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101.
102.
Ivan Zanyatkin Yulia Stroylova Sofia Tishina Victor Stroylov Aleksandra Melnikova Thomas Haertle Vladimir Muronetz 《Phytotherapy research : PTR》2017,31(7):1046-1055
Neurodegenerative diseases are associated with accumulation of amyloid‐type protein misfolding products. Prion protein (PrP) is known for its ability to aggregate into soluble oligomers that in turn associate into amyloid fibrils. Preventing the formation of these infective and neurotoxic entities represents a viable strategy to control prion diseases. Numerous attempts to find dietary compounds with anti‐prion properties have been made; however, the most promising agent found so far was curcumin, which is poorly soluble and merely bioavailable. In the present work, we identify 3,4‐dimethoxycinnamic acid (DMCA) which is a bioavailable coffee component as a perspective anti‐prion compound. 3,4‐Dimethoxycinnamic acid was found to bind potently to prion protein with a Kd of 405 nM. An in vitro study of DMCA effect on PrP oligomerization and fibrillization was undertaken using isothermal titration calorimetry (ITC), dynamic light scattering (DLS) and circular dichroism (CD) methodologies. We demonstrated that DMCA affects PrP oligomer formation reducing the oligomer content by 30–40%, and enhancing SH‐SY5Y cell viability treated with prion oligomers. Molecular docking studies allowed to suggest a site where DMCA is able to bind stabilizing PrP tertiary structure. We suggest that DMCA is a perspective dietary compound for prophylaxis of neurodegenerative diseases that needs further research. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
103.
目的研究薄荷Mentha haplocalyx在大鼠体内的入血成分及代谢产物。方法采用超高效液相色谱-飞行时间质谱(UHPLC-Q-TOF-MS/MS)联用技术鉴定薄荷入血成分及代谢产物。采用Eclipse Plus C18色谱柱(100 mm×4.6 mm,3.5μm),流动相为0.1%甲酸水溶液(A)-乙腈(B),梯度洗脱,体积流量0.3 m L/min,进样量5μL。结果建立了大鼠给药后血浆样品的分析测定方法,并且与空白生物样品、薄荷提取物和对照品的保留时间及质谱离子碎片信息对比,共鉴定了28个入血原型成分、39个代谢产物,其中1个为未曾报道过的木犀草素的新代谢产物。结论薄荷在大鼠体内的代谢途径包括氧化、还原、甲基化、硫酸酯化、葡萄糖醛酸化等,其中以II相反应为主。所建立的方法简单可靠,为揭示薄荷的药效物质基础提供理论依据。 相似文献
104.
目的研究西红花水提液ig给予大鼠后的入血成分,初步揭示西红花体内潜在药效物质基础及主要入血成分的体内代谢过程。方法对照西红花ig给药前后的HPLC图谱,采用HPLC-DAD-ESI-MSn鉴定吸收入血成分及随时间变化规律。结果西红花中11个主要化学成分被鉴定,大鼠ig给药后发现4个吸收入血成分,包括1个原型成分和3个代谢产物,其中苦藏花素以原型入血。《中国药典》西红花质量评价指标西红花苷-I和西红花苷-II,在所有时间点的血浆中均未发现,而检测到的是西红花苷类化合物的代谢产物(西红花酸和西红花酸单葡萄糖醛酸结合物)。苦藏花素吸收入血后60 min达峰值,而西红花苷的代谢产物西红花酸在30、120 min出现"双峰"现象。结论吸收入血的苦藏花素和西红花苷的代谢产物可能是西红花体内发挥药效的潜在物质基础。该研究为更合理地选择西红花质量评价指标、完善西红花质量控制标准提供参考,也为进一步系统研究西红花体内药动学行为提供了理论基础。 相似文献
105.
Juan Wang Jian-li Li Jing Li Jin-xin Li Shu-jie Liu Lu-qi Huang Wen-yuan Gao 《中草药(英文版)》2017,9(2):115-125
Over past decades plant tissue culture has emerged as an alternative of whole plant cultivation in the production of valuable secondary metabolites.Adventitious roots culture of Panax ginseng and Echinacea purpure has reached the scale of 1-10 kL.Some molecular biological techniques,such as transgenic technology and genetic stability are increasingly used in the studies on plant tissue cultures.The studies on elicitors have deepened into the induction mechanism,including signal molecules,functional genes,and so on.More and more biological elicitors,such as A.niger and yeast are used to increase the active compounds in plant tissue cultures.We also discussed the application of synthetic biology in the studies on biosynthesis of artemisinin,paclitaxel,and tanshinon.The studies on active ingredients biosynthesis of medicinal plants provide unprecedented possibilities to achieve mass production of active ingredients.Plant tissue cultures can not only produce active ingredients but also as experimental materials for biosynthesis.In order to improve the contents of active compounds in medicinal plants,following aspects could be carried out gene interference or gene silencing,gene overexpression,combination with chemical synthesis,application of elicitors,and site-directed mutagenesis of the key enzymes. 相似文献
106.
107.
型糖尿病伴认知功能损伤小鼠脑组织肠道菌群代谢物的改变 《首都医科大学学报》2022,43(4):622-629
目的 探讨在发生认知功能损伤的1型糖尿病(type 1 diabetes mellitus,T1DM)小鼠脑组织中肠道菌群代谢物的变化。方法 选取20只6周龄C57BL/6小鼠,适应性喂养1周后采用数字表法随机分为对照组(Control组,n=10)和1型糖尿病模型组(DM组,n=10)进行处理。采用链脲佐菌素(streptozotocin,STZ)诱导T1DM小鼠,造模成功8周后进行Morris水迷宫检测,随后收集小鼠脑组织采用宏代谢组学检测肠道菌群代谢产物,并分析差异代谢物以及代谢通路。结果 STZ腹腔注射后8周DM组小鼠空间学习和记忆能力明显受损,表现为Morris水迷宫中逃避潜伏期显著增加(P<0.001),平均游泳距离显著增加(P=0.001),目的象限所在时间(P=0.043)和穿越平台次数显著减少(P=0.004)。采用宏代谢组学鉴定了脑组织中123种肠道菌群代谢物并发现了谷氨酰胺(Log2FC=0.262,P=0.002)、酒石酸(Log2FC=0.847,P=0.017)、乳酸(Log2FC=0.326,P=0.002)和间氨基苯甲酸(Log2FC=1.028,P=0.046)、3-氨基异丁酸(Log2FC=-1.466,P=0.049)、葡萄糖酸内酯(Log2FC=-0.796,P=0.043)和苏糖酸(Log2FC=-0.310,P=0.042)、吲哚乳酸(Log2FC=-1.252,P=0.030)、酮亮氨酸(Log2FC=-0.922,P=0.040)、3-羟基丁酸(Log2FC=-0.372,P=0.009)以及肉豆蔻酸(Log2FC=-0.563,P=0.035)11种显著差异代谢物,涉及14个主要相关代谢通路,包括嘧啶代谢、氨基酸代谢、糖代谢、短链脂肪酸代谢等。结论 DM小鼠脑组织中多种肠道菌群代谢物水平发生显著变化,靶向肠道菌群及其相关代谢通路有望成为治疗T1DM诱导的认知功能障碍的有效策略。 相似文献
108.
Zhan Yali Wang Xiaohe Wang Deguang Zhang Sen Wan Yang Wu Jifeng Xie Shengxue Hao Li 《中华肾脏病杂志》2018,34(3):179-184
Objective To analyze the correlation between the pathological types of parathyroid and clinical manifestations in patients with renal secondary hyperparathyroidism (SHPT), so as to improve the efficacy and safety of treatment. Methods The pathological and clinical data of 130 patients with renal SHPT and maintenance hemodialysis (MHD) who had undergone total parathyroidectomy with autotransplantation (TPTX+AT) were collected. A total of 545 parathyroid glands were obtained and 998 slices were made and read. According to the pathological types of parathyroid hyperplasia, the patients were divided into diffuse hyperplasia (DH) group, diffuse between hyperplasia and nodular hyperplasia (DH/NH) group as well as nodular hyperplasia (NH) group. The clinical and biochemical characteristics of different groups before and after operation (1-, 3-, 6-, 9-, 12-month) were compared and analyzed by statistical tests. Results (1) The preoperative status: the dialysis age, serum calcium as well as incidence of bone pain, skin itching and shorten height in the NH group were significantly higher than those in the DH group (all P<0.05), and the serum phosphorus and iPTH in the NH group were significantly higher than those in DH and DH/NH group (all P<0.05). (2) The postoperative status: the serum calcium of the NH group at 1-month was lower than that of the DH group, and the incidence of hypocalcemia of the NH group at 1-month was higher than that of the DH group (P<0.05); the serum phosphorus at 3-, 6-, 9-month and iPTH at 1-, 3-month of the NH group were significantly lower than that of the DH group (all P<0.05), and the serum phosphorus at 3-month and iPTH at 1-month of the NH group were lower than that of the DH/NH group (all P<0.05). Among the 3 groups the serum phosphorus change from 1 to 12 months had difference (F=3.241, P=0.042), while the differences of serum calcium and iPTH changes were statistically insignificant. Conclusions The clinical manifestations, serum calcium, phosphorus and iPTH in patients with renal SHPT before and after TPTX+AT are closely related to the pathological types of parathyroid hyperplasia. Compared with the DH patients, before the operation the NH patients have longer dialysis age, more serious the clinical symptoms such as bone disease, higher calcium, phosphorus and iPTH, while greater reduction of the serum calcium, phosphorus and iPTH in the short term after operation. 相似文献
109.
Wang Mengjing Huang Bihong Tao Ye Zhang Weichen Chen Weisheng Huang Junwen Wang Hongying Zhang Minmin Chen Jing. 《中华肾脏病杂志》2018,34(12):909-916
Objective To observe the effects of three treatment methods on renal anemia in maintenance hemodialysis patients with hyperparathyroidism secondary to uremia and analyze the influencing factors of erythropoietin (EPO) dosage. Methods A total of 55 maintenance hemodialysis patients with secondary hyperparathyroidism at the hemodialysis center of Huashan Hospital affiliated to Fudan University from January 2015 to December 2016 were retrospectively divided into three groups according to different treatment methods, parathyroidectomy +forearm transplantation group (surgery group, n=16), cinacalcet treatment group (n=6), and calcitriol treatment group (n=33), respectively. The hemoglobin level and erythropoietin dosage were measured before treatment and in the 3rd month, the 6th month and the 12th month after treatment. The changes of hemoglobin and erythropoietin dosage in the three groups before and after treatment were observed, and the mixed effect model was used to analyze the difference of the change of hemoglobin and erythropoietin dosage among three groups. Multiple linear regression analysis was used to analyze the influencing factors of EPO dosage after one year. Results The levels of intact parathyroid hormone (iPTH) in the surgery group and the cinacalcet group before treatment were significantly higher than that in the calcitriol group (both P<0.05). In the 12th month after treatment, the levels of iPTH decreased significantly in the patients of surgery group and the cinacalcet group compared with those before treatment (both P<0.05). The levels of serum alkaline phosphatase, serum calcium and serum phosphorus in the surgery group also decreased significantly compared with those before treatment (all P<0.05). The mixed effect model analysis showed that the hemoglobin level of surgery group was on an upward trend after the treatment, and the overall level was significantly higher than cinacalcet and calcitriol treatment group (P=0.007). There was no significant difference in the dosage change of erythropoietin (EPO) in the three groups over time. However, the intra-group comparison of the mixed effect model showed that the dosage of EPO in the 12th month was significantly lower than that of before the treatment in surgery group (P=0.007). Multiple linear regression analysis showed that dialysis vintage (B=-0.064, P=0.012) and ferritin ≥ 500 μg/L (B=0.645, P=0.032) were independent influencing factors of EPO dosage. The longer the dialysis vintage, the less EPO dosage, and more EPO dosage were observed in patients with ferritin ≥ 500 μg/L. Conclusions Parathyroidectomy and forearm transplantation is more effective in reducing EPO dosage and improving renal anemia in maintenance hemodialysis patients with secondary hyperparathyroidism. Dialysis vintage and ferritin are independent influencing factors for the dosage of EPO. 相似文献
110.
肠道内庞大的菌群之间相互依存、相互制约,协同参与机体生理代谢和营养物质的消化。肠道菌群与心血管健康相关研究已成为十分重要的研究领域,肠道菌群组成的改变、肠道菌群产生的代谢产物和毒素都能引发心血管系统的病变。心血管疾病(cardiovascular disease,CVD)因高发病率和死亡率已成为一个主要的健康问题,CVD的发生、发展中肠道特定菌群的改变已被确定为疾病发生的关键因素。然而,肠道菌群及其代谢产物如何产生及影响CVD的潜在机制仍不清楚。本文就肠道菌群通过肠心轴调节CVD的最新研究进展进行综述,重点总结肠道微生物及其代谢产物与CVD发生发展之间复杂的相互作用,以及肠道菌群失调的改变对心血管事件发生的影响,探讨肠道菌群与CVD发病机制之间的因果联系。 相似文献