Search

Objective: To investigate the protective effect of astragaloside Ⅳ (AS- Ⅳ) on the lipopolysaccharide (LPS)-induced oxidative injury of osteoblasts precursor cells MC3T3-E1, and to clarify its related mechanism. Methods: The MC3T3-E1 cells in logarithmic growth phase were divided into control group, LPS group and different concentrations (10，25，50 and 100 mg·L-1) of AS- Ⅳ groups. CCK-8 method was used to detect the cell activities in various groups. The MC3T3-E1 cells in logarithmic growth phase were divided into control group, LPS group, AS- Ⅳ group, AS- Ⅳ +LY294002 ［phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt) signaling pathway inhibitor］group. Flow cytometry was used to detect the levels of reactive oxygen species (ROS) in the cells in various groups. The levels of malondialdehyde (MDA) and glutathione (GSH) and the activities of superoxide dismutase (SOD) in the cells in various groups were determined with the related kits. The expression levels of heme oxygenase (HO-1) mRNA in the cells in various groups were detected by real-time fluorescence quantitative PCR (RT-qPCR) method. Western blotting method was used to detect the expression levels of PI3K，phosphorylated Akt (p-Akt)，and nuclear factor-E2 related factor 2 (Nrf2)，B-cell lymphoma-2 (Bcl-2), and Bcl-2 associated X protein (Bax) in the cells in various groups. Results: The CCK-8 method results showed that compared with control group, the cell activity in LPS group was significantly decreased (P<0. 01)； compared with LPS group, the activities of cells in 50 and 100 mg·L-1 AS- Ⅳ groups were significantly increased (P<0. 01). Compared with control group, the ROS and MDA levels in the cells in LPS group were significantly increased (P<0. 01), while the SOD activity and GSH level were decreased (P<0. 01)； compared with LPS group, the ROS and MDA levels in the cells in AS- Ⅳ group were significantly decreased (P<0. 01), the SOD activity and GSH level were significantly increased (P< 0. 01)； compared with AS-Ⅳ group, the ROS and MDA levels in the cells in AS-Ⅳ +LY294002 group were significantly increased ( P<0. 01), the SOD activity and GSH level were significantly decreased ( P< 0. 01). Compared with control group, the expression level of HO-1 mRNA and the expression levels of p-Akt, Nrf2, HO-1, and Bcl-2 proteins in the cells in LPS group were significantly decreased (P<0. 01), while the expression level of Bax protein was significantly increased (P<0. 01)； compared with LPS group, the expression level of HO-1 mRNA and the expression levels of p-Akt, Nrf2, HO-1，and Bcl-2 proteins in the cells in AS- Ⅳ group were signicantly increased (P<0. 01), while the expression level of Bax protein was significantly decreased (P<0. 01)；compared with AS- Ⅳ group, the expression level of HO-1 mRNA and the expression levels of p-Akt，Nrf2 HO-1 and Bcl-2 proteins in the cells in AS- Ⅳ + LY294002 group were significantly decreased (P<0. 01)，and the expression level of Bax protein was significantly increased (P<0. 01). Conclusion：AS- Ⅳ can play protective effect on the LPS-induced osteoblast injury by mediating PI3K/Akt/Nrf2 signaling pathway. [ABSTRACT FROM AUTHOR]

Objective To explore the effect of ginsenoside Rb1 (gRb1) on oxidative damage of human umbilical vein endothelial cells (HUVECs) resulted from hydrogen peroxide (H2O2). Methods HUVECs were divided into control group, H2O2 group and gRb1 group. MTT assay was used to determine cell survival; annexin V-FITC/PI double staining was used to detect cell apoptosis; SOD1 activity was measured with xanthine oxidase method; MDA concentration was detected by thibatituric acid assay; protein expression of ICAM-1 and VCAM-1 was analysed by Western blot. Results Compared with control group, the apoptosis rate, MDA production and the protein level of ICAM-1 and VCAM-1 significantly increased, but the cell viability and SOD1 activity decreased. Compared with H2O2 group, gRb1 reversed the parameters mentioned above. Conclusions gRb1 can alleviate oxidative damage of HUVECs by reducing cell apoptosis, oxidative stress and protein expression of ICAM-1 and VCAM-1.

Objective To investigate the effect of melatonin on oxidative injury of rat carotid arteries after balloon injury. Methods Twenty male sprague-dawley rats were randomized into control, melatonin, smoking, and smoking plus melatonin. An established protocol of smoking was carried out. The carotid arteries were collected 7 days later. The average content of ROS was measured. And Western blot was used to detected the expression of NF-κB, MCP-1, VCAM-1 and ICAM-1. Results Smoking significantly induced the increase of ROS and the expression of NF-κB, MCP-1, VCAM-1 and ICAM-1 in rat carotid arteries. Moreover, cigarette smoke exposure inhibited the expression of eNOS. Melatonin minimized the effect resulted from smoking. Conclusions Melatonin may attenuate the the oxidative injury and the expression of inflammatory mediators in rat carotid arteries resulted from smoking.

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Exhaustive exercise is a vigorous physical activity performed by an organism beyond its physiological limits, and it causes a series of histological changes in the body. Myocardial exercise-induced oxidative stress injury means that the organism generates free radicals through oxidative stress signal pathway to damage myocardial cells under exhaustive exercise. OBJECTIVE: To explore the mechanism of oxidative stress injury in rat myocardium caused by one-time exhaustive exercise based on the protein kinase C (PKC)/ NOX pathway. METHODS: Thirty adult male Sprague-Dawley rats were randomly divided into a control group, an exhaustive exercise group, and an exhaustive exercise+drug group, with 10 rats in each group. The exhaustive exercise+drug group was injected with PKC inhibitor chelerythrine (5 mg/kg body weight) for 3 consecutive days. Rats in the two exercise groups exercised at a speed of 25 m/min on a 0° incline treadmill until exhaustion. Immediately after exercise, blood sample was collected from each rat, and then the rat’s left ventricle was removed for hematoxylin-eosin staining to observe the morphological changes of myocardial cells. Serum and myocardial malondialdehyde and myocardial reactive oxygen species levels were detected. The protein expressions of PKC, NOX2, NOX4 and 3-NT in rat myocardial tissue were determined by western blot. RESULTS AND CONCLUSION: The myocardial tissues in the exhaustive exercise and exhaustive exercise+drug groups were damaged, but the damage was significantly eased in the exhaustive exercise+drug group compared with the exhaustive exercise group. Compared with the control group, the reactive oxygen species level in the myocardial tissue of the exhaustive exercise group increased significantly (P < 0.05). Compared with the control group, the content of malondialdehyde in the myocardial tissues of the exhaustive exercise and exhaustive exercise+drug groups was significantly increased (P < 0.01), and the concentration of serum malondialdehyde in the exhaustive exercise group was significantly increased (P < 0.05). Compared with the control group, the expression levels of PKC, NOX2, NOX4 and 3-NT proteins in the myocardium of rats after exhaustive exercise were significantly increased (P < 0.01). Compared with the exhaustive exercise group, the expression levels of NOX2 and NOX4 in the myocardial tissue of rats significantly decreased in the exhaustive exercise+drug group (P < 0.01), and the expression of 3-NT significantly decreased (P < 0.05). Therefore, one-time exhaustive exercise can activate PKC and increase its protein expression in rat myocardial cells, which in turn induces an increase in the expression of NOX2 and NOX4 proteins in the myocardium, catalyzes the generation of large amounts of reactive oxygen species, and leads to the excessive production of peroxynitrite anions, thereby causing oxidative damage to the myocardium. [ABSTRACT FROM AUTHOR]

Engineered probiotics can serve as therapeutics based on their ability of produce recombinant immune-stimulating properties. In this study, we built the recombinant Bacillus subtilis WB800 expressing antimicrobial peptide KR32 (WB800-KR32) using genetic engineering methods and investigated its protective effects of nuclear factor-E2-related factor 2 (Nrf2)‍-Kelch-like ECH-associated protein 1 (Keap1) pathway activation in intestinal oxidative disturbance induced by enterotoxigenic Escherichia coli (ETEC) K88 in weaned piglets. Twenty-eight weaned piglets were randomly distributed into four treatment groups with seven replicates fed with a basal diet. The feed of the control group (CON) was infused with normal sterilized saline; meanwhile, the ETEC, ETEC+WB800, and ETEC+WB800-KR32 groups were orally administered normal sterilized saline, 5×10 10 CFU (CFU: colony forming units) WB800, and 5×10 10 CFU WB800-KR32, respectively, on Days 1‍‒‍14 and all infused with ETEC K88 1×10 10 CFU on Days 15‍‒‍17. The results showed that pretreatment with WB800-KR32 attenuated ETEC-induced intestinal disturbance, improved the mucosal activity of antioxidant enzyme (catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx)) and decreased the content of malondialdehyde (MDA). More importantly, WB800-KR32 downregulated genes involved in antioxidant defense (GPx and SOD1). Interestingly, WB800-KR32 upregulated the protein expression of Nrf2 and downregulated the protein expression of Keap1 in the ileum. WB800-KR32 markedly changed the richness estimators (Ace and Chao) of gut microbiota and increased the abundance of Eubacterium&#95;rectale&#95;ATCC&#95;33656 in the feces. The results suggested that WB800-KR32 may alleviate ETEC-induced intestinal oxidative injury through the Nrf2-Keap1 pathway, providing a new perspective for WB800-KR32 as potential therapeutics to regulate intestinal oxidative disturbance in ETEC K88 infection.

To screen the toxic polar fractions of Daphne genkwa, compare the toxicity of D. genkwa on crypts epithelial cells IEC-6 before and after vinegar processing, and preliminarily investigate the mechanism of D. genkwa vinegar processing on toxicity reducing. The proliferation of IEC-6 cells was observed by MTT. The levels of superoxide dismutase (SOD), malondialdehyde (MDA), glutathione (GSH), lactate dehydrogenase (LDH), as well as the enzyme activity of Na⁺-K⁺-ATPase and Ca²⁺-Mg²⁺-ATPase were determined in IEC-6 cells to evaluate the oxidative damages degree of IEC-6 cells. The apoptosis and cell cycle were analyzed by Flow Cytometry. The results showed that the dichloromethane extraction was the toxic polar fraction of D. genkwa, and after vinegar processing, the toxicity of dichloromethane fraction was significantly reduced ( P <0.01). As compared with the blank control group, the dichloromethane fraction of D. genkwa can obviously decrease the levels of SOD, Na⁺-K⁺-ATPase, Ca²⁺-Mg²⁺-ATPase ( P <0.01) and content of GSH, but increase the level of LDH and MDA in cell supernatant ( P <0.01). Besides, it obviously increased the early and late apoptotic rate of IEC-6 cells, obviously decreased the proportion of G₁stage cells, increased the ratio of S stage cells and M stage cells ( P <0.01). After vinegar processing, as compared with D. genkwa groups of various doses, it can significantly increase the levels of SOD, Na⁺-K⁺-ATPase, Ca²⁺-Mg²⁺-ATPase ( P <0.01) and content of GSH, decrease the level of LDH, MDA( P <0.01), significantly decrease the early and late apoptosis rate of IEC-6 cells ( P <0.01), increase the proportion of G₁stage cells, and decrease the ratio of S stage cells and M stage cells ( P <0.01). Vinegar processing can reduce the toxicity of dichloromethane fraction of D. genkwa, and its mechanism may be associated with improving the activity of antioxidant enzymes and permeability in IEC-6 cells, and decreasing the oxidative damage., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Chinese Pharmaceutical Association.)

Objective: To observe the effects of cadmium chloride on mitochondrial function and the expression of PGC-1α in HK-2 cells, and explore the possible role of cadmium chloride in the process of mitochondrial oxidative damage of HK-2 cells., Methods: HK-2 cells were exposed to 0, 10, 20, 30, 40, 50 and 60 μmol/L of CdCl&#95;2 respectively for 24 h in vitro. MTT assay was used to observe the viability of HK-2 cells. The mitochondrial ROS was detected by Mito SOXTMRed staining. Mitochondrial membrane potential was measured by JC-1 staining flow cytometry. The activity of respiratory chain complex III was determined by Multi-functional microplate reader and PGC-1α expression was detected by Western blot analysis., Results: Compared with control, CdCl&#95;2 treatment at 20 and 60 μmol/L for 24 h the survival rate of HK-2 cells was decreased from( 77. 60 ± 0. 82) % ( 41. 97 ± 1. 22) %( P < 0. 01). The activity ofrespiratory chain complex III was decreased in a concentration-dependent manner( P <0. 05), while the mitochondrial ROS production was increased at the same time( P <0. 05), the JC-1 monomers positive ratio by the percentage of the treated cells was 1. 51, 1. 58, 1. 71, 2. 41 3. 47 times higher than untreated control( P < 0. 01). In addition, the expression of PGC-1α was decreased at 24 h( P < 0. 05)., Conclusion: Cadmium chloride may inhibit the expression of PGC-1α and the activity of respiratory chain complex III, and by inducing the mitochondrial ROS production and reducing mitochondrial membrane potential, leading to the damage of HK-2 cells.