Increase In ROS Research Articles

Unraveling the mechanism of quercetin alleviating perfluorooctane sulfonate-induced apoptosis in grass carp (Ctenopharyngodon idellus) hepatocytes: AMPK/mTOR-mediated mitophagy

Exposure to persistent new organic pollutants in the environment often leads to high mortality and causes serious economic losses to the aquaculture industry. Currently, perfluorooctane sulfonate (PFOS) is persistent and bio-accumulative in the environment, causing potential risks to aquatic ecosystems, but its toxicity mechanism to aquatic organisms is still unclear. As a natural flavonoid compound, quercetin (QU) has many biological activities such as anti-oxidation, anti-inflammatory, anti-apoptosis and immune regulation. Whether it can be used as a candidate medicine to alleviate PFOS toxicity needs to be further explored. Therefore, in this study, we treated (Ctenopharyngodon idellus) grass carp hepatocytes (L8824) with PFOS (200 μM) and/or QU (60 μM) for 24 h. The results showed that PFOS significantly increased the release of LDH and active oxygen (ROS) in L8824 cells, and led to the decrease of mitochondrial membrane potential (ΔΨm) and ATP content, the increase of mitochondrial ROS, the disorder of mitochondrial dynamics, and the initiation of Bcl-2/Bax-mediated apoptosis. Surprisingly, QU can alleviate the above PFOS-induced grass carp hepatocyte toxicity. In addition, in order to further explore the protective mechanism of QU, we used the molecular docking to predict the binding site between QU and AMPK, and found that there was a high binding capacity between QU and AMPK. In addition, we used Compound C (CC) and 3-Methyladenine (3-MA) to intervene. The results showed that CC and 3-MA intervention aggravated mitochondrial dysfunction and apoptosis factor expression in the QU+PFOS group. These data indicate that PFOS induces oxidative stress, mitochondrial dysfunction, and apoptosis. The regulation of AMPK/mTOR mediated mitophagy by QU may be a new therapeutic strategy to alleviate the hepatotoxicity of PFOS grass carp. This study provides theoretical basis and reference for exploring the toxic mechanism and biological toxic effects of PFOS, and provides a scheme for improving the economic benefits of aquaculture.

ERK1/2 Inhibition Overcomes Resistance to Venetoclax in AML By Inhibiting Drp1 Dependent Mitochondrial Fission

Background: Primary or secondary resistance to venetoclax is frequently associated with mutational/non-mutational activation of MAPK pathways. ERK1/2 are terminal kinases in MAPK pathway and may be an appropriate target regardless of the upstream mechanisms that activate the pathway. ERK1/2 mediated phosphorylation of Drp1 promotes mitochondrial fission and MAPK-driven tumor growth in RAS driven solid cancers (Kashatus et al., Mol Cell. 2015). However, the role of Drp1 dependent mitochondrial dynamics in therapeutic resistance in AML is unexplored. Methods: ERK1/2 was inhibited using Compound 27 (ERKi, Heightman et al., J Med Chem. 2018), an analog of ASTX029 (Munck et al., Mol Cancer Ther. 2021) in vitro and using ASTX029 in vivo. Preclinical models of venetoclax resistance and primary patient samples (n=8) were used to assess the synergy of concomitant Bcl2 and ERK1/2 inhibition (ERKi). In addition, a comprehensive analysis of alteration of signaling pathways, apoptotic signatures and DNA damage responses in response to ERKi+/-venetoclax were analyzed by mass cytometry based proteomic analysis (CyTOF) and immunoblotting. The potential clinical relevance of ERK1/2 inhibition to overcome venetoclax resistance was confirmed in a PDX model of AML (established from an AML patient who relapsed after venetoclax/decitabine treatment). Mitochondrial images were acquired using super-resolution imaging with OMX-Blaze followed by quantification with Imaris. Results : We previously reported the synergy of ERK1/2 inhibition using Compound 27 with venetoclax at inducing apoptosis in RAS mutated and/or venetoclax resistant AML cells including venetoclax resistant isogenic lines (Sharma et al., Blood 140; Supplement 1, 2022). Venetoclax+ERKi depleted leukemia progenitor cells in primary AML samples (CI:0.03-0.23) and impaired clonogenic growth of NRAS mutant PDX cells. In a PDX mouse model of post venetoclax/decitabine-relapsed AML, ASTX029+venetoclax treatment improved survival compared to vehicle (median survival 76.5 days vs. 50 days, p=0.0006) and venetoclax alone (median survival 76.5 days vs. 51.5 days, p=0.0065) (Figure 1) with corresponding reduction in leukemia burden in bone marrow (p<0.0001) and spleen (p<0.0001). CyTOF analysis using PDX bone marrow showed decreased expression of Mcl-1 and pMcl-1-T163 and an increased expression of BIM in response to ERKi+/-venetoclax (Figure 1). To maintain stemness in AML, mitochondrial ROS mitigation and Drp1-mediated mitochondrial fission are crucial (Schimmer et al., Cell Stem Cell. 2018). The inhibition of ERK1/2 resulted in decreased pDrp1-Ser616, along with an increase in mitochondrial length (p<0.001) suggesting impaired mitochondrial fission. This was accompanied by a decrease in mitochondrial membrane potential (p<0.0001) and an increase in mitochondrial ROS (p<0.0001). Overexpression (OE) of a phospho-mimetic i.e. Drp1-Ser616Glu-Ser637Ala led to shorter mitochondrial length (Figure 2), suggesting enhanced fission, a distinct metabolic phenotype with decreased ROS production and decreased mitochondrial depolarization with venetoclax+/- ERKi. Finally, Drp1 phospho-mimetic OE reversed apoptosis induction by venetoclax +/- ERKi (Figure 2) as compared to the wild-type and phospho-null (Ser616Ala) Drp1 (p<0.001) expressing cells, supporting the role of mitochondrial fission in resistance to venetoclax. Conclusion: The increased mitochondrial fission driven by ERK1/2 mediated phosphorylation of Drp1 contributes to venetoclax resistance in AML and inhibiting ERK1/2/Drp1 axis overcomes resistance to venetoclax by inhibiting mitochondrial fission (Figure 2). These data provide a strong rationale for the combination of ERK1/2 and Bcl-2 inhibitors in the treatment of AML.

Metabolic Stress of Red Blood Cells Induces Hemoglobin Glutathionylation

Metabolic stress caused by a lack of glucose significantly affects the state of red blood cells, where glycolysis is the main pathway for the production of ATP. Hypoglycemia can be both physiological (occurring during fasting and heavy physical exertion) and pathological (accompanying a number of diseases, such as diabetes mellitus). In this study, we have characterized the state of isolated erythrocytes under metabolic stress caused by the absence of glucose. It was established that 24 h of incubation of the erythrocytes in a glucose-free medium simulating blood plasma led to a twofold decrease in the ATP level into them. Besides, the cell sizes as well as intracellular sodium concentration were increased. These findings could be the result of a disruption in ion transporters` functioning because of a decrease in the ATP level. The calcium level remained unchanged. With a lack of glucose in the medium of isolated erythrocytes, there was no increase in ROS and significant change in the level of nitric oxide, while the level of the main low-molecular weight thiol of cells, glutathione (GSH), decreased by almost 2 times. It was found that the metabolic stress of isolated red blood cells induced hemoglobin glutathionylation despite the absence of ROS growth. The reason was the lack of ATP, which led to a decrease in the level of GSH because of the inhibition of its synthesis and probably, by decrease in the NADPH level required for glutathione (GSSG) reduction and protein deglutathionylation. Thus, erythrocyte metabolic stress induced hemoglobin glutathionylation, which is not associated with an increase in ROS. This may have an important physiological significance, since glutathionylation of hemoglobin changes its affinity for oxygen.

Low concentrations of antimony impair adipogenesis and endoplasmic reticulum homeostasis during 3T3-L1 cells differentiation

Antimony (Sb) is a metalloid widely present in plastics used for food contact packaging, toys and other household items. Since Sb can be released by these plastics and come into contact with humans, health concerns have been highlighted. The effect of Sb on human tissues is yet controversial, and biochemical mechanisms of toxicity are lacking. In the present study, the effect of very low nanomolar concentrations of Sb(III), able to mimicking chronic human exposure, was evaluated in 3T3-L1 murine cells during the differentiation process. Low nanomolar Sb exposure (from 0.05 to 5 nM) induced lipid accumulation and a marked increase in C/EBP-β and PPAR-γ levels, the master regulators of adipogenesis. The Sb-induced PPAR-γ was reverted by the estrogen receptor antagonist ICI 182,780. Additionally, Sb stimulated preadipocytes proliferation inducing G2/M phase of cell cycle and this effect was associated to reduced cell-cycle inhibitor p21 levels. In addition to these metabolic dysfunctions, Sb activated the proinflammatory NF-κB pathway and altered endoplasmic reticulum (ER) homeostasis inducing ROS increase, ER stress markers XBP-1s and pEIF2a and downstream genes, such as Grp78 and CHOP. This study, for the first time, supports obesogenic effects of low concentrations exposure of Sb during preadipocytes differentiation.

Fenpropathrin induces neurotoxic effects in common carp (Cyprinus carpio L.)

Fenpropathrin (FEN) is a synthetic pyrethroid that has been frequently detected in aquatic environments, yet the neurotoxic impacts and underlying mechanisms on nontarget organisms are lacking. In this experiment, common carp were exposed to 0.45 and 1.35 μg/L FEN for 14 d and exhibited abnormal locomotor behaviour. Biochemical and molecular analysis results indicated that FEN altered the contents of tight junction proteins (claudin-1, occludin, and ZO-1), disturbed Na+-K+-ATPase and AChE activities, caused abnormal expression of neurotransmitters (ACh, DA, GABA, 5-HT, and glutamate) and caused histological damage in the brain, suggesting that FEN may damage the blood–brain barrier and induce neurotoxicity in carp. Furthermore, FEN also promoted an increase in ROS, changed SOD and CAT activities, and generally upregulated the contents of MDA, 8-OHdG, and protein carbonyl in the brain, indicating that FEN can induce oxidative stress and cause damage to lipids, DNA, and proteins. Moreover, inflammation-related indicators (TNF-α, IL-1β, IL-6, and IL-10), mitophagy-related genes (PINK1, parkin, ulk1, beclin1, LC3, p62, tfeb, and atg5), and apoptosis-related parameters (p53, bax, bcl-2, caspase-3, caspase-8, and caspase-9) were also significantly changed, suggesting that inflammation, mitophagy, and apoptosis may participate in FEN-induced neurotoxicity in carp. This study refines the understanding of the toxicity mechanism of FEN and thus provides data support for the risk assessment of FEN.

Interpretation of the anti-influenza active ingredients and potential mechanisms of Ge Gen Decoction based on spectrum-effect relationships and network analysis

Ethnopharmacological relevanceGe Gen Decoction (GGD) is a classic traditional Chinese medicine (TCM) prescription that originated in the ancient Chinese medical book “Treatise on Febrile Diseases”. The prescription consists of 7 herbs: Pueraria lobata (Willd.) Ohwi, Ephedra sinica Stapf, Cinnamomum cassia (L.) J.Presl, Paeonia lactiflora Pall., Glycyrrhiza uralensis Fisch., Zingiber officinale Rosc., and Ziziphus jujuba Mill. It can alleviate high fever and soreness in the neck and shoulders caused by exogenous wind chill and is widely used in both China and Japan. Currently, GGD is primarily utilized for treating flu and the common cold. GGD has been reported to show significant anti-influenza A virus (IAV) activity both in vitro and in vivo. However, the active ingredients responsible for its anti-influenza properties have not been elucidated, and the mechanisms underlying its anti-influenza effects require further research. Aim of the studyThis study aims to investigate the active ingredients and molecular mechanisms of GGD in treating influenza. Materials and methodsHPLC chromatograms were established for GGD water and different polar extracts. The effect of different GGD extracts on pulmonary virus titers and TNFα expression was assessed through RT-PCR analysis. Spectrum-effect relationships between chromatographic peaks of GGD and its virus inhibition rate and TNFα inhibition rate were investigated using partial least squares regression (PLSR) analysis. HPLC-Q-TOF-MS was utilized to identify the constituents absorbed into the blood after oral administration of GGD. Network analysis of the absorbed forms of active ingredients was conducted to predict the potential mechanisms of GGD. Subsequently, total SOD activity, CAT and HO-1 expression and Nrf2 nuclear translocation were then analyzed. Finally, the impact of interfering with HO-1 expression on the anti-IAV activity of GGD was examined. ResultsThe study identified 11 anti-influenza active ingredients in GGD, which are daidzein, ononin, genistin, daidzin, 3′-methoxypuerarin, puerarin, pseudoephedrine, paeoniflorin, pormononetin-7-xylosyl-glucoside, penistein-7-O-apiosyl-glucoside, and ephedrine. Network analysis revealed various biological activities of GGD, including responses to ROS and oxidative stress. GGD also involves multiple antiviral pathways, such as hepatitis B, IAV, and Toll-like receptor pathways. Experimental assays demonstrated that GGD possesses independent antioxidant activity both in vitro and in vivo. In vitro, GGD inhibits the increase in intracellular ROS induced by IAV. In vivo, it reduces MDA levels and increases total pulmonary SOD activity. Applying siRNA and flow cytometry analysis revealed that GGD alleviates IAV-induced oxidative burst by promoting the expression of HO-1 and CAT. Western blot analysis revealed that GGD effectively promotes Nrf2 nuclear translocation and enhances Nrf2 expression. Furthermore, this study found that the enhancement of HO-1 expression by GGD contributed to its anti-IAV activity. ConclusionsThe study identified the active ingredients of GGD against influenza and demonstrated the beneficial role of GGD's antioxidant activity in treating flu. The antioxidant activity of GGD is associated with the promotion of Nrf2 nuclear translocation and the upregulation of antioxidant enzymes such as SOD, HO-1, and CAT. Overall, this study provides evidence supporting the use of GGD as an adjunctive or complementary therapy for influenza.

3D-Shaped Binders of Unfolded Proteins Inducing Cancer Cell-Specific Endoplasmic Reticulum Stress In Vitro and In Vivo.

The amount of unfolded proteins is increased in cancer cells, leading to endoplasmic reticulum (ER) stress. Therefore, cancer cells are sensitive to drugs capable of further enhancing ER stress. Examples of such drugs include the clinically approved proteosome inhibitors bortezomib and carfilzomib. Unfortunately, the known ER stress inducers exhibit dose-limiting side effects that justify the search for better, more cancer-specific drugs of this type. Herein, we report on FeC 2, which binds to unfolded proteins prevents their further processing, thereby leading to ER stress and ROS increase in cancer cells, but not in normal cells. FeC 2 exhibits low micromolar toxicity toward human acute promyelocytic leukemia HL-60, Burkitt's lymphoma BL-2, T-cell leukemia Jurkat, ovarian carcinoma A2780, lung cancer SK-MES-1, and murine lung cancer LLC1 cells. Due to the cancer-specific mode of action, 2 is not toxic in vivo up to the dose of 147 mg/kg, does not affect normal blood and bone marrow cells at the therapeutically active dose, but strongly suppresses both primary tumor growth (confirmed in Nemeth-Kellner lymphoma and LLC1 lung cancer models of murine tumor) and spreading of metastases (LLC1).

Response Profiles of BV2 Microglia to IFN-γ and LPS Co-Stimulation and Priming.

(1) Background: The latest research illustrates that microglia phenotype is not the binary 'resting' and 'activated' profiles. Instead, there is wide diversity in microglia states. Similarly, when testing different stimulation protocols for BV2 microglia, we discovered differences in the response of the cells in terms of the production of intracellular ROS (iROS), nitric oxide (NO), CD40 expression, and migratory capacity. (2) Methods: BV2 microglia were treated with single interferon gamma (IFN-γ) stimulation, LPS/IFN-γ co-stimulation, and priming with IFN-γ followed by stimulation with LPS for 24 h. The responses of BV2 microglia were then assessed using the H2DCFDA test for iROS, the Griess assay for NO, immunophenotyping for CD40/CD11b/MHC II, and migration using a transwell apparatus. (3) Results: Single stimulation with IFN-γ induced NO but not ROS in BV2 microglia. Co-stimulation with LPS200IFN-γ2.5 induced a higher iROS production (a 9.2-fold increase) and CD40 expression (28031 ± 8810.2 MFI), compared to priming with primedIFN-γ50LPS100 (a 4.0-fold increase in ROS and 16764 ± 1210.8 MFI of CD40). Co-stimulation also induced cell migration. On the other hand, priming BV2 microglia (primedIFN-γ50LPS100) resulted in a higher NO production (64 ± 1.4 µM) compared to LPS200IFN-γ2.5 co-stimulation (44 ± 1.7 µM). Unexpectedly, priming inhibited BV2 migration. (4) Conclusions: Taken together, the findings from this project reveal the ability of co-stimulation and priming in stimulating microglia into an inflammatory phenotype, and the heterogeneity of microglia responses towards different stimulating approaches.

Hepatitis C virus alters the morphology and function of peroxisomes.

Despite the introduction of effective treatments for hepatitis C in clinics, issues remain regarding the liver disease induced by chronic hepatitis C virus (HCV) infection. HCV is known to disturb the metabolism of infected cells, especially lipid metabolism and redox balance, but the mechanisms leading to HCV-induced pathogenesis are still poorly understood. In an APEX2-based proximity biotinylation screen, we identified ACBD5, a peroxisome membrane protein, as located in the vicinity of HCV replication complexes. Confocal microscopy confirmed the relocation of peroxisomes near HCV replication complexes and indicated that their morphology and number are altered in approximately 30% of infected Huh-7 cells. Peroxisomes are small versatile organelles involved among other functions in lipid metabolism and ROS regulation. To determine their importance in the HCV life cycle, we generated Huh-7 cells devoid of peroxisomes by inactivating the PEX5 and PEX3 genes using CRISPR/Cas9 and found that the absence of peroxisomes had no impact on replication kinetics or infectious titers of HCV strains JFH1 and DBN3a. The impact of HCV on peroxisomal functions was assessed using sub-genomic replicons. An increase of ROS was measured in peroxisomes of replicon-containing cells, correlated with a significant decrease of catalase activity with the DBN3a strain. In contrast, HCV replication had little to no impact on cytoplasmic and mitochondrial ROS, suggesting that the redox balance of peroxisomes is specifically impaired in cells replicating HCV. Our study provides evidence that peroxisome function and morphology are altered in HCV-infected cells.

SOX4 as a potential therapeutic target for pathological cardiac hypertrophy

Pathological cardiac hypertrophy can lead to heart failure, making its prevention crucial. SOX4, a SOX transcription factor, regulates tissue growth and development, although its role in pathological cardiac hypertrophy is unclear. We found that the SOX4 expression was elevated in hypertrophic hearts and angiotensin II (Ang II)-treated neonatal rat cardiomyocytes (NRCMs), and knocking down the SOX4 expression in NRCMs and mouse hearts significantly reduced the hypertrophic response. Mechanistically, SOX4 can bind to the SIRT3 promoter, inhibit SIRT3 transcription and expression, and thus affect downstream MnSOD acetylation levels, leading to abnormal increases in ROS and oxidative stress levels and promoting the occurrence of cardiac hypertrophy. In conclusion, this study identified a new role for SOX4 in regulating cardiac hypertrophy, and decreasing SOX4 expression may be a potential treatment for pathological cardiac hypertrophy.

Combined Effects of Fluoride and Dietary Seleno-L-methionine at Environmentally Relevant Concentrations on Female Zebrafish (Danio rerio) Liver: Histopathological Damages, Oxidative Stress and Inflammation.

Fluoride, a global environmental pollutant, is ubiquitous in aquatic environments and coexists with selenium, which can cause complex effects on exposed organisms. However, data on the interaction of fluoride and selenium remain scarce. In this study, female zebrafish (Danio rerio) were exposed to fluoride (80 mg/L sodium fluoride) and/or dietary selenomethionine for 30, 60 and 90 days, the effects on the liver of zebrafish were investigated. The results indicated that an increase in fluoride burden, inhibited growth and impaired liver morphology were recorded after fluoride exposure. Furthermore, fluoride alone caused oxidative stress and inflammation in the liver, as reflected by the increase in ROS and MDA contents, the reduction of anti-oxidative enzymes, the altered immune related enzymes (ACP, AKP, LZM and MPO) and the expression of IL-6, IL-1β, TNF-α, IL-10 and TGF-β. In contrast, co-exposure to fluoride and Se-Met decreased fluoride burden and restored growth. Furthermore, dietary Se-Met alleviated oxidative stress, inflammation and impaired morphology in liver trigger by fluoride. However, dietary Se-Met alone increased the activities of SOD and CAT. These results demonstrate that the protective effect of dietary Se-Met against chronic fluoride toxicity at a certain level.

Combined Effects of Fluoride and Dietary Seleno-L-Methionine at Environmentally Relevant Concentrations on Female Zebrafish (Danio rerio) Liver: Histopathological Damages, Oxidative Stress and Inflammation.

Fluoride, a global environmental pollutant, is ubiquitous in aquatic environments and coexists with selenium, which can cause complex effects on exposed organisms. However, data on the interaction of fluoride and selenium remain scarce. In this study, female zebrafish (Danio rerio) were exposed to fluoride (80mg/L sodium fluoride) and/or dietary selenomethionine(Se-Met) for 30, 60 and 90days, the effects on the liver of zebrafish were investigated. The results indicated that an increase in fluoride burden, inhibited growth and impaired liver morphology were recorded after fluoride exposure. Furthermore, fluoride alone caused oxidative stress and inflammation in the liver, as reflected by the increase in ROS and MDA contents, the reduction of anti-oxidative enzymes, the altered immune related enzymes (ACP, AKP, LZM and MPO) and the expression of IL-6, IL-1β, TNF-α, IL-10 and TGF-β. In contrast, co-exposure to fluoride and Se-Met decreased fluoride burden and restored growth. Furthermore, dietary Se-Met alleviated oxidative stress, inflammation and impaired morphology in liver trigger by fluoride. However, dietary Se-Met alone increased the activities of SOD and CAT. These results demonstrate that the protective effect of dietary Se-Met against chronic fluoride toxicity at a certain level.

Programmed Cell Death Protein 2-like Promotes Inflammation and Oxidative Stress in Vascular Endothelial Cells.

Programmed cell death protein 2-like (PDCD2L) is a shuttle protein of the nucleus and cytoplasm and is related to the ribosome biogenesis. However, there are few reports on the relationship between PDCD2L and inflammation, and the exact relationship between PDCD2L and inflammation has not been determined in vascular endothelial cells yet. Accordingly, we focus on exploring the relationship between PDCD2L and inflammation and its potential mechanisms. Our research findings suggested that PDCD2L is a proinflammatory target. The result showed that, by interfering with the expression of PDCD2L, LPS-induced inflammation of vascular endothelial cells can be reduced, such as IL-6 and IL-1β, as well as the adhesion factor ICAM1. Meanwhile, overexpression of PDCD2L can further increase LPS-induced inflammation levels, ICAM1, and ROS production, reduce CAT, GSH/GSSG levels, and increase SOD levels. Therefore, we determined that PDCD2L has a regulatory effect on inflammation and oxidative stress of vascular endothelial cells, and its regulatory mechanism may be related to inflammatory transcription factors STAT1, NF-κB regulation, transport of inflammatory messenger mRNA, and ribosome biogenesis. Then, we screened that andrographolide (Andro) can bind to PDCD2L, thus inhibiting inflammation and endothelial cell adhesion caused by the overexpression of PDCD2L. This study reveals that PDCD2L is a potential anti-inflammatory therapeutic target, providing new exploration for the development of anti-inflammatory drugs.

Biosensor-integrated transposon mutagenesis reveals rv0158 as a coordinator of redox homeostasis in Mycobacterium tuberculosis.

Mycobacterium tuberculosis (Mtb) is evolutionarily equipped to resist exogenous reactive oxygen species (ROS) but shows vulnerability to an increase in endogenous ROS (eROS). Since eROS is an unavoidable consequence of aerobic metabolism, understanding how Mtb manages eROS levels is essential yet needs to be characterized. By combining the Mrx1-roGFP2 redox biosensor with transposon mutagenesis, we identified 368 genes (redoxosome) responsible for maintaining homeostatic levels of eROS in Mtb. Integrating redoxosome with a global network of transcriptional regulators revealed a hypothetical protein (Rv0158) as a critical node managing eROS in Mtb. Disruption of rv0158 (rv0158 KO) impaired growth, redox balance, respiration, and metabolism of Mtb on glucose but not on fatty acids. Importantly, rv0158 KO exhibited enhanced growth on propionate, and the Rv0158 protein directly binds to methylmalonyl-CoA, a key intermediate in propionate catabolism. Metabolite profiling, ChIP-Seq, and gene-expression analyses indicate that Rv0158 manages metabolic neutralization of propionate toxicity by regulating the methylcitrate cycle. Disruption of rv0158 enhanced the sensitivity of Mtb to oxidative stress, nitric oxide, and anti-TB drugs. Lastly, rv0158 KO showed poor survival in macrophages and persistence defect in mice. Our results suggest that Rv0158 is a metabolic integrator for carbon metabolism and redox balance in Mtb.

VDAC1 participates in house dust mite-induced asthmatic airway inflammation in mice by inducing ferroptosis of airway epithelial cells

To investigate the role of voltage-dependent anion-selective channel protein 1 (VDAC1) in house dust mite (HDM)-induced asthmatic airway inflammation and its mechanism for regulating ferroptosis in airway epithelial cells. Human airway epithelial (HBE) cells were exposed to a concentration gradient (200, 400 and 800 U) of HDM alone or in combination with treatment with 10 μmol/L VBIT-4 (a VDAC1 inhibitor) for 24 h, and the expressions of VDAC1 and ferroptosis-associated proteins in the cells were examined. Adult male BALB/c mice were treated with intranasal instillation of VBIT-4, HDM, or both, and the level of airway inflammation and the expressions of ferroptosis-associated proteins were detected with immunohistochemistry. In HBE cells, HDM exposure caused a significant increase of mitochondrial ROS (mtROS) production and obviously decreased the mitochondrial membrane potential. The exposed cells showed obviously increased protein expressions of VDAC1 (P=0.005) and FTH1 (P=0.030) but decreased protein expression of GPX4 (P=0.015) and FTH1 (P=0.037), while the treatment with VBIT-4 repressed the expression of GPX4 (P=0.001) and inhibited the expression of VDAC1. In BALB/c mice, treatment with VBIT-4 significantly improved HDM-induced airway inflammation by reducing the number of inflammatory cells (P=0.029) in the airway and the number of eosinophils in the alveolar lavage fluid. Immunohistochemical staining showed that GPX4 expression in the airway epithelial cells was significantly increased after treatment with VBIT-4. VDAC1 participates in HDM-induced chronic airway inflammation in bronchial asthma by causing ferroptosis of the airway epithelial cells.

Curcumin suppresses proliferation, migration and invasion of papillary thyriod cancer B-CPAP cells through the Keap1-Nrf2 pathway

To observe the effects of curcumin on migration and invasion of papillary thyriod cancer B-CPAP cells. B-CPAP cells were treated with 5, 10, 15, or 20 μmol/L curcumin, and the changes in cell survival, migration and invasion were examined using MTT assay and Transwell assay. ROS levels in the treated cells were detected with a DCFH-DA probe. The expression levels of Nrf2 and Keap1 in the cells were determined using Western blotting and qRT-PCR. Treatment with curcumin dose- and time-dependently suppressed the viability of B-CPAP cells (P < 0.05 or P < 0.01). Curcumin inhibited the migration and invasion (P < 0.001) and promoted ROS production in B-CPAP cells in a dose-dependent manner, and application of NAC effectively reversed curcumin- induced increase of ROS. Curcumin at 20 μmol/L significantly decreased the protein and mRNA expressions of Nrf2 and increased the expressions of Keap1 protein and mRNA (P < 0.05 or P < 0.01), causing also significantly reduced expression of Nrf2 protein in the cell nuclei (P < 0.05) without obviously affecting its expression in the cytoplasm (P > 0.05). Curcumin inhibits the proliferation, migration and invasion of papillary thyriod cancer B-CPAP cells probably via the Keap1-Nrf2 signaling pathway.

Dyslipidemia initiates keratinocytes proliferation through upregulation of lncRNA NEAT in psoriasis patients

BackgroundPsoriasis is a chronic inflammatory immune-mediated and hyper proliferative skin disorder that has underlying genetic factors. Psoriasis can result from interaction of cytokines between keratinocytes and T-lymphocytes. NEAT is a lncRNA involved in immune modulation and has been previously studied in cancers. This study aims to clarify the unprecedented role of NEAT in psoriasis pathogenesis.MethodsThe study was conducted on 50 healthy control subjects and 50 psoriasis patients. Blood samples from all participants were collected for analysis of their lipid profile. qRT-PCR was done for lncRNA NEAT, TNF-α, VEGF genes expression. The levels of ROS and caspase-3 were estimated by ELISA. ROC analysis was done to detect the diagnostic value of lncRNA NEAT gene expression.ResultsDyslipidemia is more prevalent among psoriasis patients. A significant up regulation in lncRNA NEAT, TNF-α, VEGF genes expression (p value˂0.001) in psoriasis patients in addition to significant increase in ROS and caspase-3 levels (p value˂0.001) in compare to controls. Additionally, a positive significant correlation between TNF-α, ROS, NEAT, caspase-3 and dyslipidemia. NEAT had an area under the curve (AUC) of 0.931 (95% CI 0.844–0.978, p < 0.001).ConclusionDyslipidemia is an initiating signal in psoriasis pathogenesis that creates a state of chronic inflammation and oxidative stress. This state induces keratinocytes proliferation and release of NEAT with subsequent caspase-3 activation to counteract the proliferating cells. NEAT could be considered as a good diagnostic biomarker for psoriasis.Graphical abstract

The Mechanisms of Ferroptosis Under Hypoxia.

Ferroptosis is a new form of programmed cell death, which is characterized by the iron-dependent accumulation of lipid peroxidation and increase of ROS, resulting in oxidative stress and cell death. Iron, lipid, and multiple signaling pathways precisely control the occurrence and implementation of ferroptosis. The pathways mainly include Nrf2/HO-1 signaling pathway, p62/Keap1/Nrf2 signaling pathway. Activating p62/Keap1/Nrf2 signaling pathway inhibits ferroptosis. Nrf2/HO-1 signaling pathway promotes ferroptosis. Furthermore, some factors also participate in the occurrence of ferroptosis under hypoxia, such as HIF-1, NCOA4, DMT1. Meanwhile, ferroptosis is related with hypoxia-related diseases, such as MIRI, cancers, and AKI. Accordingly, ferroptosis appears to be a therapeutic target for hypoxia-related diseases.

Antineoplastic effects of cassava-cyanide extract on human glioblastoma (LN229) cells

Several natural compounds reduce tumour cell growth and metastasis by inducing programmed cell death. Cassava (Manihot esculenta Crantz) contains cyanogenic glycosides such as, linamarin and lotaustralin, can be enzymatically cleaved by linamarase to release hydrogen cyanide (HCN), which can have therapeutic benefits against hypertension, asthma, and cancer. We have developed a technology for isolating bio-active principles from cassava leaves.The present study is designed to analyze the cytotoxic effect of cassava cyanide extract (CCE) against human glioblastoma cells (LN229). The treatment of CCE demonstrated a dose dependent toxicity on glioblastoma cells. At higher concentration tested, the CCE (400 μg/mL) was found to be cytotoxic, reducing the cell viability to 14.07 ± 2.15% by negatively influencing the mitochondrial activity, and lysosomal and cytoskeletal integrity. Coomassie's brilliant blue staining confirmed cells' morphological aberration after 24 h of treatment with CCE. Moreover, DCFH-DA assay and Griess reagent showed an increase in ROS but a decrease in RNS production at a concentration of CCE. Flow cytometry analysis revealed that CCE interfered with G0/G1, S, and G2/M stages of the cell cycle of glioblastoma, and Annexin/PI staining indicated a dose-dependent increase in cell death, confirming the toxic nature of CCE on LN229 cells. These findings suggest that cassava cyanide extract has potential as an antineoplastic agent against glioblastoma cells, which is an aggressive and difficult-to-treat type of brain cancer. However, it is important to note that the study was conducted in vitro, and further research is necessary to assess the safety and efficacy of CCE in vivo. Additionally, it is essential to establish the optimal dose and potential side effects before considering its use as a therapeutic agent.

Denosumab Attenuates Glucolipotoxicity-Induced β-Cell Dysfunction and Apoptosis by Attenuating RANK/RANKL Signals.

Obesity is strongly associated with insulin sensitivity in type 2 diabetes (T2D), mainly because free fatty acids (FFAs) are released from excess fat tissue. Long-term exposure to high levels of FFAs and glucose leads to glucolipotoxicity, causing damage to pancreatic β-cells, thus accelerating the progression of T2D. Therefore, the prevention of β-cell dysfunction and apoptosis is essential to prevent the development of T2D. Unfortunately, there are currently no specific clinical strategies for protecting β-cells, highlighting the need for effective therapies or preventive approaches to improve the survival of β-cells in T2D. Interestingly, recent studies have shown that the monoclonal antibody denosumab (DMB), used in osteoporosis, displays a positive effect on blood glucose regulation in patients with T2D. DMB acts as an osteoprotegerin (OPG) by inhibiting the receptor activator of the NF-κB ligand (RANKL), preventing the maturation and function of osteoclasts. However, the exact mechanism by which the RANK/RANKL signal affects glucose homeostasis has not been fully explained. The present study used human 1.4 × 107 β-cells to simulate the T2D metabolic condition of high glucose and free fatty acids (FFAs), and it investigated the ability of DMB to protect β-cells from glucolipotoxicity. Our results show that DMB effectively attenuated the cell dysfunction and apoptosis caused by high glucose and FFAs in β-cells. This may be caused by blocking the RANK/RANKL pathway that reduced mammalian sterile 20-like kinase 1 (MST1) activation and indirectly increased pancreatic and duodenal homeobox 1 (PDX-1) expression. Furthermore, the increase in inflammatory cytokines and ROS caused by the RANK/RANKL signal also played an important role in glucolipotoxicity-induced cytotoxicity, and DMB can also protect β-cells by reducing the mechanisms mentioned above. These findings provide detailed molecular mechanisms for the future development of DMB as a potential protective agent of β-cells.