patients with sepsis caused by NSTI, and to explore sepsis-NSTI profiles that are more receptive to HBO2 treatment.

METHODS

An observational cohort study examining 83 NSTI patients treated with HBO2 in the acute phase of NSTI, fourteen of whom had received two sessions of HBO2 (HBOx2 group), and another ten patients (non-HBO group) who had not been exposed to HBO2. Whole blood RNA sequencing and clinical data were collected at baseline and after the intervention, and at equivalent time points in the non-HBO group. Gene expression profiles were analysed using machine learning techniques to identify sepsis endotypes, treatment response endotypes and clinically relevant transcriptomic signatures of response to treatment.

RESULTS

We identified differences in gene expression profiles at follow-up between HBO2-treated patients and patients not treated with HBO2. Moreover, we identified two patient endotypes before and after treatment that represented an immuno-suppressive and an immune-adaptive endotype respectively, and we characterized the genetic profile of the patients that transition from the immuno-suppressive to the immune-adaptive endotype after treatment. We discovered one gene MTCO2P12 that distinguished individuals who altered their endotype in response to treatment from non-responders.

CONCLUSION

The global gene expression pattern in blood changed in response to HBO2 treatment in a direction associated with clinical biochemistry improvement, and the study provides potential novel biomarkers and pathways for monitoring HBO2 treatment effects and predicting an HBO2 responsive NSTI-sepsis profile.

TRIAL REGISTRATION

Biological material was collected during the INFECT study, registered at ClinicalTrials.gov (NCT01790698) 04/02/2013.

Se-methylselenocysteine inhibits inflammatory response in an LPS-stimulated chicken HD11 macrophage-like cell model through the NFKB2 pathway

Among the various sources of selenium supplementations, the Se-methylselenocysteine (SeMC) is a natural organic selenium compound that has been demonstrated to have multiple advantages in terms of metabolism efficiency and biosafety in animals. Nevertheless, the genome-wide impact of SeMC on gene transcription remains to be elucidated. In this study, we employed an LPS-stimulated chicken HD11 macrophage-like cell model to identify the principal transcription factors involved in transcriptome regulation responsible for SeMC treatment. RNA-seq identified 3,263 transcripts that exhibited a statistically significant differential expression between the SeMC-treated group and the control group and 1,344 transcripts that exhibited a statistically significant differential expression between the LPS + SeMC- and LPS-treated groups (FDR < 0.05, FDR > 1.5). The bioinformatic analysis identified six transcription factors (NFKB2, RFX2, E2F5, ETV5, BACH1, and E2F7) as potential candidate genes for transcriptome regulation in SeMC-treated HD11 cells. Subsequent experimental verification demonstrated that SeMC suppressed the inflammatory response in an LPS-stimulated chicken HD11 cell model via the TXN2-NF-κB pathway. The administration SeMC was observed to reduce the production of ROS as well as the transcription and translation of inflammatory cytokines in both cell culture and in vivo animal studies. One candidate pathway by which SeMC exerts its effects is through the targeting of the transcription factor, NFKB2, by selenoprotein TXN2. This study identified key transcription factors and revealed one of the potential mechanisms through which SeMC exerts its anti-inflammatory effects from the perspective of transcriptional regulation.

Emerging Role of NAT10 as ac4C Writer in Inflammatory Diseases: Mechanisms and Therapeutic Applications

The incidence of inflammatory diseases, including infections, autoimmune disorders, and tumors, is consistently increasing year by year, posing a significant and growing threat to human health on a global scale. Recent research has indicated that RNA acetylation modification, a specific type of post-transcriptional modification, may play a critical role in the pathogenesis of these diseases. Among the various mechanisms of RNA modification, N-acetyltransferase 10 (NAT10) has been identified as the sole cytidine acetyltransferase in eukaryotes. NAT10 is responsible for acetylating mRNA cytosine, which leads to the formation of N4-acetylcytidine (ac4C), a modification that subsequently influences mRNA stability and translation efficiency. Despite these insights, the specific roles and underlying mechanisms by which RNA acetylation contributes to the onset and progression of inflammatory diseases remain largely unclear. This review aimed to elucidate the alterations in NAT10 expression, the modifications it induces in target genes, and its overall contribution to the pathogenesis of various inflammatory conditions. It has been observed that NAT10 expression tends to increase in most inflammatory conditions, thereby affecting the expression and function of target genes through the formation of ac4C. Furthermore, inhibitors targeting NAT10 present promising therapeutic avenues for treating inflammatory diseases by selectively blocking NAT10 activity, thereby preventing the modification of target genes and suppressing immune cell activation and inflammatory responses. This potential for therapeutic intervention underscores the critical importance of further research on NAT10's role in inflammatory disease pathogenesis, as understanding these mechanisms could lead to significant advancements in treatment strategies, potentially transforming the therapeutic landscape for these conditions.

Multifunctional Hydrogel Microneedle Patches Modulating Oxi-inflamm-aging for Diabetic Wound Healing

Oxidative stress, chronic inflammation, and immune senescence are important pathologic factors in diabetic wound nonhealing. This study loads taurine (Tau) into cerium dioxide (CeO2) to develop CeO2@Tau nanoparticles with excellent antioxidant, anti-inflammatory, and anti-aging properties. To enhance the drug penetration efficiency in wounds, CeO2@Tau is encapsulated in gelatin methacryloyl (GelMA) hydrogel to prepare CeO2@Tau@Hydrogel@Microneedle (CTH@MN) patch system. Microneedle technology achieves precise and efficient delivery of CeO2@Tau, ensuring their deep penetration into the wound tissue for optimal efficacy. Rigorous in vitro and in vivo tests have confirmed the satisfactory therapeutic effect of CTH@MN patch on diabetic wound healing. Mechanistically, CTH@MN attenuates oxidative damage and inflammatory responses in macrophages by inhibiting the ROS/NF-κB signaling pathway. Meanwhile, CTH@MN activated autophagy-mediated anti-aging activity, creating a favorable immune microenvironment for tissue repair. Notably, in a diabetic mouse wound model, the multifunctional CTH@MN patch significantly promotes wound healing by systematically regulating the oxidation-inflammation-aging (oxi-inflamm-aging) pathological axis. In conclusion, the in-depth exploration of the CTH@MN system in this study provides new strategies and perspectives for treating diabetic non-healing wounds.

The role and mechanism of NAT10-mediated ac4C modification in tumor development and progression

RNA modification has emerged as a crucial area of research in epigenetics, significantly influencing tumor biology by regulating RNA metabolism. N-acetyltransferase 10 (NAT10)-mediated N4-acetylcytidine (ac4C) modification, the sole known acetylation in eukaryotic RNA, influences cancer pathogenesis and progression. NAT10 is the only writer of ac4C and catalyzes acetyl transfer on targeted RNA, and ac4C helps to improve the stability and translational efficiency of ac4C-modified RNA. NAT10 is highly expressed and associated with poor prognosis in pan-cancers. Based on its molecular mechanism and biological functions, ac4C is a central factor in tumorigenesis, tumor progression, drug resistance, and tumor immune escape. Despite the increasing focus on ac4C, the specific regulatory mechanisms of ac4C in cancer remain elusive. The present review thoroughly analyzes the current knowledge on NAT10-mediated ac4C modification in cancer, highlighting its broad regulatory influence on targeted gene expression and tumor biology. This review also summarizes the limitations and perspectives of current research on NAT10 and ac4C in cancer, to identify new therapeutic targets and advance cancer treatment strategies.

Regulation of ROS metabolism in macrophage via xanthine oxidase is associated with disease progression in pulmonary tuberculosis

BACKGROUND

Pulmonary tuberculosis (PTB) exacerbation can lead to respiratory failure, multi-organ failure, and symptoms related to central nervous system diseases. The purpose of this study is to screen biomarkers and metabolic pathways that can predict the progression of PTB, and to verify the role of the metabolic enzyme xanthine oxidase (XO) in the progression of PTB.

METHODS

To explore the biomarkers and mechanisms underlying the progression of PTB, plasma metabolomics sequencing was conducted on patients with severe PTB, non-severe PTB, and healthy individuals. Screening differential metabolites and metabolic pathways that can predict the progression of PTB, and verifying the function and mechanism of action of XO through experiments.

RESULTS

The purine metabolism, sphingolipid metabolism, and amino acid metabolism between the three groups differ. In patients with severe PTB, the levels of xanthosine and hypoxanthine are increased, while the levels of D-tryptophan, dihydroceramide and uric acid are decreased. Inhibition of XO activity has been observed to reduce the levels of tumor necrosis factor (TNF-α), interleukin-1 beta (IL-1β), and interleukin-6 (IL-6), as well as to suppress the production of reactive oxygen species (ROS) and the activation of the NF-κB pathway, while also promoting the growth of MTB within cells.

CONCLUSION

D-tryptophan, xanthosine, and dihydroceramide can be utilized as biomarkers for progression of PTB, assisting in the evaluation of disease progression, and XO stands out as a potential therapeutic target for impeding the progression of PTB.

NAT10 and cytidine acetylation in mRNA: intersecting paths in development and disease

N4-acetylcytidine (ac4C) is an RNA modification that is catalyzed by the enzyme NAT10. Constitutively found in tRNA and rRNA, ac4C displays a dynamic presence in mRNA that is shaped by developmental and induced shifts in NAT10 levels. However, deciphering ac4C functions in mRNA has been hampered by its context-dependent influences in translation and the complexity of isolating effects on specific mRNAs from other NAT10 activities. Recent advances have begun to overcome these obstacles by leveraging natural variations in mRNA acetylation in cancer, developmental transitions, and immune responses. Here, we synthesize the current literature with a focus on nuances that may fuel the perception of cellular discrepancies toward the development of a cohesive model of ac4C function in mRNA.

Liquid-liquid phase separation in diseases

Liquid-liquid phase separation (LLPS), an emerging biophysical phenomenon, can sequester molecules to implement physiological and pathological functions. LLPS implements the assembly of numerous membraneless chambers, including stress granules and P-bodies, containing RNA and protein. RNA-RNA and RNA-protein interactions play a critical role in LLPS. Scaffolding proteins, through multivalent interactions and external factors, support protein-RNA interaction networks to form condensates involved in a variety of diseases, particularly neurodegenerative diseases and cancer. Modulating LLPS phenomenon in multiple pathogenic proteins for the treatment of neurodegenerative diseases and cancer could present a promising direction, though recent advances in this area are limited. Here, we summarize in detail the complexity of LLPS in constructing signaling pathways and highlight the role of LLPS in neurodegenerative diseases and cancers. We also explore RNA modifications on LLPS to alter diseases progression because these modifications can influence LLPS of certain proteins or the formation of stress granules, and discuss the possibility of proper manipulation of LLPS process to restore cellular homeostasis or develop therapeutic drugs for the eradication of diseases. This review attempts to discuss potential therapeutic opportunities by elaborating on the connection between LLPS, RNA modification, and their roles in diseases.

Emerging roles of RNA ac4C modification and NAT10 in mammalian development and human diseases

RNA ac4C modification is a novel and rare chemical modification observed in mRNA. Traditional biochemical studies had primarily associated ac4C modification with tRNA and rRNA until in 2018, Arango D et al. first reported the presence of ac4C modification on mRNA and demonstrated its critical role in mRNA stability and translation regulation. Furthermore, they established that the ac4C modification on mRNA is mediated by the classical N-acetyltransferase NAT10. Subsequent studies have underscored the essential implications of NAT10 and mRNA ac4C modification across both physiological and pathological regulatory processes. In this review, we aimed to explore the discovery history of RNA ac4C modification, its detection methods, and its regulatory mechanisms in disease and physiological development. We offer a forward-looking examination and discourse concerning the employment of RNA ac4C modification as a prospective therapeutic strategy across diverse diseases. Furthermore, we comprehensively summarize the functions and mechanisms of NAT10 in gene expression regulation and pathogenesis independent of RNA ac4C modification.

The immunotoxicity mechanism of hemocytes in Chlamys farreri incubated with noradrenaline and benzo[a]pyrene-7,8-dihydrodiol-9,10-epoxide alone or in combination

Benzo[a]pyrene-7,8-dihydrodiol-9,10-epoxide (BPDE) is the active intermediate metabolite of benzo[a]pyrene (B[a]P) and is considered the ultimate immunotoxicant. The neuroendocrine immunoregulatory network of bivalves is affected under pollutant stress. Besides, bivalves are frequently affected by pollutants in marine environments, yet the combined effects of neuroendocrine factors and detoxification metabolites on bivalves under pollutant stress and the signal pathways that mediate this immunoregulation are not well understood. Therefore, we incubated the hemocytes of Chlamys farreri with the neuroendocrine factor noradrenaline (NA) and the B[a]P detoxification metabolite BPDE, alone or in combination, to examine the immunotoxic effects of NA and BPDE on the hemocytes in C. farreri. Furthermore, the effects of NA and BPDE on the hemocyte signal transduction pathway were investigated by assessing potential downstream targets. The results revealed that NA and BPDE, alone or in combination, resulted in a significant decrease in phagocytic activity, bacteriolytic activity and the total hemocyte count. In addition, the immunotoxicity induced by BPDE was further exacerbated by co-treatment with NA, and the two showed synergistic effects. Analysis of signaling pathway factors showed that NA activated G proteins by binding to α-AR, which transmitted information to the Ca2+-NF-κB signaling pathway to regulate the expression of phagocytosis-associated proteins and regulated cytokinesis through the cAMP signaling pathway. BPDE could activate PTK and affect phagocytosis and cytotoxicity proteins through Ca2+-NF-κB signal pathway, also affect the regulation of phagocytosis and cytotoxicity by inhibiting the AC-cAMP-PKA pathway to down-regulate the expression of NF-κB and CREB. In addition, BPDE and NA may affect the immunity of hemocytes by down-regulating phagocytosis-related proteins through inhibition of the lectin pathway, while regulating the expression of cytotoxicity-related proteins through the C-type lectin. In summary, immune parameters were suppressed through Ca2+ and cAMP dependent pathways exposed to BPDE and the immunosuppressive effects were enhanced by the neuroendocrine factor NA.

Ameliorative Effect of Ginsenoside Rg6 in Periodontal Tissue Inflammation and Recovering Damaged Alveolar Bone

Periodontal disease is a chronic disease with a high prevalence, and in order to secure natural materials to prevent oral diseases, new materials that protect periodontal tissue from inflammation are being sought. Genes were identified using real-time quantitative polymerase chain reaction (RT-qPCR), and proteins were confirmed using Western blot. Dichlorodihydrofluorescein diacetate (DCF-DA) analysis was used, and the antibacterial effects were confirmed through Minimum Inhibitory Concentration (MIC) and Minimal Bactericidal Concentration (MBC) analysis. To confirm this effect in vivo, Sprague-Dawley rats, in which periodontitis was induced using ligation or Lipopolysaccharide of Porphyromonas gingivalis (PG-LPS), were used. In vitro experiments using human periodontal ligament (HPDL) cells stimulated with PG-LPS showed that Ginsenoside Rg6 (G-Rg6) had anti-inflammatory, antibacterial, antioxidant, and osteoblast differentiation properties. In vivo, G-Rg6 was effective in Sprague-Dawley rats in which periodontitis was induced using ligation or PG-LPS. Therefore, Ginsenoside Rg6 shows potential effectiveness in alleviating periodontitis.

Trimethyltin chloride induces apoptosis and DNA damage via ROS/NF-κB in grass carp liver cells causing immune dysfunction

Trimethyltin chloride (TMT), a common component in fungicides and plastic stabilizers, presents environmental risks, particularly to fish farming. The precise toxicological mechanisms of TMT in L8824 grass carp liver cells remain undefined. Our study investigates TMT's effects on these cells, focusing on its potential to induce hepatotoxicity via oxidative stress and NF-κB pathway activation. First, we selected 0, 3, 6, and 12 μM as the challenge doses, according to the inhibitory concentration of 50% (IC50) of TMT. Our results demonstrate that TMT decreases cell viability dose-dependently and triggers oxidative stress, as evidenced by increased ROS staining and MDA content. Concurrently, it inhibited the antioxidant activities of T-AOC, T-SOD, CAT, and GSH. The activation of the NF-κB pathway was confirmed by gene expression changes. Furthermore, we observed an increase in cell apoptosis rate by AO/EB staining and cell flow cytometry, and the downregulation of Bcl-2 and the upregulation of Bax, Cytc, Caspase-9, and casp3 verified that TMT passed through the BCL2/BAX/casp3 pathway induces apoptosis. DNA damage was validated by the comet assay and γH2AX gene overexpression. Lastly, our data showed increased expression of TNF-α, IL-1β, IL-6, and INF-γ and decreased antimicrobial peptides, validating immune dysfunction. In conclusion, our findings establish that TMT induces apoptosis and DNA damage via ROS/NF-κB in grass carp liver cells, causing immune dysfunction. This study provides novel insights into the toxicology research of TMT and sheds light on the immunological effects of TMT toxicity, enriching our understanding of the immunotoxicity of TMT on aquatic organisms and contributing to the protection of ecosystems.

NAT10 regulates the repair of UVB-induced DNA damage and tumorigenicity

Chemical modifications in messenger RNA (mRNA) regulate gene expression and play critical roles in stress responses and diseases. Recently we have shown that N6-methyladenosine (m6A), the most abundant mRNA modification, promotes the repair of UVB-induced DNA damage by regulating global genome nucleotide excision repair (GG-NER). However, the roles of other mRNA modifications in the UVB-induced damage response remain understudied. N4-acetylcytidine (ac4C) is deposited in mRNA by the RNA-binding acetyltransferase NAT10. This NAT10-mediated ac4C in mRNA has been reported to increase both mRNA stability and translation. However, the role of ac4C and NAT10 in the UVB-induced DNA damage response remains poorly understood. Here we show that NAT10 plays a critical role in the repair of UVB-induced DNA damage lesions through regulating the expression of the key GG-NER gene DDB2. We found that knockdown of NAT10 enhanced the repair of UVB-induced DNA damage lesions by promoting the mRNA stability of DDB2. Our findings are in contrast to the previously reported role of NAT10-mediated ac4C deposition in promoting mRNA stability and may represent a novel mechanism for ac4C in the UVB damage response. Furthermore, NAT10 knockdown in skin cancer cells decreased skin cancer cell proliferation in vitro and tumorigenicity in vivo. Chronic UVB irradiation increases NAT10 protein levels in mouse skin. Taken together, our findings demonstrate a novel role for NAT10 in the repair of UVB-induced DNA damage products by decreasing the mRNA stability of DDB2 and suggest that NAT10 is a potential novel target for preventing and treating skin cancer.