fructose

果糖
  • 文章类型: Journal Article
    背景:甘蔗糖蜜,富含蔗糖,葡萄糖,和果糖,由于其丰富和低成本,为工业发酵提供了有前途的碳源。然而,挑战来自同时利用多种糖和碳分解代谢物抑制(CCR)。尽管它的营养成分,大肠杆菌中的蔗糖代谢,除了W菌株,仍然知之甚少,阻碍其在微生物发酵中的使用。在这项研究中,大肠杆菌W被设计为提高糖消耗率并克服CCR。这是通过整合合成设计的csc操纵子和优化葡萄糖和果糖共利用途径来实现的。这些进步有助于有效利用甘蔗糖蜜生产3-羟基丙酸(3-HP),促进可持续的生化生产过程。
    结果:在这项研究中,我们解决了与大肠杆菌W中糖代谢相关的挑战,重点提高蔗糖消耗和提高葡萄糖-果糖的共利用。通过对蔗糖利用系统的针对性工程,我们通过调节csc操纵子组件的表达来实现加速的蔗糖消耗率,CSCB,CSCK,cscA,和CSCR。我们的发现揭示了csc基因的单顺反子表达与cscR的缺失,导致最佳的蔗糖利用率,而没有显著的生长负担。此外,我们通过调节FruR与果糖PTS调节子的结合动力学,成功地减轻了果糖分解代谢物的抑制,实现葡萄糖和果糖的几乎等效的共同利用。为了验证我们工程菌株的工业适用性,我们追求3-HP生产甘蔗糖蜜。通过整合异源基因和优化代谢途径,与以前的研究相比,我们在3-HP滴度方面取得了改善.此外,甘油醛-3-磷酸脱氢酶(gapA)抑制有助于碳通量的重新分布,增强糖蜜转化为3-HP。
    结论:尽管蔗糖代谢受到限制,重新设计的大肠杆菌W菌株,擅长利用甘蔗糖蜜,是工业发酵的宝贵资产。其合成的csc操纵子增加蔗糖消耗,同时减轻CCR提高葡萄糖-果糖的共同利用。这些增强,再加上对gapA的压制,旨在有效地将甘蔗糖蜜转化为3-HP,解决工业应用中蔗糖和果糖代谢的局限性。
    BACKGROUND: Sugarcane molasses, rich in sucrose, glucose, and fructose, offers a promising carbon source for industrial fermentation due to its abundance and low cost. However, challenges arise from the simultaneous utilization of multiple sugars and carbon catabolite repression (CCR). Despite its nutritional content, sucrose metabolism in Escherichia coli, except for W strain, remains poorly understood, hindering its use in microbial fermentation. In this study, E. coli W was engineered to enhance sugar consumption rates and overcome CCR. This was achieved through the integration of a synthetically designed csc operon and the optimization of glucose and fructose co-utilization pathways. These advancements facilitate efficient utilization of sugarcane molasses for the production of 3-hydroxypropionic acid (3-HP), contributing to sustainable biochemical production processes.
    RESULTS: In this study, we addressed challenges associated with sugar metabolism in E. coli W, focusing on enhancing sucrose consumption and improving glucose-fructose co-utilization. Through targeted engineering of the sucrose utilization system, we achieved accelerated sucrose consumption rates by modulating the expression of the csc operon components, cscB, cscK, cscA, and cscR. Our findings revealed that monocistronic expression of the csc genes with the deletion of cscR, led to optimal sucrose utilization without significant growth burden. Furthermore, we successfully alleviated fructose catabolite repression by modulating the binding dynamics of FruR with the fructose PTS regulon, enabling near-equivalent co-utilization of glucose and fructose. To validate the industrial applicability of our engineered strain, we pursued 3-HP production from sugarcane molasses. By integrating heterologous genes and optimizing metabolic pathways, we achieved improvements in 3-HP titers compared to previous studies. Additionally, glyceraldehyde-3-phosphate dehydrogenase (gapA) repression aids in carbon flux redistribution, enhancing molasses conversion to 3-HP.
    CONCLUSIONS: Despite limitations in sucrose metabolism, the redesigned E. coli W strain, adept at utilizing sugarcane molasses, is a valuable asset for industrial fermentation. Its synthetic csc operon enhances sucrose consumption, while mitigating CCR improves glucose-fructose co-utilization. These enhancements, coupled with repression of gapA, aim to efficiently convert sugarcane molasses into 3-HP, addressing limitations in sucrose and fructose metabolism for industrial applications.
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  • 文章类型: Journal Article
    小檗碱(BBR)是中药黄连、黄柏的主要活性成分,经常被用来治疗肝脏疾病。氧化应激和炎症是两个关键的肝脏病理标志。本研究旨在探讨BBR对果糖诱导的大鼠肝损伤模型的潜在作用及机制,HepG2和BRL-3A细胞的肝细胞损伤。我们的结果表明,BBR有效逆转果糖诱导的体重增加,葡萄糖不耐受,和胰岛素抵抗,可观察到的异常组织病理学改变减弱,ALT和AST的血清活性改善。体内和体外,BBR显著减轻促炎细胞因子IL-6和TNF-α的分泌,和抗炎细胞因子IL-10水平升高。BBR还通过显着降低ROS和MDA的细胞内含量来减弱氧化应激,提高SOD酶活性和GSH水平。此外,BBR显著上调Nrf2、HO-1和p-AMPK的蛋白表达,和p-AMPK的荧光水平。此外,BBR显著提高AMP水平,AMP/ATP的比值,促进了ADK的表达。然而,siADK消除了BBR对HepG2和BRL-3A细胞的益处。最后,BBR的肝保护作用被认为与抗炎和抗氧化作用密切相关,至少部分地,通过ADK/AMPK/Nrf2信号。这项工作为黄连和黄柏在肝脏保护中的传统应用提供了进一步的支持,并可能为BBR的临床应用提供新的维度。为药物设计提供了一种有前途的先导化合物。
    Berberine (BBR) is a major active component of traditional Chinese medicine Rhizoma Coptidis and Cortex Phellodendri, which have been frequently used to treat liver diseases. Oxidative stress and inflammation are two pivotal hepatic pathological hallmarks. This study aimed to explore the potential effect and underlying mechanism of BBR on fructose-induced rat liver injury model, and hepatocyte damage in HepG2 and BRL-3A cells. Our results indicated that BBR effectively reversed fructose-induced body weight gain, glucose intolerance, and insulin resistance, observably attenuated abnormal histopathological alterations and ameliorated serum activities of ALT and AST. In vivo and in vitro, BBR significantly alleviated the secretion of pro-inflammatory cytokines IL-6 and TNF-α, and elevated levels of anti-inflammatory cytokine IL-10. BBR also attenuated oxidative stress by markedly decreasing intracellular contents of ROS and MDA, and increasing SOD enzymatic activity and GSH level. Furthermore, BBR substantially upregulated the protein expression of Nrf2, HO-1 and p-AMPK, and the fluorescence level of p-AMPK. In addition, BBR significantly increased the level of AMP, the ratio of AMP/ATP, and promoted the expression of ADK. Nevertheless, siADK abolished the benefits exerted by BBR on HepG2 and BRL-3A cells. Conclusively, the hepatoprotective effect of BBR was believed to be intimately associated with anti-inflammatory and antioxidant action mediated, at least partially, via ADK/AMPK/Nrf2 signaling. This work provided further support for the traditional application of Rhizoma Coptidis and Cortex Phellodendri in liver protection and might shed novel dimension to the clinical application of BBR, providing a promising lead compound for drug design.
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  • 文章类型: Journal Article
    西方饮食中典型的高果糖和高盐饮食的组合会导致高血压,主动脉硬化,啮齿动物的左心室(LV)舒张功能障碍和肾功能受损。尽管饲喂高果糖和高盐的大鼠肾素-血管紧张素系统(RAS)被激活,RAS通路的急性抑制不会改善心脏和血管参数。很可能需要长期治疗以允许重塑和改善心血管功能。因此,我们假设慢性RAS抑制果糖+高盐喂养大鼠将血压(BP)恢复到与葡萄糖+正常盐喂养对照相似的水平,将改善心肾功能和组织病理学.
    通过血液动力学遥测监测的雄性和雌性SpragueDawley大鼠在基线期间喂食0.4%NaCl食物,然后改为含有20%葡萄糖+0.4%NaCl(G)或20%果糖+4%NaCl(F)的食物,并用赋形剂处理,依那普利(Enal,4mg/kg/d)或氯沙坦(Los,8mg/kg/d),通过渗透微型泵进行25-26天。
    在两种性别的果糖高盐组中,BP升高(P<0.05),并通过Enal或Los恢复到对照水平。雌性FLos大鼠的脉搏波速度(PWV)较低,雌性FEnal大鼠的心输出量较高。GFR没有因饮食或治疗而改变。两种性别的果糖高盐组均显示出更高的白蛋白尿,而Enal可降低雄性大鼠的白蛋白尿。在两种性别的果糖高盐喂养大鼠中,心脏纤维化和系膜细胞过多都更大,并且Los或Enal改善了。
    因此,抑制RAS可以改善高果糖和高盐饮食的雄性大鼠的性别和蛋白尿的早期心脏和肾脏组织病理学变化。心肾参数的功能改善可能需要更长时间的治疗。
    UNASSIGNED: The combination of a high fructose and high salt diet typical of western diet induces high blood pressure, aortic stiffening, left ventricular (LV) diastolic dysfunction and impaired renal function in rodents. Despite an activated renin-angiotensin system (RAS) in rats fed high fructose and high salt, acute inhibition of the RAS pathway does not improve cardiac and vascular parameters. It may well be that longer term treatment is required to permit remodeling and improve cardiovascular function. Thus, we hypothesized that chronic RAS inhibition fructose+high salt-fed rats to restore blood pressure (BP) to levels similar to glucose plus normal salt-fed controls will improve cardiorenal function and histopathology.
    UNASSIGNED: Male and female Sprague Dawley rats monitored by hemodynamic telemetry were fed 0.4% NaCl chow during baseline, then changed to chow containing either 20% glucose+0.4% NaCl (G) or 20% fructose+4% NaCl (F) and treated with vehicle, enalapril (Enal, 4 mg/kg/d) or losartan (Los, 8 mg/kg/d) by osmotic minipump for 25-26 days.
    UNASSIGNED: BP was elevated in the fructose+high salt groups of both sexes (P < 0.05) and restored to control levels by Enal or Los. Pulse wave velocity (PWV) was lower in female F+Los rats and cardiac output higher in female F+Enal rats. GFR was not changed by diet or treatment. Fructose+high salt groups of both sexes displayed higher albuminuria that was decreased by Enal in male rats. Cardiac fibrosis and mesangial hypercellularity were greater in fructose+high salt-fed rats of both sexes and improved with either Los or Enal.
    UNASSIGNED: Thus, inhibition of the RAS improves early changes in cardiac and renal histopathology in both sexes and albuminuria in male rats fed high fructose and high salt diet. Functional improvements in cardiorenal parameters may require longer treatment.
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  • 文章类型: Journal Article
    口服托吡酯治疗与全身不良反应相关,包括感觉异常,腹痛,和血浆水平的波动。本研究的目的是开发包含托吡酯聚合物纳米颗粒的基于鼻内原位凝胶的系统,并评估其在体外和体内的潜力。将通过纳米沉淀法制备的聚(乳酸-共-乙醇酸)(PLGA)纳米颗粒添加到泊洛沙姆407和HPMCK4M的原位胶凝体系中。选定的配方(TG5)的理化性质进行了评估,大鼠鼻腔渗透和体内药代动力学。PLGAnoparticles(O1)表现出低粒径(~144.4nm),良好的多分散性指数(0.202),负ζ电位(-12.7mV),和足够的包封效率(64.7%)。开发的原位凝胶显示理想的pH(6.5),良好的胶凝时间(35秒),胶凝温度(37℃),合适的粘度(1335cP)和药物含量96.2%。体外药物释放符合Higuchi释放动力学,表现出初始爆发释放和持续释放24小时的双相模式。对Sprague-Dawley大鼠(G3)口服给药显示出更高的血浆Cmax(504ng/ml,当与鼻内递送原位凝胶(G4)或溶液(G5)相比时,p<0.0001)。此外,G3的AUC0-α(8786.82ng/ml*h)明显高于其他组。当与G3相比时,脑摄取数据表明在12小时时G4(112.47ng/ml)具有更高的药物水平。组的组织病理学检查;G1(鼻内盐水),G2(鼻内安慰剂),G3、G4和G5未显示任何具有病理意义的病变。总的来说,观察到的实验结果是有希望的,并证实了开发的原位凝胶用于鼻内递送的潜力。
    Oral Topiramate therapy is associated with systemic adverse effects including paresthesia,abdominal pain, and fluctuations in plasma levels. The purpose of this research was to develop an intranasal in situ gel based system comprising Topiramate polymeric nanoparticles and evaluate its potential both in vitro and in vivo. Poly (lactic-co-glycolic acid) (PLGA)nanoparticles prepared by nanoprecipitation method were added into the in situ gelling system of Poloxamer 407 and HPMC K4M. Selected formulation (TG5) was evaluated for physicochemical properties, nasal permeation and in vivo pharmacokinetics in rats. PLGAnanoparticles (O1) exhibited low particle size (~ 144.4 nm), good polydispersity index (0.202), negative zeta potential (-12.7 mV), and adequate entrapment efficiency (64.7%). Developed in situ gel showed ideal pH (6.5), good gelling time (35 s), gelling temperature(37℃), suitable viscosity (1335 cP)and drug content of 96.2%. In vitro drug release conformedto Higuchi release kinetics, exhibiting a biphasic pattern of initial burst release and sustained release for 24 h. Oral administration of the drug to Sprague-Dawley rats (G3) showed higher plasma Cmax(504 ng/ml, p < 0.0001) when compared to nasal delivery of in situ gel (G4) or solution (G5). Additionally, AUC0-α of G3 (8786.82 ng/ml*h) was considerably higher than othergroups. Brain uptake data indicates a higher drug level with G4 (112.47 ng /ml) at 12 h when compared to G3. Histopathological examination of groups; G1 (intranasal saline), G2(intranasal placebo), G3, G4, and G5 did not show any lesions of pathological significance. Overall, the experimental results observed were promising and substantiated the potential of developed in situ gel for intranasal delivery.
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  • 文章类型: Journal Article
    In northern China, soil temperature slowly rises in spring, often subjecting apple roots to sub-low-temperature stress. Sugar acts as both a nutrient and signaling molecule in roots in response to low-temperature stress. To explore the effects of exogenous sugars on the growth and nutrient absorption of Malus baccata Borkh., we analyzed growth parameters, photosynthetic characteristics of leaves, and mineral element content in different tissues of M. baccata seedlings under five treatments, including control (CK), sub-low root zone temperature (L), sub-low root zone temperature + sucrose (LS), sub-low root zone temperature + fructose (LF), and sub-low root zone temperature + glucose (LG). The results showed that compared to CK, plant height, root growth parameters, aboveground biomass, leaf photosynthesis, fluorescence parameters, chlorophyll content, and the contents of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg) in M. baccata seedlings were significantly decreased under the L treatment, and the content of Ca in roots was significantly increased. Compared to the L treatment without exogenous sugar, photosynthesis, functional parameters, chlorophyll content, and growth parameters increased to different degrees after exogenous sucrose, fructose, and glucose application. The N and P contents in roots were significantly increased. The N, P, and K contents significantly increased in stems while only the Ca content significantly increased in stems treated with sucrose. Leaf N, P, K, Ca, and Mg contents significantly increased after being treated with the three exogenous sugars. In conclusion, exogenous sugars can improve photosynthetic efficiency, promote mineral element absorption, and alleviate the inhibition of growth and development of M. baccata at sub-low root zone temperatures, and the effect of sucrose treatment was better than that of fructose and glucose treatments.
    我国北方春季土温回升慢,常使苹果根系遭受亚低温胁迫。糖在根系响应低温胁迫过程中充当着营养成分和信号分子的双重功能。为探究不同外源糖对根区亚低温下山定子生长和养分吸收的影响,本试验设置对照(CK)、根区亚低温(L)、根区亚低温+蔗糖(LS)、根区亚低温+果糖(LF)和根区亚低温+葡萄糖(LG)5个处理,分析了山定子幼苗生长参数、叶片光合特性和不同组织矿质元素含量。结果表明:与CK相比,L处理后山定子株高、根系生长参数、地上部生物量、叶片光合和荧光参数及叶绿素含量均显著降低;除根系钙(Ca)含量显著升高外,山定子幼苗中的氮(N)、磷(P)、钾(K)、钙(Ca)和镁(Mg)含量均显著降低。与L处理相比,外源蔗糖、果糖和葡萄糖处理后,山定子叶片光合和荧光参数、叶绿素含量、生长参数均不同程度升高;根中N和P含量显著增加;茎中N、P和K含量显著增加,茎中Ca含量只在蔗糖处理后显著增加;叶中N、P、K、Ca和Mg含量均显著增加。综上,根区亚低温下外源糖处理可提高山定子叶片光合效率,促进矿质元素吸收,进而缓解根区亚低温对植株生长发育的抑制,且蔗糖处理效果好于果糖和葡萄糖处理。.
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  • 文章类型: Journal Article
    使用埃洛石粘土和维生素B1盐酸盐,已开发出一种新型的酸性埃洛石-树枝状聚合物催化复合材料,用于将果糖转化为5-羟基甲基糠醛。要在埃洛石上生长树枝状部分,它首先被官能化,然后与三聚氰胺反应,分别为表氯醇和维生素B1盐酸盐。然后,用ZnCl2处理所得复合物以提供路易斯酸位点。使用维生素B1作为离子液体的阳离子部分避免了使用有毒化学品并导致更环保的复合材料。同样,第2代的树枝状部分也接枝在埃洛石上,并研究了两种催化剂将果糖转化为5-羟基甲基糠醛的活性,以揭示树枝状聚合物生成的作用。对于最佳的催化复合材料,通过RSM对反应变量进行了优化,结果表明,在95°C下每0.1g果糖使用0.035g催化剂可在105分钟内以96%的产率提供HMF。营业额(TON)和频率(TOF)分别为10,130和5788h-1。动力学研究还强调Ea为22.85kJ/mol。热力学参数ΔH辛,ΔS#和ΔG#,计算为23kJ/mol,-129.2J/mol和72.14kJ/mol,分别。值得注意的是,该催化剂表现出良好的可回收性和热过滤批准的非均相催化性质。
    Using halloysite clay and vitamin B1 hydrochloride, a novel acidic halloysite-dendrimer catalytic composite has been developed for conversion of fructose to 5-hydroxymthylfurfural. To grow the dendritic moiety on halloysite, it was first functionalized and then reacted with melamine, epichlorohydrin and vitamin B1 hydrochloride respectively. Then, the resulting composite was treated with ZnCl2 to furnish Lewis acid sites. Use of vitamin B1 as the cationic moiety of ionic liquid obviated use of toxic chemicals and resulted in more environmentally friendly composite. Similarly, dendritic moiety of generation 2 was also grafted on halloysite and the activity of both catalysts for conversion of fructose to 5-hydroxymthylfurfural was investigated to disclose the role of dendrimer generation. For the best catalytic composite, the reaction variables were optimized via RSM and it was revealed that use of 0.035 g catalyst per 0.1 g fructose at 95 °C furnished HMF in 96% yield in 105 min. Turnover numbers (TONs) and frequencies (TOFs) were estimated to be 10,130 and 5788 h-1, respectively. Kinetic studies also underlined that Ea was 22.85 kJ/mol. The thermodynamic parameters of Δ H ≠ , Δ S ≠ and Δ G ≠ , were calculated to be 23 kJ/mol, - 129.2 J/mol and 72.14 kJ/mol, respectively. Notably, the catalyst exhibited good recyclability and hot filtration approved heterogeneous nature of catalysis.
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  • 文章类型: Journal Article
    Erythrinasubumbrans(Hassk)的树枝和根。Merr.据报道,通过降低α-葡萄糖苷酶和α-淀粉酶的活性而具有抗糖尿病活性。TNF-α是肥胖和糖尿病(DM)中的促炎细胞因子。它抑制胰岛素的作用,导致胰岛素抵抗。脂联素是一种在白色脂肪组织(WAT)中合成的抗炎肽,其高水平与DM风险降低有关。然而,有关ErythrinaSubumbrans(Hassk)的影响的信息。Merr.胰岛素抵抗仍然缺乏。
    为了获得E.subumbrans(Hassk)Merr的乙醇提取物的效果。叶(EES)在改善胰岛素抵抗条件。
    叶子是在Ciamis收集的,西爪哇,印度尼西亚,并使用96%的乙醇提取。通过进行胰岛素耐量试验(ITT)和评估血糖,在果糖诱导的成年雄性Wistar大鼠中研究了EES的作用。TNF-α,脂联素,FFA水平。还研究了脂肪组织的WAT和BAT的数量。用分光光度法测定EES中的总酚和黄酮,并使用LC-MS方法分析EES中槲皮素的存在。
    EES显著降低了%增重,TNF-α水平,果糖诱导的Wistar大鼠脂联素水平升高。EES可显着降低果糖诱导的Wistar大鼠的FFA水平,并显着影响类似于二甲双胍的BAT的形成。与未治疗的果糖诱导组(ITT=2.62±1.38)相比,较高的ITT值证明了EES和二甲双胍组的所有大鼠均改善了胰岛素抵抗(EES100mg/kgBW为3.01±0.91;EES200mg/kgBW为3.01±1.22;EES400mg/kgBW为5.86±3.13;二甲双胍为6.44±2.58)。EES含有多酚化合物(2.7638±0.0430mgGAE/g提取物),黄酮类化合物(1.9626±0.0152mgQE/g提取物),槲皮素0.246µg/mL,m/z301.4744。
    菊花(Hassk)。Merr.提取物在改善胰岛素抵抗状况方面的活性可能有进一步探索的潜力。然而,需要进一步的研究来证实其在缓解代谢紊乱中的作用。
    UNASSIGNED: The twigs and roots of Erythrina subumbrans (Hassk). Merr. Was reported to possess antidiabetic activity by reducing the activity of α-glucosidase and α-amylase. TNF-α is a pro-inflammatory cytokine in obesity and diabetes mellitus (DM). It inhibits the action of insulin, causing insulin resistance. Adiponectin is an anti-inflammatory peptide synthesized in white adipose tissue (WAT) and its high levels are linked with a decreased risk of DM. However, information about the effect of Erythrina subumbrans (Hassk). Merr. on insulin resistance are still lacking.
    UNASSIGNED: To obtain the effects of the ethanol extract of E. subumbrans (Hassk) Merr. leaves (EES) in improving insulin resistance conditions.
    UNASSIGNED: The leaves were collected at Ciamis, West Java, Indonesia, and were extracted using ethanol 96%. The effects of EES were studied in fructose-induced adult male Wistar rats by performing the insulin tolerance test (ITT) and assessing blood glucose, TNF-α, adiponectin, and FFA levels. The number of WAT and BAT of the adipose tissues was also studied. The total phenols and flavonoids in EES were determined by the spectrophotometric method and the presence of quercetin in EES was analyzed using the LC-MS method.
    UNASSIGNED: EES significantly reduced % weight gain, TNF-α levels, and increased adiponectin levels in fructose-induced Wistar rats. EES significantly reduced the FFA levels of fructose-induced Wistar rats and significantly affected the formation of BAT similar to that of metformin. All rats in EES and metformin groups improved insulin resistance as proven by higher ITT values (3.01 ± 0.91 for EES 100 mg/kg BW; 3.01 ± 1.22 for EES 200 mg/kg BW; 5.86 ± 3.13 for EES 400 mg/kg BW; and 6.44 ± 2.58 for metformin) compared with the fructose-induced group without treatment (ITT = 2.62 ± 1.38). EES contains polyphenol compounds (2.7638 ± 0.0430 mg GAE/g extract), flavonoids (1.9626 ± 0.0152 mg QE/g extract), and quercetin 0.246 µg/mL at m/z 301.4744.
    UNASSIGNED: Erythrina subumbrans (Hassk). Merr. extract may have the potential to be further explored for its activity in improving insulin resistance conditions. However, further studies are needed to confirm its role in alleviating metabolic disorders.
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  • 文章类型: Journal Article
    糖的消耗增加了许多寄生黄蜂(类寄生虫)的繁殖力和寿命,但是这些昆虫是否使用糖从头合成大量的脂肪酸和储存脂肪(脂肪生成)却引起争议。长期以来,人们一直认为寄生黄蜂在进化过程中失去了这种能力,主要是因为在几个物种中,随意获得糖的黄蜂并没有增加teneral脂质水平。最近的研究表明,许多物种仍然能够从葡萄糖从头合成脂肪酸。不清楚,然而,其他糖是否也用于脂肪酸生物合成,以及糖浓度增加到天然糖源中的水平是否转化为更高的脂肪酸产量。此外,有人认为,与增加teneral脂肪储备的物种(如果蝇)相比,类寄生虫中的脂肪酸产量可以忽略不计。在这里,我们通过稳定的同位素标记实验表明,Nasoniavitripennis的雌性转化D-葡萄糖,D-果糖,蔗糖,α,α-海藻糖,自然界中成年寄生虫消耗的主要糖,与棕榈酸一样好,硬脂酸,油酸,和亚油酸.来自D-半乳糖的脂肪生成也发生,尽管程度较低。糖浓度对于脂肪生成活性至关重要,并且几乎80%的从头合成的脂肪酸被掺入到储存脂肪中(三酰甘油酯)。与D.melanogaster在48小时摄食期内脂肪酸生物合成的比较表明,硫酸N.vitripennis每单位体重产生的脂肪酸大约是其一半。两种物种都喂食等量的葡萄糖。我们得出的结论是,在黄质脂质储备耗尽时,脂肪生成远非微不足道,并且对能量平衡起着重要作用。
    Sugar consumption increases the fecundity and longevity in many species of parasitic wasps (parasitoids) but whether these insects use sugars to synthesize significant amounts of fatty acids and storage fat de novo (lipogenesis) is discussed controversially. It has long been assumed that parasitic wasps lost this ability during evolution, mainly because in several species wasps with ad libitum access to sugar did not increase teneral lipid levels. Recent studies demonstrated that many species are nonetheless capable of synthesizing fatty acids de novo from glucose. It is unclear, however, whether also other sugars are used for fatty acid biosynthesis and whether an increase of sugar concentration to levels occurring in natural sugar sources translates into higher fatty acid production. Furthermore, it has been suggested that fatty acid production in parasitoids is negligible compared to species increasing teneral fat reserves such as Drosophila melanogaster. Here we show by stable isotope labeling experiments that females of Nasonia vitripennis convert D-glucose, D-fructose, sucrose, and α,α-trehalose, major sugars consumed by adult parasitoids in nature, equally well to palmitic, stearic, oleic, and linoleic acid. Lipogenesis from D-galactose occurs as well albeit to a lesser extent. Sugar concentration is crucial for lipogenic activity, and almost 80% of de novo synthesized fatty acids were incorporated into storage fat (triacylglycerides). Comparison of fatty acid biosynthesis within a 48-h feeding period with D. melanogaster revealed that N. vitripennis produced approximately half as many fatty acids per body mass unit. Both species fed equal amounts of the glucose offered. We conclude that lipogenesis is far from negligible in N. vitripennis and plays an important role for the energy balance when teneral lipid reserves deplete.
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  • 文章类型: Journal Article
    胰岛素抵抗,高果糖消耗诱导,对认知功能产生负面影响。硝苯地平可用于神经系统疾病。这项研究旨在评估硝苯地平与正常饮食(ND)或生酮饮食(KD)在认知功能障碍中的作用。雄性Wistar大鼠在饮用水中接受10%果糖8周以诱导胰岛素抵抗。大鼠随后接受硝苯地平(5.2mg/kg/天;p.o.)和ND或KD再接受五周。单向和双向ANOVAs用于分析数据。恢复到ND改善了胰岛素抵抗和血脂,除了脑源性神经营养因子(BDNF),糖原合成酶激酶-3β(GSK3β),和胰岛素降解酶(IDE)水平。单独饲喂KD的大鼠和接受硝苯地平与KD的大鼠在先前提到的参数中没有显示出与ND组相似的改善。然而,硝苯地平-ND大鼠的认知行为和胰岛素抵抗均有改善。硝苯地平-KD改善GSK3β治疗,淀粉样β(Aβ),和tau蛋白水平。硝苯地平-KD组合成功减少了积累的Aβ和tau蛋白,由于其副作用,KD可能会使用一段时间,然后硝苯地平治疗可以继续与ND。该结论是基于这样的发现,即这种组合减轻了胰岛素抵抗并改善了相关的行为。
    Insulin resistance, induced by high fructose consumption, affects cognitive function negatively. Nifedipine may be suggested for neurological disorders. This study aimed to assess the effect of nifedipine with either a normal diet (ND) or a ketogenic diet (KD) in cognitive dysfunction. Male Wistar rats received 10% fructose in drinking water for 8 weeks to induce insulin resistance. Rats received nifedipine (5.2 mg/kg/day; p.o.) later with ND or KD for an additional five weeks. One and two-way ANOVAs were used in analyzing the data. Reversion to the ND improved insulin resistance and lipid profile, besides brain-derived neurotrophic factor (BDNF), glycogen synthase kinase-3 beta (GSK3β), and insulin-degrading enzyme (IDE) levels. Rats fed KD alone and those that received nifedipine with KD did not show similar improvement in the previously mentioned parameters as the ND group. However, nifedipine-ND rats showed improvement in cognitive behavior and insulin resistance. Treatment with nifedipine-KD ameliorated GSK3β, amyloid β (Aβ), and tau protein levels. As the nifedipine-KD combination succeeded in diminishing the accumulated Aβ and tau protein, KD may be used for a while due to its side effects, then nifedipine treatment could be continued with an ND. This conclusion is based on the finding that this combination mitigated insulin resistance with the associated improved behavior.
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  • 文章类型: Journal Article
    背景:我们研究了加兰他敏在果糖超负荷大鼠后代中与早期心脏代谢功能障碍相关的自主神经功能障碍中的作用。
    方法:Wistar大鼠在交配前接受在饮用水(10%)或水中稀释的果糖60天。果糖超负荷一直维持到泌乳结束。对照和果糖超负荷动物的后代(出生后21天)分为三组:对照组(C),果糖(F)和果糖+加兰他敏(GAL)。口服给予GAL(5mg/kg)直至后代51天龄。代谢,评估了血液动力学和心血管自主神经调节。
    结果:与C和GAL组相比,F组显示胰岛素耐量(KITT)降低。F组,与C组相比,动脉血压升高,心率和交感神经平衡(LF/HF比)和低频段收缩压(LF-SAP)。GAL组,与F组相比,显示阴道介导的RMSSD指数增加,高频段(HF-PI)和降低的LF/HF比率以及SAP(VAR-SAP)和LF-SAP的方差。HF-PI和KITT之间存在相关性(r=0.60),心率(r=-0.65)和MAP(r=-0.71)。
    结论:GAL治疗显著改善心血管自主神经调节,这与长期摄入果糖的父母后代的心脏代谢功能障碍的改善有关。
    BACKGROUND: We investigate the role of galantamine on autonomic dysfunction associated with early cardiometabolic dysfunction in the offspring of fructose-overloaded rats.
    METHODS: Wistar rats received fructose diluted in drinking water (10%) or water for 60 days prior to mating. Fructose overload was maintained until the end of lactation. The offspring (21 days after birth) of control and fructose-overloaded animals were divided into three groups: control (C), fructose (F) and fructose + galantamine (GAL). GAL (5 mg/kg) was administered orally until the offspring were 51 days old. Metabolic, hemodynamic and cardiovascular autonomic modulation were evaluated.
    RESULTS: The F group showed decreased insulin tolerance (KITT) compared to the C and GAL groups. The F group, in comparison to the C group, had increased arterial blood pressure, heart rate and sympathovagal balance (LF/HF ratio) and a low-frequency band of systolic arterial pressure (LF-SAP). The GAL group, in comparison to the F group, showed increased vagally mediated RMSSD index, a high-frequency band (HF-PI) and decreased LF/HF ratio and variance in SAP (VAR-SAP) and LF-SAP. Correlations were found between HF-PI and KITT (r = 0.60), heart rate (r = -0.65) and MAP (r = -0.71).
    CONCLUSIONS: GAL treatment significantly improved cardiovascular autonomic modulation, which was associated with the amelioration of cardiometabolic dysfunction in offspring of parents exposed to chronic fructose consumption.
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