OBJECTIVE: To screen differentially expressed long non-coding RNAs (lncRNAs) in the liver of mice infected with Schistosoma japonicum during the chronic pathogenic stage and identify their functions, so as to provide insights into unravelling the role of lncRNAs in S. japonicum infection-induced liver disorders.
METHODS: Twenty 6-week-old C57BL/6 mice were randomly divided into two groups, of 10 animals each group. Each mouse in the experimental group was infected with (15 ± 2) S. japonicum cercariae via the abdomen for modeling chronic S. japonicum infection in mice, and distilled water served as controls. All mice were sacrificed 70 days post-infection, and mouse liver specimens were sampled for RNA extraction and library construction. All libraries were sequenced on the Illumina NovaSeq 6000 sequencing platform. Data cleaning was performed using the fastp software, and reference genome alignment and gene expression (FPKM) calculation were performed using the HISAT2 software. Potential lncRNA sequences were predicted using the software CNIC, CPC, Pfam, and PLEK, and potential lncRNAs were screened. Differentially expressed lncRNAs were screened with the DESeq2 software and subjected to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses to identify biological processes and metabolic pathways involved in target genes of differentially expressed lncRNAs.
RESULTS: A total of 333 potential lncRNAs were screened, and 67 were identified as differentially expressed lncRNAs, including 49 up-regulated and 18 down-regulated lncRNAs. A total of 53 target genes were predicted for differentially expressed lncRNAs. GO enrichment analysis showed that these target genes were mainly enriched in biological process and molecular function, among which Sema7a, Arrb1, and Ccl21b genes may be hub target genes for positive regulation of extracellular regulated protein kinase 1 (ERK1) and ERK2 cascades and may participate in the regulation of collagen expression. KEGG enrichment analysis showed that the target genes of differentially expressed lncRNAs were mainly enriched in cytokine-cytokine receptor interaction, viral protein interactions with cytokines and cytokine receptors, chemokine signaling pathway, and nuclear factor kappa-B (NF-κB) signaling pathway.
CONCLUSIONS: This study identifies differentially expressed lncRNAs and functional enrichment of their target genes in the liver of mice during the chronic pathogenic stage of S. japonicum infection. Up-regulated lncRNAs may affect biological processes of ERK1/2 cascades and chemokine signaling pathways via target genes Sema7a, Arrb1, and Ccl21b, thereby affecting collagen expression and inflammatory signal pathways, ultimately affecting the development of liver disorders.
［摘要］ 目的 筛选日本血吸虫感染小鼠慢性致病阶段肝脏中差异表达长非编码 RNA (long non-coding RNA, lncRNA) 并进行功能分析, 为探索 lncRNA 在日本血吸虫感染所致肝脏病变中的作用提供参考。方法 20 只 6 周龄 C57BL/6 小鼠 随机分为 2 组, 每组 10 只。实验组每只小鼠采用腹部贴片法感染 (15 ± 2) 条日本血吸虫尾蚴建立日本血吸虫慢性感染小 鼠模型, 以蒸馏水作为对照组。两组小鼠均于感染 70 d 后剖杀, 获取小鼠肝脏组织样本, 进行RNA抽提及文库构建。通 过 Illumina NovaSeq 6000 测序平台对文库进行测序, 采用 fastp 软件进行数据清洗, 使用 HISAT2 软件进行参考基因组比 对及基因表达量 (FPKM) 计算。采用 CNIC、CPC、Pfam、PLEK 软件对潜在lncRNA序列进行编码潜能预测, 筛选出潜在 lncRNA。采用 DESeq2 软件进行基因差异表达分析, 筛选出差异表达 lncRNA。通过基因本体论 (Gene Ontology, GO) 和京 都基因和基因组百科全书 (Kyoto Encyclopedia of Genes and Genomes, KEGG) 富集分析, 挖掘差异表达 lncRNA 靶基因参 与的生物学过程和代谢途径。结果 共筛选出 333 个潜在 lncRNA, 67 个鉴定为差异表达 lncRNA, 其中 49 个表达上调、18 个表达下调。差异表达 lncRNA 预测靶基因共 53 个, GO 富集分析显示这些靶基因主要富集在生物学过程和分子功 能; 其中 Sema7a、Arrb1、Ccl21b 等基因可能是细胞外调节蛋白激酶 1 (extracellular regulated protein kinase, ERK1) 和 ERK2 级联正调控生物学过程的关键靶基因, 可能参与调控胶原蛋白表达。KEGG 富集分析显示, 差异表达 lncRNA 靶基因主 要参与细胞因子-细胞因子受体相互作用、病毒蛋白与细胞因子和细胞因子受体的相互作用、趋化因子信号通路和核因 子κB (nuclear factor kappa-B, NF-κB) 通路等信号通路。结论 本研究鉴定了日本血吸虫感染小鼠慢性致病阶段肝脏中 差异表达 lncRNA 及其靶基因的功能富集, 其中上调表达的 lncRNA 可能通过调控 Sema7a、Arrb1、Ccl21b 等靶基因影响 ERK1/2 级联等生物学过程以及趋化因子信号通路等, 影响胶原蛋白表达及炎症相关信号通路, 从而影响肝脏病变发展。.

β-Amyloid peptide (Aβ) deposition in the brain is an important pathological change in Alzheimer\'s disease (AD). Insulin-degrading enzyme (IDE), which is regulated transcriptionally by peroxisome proliferator-activated receptor γ (PPARγ), is able to proteolyze Aβ. One of the members of the MAPK family, ERK, is able to mediate the phosphorylation of PPARγ at Ser112, thereby inhibiting its transcriptional activity. Ginsenoside Rg1 is one of the active ingredients in the natural medicine ginseng and has inhibitory effects on Aβ production. The present study was designed to investigate whether ginsenoside Rg1 is able to affect the regulation of PPARγ based on the expression of its target gene, IDE, and whether it is able to promote Aβ degradation via inhibition of the ERK/PPARγ phosphorylation pathway. In the present study, primary cultured rat hippocampal neurons were treated with Aβ1-42, ginsenoside Rg1 and the ERK inhibitor PD98059, and subsequently TUNEL staining was used to detect the level of neuronal apoptosis. ELISA was subsequently employed to detect the intra- and extracellular Aβ1-42 levels, immunofluorescence staining and western blotting were used to detect the translocation of ERK from the cytoplasm to the nucleus, immunofluorescence double staining was used to detect the co-expression of ERK and PPARγ, and finally, western blotting was used to detect the phosphorylation of PPARγ at Ser112 and IDE expression. The results demonstrated that ginsenoside Rg1 or PD98059 were able to inhibit primary cultured hippocampal neuron apoptosis induced by Aβ1-42 treatment, reduce the levels of intra- and extraneuronal Aβ1-42 and inhibit the translocation of ERK from the cytoplasm to the nucleus. Furthermore, administration of ginsenoside Rg1 or PD98059 resulted in attenuated co-expression of ERK and PPARγ, inhibition of phosphorylation of PPARγ at Ser112 mediated by ERK and an increase in IDE expression. In addition, the effects when PD98059 to inhibit ERK followed by treatment with ginsenoside Rg1 were found to be more pronounced than those when using PD98059 alone. In conclusion, ginsenoside Rg1 was demonstrated to exert neuroprotective effects on AD via inhibition of the ERK/PPARγ phosphorylation pathway, which led to an increase in IDE expression, the promotion of Aβ degradation and the decrease of neuronal apoptosis. These results could provide a theoretical basis for the clinical application of ginsenoside Rg1 in AD.

Objective: To study the effects of estradiol (E2) on alleviating myocardial ischemia/reperfusion(I/R) injury through estrogen receptorβ(ERβ) mediated extracellular regulated protein kinases(ERK) pathway activation. Methods: Eighty-four adult female SD rats were ovariectomized and randomly divided into control group, NC siRNA adeno-associated virus (AAV) group received sham operation, the myocardial I/R injury model was prepared by ligation of the left anterior descending coronary artery in I/R group, E2+I/R group, NC siRNA AAV+I/R group, NC siRNA AAV+E2+I/R group and ERβ-siRNA AAV+E2+I/R group. E2+I/R group, NC siRNA AAV+E2+I/R group and ERβ-siRNA AAV+E2+I/R group were treated with E2 0.8 mg/kg by gavage for 60 days before modeling. NC siRNA AAV+I/R group, NC siRNA AAV+E2+I/R group, and ERβ-siRNA AAV+E2+I/R group were treated with AAV by caudal vein injection 24 h before modeling. After 120 min of reperfusion, the contents of serum lactate dehydrogenase (LDH), phosphocreatine kinase (CK), phosphocreatine kinase isoenzyme (CK-MB), myocardial infarction area and the expressions of ERβ, p-ERK, the contents of tumor necrosis factor-α(TNF-α), interleukin-1β(IL-1 β), malondialdehyde (MDA) and total antioxidant capacity (T-AOC) in myocardium were measured. Results: The contents of serum LDH, CK, CK-MB, myocardial infarction area and the contents of TNF-α, IL-1 β, MDA in myocardium of I/R group were higher than those of the control group, the expression levels of ERβ and p-ERK and the content of T-AOC were lower than those in the control group (P＜0.05). The contents of serum LDH, CK and CK-MB, myocardial infarction area and the contents of TNF-α, IL-1 β and MDA in myocardium of E2+I/R group were lower than those of the I/R group, the expression levels of ERβ and p-ERK and the content of T-AOC were higher than those of the I/R group(P＜0.05). After knockdown ERβ by caudal vein injection of ERβ-siRNA AAV, the contents of serum LDH, CK and CK-MB, myocardial infarction area and the contents of TNF-α, IL-1 β and MDA in myocardium of ERβ-siRNA AAV+E2+I/R group were higher than those of NC-siRNA AAV+E2+I/R, the expression levels of ERβ and p-ERK and the content of T-AOC were lower than those of NC-siRNA AAV+E2+I/R(P＜0.05). Conclusion: E2 has protective effects on myocardial I / R injury in ovariectomized rats, which are related to the promotion of ERβ mediating the activation of ERK pathway, reducing inflammatory and oxidative stress responses.
目的: 研究雌二醇(E2)通过雌激素受体β(ERβ)介导细胞外调节蛋白激酶(ERK)通路激活减轻心肌缺血/再灌注(I/R)损伤的作用及机制。方法: 84只成年雌性SD大鼠进行去卵巢手术并随机分为:对照组、NC-siRNA腺相关病毒(AAV)组进行假手术,I/R组、E2+I/R组、NC-siRNA AAV+I/R组、NC-siRNA AAV+E2+I/R组、ERβ-siRNA AAV+E2+I/R组。采用冠状动脉左前降支结扎的方法制备心肌I/R损伤模型,E2+I/R组、NC-siRNA AAV+E2+I/R组、ERβ-siRNA AAV+E2+I/R组造模前给予E2灌胃、连续60 d,NC-siRNA AAV+I/R组、NC-siRNA AAV+E2+I/R组、ERβ-siRNA AAV+E2+I/R组造模前24 h给予相应AAV尾静脉注射。再灌注120 min后,检测血清乳酸脱氢酶(LDH)、磷酸肌酸激酶(CK)、磷酸肌酸激酶同工酶(CK-MB)含量,心肌梗死面积,心肌中ERβ、p-ERK表达水平及肿瘤坏死因子-α(TNF-α)、白介素-1β(IL-1β)、丙二醛(MDA)、总抗氧化力(T-AOC)的含量。结果: I/R组的血清LDH、CK、CK-MB含量、心肌梗死面积及心肌中TNF-α、IL-1β、MDA的含量均高于对照组,心肌中ERβ、p-ERK的表达水平及T-AOC的含量均低于对照组(P＜0.05);E2+I/R组的血清LDH、CK、CK-MB含量、心肌梗死面积及心肌中TNF-α、IL-1β、MDA的含量均低于I/R组,心肌中ERβ、p-ERK的表达水平及T-AOC的含量均高于I/R组(P＜0.05);尾静脉注射ERβ-siRNA AAV敲低ERβ的表达后,ERβ-siRNA AAV+E2+I/R组的血清LDH、CK、CK-MB含量、心肌梗死面积及心肌中TNF-α、IL-1β、MDA的含量均高于NC-siRNA AAV+E2+I/R组,心肌中ERβ、p-ERK的表达水平及T-AOC的含量均低于NC-siRNA AAV+E2+I/R组(P＜0.05)。结论: 雌二醇对去卵巢大鼠心肌I/R损伤具有保护作用,该作用与促进ERβ介导ERK通路激活、减轻炎症反应及氧化应激反应有关。.

To investigate the mechanism of shear stress on endothelial cell dysfunction for providing a theoretical basis for the reduction of arteriovenous fistula dysfunction. The in vitro parallel plate flow chamber was used to form different forces and shear stress to mimic the hemodynamic changes in human umbilical vein endothelial cells, and the expression and distribution of krüppel-like factor 2 (KLF2), caveolin-1 (Cav-1), p-extracellular regulated protein kinase (p-ERK), and endothelial nitric oxide synthase (eNOS) were detected by immunofluorescence and real-time quantitative polymerase chain reaction. With the prolongation of the shear stress action time, the expression of KLF2 and eNOS increased gradually, while the expression of Cav-1 and p-ERK decreased gradually. In addition, after cells were exposed to oscillatory shear stress (OSS) and low shear stress, the expression of KLF2, Cav-1, and eNOS decreased and the expression of p-ERK increased. The expression of KLF2 increased gradually with the prolongation of action time, but it was still obviously lower than that of high shear stress. Following the block of Cav-1 expression by methyl β-cyclodextrin, eNOS expression decreased, and KLF2 and p-ERK expression increased. OSS may lead to endothelial cell dysfunction by Cav-1-mediated KLF2/eNOS/ERK signaling pathway.

OBJECTIVE: Cardiac remodeling is a common pathological change in various cardiovascular diseases and can ultimately result in heart failure. Thus, there is an urgent need for more effective strategies to aid in cardiac protection. Our previous work found that sphingosine-1-phosphate (S1P) could ameliorate cardiac hypertrophy. In this study, we aimed to investigate whether S1P could prevent cardiac fibrosis and the associated mechanisms in cardiac remodeling.
METHODS: Eight-week-old male C57BL/6 mice were randomly divided into a sham, transverse aortic constriction (TAC) or a TAC+S1P treatment group.
RESULTS: We found that S1P treatment improved cardiac function in TAC mice and that the cardiac fibrosis ratio in the TAC+S1P group was significantly lower and was accompanied by a decrease in α-smooth muscle actin (α-SMA) and collagen type I (COL I) expression compared with the TAC group. We also found that one of the key S1P enzymes, sphingosine kinase 2 (SphK2), which was mainly distributed in cytoblasts, was downregulated in the cardiac remodeling case and recovered after S1P treatment in vivo and in vitro. In addition, our in vitro results showed that S1P treatment activated extracellular regulated protein kinases (ERK) phosphorylation mainly through the S1P receptor 2 (S1PR2) and spurred p-ERK transposition from the cytoplasm to cytoblast in H9c2 cells exposed to phenylephrine.
CONCLUSIONS: These findings suggest that SphK2 and the S1PR2/ERK pathway may participate in the anti-remodeling effect of S1P on the heart. This work therefore uncovers a novel potential therapy for the prevention of cardiac remodeling.

The gut microbiota is a complex group of microorganisms that is not only closely related to intestinal immunity but also affects the whole immune system of the body. Antimicrobial peptides and reactive oxygen species participate in the regulation of gut microbiota homeostasis in invertebrates. However, it is unclear whether nitric oxide, as a key mediator of immunity that plays important roles in antipathogen activity and immune regulation, participates in the regulation of gut microbiota homeostasis. In this study, we identified a nitric oxide synthase responsible for NO production in the shrimp Marsupenaeus japonicus. The expression of Nos and the NO concentration in the gastrointestinal tract were increased significantly in shrimp orally infected with Vibrio anguillarum. After RNA interference of Nos or treatment with an inhibitor of NOS, L-NMMA, NO production decreased and the gut bacterial load increased significantly in shrimp. Treatment with the NO donor, sodium nitroprusside, increased the NO level and reduced the bacterial load significantly in the shrimp gastrointestinal tract. Mechanistically, V. anguillarum infection increased NO level via upregulation of NOS and induced phosphorylation of ERK. The activated ERK phosphorylated the NF-κB-like transcription factor, dorsal, and caused nuclear translocation of dorsal to increase expression of antimicrobial peptides (AMPs) responsible for bacterial clearance. In summary, as a signaling molecule, NOS-produced NO regulates intestinal microbiota homeostasis by promoting AMP expression against infected pathogens via the ERK-dorsal pathway in shrimp.

P53 and DNA damage-regulated gene1 (PDRG1) is overexpressed in diverse carcinomas. Here, we discover that PDRG1 is overexpressed in glioblastoma multiforme (GBM). However, the clinical significance, biological role, and underlying molecular mechanisms of PDRG1 in GBM remain unclear. PDRG1 was aberrantly overexpressed in glioma, especially prevalent in GBM, and correlated with poor clinicopathologic features of glioma. The risk score, operational feature curve analysis, Kaplan-Meier curve, and univariate and multivariate Cox regression analysis indicated that PDRG1 was an independent prognostic indicator and significantly correlates with disease progression of glioma. A prognostic nomogram was constructed to predict the survival risk of individual patients. The function and pathway enrichment analysis of PDRG1 in The Cancer Genome Atlas cohort was performed. PDRG1 knockdown significantly inhibited the migration and proliferation of GBM cells in vitro and in vivo. Transcriptome sequencing analysis of PDRG1 knockdown U-118 MG(U118) cells indicated that biological regulation adhesion, growth and death, cell motility, cell adhesion molecular and proteoglycans in cancer were significantly enriched. Importantly, we found that the expression of adhesion molecule cluster of differentiation 44 (CD44) was regulated by PDRG1 in GBM. We found that PDRG1 promoted the migration and proliferation of GBM cells via the mitogen-activated protein kinase kinase (MEK)/extracellular regulated protein kinase (ERK)/CD44 pathway. Our findings provide proof that PDRG1 upregulation predicts progression and poor prognosis in human gliomas, especially in isocitrate dehydrogenase (IDH) wt glioma patients. The study provides new evidence that PDRG1 regulates the expression of CD44 in GBM cells and might promote the migration and proliferation via the MEK/ERK/CD44pathway. PDRG1 might be a novel diagnostic indicator and promising therapeutic target for GBM.

Ferroptosis, a new type of programmed cell death discovered in recent years, plays an important role in many neurodegenerative diseases. N2L is a novel lipoic acid-niacin dimer regulating lipid metabolism with multifunction, including antioxidant effect. It also exerts neuroprotective effects against glutamate- or β-amyloid (Aβ) -induced cell death. Because reactive oxygen species (ROS) play an essential role in ferroptosis, we hypothesize that N2L might protect cells from ferroptosis. Here, we investigated the protective effect of N2L and the underlying mechanism(s) under RAS-selective lethality 3 (RSL3) treatment in HT22 cells. RSL3 decreased the cell viability and induced excessive accumulation of ROS in HT22 cells. N2L pretreatment effectively protected HT22 cells against lipid peroxidation. What\'s more, N2L recovered glutathione peroxidase 4 (GPX4) expression and blocked the increase of Cyclooxygenase-2 (cox-2) and acyl-CoA synthetase long-chain family member 4 (ACSL4) protein expressions. Moreover, N2L also significantly prevented Ferritin Heavy Chain 1 (FTH1) from downregulation and maintained iron homeostasis. Finally, N2L pretreatment could decrease c-Jun N-terminal kinase (JNK) / extracellular regulated protein kinases (ERK) activation induced by RSL3. Taken together, our results showed that N2L could protect HT22 cells from RSL3-induced ferroptosis through decreasing lipid peroxidation and JNK/ERK activation. And N2L could be a ferroptosis inhibitor for the therapy of ferroptosis-related diseases, such as Alzheimer\'s disease.

Gold nanoparticles (AuNPs) are extensively utilized in biomedical fields. However, their potential interaction with host cells has not been comprehensively elucidated. In this study, we demonstrated a size-dependent effect of AuNPs to synergize with bacterial lipopolysaccharide (LPS) in promoting neutrophil extracellular traps (NETs) release in human peripheral neutrophils. Mechanistically, LPS was more efficient to contact with 10 nm AuNPs and promote their uptake in neutrophils compared to 40 and 100 nm AuNPs, leading to a synergistic upregulation of class A scavenger receptor (SRA) which mediated AuNPs uptake and triggered activation of extracellular regulated protein kinase (ERK) and p38. Blocking SRA or inhibiting ERK and p38 activation remarkably abrogated the effect of AuNPs and LPS to induce NETs formation. Further experiments demonstrated that AuNPs and LPS augmented the production of cytosolic reactive oxygen species (ROS) in p38 and ERK dependent manner, through upregulating and activating NADPH oxidase 2 (NOX2). Accordingly, scavenging of ROS or inhibiting the NOX2 dampened NETs release induced by combined AuNPs and LPS treatment. AuNPs and LPS also synergized to upregulate reactive oxygen species modulator 1 (ROMO1) via activating ERK, thereby increasing mitochondrial ROS generation and promoting the release of NETs. In summary, we provide new evidences about the synergy of AuNPs and LPS to augment cellular responses in neutrophils, which implicates the need to consider the amplifying effect by pathogenic stimuli when utilizing nanomaterials in infectious or inflammatory conditions.

Over-expression of angiotensin II (Ang II) is an important reason for the development of chronic kidney disease. Calycosin is the active component of traditional Chinese medicine astragali radix. The present work aims to explore whether calycosin could affect the growth and apoptosis ability of the Ang II treated glomerular mesangial cells and the underlying mechanism. Human glomerular mesangial cells (GMCs) were cultured and treated by Ang II and 0, 0.1, 1, or 10 µM calycosin, and the viability and proliferation of the cells were determined by methyl thiazolyl tetrazolium (MTT) and 5-ethynil-2\'-deoxyuridine (EdU) staining; moreover, the apoptosis of the cells was examined by flow cytometry assay; furthermore, the expression levels of extracellular signal-regulated kinase (ERK), p-ERK, anti-apoptotic factor Bcl-2, as well as pro-apoptotic factor Bax have been examined by Western blot (WB) methods; finally, the expression of autophagic markers in each group was examined by WB and immunocytochemistry methods. We found that Ang II increased viability and proliferation, meanwhile inhibited apoptosis of the GMCs; furthermore, 1 and 10 µM calycosin significantly inhibited the growth and promoted the apoptosis of the GMCs treated by Ang II; moreover, calycosin also inhibited ERK signaling in mesangial cells activated by Ang II treatment; Finally, calycosin could inhibit Ang II induced autophagy of GMCs in a dose-dependent manner. In conclusion, calycosin may alleviate Ang II-induced pro-proliferative and anti-apoptotic effects on glomerular mesangial cells at least partially via inhibiting autophagy and ERK signaling pathway, suggesting that calycosin may function as a potential alternative medication for the management of chronic kidney diseases.