Ethanol extract of Graptopetalum paraguayense upregulates paraoxonase 1 gene expression via an AKT/NF-κB-dependent pathway

Human serum paraoxonase 1 (PON1), a calcium-dependent ester hydrolase, protects against the oxidative modification of low-density lipoprotein (LDL) and is a major anti-atherosclerotic component of high-density lipoprotein (HDL). Graptopetalum paraguayense, a folk herbal medicine commonly used in Taiwan, has antioxidative, anti-inflammatory, anti-hypertensive, and anti-atherogenic properties. The effects of G. paraguayense on the activity and/or expression of PON1 were examined using various extracts of the plant; extracts were made in water (GPWE), 50% ethanol (GP50E), and 95% ethanol (GP95E). Of these extracts, GP50E was found to be the most effective at increasing the function and expression of PON1 in a human hepatoma HepG2 cell line. Data from electrophoretic mobility shift assays and promoter-reporter luciferase analyses demonstrated that the DNA binding activity and transactivation ability of NF-κB were enhanced by GP50E. Treatment with NF-κB inhibitors, pyrrolidine dithiocarbamate, and BAY 11-7082 significantly attenuated GP50E-induced PON1 production and NF-κB transactivation activity. In addition, GP50E increased the levels of phosphorylated protein kinase B (PKB/AKT). Pharmacological inhibition of AKT by LY294002 effectively suppressed NF-κB activation and PON1 gene expression, suggesting that AKT was an upstream regulator of GP50E-mediated biological events. Overall, the results show that GP50E up-regulated PON1 gene expression via an AKT/NF-κB-dependent signaling pathway in human hepatoma HepG2 cells. This observation led to the conclusion that the anti-atherogenic characteristics of G. paraguayense are modulated, at least in part, via the up-regulation of hepatocyte PON1 gene expression.     

Free radical scavenging activity of Elsholtzia densa

Medicinal plants have been used traditionally to cure a variety of diseases since ancient times. Elsholtzia densa, a rare annual herb of the Kashmir valley, was assessed for its antioxidant efficacy. Antioxidant activity of the crude extracts was evaluated using 1, 1- diphenyl-2-picryl hydrazyl free radical (DPPH), DNA sugar damage, lipid peroxidation, ferric thiocyanate (FTC) and hydrogen peroxide scavenging assays. The maximum percentage decrease of 1,1-diphenyl-2-picryl hydrazyl radical (DPPH) standard solution was recorded for the 50% ethanolic extract (90.48%). The extracts were further evaluated using the thiobarbituric acid reactive substances assay. The methanolic extract showed the highest activity (32.02%) in reducing oxidative damage to DNA. The antioxidant activity of the extracts was also determined using the linoleic acid system and the highest antioxidant activity (49.64%) was found in the 50% ethanolic extract. In the case of the FTC assay, the 50% ethanolic extract showed the highest activity (70.14%) which was comparable to that of α-tocopherol. Moreover, total phenolics concentration was found to be 62.5mg% and 77.5mg% in the cases of absolute ethanolic and 50% ethanolic extracts, respectively. These findings indicate promising antioxidant activity of crude extracts of the plant and the need for further exploration of their effective use in both modern and traditional systems of medicine.     

Antioxidant properties of Glossogyne tenuifolia

Glossogyne tenuifolia (Labill) Cass. (Compositae) is a special medicinal plant in the Pescadores Islands. Ethanolic, cold and hot water extracts were prepared from the dried herb and their antioxidant properties and components were studied. Ascorbic acid, alpha-tocopherol, butylated hydroxyanisole, citric and ethylenediaminetetraacetic acids were used in assays for comparison. With regard to EC(50) values in antioxidant activity, ethanolic and hot water extracts (0.08 and 0.09 mg/ml) were much more effective than the cold water extract (0.76 mg/ml). At 1.0 mg/ml, reducing capacities were 1.57, 0.31 and 1.04 for ethanolic, cold water and hot water extracts, respectively. Scavenging abilities on 1,1-diphenyl-2-picrylhydrazyl radicals were in descending order: ethanolic > cold water > hot water extracts. At 20 mg/ml, the hot water extract chelated all hydroxyl ions (100%) whereas the scavenging ability of the cold water extract was 68.86%. Chelating abilities on ferrous ions were in descending order: cold water > hot water > ethanolic extracts. Phenols were found to be the major antioxidant components. All EC(50) values were below 20 mg/ml, and some even below 0.1 mg/ml, indicating that all three extracts from G. tenuifolia were rich in antioxidant properties.     

In vitro antioxidant and antimicrobial activity of extracts from Morus alba L. leaves, stems and fruits

In this study, the aqueous and ethanolic extracts (leaves, stems and fruits) from Morus alba L., a traditional Chinese medicine, were evaluated for their antioxidant and antimicrobial properties. Ethanolic extracts showed higher contents of both total phenolics and flavonoids than aqueous extracts. The total phenolic content was in the order of: leaf extracts > fruit extracts > stem extracts, whereas the total flavonoids was: leaf extracts > stem extracts > fruit extracts. Using DPPH assays, the concentrations providing 50% inhibition (IC(50)) values of aqueous extracts from leaves, stems and fruits were 7.11 ± 1.45 mg/ml, 86.78 ± 3.21 mg/ml and 14.38 ± 2.83 mg/ml, respectively, whereas the IC(50) values of ethanolic extracts were 3.11 ± 0.86 mg/ml, 14.62 ± 2.45 mg/ml and 12.42 ± 2.76 mg/ml, respectively. In sum, the antioxidant activities of ethanolic extracts from M. alba L. were stronger than the aqueous extracts, and in the order of: leaf extracts > fruit extracts > stem extracts. The ethanolic extracts exhibited moderate antimicrobial activities, whereas the aqueous extracts showed poor antimicrobial properties in our test system. This study validated the medicinal potential of M. alba L.     

Antioxidant activity of Siamese neem tree (VP1209)

Leaves, fruits, flowers and stem bark extracts from the Siamese neem tree (Azadirachta indica A. Juss var. siamensis Valeton, Meliaceae) were assessed for antioxidant activity in vitro using the 1,1-diphenyl-2-picryl hydrazyl (DPPH) scavenging assay, total antioxidant activity and inhibition of lipid peroxidation in Chago K1 cancer cell culture by the thiobarbituric acid reactive substances (TBARS) method. The results showed that leaf aqueous extract, flower and stem bark ethanol extracts exhibited higher free radical scavenging effect on the DPPH assay with 50% scavenging activity at 26.5, 27.9 and 30.6 microg/ml, respectively. The total antioxidant activity of these extracts was found to be 0.959, 0.988 and 1.064 mM of standard trolox, respectively. At 100 microg/ml, the flower ethanol and leaf aqueous extracts significantly decreased malondialdehyde (MDA) levels (46.0 and 50.6%, respectively) by the TBARS method. The results suggest that extracts from leaf, flower and stem bark of the Siamese neem tree have strong antioxidant potential. This report supports the ethnomedical use of young leaves and flowers of this plant as a vegetable bitter tonic to promote good health.     

Chemical composition analysis, antioxidant, antiglycating activities and neuroprotective effects of S. choloroleuca, S. mirzayanii and S. santolinifolia from Iran

This study was designed to examine antioxidant activities, antiglycating abilities and neuroprotective effects of methanolic extracts of Salvia choloroleuca, Salvia santolinifolia and Salvia mirzayanii from Iran. The extracts were screened for their possible antioxidant activities by several biochemical assays such as DPPH, FRAP, β-carotene bleaching and TEAC assays. HPLC analysis of these extracts led to the separation of a number of components such as catechine and rosmarinic acid. Based on our results, all these plants had antioxidant and antiglycating activities, among them S. choloroleuca seems to be the most effective one. Furthermore, these species not only showed no cytotoxic effects in neuron-like PC12 cells, but also protected them against oxidative stress-induced cell death, exerted by H(2)O(2). We further showed that these plants increase superoxide dismutase and catalase levels, reduce lipid peroxidation and up regulate hemeoxygenase-1 and glutamylcysteine synthetase proteins. This study raised the possibility of developing these plants as potential neuroprotective agents.     

黄芩脂质过氧化抑制率与有效成分含量的相关性研究

目的：对黄芩脂质过氧化抑制率与有效成分含量的相关性进行研究。方法：建立鼠肝微粒体脂质过氧化模型，以硫代巴比妥酸法评估黄芩及其主要成分黄芩素、黄芩苷和汉黄芩素不同比例组合样品在此模型中的抗脂质过氧化活性。结果：抗脂质过氧化活性以黄芩素最强，依次为黄芩苷和汉黄芩素。黄芩药材的IC₅₀在2.72～18.27 mg·L^-1。结论；黄芩的抗脂质过氧化活性除与有效成分的浓度有关外，还与其组成的比例密切相关。     

Screening of antioxidant activity of three Indian medicinal plants,traditionally used for the management of neurodegenerative diseases

A number of Indian medicinal plants have been used for thousands of years in the traditional system of medicine (Ayurveda). Amongst these are plants used for the management of neurodegenerative diseases such as Parkinson's, Alzheimer's, loss of memory, degeneration of nerves and other neuronal disorders by the Ayurvedic practitioners. Though the etiology of neurodegenerative diseases remains enigmatic, there is evidence, which indicates that defective energy metabolism, excitotoxicity and oxidative damage may be crucial factors (Ann. Neurol. 38 (3) (1995) 357). The part of the Ayurvedic system that provides an approach to prevention and treatment of degenerative diseases is known as Rasayana, and plants used for this purpose are classed as rejuvenators. This group of plants generally possesses strong antioxidant activity (Pharmacol. Biochem. Behav. 43 (1992) 1175), but only a few have been investigated in detail. In the present study, three such rasayana plants were tested for the first time for their toxicity and free radical scavenging activity both in vitro and ex vivo. All the three plant infusions (up to 1 mg/ml) showed no toxic effects on the viability of PC12 cell line as judged by MTT-test. Both ethanolic extracts and water infusions of the plants were tested for their antioxidant activity in the 2,2'-azinobis-3-ethyl-benzothiazoline-6-sulfonic acid (ABTS*(+)) radical cation decolorization assay; inhibition of lipid peroxidation by plant infusions was carried out using spontaneous lipid peroxidation of rat brain homogenate, and IC50 values were determined. The results from the ABTS assay showed that the ethanolic extract of Sida cordifolia was found to be most potent (IC50 16.07 microg/ml), followed by Evolvulus alsinoides (IC50 33.39 microg/ml) and Cynodon dactylon (IC50 78.62 microg/ml). The relative antioxidant capacity for the water infusions was observed in the following order: E. alsinoides (IC50 172.25 microg/ml)>C. dactylon (IC50 273.64 microg/ml)>S. cordifolia (IC50 342.82 microg/ml). The results of water infusions of the plants on lipid peroxidation were as follows: E. alsinoides (IC50 89.23 microg/ml)>S. cordifolia) (IC50 126.78 microg/ml)>C. dactylon (IC50 608.31 microg/ml).     

Antioxidant activity of Crataegus aronia aqueous extract used in traditional Arab medicine in Israel

BACKGROUND: The medicinal use of extracts prepared from plant parts of the genus Crataegus dates back to ancient times. Furthermore, it has been proposed that its antioxidant constituents account for its beneficial therapeutic effects. A decoction of leaves and unripe fruits from Crataegus aronia syn. azarolus (L) (Rosaceae), the indigenous Israeli hawthorn, is used to treat cardiovascular diseases, cancer, diabetes and sexual weakness in Arab traditional medicine. PURPOSE: Because laboratory data on the bioactivity of extracts prepared from the indigenous Israeli hawthorn is lacking, we evaluated the antioxidant and cytotoxic potentials of an extract prepared from leaves and unripe fruits in a variety of cell and cell-free in vitro assays. METHODS: The antioxidant assays measured: (a) its ability to inhibit (i) oxidation of beta-carotene, (ii) 2,2'-azobis(2-amidino-propan) dihydrochloride (AAPH)-induced plasma oxidation and (iii) iron-induced lipid peroxidation in rat liver homogenates; (b) its ability to scavenge the superoxide (O2-) radical; (c) its effects on the enzyme xanthine oxidase (XO) activity; (d) its effect on the redox state of glutathione (GSH) in cultured Hep G2 cells. In addition, we also evaluated the effects of the extract on cell membrane integrity and mitochondrial respiration in cultured Hep G2 cells. RESULTS AND CONCLUSIONS: Water-soluble extracts inhibited (1) oxidation of beta-carotene, (2) AAPH-induced plasma oxidation and (3) Fe(2+)-induced lipid peroxidation in rat liver homogenates. In addition, the extract (4) is an efficient scavenger of the O2- (5) increases intracellular GSH levels and (6) is not cytotoxic. Accordingly, we propose that the therapeutic benefit of Crataegus aronia can be, at least in part, attributed to its effective inhibition of oxidative processes, efficient scavenging of O2- and possible increasing GSH biosynthesis.     

Antioxidant activities of some common ingredients of traditional chinese medicine, Angelica sinensis, Lycium barbarum and Poria cocos

The antioxidant activities of three popular ingredients of traditional Chinese medicine, namely Angelica sinensis (AS), Lycium barbarum (LB) and Poria cocos (PC) were evaluated in this study. The results showed that aqueous extracts of these crude drugs exhibited antioxidant activities in a concentration-dependent manner. All extracts displayed an inhibitory effect on FeCl2-ascorbic acid induced lipid peroxidation in rat liver homogenate in vitro, with the order of activity LB > AS > PC. The tested extracts showed a superoxide anion scavenging activity ranging from 28.8% to 82.2% and anti-superoxide activity varying from 38.0% to 84.5%. Among the different extracts, LB extract exhibited the lowest IC50 values (0.77-2.55 microg/mL) in all model systems tested in this study. The present study concludes that LB extract possessed the strongest inhibition on malondialdehyde formation in rat liver homogenate, and superoxide anion scavenging and anti-superoxide formation activities. These results also suggest that LB extract is a good source of antioxidant agent in the daily dietary supplement.     

Evaluation of antioxidant potential of the cultured mycobiont of a lichen Usnea ghattensis

The biologically active compounds, antioxidant activities and free radical scavenging effects of dry matter of cultural medium (DMCM), filtrate (DMF) and different solvent extracts of mycobiont from lichen species Usnea ghattensis in submerged culture (UGSC) were investigated. DMF showed the strongest inhibition of lipid peroxidation as a function of its concentration, and was comparable to the antioxidant activity of BHA at the same concentration of 0.2 mg/mL. The hexane extract of mycobiont had the weakest antioxidant ability, whereas other mycobiont extracts exhibited a modest to strong inhibition of lipid peroxidation and in free radical scavenging activity. The antioxidant activities of mycobiont extracts were correlated with the presence of total polyphenol content in the extract. It was found that antioxidant components in methanol, acetone, ethanol and hexane extracts must be derived from the secondary metabolites produced by the lichen mycobiont. The results presented herein indicate that extracts of cultured mycobiont of lichen Usnea ghattensis could possibly act as chemopreventing agent with respect to free radical-related diseases.     

Antioxidant and cytotoxic activities of Retama raetam subsp. Gussonei

The aim of this study was to evaluate the in vitro antioxidant and cytotoxic activities of the methanol extracts of Retama raetam subsp. gussonei leaves and seeds. The antioxidant activity of the extracts was assessed by means of two different tests: (1) bleaching of the stable 2,2-diphenyl-1-picrylhydrazil (DPPH) radical; and (2) lipid peroxidation of liposomes which were prepared from bovine brain extract. In both tests used leaves extract showed a significant antioxidant effect. The extract of leaves also demonstrated a good cytotoxic activity against COR-L23 (large cell carcinoma) cell line.     

Hepatoprotective and antioxidant activities of Tetracera loureiri

Tetracera loureiri is one of the most valued herbs in Thai traditional medicine. In this study, we describe its in vitro and in vivo antioxidant and hepatoprotective activities. The ethanol extract of T. loureiri possessed potent antioxidant and strong free radical scavenging properties assayed using ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH), respectively. The cytoprotective effects of T. loureiri were demonstrated in ethanolic extracts of freshly isolated rat hepatocytes against the chemical toxicants paracetamol and tertiary-butylhydroperoxide. The cells pretreated with the extract maintained the GSH/GSSG ratio and suppressed lipid peroxidation in a dose dependent manner. Pretreating rats with the ethanol extract orally, one hour prior to intraperitoneal injection of toxic doses of paracetamol, significantly prevented elevations of plasma ALT and AST. These results suggest that T. loureiri may be of potential therapeutic value in some liver disorders.     

Antiproliferative and apoptotic effects of tetrandrine on different human hepatoma cell lines

Tetrandrine (TET), a bis-benzylisoquinoline alkaloid isolated from the dried root of Hang-Fang-Chi (Stephania tetrandra S. Moore), is well known to possess activities including antioxidant, anti-inflammation, anti-fibrotic and anticancer. It is used clinically to treat hypertension and silicosis. In the present study, the anti-proliferative and apoptotic effects of TET were evaluated on three different hepatoma cell lines, namely Hep G2, PLC/PRF/5 and Hep 3B. Using XTT assay, results showed that the IC50 values of TET were 4.35 microM for Hep G2, 9.44 microM for PLC/PRF/5 and 10.41 microM for Hep 3B cells. The CC50 of TET against BNL-CL.2 mouse normal liver cells was 31.12 microM. Interestingly, TET exhibited a lower IC50 value and better selectivity against Hep G2 and PLC/PRF/5 cells than cisplatin. Microscopic observation study, DNA fragmentation assay and flow cytometric analysis further supported apoptotic effect of TET on both PLC/PRF/5 and Hep 3B cells. The cell cycle of PLC/PRF/5 treated with TET appeared to arrest at G2/M phase in a dose-dependent manner, whereas no effect was noted on the cell cycle of Hep 3B cells. The present study concludes that TET exhibited anti-proliferative effect on Hep G2, PLC/PRF/5 and Hep 3B cells in a dose-dependent manner. TET also possesses a lower IC50 and better SI value than cisplatin against Hep G2 and PLC/PRF/5 cells. The effect of TET on cell cycle progression was found to vary with the type of hepatoma cells, suggesting the genetic make-up of the cells play an important role in the response to drug treatment.     

Screening and comparison of antioxidant activity of solvent extracts of herbal medicines used in Korea

The hexane, ethylacetate, n-butanol, and water extracts of 10 Korean herbal medicines were screened and compared for their antioxidant activities in a range of lipid peroxidation system using rat brain homogenates, antihemolysis assay of red blood cells, and other in vitro assays to determine their ability to scavenge superoxide and hydroxyl radicals. All of the 10 Korean herbal medicines have potent antioxidant activities. Among the four solvent extracts, the antioxidant activities of more-polar solvent extracts (BuOH and water extracts) were relatively higher than that of non-polar solvent extracts (hexane and EtOAC extracts). These results will be useful to further analyze those herbal medicines that contain the most antioxidant activity in order to identify the active principles.     

Further studies on the hepatoprotective effects of Cochlospermum tinctorium rhizomes.

The hepatoprotective activity of the rhisome of Cochlospermum tinctorium was investigated using carbon tetrachloride toxicity on mouse and tert-butyl hydroperoxide in vitro induction of lipid peroxidation and hepatocyte lysis. Aqueous, hydro-ethanolic and ethanolic extracts showed significant dose-dependent hepatoprotective actions. The ethanolic extract showed a hepatoprotective activity at lower doses than silymarin. The ethanolic and hydro-ethanolic extracts exhibited remarkable effects against the induction of lipid peroxidation and hepatocyte lysis; the aqueous extract showed comparatively weaker effects. These differences were related to the chemical composition of the extracts. Among the identified constituents of the drug, phenolic and polyphenolic compounds (gallic and ellagic acids, ellagitannins, flavonoids), carotenoids, triterpenes could be related to the biological activity.     

Antioxidant activity of the extracts from fruiting bodies of cultured Cordyceps sinensis

Cordyceps sinensis is one of the most valued herbs in traditional Chinese medicine. We investigated the antioxidant activities of the cultured fruiting bodies of Cordyceps sinesis. The water and ethanol extracts of Cordyceps sinensis were found to possess a potent antioxidant activity. The scavenging effects of the extracts on superoxide were very weak, but the extracts moderately inhibited malondialdehyde formation via hydroxyl radical induced by SIN-1, a peroxynitrite generator. Of the extracts examined, the hot water extract (70 degrees C for 5 min) showed the greatest oxygen free radical scavenging activity. Also, when low-density lipoprotein (LDL) was incubated with macrophages in the presence of CuCl2 (1 microM), the hot water extract showed a strong inhibitory effect against lipid peroxidation in the medium and consequent accumulation of cholesteryl ester in macrophages. Their activities were comparable to that of authentic Cu/Zn SOD. These results suggest that the extracts of cultured Cordyceps sinensis possess potent antioxidant and anti-lipid peroxidation activities and inhibit accumulation of cholesteryl ester in macrophages via suppression of LDL oxidation.     

Antioxidant properties of Ballota species growing in Turkey

In the present study, the antioxidant properties of ethanol extracts of 16 Ballota species belonging to the Lamiaceae family and growing in Turkey on superoxide anion formation and lipid peroxidation were investigated. All extracts inhibited superoxide anion formation but to different extents. The extracts of Ballota antalyense, Ballota macrodonta, Ballota glandulosissima, Ballota larendana, Ballota pseudodictamnus, Ballota nigra subsp. anatolica, Ballota saxatilis subsp. saxatilis, Ballota rotundifolia, and Ballota saxatilis subsp. brachyodonta exhibited remarkable anti-superoxide anion formation with IC(50) values from 0.50 to 0.87 mg/ml. The extracts of Ballota antalyense, Ballota macrodonta and Ballota glandulosissima have the lowest IC(50) values (0.50, 0.51 and 0.51 mg/ml, respectively) which were rather close to the well-known superoxide anion scavenger alpha-tocopherol (IC(50): 0.22 mg/ml). The extracts of Ballota inaequidens, Ballota glandulosissima, Ballota saxatilis subsp. saxatilis, Ballota macrodonta and Ballota antalyense inhibited lipid peroxidation with IC(50) values from 12 to 20 mg/ml. The extracts of Ballota inaequidens (IC(50): 12 mg/ml) and Ballota glandulosissima (IC(50): 15 mg/ml) exhibited the strongest inhibitory effects on lipid peroxidation compared with alpha-tocopherol (IC(50): 3 mg/ml). The results show that Ballota glandulosissima is the best antioxidant source among these 16 Ballota species.     

Antioxidant and antiglycation properties of total saponins extracted from traditional Chinese medicine used to treat diabetes mellitus

Eleven antidiabetic traditional Chinese medicine (TCM) extracts rich in saponins were examined for their antioxidant and antiglycation activities. The antioxidant activities of these extracts were evaluated by studying the inhibition of lipid peroxidation in rat liver microsomes induced by ascorbate/Fe2+, cumine hydroperoxide (CHP) or CCl4/reduced form of nicotinamide-adenine dinucleotide phosphate (NADPH). The antioxidant capacities were also evaluated by studying the scavenging of 2,2'-diphenyl-1-picrylhydrazyl (DPPH) free radical. The antiglycation activities of these extracts were evaluated by hemoglobin-delta-gluconolactone (delta-Glu) assay, bovine serum albumin (BSA)-glucose assay and N-acetyl-glycyl-lysine methyl ester (GK peptide)-ribose assay. Aralia taibaiensis outperformed other extracts in most of the assays except inhibition of early glycation products formation, where Acanthopanax senticosus showed higher activity. Aralia taibaiensis was particularly potent in inhibiting the late glycation and formation of advanced glycation end products (AGEs) on proteins. The antioxidant and antiglycation activities of most extracts were correlated with the saponin content. The results demonstrate that the antidiabetic activities of most extracts could be explained, at least in part, by their combined antioxidant and antiglycation properties.     

六味地黄生物制剂抗衰老活性部位的筛选研究

目的:筛选六味地黄生物制剂抗衰老的活性部位。方法:经口喂饲果蝇0.1%六味地黄生物制剂不同部位提取物(乙酸乙酯提取物,正丁醇提取物,水提物)和0.1%六味地黄生物制剂,并以普通培养基作为空白对照,通过果蝇寿命实验,繁殖力实验,以及测量给药30天果蝇体内谷胱甘肽过氧化物酶(GSH-PX),总抗氧化物(TAOC),超氧化物歧化酶(SOD),过氧化氢酶(CAT)活性及丙二醛(MDA)含量。结果:寿命实验中,正丁醇提取物能延长果蝇平均和最高寿命;酶实验中,正丁醇提取物能不同程度地提高GSH-PX,TAOC,SOD,CAT活力,降低MDA水平;繁殖力实验中,正丁醇提取物能明显增加果蝇子代成虫数量。结论:正丁醇提取物具有良好的抗衰老的作用。