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1.
Excessive alcohol consumption is one of the most important causes of hepatic steatosis, which involves oxidative stress. In particular, increased oxidative stress has been strongly linked to stimulation of the expression of heme oxygenase-1 (HO-1). This study aimed to investigate whether HO-1 could alleviates alcoholic steatosis in rats. Male Wistar rats were randomly divided into 4 groups: 1) the control group, 2) the EtOH group, 3) the EtOH + ZnPP-IX group and 4) the EtOH + Hemin group. Liver histopathology was investigated in weeks 1 and 4 after the start of the treatment period. Alcohol treatment significantly increased the hepatic malondialdehyde (MDA) levels, an oxidative stress marker. In addition, it increased the triglyceride, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels in both weeks. Gross examination demonstrated a yellowish and slightly enlarged liver in the alcohol-treated rats. Hematoxylin and eosin (H&E) and Oil Red O staining indicated hepatic steatosis, which was characterized by diffuse, extensive fatty accumulation and discrete lipid droplets of variable size in hepatocytes of the alcohol-treated rats. Administration of the HO-1 inducer hemin resulted in upregulation of hepatic HO-1 gene expression, reduced the MDA, triglyceride, ALT and AST levels and alleviated alcoholic hepatic steatosis, whereas administration of the HO-1 inhibitor zinc protoporphyrin IX (ZnPP-IX) resulted in downregulation of hepatic HO-1 gene expression and could not alleviate alcoholic hepatic steatosis either week. In conclusion, HO-1 could alleviate alcoholic hepatic steatosis in male Wistar rats and may be useful in development of a new therapeutic approach.  相似文献   
2.
随着社会的进步,主题公园在中国大地上蓬勃发展,在取得了一定成就的同时也暴露出一些问题。作者介绍了主题公园的产生及主题公园的发展历程,分析了主题公园存在的主要问题,并提出了解决问题的对策,为主题公园的可持续发展提供了新的思路。  相似文献   
3.
Growth of mastitis pathogenic bacteria was measured in bovine whey samples by a turbidometric microtechnique. Whey from mastitis cows supported growth as compared with whey prepared from normal milk. Blood proteins leak into milk during mastitis. A study was undertaken to analyze which molecules from blood would promote bacterial growth in whey Fractions containing hemoglobin showed a distinct growth-promoting effect. An inadequate iron supply is one of the restricting growth factors for bacteria in milk. By utilizing heme-compounds the pathogens can by-pass the effect of antimicrobial iron-binding present in milk in the form of lactoferrin.  相似文献   
4.
选取120头28日龄断奶仔猪,随机分成4个处理组,即对照组和3个试验组,每组3个重复,每个重复10头。对照组饲喂基础日粮,试验1组、试验2组、试验3组分别饲喂基础日粮中血红素铁净添加量为27.5mg/kg、55.0mg/kg、85.0mg/kg的3种试验日粮,研究日粮中添加血红素铁对断奶仔猪的生长性能、血液指标(血红蛋白浓度、免疫球蛋白浓度)的影响。试验正试期14d。结果表明,血红素铁各添加量组均能够提高仔猪的生长性能,日粮中血红素铁添加量为55mg/kg时,仔猪平均日增重、饲料转化率较对照组分别提高12.02%和10.27%(P<0.05)。血红素铁对断奶仔猪有良好的促生长作用,也在一定程度上提高了仔猪血液中血红蛋白和IgG浓度。  相似文献   
5.
In the course of studies on bioactive metabolites from marine fungi, a new 10-membered lactone, named penicillinolide A (1) was isolated from the organic extract of Penicillium sp. SF-5292 as a potential anti-inflammatory compound. The structure of penicillinolide A (1) was mainly determined by analysis of NMR and MS data and Mosher’s method. Penicillinolide A (1) inhibited the production of NO and PGE2 due to inhibition of the expression of iNOS and COX-2. Penicillinolide A (1) also reduced TNF-α, IL-1β and IL-6 production, and these anti-inflammatory effects were shown to be correlated with the suppression of the phosphorylation and degradation of IκB-α, NF-κB nuclear translocation, and NF-κB DNA binding activity. In addition, using inhibitor tin protoporphyrin (SnPP), a competitive inhibitor of HO activity, it was verified that the inhibitory effects of compound 1 on the production of pro-inflammatory mediators and NF-κB DNA binding activity were partially associated with HO-1 expression through Nrf2 nuclear translocation.  相似文献   
6.
The growth of maize seedlings was stimulated by shoot‐applied 5‐aminolevulinic acid 2 days after treatment at 90 and 120 μmol L?1. The effects of 5‐aminolevulinic acid on the activity of nitrate reductase (EC 1.6.6.2) and nitrite reductase (EC 1.7.7.1) and the chlorophyll, ammonium, heme and total free amino acid content were investigated by using maize seedlings to clarify the involvement of nitrogen metabolism and heme synthesis in the growth stimulation. 5‐Aminolevulinic acid increased the level of nitrate reductase activity at 90 μmol L?1 and the ammonium and heme content at 90 and 120 μmol L?1 2 days after treatment. The total amino acid content increased by 90 and 150 μmol L?1 5‐aminolevulinic acid 2 and 3 days after treatment, respectively. However, no significant change was observed in the activity of nitrite reductase or the chlorophyll content after the 5‐aminolevulinic acid treatment. These results suggest that the enhancement of nitrogen metabolism by nitrate reductase activation is involved in the 5‐aminolevulinic acid‐induced stimulation of maize seedling growth. The activation of nitrate reductase might be related to an increase in the heme content following the 5‐aminolevulinic acid treatment.  相似文献   
7.
pH can be manipulated to alter the oxidative stability of fish-based foods during storage. X-ray diffraction was used to investigate the ability of reduced pH to cause structural changes in fish hemoglobins that lead to enhanced oxidative degradation. Decreasing pH from 8.0 to 6.3 and 5.7 created a large channel for solvent entry into the heme crevice of perch hemoglobin beta chains. The proton-induced opening of this channel occurred between site CD3 and the heme-6-propionate. Solvent entry into the heme crevice can enhance metHb formation and hemin loss, processes that accelerate lipid oxidation. Reduced pH also decreased the distance between Ile at E11 in one of the alpha chains and the ligand above the heme iron atom. This sterically displaces O2 and protonated O2 which increases metHb formation. These studies demonstrate that pH reduction causes structural changes in perch hemoglobin which increase oxidative degradation of the heme pigment.  相似文献   
8.
为了有效利用猪血资源,减少猪血的环境污染,采用超声波酶解法水解血红蛋白制备血红素,研究了超声波破胞技术对血红素提取效果的影响。以血红素提取率为考察指标,通过单因素试验和正交试验确定了最佳工艺条件即:血红素与水的体积比1∶7,超声功率300W,超声次数60次,间歇比2∶5,破胞后经过酶水解,得到血红素。在此工艺条件下测得血红素提取率为652.71μg/mL。  相似文献   
9.
血红素铁对断奶仔猪生长性能和血液指标的影响   总被引:1,自引:0,他引:1  
选取120头28日龄断奶仔猪,随机分成4个处理组,即1个对照组和3个试验组,每组3个重复,每个重复10头。对照组饲喂基础日粮,试验1、2、3组分别饲喂基础日粮中血红素铁净添加量为27.5、55.0、85.0 mg/kg的3种试验日粮,研究日粮中添加血红素铁对断奶仔猪的生长性能、血液指标(血红蛋白浓度、免疫球蛋白浓度)的影响。试验正试期13 d。结果表明,血红素铁各添加量组均能够提高仔猪的生长性能,日粮中血红素铁添加量为55 mg/kg时,仔猪平均日增重、饲料转化率较对照组分别提高12.02%和10.27%(P<0.05)。血红素铁对断奶仔猪有良好的促生长作用,也在一定程度上提高了仔猪血液中血红蛋白和IgG浓度。  相似文献   
10.
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