P38 Mitogen-activated Protein Kinase Inhibitor Research Articles

Involvement of Sep38β in the Insecticidal Activity of Bacillus thuringiensis against Beet Armyworm, Spodoptera exigua (Lepidoptera).

The p38 mitogen-activated protein kinases (MAPKs) are associated with insect immunity, tissue repair, and the insecticidal activity of Bacillus thuringiensis (Bt). Here, a p38 MAPK family gene (Sep38β) was identified from Spodoptera exigua. Among the developmental stages, the transcription level of Sep38β was the highest in egg, followed by that in prepupa and pupa. Sep38β expression peaked in Malpighian tubules and the hemolymph of fifth instar larvae. Knockdown of Sep38β or injection of SB203580 (a p38 MAPK inhibitor) significantly downregulated the SeDUOX expression and reactive oxygen species (ROS) level in the midgut, accounting for deterioration of the midgut to scavenge pathogens and enhancement of Bt insecticidal activity. In conclusion, all the results demonstrate that Sep38β regulates the immune-related ROS level in the insect midgut, which suppresses the insecticidal activity of Bt against S. exigua by 17-22%. Our study highlights that Sep38β is essential for insect immunity and the insecticidal activity of Bt to S. exigua and is a potential target for pest control.

Insights into cAMP-dependent molecular mechanisms regulating expression and function of LGALS16 gene in choriocarcinoma JEG-3 cells.

The human choriocarcinoma cell line JEG-3 offers a valuable model to study galectin-16 gene (LGALS16) expression and functions in the context of placental cell differentiation and cancer cell biology. Recent evidence indicates that cAMP-mediated signaling pathways might be responsible for the upregulation of LGALS16; however, the underlying mechanisms are unknown. Here, we employed biochemical inhibitors of the cAMP cascade and CRISPR/Cas9 engineered cells to assess regulatory patterns and associations between cAMP-induced trophoblast differentiation and LGALS16 expression in JEG-3 cells. The expression of LGALS16 was significantly upregulated in parallel with human chorionic gonadotropin beta (CGB), a biomarker of syncytiotrophoblast differentiation, in response to 8-Br-cAMP. Inhibition of p38 MAPK and EPAC significantly altered LGALS16 expression during differentiation, while PKA inhibition failed to change LGALS16 and CGB3/5 expression in our cell model. The CRISPR/Cas9 LGALS16 knockout cell pool expressed a significantly lower amount of CGB3/5, a reduced level of CGB protein, and an unaltered cell growth rate in response to 8-Br-cAMP in comparison with wild-type JEG-3 cells. Collectively, these findings suggest that LGALS16 is required for the trophoblast-like differentiation of JEG-3 cells, and its expression is mediated through p38 MAPK and EPAC signaling pathway branches.

Total Glucosides of Paeony Induce Mitochondrial Dysfunction and Apoptosis by Promoting the Degradation of α5-nAChR in Melanoma Cells.

Malignant melanoma is the leading cause of skin cancer-related death, with high malignancy and rapid progression. Total glucosides of paeony (TGP) are extracted from the roots of Paeonia Lactiflora Pall and are widely used in the treatment of chronic hepatitis, rheumatoid arthritis, and adjuvant therapy of tumor chemotherapy. In the present research, M14 and A375 cells were treated with TGP. CCK8, transwell and western blotting were performed to analyze the effect of TGP on cell function. TGP treatment impeded the proliferation and migration and activated the apoptosis pathway in melanoma cells. Importantly, TGP induced the degradation of α5-nAChR. Overexpression of α5-nAChR inhibited the anti-cancer effect of TGP. In addition, TGP treatment released cytochrome c from mitochondria into the cytoplasm, inducing mitochondrial dysfunction in melanoma cells. TGP also inhibited the phosphorylation of P38-MAPK, and P38-MAPK inhibitor reduced the promoting effect of α5-nAChR in cell proliferation and migration. TGP inhibited cell viability and migration and induced mitochondrial dysfunction and apoptosis by promoting the degradation of α5-nAChR in melanoma cells. This research provided a potential therapeutic anti-cancer drug for treatment strategies of melanoma.

Transforming growth factor-β1 protects against white matter injury and reactive astrogliosis via the p38 MAPK pathway in rodent demyelinating model.

In central nervous system (CNS), demyelination is a pathological process featured with a loss of myelin sheaths around axons, which is responsible for the diseases of multiple sclerosis, neuromyelitis optica, and so on. Transforming growth factor-beta1 (TGF-β1) is a multifunctional cytokine participating in abundant physiological and pathological processes in CNS. However, the effects of TGF-β1 on CNS demyelinating disease and its underlying mechanisms are controversial and not well understood. Herein, we evaluated the protective potential of TGF-β1 in a rodent demyelinating model established by lysophosphatidylcholine (LPC) injection. It was identified that supplement of TGF-β1 evidently rescued the cognitive deficit and motor dysfunction in LPC modeling mice assessed by novel object recognition and balance beam behavioral tests. Besides, quantified by luxol fast blue staining, immunofluorescence, and western blot, administration of TGF-β1 was found to significantly ameliorate the demyelinating lesion and reactive astrogliosis by suppressing p38 MAPK pathway. Mechanistically, the results of invitro experiments indicated that treatment of TGF-β1 could directly promote the differentiation and migration of cultured oligodendrocytes. Our study revealed that modulating TGF-β1 activity might serve as a promising and innovative therapeutic strategy in CNS demyelinating diseases.

Baicalin Promotes Apoptosis of Human Medullary Breast Cancer via the ERK/p38 MAPK Pathway

Objectives The present study aims to examine the effects of baicalin on the human medullary breast carcinoma (MBC) cell line Bcap-37 and to determine whether baicalin regulates Bcap-37 cell apoptosis through the ERK/p38 mitogen-activated protein kinase (MAPK) signaling pathway. Materials and Methods 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and Transwell assay were utilized to measure the effects of baicalin on the proliferation and migration ability of Bcap-37 cells, respectively. Flow cytometer analysis was implied to detect the effects of baicalin on Bcap-37 cell apoptosis. Real-time quantitative polymerase chain reaction (RT-PCR) was conducted to observe the influence of baicalin on mRNA expressions of apoptosis-related genes. Western blot was executed to further explore the action of baicalin on apoptosis-related proteins. PD98059 (a specific inhibitor of ERK) and SB203580 (a specific inhibitor of p38 MAPK) were used to further clarify the intrinsic mechanism of baicalin regulating apoptosis in Bcap-37 cells. Results Compared with the control group, baicalin significantly inhibits the proliferation activity of Bcap-37 cells in a concentration- and time-dependent manner, with a p-value < 0.05. The transwell assay indicated that the migration viability of cells decreased further, followed by the increased concentration of baicalin, and the p-value had a statistical difference. Besides, flow cytometry was conducted to assess the effects of baicalin on the early and late apoptosis rates of Bcap-37 cells, and results showed that baicalin highly promoted the apoptosis level both at the early and late stages with a statistical difference in a concentration-dependent manner ( p < 0.05). Results of RT-PCR presented that, compared with the control group, baicalin significantly activated the mRNA expression of Bax, p38, and p-ERK1 and abolished the mRNA expression of Bcl-2 in every dosing group in a concentration-dependent way ( p < 0.05). Western blot exhibited that, compared with the control group, baicalin promoted the protein expression of caspase-3, caspase-9, Bax, p38, P-ERK, and p53 while playing an opposite function to Bcl-2 in each dosing group ( p values have statistical differences). At last, PD98059 and SB203580 were applied to explore the potential mechanism of baicalin in apoptosis promotion. And results revealed that, compared with the group treated with baicalin alone, protein expression of Bax, p38, p-ERK, caspase-3, and caspase-9 was downregulated obviously in the group treated with both baicalin and PD98059 or SB203580 ( p < 0.05). The p53 expression inhibition showed a difference only when compared to the group adding PD98059. Compared with the blank group, a statistical difference was only observed in Bcl-2 expression in the group treated with baicalin in combination with PD98059 or SB203580 ( p < 0.05). Interestingly, a p53 expression difference was only displayed between the blank group and the group treated with baicalin and SB203580 ( p < 0.05). Conclusion Our study observed that baicalin inhibits the proliferation and migration ability of Bcap-37 cells. In addition, baicalin induces cell apoptosis via the ERK/p38 MAPK signal pathway.

Scutellarin alleviates tensile stress-induced proliferation and migration of venous smooth muscle cells via mediating the p38 MAPK pathway

ObjectiveAbnormal proliferation and migration of biomechanical force-induced venous smooth muscle cells (VSMCs) is a major cause to limit the efficacy of coronary artery bypass grafting (CABG) for coronary heart disease (CHD). Scutellarin is the main active ingredient of Erigeron Breviscapus, and has broad-spectrum pharmacological effects. Therefore, the present study was proposed to investigate the effect of Scutellarin on VSMCs under tensile stress. MethodsAfter interfering with VSMCs at different tensile stresses, the optimal tensile stress was screened. In a tensile stress environment, 100 μM Scutellarin and Hesperetin (p38 MAPK pathway activator) was used to treatment with VSMCs. CCK-8, EDU, Wound healing, flow cytometry and western blotting assays were used to detect cell proliferation, migration, apoptosis, and the expression of apoptosis-related proteins (Caspase3, Bcl2 and Bax). ResultsTensile stress with 10% significantly enhanced the activity, wound-healing ratio, and EDU+ cells of VSMCs, and decreased their apoptosis ratio. Moreover, it upregulated Bcl2 expression, and downregulated cleaved-Caspase3 and Bax expression of VSMCs. Hence, 10% tensile stress was selected to creates a tensile stress environment for VSMCs. Interestingly, 100 μM Scutellarin alleviated the effect of 10% tensile stress on the phenotype of VSMCs. Notably, 10% tensile stress increased the phosphorylation level of p38 MAPK (Thr180 +Tyr182) in VSMCs, which was restricted by Scutellarin. Further, Hesperetin restored the effect of Scutellarin on the phenotype of VSMCs. ConclusionScutellarin alleviates tension stress-induced proliferation and migration of VSMCs via suppressing p38 MAPK pathway. Scutellarin may be used as an adjunctive strategy for future GABG treatment in CHD patients.

Roles of MAPK and Nrf2 signaling pathways in quercetin alleviating redox imbalance induced by hydrogen peroxide in mammary epithelial cells

Abstract Oxidative stress is a risk factor for mammary health, resulting in decreased milk yield and milk quality. Application of exogenous bioactive compounds has been a research focus of antioxidation of animals in the mammary gland. Quercetin is a flavonoid extracted from vegetables, fruits and tea and has been shown to have a variety of biological activities, but the effect of quercetin on redox imbalance in mammary epithelial cells is unclear. In this study, cells of HC11, a mouse mammary epithelial cell line, were treated with quercetin, and the effects and molecular mechanisms of quercetin protection on hydrogen peroxide-induced oxidative stress were studied. Results showed that 20 μΜ quercetin attenuated hydrogen peroxide-induced lactate dehydrogenase release and reactive oxygen species (ROS) accumulation and alleviated the reduction of cell viability and antioxidant capacity. Quercetin significantly restored the activation of mitogen-activated protein kinase (MAPK) and nuclear factor E2-related factor 2 (Nrf2) pathways induced by hydrogen peroxide. Importantly, the inhibitors of p38 MAPK and extracellular regulated protein pathways affected the activation of Nrf2 pathway. All inhibitors of MAPK and Nrf2 pathways reduced the protective effects of quercetin on cell proliferation, the activity of catalase and the expression of glutamate-cysteine ligase modifier subunit. Meanwhile, the effects of quercetin on the production of ROS and expression of glutamate/cystine reverse transporter light chain were mainly dependent on Nrf2 pathway. In summary, the protective effect of quercetin in mammary epithelial cells was mediated via MAPK and Nrf2 pathways.

Electroacupuncture at the Dazhui and Baihui acupoints and different frequencies (10 and 50 Hz) protects against apoptosis by up-regulating ERK1/2-mediated signaling in rats after global cerebral ischemia.

This study assessed the effects of electroacupuncture (EA) stimulation at different frequencies at the Dazhui and Baihui acupoints in the subacute phase after transient global cerebral ischemia (GCI). Rats were subjected to GCI for 25 min, followed by reperfusion for 7 days. EA at acupoints was performed at 10, 30, or 50 Hz, 1 day after reperfusion and then once daily for 6 consecutive days. EA at acupoints at 10 and 50 Hz effectively down-regulated apoptosis in the hippocampal cornu ammonis 1(CA1) area and ameliorated memory deficits. Moreover, EA treatment at 10 and 50 Hz markedly increased phospho (p)-extracellular signal-regulated protein kinase 1/2 (ERK1/2), p-ERK1/2/neuronal nuclei (NeuN), p-cAMP response element-binding protein (CREB)/p-ERK1/2, B-cell lymphoma-2 (Bcl-2)/p-CREB, and X-linked inhibitor of apoptosis protein/NeuN expression levels and decreased Bcl-2 homologous antagonist/killer, second mitochondria-derived activator of caspase/direct inhibitor of apoptosis-binding protein with low pI, cytochrome c, cleaved caspase-3, and apoptosis-inducing factor expression levels. Furthermore, 10-Hz EA treatment effectively increased p-p38 mitogen-activated protein kinase (MAPK), p-p38 MAPK/NeuN, and p-CREB/p-p38 MAPK expression levels. Pretreatment with U0126 (ERK1/2 inhibitor) completely abrogated the effects of 10- and 50-Hz EA treatments on the aforementioned protein expression levels. Similarly, pretreatment with SB203580 (p38 MAPK inhibitor) completely abrogated the effects of 10-Hz treatment on the aforementioned protein expression levels. The effects of 10- and 50-Hz EA treatments on mitochondria-related apoptosis can be attributed to the activation of ERK1/2/p38 MAPK/CREB/Bcl-2- and ERK1/2/CREB/Bcl-2-mediated signaling, respectively, in the hippocampal CA1 area at 7 days after transient GCI.

Circulating IL-17F, but not IL-17A, is elevated in severe COVID-19 and leads to an ERK1/2 and p38 MAPK-dependent increase in ICAM-1 cell surface expression and neutrophil adhesion on endothelial cells.

Severe COVID-19 is associated with neutrophilic inflammation and immunothrombosis. Several members of the IL-17 cytokine family have been associated with neutrophilic inflammation and activation of the endothelium. Therefore, we investigated whether these cytokines were associated with COVID-19. We investigated the association between COVID-19 and circulating plasma levels of IL-17 cytokine family members in participants to the Biobanque québécoise de la COVID-19 (BQC19), a prospective observational cohort and an independent cohort from Western University (London, Ontario). We measured the in vitro impact of IL-17F on intercellular adhesion molecule 1 (ICAM-1) cell surface expression and neutrophil adhesion on endothelial cells in culture. The contribution of two Mitogen Activated Protein Kinase (MAPK) pathways was determined using small molecule inhibitors PD184352 (a MKK1/MKK2 inhibitor) and BIRB0796 (a p38 MAPK inhibitor). We found increased IL-17D and IL-17F plasma levels when comparing SARS-CoV-2-positive vs negative hospitalized participants. Moreover, increased plasma levels of IL-17D, IL-17E and IL-17F were noted when comparing severe versus mild COVID-19. IL-17F, but not IL-17A, was significantly elevated in people with COVID-19 compared to healthy controls and with more severe disease. In vitro work on endothelial cells treated with IL-17F for 24h showed an increase cell surface expression of ICAM-1 accompanied by neutrophil adhesion. The introduction of two MAPK inhibitors significantly reduced the binding of neutrophils while also reducing ICAM-1 expression at the surface level of endothelial cells, but not its intracellular expression. Overall, these results have identified an association between two cytokines of the IL-17 family (IL-17D and IL-17F) with COVID-19 and disease severity. Considering that IL-17F stimulation promotes neutrophil adhesion to the endothelium in a MAPK-dependent manner, it is attractive to speculate that this pathway may contribute to pathogenic immunothrombosis in concert with other molecular effectors.

Hyperbaric Lidocaine Aggravates Diabetic Neuropathic Pain by Targeting p38 MAPK/ERK and PINK1/Parkin-Mediated Mitophagy Signaling Pathway.

Diabetic neuropathic pain (DNP) is a complication of diabetes mellitus (DM). Hyperbaric lidocaine (HL), a local anesthetics drug, has neurotoxicity. The present study aims to study the effect and molecular mechanisms of HL on spinal nerve injury in DNP. The DNP rat model was established through a high-fat-glucose diet in combination with Streptozotocin (STZ) administration. SB203580 and PD98059 were utilized to inhibit p38 mitogen-activated protein kinase (p38 MAPK) and extracellular signal-regulated kinase (ERK). The mechanical paw withdrawal threshold (PWT) and the thermal paw withdrawal latency (PWL) were tested to evaluate rats' mechanical allodynia and thermal hyperalgesia. Hematoxylin-eosin (H&E) and terminal deoxynucleotidyltransferase-mediated dUTP nick-end Labeling (TUNEL) staining were performed to evaluate the pathological changes and neuron apoptosis in spinal cord tissues of L4-5. Western blotting analysis and reverse transcription-polymerase chain reaction (RT-qPCR) assay were used to measure the levels of proteins and mRNAs, respectively. PWT and PWL were decreased in DNP rats with serious spinal nerve injury. HL administration downregulated the PWT and PWL and aggravated spinal nerve injury in DNP rats, but isobaric lidocaine had no effects on these changes. Meanwhile, p38 MAPK/ERK signaling and PTEN-induced kinase 1 (PINK1)-mediated mitophagy were activated in DNP, which was enhanced by HL but not isobaric lidocaine. Blocking p38 MAPK/ERK signaling could effectively attenuate HL-induced spinal nerve injury and inhibit mitophagy. In summary, HL can aggravate spinal cord tissue damage in DNP rats by inducing PINK1-mediated mitophagy via activating p38 MAPK/ERK signaling. Our data provide a novel insight that supports the potential role of p38 MAPK/ERK signaling in acting as a therapeutic target for HL-induced neurotoxicity.

Atractylenolide II combined with Interferon-γ synergistically ameliorates colorectal cancer progression in vivo and in vitro by blocking the NF-kB p65/PD-L1 pathway.

Purpose: Atractylodes macrocephala Koidz is a widely used classical traditional Chinese herbal medicine, that has shown remarkable efficacy in cancers. Colorectal cancer (CRC) is the most common malignant tumor globally. Interferon (IFN)-γ, a prominent cytokine involved in anti-tumor immunity that has cytostatic, pro-apoptotic, and immune-stimulatory properties for the detection and removal of transformed cells. Atractylenolides-II (AT-II) belongs to the lactone compound that is derived from Atractylodes macrocephala Koidz with anti-cancer activity. However, whether AT-II combined with IFN-γ modulates CRC progression and the underlying mechanisms remain unclear. The present study aimed to elucidate the efficacy and pharmaceutical mechanism of action of AT-II combined with IFN-γ synergistically against CRC by regulating the NF-kB p65/PD-L1 signaling pathway. Methods: HT29 and HCT15 cells were treated with AT-II and IFN-γ alone or in combination and cell viability, migration, and invasion were then analyzed using Cell Counting Kit-8 (CCK-8) and Transwell assays, respectively. Furthermore, the underlying mechanism was investigated through western blot assay. The role of AT-II combined with IFN-γ on tumor growth and lung metastases was estimated in vivo. Finally, the population of lymphocytes in tumor tissues of lung metastatic C57BL/6 mice and the plasma cytokine levels were confirmed by flow cytometry and enzyme-linked immunosorbent assay (ELISA). Results: AT-II or the combination IFN-γ significantly inhibited the growth and migration abilities of CRC cells in vitro and in vivo. The biological mechanisms behind the beneficial effects of AT-II combined with IFN-γ were also measured and inhibition of p38 MAPK, FAK, Wnt/β-catenin, Smad, and NF-kB p65/PD-L1 pathways was observed. Moreover, AT-II combined with IFN-γ significantly inhibited HCT15 xenograft tumor growth and lung metastases in C57BL/6 mice, which was accompanied by lymphocyte infiltration into the tumor tissues and inflammatory response inactivation. Conclusions: The results showed that the AT-II in combination with IFN-γ could be used as a potential strategy for tumor immunotherapy in CRC. More importantly, the mechanism by which AT-II suppressed CRC progressions was by inhibiting the NF-kB p65/PD-L1 signal pathway.

Identification of triciribine as a novel myeloid cell differentiation inducer.

Differentiation therapy using all-trans retinoic acid (ATRA) for acute promyelocytic leukemia (APL) is well established. However, because the narrow application and tolerance development of ATRA need to be improved, we searched for another efficient myeloid differentiation inducer. Kinase activation is involved in leukemia biology and differentiation block. To identify novel myeloid differentiation inducers, we used a Kinase Inhibitor Screening Library. Using a nitroblue tetrazolium dye reduction assay and real-time quantitative PCR using NB4 APL cells, we revealed that, PD169316, SB203580, SB202190 (p38 MAPK inhibitor), and triciribine (TCN) (Akt inhibitor) potently increased the expression of CD11b. We focused on TCN because it was reported to be well tolerated by patients with advanced hematological malignancies. Nuclear/cytoplasmic (N/C) ratio was significantly decreased, and myelomonocytic markers (CD11b and CD11c) were potently induced by TCN in both NB4 and acute myeloid leukemia (AML) M2 derived HL-60 cells. Western blot analysis using NB4 cells demonstrated that TCN promoted ERK1/2 phosphorylation, whereas p38 MAPK phosphorylation was not affected, suggesting that activation of the ERK pathway is involved in TCN-induced differentiation. We further examined that whether ATRA may affect phosphorylation of ERK and p38, and found that there was no obvious effect, suggesting that ATRA induced differentiation is different from TCN effect. To reveal the molecular mechanisms involved in TCN-induced differentiation, we performed microarray analysis. Pathway analysis using DAVID software indicated that "hematopoietic cell lineage" and "cytokine-cytokine receptor interaction" pathways were enriched with high significance. Real-time PCR analysis demonstrated that components of these pathways including IL1β, CD3D, IL5RA, ITGA6, CD44, ITGA2B, CD37, CD9, CSF2RA, and IL3RA, were upregulated by TCN-induced differentiation. Collectively, we identified TCN as a novel myeloid cell differentiation inducer, and trials of TCN for APL and non-APL leukemia are worthy of exploration in the future.

Использование блокаторов р38 МАРK в лечении экспериментального перитонита

Использование блокаторов р38 МАРK в лечении экспериментального перитонита

Dietary sodium butyrate and forskolin promote cell proliferation to resist Citrobacter rodentium infection by lysozyme upregulation

The invasion of pathogens derived from diet or the environment triggers intestinal inflammation, which is a result of the host intestinal barrier damage and immune dysfunction, such as the decrease of host defense peptides (HDPs) and inhibition of cell proliferation. Herein, the siRNA interference demonstrated that a critical lysozyme, which was mainly induced by dietary supplementations of sodium butyrate and forskolin, improved cell proliferation by inhibiting p38 MAPK and JNK signaling pathways and reinforced the intestinal barrier. Moreover, we established a mouse model of intestinal inflammation with Citrobacter rodentium (C. rodentium). It was found that NaBu and FSK stimulated intestinal epithelial proliferation to repair barrier damage, and performed stronger disease resistance to C. rodentium infection on account of the lysozyme upregulation in colon. Therefore, this study revealed that NaBu and FSK prevented or alleviated the development of foodborne infections by promoting lysozyme expression, which may be mediated by the effect of lysozyme on promoting cell proliferation and improving barrier function.

Antitumor effects of a novel photosensitizer-mediated photodynamic therapy and its influence on the cell transcriptome.

Photodynamic therapy (PDT) is a promising cancer treatment. This study investigated the antitumor effects and mechanisms of a novel photosensitizer meso-5-[ρ-diethylene triamine pentaacetic acid-aminophenyl]-10,15,20-triphenyl-porphyrin (DTP) mediated PDT (DTP-PDT). Cell viability, reactive oxygen species (ROS), and apoptosis were measured with a Cell Counting Kit-8 assay, DCFH-DA fluorescent probe, and Hoechst staining, respectively. Cell apoptosis- and autophagy-related proteins were examined using western blotting. RNA sequencing was used to screen differentially expressed mRNAs (DERs), and bioinformatic analysis was performed to identify the major biological events after DTP-PDT. Our results show that DTP-PDT inhibited cell growth and induced ROS generation in MCF-7 and SGC7901 cells. The ROS scavenger N-acetyl-L-cysteine (NAC) and the P38 MAPK inhibitor SB203580 alleviated DTP-PDT-induced cytotoxicity. DTP-PDT induced cell apoptosis together with upregulated Bax and downregulated Bcl-2, which could also be inhibited by NAC or SB203580. The level of LC3B-II, a marker of autophagy, was increased by DTP-PDT. A total of 3496 DERs were obtained after DTP-PDT. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses indicated that DERs included those involved in cytosolic ribosomes, the nuclear lumen, protein binding, cell cycle, protein targeting to the endoplasmic reticulum, and ribosomal DNA replication. Disease Ontology and Reactome enrichment analyses indicated that DERs were associated with a variety of cancers and cell cycle checkpoints. Protein-protein interaction results demonstrated that cdk1 and rps27a ranked in the top 10 interacting genes. Therefore, DTP-PDT could inhibit cell growth and induce cell apoptosis and autophagy, partly through ROS and the P38 MAPK signaling pathway. Genes associated with the cell cycle, ribosomes, DNA replication, and protein binding may be the key changes in DTP-PDT-mediated cytotoxicity.

Contribution of HSP90 Cleavage to the Cytotoxic Effect of Suberoylanilide Hydroxamic Acid In Vivo and the Involvement of TXNIP in HSP90 Cleavage.

Heat shock protein (HSP) 90 is expressed in most living organisms, and several client proteins of HSP90 are necessary for cancer cell survival and growth. Previously, we found that HSP90 was cleaved by histone deacetylase (HDAC) inhibitors and proteasome inhibitors, and the cleavage of HSP90 contributes to their cytotoxicity in K562 leukemia cells. In this study, we first established mouse xenograft models with K562 cells expressing the wild-type or cleavage-resistant mutant HSP90β and found that the suppression of tumor growth by the HDAC inhibitor suberoylanilide hydroxamic acid (SAHA) was interrupted by the mutation inhibiting the HSP90 cleavage in vivo. Next, we investigated the possible function of thioredoxin interacting protein (TXNIP) in the HSP90 cleavage induced by SAHA. TXNIP is a negative regulator for thioredoxin, an antioxidant protein. SAHA transcriptionally induced the expression of TXNIP in K562 cells. HSP90 cleavage was induced by SAHA also in the thymocytes of normal mice and suppressed by an anti-oxidant and pan-caspase inhibitor. When the thymocytes from the TXNIP knockout mice and their wild-type littermate control mice were treated with SAHA, the HSP90 cleavage was detected in the thymocytes of the littermate controls but suppressed in those of the TXNIP knockout mice suggesting the requirement of TXNIP for HSP90 cleavage. We additionally found that HSP90 cleavage was induced by actinomycin D, β-mercaptoethanol, and p38 MAPK inhibitor PD169316 suggesting its prevalence. Taken together, we suggest that HSP90 cleavage occurs also in vivo and contributes to the anti-cancer activity of various drugs in a TXNIP-dependent manner.

The protective effect of Ergolide in osteoarthritis: In vitro and in vivo studies

Osteoarthritis (OA), a prevalent degenerative condition, occurs due to the deterioration of joint tissues and cells. Consequently, safeguarding chondrocytes against damage caused by inflammation is an area of future research emphasis. There is growing evidence that Ergolide (ERG) has multiple biological functions. Nevertheless, it is still uncertain whether it can hinder the advancement of OA. In this study, we investigate the ERG's potential to reduce inflammation and protect cartilage. ERG treatment in vitro effectively inhibited the excessive production of pro-inflammatory substances, such as inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX2), and tumor necrosis factor-α (TNF-α), leading to their complete suppression. Furthermore, ERG suppressed the production of matrix-degrading enzymes (ADAMTS-5) and matrix metalloproteinase 13 (MMP13), consequently impeding the breakdown of extracellular matrix (ECM) and restraining the synthesis of collagenase II and Aggrecan. Through the P38/MAPK pathway, we discovered that ERG hinders the activation of NF-κB in chondrocytes induced by IL-1β. The protective effect of ERG was enhanced by the p38 MAPK inhibitor SB203580. In vivo, ERG further demonstrated protective effects on cartilage in animal models of DMM. In conclusion, the study has discovered that ERG exhibits innovative therapeutic potential in the context of OA.

1,3-Dichloroadamantyl-Containing Ureas as Potential Triple Inhibitors of Soluble Epoxide Hydrolase, p38 MAPK and c-Raf.

Soluble epoxide hydrolase (sEH) is an enzyme involved in the metabolism of bioactive lipid signaling molecules. sEH converts epoxyeicosatrienoic acids (EET) to virtually inactive dihydroxyeicosatrienoic acids (DHET). The first acids are "medicinal" molecules, the second increase the inflammatory infiltration of cells. Mitogen-activated protein kinases (p38 MAPKs) are key protein kinases involved in the production of inflammatory mediators, including tumor necrosis factor-α (TNF-α) and cyclooxygenase-2 (COX-2). p38 MAPK signaling plays an important role in the regulation of cellular processes, especially inflammation. The proto-oncogenic serine/threonine protein kinase Raf (c-Raf) is a major component of the mitogen-activated protein kinase (MAPK) pathway: ERK1/2 signaling. Normal cellular Raf genes can also mutate and become oncogenes, overloading the activity of MEK1/2 and ERK1/2. The development of multitarget inhibitors is a promising strategy for the treatment of socially dangerous diseases. We synthesized 1,3-disubstituted ureas and diureas containing a dichloroadamantyl moiety. The results of computational methods show that soluble epoxide hydrolase inhibitors can act on two more targets in different signaling pathways of mitogen-activated protein kinases p38 MAPK and c-Raf. The two chlorine atoms in the adamantyl moiety may provide additional Cl-π interactions in the active site of human sEH. Molecular dynamics studies have shown that the stability of ligand-protein complexes largely depends on the "spacer effect." The compound containing a bridge between the chloroadamantyl fragment and the ureide group forms more stable ligand-protein complexes with sEH and p38 MAPK, which indicates a better conformational ability of the molecule in the active sites of these targets. In turn, a compound containing two chlorine atoms forms a more stable complex with c-Raf, probably due to the presence of additional halogen bonds of chlorine atoms with amino acid residues.

Effect of ST36 electroacupuncture on the switch of skeletal muscle fibres in mice with sciatic nerve dissociation.

Skeletal muscle is striated muscle that moves autonomously and is innervated by peripheral nerves. Peripheral nerve injury is very common in clinical treatment. However, the commonly used treatment methods often focus on the regeneration of the injured nerve but overlook the pathological changes in the injured skeletal muscle. Acupuncture, as the main treatment for denervated skeletal muscle atrophy, is used extensively in clinical practice. In the present study, a mouse model of lower limb sciatic nerve detachment was constructed and treated with electroacupuncture Stomach 36 to observe the atrophy of lower limb skeletal muscle and changes in skeletal muscle fibre types before and after electroacupuncture Stomach 36 treatment. Mice with skeletal muscle denervation showed a decrease in the proportion of IIa muscle fibres and an increase in the proportion of IIb muscle fibres, after electroacupuncture Stomach 36. The changes were reversed by specific activators of p38 MAPK, which increased IIa myofibre ratio. The results suggest that electroacupuncture Stomach 36 can reverse the change of muscle fibre type from IIb to IIa after denervation of skeletal muscle by inhibiting p38 MAPK. The results provide an important theoretical basis for the treatment of clinical peripheral nerve injury diseases with electroacupuncture, in addition to novel insights that could facilitate the study of pathological changes of denervated skeletal muscle.

P38 MAPK inhibitor SB202190 suppresses ferroptosis in the glutamate-induced retinal excitotoxicity glaucoma model.

JOURNAL/nrgr/04.03/01300535-202410000-00031/figure1/v/2024-02-06T055622Z/r/image-tiff Glutamate excitotoxicity has been shown to play an important role in glaucoma, and glutamate can induce ferroptosis. The p38 mitogen-activated protein kinase (MAPK) pathway inhibitor SB202190 has a potential ability to suppress ferroptosis, and its downstream targets, such as p53, have been shown to be associated with ferroptosis. However, whether ferroptosis also occurs in retinal ganglion cells in response to glutamate excitotoxicity and whether inhibition of ferroptosis reduces the loss of retinal ganglion cells induced by glutamate excitotoxicity remain unclear. This study investigated ferroptosis in a glutamate-induced glaucoma rat model and explored the effects and molecular mechanisms of SB202190 on retinal ganglion cells. A glutamate-induced excitotoxicity model in R28 cells and an N-methyl-D-aspartate-induced glaucoma model in rats were used. In vitro experiments showed that glutamate induced the accumulation of iron and lipid peroxide and morphological changes of mitochondria in R28 cells, and SB202190 inhibited these changes. Glutamate induced the levels of p-p38 MAPK/p38 MAPK and SAT1 and decreased the expression levels of ferritin light chain, SLC7A11, and GPX4. SB202190 inhibited the expression of iron death-related proteins induced by glutamate. In vivo experiments showed that SB202190 attenuated N-methyl-D-aspartate-induced damage to rat retinal ganglion cells and improved visual function. These results suggest that SB202190 can inhibit ferroptosis and protect retinal ganglion cells by regulating ferritin light chain, SAT1, and SLC7A11/Gpx4 pathways and may represent a potential retina protectant.