Reactive Oxygen Species Pathway Research Articles

Osteoprogenitor SFRP1 prevents exhaustion of hematopoietic stem cells via PP2A-PR72/130-mediated regulation of p300.

Remodeling of the bone marrow microenvironment in chronic inflammation and in aging reduces hematopoietic stem cell (HSC) function. To assess the mechanisms of this functional decline of HSC and find strategies to counteract it, we established a model in which the Sfrp1 gene was deleted in Osterix+ osteolineage cells (OS1Δ/Δ mice). HSC from these mice showed severely diminished repopulating activity with associated DNA damage, enriched expression of the reactive oxygen species pathway and reduced single-cell proliferation. Interestingly, not only was the protein level of Catenin beta-1 (bcatenin) elevated, but so was its association with the phosphorylated co-activator p300 in the nucleus. Since these two proteins play a key role in promotion of differentiation and senescence, we inhibited in vivo phosphorylation of p300 through PP2A-PR72/130 by administration of IQ-1 in OS1Δ/Δ mice. This treatment not only reduced the b-catenin/phosphop300 association, but also decreased nuclear p300. More importantly, in vivo IQ-1 treatment fully restored HSC repopulating activity of the OS1Δ/Δ mice. Our findings show that the osteoprogenitor Sfrp1 is essential for maintaining HSC function. Furthermore, pharmacological downregulation of the nuclear b-catenin/phospho-p300 association is a new strategy to restore poor HSC function.

Oxalate-induced apoptosis through ERS-ROS–NF-κB signalling pathway in renal tubular epithelial cell

BackgroundKidney stones are composed of approximately 70–80% calcium oxalate. However, the exact mechanism of formation of calcium oxalate kidney stones remains unclear. In this study, we investigated the roles of endoplasmic reticulum stress (ERS), reactive oxygen species (ROS), and the NF-κB signalling pathway in the pathogenesis of oxalate-induced renal tubular epithelial cell injury and its possible molecular mechanisms.MethodsWe established a model to evaluate the formation of kidney stones by intraperitoneal injection of glyoxylic acid solution into mice and assessed cell morphology, apoptosis, and the expression levels of ERS, ROS, and NF-κB signalling pathway-related proteins in mouse renal tissues. Next, we treated HK-2 cells with potassium oxalate to construct a renal tubular epithelial cell injury model. We detected the changes in autophagy, apoptosis, and mitochondrial membrane potential and investigated the ultrastructure of the cells by transmission electron microscopy. Western blotting revealed the expression levels of apoptosis and autophagy proteins; mitochondrial structural and functional proteins; and ERS, ROS, and NF-κB (p65) proteins. Lastly, we studied the downregulation of NF-κB activity in HK-2 cells by lentivirus interference and confirmed the interaction between the NF-κB signalling and ERS/ROS pathways.ResultsWe observed swelling of renal tissues, increased apoptosis of renal tubular epithelial cells, and activation of the ERS, ROS, and NF-κB signalling pathways in the oxalate group. We found that oxalate induced autophagy, apoptosis, and mitochondrial damage in HK-2 cells and activated the ERS/ROS/NF-κB pathways. Interestingly, when the NF-κB signalling pathway was inhibited, the ERS/ROS pathway was also inhibited.ConclusionOxalate induces HK-2 cell injury through the interaction between the NF-κB signalling and ERS/ROS pathways.

Granulocytic myeloid-derived suppressor cells to prevent and treat murine immune-mediated bone marrow failure

AbstractMyeloid-derived suppressor cells (MDSCs) are immature myeloid cells that originate in the bone marrow (BM) and have immunoregulatory functions. MDSCs have been implicated in the pathogenesis of several autoimmune diseases but have not been investigated in immune aplastic anemia (AA). We examined the roles of granulocytic-MDSCs (G-MDSCs) in murine models of human AA and BM failure (BMF). As both prophylaxis and therapy, BM-derived G-MDSCs improved pancytopenia and BM cellularity and suppressed BM T-cell infiltration in major histocompatibility complex (MHC)-matched C.B10 BMF mice. These effects were not obtained in the MHC-mismatched CByB6F1 AA model, likely because of MHC disparity between G-MDSCs and donor T cells. Single-cell RNA sequencing demonstrated that G-MDSCs downregulated cell cycle–related genes in BM-infiltrated T cells, consistent with suppression of T-cell proliferation by G-MDSCs through reactive oxygen species pathways. Clearance of G-MDSCs in the MHC-mismatched CByB6F1 model using anti-Ly6G antibody facilitated T cell–mediated BM destruction, suggesting an intrinsic immunosuppressive property of G-MDSCs. However, the same anti-Ly6G antibody in the MHC-matched C.B10 AA model mildly mitigated BMF, associated with expansion of an intermediate Ly6G population. Our results demonstrate that G-MDSC eradication and therapeutic efficacy are immune context-dependent.

Reactive molecular dynamics simulation on degradation of aflatoxin B1 by cold atmospheric plasmas

Aflatoxins pose a threat to humans and animals and are not easily degraded. Cold atmospheric plasma (CAP) can effectively decontaminate aflatoxins in foods. In this study, a Reactive Molecular Dynamics (RMD) simulation was carried out to examine the interactions of reactive oxygen species (ROS) produced in CAP and aflatoxin B1 (AFB1). The simulation results indicated that ROS (O atoms, OH radicals, and H2O2 molecules considered in present study) can reduce the toxicity of AFB1 by the addition reaction of the double C8C9 bond, the ring-opening reaction of the terminal furan ring, and the destruction of the lactone ring. The ketone carbonyl reduction and double CC bonds formation of cyclopentenone can also be observed in the simulation. The reaction pathways and the final products unveiled by simulation results agree well with the experimental observations, which clearly indicate that CAP can degrade AFB1 by destroying the key structures of AFB1 in a non-thermal way, and further suggest the optimized way to degrade aflatoxins in applications. Industrial relevanceReactive Molecular Dynamics simulations were applied to visualize the chemical damaging mechanism of AFB1 upon the impact of reactive oxygen species during food processing by cold atmospheric plasma (CAP). Such detailed information about the pathways of specific ROS is difficult to obtain experimentally. These results can be used to understand the structural changes at the atomic level that could provide theoretical instruction to industrialists. This work can also contribute to the optimization of process parameters to drive the improvement of operating conditions and the development of CAP sources in the food industry.

Engineering at Subatomic Scale: Achieving Selective Catalytic Pathways via Tuning of the Oxidation States in Functionalized Single-Atom Quantum Catalysts.

Regulating the catalytic pathways of single-atom sites in single atom catalysts (SACs) is an exciting debate at the moment, which has redirected the research towards understanding and modifying the single-atom catalytic sites through various strategies including altering the coordination environment of single atom for desirable outcomes as well as increasing their number. One useful aspect concerning the tunability of the catalytic pathways of SACs, which has been overlooked, is the oxidation state dynamics of the single atoms. In this study, iron single-atoms (FeSA) with variable oxidation states, dependent on the precursors, are harnessed inside a nitrogen-rich functionalized carbon quantum dots (CQDs) matrix via a facile one-step and low-temperature synthesis process. Dynamic electronic properties are imparted to the FeSAs by the simpler carbon dots matrix of CQDs in order to achieve the desired catalytic pathways of reactive oxygen species (ROS) generation in different environments, which are explored experimentally and theoretically for an in-depth understanding of the redox chemistry that drives the alternative catalytic pathways in FeSA@CQDs. These alternative and oxidation state-dependent catalytic pathways are employed for specific as well as cascade-like activities simulating natural enzymes as well as biomarkers for the detection of cancerous cells.

Targeting the DNA repair enzymes MTH1 and OGG1 as a novel approach to treat inflammatory diseases.

Autoimmune diseases and acute inflammation like sepsis cause significant morbidity and disability globally, and new targeted therapies are urgently needed. DNA repair and reactive oxygen species (ROS) pathways have long been investigated as targets for cancer treatment, but their role in immunological research has been limited. In this MiniReview, we discuss the DNA repair enzymes MTH1 and OGG1 as targets to treat both T cell‐driven diseases and acute inflammation. The MiniReview is based on a PhD thesis where both enzymes were investigated with cell and animal models. For MTH1, we found that its inhibition selectively kills activated T cells without being toxic to resting cells or other tissues. MTH1 inhibition also had an alleviating role in disease models of psoriasis and multiple sclerosis. We further identified a novel MTH1lowROSlow phenotype among activated T cells. Regarding OGG1, we demonstrated a mechanism of action of the OGG1 inhibitor TH5487, which prevents the assembly of pro‐inflammatory transcription factors and mitigates acute airway infection in mouse models of pneumonia. Hence, we propose both enzymes to be promising novel targets to treat inflammation and suggest that redox and DNA repair pathways could be useful targets for future immunomodulating therapies.

Auranofin attenuates hepatic steatosis and fibrosis in nonalcoholic fatty liver disease via NRF2 and NF- κB signaling pathways.

We aim to evaluate the effects of auranofin, a known antioxidant, on hepatic steatosis, inflammation, and fibrosis, contributing to non-alcoholic steatohepatitis (NASH) development in vivo and in vitro. Transcriptome analysis of LX-2 cells was that expression patterns of genes changed by auranofin, and their related pathways were estimated. We used the gene set enrichment analysis (GSEA) program to determine the pathway involved in overall genetic change. In vitro, LX-2 and HepG2 cells were treated with transforming growth factor (TGF)-β1 and palmitic acid (PA), respectively, and the antifibrotic and antiadipogenic effect function of auranofin was evaluated. Transcriptome analysis revealed that auranofin decreased the expression of 15 genes, including thrombospondin 1, endothelin 1 (ET-1), fibronectin 1, and LOX. The molecular functions of these genes are involved in collagen binding. GSEA of the overall gene expression pattern revealed that many genes increased in the reactive oxygen species pathway and decreased in the inflammatory response. Auranofin decreased nuclear factor kappa B (NF-κB) and IκBα in TGF-β1-induced LX-2 cells, thereby reducing ET-1 and fibrosis. Furthermore, increased pNRF2 in PA-induced HepG2 cells led to increased antioxidant marker expression and decreased lipid accumulation. In the bile duct ligation model mice, auranofin reduced the fibrosis area and increased the survival rate. Auranofin reduced liver fibrosis and lipid accumulation in NASH model mice fed on a Western diet. Auranofin inhibits lipogenesis and fibrosis formation and is a proposed candidate for NASH treatment.

Ferroptosis resistance cooperates with cellular senescence in the overt stage of nonalcoholic fatty liver disease/nonalcoholic steatohepatitis.

Cellular senescence and ferroptosis are the two main, fine-tuned processes in tissue damage restraint; however, they can be overactivated in pathologies such as nonalcoholic fatty liver disease/nonalcoholic steatohepatitis (NAFLD/NASH), becoming dangerous stimuli. Senescence is characterized by a decline in cell division and an abnormal release of reactive oxygen species (ROS), and ferroptosis is represented by iron deposition associated with an excessive accumulation of ROS. ROS and cellular stress pathways are also drivers of NAFLD/NASH development. The etiology of NAFLD/NASH lies in poor diets enriched in fat and sugar. This food regimen leads to liver steatosis, resulting in progressive degeneration of the organ, with a late onset of irreversible fibrosis and cirrhosis. Few studies have investigated the possible connection between senescence and ferroptosis in NAFLD/NASH progression, despite the two events sharing some molecular players. We hypothesized a possible link between senescence and ferroptosis in a NAFLD background. To thoroughly investigate this in the context of “Western-style” diet (WSD) abuse, we used an amylin-modified liver NASH mouse model. The main NASH hallmarks have been confirmed in this model, as well as an increase in apoptosis, and Ki-67 and p53 expression in the liver. Senescent beta-galactosidase-positive cells were elevated, as well as the expression of the related secretory molecules Il-6 and MMP-1. Features of DNA damage and iron-overload were found in the livers of NASH mice. Gpx4 (glutathione peroxidase 4) expression, counteracting ferroptotic cell death, was increased. Notably, an increased number of senescent cells showing overexpression of gpx4 was also found. Our data seem to suggest that senescent cells acquire a gpx4-mediated mechanism of ferroptosis resistance and thus remain in the liver, fostering the deterioration of liver fitness.

Abstract 5663: Clinical relevance of unfolded protein response (UPR) signaling in breast cancer

Abstract Background: Protein homeostasis as regulated by the Endoplasmic Reticulum (ER) is a recognized process involved in cancer progression. ER stress activates the Unfolded Protein Response (UPR) and has been implicated in a variety of cancers. Due to the exposure of chronic stressors, cancer cells learn to adapt to prolonged ER stress by creating pro-survival alterations in the UPR signaling pathway and subsequently drive carcinogenesis. Given the role of the UPR activation in carcinogenesis, we hypothesized that UPR activation could be recognized with pathological progression, mutational accumulation, clinical stage advancement, and survival in breast cancer. Methods: A total of 5,316 breast cancer patients from multiple independent cohorts were analyzed. We defined the UPR pathway score by the degree of enrichment by Gene Set Variant Analysis (GSVA) and median was used to divide high vs low score groups in each cohort. Results: High UPR breast cancer significantly enriched not only cell proliferation-related gene sets (E2F targets, G2M checkpoint, MYC target v1 and v2, and MITOTIC spindle), but also other pro-cancerous gene sets, including MTORC1 signaling, DNA repair, PI3K/AKT/MTOR signaling, and reactive oxygen species pathway, consistently in both METABIC and GSE96058 cohort (all false discovery rate < 0.25). Majority of UPR pathway score high cells in the bulk tumor were tumor cells compared to other cells, including stromal cells, T cells, B cells, and myeloid cells (p < 0.001). UPR score was significantly associated with advanced stage, high grade, and triple negative breast cancer (TNBC) consistently in both cohort (all p < 0.001). High UPR breast cancer was significantly associated with worse patient survival in both cohort (all p < 0.001). Among breast cancer subtype, ER-positive/HER2-negative breast cancer with high UPR was significantly associated with worse survival, but not in HER-positive nor TNBC. High UPR ER-positive/HER2-negative breast cancer was significantly infiltrated with high level of Th1 and Th2 cells, M1 macrophage, and plasma cells consistently in both cohorts (all p < 0.001). On the other hand, high UPR ER-positive/HER2-negative breast cancer was significantly infiltrated with high level of stromal cells, including fibroblasts, adipocytes, and endothelial cells in tumor microenvironment (all p < 0.001). Finally, high UPR metastatic breast cancer was also significantly associated with worse patient survival (p = 0.041). Conclusion: UPR signaling is associated with cancer aggressiveness, and with worse survival in breast cancer, especially ER-positive/HER2-negative breast cancer subtype. Citation Format: Masanori Oshi, Shipra Gandhi, Rongrong Wu, Akimitsu Yamada, Li Yan, Takashi Ishikawa, Itaru Endo, Kazuaki Takabe. Clinical relevance of unfolded protein response (UPR) signaling in breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5663.

Oxidative Stress and Antioxidative Therapy in Pulmonary Arterial Hypertension.

Pulmonary arterial hypertension (PAH) is clinically characterized by a progressive increase in pulmonary artery pressure, followed by right ventricular hypertrophy and subsequently right heart failure. The underlying mechanism of PAH includes endothelial dysfunction and intimal smooth muscle proliferation. Numerous studies have shown that oxidative stress is critical in the pathophysiology of PAH and involves changes in reactive oxygen species (ROS), reactive nitrogen (RNS), and nitric oxide (NO) signaling pathways. Disrupted ROS and NO signaling pathways cause the proliferation of pulmonary arterial endothelial cells (PAECs) and pulmonary vascular smooth muscle cells (PASMCs), resulting in DNA damage, metabolic abnormalities, and vascular remodeling. Antioxidant treatment has become a main area of research for the treatment of PAH. This review mainly introduces oxidative stress in the pathogenesis of PAH and antioxidative therapies and explains why targeting oxidative stress is a valid strategy for PAH treatment.

Physiological and transcription analyses reveal regulatory pathways of 6-benzylaminopurine delaying leaf senescence and maintaining quality in postharvest Chinese flowering cabbage

The regulatory role of cytokinins (CTKs) in leaf senescence has been documented in different species, including Chinese flowering cabbage. However, its physiological and molecular basis relatively remains unknown. In this study, exogenous application of a CTK analogue 6-benzylaminopurine (6-BA) significantly retarded leaf senescence of Chinese flowering cabbage, with less chlorophyll degradation and lower accumulation of reactive oxygen species (ROS) and malondialdehyde compared with the control group. Meanwhile, higher levels of soluble sugars and proteins, flavonoids, cellulose, amino acids, total phenols, procanthocyanins, and vitamin C were retained in 6-BA-treated leaves. 6-BA treatment also prevented the decline in endogenous CTK content and the increase in ethylene, abscisic acid, and jasmonic acid contents. Moreover, the comparative transcriptome analysis revealed that a total of 21,895 differently expressed genes (DEGs) were identified from four comparisons of 6-BA treatment versus the control during senescence. Further analysis showed that most of the identified DEGs were enriched in ROS, respiratory metabolism, and phytohormone pathways, and a total of 50 classes of transcription factors that were possibly involved in modulating these DEGs were obtained. The transcriptional levels of 18 DEGs were verified by Quantitative real-time PCR (qRT-PCR), which confirmed the accuracy of the transcriptomic data. Overall, these findings and data provide a comprehensive view of physiological and molecular events concerning with the CTK-mediated leaf senescence and -maintained quality in economical leafy vegetables.

In vivo and in vitro studies of Alloimperatorin induced autophagy in cervical cancer cells via reactive oxygen species pathway

ABSTRACT Alloimperatorin (Alloi) has been shown to have anti-proliferative effects in our previous studies. we aimed to investigate whether Alloimperatorin induces autophagy through the reactive oxygen species (ROS) pathway and anticancer activity in vivo. The anti-proliferative effect of Alloimperatorin was evaluated using a cell counting kit (CCK-8 kit). Apoptosis was detected using flow cytometry. Confocal microscopy, immunofluorescence, and mRFP-GFP-LC3 lentivirus transfection were used to verify autophagy. Electron microscopy detection of autophagosomes was induced by Alloimperatorin. Western blotting was used to detect autophagy proteins in HeLa and SiHa cells. A xenograft model was used to monitor the inhibitory effect of Alloimperatorin on tumor growth in nude mice. The results showed that Alloimperatorin induced ROS production and inhibited the proliferation of HeLa and SiHa cells. Furthermore, Alloimperatorin increased the apoptosis rate in HeLa and SiHa cells. Confocal microscopy fluorescence indicated that Alloimperatorin increased autophagy fluorescence of HeLa and SiHa cells. mRFP-GFP-LC3 lentivirus transfection and electron microscopy demonstrated that Alloimperatorin increased autophagy in HeLa and SiHa cells. Western blotting showed that Alloimperatorin induced the expression of autophagy proteins in HeLa and SiHa cells. However, N-acetylcysteine reversed the autophagy. These results demonstrate that Alloimperatorin can induce autophagy in HeLa and SiHa cells through the ROS pathway. In vivo xenograft experiments showed that Alloimperatorin could inhibit tumor growth in nude mice. Alloimperatorin is expected to be an effective new drug for cervical cancer treatment. Abbreviations: ROS, reactive oxygen species; Alloi, Alloimperatorin; CCK-8, Cell Counting Kit-8; NAC, N-acetyl-L-cysteine; DCFH-DA, 2,7-dichlorodihydrofluorescein diacetate; OD, optical density; PBS, phosphate buffer solution; BCA, bicinchoninic acid; DAPI, 4,6-diamidino-2-phenylindole; DMSO, dimethyl sulfoxide.

A new water treatment technology—Hybrid ozonation-coagulation process: A review

Hybrid ozonation-coagulation (HOC) process is an integrated water treatment process of simultaneous ozone and coagulation processes. This paper introduces the origin, performance, reaction mechanism and influence of coagulant in HOC system. Compared with traditional air flotation and pre-ozone-coagulation, HOC system shows more advantages in removal of organic pollutants. It is attributed to abundant pathways for reactive oxygen species (ROS) generation in HOC process, which not only transfers pollutants to flocs but also synchronously degrades some organic pollutants.

Abundance of reactive oxygen species (ROS) is associated with tumor aggressiveness, immune response, and worse survival in breast cancer.

Reactive oxygen species (ROS) are oxygen-containing molecules that have high reactivity and play roles in protection or harm the cancer cells. We aimed to clarify the clinical relevance of ROS in breast cancer (BC) tumor microenvironment (TME). We hypothesized that it is associated with worse BC patient outcomes. ROS score was generated by Gene Set Variation Analysis of Hallmark ROS pathway gene set and a total of 6245 BC patients were analyzed. High ROS BC significantly enriched cell proliferation-related gene sets (MYC targets v1 and v2, G2M checkpoint, E2F targets), pro-cancer-related gene sets (DNA repair, unfolded protein response, MTORC1 signaling, PI3K/AKT/MTOR signaling, glycolysis, and oxidative phosphorylation), immune-related gene sets (inflammatory response, allograft rejection, interferon-α and γ responses, complement, and IL6/JAK/STAT3 signaling), and infiltrated immune cells (CD4+ memory and CD8+ T cells, Th1 and Th2, dendritic cells, Tregs, M1 and M2 macrophages) and B cells, as well as elevated cytolytic activity consistently in both METABRIC and GSE96058 cohorts. Cancer cells were the major source of ROS in BC TME of single-cell sequence (GSE75688) cohort. High ROS was associated with intratumor heterogeneity, homologous recombination defects, mutation rates, and neoantigens, and with clinical aggressiveness in AJCC stage, Nottingham grade and Ki67 expression, as well as worse overall survival in both GSE96058 and METABRIC, and with worse disease-specific survival in METABRIC. Abundant ROS in BC patients is associated with abundant mutations, aggressive cancer biology, immune response, and worse survival.

A successful defense of the narrow-leafed lupin against anthracnose involves quick and orchestrated reprogramming of oxidation–reduction, photosynthesis and pathogenesis-related genes

Narrow-leafed lupin (NLL, Lupinus angustifolius L.) is a legume plant cultivated for grain production and soil improvement. Worldwide expansion of NLL as a crop attracted various pathogenic fungi, including Colletotrichum lupini causing a devastating disease, anthracnose. Two alleles conferring improved resistance, Lanr1 and AnMan, were exploited in NLL breeding, however, underlying molecular mechanisms remained unknown. In this study, European NLL germplasm was screened with Lanr1 and AnMan markers. Inoculation tests in controlled environment confirmed effectiveness of both resistance donors. Representative resistant and susceptible lines were subjected to differential gene expression profiling. Resistance to anthracnose was associated with overrepresentation of “GO:0006952 defense response”, “GO:0055114 oxidation–reduction process” and “GO:0015979 photosynthesis” gene ontology terms. Moreover, the Lanr1 (83A:476) line revealed massive transcriptomic reprogramming quickly after inoculation, whereas other lines showed such a response delayed by about 42 h. Defense response was associated with upregulation of TIR-NBS, CC-NBS-LRR and NBS-LRR genes, pathogenesis-related 10 proteins, lipid transfer proteins, glucan endo-1,3-beta-glucosidases, glycine-rich cell wall proteins and genes from reactive oxygen species pathway. Early response of 83A:476, including orchestrated downregulation of photosynthesis-related genes, coincided with the successful defense during fungus biotrophic growth phase, indicating effector-triggered immunity. Mandelup response was delayed and resembled general horizontal resistance.

Aldosterone Suppresses Endothelial Mitochondria through Mineralocorticoid Receptor/Mitochondrial Reactive Oxygen Species Pathway.

Excessive aldosterone secretion causes endothelial dysfunction, vascular inflammation, and vascular fibrosis in patients with primary aldosteronism (PA). Endothelial function is closely related to endothelial mitochondria. However, the effects of elevated aldosterone levels on endothelial mitochondria remain unclear. In this study, we used primary cultured human umbilical vein endothelial cells (HUVECs) to investigate the effects of aldosterone on endothelial mitochondria. Mineralocorticoid receptor (MR) small interfering (si)RNA or glucocorticoid receptor (GR) siRNA were used to confirm the pathway by which aldosterone exerts its effects on the mitochondria of HUVECs. The results showed that excess aldosterone suppressed mitochondrial DNA copy numbers, anti-mitochondrial protein, and SOD2 protein expression in a dose- and time-dependent manner. These effects were attenuated by treatment with MR siRNA, but not with GR siRNA. Furthermore, it was attenuated by treatment with a mitochondria-targeted antioxidant (Mito-TEMPO, associated with mitochondrial reactive oxygen species (ROS) production), but not N-acetyl-L-cysteine (associated with cytosolic ROS production), which suggests that the process was through the mitochondrial ROS pathway, but not the cytosolic ROS pathway. In conclusion, aldosterone excess suppressed endothelial mitochondria through the MR/mitochondrial ROS pathway.

SlSnRK2.3 interacts with SlSUI1 to modulate high temperature tolerance via Abscisic acid (ABA) controlling stomatal movement in tomato

Tomato is often exposed to high temperature stress during summer cultivation. Stomatal movement plays important roles in photosynthesis and transpiration which restricts the quality and yield of tomato under environmental stress. To elucidate the mechanism of stomatal movement in high temperature tolerance, SlSnRK2s (sucrose non-fermenting 1-related protein kinases) silenced plants were generated in tomato with CRISPR-Cas 9 gene editing techniques. Through the observation of stomatal parameters, SlSnRK2.3 regulated stomatal closure which was responded to ABA (abscisic acid) and activated signaling pathway of ROS (reactive oxygen species) in high temperature stress. Based on the positive functions of SlSnRK2.3, the cDNA library was generated to investigate interaction proteins of SlSnRK2s. The interaction between SlSnRK2.3 and SlSUI1 (protein translation factor SUI1 homolog) was employed by Yeast two hybrid assay (Y2H), Luciferase (LUC), and Bimolecular fluorescence complementation (BiFC). Finally, the specific interactive sites between SlSnRK2.3 and SlSUI1 were verified by site-directed mutagenesis. The consistent mechanism of SlSnRK2.3 and SlSUI1 in stomatal movement, indicating that SlSUI1 interacted with SlSnRK2.3 through ABA-dependent signaling pathway in high temperature stress. Our results provided evidence for improving the photosynthetic capacity of tomato under high temperature stress, and support the breeding and genetic engineering of tomato over summer facility cultivation.

Protective Effects of Tiaoganquzhi Decoction in Treating inflammatory Injury of Nonalcoholic Fatty liver Disease by Promoting CGI-58 and Inhibiting Expression of NLRP3 Inflammasome.

Tiaoganquzhi Decoction (TGQZD) is a traditional Chinese herbal formulation demonstrated to be a clinically effective treatment for nonalcoholic fatty liver disease (NAFLD), although details concerning its clinical mechanism are poor. This study aimed to explore the mechanism of TGQZD on improvement of inflammatory damage and dyslipidemia caused by NAFLD through the CGI-58/ROS/NLRP3 inflammasome pathway. In our research, the in vivo protective effects of TGQZD on HFD-induced liver injury in rats and in vitro using lipopolysaccharide (LPS)+palmitate (PA)-stimulated HepG-2 cells model. Histological changes were evaluated by hematoxylin-eosin and Oil Red O staining. Inflammatory cytokines and protein expression were analyzed by ELISA, Real time PCR and western blotting. Liver function, blood lipids, free fatty acids (FFA), and reactive oxygen species (ROS) were determined by biochemical detection. Our results indicated that TGQZD exhibited anti-inflammatory activity, reduced the severity of NAFLD and ameliorated the pathological changes. Further, TGQZD improved liver function and lipid metabolism in NAFLD rats. TGQZD lowered serum aspartate aminotransferase, alanine aminotransferase, triglyceride, and total cholesterol levels. TGQZD suppressed the formulation of FFA and ROS. It also reduced the expression and release of the inflammatory cytokine interleukin-1β by promoting CGI-58 expression and inhibiting the expression of FFA, TNF-α, and the NLRP3 inflammasome induced by ROS. TGQZD exhibited anti-inflammatory effects via the CGI-58, ROS and NLRP3 inflammasome pathway in vivo and in vitro, respectively. Our findings demonstrated that TGQZD is a useful and effective therapeutic agent for treating NAFLD via promotion of CGI-58 to inhibit the expression of ROS-induced NLRP3 inflammasome.

Protein Kinase C Involvement in Neuroprotective Effects of Thymol and Carvacrol Against Toxicity Induced by Amyloid-β in Rat Hippocampal Neurons.

We have reported that thymol and carvacrol can improve cognitive abilities in Alzheimer Disease (AD) rat models. However, the mechanism of their action is not yet fully understood. Recently, our in vitro results suggested that PC12 cell death induced by Aβ25-35 can be protected by thymol and carvacrol via Protein Kinase C (PKC) and Reactive Oxygen Species (ROS) pathways. So, we hypothesize that the mechanisms of thymol and carvacrol in improving the learning impairment in the AD rat model may be related to their effects on PKC. So, the activity of PKC and protein expression levels of PKCα were examined in the hippocampal cells of the AD rat model. To examine the thymol and carvacrol effects, we performed a behavioral test in AD rat models induced by Aβ25-35 neurotoxicity. To access the underlying mechanism of the protective effects, western blotting was performed with antibodies against PKCα. We also measured the PKC activity assay by Elisa. Histopathological studies were carried out in the hippocampus with Hematoxylin and Eosin (H&E) staining. The escape latency increased in Aβ-received rats compared to the control group, and thymol and carvacrol reversed this deficit. Furthermore, these compounds could enhance the PKC activity and increase the PKCα expression ratio. Moreover, H&E staining showed that Aβ caused shrinkage of the CA1 pyramidal neurons. However, thymol and carvacrol treatments could prevent this effect of Aβ peptides. This study suggests that Amyloid-Beta (Aβ) results in memory decline and histochemical disturbances in the hippocampus. Moreover, these results revealed that thymol and carvacrol could have protective effects on cognition in AD-like models via PKC activation. Rat's ability to find the invisible platform in the Morris Water Maze (MWM) was impaired by Amyloid-Beta (Aβ) infusion in the hippocampus, while this effect was reversed by thymol or carvacrol administration.Aβ significantly downregulated the Protein Kinase C (PKC) activity in rats' hippocampus.Western blot analysis demonstrated that Aβ significantly reduced PKCα protein expression in AD rat model hippocampal cells.The expression ratio of PKCα was upregulated following the injection of thymol and carvacrol in rats.Injection of Aβ in the hippocampus resulted in histochemical disturbances in CA1 pyramidal neurons.Carvacrol and thymol can prevent several histological changes induced by Aβ. Alzheimer's disease is one of the most important brain diseases in which the learning and memory are impaired. One of the main causes of Alzheimer's disease is the presence of amyloid beta plaques in the neurons. Protein kinase C enzyme reduces amyloid production and accumulation in the brain. In the present study, we tested the possible effects of carvacrol and thymol in a rat model of Alzheimer's disease. Memory impairment was induced in adult rats by intra-cerebral infusion of amyloid β. One week later, the memory-impaired animals were treated with carvacrol and thymol. Finally, we tested their memory in a Morris water maze apparatus. Furthermore, their hippocampus was dissected and PKC activity and the neuronal injury was evaluated. Our findings exhibited that thymol and carvacrol improved rats' memory performance. In addition, thymol and carvacrol significantly increased PKC activity and prevented neuronal cell loss in the rat hippocampus. This study shows that thymol and carvacrol have beneficial effects on memory and cognitive function via PKC activation.

Perfluorooctanoic acid exposure increases both proliferation and apoptosis of human placental trophoblast cells mediated by ER stress-induced ROS or UPR pathways

Perfluorooctanoate acid (PFOA) is a highly persistent and widespread chemical in the environment. PFOA serum levels in pregnant women are positively associated with an increased risk of placenta-related disorders. However, the mechanism of PFOA cytotoxicity involved in placental cells and cellular responses such as ER stress remains poorly understood. In this study, we studied the cellular toxicity of PFOA with a focus on proliferation and apoptosis in a human placental trophoblast cell line. Cell viability, number, apoptosis, stress response, activation of the involved signaling pathways were assessed. Our results showed PFOA affected cell viability, proliferation and also resulted in apoptosis. Besides, both pro-proliferation and pro-apoptosis effects were attenuated by endoplasmic reticulum (ER) stress inhibitors. Further experiments demonstrated that two different signaling pathways were activated by PFOA-induced ER stress and involved in PFOA toxicity: the reactive oxygen species (ROS)-dependent ERK signaling triggered trophoblast proliferation, while the ATF4-dependent C/EBP homologous protein (CHOP) signaling was the trigger of apoptosis. We conclude that PFOA-induced ER stress is the trigger of proliferation and apoptosis of trophoblast via ROS or UPR signaling pathway, which leads to the altered balance critical to the normal development and function of the placenta.