Intracellular ROS Accumulation Research Articles

Neuroprotective Effects of Extracts from Tiger Milk Mushroom Lignosus rhinocerus Against Glutamate-Induced Toxicity in HT22 Hippocampal Neuronal Cells and Neurodegenerative Diseases in Caenorhabditis elegans

Simple SummaryNeurodegenerative diseases are recognized as one of the major public health issues in aging populations worldwide. High reactive oxygen species (ROS) cause oxidative stress, leading to cellular injury and neuronal cell death. While it has been used as traditional medicine, little is known about the neuroprotective effect of the Tiger Milk Mushroom Lignosus rhinocerus (LR). The aims of this study were to investigate the neuroprotective effect of three extracts of LR, including ethanol extract (LRE), cold water extract (LRC) and hot water extract (LRH), against glutamate-induced oxidative stress in mouse hippocampal (HT22) cells (in vitro model) as well as to determine their effect in Caenorhabditis elegans (in vivo model). We found that only LRE exhibited neuroprotective effects both in vitro (alleviation of glutamate-induced ROS in HT22 cells, resulting in increased cell survival) and in vivo (prevention of neurotoxicity in C. elegans). Therefore, active chemical constituents in LRE may serve as neuroprotectant candidates. Nevertheless, LRE extracts should be extensively studied for their neuroprotective activity in the future.Despite the Tiger Milk Mushroom Lignosus rhinocerus (LR) having been used as a traditional medicine, little is known about the neuroprotective effects of LR extracts. This study aims to investigate the neuroprotective effect of three extracts of LR against glutamate-induced oxidative stress in mouse hippocampal (HT22) cells as well as to determine their effect in Caenorhabditis elegans. In vitro, we assessed the toxicity of three LR extracts (ethanol extract (LRE), cold-water extract (LRC) and hot-water extract (LRH)) and their protective activity by MTT assay, Annexin V-FITC/propidium iodide staining, Mitochondrial Membrane Potential (MMP) and intracellular ROS accumulation. Furthermore, we determined the expression of antioxidant genes (catalase (CAT), superoxide dismutase (SOD1 and SOD2) and glutathione peroxidase (GPx)) by qRT-PCR. In vivo, we investigated the neuroprotective effect of LRE, not only against an Aβ-induced deficit in chemotaxis behavior (Alzheimer model) but also against PolyQ40 formation (model for Morbus Huntington) in transgenic C. elegans. Only LRE significantly reduced both apoptosis and intracellular ROS levels and significantly increased the expression of antioxidant genes after glutamate-induced oxidative stress in HT22 cells. In addition, LRE significantly improved the Chemotaxis Index (CI) in C. elegans and significantly decreased PolyQ40 aggregation. Altogether, the LRE exhibited neuroprotective properties both in vitro and in vivo.

Fucoxanthin Prevents 6-OHDA-Induced Neurotoxicity by Targeting Keap1.

As the most abundant marine carotenoid extracted from seaweeds, fucoxanthin (FUC) is considered to have excellent neuroprotective activity. However, the target of FUC for its neuroprotective properties remains largely unclear. Oxidative stress is one of the initiating factors causing neuronal cell loss and necrosis, and it is also an important inducement of Parkinson's disease (PD). In the present study, the neuroprotective effect of FUC was assessed using a 6-hydroxydopamine- (6-OHDA-) induced neurotoxicity model. FUC suppressed 6-OHDA-induced accumulation of intracellular ROS, the disruption of mitochondrial membrane potential, and cell apoptosis through the Nrf2-ARE pathway. Keap1 as a repressor of Nrf2 can regulate the activity of Nrf2. Here, the biolayer interferometry (BLI) assay demonstrated that FUC specifically targeted Keap1 and inhibited the interaction between Keap1 and Nrf2. FUC bound to the hydrophobic region of Keap1 pocket and formed hydrogen bonding interactions with Arg415 and Tyr525. Besides, it also dose-dependently upregulated the expressions of antioxidant enzymes, such as nicotinamide heme oxygenase-1, glutamate-cysteine ligase modifier subunit, and glutamate-cysteine ligase catalytic subunit, in 6-OHDA-induced PC12 cells. In 6-OHDA-exposed zebrafish, FUC pretreatment significantly increased the total swimming distance of zebrafish larvae and improved the granular region of the brain tissue damage. These results suggested that FUC could protect the neuronal cells against 6-OHDA-induced injury via targeting Keap1.

Dimethyl fumarate ameliorates endotoxin-induced acute kidney injury against macrophage oxidative stress

Background Characterized by macrophage infiltration, renal inflammation during septic acute kidney injury (AKI) reveals a ubiquitous human health problem. Unfortunately, effective therapies with limited side effects are still lacking. This study is aiming to elucidate the role of Dimethyl fumarate (DMF) in macrophages against oxidative stress of septic AKI. Methods Balb/c mice were gavaged by 50 mg/kg DMF then injected with 10 mg/kg LPS by i.p. We examined LPS-induced renal dysfunction and histological features in murine kidneys. Raw264.7 macrophage cells were also treated with DMF and then induced by LPS. The mitotracker staining was used to follow mitochondria integrity by confocal microscopy. Flow cytometry measured the production of ROS by DCF-HDA and the expression of iNOS. Western blot detected the expression of Nrf-2 and Sirt1. Co-IP measured the interaction between Sirt1 and Nrf-2. Confocal microscopy observed the colocalization of Sirt1 and Nrf-2 in LPS-treated Raw264.7 macrophage cells. Results DMF ameliorated murine LPS nephritis with reduced blood urea nitrogen and serum creatinine, as well as decreased the histological alterations compared to the normal control. DMF significantly inhibited the expression of iNOS and reduced the production of nitrite in Raw264.7 cells following LPS treatment. Our study also revealed the role of DMF in protecting against intracellular ROS accumulation and mitochondria dysfunction in LPS-induced nephritis. DMF facilitated colocalization and interaction between Sirt1 and Nrf-2 in LPS-treated cells. Conclusions This study showed that DMF alleviated LPS-induced nephritis, indicating protective effects of DMF on macrophage against oxidative stress induced by LPS potentially involving Nrf-2-mediated pathway.

Cytotoxic Activity of Isoniazid Derivative in Human Breast Cancer Cells.

Isoniazid is an antibiotic used for the treatment of tuberculosis. Previously, we found that the isoniazid derivative (E)-N'-(2,3,4-trihydroxybenzylidene) isonicotinohydrazide (ITHB4) could be developed as novel antimycobacterial agent by lead optimization. We further explored the ability of this compound compared to zerumbone in inhibiting the growth of MCF-7 breast cancer cells. Cytotoxicity was measured by the MTT assay and further confirmed via apoptosis, ROS, cell cycle, DNA fragmentation and cytokine assays. ITHB4 demonstrated a lower IC50 compared to zerumbone in inhibiting the proliferation of MCF-7 cells. ITHB4 showed no toxicity against normal breast and human immune cells. Apoptosis assay revealed that ITHB4, at a concentration equal to the IC50, induces apoptosis of MCF-7 cells and cell cycle arrest at the sub-G1 and G2/M phases. ITHB4 triggered accumulation of intracellular ROS and nuclear DNA fragmentation. Secretion of pro-inflammatory cytokines induced inflammation and potentially immunogenic cell death. ITHB4 has almost similar chemotherapeutic properties as zerumbone in inhibiting MCF-7 growth, and hence provide the basis for further experiments in animal models.

FAM134B-Mediated ER-phagy Upregulation Attenuates AGEs-Induced Apoptosis and Senescence in Human Nucleus Pulposus Cells.

Previous studies have established the pathogenic role of advanced glycation end products (AGEs) accumulation in intervertebral disc degeneration (IDD). Emerging evidence indicates that ER-phagy serves as a crucial cellular adaptive mechanism during stress conditions. This study is aimed at investigating the role of FAM134B-mediated ER-phagy in human nucleus pulposus (NP) cells upon AGEs treatment and exploring its regulatory mechanisms. We observed that AGEs treatment resulted in significantly increased apoptosis, senescence, and ROS accumulation in human NP cells; meanwhile, the enhanced apoptosis and senescence by AGEs treatment could be partially alleviated with the classic ROS scavenger NAC administration. Furthermore, we confirmed that FAM134B-mediated ER-phagy was activated under AGEs stimulation via ROS pathway. Importantly, it was also found that FAM134B overexpression could efficiently relieve intracellular ROS accumulation, apoptosis, and senescence upon AGEs treatment; conversely, FAM134B knockdown markedly resulted in opposite effects. In conclusion, our data demonstrate that FAM134B-mediated ER-phagy plays a vital role in AGEs-induced apoptosis and senescence through modulating cellular ROS accumulation, and targeting FAM134B-mediated ER-phagy could be a promising therapeutic strategy for IDD treatment.

Traditional Uyghur medicine Quercus infectoria galls water extract triggers apoptosis and autophagic cell death in colorectal cancer cells

BackgroundThe water extract of Quercuse infectoria galls (QIG) is the active ingredient of Uyghur medicine Xipayi Kui Jie’an (KJA) which has promising therapeutic effects on Ulcerative Colitis (UC) as an alternative medicine. Considering the relationship between UC and the development of colorectal cancer (CRC), the present work aims to explore the direct anti-CRC activity of QIG extract.MethodsCCK8 assay and flow cytometry were used to detect cytotoxicity and apoptosis. Transmission electron microscopy (TEM), flow cytometry, laser confocal and western blotting were performed to examine autophagy. We also adopted Reactive Oxygen Assay kit, as well as transwell and wound healing tests to study the underlying mechanism of QIG against CRC cells.ResultsFirst, we found that QIG extract could suppress the viability of CRC cells and trigger caspases-dependent apoptosis. Subsequently, we proved for the first time that QIG extract also triggered autophagic cell death in CRC cells, which together with apoptosis contributed to the cytotoxic effect on CRC cells. Further investigation revealed that QIG-induced cytotoxicity associated with intracellular ROS accumulation which could suppress the AKT/mTOR signaling pathway, and then induce autophagy and inhibit cell growth. Besides, Erk signaling pathway was also involved in the process of autophagic cell death. Moreover, QIG extract also influenced EMT process and inhibited CRC cell migration.ConclusionAltogether, this study provides a basis for the utilization of QIG as an alternative medicine for CRC prevention and treatment.

A proteoglycan extract from Ganoderma Lucidum protects pancreatic beta-cells against STZ-induced apoptosis.

The pancreatic β-cell death or dysfunction induced by oxidative stress plays an important effect on the development and progression of diabetes mellitus. Based on our previous findings, a natural proteoglycan extracted from Ganoderma Lucidum, named FYGL, could treat T2DM in vivo. In this study, we investigated the effects of FYGL on STZ-induced apoptosis of INS-1 cells and its underlying mechanisms. The results showed that FYGL significantly improved the cell viability and alleviated the apoptosis in STZ-treated INS-1 cells. Moreover, FYGL markedly decreased the intracellular ROS accumulation and NO release, and deactivated NF-κB, JNK, and p38 MAPK signaling pathways in STZ-induced INS-1 cells. Furthermore, FYGL improved the insulin secretion through inhibiting the activation of JNK and improving the expression of Pdx-1 in INS-1 cells damaged by STZ. These results indicated that FYGL could protect pancreatic β-cells against apoptosis and dysfunction, and be used as a promising pharmacological medicine for diabetes management. Abbreviations: T2DM: type 2 diabetes mellitus; FYGL: Fudan-Yueyang G. lucidum; ROS: reactive oxygen species; NO: reactive oxygen species; NF-κB: nuclear factor kappa beta; JNK: c-jun N-terminal kinase; MAPK: mitogen-activated protein kinase; Pdx-1: Pancreatic duodenal homeobox 1.

Comparative Acute Toxicity and Oxidative Stress Responses in Three Aquatic Species Exposed to Stannic Oxide Nanoparticles and Stannic Chloride.

We experimentally investigated the toxicity of stannic oxide nanoparticles (SnO2 NPs) to three freshwater species including Scenedesmus obliquus, Daphnia magna, and Danio rerio. To evaluate effect, toxicological impacts were compared to that of stannic chloride (SnCl4). Based on the actual concentration of Sn, SnO2 NPs suspensions inhibited growth of S. obliquus in a dose-dependent manner, demonstrating a median effect concentration of 2.28 ± 0.53mg/L. However, SnO2 NP suspensions were found to exhibit limited acute toxicity in D. magna and D. rerio. Moreover, the toxicity of the SnO2 NP suspension was lower than SnCl4 for all three trophic aquatic organisms. Comparison of component-specific contribution to overall toxicity indicated that, in SnO2 NP suspensions, particulate Sn more significantly contributed to toxicity than dissolved Sn-ions. Furthermore, we found that the toxic mechanism of the SnO2 NP suspension involved the induction of oxidative stress by increasing intracellular ROS accumulation.

Extension of life span and stress tolerance modulated by DAF-16 in Caenorhabditis elegans under the treatment of Moringa oleifera extract.

The present study was focused to isolate the bioactive compounds present in the leaves of Moringa oleifera which contains a high nutritional value. Furthermore, the research was aimed to evaluate the antioxidant, anti-aging, and anti-neurodegenerative properties of M. oleifera using the experimental model Caenorhabditis elegans. The separation of compounds from the crude extract and its identification was carried out through TLC, Column chromatography, UV absorption spectroscopy, and GC-MS. The compounds identified in most abundant fraction of column chromatography were [Phenol-2,4-bis(1,1-dimethylethyl)- phosphite (3:1)] and Tetratetracontane. The result suggests that the leaves extracts and column fraction were able to significantly extend the life span of the N2 wild-type strain of C. elegans. The most potent life span extending effect was displayed by the dichloromethane extract of leaves which was 21.73 ± 0.142days compared to the control (16.55 ± 0.02days). It could also extend the health span through improved physiological functions such as pharyngeal pumping, body bending, and reversal frequency with increased age. The treated worms were also exhibited improved resistance to thermal stress, oxidative stress, and reduced intracellular ROS accumulation. Moreover, the leaves extract could elicit neuroprotection as it could delay the paralysis in the transgenic strain of C. elegans 'CL4176' integrated with Aβ. Interestingly, The RNAi experiment demonstrated that the extended life span under the treatment of extracts and the compound was daf-16 dependent. In transgenic C. elegans TJ356, the DAF-16 transcription factor was localized in the nucleus under the stress conditions, further supported the involvement of the daf-16 gene in longevity. Overall, the study suggests the potential of M. oleifera as a dietary supplement and alternative medicine to defend against oxidative stress and aging.

CircCOG8 Downregulation Contributes to the Compression-Induced Intervertebral Disk Degeneration by Targeting miR-182-5p and FOXO3.

Circular RNAs (circRNAs) have been increasingly demonstrated to play critical roles in the pathogenesis of various human diseases. Intervertebral disk degeneration (IDD) is recognized as the major contributor to lower back pain, and mechanical stress is a predominant trigger for IDD. However, little is known about the part that circRNAs play in the involvement of mechanical stress during IDD development. In the present study, we identified a novel circRNA and examined the role of this circRNA in a compression loading-induced IDD process. We detected the expression pattern of circCOG8 and observed its function in disk NP cells under mechanical stress. We conducted bioinformatics analysis, RNA immunoprecipitation experiment, and reporter gene assay to unveil the mechanism of the circCOG8 downregulation mediated IVD degeneration. Results showed that the circCOG8 expression was obviously down-regulated by the mechanical stress in disk NP cells. CircCOG8 attenuated NP cells apoptosis, intracellular ROS accumulation, and ECM degradation in vitro and ex vivo. CircCOG8 directly interacted with miR-182-5p and, thus, modulated the FOXO3 expression to affect the compression-induced IDD progression. Altogether, the present study revealed that the circCOG8/miR-182-5p/FOXO3 pathway was an important underlying mechanism in the involvement of compression during the IDD progression. Intervention of circCOG8 is a new therapeutic strategy for IDD treatment.

Phytochemicals, antioxidant and anti-proliferative activities of Myrtus communis L. genotypes from Tunisia

Myrtle (Myrtus communis L.) has long been regarded as a medicinal and aromatic plant. The analysis of phenolic and terpenic compounds contained in the leaf extracts of three Myrtle genotypes showed their richness in monoterpene hydrocarbons (48, 32%, 83.77%), flavonols, and hydrolysable tannins. Phenolic profiles and volatile compounds varied significantly among genotypes. All leaves extracts revealed excellent DPPH scavenging activity and β-carotene bleaching inhibition capacity (IC50=3.81 µg/ml, IC50= 3.58 µg/ml, respectively). The MTT metabolism assay demonstrated the efficacy of M. communis genotypes against PC12 cancer cell proliferation and their safety towards normal cells. Caspases 3/7 induction, apoptosis and intracellular ROS accumulation of treated cancer cell lines proved the cytotoxic effect of M. communis genotypes. This cytotoxic activity could be related to the antioxidant properties of the studied extracts. Antioxidant and antiproliferative activities varied significantly among genotypes. Such variation is attributed to chemical composition differences. Our results highlighted the interest of use of M. communis extracts as an industrial crop or as an ingredient in functional foods.

Tartary buckwheat protein hydrolysates enhance the salt tolerance of the soy sauce fermentation yeast Zygosaccharomyces rouxii

Supplementation of protein hydrolysate is an important strategy to improve the salt tolerance of soy sauce aroma-producing yeast. In the present study, Tartary buckwheat protein hydrolysates (BPHs) were prepared and separated by ultrafiltration into LM-1 (<1 kDa) and HM-2 (1–300 kDa) fractions. The supplementation of HM-2 fraction could significantly improve cell growth and fermentation of soy sauce aroma-producing yeast Zygosaccharomyces rouxii As2.180 under high salt (12%, w/w) conditions. However, the LM-1 fraction inhibited strain growth and fermentation. The addition of HM-2 promoted yeast cell accumulation of K+, removal of cytosolic Na+ and accumulation of glycerol. Furthermore, the HM-2 fraction improved the cell membrane integrity and mitochondrial membrane and decreased intracellular ROS accumulation of the strain. The above results indicated that the supplementation of BPHs with a molecular weight of 1–300 kDa is a potentially effective and feasible strategy for improving the salt tolerance of soy sauce aroma-producing yeast Z. rouxii.

Exogenous application of phytosulfokine α (PSKα) delays senescence in broccoli florets during cold storage by ensuring intracellular ATP availability and avoiding intracellular ROS accumulation

During postharvest life, broccoli suffers from florets yellowing, which reduces its economic and nutritional value. We investigated the mechanisms employed by exogenous phytosulfokine α (PSKα) applying at 150 nM for delaying senescence in broccoli florets stored at 4 °C for 28 days. The results showed that the SnRK1 gene expression was higher in broccoli florets treated with 150 nM PSKα, which may warrant sufficient intracellular availability of ATP, resulted from a higher activity of H+-ATPase, Ca2+-ATPase, succinate dehydrogenase (SDH), and cytochrome c oxidase (CCO). In addition, avoiding H2O2 accumulation by higher expression of alternative oxidase (AOX) and uncoupling protein (UCP1) genes may arise from higher SnRK1 gene expression. Additionally, lower mitochondrial permeability transition pore (mPTP) opening may avoid ROS accumulation in broccoli florets treated with 150 nM PSKα. Taken together, our results assume that exogenous PSKα application as signaling bioactive peptide could be considered as a promising procedure for delaying senescence of broccoli florets during cold storage.

Thymol as a critical component of Thymus vulgaris L. essential oil combats Pseudomonas aeruginosa by intercalating DNA and inactivating biofilm

Pseudomonas aeruginosa is a notoriously difficult pathogen to control with antibiotics and disinfectants. Thymus vulgaris L. essential oil (TEO) and thymol are useful for replacing synthetic bacteriostatic agents due to their broad-spectrum bactericidal properties. This study focuses on understanding the inhibitory effects of TEO and its major component against P. aeruginosa, and exploring the antibacterial mechanism from the perspectives of cell membrane destruction, DNA intercalation and biofilm prevention. Results indicate that thymol is the principal component in TEO, as confirmed by GC-MS analysis. TEO and thymol potently combat the planktonic P. aeruginosa and directly change the cell structure. P. aeruginosa cell membrane integrity is destroyed as evidenced by an increase in permeability of the inner and outer membranes and the leakage of intracellular biological macromolecules (DNA). Our study further confirms that the accumulation of intracellular ROS caused by TEO and thymol can result in oxidative stress-mediated DNA damage. Thymol intercalates in the P. aeruginosa genomic DNA to affect the normal function of DNA and even cause bacterial death. Moreover, TEO and thymol affect the biofilm formation and limit the bacterial swimming and swarming motilities. This study provides a potential approach for the development and utilization of natural essential oils and bioactive compunds as novel food additives in the food processing.

Altered oxidative stress markers in relation to T cells, NK cells & killer immunoglobulin receptors that are associated with disease activity in SLE patients.

Systemic Lupus Erythematosus is an autoimmune disease with symptoms pervasive to all organ systems. It affects more females as compared to males (in the ratio 9:1). Oxidative stress plays a major role in the pathogenesis of SLE and other autoimmune diseases. In order to understand the relationship between cell specific oxidative stress and the severity of SLE, this research study involving the estimation of intracellular ROS accumulation in T and NK cell was conducted on SLE patients of North Indian Population. At the same time, to estimate anti-oxidant defense, Keap1 and Nrf2 levels were estimated in these cell types. The relationship between the expression of Killer immunoglobulin receptors i.e., KIR2DL4 & KIR3DL1 and oxidative stress was also evaluated as these receptors are imperative for the function and self-tolerance of NK cells.Oxidative stress was raised along with Keap1 and Nrf2 in T and NK cell subsets in SLE patients. The expression of KIR2DL4 was raised and that of KIR3DL1 was reduced in the NK cells of patients. The intensity of change in expression and its significance varied among the subsets. Nrf2 expression was raised in these species against oxidative stress as the antioxidant defense mechanism pertaining to Keap1-Nrf2 pathway, but the adequacy of response needs to be understood in further studies. The expression of KIR2DL4 and KIR3DL1 varied among the patient and healthy controls and the expression of the latter was found to have a significant positive relationship with plasma Glutathione(reduced) concentration.

Chemo-Radiative Stress of Plasma as a Modulator of Charge-Dependent Nanodiamond Cytotoxicity

Efficient and selective internalization of nanoscale diamonds (also termed nanodiamonds, NDs) by living cells is of fundamental importance for their bionanotechnological applications. The biocompatibility of NDs is well established and has been suggested to arise from the limited membrane perturbation during their cellular translocation. However, the latter may be affected when cells are subjected to external stress. This study shows that the oxidative stress generated by atmospheric pressure cold plasmas (APCP) alters cell sensitivity to NDs, and their cytotoxicity profile. Both positively and negatively charged NDs are nontoxic to cells, here Saccharomyces cerevisiae and human cell lines, i.e., near-normal human mammary epithelial cells (MCF-10A) and breast cancer cells (MDA-MB-468 and T47D), unless the APCP stress is introduced. A brief exposure of the cells to APCP leads to a significant increase in their ND affinity (uptake and/or surface attachment) and intracellular ROS accumulation, particularly for positively charged NDs and both yeast and cancer cells. A concomitant decrease in cell viability and yeast cell growth, reflected by longer lag phases and lower cell density after 24 h of incubation, demonstrates a considerably enhanced ND toxicity to these cells. These results suggest that chemo-radiative stress, such as that produced by plasma, may influence the toxicity of nanoparticles to different cells, with specificity achieved through controlling particle charges. Moreover, since oxidative stress is not only associated with the use of APCP but can arise unintentionally within an organism and/or in the environment, these findings may have broader implications for the use of nontoxic nanoparticles in bionanotechnology in general.

493-P: Cardiac Microvascular Endothelial Enhancement of Cardiomyocyte Function Is Impaired by Uremic Serum and Restored by Empagliflozin

Background: It has been proposed that diabetes and chronic kidney disease cause heart failure with preserved ejection fraction (HFpEF) through low-grade inflammation and microvascular endothelial dysfunction. We have previously shown that endothelial enhancement of cardiomyocyte contraction and relaxation is mediated by NO, impaired by cytokines, and restored upon treatment with the SGLT2 inhibitor Empagliflozin. Chronic kidney disease (CKD) is linked to diabetes and HFpEF and causes systemic endothelial dysfunction. Objective: To test the hypothesis that uremic serum from patients with CKD impairs endothelial control of cardiomyocyte contraction and relaxation, and that Empagliflozin protects against this effect. Methods and Results: Co-culture of rat cardiomyocytes (CM) with human cardiac microvascular endothelial cells (CMECs) enhanced their contraction and relaxation. Pre-treatment with serum from patients with CKD abrogated these effects of CMEC, and treatment of CMECs with Empagliflozin restored the effects of CMECs on CM function. Exposure of CMECs to the uremic serum reduced endothelial NO bioavailability and increased intracellular reactive oxygen species ROS by increasing ROS generation by mitochondria. Uremic serum also increased 3-nitrotyrosine (3-NT) level, indicating scavenging of NO by ROS. Empagliflozin attenuated uremic serum-induced mitochondrial and intracellular ROS, leading to restoration of endothelial NO bioavailability. Conclusions: Exposure of CMECs to serum from CKD patients impairs CMEC-mediated enhancement of CM contraction and relaxation. Empagliflozin restores the beneficial effect of CMECs on CM function by reducing mitochondrial oxidative damage, leading to a decrease in intracellular ROS accumulation and increased endothelial NO bioavailability. Disclosure R. Juni: None. R. Al-Shama: None. D. Kuster: None. J. van der Velden: None. M. Vervloet: None. W. Paulus: None. E.C. Eringa: None. P. Koolwijk: None. V.W. van Hinsbergh: None. Funding Netherlands Heart Foundation

RETRACTED ARTICLE: Structural Characterization and Anti-Colon Cancer Activity of a Three-Dimensional Anionic Indium(III) Coordination Polymer

Solvothermal treatment of indium(III) nitrate with flexible pseudo-C3-symmetric tricarboxylic acid in the presence of NaCl at 120 °C for three days in a mixed solvent of DMF and CH3CN yields a new 3D anionic indium carboxylate framework {[(CH3)2NH2)In(L)(Cl)](DMF)}n(1) (H3L = 2,4,6-tris[(4-carboxyphenoxy)methyl]-1,3,5-trimethylbenzene), existing as a three-dimensional framework with a 2-fold interpenetrated network. The as-prepared polymer is characterized by the elemental analysis and single crystal X-ray diffraction. DMF undergoes cleavage to dimethyl ammonium ions incorporated in the pores of the framework. Furthermore, a sonochemical method is used to produce nanostructures of complex 1. Then, the in vitro anti-colon cancer activity of nano-1 is assessed with CCK-8. Annexin V-FITC/ PI and DCFH-DA detection is recruited for the cell apoptosis and the intracellular ROS accumulation assay, respectively.

Globular CTRP9 protects cardiomyocytes from palmitic acid-induced oxidative stress by enhancing autophagic flux

BackgroundOxidative stress in cardiac myocytes is an important pathogenesis of cardiac lipotoxicity. Autophagy is a cellular self-digestion process that can selectively remove damaged organelles under oxidative stress, and thus presents a potential therapeutic target against cardiac lipotoxicity. Globular CTRP9 (gCTRP9) is a newly identified adiponectin paralog with established metabolic regulatory properties. The aim of this work is to investigate whether autophagy participates the protection effects of gCTRP9 in neonatal rat cardiac myocytes (NRCMs) under oxidative stress and the underlying mechanism. ResultsNRCMs were treated with PA of various concentrations for indicated time period. Our results showed that PA enhanced intracellular ROS accumulation, decreased mitochondrial membrane potential (Δψm) and increased activation of caspases 3. These changes suggested lipotoxicity due to excessive PA. In addition, PA was observed to impair autophagic flux in NRCMs and impaired autophagosome clearance induced by PA contributes to cardiomyocyte death. Besides, we found that gCTRP9 increased the ratio of LC3II/I and the expression of ATG5 which was vital to the formation of autophagosomes and decreased the level of P62, suggesting enhanced autophagic flux in the absence or presence of PA. The result was further confirmed by the methods of infection with LC3-mRFP-GFP lentivirus and blockage of autophagosome–lysosome fusion by BafA1. Moreover, gCTRP9 reestablished the loss of mitochondrial membrane potential, suppressed ROS generation, and reduced PA -induced myocyte death. However, the protective effect of gCTRP9 on the cardiac lipotoxicity was partly abolished by blockade of autophagy by autophagy-related 5 (ATG5) siRNA, indicating that the effect of gCTRP9 on cell survival is critically mediated through regulation of autophagy. ConclusionAutophagy induction by gCTRP9 could be utilized as a potential therapeutic strategy against oxidative stress-mediated damage in cardiomyocytes.

Molecular Hydrogen Protects Human Melanocytes from Oxidative Stress by Activating Nrf2 Signaling

Oxidative stress is proven to be critical for the initiation and progression of vitiligo. Molecular hydrogen (H2) possesses potent antioxidant activity and has been shown to protect against various oxidative stress-related diseases. In this study, we first investigated the effects and mechanisms of H2 in human melanocytes damaged by hydrogen peroxide. We initially found that H2 reduced intracellular ROS accumulation and malondialdehyde levels in both vitiligo specimens and hydrogen peroxide-treated melanocytes invitro in a concentration- and time-dependent manner, concomitant with the enhancement of antioxidant enzyme activity. Correspondingly, H2 reversed hydrogen peroxide-induced apoptosis and dysfunction in both normal and vitiligo melanocytes. H2 protected mitochondrial morphology and function in melanocytes under stress and promoted the activation of Nrf2 signaling, whereas Nrf2 deficiency abolished the protective effect of H2 against hydrogen peroxide-induced oxidative damage. Furthermore, H2 positively modulated β-catenin in hydrogen peroxide-treated melanocytes, and the β-catenin pathway was implicated in H2-induced Nrf2 activation. Collectively, our results indicate that H2 could be a promising therapeutic agent for vitiligo treatment via attenuating oxidative damage, and its beneficial effect in human melanocytes might involve Wnt/β-catenin-mediated activation of Nrf2 signaling.