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51.
SUN Lei GUO Wei MA Peng-jun MA Sheng-chao DU Xing-chen ZHANG Ming-hao HAO Yin-ju JIANG Yi-deng 《园艺学报》2020,36(1):119-126
AIM: To explore the role of DNA methylation of microRNA-30a-5p(miR-30a-5p) promoter region in hepatic injury. METHODS: Four-week-old normal mice and cystathionine β-synthase (CBS) single gene knockout mice were used and divided into normal (CBS+/+, n=12) group and single gene knockout (CBS+/-, n=12) group, and the mice were fed with high methionine diet for 8 weeks. HL-7702 hepatic cells were routinely cultured in vitro and divided into control group, homocysteine (Hcy) group and Hcy+5-azacytidne (AZC) group. Serum Hcy, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were measured by automatic biochemical analyzer. The levels of ALT and AST in the cells culture medium were determined by the microplate method. Hepatic injury in the mice were observed with HE staining. Cell viability staining was used to measure the viability of hepatocytes. RT-qPCR was used to detect the expression of miR-30a-5p in the liver tissues and hepatocytes. The correlation between the expression of miR-30a-5p and serum ALT and AST levels was analyzed by Pearson correlation analysis. DNA methylation level of miR-30a-5p promoter region in the liver tissues and hepatocytes was detected by nested landing methylation-specific PCR (nMS-PCR). RESULTS: Compared with the CBS+/+ mice, the serum levels of Hcy, ALT and AST in the CBS+/- mice were significantly increased (P < 0.05). HE staining showed the hepatocyte swelling and nuclear fragmentation and dissolution. The expression level of miR-30a-5p in the liver tissues was decreased (P < 0.01). Besides, the expression level of miR-30a-5p in the mice was negatively correlated with serum ALT and AST levels (r2=0.4557, P=0.0003, r2=0.4626, P=0.0003), and the DNA methylation of miR-30a-5p promoter region was increased (P < 0.01). In the HL-7702 cells, compared with control group,the ALT and AST levels were increased in Hcy group (P < 0.05, P < 0.01), and the cell viability was remarkablely decreased. DNA methylation of miR-30a-5p promoter region was increased (P < 0.01), which decreased after treated the cells with AZC (P < 0.05), while the expression level of miR-30a-5p in the cells was increased (P < 0.05). CONCLUSION: Hypermethylation of miR-30a-5p promoter region may play an important role in hepatic injury. 相似文献
52.
AIM: To study the effects of apelin-13 on oxidative stress induced by high uric acid in 3T3-L1 adipocytes and its underlying mechanisms. METHODS: 3T3-L1 adipocytes were stimulated with uric acid at 10 mg/dL for 48 h. Some of the adipocytes were administered with 1 μmol/L apelin-13 in the presence of uric acid at 10 mg/dL. The adipocytes stimulated with 100 μmol/L H2O2 were served as positive controls. The intracellular reactive oxygen species (ROS) concentrations were detected by flow cytometry. The biochemical kits were used to measure the activities of superotide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT) and NADPH oxidase (NOX) activity, and the content of malondialdehyde (MDA) in the cell lysate and the supernatant. The mRNA levels of renin-angiotensin system (RAS) components, including angiotensinogen (AGT), angiotensin-converting enzyrne1 (ACE1), angiotensin II type 1 receptor (AT1R) and AT2R, as well as angiotensin II receptor -like 1 (APJ) were measured by real-time PCR. The concentrations of angiotensin II (AngⅡ) in the cell lysate and the supernatant were measured by ELISA. RESULTS: Adipocytes stimulated with uric acid at 10 mg/dL had lower activities of antioxidant enzymes (SOD, GSH-PX and CAT) and higher levels of NOX activity and MDA content (P < 0.05). Accordingly, the intracellular ROS levels were found to be dramatically increased. However, apelin-13 administration attenuated uric acid-induced oxidative stress in the 3T3-L1 adipocytes. Uric acid at 10 mg/dL upregulated the mRNA expression of local RAS, enhanced AngⅡ concentrations both in the cell lysate and the supernatant, and down-regulated the mRNA level of APJ in the adipocytes (P < 0.05). Conversely, apelin-13 partially reversed these parameters. CONCLUSION: Apelin-13 attenuates oxidative stress induced by uric acid, may be via down-regulation of local RAS expression in the 3T3-L1 adipocytes. 相似文献
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54.
黑甜糯玉米新品种黑甜糯639的选育 总被引:1,自引:0,他引:1
黑甜糯639是以糯玉米自交系HNF为母本,以甜玉米自交系D91为父本配制而成的黑甜糯玉米一代杂种。生育期为91 d(天),株高263 cm,穗位151 cm,雄穗主轴与分枝角度中等,一级分枝18~23个,果穗筒型,籽粒黑紫色,甜糯籽粒比例为1∶3,籽粒可溶性糖含量为12.5%,支链淀粉占总淀粉含量的98.1%,口感佳。高抗丝黑穗病、茎腐病、大斑病,抗穗腐病和矮花叶病,平均每667 m~2鲜穗产量900 kg左右。适宜在山西省鲜食糯玉米主产区种植。 相似文献
55.
优松58是以细胞质雄性不育系HZ-28为母本,以自交系HL-94为父本配制而成的早熟松散型花椰菜一代杂种。华北地区秋露地从定植至收获60 d(天)左右。株型半直立,生长势强,叶片椭圆形,深绿色,叶缘多波浪;花球半球形,白色,球面光滑,花梗绿,口感脆嫩、甜,品质优,单球质量1.0 kg左右。常规栽培平均每667 m~2产量2 000 kg以上,可适当密植,田间对霜霉病、黑腐病的抗性强于对照津松62,适合北京、天津、河北、河南、山东、安徽等地秋季露地栽培。 相似文献
56.
之豇618是以从四川引进的麻子豇豆为母本,以从辽宁引进的ZH优选株系为父本进行杂交,采用系统选育结合分子标记辅助抗枯萎病鉴定育成的中熟豇豆新品种。植株蔓生,花紫色,主侧蔓均可结荚,平均单株结荚14.4条;商品荚油绿色,条荚顺直,喙绿色,鼠尾少,平均荚长63.7 cm,单荚质量26.6 g,豆荚肉厚,粗纤维含量低,口感糯、微甜,可溶性糖含量为24.0 mg · g~(-1);对日照长短不敏感,中抗枯萎病和病毒病,早期产量与之豇106相当,总产量2 000 kg · (667 m~2)~(-1)左右,适宜在全国各地(除高寒地区外)种植。 相似文献
57.
桂牛5号是以自交系Ca1-5-1为母本,以自交系Ca1-3-8为父本配制而成的牛角椒一代杂种。中早熟,植株生长势较强,连续坐果能力强;果实长牛角形,果长25~30 cm,果肩宽3.5~4.0 cm,单果质量125 g左右;青熟果黄绿色,老熟果鲜红色,商品性好,微辣,果实干物质含量7.88%,VC含量1?530 mg · kg~(-1),辣椒素含量0.023%,宜鲜食,耐贮运;田间对病毒病、炭疽病、疫病的抗性强于对照黄美龙,露地栽培鲜椒产量3?500 kg · (667 m~2)~(-1)左右,适宜广西、广东等地春、秋露地种植。 相似文献
58.
59.
云豌1号是以食荚90-17(无须蔓生品种)为母本,以食荚大菜豌(矮生品种)为父本进行杂交,经系统选育而成的矮生无须菜用豌豆新品种。植株直立矮生,株高50~60 cm,复叶无须(即卷须退化),营养体发达,叶片肥厚,嫩梢纤维少,幼苗质地柔软,食用品质佳,VC含量34.9 mg · kg~(-1),总黄酮含量3?290 mg · kg~(-1)。一般每667 m~2可产嫩尖850~1?200 kg,适宜云南省海拔1?100~2?400 m的豌豆产区或南方生境相似的秋播豌豆产区种植。 相似文献
60.
不同丝瓜品种褐变相关基因的表达分析 总被引:1,自引:0,他引:1
以7种不同丝瓜品种为试验材料,对采后丝瓜果实进行褐变鉴定,测定多酚氧化酶(PPO)活性、过氧化物酶(POD)活性及相关基因的表达量。结果表明:"苏丝3号""苏丝6号""苏丝7号"属于抗褐变品种;"苏丝4号""苏丝5号""苏丝10号"属于耐褐变品种;"苏丝8号"属于严重褐变。从褐变酶POD和PPO变化来看,"苏丝8号"POD活性高达456.7 U·mg-1,抗褐变品种"苏丝3号""苏丝6号""苏丝7号"POD活性均在250 U·mg-1。"苏丝8号"PPO活性为68.2 U·mg-1,"苏丝3号"PPO活性最小,低至25.2 U·mg-1。从褐变基因的变化来看,"苏丝8号"在LcPOD家族基因表达中均高于对照"苏丝3号",其中LcPOD3基因表达量高达5.23,是对照的5倍以上,其它的丝瓜品种LcPOD3基因变化不显著。褐变品种"苏丝8号"在LcPPO基因家族中上调显著,表明"苏丝8号"果实褐变时促进LcPPO基因家族的表达,从而转录翻译成PPO加快果实的褐变。与对照相比,丝瓜褐变基因LCWRKY在"苏丝8号"中上调显著,表明其参与了丝瓜果实采后褐变。其它丝瓜品种LCWRKY上调不显著。 相似文献