摘要:

AbstractIn this study 13 semi‐synthetic derivatives were prepared from the sesquiterpene lactone eupatoriopicrin, with the aim of obtaining compounds that are more active than eupatoriopicrin, and to give more insight into structure–activity relationships. The compounds were screened for cytotoxicityin vitroagainst the tumour cell lines EAT, P388, FIO 26, L5178Y(s) (murine) and HeLa (human). Cytotoxicity was compared with the germacranolides eupatoriopicrin, 5′‐dehydroxy eupatoriopicrin (‘compound 1’), hiyodorilactone E, eupatolide and eucannabinolide fromEupatorium cannabinumL. and with the eudesmanolides alantolactone and isoalantolactone fromInula heleniumL. Acetalization of both hydroxyl groups in the ester side chain of eupatoriopicrin with acetone enhanced cytotoxicity 2–7‐fold. Introduction of bulky groups, such as alkyl groups with a longer carbon chain and (halogenated) acetophenone derivatives, via acetalization, reversed the enhancement. Oxidation at the germacrane ring structure of eupatoriopicrin acetonide, yielding an alcohol or an epoxy derivative, affected cytotox

ISSN:0951-418X    

DOI:10.1002/ptr.2650020302

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractThe pharmacological effect of the hydroalcoholic extract ofJatropha ellipticawas analysed inin vivoandin vitromodels. When given orally in mice, the extract showed a low acute toxicity (LD505 g/kg). In a dose of 0.5 or 1 g/kg p.o. the extract did not interfere with diuresis in the rat, but was found to be effective in blocking rat paw oedema induced by carrageenan and partially, serotonin‐induced oedema. In the same dose, the extract failed to inhibit rat paw oedema induced by dextran and the increase of rat cutaneous vascular permeability caused byBothrops Jararacavenom, dextran, histamine, PAF‐acether and serotonin. Pre‐incubation of the isolated rat uterus and guinea‐pig ileum with the extract (0.2–0.8 mg/mL), produced a concentration‐related and non‐competitive inhibition of contractions induced by acetylcholine and bradykinin. However, the extract was about 2‐fold more potent in inhibiting the contraction of both agonists in guinea‐pig ileum than in rat uterine muscle. In rat aorta, the extract (50–100 μg/mL) caused a concentration‐dependent inhibition of noradrenaline‐evoked contractions, being about 5‐fold more potent when compared to the IC50val

ISSN:0951-418X    

DOI:10.1002/ptr.2650020303

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractNew Zealand rabbits were divided into three equal groups: (1) controls, (2) animals receiving high‐fat diet (HFD) containing cholesterol and coconut oil, and (3) HFD + Padma 28. A pronounced reduction in lipid metabolism disturbancs and in severity of plaque formation occurred after Padma 28 had been administered. Lipid content in serum, lever homogenate and liver microsomes was depressed. An increase in the microsomal phosphatidylcholine content was observed. The cytochrome P‐450 content in liver microsomes was significantly elevated, and the concentration of malondialdehyde in the blood serum of rabbits was decreased whilst insulin levels were normalized and testosterone content was increased. Atherosclerotic plaque intensity at 12 weeks measured planimetrically averaged 67.3% in HFD‐fed animals but only 15.5% in Padma 28‐treated rabbits. These findings suggest that Padma 28, in addition to lowering serum lipid level in rabbits on an experimental diet also affect metabolic processes in the liver and may modify lipid deposition in major a

ISSN:0951-418X    

DOI:10.1002/ptr.2650020304

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractStudies have been made of eugenol on isolated tissues from man and laboratory animals, and on ratsin vivo. Eugenol inhibited prostaglandin synthesis, and reduced the tone of isolated gut muscle and myometrium. With ratsin vivo, the compound reduced the rate of intestinal transit, the intestinal accumulation of fluid induced by prostaglandin E2, and the diarrhoea induced by castor oil. Eugenol showed anti‐inflammatory activity in the rat paw carrageenin oedema tes

ISSN:0951-418X    

DOI:10.1002/ptr.2650020305

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractRubratoxin B is a substituted higher homolog of byssochlamic acid in which the ethyl group is replaced by a six‐membered ring containing an unsaturated lactone. Hydrogenation of the unsaturated lactone greatly reduces the acute toxixity of the compound. The acute median lethal doses of rubratoxin B and hydrogenated rubratoxin in male mice were 5.6 and 31 mg/kg, respectively. Pretreatment with phenobarbital (60 rag/kg × 4 days) or with SKF 525A (40 mg/kg) failed to significantly alter the toxicity of either compound. Histopathological examination of mice treated with rubratoxin B (3.5 mg/kg) revealed areas of hepatic zonal necrosis and marked necrosis of kidney tubules. No necrosis was observed in mice treated with hydrogenated rubratoxin (20 mg/kg). Hepatic microsomal mixed function oxidase activity was significantly reduced in mice pretreated with rubratoxin B (0.5 mg/kg × 4 days), while pretreatment with hydrogenated rubratoxin (2.5 mg/kg × 4 days) failed to depress microsomal activity. Our studies document the requirement of an alpha, beta unsaturated lactone ring for rubratoxin B toxicity. Based on the results from these studies the mechanism for rubratoxin B induced toxicity is postulated to be due to its electrophilic properties and subsequent alkylating acti

ISSN:0951-418X    

DOI:10.1002/ptr.2650020306

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractUlceroprotective action of several flavonoid compounds isolated fromGenista rumelicaVel. (total flavonoid mixture, luteoline‐7‐glycoside, genistine) was established on five models of gastric ulcer in rats, genistine being the most active. Comparison was made against several standard antiulcer durgs (Succus Liquiritiae, Caved S, Almagel). A combined drug Flavogastrol, containing total flavonoid mixture, Semmen Lini gel and antacid compounds, was prepared and demonstrated ulceroprotective activity and low toxic

ISSN:0951-418X    

DOI:10.1002/ptr.2650020307

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractThe effects of chalcones and flavanones isolated from Sinkiang Licorice (Glycyrrhiza inflataBat.) on leukotriene B4(LTB4) and C4(LTC4) formation in human polymorphonuclear neutrophils (PMNs) were investigated. Licochalcone A (2‐methoxy‐4,4′‐dihydroxy‐5‐α,α‐dimethyl‐allylchalcone) and licochalcone B (2‐methoxy‐3,4,4′‐trihydroxychalcone), at concentrations of 10−3to 10−6M, inhibited calcium ionophore A 23187 (A 23187)‐induced LTB4and LTC4formation in human PMNs. The concentration of licochalcones A required for 50% inhibition (LC50) of LTB4and LTC4formation was 4.6 × 10−7and 4.2×10−6M, respectively, using 2 μM A 23187. The IC50values of licochalcone B for LTB4and LTC4formation were also 1.2 × 10−6and 2.0×10−6M, respectively. In addition, licochalcones A and B significantly increased cyclic AMP level in human PMNs at concentrations of 10−4to 10−3M. Licochalcones A and B were found to reduce the elevation of the cytosolic free calcium concentration induced by calcium ionomycine, dose‐dep

ISSN:0951-418X    

DOI:10.1002/ptr.2650020308

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractVarious fractions ofVerbesina encelioideshave demonstrated significant antibacterial, antifungal, antiviral, antitumor, hypoglycaemic and anti‐implantation activitie

ISSN:0951-418X    

DOI:10.1002/ptr.2650020309

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractA HPLC‐analysis using the photodiode‐array detection technique of the volatile oil of garlic bulbs is presented. Self‐distilled garlic‐oils from six various origins showed similar fingerprint chromatograms with diallyl trisulphide as main compound. Three investigated commercial oils contained significantly higher amounts of diallyl dis

ISSN:0951-418X    

DOI:10.1002/ptr.2650020310

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractThe hypotensive effects of the alcoholic extract ofThymus orospedanuswere investigated in bothin vivoandin vitroassays. Our results indicate that the extract reduced rat blood pressure and modified the dose–response curve to epinephrine in the rat vas deferens and the rabbit artery, indicative of a competitive antagonis

ISSN:0951-418X    

DOI:10.1002/ptr.2650020311

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY