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PubMedDate not supplied

Synchronous analysis method for detection of citrinin and the lactone and acid forms of monacolin K in red mold rice.

The Monascus product known as red mold rice (RMR) has been found to contain the cholesterol-lowering agent monacolin K (MK), including the lactone form (MKL) and the acid form (MKA) and mycotoxin citrinin (CT). In current studies, CT and MK are usually detected by different analysis methods, which have a high level of error, and are inconvenient, expensive, and time-consuming. The goal of this study is to establish a rapid synchronous analysis method for the detection of CT, MKL, and MKA levels in RMR. In this study, CT, MKL, and MKA are extracted by the same extraction method and are then separated in a reversed-phase high-performance liquid chromatography (HPLC) C18 column. The elution from the C18 column is then passed through an ultraviolet detector and introduced directly into the fluorescence detector. The results show that higher recovery rates of CT, MKL, and MLK are yielded from RMR powder by extracting with 95% ethanol (10 mL) at 60 degrees C for 30 min. Regarding the optimal conditions of HPLC, the peaks of CT, MKL, and MKA can be clearly separated from any noise peaks by isocratic elution with optimum mobile phase, acetonitrile-water-trifluoroacetate (55 + 45 + 0.05, v/v).

Acetonitriles↗
PubMed1991

[The contents of gamma-aminobutyric acid and glutamic acid in brain affected by coriaria lactone].

Capillary chromatography was applied to studying the contents of gamma-aminobutyric acid (GABA) and glutamic acid (Glu) in brain affected by coriaria lactone. The results showed that there was a significant increase in the content of Glu whereas no significant change in the content of GABA was noted. The precisions for GABA and Glu were 3.3% and 4.98% and the recoveries of them were 80.5% and 85.2%, respectively. Capillary chromatography is a good method for determining the contents of GABA and Glu in brain, which has the characteristics of rapid and high sensitivity.

Animals↗
PubMed1991

[Observation of enzyme histochemistry and ultrastructure of brain in kindling rats with epilepsy induced by intraperitoneal injection of coriaria lactone].

Kindling model of epilepsy induced by intraperitoneal injection of Coriaria lactone (CL) was used in the experiment. The dose of CL was 1.25 mg/kg. Thirty rats in various periods of kindling were killed and the materials of cerebral cortex, hippocampus and cerebellum were drawn. The enzyme activities of AchE, NADHD, CCO, LDH, SDH, AcP, ANAE and AkP of these areas were observed with enzyme histochemical techniques. In another three kindled rats, two blank control rats and two NS control rats, the ultrastructure of neurons in hippocampus were observed. The results of experiments showed an increased activity of enzymes related to saccharometabolism and energy metabolism, indicating that the metabolism of brain in rats was increased by repeated kindling seizures. The mechanism of kindling seizure induced by CL may be related to inhibitory effect of CL on AchE activity of brain. The degeneration damage of brain neurons in kindled rats may result from using CL for a long time.

Acetylcholinesterase↗
PubMed1991

[Effects of SC1001-sodium on hippocampal kindled seizures by coriaria lactone in rabbits].

Healthy rabbits weighing 1.7-2.4 kg were used. According to Sawyer's atlas the stainless steel cannula and recording electrode were implanted into the left hippocampus of each animal. The kindling experiments were started one week after the surgical operation. For kindling, all animals received injection of 2 microliters of diluted solution containing 0.55 or 0.32 microgram of coriaria lactone (CL) every second day, through the single stainless steel cannula previously implanted in the hippocampus. Hippocampal EEG of all the animals was recorded by telemetric method and the behavior of them was observed at the same time. Eighteen fully kindled rabbits were separated into three groups. The SC1001 Na group of six rabbits was treated with SC1001 Na (100 mg/kg, i.m.), the PB Na group (six rabbits) received phenobarbital Na (30 mg/kg, i.m.), and the control group of six was treated with placebo (normal saline, i.m., in the same volume as that of the SC1001 Na injection); injections were administered once a day for two courses of treatment (one course of treatment was 1 week). The results of the experiment indicated that SC1001 Na (100 mg/kg) had certain effects on hippocampal kindled seizures induced by CL, but its curative effects were not more notable than those of PB Na (30 mg/kg).

Animals↗
PubMed1991

[Screening of active anti-inflammatory, immunosuppressive and antifertility components of Tripterygium wilfordii. III. A comparison of the antiinflammatory and immunosuppressive activities of 7 diterpene lactone epoxide compounds in vivo].

The half-effective dose(ED50), therapeutic index(TI) and certain safety factor(CSF) of 7 diterpene lactone epoxide compounds with antiinflammatory and immunosuppressive action extracted from Tripterygium wilfordii (TW) were assayed using croton oil-induced ear swelling and hemolysin-antibody formation mouse models. The results indicated that triptolide(T10), tripchlorolide(T4), triptonide(T7), tripdiolide(T8), triptolidenol(T9) and 16-hydroxytriptolide(L2) possessed both anti-inflammatory and immunosuppressive activities, while triptriolide(T11) had antiinflammatory activity only. The TI of the antiinflammatory action of 7 compounds were arranged in following order: T11(greater than 19), T10(17), T9(9.6), T4(9.0), T8(7.3), L2(6.6), T7(5.9), while the TI of the immunosuppressive action of 6 compounds were arranged in following order: T9(30.7), T4(16.7), L2(15.8), T10(13.7), T8(8.8), T7(7.5). The CSF parameters of both the activities of 7 compounds were all higher than 1. In which, the CSF of the immunosuppressive action of T9, T4 and L2 were 7.1, 5.1 and 3.6 respectively. These facts clearly demonstrate that the antiinflammatory and immunosuppressive compounds in TW are pluralistic. These differences among these compounds can be used as one of the bases for the evaluation and selection of these compounds. The above experiments conclude that the practical value of these compounds, however, will also depend on their content and yield rate in the herb, on the degree of difficulty in synthesizing these compounds, and on difficulty involved in the preparation of their derivatives. The future of these compounds will depend on the results of genetic toxicology studies as well.

Animals↗
PubMed1991

[Screening of active anti-inflammatory, immunosuppressive and antifertility components from Tripterygium wilfordii. IV. A comparison of the male antifertility activities of 7 diterpene lactone epoxide compounds].

The male antifertility activities under equal toxic dosages 1/10-1/60 LD50 and hemolysin antibody formation parameters under effective threshold dosages respectively of 7 diterpene lactone epoxide compounds extracted from Tripterygium wilfordii (TW) were assayed in mice. The results indicated that among the 7 compounds, 6 (T10, T4, T7, T8, T9 and L2) showed antifertility activities, the effective thresholds of T7, T8, T10 and L2 were below 1/40 LD50, those of T4 and T9 were below 1/60 LD50, while the other one (T11) did not. The above results reconfirm that the antifertility and immunosuppressive activities of all 6 active compounds are inseparable, but the formation of hemolysin antibodies was not inhibited under the total dosages which resulted in antifertility. The lowest dosages which were positive in terms of antifertility activity were 5-28 times lower than those for antiinflammatory activity and 5-12 times lower than those for immunosuppressive activity. And the total dosages necessary for effective immunosuppression were 0.9-1.8 times than the total dosages needed for effective antifertility. Finally, the value for the use of antifertility activity of these compounds, the influence of antifertility on antiinflammatory and immunosuppressive therapy, and the use of mouse models for screening of male antifertility activity are discussed.

Animals↗
PubMed1991

[Effects of electroacupuncture on epileptiform hippocampal unit activity by intracerebroventricular injection of coriaria lactone].

In our present study we build up a new experimental model in the rat for epilepsy by intracerebroventricular injection of Coriaria Lactone (CL) and examine the effects of electroacupuncture on epileptiform hippocampal unit activity. Three types of hippocampal units responding to CL were observed: a) positive units b) negative units and c) indifferent units. The activity of positive units may be the typical epileptiform hippocampal activity. The positive units can be inhibited by electroacupuncture (EA), while the negative units can be exhilarated by EA. No changes were observed in indifferent units. Inhibitory effects of positive units are different because of using different "acupoints". EA of Du-Mo and Taichong Kunlun in the other side of drug injection were significatively better than Taichong, Kunlun in the same side of drug injection. Effects of Du-Mo was significantly better than the effects of the points on the limb. Parameters of EA are significantly different in other side of limb points for inhibition of positive units: 5 V 1 Hz, 5 V 5 Hz greater than 1 V 5 Hz greater than 1 V 1 Hz. These data indicate that effects of EA are depend on amplitude of EA, and seem not to be concern with frequencies of EA. The amplitude and frequency of hippocampal EEG spikes can be inhibited by EA. The inhibitory role of EA on epileptiform discharges is also discussed in this paper.

Animals↗
PubMed1990

[Variation of cAMP in cerebral cortex and hippocampus in seizure mice induced by coriaria lactone].

To study the relationship between cAMP and epilepsy, we investigated the effects of coriaria lactone (CL) on the levels of cAMP in cerebral cortex and hippocampus. Fifty normal WC1 mice were divided into 5 groups. All groups were injected with CL (2.5 mg/kg, i.m.), except the control group which was injected with NS. The concentrations of cAMP were measured after the animals had been immersed in liquid nitrogen to die at different phases of seizure development induced by CL (before seizures, in mild seizures, during severe seizures, and after severe seizures). The results indicated that the levels of cAMP in both cerebral cortex and hippocampus were significantly increased (1.73-fold and 1.33-fold) in severe seizure, and they continuously increased (1.85-fold and 1.45-fold) after severe seizures. On the other hand, no changes of cAMP were observed in mild seizures and before seizures. These data suggested that accumulation of cAMP is probably the result of seizure activity rather than the cause of seizure.

Animals↗
PubMedDate not supplied

The effects of alpha-methylene-gamma-lactone purines and pyrimidines on L1210 lymphoid leukemia nucleic acid metabolism.

Purine and pyrimidine adducts of alpha-methylene-gamma-lactone demonstrated potent cytotoxicity against murine L1210 lymphoid leukemia growth as well as a variety of human tissue cultured tumors. The most potent compound, 9-[(2-methyl-4-methylene-5-oxotetrahydrofuran-2-yl)-methyl 1] adenine 1 demonstrated significant inhibition of DNA synthesis in L1210 leukemic cells with moderate inhibition of protein synthesis. The major enzyme activities inhibited by 1 were DNA polymerase alpha, ribonucleoside reductase and t-RNA polymerase with marginal inhibition of thymidine kinase, TMP kinase, PRPP amidotransferase and IMP dehydrogenase. The inhibition of DNA polymerase alpha activity by 1 was evident at the lowest concentration 25 microM and was evident within 15 min incubation at 100 microM. The magnitude of enzyme inhibition was consistent with the observed DNA synthesis inhibition by 1. The only deoxyribonucleotide level reduced by 1 was the dATP pool level. U.V. absorption of DNA after interacting with 1 demonstrated a hyperchromic effect and L1210 DNA strand scission was observed after 24 hr incubation with 1 suggesting some type of interference with the DNA template by the drug.

Animals↗
PubMed1990

[A kindling model of epilepsy induced by intraperitoneal injection of coriaria lactone in rats].

Fifty adult male Sprague-Dawley rats were divided into five groups. Intraperitoneal injections of various doses of coriaria lactone (CL, 0.75, 1.25, 1.75, and 2.0 mg/kg) and normal saline were given respectively per 2 days. The behavior of the rats was observed and the ECoG was recorded by telemetric method. The results of experiments show that a kindling model of epilepsy can be established by intraperitoneal injection of CL in rats. This chronic experimental model is of value for application because it is easily established and the rate of being kindled is relatively high, but the mortality is low, and the kindling effect can last well. The model can avert the pathological change caused by artificial injury to brain, so it is advantageous to the research on neurochemistry and ultrastructure. In our experimental condition, it is optimal to select 1.25 mg/kg or 1.75 mg/kg as the dosage of CL for establishing kindling model.

Animals↗
PubMed1990

[Coriaria lactone-induced epileptiform activity in the hippocampal slices of rat].

Coriaria lactone (CL) is an active constituent of a medicinal herb used as psychosolytic in traditional Chinese medicine. Recently it has been found that CL appears to act as a convulsant agent. Subsequently both acute and chronic epilepsy models caused by CL have been established successfully. In order to observe further the epileptogenic effects of CL in vitro, the hippocampal slice technique was used in experiments with 36 slices. The results are as follows: Addition of CL to the perfusion bathing the slices of rat hippocampus increased evoked-response in body layer of CA1 in a dose-dependent manner, and induced epileptiform burst. CL augmented population spike of CA1 pyramidal neurons triggered by either orthodromic stimulus (through synapses) or antidromic stimulus (direct effect on the axon of CA1 pyramidal cells) without alteration of presynaptic fiber volley and field-EPSP, and there was no significant change in latency of burst. Finally GABA had a weak effect on CL-induced epileptiform activity. These observations suggest that CL probably has a direct effect on the soma of pyramidal neurons, CL-induced epileptiform burst may be a result of altering the innate capacity of burst and increasing the intrinsic excitability of pyramidal cell membranes.

Animals↗
PubMed1989

Critical and controlled tests of activity of a macrocyclic lactone (compound F28249-alpha) against natural infections in internal parasites of equids.

Thirteen critical tests (n = 11 horses and 2 ponies) and 4 controlled tests (n = 4 donkeys and 6 horses) were performed to evaluate the activity of the experimental macrocyclic lactone compound F28249-alpha against internal parasites of equids. In the critical tests, activity was determined mainly against the large parasites, but 1 critical test also included benzimidazole-resistant small strongyles. In the controlled tests, evaluation of drug activity included large parasites and stomach worms in all 4 tests, and lungworms in 2 tests. The period between treatment and euthanasia was 6 to 9 days for the critical tests and 14, 17, or 52 days for the controlled tests. The compound was administered by stomach tube at dose rates of 1, 2, 3, 3.5, or 4 mg/kg of body weight. In the critical tests, removal at all 5 dose rates was 100% for Gasterophilus nasalis (2nd and 3rd instars), Parascaris equorum (mature), Strongylus vulgaris, and Strongulus edentatus from the gastrointestinal tract. For Gasterophilus intestinalis in the stomach, mean removals of 2nd instars were 88% at the rate of 2 mg/kg and 93% to 100% at rates greater than or equal to 3 mg/kg. For 3rd instars, mean removals were 7% at 1 mg/kg, 77% at 2 mg/kg, 90% at 3 mg/kg, and 98% at 3.5 mg/kg. Discharge of G intestinalis in feces was typically a slow, prolonged process and probably higher removal values, especially at lower dose rates, would have attended a longer interval after treatment before necropsy examination.(ABSTRACT TRUNCATED AT 250 WORDS)

Abdominal Muscles↗
PubMed1986

Rhizoxin, a macrocyclic lactone antibiotic, as a new antitumor agent against human and murine tumor cells and their vincristine-resistant sublines.

Rhizoxin, isolated from a plant pathogenic fungus which causes rice seedling blight, inhibits the mitosis of the tumor cells in a manner similar to that of Vinca alkaloids as revealed by morphological study and flow cytometry analysis. This new 16-membered macrocyclic lactone showed similar chemotherapeutic effects to those of vincristine against L1210 and P388 leukemia-bearing mice. The drug is also effective against B16 melanoma inoculated i.p. or s.c. Rhizoxin, in contrast to the ansamacrolide, maytansine, was effective against human and murine tumor cells resistant to vincristine and Adriamycin in vitro and in vivo. A maximum 60% increase in life span was obtained in mice inoculated with P388 leukemia resistant to vincristine. Rhizoxin showed greater cytotoxicity in cultured tumor cells than did vincristine. Rhizoxin seems to bear consideration for further development as a new chemotherapeutic agent.

Animals↗
PubMedDate not supplied

Sequiterpene lactones. Part XXV. Studies on the mode of action. The cellular and molecular basis of cytostatic action.

Two compounds, derivatives of the sesquiterpene lactones (SL), ALA and URSA, on the basis of the high antitumor activity in vitro and in vivo systems, were selected as models, in order to study the mechanism of action of this drug class. Using cytologic, morphologic and isotopic methods the following were demonstrated: 1) At a subtoxic conc., 0.28 microM, arrest the HeLa cell in its interphase (G1, and/or S, G2). 2) At a higher conc. of 28.0 microM, complete and irreversible cytotoxic effects with pyknosis and karyorrhexis. 3) At a conc. of 56.0 microM, inhibition of protein biosynthesis by 94% and RNA by 81--92%. 4) At a conc. of 2.5 microM inhibition by 80% of translation processes. Inhibition of DNA biosynthesis seems to be doubtful. A preliminary hypothetical model of the cellular and molecular mechanism of SL, partly explanatory also of the cytostatic effect, has been proposed.

Antineoplastic Agents, Phytogenic↗
PubMed1979

alpha, beta-Unsaturated gamma-lactones correlations between lipophilicity and biological activity.

A homogeneous series of alpha, beta-unsaturated gamma-lactones was prepared. Their in vitro activity against various microorganisms was quantitatively correlated, with the Hansch approach, to their lipophilicity, expressed by Rm chromatographic values. Although all the experimental results show a parabolic dependence, only in few cases the parabolic model calculated by Hansch fits to them. In most cases it was possible to find a good fitting between the ascending side of the parabola and the linear equation of Hansch. The meaning of the results and their utilization for future work are discussed.

Bacteria↗
PubMedDate not supplied

[Relationship between ion channel properties and the structure of the lactone ring of polyene antibiotic molecules].

Properties of ionic channels created by amphoterecin B, nystatine and mycoheptin in phospholipid--cholesterol bilayer have been compared. Ionic conductivity and selectivity of channels as well as the frequency of transitions between an open state and a closed one depend on lacton ring structure. Appearance of one more carbonyl group in mycoheptin molecule leads to a decrease of channel anion permeability. Any pair of these antibiotics being added into different aqueous solutions create combined channels. These data confirm hypothesis that polyene antibiotics create channels of two half-pores formed in different monolayers of the membrane.

Amphotericin B↗
PubMedDate not supplied

[Significance of the ability of Candida Berhout to assimilate D-glucuronic acid, D-glucono-delta-lactone and 5-keto-D-gluconate for systematics].

117 Candida strains representing 76 species and varieties were studied. Most of them readily assimilated glucono-delta-lactone with an exception of species which were imperfect analogues of Pichia spp. with round ascospores, Saccharomyces spp. and Kluyveromyces spp. The test for assimilation of 5-keto-D-gluconate can be used to differentiate varieties of C. guilliermondii, C. pelliculosa, and species C. zeylanoides and C. vinaria. The group of glucuronate-positive species belonging to the genus Candida comprises both ascomycetous and basidiomycetous organisms. The former lack the urease activity. Among the latter, C. curvata, C. humicola, C. marina and C. podzolica produce extracellular polysaccharides identical in the monosaccharide composition to polysaccharides of cryptococci. These four species should be included into the genus Cryptococcus.

Candida↗
PubMed1995

[Coriaria lactone on gamma-aminobutyric acid secretion and glutamic acid decarboxylase and its receptor binding in rat].

The effects of coriaria lactone (CL) on gamma-aminobutyric acid (GABA) secretion, glutamic acid decarboxylase (GAD) activity and glutamate (Glu) receptor binding were studied by using cultured neurons, P2 component and synaptic membranes from rat cerebral cortex. It was found that GABA secretion was depressed by CL, the depression rate was 8.3%, 10.6%, 14.5% at 12h 24h 48h respectively. GAD activity was depressed by CL in concentration of 0.15-150 mumol/L. The depression rate was 1.32%, 5.96%, 13.24%, 18.76% respectively. The Glu receptor binding capability was decreased by CL with obvious dose-effect relation in the extent of 2.8-350 mumol/L; the decrease rate was 4.4%, 12.7%, 15.2%, 19.5% respectively. The difference was significant as compared to control (P < 0.01).

Animals↗