FOXA2 attenuates lipopolysaccharide­induced pneumonia by inhibiting the inflammatory response, oxidative stress and apoptosis through blocking of p38/STAT3 signaling.

Pneumonia is a severe inflammatory disease of the lung. Forkhead box protein A2 (FOXA2) has been demonstrated to serve an important regulatory role in various pulmonary diseases; however, the role of FOXA2 in pneumonia remains to be elucidated. The present study aimed to explore the functional effects and regulatory mechanism of FOXA2 in pneumonia. An in vitro pneumonia model was induced using lipopolysaccharide (LPS) in WI-38 cells. The mRNA and protein expression levels of FOXA2 were determined by reverse transcription-quantitative PCR and western blotting, respectively. Cell viability was assessed using a Cell Counting Kit-8 assay. Inflammatory cytokines were evaluated using ELISA kits and oxidative stress markers were assessed using a malondialdehyde assay kit, superoxide dismutase assay kit and CATalase assay kit. Cell apoptosis was evaluated using flow cytometry and the caspase3 activity was determined. Western blotting was performed to examine the protein expression levels of endoplasmic reticulum stress (ERS)-associated factors. For a rescue assay, a p38 MAPK activator, U46619, was used to investigate the regulatory mechanism of FOXA2 involving p38/STAT3 signaling. FOXA2 was downregulated in LPS-induced WI-38 cells. FOXA2 overexpression alleviated LPS-induced inflammation, oxidative stress, apoptosis and ERS in WI-38 cells. Furthermore, the inhibitory effects of FOXA2 on inflammation, oxidative stress and apoptosis, as well as ERS in LPS-induced WI-38 cells were partly weakened by additional treatment with U46619. In conclusion, FOXA2 served a protective role against LPS-induced pneumonia by regulating p38/STAT3 signaling, providing a novel idea for the development of targeted therapeutic strategies for pneumonia.

PIAS1 upregulation confers protection against Cerulein-induced acute pancreatitis via FTO downregulation by enhancing sumoylation of Foxa2.

OBJECTIVE: This research discussed the specific mechanism by which PIAS1 affects acute pancreatitis (AP). METHODS: PIAS1, Foxa2, and FTO expression was assessed in Cerulein-induced AR42J cells and mice. Loss- and gain-of-function assays and Cerulein induction were conducted in AR42J cells and mice for analysis. The relationship among PIAS1, Foxa2, and FTO was tested. Cell experiments run in triplicate, and eight mice for each animal group. RESULTS: Cerulein-induced AP cells and mice had low PIAS1 and Foxa2 and high FTO. Cerulein induced pancreatic injury in mice and inflammation and oxidative stress in pancreatic tissues, which could be reversed by PIAS1 or Foxa2 upregulation or FTO downregulation. PIAS1 elevated SUMO modification of Foxa2 to repress FTO transcription. FTO upregulation neutralized the ameliorative effects of PIAS1 or Foxa2 upregulation on Cerulein-induced AR42J cell injury, inflammation, and oxidative stress. CONCLUSION: PIAS1 upregulation diminished FTO transcription by increasing Foxa2 SUMO modification, thereby ameliorating Cerulein-induced AP.

Forkhead box protein A2 alleviates toll-like receptor 4-mediated inflammation, endoplasmic reticulum stress, autophagy, and apoptosis induced by lipopolysaccharide in bovine hepatocytes.

Lipopolysaccharide (LPS) is an important stimulus of inflammation via binding to toll-like receptor 4 (TLR4), but the role of TLR4 in LPS-induced cellular homeostasis disruption indicated by the increased level of endoplasmic reticulum (ER) stress, autophagy, and apoptosis is unknown in the liver of dairy cows. Previous studies show that forkhead box protein A2 (FOXA2) is an important transcriptional factor to maintain cellular metabolic homeostasis, but the mechanisms by which FOXA2 mediates cellular homeostasis disruption in response to LPS remains unclear. To achieve the aims, hepatocytes separated from dairy cows at ∼160 d in milk were pretreated with a specific TLR4 inhibitor TAK-242 for 12 h, followed by LPS treatment for another 12 h to investigate the role of TLR4 in LPS-induced disruption of cellular homeostasis. The results indicated that LPS-induced nuclear factor-κB (NF-κB)-mediated inflammatory cascades, ER stress, autophagy, and apoptosis via activating TLR4 and downregulating FOXA2 expression in bovine hepatocytes. The application of TLR4 inhibitor alleviated LPS-induced inflammation through inactivating NF-κB proinflammatory pathway, restored cell homeostasis by decreasing the level of ER stress, autophagy, and apoptosis, and upregulated FOXA2 expression. Furthermore, we also elevated FOXA2 expression with an overexpression plasmid to clarify its molecular role in response to LPS challenge. FOXA2 overexpression reduced LPS-caused inflammation by inhibiting NF-κB signaling pathway. Also, FOXA2 could alleviate ER stress to block unfolded protein response and suppress autophagic flux. In addition, FOXA2 enhanced mitochondrial membrane potential via reducing pro-apoptotic protein BAX, CASPASE3, and Cleaved CASPASE3 expression and elevating anti-apoptotic protein BCL-2 expression to mitigate LPS-induced apoptosis. Taken together, these findings suggested that FOXA2 is a mediator to alleviate TLR4-controlled inflammation, ER stress, autophagy, and apoptosis in LPS-treated bovine hepatocytes, it could serve as a potential target to intervene cell homeostasis disruption caused by LPS in the liver of dairy cows.

A high-concentrate diet provokes inflammatory responses by downregulating Forkhead box protein A2 (FOXA2) through epigenetic modifications in the liver of dairy cows.

A high-concentrate diet has been reported to promote an inflammatory response in dairy cows. The purpose of this study was to clarify the effect of the high-concentrate (HC) diet on hepatic Forkhead box protein A2 (FOXA2) expression and uncover the molecular mechanisms in inflammatory responses in the liver. The results showed that the HC diet reduced the ruminal fluid pH and elevated the secretion of SAA3, IL-1α, and IL-8 and reduced that of IL-10 in peripheral blood plasma. Compared with the low-concentrate (LC) group, the concentration of myeloperoxidase (MPO) was higher in the liver of dairy cows in the HC group. In addition, the relative mRNA expression of acute phase proteins (HP, SAA3, and LBP), proinflammatory cytokines (TNFα, IL-1α, IL-1ß, IL-8), TLR4, MyD88, TRAF6, TRIF, IκBα, p65, p38 and JNK1 was upregulated and that of IL-10 was downregulated in the liver of the HC group. Consistently, the protein abundance of TLR4, TNFα and phosphorylation of proteins involved in NF-κB (IκBα and p65) and MAPK (p38 and JNK) pathways were significantly increased in the HC group compared with the LC group. And both the mRNA and protein abundance of FOXA2 were downregulated in the HC group. Further epigenetic analysis results demonstrated that chromatin compaction and DNA hypermethylation contributed to inhibiting FOXA2 expression, in which the demethylase ten-eleven translocation 1 (TET1) and histone deacetylase 3 (HDAC3) might participate. Overall, these findings demonstrated that the high-concentrate diet triggered inflammatory cascades and downregulated FOXA2 by epigenetic modifications in the liver of dairy cows.

Effect and potential molecular mechanism of FOXA2 on cell proliferation, migration and invasion of hepatocellular carcinoma / 中华肝胆外科杂志

Objective:To investigate the effect of forkhead box protein A2(FOXA2) on cell proliferation, migration and invasion of hepatocellular carcinoma and the potential molecular mechanism.Methods:From January 2019 to December 2020, 10 cases of hepatocellular carcinoma patients from Zhongnan Hospital of Wuhan University were collected for study, including 7 males and 3 females, with an average age of 53 years. FOXA2 expression was detected in human liver cancer cell line, and the highest expression of FOXA2 was found in HepG2 cells transfected with FOXA2 overexpression plasmid. Immunohistochemistry and qRT-PCR were used to detect the expression of FOXA2. Western blot was used to detect the expression of FOXA2, hypoxia-inducible factor-1 α (HIF-1α), vascular endothelial growth factor A (VEGFA), B-cell lymphofactor-2 (Bcl-2), matrix metalloproteinase (MMP) 7, and glucose transporter (GLUT) 1. EdU assay was used to study cell proliferation, and Transwell chamber assay was used to study cell migration and invasion.Results:The relative expression of FOXA2 in liver cancer tissues were lower than those in adjacent tissues both at mRNA and protein levels, with statistical significance (both P<0.05). FOXA2 overexpression group showed lower cell proliferation rate (30.0±3.2)%, migration rate (10.6±1.1), and invasion rate (12.8±0.8) comparing with negative control group (67.0±3.6)%, (81.0±5.4), (74.8±4.5). The difference was statistically significant (all P<0.05). Expression of HIF-1α and its downstream targets VEGFA, MMP7, GLUT1 and Bcl-2 was decreased after over-expression of FOXA2 in HepG2 cells. Conclusion:FOXA2 inhibits proliferation, migration, and invasion in hepatocellular carcinoma by regulating HIF-1α signaling pathway, suggesting that FOXA2 is a potential target for the treatment of hepatocellular carcinoma.

Knockdown of FOXA2 Impairs Hair-Inductive Activity of Cultured Human Follicular Keratinocytes.

Reciprocal interactions between hair-inductive dermal cells and epidermal cells are essential for de novo genesis of hair follicles. Recent studies have shown that outer root sheath (ORS) follicular keratinocytes can be expanded in vitro, but the cultured cells often lose receptivity to hair-inducing dermal signals. In this study, we first investigated whether the hair-inductive activity (trichogenicity) of cultured human ORS follicular keratinocytes was correlated with the cultivation period. ORS follicular keratinocytes from the scalp were cultured for 3, 4, 5, or 6 weeks and were then implanted into nude mice along with freshly isolated neonatal mouse dermal cells. We observed that the trichogenicity of the implanted ORS cells was inversely correlated with their cultivation period. These initial findings prompted us to investigate the differentially expressed genes between the short-term (20 days) and long-term (42 days) cultured ORS cells, trichogenic and non-trichogenic, respectively, by microarray analysis. We found that forkhead box protein A2 (FOXA2) was the most up-regulated transcription factor in the trichogenic ORS cells. Thus, we investigated whether the trichogenicity of the cells was affected by FOXA2 expression. We found a significant decrease in the number of induced hair follicles when the ORS cells were transfected with a FOXA2 small interfering RNA versus control small interfering RNA. Taken together, our data strongly suggest that FOXA2 significantly influences the trichogenicity of human ORS cells.

Angiopoietin-1 accelerates Alzheimer's disease via FOXA2/PEN2/APP pathway in APP/PS1 mice.

Angiopoietin-1 (Ang-1), a regulatory angiogenesis protein and it has been found to be involved in the occurrence and progression of Alzheimer's disease. However, it was still to be addressed the distinctly role and the molecular mechanisms of Ang-1 affects Alzheimer's disease. Our data suggest that Ang-1 aggravated the accumulation of Aß42 and cognitive decline in APP/PS1 mice. The upregulation of APPß is essential for Aß42 production in N2a cells overexpressing the mutational human APP gene (N2a/APP695 cells), while downregulation of PEN2 could reduce APP expression. Silencing of FOXA2 lead to inhibition of APP expression, as well as decrease of Aß42 contents. In conclusion, Ang-1 has an accelerative effect on Alzheimer's disease by increasing the secretion of Aß42 via FOXA2/PEN2/APP pathway.

Changes in EGFR, FOXA2 and MUC5AC expression in respiratory syncytial virus-infected human bronchial epithelium cells and effects of rosiglitazone intervention / 中华微生物学和免疫学杂志

Objective To investigate the mechanism of epidermal growth factor receptor-forkhead transcription factor A2 (EGFR-FOXA2) pathway-involved high secretion of mucus in human bronchial epitheli-um (HBE) cells after respiratory syncytial virus (RSV) infection and to evaluate the effects of intervention using agonist ( rosiglitazone ) and antagonist ( GW9662 ) of peroxidase proliferation activated receptor γ( PPARγ) and EGFR inhibitor ( AG1478 ) . Methods HBE cells were randomly divided into six groups: A group ( AG1478+RSV) , B group ( rosiglitazone+RSV) , C group ( GW9662+RSV) , D group ( RSV) , E group (0. 1％ dimethyl sulfoxide DMSO) and F group (HBE cell control group). Two hours before RSV infection, A, B and C groups were respectively treated with 10 μmol/L of AG1478, rosiglitazone and GW9662. Expression of EGFR, PPARγ and FOXA2 at mRNA level in each group was detected by real-time fluorescence quantitative RT-PCR 12 h, 24 h and 48 h after HBE cells were infected with or without RSV. Expression of phosphorylated-EGFR ( p-EGFR) and EGFR at protein level was detected by Western blot. ELISA was performed to measure the expression of mucin-5AC (MUC5AC). Results Compared with F group, EGFR expression at mRNA lev-el, p-EGFR/EGFR protein ratio and MUC5AC expression at protein level were increased in a time-dependent manner in A, B, C and D groups at 12 h, 24 h and 48 h. Compared with group F, the expression of PPARγat mRNA level in A, B, and D groups increased at each time point. Moreover, PPARγ expression gradually in-creased over time in A and B groups, reaching the peaks at 48 h, but was in decline in D group. Expression of FOXA2 at mRNA level in RSV-infected HBE cells was declined at each time point compared with that in group F, especially in D group. Compared with group D, A and B groups showed significantly decreased EGFR ex-pression at mRNA level, p-EGFR/EGFR protein ratio and MUC5AC expression at protein level, but markedly increased FOXA2 expression at mRNA level. Conclusions RSV infection increased the expression of MUC5AC at protein level in HBE cells. PPARγand EGFR-FOXA2 signaling pathways were involved in the hypersecretion of airway mucus during RSV infection.

Forkhead box protein A2 and T helper type 2-mediated pulmonary inflammation.

The transcription factor forkhead box protein A2 (FOXA2, also known as hepatocyte nuclear factor 3ß or transcription factor 3ß), has been found to play pivotal roles in multiple phases of mammalian life, from the early development to the organofaction, and subsequently in homeostasis and metabolism in the adult. In the embryonic development period, FOXA2 is require d for the formation of the primitive node and notochord, and its absence results in embryonic lethality. Moreover, FOXA2 plays an important role not only in lung development, but also in T helper type 2 (Th2)-mediated pulmonary inflammation and goblet cell hyperplasia. In this article, the role of FOXA2 in lung development and Th2-mediated pulmonary inflammation, as well as in goblet cell hyperplasia, is reviewed. FOXA2 deletion in airway epithelium results into Th2-mediated pulmonary inflammation and goblet cell hyperplasia in developing lung. Leukotriene pathway and signal transducers and activators of transcription 6 pathway may mediate this inflammation through recruitment and activation of denditric cell during lung developments. FOXA2 is a potential treatment target for lung diseases with Th2 inflammation and goblet cell hyperplasia, such as asthma and chronic obstructive pulmonary disease.

Lipid-rich diet enhances L-cell density in obese subjects and in mice through improved L-cell differentiation.

The enterohormone glucagon-like peptide-1 (GLP-1) is required to amplify glucose-induced insulin secretion that facilitates peripheral glucose utilisation. Alteration in GLP-1 secretion during obesity has been reported but is still controversial. Due to the high adaptability of intestinal cells to environmental changes, we hypothesised that the density of GLP-1-producing cells could be modified by nutritional factors to prevent the deterioration of metabolic condition in obesity. We quantified L-cell density in jejunum samples collected during Roux-en-Y gastric bypass in forty-nine severely obese subjects analysed according to their fat consumption. In mice, we deciphered the mechanisms by which a high-fat diet (HFD) makes an impact on enteroendocrine cell density and function. L-cell density in the jejunum was higher in obese subjects consuming >30 % fat compared with low fat eaters. Mice fed a HFD for 8 weeks displayed an increase in GLP-1-positive cells in the jejunum and colon accordingly to GLP-1 secretion. The regulation by the HFD appears specific to GLP-1-producing cells, as the number of PYY (peptide YY)-positive cells remained unchanged. Moreover, genetically obese ob/ob mice did not show alteration of GLP-1-positive cell density in the jejunum or colon, suggesting that obesity per se is not sufficient to trigger the mechanism. The higher L-cell density in HFD-fed mice involved a rise in L-cell terminal differentiation as witnessed by the increased expression of transcription factors downstream of neurogenin3 (Ngn3). We suggest that the observed increase in GLP-1-positive cell density triggered by high fat consumption in humans and mice might favour insulin secretion and therefore constitute an adaptive response of the intestine to balance diet-induced insulin resistance.