Comprehensive review on herbal medicine for energy intake suppression.

The obesity drug development is present not a bright and successful story. So far, drugs reported to be effective, either from synthetic or natural sources, mostly stimulated controversy because of serious adverse effects, which ended with stopping clinical trials or even withdrawal from the market. However, obesity and its comorbidities have become rapidly a major problem in both developed and developing countries. This has encouraged pharmaceutical companies and academia to keep on struggling on developing novel effective but safe obesity drugs, and on characterizing novel obesity drug targets. From existing scientific work on obesity drug discovery and commercial slimming preparations, compounds originating from nature, especially from plants, seem to be the first choice. Traditional belief that herbal medicine is safer than synthetic ones is one of the classical arguments, although scientifically this is not always true (e.g. ban on Ephedra). But in general, it has been widely acknowledged that a plant compound, with its unique scaffolds and rich diversity is an unlimited source of novel lead compounds. This paper aims to summarize all works focused on screening plant materials by targeting important pathways related to energy intake regulation, either by in vivo or in vitro experiments.

Cannabis smoke condensate III: the cannabinoid content of vaporised Cannabis sativa.

Cannabis sativa is a well-known recreational drug and, as such, a controlled substance of which possession and use are illegal in most countries of the world. Due to the legal constraints on the possession and use of C. sativa, relatively little research on the medicinal qualities of this plant has been conducted. Interest in the medicinal uses of this plant has, however, increased in the last decades. The methods of administration for medicinal purposes are mainly through oral ingestion, smoking, and nowadays also inhalation through vaporization. During this study the commercially available Volcano vaporizing device was compared with cannabis cigarette smoke. The cannabis smoke and vapor (obtained at different temperatures) were quantitatively analyzed by high-performance liquid chromatography (HPLC). In addition, different quantities of cannabis material were also tested with the vaporizer. The cannabinoids:by-products ratio in the vapor obtained at 200 degrees C and 230 degrees C was significantly higher than in the cigarette smoke. The worst ratio of cannabinoids:by-products was obtained from the vaporized cannabis sample at 170 degrees C.

Commentary: "A systems view on the future of medicine: inspiration from Chinese medicine?".

Chinese medicine could serve as a source of inspiration for drug development. Using systems biology in combination with reverse pharmacology is a novel way for the discovery of novel biological active compounds and targets as well as for proving the occurrence of synergy and prodrugs. A key factor for coming to evidence-based Chinese medicine will be the quality control. Metabolomics is a very promising tool for this purpose.

Ethnopharmacology and systems biology: a perfect holistic match.

Traditional medical doctors often apply a holistic approach in prescribing medicines to the patient. Each individual patient gets his own optimalized medicine, usually a mixture of different ingredients. The present day paradigm of drug development of , is based on a super reductionist approach which involves mostly tests of compounds at the molecular level in, e.g., receptor binding assays. This approach is not the best for studies on traditional medicines. A more holistic approach using systems biology seems much more suited to proof efficacy and to obtain information that might lead to understanding the mode of action. Synergy, prodrugs, novel targets, all these might be detected by a systems biology approach whereas the reductioinist approach only will recognize activity on already known targets, and will not detect synergism and prodrugs. Metabolomics will be a major tool in recognizing compounds connected with activity in the traditional medicines, and will also be very useful in recognizing the effect on the test organism, which can be the patient in case of clinical trials with well established traditional medicines.

Bioactive constituents of Leptadenia arborea.

The aerial part of Leptadenia arborea has been shown to contain pinoresinol (1), syringaresinol (2), leucanthemitol (3) and E-ferulaldehyde (4). These known compounds are being reported for the first time from this plant. Among them, syringaresinol has shown an inhibitory effect against acetylcholinesterase. The IC(50) (the concentration of 50% enzyme inhibition) value of this compound was 200 microg/ml.

Anti-inflammatory, antipyretic and antinociceptive activities of Tabernaemontana pandacaqui Poir.

Studies on carrageenin-induced rat paw edema, yeast-induced hyperthermia in rat and writhing response induced by acetic acid in mice showed that the alcoholic extract of stems of Tabernaemontana pandacaqui (T. pandacaqui) has significant anti-inflammatory, antipyretic and antinociceptive activities. These activities are due to alkaloidal components since they were also observed when the crude alkaloidal (CA) fraction separated from alcoholic extract was tested in the same models.

Somaclonal variation: a morphogenetic and biochemical analysis of Mandevilla velutina cultured cells.

Cell cultures of Mandevilla velutina have proved to be an interesting production system for biomass and secondary metabolites able to inhibit the hypotensive activity of bradykinin, a nonapeptide generated in plasma during tissue trauma. The crude ethyl acetate extract of cultured cells contains about 31- to 79-fold more potent anti-bradykinin compounds (e.g., velutinol A) than that obtained with equivalent extracts of tubers. Somaclonal variation may be an explanation for the wide range of inhibitor activity found in the cell cultures. The heterogeneity concerning morphology, differentiation, carbon dissimilation, and velutinol A production in M. velutina cell cultures is reported. Cell cultures showed an asynchronous growth and cells in distinct developmental stages. Meristematic cells were found as the major type, with several morphological variations. Cell aggregates consisting only of meristematic cells, differentiated cells containing specialized cell structures such as functional chloroplasts (cytodifferentiation) and cells with embryogenetic characteristics were observed. The time course for sucrose metabolism indicated cell populations with significant differences in growth and metabolic rates, with the highest biomass-producing cell line showing a cell cycle 60% shorter and a metabolic rate 33.6% higher than the control (F2 cell population). MALDI-TOF mass spectrometric analysis of velutinol A in selected cell lines demonstrated the existence of velutinol A producing and nonproducing somaclones. These results point to a high genetic heterogeneity in general and also in terms of secondary metabolite content.

Somaclonal variation: a morphogenetic and biochemical analysis of Mandevilla velutina cultured cells

Cell cultures of Mandevilla velutina have proved to be an interesting production system for biomass and secondary metabolites able to inhibit the hypotensive activity of bradykinin, a nonapeptide generated in plasma during tissue trauma. The crude ethyl acetate extract of cultured cells contains about 31- to 79-fold more potent anti-bradykinin compounds (e.g., velutinol A) than that obtained with equivalent extracts of tubers. Somaclonal variation may be an explanation for the wide range of inhibitor activity found in the cell cultures. The heterogeneity concerning morphology, differentiation, carbon dissimilation, and velutinol A production in M. velutina cell cultures is reported. Cell cultures showed an asynchronous growth and cells in distinct developmental stages. Meristematic cells were found as the major type, with several morphological variations. Cell aggregates consisting only of meristematic cells, differentiated cells containing specialized cell structures such as functional chloroplasts (cytodifferentiation) and cells with embryogenetic characteristics were observed. The time course for sucrose metabolism indicated cell populations with significant differences in growth and metabolic rates, with the highest biomass-producing cell line showing a cell cycle 60 percent shorter and a metabolic rate 33.6 percent higher than the control (F2 cell population). MALDI-TOF mass spectrometric analysis of velutinol A in selected cell lines demonstrated the existence of velutinol A producing and nonproducing somaclones. These results point to a high genetic heterogeneity in general and also in terms of secondary metabolite content

CNS active potentials of some Hypericum species of India.

Hypericum is a large genus comprising 200 species, wide spread on temperate region and tropical mountains. Several different species are available in Indian subcontinent. Psychopharmacological profiles of the two different Hypericum species e.g., H. hookerianum and H. patulum available in Nilgiris, India were investigated at two different doses (200 and 400 mg/kg, p.o.) in different animal models viz. Spontaneous motor activity (SMA) test in mice; Exploratory behaviour test by Head dip test in mice and Y-maze test in rats; Effects on pentobarbitone induced sleeping time in mice and study of the effects on body temperature in rats. All the extracts tested showed enhancement in spontaneous motor activity (SMA) in mice and exploratory behavior by head dip test in mice and Y-maze test in rats. The extracts reduce significantly the pentobarbitone induced sleeping time in mice. When tested for their effect on body temperature in rats, the extract of H. hookerianum showed significant reduction in yeast induced pyrexia with no effect on normal body temperature, while H. patulum showed no activity in this experimental model.

beta-Glucosidase and peroxidase stability in crude enzyme extracts from green beans of Vanilla planifolia Andrews.

The extraction method for beta-glucosidase from green vanilla beans has been studied. The effect of storage of green beans and protein extracts on beta-glucosidase and peroxidase activity was investigated: the best method, resulting in the highest enzyme activities, particularly for glucosidase, was through extraction of very fresh green beans in the presence of BisTris propane buffer at pH 8. The best method for storage of the extracts was at -80 degrees C after addition of 15% glycerol, when over 90% of initial activity was still present. Peroxidase activity did not change in frozen beans or in frozen extracts.

Isolation of a bronchodilator flavonoid from the Thai medicinal plant Clerodendrum petasites.

The ethanolic extract of Clerodendrum petasites was tested to evaluate the spasmolytic activity on isolated guinea-pig tracheal smooth muscle. The crude extract (2.25-9.0 mg/ml) dose-dependently caused relaxation of tracheal smooth muscle which was contracted by exposure to histamine. A bioassay-guided fractionation of the crude extract was performed by means of partitioning and centrifugal partition chromatography. Finally the active principle was isolated and identified as the flavonoid hispidulin (EC(50): (3.0+/-0.8)x10(-5) M). These results suggest that hispidulin may be beneficial in the treatment of asthma.

Biotransformation of tryptamine and secologanin into plant terpenoid indole alkaloids by transgenic yeast.

A transgenic Saccharomyces cerevisiae was constructed containing the cDNAs coding for strictosidine synthase (STR) and strictosidine beta-glucosidase (SGD) from the medicinal plant Catharanthus roseus. Both enzymes are involved in the biosynthesis of terpenoid indole alkaloids. The yeast culture was found to express high levels of both enzymes. STR activity was found both inside the cells (13.2 nkatal/g fresh weight) and in the medium (up to 25 nkatal/l medium), whereas SGD activity was present only inside the yeast cells (2.5 mkatal/g fresh weight). Upon feeding of tryptamine and secologanin, this transgenic yeast culture produced high levels of strictosidine in the medium; levels up to 2 g/l were measured. Inside the yeast cells strictosidine was also detected, although in much lower amounts (0.2 mg/g cells). This was due to the low permeability of the cells towards the substrates, secologanin and tryptamine. However, the strictosidine present in the medium was completely hydrolyzed to cathenamine, after permeabilizing the yeast cells. Furthermore, transgenic S. cerevisiae was able to grow on an extract of Symphoricarpus albus berries serving as a source for secologanin and carbohydrates. Under these conditions, the addition of tryptamine was sufficient for the transgenic yeast culture to produce indole alkaloids. Our results show that transgenic yeast cultures are an interesting alternative for the production of plant alkaloids.

Sequential solubilization of proteins precipitated with trichloroacetic acid in acetone from cultured Catharanthus roseus cells yields 52% more spots after two-dimensional electrophoresis.

Sample preparation is still the most critical step in two-dimensional gel electrophoresis (2-DE), and needs to be optimized for each type of sample. To analyze the proteome of the medicinal plant Catharanthus roseus, we developed and evaluated a sequential solubilization procedure for the solubilization of proteins after precipitation in trichloroacetic acid and acetone. The procedure includes solubilization with a conventional urea buffer followed by a stronger solubilizing buffer containing thiourea. The sequential solubilization of the precipitated proteins results in very different spot patterns following 2-DE. The number of protein spots which could be detected in both samples of the sequential solubilization was only about 10% of the total number of spots. Compared to solubilization in a single step, the total number of spots that could be detected in the sequential solubilization procedure was increased by 52%. The method described is simple and is applicable to different types of plant tissue.

Evaluation of in-vivo wound healing activity of Hypericum patulum (Family: hypericaceae) leaf extract on different wound model in rats.

The methanol extract of Hypericum patulum Thumb. leaves were investigated for the evaluation of their wound healing potential on different experimental models of wounds in rats. The methanol extract of leaves (HPM), in the form of an ointment with two different concentrations (5% and 10% w/w ointment of leaf extract in simple ointment base) was evaluated for wound healing potential in an excision wound model and an incision wound model in rats. Both concentrations of the methanol extract ointment showed significant responses in both the wound types tested when compared with the control group. The effect produced by the extract ointment, in terms of wound contracting ability, wound closure time, regeneration of tissues at wound site, tensile strength of the wound and histopathological characteristics were comparable to those of a standard drug nitrofurazone ointment.

Luteolin, a compound with adenosine A(1) receptor-binding activity, and chromone and dihydronaphthalenone constituents from Senna siamea.

Activity-guided fractionation led to the isolation of luteolin (1) from the leaves of Senna siamea (syn. Cassia siamea). This compound was found to be an antagonist at the adenosine A(1) receptor with a K(i) value in the low micromolar range. Four additional nonactive compounds (2-5) were also isolated, and their structures were elucidated. One compound was identified as cassia chromone (5-acetonyl-7-hydroxy-2-methylchromone) (2). Three other compounds are new, and they were identified as 5-acetonyl-7-hydroxy-2-hydroxymethyl-chromone (3), 4-(trans)-acetyl-3,6,8-trihydroxy-3-methyldihydronaphthalenone (4), and 4-(cis)-acetyl-3,6,8-trihydroxy-3-methyldihydronaphthalenone (5).

High-performance liquid chromatography with on-line coupled UV, mass spectrometric and biochemical detection for identification of acetylcholinesterase inhibitors from natural products.

A high-performance liquid chromatography (HPLC) method with on-line coupled ultraviolet (UV), mass spectrometry (MS) and biochemical detection for acetylcholinesterase (AChE) inhibitory activity has been developed. By combining the separation power of HPLC, the high selectivity of biochemical detection, and the ability to provide molecular mass and structural information of MS, AChE inhibitors can be rapidly identified. The biochemical detection was based on a colorimetric method using Ellman's reagent. The detection limit of galanthamine, an AChE inhibitor, in the HPLC-biochemical detection is 0.3 nmol. The three detector lines used, i.e., UV, MS and Vis for the biochemical detection were recorded simultaneously and the delay times of the peaks obtained were found to be consistent. This on-line post-column detection technique can be used for the identification of AChE inhibitors in plant extracts and other complex mixtures such as combinatorial libraries.

Interference of linoleic acid fraction in some receptor binding assays.

An extract of a suspension culture of Tabernaemontana pandacaqui Poir. was fractionated by centrifugal partition chromatography. Aliquots were tested in an adenosine A1 receptor binding assay. This led to the isolation and identification of linoleic acid, which proved to be a noncompetitive inhibitor. This "false positive"effect also extended to some other binding assays.

Isolation of opioid-active compounds from Tabernaemontana pachysiphon leaves.

A procedure for prefractionation of crude plant extracts by centrifugal partition chromatography (CPC) has been developed to enable rapid identification of known-positive compounds or false-positive compounds and to increase the chance of identifying minor unknown-active compounds. The study explored the use of CPC as a tool in the prefractionation step before investigation of bioactivity. Fractions obtained by CPC from an ethanolic extract of Tabernaemontana pachysiphon Stapf (Apocynaceae) were screened by means of an opiate-receptor-binding assay and an adenosine A1-receptor-binding assay. Fractions containing fatty acids, which had false-positive effects on the assay, were identified, as were unknown-positive fractions from which two opioid-active compounds, tubotaiwine and apparicine, were subsequently isolated. The affinities (Ki) of tubotaiwine and apparicine at the opiate receptor were 1.65 +/- 0.81 and 2.65 +/- 1.56 micromol, respectively. Both alkaloids had analgesic activity in the abdominal constriction test in mice. CPC prefractionation led to the rapid isolation of two opioid-active compounds, tubotaiwine and apparicine, from the unknown-positive fraction; false-positive fractions were rapidly identified. Both tubotaiwine and apparicine had affinity for adenosine receptors in the micromolar range and also had in-vivo analgesic activity in mice.