HDAC inhibitor sodium butyrate prevents allergic rhinitis and alters lncRNA and mRNA expression profiles in the nasal mucosa of mice

The role of histone deacetylases in inflammatory respiratory diseases: an update

INTRODUCTION

Histone deacetylases (HDACs) catalyze the removal of acetyl groups from lysine residues of histones and other proteins, generally leading to a closed chromosomal configuration and transcriptional repression. Different HDACs have distinct substrate specificities and functions in different biological processes. Accumulating evidence indicates that HDACs play a key role in the pathogenesis of multiple respiratory diseases.

AREAS COVERED

After an extensive search of the PubMed database, Web of Science and ClinicalTrials.gov, covering the period from 1992 to 2024, this review summarizes recent advances in understanding the role of HDACs in inflammatory respiratory diseases, including allergic rhinitis (AR), chronic rhinosinusitis (CRS), asthma and chronic obstructive pulmonary disease (COPD). We also examine recent progress on the efficacy and potential use of histone deacetylase inhibitors (HDACi) for the treatment of these diseases.

EXPERT OPINION

Available data indicate that HDACs play an important role in the development of common inflammatory respiratory diseases, and HDACi have shown promise as treatments for these diseases. However, the exact roles and underlying mechanisms of specific HDACs in disease pathogenesis require further study. Additional work is necessary to develop novel potent HDACi with high isoform selectivity.

Sphk1 regulates HMGB1 via HDAC4 and mediates epithelial pyroptosis in allergic rhinitis

Background

Allergic rhinitis (AR) is a global health issue affecting millions of individuals worldwide. Pyroptosis has emerged as a major player in the development of AR, and targeting its inhibition with specific drugs holds promise for AR treatment. However, a comprehensive understanding of the precise mechanisms underlying pyroptosis in AR remains to be explored, warranting further investigation.

Objective

This study aims to elucidate the roles of HMGB1, Sphk1, and HDAC4 in regulating human nasal epithelial cell (hNEC) pyroptosis and AR.

Methods

An in vitro AR cell culture model and an in vivo AR mouse model were established. Western blot, ELISA, histological staining, and flow cytometry were utilized to confirm the gene and protein expression. The interactions among Sphk1, HDAC4, and HMGB1 were validated through ChIP, Co-IP, and Dual-luciferase assay.

Results and conclusion

We identified that the expression levels of Sphk1, HMGB1, and inflammasome components, including IL-18, and IL-1β were elevated in AR patients and mouse models. Knockdown of Sphk1 inhibited hNEC pyroptosis induced by dust mite allergen. Overexpression of HDAC4 suppressed HMGB1-mediated pyroptosis in hNECs. In addition, HDAC4 was found to mediate the transcriptional regulation of HMGB1 via MEF2C, a transcription factor. Additionally, Sphk1 was shown to interact with CaMKII-δ, promoting the phosphorylation of HDAC4 and inhibiting its cytoplasmic translocation. Knockdown of HDAC4 reversed the effect of Sphk1 knockdown on pyroptosis. These discoveries offer a glimpse into the molecular mechanisms underlying AR and suggest potential therapeutic targets for the treatment of this condition.

Histone acetylation regulated by histone deacetylases during spermatogenesis

BACKGROUND

Physical, chemical, and biological factors in the environment constantly influence in vivo and in vitro biological processes, including diverse histone modifications involved in cancer and metabolism. However, the intricate mechanisms of acetylation regulation remain poorly elucidated. In mammalian spermatogenesis, acetylation plays a crucial role in repairing double-strand DNA breaks, regulating gene transcription, and modulating various signaling pathways.

RESULTS

This review summarizes the histone acetylation sites in the mouse testis and provides a comprehensive overview of how histone acetylation is involved in different stages of spermatogenesis under the regulation by histone deacetylases. The regulatory functions of various class histone deacetylases during spermatogenesis and the crossroad between histone acetylation and other histone modifications are highlighted. It is imperative to understand the mechanisms of histone acetylation regulated by histone deacetylases in spermatogenesis, which facilitates to prevent and treat infertility-related diseases.

An antioxidant ameliorates allergic airway inflammation by inhibiting HDAC 1 via HIF-1α/VEGF axis suppression in mice

Histone deacetylase inhibitors (HDACi) are novel class of drugs as they are involved in post translational modification of several proteins involved in signaling pathways related to asthma. HDACi have been reported to elicit protective effects on asthma but the signaling pathways associated with it have not been investigated much. Recently, we have demonstrated that intranasal administrations of Pan-HDAC inhibitors, sodium butyrate and curcumin, which have effectively reduced asthma severity via HDAC1 inhibition in Ovalbumin induced mouse model. Present study aimed to investigate possible pathways by which curcumin and sodium butyrate may minimize asthma pathogenesis via HDAC 1 inhibition. Balb/c mice were exposed (sensitized and challenged) with Ovalbumin to establish allergic asthma model followed by pretreatment of curcumin (5 mg/kg) and sodium butyrate (50 mg/kg) through intranasal route. Effects of curcumin and sodium butyrate on HIF-1α/VEGF signaling through activation of PI3K/Akt axis has been investigated using protein expressions followed by chromatin immunoprecipitation of BCL2 and CCL2 against HDAC1. Molecular docking analysis was also performed to investigate effects of curcumin and butyrate on mucus hypersecretion, goblet cell hyperplasia and airway hyperresponsiveness. Augmented expressions of HDAC-1, HIF-1α, VEGF, p-Akt and p-PI3K were observed in asthmatic group which was suppressed in both the treatments. NRF-2 level was significantly restored by curcumin and butyrate treatments. Protein expressions of p-p38, IL-5 and mRNA expressions of GATA-3 were also reduced in curcumin and butyrate treatment groups. Our findings suggest that curcumin and sodium butyrate may attenuate airway inflammation via down regulation of p-Akt/p-PI3K/HIF-1α/VEGF axis.

Vancomycin-induced gut microbiota dysbiosis aggravates allergic rhinitis in mice by altered short-chain fatty acids

OBJECTIVE

This study aims to explore how gut microbiota dysbiosis affects allergic rhinitis (AR) and whether short-chain fatty acids (SCFAs) play a role in this process.

METHODS

A mouse gut microbiota dysbiosis model was established by adding vancomycin to drinking water for 2 weeks before ovalbumin (OVA) sensitization. Then an OVA-alum AR mouse model was established by intraperitoneal OVA injection followed by nasal excitation. Hematoxylin and eosin (H&E) staining was performed to observe pathological changes in nasal and colon tissues of AR mice. Serum levels of total-IgE, OVA-sIgE, IL-4, IL-5, IL-10, and TGF-β1 were measured. The composition and diversity of the mouse gut microbiota were observed by 16S rDNA sequencing. Levels of SCFAs in feces were determined using SCFA-targeted metabolomics. Sodium butyrate (NaB) was added daily to mice on a low-fiber basal diet 2 weeks before the first sensitization, until the end of the study.

RESULTS

After gut microbiota dysbiosis, serum levels of the total IgE, OVA-sIgE, IL-4, and IL-5 in AR mice were significantly increased, compared with the control group. The composition and diversity of gut microbiota were significantly altered after gut microbiota dysbiosis, with the fecal SCFAs significantly reduced as well. The reduced bacterial genera after gut microbiota dysbiosis, such as Ruminococcus and Lactobacillus, were significantly and positively correlated with SCFAs. In contrast, the increased genera in the Van group, such as Escherichia-Shigella and Klebsiella, were significantly negatively correlated with SCFAs in feces. NaB treatment significantly reduced total-IgE, OVA-sIgE, IL-4, and IL-5 levels in serum, and inflammatory infiltration of the nasal and colon mucosa. In addition, serum levels of IL-10 and TGF-β1 increased significantly after NaB treatment. Foxp3 protein in the colon was upregulated considerably after NaB intervention.

CONCLUSION

Vancomycin-induced gut microbiota dysbiosis increased susceptibility and severity of AR, which is significantly related to reduced SCFA-producing bacteria, fecal SCFAs, and specific bacterial taxa. In addition, it was found that NaB alleviated low dietary fiber base-fed symptoms and immune status in AR mice.

The emerging role of histone deacetylase 1 in allergic diseases

Histone deacetylase 1 (HDAC1) is a unique member of the classes I HDACs and helps to regulate acute and chronic adaptation to environmental stimuli such as allergen, stress. Allergic diseases are complex diseases resulting from the effect of multiple genetic and interacting foreign substances. Epigenetics play an important role in both pathological and immunomodulatory conditions of allergic diseases. To be consistent with this role, recent evidence strongly suggests that histone deacetylase 1 (HDAC1) plays a critical role in allergic response. HDAC1 expression is stimulated by allergen and attributes to increase T helper 2 (Th2) cytokine levels, decrease Th1/Th17 cells and anti-inflammatory cytokine Interleukin-10 (IL-10), and TWIK-related potassium channel-1 (Trek-1) expression. This review focuses on the contribution of HDAC1 and the regulatory role in characterizing allergic endotypes with common molecular pathways and understanding allergic multimorbidity relationships, as well as addressing their potential as therapeutic targets for these conditions.

Short-chain fatty acid: An updated review on signaling, metabolism, and therapeutic effects

Fatty acids are good energy sources (9 kcal per gram) that aerobic tissues can use except for the brain (glucose is an alternative source). Apart from the energy source, fatty acids are necessary for cell signaling, learning-related memory, modulating gene expression, and functioning as cytokine precursors. Short-chain fatty acids (SCFAs) are saturated fatty acids arranged as a straight chain consisting minimum of 6 carbon atoms. SCFAs possess various beneficial effects like improving metabolic function, inhibiting insulin resistance, and ameliorating immune dysfunction. In this review, we discussed the biogenesis, absorption, and transport of SCFA. SCFAs can act as signaling molecules by stimulating G protein-coupled receptors (GPCRs) and suppressing histone deacetylases (HDACs). The role of SCFA on glucose metabolism, fatty acid metabolism, and its effect on the immune system is also reviewed with updated details. SCFA possess anticancer, anti-diabetic, and hepatoprotective effects. Additionally, the association of protective effects of SCFA against brain-related diseases, kidney diseases, cardiovascular damage, and inflammatory bowel diseases were also reviewed. Nanotherapy is a branch of nanotechnology that employs nanoparticles at the nanoscale level to treat various ailments with enhanced drug stability, solubility, and minimal side effects. The SCFA functions as drug carriers, and nanoparticles were also discussed. Still, much research was not focused on this area. SCFA functions in host gene expression through inhibition of HDAC inhibition. However, the study has to be focused on the molecular mechanism of SCFA against various diseases that still need to be investigated.

Prediction of the Mechanism of Sodium Butyrate against Radiation-Induced Lung Injury in Non-Small Cell Lung Cancer Based on Network Pharmacology and Molecular Dynamic Simulations and Molecular Dynamic Simulations

Background

Radiation-induced lung injury (RILI) is a severe side effect of radiotherapy for non-small cell lung cancer (NSCLC) ,and one of the major hindrances to improve the efficacy of radiotherapy. Previous studies have confirmed that sodium butyrate (NaB) has potential of anti-radiation toxicity. However, the mechanism of the protective effect of NaB against RILI has not yet been clarified. This study aimed to explore the underlying protective mechanisms of NaB against RILI in NSCLC through network pharmacology, molecular docking, molecular dynamic simulations and in vivo experiments.

Methods

The predictive target genes of NaB were obtained from the PharmMapper database and the literature review. The involved genes of RILI and NSCLC were predicted using OMIM and GeneCards database. The intersectional genes of drug and disease were identified using the Venny tool and uploaded to the Cytoscape software to identify 5 core target genes of NaB associated with RILI. The correlations between the 5 core target genes and EGFR, PD-L1, immune infiltrates, chemokines and chemokine receptors were analyzed using TIMER 2.0, TIMER and TISIDB databases. We constructed the mechanism maps of the 3 key signaling pathways using the KEGG database based on the results of GO and KEGG analyses from Metascape database. The 5 core target genes and drug were docked using the AutoDock Vina tool and visualized using PyMOL software. GROMACS software was used to perform 100 ns molecular dynamics simulation. Irradiation-induced lung injury model in mice were established to assess the therapeutic effects of NaB.

Results

A total of 51 intersectional genes involved in NaB against RILI in NSCLC were identified. The 5 core target genes were AKT1, TP53, NOTCH1, SIRT1, and PTEN. The expressions of the 5 core target genes were significantly associated with EGFR, PD-L1, immune infiltrates, chemokines and chemokine receptors, respectively. The results from GO analysis of the 51 intersectional genes revealed that the biological processes were focused on the regulation of smooth muscle cell proliferation, oxidative stress and cell death, while the three key KEGG pathways were enriched in PI3K-Akt signal pathway, p53 signal pathway, and FOXO signal pathway. The docking of NaB with the 5 core target genes showed affinity and stability, especially AKT1. In vivo experiments showed that NaB treatment significantly protected mice from RILI, with reduced lung histological damage. In addition, NaB treatment significantly inhibited the PI3K/Akt signaling pathway.

Conclusions

NaB may protect patients from RILI in NSCLC through multiple target genes including AKT1, TP53, NOTCH1, SIRT1 and PTEN, with multiple signaling pathways involving, including PI3K-Akt pathway, p53 pathway, and FOXO pathways. Our findings effectively provide a feasible theoretical basis to further elucidate the mechanism of NaB in the treatment of RILI.

Shukri N, Wong KK, Mohd Ashari NS. Zonula occludens-1 expression is reduced in nasal epithelial cells of allergic rhinitis patients

Allergic rhinitis (AR) is a common allergic disease characterized by disruption of nasal epithelial barrier. In this study, we investigated the mRNA expression of zonula occludens-1 (ZO-1), ZO-2 and ZO-3 and histone deacetylase 1 (HDAC1) and HDAC2 in AR patients compared to healthy controls. RNA samples were extracted from nasal epithelial cells of house dust mites (HDMs)-sensitized AR patients and healthy controls (n = 28 in each group). The RNAs were reverse transcribed into cDNAs for measurement of ZO-1, ZO-2, ZO-3, HDAC1 and HDAC2 expression levels by quantitative PCR. The mRNA expression of ZO-1 was significantly decreased in AR patients compared to healthy controls (p = 0.010). No significant difference was observed in the expression levels of ZO-2, ZO-3, HDAC1 and HDAC2 in AR patients compared to healthy controls. We found significant associations of higher HDAC2 levels in AR patients with lower frequency of changing bedsheet (p = 0.043) and with AR patients sensitized to Dermatophagoides farinae (p = 0.041). Higher expression of ZO-2 was observed in AR patients who had pets (p = 0.007). In conclusion, our data indicated that ZO-1 expression was lower in AR patients contributing to decreased integrity of nasal epithelial barrier integrity, and HDAC2 may be involved in the pathogenesis of the disease.

The Role of Defective Epithelial Barriers in Allergic Lung Disease and Asthma Development

The respiratory epithelium constitutes the physical barrier between the human body and the environment, thus providing functional and immunological protection. It is often exposed to allergens, microbial substances, pathogens, pollutants, and environmental toxins, which lead to dysregulation of the epithelial barrier and result in the chronic inflammation seen in allergic diseases and asthma. This epithelial barrier dysfunction results from the disturbed tight junction formation, which are multi-protein subunits that promote cell-cell adhesion and barrier integrity. The increasing interest and evidence of the role of impaired epithelial barrier function in allergy and asthma highlight the need for innovative approaches that can provide new knowledge in this area. Here, we review and discuss the current role and mechanism of epithelial barrier dysfunction in developing allergic diseases and the effect of current allergy therapies on epithelial barrier restoration.

[Research progress on the relationship between lncRNA and the pathogenesis of allergic rhinitis]

Long non-coding RNA（lncRNA） belongs to the category of non-coding RNA, which length exceeds 200 nucleotides and can hardly encode the expression of proteins. Based on the data from several clinical researches, it is considered that lncRNA not only plays the biological role in epigenetics, transcriptional and post-transcriptional levels, but also abnormally expresses in inflammatory response and the related diseases. In recent years, with the intensive study of gene expression regulation of allergic rhinitis（AR）, it has been found that a variety of non-coding RNA, including lncRNA, have close relationship with the occurrence and development of AR. This review mainly summarized the biological function, immunomodulatory effect of lncRNA and the relationship between the lncRNA and the pathogenesis of AR, providing new thoughts and strategies for the further research, prevention as well as the treatment of AR.

Sulforaphane attenuates cisplatin-induced hearing loss by inhibiting histone deacetylase expression

INTRODUCTION

Cruciferous vegetables are a rich source of sulforaphane (SFN), which acts as a natural HDAC inhibitor (HDACi). Our previous study found that HDACi could restore histone acetyltransferase/histone deacetylase (HAT/HDAC) balance in the cochlea and attenuate gentamicin-induced hearing loss in guinea pigs. Here, we investigated the protective effect of SFN on cisplatin-induced hearing loss (CIHL).

METHODS

Thirty rats were randomly divided into 3 equal groups: the control group, cisplatin group, and SFN+cisplatin group. Rats were injected with SFN (30 mg/kg once a day) and cisplatin (7 mg/kg twice a day) for 7 days to investigate the protective role of SFN on CIHL. We observed auditory brainstem response (ABR) threshold shifts and immunostained cochlear basilar membranes of rats. For in vitro experiments, we treated HEI-OC1 cells and rat cochlear organotypic cultures with SFN (5, 10, and 15 μM) and cisplatin (10 μM). Immunofluorescence, cell viability, and protein analysis were performed to further analyze the protective mechanism of SFN on CIHL.

RESULTS

SFN (30 mg/kg once a day) decreased cisplatin (7 mg/kg twice a day)-induced ABR threshold shifts and outer hair cell loss. CCK-8 assay showed that cisplatin (10 μM) reduced the viability of HEI-OC1 cells to 42%, and SFN had a dose-dependent protective effect. In cochlear organotypic cultures, we found that SFN (10 and 15 μM) increased cisplatin (10 μM)-induced myosin 7a⁺ cell count and restored ciliary morphology. SFN (5, 10, and 15 μM) reversed the cisplatin (10 μM)-induced increase in HDAC2, -4, and -5 and SFN (15 μM) reversed the cisplatin (10 μM)-induced decrease in H3-Ack9 [acetyl-histone H3 (Lys9)] protein expression in HEI-OC1 cells. Neither cisplatin nor cisplatin combined with SFN affected the expression of HDAC7, or HDAC9.

CONCLUSION

SFN prevented disruption of the HAT/HDAC balance, protecting against CIHL in rats.