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At least 19 recordsLinked to original sources

PubMed2002

Antioxidants from the bark of Burkea africana, an African medicinal plant.

The bark of the tree Burkea africana is used medicinally in large areas of sub-Saharan Africa. The constituents responsible for its putative activity are not well known. We have investigated the bark of B. africana for antioxidant and radical scavenging activity. A hydroethanol bark extract showed high activity, and most of this activity was located in semipolar fractions of the extract. From chromatographic purification and spectroscopical structure studies, we conclude that the active constituents are proanthocyanidins. Two major components appear to be fisetinidol-(4alpha- --> 8)-catechin 3-gallate and bis-fisetinidol-(4alpha- --> 6, 4alpha- --> 8)-catechin 3-gallate. The latter compound is a new natural product. Smaller amounts of monomeric flavan-3-ols (catechin, epicatechin and fisetinidol) were also found.

Animals↗

PubMed2006

Allergy-preventive phenolic glycosides from Populus sieboldii.

Allergy-preventive activity was demonstrated for an extract of the bark of Populus sieboldii in a continuing search for allergy-preventive substances from natural sources. By bioassay-directed fractionation of this plant bark, two new phenolic glycosides, siebolside A {2-hydroxy-5-[(benzoyloxy)methyl]phenyl (6'-O-acetyl) beta-D-glucopyranoside} (1) and siebolside B {2-hydroxy-5-[(benzoyloxy)methyl]phenyl beta-D-glucopyranoside} (2), were isolated, together with three known compounds, salicin (3), sakuranin (4), and neosakuranin (5). The structures of 1 and 2 were elucidated by spectroscopic methods. Compounds 1-5 all showed allergy-preventive effects.

Animals↗

PubMed2001

Additional evidence for the anti-inflammatory and anti-allergic properties of the sesquiterpene polygodial.

This study evaluates further the anti-inflammatory and anti-allergic properties of polygodial, a sesquiterpene extracted from the barks plant Drymis winteri (Winteraceae). Polygodial (12.8-128.1 micromol/kg, i.p.) 30 min prior, inhibited significantly the mouse paw oedema induced by prostaglandin E2, bradykinin (BK) substance P (SP), dextran, platelet activating factor (PAF) or carrageenan. Polygodial also inhibited arachidonic acid-, capsaicin- and croton oil-induced ear oedema in mice. Polygodial (42.7 micromol/kg, i.p.), significantly inhibited both exudation and cell influx when assessed in the pleurisy induced by SP and histamine, and to a less extent the inflammatory response caused by carrageenan, PAF, BK and des-Arg9-BK. Finally, polygodial (4.2-42.7 micromol/kg, i.p.) produced dose-related inhibition of paw oedema induced by ovalbumin, protecting in a time-dependent manner the anaphylactic shock induced by endovenous administration of ovalbumin in animals which had been actively sensitised by this antigen. These and our previous results indicate that the major component present in the bark of the plant D. winteri, the sesquiterpene polygodial exerts an interesting anti-inflammatory and anti-allergic properties when assessed in rats and mice.

Anaphylaxis↗

PubMed2000

Analgesic and antiinflammatory activities of an extract from Parkia biglobosa used in traditional medicine in the Ivory Coast.

In the Ivory coast, Parkia biglobosa (Mimosaceae) is used in traditional medicine as an analgesic drug, especially against dental pain. Of the three extracts obtained from the plant bark, the hexane fraction was studied to determine its analgesic and/or antiinflammatory activities. The results show that this extract possesses a marked analgesic activity when evaluated with the abdominal writhing test in mice, but, like paracetamol, was ineffective with the hot-plate method, a feature suggesting a peripheral mechanism of action. This activity was accompanied by an antiinflammatory effect, somewhat weaker than the analgesic one.

Analgesics↗

PubMed2002

Pygeum africanum for benign prostatic hyperplasia.

BACKGROUND: Benign prostatic hyperplasia (BPH), nonmalignant enlargement of the prostate, can lead to obstructive and irritative lower urinary tract symptoms (LUTS). The pharmacologic use of plants and herbs (phytotherapy) for the treatment of LUTS associated with BPH has been growing steadily. The extract of the African prune tree, Pygeum africanum, is one of the several phytotherapeutic agents available for the treatment of BPH. OBJECTIVES: To investigate the evidence whether extracts of Pygeum africanum (1) are more effective than placebo in the treatment of Benign Prostatic Hyperplasia (BPH), (2) are as effective as standard pharmacologic BPH treatments, and (3) have less side effects compared to standard BPH drugs. SEARCH STRATEGY: Trials were searched in computerized general and specialized databases (MEDLINE (1966-2000), EMBASE, Cochrane Library, Phytodok), by checking bibliographies, and by contacting relevant manufacturers and researchers. SELECTION CRITERIA: Trials were eligible if they (1) were randomized (2) included men with BPH (3) compared preparations of Pygeum africanum (alone or in combination) with placebo or other BPH medications (4) included clinical outcomes such as urologic symptom scales, symptoms, or urodynamic measurements. Eligibility was assessed by at least two independent observers. DATA COLLECTION AND ANALYSIS: Information on patients, interventions, and outcomes were extracted by at least two independent reviewers using a standard form. The main outcome measure for comparing the effectiveness of Pygeum africanum with placebo and standard BPH medications was the change in urologic symptoms scale scores. Secondary outcomes included change in urologic symptoms including nocturia and urodynamic measures (peak and mean urine flow, prostate size). The main outcome measure for adverse effects was the number of men reporting adverse effects. MAIN RESULTS: A total of 18 randomized controlled trials involving 1562 men met inclusion criteria and were analyzed. Only one of the studies reported a method of treatment allocation concealment, though 17 were double-blinded. There were no studies comparing Pygeum africanum to standard pharmacologic interventions such as alpha-adrenergic blockers or 5-alpha reductase inhibitors. The mean study duration was 64 days (range, 30-122 days). Many studies did not report results in a method that permitted meta-analysis. Compared to men receiving placebo, Pygeum africanum provided a moderately large improvement in the combined outcome of urologic symptoms and flow measures as assessed by an effect size defined by the difference of the mean change for each outcome divided by the pooled standard deviation for each outcome (-0.8 SD [95% confidence interval (CI), -1.4, -0.3 (n=6 studies)]). Men using Pygeum africanum were more than twice as likely to report an improvement in overall symptoms (RR=2.1, 95% CI = 1.4, 3.1). Nocturia was reduced by 19%, residual urine volume by 24% and peak urine flow was increased by 23%. Adverse effects due to Pygeum Africanum were mild and comparable to placebo. The overall dropout rate was 12% and was similar between Pygeum Africanum (13%), placebo (11%) and other controls (8%). REVIEWER'S CONCLUSIONS: A standardized preparation of Pygeum africanum may be a useful treatment option for men with lower urinary symptoms consistent with benign prostatic hyperplasia. However, the reviewed studies were small in size, were of short duration, used varied doses and preparations and rarely reported outcomes using standardized validated measures of efficacy. Additional placebo-controlled trials are needed as well as studies that compare Pygeum africanum to active controls that have been convincingly demonstrated to have beneficial effects on lower urinary tract symptoms related to BPH. These trials should be of sufficient size and duration to detect important differences in clinically relevant endpoints and use standardized urologic symptom scale scores.

Humans↗

PubMed2005

Phytochemical evaluation of selected antioxidant-containing medicinal plants for use in the preparation of a herbal formula--a preliminary study.

Oxidative damage is implicated in the pathogenesis of a number of diseases. Scientific research shows positive links between accumulated free-radical damage and age-related diseases such as atherosclerosis, Alzheimer, and osteoarthritis. There are reports that plant-derived phenolic compounds such as flavonoids have antioxidant properties capable of reducing the risk of developing these diseases. This work aims to evaluate the antioxidant activity of selected medicinal plants traditionally used by herbalists, in particular for the treatment of arthritis, with a view to developing a formula for treating age and age-related diseases. Thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC) analyses of each plant confirmed the presence of a number of flavonoids reported in the literature, as well as unidentified compounds. The antioxidant activities of these plants were determined by DPPH (= '1,1-diphenyl-2-picryl-hydrazyl') radical scavenging, and by inhibition of linoleic acid peroxidation. All the crude plant extracts showed marked antioxidant activities in both assays. The extracts' inhibitory effects on linoleic acid peroxidation was concentration-dependent, with the highest activity shown at 0.1% (w/v). These results suggest that the phenolic compounds, particularly the flavonoids, may, in part, be responsible for the antioxidant activity of traditional plant extracts.

Antioxidants↗

PubMed2006

Cinnamon water extracts increase glucose uptake but inhibit adiponectin secretion in 3T3-L1 adipose cells.

The effects of three concentrations (0.2, 0.3, and 0.4 mg/mL) of a cinnamon extract (CE) (Cinnamomum zeylanicum) on glucose uptake and adiponectin secretion in 3T3-L1 adipocytes were examined in the presence and absence of 0.5 nM and 50 nM insulin. In the absence of insulin, adipocytes exposed to 0.2 mg/mL CE showed an approximate two-fold increase in glucose uptake relative to controls although glucose uptake was unaffected by the two higher concentrations of CE. No effect of CE on glucose uptake was noted in the presence of 0.5 nM insulin whereas the two highest concentrations (0.3 and 0.4 mg/mL) of CE showed a significant dose-dependent decrease in glucose uptake in the presence of 50 nM insulin. Treatment of the adipocytes with 50 nM wortmannin, an irreversible inhibitor of the p110 isoform of phosphoinositide 3'-kinase, was associated with complete inhibition of the stimulated glucose uptake induced by 0.2 mg/mL CE. Treatment of the adipocytes with 0.2 mg/mL CE was associated with an inhibition of adiponectin secretion to levels that were nondetectable. The present study indicates that although 0.2 mg/mL CE has insulin-mimetic action in 3T3-adipocytes in terms of glucose uptake, secretion of the antidiabetic hormone adiponectin is adversely affected.

3T3-L1 Cells↗

PubMedDate not supplied

Quantitative determination for cytotoxic Friedo-nor-oleanane derivatives from five morphological types of Maytenus ilicifolia (Celastraceae) by reverse-phase high-performance liquid chromatography.

Five different morphological types of Maytenus ilicifolia of the same age and harvested under the same conditions showed distinct accumulations of some friedo-nor-oleananes. A rapid, sensitive and reliable reverse-phase HPLC method (employing an external standard) was used for the determination of the cytotoxic triterpenoids, 20 alpha-hydroxymaytenin, 22 beta-hydroxymaytenin, maytenin, celastrol and pristimerin in each of the five types. Well resolved peaks with good detection response and linearity in the range 1.0-100 micrograms/mL were obtained.

Antineoplastic Agents, Phytogenic↗

PubMedDate not supplied

The structural elucidation of a novel iridoid derivative from Tachiadenus longiflorus (Gentianaceae) using the LSD programme and quantum chemical computations.

Oleanolic acid, scoparone, scopoletin and a novel iridoid derivative, angelone, were isolated from Tachiadenus longiflorus (Gentianaceae). The structure of angelone was determined from NMR data, given as input to the Logic for Structure Determination Programme, and was finally confirmed by comparison of experimental 13C-NMR chemical shifts with those obtained by quantum mechanical calculations.

Gentianaceae↗

PubMed2006

Regeneration of the secondary vascular system in poplar as a novel system to investigate gene expression by a proteomic approach.

Wood formation is a complex process composing many biological events. To access its key developmental stages, we have established a regeneration system that can mimic the initiation and differentiation of cambium cells for Chinese white poplar. Anatomical studies showed that new cambium and xylem re-appeared in sequence within a few weeks after being debarked. This provides the opportunity to follow key stages of wood formation by sampling clonal trees at different regeneration times. We used this system in combination with a proteomic approach to analyze proteins expressed in different regeneration stages. PMFs for 244 proteins differentially displayed were obtained and queried against public databases. Putative functions of 199 of these proteins were assigned and classified. Regulatory genes for cell cycle progression, differentiation and cell fate were expressed in the formation of cambial tissue, while 27 genes involved in secondary wall formation were predominantly found in the xylem developing stage. This indicates that the change of gene expression pattern is corresponding to the progression of second vascular system regeneration when and where the key events of wood development occur. Further exploration of these interesting genes may provide insight into the molecular mechanisms of wood formation.

Electrophoresis, Gel, Two-Dimensional↗

PubMed2002

Antioxidant properties of Indian medicinal plants.

The antioxidant properties of methanol extracts of 12 Indian medicinal plants, traditionally used in disease areas that probably involve free radical mechanisms, were evaluated by two methods, namely the DPPH (1,1-diphenyl-2-picryl hydrazyl) test and the lipid peroxidation assay. In the latter assay, seven of these extracts showed 90% or more activity compared with the standard, vitamin E and hence were studied in detail after the removal of interfering pigments. The selective pigment removal from the extracts led to an increase in free radical scavenging activity and a decrease in inhibition of lipid peroxidation.

Animals↗

PubMed2003

Acaricidal activity of Uvaria versicolor and Uvaria Klaineana (Annonaceae).

Three Uvaria species, namely U. klaineana, U. mocoli and U. versicolor were tested in vitro against Dermatophagoides pteronyssinus, the European house dust mite. The most active extracts were the Uvaria versicolor stems crude methanol and hexane extracts with EC(50) values of 0.095 g/m(2 )and 0.12 g/m(2), respectively. The bioassay-guided fractionation of the hexane extract led to the isolation of benzyl benzoate (1). which exhibited an EC(50) value of 0.045 g/m(2). A new fl avanone, versuvanone (2). and the known oxoaporphine liriodenine (3). were also isolated from this species and showed EC(50) values > 1.5 g/m(2). A weak acaricidal activity (0.85 g/m(2)) was observed for the dichloromethane extract of Uvaria klaineana, due to the presence of benzyl benzoate. Uvaria mocoli was inactive. The structures of compounds were elucidated using 2D-NMR techniques.

Dermatophagoides pteronyssinus↗

PubMed2003

Butanolides from Machilus thunbergii and their inhibitory activity on nitric oxide synthesis in activated macrophages.

In activated macrophages the inducible form of nitric oxide synthase (iNOS) generates high amounts of the toxic mediator, nitric oxide (NO), that contributes to the circulatory failure associated with septic shock. Three butanolides were isolated from Machilus thunbergii as active principles which inhibit the production of NO in lipopolysaccharide-activated RAW 264.7 cells, and their structures were identified as litsenolide A2 (1), B1 (2) and B2 (3). They showed dose-dependent inhibition of NO syntheses and the IC(50)s were 3.36, 3.70 and 6.19 micro m, respectively. These new inhibitors of iNOS may have potential in the treatment of endotoxaemia and inflammation accompanied by the overproduction of NO.

Cell Line↗

PubMed2003

Mangifera indica L. extract (Vimang) and mangiferin modulate mouse humoral immune responses.

The present study investigated the effects of orally administered Vimang (an aqueous extract of Mangifera indica) and mangiferin (the major polyphenol present in Vimang) on mouse antibody responses induced by inoculation with spores of microsporidian parasites. Inoculation induced specific antibody production with an exponential timecourse, peaking after about one month. Vimang significantly inhibited this antibody production from about three weeks post-inoculation, and most markedly by four weeks post-inoculation; by contrast, mangiferin had no significant effect. Determination of Ig isotypes showed that the IgM to IgG switch began about four weeks post-inoculation, with IgG2a predominating. Vimang significantly inhibited IgG production, but had no effect on IgM. Mangiferin did no affect either IgM or IgG2a, but significantly enhanced production of IgG1 and IgG2b. Neither Vimang nor mangiferin enhanced specific antibody secretion by splenic plasma cells from mice inoculated with microsporidian spores, whether administered in vivo before serum extraction or in vitro to the culture medium. Inoculation with spores induced splenomegaly, which was significantly reduced by Vimang and significantly enhanced by mangiferin. These results suggest that components of Mangifera indica extracts may be of potential value for modulating the humoral response in different immunopathological disorders.

Adjuvants, Immunologic↗

PubMed2004

Antimycobacterial constituents from Juniperus procera, Ferula communis and Plumbago zeylanica and their in vitro synergistic activity with isonicotinic acid hydrazide.

The synergistic activity of antimycobacterial constituents from Saudi plants was evaluated in combination with isonicotinic acid hydrazide (INH) against four atypical organisms, namely, Mycobacterium intracellulare, M. smegmatis, M. xenopei and M. chelonei. The potency of INH was increased four-fold, using an in vitro checkerboard method, against each mycobacteria when tested with a subtoxic concentration of the totarol, isolated from J. procera. The MIC values of totarol, ferulenol (from Ferula communis) and plumbagin (from Plumbago zeylanica) were thus lowered from 1.25-2.5 to 0.15-0.3 microg/mL due to synergism with INH. When tested against the resistant strain of M. tuberculosis H37Rv, plumbagin and 7beta-hydroxyabieta-8,13-dien-11,12-dione exhibited inhibitory activity at <12.5 microg/mL, while others were inactive at this concentration.

Antitubercular Agents↗

PubMed2005

In Vitro culture studies of FlorEssence on human tumor cell lines.

FlorEssence (FE) is an herbal tea widely used by patients to treat chronic conditions in North America, particularly cancer patients during chemo- and radiation therapy. Although individual components of FE have antioxidant, antiestrogenic, immunostimulant and antitumor properties, in vitro evidence of anticancer activity for the herbal tea itself is still lacking. We studied the antiproliferative effect of FE on MCF7 and MDA-MB-468 human breast cancer, and Jurkat and K562 leukemia cell lines. We found that FE significantly inhibited the proliferation of both breast and leukemia cells in vitro only at high concentrations, with 50% inhibition of MDA-MB-468 cells at about 1[sol ]20 dilution, Jurkat cells at about 1[sol ]10 dilution and MCF7 and K562 cells at less than 1[sol ]10 dilution. Flow cytometry analysis showed that treatment with a high concentration of FE induced G2[sol ]M arrest in MCF7 and Jurkat cells, with also an increased SubG0[sol ]G1 fraction in MCF7 cells. MDA-MB-468 cells showed a significantly increased Sub G0[sol ]G1 fraction after treatment with 1[sol ]10 dilution of FE while the cell cycle of K562 was unaffected. When MCF7 and MDA-MB-468 breast cancer cells were treated with a combination of FE with either paclitaxel or cisplatin, results showed that only the combination of 1[sol ]20 dilution of FE with 0.5 microM cisplatin resulted in a small but significantly higher MCF7 cell survival than 0.5 microM cisplatin treatment alone. FE at 1[sol ]20 and 1[sol ]50 dilutions did not affect the antiproliferative properties of these two commonly used chemotherapeutic agents. The results suggest that FE at high concentrations show differential inhibitory effect on different human cancer cell lines. Further studies are needed to assess the biological activities of FE.

Antineoplastic Agents, Phytogenic↗

PubMed2005

Effects of Khaya grandifoliola on red blood cells and bone mineral content in rats.

The therapeutic efficacy of a crude water extract of Khaya grandifoliola has been established in mice. This study was designed to assess the effect of the extract on the red blood cells and bone for 7 days, 3 weeks and a recovery period of 3 weeks. Daily administration of the extract showed no related adverse effects on the mortality rate, physical appearance or behaviour of the rats. A general pattern of significant (p < 0.5) increases in the red blood cell (RBC) count, PCV, haemoglobin and plasma iron content was shown by groups administered with extract after 7 and 21 days when compared with control rats. There was a general trend of reduction in the bone minerals determined (Ca, P, Mg and Cu) in the extract administered groups. Significant (p < 0.5) decreases were observed at the 500 mg/kg concentration. The bone potassium and iron content was significantly (p < 0.5) increased in rats administered with extract in a dose-dependent manner. There was an observed significant (p < 0.5) decrease in alkaline phosphatase (ALP) activity in the rats administered with the extract when compared with the control animals. During the recovery period, the haematological indices regressed to values which were still significantly (p < 0.5) higher than those of the control values. These results indicate that K. grandifoliola has a positive effect on erythropoeisis, but no significant effect on bone mineral contents at therapeutic doses. At extremely high doses and during prolonged administration, it may have an adverse effect on bone minerals.

Alkaline Phosphatase↗

PubMed2006

Antimicrobial, resistance-modifying effects, antioxidant and free radical scavenging activities of Mezoneuron benthamianum Baill., Securinega virosa Roxb. &Wlld. and Microglossa pyrifolia Lam.

Mezoneuron benthamianum, Securinega virosa and Microglossa pyrifolia are used in folk medicine in Ghana for the treatment of dermal infections and wounds. Petroleum spirit, chloroform and ethanol extracts of the plants were tested for antimicrobial activity against a battery of organisms using the agar well diffusion technique and a serial dilution microassay. The resistance modifying activities of these extracts on standard antibiotics against Staphylococcus aureus possessing efflux mechanisms of resistance have also been assessed. A 4-fold potentiation of the activity of norfloxacin was observed for ethanol and chloroform extracts of M. benthamianum and S. virosa, respectively, whilst the petroleum spirit extract resulted in a 2-fold potentiation with minimum inhibitory concentration (MIC) values in the range 8-16 microg/mL. Ethanol extracts of all three species, the petroleum spirit extract of M. benthamianum and the chloroform extracts of M. benthamianum and S. virosa, showed interesting antimicrobial activities. Antioxidant and free radical scavenging activities using DPPH spectrophotometric and TBA lipid peroxidation assays were also conducted. Of the five extracts that showed antioxidant activities, the petroleum spirit and chloroform extracts of M. benthamianum rated most highly by displaying strong free radical scavenging activity with IC50 values of 15.33 and 19.72 microg/mL, respectively. Lipid peroxidation inhibition provided by the same two extracts also produced the lowest IC50 values for all the extracts tested, of 23.15 and 30.36 microg/mL. These findings therefore give some support to the ethnopharmacological use of the plants in the treatment of various skin diseases and wounds, as well as demonstrating the potential of some of the plants as sources of compounds possessing the ability to modulate bacterial multidrug resistance.

Animals↗