Reactive Oxygen Species Pathway Research Articles

Research progress on mechanisms of acupuncture and moxibustion underlying improvement of oxidative stress.

Oxidative stress is associated with a variety of disease pathologies, it may lead to mitochondrial dysfunction, damage of impaired DNA repairment, cell damage or apoptosis. Acupuncture and moxibustion therapy has been proved to have a role in reducing oxidative stress in organisms under pathological conditions. In the present paper, we collected literatures in both English and Chinese from domestic and foreign databases on the mechanisms of acupuncture and moxibustion underlying amelioration of oxidative stress over the past 5 years, and analyzed the link between acupuncture-moxibustion intervention and redox biology from four aspects： 1) regulation of the production of reactive oxygen species (ROS), 2) affecting antioxidant enzyme-related pathways to reduce ROS, 3) repairing proteins, lipids and DNAs attacked by ROS, and 4) inhibiting downstream apoptosis or autophagy of ROS pathway. By summarizing and prospecting such antioxidant mechanisms, this paper may provide some basis and ideas for in-depth mechanism research on acupuncture and moxibustion to improve oxidative stress and related diseases.

Metaplastic regeneration in the mouse stomach requires a reactive oxygen species pathway

In pyloric metaplasia, mature gastric chief cells reprogram via an evolutionarily conserved process termed paligenosis to re-enter the cell cycle and become spasmolytic polypeptide-expressing metaplasia (SPEM) cells. Here, we use single-cell RNA sequencing (scRNA-seq) following injury to the murine stomach to analyze mechanisms governing paligenosis at high resolution. Injury causes induced reactive oxygen species (ROS) with coordinated changes in mitochondrial activity and cellular metabolism, requiring the transcriptional mitochondrial regulator Ppargc1a (Pgc1α) and ROS regulator Nf2el2 (Nrf2). Loss of the ROS and mitochondrial control in Ppargc1a-/- mice causes the death of paligenotic cells through ferroptosis. Blocking the cystine transporter SLC7A11(xCT), which is critical in lipid radical detoxification through glutathione peroxidase 4 (GPX4), also increases ferroptosis. Finally, we show that PGC1α-mediated ROS and mitochondrial changes also underlie the paligenosis of pancreatic acinar cells. Altogether, the results detail how metabolic and mitochondrial changes are necessary for injury response, regeneration, and metaplasia in the stomach.

Evolution of the WRKY Family in Angiosperms and Functional Diversity under Environmental Stress.

The transcription factor is an essential factor for regulating the responses of plants to external stimuli. The WRKY protein is a superfamily of plant transcription factors involved in response to various stresses (e.g., cold, heat, salt, drought, ions, pathogens, and insects). During angiosperm evolution, the number and function of WRKY transcription factors constantly change. After suffering from long-term environmental battering, plants of different evolutionary statuses ultimately retained different numbers of WRKY family members. The WRKY family of proteins is generally divided into three large categories of angiosperms, owing to their conserved domain and three-dimensional structures. The WRKY transcription factors mediate plant adaptation to various environments via participating in various biological pathways, such as ROS (reactive oxygen species) and hormone signaling pathways, further regulating plant enzyme systems, stomatal closure, and leaf shrinkage physiological responses. This article analyzed the evolution of the WRKY family in angiosperms and its functions in responding to various external environments, especially the function and evolution in Magnoliaceae plants. It helps to gain a deeper understanding of the evolution and functional diversity of the WRKY family and provides theoretical and experimental references for studying the molecular mechanisms of environmental stress.

Therapeutic targeting nudix hydrolase 1 creates a MYC-driven metabolic vulnerability.

Tumor cells must rewire nucleotide synthesis to satisfy the demands of unbridled proliferation. Meanwhile, they exhibit augmented reactive oxygen species (ROS) production which paradoxically damages DNA and free deoxy-ribonucleoside triphosphates (dNTPs). How these metabolic processes are integrated to fuel tumorigenesis remains to be investigated. MYC family oncoproteins coordinate nucleotide synthesis and ROS generation to drive the development of numerous cancers. We herein perform a Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-based functional screen targeting metabolic genes and identified nudix hydrolase 1 (NUDT1) as a MYC-driven dependency. Mechanistically, MYC orchestrates the balance of two metabolic pathways that act in parallel, the NADPH oxidase 4 (NOX4)-ROS pathway and the Polo like kinase 1 (PLK1)-NUDT1 nucleotide-sanitizing pathway. We describe LC-1-40 as a potent, on-target degrader that depletes NUDT1 in vivo. Administration of LC-1-40 elicits excessive nucleotide oxidation, cytotoxicity and therapeutic responses in patient-derived xenografts. Thus, pharmacological targeting of NUDT1 represents an actionable MYC-driven metabolic liability.

Activation of astrocytes by ANXA2-derived extracellular vesicles from lung cancer cells affects aggressiveness, immunotherapy response and microenvironment of lung cancer

BackgroundANXA2 has been extensively documented in relation to cancer. Nevertheless, the involvement of ANXA2 in lung carcinoma remains uncertain. MethodsData from The Cancer Genome Atlas (TCGA) database was downloaded using open-access methods. The examination of publicly available data was conducted utilizing the R software. The mRNA level of specific molecules was detected using Real-time Quantitative PCR (qPCR). The protein level of specific molecules was detected using the Western blot assay. The cell proliferation ability of cancer cells was assessed using the CCK8 assay. The invasion and migration capability of cancer cells was assessed using the Transwell assay. Validation of exosomes extraction was conducted using electron microscopy and particle size analysis. ResultsIn this study, based on series experiments, we found that ANXA2 can promote the activation of neuroastrocytes cells CP-H122 through the exosome pathway. Also, we found that ANXA2 can be transmitted from A549 cells to CP-H122 through the exosomes pathway and further promote the activation of CP-H122. Activated CP-H122 cells further enhance the proliferation, invasion and metastasis of A549 cells. Meanwhile, we performed transcriptome sequencing to explore the downstream genes of ANXA2 to screen potential targets for follow-up studies. Analysis based on public data showed that ANXA2 was related to the worse survival performance and clinical features of lung cancer. Gene set enrichment analysis based on the Hallmark gene set indicated that the patient with high ANXA2 expression might have a higher activity of the apical surface, reactive oxygen species pathway, angiogenesis, TGF-β signaling, MYC target, but lower activity of pancreas-β cells. More important, our results showed that ANXA2 can affects immunotherapy response and reshape immune microenvironment of lung cancer. ConclusionsThis study demonstrates that ANXA2 activates CP-H122 cells, affects A549 cell behavior, and impacts lung cancer prognosis and immunotherapy response.

Benzoylaconitine: A promising ACE2-targeted agonist for enhancing cardiac function in heart failure

Benzoylaconitine is a natural product in the treatment of cardiovascular disease. However, its pharmacological effect, direct target protein, and molecular mechanisms for the treatment of heart failure are unclear. In this study, benzoylaconitine inhibited Ang II-induced cell hypertrophy and fibrosis in rat primary cardiomyocytes and rat fibroblasts, while attenuating cardiac function and cardiac remodeling in TAC mice. Using the limited proteolysis-mass spectrometry (LiP-MS) method, the angiotensin-converting enzyme 2 (ACE2) was confirmed as a direct binding target of benzoylaconitine for the treatment of heart failure. In ACE2-knockdown cells and ACE2−/− mice, benzoylaconitine failed to ameliorate cardiomyocyte hypertrophy, fibrosis, and heart failure. Online RNA-sequence analysis indicated p38/ERK-mediated mitochondrial reactive oxygen species (ROS) and nuclear factor kappa B (NF-κB) activation are the possible downstream molecular mechanisms for the effect of BAC-ACE2 interaction. Further studies in ACE2-knockdown cells and ACE2−/− mice suggested that benzoylaconitine targeted ACE2 to suppress p38/ERK-mediated mitochondrial ROS and NF-κB pathway activation. Our findings suggest that benzoylaconitine is a promising ACE2 agonist in regulating mitochondrial ROS release and inflammation activation to improve cardiac function in the treatment of heart failure.

PTCH1 mutation as a potential predictive biomarker for immune checkpoint inhibitors in gastrointestinal cancer.

Immune checkpoint inhibitors (ICIs) have become prominent therapies for gastrointestinal cancer (GC). However, it is urgent to screen patients who can benefit from ICIs. Protein patched homolog 1 (PTCH1) is a frequently altered gene in GC. We attempt to explore the association between PTCH1 mutation and immunotherapy efficacy. The Memorial Sloan Kettering Cancer Center (MSKCC) cohort (n = 236) with GC (esophageal, gastric and colorectal cancers) patients receiving ICIs was used for discovery and the Peking University Cancer Hospital (PUCH) GC cohort (n = 92) was used for validation. Overall survival (OS) and tumor mutational burden (TMB) of the PTCH1 mutant-type (PTCH1-MUT) and PTCH1 wild-type (PTCH1-WT) groups were compared. Furthermore, GC data were collected from The Cancer Genome Atlas to assess the potential mechanisms. In the MSKCC cohort, PTCH1-MUT group showed significantly better OS (P = 0.017) and higher TMB. Multivariate analysis showed that PTCH1 mutation was associated with better OS. In the PUCH cohort, PTCH1-MUT group showed significantly longer OS (P = 0.036) and progression-free survival, and higher durable clinical benefit and TMB. Immune cell infiltration analysis revealed that PTCH1-MUT group had significantly higher distributions of CD8 T cells, CD4 T cells, NK cells, mast cells and M1 cells. The PTCH1-MUT group showed significantly higher expression of most immune-related genes. Gene set enrichment analysis showed that the PTCH1-MUT group had enriched INF-γ response, INF-α response, glycolysis and reactive oxygen species pathway gene sets. PTCH1 mutation may represent a potential biomarker for predicting ICIs response in GC. Nevertheless, prospective cohort studies should be performed to further validate our results.

Catalase regulation during plant-virus-vector interaction.

Plant-virus-host interaction is a complex process involving several players. A constant arms race between the hosts and viruses has led to their co-evolution. Reactive oxygen species (ROS) are important signaling molecules that regulate plant growth, development, and stress responses. Barley yellow dwarf virus (BYDV) has a wide host range and infects several plant species such as barley, rice, oats, wheat, etc. A recent study by Tian et al. (2024) has highlighted that the movement protein (MP) of BYDV is involved in manipulation of the host ROS pathway to promote viral multiplication as well as transmission. The findings display the multifaceted role of a viral protein that is otherwise involved in movement. The limited coding ability of viruses is compensated by their proteins having multiple roles in the modulation of several different host molecular pathways. This is one of the key reasons for viruses being successful pathogens despite their limited coding ability.

Inhibition of palmitoyltransferase ZDHHC12 sensitizes ovarian cancer cells to cisplatin through ROS-mediated mechanisms.

Platinum-based therapies have revolutionized the treatment of high-grade serous ovarian cancer (HGSOC). However, high rates of disease recurrence and progression remain a major clinical concern. Impaired mitochondrial function and dysregulated reactive oxygen species (ROS), hallmarks of cancer, hold potential as therapeutic targets for selectively sensitizing cisplatin treatment. Here, we uncover an oncogenic role of the palmitoyltransferase ZDHHC12 in regulating mitochondrial function and ROS homeostasis in HGSOC cells. Analysis of The Cancer Genome Atlas (TCGA) ovarian cancer data revealed significantly elevated ZDHHC12 expression, demonstrating the strongest positive association with ROS pathways among all ZDHHC enzymes. Transcriptomic analysis of independent ovarian cancer datasets and the SNU119 cell model corroborated this association, highlighting a strong link between ZDHHC12 expression and signature pathways involving mitochondrial oxidative metabolism and ROS regulation. Knockdown of ZDHHC12 disrupted this association, leading to increased cellular complexity, ATP levels, mitochondrial activity, and both mitochondrial and cellular ROS. This dysregulation, achieved by the siRNA knockdown of ZDHHC12 or treatment with the general palmitoylation inhibitor 2BP or the fatty acid synthase inhibitor C75, significantly enhanced cisplatin cytotoxicity in 2D and 3D spheroid models of HGSOC through ROS-mediated mechanisms. Markedly, ZDHHC12 inhibition significantly augmented the anti-tumor activity of cisplatin in an ovarian cancer xenograft tumor model, as well as in an ascites-derived organoid line of platinum-resistant ovarian cancer. Our data suggest the potential of ZDHHC12 as a promising target to improve the outcome of HGSOCs in response to platinum-based chemotherapy.

Identification ATP5F1D as a Biomarker Linked to Diagnosis, Prognosis, and Immune Infiltration in Endometrial Cancer Based on Data-Independent Acquisition (DIA) Analysis.

In developed countries, endometrial cancer (EC) is the most prevalent gynecological cancer. ATP5F1D is a subunit of ATP synthase, as well as an important component of the mitochondrial electron transport chain (ETC). ETC plays a compelling role in carcinogenesis. To date, little is known about the role of ATP5F1D in EC. We undertook data-independent acquisition mass spectrometry (DIA-MS) of 20 EC patients, comprising 10 high-grade and 10 low-grade cancer tissues. Biological functions of differentially expressed genes (DEGs) were analyzed by GO and KEGG. The expression level, clinicopathological features, diagnostic potency, prognostic value, RNA modifications, immune characteristics, and therapy response of ATP5F1D were investigated. In total, 77 DEGs were acquired by DIA analysis, which were closely related to regulating immune response and metabolic pathways. Among the five genes (NDUFB8, SLC26A2, RAF1, ATP5F1D, and GSTM5) involving in reactive oxygen species pathway, ATP5F1D showed the most significant differential expression (2.903-fold change). We found ATP5F1D had a high diagnostic value and was associated with a favorable prognosis in EC patients. After analyzing the RNA modifications of ATP5F1D, revealing a negative regulation between them. Additionally, ATP5F1D was closely related to tumor immune infiltration. Our results suggested T-cell dysfunction and TAM-M2 polarization might be the important mechanisms of ATP5F1D to facilitate tumor immune escape. Noticeably, EC patients with ATP5F1D-high expression had better immune treatment responses and were more sensitive to chemotherapy drugs. ATP5F1D can be used as a biomarker for diagnosis, prognosis, and immune infiltration of EC, and offers a crucial reference for personalized treatment of EC patients.

NQO1 Mediates Lenvatinib Resistance by Regulating ROS-induced Apoptosis in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-associated death worldwide. As a first-line drug for advanced HCC treatment, lenvatinib faces a significant hurdle due to the development of both intrinsic and acquired resistance among patients, and the underlying mechanism remains largely unknown. The present study aims to identify the pivotal gene responsible for lenvatinib resistance in HCC, explore the potential molecular mechanism, and propose combinatorial therapeutic targets for HCC management. Cell viability and colony formation assays were conducted to evaluate the sensitivity of cells to lenvatinib and dicoumarol. RNA-Seq was used to determine the differences in transcriptome between parental cells and lenvatinib-resistant (LR) cells. The upregulated genes were analyzed by GO and KEGG analyses. Then, qPCR and Western blotting were employed to determine the relative gene expression levels. Afterwards, the intracellular reactive oxygen species (ROS) and apoptosis were detected by flow cytometry. PLC-LR and Hep3B-LR were established. There was a total of 116 significantly upregulated genes common to both LR cell lines. The GO and KEGG analyses indicated that these genes were involved in oxidoreductase and dehydrogenase activities, and reactive oxygen species pathways. Notably, NAD(P)H:quinone oxidoreductase 1 (NQO1) was highly expressed in LR cells, and was involved in the lenvatinib resistance. The high expression of NQO1 decreased the production of ROS induced by lenvatinib, and subsequently suppressed the apoptosis. The combination of lenvatinib and NQO1 inhibitor, dicoumarol, reversed the resistance of LR cells. The high NQO1 expression in HCC cells impedes the lenvatinib-induced apoptosis by regulating the ROS levels, thereby promoting lenvatinib resistance in HCC cells.

Hypoxia and intra-complex genetic suppressors rescue complex I mutants by a shared mechanism

The electron transport chain (ETC) of mitochondria, bacteria, and archaea couples electron flow to proton pumping and is adapted to diverse oxygen environments. Remarkably, in mice, neurological disease due to ETC complex I dysfunction is rescued by hypoxia through unknown mechanisms. Here, we show that hypoxia rescue and hyperoxia sensitivity of complex I deficiency are evolutionarily conserved to C.elegans and are specific to mutants that compromise the electron-conducting matrix arm. We show that hypoxia rescue does not involve the hypoxia-inducible factor pathway or attenuation of reactive oxygen species. To discover the mechanism, we use C.elegans genetic screens to identify suppressor mutations in the complex I accessory subunit NDUFA6/nuo-3 that phenocopy hypoxia rescue. We show that NDUFA6/nuo-3(G60D) or hypoxia directly restores complex I forward activity, with downstream rescue of ETC flux and, in some cases, complex I levels. Additional screens identify residues within the ubiquinone binding pocket as being required for the rescue by NDUFA6/nuo-3(G60D) or hypoxia. This reveals oxygen-sensitive coupling between an accessory subunit and the quinone binding pocket of complex I that can restore forward activity in the same manner as hypoxia.

Roles of ROS and redox in regulating cell-to-cell communication: Spotlight on viral modulation of redox for local spread.

Reactive oxygen species (ROS) are important signalling molecules that influence many aspects of plant biology. One way in which ROS influence plant growth and development is by modifying intercellular trafficking through plasmodesmata (PD). Viruses have evolved to use PD for their local cell-to-cell spread between plant cells, so it is therefore not surprising that they have found ways to modulate ROS and redox signalling to optimise PD function for their benefit. This review examines how intracellular signalling via ROS and redox pathways regulate intercellular trafficking via PD during development and stress. The relationship between viruses and ROS-redox systems, and the strategies viruses employ to control PD function by interfering with ROS-redox in plants is also discussed.

Specific cell subclusters of dental pulp stem cells respond to distinct pathogens through the ROS pathway.

Microbial pathogens invade various human organs, including the oral cavity. Candida albicans (C.a) and Streptococcus mutans (S.m) served respectively as representative oral pathogenic fungi and bacteria to stimulate dental pulp stem cells (DPSCs) and to screen the DPSC subcluster that specifically responded to fungal infection. DPSCs were obtained from the impacted third molars of six healthy subjects. Then, cells were mixed and divided into three samples, two of which were stimulated with C.a and S.m, respectively; the third sample was exposed to cell medium only (Ctrl). Single-cell mRNA sequencing analysis of treated DPSCs was performed. DPSCs were composed of four major clusters of which one, DPSC.7, exhibited unique changes compared to those of other subclusters. The DPSC.7 cell percentage of the C.a sample was twice those of the Ctrl and S.m samples. DPSC.7 cells expressed genes associated with the response to reactive oxygen species (ROS) response. DPSC.7 subgroup cells established characteristic aggregation under the stimulation of different pathogens in UMAP. The MAPK/ERK1/2 and NF-κB pathways were up-regulated, DUSP1/5/6 expressions were suppressed, FOS synthesis was activated, the immune-related pathway was induced, and the levels of cytokines, including IL-6 and CCL2, were up-regulated in DPSC.7 cells when stimulated with C.a. Our study analyzed the cellular and molecular properties of DPSCs infected by oral fungi and bacteria with single-cell RNA sequencing. A subcluster of DPSCs responded specifically to infections with different pathogens, activating the MAPK and NF-κB pathways to induce immune responses via the ROS pathway. This suggests novel treatment strategies for fungal infections.

The Protection of EGCG Against 6-OHDA-Induced Oxidative Damage by Regulating PPARγ and Nrf2/HO-1 Signaling.

6-Hydroxydopamine (6-OHDA) is a classic neurotoxin that has been widely used in Parkinson's disease research. 6-OHDA can increase intracellular reactive oxygen species (ROS) and can cause cell damage, which can be attenuated with (-)-Epigallocatechin-3-gallate (EGCG) treatment. However, the mechanism by which EGCG alters the 6-OHDA toxicity remains unclear; In this study, we found 6-OHDA (25 μM) alone increased intracellular ROS concentration in N27 cells, which was attenuated by pretreating with EGCG (100 μM). We evaluated the intracellular oxidative damage by determining the level of thiobarbituric acid reactive substances (TBARS) and protein carbonyl content. 6-OHDA significantly increased TBARS by 82.7% (P < .05) and protein carbonyl content by 47.8 (P < .05), compared to the control. Pretreatment of EGCG decreased TBARS and protein carbonyls by 36.4% (P < .001) and 27.7% (P < .05), respectively, compared to 6-OHDA alone treatment. Antioxidant effect was tested with E2-related factor 2 (Nrf2), heme oxygenase-1(HO-1) and peroxisome-proliferator activator receptor γ (PPARγ) expression. 6-OHDA increased Nrf2 expression by 69.6% (P < .001), HO-1 by 173.3% (P < .001), and PPARγ by 122.7% (P < .001), compared with untreatment. EGCG pretreatment stabilized these alterations induced by 6-OHDA. Our results suggested that the neurotoxicity of 6-OHDA in N27 cells was associated with ROS pathway, whereas pretreatment of EGCG suppressed the ROS generation and deactivated the Nrf2/HO-1 and PPARγ expression.

SIRT1-regulated ROS generation activates NMDAR2B phosphorylation to promote central sensitization and allodynia in a male chronic migraine rat model.

Central sensitization is one of the pivotal pathological mechanisms in chronic migraine (CM). Silent information regulator 1 (SIRT1) was shown to be involved in CM, but its specific mechanism is unclear. Reactive oxygen species (ROS) are increasingly regarded as important signaling molecules in several models of pain. However, studies about the role of ROS in the central sensitization of CM model are rare. We thus explored the specific process of SIRT1 involvement in the central sensitization of CM, focusing on the ROS pathway. Inflammatory soup was repeatedly administered to male Sprague-Dawley rats to establish a CM model. The SIRT1 expression level in trigeminal nucleus caudalis (TNC) tissues was assessed by qRT-PCR and Western blotting analysis. The levels of ROS were detected by a Tissue Reactive Oxygen Detection Kit, DHE staining, and the fluorescence signal intensity of 8-OHdG. A ROS scavenger (tempol), a SIRT1 activator (SRT1720), a SIRT1 inhibitor (EX527), and a mitochondrial fission inhibitor (Mdivi-1) were used to investigate the specific molecular mechanisms involved. NMDAR2B, CGRP, ERK, and mitochondrial fission-related protein were evaluated by Western blotting, and the CGRP level in frozen sections of the TNC was detected via immunofluorescence staining. After repeated inflammatory soup infusion and successful establishment of the CM rat model, SIRT1 expression was found to be significantly reduced, accompanied by elevated ROS levels. Treatment with Tempol, SRT1720, or Mdivi-1 alleviated allodynia and reduced the increase in NMDAR2B phosphorylation and CGRP and ERK phosphorylation in the CM rat. In contrast, EX527 had the opposite effect in CM rat. SRT1720 and EX527 decreased and increased ROS levels, respectively, in CM rats, and tempol reversed the aggravating effect of EX527 in CM rats. Furthermore, the regulatory effect of SIRT1 on ROS may include the involvement of the mitochondrial fission protein DRP1. The results indicate the importance of SIRT1 in CM may be due to its role in regulating the production of ROS, which are involved in modulating central sensitization in CM. These findings could lead to new ideas for CM treatment with the use of SIRT1 agonists and antioxidants.

Single-Cell Sequencing Combined with Transcriptome Sequencing to Explore the Molecular Mechanisms Related to Psoriasis.

Psoriasis, a chronic and recurrent inflammatory skin disease, current treatments can only alleviate its symptoms. There is still no complete cure. Although increasing research supports the therapeutics to be better, the common mechanism of its occurrence is still not fully elucidated. Our study is about further explore the molecular mechanism of the occurrence of this disease. The gene expression profiles of psoriasis (GSE151177, GSE41664, GSE30999) were downloaded from the Gene Expression Omnibus (GEO) database. After identifying the common differentially expressed genes (DEGs) of psoriasis using R software, three kinds of analyses were performed,namely WGCNA, GWAS Analysis, Drug Target Prediction. A total of 14 common DEGs was selected for subsequent analyses. Our Drug Target Prediction analysis revealed that the expression profiles influenced by certain drugs, including methotrexate, budesonide, amino purvalanol-a, and selumetinib, exhibited negative correlations with the disease-perturbed expression profiles. Finally, It was found that S100A4, JAML, TRAF3IP3, MIAT, IL7R, and KLRB1 were prominently expressed in the immune pathway related to allograft rejection. In the metabolic pathway, oxidative phosphorylation showed high expression levels, while the reactive oxygen species pathway was notably expressed in the signaling pathways domain. Our study reveals the potential drugs and pathogenesis of psoriasis. These potential pathway and hub genes may provide new ideas for further mechanism research.

Evaluation of Pm2.5 Influence on Human Lung Cancer Cells Using a Microfluidic Platform.

In this study, we developed a microfluidic device that is able to monitor cell biology under continuous PM2.5 treatment. The effects of PM2.5 on human alveolar basal epithelial cells, A549 cells, and uncovered several significant findings were investigated. The results showed that PM2.5 exposure did not lead to a notable decrease in cell viability, indicating that PM2.5 did not cause cellular injury or death. However, the study found that PM2.5 exposure increased the invasion and migration abilities of A549 cells, suggesting that PM2.5 might promote cell invasiveness. Results of RNA sequencing revealed 423 genes that displayed significant differential expression in response to PM2.5 exposure, with a particular focus on pathways associated with the generation of reactive oxygen species (ROS) and mitochondrial dysfunction. Real-time detection demonstrated an increase in ROS production in A549 cells after exposure to PM2.5. JC1 assay, which indicated a loss of mitochondrial membrane potential (ΔΨm) in A549 cells exposed to PM2.5. The disruption of mitochondrial membrane potential further supports the detrimental effects of PM2.5 on A549 cells. These findings highlight several adverse effects of PM2.5 on A549 cells, including enhanced invasion and migration capabilities, altered gene expression related to ROS pathways, increased ROS production and disruption of mitochondrial membrane potential. These findings contribute to our understanding of the potential mechanisms through which PM2.5 can impact cellular function and health.

Molecular characterization of a novel heat shock transcription factor gene TaHsfA2-11 and its overexpression improves thermotolerance in wheat

High temperature is a major constrait limiting the yield and quality of wheat. Wheat heat shock transcription factor (Hsf) plays important roles in regulating plant response to heat shock. In previous study, we found there are 82 Hsfs in wheat and TaHsfA2–11 expression was obviously upregulated by heat stress. In this study, we aim to investigate TaHsfA2–11 function and regulating mechanism in response to heat shock through genetic transformation into wheat Fielder. Gene expression analyses results showed that TaHsfA2–11 was expressed in all detected tissues and the most highly expressed level was in wheat mature roots. The expression level of TaHsfA2–11 was strongly upregulated by heat shock in wheat leaves. Subcellular localization results represented that TaHsfA2–11 is located to the nucleus. Transgenic wheat seedlings overexpressing TaHsfA2–11 showed stronger thermotolerance than the control Fielder after treated under 50 °C for 12 h. After heat shock, the TaHsfA2–11 overexpressing lines showed increased survival rate, chlorophyll content, POD (Peroxidase) activity, SOD (Superoxide dismutase) activity and photosynthetic rate, and decreased relative electrolyte leakage and MDA (malondialdehyde) content compared with Fielder. The results of RNA-sequence data demonstrated that TaHsfA2–11 can regulate many heat response genes, such as Hsp genes TaHsp16.6 and TaHsp21, ER (Endoplasmic reticulum) stress genes TaBiP2 and TaERDJ3A, photoprotectant for PSII gene TaELIPHV58, flavone biosynthesis related genes TaUGT-2A and TaPMaT, etc after heat stress. These results showed that TaHsfA2–11 can impove thermotolerance perhaps through effecting signal pathway of heat, ER stress, photosynthesis and ROS (Reactive Oxygen Species). The findings will provide useful gene resource for performing genetic modification of wheat thermotolerance in heat-resistant breeding.

Glycine-serine-rich effector PstGSRE4 in Puccinia striiformis f. sp. tritici targets and stabilizes TaGAPDH2 that promotes stripe rust disease.

Puccinia striiformis f. sp. tritici (Pst) secretes effector proteins that enter plant cells and manipulate host processes. In a previous study, we identified a glycine-serine-rich effector PstGSRE4, which was proven to regulate the reactive oxygen species (ROS) pathway by interacting with TaCZSOD2. In this study, we further demonstrated that PstGSRE4 interacts with wheat glyceraldehyde-3-phosphate dehydrogenase TaGAPDH2, which is related to ROS signalling. In wheat, silencing of TaGAPDH2 by virus-induced gene silencing increased the accumulation of ROS induced by the Pst virulent race CYR31. Overexpression of TaGAPDH2 decreased the accumulation of ROS induced by the avirulent Pst race CYR23. In addition, TaGAPDH2 suppressed Pst candidate elicitor Pst322-triggered cell death by decreasing ROS accumulation in Nicotiana benthamiana. Knocking down TaGAPDH2 expression attenuated Pst infection, whereas overexpression of TaGAPDH2 promoted Pst infection, indicating that TaGAPDH2 is a negative regulator of plant defence. In N. benthamiana, PstGSRE4 stabilized TaGAPDH2 through inhibition of the 26S proteasome-mediated destabilization. Overall, these results suggest that TaGAPDH2 is hijacked by the Pst effector as a negative regulator of plant immunity to promote Pst infection in wheat.