Mapping out p38MAPK

Melatonin changes energy metabolism and reduces oncogenic signaling in ovarian cancer cells

Ovarian cancer (OC) adjusts energy metabolism in favor of its progression and dissemination. Because melatonin (Mel) has antitumor actions, we investigated its impact on energy metabolism and kinase signaling in OC cells (SKOV-3 and CAISMOV-24). Cells were divided into control and Mel-treated groups, in the presence or absence of the antagonist luzindole. There was a decrease in the levels of HIF-1α, G6PDH, GAPDH, PDH, and CS after Mel treatment even in the presence of luzindole in both OC cells. Mel treatment also reduced the activity of OC-related enzymes including PFK-1, G6PDH, LDH, CS, and GS whereas PDH activity was increased. Lactate and glutamine levels dropped after Mel treatment. Mel further promoted a reduction in the concentrations of CREB, JNK, NF-kB, p-38, ERK1/2, AKT, P70S6K, and STAT in both cell lines. Mel reverses Warburg-type metabolism and possibly reduces glutaminolysis, thereby attenuating various oncogenic molecules associated with OC progression and invasion.

Metabolomics of human umbilical vein endothelial cell-based analysis of the relationship between hyperuricemia and dyslipidemia

BACKGROUND AND AIMS

Hyperuricemia frequently accompanies dyslipidemia, yet the precise mechanism remains elusive. Leveraging cellular metabolomics analyses, this research probes the potential mechanisms wherein hyperuricemia provokes endothelial cell abnormalities, inducing disordered bile metabolism and resultant lipid anomalies.

METHODS AND RESULTS

We aimed to identify the differential metabolite associated with lipid metabolism through adopting metabolomics approach, and thereafter adequately validating its protective function on HUVECs by using diverse assays to measure cellular viability, reactive oxygen species, migration potential, apoptosis and gene and protein levels of inflammatory factors. Taurochenodeoxycholic acid (TCDCA) (the differential metabolite of HUVECs) and the TCDCA-involved primary bile acid synthesis pathway were found to be negatively correlated with high UA levels based on the results of metabolomics analysis. It was noted that compared to the outcomes observed in UA-treated HUVECs, TCDCA could protect against UA-induced cellular damage and oxidative stress, increase proliferation as well as migration, and decreases apoptosis. In addition, it was observed that TCDCA might protect HUVECs by inhibiting UA-induced p38 mitogen-activated protein kinase/nuclear factor kappa-B p65 (p38MAPK/NF-κB p65) pathway gene and protein levels, as well as the levels of downstream inflammatory factors.

CONCLUSION

The pathogenesis of hyperuricemia accompanying dyslipidemia may involve high uric acid levels eliciting inflammatory reactions and cellular damage in human umbilical vein endothelial cells (HUVECs), mediated through the p38MAPK/NF-κB signaling pathway, subsequently impinging on cellular bile acid synthesis and reducing bile acid production.

Genetic associations in ankylosing spondylitis: circulating proteins as drug targets and biomarkers

Background

Ankylosing spondylitis (AS) is a complex condition with a significant genetic component. This study explored circulating proteins as potential genetic drug targets or biomarkers to prevent AS, addressing the need for innovative and safe treatments.

Methods

We analyzed extensive data from protein quantitative trait loci (pQTLs) with up to 1,949 instrumental variables (IVs) and selected the top single-nucleotide polymorphism (SNP) associated with AS risk. Utilizing a two-sample Mendelian randomization (MR) approach, we assessed the causal relationships between identified proteins and AS risk. Colocalization analysis, functional enrichment, and construction of protein-protein interaction networks further supported these findings. We utilized phenome-wide MR (phenMR) analysis for broader validation and repurposing of drugs targeting these proteins. The Drug-Gene Interaction database (DGIdb) was employed to corroborate drug associations with potential therapeutic targets. Additionally, molecular docking (MD) techniques were applied to evaluate the interaction between target protein and four potential AS drugs identified from the DGIdb.

Results

Our analysis identified 1,654 plasma proteins linked to AS, with 868 up-regulated and 786 down-regulated. 18 proteins (AGER, AIF1, ATF6B, C4A, CFB, CLIC1, COL11A2, ERAP1, HLA-DQA2, HSPA1L, IL23R, LILRB3, MAPK14, MICA, MICB, MPIG6B, TNXB, and VARS1) that show promise as therapeutic targets for AS or biomarkers, especially MAPK14, supported by evidence of colocalization. PhenMR analysis linked these proteins to AS and other diseases, while DGIdb analysis identified potential drugs related to MAPK14. MD analysis indicated strong binding affinities between MAPK14 and four potential AS drugs, suggesting effective target-drug interactions.

Conclusion

This study underscores the utility of MR analysis in AS research for identifying biomarkers and therapeutic drug targets. The involvement of Th17 cell differentiation-related proteins in AS pathogenesis is particularly notable. Clinical validation and further investigation are essential for future applications.

Absent in melanoma 2 attenuates proliferation and migration and promotes apoptosis of human colorectal cancer cells by activating P38MAPK signaling pathway

Colorectal cancer (CRC) stands among the top prevalent cancers worldwide and holds a prominent position as a major contributor to cancer-related mortality globally. Absent in melanoma 2 (AIM2), a constituent of the interferon-inducible hematopoietic interferon-inducible nuclear antigens with 200 amino acid repeats protein family, contributes to both cancer progression and inflammasome activation. Despite this understanding, the precise biological functions and molecular mechanisms governed by AIM2 in CRC remain elusive. Consequently, this study endeavors to assess AIM2's expression levels, explore its potential antitumor effects, elucidate associated cancer-related processes, and decipher the underlying signaling pathways in CRC. Our findings showed a reduced AIM2 expression in most CRC cell lines. Elevation of AIM2 levels suppressed CRC cell proliferation and migration, altered cell cycle by inhibiting G1/S transition, and induced cell apoptosis. Further research uncovered the participation of P38 mitogen-activated protein kinase (P38MAPK) in AIM2-mediated modulation of CRC cell apoptosis and proliferation. Altogether, our achievements distinctly underscored AIM2's antitumor role in CRC. AIM2 overexpression inhibited proliferation and migration and induced apoptosis of CRC cells via activating P38MAPK signaling pathway, indicating AIM2 as a prospective and novel therapeutic target for CRC.

Critical roles of PU.1/cathepsin S activation in regulating inflammatory responses of macrophages in periodontitis

OBJECTIVE

To determine the critical roles of PU.1/cathepsin S activation in regulating inflammatory responses of macrophages during periodontitis.

BACKGROUND

Cathepsin S (CatS) is a cysteine protease and exerts important roles in the immune response. Elevated CatS has been found in the gingival tissues of periodontitis patients and is involved in alveolar bone destruction. However, the underlying mechanism of CatS-driven IL-6 production in periodontitis remains unclear.

METHODS

Western blot was applied to measure mature cathepsin S(mCatS) and IL-6 expression in gingival tissues from periodontitis patients and RAW264.7 cells exposed to lipopolysaccharide from Porphyromonas gingivalis (P.g. LPS). Immunofluorescence was applied to confirm the localization of PU.1, and CatS in the gingival tissues of periodontitis patients. ELISA was performed to determine IL-6 production by the P.g. LPS-exposed RAW264.7 cells. Knockdown by shRNA was used to determine the effects of PU.1 on p38/ nuclear factor (NF)-κB activation, mCatS expression and IL-6 production in RAW264.7 cells.

RESULTS

The expressions mCatS and IL-6 were significantly upregulated in gingival macrophages. In cultured RAW264.7 cells, increased mCatS and IL-6 protein paralleled the activation of p38 and NF-κB after exposure to P.g. LPS. CatS knockdown by shRNA significantly decreased P.g. LPS-induced IL-6 expression and p38/NF-κB activation. PU.1 was significantly increased in P.g. LPS-exposed RAW264.7 cells, and PU.1 knockdown dramatically abolished the P.g. LPS-induced upregulation of mCatS and IL-6 and the activation of p38 and NF-κB. Furthermore, PU.1 and CatS colocalized in macrophages within the gingival tissues of periodontitis patients.

CONCLUSION

PU.1-dependent CatS drives IL-6 production in macrophages by activating p38 and NF-κB in periodontitis.

Involvement of the p38/MK2 Pathway in MCLR Hepatotoxicity Revealed through MAPK Pharmacological Inhibition and Phosphoproteomics in HepaRG Cells

Microcystin-leucine arginine (MCLR) is one of the most common and toxic microcystin variants, a class of cyanotoxins produced by cyanobacteria. A major molecular mechanism for MCLR-elicited liver toxicity involves the dysregulation of protein phosphorylation through protein phosphatase (PP) inhibition and mitogen-activated protein kinase (MAPK) modulation. In this study, specific pharmacological MAPK inhibitors were used in HepaRG cells to examine the pathways associated with MCLR cytotoxicity. SB203580 (SB), a p38 inhibitor, rescued HepaRG cell viability, whereas treatment with SP600125 (JNK inhibitor), MK2206 (AKT inhibitor), or N-acetylcysteine (reactive oxygen species scavenger) did not. Phosphoproteomic analysis revealed that phosphosites-which were altered by the addition of SB compared to MCLR treatment alone-included proteins involved in RNA processing, cytoskeletal stability, DNA damage response, protein degradation, and cell death. A closer analysis of specific proteins in some of these pathways indicated that SB reversed the MCLR-mediated phosphorylation of the necroptosis-associated proteins, the mixed lineage kinase domain-like protein (MLKL), receptor-interacting serine/threonine kinase 1 (RIP1), DNA damage response proteins, ataxia telangiectasia and Rad3-related kinase (ATR), and checkpoint kinase 1 (CHK1). Overall, these data implicate p38/MK2, DNA damage, and necroptosis in MCLR-mediated hepatotoxicity, and suggest these pathways may be targets for prevention prior to, or treatment after, MCLR toxicity.

Effects and Mechanisms of Kaempferol in the Management of Cancers through Modulation of Inflammation and Signal Transduction Pathways

Cancer is the principal cause of death and its incidence is increasing continuously worldwide. Various treatment approaches are in practice to treat cancer, but these treatment strategies may be associated with severe side effects and also produce drug resistance. However, natural compounds have established their role in cancer management with minimal side effects. In this vista, kaempferol, a natural polyphenol, mainly found in vegetables and fruits, has been revealed to have many health-promoting effects. Besides its health-promoting potential, its anti-cancer potential has also been described in in vivo as well as in in vitro studies. The anti-cancer potential of kaempferol has been proven through modulation of cell signaling pathways in addition to the induction of apoptosis and cell cycle arrest in cancer cells. It leads to the activation of tumor suppressor genes, inhibition of angiogenesis, PI3K/AKT pathways, STAT3, transcription factor AP-1, Nrf2 and other cell signaling molecules. Poor bioavailability of this compound is one of the major limitations for its proper and effective disease management actions. Recently, some novel nanoparticle-based formulations have been used to overcome these limitations. The aim of this review is to provide a clear picture regarding the mechanism of action of kaempferol in different cancers through the modulation of cell signaling molecules. Besides this, strategies to improve the efficacy and synergistic effects of this compound have also been described. However, more studies are needed based on clinical trials to fully explore the therapeutic role of this compound, especially in cancer treatment.

FGFR inhibitors combined with nab-paclitaxel - A promising strategy to treat non-small cell lung cancer and overcome resistance

Lung cancer has high morbidity and mortality rates worldwide, and NSCLC accounts for 85% of all lung cancer cases. Despite the development of targeted therapies and immunotherapy, many NSCLC patients do not effectively respond to treatment, and new treatment strategies are urgently needed. Aberrant activation of the FGFR signaling pathway is closely related to the initiation and progression of tumors. AZD4547, which is a selective inhibitor of FGFR 1-3, can suppress the growth of tumor cells with deregulated FGFR expression in vivo and in vitro. However, further exploration is needed to determine whether AZD4547 can play an antiproliferative role in tumor cells without deregulated FGFR expression. We investigated the antiproliferative effect of AZD4547 on NSCLC cells without deregulated FGFR expression. In vivo and in vitro experiments showed that AZD4547 exerted a weak antiproliferative effect on NSCLC cells without deregulated FGFR expression, but it significantly enhanced the sensitivity of NSCLC cells to nab-paclitaxel. We found that AZD4547 combined with nab-paclitaxel suppressed the phosphorylation of the MAPK signaling pathway, led to cell cycle arrest in the G2/M phase, promoted apoptosis, and inhibited cell proliferation more substantially than nab-paclitaxel alone. These findings provide insight into the rational use of FGFR inhibitors and personalized treatment of NSCLC patients.

P38 Mediates Tumor Suppression through Reduced Autophagy and Actin Cytoskeleton Changes in NRAS-Mutant Melanoma

Hotspot mutations in the NRAS gene are causative genetic events associated with the development of melanoma. Currently, there are no FDA-approved drugs directly targeting NRAS mutations. Previously, we showed that p38 acts as a tumor suppressor in vitro and in vivo with respect to NRAS-mutant melanoma. We observed that because of p38 activation through treatment with the protein synthesis inhibitor, anisomycin leads to a transient upregulation of several targets of the cAMP pathway, representing a stressed cancer cell state that is often observed by therapeutic doses of MAPK inhibitors in melanoma patients. Meanwhile, genetically induced p38 or its stable transduction leads to a distinct cellular transcriptional state. Contrary to previous work showing an association of invasiveness with high p38 levels in BRAF-mutated melanoma, there was no correlation of p38 expression with NRAS-mutant melanoma invasion, highlighting the difference in BRAF and NRAS-driven melanomas. Although the role of p38 has been reported to be that of both tumor suppressor and oncogene, we show here that p38 specifically plays the role of a tumor suppressor in NRAS-mutant melanoma. Both the transient and stable activation of p38 elicits phosphorylation of mTOR, reported to be a master switch in regulating autophagy. Indeed, we observed a correlation between elevated levels of phosphorylated mTOR and a reduction in LC3 conversion (LCII/LCI), indicative of suppressed autophagy. Furthermore, a reduction in actin intensity in p38-high cells strongly suggests a role of mTOR in regulating actin and a remodeling in the NRAS-mutant melanoma cells. Therefore, p38 plays a tumor suppressive role in NRAS-mutant melanomas at least partially through the mechanism of mTOR upregulation, suppressed autophagy, and reduced actin polymerization. One or more combinations of MEK inhibitors with either anisomycin, rapamycin, chloroquine/bafilomycin, and cytochalasin modulate p38 activation, mTOR phosphorylation, autophagy, and actin polymerization, respectively, and they may provide an alternate route to targeting NRAS-mutant melanoma.

2, 2', 4, 4'-tetrabromodiphenyl ether induces placental toxicity via activation of p38 MAPK signaling pathway in vivo and in vitro

2, 2', 4, 4'-tetrabromodiphenyl ether (BDE-47) is one of the most important polybrominated diphenyl ethers (PBDEs) congeners, and epidemiological studies have shown that it can cause adverse pregnancy outcomes. The aim of our study was to investigate the role of placental injury in BDE-47-induced adverse pregnancy outcomes through in vivo and in vitro models. From day 0.5 to day 16.5 of pregnancy of ICR mice, BDE-47 oral doses of 0, 25, 50 and 100 mg/kg/day were administered. Immunohistochemical staining found that BDE-47 inhibited the expression of CD34 in mouse placenta, and ELISA results showed that BDE-47 reduced the levels of VEGF and PlGF in the serum of pregnant mice. Western blot assays found that the expression levels of VEGF-A and invasion-related factors were decreased in the placentas of BDE-47-treated group, which indicated that BDE-47 could impair placental angiogenesis. Furthermore, BDE-47 inhibited proliferation, increased apoptosis and autophagy, and activated p38 MAPK signaling pathway in mouse placental tissue. In vitro, HTR-8/SVneo cells were treated with 0, 5, 10, 20 μM BDE-47 for 24 h. Wound healing assays and Transwell assays showed that BDE-47 inhibited the migration and invasion ability of HTR-8/SVneo cells. We also found that BDE-47 inhibited the proliferation of HTR-8/SVneo cells and increased apoptosis and autophagy. BDE-47 activated p38 MAPK signaling pathway in HTR-8/SVneo cells, and inhibition of p38 MAPK signaling pathway in HTR-8/SVneo cells restored the effects caused by BDE-47. In conclusion, BDE-47 impairs placental angiogenesis by inhibiting cell migration and invasion, and induces placental toxicity by inhibiting proliferation, increasing apoptosis and autophagy. In vitro, activation of p38 MAPK signaling pathway is involved in the processes of placental injury by BDE-47.

Proteome Analysis of Swine Macrophages after Infection with Two Genotype II African Swine Fever Isolates of Different Pathogenicity

Since the introduction of a highly pathogenic genotype II isolate of the African swine fever virus (ASFV) into Georgia in 2007, African swine fever (ASF) has gone panzootic. Outbreaks have been reported in Europe, Asia and, more recently, Latin America. Thus, ASFV has become a major threat to the pig industry worldwide, as broadly applicable vaccines are not available. While the majority of ASFV strains show high virulence in domestic pigs and wild boar, variations within the ASFV genome have resulted in the emergence of attenuated strains with low or moderate virulence. However, the molecular basis of the differences in virulence has not yet been discovered. To reveal virulence-associated protein expression patterns, we analysed the proteomes of the natural target cells of ASFV, primary porcine macrophages, after infection with two genotype II ASFV strains displaying high (Armenia 2008) and moderate (Estonia 2014) virulence using quantitative mass spectrometry. Very similar expression patterns were observed for the viral genes, and any differences were limited to the deletions within the Estonia 2014 genome. In addition to the canonical ASFV proteins, twelve novel protein products from recently described transcripts were confirmed in both isolates. Pathway analyses showed that both isolates evoked a similar host proteome response, despite their difference in virulence. However, subtle differences in the manipulation of the proteins involved in the proinflammatory response mediated by the MAPK14/p38 signalling cascade were observed.

Reactive oxygen species-dependent-NLRP3 inflammasome activation in human neutrophils induced by l-amino acid oxidase derived from Calloselasma rhodostoma venom

l-Amino acid oxidase isolated from Calloselasma rhodostoma (Cr-LAAO) snake venom is a potent stimulus for neutrophil activation and production of inflammatory mediators, contributing to local inflammatory effects in victims of envenoming. Cr-LAAO triggered the activation of nicotinamide adenine dinucleotide phosphatase (NADPH) oxidase complex and protein kinase C (PKC)-α signaling protein for reactive oxygen species (ROS) production. This study aims to evaluate the ROS participation in the NLRP3 inflammasome complex activation in human neutrophil. Human neutrophils were isolated and stimulated for 1 or 2 h with RPMI (negative control), LPS (1 μg/mL, positive control) or Cr-LAAO (50 μg/mL). The neutrophil transcriptome was examined using the microarray technique, and RT-qPCR for confirmation of gene expression. Immunofluorescence assays for NLRP3, caspase-1, IL-1β and GSDMD proteins was performed by Western blot in the presence and/or absence of Apocynin, an inhibitor of NADPH oxidase. IL-1β release was also detected in the presence and/or absence of NLRP3, caspase-1 and NADPH oxidase inhibitors. Results showed that Cr-LAAO upregulated the expression of genes that participate in the NADPH oxidase complex formation and inflammasome assembly. NLRP3 was activated and accumulated in the cytosol forming punctas, indicating its activation. Gasdermin D was not cleaved but lactate dehydrogenase was released. Furthermore, ROS inhibition decreased the expression of NLRP3 inflammasome complex proteins, as observed by protein expression in the presence and/or absence of apocynin, an NADPH oxidase inhibitor. IL-1β was also released, and pharmacological inhibition of NLRP3, caspase-1, and ROS reduced the amount of released cytokine. This is the first report demonstrating the activation of the NLRP3 inflammasome complex via ROS generation by Cr-LAAO, which may lead to the development of local inflammatory effects observed in snakebite victims.

Tiao-bu-fei-shen formula promotes downregulation of the caveolin 1-p38 mapk signaling pathway in COPD - Associated tracheobronchomalacia cell model

ETHNOPHARMACOLOGICAL RELEVANCE

The Tiao-bu-fei-shen (TBFS) formula, extensively used in Traditional Chinese Medicine (TCM), can enhance therapeutic efficacy and reduce the frequency of acute exacerbations of lung-kidney Qi deficiency in patients with chronic obstructive pulmonary disease (COPD). According to both TCM theory and long-term observation of practice, TBFS has become an effective treatment for COPD-associated tracheobronchomalacia (TBM).

AIM OF THE STUDY

To investigate the mechanism of the TBFS formula in treating COPD-associated TBM based on caveolin 1-p38 MAPK signaling and apoptosis.

MATERIALS AND METHODS

A rat COPD model was prepared by exposure to smoking combined with tracheal lipopolysaccharide injection. The trachea or bronchus chondrocytes from COPD rats were isolated, cultured, and treated with 10 ng/mL IL-1β for 24 h to develop a model of COPD-associated TBM. Normal rats were administered TBFS to prepare drug-containing serum, and CCK8 assays were used to screen the optimal drug-containing serum concentration and SB203580 dose. TBFS drug-containing serum and SB203580 were processed separately for the control, model, drug-containing serum, blocker, and drug-containing serum combined with blocker groups. Flow cytometry and CCK8 assays were used to detect apoptosis and proliferative activity. Toluidine blue staining and immunohistochemistry were used to analyze the chondrocyte proteoglycan and type II collagen content. Western blotting was used to detect the expression of caveolin 1, p-p38 MAPK, TNF-α, IL-1β, MMP-13, Bax, and Bcl-2 proteins. Quantitative PCR was used to detect the expression of caveolin 1, p38 MAPK, IL-1β, MMP-13, Bax, Bcl-2, and miR-140-5p.

RESULTS

The isolation and identification of bronchial chondrocytes from COPD rats revealed that 10 ng/mL IL-1β can produce a stable COPD-associated TBM model. Screened via the CCK8 method, fourth-generation bronchial chondrocytes were determined as the optimal cells, and 5 μM SB203580 and 5% low-dose drug-containing serum were the optimal intervention doses. The experimental chondrocytes of each group were treated separately for 48 h. Toluidine blue staining and immunohistochemical analysis revealed that TBFS drug-containing serum, SB203580, and TBFS drug-containing serum combined with SB203580 can effectively increase the proteoglycan and type II collagen content after chondrocyte degradation. Flow cytometry of cells treated with SB203580 and TBFS drug-containing serum combined with SB203580 revealed significantly reduced cell apoptosis and enhanced cell proliferation activity. Western blot and qPCR analyses revealed that the TBFS drug-containing serum, SB203580, and TBFS drug-containing serum combined with SB203580 effectively inhibit the expression of caveolin 1, p-p38 MAPK, MMP-13, IL-1β, TNF-α, and Bax proteins while promoting Bcl -2 protein expression. Treatment with TBFS drug-containing serum and SB203580 effectively inhibited the expression of MMP-13, p38 MAPK, caveolin 1, and Bax genes, and promoted the expression of Bcl-2 and miR-140-5p genes.

CONCLUSIONS

A concentration of 10 ng/mL of IL-1β can generate a stable COPD-associated TBM cell model. TBFS can improve the proteoglycan and type II collagen content, increase cell activity, and reduce the amount of chondrocyte apoptosis. The role of TBFS may be related to mechanisms of inhibiting the expression of the key signaling molecules caveolin 1 and p-p38 MAPK in the caveolin 1-p38 MAPK signaling pathway, thereby reducing the expression of the downstream effector products MMP-13, IL-1β, and TNF-α, while inhibiting the expression of the apoptotic gene Bax and improving the expression of Bcl-2 and miR-140-5p genes.

DAPK1 Interacts with the p38 isoform MAPK14, Preventing its Nuclear Translocation and Stimulation of Bone Marrow Adipogenesis

Bone marrow (BM) adipose tissue (BMAT), a unique adipose depot, plays an important role in diseases such as osteoporosis and bone metastasis. Precise control of mesenchymal stem cell (MSC) differentiation is critical for BMAT formation and regeneration. Here, we show that death associated protein kinase 1 (DAPK1) negatively regulates BM adipogenesis in vitro and in vivo. Prx1 creDapk1 loxp/loxp mice showed more adipocytes in the femur than Dapk1 loxp/loxp mice. Further mechanistic analyses revealed that DAPK1 inhibits p38 mitogen-activated protein kinase (MAPK) signaling in the nucleus by binding the p38 isoform MAPK14, decreasing p38 nuclear activity, which subsequently inhibits BM adipogenesis. The inhibitory effect of DAPK1 against MAPK14 was independent of its kinase activity. In addition, the decreased DAPK1 was observed in the BM-MSCs of ageing mice. Our results reveal a previously undescribed function for DAPK1 in the regulation of adipogenesis, and may also reveal the underlying mechanism of BMAT formation in ageing.

Identification of Novel Kinase-Transcription Factor-mRNA-miRNA Regulatory Network in Nasopharyngeal Carcinoma by Bioinformatics Analysis

Purpose

Nasopharyngeal carcinoma (NPC) is one of the most common malignant tumors of the head and neck. This study aimed to investigate the crucial genes and regulatory networks involved in the carcinogenesis of NPC using a bioinformatics approach.

Methods

Five mRNA and two miRNA expression datasets were downloaded from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) and miRNAs (DEMs) between NPC and normal samples were analyzed using R software. The WebGestalt tool was used for functional enrichment analysis, and protein-protein interaction (PPI) network analysis of DEGs was performed using STRING database. Transcription factors (TFs) were predicted using TRRUST and Transcriptional Regulatory Element Database (TRED). Kinases were identified using X2Kgui. The miRNAs of DEGs were predicted using miRWalk database. A kinase-TF-mRNA-miRNA integrated network was constructed, and hub nodes were selected. The hub genes were validated using NPC datasets from the GEO and Oncomine databases. Finally, candidate small-molecule agents were predicted using CMap.

Results

A total of 122 DEGs and 44 DEMs were identified. DEGs were associated with the immune response, leukocyte activation, endoplasmic reticulum stress in GO analysis, and the NF-κB signaling pathway in KEGG analysis. Four significant modules were identified using PPI network analysis. Subsequently, 26 TFs, 73 kinases, and 2499 miRNAs were predicted. The predicted miRNAs were cross-referenced with DEMs, and seven overlapping miRNAs were selected. In the kinase-TF-mRNA-miRNA integrated network, eight genes (PTGS2, FN1, MMP1, PLAU, MMP3, CD19, BMP2, and PIGR) were identified as hub genes. Hub genes were validated with consistent results, indicating the reliability of our findings. Finally, six candidate small-molecule agents (phenoxybenzamine, luteolin, thioguanosine, reserpine, blebbistatin, and camptothecin) were predicted.

Conclusion

We identified DEGs and an NPC regulatory network involving kinases, TFs, mRNAs, and miRNAs, which might provide promising insight into the pathogenesis, treatment, and prognosis of NPC.

RPL35A is a key promotor involved in the development and progression of gastric cancer

BACKGROUND

RPL35A has been reported to work as a biomarker in tumor angiogenesis. However, little work has been performed on the expression level and functional importance of RPL35A in gastric cancer (GC).

METHODS

The protein expression level of RPL35A was detected by immunohistochemical staining and western blot analysis. The Celigo cell counting assay was used to assess cell proliferation. Both the wound healing assay and the transwell assay were conducted to evaluate cell migration. Flow cytometric analysis was utilized to detect cell apoptosis and cell cycle. A mouse xenograft model was constructed for in vivo experiments.

RESULTS

The results demonstrated that RPL35A expression was abundantly up-regulated in GC and positively related to tumor infiltrate. In addition, RPL35A knockdown could significantly suppress cell proliferation, migration, enhance apoptosis and arrest cell cycle. The in vivo study also verified the inhibitory effects of RPL35A knockdown on GC tumorigenesis.

CONCLUSIONS

The above mentioned results indicated that the knockdown of RPL35A might be a considerable therapeutic strategy for the treatment of gastric cancer.

The Role of Bacterial Proteases in Microbe and Host-microbe Interactions

BACKGROUND

Secreted proteases are an important class of factors used by bacterial to modulate their extracellular environment through the cleavage of peptides and proteins. These proteases can range from broad, general proteolytic activity to high degrees of substrate specificity. They are often involved in interactions between bacteria and other species, even across kingdoms, allowing bacteria to survive and compete within their niche. As a result, many bacterial proteases are of clinical importance. The immune system is a common target for these enzymes, and bacteria have evolved ways to use these proteases to alter immune responses for their benefit. In addition to the wide variety of human proteins that can be targeted by bacterial proteases, bacteria also use these secreted factors to disrupt competing microbes, ranging from outright antimicrobial activity to disrupting processes like biofilm formation.

OBJECTIVE

In this review, we address how bacterial proteases modulate host mechanisms of protection from infection and injury, including immune factors and cell barriers. We also discuss the contributions of bacterial proteases to microbe-microbe interactions, including antimicrobial and anti-biofilm dynamics.

CONCLUSION

Bacterial secreted proteases represent an incredibly diverse group of factors that bacteria use to shape and thrive in their microenvironment. Due to the range of activities and targets of these proteases, some have been noted for having potential as therapeutics. The vast array of bacterial proteases and their targets remains an expanding field of research, and this field has many important implications for human health.

Free-Radical Scavenger NSP-116 Protects the Corneal Epithelium against UV-A and Blue LED Light Exposure

The corneal epithelium is continuously exposed to oxygen, light, and environmental substances. Excessive exposure to those stresses is thought to be a risk factor for eye diseases. Photokeratitis is damage to the corneal epithelium resulting in a painful eye condition caused by unprotected exposure to UV rays, usually from sunlight, and is often found in people who spend a long time outdoors. In modern life, human eyes are exposed to artificial light from light-emitting diode (LED) displays of computers and smartphones, and it has been shown that short-wavelength (blue) LED light can damage eyes, especially photoreceptors. However, the effect of blue LED light on the cornea is less understood. In addition, it is important to develop new treatments for preserving human eyesight and eye health from light stress. Here, we used human corneal epithelial cells-transformed (HCE-T) cells as an in-vitro model to investigate the protective effect of NSP-116, an imidazolyl aniline derivative, against the oxidative stress induced by light in the corneal epithelium. Treatment with 10 µM NSP-116 significantly increased the cell viability and reduced the death ratio following UV or blue LED light exposure. Furthermore, NSP-116 treatment decreased light-induced reactive oxygen species production and preserved the mitochondrial membrane potential. Immunoblotting data showed that NSP-116 suppressed the stress response pathway. Finally, NSP-116 treatment prevented corneal epithelial apoptosis induced by blue LED light in an in-vivo mouse model. In conclusion, NSP-116 has a protective effect against oxidative stress and corneal cell death from both UV and blue LED light exposure.

Lycorine inhibits cell proliferation, migration and invasion, and primarily exerts in vitro cytostatic effects in human colorectal cancer via activating the ROS/p38 and AKT signaling pathways

Colorectal cancer (CRC) is a life‑threatening malignant tumor of the digestive tract. Diverse gene mutations and complicated alterations to the signaling pathways in CRC lead to heterogeneity in response to chemotherapy. Moreover, anticancer drugs for CRC chemotherapy are limited due to adverse events. Therefore, developing more effective, tolerable and safe drugs for the treatment of CRC is important. The present study aimed to investigate the effect of lycorine on human CRC cell proliferation, migration, invasion, apoptosis, cell cycle distribution, as well as the underlying molecular mechanism. The crystal violet staining and MTT assay results demonstrated that lycorine suppressed cell proliferation in a dose‑ and time‑dependent manner in the three CRC cell lines, HCT116, LoVo and SW480. Similarly, verified by performing wound healing and Transwell assays, lycorine significantly inhibited HCT116 and LoVo cell migration and invasion in vitro compared with the control group. In LoVo cells, the protein expression levels of matrix metallopeptidases, snail family transcriptional repressor 1, Vimentin and N‑cadherin were significantly downregulated, whereas the protein expression levels of E‑cadherin were significantly upregulated by lycorine treatment compared with the control group. The Hoechst 33258 staining and flow cytometry assay results indicated that lycorine mediated its cytostatic effect on CRC cells potentially via inducing cell cycle arrest, but not apoptosis. Compared with the control group, lycorine significantly induced HCT116 cell cycle arrest at the G2/M phase, but significantly induced LoVo cell cycle arrest at the S and G2/M phases. Furthermore, lycorine significantly downregulated the protein expression levels of cyclin D1 and cyclin E1, but significantly increased p21 and Smad4 protein expression levels in HCT116 and LoVo cells compared with the control group. The intracellular reactive oxygen species (ROS) measurement results also indicated that compared with the control group, lycorine significantly induced ROS accumulation, and increased phosphorylated‑p38 expression levels and AKT phosphorylation. Collectively, the present study suggested that lycorine might induce cell cycle arrest and exert cytostatic effects potentially via activating ROS/p38 and AKT signaling pathways in CRC cells.

Synthesis and Biological Evaluation of 2,3,4-Triaryl-1,2,4-oxadiazol-5-ones as p38 MAPK Inhibitors

A series of azastilbene derivatives, characterized by the presence of the 1,2,4-oxadiazole-5-one system as a linker of the two aromatic rings of stilbenes, have been prepared as novel potential inhibitors of p38 MAPK. Biological assays indicated that some of the synthesized compounds are endowed with good inhibitory activity towards the kinase. Molecular modeling data support the biological results showing that the designed compounds possess a reasonable binding mode in the ATP binding pocket of p38α kinase with a good binding affinity.

Microphysiological system modeling of ochratoxin A-associated nephrotoxicity

Ochratoxin A (OTA) is one of the most abundant mycotoxin contaminants in food stuffs and possesses carcinogenic, nephrotoxic, teratogenic, and immunotoxic properties. Specifically, a major concern is severe nephrotoxicity, which is characterized by degeneration of epithelial cells of the proximal tubules and interstitial fibrosis. However, the mechanism of OTA toxicity, as well as the genetic risk factors contributing to its toxicity in humans has been elusive due to the lack of adequate models that fully recapitulate human kidney function in vitro. The present study attempts to evaluate dose-response relationships, identify the contribution of active transport proteins that govern the renal disposition of OTA, and determine the role of metabolism in the bioactivation and detoxification of OTA using a 3D human kidney proximal tubule microphysiological system (kidney MPS). We demonstrated that LC50 values of OTA in kidney MPS culture (0.375-1.21 μM) were in agreement with clinically relevant toxic concentrations of OTA in urine. Surprisingly, no enhancement of kidney injury biomarkers was evident in the effluent of the kidney MPS after OTA exposure despite significant toxicity observed by LIVE/DEAD staining. Instead, these biomarkers decreased in an OTA concentration-dependent manner. Furthermore, the effect of 1-aminobenzotriazole (ABT) and 6-(7-Nitro-2,1,3-benzoxadiazol-4-ylthio) hexanol (NBDHEX), pan-inhibitors of P450 and glutathione S-transferase (GST) enzymes, respectively, on OTA-induced toxicity in kidney MPS was examined. These studies revealed significant enhancement of OTA-induced toxicity by NBDHEX (3 μM) treatment, whereas ABT (1 mM) treatment decreased OTA-induced toxicity, suggesting roles for GSTs and P450 enzymes in the detoxification and bioactivation of OTA, respectively. Analysis of transcriptional changes using RNA-sequencing of kidney MPS treated with different concentrations of OTA revealed downregulation of several nuclear factor (erythroid derived-2)-like 2 (NRF2)-regulated genes by OTA treatment, including GSTs. The transcriptional repression of GSTs is likely playing a key role in OTA toxicity via attenuation of glutathione conjugation/detoxification. The sequential molecular events may explain the mechanism of toxicity associated with OTA. Additionally, OTA transport studies using kidney MPS in the presence and absence of probenecid (1 mM) suggested a role for organic anionic membrane transporter(s) in the kidney specific disposition of OTA. Our findings provide a clearer understanding of the mechanism of OTA-induced kidney injury, which may support changes in risk assessment, regulatory agency policies on allowable exposure levels, and determination of the role of genetic factors in populations at risk for OTA nephrotoxicity.

Dexmedetomidine Attenuates Cellular Injury and Apoptosis in H9c2 Cardiomyocytes by Regulating p-38MAPK and Endoplasmic Reticulum Stress

Background

Myocardial ischaemia-reperfusion injury (IRI) has been confirmed to induce endoplasmic reticulum stress (ERS) when myocardial cell function continues to deteriorate to a certain degree. The clinical applications of effective tested strategies are sometimes inconsistent with the applications evaluated in experiments, although reasonable mechanisms and diverse signalling pathways have been broadly explored. Dexmedetomidine (DEX) has been shown to attenuate IRI of the heart in animal studies. This study aimed to determine whether DEX can protect injured cardiomyocytes under hypoxia/reoxygenation (H/R) at the cellular level and whether the mechanism is related to ERS and the p38 MAPK pathway.

Methods

H9c2 cells were subjected to H/R or thapsigargin (TG) to build a model. DEX or 4-PBA was added to the medium either 1 h or 24 h before modelling, respectively. Model parameters were determined by assessing cell viability and injury, which were measured by assessing cell counting kit-8 (CCK8), lactate dehydrogenase (LDH) release and flow cytometry results, and the expression of GRP78, CHOP and caspase-12. In addition, the protein expression of p38MAPK and p-p38MAPK was examined, and SB202190, a negative regulator, was also preincubated in medium.

Results

Compared to that of cells in the control group, the activity of cells in the H/R and TG groups was decreased dramatically, and the LDH concentration and proportion of apoptotic cells were increased. DEX could correspondingly reverse the changes induced by H/R or TG. Additionally, DEX effectively attenuated ERS defined as increased expression of GRP78, CHOP and caspase-12. Additionally, DEX could obviously depress the P38 MAPK phosphorylation and high p-p38 MAPK expression in the TG group, indicating DEX has a function similar to that of SB202190.

Conclusion

H/R injury in H9c2 cells can lead to abnormal ERS and apoptosis, as well as activation of the p38MAPK signalling pathway. DEX can protect cardiomyocytes by intervening in ERS, regulating p38MAPK and the downstream apoptotic signalling pathway.

Stretch, scratch, and stress: Suppressors and supporters of senescence in human fetal membranes

INTRODUCTION

Throughout gestation, amnion membranes undergo mechanical and or physiological stretch, scratch, or stress which is withstood by repairing and remodeling processes to protect the growing fetus. At term, increased oxidative stress (OS) activates p38MAPK, induces senescence, and inflammation contributing to membrane dysfunction to promote labor. However, the signaling initiated by stretch and scratch is still unclear. This study compares the induction of p38MAPK mediated senescence by stretch, scratch, and stress in human amnion epithelial cells (AECs).

METHODS

Primary AECs from term, not-in-labor, fetal membranes were cultured using the following conditions (N = 3); 1) CellFlex chambers with or without 20% biaxial stretch, 2) 8-well coverslips with or without scratch, and 3) cells exposed to cigarette smoke extract (CSE) inducing OS. p38MAPK (Western blot or immunocytochemistry), senescence activation, and inflammation (matrix metalloproteinases 9 [MMP9] activity-ELISA) were determined in cells exposed to various conditions. T-test and One-Way ANOVA was used to assess significance.

RESULTS

Biological membrane extension, mimicked by 20% biaxial stretch of AEC, maintained an epithelial morphology and activated P-p38MAPK (P = 0.02) compared to the non-stretch controls, but did not induce senescence or MMP9 activation. AEC scratches were healed within 40-hrs, which included proliferation, migration, and cellular transitions aided by p38MAPK activation but not senescence. CSE induced OS increased p38MAPK (P = 0.018) activation, senescence (P = 0.019), and MMP9 (P = 0.02).

CONCLUSION

Physiologic stretch and scratch experienced during gestation can cause p38MAPK activation without causing senescence or inflammation. This may be indicative of p38MAPK's role in tissue remodeling during pregnancy. Overwhelming OS, experienced at term, results in P-p38MAPK mediated senescence and inflammation to disrupt membrane remodeling.

Anticancer targets and mechanisms of calycosin to treat nasopharyngeal carcinoma

Calycosin is a naturally occurring phytoestrogen, and it has the anti-nasopharyngeal carcinoma (NPC) action played by calycosin. However, the elaborate mechanisms of calycosin treating NPC remain to be unrevealed. In current report, a promising tool of network pharmacology method was used to uncover the anti-NPC targets and therapeutic mechanisms played by calycosin. Furthermore, were conducted to validate the bioinformatic findings in human and preclinical studies. As results, the bioinformatic findings showed the core anti-NPC targets played by calycosin included tumor protein p53 (TP53), mitogen-activated protein kinase 14 (MAPK14), caspase 8 (CASP8), mitogen-activated protein kinase 3 (MAPK3), caspase 3 (CASP3), receptor interacting protein kinase 1 (RIPK1), proto-oncogene c (JUN), and estrogen receptor 1 (ESR1). Concurrently, the top 20 biological processes and top 20 pharmacological pathways of calycosin treating NPC were identified and illustrated. In clinical data, NPC samples showed up-regulated expression of MAPK14, reduced TP53, and CASP8 expressions in comparison with those in non-NPC controls. As revealed in experimental data, calycosin-treated NPC cells resulted in reduced cell survival rate, increased cell apoptosis. In apoptosis-specific staining, calycosin-treated NPC cells exhibited elevated apoptotic cell number. Following the immunostaining assays, the results indicated increased TP53-, CASP8-positive cells, and reduced MAPK14-positive cells in calycosin-treated NPC cells and xenograft tumor sections. Altogether, the bioinformatic findings from network pharmacology reveal all core targets and mechanisms of calycosin treating NPC, and some of bioinformatic findings are identified using human and preclinical experiments. Notably, the screened biotargets may be potentially used to clinically treat NPC.

Effect of Acupuncture on the p38 Signaling Pathway in Several Nervous System Diseases: A Systematic Review

Acupuncture is clinically used to treat various diseases and exerts positive local and systemic effects in several nervous system diseases. Advanced molecular and clinical studies have continually attempted to decipher the mechanisms underlying these effects of acupuncture. While a growing understanding of the pathophysiology underlying several nervous system diseases shows it to be related to inflammation and impair cell regeneration after ischemic events, the relationship between the therapeutic mechanism of acupuncture and the p38 MAPK signal pathway has yet to be elucidated. This review discusses the latest advancements in the identification of the effect of acupuncture on the p38 signaling pathway in several nervous system diseases. We electronically searched databases including PubMed, Embase, and the Cochrane Library from their inception to April 2020, using the following keywords alone or in various combinations: "acupuncture", "p38 MAPK pathway", "signaling", "stress response", "inflammation", "immune", "pain", "analgesic", "cerebral ischemic injury", "epilepsy", "Alzheimer's disease", "Parkinson's disease", "dementia", "degenerative", and "homeostasis". Manual acupuncture and electroacupuncture confer positive therapeutic effects by regulating proinflammatory cytokines, ion channels, scaffold proteins, and transcription factors including TRPV1/4, Nav, BDNF, and NADMR1; consequently, p38 regulates various phenomena including cell communication, remodeling, regeneration, and gene expression. In this review article, we found the most common acupoints for the relief of nervous system disorders including GV20, GV14, ST36, ST37, and LI4. Acupuncture exhibits dual regulatory functions of activating or inhibiting different p38 MAPK pathways, contributing to an overall improvement of clinical symptoms and function in several nervous system diseases.

Paternal restraint stress affects offspring metabolism via ATF-2 dependent mechanisms in Drosophila melanogaster germ cells

Paternal environmental factors can epigenetically influence gene expressions in offspring. We demonstrate that restraint stress, an experimental model for strong psychological stress, to fathers affects the epigenome, transcriptome, and metabolome of offspring in a MEKK1-dATF2 pathway-dependent manner in Drosophila melanogaster. Genes involved in amino acid metabolism are upregulated by paternal restraint stress, while genes involved in glycolysis and the tricarboxylic acid (TCA) cycle are downregulated. The effects of paternal restraint stress are also confirmed by metabolome analysis. dATF-2 is highly expressed in testicular germ cells, and restraint stress also induces p38 activation in the testes. Restraint stress induces Unpaired 3 (Upd3), a Drosophila homolog of Interleukin 6 (IL-6). Moreover, paternal overexpression of upd3 in somatic cells disrupts heterochromatin in offspring but not in offspring from dATF-2 mutant fathers. These results indicate that paternal restraint stress affects metabolism in offspring via inheritance of dATF-2-dependent epigenetic changes.

Ki-Hyeon Seong et al. report that paternal environmental stress affects the metabolism of their offspring in Drosophila melanogaster. They exposed male flies to stress by preventing them from moving for 10 hours at a time and then measured gene expression and metabolite levels in their offspring, who showed increased expression of amino acid and one-carbon metabolism-related genes and downregulation of glycolysis and the TCA cycle.

The p38 Pathway: From Biology to Cancer Therapy

The p38 MAPK pathway is well known for its role in transducing stress signals from the environment. Many key players and regulatory mechanisms of this signaling cascade have been described to some extent. Nevertheless, p38 participates in a broad range of cellular activities, for many of which detailed molecular pictures are still lacking. Originally described as a tumor-suppressor kinase for its inhibitory role in RAS-dependent transformation, p38 can also function as a tumor promoter, as demonstrated by extensive experimental data. This finding has prompted the development of specific inhibitors that have been used in clinical trials to treat several human malignancies, although without much success to date. However, elucidating critical aspects of p38 biology, such as isoform-specific functions or its apparent dual nature during tumorigenesis, might open up new possibilities for therapy with unexpected potential. In this review, we provide an extensive description of the main biological functions of p38 and focus on recent studies that have addressed its role in cancer. Furthermore, we provide an updated overview of therapeutic strategies targeting p38 in cancer and promising alternatives currently being explored.

p38MAPK controls fibroblast growth factor 23 (FGF23) synthesis in UMR106-osteoblast-like cells and in IDG-SW3 osteocytes

BACKGROUND

p38 mitogen-activated protein kinase (p38MAPK) is a serine/threonine kinase activated by cellular stress stimuli including radiation, osmotic shock, and inflammation and influencing apoptosis, cell proliferation, and autophagy. Moreover, p38MAPK induces transcriptional activity of the transcription factor complex NFκB mediating multiple pro-inflammatory cellular responses. Fibroblast growth factor 23 (FGF23) is produced by bone cells, and regulates renal phosphate and vitamin D metabolism as a hormone. FGF23 expression is enhanced by NFκB. Here, we analyzed the relevance of p38MAPK activity for the production of FGF23.

METHODS

Fgf23 expression was analyzed by qRT-PCR and FGF23 protein by ELISA in UMR106 osteoblast-like cells and in IDG-SW3 osteocytes.

RESULTS

Inhibition of p38MAPK with SB203580 or SB202190 significantly down-regulated Fgf23 expression and FGF23 protein expression. Conversely, p38MAPK activator anisomycin increased the abundance of Fgf23 mRNA. NFκB inhibitors wogonin and withaferin A abrogated the stimulatory effect of anisomycin on Fgf23 gene expression.

CONCLUSION

p38MAPK induces FGF23 formation, an effect at least in part dependent on NFκB activity.

Involvement of p38 MAPK pathway in benzo(a)pyrene-induced human hepatoma cell migration and invasion

The objective of this study was to investigate the potential role of p38 mitogen-activated protein kinases (MAPK) in benzo(a)pyrene (BaP)-induced hepatoma cell migration and invasion. Western blot assay was applied to detect the expression of proteins. qRT-PCR assay was used to measure the expression of mRNA. Wound healing assay and Transwell invasion assay were performed to evaluate cell migratory ability and cell invasive ability, respectively. Our data showed that BaP exposure increased the expression of p-p38 protein in human hepatoma HepG2 cells. Exposure to BaP facilitated HepG2 cell migration and invasion, which could be blocked by p38 MAPK inhibitors. In addition, BaP exposure induced upregulation of MMP9 mRNA expression, which was modulated by p-p38. In conclusion, p38 MAPK pathway was involved in BaP-induced hepatoma cell migration and invasion.

NK007 helps in mitigating paclitaxel resistance through p38MAPK activation and HK2 degradation in ovarian cancer

Ovarian cancer resistance to available medicines is a huge challenge in dire need of a solution, which makes its recurrence and mortality rate further exacerbated. A promising approach to overcome chemoresistance is drug screening from natural products. Here, we report that NK007, a (±)-tylophorine malate isolated from the Asclepiadaceae family, selectively inhibited the proliferation of A2780 and A2780 (Taxol) cells and migration of paclitaxel-sensitive and -resistant ovarian cancer cells. Interestingly, the decline of cell viability, including cell multiplication, clonality, and migration capacity was independent on cell apoptosis. At the molecular level, NK007 considerably induced G1/S arrest and upregulated the expression of phospho-p38 mitogen-activated protein kinase (p-p38MAPK). In addition, hexokinase 2 (HK2) protein degradation was considerably elevated in the presence of NK007, which resulted in the reduction of oxygen consumption rate and extracellular acidification rate. Altogether, our results indicate that NK007, an analog of tylophorine, can overcome paclitaxel (PTX) resistance through p38MAPK activation and HK2 degradation. As an effective, alternative antiresistance agent, NK007 exhibits a promising potential to treat PTX-resistant ovarian cancer.

Fatigue, Sleep, and Autoimmune and Related Disorders

Profound and debilitating fatigue is the most common complaint reported among individuals with autoimmune disease, such as systemic lupus erythematosus, multiple sclerosis, type 1 diabetes, celiac disease, chronic fatigue syndrome, and rheumatoid arthritis. Fatigue is multi-faceted and broadly defined, which makes understanding the cause of its manifestations especially difficult in conditions with diverse pathology including autoimmune diseases. In general, fatigue is defined by debilitating periods of exhaustion that interfere with normal activities. The severity and duration of fatigue episodes vary, but fatigue can cause difficulty for even simple tasks like climbing stairs or crossing the room. The exact mechanisms of fatigue are not well-understood, perhaps due to its broad definition. Nevertheless, physiological processes known to play a role in fatigue include oxygen/nutrient supply, metabolism, mood, motivation, and sleepiness-all which are affected by inflammation. Additionally, an important contributing element to fatigue is the central nervous system-a region impacted either directly or indirectly in numerous autoimmune and related disorders. This review describes how inflammation and the central nervous system contribute to fatigue and suggests potential mechanisms involved in fatigue that are likely exhibited in autoimmune and related diseases.

Exhausted and Senescent T Cells at the Maternal-Fetal Interface in Preterm and Term Labor

Successful pregnancy requires a tightly-regulated equilibrium of immune cell interactions at the maternal-fetal interface (i.e., the decidual tissues), which plays a central role in the inflammatory process of labor. Most of the innate immune cells in this compartment have been well characterized; however, adaptive immune cells are still under investigation. Herein, we performed immunophenotyping of the decidua basalis and decidua parietalis to determine whether exhausted and senescent T cells are present at the maternal-fetal interface and whether the presence of pathological (i.e., preterm) or physiological (i.e., term) labor and/or placental inflammation alter such adaptive immune cells. In addition, decidual exhausted T cells were sorted to test their functional status. We found that (1) exhausted and senescent T cells were present at the maternal-fetal interface and predominantly expressed an effector memory phenotype, (2) exhausted CD4⁺ T cells increased in the decidua parietalis as gestational age progressed, (3) exhausted CD4⁺ and CD8⁺ T cells decreased in the decidua basalis of women who underwent labor at term compared to those without labor, (4) exhausted CD4⁺ T cells declined with the presence of placental inflammation in the decidua basalis of women with preterm labor, (5) exhausted CD8⁺ T cells decreased with the presence of placental inflammation in the decidua basalis of women who underwent labor at term, (6) both senescent CD4⁺ and CD8⁺ T cells declined with the presence of placental inflammation in the decidua basalis of women who underwent preterm labor, and (7) decidual exhausted T cells produced IFNγ and TNFα upon in vitro stimulation. Collectively, these findings indicate that exhausted and senescent T cells are present at the human maternal-fetal interface and undergo alterations in a subset of women either with labor at term or preterm labor and placental inflammation. Importantly, decidual T cell function can be restored upon stimulation.

Lipopolysaccharides-mediated injury to chondrogenic ATDC5 cells can be relieved by Sinomenine via downregulating microRNA-192

Sinomenine (SIN) is an isoquinoline derived from Caulis Sinomenii that has been used to treat rheumatoid arthritis and osteoarthritis for several decades in China. This study aims to reveal the effects of SIN on mouse chondrogenic ATDC5 cells growth and inflammation. SIN was used to treat ATDC5 cells injured by lipopolysaccharides (LPS). The following parameters were determined for evaluating the treatment effects of SIN: cell viability, apoptosis, reactive oxygen species generation, and pro-inflammatory cytokines release. Besides, the expression of LPS-sensitive miRNA (miR-192) and the activation of NF-κB and MAPK signaling were studied to explain SIN's function. SIN with concentration of 30 μM significantly attenuated LPS-induced cell damage via increasing cell viability, inhibiting apoptosis and reactive oxygen species generation, and declining IL-6 and TNF-α release. miR-192 was downregulated by SIN treatment. Restoration of miR-192 expression by miRNA transfection could significantly impede SIN's protective action. Besides, the inhibitory effects of SIN on the activation of NF-κB and MAPK signaling were attenuated by miR-192 overexpression. Furthermore, GDF11 was found to be a target gene of miR-192. LPS-mediated injury to chondrogenic ATDC5 cells can be relieved by SIN via downregulating miR-192 and subsequently repressing the activation of NF-κB and MAPK signaling.

The PI3K and MAPK/p38 pathways control stress granule assembly in a hierarchical manner

PI3K and p38 act in a hierarchical manner to enhance mTORC1 activity and stress granule formation; although PI3K is the main driver, the impact of p38 gets apparent as PI3K activity declines.

All cells and organisms exhibit stress-coping mechanisms to ensure survival. Cytoplasmic protein-RNA assemblies termed stress granules are increasingly recognized to promote cellular survival under stress. Thus, they might represent tumor vulnerabilities that are currently poorly explored. The translation-inhibitory eIF2α kinases are established as main drivers of stress granule assembly. Using a systems approach, we identify the translation enhancers PI3K and MAPK/p38 as pro-stress-granule-kinases. They act through the metabolic master regulator mammalian target of rapamycin complex 1 (mTORC1) to promote stress granule assembly. When highly active, PI3K is the main driver of stress granules; however, the impact of p38 becomes apparent as PI3K activity declines. PI3K and p38 thus act in a hierarchical manner to drive mTORC1 activity and stress granule assembly. Of note, this signaling hierarchy is also present in human breast cancer tissue. Importantly, only the recognition of the PI3K-p38 hierarchy under stress enabled the discovery of p38’s role in stress granule formation. In summary, we assign a new pro-survival function to the key oncogenic kinases PI3K and p38, as they hierarchically promote stress granule formation.

Comprehensive analyses of DNA methylation and gene expression profiles of Kawasaki disease

OBJECTIVE

Kawasaki disease (KD) is a childhood febrile vasculitis with unknown etiology. Epigenetic regulation in the gene expression dynamics has become increasingly important in KD. Thus, we performed an integrated analysis of DNA methylation and gene expression data to identify novel molecular mechanisms and key functional genes in KD.

METHODS

DNA methylation (GSE84624) and gene expression (GSE68004) datasets were downloaded from Gene Expression Omnibus. Methylated-differentially expressed genes (mDEGs) were documented as the overlapping genes between the differentially methylated genes (DMGs) in GSE84624 and differentially expressed genes (DEGs) in GSE68004. Functional enrichment analyses of the mDEGs were conducted using DAVID database. Protein-protein interaction (PPI) network was then constructed to obtain the hub genes involved in KD using STRING database.

RESULTS

A total of 1389 DMGs and 1362 DEGs were screened out between KD and control samples. Overlapping of them resulted in four hypermethylated/downregulated and 187 hypomethylated/upregulated genes. These mDEGs were mainly enriched in inflammation response, innate immune response, and blood coagulation, and signaling pathways such as platelet activation, osteoclast differentiation, and chemokine signaling pathway. PPI network analyses identified MAPK14 and PHLPP1 as the hub genes involved in KD, which could distinguish KD from other common pediatric febrile diseases. In addition, the methylation and expression levels of MAPK14 and PHLPP1 were validated in other independent datasets.

CONCLUSION

This study provides an integrated view of interactions among DNA methylation and gene expression in patients with KD. MAPK14 and PHLPP1 are the key genes influenced by methylation and may serve as candidate biomarkers for KD.

PP-22 promotes autophagy and apoptosis in the nasopharyngeal carcinoma cell line CNE-2 by inducing endoplasmic reticulum stress, downregulating STAT3 signaling, and modulating the MAPK pathway

Paris polyphylla var. yunnanensis, named Chong Lou, is considered an antitumor substance. In this study, we investigated the effect of PP-22, a monomer purified from P. polyphylla var. yunnanensis, on the nasopharyngeal carcinoma cell line CNE-2 in vitro. The results showed that PP-22 could inhibit the proliferation of CNE-2 cells via the induction of apoptosis, with evidence of the characteristic morphological changes in the apoptosis in the nucleus and an increase in Annexin V-positive cells. In addition, we found that PP-22 could activate the p38 mitogen-activated protein kinase (MAPK) pathway and that this activation was reversed by SB203580, a specific inhibitor of the p38 MAPK pathway. In contrast, PP-22 promoted apoptosis via an intrinsic pathway, including the endoplasmic reticulum stress pathway, in a caspase-dependent manner. A further study showed that PP-22 also induced apoptosis by downregulating the signal transducers and activators of transcription 3 (STAT3) pathway, and the inhibitory effect was also confirmed by STAT3 small interfering RNA. In addition, PP-22 could promote autophagy by inhibiting the extracellular regulated protein kinases (ERK) pathway. And autophagy plays a protective role against apoptosis. Together, these data show that PP-22 promotes autophagy and apoptosis in the nasopharyngeal carcinoma CNE-2 cell line.

Role of p38 MAPK in Atherosclerosis and Aortic Valve Sclerosis

Atherosclerosis and aortic valve sclerosis are cardiovascular diseases with an increasing prevalence in western societies. Statins are widely applied in atherosclerosis therapy, whereas no pharmacological interventions are available for the treatment of aortic valve sclerosis. Therefore, valve replacement surgery to prevent acute heart failure is the only option for patients with severe aortic stenosis. Both atherosclerosis and aortic valve sclerosis are not simply the consequence of degenerative processes, but rather diseases driven by inflammatory processes in response to lipid-deposition in the blood vessel wall and the aortic valve, respectively. The p38 mitogen-activated protein kinase (MAPK) is involved in inflammatory signaling and activated in response to various intracellular and extracellular stimuli, including oxidative stress, cytokines, and growth factors, all of which are abundantly present in atherosclerotic and aortic valve sclerotic lesions. The responses generated by p38 MAPK signaling in different cell types present in the lesions are diverse and might support the progression of the diseases. This review summarizes experimental findings relating to p38 MAPK in atherosclerosis and aortic valve sclerosis and discusses potential functions of p38 MAPK in the diseases with the aim of clarifying its eligibility as a pharmacological target.

Oxidative stress-induced TGF-beta/TAB1-mediated p38MAPK activation in human amnion epithelial cells

Term and preterm parturition are associated with oxidative stress (OS)-induced p38 mitogen-activated protein kinase (p38MAPK)-mediated fetal tissue (amniochorion) senescence. p38MAPK activation is a complex cell- and stimulant-dependent process. Two independent pathways of OS-induced p38MAPK activation were investigated in amnion epithelial cells (AECs) in response to cigarette smoke extract (CSE: a validated OS inducer in fetal cells): (1) the OS-mediated oxidation of apoptosis signal-regulating kinase (ASK)-1 bound Thioredoxin (Trx[SH]2) dissociates this complex, creating free and activated ASK1-signalosome and (2) transforming growth factor-mediated activation of (TGF)-beta-activated kinase (TAK)1 and TGF-beta-activated kinase 1-binding protein (TAB)1. AECs isolated from normal term, not-in-labor fetal membranes increased p38MAPK in response to CSE and downregulated it in response to antioxidant N-acetylcysteine. In AECs, both Trx and ASK1 were localized; however, they remained dissociated and not complexed, regardless of conditions. Silencing either ASK1 or its downstream effectors (MKK3/6) did not affect OS-induced p38MAPK activation. Conversely, OS increased TGF-beta's release from AECs and increased phosphorylation of both p38MAPK and TAB1. Silencing of TAB1, but not TAK1, prevented p38MAPK activation, which is indicative of TAB1-mediated autophosphorylation of p38MAPK, an activation mechanism seldom seen. OS-induced p38MAPK activation in AECs is ASK1-Trx signalosome-independent and is mediated by the TGF-beta pathway. This knowledge will help to design strategies to reduce p38MAPK activation-associated pregnancy risks.

Regulation of p38 mitogen-activated kinase-mediated fetal membrane senescence by statins

PROBLEM

Oxidative stress (OS)-induced, p38 mitogen-activated protein kinase (p38MAPK)-mediated chorioamniotic senescence and inflammation (senescence-associated secretory phenotype [SASP]) are associated with parturition. In response to OS-inducing risk factors, premature senescence contributes to preterm premature rupture of the membranes (pPROM) and spontaneous preterm birth (PTB). We determined the effect of simvastatin, rosuvastatin, and progesterone in downregulating p38MAPK-mediated senescence and SASP.

METHOD OF STUDY

Normal term, not-in-labor fetal membranes (n = 8) were exposed to cigarette smoke extract (CSE: OS inducer) alone or combined with simvastatin (100 and 200 ng/mL), rosuvastatin (100 and 200 ng/mL), and progesterone (10^-6  mol/L). p38MAPK expression changes were studied by Western blot, senescence was determined by senescence-associated β-Galactosidase (SA-β-Gal) staining, and multiplex analysis determined changes associated with 4 SASP markers (IL-8, IL-10, TNF-α, and GM-CSF). A pairwise comparison between groups was conducted by ANOVA.

RESULTS

Compared to untreated controls, CSE induced p38MAPK-mediated senescence and SASP. CSE cotreatment with simvastatin and rosuvastatin significantly reduced p38MAPK activation, senescence (decrease in SA-β-Gal) and SASP markers, GM-CSF, and TNF, but not IL-8, while increasing anti-inflammatory IL-10 in a dose-dependent manner. Cotreatment of CSE and progesterone had no effect on reducing p38MAPK activation, senescence, or SASP.

CONCLUSION

Both simvastatin and rosuvastatin downregulated OS-induced p38MAPK activation, senescence, and SASP, while rosuvastatin showed a pronounced effect. Progesterone did not reduce OS-induced fetal membrane senescence and SASP. Simvastatin or rosuvastatin may reduce the incidences of OS-associated PTB and pPROM by preventing premature senescence and SASP.

Understanding periviable birth: A microeconomic alternative to the dysregulation narrative

Periviable infants (i.e., those born in the 20th through 26th weeks of gestation) suffer much morbidity and approximately half die in the first year of life. Attempts to explain and predict these births disproportionately invoke a "dysregulation" narrative. Research inspired by this narrative has not led to efficacious interventions. The clinical community has, therefore, urged novel approaches to the problem. We aim to provoke debate by offering the theory, inferred from microeconomics, that risk tolerant women carry, without cognitive involvement, high risk fetuses farther into pregnancy than do other women. These extended high-risk pregnancies historically ended in stillbirth but modern obstetric practices now convert a fraction to periviable births. We argue that this theory deserves testing because it suggests inexpensive and noninvasive screening for pregnancies that might benefit from the costly and invasive interventions clinical research will likely devise.

Expression of Heat Shock Protein-27 (Hsp27) and P38MAPK in Esophageal Squamous Cell Carcinoma

Background

Esophageal squamous cell carcinoma (ESCC) is a worldwide concern. This study looked at the relationship between the expression of differential proteins and the clinicopathological data and survival rate of ESCC patients to identify potential tumor markers for the growth and metastasis of ESCC.

Material/Methods

This study included 162 patients who underwent surgical excision for management of ESCC. Fresh ESCC tissue and adjacent normal tissue specimens were collected. Protein expressions were detected by western blotting. The expression of Hsp27 and P38MAPK were detected by immunohistochemistry in formalin-fixed paraffin embedded primary tissue specimens.

Results

The rate of positive Hsp27 and P38MAPK expression in ESCC tissue were higher than in normal esophageal tissue (p<0.05). The expression of P38MAPK was related to the depth of infiltration (p<0.05). The expression of Hsp27 was correlated with lymph node metastasis (p<0.05), but not with age, depth of infiltration, or tumor size. ROC were plotted to estimate the significance of the diagnosis: for Hsp27, AUC=0.735 (p<0.05), for P38MAPK, AUC=0.882 (p<0.05).

Conclusions

The expression of Hsp27 and P38MAPK plays a role in ESCC development. Hsp27 and P38MAPK could be used as prognostic factors in ESCC.

Preterm labor in the absence of acute histologic chorioamnionitis is characterized by cellular senescence of the chorioamniotic membranes

BACKGROUND

Decidual senescence has been considered a mechanism of disease for spontaneous preterm labor in the absence of severe acute inflammation. Yet, signs of cellular senescence have also been observed in the chorioamniotic membranes from women who underwent the physiological process of labor at term.

OBJECTIVE

We aimed to investigate whether, in the absence of acute histologic chorioamnionitis, the chorioamniotic membranes from women who underwent spontaneous preterm labor or labor at term exhibit signs of cellular senescence.

STUDY DESIGN

Chorioamniotic membrane samples were collected from women who underwent spontaneous preterm labor or labor at term. Gestational age-matched nonlabor controls were also included. Senescence-associated genes/proteins were determined using reverse transcription quantitative polymerase chain reaction analysis (n = 7-9 each for array; n = 26-28 each for validation), enzyme-linked immunosorbent assays (n = 7-9 each), immunoblotting (n = 6-7 each), and immunohistochemistry (n = 7-8 each). Senescence-associated β-galactosidase activity (n = 7-11 each) and telomere length (n = 15-22 each) were also evaluated.

RESULTS

In the chorioamniotic membranes without acute histologic chorioamnionitis: (1) the expression profile of senescence-associated genes was different between the labor groups (term in labor and preterm in labor) and the nonlabor groups (term no labor and preterm no labor), yet there were differences between the term in labor and preterm in labor groups; (2) most of the differentially expressed genes among the groups were closely related to the tumor suppressor protein (TP53) pathway; (3) the expression of TP53 was down-regulated in the term in labor and preterm in labor groups compared to their nonlabor counterparts; (4) the expression of CDKN1A (gene coding for p21) was up-regulated in the term in labor and preterm in labor groups compared to their nonlabor counterparts; (5) the expression of the cyclin kinase CDK2 and cyclins CCNA2, CCNB1, and CCNE1 was down-regulated in the preterm in labor group compared to the preterm no labor group; (6) the concentration of TP53 was lower in the preterm in labor group than in the preterm no labor and term in labor groups; (7) the senescence-associated β-galactosidase activity was greater in the preterm in labor group than in the preterm no labor and term in labor groups; (8) the concentration of phospho-S6 ribosomal protein was reduced in the term in labor group compared to its nonlabor counterpart, but no differences were observed between the preterm in labor and preterm no labor groups; and (9) no significant differences were observed in relative telomere length among the study groups (term no labor, term in labor, preterm no labor, and preterm in labor).

CONCLUSION

In the absence of acute histologic chorioamnionitis, signs of cellular senescence are present in the chorioamniotic membranes from women who underwent spontaneous preterm labor compared to those who delivered preterm in the absence of labor. However, the chorioamniotic membranes from women who underwent spontaneous labor at term did not show consistent signs of cellular senescence in the absence of histologic chorioamnionitis. These results suggest that different pathways are implicated in the pathological and physiological processes of labor.