Catechin metabolites after intake of green tea infusions

Green tea contains relatively large amounts of catechins, that have been recognized to be efficient free-radical scavengers. In spite of a largely described antioxidant effect, the metabolic fate of catechins in humans has been scarcely studied. An infusion of green tea (about 400 mg of catechins) was given to healthy volunteers; plasma and urine samples were collected for 5 h and 2 days, respectively. Epigallocatechin gallate and epicatechin gallate were detected in plasma samples, reaching the maximum concentration (2 microM) at 2 h. Urine samples collected at 6-48 h contained detectable amounts of final catechin metabolites, including 4-hydroxybenzoic acid, 3,4-dihydroxybenzoic acid, 3-methoxy-4-hydroxy-hippuric acid and 3-methoxy-4-hydroxybenzoic acid (vanillic acid). The total content of these metabolites averaged 60 mg. The levels of free plasma catechins account only partly for the increased (approximately +20%) total radical-trapping antioxidant parameter (TRAP) detected after green tea intake. Catechin conjugates (glucuronide and sulphate) and metabolites may add further contribution and explain the measured TRAP increase.

[Observations on organic components of thermal mud: morphohistochemical and biochemical studies on lipid components of mud of the Terme dei Papi (Laghetto del Bagnaccio, Viterbo). Chemical bases of the interpretation of biological and therapeutic actions of thermal mud]

In previous findings the lipidic fractions extracted acc. to Folch from the mature muds of the majority of the Italian thermal springs hot baths was studied, with the aim to identify the organic substrates of their therapeutical activity. The organic components of the "mature" peloids are produced by the metabolism of the microphytozooplankton growing spontaneously in the clay-substrate, in contact with the hot water. The Popes thermal springs (Bagnaccio's Lake) are characterised by an unique environmental situation, because the muds are naturally matured in the hot thermal water, but not in artificial baths. The morphohistochemical aspects of thermal algae growing in the Bagnaccio's lake have been studied by means of Computerised Optic Probe Video-Microscopy, using a not contact zoom objective 70-400x. Peloid types, both the "white" and the "black" contains yellow pigments, fragments of hyphae, monocellular algae, Diatomeae, Cyanophyceae and few other species. The biochemical aspects of the muds extracts are characterised by the presence of Phospholipids (PC, PE, PS, SP), a series of Hydrocarbons ranging from C30 to C38, Phytosterols (beta-sitosterol, Campesterol, Stigmasterol and traces of Cholesterol), Free Fatty Acids (Palmitic, Palmitoleic, Myristic, Stearic, Oleic and Linoleic, heptadecenoic and heptadecanoic) and Terpenes (beta-amirrhyne, 24-methylene-cyclo-arthanole). In our opinion, the therapeutic effects of the mature muds are related to its organic components, with special regards to Phospholipids, Phytosterols and Terpenes. The richness of these components in the Popes Thermal springs seems to be great interest in the dermatological and cosmetic applications, other then the traditional use.

Anti-proliferative activity of a new class of taxanes (14beta-hydroxy-10-deacetylbaccatin III derivatives) on multidrug-resistance-positive human cancer cells

Paclitaxel, docetaxel and a series of new analogs synthesized from 14beta-hydroxy-10-deacetylbaccatin III (14-OH-DAB), a natural diterpene closely related to the core synthon of the 2 above prototypes, were tested in vitro for their growth-inhibitory activity on different human cancer cell lines, including some expressing the classic multidrug-resistant (MDR) phenotype (MCF-7 ADRr and CEM VBLr). The 14-OH-DAB derivatives showed enhanced anti-proliferative activity as compared to the parent compounds on the MDR-positive cancer cell lines. Particularly, IDN 5109 showed a 25- to 30-fold higher activity than paclitaxel. The fold change in activity between paclitaxel and analogs (IC50 paclitaxel/IC50 analogs) on the MDR-positive cell lines was calculated and a significant correlation observed. As far as the MDR-negative MDA-MB 231 cells are concerned, docetaxel and IDN 5109 exhibited a more potent activity than paclitaxel. On the basis of the data obtained on cell growth inhibition, we selected the most active compounds to study their effect on the cell cycle. Cell cycle analysis showed that all of the compounds tested were able to induce cell cycle block at G2/M in a concentration-dependent manner. The amount of cell block, measured as a G1/G2 ratio, was correlated significantly (p < 0.001) with apoptosis, as evaluated in the sub-G1 region (% of DNA fragmentation), thereby suggesting that the G2/M-blocked cells underwent apoptosis. To confirm the occurrence of apoptosis in this system, DNA gel agarose electrophoresis was performed and showed the typical ladder pattern.

Synergistic antiproliferative activity of tamoxifen and docetaxel on three oestrogen receptor-negative cancer cell lines is mediated by the induction of apoptosis

The taxanes are a promising family of anti-tumour drugs that block cell cycle replication by interfering with the microtubule network. The clinical use of these drugs involves some problems related to their low solubility and occurrence of resistance, which is mainly dependent on the multidrug-resistant (MDR) phenotype. To investigate the possible interaction between docetaxel and tamoxifen (TAM), three oestrogen receptor-negative cancer cell lines, MDR- MDA-MB 231, MDR + CEM-VBLr and MCF-7 ADRr, were used. In all three cell lines, the combination of docetaxel and TAM was more effective in terms of growth inhibition than single drug exposure. Isobolic analysis confirmed the presence of synergism in all cell lines when docetaxel was used at 0.2 microM and TAM at a dose equal to or higher than 1 microM. Flow cytometric DNA analysis performed on the three cell lines showed that TAM was able to increase the G2/M blocking activity of docetaxel. This blocking activity was followed by an increased flow cytometric DNA fragmentation suggestive of the presence of apoptosis, which was confirmed by DNA gel fragmentation and morphological analysis. While an antagonistic effect on P-glycoprotein (P-gp) activity may contribute to the synergistic effect of tamoxifen and docetaxel on CEM-VBLr and MCF-7 ADRr, other mechanisms must be involved, as the synergistic effect is also apparent with a P-gp-negative cell line.

Procyanidines from Vitis vinifera seeds protect rabbit heart from ischemia/reperfusion injury: antioxidant intervention and/or iron and copper sequestering ability

An isolated rabbit heart Langendorff preparation paced electrically was used to evaluate the effects of a highly purified, high molecular weight fraction of oligomeric procyanidines isolated from Vitis vinifera seeds on myocardial reperfusion injury after 40 minutes of low flow (1 ml/min) ischemia. Infusion of the heart with 100 or 200 micrograms/ml procyanidines dose-dependently reduced ventricular contracture during ischemia (LVEDP values decreased by 28% and 51%), decreased coronary perfusion pressure (CPP), improved cardiac mechanical performance upon reperfusion, increased the release of 6-keto-PGF1 alpha into the perfusate in both the pre-ischemic and the reperfusion periods (by 68% at 200 micrograms/ml), and suppressed rhythm irregularity. This antiarrhythmogenic action was confirmed in a more severe model of ischemia (flow rate 0.2 ml/ min). The cardioprotective agent allopurinol infused at 20 micrograms/ml had effects on the contractility and on the release of 6-keto-PGF1 alpha comparable to those of 200 micrograms/ml procyanidines. The results of the second part of this study show that procyanidines are potent scavengers of several reactive oxygen species involved in the ischemia/reperfusion damage: the superoxide anion (IC50 = 5.64 microM: rate constant K = 7.55 x 10(5) M-1 s-1, determined by the phenazine methosulfate/NADH method); the hydroxyl radical (IC50 = 28 microM; rate constant K = 1.2 x 10(12) M-1 s-1, determined by the electron spin resonance spectroscopy); peroxyl radicals (IC50 = 0.025 microM and 0.35 microM, determined using two different lipid substrates, phosphatidylcholine liposomes and methyl linoleate micelles by UV spectroscopy at 233 nm). Finally, procyanidines interact with Fe2+ and Cu2+ ions (the catalysts of HO. radicals production) giving rise to strong complexes, with stability constants (log K) ranging from 9.35 to approximately 9.

Antiproliferative effect of silybin on gynaecological malignancies: synergism with cisplatin and doxorubicin

The aim of this study was to test the antiproliferative activity of silybin, a flavonoid, on human ovarian and breast cancer cell lines. Since flavonoids are thought to act through Type II oestrogen binding sites (Type II EBS), silybin binding to Type II EBS was also examined. Silybin, used in concentrations from 0.1 to 20 microM, exerted a dose-dependent growth inhibitory effect on OVCA 433, A2780 parental and drug-resistant ovarian cancer cells, and MCF-7 doxorubicin (DOX)-resistant breast cancer cells (IC50 = 4.8-24 microM). Both L and D diastereoisomers of silybin were effective in inhibiting A2780 WT cell growth (IC50 = 14 and 20 microM, respectively). Flow cytometry revealed that silybin decreased the percentage of cells in the S and G2-M phases of the cell cycle with a concomitant increase in cells in the G0-G1 phase. Silybin was able to compete with [3H]E2 for nuclear but not cytosolic Type II EBS. Its affinity parallels its efficacy in inhibiting cell proliferation. Furthermore, silybin (0.1 and 1 microM) potentiates the effect of cisplatin (CDDP) (0.1-1 micrograms/ml) in inhibiting A2780 WT and CDDP-resistant cell growth. Similar results were obtained on MCF-7 DOX-resistant cells when silybin (0.1 microM) was associated with doxorubicin (0.1-10 micrograms/ml). As assessed by the Berembaum isobole method, the effect of silybin-CDDP and silybin-DOX combinations results in a synergistic action. Using the 'stem cell assay' described by Hamburger and Salmon [Science 1977, 197, 461-463], we found that silybin exerted a dose-dependent inhibition of clonogenic efficiency of cells derived from three ovarian tumours (IC50 = 7.4, 4 and 6.4 microM, respectively). Since CDDP and DOX are the two most commonly used drugs for gynaecological tumours, the clinical application of silybin is currently under investigation in our institute.

Anomalous behaviour of lycopene by HPLC on cyano-amino polar phase

By reversed phase HPLC the highly pure lycopene produces only one peak, that corresponds to the all-trans polyunsaturated system. Commercial standards, however, show generally two peaks that correspond to the molecule in all-trans configuration (about 90%) and probably to its 13-cis geometrical isomer (about 10%), respectively, independent of the solvent used to inject the sample. An anomalous HPLC behaviour was observed by analysing a commercial sample of lycopene by normal-phase HPLC. In this case the chromatogram showed different profiles depending on the solvent used to prepare the solution to be injected. A relationship between such unusual behaviour and the polarity of the solvent used to dissolve the sample was tentatively found. It is worth emphasizing that in the same HPLC conditions the behaviour of beta-carotene does not show the above described phenomenon.

Effects of proanthocyanidin on normal and reinnervated rat muscle

Proanthocyanidin-A2, a catechic dimer extracted from the bark of Aesculus hippocastanum L., was tested on peripheral nerve regeneration. Reinnervation of EDL and soleus muscles following traumatic nerve damage was investigated in rats by using "in vivo" tension recording technique. Muscle contraction force (twitch and tetanus), the number of motor units and the time course of twitch (time to peak and half relaxation time), were observed. The results obtained do not show that the time course of EDL and soleus muscles reinnervation is different in Proanthocyanidin-A2-treated rats in comparison to control animals. On the contrary, results point out an increase in EDL and soleus muscle mass, both in denervated and in undenervated treated rats compared to corresponding controls. Moreover, consistently with this finding, an increase in their contraction force was found. These data show that Proanthocyanidin-A2 exerts a trophic effect on muscle.

Minor taxoids from Taxus wallichiana

The needles of Taxus wallichiana afforded a new analogue of taxinine M [1a] and two derivatives of brevifoliol [2a, 3a]. The conformation of 3a was investigated by nmr spectroscopy with the aid of variable-temperature experiments and in situ reactions.

Immunorecognition of ring skeleton of taxanes by chicken egg yolk antibodies

Anti-10 deacetylbaccatin III (DAB) antibodies (IgY) were elicited in hens immunized with a succinyl-DAB/BSA conjugate and extracted from egg yolk. As shown by indirect competitive inhibition enzyme immunoassay (CIEIA), the addition of free-DAB competitively inhibited the binding of affinity purified anti-DAB IgY to DAB/BSA solid phase conjugated antigen. The assay enabled the detection of DAB in concentrations as low as 7.5ng/ml (13.7 nM DAB), whereas anti-DAB IgY did not react with taxol even at a concentration a thousand times higher. The structural requirements of the diterpenoid nucleus for binding to IgY were considered on the basis of the levels of cross-reaction found with 10 authentic taxanes. The results indicate that anti-DAB IgY represents the first high affinity antibody produced capable of recognizing the ring skeleton of taxol precursors.

Free radicals scavenging action and anti-enzyme activities of procyanidines from Vitis vinifera. A mechanism for their capillary protective action

The scavenging by procyanidines (polyphenol oligomers from Vitis vinifera seeds, CAS 85594-37-2) of reactive oxygen species (ROS) involved in the onset (HO degrees) and the maintenance of microvascular injury (lipid radicals R degrees, RO degrees, ROO degrees) has been studied in phosphatidylcholine liposomes (PCL), using two different models of free radical generation: a) iron-promoted and b) ultrasound-induced lipid peroxidation. In a) lipid peroxidation was assessed by determination of thiobarbituric acid-reactive substances (TBARS); in b) by determination of conjugated dienes, formation of breakdown carbonyl products (as 2,4-dinitrophenylhydrazones) and loss of native phosphatidylcholine. In the iron-promoted (Fenton-driven) model, procyanidines had a remarkable, dose-dependent antilipoperoxidant activity (IC50 = 2.5 mumol/l), more than one order of magnitude greater than that of the monomeric unit catechin (IC50 = 50 mumol/l), activity which is due, at least in part, to their metal-chelating properties. In the more specific model b), which discriminates between the initiator (hydroxyl radical from water sonolysis) and the propagator species of lipid peroxidation (the peroxyl radical, from autooxidation of C-centered radicals), procyanidines are highly effective in preventing conjugated diene formation in both the induction (IC50 = 0.1 mumol/l) and propagation (IC50 = 0.05 mumol/l) phases (the scavenging effect of alpha-tocopherol was weaker, with IC50 of 1.5 and 1.25 mumol/l). In addition, procyanidines at 0.5 mumol/l markedly delayed the onset of the breakdown phase (48 h), totally inhibiting during this time the formation of degradation products (the lag-time induced by alpha-tocopherol was only of 24 h at 10 mumol/l concentration). The HO degrees entrapping capacity of these compounds was further confirmed by UV studies and by electron spin resonance (ESR) spectroscopy, using DMPO as spin trapper: procyanidines markedly reduced, in a dose-dependent fashion, the signal intensity of the DMPO-OH radical spin adduct (100% inhibition at 40 mumol/l). The results of the second part of this study show that procyanidines, in addition to free radical scavenging action, strongly and non-competitively, inhibit xanthine oxidase activity, the enzyme which triggers the oxy radical cascade (IC50 = 2.4 mumol/l). In addition procyanidines non-competitively inhibit the activities of the proteolytic enzymes collagenase (IC50 = 38 mumol/l) and elastase (IC50 = 4.24 mumol/l) and of the glycosidases hyaluronidase and beta-glucuronidase (IC50 = 80 mumol/l and 1.1 mumol/l), involved in the turnover of the main structural components of the extravascular matrix collagen, elastin and hyaluronic acid.(ABSTRACT TRUNCATED AT 400 WORDS)

Immunological detection and quantitation of 10-deacetylbaccatin III in Taxus sp. plant and tissue cultures

A high-sensitive ELISA method was developed for the detection and semi-quantitative determination of 10-deacetylbaccatin III and its structurally related compounds in crude extract of Taxus sp. plants and tissue cultures. The antibodies were raised in rabbits using 7- or 10-succinyl-10-deacetylbaccatin III-BSA conjugate as immunogen. The working range of the assay was from 0.003 to 1.000 ng (0.09 to 31.33 nM) of 10-deacetylbaccatin III per assay. The cross-reacting material in crude plant extract was examined by chromatographic (silica gel CC, HPLC) and immunoassay methods. Study on the evaluation of cross-reacting material in crude Taxus plant extracts showed that at least 80% of the immunosignal correspond to 10-deacetylbaccatin III in the extract. The ELISA method was applied to investigate the 10-deacetylbaccatin III equivalent content in crude extracts of 19 plants species including Taxaceae, Taxodiaceae and Pinaceae species. The 10-deacetylbaccatin III-like structure was only detected in Taxus and Torreya sp. The results indicate that this immunoassay is a useful tool for the rapid screening of species, varieties or individual plants out of a wide population. The distribution of 10-deacetylbaccatin III equivalent content in 9-month old Taxus plantlets cultivated in vitro as well as in callus culture was investigated.

Immunoassays for the quantitative determination of colchicine

A radioimmunoassay as well as an enzyme immunoassay for the quantitation of fmol amounts of the alkaloid colchicine have been developed. The antiserum used for both assays was raised against a conjugate of colchicoside-bovine serum albumin. The crude serum was satisfactory for the performance of the radioimmunoassay. For the enzyme immunoassay, the antibodies had to be isolated and purified by Rivanol treatment with subsequent (NH4)2SO4 precipitation. The measuring range extends from 0.1 to 100 ng colchicine for the radioimmunoassay and from 0.05 to 350 ng for the enzyme immunoassay with detection limits of 125 fmol and 25 fmol, respectively. Both immunoassays cross reacted with colchicoside and 3-demethyl-colchicine up to 80%. The colchicine content in the newly established suspension culture of Colchicum variegatum as well as the influence of various culture media on the colchicine production of this cell culture were investigated with the radioimmunoassay. The enzyme immunoassay was well suited for the quantitation of colchicine in HPLC fractions of Gloriosa and Colchicum seed extracts allowing the rapid, sensitive, and precise determination of the substance under investigation. The preliminary experiments indicate that both colchicine immunoassays can be a useful tool for the analysis of colchicine in tissue and cell culture studies, for analysis of plant extracts as well as for biosynthetic investigations.

Morphological analysis on the adrenal zona fasciculata of Ginseng, Ginsenoside Rb1 and Ginsenoside Rg1 treated mice

Morphological analysis was performed on the adrenal cortex of depressed mice which received repeated administrations of Ginseng extract or Ginsenoside Rb1 or Ginsenoside Rg1 in order to follow the behaviour of the gland. The left gland was fixed for usual stains and cell measurements of both treated and control adrenal cortex were made on twenty central sections. The outlines of cells from the zona fasciculata, in which nucleus was evident, were traced at 625X using a drawing tube. Cell areas were computed from these drawings by means of image analysis (Optilab software). Our results show that: 1) Ginseng extract administration produces a significant increase in the zona fasciculata cell size with respect to controls. The distribution of soma sizes is generally to the right of the spectrum showing a considerable decrease in cells of small size and a similar increase in cells of intermediate and large size with respect to controls; 2) in Ginsenoside-administered animals, although the mean cell areas is not significantly altered, the distribution of cell sizes shows significant differences between normal and treated animals. It is commonly recognized that mean cell area is in strict connection with cell activity: therefore Ginseng extract may be thought to stimulate adrenal cell activity while the two Ginsenosides have an effect which do not lead to significant changes in mean cell size.

Regeneration of motor nerves in bilobalide-treated rats

Bilobalide, a terpene extracted from the leaves of the Ginkgo biloba tree, has been proposed to exert trophic and protective effects on neurons and on Schwann's cells in various neuropathies. The reinnervation of the extensor digitorum longus muscle following traumatic nerve damage was investigated in rats by using electrophysiological and histological techniques. Evaluation parameters included the membrane resting potential of muscle cells, the spontaneous quantal release of acetylcholine, and the percentage of muscle cells receiving multiple innervation. The percentage of muscle cells receiving multiple innervation reached a peak more rapidly in treated animals and declined subsequently to values lower than those found in controls. These data suggest that the rearrangement of regenerated innervation occurs more rapidly in bilobalide-treated animals.

Activity of bilobalide, a sesquiterpene from Ginkgo biloba, on Pneumocystis carinii

The sesquiterpene bilobalide, extracted from Ginkgo biloba leaves, was tested in vitro and in vivo for the ability to inhibit Pneumocystis carinii growth. Bilobalide was inhibitory to trophozoites cultured on human embryonic lung fibroblasts (HEL 299) at approximately the same concentration as trimethoprim plus sulfamethoxazole (lowest effective concentration, 50 micrograms of bilobalide per ml versus 9/45 microgram of trimethoprim-sulfamethoxazole per ml), inducing microscopically detectable morphological changes in the cytoplasm of the parasite. In pharmacologically immunosuppressed Sprague-Dawley rats transtracheally infected with a suspension of about 5 x 10(6) P. carinii trophozoites per ml, the daily intraperitoneal administration of bilobalide (10 mg/kg of body weight for 8 days) lowered the number of organisms by approximately 2 logs (that is, about 99%). There was no apparent toxicity either in uninfected HEL 299 feeder cells or in infected and uninfected animals. These studies suggest that the sesquiterpene bilobalide might be useful for therapy of and prophylaxis against P. carinii infections in humans.

Phytosome: new cosmetic delivery system

Modern cosmetology is increasingly alternating with dermatology as a discipline concerns the treatment of non pathological skin. One of the main problems is the transcutaneous absorption of active principles. The modern cosmetologist, is confronted with the need of findings means to facilitate the passage across skin of active products. Liposomes are artificial phospholipid membranes that can facility the passage of active principles across the stratum conneum. After the fortuitous observation that phospholipids exhibit a marked affinity for some classes of flavonoids, we have developed a new series of compounds denominate "phytosome", which we have obtained by complexation with very polar botanical derivatives. From the chemical viewpoint the PHYTOSOME are complexes between a pure phospholipid and a pure active principles. The authors realize at industrial level a certain number of that complexes. In the work are presents the chemico physical properties of complexes with catechin, quercetin, escin and glycyrrhetinic acid; some pharmacological data obtained are presented.

[Progression of multiple innervation of reinnervated rat muscle treated with bilobalide]

During motor nerve regeneration a transitory polyinnervation of muscle cells occurs, which represents a phase of rearrangement of the recovered innervation. Bilobalide, a terpene extrated from Ginkgo biloba leaves, was proposed to affect some aspects of nervous system development and regeneration. In this work, influence of bilobalide on polyinnervation in reinnervated extensor digitorum longus muscle was studied, through electrophysiological and histological techniques. The muscle was denervated crushing the sciatic nerve and it was examined at 1 or 2 months after denervation. The polyinnervated muscle cells in controls reached 24% at 1 month and thus the percentage decreased. In muscles of bilobalide treated rats the number of polyinnervated cells was decreased at both times.

Computer-aided evaluation of gastric proteoglycans by high-resolution gas chromatography

A convenient procedure is described for the simultaneous separation and identification of monosaccharides and aminomonosaccharides constituting the proteoglycans of gastric mucosa. Computer assistance was used to obtain significant information from gas chromatographic data on proteoglycan modifications induced by anti-inflammatory drugs. Glass capillary chromatography was used for the separation and identification of saccharides and aminomonosaccharides of hydrolyzed mucus samples scraped from the stomachs of control and treated rats. The data, transmitted to a 48 K personal computer, were processed to obtain three-dimensional probability density functions or subjected to factor analysis to evaluate the suitability of the method to evidence modifications at the proteoglycan level induced by drugs, orally administered to rats. Indomethacin, zolimidine and acetylsalicylic acid were used as models for the applications.

[Anthocyanosides and the walls of the microvessels: further aspects of the mechanism of action of their protective effect in syndromes due to abnormal capillary fragility]

On the basis of previous biochemical observations, which have demonstrated the formation of complexes between anthocyanosides and some phospholipids, the AA. investigate the modifications induced by local and general administration of anthocyanosides 1) on the foreign body granuloma and 2) on the composition of the protein fractions in the exudate from the capillaries of the granulation tissue, growing on post-thromboflebitic or varicose leg ulcerations. The biochemical and histochemical data may show that the anthocyanosides protect the altered capillary walls with a double mechanism: a) increasing the endothelium barrier-effect through a stabilisation of the membrane phospholipids and b) increasing the biosynthetic processes of the acid mucopolysaccharides of the connective ground substance, by restoring the altered mucopolysaccharidic pericapillary sheat. This last effect may explain the marked increase of new-formed capillaries and collagen fibrils induced by the anthocyanosides.

In vitro and in vivo observations on the erythrocyte uptake of 17-monochloroacetylajmaline

The in vitro and in vivo observations on the uptake rate of 17-monochloroacetylajmaline by human erythrocytes showed that about 30-35% of the drug is bound to red blood cells. These findings suggest a peculiar affinity of the drug for the erythrocytes, may be for the membrane or stromal phospholipids.