Enzymatically synthesized glycogen reduces lipid accumulation in diet-induced obese rats

Based on a recent study indicating that enzymatically synthesized glycogen (ESG) possesses a dietary, fiber-like action, we hypothesized that ESG can reduce the risk of obesity. In this study, the antiobesity effects of ESG were investigated in a model of diet-induced obesity. Male Sprague-Dawley rats were divided into 4 groups and fed a normal or high-fat diet, with or without 20% ESG, for 4 weeks. Body weight, food intake, lipid deposition in the white adipose tissues and liver, fecal lipid excretion, and plasma lipid profiles were measured. At week 3, the body fat mass was measured using an x-ray computed tomography system, which showed that ESG significantly suppressed the high-fat diet–induced lipid accumulation. Similar results were observed in the weight of the adipose tissue after the experiment. Moreover, ESG significantly suppressed the lipid accumulation in the liver but increased fecal lipid excretion. The plasma concentrations of triacylglycerol and nonesterified fatty acid were lowered after a high-fat diet, whereas the total bile acid concentration was increased by ESG. However, the hepatic messenger RNA (mRNA) levels of enzymes related to lipid metabolism were not affected by ESG. Conversely, the mRNA levels of long-chain acyl-CoA dehydrogenase and medium-chain acyl-CoA dehydrogenase were up-regulated by ESG in the muscle. These results suggest that the combined effects of increased fecal lipid excretion, increased mRNA levels of enzymes that oxidize fatty acids in the muscle, and increased total bile acid concentration in the plasma mediate the inhibitory effect of ESG on lipid accumulation.     

Relationship of afferentation with soma size of nucleus gracilis neurons after bilateral dorsal column lesion in the rat

The effect of bilateral dorsal column lesion on the afferentation and diameter of neurons in the nucleus gracilis (NG) of the rat was studied during 120 postoperative days. After bilateral, low thoracic lesion of the dorsal column, the animals were killed 1, 2, 3, 7, 14, 30, 45, 60, 90, or 120 days later, and cells in the rostral, middle, or caudal NG were selected and measured for soma diameter and number of boutons on these same somas. The results showed significant reduction in soma diameter during the first 2 weeks postoperatively compared with normals, and also significant changes (increases or decreases in diameter) in survival times during 120 postoperative days. Soma diameter and number of boutons on the soma were positively correlated at all NG levels and survival times. Extrapolations of those values to total surface area and total surface area of soma covered by boutons, show that (i) neither normal nor deafferented soma are totally innervated, and (ii) normal innervation values are maintained in parallel with fluctuations in the total surface area of the soma. These results emphasize the dynamic changes occurring upon and in the postsynaptic cell after deafferentation, and imply a mechanism which regulates the interaction of quantity of presynaptic afferent fibers upon, and size of, the postsynaptic cell body.     

Effects of a membrane sugar analogue, 6-deoxy-6-fluoro-d-galactose,on the L1210 leukemic cell ectosialyltransferase system

In L1210 leukemia cells, 6-deoxy-6-fluoro-d-galactose specifically inhibited the incorporation of [³H]-d-galactose, while that of other precursors of glycoconjugate biosynthesis, including mannose and glucosamine, was unaffected. The activation of [6-³H]-6-deoxy-6-fluoro-d-galactose to a nucleotide sugar was similar to that found for [³H]-d-galactose. The incorporation of either sugar after 1 hr was visualized by electron microscopic autoradiography to be in the Golgi region. Treatment of L1210 cells with 6-deoxy-6-fluoro-d-galactose in vitro or in vivo resulted in a specific, dose- and time-dependent decrease in the activity of cell surface sialyltransferase (ectosialyltransferase) but not of 5′-nucleotidase, a plasma membrane marker enzyme. The decrease in ectosialyltransferase activity appeared to be selective and is suggested to be due to structural modification of the cell surface galactoprotein acceptors for this enzyme. The data indicate that 6-deoxy-6-fluoro-d-galactose is an effective modifier of cellular glycoconjugate in that its incorporation into certain cell surface components results in a modification of plasma membrane structure and function.     

Effect of nitroheterocyclic drugs on lipid peroxidation and glutathione content in rat liver extracts

Incubation of rat liver cell-free extracts with an NADPH-generating system and with nifurtimox or benznidazole (two nitroheterocyclic drugs used in the treatment of Chagas' disease) produced oxidation of reduced glutathione (GSH) and increased lipid peroxidation, as shown by the generation of thiobarbituric-acid-reacting intermediates. Nifurtimox and benznidazole inhibited GSSG-reductase, but not GSH-peroxidase, the former inhibition contributing to GSH depletion. In every case, nifurtimox was more effective than benznidazole. Addition of GSH or free-radical scavengers (catalase, superoxide dismutase, mannitol, sodium benzoate or L-histidine) prevented the effect of nifurtimox on lipid peroxidation reactions. These results support the assumption [M. Dubin, S. N. J. Moreno, E. E. Martino, R. Docampo and A. O. M. Dubin, Biochem. Pharmac.32, 483 (1983)] that, in the rat liver, GSH exerts a protective action against oxygen radicals generated by the nitroheterocyclic drugs.     

Effect of simvastatin on the oxidation of native and modified lipoproteins

Modified (oxidized) low-density lipoprotein (LDL) plays a significant role in atherosclerosis by accumulation in arteries. Also, glycated LDL, such as in diabetics, are increasing the risk for atherosclerosis, due to an increased oxidizability as compared to native LDL. For these reasons, the potential inhibition of such modifications is of clinical importance. We investigated the influence of simvastatin on oxidation of native and modified LDL as well as high-density lipoprotein (HDL), which plays a protective role in atherosclerosis. Quantitative assessment of the oxidation end-product malondialdehyde (MDA) revealed the highest inhibitory rate for HDL at concentrations of 1.6 microg/ml and 0.8 microg/ml by 30.3% and 20.4%, at 6 h and 4 h, respectively. At 24 h, the inhibition was still persisting amounting to 27.9% and 20.3%, respectively. For native LDL, we found less inhibition of oxidation at a concentration of 1.6 microg/ml amounting to 19.2% and 11.5%, for 4 h and 6 h, respectively. Similar effects were found at a concentration of 0.8 microg/ml. For modified, glycated LDL, the most pronounced effect was found at a concentration of 1.6 microg/ml amounting to 22.4% for the period of 2-24 h of oxidation. For glycoxidated LDL, the inhibition of oxidation was less expressed amounting to 10.1% for the period of 2-6 h at the same concentration. The influence of simvastatin on lag time (protection from oxidation) by diene conjugation was also investigated. At the highest concentration of simvastatin (1.6 microg/ml), we found a prolongation of lag time from 73 min to 99 min for native LDL, for glycoxidated LDL 60 min to 89 min and for HDL 54 min to 64 min. For glycated LDL, only a small decrease of lag time (66 min versus 71 min) at same concentration was observed. For glycated and glycoxidated LDL, we found a moderate increase in relative electrophoretic mobility (REM) by 2.0 and 2.3, respectively, but no changes in the presence of simvastatin were observed. These data show that simvastatin besides its lipid-lowering action has also significant antioxidative properties.     

血清酶活性联检在肝病中的应用

目的:联合检测总胆汁酸(TBA)、丙氨酸氨基转移酶(ALT)、γ-谷氨酰转移酶(γ-GT)、碱性磷酸酶(ALP)血清水平,以探讨四项指标对肝病的诊断价值。方法:采用循环酶法检测TBA;连续监测法检测ALT、γ-GT、ALP。测定肝病患者160例,其中急性肝炎(AH)81例;慢性活动性肝炎(CAH)48例;肝硬化(LC)26例;肝癌(HCC)5例。健康体检人群共80例。结果:对照组TBA、ALT、γ-GT、ALP检测(x-±s)结果与肝病各组比较差异均有显著性P<0.01和有差异P<0.05。TBA、γ-GT检测的阳性率在AH、CAH、LC、HCC各组都达到80%以上。结论:正常细胞向恶性细胞转化常导致酶合成异常,酶学改变出现在形态学改变之前,联合检测四项指标可以提高肝病的诊断率和鉴别诊断,在疗效监测方面可为临床提供有价值的资料。     

胎盘FIC1 mRNA的表达及其与ICP关系的研究

目的通过研究妊娠期肝内胆汁淤积症(ICP)胎盘胆盐载体家族性肝内胆汁淤积相关蛋白-1(FIC1)mRNA的表达,以及母胎血中总胆汁酸(TBA)和甘胆酸(CG)水平的变化,探讨胎盘胆盐载体在ICP胎儿病理机制中的作用。方法纳入ICP患者(ICP组)及正常孕妇(对照组)各20例。采用速率法测定母体静脉、脐静脉血中TBA水平;测定放射免疫法CG水平;RT-PCR法测定胎盘组织中胆盐载体FIC1 mRNA表达;另采用原位杂交法对随机选取的两组各两例胎盘组织进行FIC1 mRNA的定位检测。结果1ICP组母血和脐血中的TBA、CG水平均高于对照组,差异有统计学意义(P<0.05)。ICP组母血中TBA、CG水平均高于脐血(25.77±16.64)μmol/Lvs(8.55±5.48)μmol/L;(3416.09±1986.04)μg/dLvs(821.84±673.17)μg/dL,差异有统计学意义(P<0.05);对照组母血和脐血中TBA水平(3.40±2.51)μmol/Lvs(4.37±3.26)μmol/L、CG水平(342.74±234.88)μg/dLvs(309.32±145.20)μg/dL比较,差异无统计学意义(P>0.05)。2ICP组、对照组胎盘组织中均有FIC1 mRNA的表达,且均定位于合体滋养细胞。ICP组FIC1 mRNA表达量低于对照组(0.76±1.22vs37.28±75.03),差异有统计学意义(P<0.05)。3ICP组和对照组胎盘组织中FIC1 mRNA表达量与母血、脐血中TBA和CG水平均无相关性(r=-0.229~0.163,P>0.05)。结论胎盘FIC1 mRNA表达降低,这可能是导致胎盘对胆汁酸的转运障碍,引起ICP胎儿体内胆淤的因素之一。     

肝硬化血清总胆汁酸检测的临床意义

①目的 探讨肝硬化患者血清总胆汁酸（TBA）与肝纤维化标志物及其与Child-pugh分级的关系。②方法检测56例肝硬化患者的血清TIH、胆红素、凝血酶原时间、透明质酸（HA）、Ⅲ型前肢原（PCⅢ）、Ⅳ胶原（Ⅳ-C）及层黏蛋白（LN）。③结果随着Child-pugh分级的增加．血清HA、PCⅢ、Ⅳ-C、LN及TBA水平逐步增高，C级与A级比较均有显著性差异（P〈0．01）。血清TBA与PCⅢ、Ⅳ-C及HA呈显著正相关（P〈0．005；P〈0．05；P〈0、0005），但与LN相关不显著（P〉0．05）。④结论血清TBA升高与肝纤维化及Chihl-pugh分级有密切关系，联合检测TBA与肝纤维化标志物，对判断肝硬化患者病情及预后有重要参考意义。     

Chemistry,antioxidant and antimicrobial investigations on essential oil and oleoresins of Zingiber officinale

The essential oil and oleoresins (ethanol, methanol, CCl₄ and isooctane) of Zingiber officinale were extracted respectively by hydrodistillation and Soxhlet methods and subjected to GC–MS analysis. Geranial (25.9%) was the major component in essential oil; eugenol (49.8%) in ethanol oleoresin, while in the other three oleoresins, zingerone was the major component (33.6%, 33.3% and 30.5% for, methanol, CCl₄ and isooctane oleoresins, respectively). The antioxidant activity of essential oil and oleoresins were evaluated against mustard oil by peroxide, anisidine, thiobarbituric acid (TBA), ferric thiocyanate (FTC) and 2,2′-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging methods. They were found to be better antioxidants than butylated hydroxyanisole (BHA). The antimicrobial properties were also studied using various food-borne pathogenic fungal and bacterial species. The essential oil and CCl₄ oleoresin showed 100% zone inhibition against Fusarium moniliforme. For other tested fungi and bacteriae, the essential oil and all oleoresins showed good to moderate inhibitory effects. Though, both essential oil and oleoresins were found to be effective, essential oil was found to be better than the oleoresins.