Home Selective HDAC8 inhibition by PCI-34051 attenuates inflammation and airway remodeling in asthma via miR-381-3p-TGFβ3 axis
Article Open Access

Selective HDAC8 inhibition by PCI-34051 attenuates inflammation and airway remodeling in asthma via miR-381-3p-TGFβ3 axis

  • Shiyao Bai , Xinming Su EMAIL logo , Delei Kong , Chenye Feng , Xiaochun Zhang , Ying Pan , Jieyu Zhao , Jiamin Sun and Wenyang Li EMAIL logo
Published/Copyright: January 10, 2025
Download Article (PDF)
Journal of Translational Internal Medicine
From the journal Journal of Translational Internal Medicine Volume 12 Issue 6

Abstract

Background and Objectives

Histone deacetylase (HDAC) families regulate various physical processes and the development of several diseases. The role of HDACs in asthma development and progression worths further investigation. This study aims to evaluate the effect of HDACs in a mouse model of asthma.

Methods

HDAC8 selective inhibitor PCI-34051 was administered to a mouse model of ovalbumin-sensitized and challenged asthma. Airway responsiveness, serum cytokines, histological changes of the airway, and expression levels of α-SMA, β-actin, VEGFR, VEGF, GAPDH, HDAC8, TGF-β3, CD 105, p-ERK 1/2, ERK 1/2, PI3K, p-AKT, AKT, and PDK1 were evaluated. The miR-381-3p level was also measured.

Results

All classic histologic and cellular changes of asthma in inflammation and airway remodeling were altered by HDAC8 inhibitor PCI-34051 via regulation of the miR-381-3p level and its downstream gene, TGF-β3. Inhibition of TGF-β3 further reduced the activation of ERK, PI3K, AKT, and PDK1.

Conclusion

In a mouse model, HDAC8 inhibitor PCI-34051 exhibits comprehensive control of asthmatic changes, including inflammation and airway remodeling.

Key words: asthma; airway remodeling; histone deacetylase; inflammation; microRNA

Introduction

Asthma is typically characterized by chronic airway inflammation. This common respiratory disease affects an estimated 300 million people worldwide, and its prevalence is increasing.[1] Even with consistent clinical presentations, including wheezing, shortness of breath, and chest tightness, indicating airflow limitation, asthma is a heterogeneous disease that is difficult to define, diagnose, assess severity, and manage.[2] Current asthma control strategies rely mainly on glucocorticoids and longacting β2 agonists.[3] However, using the available treatments, the disease is not well controlled in many patients, probably because of diverse pathogenic processes. Rather than being viewed as a single disease entity, asthma is now considered a clinical condition involving multiple pathological mechanisms. The underlying mechanisms can be classified into inflammation and airway remodeling. Developing new targeted therapies tailored to specific epigenotypes may be necessary for leveraging more detailed knowledge for better management through individualized treatment of these two key contributors to asthma.

The histone deacetylase (HDAC) family includes four classes of nuclear enzymes capable of modifying chromatin structure by removing acetyl functional groups from lysine residues of target proteins. HDACs regulate various physical processes, including the cell cycle, differentiation, and apoptosis.[4] In the pathogenesis of respiratory diseases, increased HDAC expression has been reported in chronic obstructive pulmonary disease,[5] allergic rhinitis[6,7,8] and asthma.[9,10] The role of HDACs in asthma development and progression in particular warrants further investigation. Because HDAC activity is reversible by pan- or specific inhibitors, the therapeutic effects of HDAC inhibitors have been evaluated in several diseases. Moreover, to better understand the disease mechanism, HDAC inhibitors can be used to clarify the function of each molecule involved in pathogenesis and the associations between the molecules.

In this study, the selective HDAC8 inhibitor PCI-34051 was administered to mice in an ovalbumin (OVA)-sensitized and challenged asthma model aiming to determine the role of HDAC8 in asthma development and explore the potential pathways involved. These results may help identify novel treatment targets and benefit the asthma population.

Materials and methods

Development of OVA-sensitized and challenged asthma model

The study protocol was reviewed and approved by our hospital’s Institutional Animal Care and Use Committee (approval number AF-SOP-07-1.1-01). The OVA asthma model was used in the present study, as previously described.[11,12] Briefly, SPF-grade female BABL/c mice aged 6–8 weeks and weighing 20 ± 2 g were housed in an SPF-grade room for one week and provided water and food ad libitum. Mice were randomly divided into four groups (n = 6 for each group): healthy control (con), mice with asthma (ova), dexamethasone treatment (dex), and PCI-34051 treatment (pci). Mice of the ova, dex, and pci groups were sensitized by intraperitoneal injection of 0.2 mL OVA solution (20 μg OVA and 2 mg aluminum hydroxide [both Sigma-Aldrich, St. Louis, MO, USA] in 0.2 mL normal saline) at days 0, 7, and 14 to create the asthma model. The OVA challenge was conducted on day 21 using a 2% OVA saline solution with a nebulizer for 30 min daily, three times per week for eight weeks, while mice in the control group were administered saline. In the dex and pci groups, dexamethasone (2 mg/kg, Sigma-Aldrich) and PCI-34051 (0.5 mg/kg, Sigma-Aldrich), respectively, were administered intraperitoneally before each challenge, and the con and ova groups were administered saline as a control.

Airway responsiveness measurement

Airway resistance was estimated using noninvasive wholebody plethysmography (Emka Technologies, Paris, France). An enhanced pause (Penh) was recorded for 3 minutes following the administration of acetyl-β-methylcholine chloride (Sigma-Aldrich) at concentrations of 0, 3.125, 6.25, 12.5, 25, and 50 mg/mL, as previously described.[13] Cytokine measurementSerum samples were prepared from blood collected by orbital puncture after anesthesia (2.5% isoflurane delivered in O2, 2 L/minute) and centrifuged at 3500 rpm (with centrifugal radius 10 cm) at 4°C for 15 minutes. Cytokine levels, including IL-17/IL-17A, IL-17E/ IL-25, IL-6, IL-13, and TNF-α, were measured by Luminex - based immunoassays.

Lung tissue preparation

Anesthetized mice were sacrificed by cervical dislocation 1 hour after the last OVA challenge. The left lung was fixed with 0.1 mL iced 4% polyoxymethylene, removed, and fixed in 4% polyoxymethylene for 24 hours. After rehydration by running tap water for 6 hours, dehydration and embedding in paraffin were performed, and 4 μm sections were cut for further analysis.

Histopathological analysis

Inflammation levels were evaluated by HE staining and a 5-point scoring system. Fibrosis levels were evaluated by collagen deposition or basement membrane thickness using Masson’s trichrome staining. As determined by PAS staining, mucus metaplasia was evaluated based on the percentage of mucus-containing goblet cells.

Immunofluorescence staining

The sections were incubated with blocking solution (Beyotime Biotechnology, Shanghai, China) for 1 hour and then incubated overnight with the primary antibodies α-SMA and CD 31 (both Abcam, Cambridge, MA, USA) at 4°C and for 1 hour with Alexa Fluor-labeled secondary antibodies (Abcam) at 37°C. Nuclei were stained with DAPI (Abcam, Cambridge, UK). The stained sections were observed using a fluorescence microscope (Olympus, Tokyo, Japan).

Western blotting

Proteins were extracted with RIPA buffer, and concentrations were measured using a BCA protein concentration kit (Beyotime Biotechnology). Equal amounts of proteins were subjected to gel electrophoresis and transferred to polyvinylidene fluoride membranes. After blocking, membranes were incubated with the primary antibodies α-SMA, -actin, VEGFR, VEGF, GAPDH, HDAC8, TGF-3, CD 105, p-ERK 1/2, ERK 1/2, PI3K, p-AKT, AKT, and PDK1, followed by incubation with the corresponding HRP-conjugated secondary antibodies (all Abcam). The immunoblots were visualized using enhanced chemiluminescence (Bio-Rad, Hercules, CA, USA). Densitometry was performed using the ImageJ software (National Institutes of Health, Bethesda, Maryland, USA).

Immunohistochemistry

The sections were deparaffinized, hydrated, subjected to antigen retrieval, and then incubated with the following primary antibodies: VEGF, VEGFR, TGF-3, CD 105, ERK 1/2, and AKT, and the corresponding biotinylated secondary antibodies (all Abcam). Color development was performed using a DAB solution (Vector Laboratories, Burlingame, CA, USA), and the sections were counterstained with Mayer’s hematoxylin.

Real-time quantitative RT-PCRTotal RNA was extracted using TRIzol (Invitrogen, Carlsbad, CA, USA) according to the manufacturer’s instructions. cDNA was synthesized using a reverse transcription kit (Roche, Shanghai, China), and RT-qPCR was performed using SYBR Green-based reagent and amplified on a CFX real-time PCR detection system (Bio-Rad). U6 and GAPDH were internal references for miR-381-3p and VEGFR and VEGF mRNA, respectively.

Fluorescence in situ hybridization analysis

Sections were blocked with 3% BSA in 4× saline-sodium citrate, then treated with proteinase K (Roche), and hybridized with FITC-labeled miR-381-3p probe and stained with anti-digoxin rhodamine conjugate (Abcam) at 37°C for 1 hour in the dark. Nuclei were stained with DAPI (Abcam), and stained sections were observed under a fluorescence microscope (Olympus).

Results

The Penh values increased with increasing concentrations of acetyl-β-methylcholine in all groups, and the value in the OVA group was significantly higher than in the other groups, indicating that the Penh value changed to near normal (con group) when mice received treatment (including the dex and pci groups). The airway resistance at the fixed dose of 50 mg/mL acetyl-β-methylcholine chloride showed the same effect (Figure 1A). HDAC8 inhibition reduced inflammation, fibrosis, and mucus secretion as evaluated by HE, Masson’s trichrome, and PAS staining, respectively (Figure 1B). HDAC8 expression correlated with the pathogenesis of asthma, as the expression level increased in the ova group and decreased in the dex and pci groups, as evaluated by western blotting (Figure 1C).

Figure 1 HDAC8 expression in airway related to asthma in ovalbumin-sensitized and challenged BALB/c mouse model. A. Enhanced Penh value was observed after asthma induction and significantly reduced to normal level by dexamethasone and HDAC 8 inhibitor. B. Results of HE, Masson’s trichrome, and Periodic Acid-Schiff staining indicated that the inflammation level, collagen deposition and mucus secretion cell numbers significantly increased in the asthmatic airway, and both dexamethasone and HDAC 8 inhibitor reversed these changes. C. Increased HDAC8 was found in the asthmatic airway and significantly decreased by dexamethasone and HDAC 8 inhibitor, detected by Western blot. Con: control group; ova: ovalbumin induction group; dex: dexamethasone treatment group; pci: PCI-34051 treatment group; PAS: Periodic Acid-Schiff staining. *P < 0.05, **P < 0.01, ***P < 0.001 and ****P < 0.0001 respectively compared to the con group. ##P < 0.01, ###P < 0.001 and ####P < 0.0001 respectively compared to the ova group.
Figure 1

HDAC8 expression in airway related to asthma in ovalbumin-sensitized and challenged BALB/c mouse model. A. Enhanced Penh value was observed after asthma induction and significantly reduced to normal level by dexamethasone and HDAC 8 inhibitor. B. Results of HE, Masson’s trichrome, and Periodic Acid-Schiff staining indicated that the inflammation level, collagen deposition and mucus secretion cell numbers significantly increased in the asthmatic airway, and both dexamethasone and HDAC 8 inhibitor reversed these changes. C. Increased HDAC8 was found in the asthmatic airway and significantly decreased by dexamethasone and HDAC 8 inhibitor, detected by Western blot. Con: control group; ova: ovalbumin induction group; dex: dexamethasone treatment group; pci: PCI-34051 treatment group; PAS: Periodic Acid-Schiff staining. *P < 0.05, **P < 0.01, ***P < 0.001 and ****P < 0.0001 respectively compared to the con group. ##P < 0.01, ###P < 0.001 and ####P < 0.0001 respectively compared to the ova group.

Levels of the important Th 2 inflammatory cytokines IL-17A, IL-17E, IL-6, IL-13, and TNF-α were significantly increased in the ova group, compared to the con group (P < 0.0001) and significantly decreased in the dex and pci groups compared to the ova group (P < 0.0001 for all in the pci group, P < 0.001 for IL-17/IL-17A in the dex group and P < 0.0001 for the others in the dex group), indicating that HDAC8 inhibition reduces Th2-mediated airway inflammation (Figure 2).

Figure 2 Changes of inflammatory cytokine levels in serum. IL-17/IL-17A, IL-17E/IL-25, IL-6, IL-13, and TNF-α significantly increased in asthma and decreased by dexamethasone and HDAC 8 inhibitor treatment. Con: control group; ova: ovalbumin induction group; dex: dexamethasone treatment group; pci: PCI-34051 treatment group. ****P < 0.0001 compared to the con group. ###P < 0.001 and ####P < 0.0001 respectively compared to the ova group.
Figure 2

Changes of inflammatory cytokine levels in serum. IL-17/IL-17A, IL-17E/IL-25, IL-6, IL-13, and TNF-α significantly increased in asthma and decreased by dexamethasone and HDAC 8 inhibitor treatment. Con: control group; ova: ovalbumin induction group; dex: dexamethasone treatment group; pci: PCI-34051 treatment group. ****P < 0.0001 compared to the con group. ###P < 0.001 and ####P < 0.0001 respectively compared to the ova group.

Figure 3 shows the effects of HDAC8 inhibition on airway remodeling through the expression of α-SMA and CD 31, which represent the structural response of airway smooth muscle cells and the microvasculature in asthma. Immunofluorescence staining and western blotting indicated that HDAC8 inhibition reduced the number of smooth muscle and endothelial cells. These results indicate that HDAC8 inhibition may reduce the thickening of vessel walls and neovascularization in asthma. The percentages of vascular wall area, vascular endothelial cell numbers, and neogenetic microvessel density were all significantly increased in mice in the ova group compared to those in the con group (P < 0.001 for the percentage of vascular wall area, P < 0.0001 for the other two). After receiving treatments, mice of the dex and pci groups showed significant reductions in all three indicators, compared to those in the ova group (P < 0.05; Figure 3A). The protein expression of α-SAM significantly increased in mice of the ova group compared to those in the con group (P < 0.0001). Both decreased significantly in mice of the dex and pci groups, compared to those in the ova group (P < 0.0001). However, the expression of α-SMA in the dex and pci groups was still significantly higher than that of the con group (P < 0.001; Figure 3B).

Figure 3 Airway remodeling in asthma was inhibited by dexamethasone and HDAC8 inhibitor. A. Immunofluorescence staining of α-SMA (red) and CD 31 (green) showed the smooth muscle hyperplasia in the arteries and neovascularization closed to the asthmatic airway decreased by dexamethasone and HDAC 8 inhibitor treatment. B. Results of western blot indicated that α-SMA expression increased in asthma significantly decreased by dexamethasone and HDAC 8 inhibitor treatment. Con: control group; ova: ovalbumin induction group; dex: dexamethasone treatment group; pci: PCI-34051 treatment group. ***P < 0.001 and ****P < 0.0001 respectively compared to the con group. #P < 0.05, ##P < 0.01, ###P < 0.001 and ####P < 0.0001 respectively compared to the ova group.
Figure 3

Airway remodeling in asthma was inhibited by dexamethasone and HDAC8 inhibitor. A. Immunofluorescence staining of α-SMA (red) and CD 31 (green) showed the smooth muscle hyperplasia in the arteries and neovascularization closed to the asthmatic airway decreased by dexamethasone and HDAC 8 inhibitor treatment. B. Results of western blot indicated that α-SMA expression increased in asthma significantly decreased by dexamethasone and HDAC 8 inhibitor treatment. Con: control group; ova: ovalbumin induction group; dex: dexamethasone treatment group; pci: PCI-34051 treatment group. ***P < 0.001 and ****P < 0.0001 respectively compared to the con group. #P < 0.05, ##P < 0.01, ###P < 0.001 and ####P < 0.0001 respectively compared to the ova group.

Evaluation of VEGF and VEGFR, which are involved in Th2-mediated airway inflammation and angiogenesis in asthma, demonstrated that HDAC8 inhibition reduced the protein and mRNA levels of VEGF and VEGFR (Figure 4). Immunohistochemical staining showed that VEGF expression was significantly increased in mice of the ova group compared to those of the con group (P < 0.0001) and significantly reduced in those of the dex and pci groups compared to the ova group (P < 0.0001; Figure 4A). Western blotting indicated that both VEGFR and VEGF expression increased significantly in the ova group compared to in the con group (P < 0.05, P < 0.0001, respectively). VEGF expression decreased significantly in the dex and pci groups compared to the ova group (P < 0.05 and P < 0.01, respectively). However, the levels were still significantly higher than in the con group (P < 0.0001 and P < 0.001, respectively). VEGFR expression decreased significantly in the dex and pci groups compared to in the ova group (P < 0.01 and P < 0.05, respectively; Figure 4B). Changes in the mRNA expression of VEGF and VEGFR showed similar trends as the western blot results (Figure 4C).

Figure 4 VEGF and VEGFR increased in asthma and decreased by dexamethasone and HDAC 8 inhibitor. A. Immunohistochemical staining. B. Western blot. C. Quantitative RT-PCR. Con: control group; ova, ovalbumin induction group; dex: dexamethasone treatment group; pci: PCI-34051 treatment group; AOD: average optical density. *P < 0.05, **P < 0.01, ***P < 0.001 and ****P < 0.0001 respectively compared to the con group. #P < 0.05, ##P < 0.01 and ####P < 0.0001 respectively compared to the ova group.
Figure 4

VEGF and VEGFR increased in asthma and decreased by dexamethasone and HDAC 8 inhibitor. A. Immunohistochemical staining. B. Western blot. C. Quantitative RT-PCR. Con: control group; ova, ovalbumin induction group; dex: dexamethasone treatment group; pci: PCI-34051 treatment group; AOD: average optical density. *P < 0.05, **P < 0.01, ***P < 0.001 and ****P < 0.0001 respectively compared to the con group. #P < 0.05, ##P < 0.01 and ####P < 0.0001 respectively compared to the ova group.

The miR-381-3-p levels were significantly lower than those in the control group (P < 0.0001). When mice received the HDAC8 inhibitor, PCI-34051, miR-381-3-p expression in the asthmatic airway was significantly higher than in the con group (P < 0.0001) or ova group (P < 0.0001), indicating that HDAC8 may be associated with miR-381-3-p expression in the lungs, as represented by the FISH and quantitative RT-PCR data (Figure 5). The levels of miR-381-3-p-regulated molecules TGF-β3 and CD 105 increased in the ova group and decreased in the dex and pci groups (Figure 6). Immunohistochemistry staining of TGF-β3 showed that the expression significantly increased in the mice of the ova group compared to those of the con group (P < 0.0001) and was significantly reduced in those of the dex and pci groups compared to the ova group (P < 0.0001). Western blotting revealed similar results (Figure 6A). Immunohistochemical staining of CD 105 showed that its expression significantly increased in mice of the ova group compared to those of the con group (P < 0.0001) and was significantly reduced in those of the dex and pci groups compared to the ova group (P < 0.0001). Western blotting revealed similar results (Figure 6B).

Figure 5 Decreased miR-381-3p in asthmatic airway was reversed and increased significantly after HDAC 8 inhibitor treatment. A. Fluorescence in situ hybridization. B. Quantitative RT-PCR. Con: control group; ova: ovalbumin induction group; dex: dexamethasone treatment group; pci: PCI-34051 treatment group. ****P < 0.0001 compared to the con group. ####P < 0.0001 compared to the ova group.
Figure 5

Decreased miR-381-3p in asthmatic airway was reversed and increased significantly after HDAC 8 inhibitor treatment. A. Fluorescence in situ hybridization. B. Quantitative RT-PCR. Con: control group; ova: ovalbumin induction group; dex: dexamethasone treatment group; pci: PCI-34051 treatment group. ****P < 0.0001 compared to the con group. ####P < 0.0001 compared to the ova group.

Figure 6 TGF-β3 and CD105 levels increased in asthma and decreased by dexamethasone and HDAC 8 inhibitor. Protein levels were evaluated by immunohistochemical staining and western blot. A. TGF-β3. B. CD105. Con: control group; ova: ovalbumin induction group; dex: dexamethasone treatment group; pci: PCI-34051 treatment group. ***P < 0.001 and ****P < 0.0001 respectively compared to the con group. ###P < 0.001 and ####P < 0.0001 compared to the ova group.
Figure 6

TGF-β3 and CD105 levels increased in asthma and decreased by dexamethasone and HDAC 8 inhibitor. Protein levels were evaluated by immunohistochemical staining and western blot. A. TGF-β3. B. CD105. Con: control group; ova: ovalbumin induction group; dex: dexamethasone treatment group; pci: PCI-34051 treatment group. ***P < 0.001 and ****P < 0.0001 respectively compared to the con group. ###P < 0.001 and ####P < 0.0001 compared to the ova group.

In the ova group, the expression of p-ERK1/2, ERK 1/2, PI3K, p-AKT, AKT, and PDK1 was higher than that in the con group. The levels of all proteins decreased in the dex and pci groups (Figure 7), and immunohistochemical staining of p-ERK 1/2 showed that the expression was significantly increased in mice of the ova group compared to those of the con group (P < 0.0001) and significantly reduced in those of the dex and pci groups, compared to the ova group (P < 0.0001). Western blotting revealed similar results (Figure 7A). Immunohistochemical staining of AKT showed that the expression was significantly increased in mice of the ova group compared to those of the con group (P < 0.0001) and significantly reduced in those of the dex and pci groups compared to the ova group (P < 0.0001; Figure 7B). Western blotting results showed significant increases in PI3K (P < 0.05), p-AKT (P < 0.05), and PDK1 (P < 0.0001) levels in mice in the ova group compared to those in the con group. After both dexamethasone and PCI-34051treatments, the expression levels of PI3K (P < 0.01), p-AKT (P < 0.05), and PDK1 (P < 0.0001) were significantly reduced in the ova group (Figure 7B).

Figure 7 HDAC 8 involved in asthma via ERK and PI3K/AKT pathways. These proteins evaluated by immunohistochemical staining and western blot increased in the asthmatic airway and reduced significantly after dexamethasone and HDAC 8 inhibitor treatment. A. ERK1/2. B. PI3K, AKT, and PDK1. Con: control group; ova: ovalbumin induction group; dex: dexamethasone treatment group; pci: PCI-34051 treatment group. *P < 0.05, **P < 0.01 and ****P < 0.0001 respectively compared to the con group. #P < 0.05, ##P < 0.01, ###P < 0.001 and ####P < 0.0001 compared to the ova group.
Figure 7

HDAC 8 involved in asthma via ERK and PI3K/AKT pathways. These proteins evaluated by immunohistochemical staining and western blot increased in the asthmatic airway and reduced significantly after dexamethasone and HDAC 8 inhibitor treatment. A. ERK1/2. B. PI3K, AKT, and PDK1. Con: control group; ova: ovalbumin induction group; dex: dexamethasone treatment group; pci: PCI-34051 treatment group. *P < 0.05, **P < 0.01 and ****P < 0.0001 respectively compared to the con group. #P < 0.05, ##P < 0.01, ###P < 0.001 and ####P < 0.0001 compared to the ova group.

Discussion

This study’s results have shown that TGF-β3 plays a central role in regulating both the signaling of inflammation and airway remodeling in a mouse model of asthma. The HDAC8 inhibitor PCI-34051 altered all classic histologic and cellular changes of asthma via regulation of the miR-381-3p level and its downstream gene TGF-β3. Inhibition of TGF-β3 further reduced the activation of ERK, PI3K, AKT, and PDK1.

Inflammation and airway remodeling play vital roles in asthma’s occurrence and progression, both of which are multicellular processes. Eosinophils, T cells, mast cells, neutrophils, and dendritic cells are recruited to the site of asthmatic inflammation. Structural changes in the airway, including epithelial fragility, goblet cell metaplasia, fibroblast hyperplasia, airway smooth muscle mass increase, and basement membrane thickening due to collagen deposition, are all significant typical features of asthma. The crosstalk between inflammation and airway remodeling is closed and frequent; inflammation leads to airway remodeling via factors secreted by inflammatory cells, including cytokines, chemokines, and growth factors, and drives changes in the structural cells of the airway,[14] which also produce factors that increase immune cell levels in the airway. For example, airway smooth muscle cells produce IL-6, which is required for IL-17A expression and promotes Th17 polarization.[15,16] Interactions between immune cells and airway structural cells increase the complexity of pathogenesis, asthma epigenotypes, and disease control because the treatment target is difficult to identify.[14,17]

MicroRNAs (miRs) are single-stranded RNA molecules that range from 19 to 24 nucleotides in length and are known to be involved in several important physical functions via post-transcriptional regulation of target gene expression. In addition, the role of miRNAs in the pathogenesis of many diseases has been investigated.[18,19,20,21] In a 4,4’-methylene diphenyl diisocyanate-induced occupational asthma (OA) mouse model, a 2- to 5-fold downregulation of circulating miR-381-3p has been observed in mice of the OA group compared to those of the control group. Pathway analysis results have indicated that miR-381-3p may be associated with immune system regulation.[22] However, a definitive mechanism has not yet been evaluated in this OA model. Our previous in vitro study found that miR-381-3p overexpression in human bronchial smooth muscle cells decreased the expression of α-SMA, fibronectin 1, and collagen I, which are all markers of airway remodeling, suggesting that miR-381-3p may be a moderator of airway remodeling in asthma.[23]HDAC8 belongs to class I HDACs. Since HDAC8 overexpression has been observed in several malignancies[24,25,26] and respiratory diseases, including asthma,[5,6,7,8,9,10] it has become a novel therapeutic target for these diseases. HDAC8 selective inhibitor PCI-34051, with > 200-fold selectivity over other class I HDACs, has been tested for its therapeutic effects in mouse models of asthma, demonstrating that PCI-34051 reduces inflammation and airway remodeling in asthma. Treatment with PCI-34051 ameliorates airway hyperresponsiveness by reducing immune cell counts in bronchoalveolar lavage fluid, significantly decreasing inflammatory cell infiltration and cytokine levels, and reducing M2 macrophage polarization in lung tissue in a mouse model of asthma.[5,10,27,28,29] The antiairway remodeling function of PCI-34051 in asthma has been reported to regulate smooth muscle differentiation and contraction, decrease α-SMA expression, and reduce fibrosis in EMT, bronchial smooth muscle cells hyperplasia, and collagen deposition.[23,28,29]

An investigation of the effects of PCI-34051-induced bronchial epithelial cell-derived exosomes revealed that miR-381-3p expression was upregulated in human bronchial smooth muscle cells.[23] Further genetic analysis and dual-luciferase reporter assay results indicated that TGF-β3 is the target of miR-381-3p after HDAC8 inhibitor PCI-34051 treatment. This is consistent with the results of the present study, which demonstrated that the miR-381-3p level increased and TGF-β3 expression decreased in response to treatment with PCI-34051.

The TGF-β superfamily are key molecules in the asthma signaling pathway, as they are primary mediators of proinflammatory responses and fibrotic tissue remodeling in the lungs. TGF-β, produced by epithelial cells, eosinophils, macrophages, and fibroblasts, is involved in epithelial transformation, fibrosis, airway smooth muscle proliferation, and microvascular changes associated with airway wall thickness, mucus production, collagen deposition, and cytokine dysregulation. These effects are observed in allergenic asthma models, including OVA sensitization and challenge and house dust mite induction models.[30,31] IL-13 induces TGF-β expression and then increases α-SMA expression, collagen deposition, and IL-6 production.[32,33] IL-6 induces VEGF expression and promotes neovascularization in asthma.[15,34,35] These changes were observed in the present study, and it may be concluded that TGF-β3 plays a central role in regulating inflammation signaling and airway remodeling in asthma. Furthermore, this signal may be amplified because not only TGF-β3 but also the receptor increased since the level of one of the components of the TGF-β3 receptor (CD105) in the ova group was elevated.

The TGF-β-centered signaling pathway has been investigated in several studies. It has been reported that TGF-β1 regulates airway smooth muscle hyperplasia in asthma via phosphorylation of PI3K and ERK, which both induce airway smooth muscle cell proliferation.[36,37] In this study, PCI-34051 treatment recovered the increases of TGF-β3, p-ERK, ERK, PI3K, p-AKT, AKT, and PDK1 in the asthmatic airway to normal levels, indicating the important role of HDAC8 in asthma, and the potential therapeutic effect of HDAC8 inhibitor PCI-34051 by controlling the key modulator TGF-β3.

Conclusion

In a mouse model, the HDAC8 inhibitor PCI-34051 exhibited comprehensive control of asthmatic changes, including inflammation and airway remodeling. PCI-34051 altered all classic histologic and cellular changes in inflammation and airway remodeling of asthma by regulating the miR-381-3p level and its downstream gene, TGF-β3. Inhibiting TGF-β3, as a key moderator of asthma occurrence and progression, reduces the activation of ERK, PI3K, AKT, and PDK1. This may improve asthma conditions through reduced airway responsiveness, inflammation infiltration, fibrosis, mucus secretion, microvasculature changes, and Th2 inflammatory cytokines, including IL-17A, IL-17E, IL-6, IL-13, and TNF-α.

Address for Correspondence: Wenyang Li, Department of Respiratory and Critical Care Medicine, The First Hospital of China Medical University, 155 North Nanjing Street, Shenyang 110001, Liaoning Province, China.
Xinming Su, Department of Respiratory and Critical Care Medicine, The First Hospital of China Medical University, 155 North Nanjing Street, Shenyang 110001, Liaoning Province, China.

Funding statement: This work was supported by the National Natural Science Foundation of China [grant number 82170038]; China International Medical Foundation [grant number Z-2017-24-2301]; Youth Program of the National Natural Science Foundation of China [grant number 82002219]; National Science and Technology Major Project [grant number 2022YFC2304604].

Acknowledgements

None.

  1. Author Contributions

    Shiyao Bai: study design, literature research, experimental studies, data analysis, statistical analysis and manuscript preparation; Xinming Su: research integrity, study concepts, study design, definition of intellectual content, manuscript editing and manuscript review; Delei Kong: experimental studies and statistical analysis; Chenye Feng: experimental studies and statistical analysis; Xiaochun Zhang: literature research; Jieyu Zhao: literature research and experimental studies; Jiamin Sun: experimental studies; Ying Pan: experimental studies; Wenyang Li: study design and manuscript editing.

  2. Ethical Approval

    This study protocol was reviewed and approved by the institutional animal care use committee (IACUC) of our hospital, approval number AF-SOP-07-1.1-01.

  3. Informed Consent

    Not applicable.

  4. Conflict of Interest

    All authors declare that there is no conflict of interest.

  5. Data Availability Statement

    The data that support the findings of this study are available from the corresponding author upon reasonable request.

References

1 (GINA) GIfA. Global Strategy for Asthma Management and Prevention. 2022. Available from: https://ginasthma.org/.Search in Google Scholar

2 Borish L, Culp J. Asthma: A syndrome composed of heterogeneous diseases. Ann Allergy Asthma Immunol 2008;101:1-83.10.1016/S1081-1206(10)60826-5Search in Google Scholar PubMed

3 Louis R, Demarche S, Schleich F. A historical perspective: Are inhaled corticoids sufficient to control asthma? J Transl Int Med 2015;3:113-115.10.1515/jtim-2015-0014Search in Google Scholar PubMed PubMed Central

4 de Ruijter AJ, van Gennip AH, Caron HN, Kemp S, van Kuilenburg AB. Histone deacetylases (HDACs): characterization of the classical HDAC family. Biochem J 2003;370:737-749.10.1042/bj20021321Search in Google Scholar

5 Ito K, Ito M, Elliott WM, Cosio B, Caramori G, Kon OM, et al. Decreased histone deacetylase activity in chronic obstructive pulmonary disease. N Engl J Med 2005;352:1967-1976.10.1056/NEJMoa041892Search in Google Scholar PubMed

6 Shao JB, Luo XQ, Wu YJ, Li MG, Hong JY, Mo LH, et al. Histone deacetylase 11 inhibits interleukin 10 in B cells of subjects with allergic rhinitis. Int Forum Allergy Rhinol 2018;8:1274-1283.10.1002/alr.22171Search in Google Scholar PubMed

7 Jiang J, Liu JQ, Li J, Li M, Chen HB, Yan H, et al. Trek1 contributes to maintaining nasal epithelial barrier integrity. Sci Rep 2015;5:9191.10.1038/srep09191Search in Google Scholar PubMed PubMed Central

8 Wang J, Cui M, Sun F, Zhou K, Fan B, Qiu JH, et al. HDAC inhibitor sodium butyrate prevents allergic rhinitis and alters lncRNA and mRNA expression profiles in the nasal mucosa of mice. Int J Mol Med 2020;45:1150-1162.10.3892/ijmm.2020.4489Search in Google Scholar PubMed PubMed Central

9 Wang C, Li H, Cao L, Wang G. Identification of differentially expressed genes associated with asthma in children based on the bioanalysis of the regulatory network. Mol Med Rep 2018;18:2153-2163.10.3892/mmr.2018.9205Search in Google Scholar PubMed PubMed Central

10 Su XM, Ren Y, Li ML, Zhao X, Kong LF, Kang J. Performance evaluation of histone deacetylases in lungs of mice exposed to ovalbumin aerosols. J Physiol Pharmacol 2018;69.Search in Google Scholar

11 Temelkovski J, Hogan SP, Shepherd DP, Foster PS, Kumar RK. An improved murine model of asthma: selective airway inflammation, epithelial lesions and increased methacholine responsiveness following chronic exposure to aerosolised allergen. Thorax 1998;53:849-856.10.1136/thx.53.10.849Search in Google Scholar PubMed PubMed Central

12 Lee M, Kim S, Kwon OK, Oh SR, Lee HK, Ahn K. Anti-inflammatory and anti-asthmatic effects of resveratrol, a polyphenolic stilbene, in a mouse model of allergic asthma. Int Immunopharmacol 2009;9:418-424.10.1016/j.intimp.2009.01.005Search in Google Scholar PubMed

13 Hamelmann E, Schwarze J, Takeda K, Oshiba A, Larsen GL, Irvin CG, et al. Noninvasive measurement of airway responsiveness in allergic mice using barometric plethysmography. Am J Respir Crit Care Med 1997;156:766-775.10.1164/ajrccm.156.3.9606031Search in Google Scholar PubMed

14 Sumi Y, Hamid Q. Airway remodeling in asthma. Allergol Int 2007;56:341-348.10.2332/allergolint.R-07-153Search in Google Scholar PubMed

15 Hollins F, Kaur D, Yang W, Cruse G, Saunders R, Sutcliffe A, et al. Human airway smooth muscle promotes human lung mast cell survival, proliferation, and constitutive activation: Cooperative roles for CADM1, stem cell Factor, and IL-6. J Immunol 2008;181:2772.10.4049/jimmunol.181.4.2772Search in Google Scholar PubMed PubMed Central

16 Kleinschek MA, Owyang AM, Joyce-Shaikh B, Langrish CL, Chen Y, Gorman DM, et al. IL-25 regulates Th17 function in autoimmune inflammation. J Exp Med 2007;204:161-170.10.1084/jem.20061738Search in Google Scholar PubMed PubMed Central

17 Choy DF, Modrek B, Abbas AR, Kummerfeld S, Clark HF, Wu LC, et al. Gene expression patterns of th2 inflammation and intercellular communication in asthmatic airways. J Immunol 2011;186:1861.10.4049/jimmunol.1002568Search in Google Scholar PubMed PubMed Central

18 Mendell JT, Olson EN. MicroRNAs in stress signaling and human disease. Cell 2012;148:1172-1187.10.1016/j.cell.2012.02.005Search in Google Scholar PubMed PubMed Central

19 Paulmurugan R. MicroRNAs - a new generation molecular targets for treating cellular diseases. Theranostics 2013;3:927-929.10.7150/thno.8113Search in Google Scholar PubMed PubMed Central

20 Bartel DP. MicroRNAs: target recognition and regulatory functions. Cell 2009;136:215-233.10.1016/j.cell.2009.01.002Search in Google Scholar PubMed PubMed Central

21 Xiao Y, Zhu H, Lei J, Xie J, Wu K, Gu W, et al. MiR-182/Sestrin2 affects the function of asthmatic airway smooth muscle cells by the AMPK/ mTOR pathway. J Transl Int Med 2023;11:282-293.10.2478/jtim-2021-0033Search in Google Scholar

22 Lin CC, Law BF, Siegel PD, Hettick JM. Circulating miRs-183-5p, -206-3p and -381-3p may serve as novel biomarkers for 4,4’-methylene diphenyl diisocyanate exposure. Biomarkers 2019;24:76-90.10.1080/1354750X.2018.1508308Search in Google Scholar PubMed PubMed Central

23 Bai SY, Li ML, Ren Y, Su XM. HDAC8-inhibitor PCI-34051-induced exosomes inhibit human bronchial smooth muscle cell proliferation via miR-381-3p mediated TGFB3. Pulm Pharmacol Ther 2021;71:102096.10.1016/j.pupt.2021.102096Search in Google Scholar PubMed

24 Chakrabarti A, Oehme I, Witt O, Oliveira G, Sippl W, Romier C, et al. HDAC8: a multifaceted target for therapeutic interventions. Trends Pharmacol Sci 2015;36:481-492.10.1016/j.tips.2015.04.013Search in Google Scholar PubMed

25 Vanaja GR, Ramulu HG, Kalle AM. Overexpressed HDAC8 in cervical cancer cells shows functional redundancy of tubulin deacetylation with HDAC6. Cell Commun Signal 2018; 16: 20.10.1186/s12964-018-0231-4Search in Google Scholar PubMed PubMed Central

26 Wang ZT, Chen ZJ, Jiang GM, Wu YM, Liu T, Yi YM, et al. Histone deacetylase inhibitors suppress mutant p53 transcription via HDAC8/YY1 signals in triple negative breast cancer cells. Cell Signal 2016;28:506-515.10.1016/j.cellsig.2016.02.006Search in Google Scholar PubMed

27 Bosnar M, Ergovic G, Hrvacic B, Frka Boric K, Paravic Radicevic A, Glojnaric I, et al. The histone-deacetylase-8 selective inhibitor PCI-34051 enhances IFN-λ production in vitro and reduces inflammation in mouse models of rhinoviral infection and rhinovirus-induced exacerbations of asthma in vivo. Eur Respir J 2013;42:1972.Search in Google Scholar

28 Li ML, Su XM, Ren Y, Zhao X, Kong LF, Kang J. HDAC8 inhibitor attenuates airway responses to antigen stimulus through synchronously suppressing galectin-3 expression and reducing macrophage-2 polarization. Respir Res 2020;21:62.10.1186/s12931-020-1322-5Search in Google Scholar PubMed PubMed Central

29 Ren Y, Su X, Kong L, Li M, Zhao X, Yu N, et al. Therapeutic effects of histone deacetylase inhibitors in a murine asthma model. Inflamm Res 2016;65:995-1008.10.1007/s00011-016-0984-4Search in Google Scholar PubMed PubMed Central

30 Bottoms SE, Howell JE, Reinhardt AK, Evans IC, McAnulty RJ. TGF-β isoform specific regulation of airway inflammation and remodelling in a murine model of asthma. PLOS ONE 2010;5:e9674.10.1371/journal.pone.0009674Search in Google Scholar PubMed PubMed Central

31 Li G, Fox J, Liu Z, Liu J, Gao GF, Jin Y, et al. Lyn Mitigates mouse airway remodeling by downregulating the TGF-β3 isoform in house dust mite models. J Immunol 2013;191:5359.10.4049/jimmunol.1301596Search in Google Scholar PubMed PubMed Central

32 Firszt R, Francisco D, Church TD, Thomas JM, Ingram JL, Kraft M. Interleukin-13 induces collagen type-1 expression through matrix metalloproteinase-2 and transforming growth factor-β1 in airway fibroblasts in asthma. Eur Respir J 2014;43:464.10.1183/09031936.00068712Search in Google Scholar PubMed PubMed Central

33 Halwani R, Al-Muhsen S, Al-Jahdali H, Hamid Q. Role of transforming growth factor-β in airway remodeling in asthma. Am J Respir Cell Mol Biol 2011;44:127-133.10.1165/rcmb.2010-0027TRSearch in Google Scholar PubMed

34 Kobayashi T, Liu X, Wen F-Q, Fang Q, Abe S, Wang XQ, et al. Smad3 mediates TGF-β1 induction of VEGF production in lung fibroblasts. Biochem Bioph Res Co 2005;327:393-398.10.1016/j.bbrc.2004.12.032Search in Google Scholar PubMed

35 Michaeloudes C, Sukkar MB, Khorasani NM, Bhavsar PK, Chung KF. TGF-β regulates Nox4, MnSOD and catalase expression, and IL-6 release in airway smooth muscle cells. Am. J. Physiol. Lung Cell Mol. Physiol 2011; 300: L295-L304.10.1152/ajplung.00134.2010Search in Google Scholar PubMed PubMed Central

36 Chen G, Khalil N. TGF-beta1 increases proliferation of airway smooth muscle cells by phosphorylation of map kinases. Respir Res 2006;7:2.10.1186/1465-9921-7-2Search in Google Scholar PubMed PubMed Central

37 Xie S, Sukkar MB, Issa R, Khorasani NM, Chung KF. Mechanisms of induction of airway smooth muscle hyperplasia by transforming growth factor-beta. Am J Physiol Lung Cell Mol Physiol 2007;293:L245-L253.10.1152/ajplung.00068.2007Search in Google Scholar PubMed PubMed Central

Published Online: 2025-01-10

© 2024 Shiyao Bai, Xinming Su, Delei Kong, Chenye Feng, Xiaochun Zhang, Ying Pan, Jieyu Zhao, Jiamin Sun, Wenyang Li, published by De Gruyter on behalf of the SMP

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Articles in the same Issue

  1. Perspective
  2. Prospects for the application of artificial intelligence in geriatrics
  3. Artificial intelligence for disease X: Progress and challenges
  4. Secondary prevention for intracranial atherosclerotic stenosis: Where we stand and challenges ahead
  5. Intratumoral microbiota in orchestrating cancer immunotherapy response
  6. Review Article
  7. Gene therapy in polycystic kidney disease: A promising future
  8. Original Article
  9. A Notch signaling pathway-related gene signature: Characterizing the immune microenvironment and predicting prognosis in hepatocellular carcinoma
  10. Development and validation of web-based risk score predicting prognostic nomograms for elderly patients with primary colorectal lymphoma: A population-based study
  11. Association of life’s essential 8 with prevalence and all-cause mortality of chronic kidney disease among US adults: Results from the National Health and Nutrition Examination Survey (2015–2018)
  12. Selective HDAC8 inhibition by PCI-34051 attenuates inflammation and airway remodeling in asthma via miR-381-3p-TGFβ3 axis
  13. Computational analyses to reveal the key determinants of the high malignancy level of cholangiocarcinoma
  14. Letter to Editor
  15. Effectiveness and safety of Qixuekang Oral Liquid on vascular health
https://doi.org/10.1515/jtim-2023-0135
Keywords for this article
asthma; airway remodeling; histone deacetylase; inflammation; microRNA
Creative Commons
BY-NC-ND 4.0

Articles in the same Issue

  1. Perspective
  2. Prospects for the application of artificial intelligence in geriatrics
  3. Artificial intelligence for disease X: Progress and challenges
  4. Secondary prevention for intracranial atherosclerotic stenosis: Where we stand and challenges ahead
  5. Intratumoral microbiota in orchestrating cancer immunotherapy response
  6. Review Article
  7. Gene therapy in polycystic kidney disease: A promising future
  8. Original Article
  9. A Notch signaling pathway-related gene signature: Characterizing the immune microenvironment and predicting prognosis in hepatocellular carcinoma
  10. Development and validation of web-based risk score predicting prognostic nomograms for elderly patients with primary colorectal lymphoma: A population-based study
  11. Association of life’s essential 8 with prevalence and all-cause mortality of chronic kidney disease among US adults: Results from the National Health and Nutrition Examination Survey (2015–2018)
  12. Selective HDAC8 inhibition by PCI-34051 attenuates inflammation and airway remodeling in asthma via miR-381-3p-TGFβ3 axis
  13. Computational analyses to reveal the key determinants of the high malignancy level of cholangiocarcinoma
  14. Letter to Editor
  15. Effectiveness and safety of Qixuekang Oral Liquid on vascular health
Sign up now to receive a 20% welcome discount
Institutional Access
How does access work?
Have an idea on how to improve our website?
Please write us.
© 2025 De Gruyter Brill
Downloaded on 12.9.2025 from https://www.degruyterbrill.com/document/doi/10.1515/jtim-2023-0135/html
Scroll to top button