HDAC1-3 inhibitor MS-275 enhances IL10 expression in RAW264.7 macrophages and reduces cigarette smoke-induced airway inflammation in mice

Abstract

Chronic obstructive pulmonary disease (COPD) constitutes a major health burden. Studying underlying molecular mechanisms could lead to new therapeutic targets. Macrophages are orchestrators of COPD, by releasing pro-inflammatory cytokines. This process relies on transcription factors such as NF-κB, among others. NF-κB is regulated by lysine acetylation; a post-translational modification installed by histone acetyltransferases and removed by histone deacetylases (HDACs). We hypothesized that small molecule HDAC inhibitors (HDACi) targeting class I HDACs members that can regulate NF-κB could attenuate inflammatory responses in COPD via modulation of the NF-κB signaling output. MS-275 is an isoform-selective inhibitor of HDAC1-3. In precision-cut lung slices and RAW264.7 macrophages, MS-275 upregulated the expression of both pro- and anti-inflammatory genes, implying mixed effects. Interestingly, anti-inflammatory IL10 expression was upregulated in these model systems. In the macrophages, this was associated with increased NF-κB activity, acetylation, nuclear translocation, and binding to the IL10 promoter. Importantly, in an in vivo model of cigarette smoke-exposed C57Bl/6 mice, MS-275 robustly attenuated inflammatory expression of KC and neutrophil influx in the lungs. This study highlights for the first time the potential of isoform-selective HDACi for the treatment of inflammatory lung diseases like COPD.

Targeting Transcription Factor Lysine Acetylation in Inflammatory Airway Diseases

“…Thus, MS-275 gives rise to either pro-or anti-inflammatory effects in these cells. In line with this, we demonstrated that MS-275 gives rise to mixed effects on pro-and anti-inflammatory gene expression in RAW264.7 macrophages with upregulation of both pro-and antiinflammatory genes [71]. Importantly, MS-275 increased anti-inflammatory IL10 expression, and we identified NF-κB as a regulator.…”

“…This mechanism is in line with literature that describes that LPS stimulation of macrophages activates NF-κB, which induces the expression of IL10 along with TNFα, IL1β and IL12b [72], which is further enhanced by MS-275 in our study. Upon testing MS-275 in a mouse COPD (cigarette smoke exposure) model, anti-inflammatory effects were observed on several parameters including increased anti-inflammatory IL10 expression in lung macrophages, reduced KC (murine IL-8) expression and reduced neutrophilic influx upon MS-275 treatment, which is the first time that anti-inflammatory effects of an HDACi are being reported in a COPD mouse model [71].…”

“…This illustrates that individual HDACs have specific roles in the control of anti-inflammatory IL10 expression (with HDAC11 as an interesting possible target due to its inhibitory role in IL10 expression), and in the inhibition of CXCL8 expression by IL-10 in these cells. NF-κB/macrophages HDAC1-3 inhibitor MS-275 Ambiguous effects [66][67][68][69][70][71] NF-κB/macrophages HDAC3 inhibitor RGFP966 Attenuation of Inflammation [74] GATA3/Th2 cells SIRT1 inhibitor Sirtinol Increased Th2 related expression in T cells from cord blood; and in PBMCs from severe asthmatics Enhanced acetylation and activity of the GATA3 transcription factor in HUT78 T lymphocytes [83] GATA3/Th2 cells SIRT1 activator (SRT2172) Reduced IL-4 mRNA expression in PBMCs from ten patients with severe asthma [83] Foxp3/Tregs HDAC6i ACY-738 and SIRT1 inhibitor EX-527Increased Treg suppressive function (in combination and alone) EX-527 increased acetylation of K31, K262 and K267, and increased the stability and levels of the transcription factor [91,96] Foxp3/Tregs HDAC1-3 inhibitor MS-275 Ambiguous effects [98][99][100] RORγt/Th17 HDAC1-3 inhibitor MS-275 Enhanced Th17 differentiation in mouse splenocytes [106] RORγt/Th17 Pan HDACi givinostat Downregulated the IL-6 receptor on T cells that reduced their ability to differentiate into Th17 cells, but instead skewed differentiation toward the Treg phenotype [107] Foxp3 and RORγt Pan HDACi TSA Increased Foxp3 and decreased RoRγt levels in an ovalbumin challenge asthma mouse model [38] …”

“…This illustrates that individual HDACs have specific roles in the control of anti-inflammatory IL10 expression (with HDAC11 as an interesting possible target due to its inhibitory role in IL10 expression), and in the inhibition of CXCL8 expression by IL-10 in these cells. NF-κB/macrophages HDAC1-3 inhibitor MS-275 Ambiguous effects [66][67][68][69][70][71] NF-κB/macrophages HDAC3 inhibitor RGFP966 Attenuation of Inflammation [74] GATA3/Th2 cells SIRT1 inhibitor Sirtinol Increased Th2 related expression in T cells from cord blood; and in PBMCs from severe asthmatics Enhanced acetylation and activity of the GATA3 transcription factor in HUT78 T lymphocytes [83] GATA3/Th2 cells SIRT1 activator (SRT2172) Reduced IL-4 mRNA expression in PBMCs from ten patients with severe asthma [83] Foxp3/Tregs HDAC6i ACY-738 and SIRT1 inhibitor EX-527…”

“…Epigenomics (2017) 9(7) future science group Review van den Bosch, Kwiatkowski, Bischoff & Dekker moter activity, acetylation, nuclear translocation and NF-κB p65 binding to the IL10 promoter in RAW264.7 macrophages [71]. This mechanism is in line with literature that describes that LPS stimulation of macrophages activates NF-κB, which induces the expression of IL10 along with TNFα, IL1β and IL12b [72], which is further enhanced by MS-275 in our study.…”