Mitogen-activated Protein Kinase Signaling Pathway Research Articles

Genetic variability of maize (Zea mays) germplasm from Iran: genotyping with a maize 600K SNP array and genome-wide scanning for selection signatures

Context Maize (Zea mays L.) is one of the most economically important plants of the cereal family; it has value as human food, livestock feed, and as a component of industrial products. Aims This study focused on genetic diversity and existence of genetic divergence among promising maize inbred lines in Iran. Methods A commercial maize 600K SNP (single-nucleotide polymorphism) array was used to inspect genetic variability among 93 maize inbred lines. Key results The rate of transition mutation was twice as high as transversion mutation, and the density of detected SNPs was greater close to telomere regions of maize chromosomes. Considering the fluctuation of observed, expected and total heterozygosity and fixation index values across maize chromosomes, as well as polymorphism information content values, there is a high level of genetic variability among the studied maize panel. In addition, discriminant analysis of the principal components revealed four subpopulations in which the subpopulation ‘Line’ was distinct from other subpopulations and had no genomic overlap with them. Selection signature analysis revealed 177 regions harbouring 75 genes that differentiate among subgroups. Detected genes had a role in the mitogen-activated protein kinase signalling pathway, spliceosome, protein processing in endoplasmic reticulum, and hormone signal transduction. Conclusions We conclude that remarkable genetic diversity and differentiation exists among the studied maize subpopulations. The most differentiated SNPs among the subpopulations were associated with important biological processing genes and pathways. Implications The findings provide valuable insights for future maize breeding programs through exploitation of heterosis, as well as marker-assisted selection.

Protective Effects of Carbonated Chitosan Montmorillonite on Vomitoxin-Induced Intestinal Inflammation.

Exposure to vomitoxin (DON) can negatively impact the intestinal health of livestock and poultry, leading to compromised nutrient absorption and utilization, resulting in slowed growth and reduced production efficiency. In this study, we synthesized carbonated chitosan montmorillonite intercalation complexes (CCM) through solution precipitation. The successful formation of intercalation complexes was confirmed by examining functional groups and surface features using infrared spectroscopy and scanning electron microscopy. To assess the impact of CCM on DON-infected mice, we established an experimental mouse model of jejunal inflammation induced by DON infection. We analyzed the effects of CCM on blood biochemical and conventional indices, jejunal inflammatory factors, pathological changes, and the expression of proteins in the MAPK pathways in DON-infected mice. Our results indicate that CCM effectively mitigates the adverse effects of DON on growth performance, jejunal injury, and the inflammatory response in mice. CCM supplementation alleviated the negative effects of DON infection on growth performance and reduced intestinal inflammation in mice. Moreover, CCM supplementation successfully inhibited the activation of the mitogen-activated protein kinase (MAPK) signaling pathway induced by DON. These findings suggest that the mitigating effect of CCM on DON-induced inflammatory injury in the murine jejunum is closely linked to the regulation of the MAPK signaling pathway.

Integrated Serum Pharmacochemistry and Network Pharmacological Analysis Used To Explore Possible Anti-Aging Mechanisms of the Ginsenosides

Although constitutive ginsenosides are credited with ginseng's remarkable anti-aging efficacy, the mechanism of action and bioactive components of ginsenosides are unclear. The goal of the study was to examine the effect of ginsenosides on D-galactose (D-gal)-induced aging in rats and to figure out the underlying molecular mechanism using serum pharmacochemistry and network pharmacology. Using behavioral, biochemical indexes, and histological analysis, ginsenosides were evaluated for their anti-aging effects in rats induced by D-gal, and effective ingredients absorbed in the blood were examined by ultra-performance liquid chromatography quadrupole time of flight coupled with mass spectrometry (UPLC-Q/TOF-MS) before being subjected to network pharmacology analysis. As well as improving spatial learning and memory skills, Ginsenosides are known to regulate malondialdehyde (MDA), glutathione peroxidase (GSH-Px), total antioxidant capacity (T-AOC) and superoxide dismutase (SOD) activity. In addition, it improved the ultrastructure of neurons in D-gal-induced rats' hippocampus. Seventy-four absorption components and metabolites of ginsenosides were identified in aging rat serum. According to a network pharmacology study, ginsenosides have anti-aging properties by modulating the phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) and mitogen-activated protein kinases (MAPK) signaling pathways. The potential mechanisms of the anti-aging effect of ginsenosides involve multiple components, targets, and pathways. These findings serve as a foundation for further research into the processes behind ginsenoside's anti-aging impact.

Down-regulation of MKP-1 in hippocampus protects against stress-induced depression-like behaviors and neuroinflammation

Chronic stress is the primary environmental risk factor for major depressive disorder (MDD), and there is compelling evidence that neuroinflammation is the major pathomechanism linking chronic stress to MDD. Mitogen-activated protein kinase (MAPK) phosphatase-1 (MKP-1) is a negative regulator of MAPK signaling pathways involved in cellular stress responses, survival, and neuroinflammation. We examined the possible contributions of MKP-1 to stress-induced MDD by comparing depression-like behaviors (anhedonia, motor retardation, behavioral despair), neuroinflammatory marker expression, and MAPK signaling pathways among rats exposed to chronic unpredictable mild stress (CUMS), overexpressing MKP-1 in the hippocampus, and CUMS-exposed rats underexpressing MKP-1 in the hippocampus. Rats exposed to CUMS exhibited MKP-1 overexpression, greater numbers of activated microglia, and enhanced expressions of neuroinflammatory markers (interleukin [IL]-6, [IL]-1β, tumor necrosis factor [TNF]-ɑ, and decreased phosphorylation levels of ERK and p38 in the hippocampus as well as anhedonia in the sucrose preference test, motor retardation in the open field, and greater immobility (despair) in the forced swimming tests. These signs of neuroinflammation and depression-like behaviors and phosphorylation levels of ERK and p38 were also observed in rats overexpressing MKP-1 without CUMS exposure, while CUMS-induced neuroinflammation, microglial activation, phosphorylation levels of ERK and p38, and depression-like behaviors were significantly reversed by MKP-1 knockdown. Moreover, MKP-1 knockdown promoted the activation of the MAPK isoform ERK, implying that the antidepressant-like effects of MKP-1 knockdown may be mediated by the ERK pathway disinhibition. These findings suggested that hippocampal MKP-1 is an essential regulator of stress-induced neuroinflammation and a promising target for antidepressant development.

Caffeic acid-grafted chitooligosaccharides downregulate MAPK and NF-kB in RAW264.7 cells.

Chitooligosaccharide (COS) is a derivative of chitosan, which is a natural macromolecular compound. COS has been shown effects in an inflammatory response. Recent reports show that COS derivatives have enhanced anti-inflammatory activity by inhibiting intracellular signals. Evaluation of the anti-inflammatory effect of caffeic acid conjugated COS chain (CA-COS) was performed in this study. The effects of CA-COS on the inflammatory response were demonstrated in lipopolysaccharide-stimulated RAW264.7 macrophages. The results showed that CA-COS inhibited nitric oxide (NO) production and downregulated the gene expression of nitric oxide synthase (iNOS), and cytokines such as tumor necrosis factor-alpha (TNF-α), IL-1β, and IL-6 without cytotoxic effect. In addition, western blot analysis showed that CA-COS inhibits the protein expression of iNOS and nuclear factor kappa B (NF-kB), including p50 and p65, and mitogen-activated protein kinase (MAPK) signaling pathways. Collectively, these results provide clear evidence for the anti-inflammatory mechanism of CA-COS that show great potential as a novel agent for the prevention and therapy of inflammatory diseases.

Mechanism of electroconvulsive therapy in schizophrenia: a bioinformatics analysis study of RNA-seq data.

The molecular mechanism of electroconvulsive therapy (ECT) for schizophrenia remains unclear. The aim of this study was to uncover the underlying biological mechanisms of ECT in the treatment of schizophrenia using a transcriptional dataset. The peripheral blood mRNA sequencing data of eight patients (before and after ECT) and eight healthy controls were analyzed by integrated co-expression network analysis and the differentially expressed genes were analyzed by cluster analysis. Gene set overlap analysis was performed using the hypergeometric distribution of phypfunction in R. Associations of these gene sets with psychiatric disorders were explored. Tissue-specific enrichment analysis, gene ontology enrichment analysis, and protein-protein interaction enrichment analysis were used for gene set organization localization and pathway analysis. We found the genes of the green-yellow module were significantly associated with the effect of ECT treatment and the common gene variants of schizophrenia ( P = 0.0061; family-wise error correction). The genes of the green-yellow module are mainly enriched in brain tissue and mainly involved in the pathways of neurotrophin, mitogen-activated protein kinase and long-term potentiation. Genes associated with the efficacy of ECT were predominantly enriched in neurotrophin, mitogen-activated protein kinase and long-term potentiation signaling pathways.

Incomplete immunity in a natural animal-microbiota interaction selects for higher pathogen virulence

Incomplete immunity in recovered hosts is predicted to favor more virulent pathogens upon re-infection in the population.1 The microbiota colonizing animals can generate a similarly long-lasting, partial immune response, allowing for infection but dampened disease severity.2 We tracked the evolutionary trajectories of a widespread pathogen (Pseudomonas aeruginosa), experimentally passaged through populations of nematodes immune-primed by a natural microbiota member (P.berkeleyensis). This bacterium can induce genes regulated by a mitogen-activated protein kinase (MAPK) signaling pathway effective at conferring protection against pathogen-induced death despite infection.3 Across host populations, this incomplete immunity selected for pathogens more than twice as likely to kill as those evolved in non-primed (i.e., naive) or immune-compromised (mutants with a knockout of the MAPK ortholog) control populations. Despite the higher virulence, pathogen molecular evolution in immune-primed hosts was slow and constrained. In comparison, evolving pathogens in immune-compromised hosts were characterized by substantial genomic differentiation and attenuated virulence. These findings directly attribute the incomplete host immunity induced from microbiota as a significant force shaping the virulence and evolutionary dynamics of novel infectious diseases.

Unraveling the Dual Inhibitory Mechanism of Compound 22ac: A Molecular Dynamics Investigation into ERK1 and ERK5 Inhibition in Cancer

Cancer remains a major challenge in the field of medicine, necessitating innovative therapeutic strategies. Mitogen-activated protein kinase (MAPK) signaling pathways, particularly Extracellular Signal-Regulated Kinase 1 and 2 (ERK1/2), play pivotal roles in cancer pathogenesis. Recently, ERK5 (also known as MAPK7) has emerged as an attractive target due to its compensatory role in cancer progression upon termination of ERK1 signaling. This study explores the potential of Compound 22ac, a novel small molecule inhibitor, to simultaneously target both ERK1 and ERK5 in cancer cells. Using molecular dynamics simulations, we investigate the binding affinity, conformational dynamics, and stability of Compound 22ac when interacting with ERK1 and ERK5. Our results indicate that Compound 22ac forms strong interactions with key residues in the ATP-binding pocket of both ERK1 and ERK5, effectively inhibiting their catalytic activity. Furthermore, the simulations reveal subtle differences in the binding modes of Compound 22ac within the two kinases, shedding light on the dual inhibitory mechanism. This research not only elucidates a structural mechanism of action of Compound 22ac, but also highlights its potential as a promising therapeutic agent for cancer treatment. The dual inhibition of ERK1 and ERK5 by Compound 22ac offers a novel approach to disrupting the MAPK signaling cascade, thereby hindering cancer progression. These findings may contribute to the development of targeted therapies that could improve the prognosis for cancer patients.

Effect of Calebin-A on Critical Genes Related to NAFLD: A Protein-Protein Interaction Network and Molecular Docking Study.

Calebin-A is a minor phytoconstituent of turmeric known for its activity against inflammation, oxidative stress, cancerous, and metabolic disorders like Non-alcoholic fatty liver disease(NAFLD). Based on bioinformatic tools. Subsequently, the details of the interaction of critical proteins with Calebin-A were investigated using the molecular docking technique. We first probed the intersection of genes/ proteins between NAFLD and Calebin-A through online databases. Besides, we performed an enrichment analysis using the ClueGO plugin to investigate signaling pathways and gene ontology. Next, we evaluate the possible interaction of Calebin-A with significant hub proteins involved in NAFLD through a molecular docking study. We identified 87 intersection genes Calebin-A targets associated with NAFLD. PPI network analysis introduced 10 hub genes (TP53, TNF, STAT3, HSP90AA1, PTGS2, HDAC6, ABCB1, CCT2, NR1I2, and GUSB). In KEGG enrichment, most were associated with Sphingolipid, vascular endothelial growth factor A (VEGFA), C-type lectin receptor, and mitogen-activated protein kinase (MAPK) signaling pathways. The biological processes described in 87 intersection genes are mostly concerned with regulating the apoptotic process, cytokine production, and intracellular signal transduction. Molecular docking results also directed that Calebin-A had a high affinity to bind hub proteins linked to NAFLD. Here, we showed that Calebin-A, through its effect on several critical genes/ proteins and pathways, might repress the progression of NAFLD.

Investigation of the Mechanism of Action of Qingzaojiufei Decoction on Idiopathic Pulmonary Fibrosis Based on Network Pharmacology and Experimental Validation

Objective: The Traditional Chinese Medicine Qingzao Jiufei Tang decoction (QZJFD) is effective for the treatment of idiopathic pulmonary fibrosis (IPF). In this study, we explored the anti-pulmonary fibrosis effect of QZJFD and the underlying mechanism. Methods: The effects of QZJFD at low, medium, and high doses were investigated in a rat model of lung fibrosis induced by tracheal injection of bleomycin; pirfenidone was included as a positive control. Serum levels of interleukin-6 (IL-6), tumor necrosis factors (TNF-α), and IL-1β in rats were detected by enzyme-linked immunosorbent assay (ELISA). Expression of α-smooth muscle actin (α-SMA), TGF-β1, p-Jun N-terminal kinase (p-JNK), JNK, p-P38 mitogen-activated protein kinase (MAPK), P38 MAPK, collagen I, and fibronectin-1 (FN1) in lung tissues was detected by immunofluorescence labeling and western blot analysis. Results: QZJFD contained 209 main components and 575 corresponding targets. In total, 3875 disease action targets were related to IPF, with 308 common targets shared by drugs and diseases. The key targets included albumin (ALB), recombinant protein, TNF, IL-6, and tumor protein p53. In total, 3061 items were identified in the gene ontology enrichment analysis ( P < .05) and 197 signaling pathways in the Kyoto encyclopedia of genes and genomes ( P < .05), including MAPK, calcium, advanced glycosylation end products - receptors, TNF, and IL-17. Molecular docking simulation showed that the 2 predominant compounds of QZJFD, naringenin, and kaempferol, bound with high affinity to ALB. Serum levels of IL-6, TNF-α, and IL-1β and the expression levels of α-SMA, TGF-β1, p-JNK, p-P38 MAPK, collagen I, and FN1 in lung tissues were significantly increased in the model rats ( P < .001). After treatment with pirfenidone and QZJFD at the medium and high doses, serum levels of IL-6, TNF-α, and IL-1β and expression levels of α-SMA, p-JNK, p-P38 MAPK, collagen I, and FN1 in lung tissues of rats were significantly lower than those in the model group ( P < .05). Conclusions: QZJFD may exert antifibrotic and anti-inflammatory effects that improve the status of IPF by regulating the MAPK signaling pathway.

Emerging Roles of Mitogen-Activated Protein Kinase Signaling Pathways in the Regulation of Fruit Ripening and Postharvest Quality.

Fleshy fruit ripening is a unique biological process that involves dramatic changes in a diverse array of cellular metabolisms. The regulation of these metabolisms is essentially mediated by cellular signal transduction of internal (e.g., hormones) and external cues (i.e., environmental stimuli). Mitogen-activated protein kinase (MAPK) signaling pathways play crucial roles in a diverse array of biological processes, such as plant growth, development and biotic/abiotic responses. Accumulating evidence suggests that MAPK signaling pathways are also implicated in fruit ripening and quality formation. However, while MAPK signaling has been extensively reviewed in Arabidopsis and some crop plants, the comprehensive picture of how MAPK signaling regulates fruit ripening and quality formation remains unclear. In this review, we summarize and discuss research in this area. We first summarize recent studies on the expression patterns of related kinase members in relation to fruit development and ripening and then summarize and discuss the crucial evidence of the involvement of MAPK signaling in fruit ripening and quality formation. Finally, we propose several perspectives, highlighting the research matters and questions that should be afforded particular attention in future studies.

Integrated analysis of long non-coding RNAs and mRNAs associated with condyloma acuminatum.

Condyloma acuminatum (CA) is a prevalent sexually transmitted disease caused by low-risk human papillomavirus infection, characterized by high transmission and recurrence rates. Long non-coding RNAs (lncRNAs) play a crucial role in regulating gene transcription and are involved in various biological processes. Although recent studies have demonstrated the involvement of lncRNAs in cervical cancer, their expression profile and function in CA remain poorly understood. In this study, we aimed to identify messenger RNA (mRNA) and lncRNA expression patterns in CA using high-throughput lncRNA sequencing. We found that 3033 differentially expressed genes (DEGs) and 1090 differentially expressed lncRNAs (DELs) were significantly altered in CA compared to healthy controls. The results from quantitative reverse transcription polymerase chain reaction and immunohistochemical staining are in accordance with the observed trends in the sequencing data. Functional enrichment analysis revealed that upregulated DEGs in CA were involved in biological processes such as virus response, immune response, cell cycle regulation, the tumor necrosis factor signaling pathway, and the P53 signaling pathway. Co-expression network analysis identified potential target genes of DELs, with enrichment in biological processes such as cell differentiation, the intrinsic apoptotic signaling pathway, and pathways such as virus infection, pathways in cancer, T helper 17 cell differentiation, the mitogen-activated protein kinase signaling pathway, and the Wnt signaling pathway. Collectively, our findings indicate significant changes in the transcriptome profile, including mRNAs and lncRNAs, in CA compared to healthy controls. Our study provides new insights into the potential functions of lncRNAs in the pathogenesis of CA and identifies potential therapeutic targets for this disease.

Methyl Jasmonate-induced Increase in Intracellular Magnesium Promotes Apoptosis in Breast Cancer Cells.

Methyl jasmonate (MeJa) is a botanical stress hormone that serves as a defense mechanism to inhibit growth in stressed plants. It is well known that MeJa exhibits an anticancer effect by reducing intracellular ATP, activating reactive oxygen species (ROS) production, and promoting mitogen-activated protein kinase (MAPK) activity. Presently, no report has been published on MeJa-induced changes in intracellular Mg2+ concentration ([Mg2+]i), and TRPM7 as an Mg2+ transporter in cancer cells. Therefore, this study aimed to investigate the Mg2+ homeostatic changes and apoptotic effects following MeJa treatment using the MCF-7 human breast cancer cell line. The MTT assay was used to assess the cell viability and half-inhibitory concentration, microscopic two-photon excitation wavelength spectrophotometry was used to measure the [Mg2+]i, a luminescent assay determined intracellular ATP levels, western blot assay measured TRPM7 levels, antioxidant capacities, endoplasmic reticulum (ER) stress, and MAPK signaling pathways, while the fluorescence assay evaluated ROS concentrations and the cell apoptotic index. This study provides evidence that MeJa has an antiapoptotic effect on MCF-7 cells. The increase in [Mg2+]i led to decreased TRPM7 expression, which is related to elevated ROS production, in addition to elevated ER stress and MAPK signaling pathway activity and decreased ATP content. The increase in [Mg2+]i leads to decreased TRPM7 expression and may be the epicenter of MeJa-induced apoptotic cell death in MCF-7 cells.

Punicalagin promotes mincle-mediated phagocytosis of macrophages via the NF-κB and MAPK signaling pathways

Punicalagin (PUN) is a polyphenol derived from the pomegranate peel. It has been reported to have many beneficial effects, including anti-inflammatory, anti-oxidant, and anti-proliferation. However, the role of PUN in macrophage phagocytosis is currently unknown. In this study, we found that pre-treatment with PUN significantly enhanced phagocytosis by macrophages in a time- and dose-dependent manner in vitro. Moreover, KEGG enrichment analysis by RNA-sequencing showed that differentially expressed genes following PUN treatment were significantly enriched in phagocyte-related receptors, such as the C-type lectin receptor signaling pathway. Among the C-type lectin receptor family, Mincle (Clec4e) significantly increased at the mRNA and protein level after PUN treatment, as shown by qRT-PCR and western blotting. Small interfering RNA (siRNA) mediated knockdown of Mincle in macrophages resulted in down regulation of phagocytosis. Furthermore, western blotting showed that PUN treatment enhanced the phosphorylation of nuclear factor kappa-B (NF-κB) and mitogen-activated protein kinase (MAPK) in macrophages at the early stage. Mincle-mediated phagocytosis by PUN was inhibited by PDTC (a NF-κB inhibitor) and SB203580 (a p38 MAPK inhibitor). In addition, PUN pre-treatment enhanced phagocytosis by peritoneal and alveolar macrophages in vivo. After intraperitoneal injection of Escherichia coli (E.coli), the bacterial load of peritoneal lavage fluid and peripheral blood in PUN pre-treated mice decreased significantly. Similarly, the number of bacteria in the lung tissue significantly reduced after intranasal administration of Pseudomonas aeruginosa (PAO1). Taken together, our results reveal that PUN enhances bacterial clearance in mice by activating the NF-κB and MAPK pathways and upregulating C-type lectin receptor expression to enhance phagocytosis by macrophages.

Long- and short-term dietary β-glucan improves intestinal health and disease resistance in pearl gentian grouper (Epinephelus lanceolatus♂ × Epinephelus fuscoguttatus♀).

β-Glucans are immunostimulants and are widely used in aquaculture industry. The present study was conducted to evaluate the effects of different periods of β-glucan management on growth performance, intestinal health, and disease resistance in pearl gentian grouper (Epinephelus lanceolatus♂ × Epinephelus fuscoguttatus♀). A commercial feed was used as control diet (CD), and the β-glucan diet (βD) was based on CD and further supplemented with 0.1% β-glucan. Grouper in control and long-term β-glucan diet (LGD) groups were fed with CD and βD for 8 weeks, respectively. Groupers in short-term β-glucan diet (SGD) group were fed with CD for the first 4 weeks and βD for the last 4 weeks. We found that LGD and SGD had no effect on growth performance but reduced the mortalities of grouper after challenging with Vibrio harveyi. In addition, both LGD and SGD increased intestinal morphology, enhanced antioxidant capacity, enhanced immunity, inhibited apoptosis, altered the transcriptional profile, and activated mitogen-activated protein kinase (MAPK) and nuclear factor kappa-B (NF-κB) signaling pathway in the intestine of grouper. Furthermore, the effect of LGD on most of the above parameters was comparable to that of SGD. In conclusion, LGD and SGD did not affect growth rate parameters but enhanced the intestinal health and disease resistance of pearl gentian grouper.

Edgeworthia gardneri (Wall.) Meisn. Ethanolic Extract Attenuates Endothelial Activation and Alleviates Cardiac Ischemia-Reperfusion Injury.

Endothelial pro-inflammatory activation is pivotal in cardiac ischemia-reperfusion (I/R) injury pathophysiology. The dried flower bud of Edgeworthia gardneri (Wall.) Meisn. (EG) is a commonly utilized traditional Tibetan medicine. However, its role in regulating endothelium activation and cardiac I/R injury has not been investigated. Herein, we showed that the administration of EG ethanolic extract exhibited a potent therapeutic efficacy in ameliorating cardiac endothelial inflammation (p < 0.05) and thereby protecting against myocardial I/R injury in rats (p < 0.001). In line with the in vivo findings, the EG extract suppressed endothelial pro-inflammatory activation in vitro by downregulating the expression of pro-inflammatory mediators (p < 0.05) and diminishing monocytes' firm adhesion to endothelial cells (ECs) (p < 0.01). Mechanistically, we showed that EG extract inhibited the nuclear factor kappa-B (NF-κB), c-Jun N-terminal kinase (JNK), extracellular regulated protein kinase (ERK), and p38 mitogen-activated protein kinase (MAPK) signaling pathways to attenuate EC-mediated inflammation (p < 0.05). Collectively, for the first time, this study demonstrated the therapeutic potential of EG ethanolic extract in alleviating I/R-induced inflammation and the resulting cardiac injury through its inhibitory role in regulating endothelium activation.

Icariin regulates RANKL-induced osteoclast differentiation via the ERα/c-Src/RANK signaling

Osteoporosis (OP) is a common metabolic bone disease. Excessive osteoclastic activity significantly contributes to the development of OP. Icariin (ICA) is a flavonol glycoside derived from herbal plants and possesses curative effects on postmenopausal OP and bone fracture. This study aimed to investigate the effects of ICA on osteoclast differentiation induced by receptor activator of nuclear factor kappa B (RANK) ligand (RANKL) and the involvement of estrogen receptor α (ERα) and RANK signaling cascade in this process. RANKL was used to induce the differentiation of RAW264.7 cells to into osteoclasts. Small interfering RNA technique was used to knockdown ERα in cells. Cell counting kit-8 assay was performed to determine the cytotoxicity of ICA. The number of tartrate-resistant acid phosphatase (TRAP)-positive cells was quantified by TRAP staining. RANKL induced the differentiation of RAW264.7 cells into osteoclasts, while ICA abolished the pro-osteoporotic effect of RANKL. Moreover, ERα knockdown abolished the effects of ICA on RANKL-induced osteoclastogenesis. Further exploration revealed that ICA inhibited the phosphorylation of c-Src in osteoclasts via regulating ERα, while inactivation of c-Src reversed ERα knockdown-promoted osteoclastogenesis. Lastly, ICA inhibited the activation of the mitogen-activated protein kinase signaling pathway and downregulated the expressions of target osteoclastogenic proteins in RANKL-treated RAW 264.7 cells, while ERα knockdown almost completely diminished the effects of ICA. ICA inhibited RANKL-induced osteoclast differentiation via regulating the ERα/c-Src/RANK signaling. These findings elucidated a novel mechanism by which ICA exerts an anti-osteoporotic effect.

Antibody targeting of surface P-selectin glycoprotein ligand 1 leads to lymphoma apoptosis and tumorigenesis inhibition.

Lymphomas are a heterogeneous group of diseases that originate from T, B or natural killer cells. Lymphoma treatment is based on chemotherapy, radiotherapy, and monoclonal antibody (mAb) or other immunotherapies. The P-selectin glycoprotein ligand 1 (PSGL-1) is expressed at the surface of hematological malignant cells and has been shown to have a pro-oncogenic role in multiple myeloma and lymphoma. Here, we investigated the expression and therapeutic potential of PSGL-1 in T and B cell lymphomas. By flow cytometry analysis, we found that PSGL-1 was expressed in both T and B cell-derived lymphoma cell lines but generally at higher levels in T cell lymphoma cell lines. For most T and B cell-derived lymphoma cell lines, in vitro targeting with the PL1 mAb, which recognizes the PSGL-1 N-terminal extracellular region and blocks functional interactions with selectins, resulted in reduced cell viability. The PL1 mAb pro-apoptotic activity was shown to be dose-dependent, to be linked to increased ERK kinase phosphorylation, and to be dependent on the MAP kinase signaling pathway. Importantly, anti-PSGL-1 treatment of mice xenografted with the HUT-78 cutaneous T-cell lymphoma cell line resulted in decreased tumor growth, had no effect on in vivo proliferation, but increased the levels of apoptosis in tumors. Anti-PSGL-1 treatment of mice xenografted with a Burkitt lymphoma cell line that was resistant to anti-PSGL-1 treatment in vitro, had no impact on tumorigenesis. These findings show that PSGL-1 antibody targeting triggers lymphoma cell apoptosis and substantiates PSGL-1 as a potential target for lymphoma therapy.

Inhibitory Effects of Eicosapentaenoic Acid on Vascular Endothelial Growth Factor-Induced Monocyte Chemoattractant Protein-1, Interleukin-6, and Interleukin-8 in Human Vascular Endothelial Cells.

Vascular endothelial growth factor (VEGF) induces monocyte chemoattractant protein-1 (MCP-1) and plays an important role in vascular inflammation and atherosclerosis. We investigated the mechanisms of VEGF-induced MCP-1 expression and the effects of eicosapentaenoic acid (EPA) in human umbilical vein endothelial cells (HUVECs). Real-time reverse transcription polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) demonstrated that VEGF enhanced MCP-1 gene expression and protein secretion in HUVECs. Western immunoblot analysis revealed that VEGF induced the phosphorylation of p38 mitogen-activated protein kinase (MAPK) and inhibitor of nuclear factor (NF)-κB (IκB). Treatment with pharmacological inhibitors of p38 MAPK (SB203580) or NF-κB (BAY11-7085) significantly suppressed VEGF-induced MCP-1 in HUVECs. EPA inhibited VEGF-induced MCP-1 mRNA, protein secretion, phosphorylation of p38 MAPK, and the translocation of phospho-p65 to the nucleus. Additionally, VEGF also stimulated gene expressions of interleukin (IL)-6 and IL-8, which were suppressed by SB203580, BAY11-7085, and EPA. The present study has demonstrated that VEGF-induced activation of MCP-1, IL-6, and IL-8 involves the p38 MAPK and NF-κB signaling pathways and that EPA inhibits VEGF-induced MCP-1, IL-6, and IL-8 via suppressing these signaling pathways. This study supports EPA as a beneficial anti-inflammatory and anti-atherogenic drug to reduce the VEGF-induced activation of proinflammatory cytokine and chemokines.

Network pharmacology analysis and experimental verification of the antitumor effect and molecular mechanism of isocryptomerin on HepG2 cells.

Isocryptomerin (ISO) is a flavonoid isolated from the natural medicine Selaginellae Herba, which has various pharmacological activities. This study investigated the antitumor effect and underlying molecular mechanism of ISO on hepatocellular carcinoma (HCC) HepG2 cells. The cell viability assay revealed that ISO has a considerable killing effect on HCC cell lines. The apoptosis assay showed that ISO induced mitochondria-dependent apoptosis through the Bad/cyto-c/cleaved (cle)-caspase-3/cleaved (cle)-PARP pathway. The network pharmacological analysis found 13 key target genes, and epidermal growth factor receptor (EGFR), AKT, mitogen-activated protein kinase(MAPK), and reactive oxygen species (ROS) signaling pathways were strongly associated with ISO against HCC. Further verification of the results showed that ISO induced apoptosis by increasing p-p38 and p-JNK expression and decreasing p-EGFR, p-SRC, p-ERK, and p-STAT3 expression. Furthermore, ISO induced G0/G1 phase arrest by downregulating p-AKT, Cyclin D, and CDK 4 expression and upregulating p21 and p27 expression in HepG2 cells. Moreover, ISO inhibited HepG2 cell migration by decreasing p-GSK-3β, β-catenin, and N-cadherin expression and increasing E-cadherin expression. Additionally, ISO promoted ROS accumulation in HepG2 cells, and ISO-induced apoptosis, arrest cell cycle, and inhibition of migration were reversed by an ROS scavenger, N-acetyl- l-cysteine. Overall, ISO induced cell apoptosis and cell cycle arrest and inhibited cell migration by ROS-mediated EGFR, AKT, and MAPK signaling pathways in HepG2 cells.