Anti-oxidative Stress Ability Research Articles

Bifidobacterium animalis A12 and Lactobacillus salivarius M18-6 Alleviate Alcohol Injury by keap1-Nrf2 Pathway and Thioredoxin System.

Excessive drinking can significantly damage people's health and well-being. Although some lactic acid bacterial strains have been previously shown to alleviate the symptoms of alcohol injury, the mechanism underlying these effects remains unclear. The aim of this study was to establish an alcohol injury model and examine the protective effect and mechanism of B. animalis A12 and L. salivarius M18-6. The results showed that A12 freeze-dried powder could maintain the survival rate of mice with alcohol injury at 100%. Compared with Alco group, L. salivarius M18-6 dead cell improved the survival rate of mice, attenuated liver steatosis, and significantly down-regulated serum Alanine transaminase (ALT) level; at the same time, it activated keap1-Nrf2 signaling pathway and up-regulated Superoxide dismutase (SOD), it protects mouse liver cells from oxidative stress induced by alcohol injury. In addition, B. animalis A12 can reduce the stress response to short-term alcohol intake and improve the ability of anti-oxidative stress by upregulating the level of isobutyric acid, reducing the level of keap1 protein in the liver of mice and upregulating the expression of thioredoxin genes (Txnrd1, Txnrd3, Txn1). Taken together, the results showed that B. animalis A12 and L. salivarius M18-6 alleviate alcohol injury in mice through keap1-Nrf2 signaling pathway and thioredoxin system.

Fisetin Ameliorates Diabetic Nephropathy-Induced Podocyte Injury by Modulating Nrf2/HO-1/GPX4 Signaling Pathway.

Diabetic nephropathy (DN) is one of the most severe microvascular complications of diabetes and has become the leading cause of end-stage renal disease formation. The pathogenesis of diabetic nephropathy is very complex and is still not fully understood. Fisetin is a flavonoid polyphenolic compound that is widely found in different fruits, vegetables, and medicinal plants. Many studies have indicated that it has a variety of pharmacological activities. In this study, we investigated the mechanism of action of fisetin in the protection of DN-induced podocyte injury both in vivo and in vitro. Results showed that fisetin could reduce high glucose (HG)-induced podocyte injury and streptozotocin (STZ)-induced diabetic nephropathy in mice. According to the histopathological staining results, fisetin ameliorated DN-induced glomerular injury in a dose-dependent manner. Western blot and immunofluorescence results showed that fisetin effectively promoted the expression of podocyte functional integrity marker proteins and inhibited the expression of podocyte injury marker proteins. In addition, according to the Western blot and RT-qPCR results, fisetin activates the nuclear translocation of Nrf2 to exert antioxidative stress ability and affects the expression of downstream antioxidant enzymes HO-1, GPX4, and other ferroptosis-related markers, thereby protecting against HG-induced podocyte ferroptosis and oxidative stress injury in DN mice. In summary, this study demonstrated that fisetin could enhance the antioxidative stress capacity of DN mice by promoting the activation of the Nrf2/HO-1/GPX4 signaling pathway in renal tissues, and attenuated HG-induced podocytes injury and STZ-induced DN in mice.

The Aux/IAA protein TaIAA15-1A confers drought tolerance in Brachypodium by regulating abscisic acid signal pathway.

Overexpression of the Aux/IAA protein TaIAA15-1A from wheat improves drought tolerance by regulating the ABA signalling pathway in transgenic Brachypodium. Drought is a major abiotic stress that causes severe crop yield loss. Aux/IAA genes have been shown to be involved in drought stress responses. However, to the best of our knowledge, there has been little research on the molecular mechanism of the wheat Aux/IAA gene in the context of drought tolerance. In this study, we found that expression of the wheat Aux/IAA gene TaIAA15-1A was upregulated by PEG6000, NaCl, SA, JA, IAA and ABA. Transgenic plants overexpressing TaIAA15-1A showed higher drought tolerance than wild-type (WT) plants. The physiological analyses showed that the transgenic lines exhibited a higher survival rate, shoot length, and relative water content than the WT plants. The activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) were enhanced in transgenic lines, causing a reduction in the hydrogen peroxide (H2O2) and superoxide anion radical (O2-) contents. Transcriptome analysis showed that TaIAA15-1A overexpression alters the expression of these genes involved in the auxin signalling pathway, ABA signalling pathway, phenolamides and antioxidant pathways. The results of exogenous ABA treatment suggested that TaIAA15-1A overexpression increased sensitivity to ABA at the germination and postgermination stages compared to WT plants. These results indicate that TaIAA15-1A plays a positive role in plant drought tolerance by regulating ABA-related genes and improving antioxidative stress ability and has potential application in genetically modified crops.

Encapsulation of berberine decorated ZnO nano-colloids into injectable hydrogel using for diabetic wound healing.

Chronic wound healing in diabetic patients had been considered a major clinical challenge, so there was an urgent need to establish more effective treatment methods. In this study, we prepared berberine-modified ZnO nano-colloids hydrogel (ZnO-Ber/H) and evaluated its wound healing performance in a diabetic rat. The prepared ZnO-Ber/H had excellent moisturizing, anti-inflammatory and anti-oxidative stress abilities. In vitro, ZnO-Ber/H could effectively up-regulate antioxidant stress factors (Nrf2, HO-1, NQO1) by 4.65-fold, 2.49-fold, 2.56-fold, respectively. In vivo experiments have shown that ZnO-Ber/H could effectively improve the wound healing rate (92.9%) after 15 days of treatment. Meanwhile, the ability of anti-oxidative stress had also been verified in vivo. ZnO-Ber/H down-regulated inflammatory factor (TNF-α, IL-1β, and IL-6) by 72.8%, 55% and 71% respectively, up-regulated vascular related factors VEGF and CD31 by 3.9-fold and 3.2-fold by Western blot. At the same time, ZnO-Ber/H could promote the expression of EGFR and FGFR, thereby affecting the generation of new epithelial tissue. Based on extensive characterization and biological evaluation, ZnO-Ber/H was expected to be a potential candidate for promoting diabetic wound healing.

Pretreatment of nucleus pulposus mesenchymal stem cells with appropriate concentration of H2O2 enhances their ability to treat intervertebral disc degeneration

BackgroundNucleus pulposus mesenchymal stem cells (NPMSCs) transplantation is a promising treatment for intervertebral disc degeneration (IVDD). However, the transplanted NPMSCs exhibited weak cell proliferation, high cell apoptosis, and a low ability to resist the harsh microenvironment of the degenerated intervertebral disc. There is an urgent need to explore feasible methods to enhance the therapeutic efficacy of NPMSCs transplantation.ObjectiveTo identify the optimal concentration for NPMSCs pretreatment with hydrogen peroxide (H2O2) and explore the therapeutic efficacy of NPMSCs transplantation using H2O2 pretreatment in IVDD.MethodsRat NPMSCs were pretreated with different concentrations (range from 25 to 300 μM) of H2O2. The proliferation, reactive oxygen species (ROS) level, and apoptosis of NPMSCs were detected by cell counting kit-8 (CCK-8) assay, 5-ethynyl-2′-deoxyuridine (EdU) staining, and flow cytometry in vitro. The underlying signalling pathways were explored utilizing Western blotting. A rat needle puncture-stimulated IVDD model was established. X-ray, histological staining, and a multimode small animal live imaging system were used to evaluate the therapeutic effect of H2O2-pretreated NPMSCs in vivo.ResultsNPMSCs pretreated with 75 μM H2O2 demonstrated the strongest elevated cell proliferation by inhibiting the Hippo pathway (P < 0.01). Meanwhile, 75 μM H2O2-pretreated NPMSCs exhibited significantly enhanced antioxidative stress ability (P < 0.01), which is related to downregulated Brd4 and Keap1 and upregulated Nrf2. NPMSCs pretreated with 75 μM H2O2 also exhibited distinctly decreased apoptosis (P < 0.01). In vivo experiments verified that 75 μM H2O2-pretreated NPMSCs-transplanted rats exhibited an enhanced disc height index (DHI% = 90.00 ± 4.55, P < 0.01) and better histological morphology (histological score = 13.5 ± 0.5, P < 0.01), which means 75 μM H2O2-pretreated NPMSCs can better adapt to the environment of degenerative intervertebral discs and promote the repair of IVDD.ConclusionsPretreatment with 75 μM H2O2 was the optimal concentration to improve the proliferation, antioxidative stress, and antiapoptotic ability of transplanted NPMSCs, which is expected to provide a new feasible method to improve the stem cell therapy efficacy of IVDD.

The Therapeutic Effect of Coriolus versicolor Fruiting Body on STZ-Induced ICR Diabetic Mice.

Coriolus versicolor is a natural drugs which has many pharmacological effects such as antitumor and enhanced immune activity. This paper studies the therapeutic effect of Coriolus versicolor fruiting body (CVFB) on streptozotocin (STZ)-induced Institute of Cancer Research (ICR) diabetic mice, the STZ solution was administered intraperitoneally at a dose of 150 mg/kg after fasting the mice, and ICR mice with fasting blood glucose >16.7 mmol/l were selected for research. Metformin was the positive control, and the dose of CVFB powder (1000 mg/kg, 2000 mg/kg, and 4000 mg/kg) for 28 consecutive days by gavage. The serum and liver of mice were collected for relevant index content testing. The results showed that CVFB can control or reduce the fasting blood glucose of mice and accelerate the rate of glucose metabolism, can reduce the levels of total cholesterol (T-CHO), triglyceride (TG), and high-density lipoprotein cholesterol (HDL-C) in mice, and regulate the abnormal symptoms of blood lipid metabolism commonly found in diabetes. It can increase the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) antioxidant enzymes and enhance the ability of antioxidative stress in diabetic mice. In the H&E staining and apoptosis experiments of pancreatic tissue, CVFB can greatly reduce the inflammatory factors present in islets, increase the islet cells, and reduce the apoptotic rate caused by diabetes. All data confirmed the therapeutic effect of CVFB on diabetic ICR mice. The present study provides a scientific basis for the development of drugs for the prevention and treatment of diabetes, it is of great significance to the in-depth study of Coriolus versicolor.

The Effects of Lemon Balm (Melissa officinalis L.) Essential Oil on the Stress Response, Anti-Oxidative Ability, and Kidney Metabolism of Sea Bass during Live Transport.

Simple SummaryThe greatest challenge of long-distance live transport of fish is high mortality caused by stress and oxidative damages. In this study, the effects of lemon balm (Melissa officinalis L., MO) on the stress response of sea bass were evaluated. Sea bass were treated with different concentrations of MO (10, 20, 40 mg/L, respectively) and were transported for 72 h in transport boxes. The results of this study indicated that the level of cortisol, glucose, lactic acid, heat shock proteins, catalase, myeloperoxidase, glutathione peroxidase, uric acid, and urea nitrogen of samples treated with MO were lower than the control. The sample treated with 40 mg/L MO showed higher antioxidant capacity. In conclusion, the effect of MO on alleviating stress responses was similar to MS-222 and eugenol.This study was conducted to enhance the viability and alleviate the oxidative stress response using MO for sea bass during live transport. Six experimental groups were designed, and the effects of the physiological responses of MO were evaluated in comparison with MS-222 and eugenol. The physiological stress levels, proprotein convertase subtilisin/kexin type 9 (PCSK-9), antioxidant enzyme activities, and kidney parameters of blood serum were determined. It was found that cortisol level, glucose (Glu), lactic acid (LD), heat shock proteins (HSPs), catalase (CAT), myeloperoxidase (MPO), glutathione peroxidase (GSH-Px), uric acid (UA), and urea nitrogen (BUN) in the MO-treated samples were lower than that of the control (133.72 ng/L); however, the total antioxidant capacity (T-AOC) was higher after 72 h of the simulated live transport. The ability to resist oxidative stress increased along with the increase in the MO concentration in the water during live transport, which was similar to the results of MS-222 and eugenol treatment. In conclusion, MO, acting as a kind of novel sedative and anesthetic, can be used to improve the oxidative system and survival rate during live transport. The results of this study provide a reference for enhancing animal welfare and anti-oxidative stress ability, reducing mortality and the stress response during live fish transport.

Analysis of overwintering indexes of winter wheat in alpine regions and establishment of a cold resistance model

Wheat is the main food crop in the world. The planting of winter wheat in alpine regions can not only improve the land use efficiency, but also increase the income of farmers. The planting of winter wheat in alpine regions depends on whether it can survive the winter smoothly. Therefore, the study on the physiological process of winter wheat has application value.Over a three-year field experiment, the relationships between osmotic and anti-oxidative stress in tillering nodes and winter wheat overwintering capacity in alpine regions was examined. A multi-index cold-resistant overwintering capacity model of winter wheat was established using a (machine learning) logistic regression algorithm. The experiment included three winter wheat varieties (Dn1, Dn2, and J22) and eight key physiological indicators of cold resistance. The results showed that in terms of osmotic stress, the water content of tillering node was about 70%, and the Pro content was 2000-2500 μg g -1 , soluble sugar content of 1000 μg g -1 above is more conducive to winter wheat overwintering; In terms of antioxidant stress ability, all indexes were maintained at a high level, which worked together to maintain the stability of antioxidant system. Through the analysis of receiver operating characteristic (ROC) curve of cold resistance of each index, six indexes of tillering node water content, hardness, pro content, soluble sugar content, MDA content and POD activity were selected to establish the cold resistance model of winter wheat overwintering, and the effect of the model was evaluated by ROC curve.The winter wheat overwintering model established in this study can provide a convenient and quick method for evaluating the overwintering capacity of novel winter wheat varieties. • Wheat wintering in alpine regions in Heilongjiang Province. • Introduced tillering node hardness index to winter wheat overwinter research. • Key physiological indicators of winter wheat overwinter examined in detail. • Osmotic stress dominates the winter wheat overwinter in alpine regions. • Established prediction model of winter wheat overwintering capacity.

Alfalfa saponins inhibit oxidative stress-induced cell apoptosis through the MAPK signaling pathway

ABSTRACT Background: Oxidative stress could seriously affect the growth performance of piglets. As natural extracts of Alfalfa (Medicago sativa), alfalfa saponins have been shown to function as antioxidants in piglets in vivo. However, few studies have investigated the effects and mechanism of alfalfa saponins against oxidative stress in piglet cells in vitro. In the current study, piglets’ small intestinal epithelial cell line (IPEC-J2) was explored to investigate the protective effects of alfalfa saponins on injured cells induced by H2O2. Methods: To investigate the effects and mechanism of alfalfa saponins against oxidative stress in piglet cells, the cell viability, activity of antioxidant enzymes, LDH and the amount of MDA were detected in H2O2-treated cells after the cells were pre-incubated with alfalfa saponins. The mechanism of alfalfa saponins against H2O2-induced oxidative cell damage was explored by detecting the expression of mitochondrial apoptosis-related proteins. Furthermore, the signaling pathway of alfalfa saponins in IPEC-J2 cells under oxidative stress was also investigated. Results: The results indicated that alfalfa saponins could rescue cell viability, elevate the activity of antioxidant enzymes and down-regulate the activity of LDH and the amount of MDA in H2O2-induced cells. Conclusion: Alfalfa saponins could inhibit oxidative stress-induced cell mitochondrial apoptosis through the MAPK signaling pathway, thereby providing a new method for improving antioxidant stress ability by means of nutritional regulation.

The skin-color is associated with its physiological state: A case study on a colorful variety, hybrid grouper (Epinephelus fuscoguttatus × Epinephelus lanceolatus)

The hybrid grouper (Epinephelus fuscoguttatus ♀ × Epinephelus lanceolatus ♂) named Hulong grouper is a vital species variety in the grouper farming industry. During the breeding process, the hybrid grouper gradually showed the skin color variation phenomenon, including normal (N), white (W), secondary color (SC), and yellow (Y). We utilized a comparative transcriptome analysis approach via high throughput sequencing in different skin color grouper groups to understand the underlying molecular mechanism. Quantitative RT-PCR validated 20 differentially expressed genes consistent with the RNA-seq trend, indicating that our sequencing results are stable and reliable. Four skin transcriptomes were compared pairwise. The results revealed that four immune response-related genes (tlr4, ddit4, gpcr, and hsd3b) were the common DEGs in the different groups suggesting that there were some relations between pigmentation variance and immune difference. Therefore, further analysis of SOD, CAT, complement C3 and C4, and other immune-related genes showed that the normal group's immune status and anti-oxidative stress ability are stronger than other skin color groups. Moreover, the KEGG pathway analysis results showed that some DEGs were associated with the MAPK signal pathway, so we compared the proteic level differences of erk1/2, p38mapk, and jnk1 among different skin-color groups. We found the MAPK is a potential pathway involved in fish skin color regulation and plays an essential role in physiological and biochemical processes. In addition, expression pattern analysis showed that the mRNA expression of most melanin synthesis-related genes have the highest level in normal color individuals, consistent with the section analysis. These results shed light on the regulatory mechanism of different skin colors transformation in hybrid Hulong grouper. Understanding fish skin color genetics will facilitate future molecular selection of the fish skin colors with high market values.

Feeding with poly(I:C) induced long-term immune responses against bacterial infection in turbot (Scophthalmus maximus)

Poly(I:C) is a kind of chemosynthetic double-stranded RNA (dsRNA) analogue which could act as TLR3 agonist and induce IFN production. It is widely applied in anti-virus treatment and immunoregulation, as well as vaccine adjuvant in farmed animals. However, whether poly(I:C) could activate innate immune response to defense against bacterial infection remains unclear. In this study, we established a feeding trial model with different dose of poly(I:C) in turbot larvae, then challenged with Edwardsiella piscicida after 3–7 weeks resting period. The results show that feeding turbot with poly(I:C) exhibited a stronger inflammatory response and antioxidant stress ability, and significantly elevated the survival rate within the decreased bacterial loads. Importantly, the bacterial infection-induced white feces in hindgut of turbot were significantly alleviated after poly(I:C) feeding, and this administration induced protection could last for about 7 weeks. Taken together, these findings indicate that feeding turbot with poly(I:C) could enhance a long-term intestinal mucosal immunity in response to bacterial infection, suggesting that poly(I:C) might be a promising immunostimulant in aquaculture.

RNA-seq identifies long non-coding RNAs as potential therapeutic targets for human corneal endothelial dysfunction under oxidative stress

Human corneal endothelial cells (CECs) have limited ability to regenerate in vivo. Oxidative stress has been proposed as one potential reason. Understanding the mechanism of oxidative stress-induced CEC dysfunction might provide novel targets for improving CEC regenerative capacity, and help develop non-surgical therapeutic strategies for CEC dysfunction. Long non-coding RNAs (lncRNAs) are non-coding transcripts with multiple biological functions. The roles of lncRNAs in ocular cells under oxidative stress have been widely studied, such as lens epithelial cells, trabecular meshwork cells, and retinal ganglion cells. In the current study, we established oxidative stress-induced CEC dysfunction model in vitro. By RNA sequencing technology, we identified 824 differentially expressed lncRNAs in CEC dysfunction group, including 667 upregulated lncRNAs and 157 downregulated lncRNAs. We finally demonstrated that CEC functions under oxidative stress, including cellular proliferation, apoptosis, and anti-oxidative stress ability, could be regulated by different lncRNAs, including lncRNA-Z93241.1, lncRNA-XLOC_000818, and lncRNA-AC007952.4. Targeting these lncRNAs might be useful to further elucidate the pathology of CEC dysfunction and develop novel therapeutic strategy.

Isoliquiritigenin alleviates LPS/ D-GalN-induced acute liver failure by activating the PGC-1α/ Nrf2 pathway to reduce oxidative stress and inflammatory response

Acute liver failure (ALF) is a dramatic liver disease characterized by large areas of inflammation. However, there are no available effective targeted drugs for ALF treatment. In the study, serum biochemical index and H&E were used to explore the amelioration of the liver histopathological changes. The oxidative stress kits, quantitative real-time PCR, western blot, immunohistochemistry, immunofluorescence staining, reactive oxygen species (ROS), and siRNA were used to elucidate the mechanisms underlying isoliquiritigenin (ISL) protection. The results showed that ISL significantly improved the liver pathological changes. Furthermore, ISL reduced oxidative stress by altering the expression of PGC-1α, Nrf2, HO-1, NQO1, Keap1, GCLC, and GCLM in damaged hepatocytes. Moreover, the levels of inflammation-related genes including NLRP3 inflammasome, IL-1β, IL-6, TNF-α, iNOS, and Mip-2 were repressed by ISL. In addition, ISL alleviated LPS/D-GalN-induced hepatocytes apoptosis by increasing the Bcl-2/Bax ratio and suppressing the expression of cleaved caspase-3. Further in vivo and in vitro evidence proved the involvement of the PGC-1α/Nrf2 signaling pathway in ISL protection. In conclusion, ISL improves the ability of anti-oxidative stress, alleviates inflammatory reaction, apoptosis, and inhibits NLRP3 inflammasome to protect lipopolysaccharide/D-galactosamine (LPS/D-GalN)-induced ALF through activating the PGC-1α/Nrf2 pathway, which provides the possibility for the treatment of ALF.

Biomimetic gold nanocages for overcoming chemoresistance of osteosarcoma by ferroptosis and immunogenic cell death

Chemoresistance remains a huge challenge for the treatment of osteosarcoma (OS). Multiple mechanisms are involved in chemoresistance of cisplatin. In our research, we found that Nrf2/xCT pathway contributes to the occurrence of chemoresistance of cisplatin in OS by enhancing the ability of antioxidative stress. Recently, oxidative stress defense and ferroptosis have attracted wildly attention in overcoming chemoresistance. Different from apoptosis, necroptosis, and autophagy, ferroptosis is a new programmed cell death pathway with the accumulation of reactive oxygen species (ROS). Synergistic treatment of ferroptosis and photothermal therapy (PTT) can perfectly overcome chemoresistance, and immunogenic cell death (ICD) induced by PTT can initiate effective anti-tumor immunity to suppress tumor growth and recurrence. Thus, we designed a cancer cell membrane coated gold nanocages loaded with RSL3 (C-R-AuNC) for the treatment of chemoresistance of OS. RSL3 induces ferroptotic cell death by the inhibition of glutathione peroxidase (GPX4). Gold nanocages coated with the cell membrane, as a nanocarrier, can achieve targeted drug delivery, controlled drug release, PTT, and induced ICD. In our researches, excellent outcomes for the treatment of chemoresistance of OS were achieved by C-R-AuNC, which is believed to serve as a promising strategy for clinic treatment of drug-resistant OS in future.

Lycium barbarum polysaccharides attenuate cardiovascular oxidative stress injury by enhancing the Keap1/Nrf2 signaling pathway in exhaustive exercise rats.

Moderate exercise is beneficial to physical and mental health. When the amount of exercise and exercise intensity exceeds a certain limit and reaches the state of exhaustion, oxidative stress levels in the body increase, which can lead to oxidative stress‑associated damage. Lycium barbarum polysaccharide(LBP) is one of the primary active ingredients extracted from wolfberry. Following exhausting exercise in rats, LBP supplements decrease damage to the myocardium and blood vessels, indicating that LBP exerts a protective effect on the cardiovascular system. The Kelch‑like ECH‑associated protein1(Keap1)/NF‑E2‑related factor2(Nrf2) anti‑oxidative stress signaling pathway improves total oxidizing ability; anti‑apoptosis and other aspects serve a vital role. In the present study, LBP intervention was performed invivo and invitro to observe its effect on the Keap1/Nrf2 pathway and oxidative stress‑associated indicators in order to clarify its protective mechanism. For the invivo experiments, 60male Sprague‑Dawley rats were randomly divided into normal control and aerobic, exhaustive and exhaustive exercise+LBP (200mg/kg/day) groups. For the invitro experiments, a rat thoracic aortic endothelial cell (RTAEC) oxidative stress model was established using angiotensinII (AngII) and divided into blank control, LBP (3,200µg/ml), AngII (1x10‑4 mol/l) and AngII+LBP groups. For invitro experiments, small interfering (si)RNA (50nmol) was used to transfect RTAEC and induce gene silencing of Nrf2. ELISA, hematoxylin and eosin staining, TUNEL, immunofluorescence, western blotting, immunohistochemistry and reverse transcription‑quantitative PCR were used to evaluate and verify the effect of LBP on oxidative stress indicators and the expression of Keap1/Nrf2 antioxidative stress signaling pathway. The invivo experiments showed that LBP decreased the expression of serum malondialdehyde (MDA) and AngII, as well as apoptosis of blood vessels and cardiomyocytes and expression of TNF‑α in rats following exhaustive exercise. Meanwhile, LBP enhanced expression of the Keap1/Nrf2 signaling pathway and downstream associated protein glutamyl‑cysteine synthetase catalytic subunit (GCLC), quinone oxidoreductase1(NQO1) and glutamate‑cysteine ligase modified subunit (GCLM) in the thoracic aorta and myocardium of rats following exhaustive exercise. In RTAEC invitro, LBP decreased the expression of MDA and TNF‑α in the supernatant, promoted the nuclear translocation of Nrf2 and increased expression levels of GCLC, NQO1 and GCLM. Following siNrf2 transfection into endothelial cells, the anti‑inflammatory and antioxidant stress effects of LBP were decreased. LBP was found to enhance the expression of the Keap1/Nrf2 antioxidant stress signaling pathway in endothelial cells, decreasing oxidative stress and the inflammatory response. Moreover, LBP improved the antioxidant stress ability of endothelial cells and alleviated injury of myocardial vascular tissue, thereby protecting the cardiovascular system.

Stepwise assembly of functional proteins on Photo-activated TiO2 surfaces confers anti-oxidative stress ability and stealth effect to vascular stents

Vascular stents suffer from in-stent restenosis and late thrombosis, which are closely related to adverse foreign body responses and a pathological microenvironment of oxidative stress. To alleviate these problems, we constructed a biological stealth and anti-oxidative stress titanium dioxide (TiO2) vascular stent by the stepwise assembly of functional proteins. In vitro, a photo-activated TiO2 (TiO2-UV) surface with traces of aldehyde groups and superhydrophilicity was used to immobilize the few-layer catalase (approximately 85% surface occupancy) in low secondary structure denaturation and covalent binding (TiO2-UV-CAT). When implanted in vivo, the TiO2-UV-CAT surface unoccupied by catalase selectively immobilized autologous albumin in blood. Autologous albumin was more dominant in competitive adsorption with fibrinogen (FGN) on TiO2-UV-CAT than on TiO2-UNT-CAT (catalase adsorbed untreated TiO2). Based on the synergistic effect of autologous albumin and catalase, TiO2-UV-CAT inhibited fibrinogen-platelet-mediated coagulation, inflammation, oxidative stress, and proliferation of smooth muscle cells (SMCs), and protected endothelial cells (ECs) from free radical damage. In addition, the in vivo inflammatory response to bovine catalase as a heterologous protein on the TiO2-UV-CAT was eliminated. This might have been due to the low secondary structure denaturation of immobilized catalase and the cloaking effect of rat autologous albumin. Finally, TiO2 vascular stents modified with catalase and autologous albumin exhibited excellent biocompatibility in vivo. This stepwise assembly of enzyme and autologous albumin on the photo-activated TiO2 surface could be a feasible surface engineering strategy for vascular stents. The study findings could provide new ideas for tailoring the biological function and improving the biocompatibility of implantable devices.

Curcumin reverses doxorubicin resistance in colon cancer cells at the metabolic level

Doxorubicin (Dox) is commonly used for the treatment of malignant tumors, including colon cancer. However, the development of P-glycoprotein (P-gp)-mediated multidrug resistance (MDR) in tumor chemotherapy has seriously reduced the therapeutic efficacy of Dox. Natural product curcumin (Cur) was demonstrated to have a variety of pharmacological effects, such as anti-tumor, anti-oxidation and anti-aging activities. Here, we examined the MDR reversal capability of Cur in drug sensitive-(SW620) and resistant-(SW620/Ad300) colon cancer cells, and elucidated the underlying molecular mechanisms at the metabolic level. It was found that Cur reversed P-gp-mediated resistance in SW620/Ad300 cells by enhancing the Dox-induced cytotoxicity and apoptosis. Further mechanistic studies indicated that Cur inhibited the ATP-dependent transport activity of P-gp, thereby increasing the intra-celluar accumulation of Dox in drug-resistant cells. Metabolomics analysis based on UPLC-MS/MS showed that the MDR phenomenon in SW620/Ad300 cells was closely correlated with the upregulation of spermine and spermidine synthesis and D-glutamine metabolism. Cur significantly inhibited the biosynthesis of spermine and spermidine by decreasing the expression of ornithine decarboxylase (ODC) and suppressed D-glutamine metabolism, which in turn decreased the anti-oxidative stress ability and P-gp transport activity of SW620/Ad300 cells, eventually reversed MDR. These findings indicated the MDR reversal activity and the related mechanism of action of Cur, suggesting that Cur could be a promising MDR reversal agent for cancer treatment.

Astragaloside II Ameliorated Podocyte Injury and Mitochondrial Dysfunction in Streptozotocin-Induced Diabetic Rats.

Astragaloside II (AS II), a novel saponin purified from Astragalus membranes, has been reported to modulate the immune response, repair tissue injury, and prevent inflammatory response. However, the protective effects of AS II on podocyte injury in diabetic nephropathy (DN) have not been investigated yet. In this study, we aimed to investigate the beneficial effects of AS II on podocyte injury and mitochondrial dysfunction in DN. Diabetes was induced with streptozotocin (STZ) by intraperitoneal injection at 55 mg/kg in rats. Diabetic rats were randomly divided into four groups, namely, diabetic rats and diabetic rats treated with losartan (10 mg·kg−1·d−1) or AS II (3.2 and 6.4 mg·kg−1·d−1) for 9 weeks. Normal Sprague-Dawley rats were chosen as nondiabetic control group. Urinary albumin/creatinine ratio (ACR), biochemical parameters, renal histopathology and podocyte apoptosis, and morphological changes were evaluated. Expressions of mitochondrial dynamics-related and autophagy-related proteins, such as Mfn2, Fis1, P62, and LC3, as well as Nrf2, Keap1, PINK1, and Parkin, were examined by immunohistochemistry, western blot, and real-time PCR, respectively. Our results indicated that AS II ameliorated albuminuria, renal histopathology, and podocyte foot process effacement and podocyte apoptosis in diabetic rats. AS II also partially restored the renal expression of mitochondrial dynamics-related and autophagy-related proteins, including Mfn2, Fis1, P62, and LC3. AS II also increased the expression of PINK1 and Parkin associated with mitophagy in diabetic rats. Moreover, AS II facilitated antioxidative stress ability via increasing Nrf2 expression and decreasing Keap1 protein level. These results suggested that AS II ameliorated podocyte injury and mitochondrial dysfunction in diabetic rats partly through regulation of Nrf2 and PINK1 pathway. These important findings might provide an innovative therapeutic strategy for the treatment of DN.

Theaflavin 3, 3'-Digallate Delays Ovarian Aging by Improving Oocyte Quality and Regulating Granulosa Cell Function.

Ovarian aging refers to the gradual decline of ovarian function with increasing physiological age, manifested as decreased ovarian reserve, elevated aging-related markers, and reduced oocyte quality. With a declining female fertility and a growing aging population, it is urgent to delay ovarian aging to maintain fertility and improve the life quality of women. Theaflavin 3, 3′-digallate (TF3) is a naturally bioactive polyphenol compound extracted from black tea, and its antioxidant properties play an important role in maintaining human health and delaying aging; however, the effects of TF3 on female reproduction and ovarian function are not yet clear. Here, we show that TF3 can preserve primordial follicle pool, partially restore the estrous cycle, and increase the offspring number of aged mice. Meanwhile, TF3 gavage increased the number of oocytes retrieved, decreased the level of reactive oxygen species, increased the level of glutathione, and decreased the abnormal rate of oocyte spindle after ovulation induction. Moreover, TF3 inhibited human granulosa cell apoptosis and improved their antioxidative stress ability. High-throughput sequencing and small-molecule-targeted pharmacological prediction show that TF3 affects multiple pathways and gene expression levels, mainly involved in reproductive and developmental processes. It may also affect cellular function by targeting mTOR to regulate the autophagic pathway, thereby delaying the process of ovarian aging. This study shows that TF3 can be used as a potential dietary supplement to protect ovary function from aging and thereby improving the life quality of advanced-age women.

Vitamin D3 Protects Mice from Diquat-Induced Oxidative Stress through the NF-κB/Nrf2/HO-1 Signaling Pathway.

Vitamin D3, as an indispensable and fat-soluble micronutrient, plays an important role in the health of humans and animals. At present, studies are focusing on the calcium absorption and immunoregulation function of vitamin D3; this study was aimed at exploring the antioxidative stress ability of vitamin D3 on diquat-induced intestinal dysfunction of ICR mice and the underlying mechanism. The results showed that oral gavage of vitamin D3 daily significantly improved the body weight gain and immune organ index and significantly reverted the abnormal changes of ALT, AST, SOD, GSH-Px, T-AOC, and MDA in the serum and jejunum induced by diquat. The addition of vitamin D3 also significantly reduced the concentration of DAO, D-LA, and certain proinflammatory cytokines in serum. Moreover, vitamin D3 improved the pathological morphology of the duodenum, jejunum, colon, liver, and kidney tissues, and it also largely attenuated the degree of inflammatory infiltration of macrophages and cell apoptotic index of jejunal epithelial tissue induced by diquat. The results demonstrated that vitamin D3 significantly recovered the intestinal barrier injury by enhancing the expression of mucins and tight junction proteins in the jejunum. In addition, the results indicated that vitamin D3 could significantly reduce the phosphorylation level of NF-κB (p65) and enhance the expression of Nrf2 and HO-1 in the jejunum compared with the diquat-induced group. This study suggested that oral administration of vitamin D3 can protect mice against oxidative damage by inhibiting the phosphorylation level of NF-κB (p65) and activating Nrf2-related signaling pathways.