This article aims to study the effects of exogenous 24-epibrassinolide （EBR） on the changes in ROS, activities of antioxidative enzymes and antioxidants in cucumber （Cucumis sativus L.） seedling roots under hypoxi...This article aims to study the effects of exogenous 24-epibrassinolide （EBR） on the changes in ROS, activities of antioxidative enzymes and antioxidants in cucumber （Cucumis sativus L.） seedling roots under hypoxia stress. Seedlings of a hypoxiaresistant cultivar, Lühachun 4, and a hypoxia-sensitive cultivar, Zhongnong 8, were hydroponically grown for 8 d in normoxic or hypoxic nutrient solutions that were added or not added with 10^-3 mg L^-1 EBR. Under hypoxia stress, the ROS levels and the lipid peroxidation were significantly increased in the roots upon exposure to hypoxia stress, which were inhibited by EBR application. The EBR treatment significantly increased the seedlings growth and SOD, APX, GR activities, and contents of AsA and GSH under hypoxia stress. From the results obtained in this study, it can be concluded that oxidative damage on seedling roots by hypoxia stress can be considerably alleviated and the tolerance of plants was elevated.展开更多
High grain-Cd-accumulating rice variety Yongyou 9 was planted in Cd-contaminated farmland in Taizhou City, Zhejiang Province, China to study the effects of 5-aminolevulinic acid(ALA) and24-epibrassinolide(EBR) on Cd a...High grain-Cd-accumulating rice variety Yongyou 9 was planted in Cd-contaminated farmland in Taizhou City, Zhejiang Province, China to study the effects of 5-aminolevulinic acid(ALA) and24-epibrassinolide(EBR) on Cd accumulation in brown rice. Results showed that the exogenous ALA and EBR had no significant effects on agronomic traits, soil pH and total Cd content in soil, but had some effects on the available Cd content in soil, and significantly influenced the Cd accumulation in the different parts of rice. Results also showed that 100 mg/L exogenous ALA significantly reduced the Cd accumulation in brown rice to blow the food safety standard(0.2 mg/kg), and also significantly reduced the Cd contents in the roots and culm of rice. However, 200 mg/L exogenous ALA treatment increased the Cd content in brown rice remarkably. In addition, 0.15 mg/L EBR treatment increased Cd accumulation in roots, culm, leaves and brown rice notably, whereas 0.30 mg/L exogenous EBR treatment reduced the Cd accumulation in brown rice properly, but it was not significant. Therefore,proper concentration of ALA can effectively reduce the Cd accumulation in brown rice, which can be used as an effective technical method for the safe production of rice in Cd polluted farmland.展开更多
In this work we compared the effect of the growth regulator content of the culture medium on the growth of in vitro shoot tips of five yam accessions belonging to four yam species (one Dioscorea alata, one D. rotundat...In this work we compared the effect of the growth regulator content of the culture medium on the growth of in vitro shoot tips of five yam accessions belonging to four yam species (one Dioscorea alata, one D. rotundata, one D. cayenensis and two D. trifida). Medium S contained 0.6 μM benzyl adenine, 1.07 μM naphthalene acetic acid and 0.23 μM gibberellic acid while medium EBR contained 0.23 μM gibberellic acid and 0.1 μM 24-epibrassinolide. After 2 months of culture, oxidation level was significantly reduced on medium EBR compared to medium S for four of the five accessions tested. By contrast, medium EBR did not have any positive effect on shoot length since length of shoots produced after 2 months of culture on medium S and EBR were similar, except with accession 3-45T, for which shoot length was shorter on medium S compared to medium EBR. These results underline the potential of 24-epibrassinolide to reduce oxidation phenomena during in vitro culture and call for its utilization for regeneration of cryopreserved yam shoot tips, which is often impeded by oxidation phenomena.展开更多
The effect of 24-epibrassinolide on growth of pigeon pea [Cajanus cajan (L.) Millsp.] under aluminium toxicity was studied. 24-EBL reduced the impact of Al stress on plant growth. Particularly 24-EBL reduced the inhib...The effect of 24-epibrassinolide on growth of pigeon pea [Cajanus cajan (L.) Millsp.] under aluminium toxicity was studied. 24-EBL reduced the impact of Al stress on plant growth. Particularly 24-EBL reduced the inhibitory impact of aluminium toxicity on root growth which was further manifested in overall improvement of vegetative growth. Application of 24-epibrassinolide removed the inhibitory influence of Al nodulation. The growth stimulation in Cajanus plants by 24-EBL under Al stress was associated with elevated levels of chlorophylls, nucleic acids and soluble proteins. 24-Epibrassinolide application enhanced proline content in Al<sup>3+</sup> stressed Cajanus plants. Further, the supplementation of 24-epibrassinolide to Al stress treatments increased the activities of antioxidative enzymes viz., catalase [EC 1.11.1.6];peroxidase [EC 1.11.1.7];superoxide dismutase [EC 1.15.1.1] and ascorbate peroxidase [EC 1.11.1.11]. Lipid peroxidation induced by Al was found reduced with the supplementation of 24-epibrassinolide. The present studies demonstrated the ameliorating capability of 24-epibrassinolide on the Al induced inhibition of plant growth of C. cajan.展开更多
目的:探讨缺氧对脑内胆固醇代谢稳态及神经元衰老的影响。方法:8~12周龄的C57BL/6野生型雄性小鼠随机分为常氧(Normoxia)组和缺氧(Hypoxia)组;以缺氧处理小鼠海马神经元HT22细胞并分为对照(Control)组和缺氧(Hypoxia)组;以10µmol/...目的:探讨缺氧对脑内胆固醇代谢稳态及神经元衰老的影响。方法:8~12周龄的C57BL/6野生型雄性小鼠随机分为常氧(Normoxia)组和缺氧(Hypoxia)组;以缺氧处理小鼠海马神经元HT22细胞并分为对照(Control)组和缺氧(Hypoxia)组;以10µmol/L剂量的24-羟基胆固醇(24S-Hydroxycholesterol,24S-OHC)处理HT22细胞并分为Control组和24S-OHC组。苏木精-伊红染色(hematoxylin-ensin,HE)和尼氏(nissl)染色观察脑组织结构;酶联免疫吸附测定法(enzyme linked immunosorbent assay,ELISA)检测血清、脑组织和细胞24S-OHC水平;微量法检测脑组织和细胞总胆固醇(total cholesterol,TC)与甘油三酯(triglyceride,TG)水平;蛋白质免疫印迹(western blot,WB)法检测脑组织和细胞胆固醇代谢相关酶3-羟基-3-甲基戊二酰辅酶A还原酶(3-hydroxy-3-methylglutaryl-coenzyme A reductase,HMGCR)、细胞色素P450家族46亚家族A成员1(cytochrome P450 family 46 subfamily A member 1,CYP46A1)、衰老相关蛋白细胞周期蛋白依赖性激酶抑制因子2A(cyclin-dependent kinase inhibitor 2A,CDKN2A/p16)、细胞周期蛋白依赖性激酶抑制因子1A(cyclin-dependent kinase inhibitor 1A,CDKN1A/p21)、磷酸化组蛋白(phospho-H2AX,γH2AX)和脂质合成相关分子抗硬脂酰辅酶A去饱和酶1(stearoyl-Coenzyme A desaturase 1,SCD1)、脂肪酸合酶(fatty acid synthase,FASN)、固醇调节元件结合蛋白1c(sterol regulatory element-binding protein 1c,SREBP1c)的表达水平;免疫组织化学染色检测脑内CYP46A1和γH2AX的表达;检测各组小鼠大脑组织中基因表达谱,筛选目标差异表达基因(differentially expressed genes,DEGs),对DEGs进行基因本体(gene ontology,GO)和京都基因与基因组百科全书(Kyoto encyclopedia of genes and genomes,KEGG)富集分析;衰老相关β半乳糖苷酶(senescence-associatedβ-galactosidase,SA-β-Gal)染色评估细胞衰老情况;BODIPY染色观察细胞脂滴蓄积情况。结果:与常氧组比较,缺氧组脑湿重差异无统计学意义(P=0.573);Nissl染色显示存活神经元数目减少;血清24S-OHC水平升高,脑内24S-OHC和TG含量增多,TC含量减少(均P<0.05);胆固醇合成酶HMGCR表达降低,胆固醇分解酶CYP46A1表达升高,p16、p21和γH2AX表达增加(均P<0.05);转录组学结果显示,在GO分析中炎症通路与脂质相关通路富集,在KEGG分析中磷脂酰肌醇3-激酶/蛋白激酶B(phosphatidylinositol 3-kinase/protein kinase B,PI3K-Akt)信号通路和肿瘤蛋白p53(tumor protein 53,p53)信号通路等与衰老相关通路富集。缺氧处理HT22细胞实验中,与Control组相比,Hypoxia组细胞内TC含量减少,24S-OHC含量增多(均P<0.05);HMGCR表达降低,CYP46A1表达升高,p16、p21、γH2AX表达增加(均P<0.05);SA-β-gal阳性细胞明显增多。24S-OHC处理HT22细胞实验中,与Control组相比,24S-OHC组细胞内TC和TG含量均增多(均P<0.05);细胞内脂滴含量明显增多(P<0.05);HMGCR和CYP46A1表达降低,SCD1、FASN和SREBP1c表达升高,p16、p21和γH2AX表达升高(均P<0.05)。结论:慢性缺氧通过下调HMGCR和上调CYP46A1表达,诱导24S-OHC异常蓄积并触发SREBP1c/SCD1信号通路介导的脂毒性衰老。展开更多
恶性肿瘤严重威胁人类健康,其发病机制复杂多样。分化簇抗原(cluster of differentiation,CD)24是一种近年来备受关注的糖基化膜蛋白,其在人体正常组织中参与细胞生理功能调控、免疫稳态维持、组织发育与分化等生理过程,而在乳腺癌、卵...恶性肿瘤严重威胁人类健康,其发病机制复杂多样。分化簇抗原(cluster of differentiation,CD)24是一种近年来备受关注的糖基化膜蛋白,其在人体正常组织中参与细胞生理功能调控、免疫稳态维持、组织发育与分化等生理过程,而在乳腺癌、卵巢癌、肺癌等多种恶性肿瘤组织中呈现异常高表达。CD24为肿瘤干细胞(cancer stem cell,CSC)核心标志物,与肿瘤细胞的恶性生物学行为、肿瘤恶性进展、治疗耐受及不良预后密切相关。CD24可通过CD24/唾液酸结合免疫球蛋白样凝集素-10(sialic acid-binding immunoglobulin-like lectin-10,Siglec-10)通路抑制巨噬细胞吞噬、重塑肿瘤免疫抑制微环境、激活促癌信号通路、调控肿瘤细胞黏附转移等多重机制参与肿瘤发生和发展,且在血液肿瘤中表现出独特的功能双重性。系统探究CD24在不同恶性肿瘤中的表达特征、作用机制及预后价值,发现靶向CD24的单克隆抗体等治疗策略有良好的临床应用前景,且CD24相较经典免疫检查点具有低血液毒性的潜在优势。研究证实CD24可作为恶性肿瘤精准诊断、预后评估的潜在标志物及个体化治疗的新靶点,具有重要的基础研究意义与临床转化价值。展开更多
文摘This article aims to study the effects of exogenous 24-epibrassinolide （EBR） on the changes in ROS, activities of antioxidative enzymes and antioxidants in cucumber （Cucumis sativus L.） seedling roots under hypoxia stress. Seedlings of a hypoxiaresistant cultivar, Lühachun 4, and a hypoxia-sensitive cultivar, Zhongnong 8, were hydroponically grown for 8 d in normoxic or hypoxic nutrient solutions that were added or not added with 10^-3 mg L^-1 EBR. Under hypoxia stress, the ROS levels and the lipid peroxidation were significantly increased in the roots upon exposure to hypoxia stress, which were inhibited by EBR application. The EBR treatment significantly increased the seedlings growth and SOD, APX, GR activities, and contents of AsA and GSH under hypoxia stress. From the results obtained in this study, it can be concluded that oxidative damage on seedling roots by hypoxia stress can be considerably alleviated and the tolerance of plants was elevated.
基金supported by the Natural Science Foundation of Zhejiang Province,China(Grant No.LY17C020005)the Key Research and Development Project of Zhejiang Province,China(Grant No.2015C03020-4)+2 种基金the National Nature Science Foundation of China(Grant No.31401356)Jinhua Science and Technology Project(Grant No.2015-2-012)the National Training Program for College Students to Innovate and Start Enterprise(Grant No.201710356013)
文摘High grain-Cd-accumulating rice variety Yongyou 9 was planted in Cd-contaminated farmland in Taizhou City, Zhejiang Province, China to study the effects of 5-aminolevulinic acid(ALA) and24-epibrassinolide(EBR) on Cd accumulation in brown rice. Results showed that the exogenous ALA and EBR had no significant effects on agronomic traits, soil pH and total Cd content in soil, but had some effects on the available Cd content in soil, and significantly influenced the Cd accumulation in the different parts of rice. Results also showed that 100 mg/L exogenous ALA significantly reduced the Cd accumulation in brown rice to blow the food safety standard(0.2 mg/kg), and also significantly reduced the Cd contents in the roots and culm of rice. However, 200 mg/L exogenous ALA treatment increased the Cd content in brown rice remarkably. In addition, 0.15 mg/L EBR treatment increased Cd accumulation in roots, culm, leaves and brown rice notably, whereas 0.30 mg/L exogenous EBR treatment reduced the Cd accumulation in brown rice properly, but it was not significant. Therefore,proper concentration of ALA can effectively reduce the Cd accumulation in brown rice, which can be used as an effective technical method for the safe production of rice in Cd polluted farmland.
文摘In this work we compared the effect of the growth regulator content of the culture medium on the growth of in vitro shoot tips of five yam accessions belonging to four yam species (one Dioscorea alata, one D. rotundata, one D. cayenensis and two D. trifida). Medium S contained 0.6 μM benzyl adenine, 1.07 μM naphthalene acetic acid and 0.23 μM gibberellic acid while medium EBR contained 0.23 μM gibberellic acid and 0.1 μM 24-epibrassinolide. After 2 months of culture, oxidation level was significantly reduced on medium EBR compared to medium S for four of the five accessions tested. By contrast, medium EBR did not have any positive effect on shoot length since length of shoots produced after 2 months of culture on medium S and EBR were similar, except with accession 3-45T, for which shoot length was shorter on medium S compared to medium EBR. These results underline the potential of 24-epibrassinolide to reduce oxidation phenomena during in vitro culture and call for its utilization for regeneration of cryopreserved yam shoot tips, which is often impeded by oxidation phenomena.
文摘The effect of 24-epibrassinolide on growth of pigeon pea [Cajanus cajan (L.) Millsp.] under aluminium toxicity was studied. 24-EBL reduced the impact of Al stress on plant growth. Particularly 24-EBL reduced the inhibitory impact of aluminium toxicity on root growth which was further manifested in overall improvement of vegetative growth. Application of 24-epibrassinolide removed the inhibitory influence of Al nodulation. The growth stimulation in Cajanus plants by 24-EBL under Al stress was associated with elevated levels of chlorophylls, nucleic acids and soluble proteins. 24-Epibrassinolide application enhanced proline content in Al<sup>3+</sup> stressed Cajanus plants. Further, the supplementation of 24-epibrassinolide to Al stress treatments increased the activities of antioxidative enzymes viz., catalase [EC 1.11.1.6];peroxidase [EC 1.11.1.7];superoxide dismutase [EC 1.15.1.1] and ascorbate peroxidase [EC 1.11.1.11]. Lipid peroxidation induced by Al was found reduced with the supplementation of 24-epibrassinolide. The present studies demonstrated the ameliorating capability of 24-epibrassinolide on the Al induced inhibition of plant growth of C. cajan.
文摘目的:探讨缺氧对脑内胆固醇代谢稳态及神经元衰老的影响。方法:8~12周龄的C57BL/6野生型雄性小鼠随机分为常氧(Normoxia)组和缺氧(Hypoxia)组;以缺氧处理小鼠海马神经元HT22细胞并分为对照(Control)组和缺氧(Hypoxia)组;以10µmol/L剂量的24-羟基胆固醇(24S-Hydroxycholesterol,24S-OHC)处理HT22细胞并分为Control组和24S-OHC组。苏木精-伊红染色(hematoxylin-ensin,HE)和尼氏(nissl)染色观察脑组织结构;酶联免疫吸附测定法(enzyme linked immunosorbent assay,ELISA)检测血清、脑组织和细胞24S-OHC水平;微量法检测脑组织和细胞总胆固醇(total cholesterol,TC)与甘油三酯(triglyceride,TG)水平;蛋白质免疫印迹(western blot,WB)法检测脑组织和细胞胆固醇代谢相关酶3-羟基-3-甲基戊二酰辅酶A还原酶(3-hydroxy-3-methylglutaryl-coenzyme A reductase,HMGCR)、细胞色素P450家族46亚家族A成员1(cytochrome P450 family 46 subfamily A member 1,CYP46A1)、衰老相关蛋白细胞周期蛋白依赖性激酶抑制因子2A(cyclin-dependent kinase inhibitor 2A,CDKN2A/p16)、细胞周期蛋白依赖性激酶抑制因子1A(cyclin-dependent kinase inhibitor 1A,CDKN1A/p21)、磷酸化组蛋白(phospho-H2AX,γH2AX)和脂质合成相关分子抗硬脂酰辅酶A去饱和酶1(stearoyl-Coenzyme A desaturase 1,SCD1)、脂肪酸合酶(fatty acid synthase,FASN)、固醇调节元件结合蛋白1c(sterol regulatory element-binding protein 1c,SREBP1c)的表达水平;免疫组织化学染色检测脑内CYP46A1和γH2AX的表达;检测各组小鼠大脑组织中基因表达谱,筛选目标差异表达基因(differentially expressed genes,DEGs),对DEGs进行基因本体(gene ontology,GO)和京都基因与基因组百科全书(Kyoto encyclopedia of genes and genomes,KEGG)富集分析;衰老相关β半乳糖苷酶(senescence-associatedβ-galactosidase,SA-β-Gal)染色评估细胞衰老情况;BODIPY染色观察细胞脂滴蓄积情况。结果:与常氧组比较,缺氧组脑湿重差异无统计学意义(P=0.573);Nissl染色显示存活神经元数目减少;血清24S-OHC水平升高,脑内24S-OHC和TG含量增多,TC含量减少(均P<0.05);胆固醇合成酶HMGCR表达降低,胆固醇分解酶CYP46A1表达升高,p16、p21和γH2AX表达增加(均P<0.05);转录组学结果显示,在GO分析中炎症通路与脂质相关通路富集,在KEGG分析中磷脂酰肌醇3-激酶/蛋白激酶B(phosphatidylinositol 3-kinase/protein kinase B,PI3K-Akt)信号通路和肿瘤蛋白p53(tumor protein 53,p53)信号通路等与衰老相关通路富集。缺氧处理HT22细胞实验中,与Control组相比,Hypoxia组细胞内TC含量减少,24S-OHC含量增多(均P<0.05);HMGCR表达降低,CYP46A1表达升高,p16、p21、γH2AX表达增加(均P<0.05);SA-β-gal阳性细胞明显增多。24S-OHC处理HT22细胞实验中,与Control组相比,24S-OHC组细胞内TC和TG含量均增多(均P<0.05);细胞内脂滴含量明显增多(P<0.05);HMGCR和CYP46A1表达降低,SCD1、FASN和SREBP1c表达升高,p16、p21和γH2AX表达升高(均P<0.05)。结论:慢性缺氧通过下调HMGCR和上调CYP46A1表达,诱导24S-OHC异常蓄积并触发SREBP1c/SCD1信号通路介导的脂毒性衰老。
