procyanidin-b1 and procyanidin

Flavan-3-ols are abundant polyphenols in human nutrition and are associated with beneficial health effects. The aim of this study was to comparatively investigate the metabolic fate of (-)-epicatechin, procyanidin B1, and polymeric procyanidins in a randomized cross-over study in humans.. Parent compounds, conjugates, and microbial metabolites were determined in plasma, urine, and faeces by HPLC-MS and GC-MS/MS. Glucuronidated, sulfated, and methylated (-)-epicatechin and 5-(3',4'-dihydroxyphenyl)-valerolactone were the dominant metabolites in blood and urine. In addition, minor amounts of procyanidin B1 and 4-hydroxy-5-(3',4'-dihydroxyphenyl)valeric acid and their conjugated metabolites were detected. The formation of 5-(3',4'-dihydroxyphenyl)-valerolactone and 4-hydroxy-5-(3',4'-dihydroxyphenyl)valeric acid varied largely between individuals as well as with the degree of polymerization of flavan-3-ols. Monomer units were not detectable in plasma or urine after procyanidin B1 and polymeric procyanidin intake. No correlation was found between the intake of flavan-3-ols and the occurrence of phenolic acids in blood and urine or the phenolic compound profiles in faeces.. In addition to conjugated metabolites derived from the absorption of monomeric flavan-3-ols, 5-(3',4'-dihydroxyphenyl)-valerolactone represents an important in vivo metabolite of (-)-epicatechin and procyanidin B1 produced by the gut microbiota.

Topics: Adult; Biflavonoids; Body Mass Index; Cacao; Catechin; Chromatography, High Pressure Liquid; Creatinine; Cross-Over Studies; Feces; Flavonoids; Humans; Lactones; Male; Plant Extracts; Polymerization; Polymers; Polyphenols; Proanthocyanidins; Tandem Mass Spectrometry; Young Adult

To confirm the absorption of proanthocyanidin (PA) into the human body, four healthy adults were administered 2.0 g of PA-rich grape seed extract (GSE). Blood were drawn before intake and 2 h after intake. Through the enzymatic treatment of sulfatase and beta-glucuronidase, blood samples were analyzed by HPLC coupled with mass-spectrometry (LC/MS). Procyanidin B1 [epicatechin-(4beta-->8)-catechin] was detected in human serum 2 h after intake. Its concentration was 10.6 +/- 2.5 nmol/l.

Topics: Antioxidants; Biflavonoids; Catechin; Chromatography, High Pressure Liquid; Electrochemistry; Humans; Intestinal Absorption; Mass Spectrometry; Plant Extracts; Proanthocyanidins; Seeds; Vitis

Procyanidin B-2 is a compound we have identified in apple which acts as a growth-promoting factor on murine hair epithelial cells. This report describes our investigation of the hair-growing effects of 1% procyanidin B-2 tonic after sequential use for 4 months. A double-blind clinical trial was performed, involving a total of 29 subjects (procyanidin B-2, 19 men; placebo, 10 men). No adverse side effects were observed in either group. In the procyanidin B-2 group, 78.9% showed an increased mean value of hair diameter, whereas only 30.0% in the placebo group showed any increase (p < 0.02, Fisher's exact probability test). The increased ratio of hairs measuring more than 40 microm in diameter after 4 months of procyanidin B-2 treatment was significantly higher than that of the placebo controls (p < 0.05, two-sample-t-test). The increase in number of total hairs in the designated scalp area (0.25 cm(2)) of procyanidin B-2 subjects after a 4 month trial was significantly greater than that of the placebo controls (procyanidin-B-2, 3.67 +/- 4.09 (mean +/- SD)/0.25 cm(2); placebo, -2.54 +/- 4.00/0.25 cm(2); p < 0.001, two-sample t-test). Procyanidin B-2 therapy shows potential as a promising cure for male pattern baldness.

Topics: Administration, Cutaneous; Adult; Alopecia; Biflavonoids; Catechin; Hair; Humans; Male; Middle Aged; Pilot Projects; Proanthocyanidins; Scalp

Procyanidin B-2 is a polyphenol compound we have identified in apple which acts as a hair-growing factor in the murine model both in vitro and in vivo. This report describes our investigation of the effects of 1% procyanidin B-2 tonic on human hair growth after sequential use for 6 months. A double-blind clinical test involving a total of 29 subjects was performed. Nineteen men in the procyanidin B-2 group and 10 men in the placebo control group were subjected to analyses. No adverse side effects were observed in either group. The hair-growing effect was evaluated using a macrophotography technique combined with measurements of the hair diameter of clipped hairs. The increase in number of total hairs in the designated scalp area (0.5 cm square = 0.25 cm2 area) of procyanidin B-2 group subjects after the 6-month trial was significantly greater than that of the placebo control group subjects (procyanidin B-2, 6.68 +/- 5.53 (mean +/- SD)/0.25 cm2; placebo, 0.08 +/- 4.56 (mean +/- SD)/0.25 cm2; P < 0.005, two-sample t test). The increase in number of terminal hairs, which are defined as hairs more than 60 microm in diameter, in the designated area (0.5 cm square = 0.25 cm2 area) of the procyanidin B-2 group subjects after the 6-month trial was significantly greater than that of the placebo control group subjects (procyanidin B-2, 1.99 +/- 2.58 (mean +/- SD)/0.25 cm2; placebo, -0.82 +/- 3.40 (mean +/- SD)/0.25 cm2; P < 0.02, two-sample t test). Procyanidin B-2 therapy shows potential as a safe and promising cure for male pattern baldness.

Topics: Administration, Cutaneous; Adult; Alopecia; Antioxidants; Biflavonoids; Catechin; Double-Blind Method; Fruit; Hair; Humans; Male; Middle Aged; Plant Extracts; Proanthocyanidins; Scalp; Treatment Outcome

The main procyanidins, including dimeric B2 and B5, trimeric C1, tetrameric and pentameric procyanidins, were isolated from unroasted cocoa beans (Theobroma cacao L.) using various techniques of countercurrent chromatography, such as high-speed countercurrent chromatography (HSCCC), low-speed rotary countercurrent chromatography (LSRCCC) and spiral-coil LSRCCC. Furthermore, dimeric procyanidins B1 and B7, which are not present naturally in the analysed cocoa beans, were obtained after semisynthesis of cocoa bean polymers with (+)-catechin as nucleophile and separated by countercurrent chromatography. In this way, the isolation of dimeric procyanidin B1 in considerable amounts (500mg, purity>97%) was possible in a single run. This is the first report concerning the isolation and semisynthesis of dimeric to pentameric procyanidins from T. cacao by countercurrent chromatography. Additionally, the chemical structures of tetrameric (cinnamtannin A2) and pentameric procyanidins (cinnamtannin A3) were elucidated on the basis of (1)H NMR spectroscopy. Interflavanoid linkage was determined by NOE-correlations, for the first time.

Topics: Biflavonoids; Cacao; Catechin; Chromatography; Magnetic Resonance Spectroscopy; Molecular Structure; Plant Extracts; Polymers; Proanthocyanidins

Two main types of procyanidin oligomers (A-type and B-type) are present in plants. Previous studies revealed that B-type procyanidin dimers can be converted into A-type dimers by oxidation. However, the mechanism lacks experimental proof. In this study, the conditions of a B-type procyanidin trimer, procyanidin C-1 (PC-1), conversion to A-type cinnamtannin B-1 (CTB-1), including temperature, pH value and four catalysts were investigated. The catalysts include DPPH, O2(-), polyphenol oxidase and xanthine oxidase. Results show that the conversion is significantly affected by temperature and pH. Both free radicals and oxidases accelerate the conversion rate with the same products but show no increase in conversion ratio. Moreover, the isolation and identification of continuous oxidation products (P 1-P 4) from CTB-1 are discussed here. These results demonstrate that the oxidative conversion of B- to A- procyanidins in plants might involve a free radical-driven process or an enzyme-catalyzed free radical reaction via a quinone methide mechanism.

Topics: Biflavonoids; Catechin; Free Radicals; Indolequinones; Molecular Structure; Oxidation-Reduction; Proanthocyanidins

Procyanidin oligomers in Cinnamon are thought to be responsible for the biological activity in the treatment of diabetes mellitus (DM). To clarify types of procyanidin oligomers in different Cinnamon species and investigate their different effects, the present study investigated procyanidin oligomers in polyphenolic oligomer-rich extracts of three Cinnamon samples by LC-MS methods, and their hypoglycemic activities were detected in vivo and in vitro. The results showed that two of the three samples from Cinnamomum cassia were rich in B-type procyanidin oligomers, and the other sample was rich in A-type procyanidin oligomers. The Cinnamon extracts were administered at doses of 200 and 300 mg/kg body wt. in high-fat diet-fed and low-dose streptozotocin (STZ)-induced diabetic mice for 14 days. The results showed that blood glucose concentrations were significantly decreased in all Cinnamon extract groups compared with the control group (p<0.05). Administration of the Cinnamon extracts significantly increased the consumption of extracellular glucose in insulin-resistant HepG2 cells and normal HepG2 cells compared with the control group. These results suggest that both A- and B-type procyanidin oligomers in different Cinnamon species have hypoglycemic activities and may improve insulin sensitivity in type 2 DM.

Topics: Animals; Antioxidants; Biflavonoids; Blood Glucose; Catechin; Cinnamomum aromaticum; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 2; Glucose Tolerance Test; Hep G2 Cells; Humans; Hypoglycemic Agents; Insulin; Insulin Resistance; Male; Mice; Phytotherapy; Plant Bark; Plant Extracts; Plants, Medicinal; Proanthocyanidins; Streptozocin

Using a high-performance liquid chromatographic method and mass spectrometry analysis, we successfully measured the absorption of orally administered procyanidin B-2 and procyanidin B-3 isolated from Cinnamonomi cortex (the bark of Cinnamomum cassia Blume) in the rat plasma. This method used a TSK- GEL ODS-80TS column, two solvents (A: 0.01% acetic acid; B: methanol with 0.01% acetic acid) in a linear gradient at a flow-rate of 1.0 ml/min, and fluorescence detection at excitation and emission wavelengths of 220 and 327 nm.

Topics: Administration, Oral; Animals; Biflavonoids; Catechin; Chromatography, High Pressure Liquid; Cinnamomum aromaticum; Male; Mass Spectrometry; Plant Extracts; Proanthocyanidins; Rats; Rats, Wistar; Time Factors

Procyanidin fractions from apple were separated according to the degree of polymerization using normal phase chromatography. Evaluation of physiological functionalities of procyanidins requires individual structural determination. However, it is difficult to elucidate the structure of procyanidins, in particular those with (+)-epicatechin (1) or (-)-catechin (2) units, and determine whether the interflavanoid bonds are 4beta-->8 or 4beta-->6 without cleavage and acetylation. Structural determination used LC-MS and low-temperature NMR. Nine procyanidins were separated by preparative HPLC consisting of three well-known procyanidins [procyanidin B1 (3), procyanidin B2 (4), and procyanidin C1 (5)] and six new procyanidins [epicatechin-(4beta-->8)-epicatechin-(4beta-->8)-catechin (6); epicatechin-(4beta-->6)-epicatechin-(4beta-->8)-catechin (7); epicatechin-(4beta-->6)-epicatechin-(4beta-->8)-epicatechin (8); epicatechin-(4beta-->8)-epicatechin-(4beta-->6)-catechin (9); epicatechin-(4beta-->8)-epicatechin-(4beta-->6)-epicatechin (10); and epicatechin-(4beta-->8)-epicatechin-(4beta-->8)-epicatechin-(4beta-->8)-epicatechin (11)]. Compounds 6-11 were detected for the first time as apple constituents.

Topics: Biflavonoids; Catechin; Chromatography, High Pressure Liquid; Fruit; Magnetic Resonance Spectroscopy; Malus; Proanthocyanidins; Spectrometry, Mass, Electrospray Ionization; Temperature

The contribution of each phytochemical to the total antioxidant capacity of apples was determined. Major phenolic phytochemicals of six apple cultivars were identified and quantified, and their contributions to total antioxidant activity of apples were determined using a 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging assay and expressed as vitamin C equivalent antioxidant capacity (VCEAC). Average concentrations of major phenolics and vitamin C in six apple cultivars were as follows (mg/100 g of fresh weight of apples): quercetin glycosides, 13.20; procyanidin B(2), 9.35; chlorogenic acid, 9.02; epicatechin, 8.65; phloretin glycosides, 5.59; vitamin C, 12.80. A highly linear relationship (r (2) > 0.97) was attained between concentrations and total antioxidant capacity of phenolics and vitamin C. Relative VCEAC values of these compounds were in the order quercetin (3.06) > epicatechin (2.67) > procyanidin B(2) (2.36) > phloretin (1.63) > vitamin C (1.00) > chlorogenic acid (0.97). Therefore, the estimated contribution of major phenolics and vitamin C to the total antioxidant capacity of 100 g of fresh apples is as follows: quercetin (40.39 VCEAC) > epicatechin (23.10) > procyanidin B(2) (22.07) > vitamin C (12.80) > phloretin (9.11) > chlorogenic acid (8.75). These results indicate that flavonoids such as quercetin, epicatechin, and procyanidin B(2) rather than vitamin C contribute significantly to the total antioxidant activity of apples.

Topics: Antioxidants; Ascorbic Acid; Benzothiazoles; Biflavonoids; Catechin; Flavonoids; Free Radicals; Fruit; Malus; Phenols; Proanthocyanidins; Quercetin; Sulfonic Acids

In breast cancer, in situ estrogen production has been demonstrated to play a major role in promoting tumor growth. Aromatase is the enzyme responsible for the conversion of androgen substrates into estrogens. This enzyme is highly expressed in breast cancer tissue compared with normal breast tissue. A wine extract fraction was recently isolated from red wine that exhibited a potent inhibitory action on aromatase activity. Using UV absorbance analysis, high-performance liquid chromatography profiling, accurate mass-mass spectrometry, and nanospray tandem mass spectrometry, most of the compounds in our red wine fraction were identified as procyanidin B dimers that were shown to be aromatase inhibitors. These chemicals have been found in high levels in grape seeds. Inhibition kinetic analysis on the most potent procyanidin B dimer has revealed that it competes with the binding of the androgen substrate with a K(i) value of 6 micro M. Because mutations at Asp-309, Ser-378, and His-480 of aromatase significantly affected the binding of the procyanidin B dimer, these active site residues are thought to be important residues that interact with this phytochemical. The in vivo efficacy of procyanidin B dimers was evaluated in an aromatase-transfected MCF-7 breast cancer xenograft model. The procyanidin B dimers were able to reduce androgen-dependent tumor growth, indicating that these chemicals suppress in situ estrogen formation. These in vitro and in vivo studies demonstrated that procyanidin B dimers in red wine and grape seeds could be used as chemopreventive agents against breast cancer by suppressing in situ estrogen biosynthesis.

Topics: Animals; Anticarcinogenic Agents; Aromatase; Aromatase Inhibitors; Biflavonoids; Catechin; Chromatography, High Pressure Liquid; Dimerization; Enzyme Inhibitors; Estrogen Antagonists; Estrogens; Female; Kinetics; Mass Spectrometry; Mice; Mice, Inbred BALB C; Mice, Nude; Mutagenesis, Site-Directed; Proanthocyanidins; Seeds; Vitis; Wine

The methanol extract of heartwood of Cercidiphyllum japonicum (Cercidiphyllaceae) stimulated proliferation of mouse hair epithelial cells, similar to minoxidil and procyanidin B-2. (+)-Taxifolin ( 2), quercetin ( 3), myricetin ( 4), (+)-dihydromyricetin ( 5) and gallic acid ( 6) were isolated from C. japonicum and showed significant proliferative activities on the hair epithelial cells.

Topics: Animals; Biflavonoids; Catechin; Cell Differentiation; Dose-Response Relationship, Drug; Epithelial Cells; Flavonoids; Hair; Mice; Minoxidil; Phenols; Phytotherapy; Plant Extracts; Polymers; Proanthocyanidins; Saxifragaceae; Thymidine

With the aim of identifying natural products, which possess hair-growing activity, we examined more than 1000 plant extracts with respect to their growth-promoting effects on hair epithelial cells. We discovered intensive growth-promoting activity, about 140% relative to controls, in barley extract. Our strategy for identifying active compounds in barley extract involved subjecting it to column chromatography using HP-20 resin columns, an LH-20 resin column, and preparative high-performance liquid chromatography (HPLC) using an ODS column. The 60% (v/v) aqueous methanol eluted fraction from the HP-20 column and the 75% (v/v) aqueous methanol eluted fraction from the subsequent LH-20 column showed high hair-growing activity in vivo. We isolated two major substances from the LH-20 active fraction using preparative HPLC. By means of mass spectrometry, 1H-NMR, and 13C-NMR analyses, one substance was revealed to be procyanidin B-3 and the other substance was identified as (+)-catechin. Purified procyanidin B-3 showed high hair-growing activity in the form of in vitro hair epithelial cell growth-promoting activity and in vivo anagen-inducing activity; however (+)-catechin showed no hair-growing activity. For the purpose of examining the hair-growing mechanisms of procyanidin B-3, we examined its relationship to the TGF-beta signal pathway, which is known to be a regulator of catagen induction. Addition of TGF-beta1 to hair epithelial cell cultures dose-dependently decreased the cell growth, and addition of procyanidin B-3 to the culture neutralized the growth-inhibiting effect of TGF-beta1. From these results, it is concluded that procyanidin B-3 can directly promote hair epithelial cell growth in vitro, has the potential to counteract the growth-inhibiting effect caused by TGF-beta1 in vitro, and has potential to stimulate anagen induction in vivo.

Topics: Animals; Biflavonoids; Catechin; Cell Division; Cells, Cultured; Chromatography, High Pressure Liquid; Dose-Response Relationship, Drug; Epidermal Cells; Hair; Hordeum; Mice; Mice, Inbred C3H; Plant Extracts; Proanthocyanidins; Transforming Growth Factor beta; Transforming Growth Factor beta1

We have previously reported that several selective protein kinase C (PKC) inhibitors, including procyanidin B-2, promote hair epithelial cell growth and stimulate anagen induction.. We discuss the hypothesis that the hair-growing activity of procyanidin B-2 is related to its downregulation or inhibition of translocation of PKC isozymes in hair epithelial cells.. We examined the effect of procyanidin B-2 on the expression of PKC isozymes in cultured murine hair epithelial cells as well as PKC isozyme localization in murine dorsal skin at different stages in the hair cycle.. We observed that procyanidin B-2 reduces the expression of PKC-alpha, -betaI, -betaII and -eta in cultured murine hair epithelial cells and also inhibits the translocation of these isozymes to the particulate fraction of hair epithelial cells. Our immunohistochemical analyses demonstrated that PKC-alpha, -betaI, -betaII and -eta are specifically expressed in the outer root sheaths of both anagen and telogen hair follicles. The hair matrix at the anagen stage showed no positive staining for these PKC isozymes. Moderate to intense staining for PKC-betaI and -betaII in the epidermis and hair follicles was observed in a telogen-specific manner; however, expression of PKC-alpha and -eta during the telogen stage was not conspicuous. Gö 6976, an inhibitor of calcium-dependent (conventional) PKC, proved to promote hair epithelial cell growth.. These results suggest that PKC isozymes, especially PKC-betaI and -betaII, play an important role in hair cycle progression and that the hair-growing mechanisms of procyanidin B-2 are at least partially related to its downregulation of PKC isozymes or its inhibition of translocation of PKC isozymes to the particulate fraction of hair epithelial cells.

Topics: Animals; Biflavonoids; Catechin; Cells, Cultured; Down-Regulation; Drug Evaluation, Preclinical; Epithelial Cells; Hair; Isoenzymes; Mice; Proanthocyanidins; Protein Kinase C; Skin

In a search for possible antitumor agents from natural sources, megastigmane glycosides and polyphenolic constituents isolated from the leaves of Eriobotrya japonica (Rosaceae) were found to inhibit the 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced activation of Epstein-Barr virus early antigen in Raji cells. Roseoside and procyanidin B-2 were among the active compounds found in an in vitro assay; these compounds were further assessed for antitumor activity in vivo in a two-stage carcinogenesis assay on mouse skin. Roseoside significantly delayed carcinogenesis induced by peroxynitrite (initiator) and TPA (promoter), and its potency was comparable to that of a green tea polyphenol, (-)-epigallocatechin 3-O-gallate, in the same assay.

Topics: 9,10-Dimethyl-1,2-benzanthracene; Animals; Antigens, Viral; Antineoplastic Agents; Biflavonoids; Carcinogens; Catechin; Female; Glucosides; Herpesvirus 4, Human; Humans; Mice; Mice, Inbred ICR; Nasopharyngeal Neoplasms; Norisoprenoids; Peroxynitrous Acid; Plant Leaves; Proanthocyanidins; Rosaceae; Skin Neoplasms; Tea; Tetradecanoylphorbol Acetate; Virus Activation

We isolated the phenolic compounds epicatechin, catechin, procyanidin B-1, procyanidin B-2, hyperin and caffeic acid from the hooks and stems of Uncaria sinensis (HSUS), and studied their protective effects against glutamate-induced neuronal death in cultured rat cerebellar granule cells. Cell viability evaluated by MTT assay was significantly increased by application of epicatechin (100-300 microM), catechin (300 microM), procyanidin B-1 (30-300 microM) and procyanidin B-2 (100-300 microM) compared with exposure to glutamate only. 45Ca2+ influx into cells induced by glutamate was also significantly inhibited by administration ofepicatechin (300 microM), catechin (300 microM), procyanidin B-1 (100-300 microM) and procyanidin B-2 (100-300 microM). These results suggest that epicatechin, catechin, procyanidin B-1 and procyanidin B-2 are the active components of HSUS that protect against glutamate-induced neuronal death in cultured cerebellar granule cells by inhibition of Ca2+ influx.

Topics: Animals; Biflavonoids; Caffeic Acids; Calcium; Catechin; Cell Survival; Cells, Cultured; Cerebellum; Dose-Response Relationship, Drug; Glutamic Acid; Molecular Structure; Neurons; Phenols; Plant Extracts; Plant Stems; Plants, Medicinal; Proanthocyanidins; Quercetin; Rats; Rats, Wistar; Rubiaceae

We have previously reported that proanthocyanidins extracted from grape seeds possess growth-promoting activity toward murine hair epithelial cells in vitro and stimulate anagen induction in hair cycle progression in vivo. This report constitutes a comparison of the growth-promoting activity of procyanidin oligomers and the target cells of procyanidins in the skin. Results show that procyanidin dimer and trimer exhibit higher growth-promoting activity than the monomer. The maximum growth-promoting activity for hair epithelial cells with procyanidin B-2, an epicatechin dimer, reached about 300% (30 microM) relative to controls (= 100%) in a 5 d culture. Optimum concentration of procyanidin C-1, an epicatechin trimer, was lower than that of procyanidin B-2; the maximum growth-promoting activity of procyanidin C-1 was about 220% (3 microM). No other flavonoid compounds examined exhibit higher proliferative activities than the procyanidins. In skin constituent cells, only epithelial cells such as hair keratinocytes or epidermal keratinocytes respond to procyanidin oligomers. Topical application of 1% procyanidin oligomers on shaven C3H mice in the telogen phase led to significant hair regeneration [procyanidin B-2, 69.6% +/- 21.8% (mean +/- SD); procyanidin B-3, 80.9% +/- 13.0%; procyanidin C-1, 78.3% +/- 7.6%] on the basis of the shaven area; application of vehicle only led to regeneration of 41.7% (SD = 16.3%). In this paper, we demonstrate the hair-growing activity of procyanidin oligomers both in vitro and in vivo, and their potential for use as agents to induce hair growth.

Topics: Animals; Biflavonoids; Catechin; Cell Division; Cells, Cultured; Dimerization; Epithelial Cells; Hair; Hair Follicle; Keratinocytes; Mice; Mice, Inbred C3H; Proanthocyanidins

Procyanidin B-2 [epicatechin-(4beta --> 8)-epicatechin] is one of condensed tannin that exists widely in plants. We have reported previously that procyanidin B-2 possesses hair epithelial cell growth-promoting activity and stimulates anagen induction in hair cycle progression. To evaluate the safety of topical procyanidin B-2 as a hair growing agent, we examined the mutagenicity, acute subcutaneous injection, primary irritation, skin sensitization, and eye irritation of this compound. Mutagenicity tests using bacteria showed procyanidin B-2 to be non-mutagenic. Chromosomal aberration tests using CHL cells indicated that procyanidin B-2 caused polyploidy but no structural aberrations. In micronucleus tests for mutagenicity using mice, procyanidin B-2 was negative. Acute subcutaneous injection study using rats revealed no symptoms of significant injury. The lethal dose of procyanidin B-2 is greater than 2000 mg/kg (subcutaneous injection). Primary irritation tests using rabbits indicated that procyanidin B-2 containing preparation shows no primary irritation. In the guinea pig maximization test, there was no evidence of sensitization to procyanidin B-2. In primary ocular irritation tests using rabbits, procyanidin B-2 containing preparation and vehicle showed slight irritation of conjunctivae which is assumed to be caused by ethanol. It is suggested that topical procyanidin B-2 is safe and acceptable from the series of toxicological tests.

Topics: Administration, Topical; Animals; Biflavonoids; Catechin; Female; Hair; Hair Preparations; Injections, Subcutaneous; Irritants; Male; Mice; Mutagenicity Tests; Proanthocyanidins; Rabbits; Rats; Toxicity Tests

To study the tannins from Tripterygium hypoglaucum.. Compounds were isolated by column chromatography and elucidated on the basis of spectroscopic analysis and comparison of references.. The compounds obtained were determined as (+)catechin, (-)epigallocatechin, procyanidin B-3, procyanidin B-4 and gallocatechin-(4 alpha-->8) epicatechin.. All the compounds were obtained from this plant for the first time.

Topics: Biflavonoids; Catechin; Molecular Structure; Plants, Medicinal; Proanthocyanidins; Tannins; Tripterygium

Three active principles were isolated from the leaf of Melastoma candidum using the screening of hypotensive effects on spontaneously hypertensive rats (SHR). Intravenous injection of castalagin, procyanidin B-2, or helichrysoside into SHR lowered the mean blood pressure in a dose-dependent manner, with helichrysoside being the most potent compound. Plasma noradrenaline (NA) levels, both basal in SHR and elevated in normal rats through cold-stress stimulation, were attenuated by these compounds in a way which was not influenced by adrenalectomy. Decrease of NA release from sympathetic nerves was assumed to be responsible. Moreover, the hypertensive effect of various vasoconstrictors in anesthetized rats was reduced by helichrysoside. The same results were also observed in castalagin or procyanidin B-2 treated animals. The results indicate that the three principles possess the ability to lower blood pressure through a decrease of sympathetic tone as well as due to direct vasodilatation in SHRs.

Topics: Animals; Antihypertensive Agents; Biflavonoids; Biphenyl Compounds; Catechin; Catechols; Chromones; Drugs, Chinese Herbal; Hydrolyzable Tannins; Molecular Structure; Norepinephrine; Proanthocyanidins; Rats; Rats, Inbred SHR; Rats, Inbred WKY

Procyanidin B-5 (1), epicatechin-(4 beta----8)-epicatechin-(4 beta----6)-epicatechin (2), and epicatechin-(4 beta----6)-epicatechin-(4 beta----8)-epicatechin-(4 beta----6)-epicatechin (3), which showed an inhibitory effect toward protein kinase C, were isolated from the rhizomes of Davallia mariesii Moore. Detailed analyses of their 1H- and 13C-nuclear magnetic resonance spectra were carried out by the use of two-dimensional nuclear magnetic resonance techniques.

Topics: Biflavonoids; Carbohydrate Sequence; Carbon Isotopes; Catechin; Magnetic Resonance Spectroscopy; Medicine, Chinese Traditional; Molecular Sequence Data; Plants, Medicinal; Proanthocyanidins; Spectrum Analysis

The effects of procyanidins on platelet aggregation and arachidonate metabolism in platelets were studied. Nine procyanidins were used in this investigation. Procyanidins B-2-S, EEC and C-1 significantly induced the inhibition of platelet aggregation, and the potency of inhibition was comparable with aspirin. Procyanidin B-2-S was used as a representative of procyanidins for further studies on the effect on arachidonate metabolism. In arachidonate metabolism by fatty acid cyclooxygenase pathway, B-2-S inhibited TXB2 and HHT formation by intact platelets treated with exogenous arachidonic acid. It also inhibited TXB2 formation measured by a specific radioimmunoassay when the cells were challenged with calcium ionophore A23187. In cell-free system, B-2-S inhibited both TXB2 and 12-HETE bioxynthesis in platelet microsome and cytosol, respectively. The inhibitory effect on thromboxane biosynthesis might explain the inhibitory effect of procyanidins on platelet aggregation.

Topics: Animals; Arachidonate 12-Lipoxygenase; Arachidonic Acid; Arachidonic Acids; Biflavonoids; Biotransformation; Blood Platelets; Blood Proteins; Catechin; Cell-Free System; Cytosol; In Vitro Techniques; Male; Microsomes; Platelet Aggregation; Platelet Aggregation Inhibitors; Proanthocyanidins; Rabbits; Radioimmunoassay; Serum Albumin, Bovine