The MAP kinase signaling cascades: a system of hundreds of components regulates a diverse array of physiological functions

Helicobacter pylori reduces METTL14-mediated VAMP3 m6A modification and promotes the development of gastric cancer by regulating LC3C-mediated c-Met recycling

Helicobacter pylori (H. pylori) plays an important role in the malignant transformation of the gastric mucosa from chronic inflammation to cancer. However, the mechanisms underlying the epigenetic regulation of gastric carcinogenesis mediated by H. pylori remain unclear. Here, we uncover that H. pylori inhibits METTL14 by upregulating ATF3. METTL14 inhibits gastric cancer (GC) cell proliferation and metastasis in vitro and in vivo. Downregulation of METTL14 inhibits Vesicle-associated membrane protein-3 (VAMP3) by reducing the m6A modification level of VAMP3 mRNA and the stability of IGF2BP2-dependent mRNA. H. pylori also accelerates the malignant progression of GC by regulating VAMP3/LC3C-mediated c-Met recycling. Moreover, the expression of METTL14 and VAMP3 in Hp+ chronic gastritis tissues is much lower than that in Hp- chronic gastritis tissues. METTL14 and VAMP3 expression levels are downregulated notably in cancerous tissues of patients with GC. Therefore, our results show a novel METTL14-VAMP3-LC3C-c-Met signalling axis in the GC development mediated by H. pylori infection, which reveals a novel m6A epigenetic modification mechanism for GC and provides potential prognostic biomarkers for GC progression.

Mitogen-activated protein kinase-mediated regulation of plant specialized metabolism

Post-transcriptional and post-translational modification of transcription factors (TFs) and pathway enzymes significantly affect the stress-stimulated biosynthesis of specialized metabolites (SMs). Protein phosphorylation is one of the conserved and ancient mechanisms that critically influences many biological processes including specialized metabolism. The phosphorylation of TFs and enzymes by protein kinases (PKs), especially the mitogen-activated protein kinases (MAPKs), is well studied in plants. While the roles of MAPKs in plant growth and development, phytohormone signaling, and immunity are well elucidated, significant recent advances have also been made in understanding the involvement of MAPKs in specialized metabolism. However, a comprehensive review highlighting the significant progress in the past several years is notably missing. This review focuses on MAPK-mediated regulation of several important SMs, including phenylpropanoids (flavonoids and lignin), terpenoids (artemisinin and other terpenoids), alkaloids (terpenoid indole alkaloids and nicotine), and other nitrogen- and sulfur-containing SMs (camalexin and indole glucosinolates). In addition to MAPKs, other PKs also regulate SM biosynthesis. For comparison, we briefly discuss the regulation by other PKs, such as sucrose non-fermenting-1 (SNF)-related protein kinases (SnRKs) and calcium-dependent protein kinases (CPKs). Furthermore, we provide future perspectives in this active area of research.

Exploring the Complexity of Pan-Cancer: Gene Convergences and in silico Analyses

Cancer is a complex and multifaceted group of diseases characterized by highly intricate mechanisms of tumorigenesis and tumor progression, which complicates diagnosis, prognosis, and treatment. In recent years, targeted therapies have gained prominence by focusing on specific mutations and molecular features unique to each tumor type, offering more effective and personalized treatment options. However, it is equally critical to explore the genetic commonalities across different types of cancer, which has led to the rise of pan-cancer studies. These approaches help identify shared therapeutic targets across various tumor types, enabling the development of broader and potentially more widely applicable treatment strategies. This review aims to provide a comprehensive overview of key concepts related to tumors, including tumorigenesis processes, the tumor microenvironment, and the role of extracellular vesicles in tumor biology. Additionally, we explore the molecular interactions and mechanisms driving tumor progression, with a particular focus on the pan-cancer perspective. To achieve this, we conducted an in silico analysis using publicly available datasets, which facilitated the identification of both common and divergent genetic and molecular patterns across different tumor types. By integrating these diverse areas, this review offers a clearer and deeper understanding of the factors influencing tumorigenesis and highlights potential therapeutic targets.

Chronic Inflammation and Cancer: Key Pathways and Targeted Therapies

Recent research has underscored the pivotal role of chronic inflammation in cancer development. Investigations have elucidated key molecular mechanisms underpinning inflammation-related cancer. Extrinsic pathway, driven by inflammatory conditions and intrinsic pathway, propelled by genetic events, emerged as critical links between inflammation and carcinogenesis. The persistent inflammation exacerbates genomic instability, providing a mechanistic link between inflammation and cancer. Targeting crucial inflammatory pathways such as NFκB, JAK-STAT, MAPK/ERK, PI3K/AKT, Wnt and TGF-β, holds promise for advancing cancer treatment modalities. Hence, understanding the key signalling pathways will highlight the intricate interplay between inflammation and cancer recognizing it as a potential target for interventions.

Roles of Different Signaling Pathways in Cryptococcus neoformans Virulence

Cryptococcus neoformans is a widespread fungal pathogen that can infect the human central nervous system (CNS) and cause fungal meningitis, leading to hundreds of thousands of deaths worldwide each year. Previous studies have demonstrated that many signal transduction pathways are crucial for the morphological development and virulence of C. neoformans. In this review, data from over 116 research articles have been compiled to show that many signaling pathways control various characteristics of C. neoformans, individually or in association with other pathways, and to establish strong links among them to better understand C. neoformans pathogenesis. Every characteristic of C. neoformans is closely linked to these signaling pathways, making this a rich area for further research. It is essential to thoroughly explore these pathways to address questions that remain and apply a molecular mechanistic approach to link them. Targeting these pathways is crucial for understanding the exact mechanism of infection pathogenesis and will facilitate the development of antifungal drugs as well as the diagnosis and prevention of cryptococcosis.

Challenges in tendon-bone healing: emphasizing inflammatory modulation mechanisms and treatment

Tendons are fibrous connective tissues that transmit force from muscles to bones. Despite their ability to withstand various loads, tendons are susceptible to significant damage. The healing process of tendons and ligaments connected to bone surfaces after injury presents a clinical challenge due to the intricate structure, composition, cellular populations, and mechanics of the interface. Inflammation plays a pivotal role in tendon healing, creating an inflammatory microenvironment through cytokines and immune cells that aid in debris clearance, tendon cell proliferation, and collagen fiber formation. However, uncontrolled inflammation can lead to tissue damage, and adhesions, and impede proper tendon healing, culminating in scar tissue formation. Therefore, precise regulation of inflammation is crucial. This review offers insights into the impact of inflammation on tendon-bone healing and its underlying mechanisms. Understanding the inflammatory microenvironment, cellular interactions, and extracellular matrix dynamics is essential for promoting optimal healing of tendon-bone injuries. The roles of fibroblasts, inflammatory cytokines, chemokines, and growth factors in promoting healing, inhibiting scar formation, and facilitating tissue regeneration are discussed, highlighting the necessity of balancing the suppression of detrimental inflammatory responses with the promotion of beneficial aspects to enhance tendon healing outcomes. Additionally, the review explores the significant implications and translational potential of targeted inflammatory modulation therapies in refining strategies for tendon-bone healing treatments.

Special Issue: MAPK Signaling Cascades in Human Health and Diseases

In order to survive and fulfil their functions, cells of any organism need to be able to respond to a large number of extracellular factors, also termed extracellular stimuli [...].

Unveiling the intracellular dynamics of α4β2 nAChR-mediated ERK activation through the interplay of arrestin, Gβγ, and PKCβII

AIMS

In contrast to G protein-coupled receptors or receptor tyrosine kinases, the mechanism underlying ERK activation through nicotine acetylcholine receptors (nAChRs), members of the ligand-gated ion channel family, remains poorly elucidated. This study aimed to delineate the signaling pathway responsible for ERK activation by the α4β2 nAChR subtype, which is implicated in nicotine addiction and various mental disorders.

MATERIALS AND METHODS

Loss-of-function strategies and mutants of arrestin2/PKCβII with distinct functional characteristics were employed to identify the cellular components and processes involved in ERK activation.

KEY FINDINGS

ERK activation via α4β2 nAChR was observed within the nucleus and necessitated the nuclear translocation of arrestin2 and PKCβII, which exhibited mutual augmentation. Activation of PKCβII by α4β2 nAChR stimulation facilitated the nuclear translocation of arrestin2 by enhancing its interaction with importin β1. Apart from scaffolding ERK activation in the nucleus, arrestin2, in cooperation with GRK2, facilitated the activation of the Src/Syk/PKCβII signaling cascade, leading to the nuclear entry of PKCβII in a Gβγ-dependent manner. Upon nuclear localization, PKCβII underwent ubiquitination by Mdm2 and interacted with MEK1, resulting in ERK activation. In summary, α4β2 nAChR-mediated ERK activation in the nucleus involves the nuclear translocation of arrestin2 and PKCβII, which is reciprocally facilitated via positive feedback augmentation.

SIGNIFICANCE

As α4β2 nAChRs play a pivotal role in various cellular processes including drug addiction and mental disorders, our findings will offer insights into understanding the pathogenesis of α4β2 nAChR-related disorders and may facilitate the development of targeted therapeutic interventions.

Comprehensive analysis of MAPK genes in the prognosis, immune characteristics, and drug treatment of renal clear cell carcinoma using bioinformatic analysis and Mendelian randomization

Mitogen-activated protein kinase (MAPK) signalling is vitally important in tumour development and progression. This study is the first to comprehensively analyse the role of MAPK-family genes in the progression, prognosis, immune-cell infiltration, methylation, and potential therapeutic value drug candidates in ccRCC. We identified a novel prognostic panel of six MAPK-signature genes (MAP3K12, MAP3K1, MAP3K5, MAPK1, MAPK8, MAPK9), and introduced a robust MAPK-signature risk model for predicting ccRCC prognosis. Model construction, evaluation, and external validation using datasets from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) database demonstrated its stability, as well as high sensitivity and specificity. Enrichment analysis suggested the participation of immune-mediated mechanism in MAPK dysregulation in ccRCC. Immune-infiltration analysis confirmed the relationship and revealed that the MAPK-signature risk model might stratify immunotherapy response in ccRCC, which was verified in drug sensitivity analysis and validated in external ccRCC immunotherapy dataset (GSE67501). Potential therapeutic drug predictions for key MAPKs using DSigDB, Network Analyst, CTD, and DGIdb were subsequently verified by molecular docking with AutoDock Vina and PyMol. Mendelian randomization further demonstrated the possibilities of the MAPK-signature genes as targets for therapeutic drugs in ccRCC. Methylation analysis using UALCAN and MethSurv revealed the participation of epigenetic modifications in dysregulation and survival difference of MAPK pathway in ccRCC. Among the key MAPKs, MAP3K12 exhibited the highest significance, indicating its independent prognostic value as single gene in ccRCC. Knockout and overexpression validation experiments in vitro and in vivo found that MAP3K12 acted as a promoter of tumour progression in RCC, suggesting a pivotal role for MAP3K12 in the proliferation, migration, and invasion of RCC cells. Our findings proposed the potential of MAPK-signature genes as biomarkers for prognosis and therapy response, as well as targets for therapeutic drugs in ccRCC.

Identification of DNA methylation markers for age and Bovine Respiratory Disease in dairy cattle: A pilot study based on Reduced Representation Bisulfite Sequencing

Methylation profiles of animals are known to differ by age and disease status. Bovine respiratory disease (BRD), a complex infectious disease, primarily affects calves and has significant impact on animal welfare and the cattle industry, due to production losses, increased veterinary costs as well as animal losses. BRD susceptibility is multifactorial, influenced by both environmental and genetic factors. We have performed a pilot study to investigate the epigenetic profile of BRD susceptibility in six calves (three healthy versus three diagnosed with BRD) and age-related methylation differences between healthy calves and adult dairy cows (three calves versus four adult cows) using Reduced Representation Bisulfite Sequencing (RRBS). We identified 2537 genes within differentially methylated regions between calves and adults. Functional analysis revealed enrichment of developmental pathways including cell fate commitment and tissue morphogenesis. Between healthy and BRD affected calves, 964 genes were identified within differentially methylated regions. Immune and vasculature regulatory pathways were enriched and key candidates in BRD susceptibility involved in complement cascade regulation, vasoconstriction and respiratory cilia structure and function were identified. Further studies with a greater sample size are needed to validate these findings and formulate integration into breeding programmes aiming to increase animal longevity and disease resistance.

Statins enhance extracellular release of hepatitis C virus particles through ERK5 activation

Statins, such as lovastatin, have been known to inhibit 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase. Statins were reported to moderately suppress hepatitis C virus (HCV) replication in cultured cells harboring HCV RNA replicons. We report here using an HCV cell culture (HCVcc) system that high concentrations of lovastatin (5-20 μg/mL) markedly enhanced the release of HCV infectious particles (virion) in the culture supernatants by up to 40 times, without enhancing HCV RNA replication, HCV protein synthesis, or HCV virion assembly in the cells. We also found that lovastatin increased the phosphorylation (activation) level of extracellular-signal-regulated kinase 5 (ERK5) in both the infected and uninfected cells in a dose-dependent manner. The lovastatin-mediated increase of HCV virion release was partially reversed by selective ERK5 inhibitors, BIX02189 and XMD8-92, or by ERK5 knockdown using small interfering RNA (siRNA). Moreover, we demonstrated that other cholesterol-lowering statins, but not dehydrolovastatin that is incapable of inhibiting HMG-CoA reductase and activating ERK5, enhanced HCV virion release to the same extent as observed with lovastatin. These results collectively suggest that statins markedly enhance HCV virion release from infected cells through HMG-CoA reductase inhibition and ERK5 activation.

Unraveling effective extracellular signal-regulated kinase 2 inhibitors: a de novo drug design strategy enhanced by in-depth in silico analyses

Extracellular signal-regulated kinase 2 (ERK-2) is a serine/threonine protein kinase in eukaryotic cells and belongs to the mitogen-activated protein kinase (MAPK) family. An activated form of ERK-2 phosphorylates substrates in the nucleus or cytoplasm and causes specific proteins to be expressed or activated, regulating cell proliferation, differentiation and other functions. Caffeic acid (3,4 - dihydroxy cinnamic acid), as previously reported, directly interacts with ERK-2 and reduces its effects in vitro. It is also reported to have a variety of pharmacological effects, including anti-inflammatory, immunomodulatory, antioxidant and anticancer activities. In the current study, a deep-learning protocol was employed to develop effective 100 compounds by modifying the chemical structure of DHC to improve its inhibitory performance against ERK-2. Calculations of physicochemical properties for those compounds revealed that 20 compounds had drug scores better than DHC (≥ 80%). Following that, molecular docking calculations were performed on the selected compounds and DHC. The obtained data revealed that five compounds had docking scores better than DHC (≥ -5.9 kcal/mol). Moreover, data from molecular mechanics and the Poisson - Boltzmann surface area (MM/PBSA) binding energy over 200 ns MD simulation confirmed that Cmd-1 and Cmd-4 exhibited higher stability with ΔGbinding of -40.8 and -49.1 kcal/mol, respectively, which is better than DHC (-35.1 kcal/mol). Finally, various energetic and structural studies showed the high stability of the two generated compounds within the active site of ERK-2. This study highlights the potential use of Cmd-1 and Cmd-4 as promising anti-ERK-2 drug candidates.Communicated by Ramaswamy H. Sarma.

Mechanism and application of feedback loops formed by mechanotransduction and histone modifications

Mechanical stimulation is the key physical factor in cell environment. Mechanotransduction acts as a fundamental regulator of cell behavior, regulating cell proliferation, differentiation, apoptosis, and exhibiting specific signature alterations during the pathological process. As research continues, the role of epigenetic science in mechanotransduction is attracting attention. However, the molecular mechanism of the synergistic effect between mechanotransduction and epigenetics in physiological and pathological processes has not been clarified. We focus on how histone modifications, as important components of epigenetics, are coordinated with multiple signaling pathways to control cell fate and disease progression. Specifically, we propose that histone modifications can form regulatory feedback loops with signaling pathways, that is, histone modifications can not only serve as downstream regulators of signaling pathways for target gene transcription but also provide feedback to regulate signaling pathways. Mechanotransduction and epigenetic changes could be potential markers and therapeutic targets in clinical practice.

The Role of Oxidative Stress in Hypomagnetic Field Effects

The geomagnetic field (GMF) is crucial for the survival and evolution of life on Earth. The weakening of the GMF, known as the hypomagnetic field (HMF), significantly affects various aspects of life on Earth. HMF has become a potential health risk for future deep space exploration. Oxidative stress is directly involved in the biological effects of HMF on animals or cells. Oxidative stress occurs when there is an imbalance favoring oxidants over antioxidants, resulting in cellular damage. Oxidative stress is a double-edged sword, depending on the degree of deviation from homeostasis. In this review, we summarize the important experimental findings from animal and cell studies on HMF exposure affecting intracellular reactive oxygen species (ROS), as well as the accompanying many physiological abnormalities, such as cognitive dysfunction, the imbalance of gut microbiota homeostasis, mood disorders, and osteoporosis. We discuss new insights into the molecular mechanisms underlying these HMF effects in the context of the signaling pathways related to ROS. Among them, mitochondria are considered to be the main organelles that respond to HMF-induced stress by regulating metabolism and ROS production in cells. In order to unravel the molecular mechanisms of HMF action, future studies need to consider the upstream and downstream pathways associated with ROS.

In vitro antiviral activity of eugenol on Singapore grouper iridovirus

The high mortality rate of Singapore grouper iridovirus (SGIV) posing a serious threat to the grouper aquaculture industry and causing significant economic losses. Therefore, finding effective drugs against SGIV is of great significance. Eugenol (C10H12O2) is a phenolic aromatic compound, has been widely studied for its anti-inflammatory, antioxidant and antiviral capacity. In this study, we explored the effect of eugenol on SGIV infection and its possible mechanisms using grouper spleen cells (GS) as an in vitro model. We found that treatment of GS cells with 100 μM eugenol for 4 h exhibited the optimal inhibitory effect on SGIV. Eugenol was able to reduce the expression level of inflammatory factors by inhibiting the activation of MAPK pathway and also inhibited the activity of NF-κB and AP-1 promoter. On the other hand, eugenol attenuated cellular oxidative stress by reducing intracellular ROS and promoted the expression of interferon-related genes. Therefore, we conclude that eugenol inhibits SGIV infection by enhancing cellular immunity through its anti-inflammatory and antioxidant functions.

Role of 14-3-3 protein family in the pathobiology of EBV in immortalized B cells and Alzheimer's disease

Background and Aims

Several studies have revealed that Epstein-Barr virus (EBV) infection raised the likelihood of developing Alzheimer's disease (AD) via infecting B lymphocytes. The purpose of the current investigation was to assess the possible association between EBV infection and AD.

Methods

The microarray datasets GSE49628, GSE126379, GSE122063, and GSE132903 were utilized to extract DEGs by using the GEO2R tool of the GEO platform. The STRING tool was used to determine the interaction between the DEGs, and Cytoscape was used to visualize the results. The DEGs that were found underwent function analysis, including pathway and GO, using the DAVID 2021 and ClueGo/CluePedia. By using MNC, MCC, Degree, and Radiality of cytoHubba, we identified seven common key genes. Gene co-expression analysis was performed through the GeneMANIA web tool. Furthermore, expression analysis of key genes was performed through GTEx software, which have been identified in various human brain regions. The miRNA-gene interaction was performed through the miRNet v 2.0 tool. DsigDB on the Enrichr platform was utilized to extract therapeutic drugs connected to key genes.

Results

In GEO2R analysis of datasets with |log2FC|≥ 0.5 and p-value <0.05, 8386, 10,434, 7408, and 759 genes were identified. A total of 141 common DEGs were identified by combining the extracted genes of different datasets. A total of 141 nodes and 207 edges were found during the PPI analysis. The DEG GO analysis with substantial alterations disclosed that they are associated to molecular functions and biological processes, such as positive regulation of neuron death, autophagy regulation of mitochondrion, response of cell to insulin stimulus, calcium signaling regulation, organelle transport along microtubules, protein kinase activity, and phosphoserine binding. Kyoto Encyclopedia of Genes and Genomes analysis discovered the correlation between the DEGs in pathways of neurodegeneration: multiple disease, cell cycle, and cGMP-PKG signaling pathway. Finally, YWHAH, YWHAG, YWHAB, YWHAZ, MAP2K1, PPP2CA, and TUBB genes were identified that are strongly linked to EBV and AD. Three miRNAs, i.e., hsa-mir-15a-5p, hsa-let-7a-5p, and hsa-mir-7-5p, were identified to regulate most of hub genes that are associated with EBV and AD. Further top 10 significant therapeutic drugs were predicted.

Conclusion

We have discovered new biomarkers and therapeutic targets for AD, as well as the possible biological mechanisms whereby infection with EBV may be involved in AD susceptibility for the first time.

Revealing the Mechanisms of Qilongtian Capsules in the Treatment of Chronic Obstructive Pulmonary Disease Based on Integrated Network Pharmacology, Molecular Docking, and In Vivo Experiments

The Qilongtian capsule (QLT) is a Chinese patent medicine that has been approved for the treatment of chronic obstructive pulmonary disease (COPD). However, the precise pharmacodynamic material basis and molecular mechanism have not been well illustrated. In this study, we identified the effect of QLT on COPD through a cigarette smoke extract (CSE)/lipopolysaccharide (LPS) induced COPD mice model. The absorption of blood components in QLT were identified using ultrahigh performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). Network pharmacology was used to predict the potential targets and therapeutic mechanisms of QLT, which were further validated using in vivo experiments and molecular docking. Pharmacodynamic studies revealed that QLT could ameliorate pulmonary function and pulmonary pathology, reduce collagen fiber accumulation, and attenuate inflammatory responses in mice with CSE/LPS induced COPD. A total of 21 components of QLT absorbed in the blood were detected. Network pharmacology analysis indicated that TNF, IL-6, EGFR, and AKT1 may be the core targets, mainly involving the MAPK signaling pathway. Besides, Sachaloside II, Ginsenoside Rh1, Ginsenoside F1, Rosiridin, and Ginsenoside Rf were the key compounds. Molecular docking results showed that the key components could spontaneously bind to EGFR and MAPK to form a relatively stable conformation. In vivo experiments revealed that QLT could suppress the activation of the EGFR/MAPK signaling pathway, thereby improving lung injury in mice with COPD. Overall, these findings provide evidence for the treatment of COPD with QLT.

Molecular Dynamics Simulation on the Suppression Mechanism of Phosphorylation to Ser222 by Allosteric Inhibitors Targeting MEK1/2 Kinase

Allosteric inhibitors of mitogen-activated protein kinase 1 (MEK1) reveal distinct interactions with MEK1 activation loop residues. The structural analyses will determine whether, and how, distinct inhibitors suppress the phosphorylation of MEK1 and may guide future therapeutic development. In this study, we explored the suppression mechanism of the phosphorylation process in the presence of MEK allosteric inhibitors, such as selumetinib, trametinib, cobimetinib, and CH5126766, by employing molecular dynamics simulations accompanied by principal component analysis. The simulations of wildtype MEK1 show that Ser222 can come close to γ-phosphate but not Ser218. We have found the conformation where Ser222 is within 5 Å of distance, which makes Ser222 accessible for γ-phosphate. The conformation analysis from the simulations of MEK1 in the presence of allosteric inhibitors reveals that the inhibitor restricts the flexibility of Ser222 through strong interactions with the activation loop, Lys97, and water mediates interactions with amino acids in the vicinity. The results reveal that all the inhibitors act as screeners between the activation loop and Mg-ATP and restricting the flexibility of the activation loop through strong interaction causes the suppression of the phosphorylation process of MEK1. The results conclude that a strong interaction of allosteric inhibitors with the activation loop restricts the movement of Ser222 toward Mg-ATP, which could be the dominant factor for the suppression of phosphorylation in MEK1. This research will provide novel insights to design effective anticancer therapeutics for targeting MEK1 in the future.

STAU1 exhibits a dual function by promoting amyloidogenesis and tau phosphorylation in cultured cells

Staufen-1 (STAU1) is a double-stranded RNA-binding protein (RBP) involved in a variety of pathological conditions. In this study, we investigated the potential role of STAU1 in Alzheimer's disease (AD), in which two hallmarks are well-established as cerebral β-amyloid protein (Aβ) deposition and Tau-centered neurofibrillary tangles. We found that STAU1 protein level was significantly increased in cells that stably express full-length APP and the brain of APP/PS1 mice, an animal model of AD. STAU1 knockdown, as opposed to overexpression, significantly decreased the protein levels of β-amyloid converting enzyme 1 (BACE1) and Aβ. We further found that STAU1 extended the half-life of the BACE1 mRNA through binding to the 3' untranslated region (3'UTR). Transcriptome analysis revealed that STAU1 enhanced the expression of growth arrest and DNA damage 45 β (GADD45B) upstream of P38 MAPK signaling, which contributed to STAU1-induced regulation of Tau phosphorylation at Ser396 and Thr181. Together, STAU1 promoted amyloidogenesis by inhibiting BACE1 mRNA decay, and augmented Tau phosphorylation through activating GADD45B in relation to P38 MAPK. Targeting STAU1 that acts on both amyloidogenesis and tauopathy may serve as an optimistic approach for AD treatment.

Rack1-mediated ferroptosis affects hindgut development in rats with anorectal malformations: Spatial transcriptome insights

Anorectal malformation (ARM), a common congenital anomaly of the digestive tract, is a result of insufficient elongation of the urorectal septum. The cytoplasmic protein Receptor of Activated C-Kinase 1 (Rack1) is involved in embryonic neural development; however, its role in embryonic digestive tract development and ARM formation is unexplored. Our study explored the hindgut development and cell death mechanisms in ARM-affected rats using spatial transcriptome analysis. We induced ARM in rats by administering ethylenethiourea via gavage on gestational day (GD) 10. On GDs 14-16, embryos from both normal and ARM groups underwent spatial transcriptome sequencing, which identified key genes and signalling pathways. Rack1 exhibited significant interactions among differentially expressed genes on GDs 15 and 16. Reduced Rack1 expression in the ARM-affected hindgut, verified by Rack1 silencing in intestinal epithelial cells, led to increased P38 phosphorylation and activation of the MAPK signalling pathway. The suppression of this pathway downregulated Nqo1 and Gpx4 expression, resulting in elevated intracellular levels of ferrous ions, reactive oxygen species (ROS) and lipid peroxides. Downregulation of Gpx4 expression in the ARM hindgut, coupled with Rack1 co-localisation and consistent mitochondrial morphology, indicated ferroptosis. In summary, Rack1, acting as a hub gene, modulates ferrous ions, lipid peroxides, and ROS via the P38-MAPK/Nqo1/Gpx4 axis. This modulation induces ferroptosis in intestinal epithelial cells, potentially influencing hindgut development during ARM onset.

Weighted gene co-expression network analysis reveals genes related to growth performance in Hu sheep

Hu sheep are a unique breed in our country with great reproductive potential, the extent of whose breeding has been steadily rising in recent years. The study subjects in this experiment were 8-month-old Hu sheep (n = 112). First of all, the growth performance, slaughter performance and meat quality of their eye muscle quality were assessed, meanwhile their live weight, carcass weight, body length, body height, chest circumference, chest depth and tube circumference were respectively 33.81 ± 5.47 kg, 17.43 ± 3.21 kg, 60.36 ± 4.41 cm, 63.25 ± 3.88 cm, 72.03 ± 5.02 cm, 30.70 ± 2.32 cm and 7.36 ± 0.56 cm, with a significant difference between rams and ewes (P < 0.01). Following that, transcriptome sequencing was done, and candidate genes related to growth performance were identified using the weighted co-expression network analysis (WGCNA) approach, which was used to identified 15 modules, with the turquoise and blue modules having the strongest association with growth and slaughter performance, respectively. We discovered hub genes such as ARHGAP31, EPS8, AKT3, EPN1, PACS2, KIF1C, C12H1orf115, FSTL1, PTGFRN and IFIH1 in the gene modules connected with growth and slaughter performance. Our research identifies the hub genes associated with the growth and slaughter performance of Hu sheep, which play an important role in their muscle growth, organ and cartilage development, blood vessel development and energy metabolic pathways. Our findings might lead to the development of potentially-useful biomarkers for the selection of growth and slaughterer performance-related attributes of sheep and other livestock.

A review of non-classical MAPK family member, MAPK4: A pivotal player in cancer development and therapeutic intervention

Mitogen-Activated Protein Kinases (MAPKs) are serine/threonine protein kinases that play a crucial role in transmitting extracellular signals to the intracellular environment, influencing a wide range of cellular processes including proliferation, differentiation, apoptosis, metabolic activities, immune function and stress response. MAPK4, a non-classical MAPK, is frequently overexpressed in various malignancies, including prostate, breast, cervix, thyroid, and gliomas. It orchestrates cell proliferation, migration, and apoptosis via the AKT/mTOR and/or PDK1 signaling pathways, thus facilitating tumor cell growth. Furthermore, MAPK4 expression is closely associated with the effectiveness of specific inhibitors like PI3K and PARP1, and also correlate with the survival rates of cancer patients. Increasing evidence highlights MAPK4's involvement in the tumor microenvironment, modulating immune response and inflammation-related diseases. This review comprehensively explores the structure, function, and oncogenic role of MAPK4, providing a deeper understanding of its activation and mechanisms of action in tumorigenesis, which might be helpful for the development of innovative therapeutic strategies for cancer management.

GLUT2 regulation of p38 MAPK isoform protein expression and p38 phosphorylation in male versus female rat hypothalamic primary astrocyte Cultures

Recent studies documented regulation of hypothalamic astrocyte mitogen-activated protein kinase (MAPK) pathways, including p38, by the plasma membrane glucose carrier/sensor glucose transporter-2 (GLUT2). Sex-specific GLUT2 control of p38 phosphorylation was observed, but effects on individual p38 family protein profiles were not investigated. Current research employed an established primary astrocyte culture model, gene knockdown tools, and selective primary antisera against p38-alpha, p38-beta, p38-gamma, and p38-delta isoforms to investigate whether GLUT2 governs expression of one or more of these variants in a glucose-dependent manner. Data show that GLUT2 inhibits baseline expression of each p38 protein in male cultures, yet stimulates p38-delta profiles without affecting other p38 proteins in female. Glucose starvation caused selective up-regulation of p38-delta profiles in male versus p38-alpha and -gamma proteins in female; these positive responses were amplified by GLUT2 siRNA pretreatment. GLUT2 opposes or enhances basal p38 phosphorylation in male versus female, respectively. GLUT2 siRNA pretreatment did not affect glucoprivic patterns of phospho-p38 protein expression in either sex. Outcomes document co-expression of the four principal p38 MAPK family proteins in hypothalamic astrocytes, and implicate GLUT2 in regulation of all (male) versus one (female) variant(s). Glucoprivation up-regulated expression of distinctive p38 isoforms in each sex; these stimulatory responses are evidently blunted by GLUT2. Glucoprivic-associated loss of GLUT2 gene silencing effects on p38 phosphorylation infers either that glucose status determines whether this sensor controls phosphorylation, or that decrements in screened glucose in each instance are of sufficient magnitude to abolish GLUT2 regulation of that function.

Pectinose induces cell cycle arrest in luminal A and triple-negative breast cancer cells by promoting autophagy through activation of the p38 MAPK signaling pathway

Breast cancer patients often have a poor prognosis largely due to lack of effective targeted therapy. It is now well established that monosaccharide enhances growth retardation and chemotherapy sensitivity in tumor cells. However, Pectinose whether has capability to restrict the proliferation of tumor cells remain unclear. Here, we report that Pectinose induced cytotoxicity is modulated by autophagy and p38 MAPK signaling pathway in breast cancer cell lines. The proliferation of cells was dramatically inhibited by Pectinose exposure in a dose-dependent manner, which was relevant to cell cycle arrest, as demonstrated by G2/M cell cycle restriction and ectopic expression of Cyclin A, Cyclin B, p21and p27. Mechanistically, we further identified that Pectinose is positively associated with autophagy and the activation of the p38 MAPK signaling in breast cancer. In contrast, 3-Ma or SB203580, the inhibitor of autophagy or p38 MAPK, reversed the efficacy of Pectinose suppressing on breast cancer cell lines proliferation and cell cycle process. Additionally, Pectinose in vivo treatment could significantly inhibit xenograft growth of breast cancer cells. Taken together, our findings were the first to reveal that Pectinose triggered cell cycle arrest by inducing autophagy through the activation of p38 MAPK signaling pathway in breast cancer cells,especially in luminal A and triple-negative breast cancer.

Human Dendritic Cell Maturation Is Modulated by Leishmania mexicana through Akt Signaling Pathway

Dendritic cells (DC) along with macrophages are the main host cells of the intracellular parasite Leishmania. DC traverse a process of maturation, passing through an immature state with phagocytic ability to a mature one where they can modulate the immune response through the secretion of cytokines. Several studies have demonstrated that Leishmania inhibits DC maturation. Nevertheless, when cells are subjected to a second stimulus such as LPS/IFN-γ, they manage to mature. In the maturation process of DC, several signaling pathways have been implicated, importantly MAPK. On the other hand, Akt is a signaling pathway deeply involved in cell survival. Some Leishmania species have shown to activate MAPK and Akt in different cells. The aim of this work was to investigate the role of ERK and Akt in the maturation of monocyte-derived DC (moDC) infected with L. mexicana. moDC were infected with L. mexicana metacyclic promastigotes, and the phosphorylation of ERK and Akt, the expression of MHCII and CD86 and IL-12 transcript, and secretion were determined in the presence or absence of an Akt inhibitor. We showed that L. mexicana induces a sustained Akt and ERK phosphorylation, while the Akt inhibitor inhibits it. Moreover, the infection of moDC downregulates CD86 expression but not MHCII, and the Akt inhibitor reestablishes CD86 expression and 12p40 production. Thus, L. mexicana can modulate DC maturation though Akt signaling.

D-arabinose induces cell cycle arrest by promoting autophagy via p38 MAPK signaling pathway in breast cancer

Breast cancer patients often have a poor prognosis largely due to lack of effective targeted therapy. It is now well established that monosaccharide enhances growth retardation and chemotherapy sensitivity in tumor cells. We investigated whether D-arabinose has capability to restrict the proliferation of tumor cells and its mechanism. Here, we report that D-arabinose induced cytotoxicity is modulated by autophagy and p38 MAPK signaling pathway in breast cancer cell lines. The proliferation of cells was evaluated by CCK-8 and Colony formation assay. The distribution of cells in cell cycle phases was analyzed by flow cytometry. Cell cycle, autophagy and MAPK signaling related proteins were detected by western blotting. Mouse xenograft model was used to evaluate the efficacy of D-arabinose in vivo. The proliferation of cells was dramatically inhibited by D-arabinose exposure in a dose-dependent manner, which was relevant to cell cycle arrest, as demonstrated by G2/M cell cycle restriction and ectopic expression of cell cycle related proteins. Mechanistically, we further identified that D-arabinose is positively associated with autophagy and the activation of the p38 MAPK signaling in breast cancer. In contrast, 3-Ma or SB203580, the inhibitor of autophagy or p38 MAPK, reversed the efficacy of D-arabinose. Additionally, D-arabinose in vivo treatment could significantly inhibit xenograft growth of breast cancer cells. Our findings were the first to reveal that D-arabinose triggered cell cycle arrest by inducing autophagy through the activation of p38 MAPK signaling pathway in breast cancer cells.

Progress in the development of ERK1/2 inhibitors for treating cancer and other diseases

The extracellular signal-regulated kinases-1 and 2 (ERK1/2) are ubiquitous regulators of many cellular functions, including proliferation, differentiation, migration, and cell death. ERK1/2 regulate cell functions by phosphorylating a diverse collection of protein substrates consisting of other kinases, transcription factors, structural proteins, and other regulatory proteins. ERK1/2 regulation of cell functions is tightly regulated through the balance between activating phosphorylation by upstream kinases and inactivating dephosphorylation by phosphatases. Disruption of homeostatic ERK1/2 regulation caused by elevated extracellular signals or mutations in upstream regulatory proteins leads to the constitutive activation of ERK1/2 signaling and uncontrolled cell proliferation observed in many types of cancer. Many inhibitors of upstream kinase regulators of ERK1/2 have been developed and are part of targeted therapeutic options to treat a variety of cancers. However, the efficacy of these drugs in providing sustained patient responses is limited by the development of acquired resistance often involving re-activation of ERK1/2. As such, recent drug discovery efforts have focused on the direct targeting of ERK1/2. Several ATP competitive ERK1/2 inhibitors have been identified and are being tested in cancer clinical trials. One drug, Ulixertinib (BVD-523), has received FDA approval for use in the Expanded Access Program for patients with no other therapeutic options. This review provides an update on ERK1/2 inhibitors in clinical trials, their successes and limitations, and new academic drug discovery efforts to modulate ERK1/2 signaling for treating cancer and other diseases.

An insight into crosstalk among multiple signalling pathways contributing to the pathophysiology of PTSD and depressive disorders

Post-traumatic stress disorder (PTSD) and depressive disorders represent two significant mental health challenges with substantial global prevalence. These are debilitating conditions characterized by persistent, often comorbid, symptoms that severely impact an individual's quality of life. Both PTSD and depressive disorders are often precipitated by exposure to traumatic events or chronic stress. The profound impact of PTSD and depressive disorders on individuals and society necessitates a comprehensive exploration of their shared and distinct pathophysiological features. Although the activation of the stress system is essential for maintaining homeostasis, the ability to recover from it after diminishing the threat stimulus is also equally important. However, little is known about the main reasons for individuals' differential susceptibility to external stressful stimuli. The solution to this question can be found by delving into the interplay of stress with the cognitive and emotional processing of traumatic incidents at the molecular level. Evidence suggests that dysregulation in these signalling cascades may contribute to the persistence and severity of PTSD and depressive symptoms. The treatment strategies available for this disorder are antidepressants, which have shown good efficiency in normalizing symptom severity; however, their efficacy is limited in most individuals. This calls for the exploration and development of innovative medications to address the treatment of PTSD. This review delves into the intricate crosstalk among multiple signalling pathways implicated in the development and manifestation of these mental health conditions. By unravelling the complexities of crosstalk among multiple signalling pathways, this review aims to contribute to the broader knowledge base, providing insights that could inform the development of targeted interventions for individuals grappling with the challenges of PTSD and depressive disorders.

Jun/Fos promotes migration and invasion of hepatocellular carcinoma cells by enhancing BORIS promoter activity

The Brother of the Regulator of Imprinted Sites (BORIS), as a specific indicator of hepatocellular carcinoma, exhibits a significant increase in expression. However, its upstream regulatory network remains enigmatic. Previous research has indicated a strong correlation between the Hippo pathway and the progression of hepatocellular carcinoma. It is well established that the Activator Protein-1 (AP-1) frequently engages in interactions with the Hippo pathway. Thus, we attempt to prove whether Jun and Fos, a major member of the AP-1 family, are involved in the regulation of BORIS expression. Bioinformatics analysis revealed the existence of binding sites for Jun and Fos within the BORIS promoter. Through a series of overexpression and knockdown experiments, we corroborated that Jun and Fos have the capacity to augment BORIS expression, thereby fostering the migration and invasion of hepatocellular carcinoma cells. Moreover, Methylation-Specific PCR and Bisulfite Sequencing PCR assays revealed that Jun and Fos do not have a significant impact on the demethylation of the BORIS promoter. However, luciferase reporter and chromatin immunoprecipitation experiments substantiated that Jun and Fos could directly bind to the BORIS promoter, thereby enhancing its transcription. In conclusion, these results suggest that Jun and Fos can promote the development of hepatocellular carcinoma by directly regulating the expression of BORIS. These findings may provide experimental evidence positioning BORIS as a novel target for the clinical intervention of hepatocellular carcinoma.

Progress in RAS-targeted therapeutic strategies: From small molecule inhibitors to proteolysis targeting chimeras

As a widely considerable target in chemical biology and pharmacological research, rat sarcoma (RAS) gene mutations play a critical driving factor in several fatal cancers. Despite the great progress of RAS subtype-specific inhibitors, rapid acquired drug resistance could limit their further clinical applications. Proteolysis targeting chimera (PROTAC) has emerged as a powerful tool to handle "undruggable" targets and exhibited significant therapeutic benefit for the combat of drug resistance. Owing to unique molecular mechanism and binding kinetics, PROTAC is expected to become a feasible strategy to break the bottleneck of classical RAS inhibitors. This review aims to discuss the current advances of RAS inhibitors and especially focus on PROTAC strategy targeting RAS mutations and their downstream effectors for relevant cancer treatment.

The Role of the Dysregulated JNK Signaling Pathway in the Pathogenesis of Human Diseases and Its Potential Therapeutic Strategies: A Comprehensive Review

JNK is named after c-Jun N-terminal kinase, as it is responsible for phosphorylating c-Jun. As a member of the mitogen-activated protein kinase (MAPK) family, JNK is also known as stress-activated kinase (SAPK) because it can be activated by extracellular stresses including growth factor, UV irradiation, and virus infection. Functionally, JNK regulates various cell behaviors such as cell differentiation, proliferation, survival, and metabolic reprogramming. Dysregulated JNK signaling contributes to several types of human diseases. Although the role of the JNK pathway in a single disease has been summarized in several previous publications, a comprehensive review of its role in multiple kinds of human diseases is missing. In this review, we begin by introducing the landmark discoveries, structures, tissue expression, and activation mechanisms of the JNK pathway. Next, we come to the focus of this work: a comprehensive summary of the role of the deregulated JNK pathway in multiple kinds of diseases. Beyond that, we also discuss the current strategies for targeting the JNK pathway for therapeutic intervention and summarize the application of JNK inhibitors as well as several challenges now faced. We expect that this review can provide a more comprehensive insight into the critical role of the JNK pathway in the pathogenesis of human diseases and hope that it also provides important clues for ameliorating disease conditions.

Streptococcus anginosus promotes gastric inflammation, atrophy, and tumorigenesis in mice

Streptococcus anginosus (S. anginosus) was enriched in the gastric mucosa of patients with gastric cancer (GC). Here, we show that S. anginosus colonized the mouse stomach and induced acute gastritis. S. anginosus infection spontaneously induced progressive chronic gastritis, parietal cell atrophy, mucinous metaplasia, and dysplasia in conventional mice, and the findings were confirmed in germ-free mice. In addition, S. anginosus accelerated GC progression in carcinogen-induced gastric tumorigenesis and YTN16 GC cell allografts. Consistently, S. anginosus disrupted gastric barrier function, promoted cell proliferation, and inhibited apoptosis. Mechanistically, we identified an S. anginosus surface protein, TMPC, that interacts with Annexin A2 (ANXA2) receptor on gastric epithelial cells. Interaction of TMPC with ANXA2 mediated attachment and colonization of S. anginosus and induced mitogen-activated protein kinase (MAPK) activation. ANXA2 knockout abrogated the induction of MAPK by S. anginosus. Thus, this study reveals S. anginosus as a pathogen that promotes gastric tumorigenesis via direct interactions with gastric epithelial cells in the TMPC-ANXA2-MAPK axis.

A prognostic marker LTBP1 is associated with epithelial mesenchymal transition and can promote the progression of gastric cancer

LTBP1 is closely related to TGF-β1 function as an essential component, which was unclear in gastric cancer (GC). Harbin Medical University (HMU)-GC cohort and The Cancer Genome Atlas (TCGA) dataset were combined to form a training cohort to calculate the connection between LTBP1 mRNA expression, prognosis and clinicopathological features. The training cohort was also used to verify the biological function of LTBP1 and its relationship with immune microenvironment and chemosensitivity. In the tissue microarrays (TMAs), immunohistochemical (IHC) staining was performed to observe LTBP1 protein expression. The correlation between LTBP1 protein expression level and prognosis was also analyzed, and a nomogram model was constructed. Western blotting (WB) was used in cell lines to assess LTBP1 expression. Transwell assays and CCK-8 were employed to assess LTBP1's biological roles. In compared to normal gastric tissues, LTBP1 expression was upregulated in GC tissues, and high expression was linked to a bad prognosis for GC patients. Based on a gene enrichment analysis, LTBP1 was primarily enriched in the TGF-β and EMT signaling pathways. Furthermore, high expression of LTBP1 in the tumor microenvironment was positively correlated with an immunosuppressive response. We also found that LTBP1 expression (p = 0.006) and metastatic lymph node ratio (p = 0.044) were independent prognostic risk factors for GC patients. The prognostic model combining LTBP1 expression and lymph node metastasis ratio reliably predicted the prognosis of GC patients. In vitro proliferation and invasion of MKN-45 GC cells were inhibited and their viability was decreased by LTBP1 knockout. LTBP1 plays an essential role in the development and progression of GC, and is a potential prognostic biomarker and therapeutic target for GC.

Tools for investigating O-GlcNAc in signaling and other fundamental biological pathways

Cells continuously fine-tune signaling pathway proteins to match nutrient and stress levels in their local environment by modifying intracellular proteins with O-linked N-acetylglucosamine (O-GlcNAc) sugars, an essential process for cell survival and growth. The small size of these monosaccharide modifications poses a challenge for functional determination, but the chemistry and biology communities have together created a collection of precision tools to study these dynamic sugars. This review presents the major themes by which O-GlcNAc influences signaling pathway proteins, including G-protein coupled receptors, growth factor signaling, mitogen-activated protein kinase (MAPK) pathways, lipid sensing, and cytokine signaling pathways. Along the way, we describe in detail key chemical biology tools that have been developed and applied to determine specific O-GlcNAc roles in these pathways. These tools include metabolic labeling, O-GlcNAc-enhancing RNA aptamers, fluorescent biosensors, proximity labeling tools, nanobody targeting tools, O-GlcNAc cycling inhibitors, light-activated systems, chemoenzymatic labeling, and nutrient reporter assays. An emergent feature of this signaling pathway meta-analysis is the intricate interplay between O-GlcNAc modifications across different signaling systems, underscoring the importance of O-GlcNAc in regulating cellular processes. We highlight the significance of O-GlcNAc in signaling and the role of chemical and biochemical tools in unraveling distinct glycobiological regulatory mechanisms. Collectively, our field has determined effective strategies to probe O-GlcNAc roles in biology. At the same time, this survey of what we do not yet know presents a clear roadmap for the field to use these powerful chemical tools to explore cross-pathway O-GlcNAc interactions in signaling and other major biological pathways.

Genetic alterations in thyroid cancer mediating both resistance to BRAF inhibition and anaplastic transformation

A subset of thyroid cancers present at advanced stage or with dedifferentiated histology and have limited response to standard therapy. Tumors harboring the BRAF V600E mutation may be treated with BRAF inhibitors; however, tumor response is often short lived due to multiple compensatory resistance mechanisms. One mode of resistance is the transition to an alternative cell state, which on rare occasions can correspond to tumor dedifferentiation. DNA sequencing and RNA expression profiling show that thyroid tumors that dedifferentiate after BRAF inhibition are enriched in known genetic alterations that mediate resistance to BRAF blockade, and may also drive tumor dedifferentiation, including mutations in the PI3K/AKT/MTOR (PIK3CA, MTOR), MAP/ERK (MET, NF2, NRAS, RASA1), SWI/SNF chromatin remodeling complex (ARID2, PBRM1), and JAK/STAT pathways (JAK1). Given these findings, recent investigations have evaluated the efficacy of dual-target therapies; however, continued lack of long-term tumor control illustrates the complex and multifactorial nature of these compensatory mechanisms. Transition to an immune-suppressed state is another correlate of BRAF inhibitor resistance and tumor dedifferentiation, suggesting a possible role for concurrent targeted therapy with immunotherapy. Investigations into combined targeted and immunotherapy are ongoing, but early results with checkpoint inhibitors, viral therapies, and CAR T-cells suggest enhanced anti-tumor immune activity with these combinations.

Resveratrol alleviates heat-stress-induced impairment of the jejunal mucosa through TLR4/MAPK signaling pathway in black-boned chicken

Heat stress in chickens caused by high temperatures in summer is a serious issue faced by the poultry industry globally, which reduces product quality. The aim of this study is to investigate the role of resveratrol in alleviating heat stress injury and inflammatory response of jejunal mucosa in black-boned chickens through TLR4/MAPK signaling pathway. In total, 240 black-boned chickens (28-day old) were randomly divided into 4 treatment groups as follows. The normal temperature (NT) and normal temperature with resveratrol (NT+Res) groups received a basal diet without and with 400 mg/kg resveratrol, respectively, and treated at 24℃ ± 2℃, 24 h/d. The high temperature (HT) and high temperature with resveratrol (HT+Res) groups received basal diet without and with 400 mg/kg resveratrol, respectively, and treated at 37℃ ± 2℃ for 8 h/d and 24°C ± 2°C for the rest of the time for 12 d. The results revealed the heat-stress responses impaired the villous structure of the jejunum, causing a rough and uneven surface of the jejunal villus, and local intestinal villi were even more prone to rupture. However, resveratrol significantly improved the morphology and structure of jejunal mucosa under heat stress. Heat stress increased the mRNA levels of toll-like receptor 4 (TLR4), c-Jun, c-fos, caspase-3, and p38 (P < 0.05), reduced mRNA level of Bcl-2, and reduced the expression of tight junction proteins Occludin, ZO-1, and Claudin1 (P < 0.05) in the jejunal mucosa. However, resveratrol inhibited the TLR4/ mitogen-activated protein kinase (MAPK) signaling pathway via downregulating TLR4, c-Jun, p38, and caspase-3 (P < 0.05); upregulating Bcl-2 (P < 0.05); decreasing the protein levels of MKK3, p53, and myeloid differentiation factor 88 (MYD88); and increasing the protein levels of Occludin, ZO-1, and Claudin1. In addition, it reduced the levels of JNK and p38 proteins (P < 0.05) and inflammatory factors like tumor necrosis factor-α (TNF-α) in the jejunal mucosa of black-boned chickens under heat stress. In conclusion, resveratrol may play a regulatory role in heat-stress-induced damage and inflammatory response in the intestinal mucosa of black-boned chickens under heat stress.

Unearthing Insights into Metabolic Syndrome by Linking Drugs, Targets, and Gene Expressions Using Similarity Measures and Graph Theory

AIMS AND OBJECTIVES

Metabolic syndrome (MetS) is a group of metabolic disorders that includes obesity in combination with at least any two of the following conditions, i.e., insulin resistance, high blood pressure, low HDL cholesterol, and high triglycerides level. Treatment of this syndrome is challenging because of the multiple interlinked factors that lead to increased risks of type-2 diabetes and cardiovascular diseases. This study aims to conduct extensive in silico analysis to (i) find central genes that play a pivotal role in MetS and (ii) propose suitable drugs for therapy. Our objective is to first create a drug-disease network and then identify novel genes in the drug-disease network with strong associations to drug targets, which can help in increasing the therapeutical effects of different drugs. In the future, these novel genes can be used to calculate drug synergy and propose new drugs for the effective treatment of MetS.

METHODS

For this purpose, we (i) investigated associated drugs and pathways for MetS, (ii) employed eight different similarity measures to construct eight gene regulatory networks, (iii) chose an optimal network, where a maximum number of drug targets were central, (iv) determined central genes exhibiting strong associations with these drug targets and associated disease-causing pathways, and lastly (v) employed these candidate genes to propose suitable drugs.

RESULTS

Our results indicated (i) a novel drug-disease network complex, with (ii) novel genes associated with MetS.

CONCLUSION

Our developed drug-disease network complex closely represents MetS with associated novel findings and markers for an improved understanding of the disease and suggested therapy.

Tanshinone IIA promotes the proliferation and differentiation ability of primary muscle stem cells via MAPK and Akt signaling

Salvia miltiorrhiza Bunge is a widely-used traditional Chinese medicine to treat a variety of diseases including muscle disorders. The underlying pharmacological mechanisms of which active component and how it functions are still unknown. Tanshinone IIA (Tan IIA) is the main active lipophilic compound in Salvia miltiorrhiza Bunge. Muscle stem cells (MuSCs) play a crucial role in maintaining healthy physiological function of skeletal muscle. For the purpose of this study, we investigated the effects of Tan IIA on primary MuSCs as well as mechanism. The EdU staining, cell counts assay and RT-qPCR results of proliferative genes revealed increased proliferation ability of MuSCs after Tan IIA treatment. Immunofluorescent staining of MyHC and RT-qPCR results of myogenic genes found Tan IIA contributed to promoting differentiation of MuSCs. In addition, enrichment analysis of RNA-seq data and Western blot assay results demonstrated activated MAPK and Akt signaling after treatment of Tan IIA during proliferation and differentiation. The above proliferative and differentiative phonotypes could be suppressed by the combination of MAPK inhibitor U0126 and Akt inhibitor Akti 1/2, respectively. Furthermore, HE staining found significantly improved myofiber regeneration of injured muscle after Tan IIA treatment, which also contributed to muscle force and running performance recovery. Thus, Tan IIA could promote proliferation and differentiation ability of MuSCs through activating MAPK and Akt signaling, respectively. These beneficial effects also significantly contributed to muscle regeneration and muscle function recovery after muscle injury.

Redox homeostasis dysregulation in noise-induced hearing loss: oxidative stress and antioxidant treatment

Noise exposure is an important cause of acquired hearing loss. Studies have found that noise exposure causes dysregulated redox homeostasis in cochlear tissue, which has been recognized as a signature feature of hearing loss. Oxidative stress plays a pivotal role in many diseases via very complex and diverse mechanisms and targets. Reactive oxygen species are products of oxidative stress that exert toxic effects on a variety of physiological activities and are considered significant in noise-induced hearing loss (NIHL). Endogenous cellular antioxidants can directly or indirectly counteract oxidative stress and regulate intracellular redox homeostasis, and exogenous antioxidants can complement and enhance this effect. Therefore, antioxidant therapy is considered a promising direction for NIHL treatment. However, drug experiments have been limited to animal models of NIHL, and these experiments and related observations are difficult to translate in humans; therefore, the mechanisms and true effects of these drugs need to be further analyzed. This review outlines the effects of oxidative stress in NIHL and discusses the main mechanisms and strategies of antioxidant treatment for NIHL.

BMAL1 inhibits renal fibrosis and renal interstitial inflammation by targeting the ERK1/2/ELK-1/Egr-1 axis

RATIONALE

Renal fibrosis and renal interstitial inflammation due to hydronephrosis are associated with progressive chronic kidney disease (CKD). The clock gene BMAL1 is thought to be involved in various diseases, including hypertension, diabetes, etc. However, little is known about how BMAL1 regulates renal fibrosis and renal interstitial inflammation in obstructed kidneys.

METHODS

The expression level of BMAL1 in UUO was examined using the GEO database. Lentivirus, siRNA and adeno-associated virus were used to modulate BMAL1 levels in HK-2 cells and mouse kidney. qRT-PCR, immunofluorescence staining, histological analysis, ELISA and Western blot were used to determine the level of fibrin deposition and the release of inflammatory factors. Immunofluorescence staining and western blotting were used to examine the interaction between BMAL1 and the ERK1/2/ELK-1/Egr-1 axis.

RESULTS

Bioinformatics analysis and in vivo experiments in this study showed that the expression level of BMAL1 in UUO model kidneys was higher than that in normal kidneys. We then found that downregulation of BMAL1 promoted the production of extracellular matrix (ECM) proteins and proinflammatory factors in vivo and in vitro, whereas upregulation inhibited this process. In addition, we demonstrated that the ERK1/2/ELK-1/Egr-1 axis is an important pathway for BMAL1 to play a regulatory role, and the use of PD98059 abolished the promoting effect of down-regulation of BMAL1 on fibrosis and inflammation.

CONCLUSIONS

Our findings suggest that BAML1 can target the ERK1/2/ELK-1/Egr-1 axis to suppress fibrotic progression and inflammatory events in obstructed kidneys, thereby inhibiting the development of CKD.

Associations of serum DNA methylation levels of chemokine signaling pathway genes with mild cognitive impairment (MCI) and Alzheimer's disease (AD)

OBJECTIVE

To investigate the associations of serum DNA methylation levels of chemokine signaling pathway genes with Alzheimer's disease (AD) and mild cognitive impairment (MCI) in elderly people in Xinjiang, China, and to screen out genes whose DNA methylation could distinguish AD and MCI.

MATERIALS AND METHODS

37 AD, 40 MCI and 80 controls were included in the present study. DNA methylation assay was done using quantitative methylation-specific polymerase chain reaction (qMSP). Genotyping was done using Sanger sequencing.

RESULTS

DNA methylation levels of ADCY2, MAP2K1 and AKT1 were significantly different among AD, MCI and controls. In the comparisons of each two groups, AKT1 and MAP2K1's methylation was both significantly different between AD and MCI (p < 0.05), whereas MAP2K1's methylation was also significantly different between MCI and controls. Therefore, AKT1's methylation was considered as the candidate serum marker to distinguish AD from MCI, and its association with AD was independent of APOE ε4 allele (p < 0.05). AKT1 hypermethylation was an independent risk factor for AD and MAP2K1 hypomethylation was an independent risk factor for MCI in logistic regression analysis (p < 0.05).

CONCLUSION

This study found that the serum of AKT1 hypermethylation is related to AD independently of APOE ε4, which was differentially expressed in the Entorhinal Cortex of the brain and was an independent risk factor for AD. It could be used as one of the candidate serum markers to distinguish AD and MCI. Serum of MAP2K1 hypomethylation is an independent risk factor for MCI.

Multiomics of HER2-low triple-negative breast cancer identifies a receptor tyrosine kinase-relevant subgroup with therapeutic prospects

To provide complementary information and reveal the molecular characteristics and therapeutic insights of HER2-low breast cancer, we performed this multiomics study of hormone receptor-negative (HR-) and HER2-low breast cancer, also known as HER2-low triple-negative breast cancer (TNBC), and identified 3 subgroups: basal-like, receptor tyrosine kinase-relevant (TKR), and mesenchymal stem-like. These 3 subgroups had distinct features and potential therapeutic targets and were validated in external data sets. Interestingly, the TKR subgroup (which exists in both HR+ and HR- breast cancer) had activated HER2 and downstream MAPK signaling. In vitro and in vivo patient-derived xenograft experiments revealed that pretreatment of the TKR subgroup with a tyrosine kinase inhibitor (lapatinib or tucatinib) could inhibit HER2 signaling and induce accumulated expression of nonfunctional HER2, resulting in increased sensitivity to the sequential HER2-targeting, Ab-drug conjugate DS-8201. Our findings identify clinically relevant subgroups and provide potential therapeutic strategies for HER2-low TNBC subtypes.

Integrated analysis of histone lysine lactylation (Kla)-specific genes suggests that NR6A1, OSBP2 and UNC119B are novel therapeutic targets for hepatocellular carcinoma

Histone lysine lactylation (Kla) plays a vital role in the tumorigenesis of hepatocellular carcinoma (HCC). Hence, we focused on Kla-specific genes to select novel therapeutic targets. Differentially expressed Kla-specific genes (DEKlaGs) were identified from TCGA with the cut-off criteria |log2(FlodChange (FC))| > 2, p-value < 0.05, following investigating the prognostic value. The correlation between lactate accumulation and prognostic DEKlaGs expression was further investigated. On the other hand, we explored the roles of Kla activation in the immune microenvironment, immunotherapy, and drug resistance. We conducted gene set enrichment analysis (GSEA) to predict the pathways influenced by Kla. The predictive power of Cox model was further identified in ICGC and GEO databases. A total of 129 DEKlaGs were identified, and 32 molecules might be potential prognostic biomarkers. A Cox model including ARHGEF37, MTFR2, NR6A1, NT5DC2, OSBP2, RNASEH2A, SFN, and UNC119B was constructed, which suggested unfavorable overall survival in high-risk score group, and risk score could serve as an indicator for large tumor size, poor pathological grade and advanced stage. NR6A1, OSBP2 and UNC119B could inhibit NK cell as well as TIL cell infiltration, and impair Type-I and II IFN responses in HCC, thereby contributing to unsatisfactory prognosis and immunotherapy resistance. OSBP2 and UNC119B were identified to be related to chemotherapy resistance. GSEA showed that WNT, MTOR, MAPK and NOTCH signaling pathways were activated, indicating that these pathways might play a crucial role during the Kla process. On the other hand, we showed that NR6A1 and OSBP2 were overexpressed in GEO. OSBP2 and UNC119B contributed to poor survival and advanced stage in ICGC. In summary, histone Kla was related to HCC prognosis and might serve as an independent biomarker. NR6A1, OSBP2 and UNC119B were associated with the prognosis, immunotherapy, and chemotherapy resistance, suggesting that NR6A1, OSBP2 and UNC119B might be novel candidate therapeutic targets for HCC.

Comprehensive analysis of crystal structure, spectroscopic properties, quantum chemical insights, and molecular docking studies of two pyrazolopyridine compounds: potential anticancer agents

In this study, two pyrazolo[3,4-b]pyridine derivatives (4a and 4b) were grown using a slow evaporation solution growth technique and characterized by FT-IR, HRMS, 1H/13C NMR spectroscopy, and X-ray crystallography. The 4a and 4b structures crystallized in monoclinic and triclinic systems with space groups P21/n and P1̄, respectively. Theoretical calculations were performed at the DFT/B3LYP level for the optimized geometries. The results were in excellent agreement with the experimental data (spectroscopic and XRD). This investigation encompasses molecular modeling studies including Hirshfeld surface analysis, energy framework calculations, and frontier molecular orbital analysis. Intermolecular interactions within the crystal structures of the compounds were explored through Hirshfeld surface analysis, which revealed the notable presence of hydrogen bonding and hydrophobic interactions. This insight provides valuable information on the structural stability and potential solubility characteristics of these compounds. The research was extended to docking analysis with eight distinct kinases (BRAF, HER2, CSF1R, MEK2, PDGFRA, JAK, AKT1, and AKT2). The results of this analysis demonstrate that both 4a and 4b interact effectively with the kinase-binding sites through a combination of hydrophobic interactions and hydrogen bonding. Compound 4a had the best affinity for proteins; this is related to the fact that the compound is not rigid and has a small size, allowing it to sit well at any binding site. This study contributes to the advancement of kinase inhibitor research and offers potential avenues for the development of new therapeutic agents for cancer treatment.

Prolonged Inhibition of the MEK1/2-ERK Signaling Axis Primes Interleukin-1 Beta Expression through Histone 3 Lysine 9 Demethylation in Murine Macrophages

Macrophages undergo different cellular states upon activation that can be hyporesponsive (tolerated) or hyperresponsive (primed or trained) to subsequent stimuli. Epigenetic modifications are known to play key roles in determining these cellular states. However, little is known about the role of signaling pathways that lead to these epigenetic modifications. Here, we examined the effects of various inhibitors targeting key signaling pathways induced by lipopolysaccharide (LPS) on tolerance and priming in murine macrophages. We found that a prolonged inhibition (>18 h) of the mitogen-activated protein kinase (MEK)1/2-extracellular signal-regulated kinase (ERK)1/2 signaling axis reversed tolerance and primed cells in expressing interleukin (IL)-1β and other inflammatory cytokines such as IL-6, tumor necrosis factor (TNF)α, and CXCL10. The ectopic expression of catalytically active and inactive MEK1 mutants suppressed and enhanced IL-1β expression, respectively. A transcriptomic analysis showed that cells primed by the MEK1/2 inhibitor U0126 expressed higher levels of gene sets associated with immune responses and cytokine/chemokine production, but expressed lower levels of genes with cell cycle progression, chromosome organization, and heterochromatin formation than non-primed cells. Of interest, the mRNA expressions of the histone 3 lysine 9 (H3K9) methyltransferase Suv39h1 and the H3K9 methylation reader Cbx5 were substantially suppressed, whereas the H3K9 demethylase Kdm7a was enhanced, suggesting a role of the MEK1/2-ERK signaling axis in H3K9 demethylation. The H3K9 trimethylation levels in the genomic regions of IL-1β, TNFα, and CXCL10 were decreased by U0126. Also, the H3K9 methyltransferase inhibitor BIX01294 mimicked the U0126 training effects and the overexpression of chromobox homolog (CBX)5 prevented the U0126 training effects in both RAW264.7 cells and bone-marrow-derived macrophages. Collectively, these data suggest that the prolonged inhibition of the MEK1/2-ERK signaling axis reverses tolerance and primed macrophages likely through decreasing the H3K9 methylation levels.

Public RNA-seq data-based identification and functional analyses reveal that MXRA5 retains proliferative and migratory abilities of dental pulp stem cells

Dental pulp stem cells (DPSC) usually remain quiescent in the dental pulp tissue; however, once the dental pulp tissue is injured, DPSCs potently proliferate and migrate into the injury microenvironment and contribute to immuno-modulation and tissue repair. However, the key molecules that physiologically support the potent proliferation and migration of DPSCs have not been revealed. In this study, we searched publicly available transcriptome raw data sets, which contain comparable (i.e., equivalently cultured) DPSC and mesenchymal stem cell data. Three data sets were extracted from the Gene Expression Omnibus database and then processed and analyzed. MXRA5 was identified as the predominant DPSC-enriched gene associated with the extracellular matrix. MXRA5 is detected in human dental pulp tissues. Loss of MXRA5 drastically decreases the proliferation and migration of DSPCs, concomitantly with reduced expression of the genes associated with the cell cycle and microtubules. In addition to the known full-length isoform of MXRA5, a novel splice variant of MXRA5 was cloned in DPSCs. Recombinant MXRA5 coded by the novel splice variant potently induced the haptotaxis migration of DPSCs, which was inhibited by microtubule inhibitors. Collectively, MXRA5 is a key extracellular matrix protein in dental pulp tissue for maintaining the proliferation and migration of DPSCs.

Inflammation-related signaling pathways in tendinopathy

Tendon is a connective tissue that produces movement by transmitting the force produced by muscle contraction to the bones. Most tendinopathy is caused by prolonged overloading of the tendon, leading to degenerative disease of the tendon. When overloaded, the oxygen demand of tenocytes increases, and the tendon structure is special and lacks blood supply, which makes it easier to form an oxygen-deficient environment in tenocytes. The production of reactive oxygen species due to hypoxia causes elevation of inflammatory markers in the tendon, including PGE2, IL-1β, and TNF-α. In the process of tendon healing, inflammation is also a necessary stage. The inflammatory environment formed by cytokines and various immune cells play an important role in the clearance of necrotic material, the proliferation of tenocytes, and the production of collagen fibers. However, excessive inflammation can lead to tendon adhesions and hinder tendon healing. Some important and diverse biological functions of the body originate from intercellular signal transduction, among which cytokine mediation is an important way of signal transduction. In particular, NF-κB, NLRP3, p38/MAPK, and signal transducer and activator of transcription 3, four common signaling pathways in tendinopathy inflammatory response, play a crucial role in the regulation and transcription of inflammatory factors. Therefore, summarizing the specific mechanisms of inflammatory signaling pathways in tendinopathy is of great significance for an in-depth understanding of the inflammatory response process and exploring how to inhibit the harmful part of the inflammatory response and promote the beneficial part to improve the healing effect of the tendon.

JNK Cascade-Induced Apoptosis-A Unique Role in GqPCR Signaling

The response of cells to extracellular signals is mediated by a variety of intracellular signaling pathways that determine stimulus-dependent cell fates. One such pathway is the cJun-N-terminal Kinase (JNK) cascade, which is mainly involved in stress-related processes. The cascade transmits its signals via a sequential activation of protein kinases, organized into three to five tiers. Proper regulation is essential for securing a proper cell fate after stimulation, and the mechanisms that regulate this cascade may involve the following: (1) Activatory or inhibitory phosphorylations, which induce or abolish signal transmission. (2) Regulatory dephosphorylation by various phosphatases. (3) Scaffold proteins that bring distinct components of the cascade in close proximity to each other. (4) Dynamic change of subcellular localization of the cascade's components. (5) Degradation of some of the components. In this review, we cover these regulatory mechanisms and emphasize the mechanism by which the JNK cascade transmits apoptotic signals. We also describe the newly discovered PP2A switch, which is an important mechanism for JNK activation that induces apoptosis downstream of the Gq protein coupled receptors. Since the JNK cascade is involved in many cellular processes that determine cell fate, addressing its regulatory mechanisms might reveal new ways to treat JNK-dependent pathologies.

Mitogen-Activated Protein Kinases (MAPKs) and Enteric Bacterial Pathogens: A Complex Interplay

Diverse extracellular and intracellular cues activate mammalian mitogen-activated protein kinases (MAPKs). Canonically, the activation starts at cell surface receptors and continues via intracellular MAPK components, acting in the host cell nucleus as activators of transcriptional programs to regulate various cellular activities, including proinflammatory responses against bacterial pathogens. For instance, binding host pattern recognition receptors (PRRs) on the surface of intestinal epithelial cells to bacterial pathogen external components trigger the MAPK/NF-κB signaling cascade, eliciting cytokine production. This results in an innate immune response that can eliminate the bacterial pathogen. However, enteric bacterial pathogens evolved sophisticated mechanisms that interfere with such a response by delivering virulent proteins, termed effectors, and toxins into the host cells. These proteins act in numerous ways to inactivate or activate critical components of the MAPK signaling cascades and innate immunity. The consequence of such activities could lead to successful bacterial colonization, dissemination, and pathogenicity. This article will review enteric bacterial pathogens' strategies to modulate MAPKs and host responses. It will also discuss findings attempting to develop anti-microbial treatments by targeting MAPKs.

MiR-23a Regulates Skin Langerhans Cell Phagocytosis and Inflammation-Induced Langerhans Cell Repopulation

Langerhans cells (LCs) are skin-resident macrophage that act similarly to dendritic cells for controlling adaptive immunity and immune tolerance in the skin, and they are key players in the development of numerous skin diseases. While TGF-β and related downstream signaling pathways are known to control numerous aspects of LC biology, little is known about the epigenetic signals that coordinate cell signaling during LC ontogeny, maintenance, and function. Our previous studies in a total miRNA deletion mouse model showed that miRNAs are critically involved in embryonic LC development and postnatal LC homeostasis; however, the specific miRNA(s) that regulate LCs remain unknown. miR-23a is the first member of the miR-23a-27a-24-2 cluster, a direct downstream target of PU.1 and TGF-b, which regulate the determination of myeloid versus lymphoid fates. Therefore, we used a myeloid-specific miR-23a deletion mouse model to explore whether and how miR-23a affects LC ontogeny and function in the skin. We observed the indispensable role of miR-23a in LC antigen uptake and inflammation-induced LC epidermal repopulation; however, embryonic LC development and postnatal homeostasis were not affected by cells lacking miR23a. Our results suggest that miR-23a controls LC phagocytosis by targeting molecules that regulate efferocytosis and endocytosis, whereas miR-23a promotes homeostasis in bone marrow-derived LCs that repopulate the skin after inflammatory insult by targeting Fas and Bcl-2 family proapoptotic molecules. Collectively, the context-dependent regulatory role of miR-23a in LCs represents an extra-epigenetic layer that incorporates TGF-b- and PU.1-mediated regulation during steady-state and inflammation-induced repopulation.