Expression of cytochrome P4502E1 gene in hepatocellular carcinoma

AIM: To investigate cytpchrome P4502E1 (CYP2E1) geneexpression in occurrence and progression of hepatocellularcarcinoma (HCC).METHODS: The human liver arrayed library was spottedonto the nylon membranes to make cDNA array.Hybridizationof cDNA array was performed with labeled probes synthesizedfrom RNA isolated from HCC and adjacent liver tissues.Sprague-Dawley rats were administrated diethylnitrosamine(DENA) to induce HCC.CYP2E1 expression was detected bythe method of RT-PCR and Northern blot analysis.RESULTS: CYP2E1 was found by cDNA array hybridizationto express differently between HCC and liver tissues.CYP2E1only expressed in liver,but did not express in HCC tissuesand expressed lowly in cirrhotic tissues.In the progressionof cirrhosis and HCC,the expression level of CYP2E1 wasgradually decreased and hardly detected until the late stageof HCC.CONCLUSION: Using arrayed library to make cDNA arraysis an effective method to find differential expression genes.CYP2E1 is a unique gene expressing in liver but did notexpress in HCC.CYP2E1 expression descended along withthe initiation and progression of HCC,which is noteworthyfurther investigations in its significance in the developmentof HCC.     

前列腺素E1与心力衰竭

前列腺素E1(PGE1)是一种具有广泛生物活性的扩血管物质 ,在 1982年德国Schwarz公司作为药物首次上市后至今 ,已在心脑血管疾病、肢体血管疾病、肝炎、胰腺炎、外科手术、性疾病、成人呼吸窘迫综合征等多种疾病的治疗中收到了良好的临床效果。本文主要对其在心力衰竭 (心衰 )治疗中的作用作一综述。1　PGE1的概述1.1　PGE1的发现　 1934年 ,纽约妇科医生Kurzok在精液中发现了一种极其活跃的物质 ,能引起子宫平滑肌的收缩 ,1936年 ,VonEuler提出这种物质是脂肪酸 ,推测可能产生于前列腺 ,因此命名为前列腺素 (PG) ,196 0年 ,Bergstrom…     

前列腺素E1治疗急性胰腺炎

前列腺素Ｅ１治疗急性胰腺炎张弘迟景宏齐齐哈尔铁路中心医院黑龙江省齐齐哈尔市１６１０００ＳｕｂｊｅｃｔｈｅａｄｉｎｇｓＡｌｐｒｏｓｔａｄｉｌ／ｔｈｅｒａｐｅｕｔｉｃｕｓｅＰａｎｃｒｅａｔｉｔｉｓ／ｄｒｕｇｔｈｅｒａｐｙＡｃｕｔｅｄｉｓｅａｓｅ主题...     

前列腺素E1治疗老年人心力衰竭

前列腺素Ｅ１治疗老年人心力衰竭高心慰李正良一、对象和方法１９９３年１月至１９９４年４月对６１例心力衰竭患者在卧床休息、限盐、使用强心剂和利尿剂等综合治疗基础上，分别用前列腺素Ｅ１（ＰＧＥ１）（治疗组）和酚妥拉明（对照组）进行治疗观察，冠心病诊断采用《...     

Pyruvate dehydrogenase E1α deficiency

Summary Pyruvate dehydrogenase (PDH) deficiency has long been recognized as the most common defined cause of primary lactic acidosis in infancy and early childhood. More recently, it has also been described in patients with subacute/chronic neurodegenerative disease without significant metabolic acidosis. The great majority of cases of PDH deficiency result from a genetic defect in the E1 subunit of the complex. PDH E1 deficiency is an X-linked inborn error of metabolism in which a high proportion of heterozygous females manifest the condition. In this review of 29 patients with PDH E1 deficiency, particular emphasis is given to those aspects of the disorder which are specifically related to the X chromosome location of the PDH E1 gene. These include the broad spectrum of clinical presentations and problems of diagnosis, especially antenatal diagnosis, in females.     

前列腺素E1临床应用近况

前列腺互Ｅ１具有广泛的药理作用，已被用于治疗多种临床病种，并取得显著疗效，本文特综合了部分国内外近期文献，就前列腺素Ｅ１的临床应用近况作一阐述。     

Characterization of the mutations in three patients with pyruvate dehydrogenase E1α deficiency

Summary The human pyruvate dehydrogenase complex catalyses the oxidative decarboxylation of pyruvate to acetyl-CoA. Defects in several of the seven subunits have been reported, but the majority of mutations affect the E1 component and especially the E1 subunit. However, the clinical presentation of patients with pyruvate dehydrogenase E1 deficiency is extremely variable. Dependency of the brain on pyruvate dehydrogenase activity and localization of the gene for the somatic form of the pyruvate dehydrogenase E1 subunit to the X chromosome provide the basis for a better understanding of the variation in the clinical manifestations. Further understanding of the function and interaction of subunits and the pathophysiology of pyruvate dehydrogenase deficiency necessitates the characterization of mutations in the pyruvate dehydrogenase complex. We report the analysis of three patients with pyruvate dehydrogenase E1 deficiency. One female has a three base pair deletion which affects dephosphorylation of the subunit. Of two males analysed, one has a two base pair deletion causing a shift in the reading frame. The other has a base change, resulting in an Arg to His substitution. All three mutations are located near the carboxyl terminus of the subunit.     

Detection of hepatitis E virus RNA in sera of patients with hepatitis E by polymerase chain reaction

Introduction H epatitis E, the major form of enterically transmitted non-A, non-B hepatitis, is caused by hepatitis E virus (HEV).[1] The disease is a serious public health problem in many developing countries in Asia, the Middle East, and Africa, as well as in Mexico, where sanitation conditions are suboptimal.[2] HEV is transmitted primarily by the fecal-oral route through contaminated water.[3] The overall mortality rate of hepatitis E is generally lower than 1%, but it can be as high…     

SIRT1和E2F1的研究进展

随着人类对肿瘤的了解和认识不断加深,人类对肿瘤的基因方面的研究应运而生。SIRT是一种具有烟碱腺嘌呤二核苷酸依赖性的蛋白脱乙酰化酶,参与细胞增殖、衰老、凋亡、分化等生理活动。迄今为止,人类细胞内发现了7种不同类型的SIRT蛋白,分别命名为SIRT1～7。其中SIRT1是目前关于肿瘤相关性研究较多的一个,在抑制凋亡、延缓衰老、延长寿命中发挥着重要作用。E2F家族是一组能够编码转录调节因子的基因,是细胞周期进程的重要调控因子。其中E2F1是细胞周期的重要正向调控因子,在细胞从G0/G1期进入S期的进程中发挥着关键作用,即促进进入S期的细胞明显增多。众多研究表明,转录因子SIRT1和E2F1在细胞周期,细胞凋亡和肿瘤发生、发展过程中都具有重要的作用。相信随着对这两个基因研究的日益深入,其与细胞凋亡、细胞周期以及肿瘤的关系将逐渐明确,必定会为肿瘤的诊断和治疗提供更多有价值的思路。     

Effect of vitamin E succinate on expression of TGF-β_1, c-Jun and JNK1 in human gastric cancer SGC-7901 cells

Vitamin E succinate(RRR-α-Tocopheryl Succinate,VES), a derivative of natural vitamin E, is acompound esterified by succinic acid and 6-hydroxyl-α-tocopheryl. VES can increase thestability of α-tocopheryl and protect 6-hydroxylfrom oxidation. Nowadays, this kind of vitamin Ehas been on sale on the markets. Previous researchesindicate that VES has an evident inhibitory effecton the growth of various tumor cells, but has noharm to the growth of normal cells. Theexperiment in vivo has demonstrated that VES can     

E1 of α-ketoglutarate dehydrogenase defends Mycobacterium tuberculosis against glutamate anaplerosis and nitroxidative stress

Enzymes of central carbon metabolism (CCM) in Mycobacterium tuberculosis (Mtb) make an important contribution to the pathogen’s virulence. Evidence is emerging that some of these enzymes are not simply playing the metabolic roles for which they are annotated, but can protect the pathogen via additional functions. Here, we found that deficiency of 2-hydroxy-3-oxoadipate synthase (HOAS), the E1 component of the α-ketoglutarate (α-KG) dehydrogenase complex (KDHC), did not lead to general metabolic perturbation or growth impairment of Mtb, but only to the specific inability to cope with glutamate anaplerosis and nitroxidative stress. In the former role, HOAS acts to prevent accumulation of aldehydes, including growth-inhibitory succinate semialdehyde (SSA). In the latter role, HOAS can participate in an alternative four-component peroxidase system, HOAS/dihydrolipoyl acetyl transferase (DlaT)/alkylhydroperoxide reductase colorless subunit gene (ahpC)-neighboring subunit (AhpD)/AhpC, using α-KG as a previously undescribed source of electrons for reductase action. Thus, instead of a canonical role in CCM, the E1 component of Mtb’s KDHC serves key roles in situational defense that contribute to its requirement for virulence in the host. We also show that pyruvate decarboxylase (AceE), the E1 component of pyruvate dehydrogenase (PDHC), can participate in AceE/DlaT/AhpD/AhpC, using pyruvate as a source of electrons for reductase action. Identification of these systems leads us to suggest that Mtb can recruit components of its CCM for reactive nitrogen defense using central carbon metabolites.The bacterium Mycobacterium tuberculosis (Mtb), which causes tuberculosis, has plagued humanity since antiquity (1), is estimated to infect one-third of the population today, and is the leading cause of death by a bacterium. This success as a pathogen reflects Mtb’s metabolic plasticity and resistance to host immunity (2, 3). Recent evidence suggests that certain enzymes of central carbon metabolism (CCM) can mediate both of these facets of Mtb’s adaptation to the host (4–8). Here, we demonstrate that Rv1248c, recently named 2-hydroxy-3-oxoadipate synthase (HOAS) (9), is one such enzyme.Rv1248c was first annotated as the thiamin diphosphate (ThDP)-dependent E1 component (SucA) of a canonical α-ketoglutarate (α-KG) dehydrogenase complex (KDHC) that produces succinyl CoA (SucCoA) via oxidative decarboxylation of α-KG with concomitant transfer of the resulting succinyl group to CoA (10). Classically, KDHC, composed of three enzymes, joins the oxidative and reductive half-cycles of the TCA cycle (SI Appendix, Fig. S1). The TCA cycle generates high-energy phosphate bonds and biosynthetic precursors of amino acids, nucleotides, and fatty acids (11). However, KDHC activity was not detected in Mtb lysates, and the gene product annotated as the lipoamide-bearing E2 component [Rv2215, dihydrolipoyl succinyl transferase (SucB)] functions as the E2 component dihydrolipoyl acetyl transferase (DlaT) of the pyruvate dehydrogenase complex (PDHC) (5, 12, 13). The Mtb genome does not encode another SucB (12), and KDHC activity could not be demonstrated with purified recombinant Rv1248c plus DlaT and E3 [lipoamide dehydrogenase (Lpd)] in a manner similar to cognate proteins from other actinomycetes (14). Rv1248c by itself produces succinate semialdehyde (SSA) from nonoxidative decarboxylation of α-KG in vitro, and Mtb’s succinate semialdehyde dehydrogenases (SSADHs) can generate succinate from SSA, completing a modified TCA cycle (13). Subsequently, activity-based metabolomic profiling revealed yet another function of Rv1248c that predominated over SSA production: decarboxylation of α-KG, followed by carboligation with glyoxylate to form 2-hydroxy-3-oxoadipate (HOA). Thus, Rv1248c was renamed HOAS (9). Decarboxylation of α-KG is the first step in all three reactions. The Mycobacterium smegmatis α-ketoglutarate decarboxylase (MsKGD) homolog was found to catalyze all three reactions in vitro, with augmentation of catalysis by acetyl CoA (AcCoA)-mediated allosteric modulation (15), whereas Mtb HOAS showed a kinetic preference for the HOAS pathway in vitro (16).HOAS activity is regulated in Mtb by glycogen accumulation regulator A (GarA), whose activity is controlled, in turn, by Ser/Thr kinases PknG and PknB (SI Appendix, Fig. S1B). GarA also regulates glutamate dehydrogenase (GDH) and glutamate synthase/glutamine oxoglutarate aminotransferase (17). Coregulation of these three enzymes by GarA calls attention to the contribution of HOAS to Mtb’s metabolism of glutamate. Glutamate serves as an anaplerotic substrate entering the TCA cycle as α-KG and is also a key intermediate in nitrogen assimilation and metabolism (18, 19).Despite extensive studies, the physiological function of HOAS in Mtb and its contribution to virulence remain unknown. Here, we brought genetics, metabolomics, enzymology, and mouse models of infection to bear on that question, using the hoas deletion mutant in Mtb and the deletion mutant complemented in three ways: with the WT allele, with an allele with a point mutation that abrogates catalysis, or with an allele with a point mutation that is insensitive to allosteric regulation by AcCoA. In standard culture conditions, Δhoas showed no defect in growth or changes in levels of CCM metabolites, arguing against Mtb’s reliance on the conventional function of KDHC. However, situational stresses revealed striking phenotypes in Δhoas, indicative of a defensive role of HOAS against products arising from metabolism of glutamate and against reactive nitrogen intermediates (RNIs). Mechanistic analysis of the latter phenotype revealed a previously undescribed route to antioxidant defense mediated by substrates and enzymes of CCM.     

Biochemical characterization of two mutants of human pyruvate dehydrogenase, F205L and T231A of the E1α subunit

Mutations in the E1alpha subunit of the pyruvate dehydrogenase multienzyme complex may result in congenital lactic acidosis, but little is known about the consequences of these mutations at the enzymatic level. Here we characterize two mutants (F205L and T231A) of human pyruvate dehydrogenase in vitro, using the enzyme expressed in Escherichia coli. Wild-type and mutant proteins were purified successfully and their kinetic parameters were measured. F205L shows impaired binding of the thiamin diphosphate cofactor, which may explain why patients carrying this mutation respond to high-dose vitamin B1 therapy. T231A has very low activity and a greatly elevated Km for pyruvate, and this combination of effects would be expected to result in severe lactic acidosis. The results lead to a better understanding of the consequences of these mutations on the functional and structural properties of the enzyme, which may lead to improved therapies for patients carrying these mutations.     

前列腺E1的肝保护作用

动物实验表明ＰＧＥ１对实验动物肝损害有保护作用。临床研究表明，ＰＧＥ１对急性爆发性及亚急性爆发性肝炎等重症肝炎，可使ＡＬＴ降低、胆红素降低、ＰＴ缩短从而改善肝功能。ＰＧＥ１通过增加肝血流，加速线粒体呼吸功能的恢复，稳定细胞膜微粘度的稳定性，降低细胞介导的肝细胞毒性，刺激肝组织ｃＡＭＰ的产生，增加ＡＴＰ的水平，促进ＤＮＡ的合成而实现其肝保护作用。ＰＧＥ可引起多系统的不良反应，这些反应可在减量或停药后     

前列腺素E1治疗糖尿病足疗效观察

目的观察前列腺素E1治疗糖尿病足的疗效.方法48例糖尿病足患者随机分成治疗组26例和对照组22例,治疗组给予前列腺素E1治疗.结果治疗组治愈率、总有效率均明显高于对照组(P＜0.05),平均好转天数、平均治愈天数均明显短于对照组(P＜0.05).结论前列腺素E1是治疗糖尿病足安全有效的药物.