离子交换－比色法测定杞菊地黄丸中甜菜碱含量

杞菊地黄丸水提取物依次通过强阳离子交换树脂柱、强阴离子交换树脂柱分离得到甜菜碱（Ｂａｔａｉｎｅ），然后与雷氏盐形成沉淀，沉淀用７００ｇ／Ｌ丙酮溶解，用比色法在λｍａｘ５２５ｎｍ处测定其含量，两个厂家生产的杞菊地黄丸中甜菜碱的含量分别为０．０６６％，０．０７４％，平均回收率为９７．００％，相对标准差为０．８３％，相关系数为０．９９９８．     

五子衍宗丸质量标准的研究

目的：建立五子衍宗丸(枸杞子，菟丝子，覆盆子，五味子和车前子)的质量标准。方法：采用双波长薄层扫描法对五子衍宗丸中指标性成分甜菜碱进行定量分析，λs=514nm，λR=468nm；同时对制剂中其他主要药味菟丝子、五味子进行薄层鉴别。结果：平均回收率为99．28％，RSD=2．66％(n=5)。结论：所建方法可靠、准确、专属性强，本法可有效控制五子衍宗丸的质量。     

盐酸甜菜碱对缺氧小鼠的保护作用

盐酸甜菜碱(betaine hydrochloride,BTH)是枸杞、牛膝等中药的活性成分,已能化学合成.BTH具有表面活性剂作用,对大肠杆菌、金黄色葡萄球菌、白色念珠菌等具有杀灭作用.在体内具有甲基供体作用,能促进脂肪代谢,具有抗脂肪肝、保护肾脏、降血压、抗肿瘤、缓和应激、增进食欲等药理作用,可用于胃酸缺乏、动脉粥样硬化、肝脏疾病、止痛、风湿病、糖尿病等的治疗,也可用作饲料添加剂[1～4].本文观察了BTH对缺氧小鼠模型的保护作用.     

Impact of intratumoral heterogeneity of breast cancer tissue on quantitative metabolomics using high‐resolution magic angle spinning 1H NMR spectroscopy

High‐resolution magic angle spinning (HR MAS) nuclear magnetic resonance (NMR) spectroscopy is increasingly being used to study metabolite levels in human breast cancer tissue, assessing, for instance, correlations with prognostic factors, survival outcome or therapeutic response. However, the impact of intratumoral heterogeneity on metabolite levels in breast tumor tissue has not been studied comprehensively. More specifically, when biopsy material is analyzed, it remains questionable whether one biopsy is representative of the entire tumor. Therefore, multi‐core sampling (n = 6) of tumor tissue from three patients with breast cancer, followed by lipid (0.9‐ and 1.3‐ppm signals) and metabolite quantification using HR MAS ¹H NMR, was performed, resulting in the quantification of 32 metabolites. The mean relative standard deviation across all metabolites for the six tumor cores sampled from each of the three tumors ranged from 0.48 to 0.74. This was considerably higher when compared with a morphologically more homogeneous tissue type, here represented by murine liver (0.16–0.20). Despite the seemingly high variability observed within the tumor tissue, a random forest classifier trained on the original sample set (training set) was, with one exception, able to correctly predict the tumor identity of an independent series of cores (test set) that were additionally sampled from the same three tumors and analyzed blindly. Moreover, significant differences between the tumors were identified using one‐way analysis of variance (ANOVA), indicating that the intertumoral differences for many metabolites were larger than the intratumoral differences for these three tumors. That intertumoral differences, on average, were larger than intratumoral differences was further supported by the analysis of duplicate tissue cores from 15 additional breast tumors. In summary, despite the observed intratumoral variability, the results of the present study suggest that the analysis of one, or a few, replicates per tumor may be acceptable, and supports the feasibility of performing reliable analyses of patient tissue.     

甜菜碱对大鼠肝纤维化的保护作用研究

目的观察甜菜碱对复合致病因素诱导肝纤维化大鼠的保护作用。方法复合致病因素法诱导制备肝纤维化大鼠模型,观察灌服甜菜碱对肝纤维化大鼠血清丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)、内毒素(ET)、同型半胱氨酸(Hcy)、透明质酸(HA)、层粘连蛋白(LN)、IV胶原蛋白(IV-C)、Ⅲ型前胶原蛋白(PC-Ⅲ)及肝组织肿瘤坏死因子α(TNF-α)、一氧化氮(NO)、过氧亚硝酸盐阴离子(ONOO-)、丙二醛(MDA)的变化,并采用HE和VG染色分别观察肝损伤和肝纤维化情况。结果大鼠肝纤维化模型复制成功。给与三个剂量的甜菜碱后,肝组织病理损伤改善。反映大鼠肝功能(ALT、AST)及肝纤维化指标(HA、LN、IV-C)的水平不同程度降低。血清内毒素、肝组织NO、MDA水平亦明显降低。同时Hcy及ONOO-在中、高剂量组明显降低,而TNF-α的降低在高剂量组中也具有明显的统计学差异。结论甜菜碱可抑制复合因素诱导的大鼠肝纤维化,其作用可能是通过降低大鼠体内高同型半胱氨酸、调节炎性细胞因子和氧化应激实现的。     

Radioactive choline metabolism in guinea pig gallbladder

Acetylcholine may be released from gallbladder intrinsic nerves in response to cholecystokinin stimulation. This study characterized metabolites of [¹⁴C]choline produced in the gallbladder and released during incubation, with or without cholecystokinin-octapeptide. Radiolabeled [¹⁴C]choline was applied to the mucosal or muscle surface of intact guinea pig gallbladders in an organ bath. After radiolabeling, gallbladders were incubated with or without the contractile agonist cholecystokinin-octapeptide. Metabolites of [¹⁴C]choline were identified in gallbladder tissue and incubation buffers using HPLC and thin-layer chromatography. The major metabolites of [¹⁴C]choline were betaine and phosphocholine. [¹⁴C]Phosphocholine was incorporated slowly into [¹⁴C]phosphatidylcholine. [¹⁴C]Choline was released into buffers during incubation. [¹⁴C]Acetylcholine constituted less than 1% of radiolabel in the gallbladder. There was no identifiable [¹⁴C]acetylcholine released in buffers. Cholecystokinin-octapeptide did not affect choline metabolism. These studies showed that choline in the gallbladder is metabolized along pathways similar to those in the liver. Gallbladders released mostly choline, rather than acetylcholine, even during hormonally induced contraction.This project was supported by the Research and Development Office of the Department of Veterans Affairs.     

Role of betaine in liver injury induced by the exposure to ionizing radiation

Oxidative stress, apoptosis, and fibrosis may play a major role in the development of radiation‐induced liver damage. Betaine, a native compound widely present in beetroot, was reported to possess hepato‐protective properties. The objective of this study was to investigate the influence of betaine on radiation‐induced liver damage. Animals were exposed to 9 Gy applied in 3 doses of 3 Gy/wk. Betaine (400 mg/kg/d), was orally supplemented to rats after the first radiation dose, and daily during the irradiation period. Animals were sacrificed 1 day after the last dose of radiation. The results showed that irradiation has induced oxidative stress in the liver denoted by a significant elevation in malondialdehyde, protein carbonyl, and 8‐hydroxy‐2‐deoxyguanosine with a significant reduction in catalase activity and glutathione (GSH) content. The activity of the detoxification enzyme cytochrome P450 (CYP450) increased while GSH transferase (GSH‐T) decreased. The activity of the apoptotic marker caspase‐3 increased concomitant with increased hyaluronic acid, hydroxyproline, laminin (LN), and collagen IV. These alterations were associated with a significant increase of gamma‐glutamyl transferase, alkaline phosphatase and alanine and aspartate aminotransferase markers of liver dysfunction. Betaine treatment has significantly attenuated oxidative stress, decreased the activity of CYP450, enhanced GSH‐T, reduced the activity of caspase‐3, and the level of fibrotic markers concomitant with a significant improvement of liver function. In conclusion, betaine through its antioxidant activity and by enhancing liver detoxification and reducing apoptosis may alleviate the progression of liver fibrosis and exert a beneficial impact on radiation‐induced liver damage.     

One-Carbon Metabolism in Alzheimer’s Disease and Parkinson’s Disease Brain Tissue

Disruptions in one-carbon metabolism and elevated homocysteine have been previously implicated in the development of dementia associated with Alzheimer’s disease (AD) and Parkinson’s disease (PD). Moreover, a PD diagnosis itself carries substantial risk for the development of dementia. This is the first study that explores alterations in one-carbon metabolism in AD and PD directly in the human brain frontal cortex, the primary center of cognition. Applying targeted liquid chromatography–tandem mass spectrometry (LC-MS/MS), we analyzed post-mortem samples obtained from 136 subjects (35 AD, 65 PD, 36 controls). We found changes in one-carbon metabolites that indicate inefficient activation of cystathionine β-synthase (CBS) in AD and PD subjects with dementia, the latter seemingly accompanied by a restricted re-methylation flow. Levodopa–carbidopa is known to reduce available vitamin B6, which would explain the hindered CBS activity. We present evidence of temporary non-protein-bound homocysteine accumulation upon levodopa intake in the brain of PD subjects with dementia but not in non-demented PD subjects. Importantly, this homocysteine elevation is not related to levodopa dosage, disease progression, or histopathological markers but exclusively to the dementia status. We hypothesize that this levodopa-induced effect is a direct cause of dementia in PD in susceptible subjects with reduced re-methylation capacity. Furthermore, we show that betaine best correlates with cognitive score even among PD subjects alone and discuss nutritional recommendations to improve one-carbon metabolism function.     

甜菜碱促进小鼠脾淋巴细胞增殖作用的钙通道机制研究

目的:研究甜菜碱促进小鼠脾淋巴细胞的增殖作用与钙通道的关系.方法:采用清洁级BALB/c小鼠分离小鼠脾淋巴细胞后体外培养的方式获得小鼠脾淋巴细胞,分为阴性对照组、Con A组、甜菜碱0.04,0.4,4,20 mmol·L~(-1)组.分别采用MTT法观察甜菜碱对小鼠脾淋巴细胞增殖的作用,流式细胞术测定甜菜碱对小鼠脾淋巴细胞周期的变化,激光共聚焦扫描显微镜观察甜菜碱对小鼠脾淋巴细胞内钙浓度的变化及加入不同钙通道阻滞剂后细胞内钙浓度的变化.结果:4,20 mmol·L~(-1)甜菜碱体外作用于小鼠脾淋巴细胞12 h促进小鼠脾淋巴细胞增殖,0.04,0.4,4,20 mmol·L~(-1)甜菜碱分别体外作用于小鼠脾淋巴细胞24,48 h均促进小鼠脾淋巴细胞增殖,以4 mmol·L~(-1)甜菜碱作用24 h效果最好;4 mmol·L~(-1)甜菜碱作用小鼠脾淋巴细胞4,6,18,24 h能促使小鼠脾淋巴细胞由G_0/G_1期进入S期,并以18 h效果最为明显;4 mmol·L~(-1)甜菜碱作用于淋巴细胞6,12,18 h,脾淋巴细胞内Ca~(2+)浓度明显升高(P＜0.01),以6 h效果最明显;钙通道阻滞剂硝苯地平、地尔硫卓、咪贝地尔、金雀异黄素对甜菜碱升高小鼠脾淋巴细胞内钙离子浓度没有影响,而维拉帕米、新霉素、肝素、普鲁卡因能阻断甜菜碱升高小鼠脾淋巴细胞内钙离子浓度.结论:甜菜碱通过升高小鼠脾淋巴细胞内钙离子浓度而促进小鼠脾淋巴细胞由G_0/G_1期进入S期,促小鼠脾淋巴细胞增殖的作用.细胞内钙离子浓度升高主要通过2个途径:影响G蛋白介导的L-型电压门控钙通道的α_1亚单位而引起外钙内流;影响胞内钙库的IP_3R钙通道和RyR钙通道而引起内钙释放.