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1.
Article in Chinese | WPRIM | ID: wpr-879132

ABSTRACT

The chemical constituents from the extract of the twigs of Euscaphis konishii with anti-hepatoma activity were investigated, twelve compounds by repeated chromatography with silica gel, Sephadex LH-20 and preparative-HPLC. The structures of the chemical components were elucidated by spectroscopy methods, as konilignan(1),(7R, 8S)-dihydrodehydrodico-niferylalcohol-9-O-β-D-glucopyranoside(2),illiciumlignan B(3),threo-1-(4-hydroxy-3-methoxyphenyl)-2-[4-(3-hydroxypropyl)-2-methoxyphenoxy]-1,3-panediol(4),erythro-1-(4-hydroxy-3-methoxyphenyl)-2-[4-(3-hydroxypropyl)-2-methoxyphenoxy]-1,3-panediol(5), matairesinol(6), wikstromol(7), isolariciresinol(8),(+)-lyoniresinol(9), 4-ketopinoresinol(10), syringaresin(11), and vladinol D(12). Among them, compound 1 is a new lignan. Compounds 10 and 12 had moderate inhibitory activity on HepG2 cells, with IC_(50) values of 107.12 μmol·L~(-1) and 183.56 μmol·L~(-1), respectively.


Subject(s)
Chromatography, High Pressure Liquid , Lignans/pharmacology , Plant Extracts/pharmacology
2.
Article in Chinese | WPRIM | ID: wpr-878999

ABSTRACT

Schisandrae has a long history of medicinal use in China. Domestic and foreign scholars have isolated a variety of chemical constituents from Schisandrae Sphenantherae Fructus and Schisandrae Chinensis Fructus, including lignans, volatile oils, polysaccharides, triterpenoids, organic acids, amino acids and so on. Pharmacological studies have shown that their alcohol extracts, water extracts, lignan monomers and polysaccharides could protect liver injury and reduce enzyme ability by a variety of hepatoprotective effects such as enzyme reducing, liver protecting, and antioxidant effect. In this paper, the researches on the chemical composition, hepatoprotective effect and pharmacokinetics of Schisandrae Sphenantherae Fructus and Schisandrae Chinensis Fructus in the past forty years were systematically collated, in order to provide useful enlightenment for the clinical application and new drug development of Schisandrae Sphenantherae Fructus and Schisandrae Chinensis Fructus in liver protection.


Subject(s)
China , Drugs, Chinese Herbal , Fruit , Lignans/pharmacology , Schisandra
3.
Braz. j. med. biol. res ; 52(10): e8385, 2019. graf
Article in English | LILACS | ID: biblio-1039242

ABSTRACT

Malignant melanoma (MM) is one of the malignant tumors with highly metastatic and aggressive biological actions. Schizandrin A (SchA) is a bioactive lignin compound with strong anti-oxidant and anti-aging properties, which is stable at room temperature and is often stored in a cool dry place. Hence, we investigated the effects of SchA on MM cell line A375 and its underlying mechanism. A375 cells were used to construct an in vitro MM cell model. Cell viability, proliferation, apoptosis, and migration were detected by Cell Counting Kit-8, BrdU assay, flow cytometry, and transwell two-chamber assay, respectively. The cell cycle-related protein cyclin D1 and cell apoptotic proteins (Bcl-2, Bax, cleaved-caspase-3, and cleaved-caspase-9) were analyzed by western blot. Alteration of H19 expression was achieved by transfecting with pEX-H19. PI3K/AKT pathway was measured by detecting phosphorylation of PI3K and AKT. SchA significantly decreased cell viability in a dose-dependent manner. Furthermore, SchA inhibited cell proliferation and cyclin D1 expression. SchA increased cell apoptosis along with the up-regulation of pro-apoptotic proteins (cleaved-caspase-3, cleaved-caspase-9, and Bax) and the down-regulation of anti-apoptotic protein (Bcl-2). Besides, SchA decreased migration and down-regulated matrix metalloproteinases (MMP)-2 and MMP-9. SchA down-regulated lncRNA H19. Overexpression of H19 blockaded the inhibitory effects of SchA on A375 cells. SchA decreased the phosphorylation of PI3K and AKT while H19 overexpression promoted the phosphorylation of PI3K and AKT. SchA inhibited A375 cell growth, migration, and the PI3K/AKT pathway through down-regulating H19.


Subject(s)
Humans , Polycyclic Compounds/pharmacology , Down-Regulation/drug effects , Cell Movement/drug effects , Apoptosis/drug effects , Lignans/pharmacology , Cyclooctanes/pharmacology , Cell Proliferation/drug effects , Melanoma/pathology , Signal Transduction/drug effects , Gene Expression Regulation, Neoplastic/drug effects , Blotting, Western , MicroRNAs/metabolism , Cell Line, Tumor , Real-Time Polymerase Chain Reaction , RNA, Long Noncoding
4.
Braz. j. med. biol. res ; 49(7): e5313, 2016. tab, graf
Article in English | LILACS | ID: biblio-951690

ABSTRACT

Ascosphaera apis is a bee pathogen that causes bee larvae infection disease, to which treatment is not yet well investigated. The aim of this study was to investigate antifungal susceptibility in vitro against A. apis and to identify a new antifungal agent for this pathogen through minimal inhibitory concentration (MIC) assay and western blot analysis. Macelignan had 1.56 and 3.125 μg/mL MIC against A. apis after 24 and 48 h, respectively, exhibiting the strongest growth inhibition against A. apis among the tested compounds (corosolic acid, dehydrocostus lactone, loganic acid, tracheloside, fangchinoline and emodin-8-O-β-D-glucopyranoside). Furthermore, macelignan showed a narrow-ranged spectrum against various fungal strains without any mammalian cell cytotoxicity. In spite of miconazole having powerful broad-ranged anti-fungal activity including A. apis, it demonstrated strong cytotoxicity. Therefore, even if macelignan alone was effective as an antifungal agent to treat A. apis, combined treatment with miconazole was more useful to overcome toxicity, drug resistance occurrence and cost effectiveness. Finally, HOG1 was revealed as a target molecule of macelignan in the anti-A. apis activity by inhibiting phosphorylation using S. cerevisiae as a model system. Based on our results, macelignan, a food-grade antimicrobial compound, would be an effective antifungal agent against A. apis infection in bees.


Subject(s)
Animals , Ascomycota/drug effects , Bees/microbiology , Lignans/pharmacology , Mitogen-Activated Protein Kinases/drug effects , Saccharomyces cerevisiae Proteins/drug effects , Antifungal Agents/pharmacology , Tetrazolium Salts , Time Factors , Microbial Sensitivity Tests , Blotting, Western , Mitogen-Activated Protein Kinases/analysis , Saccharomyces cerevisiae Proteins/analysis , Drug Synergism , Formazans , Larva/drug effects , Larva/microbiology , Larva/pathogenicity , Mycoses/drug therapy
5.
Bol. latinoam. Caribe plantas med. aromát ; 14(3): 171-178, mayo 2015. ilus, tab
Article in English | LILACS | ID: biblio-907482

ABSTRACT

Compounds such as triclosan, diclofenac and trimetropin posses antibacterial activity, including mycobacterial; their structures are based on two aromatic rings joined by a methylene or a heteroatom. Since a similar structural system is found in natural diarylfuran- based lignans, we studied plants known with this type of lignans, as potential active against Mycobacterium tuberculosis. Fractions of the active extracts were tested for anti-TB activity and their chemical constituents analyzed by NMR spectroscopy. Several extracts and chromatographical fractions exhibited > 90 percent inhibition of M. tuberculosis at 128 ug/mL. Methylpluviatilol, a pure compound isolated from Virola sebifera, was active at this concentration.. These findings suggest that plant species of the families here studied may yield novel lead compounds for the development of antimycobacterial agents.


Compuestos tales como triclosan, diclofenac y trimetoprim poseen actividad antibacterial, incluyendo la antimicobacterial; sus estructuras están basadas en dos anillos aromáticos unidos por un metileno o un heteroátomo. Debido a que en la naturaleza se encuentra un sistema estructural similar del tipo diarilfurano en los lignanos, así como otros subtipos, nosotros estudiamos plantas contra Mycobacterium tuberculosis, de las que se sabe contienen lignanos Las fracciones cromatográficas de los extractos activos fueron ensayadas para actividad anti.Tb y sus constituyentes químicos se analizaron por espectroscopía de RMN. Varios extractos y fracciones cromatográficas exhibieron una inhibición superior al 90 por ciento a 128 ug/mL; el compuesto metilpluviatilol, aislado de mostró una inhibición del 99 por ciento a esa concentración. Esos hechos sugieren que las especies de plantas de las familias aquí estudiadas podrían suministrar nuevos compuestos líderes para el desarrollo de agentes antimicobacteriales.


Subject(s)
Anti-Bacterial Agents/pharmacology , Furans/pharmacology , Lignans/pharmacology , Mycobacterium tuberculosis , Biological Assay , Magnetic Resonance Spectroscopy
6.
Rev. bras. plantas med ; 17(4,supl.1): 782-789, 2015. tab, graf
Article in Portuguese | LILACS | ID: lil-770369

ABSTRACT

RESUMO: A atividade antimicobacteriana de diidrocubebina (1), uma lignana dibenzilbutanodioica obtida a partir de extrato etanólico de sementes da Piper cubeba, e seus derivados foram avaliados in vitro contra três diferentes cepas de Mycobacterium utilizando o método de microdiluição. Dentre as lignanas avaliadas 3 e 4 foram as mais ativas, exibindo valores de CIM de 62,5 µg/mL contra M. avium e M. tuberculosis, respectivamente. Os derivados 2-6 obtidos por síntese parcial possuem diferentes substituintes nos carbonos 9 e 9 ', que alteram polaridade, solubilidade e limitam as rotações livres entre C8-C8' em relação de material (1) de partida. As diferenças estruturais entre estes compostos podem fornecer informações importantes sobre a relação estrutura-atividade antimicobacteriana do esqueleto dibenzilbutanodioico, obtido a partir de fonte natural, como um possível alvo para o desenvolvimento de drogas mais potentes contra a tuberculose


ABSTRACT: Evaluation of antimycobacterial activity of dihydrocubebin lignan extracted from Piper cubeba and its semisynthetic derivatives. The antimycobacterial activity of the dihydrocubebin (1), a dibenzylbutanedioiclignan obtained from ethanolic extract of Piper cubeba seeds, and its derivatives were examined in vitro against three different strains of Mycobacterium using amicrodilution method. Among the lignans evaluated, the 3 and 4 samples were the most active ones, displaying MIC values of 62.5 µg/mL against M. avium and M. tuberculosis, respectively. The derivatives 2-6, obtained for partial synthesis, had different substituents in the carbons 9 and 9', fact thatalters the polarity, solubility and restricts the free rotations between the bonds C8-C8' in relation to the starting material (1). The structural differences among these compounds provide important information about the antimycobacterial structure-activity relationship of the dibenzylbutanodioic skeleton, obtained from natural source, such as a possible target for the development of more powerful drugs against tuberculosis


Subject(s)
Anti-Bacterial Agents/pharmacology , Lignans/pharmacology , Piper/classification , In Vitro Techniques/instrumentation , Mycobacterium avium/classification , Mycobacterium tuberculosis/classification
7.
Indian J Cancer ; 2012 Jan-Mar; 49(1): 181-187
Article in English | IMSEAR | ID: sea-144569

ABSTRACT

Background: Actin cytoskeleton is involved in actin-based cell adhesion, cell motility, and matrix metalloproteinases(MMPs) MMP2, MMP9, MMP11 and MMP14 are responsible for cell invasion in breast cancer metastasis. The dietary intake of lignan from flax seed gets converted to enterolactone (EL) and enterodiol in the human system. Here we show that the enterolactone has a very significant anti-metastatic activity as demonstrated by its ability to inhibit adhesion and invasion and migration in MCF-7 and MDA MB231 cell lines. Materials and Methods: Migration inhibition assay, actin-based cell motility assay along with reverse transcriptase polymerase chain reaction (RT-PCR) for MMP2, MMP9, MMP11 and MMP14 genes were performed in MCF-7 and MDA MB 231 cell lines. Results: Enterolactone seems to inhibit actin-based cell motility as evidenced by confocal imaging and photo documentation of cell migration assay. The results are supported by the observation that the enterolactone in vitro significantly down-regulates the metastasis-related metalloproteinases MMP2, MMP9 and MMP14 gene expressions. No significant alteration in the MMP11 gene expression was found. Conclusions: Therefore we suggest that the anti-metastatic activity of EL is attributed to its ability to inhibit cell adhesion, cell invasion and cell motility. EL affects normal filopodia and lamellipodia structures, polymerization of actin filaments at their leading edges and thereby inhibits actin-based cell adhesion and cell motility. The process involves multiple force-generating mechanisms of actin filaments i.e. protrusion, traction, deadhesion and tail-retraction. By down-regulating the metastasis-related MMP2, MMP9 and MMP14 gene expressions, EL may be responsible for cell invasion step of metastasis.


Subject(s)
4-Butyrolactone/analogs & derivatives , 4-Butyrolactone/pharmacology , Actin Cytoskeleton/drug effects , Breast Neoplasms/diet therapy , Breast Neoplasms/pathology , Cell Adhesion/drug effects , Cell Movement/drug effects , Female , Flax/metabolism , Gene Expression Regulation, Neoplastic/drug effects , Humans , Lignans/administration & dosage , Lignans/metabolism , Lignans/pharmacology , MCF-7 Cells , Matrix Metalloproteinases/genetics , Matrix Metalloproteinases/metabolism , Neoplasm Invasiveness , Neoplasm Metastasis
8.
Article in English | WPRIM | ID: wpr-194084

ABSTRACT

Nitric oxide (NO) produced by endothelial NO synthase (eNOS) plays an important role in vascular functions, including vasorelaxation. We here investigated the pharmacological effect of the natural product syringaresinol on vascular relaxation and eNOS-mediated NO production as well as its underlying biochemical mechanism in endothelial cells. Treatment of aortic rings from wild type, but not eNOS-/- mice, with syringaresinol induced endothelium-dependent relaxation, which was abolished by addition of the NOS inhibitor NG-monomethyl-L-arginine. Treatment of human endothelial cells and mouse aortic rings with syringaresinol increased NO production, which was correlated with eNOS phosphorylation via the activation of Akt and AMP kinase (AMPK) as well as elevation of intracellular Ca2+ levels. A phospholipase C (PLC) inhibitor blocked the increases in intracellular Ca2+ levels, AMPK-dependent eNOS phosphorylation, and NO production, but not Akt activation, in syringaresinol-treated endothelial cells. Syringaresinol-induced AMPK activation was inhibited by co-treatment with PLC inhibitor, Ca2+ chelator, calmodulin antagonist, and CaMKKbeta siRNA. This compound also increased eNOS dimerization, which was inhibited by a PLC inhibitor and a Ca2+-chelator. The chemicals that inhibit eNOS phosphorylation and dimerization attenuated vasorelaxation and cGMP production. These results suggest that syringaresinol induces vasorelaxation by enhancing NO production in endothelial cells via two distinct mechanisms, phosphatidylinositol 3-kinase/Akt- and PLC/Ca2+/CaMKKbeta-dependent eNOS phosphorylation and Ca2+-dependent eNOS dimerization.


Subject(s)
Animals , Aorta/drug effects , Enzyme Activation/drug effects , Furans/pharmacology , Gene Deletion , Human Umbilical Vein Endothelial Cells/drug effects , Humans , Lignans/pharmacology , Mice , Mice, Inbred C57BL , Nitric Oxide/metabolism , Nitric Oxide Synthase Type III/genetics , Phosphatidylinositol 3-Kinases/metabolism , Phosphoinositide Phospholipase C/metabolism , Phosphorylation/drug effects , Protein Multimerization/drug effects , Proto-Oncogene Proteins c-akt/metabolism , Vasodilation/drug effects
9.
Rio de Janeiro; s.n; 2011. 54 p. tab, graf.
Thesis in Portuguese | LILACS | ID: lil-617851

ABSTRACT

Avaliamos o efeito do consumo materno de SDG (Diglicosídeo Secoisolariciresinol) e de óleo de Linhaça+SDG sobre parâmetros bioquímicos e hormonais das ratas e das proles machos e fêmeas na lactação. As ratas lactantes foram separadas em: controle (C), ração controle cuja proteína foi caseína; (SDG): ração C com 400mg de SDG/Kg de ração; OLSDG: ração C com 400mg de SDG/Kg de ração e 7% de óleo de linhaça. No 14º e 20º dias de lactação as ratas foram ordenadas e no 21º dia foram sacrificadas por punção cardíaca. Leite e soro foram coletados para avaliação bioquímica e hormonal. Hormônios foram quantificados por radioimunoensaio. As proles machos e fêmeas foram sacrificadas aos 14 e 21 dias de idade. Os animais foram eviscerados para análise da composição corporal. Monitoramos a ingestão alimentar e a massa corporal (MC) durante o período experimental. As ratas SDG apresentaram maior gordura corporal (GC; +39%), enquanto as OLSDG menor conteúdo mineral (-20%) e trigliceridemia (TG) (-39%). As ratas SDG e OLSDG apresetaram hiperprolactinemia (+389% e 153%, respectivamente) sem alteração na concentração de estradiol. No 14º dia de lactação, o leite das ratas OLSDG apresentou menores teores de lactose (-17%) e de proteínas (-20%) e o das ratas SDG apenas menor teor de proteína (-21%). A partir do 13º dia de lactação tanto os machos quanto as fêmeas OLSDG apresentaram menor MC (-14%, -16%, respectivamente). No 14º dia de lactação os machos SDG e OLSDG apresentaram menor gordura corporal (-24%, -55%, respectivamente) e a prole SDG maior massa de gordura visceral (+39%). Os machos SDG apresentaram maiores concentrações de TG (+105%) e hipoprolactinemia (-41%). Os machos OLSDG também apresentaram hipoprolactinemia (-41%). As fêmeas SDG e OLSDG apresentaram maior estradiol aos 14 dias (+86% e +176%) que se normalizou aos 21 dias, maior colesterolemia (+16%) e as SDG apresentaram maior trigliceridemia (+74%). Aos 21 dias os machos e as fêmeas SDG e OLSDG...


We evaluated the mother's intake of SDG (Diglicoside secoisolariciresinol) and flaxseed oil + SDG upon biochemical and hormonal parameters of lactating female rats and the male and female offspring during lactation. The female lactating rats were divided into: Control (C): feeding a diet with casein; (SDG): feeding diet C added 400mg of SDG/Kg diet; (OLSDG): diet C added 400mg of SDG/Kg diet and 7% of flaxseed oil. Milk samples were obtained on the 14th and 20th days of lactation and the mothers were sacrificed and blood collected by cardiac puncture on the 21st day. Milk and serum were collected for biochemical and hormonal analysis. The male and female offsprings were sacrified on the 14th and 21th day. The hormonal dosages were measured by radioimunassay. The animals were completely eviscerated to analyze body composition. Body mass (BM) and food intake were monitored during all experimental period. The SDG rats showed higher fat mass (+39%) while the OLSDG rats showed lower mineral content (-20%) and triglycerides (TG) serum levels (-39%). The SDG and OLSDG rats showed higher prolactin levels (+339% and +153% respectively) without changes in serum estradiol. On the 14th day of lactation we observed lower lactose (-17%) and protein (-20%) content in the OLSDG rat's milk while in the SDG only lower protein (-21%). From the 13th day of lactation both the males and females OLSDG showed lower BM (-14%, -16%, respectively). On the 14th day the male SDG and OLSDG showed lower fat mass (-24%, -55%, respectively), and the SDG offspring showed higher visceral fat mass (+39%). The SDG male also showed higher TG levels (+105%) and lower prolactin levels (-41%). The OLSDG males also showed lower prolactin serum levels (-41%). The OLSDG female showed higher serum estradiol at 14 days (+86% e +176%), which normalized at 21 days and higher cholesterolemia (+16%) and the SDG female presented higher TG levels (+74%). On day 21th day the male and female SDG and OLSDG...


Subject(s)
Animals , Infant , Rats , Body Composition , Food Composition , Maternal Nutritional Physiological Phenomena , Infant Nutritional Physiological Phenomena , Glucosides/metabolism , Hyperprolactinemia/etiology , Lactation/physiology , Lignans/pharmacology , Linseed Oil/pharmacokinetics , Linseed Oil/metabolism
10.
Article in English | WPRIM | ID: wpr-171914

ABSTRACT

Our previous report has demonstrated that 5-formylhonokiol (FH), a derivative of honokiol (HK), exerts more potent anti-proliferative activities than honokiol in several tumor cell lines. In present study, we first explored the antiangiogenic activities of 5-formylhonokiol on proliferation, migration and tube formation of human umbilical vein endothelial cells (HUVECs) for the first time in vitro. Then we investigated the in vivo antiangiogenic effect of 5-formylhonokiol on zebrafish angiogenesis model. In order to clarify the underlying molecular mechanism of 5-formylhonokiol, we investigated the signaling pathway involved in controlling the angiogenesis process by western blotting assay. Wound-healing results showed that 5-formylhonokiol significantly and dose-dependently inhibited migration of cultured human umbilical vein enthothelial cells. The invasiveness of HUVEC cells was also effectively suppressed at a low concentration of 5-formylhonokiol in the transwell assay. Further F-actin imaging revealed that inhibitory effect of 5-formylhonokiol on invasion may partly contribute to the disruption of assembling stress fiber. Tube formation assay, which is associated with endothelial cells migration, further confirmed the anti-angiogenesis effect of 5-formylhonokiol. In in vivo zebrafish angiogenesis model, we found that 5-formylhonokiol dose-dependently inhibited angiogenesis. Furthermore, western blotting showed that 5-formylhonokiol significantly down-regulated extracellular signal-regulated kinase (ERK) expression and inhibited the phosphorylation of ERK but not affecting the total protein kinase B (Akt) expression and related phosphorylation, suggesting that 5-formylhonokiol might exert anti-angiogenesis capacity via down-regulation of the ERK signal pathway. Taken together, these data suggested that 5-formylhonokiol might be a viable drug candidate in antiangiogenesis and anticancer therapies.


Subject(s)
Actins/metabolism , Angiogenesis Inhibitors/pharmacology , Animals , Antineoplastic Agents, Phytogenic/pharmacology , Biphenyl Compounds/pharmacology , Blotting, Western , Cell Line, Tumor , Cell Movement/drug effects , Cell Proliferation/drug effects , Cells, Cultured , Dose-Response Relationship, Drug , Drugs, Chinese Herbal , Embryo, Nonmammalian/drug effects , Endothelium, Vascular/drug effects , Extracellular Signal-Regulated MAP Kinases/antagonists & inhibitors , Humans , Lignans/pharmacology , Neovascularization, Physiologic/drug effects , Signal Transduction/drug effects , Umbilical Veins/cytology , Wound Healing , Zebrafish/embryology
11.
Mem. Inst. Oswaldo Cruz ; 105(1): 45-51, Feb. 2010. tab, ilus
Article in English | LILACS | ID: lil-539295

ABSTRACT

Tuberculosis (TB - Mycobacterium tuberculosis) is an ancient infectious disease that has appeared once again as a serious worldwide health problem and now comprises the second leading cause of death resulting from a single infection. The prevalence of multidrug resistance (MDR) TB is increasing and therapeutic options for treatment are not always accessible; in fact, some patients do not respond to the available drugs. Therefore, there is an urgent need to develop novel anti-TB agents. The aim of the present study was to screen extracts of Aristolochia taliscana, a plant used in traditional Mexican medicine to treat cough and snake bites, for antimycobacterial activity. The hexanic extract of A. taliscana was tested by microdilution alamar blue assay against Mycobacterium strains and bioguided fractionation led to the isolation of the neolignans licarin A, licarin B and eupomatenoid-7, all of which had antimycobacterial activity. Licarin A was the most active compound, with minimum inhibitory concentrations of 3.12-12.5 ìg/mL against the following M. tuberculosis strains: H37Rv, four mono-resistant H37Rv variants and 12 clinical MDR isolates, as well as against five non-tuberculous mycobacteria (NTM) strains. In conclusion, licarin A represents a potentially active anti-TB agent to treat MDR M. tuberculosis and NTM strains.


Subject(s)
Humans , Anti-Bacterial Agents/pharmacology , Aristolochia/chemistry , Lignans/pharmacology , Mycobacterium tuberculosis/drug effects , Plant Extracts/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/isolation & purification , Drug Resistance, Multiple, Bacterial , Lignans/isolation & purification , Mexico , Microbial Sensitivity Tests , Mycobacterium/classification , Mycobacterium/drug effects , Plant Extracts/chemistry
12.
Biol. Res ; 42(3): 351-356, 2009. ilus, tab
Article in English | LILACS | ID: lil-531968

ABSTRACT

Schisandra propinqua (Wall.) Baill.(Schisandraceae) is widely used as a Chinese folk medicine. In this study, activity-guided fractionation of the ethanol extract from the stem of Schisandra propinqua led to the isolation of four extracts. Subsequently, a neolignan 4,4-di(4-hydroxy-3-methoxyphenly)-2,3-dimethylbutanol was isolated from the EtOAc part of the stem of Schisandra propinqua, the free radical scavenging activities of which were researched in vitro. The present work demonstrated that extracts and pure compound possessed scavenging activities to DPPH, superoxide anions and hydroxy radical, and could depress lipid peroxidation reaction induced by oxygen radical produced by the Fe2+/cysteine system in vitro. This suggests that the traditional application of Schisandra propinqua in China may be related to its antioxidant activities, and the EtOAc part of the stems of Schisandra propinqua can be utilized as an effective source of antioxidants.


Subject(s)
Animals , Male , Rats , Antioxidants/pharmacology , Lignans/pharmacology , Lipid Peroxidation/drug effects , Plant Extracts/pharmacology , Schisandra/chemistry , Antioxidants/chemistry , Antioxidants/isolation & purification , Biphenyl Compounds , Hydroxyl Radical/analysis , Lignans/chemistry , Lignans/isolation & purification , Picrates , Peroxides/analysis , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Rats, Wistar , Superoxides/analysis
13.
Article in English | IMSEAR | ID: sea-118688

ABSTRACT

The incidence of and mortality from prostatic cancer in the West is higher than that in Asian countries. Migrants from Asia to western countries, who maintain their traditional diet, do not have an increased risk of prostatic cancer. This has been attributed in part to 'phyto-oestrogens' in vegetarian Asian diets. Prostatic cancer is a hormone-dependent disease and oestrogens retard the growth of prostatic tumours by interfering with the action of testosterone. Oestrogen increases the level of sex hormone-binding globulin that binds testosterone, resulting in lower free testosterone levels, thereby decreasing androgenic stimulation of the prostate. Oestrogens used to retard the growth of prostatic cancer are associated with certain undesirable side-effects. Phyto-oestrogens have weak oestrogenic potency and anticancer effects. Thus, these phytochemicals have a possible role in the prevention of hormone-dependent diseases such as prostatic cancer. Although the relative potencies of various phyto-oestrogens compared with oestradiol are low, the oestrogen receptor (ER) complexes formed byoestradiol and isoflavones have functional similarities. Also, phyto-oestrogens have a higher affinity to bind to ER-beta than ER-alpha. They are antiproliferative and inhibit tyrosine and other protein kinases which play a key role in tumorigenesis, and also inhibit the production of the potent androgen 5alpha dihydrotestosterone in the prostate. Since prostatic cancer cells usually multiply slowly and the development of this cancer can take many years before symptoms appear, the latent period provides a chemopreventive opportunity for natural therapy with phyto-oestrogens. Although phyto-oestrogens have not yet been used in long-term trials to evaluate their ability to reduce the risk of prostate carcinoma, the evidence thus far suggests that they have a protective effect against the growth of prostate tumours.


Subject(s)
Asian Continental Ancestry Group , Chemoprevention , Diet, Vegetarian , Emigration and Immigration , Humans , Isoflavones/pharmacology , Lignans/pharmacology , Male , Phytoestrogens , Plant Preparations/pharmacology , Prostatic Neoplasms/diet therapy , Testosterone/antagonists & inhibitors
14.
Rev. chil. pediatr ; 70(2): 92-9, mar.-abr. 1999. ilus, tab
Article in Spanish | LILACS | ID: lil-244021

ABSTRACT

Los fitoestrógenos son sustancias ambientales naturales, producidas por plantas, que a pesar de su estructura química distinta de los estrógenos, actúan como tales. Estudios en adultos sugieren que tendrían efectos protectores para cánceres hormonodependientes (de próstata y mama), dislipidemias y de la mineralización ósea. Se clasifican en isoflavonas, cumestanos y lignanos, y se encuentran principalmente en legumbres y poroto de soya, brotes de poroto, forraje y granos, y en cereales de grano entero y semillas, respectivamente. Estudios recientes han demostrado que los alimentos infantiles, incluyendo algunas fórmulas lácteas, yogur y alimentos de soya, contienen cantidades considerables de fitoestrógenos. Los efectos de estos sobre la salud infantil no han sido del todo aclarados. Existen evidencias epidemiológicas y clínicas de que al actuar como estrógenos débiles prodrían determinar adelanto de los eventos puberales y telarquia en la niña y ginecomastia en el varón. Se hace una revisión del tema y se plantea la necesidad de realizar estudios destinados a aclarar los efectos de los estrógenos ambientales sobre la salud infantil


Subject(s)
Humans , Child , Coumestrol/pharmacology , Growth Substances/pharmacology , Herbal Medicine , Lignans/pharmacology , Coumestrol/adverse effects , Coumestrol/metabolism , Growth Substances/classification , Isoflavones/adverse effects , Isoflavones/metabolism , Lignans/adverse effects , Lignans/metabolism , Infant Nutrition , Puberty, Precocious/etiology
15.
Braz. j. med. biol. res ; 30(5): 599-604, May 1997. tab
Article in English | LILACS | ID: lil-196670

ABSTRACT

Aluminum (Al3+) intoxication is thought to play a major role in the development of Alzheimer's disease and in certain pathologic manifestations arising from long-term hemodialysis. Although the metal does not present redox capacity, it can stimulate tissue lipid peroxidation in animal models. Furthermore, in vitro studies have revealed that the fluoroaluminate complex induces diacyglycerol formation, 43-kDa protein phosphorylation and aggregation. Based on these observations, we postulated that Al3+-induced blood platelet aggregation was mediated by lipid peroxidation. Using chemiluminescence (CL) of luminol as an index of total lipid peroxidation capacity, we established a correlation between lipid peroxidation capacity and platelet aggregation. Al3+ (20-100 muM) stimulated CL production by human blood platelets as well as their aggregation. Incubation of the platelets with the antioxidants nor-dihydroguaiaretic acid (NDGA) (100 muM) and n-propyl gallate (NPG) (100 muM), inhibitors of the lipoxygenase pathway, completely prevented CL and platelet aggregation. Acetyl salicylic acid (ASA) (100 muM), an inhibitor of the cyclooxygenase pathway, was a weaker inhibitor of both events. These findings suggest that Al3+ stimulates lipid peroxidation and the lipoxygenase pathway in human blood platelets thereby causing their aggregation.


Subject(s)
Humans , Adult , Aluminum/pharmacology , L-Lactate Dehydrogenase/analysis , Lignans/pharmacology , Lipid Peroxidation/drug effects , Platelet Aggregation/drug effects , Propyl Gallate/pharmacology , Ristocetin/pharmacology , Salicylates/pharmacology , Aluminum/analysis , Luminescent Measurements
16.
CCS ; 12(1): 14-6, jan. 1990-jun. 1993. tab, graf
Article in Portuguese | LILACS | ID: lil-168424

ABSTRACT

Neste estudo, os autores relatam os dados da avaliaçao dos efeitos a nível do sistema nervoso central da iangambina, uma lignana furofurânica isolada da Ocotea duckei Vattimo. Os principais efeitos observados em camundongos, foram: potencializaçao do tempo de sono induzido por pentobarbital e bloqueio das convulsoes induzidas por pentilenotetrazol.


Subject(s)
Animals , Male , Mice , Central Nervous System Depressants/pharmacology , Central Nervous System/drug effects , Lignans/pharmacology , Lignans/toxicity , Pentobarbital/pharmacology , Pentylenetetrazole/pharmacology , Seizures , Sleep/drug effects
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