Oxidative Stress-related Apoptosis Research Articles

HPLC-DAD-ESI-QTOF-MS/MS profiling of Zygophyllum album roots extract and assessment of its cardioprotective effect against deltamethrin-induced myocardial injuries in rat, by suppression of oxidative stress-related inflammation and apoptosis via NF-κB signaling pathway.

Zygophyllum album is widely used to treat many cardiovascular diseases (CVDs) and as anti-inflammatory plant. This study aimed to investigate the mechanism of the potential protective effects of Zygophyllum album roots extract (ZARE) against myocardial damage and fibrosis induced by a chronic exposure to deltamethrin (DLM) in rats. Bioactive compounds present in ZARE were analyzed by HPLC-DAD-ESI-QTOF-MS/MS. In vivo, DLM (4 mg/kg body weight), ZARE (400 mg/kg body weight) and DLM with ZARE were administered to rats orally for 60 days. Biochemical markers (LDH, ALT, CK, CK-MB and cTn-I) were assessed in the plasma by an auto-analyzer. Pro-inflammatory cytokines (TNF-α, IL-1β, and IL-6) were evaluated by a sandwich ELISA. NF-κB was quantified at mRNA levels by real time PCR. Heart tissue was used to determine cardiac oxidative stress markers (MDA, PC, SOD, CAT, and GPx). Masson's Trichrome (MT) and Sirius Red (SR) stainings were used for explored fibrosis statues. Phytochemical analysis using HPLC-DAD-ESI-QTOF-MS/MS revealed the presence of twenty six molecules including phenolic compounds and saponins. ZARE significantly improved the heart injury markers (LDH, ALT, CK, CK-MB and cTn-I), lipid peroxidation (MDA), protein oxidation (PC), antioxidant capacity (SOD, CAT, and GPx), and DNA structure, which were altered by DLM exposure. Moreover, ZARE cotreatment reduced the expressions of NF-κB, decreased plasmatic pro-inflammatory cytokines concentration (TNF-α, IL-1β and IL-6), and suppressed the myocardial collagen deposition, as observed by Sirius Red and Masson's Trichrome staining. ZARE ameliorated the severity of DLM-induced myocardial injuries through improving the oxidative status and reducing profibrotic cytokines production. The ZARE actions could be mediated by downregulation of NF-κB mRNA.

RNA-Seq analysis and functional characterization revealed lncRNA NONRATT007560.2 regulated cardiomyocytes oxidative stress and apoptosis induced by high glucose.

Hyperglycemia in diabetic patients would cause cardiomyocytes oxidative stress and apoptosis due to the excessive reactive oxygen species (ROS) accumulation, leading to progressive deterioration of cardiac structure and function. Long noncoding RNAs (lncRNAs) play essential roles on controlling oxidative stress and apoptotic activity. In the present study, RNA sequencing was used to detect the differentially expressed lncRNAs during high glucose-induced cardiomyocytes oxidative stress and apoptosis. A total of 306/400 lncRNAs were identified as differentially expressed, including 156/198 lncRNAs with increased expression and 150/202 lncRNAs with decreased expression at 24 hours/48 hours after high-glucose stimulation respectively. Among these dysregulated lncRNAs, 45 lncRNAs were consistently differentially expressed in cardiomyocytes at both two time points after high-glucose stimulation. Twenty lncRNAs were upregulated and 25 lncRNAs were downregulated at both 24 hours and 48 hours, respectively. The top three upregulated lncRNAs, NONRATT029805.2, NONRATT007560.2, and NONRATT002486.2 were selected for functional studies to determine the role in oxidative stress-related apoptosis. The results showed that inhibition of non-ratt007560.2 could abate the formation of ROS and reduce apoptosis, suggesting NONRATT007560.2 might play critical roles in the development of cardiomyopathy. The dysregulated lncRNAs might participate in regulating cardiomyocytes oxidative stress and apoptosis. These findings would be important theoretical and experimental basis for investigation on diabetic cardiomyopathy pathogenesis.

Curcumin- and Fish Oil-Loaded Spongosome and Cubosome Nanoparticles with Neuroprotective Potential against H2O2-Induced Oxidative Stress in Differentiated Human SH-SY5Y Cells

Many phytochemical antioxidant compounds, including curcumin (CU), are water-insoluble and thus require delivery carriers in order to increase their bioavailability for in vivo applications. Oxidative stress-related apoptosis is a common cause for the neuronal loss in the progression of neurodegenerative diseases. Lipid nanoparticles (NPs) with internal self-assembled liquid crystalline structures present strong interest as safe drug delivery systems for neuronal regeneration through combination therapies. Here, we report spongosome and cubosome lipid NPs, which co-encapsulate CU and fish oil (FO), rich in ω-3 polyunsaturated fatty acids. The performed structural investigation by synchrotron small-angle X-ray scattering evidenced the liquid crystalline organization of the self-assembled NPs. The encapsulation efficiency for CU in the lipid nanocarriers was found to be higher as compared to that reported for polymer-based carriers. The cytotoxicity of the blank and antioxidant-loaded nanocarriers was negli...

LncRNA-CIR regulates cell apoptosis of chondrocytes in osteoarthritis.

Osteoarthritis (OA) is a complex chronic degenerative joint disease involving oxidative stress, inflammation, and apoptosis of chondrocytes. As decoys of micro RNAs, long non-coding RNAs (lncRNAs) play important roles in various biological processes. This study was designed to investigate the interactions between lncRNA-CIR, chondrocyte apoptosis, and the molecular mechanisms underlying OA. Primary cultured chondrocytes were stressed using H2 O2 , IL-1β, or TNF-ɑ to simulate conditions found in OA. Quantitative real-time PCR was performed to detect miR-130a, lncRNA-CIR, and Bim mRNA expression levels. Western blot analysis was used to detect Bim protein expression levels. Reactive oxygen species (ROS) levels were assayed by detecting the fluorescent signal of 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA). Cell apoptosis was measured with combined staining of PI and DAPI. lncRNA-CIR knockdown and miR-130a over-expression or inhibition were performed using small interfering RNAs, and miR-130 mimics or inhibitors, respectively. lncRNA-CIR is significantly upregulated in OA patients, accompanied by downregulation of miR-130a and upregulation of Bim. Bio-informatics analysis predicted miR-130a as a target of both lncRNA-CIR and Bim. While lncRNA-CIR knockdown significantly increased the expression of Bim, miR-130a significantly suppressed Bim expression, with accompanying increases of ROS level, inflammatory mediator release, cell apoptosis, and relative luciferase activity. The present findings demonstrated that the lncRNA-CIR/miR-130a/Bim axis is involved in oxidative stress-related apoptosis of chondrocytes in OA.

Allyl Sulfide Counteracts 1-Bromopropane-Induced Neurotoxicity by Inhibiting Neuroinflammation and Oxidative Stress

Chronic exposure to 1-bromopropane (1-BP), an alternative to ozone-depleting solvents, produces potential neurotoxicity in occupational populations. However, no therapeutic strategy is available currently. Accumulating evidence suggests that cytochrome P4502E1 (CYP2E1) is critical for the active metabolism of 1-BP. The purpose of this study is aimed to test whether inhibition of CYP2E1 by allyl sulfide, a specific inhibitor of CYP2E1, could be able to protect against 1-BP-induced neurotoxicity. Male Wistar rats were intoxicated with 1-BP for 9 continuous weeks with or without allyl sulfide pretreatment. Results clearly demonstrated that 1-BP exposure induced decrease in NeuN+ cells and increase in cleaved caspase-3 expression and TUNEL+ cells in motor cortex of rats, which was significantly ameliorated by allyl sulfide. Allyl sulfide treatment also recovered the motor performance of rats treated with 1-BP. Mechanistically, allyl sulfide-inhibited 1-BP-induced expression of CYP2E1 in microglia, which was associated with suppression of microglial activation and M1 polarization in motor cortex of rats. Reduced oxidative stress was also observed in rats treated with combined allyl sulfide and 1-BP compared with 1-BP alone group. Furthermore, we found that allyl sulfide abrogated 1-BP-induced activation of Nuclear factor(NF)-κB and GSH/Thioredoxin/ASK1 pathways, the key factor for the maintenance of M1 microglial inflammatory response and oxidative stress-related neuronal apoptosis, respectively. Thus, our results showed that allyl sulfide exerted neuroprotective effects in combating 1-BP-induced neurotoxicity through inhibition of neuroinflammation and oxidative stress. Blocking CYP2E1 activity by allyl sulfide might be a promising avenue for the treatment of neurotoxicity elicited by 1-BP and other related neurotoxicants.

Mesenchymal stromal cells attenuate sevoflurane-induced apoptosis in human neuroglioma H4 cells

BackgroundInhalation of sevoflurane can induce neuronal apoptosis, cognitive impairment and abnormal behaviors. Bone marrow mesenchymal stem cells (MSCs) can secret neurotrophic factors and cytokines to protect from oxidative stress-related neuronal apoptosis. However, whether MSCs can protect from sevoflurane-induced neuronal apoptosis and the potential mechanisms are unclear.MethodsA non-contact co-culture of MSCs with human neuroglioma H4 cells (H4 cells) was built. H4 cells were co-cultured with MSCs or without MSCs (control) for 24 h. The co-cultured H4 cells were exposed to 4% sevoflurane for 6 h. The levels of caspase-3, reactive oxygen species (ROS), adenosine triphosphate (ATP), and the release of cytochrome C were determined by Western blot and fluorescence assay.ResultsSevoflurane exposure significantly elevated the levels of cleaved caspase 3 and Bax in H4 cells. However, these phenomena were significantly offset by the co-culture with MSCs in H4 cells. Co-culture with MSCs before, but not after, sevoflurane exposure, significantly attenuated sevoflurane-induced ROS production in H4 cells. MSCs prevented sevoflurane-mediated release of cytochrome C from the mitochondria and production of ATP in H4 cells.ConclusionsOur study indicated that soluble factors secreted by MSCs attenuated the sevoflurane-induced oxidative stress and apoptosis of neuronal cells by preserving their mitochondrial function.

Rosiglitazone inhibits PM2.5-induced cytotoxicity in human lung epithelial A549 cells.

Exposure to fine particulate matter <2.5 µm in diameter (PM2.5) leads to global adverse health effects, including increases in morbidity and mortality of respiratory diseases. PM2.5 increases production of reactive oxygen species (ROS) in the lung, which further lead to oxidative stress, cell apoptosis and cell death. According to results of previous studies, oxidative stress and subsequent cell apoptosis can be reduced by peroxisome proliferator-activated receptor gamma (PPARγ) in various cell types, however, its role in oxidative stress-related cell apoptosis caused by PM2.5 in respiratory systems is unclear. Human lung alveolar epithelial A549 cells were exposed to PM2.5 with or without rosiglitazone (an agonist of PPARγ) treatment. Cellular apoptosis and intracellular oxidative stress were determined by flow cytometry based on FITC Annexin V and DCFH-DA fluorescence, respectively. Western blot was conducted to determine the expression of Bax, Bcl2, PPARγ, P-ERK1/2, ERK1/2, P-STAT3, and STAT3. PPARγ was downregulated in PM2.5-treated A549 cells, and application of rosiglitazone reduced PM2.5-mediated ROS generation and cell apoptosis. In addition, our results indicated that rosiglitazone treatment suppressed PM2.5-induced ERK1/2 and STAT3 activation. Collectively, these data suggested that rosiglitazone protects against PM2.5-induced ROS production and cell apoptosis and represses activation of ERK1/2 and STAT3 signaling in A549 cells. Our results indicated that rosiglitazone is a potential therapeutic agent for PM2.5-induced lung diseases.

Overtraining elevates serum protease level, increases renal p16INK4α gene expression and induces apoptosis in rat kidney

Overtraining is well known to cause oxidative stress-related apoptosis. However, it also can cause serum protease activity elevation. On the other hand, p16INK4α regulates kidney aging and apoptosis. Hitherto, no studies have determined the relation of overtraining with protease activity and p16INK4α expression regarding kidney apoptosis. The aim of this study was to determine the effects of overtraining on serum protease activity and renal p16INK4α expression, as well as its relation to renal apoptosis in Wistar rats. Thirty experimentally naive male Wistar albino rats (2.5–3 months old, weighing 150–200 g) were divided randomly into three groups: control (C) group (n = 10, without any training program), trained (T) group (n = 10, 30 min of swimming, 3 times a week for 3 weeks) and overtrained (OT) group (n = 10, 60 min of swimming, 7 times a week for 3 weeks). Overtraining increased MDA levels in OT group compare to C and T groups (p < 0.01). We showed that the OT group has a higher serum protease enzyme activity (p < 0.01) and p16INK4α mRNA (p < 0.01) than both C group and T group. In addition, no apoptotic cell was observed in kidneys isolated from the C group, while it was observed in both T and OT groups. There was a positive correlation between the serum protease enzyme activity (r = 0.867; p < 0.01) and p16INK4α mRNA level (r = 0.514; p < 0.01) with the apoptosis in the renal cells. In summary, our result indicated that overtraining elevates serum protease level, increases renal p16INK4α expression and induces apoptosis in rat kidney.

Dietary nitrate protects submandibular gland from hyposalivation in ovariectomized rats via suppressing cell apoptosis

Xerostomia, a major oral symptom of menopause, is a subjective feeling of dry mouth associated with oral pain and difficulties in deglutition and speech, which significantly reduces patient's quality of life. Dietary nitrate, which can be converted to nitric oxide, has multiple physiological functions in the body, including antioxidant activity and vasodilatation; however, its protective effect against xerostomia remains poorly understood. The present study aimed to evaluate the effects of dietary nitrate on estrogen deficiency-induced xerostomia. We established an ovariectomized (OVX) rat model, which included five groups: sham-operated, OVX, OVX + 0.4 mM nitrate, OVX + 2 mM nitrate, and OVX + 4 mM nitrate (n = 6). After ovariectomy, animals in the nitrate treatment groups received appropriate amounts of sodium nitrate dissolved in distilled water for 3 months. The results showed that nitrate treatment reduced body weight and water intake, and increased serum nitrate and nitrite levels. Furthermore, nitrate uptake increased saliva secretion as evidenced by saliva flow rates and aquaporin 5 expression, and alleviated histological lesions as evidenced by reduction of the fibrotic area and cell atrophy in the salivary glands. Although protective effects of nitrate against estrogen deficiency-induced xerostomia were observed at all doses, treatment with 2 mM nitrate was more effective than that with 0.4 mM and 4 mM nitrate. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and caspase-3 expression analyses showed that nitrate also protected cells from apoptosis, possibly through upregulation of Cu-Zn superoxide dismutase (Cu-Zn SOD) known to inhibit oxidative stress-related apoptosis. Our findings indicate that nitrate could improve functional activity of the salivary glands in OVX rats by suppressing apoptosis and upregulating Cu-Zn SOD expression, suggesting that dietary nitrate may potentially prevent hyposalivation in menopausal women.

Trehalose ameliorates oxidative stress-mediated mitochondrial dysfunction and ER stress via selective autophagy stimulation and autophagic flux restoration in osteoarthritis development

Oxidative stress-related apoptosis and autophagy play crucial roles in the development of osteoarthritis (OA), a progressive cartilage degenerative disease with multifactorial etiologies. Here, we determined autophagic flux changes and apoptosis in human OA and tert-Butyl hydroperoxide (TBHP)-treated chondrocytes. In addition, we explored the potential protective effects of trehalose, a novel Mammalian Target of Rapamycin (mTOR)-independent autophagic inducer, in TBHP-treated mouse chondrocytes and a destabilized medial meniscus (DMM) mouse OA model. We found aberrant p62 accumulation and increased apoptosis in human OA cartilage and chondrocytes. Consistently, p62 and cleaved caspase-3 levels increased in mouse chondrocytes under oxidative stress. Furthermore, trehalose restored oxidative stress-induced autophagic flux disruption and targeted autophagy selectively by activating BCL2 interacting protein 3 (BNIP3) and Phosphoglycerate mutase family member 5 (PGAM5). Trehalose could ameliorate oxidative stress-mediated mitochondrial membrane potential collapse, ATP level decrease, dynamin-related protein 1 (drp-1) translocation into the mitochondria, and the upregulation of proteins involved in mitochondria and endoplasmic reticulum (ER) stress-related apoptosis pathway. In addition, trehalose suppressed the cleavage of caspase 3 and poly(ADP-ribose) polymerase (PARP) and prevented DNA damage under oxidative stress. However, the anti-apoptotic effects of trehalose in TBHP-treated chondrocytes were partially abolished by autophagic flux inhibitor chloroquine and BNIP3- siRNA. The protective effect of trehalose was also found in mouse OA model. Taken together, these results indicate that trehalose has anti-apoptotic effects through the suppression of oxidative stress-induced mitochondrial injury and ER stress which is dependent on the promotion of autophagic flux and the induction of selective autophagy. Thus, trehalose is a promising therapeutic agent for OA.

Bleomycin-induced pulmonary toxicopathological changes in rats and its prevention by walnut extract

Oxidative stress-related inflammation and apoptosis are important pathogenic consequences, which result in acute pulmonary toxicity. Bleomycin (BLM) is used to treat various forms of cancers. However, its prolonged administration is associated with major toxicity to respiratory system. We studied the effect of walnut (Juglans regia) extract in a rat model of BLM-induced pulmonary toxicopathy. We also studied parameters of inflammation, apoptosis and oxidative stress in various groups of animals. Prophylactic treatment of total methanolic extract of walnut at the dose of 150mg/kg b.w. was given per os to Wistar rats for 14days prior to BLM exposure. A single intratracheal injection of BLM (10U/kg b.w.) was administered on the eleventh day of the treatment. There was a marked increase in the hydroxyproline level, lipid peroxidation, nitric oxide production, and in the activities of xanthine oxidase and myeloperoxidase in the lung tissue in BLM-treated animals when compared to control animals. BLM also decreased the activities of antioxidant enzymes such as glutathione reductase and catalase and increased the lung inflammation and apoptosis by upregulating the NF-κB signaling pathway and caspase-3 expression. Treatment with walnut extract attenuated these changes in a significant manner. Walnut extract significantly modulated the lung injury as measured by markers of cellular injury such as lactate dehydrogenase and alkaline phosphatase, total cell count, total protein and reduced glutathione in bronchoalveolar lavage fluid. Histological findings supported the protective effects of walnut extract against BLM-induced lung injury. Walnut which has been shown to have numerous medicinally valuable constituents including ellagic acid showed efficacy in preventing the various toxicopathological effects of BLM in rat lungs. Overall, walnut extract decreases BLM-induced oxidative stress and lung inflammation by modulating the alveolar macrophage inflammatory response in rats and thus protecting them from the pathological effect of BLM.

Mitochondrial Dysfunction in Atrial Tissue of Patients Developing Postoperative Atrial Fibrillation

Mitochondria are the major site of cellular oxidation. Metabolism and oxidative stress have been implicated as possible mechanisms for postoperative atrial fibrillation (POAF) after cardiac operations. Establishing the precise nature of mitochondrial dysfunction as an etiologic factor for oxidative stress-related cell death and apoptosis could further the understanding of POAF. To establish this relationship, mitochondrial function was studied in patients undergoing cardiac operations that developed POAF and compared it with patients without POAF. Right atrial tissue and serum samples were collected from 85 patients before and after cardiopulmonary bypass. Microarray analysis (36 patients) and RNA sequencing (5 patients) were performed on serum and atrial tissues, respectively, for identifying significantly altered genes in patients who developed POAF. On the basis of these results, Western blot was performed in 52 patients for the genes that were most altered, and functional pathways were established. POAF developed in 30.6% (n= 26) of patients. Serum microarray showed significant fold changes in the expression of 49 genes involved in inflammatory response, oxidative stress, apoptosis, and amyloidosis (p < 0.05) in the POAF group. Similarly, RNA sequencing demonstrated an increased expression of genes associated with inflammatory response, fatty acid metabolism, and apoptosis in the POAF group (false discovery rate > 0.05). Immunoblotting showed a significant increase in TNFAIP6 (tumor necrosis factor, α-induced protein 6; p= 0.02) and transforming growth factor-β (p= 0.04) after cardiopulmonary bypass in thePOAF group. There was a significant decrease in PGC-1α (peroxisome proliferator-activated receptor-γ coactivator-1α; p= 0.002) and CPT1 (carnitine palmitoyltransferase I; p < 0.0005) in the POAF group after cardiopulmonary bypass. Compared with patients without POAF, those with POAF demonstrated mitochondrial dysfunction at various levels that are suitable for potential pharmacotherapy.

Sirtuin 1 protects the aging heart from contractile dysfunction mediated through the inhibition of endoplasmic reticulum stress-mediated apoptosis in cardiac-specific Sirtuin 1 knockout mouse model

BackgroundThe longevity regulator Sirtuin 1 is an NAD+-dependent histone deacetylase that regulates endoplasmic reticulum stress and influences cardiomyocyte apoptosis during cardiac contractile dysfunction induced by aging. The mechanism underlying Sirtuin 1 function in cardiac contractile dysfunction related to aging has not been completely elucidated. MethodsWe evaluated cardiac contractile function, endoplasmic reticulum stress, apoptosis, and oxidative stress in 6- and 12month-old cardiac-specific Sirtuin 1 knockout (Sirt1−/−) and control (Sirt1f/f) mice using western blotting and immunohistochemistry. Mice were injected with a protein disulphide isomerase inhibitor. For in vitro analysis, cultured H9c2 cardiomyocytes were exposed to either a Sirtuin 1 inhibitor or activator, with or without a mitochondrial inhibitor, to evaluate the effects of Sirtuin 1 on endoplasmic reticulum stress, nitric oxide synthase expression, and apoptosis. The effects of protein disulphide isomerase inhibition on oxidative stress and ER stress-related apoptosis were also investigated. ResultsCompared with 6-month-old Sirt1f/f mice, marked impaired contractility was observed in 12-month-old Sirt1−/− mice. These findings were consistent with increased endoplasmic reticulum stress and apoptosis in the myocardium. Measures of oxidative stress and nitric oxide synthase expression were significantly higher in Sirt1−/− mice compared with those in Sirt1f/f mice at 6months. In vitro experiments revealed increased endoplasmic reticulum stress-mediated apoptosis in H9c2 cardiomyocytes treated with a Sirtuin 1 inhibitor; the effects were ameliorated by a Sirtuin 1 activator. Moreover, consistent with the in vitro findings, impaired cardiac contractility was demonstrated in Sirt1−/− mice injected with a protein disulphide isomerase inhibitor. ConclusionThe present study demonstrates that the aging heart is characterized by contractile dysfunction associated with increased oxidative stress and endoplasmic reticulum stress and Sirtuin 1 might have the ability to protect the aging hearts from the inhibition of endoplasmic reticulum-mediated apoptosis.

Curcumin alleviates lipopolysaccharide induced sepsis and liver failure by suppression of oxidative stress-related inflammation via PI3K/AKT and NF-κB related signaling.

In many liver disorders, oxidative stress-related inflammation and apoptosis are important pathogenic components, finally resulting in acute liver failure. Erythropoietin and its analogues are well known to influence the interaction between apoptosis and inflammation in brain and kidney. The study is to clarify the effect of curcumin, a natural plant phenolic food additive, on lipopolysaccharides (LPS)-induced acute liver injury of mice with endotoxemia and associated molecular mechanism from inflammation, apoptosis and oxidative stress levels. And curcumin, lowered serum cytokines, including Interleukin 1beta (IL-1β), Interleukin 6 (IL-6) and tumor necrosis factor (TNF-α), and improved liver apoptosis through suppressing phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) signaling pathway and inhibiting Cyclic AMP-responsive element-binding protein (CREB)/Caspase expression, and decreased oxidative stress-associated protein expression, mainly involving 2E1 isoform of cytochrome P450/nuclear factor E2-related factor 2/reactive oxygen species (CYP2E/Nrf2/ROS) signaling pathway, as well as liver nitric oxide (NO) production in LPS-induced mice. Moreover, curcumin regulated serum alanine transaminase (ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP), accelerated liver antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT), glutathione (GSH) and glutathione peroxidase (GSH-px) levels, and inhibited activation of the mitogen-activated protein kinases/c-Jun NH2-terminal kinase (P38/JNK) cascade in the livers of LPS-induced rats. Thus, curcumin treatment attenuates LPS-induced PI3K/AKT and CYP2E/Nrf2/ROS signaling and liver injury. Strategies to inhibit inflammation and apoptosis signaling may provide alternatives to the current clinical approaches to improve oxidative responses of endotoxemia.

Cardiac progenitor cell-derived exosomes prevent cardiomyocytes apoptosis through exosomal miR-21 by targeting PDCD4.

Cardiac progenitor cells derived from adult heart have emerged as one of the most promising stem cell types for cardiac protection and repair. Exosomes are known to mediate cell–cell communication by transporting cell-derived proteins and nucleic acids, including various microRNAs (miRNAs). Here we investigated the cardiac progenitor cell (CPC)-derived exosomal miRNAs on protecting myocardium under oxidative stress. Sca1+CPCs-derived exosomes were purified from conditional medium, and identified by nanoparticle trafficking analysis (NTA), transmission electron microscopy and western blotting using CD63, CD9 and Alix as markers. Exosomes production was measured by NTA, the result showed that oxidative stress-induced CPCs secrete more exosomes compared with normal condition. Although six apoptosis-related miRNAs could be detected in two different treatment-derived exosomes, only miR-21 was significantly upregulated in oxidative stress-induced exosomes compared with normal exosomes. The same oxidative stress could cause low miR-21 and high cleaved caspase-3 expression in H9C2 cardiac cells. But the cleaved caspase-3 was significantly decreased when miR-21 was overexpressed by transfecting miR-21 mimic. Furthermore, miR-21 mimic or inhibitor transfection and luciferase activity assay confirmed that programmed cell death 4 (PDCD4) was a target gene of miR-21, and miR-21/PDCD4 axis has an important role in anti-apoptotic effect of H9C2 cell. Western blotting and Annexin V/PI results demonstrated that exosomes pre-treated H9C2 exhibited increased miR-21 whereas decreased PDCD4, and had more resistant potential to the apoptosis induced by the oxidative stress, compared with non-treated cells. These findings revealed that CPC-derived exosomal miR-21 had an inhibiting role in the apoptosis pathway through downregulating PDCD4. Restored miR-21/PDCD4 pathway using CPC-derived exosomes could protect myocardial cells against oxidative stress-related apoptosis. Therefore, exosomes could be used as a new therapeutic vehicle for ischemic cardiac disease.

Systemic effects of AGEs in ER stress induction in vivo.

Emerging evidence indicates that accumulation of advanced glycation end products (AGEs) in human tissues may contribute to cell injury, inflammation and apoptosis through induction of endoplasmic reticulum (ER) stress. Human metabolism relies on ER homeostasis for the coordinated response of all metabolic organs by controlling the synthesis and catabolism of various nutrients. In vitro studies have demonstrated AGE-induced enhancement of unfolded protein response (UPR) in different cell types including endothelial, neuronal, pancreatic cells and podocytes, suggesting this crosstalk as an underlying pathological mechanism that contributes to metabolic diseases. In this minireview, we describe in vivo studies undertaken by our group and others that demonstrate the diverse systemic effects of AGEs in ER stress induction in major metabolic tissues such as brain, kidney, liver and pancreas of normal mice. Administration of high-AGEs content diet to normal mice for the period of 4weeks upergulates the mRNA and protein levels of ER chaperone Bip (GRP78) indicative of UPR initiation in all major metabolic organs and induces activation of the pivotal transcription factor XBP1 that regulates glucose and lipid metabolism. Furthermore, animals with genetic ablation of UPR-activated transcription factor C/EBP homologous protein CHOP allocated in high-AGEs diet, exhibited relative resistance to UPR induction (BiP levels) and XBP1 activation in major metabolic organs. Since CHOP presents a critical mediator that links accumulation and aggregation of unfolded proteins with induction of oxidative stress and ER stress-related apoptosis, it is revealed as an important molecular target for the management of metabolic diseases.

4-Nonylphenol induces disruption of spermatogenesis associated with oxidative stress-related apoptosis by targeting p53-Bcl-2/Bax-Fas/FasL signaling.

4-Nonylphenol (NP) is a ubiquitous environmental chemical with estrogenic activity. Our aim was to test the hypothesis that pubertal exposure to NP leads to testicular dysfunction. Herein, 24 7-week-old rats were randomly divided into four groups and treated with NP (0, 25, 50, or 100 mg/kg body weight every 2 days for 20 consecutive days) by intraperitoneal injection. Compared to untreated controls, the parameters of sperm activation rate, curvilinear velocity, average path velocity, and swimming velocity were significantly lower at doses of 100 mg/kg, while sperm morphological abnormalities were higher, indicating functional disruption and reduced fertilization potential. High exposure to NP (100 mg/kg) resulted in disordered arrangement of spermatoblasts and reduction of spermatocytes in seminiferous tubules, while tissues exhibited a marked decline in testicular fructose content and serum FSH, LH, and testosterone levels. Oxidative stress was induced by NP (50 or 100 mg/kg) as evidenced by elevated MDA, decreased SOD and GSH-Px, and inhibited antioxidant gene expression (CAT, GPx, SOD1, and CYP1B1). In addition, NP treatment decreased proportions of Ki-67-positive cells and increased apoptosis in a dose-dependent manner. Rats treated with 100 mg/kg NP exhibited significantly increased mRNA expression of caspase-1, -2, -9, and -11, decreased caspase-8 and PCNA1 mRNA expression, downregulation of Bcl-2/Bax ratios and upregulation of Fas, FasL, and p53 at the protein and mRNA levels. Taken together, NP-induced apoptosis, hormonal deficiencies, and depletion of fructose potentially impairs spermatogenesis and sperm function. p53-independent Fas/FasL-Bax/Bcl-2 pathways may be involved in NP-induced oxidative stress-related apoptosis. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 739-753, 2017.

Quercetin and vitamin E attenuate Bonny Light crude oil-induced alterations in testicular apoptosis, stress proteins and steroidogenic acute regulatory protein in Wistar rats

Studies have shown the reproductive effects of Bonny Light crude oil (BLCO) via the mechanism of oxidative stress and testicular apoptosis. We investigated the protective role of quercetin and vitamin E on BLCO-induced testicular apoptosis. Experimental rats were divided into four groups of four each. Animals were orally administered 2 ml/kg corn oil (control: group 1), BLCO-800 mg/kg body weight + 10 mg/kg quercetin (group 2), BLCO-800 mg/kg body weight + 50 mg/kg vitamin E (group 3) and BLCO-800 mg/kg body weight only (group 4) for 7 d. Protein levels of caspase 3, FasL, NF-kB, steroidogenic acute regulatory protein and stress response proteins were determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Immunofluorescence staining was used to quantify the expression of caspase 3, FasL and NF-kB. Apoptosis was quantified by the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay. Administration of BLCO resulted in a significant increase in the levels of stress response proteins and apoptosis-related proteins by 50% and above after 7 d following BLCO exposure and a concomitant increase in expression of caspase 3, FasL and NF-kB expression by immunofluorescence staining. Apoptosis showed a significant increase in TUNEL positive cells. Co-administration with quercetin or vitamin E reversed BLCO-induced apoptosis and levels of stress protein, relative to control. These findings suggest that quercetin and vitamin E may confer protection against BLCO-induced testicular oxidative stress-related apoptosis.

Neuroprotective, antiapoptotic and antioxidant effects of l-carnitine against caffeine-induced neurotoxicity in SH-SY5Y neuroblastoma cell line

Context: Caffeine is the most widely consumed nervous stimulant that induces oxidative-mediated apoptosis and cell cycle arrest in neural cells. Due to low toxicity, high accumulation in neural cells, reduction of the free fatty acids and antioxidant property, l-carnitine (LC) is an interesting compound to be used in vivo against several neuropathies. Objectives: This study was conducted to evaluate the protective effect of LC against caffeine-induced cytotoxicity in SH-SY5Y neuroblastoma cell line. Materials and methods: SH-SY5Y neuroblastoma cells were incubated with cytotoxic doses of caffeine (5 and 10 mM) in the presence or absence of LC (1 and 5 mM) for duration of 18–24 h. The antioxidant factors, DNA fragmentation and cytotoxic markers were assessed in treated cells. Results: Our results showed that 5 mM LC for 18 h protected SH-SY5Y cells against cytotoxicity induced by both doses of caffeine. This protection was related to the inhibition of reactive oxygen species generation, the increase in the superoxide dismutase and catalase activities and glutathione content and the prevention of lipid peroxidation in cultured SH-SY5Y cells. Apoptosis markers such as DNA fragmentation and caspase-3 activity were also inhibited by 5 mM LC in caffeine-treated cells. Discussion and conclusion: Our results suggest that LC could protect SH-SY5Y cells from caffeine-induced injury through the inhibition of oxidative damage, mitochondria dysfunction and inhibition of cell apoptosis. Our results indicate that LC therapy may be a valuable approach for the suppression of oxidative stress-related apoptosis in various neural diseases.

Pretreatment with low dose etomidate prevents etomidate-induced rat adrenal insufficiency by regulating oxidative stress-related MAPKs and apoptosis

Etomidate is frequently used as an anesthetic and sedation agent in the clinic setting. This study determined that a low-dose pre-infusion followed by a continuous dose infusion of etomidate could reduce etomidate-induced adrenal gland insufficiency. Sixty adult male Wistar rats were used, with six rats per group. Based on preliminary experiments, 0.6mg/kg etomidate was selected as the low dose for this study. Oxidative stress and apoptosis-related proteins in the adrenal glands were assayed using Western blot, and serum levels of CORT and 11β-hydroxylase were detected using ELISA. Pretreatment with a single bolus of low dose etomidate significantly increased the levels of CORT and 11β-hydroxylase as well as the activities of superoxide dismutase (SOD), catalase (CAT) and glutathioneperoxidase (GPx) in the adrenal glands, but reduced nitric oxide (NO) production when compared to the positive group. Furthermore, Western blot data showed that pretreatment with low dose etomidate increased extracellular signal-regulated kinase1/2 (ERK1/2), CREB and bcl-2 activation, but suppressed the p-p38, c-JunN-terminal kinase (JNK), inducible NO synthase (iNOS), cleaved-caspase3, cleaved-poly-ADP-ribose polymerase (PARP), bax, and AKT activation. The ERK inhibitor PD98059 and the p38MAPK inhibitor SB203580 abolished the protective effect of low dose etomidate pretreatment. These data demonstrated that pretreatment with low dose etomidate attenuated etomidate-induced adrenal insufficiency to rat adrenal glands. Oxidative stress-related MAPKs and apoptosis proteins might be responsible for mediating the etomidate preconditioning effect in rats.