Effects of Bleomycin on Liver Antioxidant Enzymes and the Electron Transport System From Ad Libitum-Fed and Dietary-Restricted Female and Male Fischer 344 Rats
摘要:
Dietary restriction (DR) is the only known intervention that delays aging and age-related diseases. Mechanisms proposed to explain this DR effect include a decline in free radical production and an increase in free radical detoxification. In the present study the effect of bleomycin (BLM) as a reactive oxygen species-generating antitumor drug has been evaluated on antioxidant enzymes and the electron transport system in different cellular fractions of liver in female and male Fischer 344 rats. Animals were fed ad libitum (AL) or 60% of the AL intake (DR) and were given a single intraperitoneal injection of 2.5, 5, or 10 mg BLM/kg body wt. After four weeks, BLM significantly increased glutathione peroxidase and lactate dehydrogenase activities in liver cytosol of female AL rats and increased activity even more in male rats. Similar changes were also noted for glutathione reductase and glucose 6-phosphate dehydrogenase activities in BLM-treated AL rats. In liver mitochondria, glutathione peroxidase was increased in female and male AL rats but was increased more in female rats. Drug treatment had no significant effect on these enzyme activities in cytosolic or mitochondrial fractions of DR animals. Profound effects of BLM were noted in activities of complexes I, III, and IV of the electron transport system in AL and DR female and male rats; however, complex II demonstrated no significant diet or treatment effect. Induced antioxidant enzyme activities in BLM-treated AL rats may be a response to excessive free radical generation due to BLM metabolism in AL animals that is mitigated by DR. Furthermore, dysfunction of the electron transport system might suggest its role in a secondary generation of free radicals during BLM metabolism contributing to its toxicity.
Biomimetic Total Synthesis of Bisorbicillinol, Bisorbibutenolide, Trichodimerol, and Designed Analogues of the Bisorbicillinoids
作者:K. C. Nicolaou、Georgios Vassilikogiannakis、Klaus B. Simonsen、Phil S. Baran、Yong-Li Zhong、Veroniki P. Vidali、Emmanuel N. Pitsinos、Elias A. Couladouros
DOI:10.1021/ja9942843
日期:2000.4.1
biological activity and are associated with fascinating hypotheses for their biosynthesis. A full account of our biomimetic explorations toward the bisorbicillinoids including the totalsyntheses of bisorbicillinol (1), bisorbibutenolide (2), and trichodimerol (4) from sorbicillin (3) is disclosed. Utilizing the novel dimerization reactions discovered and fine-tuned en route to 1 and 4, several analogues of
Total Synthesis and Stereochemical Assignment of (±)-Sorbiterrin A
作者:Chao Qi、Tian Qin、Daisuke Suzuki、John A. Porco
DOI:10.1021/ja500854q
日期:2014.3.5
sorbiterrin A has been developed employing consecutive Michael additions of a 4-hydroxypyrone to a sorbicillinol derivative and silver nanoparticle-mediated bridged aldol/dehydration to construct the [3.3.1] ring system. The relativestereochemistry of sorbiterrin A was unambiguously confirmed by X-ray crystallographic analysis.
已经开发了一种针对山梨糖醇酐 A 的简明仿生方法,该方法采用连续迈克尔加成将 4-羟基吡喃酮添加到山梨醇衍生物和银纳米颗粒介导的桥接羟醛/脱水来构建 [3.3.1] 环系统。X 射线晶体学分析明确证实了山梨糖醇 A 的相对立体化学。
Biocatalytic site- and enantioselective oxidative dearomatization of phenols
作者:Summer A. Baker Dockrey、April L. Lukowski、Marc R. Becker、Alison R. H. Narayan
DOI:10.1038/nchem.2879
日期:2018.2
Biocatalytic site- and enantioselective oxidative dearomatization of phenols Biocatalytic site- and enantioselective oxidative dearomatization of phenols, Published online: 13 November 2017; doi:10.1038/nchem.2879NatureArticleSnippet(type=short-summary, markup= Within natural product biosynthetic pathways, nature has evolved highly selective catalysts capable of complexity generating reactions. Leveraging
Synthesis of three natural 1,3-diarylpropanes: Two revised structures
作者:Anselmo A. Morais、Raimundo Braz Fo、Silas V. Fraiz
DOI:10.1016/0031-9422(89)85046-0
日期:——
5′-dimethylphenyl)-3-(2″-hydroxy-4″,5″-methylenedioxyphenyl)-Propane, isolated from Iryanthera coriacea and I. laevis, 1-(2′-hydroxy-4′-methoxy-5′-methylphenyl)-3-(2″-hydroxy-4″,5″-methylene-dioxyphenyl)-propane, isolated from I. laevis, and 1-(2′-hydroxy-4′-methoxyphenyl)-3-(3″-hydroxy-4″-methoxyphenyl)-propane, isolated fromVirolamultinervia, were synthesized by processes which involved catalytic hydrogenation
摘要 1-(2',4'-dihydroxy-3',5'-二甲基苯基)-3-(2"-hydroxy-4",5"-methylenedioxyphenyl)-Propane,从 Iryanthera coriacea 和 I. laevis 中分离出来,1 -(2'-羟基-4'-甲氧基-5'-甲基苯基)-3-(2"-羟基-4",5"-亚甲基-二氧苯基)-丙烷,从 I. laevis 中分离,和 1-(2 '-羟基-4'-甲氧基苯基)-3-(3″-羟基-4″-甲氧基苯基)-丙烷,从多神经病毒中分离,通过涉及适当查耳酮的催化氢化和二氢查耳酮的克莱门森还原的方法合成。仅修订了从 V. multinervia 和 I. laevis 中分离出来的 1,3-二芳基丙烷的结构。