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121.
I. Waheed M. Ahmad N-H. Syed Romeeza Ashraf 《Indian journal of pharmaceutical sciences》2014,76(3):251-256
Ballota limbata (Lamiaceae) has been used for its antispasmodic, antiulcer, diuretic, vermifuge and sedative effects in folk medicine. However, little is known about how does it work to produce these therapeutic actions. Present research investigated phytochemical components and antioxidant properties of methanol extract and different fractions of Ballota limbata. In this study, phytochemical investigation was done by performing different chemical tests. Here, antioxidant property of the extract and fractions was investigated by using 1,1-diphenyl-2-picryl hydrazyl radical scavenging activity, total antioxidant activity by the phosphomolybdenum method, linoleic acid peroxidation, ferric thiocyanate analysis and ferric-reducing antioxidant power. Methanol extract and fractions showed presence of numerous chemical principles including alkaloids, cardiac glycosides, tannins and flavonoids. The ethyl acetate fraction exhibited higher scavenging activity compared to the other fractions under investigation. This fraction displayed 84.16±1.02% 1,1-diphenyl-2-picryl hydrazyl radical inhibition at a dose of 60 μg/ml. IC50 for 1,1-diphenyl-2-picryl hydrazylradical-scavenging activity was 13.53±0.22 μg/ml, relative to the standard, butylatedhydroxytoluene, having IC50 of 12.33±0.88 μg/ml. Thus, Ballota limbata showed significant antioxidant activity, which may contribute in the mechanism of above pharmacological actions. 相似文献
122.
《亚太生殖杂志》2014,3(4):263-267
ObjectiveTo investigate whether Vigna unguiculata (V. Unguiculata, VU) able to reduced oxidative stress in cardiac and modulate the aorta estrogen receptor-β of ovariectomized rats.MethodsThirty female Wistar rats were divided into 5 groups (n=6); control (sham) group; ovariectomy group (OVX); OVX + VU1 (0.5 mg/kg); OVX + VU2 (2.5 mg/kg); and OVX + VU3 (5 mg/kg). The administration VU was started 28 days after surgery following 30 days later. Cardiac malondialdehyde (MDA) and superoxide dismutase (SOD) levels were measured colorimetrically. Estrogen receptor-β in the aorta was analyzed immunohistochemically.ResultsLevel of MDA was significantly higher in the OVX group compared to the control group (P< 0.05), but the level of SOD was significantly lower. The level of MDA was significantly lower in OVX + VU compared with OVX group (P<0.05), to reach the level at a control group in OVX + VU2. Administration of VU significantly increases the level of SOD compared with OVX group (P<0.05), to reach the level at a control group in third dose of VU (P>0.05). The level of estrogen receptor-β was significantly decreased in the OVX group compared to the control group (P<0.05). OVX + VU3 could significantly increase the level of estrogen receptor-β compared to OVX group (P<0.05), to reach a level in the control group (P>0.05).ConclusionsV. unguiculata is an alternative therapy in decreasing cardiac oxidative stress in ovariectomized rats. Besides, high dose of V. unguiculata also able to increase aorta estrogen receptor-β expression in ovariectomized rats. 相似文献
123.
Antrodia salmonea is well known in Taiwan as a beneficial mushroom. In the present study, we investigated the antioxidant activity of whole fermented broth (AS), filtrate (ASF), and mycelia (ASM) of A. salmonea using different antioxidant models. Furthermore, the effect of A. salmonea on AAPH-induced oxidative hemolysis of human erythrocytes and CuSO4-induced oxidative modification of human low-density lipoproteins (LDLs) was examined. We found that the AS, ASF, and ASM possess effective antioxidant activity against various oxidative systems including superoxide anion scavenging, reducing power, metal chelation, and DPPH radical scavenging. Further, AAPH-induced oxidative hemolysis in erythrocytes was prevented by AS, ASF, and ASM. Notably, AS, ASF, and ASM appear to possess powerful antioxidant activities against CuSO4-induced oxidative modification of LDL as assessed by malondialdehyde (MDA) formation, cholesterol degradation, and the relative electrophoretic mobility of oxidized LDL. It is noteworthy that AS had comparatively strong antioxidant ability compared to ASF or ASM, which is well correlated with the content of their total polyphenols. Thus, A. salmonea may exert antioxidant properties and offer protection from atherogenesis. 相似文献
124.
Synthesis,Antioxidant, and Xanthine Oxidase Inhibitory Activities of 5‐[4‐[2‐(5‐Ethyl‐2‐pyridinyl)ethoxy]phenyl]methyl]‐2,4‐thiazolidinedione Derivatives
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125.
T. Sindhu S. Rajamanikandan P. Srinivasan 《Indian journal of pharmaceutical sciences》2014,76(2):170-174
The present study was designed to evaluate the antioxidant and antibacterial activity of methanol extract of Kyllinga nemoralis. Six different in vitro antioxidant assays including 2,2-diphenyl-1-picrylhydrazyl, hydroxyl radical, superoxide anion radical, hydrogen peroxide radical, ferric reducing antioxidant power assay and reducing power were carried out to ensure the scavenging effect of the plant on free radicals. In addition, total antioxidant capacity assay, total phenolic contents, tannins, flavonoids and flavonol contents of the plant were also analysed by the standard protocols. Kyllinga nemoralis exhibited high antioxidant activity on 2,2-diphenyl-1-picrylhydrazyl assay (IC50= 90 μg/ml), superoxide radical scavenging assay (IC50= 180 μg/ml) and hydrogen peroxide radical scavenging assay (IC50= 200 μg/ml), compared with standards. These observations provide comprehensible supporting evidence for the antioxidant potential of the plant extract. Reducing power (IC50= 213.16 μg/ml) and hydroxyl radical scavenging activity (IC50= 223 μg/ml) of the plant extract was remarkable. The methanol extract of K. nemoralis exhibited significant antimicrobial activity against Gram-positive human pathogenic bacteria. Standard in vitro antioxidant assays assessed the electron donating ability of the plant extract in scavenging free radicals. The inhibitory effect of the plant extract against bacterial pathogens may be due to the presence of phytochemicals. Thus, the results suggest that Kyllinga nemoralis is a potential source of antioxidants and could serve as the base for drug development. 相似文献
126.
《European journal of pharmaceutics and biopharmaceutics》2014,86(3):418-426
The aim of the present study was to develop and characterize a resveratrol self-emulsifying drug delivery system (Res-SEDDS), and to compare the uptake of resveratrol by bovine aortic endothelial cells (BAECs), and the protection of these cells against hydrogen peroxide-mediated cell death, versus a control resveratrol ethanolic solution.Three Res-SEDDSs were prepared and evaluated. The in vitro self-emulsification properties of these formulations, the droplet size and the zeta potential of the nanoemulsions formed on adding them to water under mild agitation conditions were studied, together with their toxicity on BAECs. An optimal atoxic formulation (20% Miglyol® 812, 70% Montanox® 80, 10% ethanol 96% v/v) was selected and further studied.Pre-incubation of BAECs for 180 min with 25 μM resveratrol in the nanoemulsion obtained from the selected SEDDS significantly increased the membrane and intracellular concentrations of resveratrol (for example, 0.076 ± 0.015 vs. ethanolic solution 0.041 ± 0.016 nmol/mg of protein after 60 min incubation, p < 0.05). Resveratrol intracellular localization was confirmed by fluorescence confocal microscopy. Resveratrol nanoemulsion significantly improved the endothelial cell protection from H2O2-induced injury (750, 1000 and 1500 μM H2O2) in comparison with incubation with the control resveratrol ethanolic solution (for example, 55 ± 6% vs. 38 ± 5% viability after 1500 μM H2O2 challenge, p < 0.05).In conclusion, formulation of resveratrol as a SEDDS significantly improved its cellular uptake and potentiated its antioxidant properties on BAECs. 相似文献
127.
《European journal of pharmaceutics and biopharmaceutics》2014,86(2):251-259
Topical 5% alpha lipoic acid (ALA) has shown efficacy in treatment of photo-damaged skin. The aim of this work was to evaluate the potential of poloxamer (P407) gel as a vehicle for the novel lipid base particulate system (cubosome dispersions) of ALA. Cubosome dispersions were formulated by two different approaches, emulsification of glyceryl monoolein (GMO) and poloxamer (P407) in water followed by ultrasonication, and the dilution method using a hydrotrope. Three different concentrations of GMO were used to formulate the cubosome dispersions using the first method, 5% (D1), 10% (D2) and 15% w/w (D3). In the second technique an isotropic liquid was produced by combining GMO with ethanol, and this isotropic liquid was then diluted with a P407 solution (D4). The dispersions were characterized by zeta potential, light scattering techniques, optical and transmission electron microscopy, encapsulation efficiency and in vitro drug release. Results showed that D4 was not a uniform dispersion and that D1, D2 and D3 were uniform dispersions, in which by increasing the GMO content in the dispersion, the size of the cubosomes decreased, zeta potential became more negative, encapsulation efficiency increased up to 86.48% and the drug release rate was slower. P407 gels were prepared using the cold method. Two concentrations of P407 gel were fabricated, 20 and 30% w/w. P407 gels were loaded with either ALA or dispersions containing ALA cubosomes. P407 gels were characterized by critical gelation temperature, rheological measurements and in vitro drug release studies. Results suggested that by increasing P407 concentration, the gelation temperature decreases and viscosity increases. Drug release in both cases was found to follow the Higuchi square root model. Gel loaded with ALA cubosomes provided a significantly lower release rate than the gel loaded with the un-encapsulated ALA. A double blinded placebo controlled clinical study was conducted, aiming to evaluate the efficacy as an anti-wrinkle agent and volunteer’s satisfaction upon application of topical 30% P407 gel loaded with ALA cubosomes. Results indicated reduction in facial lines, almost complete resolution of fine lines in the periorbital region and upper lip area and overall improvement in skin color and texture in most volunteers. There were no instances of irritation, peeling or other apparent adverse side effects. 相似文献
128.
采用水提醇沉、脱蛋白等工艺制备中药芡实多糖,并通过纤维素柱和葡聚糖凝胶柱分离纯化。精多糖分子量为15 367 Da,其单糖组成为葡萄糖:鼠李糖(0.0142:0.0026),理化反应和红外光谱均符合多糖特征。体外抗氧化实验表明,芡实多糖能够显著清除DPPH、超氧阴离子和过氧化氢等自由基,并具有较强还原力。体内抗氧化实验显示,芡实多糖能够显著提高D-半乳糖所致衰老小鼠的SOD、CAT、GSH—Px水平,降低MDA水平。结果表明,芡实多糖具有广泛的研究前景。 相似文献
129.
目的研究白芍总苷对NAFLD模型大鼠肝脏保护的机制。方法 SD大鼠50只,随机分为正常对照组10只,模型组40只。高脂饲料喂养建模后,模型组随机分为模型对照组、非诺贝特组、白芍总苷高剂量组、白芍总苷低剂量组各10只。连续灌胃给药4周后,测定大鼠血清中ALT、AST、GST、SOD和GSH-PX酶的活性及MDA含量;测定血清中IL-1、TNF-α和TGF-β的水平;各组取肝脏做HE染色,观察肝脏组织学病变。结果与正常对照组比较,NAFLD模型对照组大鼠ALT、AST、GST活性和IL-1、TNF-α、TGF-β含量显著升高,经非诺贝特和白芍总苷干预后,模型组大鼠的ALT、AST、GST活性和IL-1、TNF-α、TGF-β含量均降低回正常水平,差异有统计学意义(P<0.05);与正常对照组比较,NALFD模型大鼠SOD、GSH-PX活性显著降低,MDA含量明显升高,干预治疗后,模型组大鼠SOD、GSH-PX活性大大提高,MDA含量显著降低(P<0.05)。结论白芍总苷对高脂引起的NAFLD模型大鼠有肝脏保护作用,其作用机制可能与其提高抗氧化能力、降低异常细胞因子水平有关。 相似文献
130.
目的:观察川芎嗪对四氯化碳诱导的肝纤维化大鼠肝组织Nrf2/ARE信号通路的影响,探讨川芎嗪治疗肝纤维化的作用机制。方法四氯化碳皮下注射制备大鼠肝纤维化模型,设立正常对照组、肝纤维化模型组和川芎嗪治疗组,川芎嗪治疗组在造模过程中每天给予盐酸川芎嗪注射液腹腔注射,6周后,乙醚麻醉,腹主动脉采血,产色基质偶氮法鲎试剂定量测定血浆内毒素;肝组织常规HE染色观察肝脏病变,天狼猩红胶原染色、肝组织羟脯氨酸含量测定评测肝纤维化程度;West-blotting法检测肝组织内Nrf2蛋白的表达, TBA法检测肝组织丙二醛(MDA)水平,酶显色定量分析法检测肝组织谷胱甘肽-S-转移酶(GST)含量。结果川芎嗪治疗组与肝纤维化模型组相比,肝损伤较轻,肝纤维化程度明显降低,血浆内毒素含量降低, Nrf2蛋白表达量增多,肝组织中MDA含量降低, GST的含量升高。结论川芎嗪的抗肝纤维化作用可能与其降低内毒素血症,激活肝内Nrf2/ARE抗氧化通路进而使得抗氧化酶GST等含量增加有关。 相似文献