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1.
The antiradical activity (ARA) of fresh squeezed juices and those reconstituted from concentrate was examined in reactions with diphenylpicrylhydrazyl (DPPH). Fresh squeezed juices contain a higher amount of phenolic substances and exhibit stronger ARA. The maximum ARA among the studied fruit juices was observed for orange and grapefruit juices. The ability to discolor aqueous EtOH solutions of DPPH can be used as a test for primary quantitative evaluation of the ARA of fruit juices.  相似文献   

2.
Acid-reducing agents (ARAs) are the most commonly used medicines to treat patients with gastric acid-related disorders. ARA administration results in an elevation of intragastric pH and eases symptoms such as acid reflux. However, this effect could also lead to a reduction in the absorption of some co-administered oral medications (i.e. weakly basic drugs) by decreasing their gastric solubility. This in turn can result in a significant reduction of the efficacy of the co-administered oral medications. In order to address this problem, substantial efforts in translational modeling and the development of predictive in-vitro assays to better forecast the effect of ARA on oral absorption are conducted in the pharmaceutical industry. Despite these efforts, it remains challenging to predict the impact of ARAs on co-administered drugs. In this study, we evaluated the utility of Triskelion's Gastro-Intestinal Model (Tiny-TIM) in predicting ARA effect on twelve model drugs whose in-vivo data are available. The Tiny-TIM prediction of the ARA effect matched the observed effect of ARA co-administration in humans for the 12 model compounds. In summary, Tiny-TIM is a very reliable and promising GI model to successfully predict the nature of DDI when ARAs are co-administered with the drug of interest.  相似文献   

3.
BackgroundEarly assessment of pH-dependent drug-drug-interactions (DDIs) for salts of poorly soluble weakly acidic compounds offers various advantages for patient safety, the pharmaceutical industry, and regulatory bodies. Biorelevant media and tests reflecting physiological changes during acid-reducing agent (ARA) co-administration can be used to explore and predict the extent of the pH effect during therapy with ARAs.MethodsSolubility, one-stage and two-stage dissolution of tablets containing potassium raltegravir, the marketed salt form of this poorly soluble, weakly acidic drug, was investigated using biorelevant media specially designed to reflect administration without and during ARA co-therapy. The dissolution data were then converted into parameters suitable for input into an in silico model (Simcyp?) and the simulated plasma profiles were compared with available pharmacokinetic (PK) data from the literature.ResultsDissolution of the potassium raltegravir formulation in media reflecting ARA co-administration, and thus elevated gastric pH, was faster and more complete than in experiments reflecting the low gastric pH observed in the absence of ARA co-administration. Simulations using data from dissolution experiments with ARA media appropriately bracketed the in vivo data for ARA co-administration in healthy volunteers.ConclusionDissolution data from in vitro experiments in biorelevant media reflecting physiological changes due to ARA co-administration provide valuable information about potassium raltegravir's behavior during concomitant ARA therapy. The approach may also be suitable for salts forms of other poorly soluble, weakly acidic drugs.  相似文献   

4.
Arachidonic acid oil (ARA-oil) derived from the fungus Mortierella alpina for use in infant nutrition was tested in a subchronic (13-week) oral toxicity study in rats, preceded by an in utero exposure phase. The ARA-oil was administered as admixture to the rodent diet at dose levels of 3000 ppm, 15,000 ppm and 75,000 ppm. An additional high-dose group received 75,000 ppm ARA-oil in combination with 55,000 ppm fish oil containing docosahexaenoic acid (DHA), at a ratio of ARA to DHA, comparable to the ratio in mother's milk of 2:1. The total levels of fat in each diet were kept constant by adding the appropriate amounts of corn oil. A concurrent control group received 130,000 ppm corn oil in the diet. An additional carrier control group was fed unsupplemented rodent diet. Administration of the test substances from 4 weeks prior to mating, throughout mating, gestation, lactation of parental (F(0)) animals and weaning of the F(1) pups did not affect fertility or reproductive performance, nor the general condition of pups, viability, sex ratio or number of pups. Pup weight gain in the ARA/DHA-oil group was lower than the controls administered equal amounts of corn oil. In the subsequent subchronic study survival, clinical signs, body weight gain and food consumption were not adversely affected by the test substances. Ophthalmoscopic examination did not reveal any treatment-related changes. There were no treatment-related effects observed up to dietary test substance concentrations of 15,000 ppm. The following statistically significant differences were found in the ARA high-dose group and /or in the ARA/DHA group compared to the corn oil control group: decreased alkaline phosphatase activity, decreases in cholesterol, triglycerides and phospholipids concentrations, increased creatinine and urea concentrations. Furthermore, these groups showed increased adrenal, spleen and liver weights. The incidence of hepatocellular vacuolation was increased in females of the ARA high-dose group and the ARA/DHA group. Oil droplets were observed in the mesenteric lymph nodes and in the intestinal villi in the ARA high-dose group and the ARA/DHA group. In addition, lipogranulomas were observed in the mesenteric lymph nodes in these groups. The observed changes in the high-dose groups may be effects of the high intake of high-fat levels, rather than specific effects of the ARA-oil. The no-observed-effect level in this study was placed at 15,000 ppm ARA-oil. This level is equivalent to approximately 970mg ARA-oil/kg body weight/day.  相似文献   

5.
Endocrine therapy for advanced prostate cancer involves androgen ablation (orchiectomy or application of luteinizing hormone releasing hormone analogs) and/or blockade of the androgen receptor (AR) with either steroidal (cyproterone acetate) or nonsteroidal (hydroxyflutamide, bicalutamide and nilutamide) antiandrogens. These antagonists prevent androgen-induced conformational change and activation of the AR. During long term androgen ablation, the AR adapts to an environment with low androgen concentrations and becomes hypersensitive to low concentrations of androgens, either alone or in combination with various cellular regulators. Bicalutamide can switch from antagonist to agonist during long-term androgen withdrawal, as shown in prostate cancer LNCaP cells. AR point mutations were detected in metastatic lesions from human prostate cancer more frequently than in primary tumors. Although functional characterization of only some mutant AR detected in prostate cancer tissue has been performed, data available suggest that they are activated by dihydrotestosterone, its precursors and metabolites, synthetic androgens, estrogenic and progestagenic steroids and hydroxyflutamide. A direct association between AR mutations and endocrine withdrawal syndrome has been investigated in only one study thus far. There is no evidence at present that activation of any of the mutant AR genes detected in prostate cancer is enhanced in the presence of a nonsteroidal AR stimulator. Coactivators of the AR are proteins that associate with the receptor, possess histone acetylase activity and facilitate AR activation. The coregulatory proteins ARA70 and ARA160 differentially affected the activity of the mutated AR Glu(231)-->Gly, which was discovered in a mouse authochthonous prostate tumor. ARA70 enhanced receptor activation by both androgen and estradiol, whereas ARA160 augmented only androgen-induced AR activity. Novel experimental therapies that down-regulate AR expression have been developed; they include the application of ribozymes and antisense oligonucleotides.  相似文献   

6.
目的 研究视网膜色素上皮细胞(RPE)主要是通过何种亚型的腺苷受体(ARs)来结合腺苷,及其对 RPE 功能的影响。方法 体外培养人 ARPE-19 细胞系,定量 PCR 检测 4 种腺苷受体(ARA1、ARA2A、ARA2B、ARA3)基 因的表达;提取细胞膜蛋白,Western blot 检测 4 种腺苷受体在 RPE 细胞膜上的存在。体外培养 ARPE-19 细胞至 80% 融合后随机分为 A~E 组。其中,A 组为无干预对照组,B~E 组分别给予 ARA1 拮抗剂 DPCPX(50 nmol/L)、 ARA2A 拮抗剂 SCH58261(100 nmol/L)、ARA2B 拮抗剂 MRS1754(100 nmol/L)及 ARA3 拮抗剂 MRS1220(5 μmol/L) 干预。利用 H3-腺苷进行放射性配体结合实验,计算各组细胞对腺苷的最大结合容量(Bmax)。以肿瘤坏死因子 α (TNF-α)10 μg/L 及 γ 干扰素(IFN-γ)1 000 U/mL 联合干预体外培养的 ARPE-19 细胞,给予或不予 ARA1 激动剂 (CCPA),酶联免疫吸附试验(ELISA)测定培养上清中白细胞介素(IL)-6、IL-10、转化生长因子 β(TGF-β)、单核细胞 趋化因子(MCP)-1、趋化因子 C-X-C 配体 10(CXCL10,IP-10)的含量。结果 在 ARPE-19 细胞中即可检测到 4 种 腺苷受体基因的表达,也可探测到其分子在细胞膜上的存在。A~E 组 ARPE-19 细胞结合腺苷的 Bmax (单位:fmol)分 别为 2.04±0.31、0.44±0.06、1.82±0.28、2.01±0.42 及 2.06±0.44,其中 B 组较其他各组 Bmax均降低(P<0.01)。以 TNF- α 及 IFN-γ 激活 ARPE-19 细胞,与对照 RPE 组比较,CCPA 干预 RPE 组 IL-6、MCP-1 及 IP-10 的含量降低、IL-10 的含量增加(P<0.01)。2 组 TGF-β 的含量差异无统计学意义。结论 ARA1 对 ARPE-19 细胞结合腺苷的能力具 有重要的调控作用,ARA1 受体介导的信号可抑制 ARPE-19 细胞分泌促炎因子及驱化因子,具有潜在的免疫抑制 作用。  相似文献   

7.
目的探讨雄激素受体辅助因子(ARA)54在前列腺癌组织中的表达及意义。方法采用免疫组织化学链霉菌抗生物素蛋白-过氧化物酶法(S-P法)检测72例前列腺癌和20例前列腺增生组织中ARA54蛋白的表达。结果 ARA54蛋白在前列腺癌中的阳性表达率显著高于前列腺增生组织。ARA54蛋白的阳性表达与前列腺癌的临床分期呈正相关;与肿瘤分化程度无关。结论前列腺癌组织中存在ARA54蛋白的高表达,ARA54蛋白表达与前列腺癌的临床分期密切相关。  相似文献   

8.
He  Haibo  Li  Xiaomei  Yu  Haili  Zhu  Shu  He  Yumin  Komatsu  Katsuko  Guo  Dongyan  Li  Xiaoqin  Wang  Junzhi  Luo  Huajun  Xu  Daoxiang  Zou  Kun 《Journal of natural medicines》2019,73(2):339-352
Journal of Natural Medicines - The aim of this study was to elucidate the gastroprotective activity and possible mechanism of involvement of araloside A (ARA) against ethanol- and aspirin-induced...  相似文献   

9.
10.
ARA is an adenosine receptor agonist with high affinity for A1 and A2 receptors, which are involved in regulation of free fatty acid (FFA) production. Two parallel groups of 13 healthy males were enrolled in a Phase I study to evaluate the pharmacokinetics of this compound and to characterize its effect on plasma FFA concentrations following administration of a single 6-hour intravenous infusion of ARA or placebo. ARA plasma concentrations were measured by a validated high-performance liquid chromatographic method (fluorescence detection). ARA is a highly cleared compound (Cl: 0.79 L/h/kg) with a modest volume of distribution (Vss: 0.91 L/kg) and short half-life (t1/2: approximately 1 hour). The mean percent change in plasma FFA concentrations relative to placebo was best described by an Emax-based tolerance model, in which a hypothetical metabolite/antagonist was used to describe the apparent development of tolerance to the suppressive effects of ARA on FFA levels. The EC50 values (%RSE of estimate) for ARA and the hypothetical antagonist were 17.0 (5.4) and 15.6 (12.8) ng/mL, respectively. The use of adenosine A1 agonists as antilipolytic drugs may be restricted due to the potential development of tolerance, and thus a period of abstinence from the agonist may be required before the response of FFA returns to pretolerant conditions. In the case of ARA, the value of 0.33 h-1 for Kant0 indicates that a period of approximately 11 hours should suffice. In agreement with preclinical data previously reported in literature, the present study provides evidence that desensitization of adenosine receptor-mediated inhibition of lipolysis may occur in humans. In conclusion, the ability of ARA to reduce circulating levels of FFA can be related to plasma ARA concentrations using a modified Emax-based tolerance model.  相似文献   

11.
目的检测雄激素受体辅助因子(ARA)160在前列腺癌组织和良性前列腺增生标本中的表达情况,分析其与患者的临床病理特征[Gleason评分、临床分期、前列腺特异抗原(PSA)]之间的相关性。方法应用实时定量聚合酶链反应(RT-PCR)(SYBR染料法)技术和免疫组织化学技术,对前列腺癌组织和良性前列腺增生标本中ARA160的表达进行研究。结果良性前列腺增生患者和前列腺癌患者标本中ARA160mRNA均有表达,良性组织中表达量高于前列腺癌组织中的表达,且随着癌组织分期增高ARA160的表达水平降低;Gleason评分≤7分的癌组织比Gleason评分>7分的癌组织表达量高;内分泌治疗有效患者的癌组织比治疗无效患者的癌组织表达量高。结论 ARA160的表达在正常组织中高于癌组织,且与患者的临床特征(Gleason评分、临床分期)显著相关,肿瘤分期越早、Gleason评分≤7分及内分泌治疗有效的患者其ARA160mRNA的表达量越高。ARA160可能是前列腺癌预后的一个良好预测指标,对于指导前列腺癌内分泌治疗有一定的意义。  相似文献   

12.
Erythropoietin (EPO) applies anti-inflammatory, anti-apoptotic, anti-oxidant and cytoprotective effects besides its hematopoietic action. A nonhematopoietic peptide engineered from EPO, ARA 290, interacts selectively with the innate repair receptor and has similar possessions. ARA290 mediates tissue protection without hematopoietic side-effects of EPO which limit its clinical application. Doxorubicin (DOX) is the broad-spectrum chemotherapeutic agent, but its use is limited by the development of nonspecific toxicity on noncancerous tissues especially in cardiac cells. Mechanisms behind the DOX-induced toxicities are enhanced level of oxidative damage, inflammation and apoptosis. In the present study, we have investigated whether ARA290 acts as a chemoprotective agent modulating the cytotoxicity, genotoxicity and oxidative stress induced in vitro by DOX. The genoprotective effect of ARA290 on DOX-induced toxicity in three cell line (HepG2, HGF & Stem cell) were assessed. Cells were treated with ARA290 (50–400 nM) and DOX (1 μM) in pretreatment condition. Cytotoxicity was evaluated using the MTT assay, genoprotective effect of ARA290 were evaluated using the micronucleus test and comet assay. AR290 significantly reduced the percentage of DNA in tail and the frequency of micronuclei induced by DOX. Besides, DOX impaired anti-oxidant defense enzyme activities and induced inflammation and apoptotic cell death. ARA290 markedly attenuated DOX induced oxidative stress and protected against DOX induced inflammation and apoptotic cell death. This result proposes that ARA290 can act as a protective agent, reducing DOX-induced DNA damage and oxidative stress, and it is possible that this protection could also extend to cardiac cells.  相似文献   

13.
目的探讨雄激素受体辅助因子(ARA)70在前列腺癌组织中的表达及意义。方法采用免疫组织化学链霉菌抗生物素蛋白-过氧化物酶连接法(S-P法)检测50例前列腺癌和10例前列腺增生组织中ARA70蛋白的表达。结果 ARA70蛋白在前列腺癌中的阳性表达率(72%)显著高于前列腺增生组织(10%)。ARA70蛋白的阳性表达与前列腺癌的临床分期呈正相关;与肿瘤分化程度无关。结论前列腺癌组织中存在ARA70蛋白的高表达,ARA70蛋白表达与前列腺癌的临床分期密切相关。  相似文献   

14.
Arachidonic acid (ARA) and docosahexaenoic acid (DHA) are routinely added to infant formula to support growth and development. We evaluated the bioequivalence and safety of three ARA-rich oils for potential use in infant formula using the neonatal pig model. The primary outcome for bioequivalence was brain accretion of ARA and DHA. Days 3-22 of age, domestic pigs were fed one of three formulas, each containing ARA at ∼0.64% and DHA at ∼0.34% total fatty acids (FA). Control diet ARA was provided by ARASCO® and all diets had DHA from DHASCO® (Martek Biosciences Corp., Columbia, MD). The experimental diets a1 and a2 provided ARA from Refined Arachidonic acid-rich Oil (RAO; Cargill, Inc., Wuhan, China) and SUNTGA40S (Nissui, Nippon Suisan Kaisha, Ltd., Tokyo, Japan), respectively. Formula intake and growth were similar across all diets, and ARA was bioequivalent across treatments in the brain, retina, heart, liver and day 21 RBC. DHA levels in the brain, retina and heart were unaffected by diet. Liver sections, clinical chemistry, and hematological parameters were normal. We conclude that RAO and SUNTGA40S, when added to formula to supply ∼0.64% ARA are safe and nutritionally bioequivalent to ARASCO in domestic piglets.  相似文献   

15.
Previous studies on the cytotoxicity of arachidonic acid (ARA) elucidated the involvement of oxidative stress and Ca2+. In the present study, the Zn2+-related cytotoxicity of ARA was studied by a flow cytometric technique with appropriate fluorescent probes in rat thymocytes. Addition of 10 μM ZnCl2 enhanced the increase in cell lethality induced by 10 μM ARA. The removal of Zn2+ by Zn2+ chelators attenuated the ARA-induced increase in cell lethality. Thus, Zn2+ is suggested to be involved in ARA cytotoxicity. ARA at 3–10 μM elevated intracellular Zn2+ level. The Zn2+ chelators attenuated the ARA-induced increase in intracellular Zn2+ level while ARA significantly increased intracellular Zn2+ level in the presence of 3 μM ZnCl2, suggesting the involvement of external Zn2+. Zn2+ reportedly exerts cytotoxic action under oxidative stress induced by hydrogen peroxide, via an excessive increase in intracellular Zn2+ levels. Since ARA induces oxidative stress, the simultaneous administration of zinc and ARA may be harmful.  相似文献   

16.
Human milk provides small quantities of preformed docosahexaenoic acid (DHA) and arachidonic acid (ARA), usually less than 1% of total fatty acids. Vegetable oil blends commonly used in infant formulas have, until recently, provided the essential fatty acid precursors for these long-chain polyunsaturated fatty acids (LCPUFA), but no preformed DHA and ARA. This study evaluated the safety of ingredient sources of DHA and ARA for use in infant formulas in a neonatal piglet model. Newborn piglets were allowed to suckle for 3 days and then divided into 4 feeding groups of 6 males and 6 females. Piglets were bottle-fed at frequent feeding intervals until 19 days of age. The composition of the piglet formulas was modeled after standard milk-based formulas for human infants while meeting nutritional requirements for piglets. Formulas were a control formula (no added DHA or ARA), a DHA formula providing 55 mg DHA/100 Cal, an ARA formula providing 96 mg/100 Cal ARA, and a DHA+ARA formula providing 34 mg DHA and 62 mg ARA/100 Cal. All formulas were equal in fat content and provided approximately 1000 Cal/l. The ARA-rich oil was from a fermentation product of Mortierella alpina (40 wt.% fatty acids as ARA) and DHA was from high DHA tuna oil (25 wt.% fatty acids as DHA). There were no test article related effects of DHA and/or ARA indicative of an adverse health consequence to the animals seen in the clinical signs, body weights, food consumption, clinical chemistry, hematology, organ weights or gross or histopathology. The findings in this neonatal animal study support the safety of these ingredient oil sources of DHA and ARA for use in infant formulas.  相似文献   

17.
The polyunsaturated fatty acids (PUFAs), arachidonic acid (ARA) and docosahexaenoic acid (DHA) may play key roles in brain network maturation. ARA plays an important role in signal transduction related to neuronal maturation. This study aims to evaluate the efficacy of supplementing with larger doses of ARA added to DHA in a double-blind, placebo-controlled 16-week trial. To confirm findings observed in the placebo-controlled trial, an additional 16-week open-label study was further conducted. To examine the relationship between the efficacy of the supplementation regimen and alterations in PUFAs levels, we examined plasma levels of PUFAs. We used the Social Responsiveness Scale (SRS) and the Aberrant Behavior Checklist-Community (ABC) to estimate psychotic symptoms. Repeated measures ANOVA revealed that this supplementation significantly improved SRS-measured communication as well as ABC-measured social withdrawal during the placebo-controlled trial. The treatment effect sizes were more favorable for the treatment group compared with the placebo group (communication: 0.87 vs. 0.44; social withdrawal: 0.88 vs. 0.54). At the end of the placebo-controlled trial, there was a significant difference in the change in plasma ARA levels from the baseline and a trend towards a significant difference in plasma ARA levels between the two groups. The open-label study was not powered to detect significant improvements in the outcome measures or significant differences in plasma ARA levels. The present clinical trials suggest that supplementation with larger ARA doses added to DHA improves social impairment in individuals with ASD via ARA-induced upregulation of neuronal functioning.  相似文献   

18.

Aim:

To examine whether two naturally occurring sesquiterpenoids (ST1 and ST2) with anti-proliferative activity in prostate cancer cells inhibit androgen receptor (AR) signaling.

Methods:

Human prostate cancer cell lines LNCaP and PC3 were used. The expression of AR, AR translocation into the nucleus, and expression levels of AR coactivators ARA70 and steroid receptor coactivator-1 (SRC-1) in LNCaP cells were examined using real-time PCR and Western blot. Changes in prostate-specific antigen (PSA) protein levels, PSA promoter activity, and androgen response element (ARE)-mediated reporter gene activity were examined using enzyme-linked immunoabsorbent assay (ELISA) and transient transfection assays. Co-immunoprecipitation was performed to analyze the interaction between AR and the AR coactivators in ST1- and ST2-treated cells.

Results:

In LNCaP cells, ST1 and ST2 (40 μmol/L) led to a significant decrease in the expression of AR as well as a reduction of AR translocation into the nucleus, but had no effect on AR protein translation. ST1 and ST2 treatment also resulted in a significant decrease in the level of PSA protein secreted into the medium and was able to suppress PSA promoter-dependent and ARE-dependent luciferase activity. Furthermore, decreased expression of ARA70 and SRC-1 was observed when LNCaP cells were exposed to ST1 and ST2, which interfered with their ability to interact with AR.

Conclusion:

The observations suggest that suppression of AR transactivation by ST1 and ST2 may be mediated, in part, by inhibiting AR nuclear translocation and/or interfering with the interaction between AR and its coactivators ARA70 and SRC-1. Therefore, sesquiterpenoids could be developed as novel therapeutic agents for treating prostate cancer.  相似文献   

19.
Arachidonic acid (ARA) and docosahexaenoic acid (DHA) are major constituents of cell membranes and play important roles in preserving physiological and psychological function. Recently, data from several studies have indicated that impairments in long-term potentiation (LTP), the process underlying plasticity in synaptic connections, are associated with a decrease in membrane ARA and DHA in aged rats; and treatment of aged rats with either of these polyunsaturated fatty acids (PUFAs) reverses age-related decrease in LTP and the decrease in membrane fatty acid concentration. This review focuses on our recent findings concerning the effects of ARA and DHA on the age-related decline in the function of the brain and cardiovascular system. ARA supplementation decreased P300 latency and increased P300 amplitude of event-related potentials in healthy elderly men. Cognitive impairments in patients with mild cognitive impairment (MCI) and patients with organic brain lesions were significantly improved with ARA and DHA supplementation. ARA and DHA supplementation also increased coronary flow velocity reserve in elderly individuals; this suggests beneficial effects of PUFAs on coronary microcirculation. In conclusion, ARA and DHA may be beneficial in preventing and/or improving age-related declines in brain and cardiovascular system function.  相似文献   

20.
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