Activation of the JNK signaling pathway: breaking the brake on apoptosis

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.

Protective effect of Tat fused HPCA protein on neuronal cell death caused by ischemic injury

Background

Bain ischemia is a disease that occurs for various reasons, induces reactive oxygen species (ROS), and causes fatal damage to the nervous system. Protective effect of HPCA on ischemic injury has not been extensively studied despite its significance in regulating calcium homeostasis and promoting neuronal survival in CA1 region of the brain.

Objective

We investigate the role of HPCA in ischemic injury using a cell-permeable Tat peptide fused HPCA protein (Tat-HPCA).

Methods

Western blot analysis determined the penetration of Tat-HPCA into HT-22 cells and apoptotic signaling pathways. 5-CFDA, AM, DCF-DA, and TUNEL staining confirmed intracellular ROS production and DNA damage. The intracellular Ca2+ was measured in primary cultured neurons treated with H2O2. Protective effects were examined using immunohistochemistry and cognitive function tests by passive avoidance test and 8-arm radial maze test.

Results

Tat-HPCA effectively penetrated into HT-22 cells and inhibited H2O2-induced apoptosis, oxidative stress, and DNA fragmentation. It also effectively inhibited phosphorylation of JNK and regulated the activation of Caspase, Bax, Bcl-2, and PARP, leading to inhibition of apoptosis. Moreover, Ca2+ concentration decreased in cells treated with Tat-HPCA in primary cultured neurons. In an animal model of ischemia, Tat-HPCA effectively penetrated the hippocampus, inhibited cell death, and regulated activities of astrocytes and microglia. Additionally, Cognitive function tests show that Tat-HPCA improves neurobehavioral outcomes after cerebral ischemic injury.

Conclusion

These results suggest that Tat-HPCA might have potential as a therapeutic agent for treating oxidative stress-related diseases induced by ischemic injury, including ischemia.

Cadmium-induced Carcinogenesis in Respiratory Organs and the Prostate: Insights from Three Perspectives on Toxicogenomic Approach

Cadmium (Cd) exposure primarily occurs through inhalation, either by smoking or occupational exposure to contaminated air. Upon inhalation, Cd ultimately reaches the prostate through the bloodstream. In this review, we investigate the carcinogenic potential of Cd in both respiratory organs and the prostate. Specifically, this review examines cellular metabolism, comprehensive toxicity, and carcinogenic mechanisms by exploring gene ontology, biological networks, and adverse outcome pathways. In the respiratory organs, Cd induces lung cancer by altering the expression of IL1B and FGF2, causing DNA damage, reducing cell junction integrity, and promoting apoptosis. In the prostate, Cd induces prostate cancer by modifying the expression of EDN1 and HMOX1, leading to abnormal protein activities and maturation, suppressing tumor suppressors, and inducing apoptosis. Collectively, this review provides a comprehensive understanding of the carcinogenic mechanisms of Cd in two different organs by adopting toxicogenomic approaches. These insights can serve as a foundation for further research on cadmium-induced cancer, contributing to the establishment of future cancer prevention strategies.

Empagliflozin treatment of cardiotoxicity: A comprehensive review of clinical, immunobiological, neuroimmune, and therapeutic implications

Cancer and cardiovascular disorders are known as the two main leading causes of mortality worldwide. Cardiotoxicity is a critical and common adverse effect of cancer-related chemotherapy. Chemotherapy-induced cardiotoxicity has been associated with various cancer treatments, such as anthracyclines, immune checkpoint inhibitors, and kinase inhibitors. Different methods have been reported for the management of chemotherapy-induced cardiotoxicity. In this regard, sodium-glucose cotransporter-2 inhibitors (SGLT2i), a class of antidiabetic agents, have recently been applied to manage heart failure patients. Further, SGLT2i drugs such as EMPA exert protective cardiac and systemic effects. Moreover, it can reduce inflammation through the mediation of major inflammatory components, such as Nucleotide-binding domain-like receptor protein 3 (NLRP3) inflammasomes, Adenosine 5'-monophosphate-activated protein kinase (AMPK), and c-Jun N-terminal kinase (JNK) pathways, Signal transducer and activator of transcription (STAT), and overall decreasing transcription of proinflammatory cytokines. The clinical outcome of EMPA administration is related to improving cardiovascular risk factors, including body weight, lipid profile, blood pressure, and arterial stiffness. Intriguingly, SGLT2 suppressors can regulate microglia-driven hyperinflammation affecting neurological and cardiovascular disorders. In this review, we discuss the protective effects of EMPA in chemotherapy-induced cardiotoxicity from molecular, immunological, and neuroimmunological aspects to preclinical and clinical outcomes.

Donor Heart Preservation: Current Knowledge and the New Era of Machine Perfusion

Heart transplantation remains the conventional treatment in end-stage heart failure, with static cold storage (SCS) being the standard technique used for donor preservation. Nevertheless, prolonged cold ischemic storage is associated with the increased risk of early graft dysfunction attributed to residual ischemia, reperfusion, and rewarming damage. In addition, the demand for the use of marginal grafts requires the development of new methods for organ preservation and repair. In this review, we focus on current knowledge and novel methods of donor preservation in heart transplantation. Hypothermic or normothermic machine perfusion may be a promising novel method of donor preservation based on the administration of cardioprotective agents. Machine perfusion seems to be comparable to cold cardioplegia regarding donor preservation and allows potential repair treatments to be employed and the assessment of graft function before implantation. It is also a promising platform for using marginal organs and increasing donor pool. New pharmacological cardiac repair treatments, as well as cardioprotective interventions have emerged and could allow for the optimization of this modality, making it more practical and cost-effective for the real world of transplantation. Recently, the use of triiodothyronine during normothermic perfusion has shown a favorable profile on cardiac function and microvascular dysfunction, likely by suppressing pro-apoptotic signaling and increasing the expression of cardioprotective molecules.

Transcriptomics and interactomics during the primary infection of an SfNPV baculovirus on Spodoptera frugiperda larvae

The fall armyworm (FAW), Spodoptera frugiperda, has been the most devastating pest of corn as well as of other crops in America, and more recently in Africa and Asia. The development of resistance to chemical insecticides led the search for environmentally friendly biological alternatives such as baculoviruses. This study focuses on the primary infection of the baculovirus SfNPV-Ar in the FAW's midgut epithelium, by analyzing the differential expression of transcripts in excised midguts at 6, 12, and 24 h post-infection (hpi), and predicted their interactions. Interaction of viral factors with the infected midgut tissue could alters various cellular processes, such as the apoptotic system due to the up-regulation observed of FABP at 6 hpi and of HSP90 at 24 hpi, along with the down-regulated PRX at 6 hpi and FABP transcripts between 12 and 24 hpi. Changes in transcript regulation could affect the cellular architecture of infected cells due to up-regulation of ARP 2/3 at 6 and 12 hpi, followed by down-regulation at 24 hpi. In relation to protein folding proteins, HSP90 was up-regulated at 24 hpi and PDI was down-regulated between 6 and 12 hpi. With respect to metabolism and cellular transport, AcilBP and ATPS0 were up regulated at 6 hpi and 12 hpi, respectively. In reference to transcription and translation up-regulation of RPL11 at 6 hpi and of FPN32 and RPL19 at 24 hpi was detected, as well as the down-regulation of RPL19 at 6 hpi, of PDI and RPL7 at 12 hpi, and of FABP at 24 hpi. In conclusion, gene regulation induced by viral infection could be related to the cytoskeleton and cellular metabolism as well as to oxidative stress, apoptosis, protein folding, translation, and ribosomal structure. The results presented in this work are an approach to understanding how the virus takes control of the general metabolism of the insect host during the primary infection period.

Synergistic Effects of Radiotherapy With JNK Inhibitor-Incorporated Nanoparticle in an Intracranial Lewis Lung Carcinoma Mouse Models

BACKGROUND

Radiosurgery has been recognized as a reasonable treatment for metastatic brain tumors. Increasing the radiosensitivity and synergistic effects are possible ways to improve the therapeutic efficacy of specific regions of tumors. c-Jun-N-terminal kinase (JNK) signaling regulates H2AX phosphorylation to repair radiation-induced DNA breakage. We previously showed that blocking JNK signaling influenced radiosensitivity in vitro and in an in vivo mouse tumor model. Drugs can be incorporated into nanoparticles to produce a slow-release effect. This study assessed JNK radiosensitivity following the slow release of the JNK inhibitor SP600125 from a poly (DL-lactide-co-glycolide) (LGEsese) block copolymer in a brain tumor model.

MATERIALS AND METHODS

A LGEsese block copolymer was synthesized to fabricate SP600125-incorporated nanoparticles by nanoprecipitation and dialysis methods. The chemical structure of the LGEsese block copolymer was confirmed by 1H nuclear magnetic resonance (NMR) spectroscopy. The physicochemical and morphological properties were observed by transmission electron microscopy (TEM) imaging and measured with particle size analyzer. The blood-brain barrier (BBB) permeability to the JNK inhibitor was estimated by BBBflammaTM 440-dye-labeled SP600125. The effects of the JNK inhibitor were investigated using SP600125-incorporated nanoparticles and by optical bioluminescence, magnetic resonance imaging (MRI), and a survival assay in a mouse brain tumor model for Lewis lung cancer (LLC)-Fluc cells. DNA damage was estimated by histone γ H2AX expression and apoptosis was assessed by the immunohistochemical examination of cleaved caspase 3.

RESULTS

The SP600125-incorporated nanoparticles of the LGEsese block copolymer were spherical and released SP600125 continuously for 24h. The use of BBBflammaTM 440-dye-labeled SP600125 demonstrated the ability of SP600125 to cross the BBB. The blockade of JNK signaling with SP600125-incorporated nanoparticles significantly delayed mouse brain tumor growth and prolonged mouse survival after radiotherapy. γ H2AX, which mediates DNA repair protein, was reduced and the apoptotic protein cleaved-caspase 3 was increased by the combination of radiation and SP600125-incorporated nanoparticles.

Electroacupuncture inhibits hippocampal neuronal apoptosis and improves cognitive dysfunction in mice with vascular dementia via the JNK signaling pathway

BACKGROUND

Electroacupuncture (EA) has been shown to reduce cognitive impairment in vascular dementia (VaD) patients. However, the mechanism of action remains unknown.

OBJECTIVE

The c-Jun N-terminal kinase (JNK) signaling pathway plays an important role in apoptosis. Herein, we focused on whether EA can inhibit apoptosis and alleviate cognitive impairment by regulating the JNK signaling pathway using a mouse model of VaD induced by modified bilateral common carotid artery occlusion (BCCAo).

METHODS

In experiment I, 60 mice were randomly divided into a Sham group, BCCAo group, BCCAo + EA group, BCCAo + Sham-EA group, BCCAo + SP group (receiving the selective JNK inhibitor SP600125) and BCCAo + SP + EA group. Morris water maze tests, TdT-mediated dUTP-biotin nick end labeling (TUNEL) staining and flow cytometry were used to evaluate the effect of the EA intervention on VaD. In experiment II, 30 mice were randomly divided into a Sham group, BCCAo group, BCCAo + EA group, BCCAo + SP group and BCCAo + SP + EA group. Western blotting and real-time reverse transcription polymerase chain reaction were used to detect protein and mRNA expression of key factors in the JNK signaling pathway in the hippocampus.

RESULTS

EA, SP600125 and EA + SP600125 significantly inhibited hippocampal apoptosis and improved cognitive impairment in VaD model mice. There were no significant differences between the BCCAo group and the BCCAo + Sham-EA group. EA, EA + SP600125 and SP600125 inhibited the phosphorylation of JNK and caspase-3. EA and EA + SP600125 promoted protein and mRNA expression of B-cell lymphoma 2 (Bcl-2) in the hippocampus of VaD mice and inhibited protein and mRNA expression of activator protein (AP)-1, p53 and Bax.

CONCLUSION

EA can reverse cognitive deficits and inhibit hippocampal neuronal apoptosis in VaD model mice, at least partially through inhibition of the JNK signaling pathway and regulation of apoptosis signals.

Amino Acid Composition of a Chum Salmon (Oncorhynchus keta) Skin Gelatin Hydrolysate and Its Antiapoptotic Effects on Etoposide-Induced Osteoblasts

A gelatin hydrolysate with a hydrolysis degree of 13.7% was generated using the skin gelatin of chum salmon (Oncorhynchus keta) and papain-catalyzed enzymatic hydrolysis. The results of analysis demonstrated that four amino acids, namely Ala, Gly, Pro, and 4-Hyp, were the most abundant in the obtained gelatin hydrolysate with measured molar percentages ranging from 7.2% to 35.4%; more importantly, the four amino acids accounted for 2/3 of the total measured amino acids. However, two amino acids, Cys and Tyr, were not detected in the generated gelatin hydrolysate. The experimental results indicated that the gelatin hydrolysate at a dose of 50 µg/mL could combat etoposide-induced apoptosis in human fetal osteoblasts (hFOB 1.19 cells), causing a decrease in the total apoptotic cells from 31.6% to 13.6% (via apoptotic prevention) or 13.3% to 11.8% (via apoptotic reversal). Meanwhile, the osteoblasts exposed to the gelatin hydrolysate showed expression changes for 157 genes (expression folds > 1.5-fold), among which JNKK, JNK1, and JNK3 were from the JNK family with a 1.5-2.7-fold downregulated expression. Furthermore, the protein expressions of JNKK, JNK1, JNK3, and Bax in the treated osteoblasts showed a 1.25-1.41 fold down-regulation, whereas JNK2 expression was not detected in the osteoblasts. It is thus suggested that gelatin hydrolysate is rich in the four amino acids and has an in vitro antiapoptotic effect on etoposide-stimulated osteoblasts via mitochondrial-mediated JNKK/JNK(1,3)/Bax downregulation.

Innovative Thiosemicarbazones that Induce Multi-Modal Mechanisms to Down-Regulate Estrogen-, Progesterone-, Androgen- and Prolactin-Receptors in Breast Cancer

The estrogen receptor-α (ER-α) is a key driver of breast cancer (BC) and the ER-antagonist, tamoxifen, is a central pillar of BC treatment. However, cross-talk between ER-α, other hormone and growth factor receptors enables development of de novo resistance to tamoxifen. Herein, we mechanistically dissect the activity of a new class of anti-cancer agents that inhibit multiple growth factor receptors and down-stream signaling for the treatment of ER-positive BC. Using RNA sequencing and comprehensive protein expression analysis, we examined the activity of di-2-pyridylketone-4,4-dimethyl-3-thiosemicarbazone (Dp44mT) and di-2-pyridylketone-4-cyclohexyl-4-methyl-3-thiosemicarbazone (DpC), on the expression and activation of hormone and growth factor receptors, co-factors, and key resistance pathways in ER-α-positive BC. DpC differentially regulated 106 estrogen-response genes, and this was linked to decreased mRNA levels of 4 central hormone receptors involved in BC pathogenesis, namely ER, progesterone receptor (PR), androgen receptor (AR), and prolactin receptor (PRL-R). Mechanistic investigation demonstrated that due to DpC and Dp44mT binding metal ions, these agents caused a pronounced decrease in ER-α, AR, PR, and PRL-R protein expression. DpC and Dp44mT also inhibited activation and down-stream signaling of the epidermal growth factor (EGF) family receptors, and expression of co-factors that promote ER-α transcriptional activity, including SRC3, NF-κB p65, and SP1. In vivo, DpC was highly tolerable and effectively inhibited ER-α-positive BC growth. Through bespoke, non-hormonal, multi-modal mechanisms, Dp44mT and DpC decrease the expression of PR, AR, PRL-R, and tyrosine kinases that act with ER-α to promote BC, constituting an innovative therapeutic approach.

Discovery of Pyrimidine- and Coumarin-Linked Hybrid Molecules as Inducers of JNK Phosphorylation through ROS Generation in Breast Cancer Cells

Human epidermal growth factor receptor 2 (HER2)-positive breast cancer exhibits early relapses, poor prognoses, and high recurrence rates. Herein, a JNK-targeting compound has been developed that may be of utility in HER2-positive mammary carcinoma. The design of a pyrimidine-and coumarin-linked structure targeting JNK was explored and the lead structure PC-12 [4-(3-((2-((4-chlorobenzyl)thio) pyrimidin-4-yl)oxy)propoxy)-6-fluoro-2H-chromen-2-one (5d)] was observed to selectively inhibit the proliferation of HER2-positive BC cells. The compound PC-12 exerted DNA damage and induced apoptosis in HER-2 positive BC cells more significantly compared to HER-2 negative BC cells. PC-12 induced PARP cleavage and down-regulated the expression of IAP-1, BCL-2, SURVIVIN, and CYCLIN D1 in BC cells. In silico and theoretical calculations showed that PC-12 could interact with JNK, and in vitro studies demonstrated that it enhanced JNK phosphorylation through ROS generation. Overall, these findings will assist the discovery of new compounds targeting JNK for use in HER2-positive BC cells.

The intracellular fate and transport mechanism of shape, size and rigidity varied nanocarriers for understanding their oral delivery efficiency

Nanocarriers have become an effective strategy to overcome epithelial absorption barriers. During the absorption process, the endocytosis mechanisms, cell internalization pathways, and transport efficiency of nanocarriers are greatly impacted by their physical properties. To understand the relationship between physical properties of nanocarriers and their abilities overcoming multiple absorption barriers, nanocarriers with variable physical properties were prepared via self-assembly of hydrolyzed α-lactalbumin peptide fragments. The impacts of size, shape, and rigidity of nanocarriers on epithelial cells endocytosis mechanisms, internalization pathways, transport efficiency, and bioavailability were studied systematically. The results showed that nanospheres were mainly internalized via clathrin-mediated endocytosis, which was then locked in lysosomes and degraded enzymatically in cytoplasm. While macropinocytosis was the primary pathway of nanotubes and transported to the endoplasmic reticulum and Golgi apparatus, resulting in a high drug concentration and sustained release in cytoplasm. Besides, nanotubes can overcome the multi-drug resistance by inhibiting the P-glycoprotein efflux. Furthermore, nanotubes can open intercellular tight-junctions instantaneously and reversibly, which promotes transport into blood circulation. The aqueous solubility of hydrophobic bioactive mangiferin (Mgf) was improved by nanocarriers. Most importantly, the bioavailability of Mgf was the highest for cross-linked short nanotube (CSNT) which outperformed free Mgf and other formulations by in vivo pharmacokinetic studies. Finally, Mgf-loaded CSNT showed an excellent therapeutic efficiency in vivo for the intervention of streptozotocin-induced diabetes. These results indicate that cross-linked α-lactalbumin nanotubes could be an effective nanocarrier delivery system for improving the epithelium cellular absorption and bioavailability of hydrophobic bioactive compounds.

Role of c-Jun NH2 -terminal kinase-mediated mitogen-activated protein kinase pathway in response to pesticides in Apis cerana cerana

The mitogen-activated protein kinase (MAPK) cascade pathway plays an important role in regulating stress responses. The function of the c-Jun NH₂ -terminal kinase (JNK), a component of the MAPK cascade pathway, in Apis cerana cerana (Acc) remains unclear. Here, JNK was isolated and identified from Acc. Bioinformatics analyses revealed there is a typical serine/threonine protein kinase catalytic domain in the AccJNK protein. An expression profile analysis showed that AccJNK was significantly induced by pesticide treatments. To further explore the functional mechanisms of AccJNK, a yeast 2-hybrid screen was performed, activator protein-1 (AP-1) was screened as the interaction partner of AccJNK, and the interaction relationship was further verified by pull-down assay. Quantitative real-time polymerase chain reaction showed the expression pattern of AccAP-1 was similar to that of AccJNK. After a knockdown of AccJNK or AccAP-1 by RNA interference, the survival rate of Acc after pesticide treatments increased. Additionally, the expression levels of antioxidant-related genes and the activities of antioxidant enzymes increased, suggesting that the knockdown of AccJNK or AccAP-1 increased the antioxidant capacity of bees. Our study revealed that the JNK-mediated MAPK pathway responds to pesticide stress by altering the antioxidant capacity of Acc.

c-Jun regulates flotillin 2 transcription to benefit viral accumulation in insect vectors

The c-Jun N-terminal kinase (JNK) signaling pathway plays a critical role in viral infection in host cells. In addition to triggering immune reactions against pathogens, the JNK signaling pathway has also been found to benefit viral infection. Our previous work showed that JNK activation facilitated rice stripe virus (RSV) accumulation in the insect vector small brown planthopper, but the underlying mechanisms remain elusive. Here, we revealed a link between JNK activation and the transcriptional upregulation of the plasma membrane protein flotillin 2, which mediates RSV cell entry. c-Jun, a downstream substrate of JNKs, was identified as a transcription factor that targets the promoter of flotillin 2 at three binding sites. Phosphorylated c-Jun, especially at the serine 63 site, promoted the transcriptional activity of c-Jun on flotillin 2. JNK activation or inhibition affected c-Jun phosphorylation status and flotillin 2 expression. In the midguts of planthoppers, RSV infection significantly increased flotillin 2 expression and the phosphorylation level of JNKs and c-Jun. Manipulation of JNK status impacted viral acquisition in midgut cells. These findings reveal a new regulatory mechanism of the JNK signaling pathway and shed light on the virus-supportive effect of this pathway.

Optimizing component formula suppresses lung cancer by blocking DTL-mediated PDCD4 ubiquitination to regulate the MAPK/JNK pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Salvia miltiorrhiza Bunge and Panax ginseng C. A. Meyer have special curative effect on cancer treatment. The optimizing component formula (OCF) extracted from those two herbs was in line with the anti-lung cancer treatment principle of activating blood and supplementing 'Qi'. However, the study on the mechanism of component formula has always been an insurmountable challenge. Nowadays, the application of network pharmacology and artificial intelligence (AI) in the field of TCM provides new ideas for the study of new targets and mechanisms of TCM, which promotes the modernization of TCM.

AIM OF THE STUDY

This study aims to further explore the anti-lung cancer mechanism of OCF by using an integrated strategy of network pharmacology and AI technology.

MATERIALS AND METHODS

Bioinformatic analysis was used to analyze the expression levels, prognosis and survival of DTL and PDCD4 in cancer patients. The binding strength of OCF and DTL was simulated by molecular docking, and the affinity between them was detected by Bio-layer interferometry. Network pharmacology was used to predict the active components, potential targets and pathways of OCF. The association between key targets and their corresponding components and DTL was analyzed by Ingenuity Pathway Analysis (IPA). MTT assay, colony formation assay, wound-healing assay and transwell assay were used to verify the inhibitory effects of OCF on lung cancer cells in vitro. qRT-PCR and Western blot assay were used to detect the effects of OCF on mRNA and protein expression of DTL, PDCD4 and key genes in MAPK/JNK pathways.

RESULTS

Bioinformatics analysis showed that DTL was significantly up-regulated in lung cancer, which was associated with high malignancy rate, high metastasis rate and poor prognosis of primary tumor. PDCD4 was down-regulated in lung cancer, and associated with high metastasis rate and poor prognosis. The good affinity between OCF and DTL was predicted and verified by molecular docking and Bio-layer interferometry. Based on the network pharmacological databases, 40 active components and 220 corresponding targets of OCF were screened out. KEGG analysis showed that OCF component targets were mainly enriched in MAPK signaling pathway. IPA results showed the interrelationship between DTL, PDCD4, MAPK pathway genes and their corresponding OCF components. In addition, in vitro experiments demonstrated anti-lung cancer activity of OCF, as validated, via impairing cell viability and cell proliferation, as well as inhibiting migration and invasion abilities in lung cancer cells. qRT-PCR showed that OCF down-regulated the mRNA expression of DTL, MAP4K1, JNK, c-Jun and c-Myc, and up-regulated the mRNA expression of PDCD4 and P53 genes in A549 lung cancer cells. Western blot suggested that OCF suppressed the protein level of DTL and blocked the ubiquitination of PDCD4 in A549 lung cancer cells, and down-regulated the protein levels of MAP4K1, p-JNK and p-c-Jun while up-regulated the proteins expression level of P53.

CONCLUSIONS

OCF might elicit an anti-lung cancer effect by blocking DTL-mediated PDCD4 ubiquitination and suppression of the MAPK/JNK pathway. Meanwhile, our work revealed that network pharmacology and AI technology strategy are cogent means of studying the active components and mechanism of TCM.

BML-260 promotes the growth of cord blood and mobilized peripheral blood hematopoietic stem and progenitor cells with improved reconstitution ability

Hematopoietic stem cells (HSCs), which are multipotent and have the ability to self-renew, are frequently used in the treatment of hematological diseases and cancer. Small molecules that target HSC quiescence regulators could be used for ex vivo expansion of both mobilized peripheral blood (mPB) and umbilical cord blood (UCB) hematopoietic stem and progenitor cells (HSPC). We identified and investigated 35 small molecules that target HSC quiescence factors. We looked at how they affected HSC activity, such as expansion, quiescence, multilineage capacity, cycling ability, metabolism, cytotoxicity, and genotoxicity. A transplantation study was carried out on immunocompromised mice to assess the expanded cells' repopulation and engraftment abilities. 4-[(5Z)-5-benzylidene-4-oxo-2-sulfanylidene-1,3-thiazolidin-3-yl]benzoic acid (BML)-260 and tosyl-l-arginine methyl ester (TAME) significantly increased both mPB and UCB-HSPC content and activated HSC re-entry into the cell cycle. The improved multilineage capacity was confirmed by the colony forming unit (CFU) assay. Furthermore, gene expression analysis revealed that BML-260 and TAME molecules aided HSC expansion by modulating cell cycle kinetics, such as p27, SKP2, and CDH1. In addition to these in vitro findings, we discovered that BML-260-expanded HSCs had a high hematopoietic reconstitution capacity with increased immune cell content after xenotransplantation into immunocompromised mice. In addition to the BML-260 molecule, a comparison study of serum-containing and serum-free chemically defined media, including various supplements, was performed. These in vitro and xenotransplantation results show that BML-260 molecules can be used for human HSC expansion and regulation of function. Furthermore, the medium composition discovered may be a novel platform for human HSPC expansion that could be used in clinical trials.

The use of integrated text mining and protein-protein interaction approach to evaluate the effects of combined chemotherapeutic and chemopreventive agents in cancer therapy

Combining chemotherapeutic (CT) and chemopreventive (CP) agents for cancer treatment is controversial, and the issue has not yet been conclusively resolved. In this study, by integrating text mining and protein-protein interaction (PPI), the combined effects of these two kinds of agents in cancer treatment were investigated. First, text mining was performed by the Pathway Studio database to study the effects of various agents (CP and CT) on cancer-related processes. Then, each group’s most important hub genes were obtained by calculating different centralities. Finally, the results of in silico analysis were validated by examining the combined effects of hesperetin (Hst) and vincristine (VCR) on MCF-7 cells. In general, the results of the in silico analysis revealed that the combination of these two kinds of agents could be useful for treating cancer. However, the PPI analysis revealed that there were a few important proteins that could be targeted for intelligent therapy while giving treatment with these agents. In vitro experiments confirmed the results of the in silico analysis. Also, Hst and VCR had good harmony in modulating the hub genes obtained from the in silico analysis and inducing apoptosis in the MCF-7 cell line.

Ayurvedic formulations Guduchi and Madhuyashti triggers JNK signaling mediated immune response and adversely affects Huntington phenotype

BACKGROUND

Huntington's disease manifests due to abnormal CAG trinucleotide expansion, in the first exon of the Huntingtin gene and disease progression involves genetic, immune, and environmental components. The pathogenesis is characterized by the formation of Inclusion Bodies, disruption of neuronal circuitry, cellular machinery, and apoptosis, resulting in gradual and progressive loss of neuronal cells, ultimately leading to nervous system dysfunction. Thus, the present study was conducted to assess the effect of two Ayurvedic formulations, Guduchi and Madhuyashti, on Huntington's phenotype, using Drosophila as a model system.

METHOD

The Huntington phenotype was ectopically induced in the Drosophila eye using the UAS-GAL4 binary system and the effect of the two Ayurvedic formulations were assessed by feeding the progenies on them. Degeneration was observed microscopically and Real Time-PCR was done to assay the alterations in the different transcripts of the innate immune pathways and JNK signaling pathway. Immunostaining was performed to assay different gene expression patterns.

RESULT

The present study shows that Guduchi and Madhuyashti, endowed with immunomodulatory and intellect promoting properties, aggravates polyQ mediated neurodegeneration. We provide evidence that these formulations enhance JNK signaling by activating the MAP 3 K, dTAK1, which regulates the expression of Drosophila homologue for JNK. Sustained, rather than a transient expression of JNK leads to excessive production of Anti-Microbial Peptides without involving the canonical transcription factors of the Toll or IMD pathways, NF-κB. Enhanced JNK expression also increases caspase levels, with a concomitant reduction in cell proliferation, which may further contribute to increased degeneration.

CONCLUSION

This is a report linking the functional relevance of Guduchi and Madhuyashti with molecular pathways, which can be important for understanding their use in therapeutic applications and holds promise for mechanistic insight into the mammalian counterpart.

Mechanism of effects of nickel or nickel compounds on intestinal mucosal barrier

As an important metal in industry, national defense, and production, nickel widely exists in nature and is also a necessary trace element for human beings and animals. Nickel deficiency will affect the growth and development of animals, the contents of related active substances, enzymes and other essential elements in vivo. However, excessive nickel or longer nickel exposure can induce excessive free radicals (reactive oxygen species and reactive nitrogen) in the body, which can lead to a variety of cell damage, apoptosis and canceration, and ultimately pose negative effects on the health of the body. Among them, the intestinal tract, as the largest interface between the body and the external environment, greatly increases the contact probability between nickel or nickel compounds and the intestinal mucosal barrier, thus, the intestinal structure and function are also more vulnerable to nickel damage, leading to a series of related diseases such as enteritis. Therefore, this paper briefly analyzed the damage mechanism of nickel or its compounds to the intestinal tract from the perspective of four intestinal mucosal barriers: mechanical barrier, immune barrier, microbial barrier and chemical barrier, we hope to make a certain theoretical contribution to the further research and the prevention and treatment of nickel related diseases.

The Role of PKC-MAPK Signalling Pathways in the Development of Hyperglycemia-Induced Cardiovascular Complications

Cardiovascular disease is the most common cause of death among diabetic patients worldwide. Hence, cardiovascular wellbeing in diabetic patients requires utmost importance in disease management. Recent studies have demonstrated that protein kinase C activation plays a vital role in the development of cardiovascular complications via its activation of mitogen-activated protein kinase (MAPK) cascades, also known as PKC-MAPK pathways. In fact, persistent hyperglycaemia in diabetic conditions contribute to preserved PKC activation mediated by excessive production of diacylglycerol (DAG) and oxidative stress. PKC-MAPK pathways are involved in several cellular responses, including enhancing oxidative stress and activating signalling pathways that lead to uncontrolled cardiac and vascular remodelling and their subsequent dysfunction. In this review, we discuss the recent discovery on the role of PKC-MAPK pathways, the mechanisms involved in the development and progression of diabetic cardiovascular complications, and their potential as therapeutic targets for cardiovascular management in diabetic patients.

Neuroinflammatory Triangle Presenting Novel Pharmacological Targets for Ischemic Brain Injury

Ischemic stroke is one of the leading causes of morbidity and mortality globally. Hundreds of clinical trials have proven ineffective in bringing forth a definitive and effective treatment for ischemic stroke, except a myopic class of thrombolytic drugs. That, too, has little to do with treating long-term post-stroke disabilities. These studies proposed diverse options to treat stroke, ranging from neurotropic interpolation to venting antioxidant activity, from blocking specific receptors to obstructing functional capacity of ion channels, and more recently the utilization of neuroprotective substances. However, state of the art knowledge suggests that more pragmatic focus in finding effective therapeutic remedy for stroke might be targeting intricate intracellular signaling pathways of the 'neuroinflammatory triangle': ROS burst, inflammatory cytokines, and BBB disruption. Experimental evidence reviewed here supports the notion that allowing neuroprotective mechanisms to advance, while limiting neuroinflammatory cascades, will help confine post-stroke damage and disabilities.

Involvement of c-Jun N-terminal kinase 2 (JNK2) in Endothelin-1 (ET-1) Mediated Neurodegeneration of Retinal Ganglion Cells

Purpose

The goal of this study was to determine whether JNK2 played a causative role in endothelin-mediated loss of RGCs in mice.

Methods

JNK2^−/− and wild type (C57BL/6) mice were intravitreally injected in one eye with 1 nmole of ET-1, whereas the contralateral eye was injected with the vehicle. At two time points (two hours and 24 hours) after the intravitreal injections, mice were euthanized, and phosphorylated c-Jun was assessed in retinal sections. In a separate set of experiments, JNK2^−/− and wild type mice were intravitreally injected with either 1 nmole of ET-1 or its vehicle and euthanized seven days after injection. Retinal flat mounts were stained with antibodies to the RGC marker, Brn3a, and surviving RGCs were quantified. Axonal degeneration was assessed in paraphenylenediamine stained optic nerve sections.

Results

Intravitreal ET-1 administration produced a significant increase in immunostaining for phospho c-Jun in wild type mice, which was appreciably lower in the JNK2 ^−/− mice. A significant (P < 0.05) 26% loss of RGCs was found in wild type mice, seven days after injection with ET-1. JNK2^−/− mice showed a significant protection from RGC loss following ET-1 administration, compared to wild type mice injected with ET-1. A significant decrease in axonal counts and an increase in the collapsed axons was found in ET-1 injected wild type mice eyes.

Conclusions

JNK2 appears to play a major role in ET-1 mediated loss of RGCs in mice. Neuroprotective effects in JNK2^−/− mice following ET-1 administration occur mainly in the soma and not in the axons of RGCs.

Protective Effect of Dexmedetomidine on Acute Lung Injury via the Upregulation of Tumour Necrosis Factor-α-Induced Protein-8-like 2 in Septic Mice

The aim of the present study was to investigate whether TIPE2 participates in the protective actions of dexmedetomidine (DEX) in a mouse model of sepsis-induced acute lung injury (ALI). We administered TIPE2 adeno-associated virus (AAV-TIPE2) intratracheally into the lungs of mice. Control mice were infected with an adeno-associated virus expressing no transgene. Three weeks later, an animal model of caecal ligation-perforation (CLP)-induced sepsis was established. DEX was administered intravenously 30 min after CLP. Twenty-four hours after sepsis, lung injury was assayed by lung histology, the ratio of polymorphonuclear leukocytes (PMNs) to total cells in the bronchoalveolar lavage fluid (BALF), myeloperoxidase (MPO) activity, BALF protein content and the lung wet-to-dry (W/D) weight ratio. Proinflammatory factor levels in the BALF of mice were measured. The protein expression levels in lung tissues were analysed by Western blotting. The results showed that DEX treatment markedly mitigated sepsis-induced lung injury, which was characterized by the deterioration of histopathology, histologic scores, the W/D weight ratio and total protein levels in the BALF. Moreover, DEX markedly attenuated sepsis-induced lung inflammation, as evidenced by the decrease in the number of PMNs in the BALF, lung MPO activity and proinflammatory cytokines in the BALF. In addition, DEX dramatically prevented sepsis-induced pulmonary cell apoptosis in mice, as reflected by decreases in the number of TUNEL-positive cells, the protein expression of cleaved caspase-9 and cleaved caspase 3 and the Bax/Bcl-2 ratio. In addition, evaluation of protein expression showed that DEX blocked sepsis-activated JNK phosphorylation and NF-κB p65 nuclear translocation. Similar results were also observed in the TIPE2 overexpression group. Our study demonstrated that DEX inhibits acute inflammation and apoptosis in a murine model of sepsis-stimulated ALI via the upregulation of TIPE2 and the suppression of the activation of the NF-κB and JNK signalling pathways.

The Inhibition Effect of the Seaweed Polyphenol, 7-Phloro-Eckol from Ecklonia Cava on Alcohol-Induced Oxidative Stress in HepG2/CYP2E1 Cells

The liver is vulnerable to oxidative stress-induced damage, which leads to many diseases, including alcoholic liver disease (ALD). Liver disease endanger people's health, and the incidence of ALD is increasing; therefore, prevention is very important. 7-phloro-eckol (7PE) is a seaweed polyphenol, which was isolated from Ecklonia cava in a previous study. In this study, the antioxidative stress effect of 7PE on HepG2/CYP2E1 cells was evaluated by alcohol-induced cytotoxicity, DNA damage, and expression of related inflammation and apoptosis proteins. The results showed that 7PE caused alcohol-induced cytotoxicity to abate, reduced the amount of reactive oxygen species (ROS) and nitric oxide (NO), and effectively inhibited DNA damage in HepG2/CYP2E1 cells. Additionally, the expression levels of glutathione (GSH), superoxide dismutase (SOD), B cell lymphoma 2 (Bcl-2), and Akt increased, while γ-glutamyltransferase (GGT), Bcl-2 related x (Bax), cleaved caspase-3, cleaved caspase-9, nuclear factor-κB (NF-κB), and JNK decreased. Finally, molecular docking proved that 7PE could bind to BCL-2 and GSH protein. These results indicate that 7PE can alleviate the alcohol-induced oxidative stress injury of HepG2 cells and that 7PE may have a potential application prospect in the future development of antioxidants.

Emodin Induced Necroptosis and Inhibited Glycolysis in the Renal Cancer Cells by Enhancing ROS

Renal cell carcinoma (RCC) is a tumor with unpredictable presentation and poor clinical outcome. RCC is always resistant to chemotherapy and radiation, and weakly sensitive to immunotherapeutic agents. Therefore, novel agents and approaches are urgently needed for the treatment of RCC. Emodin, an anthraquinone compound extracted from rhubarb and other traditional Chinese herbs, has been implicated in a wide variety of pharmacological effects, such as anti-inflammatory, antiviral, and antitumor activities. However, its role in RCC remains unknown. In this study, we found that emodin effectively killed renal cancer cells without significant toxicity to noncancerous cell HK-2. Flow cytometry assay with Annexin V-FITC and PI demonstrated that emodin induces necroptosis, but not apoptosis, in renal cancer cells. Meanwhile, the phosphorylation levels of RIP1 and MLKL, the key necroptosis-related proteins, were significantly increased. To explore how emodin inhibits kidney tumor growth, we tested reactive oxygen species (ROS) levels and found that the levels of ROS increased upon emodin treatment in a dose-dependent manner. Further studies demonstrated that emodin induces necroptosis through ROS-mediated activation of JNK signaling pathway and also inhibits glycolysis by downregulation of GLUT1 through ROS-mediated inactivation of the PI3K/AKT signaling pathway. Our findings revealed the potential mechanisms by which emodin suppresses renal cancer cell growth and will help develop novel therapeutic approaches for patients with JNK- or PI3K/AKT-dysregulated renal cancer.

Mangiferin prevents the impairment of mitochondrial dynamics and an increase in oxidative stress caused by excessive fluoride in SH-SY5Y cells

Previous studies both invivo and in vitro have revealed that high levels of fluoride cause neurotoxicity. Mangiferin has been reported to possess antioxidant, antiapoptotic, and anti-inflammatory properties. The present study was designed to characterize the mechanisms by which mangiferin protects against NaF-induced neurotoxicity. Increased levels of proapoptotic Bax, Caspase-3, Caspase-9, and cleaved-caspase 3, as well as a decreased level of antiapoptotic Bcl-2 induced by fluoride in human neuroblastoma SH-SY5Y cells, these effects were prevented by pretreatment of mangiferin. In addition, mangiferin attenuated the enhancement of p-JNK, reductions of Nrf2 and HO-1, and increased level of the mitochondrial fission proteins Drp1 caused by fluoride. Moreover, oxidative stress, as reflected in the levels of reactive oxygen species, 8-hydroxy-2'-deoxyguanosine, and 4-hydroxynonenal, was elevated by fluoride and these effects were again ameliorated by mangiferin. In conclusion, protection by mangiferin against fluoride-induced neurotoxicity involves normalizing the impaired mitochondrial apoptotic pathway and dynamics and reducing oxidative stress via inactivation of the JNK and activation of the Nrf2/HO-1 pathways.

RAGE signaling is required for AMPA receptor dysfunction in the hippocampus of hyperglycemic mice

Diabetes in humans has been associated for a long time with cognitive dysfunction. In rodent animal models, cognitive dysfunction can manifest as impaired hippocampal synaptic plasticity. Particular attention has been concentrated on the receptor for advanced glycation end products (RAGE), which is implicated in multiple diabetic complications involving the development of vascular and peripheral nerve abnormalities. In this study, we hypothesize that RAGE signaling alters glutamate receptor function and expression, impairing synaptic transmission in the hippocampus. Using preparations of hippocampal slices from male mice, we show a RAGE-dependent decrease in long-term potentiation (LTP) and an increase in paired-pulse facilitation (PPF) following streptozotocin (STZ)-induced diabetes. Consistently, in hippocampal cultures from male and female neonatal mice, high glucose caused a RAGE-dependent reduction of AMPA- but not NMDA-evoked currents, and an increase in cytosolic reactive oxygen species (ROS). Consistently, when cultures were co-treated with high glucose and the RAGE antagonist FPS-ZM1, AMPA-evoked currents were unchanged. Hippocampi from STZ-induced hyperglycemic wild type (WT) mice showed increased RAGE expression concomitant with a decrease of both expression and phosphorylation (Ser 831 and 845) of the AMPA GluA1 subunit. We found these changes correlated to activation of the MAPK pathway, consistent with decreased pJNK/JNK ratio and the JNK kinase, pMEK7. As no changes in expression or phosphorylation of regulatory proteins were observed in hippocampi from STZ-induced hyperglycemic RAGE-KO mice, we report a RAGE-dependent impairment in the hippocampi of hyperglycemic WT mice, with reduced AMPA receptor expression/function and LTP deficits.

Low-dose suspended graphene oxide nanosheets induce antioxidant response and osteogenic differentiation of bone marrow-derived mesenchymal stem cells via JNK-dependent FoxO1 activation

Large bone defects caused by bone-related diseases and traumatic injuries can disrupt the self-healing potential of bone tissue. Mesenchymal stem cells (MSCs) are known as promising cell sources for bone tissue regeneration. Graphene oxide (GO), a derivative of graphene, has been recently used for controlling the differentiation of stem cells towards bone-forming cells. However, the effect of GO on the intracellular redox system in MSCs is still unknown. In this study, we found that low-dose GO nanosheets (0.1 μg mL-1) did not affect the viability and slightly increased the proliferation of BM-MSCs. Moreover, they could also maintain the redox balance by upregulating the antioxidant genes such as MnSOD and catalase during osteogenic differentiation. The osteoinductive and antioxidative effects of the low-dose GO nanosheets were regulated by the activation and nuclear localization of FoxO1, and its activation was dependent on the JNK activity. The blockade of JNK activity by SP600125 inhibited the nuclear translocation of FoxO1, and subsequently suppressed the osteogenic differentiation and antioxidant defense system of BM-MSCs. Overall, our results show that the osteoinductive and antioxidative effects of low-dose GO nanosheets occur through the activation of the JNK and FoxO1 signaling pathways.

Dehydration stress alters the mitogen-activated-protein kinase signaling and chaperone stress response in Xenopus laevis

In arid conditions, the African Clawed frog Xenopus laevis enters a state of estivation dormancy as an adaptive survival strategy. Under estivation, X. laevis experience severe dehydration stress as 25-35% of total body water is lost. Dehydration in X. laevis can lead to periods of hypoxia due to elevated blood viscosity that impedes tissue perfusion. To understand how X. laevis survives under such stress, we studied the regulation pattern of key mitogen-activated protein kinases (MAPK) and their downstream transcription factors, along with several heat shock proteins in the oxygen sensitive brain and heart tissue of X. laevis under dehydration stress. Our study revealed that the activation phosphorylation residues of MAPK including JNK and MSK and their downstream transcription factors c-Jun and ATF2 are significantly decreased in the heart under dehydration. Given that JNK, c-Jun, and ATF2 are known positive regulators of apoptosis, this regulatory pattern suggest that a state of pro-survival signals may be established in the dehydrated heart. In support of this, protein levels of HSP60, a pro-apoptotic mitochondrial chaperone, was also downregulated in the heart in response to dehydration stress. In the brain tissue, most proteins remain unchanged with the exception of the apoptosis regulating p53 transcription factor, which showed a significant decrease in its activating phosphorylation residue under dehydration. Overall, our study revealed that in the Xenopus brain and heart, a specific suppression pattern of MAPK, transcription factors, and HSP takes place to potentially establish a state of pro-survival under dehydration stress.

JNK signaling pathway regulates the development of ovaries and synthesis of vitellogenin (Vg) in the swimming crab Portunus trituberculatus

The development of Portunus trituberculatus egg cells is directly related to the nutritional status of the fertilized egg, which affects the key production stages of offspring hatching. Vitellogenin plays a key role in the nutrient supply required for the development of the egg cells. The c-Jun N-terminal kinase (JNK) is an important member of the mitogen-activated protein kinase (MAPK) superfamily and plays an important role in cell proliferation, transformation, differentiation, and apoptosis. At present, there are no reports on the involvement of the JNK signaling pathway in the reproductive regulation of P. trituberculatus. In this study, rapid amplification of complementary DNA ends amplification technology was used to clone the full length of JNK complementary DNA, which has a length of 2094 bp, including an open reading frame (ORF) of 1266 bp encoding a 421-amino acid protein. The protein includes the S_TKC conserved domain with a TPY phosphorylation site, which is a typical feature of the JNK gene family. Observing tissue sections found the oocytes in the inhibitor group developed slowly, while the oocytes in the activated group showed accelerated development. Meanwhile, Portunus trituberculatus JNK and vitellogenin (Vg) genes exhibited the same trend in the hepatopancreas and ovaries, and the expression of the SP600125 group was downregulated (P < 0.05), while the anisomycin group was upregulated (P < 0.05). In addition, JNK enzyme activity and vitellin (Vn) content in the ovarian tissue showed that the JNK activity of the SP600125 group decreased, while activity increased in the anisomycin group. The accumulation of Vn content in the SP600125 group decreased, and that in the anisomycin group increased. In summary, after injection with inhibitor or activator, the JNK signaling pathway of P. trituberculatus was inhibited or activated, the accumulation of Vn in the ovary was reduced or increased, and ovarian development was inhibited or accelerated, respectively. These results indicated that the JNK signaling pathway is involved in the regulation of Vg synthesis and ovarian development in P. trituberculatus. The results of this study further add to the knowledge of the breeding biology of P. trituberculatus and provide a theoretical reference for the optimization of breeding techniques in aquaculture production systems.

Tissue-Specific Metabolic Regulation of FOXO-Binding Protein: FOXO Does Not Act Alone

The transcription factor forkhead box (FOXO) controls important biological responses, including proliferation, apoptosis, differentiation, metabolism, and oxidative stress resistance. The transcriptional activity of FOXO is tightly regulated in a variety of cellular processes. FOXO can convert the external stimuli of insulin, growth factors, nutrients, cytokines, and oxidative stress into cell-specific biological responses by regulating the transcriptional activity of target genes. However, how a single transcription factor regulates a large set of target genes in various tissues in response to a variety of external stimuli remains to be clarified. Evidence indicates that FOXO-binding proteins synergistically function to achieve tightly controlled processes. Here, we review the elaborate mechanism of FOXO-binding proteins, focusing on adipogenesis, glucose homeostasis, and other metabolic regulations in order to deepen our understanding and to identify a novel therapeutic target for the prevention and treatment of metabolic disorders.

Selective inhibitors for JNK signalling: a potential targeted therapy in cancer

c-Jun N-terminal kinase (JNK) signalling regulates both cancer cell apoptosis and survival. Emerging evidence show that JNK promoted tumour progression is involved in various cancers, that include human pancreatic-, lung-, and breast cancer. The pro-survival JNK oncoprotein functions in a cell context- and cell type-specific manner to affect signal pathways that modulate tumour initiation, proliferation, and migration. JNK is therefore considered a potential oncogenic target for cancer therapy. Currently, designing effective and specific JNK inhibitors is an active area in the cancer treatment. Some ATP-competitive inhibitors of JNK, such as SP600125 and AS601245, are widely used in vitro; however, this type of inhibitor lacks specificity as they indiscriminately inhibit phosphorylation of all JNK substrates. Moreover, JNK has at least three isoforms with different functions in cancer development and identifying specific selective inhibitors is crucial for the development of targeted therapy in cancer. Some selective inhibitors of JNK are identified; however, their clinical studies in cancer are relatively less conducted. In this review, we first summarised the function of JNK signalling in cancer progression; there is a focus on the discussion of the novel selective JNK inhibitors as potential targeting therapy in cancer. Finally, we have offered a future perspective of the selective JNK inhibitors in the context of cancer therapies. We hope this review will help to further understand the role of JNK in cancer progression and provide insight into the design of novel selective JNK inhibitors in cancer treatment.

JNK Signaling Pathway Mediates Acetaminophen-Induced Hepatotoxicity Accompanied by Changes of Glutathione S-Transferase A1 Content and Expression

Acetaminophen (APAP) is an analgesic-antipyretic drug and widely used in clinics. Its overdose may cause serious liver damage. Here, we examined the mechanistic role of c-Jun N-terminal kinase (JNK) signaling pathway in liver injury induced by different doses of APAP. Male mice were treated with APAP (150 and 175 mg·kg^-1), and meanwhile JNK inhibitor SP600125 was used to interfere APAP-induced liver damage. The results showed that JNK signaling pathway was activated by APAP in a dose-dependent manner. C-Jun N-terminal kinase inhibitor decreased JNK and c-Jun activation significantly (P < 0.01) at 175 mg·kg^-1 APAP dose, and phosphorylation levels of upstream proteins of JNK were also decreased markedly (P < 0.05). In addition, serum aminotransferases activities and hepatic oxidative stress increased in a dose-dependent manner with APAP treatment, but the levels of aminotransferases and oxidative stress decreased in mice treated with JNK inhibitor, which implied that JNK inhibition ameliorated APAP-induced liver damage. It was observed that apoptosis was increased in APAP-induced liver injury, and SP600125 can attenuate apoptosis through the inhibition of JNK phosphorylation. Meanwhile, glutathione S-transferases A1 (GSTA1) content in serum was enhanced, while GSTA1 content and expression in liver reduced significantly with administration of APAP (150 and 175 mg·kg^-1). After inhibiting JNK, GSTA1 content in serum decreased significantly (P < 0.01); meanwhile, GSTA1 content and expression in liver enhanced. These findings suggested that JNK signaling pathway mediated APAP-induced hepatic injury, which was accompanied by varying GSTA1 content and expression in liver and serum.

DEPDC1 promotes cell proliferation and suppresses sensitivity to chemotherapy in human hepatocellular carcinoma

Background: Hepatocellular carcinoma (HCC) is one of the major causes of tumor-related morbidity and mortality worldwide. Accumulating evidence has revealed that aberrant expression of crucial cancer-related genes contributes to hepatocellular carcinogenesis. This study aimed to characterize the biological role of DEP domain containing 1 (DEPDC1), a novel cancer-related gene, in HCC and illuminate the potential molecular mechanisms involved.

Materials and methods: Quantitative real-time PCR (qRT-PCR), Western blotting and immunohistochemical (IHC) staining were used to characterize the expression patterns of DEPDC1 in tumorous tissues and adjacent normal tissues. Kaplan–Meier survival analysis was launched to evaluate the relationship between DEPDC1 expression and overall survival. CCK8 assay, colony formation and flow cytometry were performed to investigate the effects of DEPDC1 on HCC cell viability, clonogenic capability and cell apoptosis. Murine xenograft models were established to determine the effect of DEPDC1 on tumor growth in vivo. SP600125, a JNK specific inhibitor, was applied to carriy out mechanistic studies.

Results: DEPDC1 was significantly up-regulated in HCC tissues compared with para-cancerous tissues. Besides, patients with high DEPDC1 expression experienced a significantly shorter overall survival. Functional investigations demonstrated that DEPDC1 overexpression facilitated HCC cell proliferation and suppressed cell apoptosis, whereas DEPDC1 depletion inhibited cell proliferation and promoted cell apoptosis. Furthermore, DEPDC1 ablation suppressed tumorigenecity of HCC cells in murine xenograft models. Mechanistic studies uncovered that JNK signaling pathway mediated the promoting effects of DEPDC1 on HCC cell viability and chemotherapy resistance.

Conclusion: Collectively, our data may provide some evidence for DEPDC1 as a candidate therapeutic target for HCC.

Metabolic disorder induces fatty liver in Japanese seabass, Lateolabrax japonicas fed a full plant protein diet and regulated by cAMP-JNK/NF-kB-caspase signal pathway

A 10-week growth trial was conducted to investigate the effects of replacing dietary fishmeal with plant proteins on nutrition metabolism, immunity, inflammation and apoptosis responses in liver tissues of Japanese seabass, Lateolabrax japonicas (initial body weight = 10.42 ± 0.01 g). Two isonitrogenous and isoenergetic diets were formulated. A basal diet containing 54% fishmeal (FM), whereas another diet was prepared by totally replacing FM with a plant protein blend (PP) composed with soybean protein concentrate and cottonseed protein concentrate. Although essential amino acids, fatty acids, and available phosphorus had been balanced according to the FM diet profile, the significantly lower growth performance, metabolic disorder, and fatty liver symptom were observed in the PP group. Compared with the FM group, fish in the PP group showed significantly lower plasma free EAA level and PPV. Glucose metabolism disorder was expressed as the uncontrollable fasting glycolysis and pyruvate aerobic oxidation at postprandial 24 h with significantly up-regulated GK, PK and PDH genes expression, which potentially over-produced acetyl-CoA as the substrate for protein and lipid synthesis. Significantly reduced plasma GLU, but increased GC level, along with very significantly reduced liver GLY storage could be observed in the PP group. Plasma TG and hepatic NEFA contents were significantly decreased, but the hepatic TC content was very significantly increased in the PP group, in addition, hepatocyte vacuolation appeared. The significantly up-regulated cholesterol synthesis gene (HMGCR) expression but down-regulated bile acid synthesis gene (CYP7A1) expression could be the main reason for the fatty liver induced by cholesterol accumulation. The reduced plasma IgM content accompanied by the up-regulated mRNA levels of pro-inflammatory cytokines (TNFα and IL1β) and activated apoptosis signals of liver tissues were found in the PP group. The hyperthyroidism (higher plasma T3 and T4) and the accelerated energy metabolism rate decreased the growth performance in the PP group. The activated p65NF-kB may promote the hepatocytes apoptosis via the extrinsic pathway (caspase8/caspase3). Simultaneously, a "self-saving" response could be observed that activated cAMP promoted the lipolysis/β-oxidation process and up-regulated gene expression of anti-inflammatory cytokine IL10 via promoting CREB expression, further inhibited the over-phosphorylation of JNK protein, which might impede the intrinsic apoptosis pathway (caspase9/caspase3). In conclusion, the nutrient and energy metabolic disorder induced fatty liver related to the cholesterol accumulation in Japanese seabass fed full PP diet, which was under the regulation by cAMP-JNK/NF-kB-caspase signaling pathway. The hemostasis phosphorylation of JNK protein protected the liver tissues from more serious damage.

Stress signaling in breast cancer cells induces matrix components that promote chemoresistant metastasis

Metastatic progression remains a major burden for cancer patients and is associated with eventual resistance to prevailing therapies such as chemotherapy. Here, we reveal how chemotherapy induces an extracellular matrix (ECM), wound healing, and stem cell network in cancer cells via the c-Jun N-terminal kinase (JNK) pathway, leading to reduced therapeutic efficacy. We find that elevated JNK activity in cancer cells is linked to poor clinical outcome in breast cancer patients and is critical for tumor initiation and metastasis in xenograft mouse models of breast cancer. We show that JNK signaling enhances expression of the ECM and stem cell niche components osteopontin, also called secreted phosphoprotein 1 (SPP1), and tenascin C (TNC), that promote lung metastasis. We demonstrate that both SPP1 and TNC are direct targets of the c-Jun transcription factor. Exposure to multiple chemotherapies further exploits this JNK-mediated axis to confer treatment resistance. Importantly, JNK inhibition or disruption of SPP1 or TNC expression sensitizes experimental mammary tumors and metastases to chemotherapy, thus providing insights to consider for future treatment strategies against metastatic breast cancer.

Role of D-GADD45 in JNK-Dependent Apoptosis and Regeneration in Drosophila

The GADD45 proteins are induced in response to stress and have been implicated in the regulation of several cellular functions, including DNA repair, cell cycle control, senescence, and apoptosis. In this study, we investigate the role of D-GADD45 during Drosophila development and regeneration of the wing imaginal discs. We find that higher expression of D-GADD45 results in JNK-dependent apoptosis, while its temporary expression does not have harmful effects. Moreover, D-GADD45 is required for proper regeneration of wing imaginal discs. Our findings demonstrate that a tight regulation of D-GADD45 levels is required for its correct function both, in development and during the stress response after cell death.

JNK signaling in cancer cell survival

c-Jun N-terminal kinase (JNK) is involved in cancer cell apoptosis; however, emerging evidence indicates that this Janus signaling promotes cancer cell survival. JNK acts synergistically with NF-κB, JAK/STAT, and other signaling molecules to exert a survival function. JNK positively regulates autophagy to counteract apoptosis, and its effect on autophagy is related to the development of chemotherapeutic resistance. The prosurvival effect of JNK may involve an immune evasion mechanism mediated by transforming growth factor-β, toll-like receptors, interferon-γ, and autophagy, as well as compensatory JNK-dependent cell proliferation. The present review focuses on recent advances in understanding the prosurvival function of JNK and its role in tumor development and chemoresistance, including a comprehensive analysis of the molecular mechanisms underlying JNK-mediated cancer cell survival. There is a focus on the specific "Yin and Yang" functions of JNK1 and JNK2 in the regulation of cancer cell survival. We highlight recent advances in our knowledge of the roles of JNK in cancer cell survival, which may provide insight into the distinct functions of JNK in cancer and its potential for cancer therapy.

Targeting c-MET by Tivantinib through synergistic activation of JNK/c-jun pathway in cholangiocarcinoma

Clinical treatment options for human cholangiocarcinoma (CC) are limited. c-MET, a high-affinity receptor for hepatocyte growth factor (HGF), is deregulated in many cancers. Its role in cholangiocarcinogenesis remains unclear. In current study, 23 corresponding tumor- and non-tumor tissues, taken from patients with intrahepatic (iCC) and perihilar cholangiocarcinoma (pCC), who underwent liver resection, were analyzed. The relationship of clinicopathological features and c-MET, as well as c-jun N-terminal kinase (JNK) was evaluated. The anti-tumor effects of Tivantinib, a small-molecule inhibitor with potent activity against the c-MET kinase, was investigated in three human CC cell lines, namely HUCC-T1, TFK-1, and EGI-1. In comparison with the results obtained in non-tumor tissue samples, c-MET was overexpressed in 91.3 % of tumor tissues (p < 0.01). The JNK expression was higher in tumor tissue compared with the corresponding non-tumor tissue sample in 17.4% patients (p < 0.01). The inhibition of aberrant c-MET expression in human CC cell lines was achieved by blocking the phosphorylation of c-MET with Tivantinib. Notable losses in cell viability and colony-forming capability were detected (p < 0.01). Synergistic activation of the JNK/c-jun pathway was demonstrated after Tivantinib treatment. Knockdown of the JNK by siRNA or competitive binding of c-MET receptor by stimulation with HGF-antagonized anti-tumor effects of Tivantinib was observed. Our data suggest that inhibition of c-MET could be a possible alternative approach for the treatment of human CC, for which Tivantinib may an effective inhibitor. The synergistic activation of the JNK/c-jun pathway contributed to the elevated apoptosis in CC cells via treatment with Tivantinib.

Poncirus Trifoliata (L.) Raf. Extract Inhibits the Development of Atopic Dermatitis-like Lesions in Human Keratinocytes and NC/Nga mice

This study investigated the anti-allergic effect of Poncirus trifoliata (L.) Raf. (PT) on human keratinocytic HaCaT cells in vitro and on 2,4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis-like lesions in vivo. The release of TARC, MCP-1, IL-6 and IL-8 is increased by IFN-γ and TNF-α in HaCaT cells, and PT extract suppressed the increased production of TARC, MCP-1, IL-6, and IL-8. PT extract recovered the expression of filaggrin decreased by IFN-γ and TNF-α. in vivo experiment, PT administration decreased the skin severity score, thickening of the epidermis, movement of inflammatory cells into the dermis, and serum IgE level as compared to DNCB treatment. Moreover, the decrease of filaggrin and loricrin induced by DNCB treatment was recovered by PT administration. The levels of IL-4, IL-5, IL-13 and eotaxin in mouse splenocytes increased after treatment with concanavalin A, and the secretions of IL-4, IL-5, IL-13 and eotaxin were lower in the PT-treated group than in the DNCB group. These findings may indicate that PT is useful in drug development for the treatment of AD.

Obesity-Induced TNFα and IL-6 Signaling: The Missing Link between Obesity and Inflammation-Driven Liver and Colorectal Cancers

Obesity promotes the development of numerous cancers, such as liver and colorectal cancers, which is at least partly due to obesity-induced, chronic, low-grade inflammation. In particular, the recruitment and activation of immune cell subsets in the white adipose tissue systemically increase proinflammatory cytokines, such as tumor necrosis factor α (TNFα) and interleukin-6 (IL-6). These proinflammatory cytokines not only impair insulin action in metabolic tissues, but also favor cancer development. Here, we review the current state of knowledge on how obesity affects inflammatory TNFα and IL-6 signaling in hepatocellular carcinoma and colorectal cancers.

Pilose antler polypeptide protects against sevoflurane‑mediated neurocyte injury

Pilose antler polypeptide (PAP) is an active substance isolated from the traditional Chinese medicine pilose antler, which possesses multiple biological activities. In the present study, the role and mechanism of PAP in sevoflurane (SEV)-induced neurocyte injury was explored. Cell viability was determined by Cell Counting kit-8 assay. Cell proliferation and apoptosis were analyzed by flow cytometry. Western blotting and reverse transcription-quantitative polymerase chain reaction analysis were used to evaluate the protein and mRNA expression levels, respectively. The results revealed that PAP enhanced the cell viability of SEV-treated nerve cells. In addition, through modulation of apoptosis-associated protein expression, PAP suppressed SEV-induced nerve cell apoptosis. Furthermore, PAP activated the p38 mitogen-activated protein kinase (p38)/c-Jun N-terminal kinase (JNK) pathway in the neurocyte injury model, whereas inhibition of the p38/JNK pathway reversed the beneficial effects produced by PAP. In conclusion, PAP protected against SEV-mediated neurocyte injury via upregulation of the p38/JNK pathway. The present findings suggested that PAP may be an effective agent for neurocyte injury.

Beneficial Role of Hydrogen Sulfide in Renal Ischemia Reperfusion Injury in Rats

PURPOSE

Hydrogen sulfide (H₂S) is an endogenous gaseous molecule with important physiological roles. It is synthesized from cysteine by cystathionine γ-lyase (CGL) and cystathionine β-synthase (CBS). The present study examined the benefits of exogenous H₂S on renal ischemia reperfusion (IR) injury, as well as the effects of CGL or CBS inhibition. Furthermore, we elucidated the mechanism underlying the action of H₂S in the kidneys.

MATERIALS AND METHODS

Thirty male Sprague-Dawley rats were randomly assigned to five groups: a sham, renal IR control, sodium hydrosulfide (NaHS) treatment, H₂S donor, and CGL or CBS inhibitor administration group. Levels of blood urea nitrogen (BUN), serum creatinine (Cr), renal tissue malondialdehyde (MDA), and superoxide dismutase (SOD) were estimated. Histological changes, apoptosis, and expression of mitogen-activated protein kinase (MAPK) family members (extracellular signal-regulated kinase, c-Jun N-terminal kinase, and p38) were also evaluated.

RESULTS

NaHS attenuated serum BUN and Cr levels, as well as histological damage caused by renal IR injury. Administration of NaHS also reduced oxidative stress as evident from decreased MDA, preserved SOD, and reduced apoptotic cells. Additionally, NaHS prevented renal IR-induced MAPK phosphorylation. The CGL or CBS group showed increased MAPK family activity; however, there was no significant difference in the IR control group.

CONCLUSION

Exogenous H₂S can mitigate IR injury-led renal damage. The proposed beneficial effect of H₂S is, in part, because of the anti-oxidative stress associated with modulation of the MAPK signaling pathways.

Role of Bone Morphogenetic Protein 7 (BMP7) in the Modulation of Corneal Stromal and Epithelial Cell Functions

In the cornea, healing of the wounded avascular surface is an intricate process comprising the involvement of epithelial, stromal and neuronal cell interactions. These interactions result to the release of various growth factors that play prominent roles during corneal wound healing response. Bone morphogenetic proteins (BMPs) are unique multi-functional potent growth factors of the transforming growth factor-beta (TGF-β) superfamily. Treatment of corneal epithelial cells with substance P and nerve growth factor resulted to an increase in the expression of BMP7 mRNA. Since BMP7 is known to modulate the process of corneal wound healing, in this present study, we investigated the influence of exogenous rhBMP7 on human corneal epithelial cell and stromal cell (SFs) function. To obtain a high-fidelity expression profiling of activated biomarkers and pathways, transcriptome-wide gene-level expression profiling of epithelial cells in the presence of BMP7 was performed. Gene ontology analysis shows BMP7 stimulation activated TGF-β signaling and cell cycle pathways, whereas biological processes related to cell cycle, microtubule and intermediate filament cytoskeleton organization were significantly impacted in corneal epithelial cells. Scratch wound healing assay showed increased motility and migration of BMP7 treated epithelial cells. BMP7 stimulation studies show activation of MAPK cascade proteins in epithelial cells and SFs. Similarly, a difference in the expression of claudin, Zink finger E-box-binding homeobox 1 was observed along with phosphorylation levels of cofilin in epithelial cells. Stimulation of SFs with BMP7 activated them with increased expression of α-smooth muscle actin. In addition, an elevated phosphorylation of epidermal growth factor receptor following BMP7 stimulation was also observed both in corneal epithelial cells and SFs. Based on our transcriptome analysis data on epithelial cells and the results obtained in SFs, we conclude that BMP7 contributes to epithelial-to-mesenchymal transition-like responses and plays a role equivalent to TGF-β in the course of corneal wound healing.

miR-27a protects human mitral valve interstitial cell from TNF-α-induced inflammatory injury via up-regulation of NELL-1

MicroRNAs (miRNAs) have been reported to be associated with heart valve disease, which can be caused by inflammation. This study aimed to investigate the functional impacts of miR-27a on TNF-α-induced inflammatory injury in human mitral valve interstitial cells (hMVICs). hMVICs were subjected to 40 ng/mL TNF-α for 48 h, before which the expressions of miR-27a and NELL-1 in hMVICs were altered by stable transfection. Trypan blue staining, BrdU incorporation assay, flow cytometry detection, ELISA, and western blot assay were performed to detect cell proliferation, apoptosis, and the release of proinflammatory cytokines. We found that miR-27a was lowly expressed in response to TNF-α exposure in hMVICs. Overexpression of miR-27a rescued hMVICs from TNF-α-induced inflammatory injury, as cell viability and BrdU incorporation were increased, apoptotic cell rate was decreased, Bcl-2 was up-regulated, Bax and cleaved caspase-3/9 were down-regulated, and the release of IL-1β, IL-6, and MMP-9 were reduced. NELL-1 was positively regulated by miR-27a, and NELL-1 up-regulation exhibited protective functions during TNF-α-induced cell damage. Furthermore, miR-27a blocked JNK and Wnt/β-catenin signaling pathways, and the blockage was abolished when NELL-1 was silenced. This study demonstrated that miR-27a overexpression protected hMVICs from TNF-α-induced cell damage, which might be via up-regulation of NELL-1 and thus modulation of JNK and Wnt/β-catenin signaling pathways.

TNF-α induces human neural progenitor cell survival after oxygen-glucose deprivation by activating the NF-κB pathway

Neural progenitor cell (NPC) transplantation has been shown to be beneficial in the ischemic brain. However, the low survival rate of transplanted NPCs in an ischemic microenvironment limits their therapeutic effects. Tumor necrosis factor-alpha (TNF-α) is one of the proinflammatory cytokines involved in the pathogenesis of various injuries. On the other hand, several studies have shown that TNF-α influences the proliferation, survival, and differentiation of NPCs. Our study investigated the effect of TNF-α pretreatment on human NPCs (hNPCs) under ischemia-related conditions in vitro. hNPCs harvested from fetal brain tissue were pretreated with TNF-α before being subjected to oxygen–glucose deprivation (OGD) to mimic ischemia in vitro. TNF-α pretreatment improved the viability and reduced the apoptosis of hNPCs after OGD. At the molecular level, TNF-α markedly increased the level of NF-κB signaling in hNPCs, and an NF-κB pathway inhibitor, BAY11-7082, completely reversed the protective effects of TNF-α on hNPCs. These results suggest that TNF-α improves hNPC survival by activating the NF-κB pathway. In addition, TNF-α significantly enhanced the expression of cellular inhibitor of apoptosis 2 (cIAP2). Use of a lentivirus-mediated short hairpin RNA targeting cIAP2 mRNA demonstrated that cIAP2 protected against OGD-induced cytotoxicity in hNPCs. Our study of intracellular NF-κB signaling revealed that inhibition of NF-κB activity abolished the TNF-α-mediated upregulation of cIAP2 in hNPCs and blocked TNF-α-induced cytoprotection against OGD. Therefore, this study suggests that TNF-α pretreatment, which protects hNPCs from OGD-induced apoptosis by activating the NF-κB pathway, provides a safe and simple approach to improve the viability of transplanted hNPCs in cerebral ischemia.

A potent “survival signal” for brain stem cells could enable effective regenerative therapies for stroke patients. Neural progenitor cells (NPCs) can develop into functional neurons and supportive glial cells, and researchers are tantalized by the prospect of using NPCs to repair damaged brain tissue. NPCs generally fail to flourish after transplantation, but a team led by Kook In Park at Yonsei University College of Medicine, South Korea, have found a signaling factor that helps these cells to survive and divide. Tumor necrosis factor-α (TNF-α) is associated with inflammation, but also protects neurons after a stroke. The researchers showed that pretreatment with TNF-α preserved NPCs exposed to starvation and oxygen-deprivation conditions in cell culture by activating critical cell survival pathways. These findings suggest that TNF-α may enable NPCs to survive long enough to repair post-stroke neurological damage.