Immature Rubus coreanus Shows a Free Radical-Scavenging Effect and Inhibits Cholesterol Synthesis and Secretion in Liver Cells

Rubus coreanus fruits have been employed as a traditional medicine for centuries in the Asia-Pacific region. Its pharmacological action differs according to the different extraction methods utilized and the degree of fruit ripening. In this study, we determined the cellular effect of different ethanol extracts of mature and immature Rubus coreanus fruits in human hepatic cell line, HepG2 cells. The antioxidant activity, effect on superoxide dismutase activity and cholesterol biosynthesis efficiency was also evaluated. Immature Rubus coreanus extract showed higher antioxidant capability, compared with that of its mature fractions. Cellular antioxidant proteins including HO-1, Cu/Zn-superoxide dismutase and catalase were highly expressed in the presence of Rubus coreanus. Cholesterol levels in HepG2 cells treated with the water fraction of immature Rubus coreanus were significantly reduced. This antihyperlipidaemic action of Rubus coreanus is a consequence of cholesterol biosynthesis and extracellular secretion in HepG2 cells. These results indicate that among different ethanol fraction of mature and immature Rubus coreanus fruit extracts, water extract of immature fruit extract shows higher antioxidant as well as higher antihyperlipidaemic action.     

Effects of prostaglandin E1 on acid secretion, mucosal histamine content and histidine decarboxylase activity in rat stomach

1. Prostaglandin E(1) inhibits basal and pentagastrin-stimulated gastric acid secretion. The mechanism of this action is not clear. One possible explanation might be that prostaglandin E(1) interferes with the local release or synthesis of histamine which has been proposed as the mediator of the effects of gastrin on the parietal cell.2. A single injection of prostaglandin E(1) did not affect mucosal histamine content or histidine decarboxylase activity in the rat stomach. Pentagastrin lowered the histamine content and activated the histidine decarboxylase to the same extent in prostaglandin E(1)-pretreated and in control rats. We conclude therefore that the inhibitory effect of prostaglandin E(1) on basal and pentagastrin-stimulated acid secretion is not caused by inhibition of histamine release or histamine synthesis.3. Repeated injections of prostaglandin E(1) resulted in a significant elevation of the gastric histidine decarboxylase activity in normal but not in antrectomized rats. Conceivably, this increase in enzyme activity is secondary to prostaglandin E(1)-induced inhibition of acid secretion, which will stimulate release of gastrin due to the rise in intragastric pH.     

Inhibition of cyclooxygenase and prostaglandin E2 synthesis by gamma-mangostin, a xanthone derivative in mangosteen, in C6 rat glioma cells.

The fruit hull of mangosteen, Garcinia mangostana L., has been used for many years as a medicine for treatment of skin infection, wounds, and diarrhea in Southeast Asia. In the present study, we examined the effect of gamma-mangostin, a tetraoxygenated diprenylated xanthone contained in mangosteen, on arachidonic acid (AA) cascade in C6 rat glioma cells. gamma-Mangostin had a potent inhibitory activity of prostaglandin E2 (PGE2) release induced by A23187, a Ca2+ ionophore. The inhibition was concentration-dependent, with the IC50 value of about 5 microM. gamma-Mangostin had no inhibitory effect on A23187-induced phosphorylation of p42/p44 extracellular signal regulated kinase/mitogen-activated protein kinase or on the liberation of [14C]-AA from the cells labeled with [14C]-AA. However, gamma-mangostin concentration-dependently inhibited the conversion of AA to PGE2 in microsomal preparations, showing its possible inhibition of cyclooxygenase (COX). In enzyme assay in vitro, gamma-mangostin inhibited the activities of both constitutive COX (COX-1) and inducible COX (COX-2) in a concentration-dependent manner, with the IC50 values of about 0.8 and 2 microM, respectively. Lineweaver-Burk plot analysis indicated that gamma-mangostin competitively inhibited the activities of both COX-1 and -2. This study is a first demonstration that gamma-mangostin, a xanthone derivative, directly inhibits COX activity.     

Inhibitory action of tranilast, an anti-allergic drug, on the release of cytokines and PGE2 from human monocytes-macrophages.

Tranilast, an anti-allergic drug that inhibits the release of substances such as histamine and prostaglandins from mast cells, has been reported to improve keloids and hypertrophic scars which originate from the abnormal proliferation and excessive collagen accumulation of fibroblasts. It has been considered that various chemical mediators produced by inflammatory cells play important roles in the development of keloids and hypertrophic scars. We therefore studied the effect of tranilast on the release of chemical mediators including transforming growth factor (TGF)-beta 1, interleukin (IL)-1 beta and prostaglandin (PG) E2 which are produced by the human monocytes-macrophages, and estimated whether these mediators induce collagen synthesis and cell proliferation of normal skin fibroblasts. Tranilast inhibited the release of TGF-beta 1, IL-1 beta and PGE2 from the human monocytes-macrophages. TGF-beta 1 (25-200 pM) enhanced the collagen synthesis by fibroblasts. IL-1 (0.1-1 U/ml) increased the proliferation and conversely decreased the collagen synthesis. PGE2 (2 micrograms/ml) enhanced the collagen synthesis. These results suggest that tranilast suppresses collagen synthesis by fibroblasts through inhibiting TGF-beta 1 and PGE2 production and cell proliferation by fibroblasts through inhibiting IL-1 production by inflammatory cells such as macrophages.     

Magnolol and honokiol account for the anti-spasmodic effect of Magnolia officinalis in isolated guinea pig ileum

Magnolia officinalis is a commonly used traditional Chinese medicine for treating gastrointestinal disorders. HPLC quantification analysis revealed that magnolol and honokiol were the most abundant constituents of M. officinalis extracts, with their contents in the ethanol extract being the highest, the water extract the least and the 50 % ethanol extract in between. In guinea pig isolated ileum, both magnolol and honokiol inhibited contraction to acetylcholine. The herbal extracts also produced inhibitory responses, in an order of decreasing efficacy: ethanol extract > 50 % ethanol extract > water extract. The differences in inhibitory efficacies among the three extracts were similar to the differences in their magnolol and honokiol contents. Further examination demonstrated that two mixtures containing solely magnolol and honokiol at concentrations identical to those determined in the ethanol and water extracts exhibited similar levels of anti-spasmodic effects as their respective extracts while a "blank" ethanol extract free of magnolol and honokiol failed to produce any response. These observations suggest that the magnolol and honokiol contents account for the anti-spasmodic effects of M. officinalis extracts in guinea pig isolated ileum.     

Crude extracts of Agaricus brasiliensis induce apoptosis in human oral cancer CAL 27 cells through a mitochondria-dependent pathway

In Taiwan, oral cancer is the fourth leading cause of male cancer mortality, and is still increasing. The Basiodiomycete, Agaricus brasiliensis Murill (ABM) is a dietary mushroom and has been known for its immuneenhancing, antitumor, antioxidation, antiviral and antimutagenesis functions. However, the exact anticancer mechanisms of ABM on human oral cancer cells are still unclear. In the present study, we investigated the effects of 50% ethanol crude extracts and hot water extracts of ABM on oral cancer CAL 27 cells. We observed that 0.9 mg/ml and 0.7 mg/ml of ABM 50% ethanol crude extracts and hot water, respectively, caused morphological changes and significantly reduced cell viability after 48-h treatment. The results showed that both extracts of ABM inhibited cell proliferation, increased the Ca(2+) release, reduced the mitochondria membrane potential (ΔΨm), and caused cell cycle arrest in the G(0)/G(1) phase, which contributed to apoptosis. Additionally, ABM induced DNA fragmentation, a characteristic of apoptosis and the expressions of apoptosis-related proteins, including apoptosis-inducing factor, cytochrome c, and caspase-3, were increased. Overall, we demonstrated that 50% ethanol crude extract and hot water extracts of ABM were able to induce apoptotic cell death in CAL 27 cells via the release of cytochrome c from mitochondria into the cytoplasm and activation of caspase-3 in vitro.     

Rubus croceacanthus Leveille inhibits mast cell-mediated anaphylactic-like reaction and tumor necrosis factor-alpha secretion

This work aims at examining the effect of the concentrated methanol extract of Rubus croceacanthus Leveille (RCL) on mast cell-mediated anaphylactic-like reaction in a murine model. RCL inhibited compound 48/80-induced systemic anaphylactic-like reaction. When RCL was given as pre-treatment at concentrations ranging from 0.01 to 1 mg/ml, the histamine release from rat peritoneal mast cells induced by compound 48/80 or anti-dinitrophenyl (DNP) immunoglobulin E (IgE) was reduced in a dose-dependent manner. RCL also inhibited passive cutaneous anaphylaxis activated by anti-DNP IgE. In addition, RCL inhibited phorbol 12-myristate 13-acetate and A23187-induced tumor necrosis factor-alpha secretion from human mast cell line HMC-1 cells. These results indicate that RCL may possess a strong anti-anaphylactic activity.     

Effects of hop extracts on nasal rubbing and sneezing in BALB/c mice

The effects of hop extracts (Humulus lupulus L.) on histamine release from rat peritoneal mast cells and human basophilic KU812 cells were studied. Hop water extract (HWE) and XAD-4 50% methanol fraction of HWE (MFH) inhibited histamine release from rat mast cells induced by compound 48/80 at concentrations of 100 and 10 mug/ml, respectively. Almost the same findings were observed with A23187-induced histamine release from KU812 cells. Next, we studied the effects of hop extracts on antigen-induced nasal rubbing and sneezing in sensitized BALB/c mice. HWE caused a significant inhibition of nasal rubbing and sneezing at a dose of 500 mg/kg. MFH also inhibited nasal rubbing and sneezing dose-dependently. A significant difference was observed from 100 mg/kg in nasal rubbing and 200 mg/kg in sneezing. The effects of both extracts became clear after repeated administration. HWE and MFH significantly inhibited both nasal rubbing and sneezing, respectively, after consecutive treatment for 15 d at smaller doses compared with single administration. This finding indicates that the active component of hop is included in MFH, which was absorbed to Amberlite XAD-4 and eluted with 50% methanol. These results clearly demonstrated that hop extracts may be effective in the relief of symptoms of allergic rhinitis.     

蜂斗菜不同提取物对豚鼠离体回肠收缩的影响

目的 比较蜂斗菜不同提取物对豚鼠离体回肠收缩的影响。方法 采用豚鼠离体回肠实验,以组胺、乙酰胆碱不同激动剂为研究模型,比较蜂斗菜CO₂超临界提取物、80%乙醇提取物、80%乙醇提取物的不同极性提取物及乙酸乙酯提取物经硅胶柱层析分离获得的不同馏分对豚鼠离体回肠的收缩作用,计算各个提取物对豚鼠回肠收缩幅度的抑制率。结果 蜂斗菜不同提取物对组胺、乙酰胆碱所致的豚鼠离体回肠收缩有显著拮抗作用,其中乙酸乙酯提取物硅胶柱色谱的馏分抑制作用最强。结论 蜂斗菜不同提取物均能抑制组胺、乙酰胆碱引起的豚鼠离体回肠收缩作用,脂溶性成分抑制作用最强,其机制可能与M、H₁受体的抑制有关。     

Inhibitory effects of Moutan cortex on immediate allergic reactions

The anti-allergic effect of an ethanol extract from Moutan Cortex was evaluated in some animal models. The Moutan Cortex extract (30, 100 mg/kg, i.p.) dose-dependently inhibited systemic anaphylactic shock induced by compound 48/80 in mice. It also inhibited dose-dependently the scratching behavior induced by compound 48/80 or histamine at a dose of 100 mg/kg. An increase in the vascular permeability induced by compound 48/80 or histamine was also inhibited by the Moutan Cortex. In addition, in vitro studies, the Moutan Cortex inhibited histamine release from rat peritoneal mast cells induced by compound 48/80. To investigate the active component of Moutan Cortex extract, it was suspended in water and extracted with EtOAc to yield EtOAc insoluble (A) and soluble (B) fractions. The effect of extract (B) was more potent than that of extract (A) in inhibiting histamine release. From these findings, it seems likely that the Moutan Cortex extract is effective in antagonizing certain pharmacological effects induced by compound 48/80, which is probably mediated by inhibiting the release of histamine from mast cells and antagonizing the effect on histamine. The main active component of Moutan Cortex is considered to be contained in extract (B). In conclusion, Moutan Cortex may be useful for the relief of symptoms of atopic dermatitis and other allergy-related diseases.     

Effect of tenoxicam and indomethacin on the release of histamine, prostaglandin E2 and leukotrienes from various cells

Tenoxicam and indomethacin were studied with regard to their effects to modulate mediator release (histamine, prostaglandin E2 (PGE2) mono-hydroxyeicosatetraenoic acids, leukotrienes) from various cells. For histamine release human lymphocytes, monocytes, and basophils were analyzed with either anti-IgE or the calcium ionophore A 23187. Rat mast cells were stimulated with the calcium ionophore A 23187. With tenoxicam significant inhibition of histamine release was obtained as compared to the effects of indomethacin. Enhancement of histamine release at defined concentrations was more often observed with indomethacin than with tenoxicam. At high concentrations of indomethacin the formation of the radiolabelled phospholipids and 5S-hydroxy-6-trans-8,11,14-cis-eicosatetraenoic acid (14C-arachidonic acid metabolites) from stimulated human polymorphonuclear neutrophilic leukocytes was inhibited. With regard to endogenous leukotriene and PGE2 release tenoxicam inhibited leukotrienes B4 and C4 and PGE2 release. Tenoxicam appeared to be more active than indomethacin.     

Anti-inflammatory effect of germanium-concentrated yeast against paw oedema is related to the inhibition of arachidonic acid release and prostaglandin E production in RBL 2H3 cells

1 To investigate anti-inflammatory activity of organic germanium, we measured the effect of germanium-concentrated yeast on arachidonic acid release, prostaglandin E(2) (PGE(2)) production, histamine release, and intracellular H(2)O(2) or hydroperoxide generation in RBL 2H3 cells, and carrageenan-induced paw oedema in rats. 2 Germanium-concentrated yeast dose-dependently inhibited carrageenan-induced paw oedema, suggesting that germanium-concentrated yeast has anti-inflammatory activity in acute inflammation. 3 Germanium-concentrated yeast significantly inhibited melittin-induced arachidonic acid release and PGE(2) production in RBL 2H3 cells. 4 Germanium-concentrated yeast did not affect melittin-induced histamine release and silica-induced intracellular H(2)O(2) or hydroperoxide generation in RBL 2H3 cells. 5 These results suggest that anti-inflammatory activity of germanium-concentrated yeast appears partly to be related to the inhibition of arachidonic acid release and PGE(2) production in RBL 2H3 cells.     

The effect of acteoside on histamine release and arachidonic acid release in RBL-2H3 mast cells

The effect of acteoside, a phenylpropanoid glycoside isolated from Clerodendron trichotomum Thunberg, on histamine and arachidonic acid release was investigated in RBL 2H3 cells. Histamine was dose-dependently released from RBL 2H3 cells by melittin, arachidonic acid and thapsigargin. In extracellular Ca2+-free solution, basal secretion of histamine increased by two fold. The response of histamine release to melittin and thapsigargin in Ca2+-free solution was significantly decreased, whereas the response to arachidonic acid was significantly increased as compared with those in normal solution. Acteoside inhibited histamine release induced by melittin, arachidonic acid and thapsigargin in a dose-dependent manner in the presence or absence of extracellular Ca2+. However, the inhibitory activity of acteoside was more potent in normal solution than that in Ca2+-free solution. These data suggest that inhibitory mechanism of acteoside on histamine release may be related to extracellular Ca2+. On the other hand, acteoside significantly inhibited arachidonic acid release and prostaglandin E2 production induced by 0.5 microM melittin. It is possible that acteoside may be developed as an anti-inflammatory agent.     

Echinacea alkylamides inhibit interleukin-2 production by Jurkat T cells

Alkylamides present in Echinacea species have reported immunomodulatory actions, yet their direct effects on T lymphocytes, key mediators of antiviral immunity, are poorly understood. We hypothesized that constituents present in ethanolic extracts of Echinacea species exert direct immunomodulatory effects on human Jurkat T cells. Modulation of IL-2 production by submaximally stimulated Jurkat cells was determined in response to treatment with extracts prepared from dried aerial parts of Echinacea purpurea. Cells were treated with the extracts, with alkylamides or caffeic acid derivatives isolated from Echinacea species, or with corresponding ethanol vehicle, in the absence or presence of phytohemagglutinin and phorbal ester. E. purpurea extracted in a solvent mixture of 95:5 ethanol/water dose-dependently inhibited IL-2 production. This IL-2 inhibitory activity correlated with the presence of alkylamides but not caffeic acid derivatives, as determined by high performance liquid chromatography/electrospray ionization-mass spectrometry analysis. Simultaneous measurement of secreted IL-2 by ELISA and cell viability by the XTT assay showed that the 95:5 ethanol/water extract of E. purpurea was both IL-2 suppressive and cytotoxic at 50 and 100 microg/mL. Lower concentrations from 6.25 to 25 microg/mL significantly decreased IL-2 production but not cell viability. Alkylamides at concentrations found in a 50 microg/mL extract decreased IL-2 production by approximately 50%. Two Echinacea-derived alkylamides significantly depressed IL-2 production but not cell viability in a dose-dependent manner. Thus, alkylamides present in E. purpurea suppress the ability of activated Jurkat T cells to produce IL-2 independently of direct, cytotoxic effects.     

Characterization of the effect of Epilobium extracts on human cell proliferation

We have previously shown that extracts of different Epilobium species, a phytotherapeutic agent used in folk medicine as a treatment for benign prostatic hyperplasia, inhibit proliferation of human prostate cells. The selectivity of this effect was evaluated in four different human cell lines (PZ-HPV-7, normal prostate cells; LNCaP, transformed prostate cells; HMEC, mammary cells, and 1321N1, astrocytoma cells). Different extracts of Epilobium species (E. rosmarinifolium, E. spicatum, and E. tetragonum) had similar growth-inhibitory effects in all cell lines tested, indicating a lack of specificity for prostate cells. Inhibition of DNA synthesis was mostly due to the nonpolar fraction of the extracts which is expected to contain flavonoids and sterols. Polar fractions were devoid of activity with the exception of that from E. rosmarinifolium. This species is the most potent in the antiproliferative effect and contains the highest concentration of oenothein B, a hydrolyzable ellagitannin. Oenothein B inhibited DNA synthesis in all four cell lines tested. Extracts of E. angustifolium (the Linné denomination of E. spicatum) and of E. spicatum from different sources were compared for their ability to inhibit DNA synthesis and for their oenothein B content. The E. angustifolium extract contained an amount of oenothein B 40-fold higher than the other extract of the same species and was ten times more potent in inhibiting DNA synthesis in a human prostate cell line. These results indicate that Epilobium extracts inhibit proliferation of prostate cells in a nonspecific manner. Oenothein B may play a role in this effect, but other active compounds are also present. The difference observed between extracts from the same species underscores the importance of determination and standardization of active ingredients in phytotherapeutic agents.     

无梗五加果实提取物对大鼠CYP450活性的影响

目的研究无梗五加果实提取物对大鼠CYP450亚型CYP1A2、CYP2C19、CYP2E1、CYP3A4活性的影响。方法以咖啡因、奥美拉唑、氯唑沙宗和咪达唑仑作为CYP1A2、CYP2C19、CYP2E1和CYP3A4特异性探针药物,配制cocktail混合探针溶液,建立同时测定4种探针药物血药浓度的高效液相色谱法。将SD大鼠随机分为无梗五加果实70%乙醇提取物组、水提取物组和对照组,每天分别ig无梗五加果实70%乙醇提取物溶液、水提取物溶液和溶剂10 mL/kg,连续给药1周,于第8天ip混合探针药物10 mL/kg,分别在给药0、0.083、0.25、0.417、0.583、0.833、1、2、3、5、8、11、12 h于大鼠眼眶静脉丛采血,采用HPLC法对血浆样品进行分析,对给药组和对照组探针药物的药动学参数生物半衰期(t_(1/2))进行比较。结果与对照组比较,无梗五加果实水提取物组和70%乙醇提取物组咖啡因、咪达唑仑的t_(1/2)显著降低,奥美拉唑、氯唑沙宗的t_(1/2)显著增加,差异均具有统计学意义(P0.05、0.01)。结论无梗五加果实70%乙醇提取物和水提取物对大鼠的CYP2C19、CYP2E1有抑制作用,对大鼠的CYP1A2、CYP3A4有诱导作用。     

Indomethacin-induced alterations in corticosteroid and prostaglandin release by isolated adrenocortical cells of the cat.

1 The effects of purported prostaglandin synthesis inhibitors on steroid and prostaglandin (E and F) release from trypsin-dispersed cat adrenocortical cells were investigated. 2 Low indomethacin concentrations potentiated adrenocorticotrophin (ACTH)-evoked prostaglandin and steroid release, whereas higher concentrations depressed both responses to ACTH. The steroidogenic response to exogenous prostaglandin E2 was not markedly altered over a wide range of indomethacin concentrations. 3 Indomethacin enhanced basal steroid release but did not enhance basal prostaglandin E or F release. 4 5,8,11,14-Eicosatetraynoic acid (ETA) elicited a concentration-dependent inhibition of ACTH-induced steroid release, but had little effect on prostaglandin E2-induced steroid release. A high concentration of ETA inhibited prostaglandin E and F release. 5 These data are discussed in relation to the concept that prostaglandins provide a critical link in ACTH-induced corticosteroidogenesis.     

Interleukin-1 potentiates histamine-induced release of prostacyclin from human endothelial cells.

1. In human cultured umbilical vein endothelial cells, interleukin-1 potentiated histamine-induced release of prostacyclin in a time- and concentration-dependent manner. 2. In cells incubated with interleukin-1 for 24 h, maximal potentiation was observed when cells were pre-incubated with 0.5 u ml-1 interleukin-1 before stimulation with histamine (1 microM-1 mM). 3. In cells incubated with 0.5 u ml-1 interleukin-1, 20 min pre-incubation was sufficient to induce a statistically significant potentiation of prostacyclin release induced by 1 microM histamine (P less than 0.05). 4. Nifedipine but not cycloheximide, significantly (P less than 0.05) inhibited histamine-induced release of prostacyclin and interleukin-1 potentiation of histamine-induced release of prostacyclin (P less than 0.05). 5. Incubation with 1 u ml-1 interleukin-1 induced a two fold increase in cellular prostaglandin synthetase activity within 30 min. The enzyme activity increased up to 6 h and was maintained up to 24 h. In cells co-incubated with cycloheximide and 1 u ml-1 interleukin 1, prostaglandin synthetase activity at 24 h was the same as that in unstimulated cells. Prostacyclin release was not significantly inhibited in cells co-incubated with cycloheximide and interleukin 1. 6. These results suggest that interleukin-1 potentiates histamine-induced release of prostacyclin by rapid up-regulation of prostaglandin synthetase activity as well as by inducing synthesis of enzyme protein. These mechanisms may act to potentiate/regulate vascular endothelial responses in inflammatory reactions.     

Effects of the extract of the bark of Magnolia obovata and its biphenolic constituents magnolol and honokiol on histamine release from peritoneal mast cells in rats.

We have previously reported that saiboku-to, an Oriental herbal remedy composed of a mixture of 10 different herbal extracts, possesses anti-histamine release effect on mast cells in rats. This effect may be due mainly to the extract of the bark of Magnolia obovata (M. obovata), a constituent herb of saiboku-to. In the present study, it was demonstrated that the bark extract inhibited compound 48/80 (C48/80)-induced histamine release from mast cells in a concentration-dependent manner (50 % inhibitory concentration, IC(50) = 56.98 microg/ml). Furthermore, the inhibitory activity was found in the methanol fraction, but not in water and 50 % aqueous methanol fractions derived from the bark extract. Magnolol and honokiol isolated from the methanol fraction inhibited C48/80-induced histamine release from mast cells. The potency of magnolol (IC(50) = 1.04 microg/ml) was greater than that of honokiol (IC(50) = 2.77 microg/ml). Furthermore, the actual amount of magnolol (49.76 +/- 1.14 mg) contained in the bark of M. obovata (5 g) was greater than that (8.58 +/- 0.19 mg) of honokiol. Taken together, the present results suggest that magnolol may be responsible for the biological efficacy of the bark extract of M. obovata.