Studies on the constituents of Leonurus sibiricus L. (1/17)

Two new furanoditerpene-lactones, LS-1 (1) and LS-2 (2), were isolated along with four known furanoditerpene-lactones 3, 4, 5 and 6 from the aerial part of Leonurus sibiricus L. The structures of the new compounds were determined by spectroscopic means. Compounds 1-6 isolated here exhibited moderate cytotoxic activity (IC(50)=50-60 microg/ml) against leukemia cells (L 1210) in tissue culture.  (+info)

New labdane-type diterpenoids from Leonurus heterophyllus SW. (2/17)

Five new natural labdane-type diterpenoids (5-9), designated leoheteronins A-E, together with four known diterpenoids (1-4), two phytosterols as a mixture of beta-sitosterol and stigmasterol, and the flavone genkwanin (10) were isolated from the aerial parts of Leonurus heterophyllus SW. (Lamiaceae) collected in northern Vietnam. Compound 1 was isolated for the first time from a Leonurus species, and 10 is considered to be a chemotaxonomic marker of the Leonurus genus. Their structures were determined using spectroscopic analyses.  (+info)

New bis-spirolabdane-type diterpenoids from Leonurus heterophyllus Sw. (3/17)

Twelve natural bis-spirolabdane-type diterpenoids, including eight new, named leoheteronones A-E, 15-epileoheteronones B, D, and E, and four known leopersin B, 15-epileopersin B, leopersin C, and 15-epileopersin C, together with hispanone and galeopsin were isolated from the aerial parts of the medicinal plant Leonurus heterophyllus SW. (Lamiaceae) grown in Vietnam. Their structures were determined by spectroscopic analyses. The current study emphasized the accumulation of C-15 oxygenated bis-spirolabdane-type diterpenoids of both 13R and 13S configurations in L. heterophyllus.  (+info)

Expression of a novel small antimicrobial protein from the seeds of motherwort (Leonurus japonicus) confers disease resistance in tobacco. (4/17)

Medicinal plants are valuable resources of natural antimicrobial materials. A novel small protein with antimicrobial activities, designated LJAMP1, was purified from the seeds of a medicinal herb, motherwort (Leonurus japonicus Houtt). LJAMP1 is a heat-stable protein with a molecular mass of 7.8 kDa and a determined isoelectric point of 8.2. In vitro assays showed that LJAMP1 inhibits the growth of an array of fungi and bacteria. The hyphal growth inhibition by LJAMP1 was more evident against hyphomycete fungi, such as Alternaria alternata, Cercospora personata, and Aspergillus niger. The N-terminal amino acid sequence of LJAMP1 was determined, and its coding gene was consequently cloned by the rapid amplification of cDNA ends. The gene LJAMP1 has no intron and encodes a polypeptide of 95 amino acids, in which the first 27 residues was deduced as a signal peptide. The mature LJAMP1 shows relatively low identity to plant napin-like storage proteins. Northern blot assays revealed that LJAMP1 is expressed preferentially in seeds. Bioassays in transgenic tobacco demonstrated that that overexpression of LJAMP1 significantly enhanced the resistance of tobacco against not only the fungal pathogen A. alternata but also the bacterial pathogen Ralstonia solanacearum, while no visible alteration in plant growth and development was observed.  (+info)

The comparison of anti-oxidative kinetics in vitro of the fluid extract from maidenhair tree, motherwort and hawthorn. (5/17)

The aim of the study was to perform a quantitative analysis of fluid extracts of maidenhair tree (Ginkgo biloba L.), motherwort (Leonurus cardiaca L.) and hawthorn (Crataegus monogyna Jacq.), to evaluate their antioxidant activity and to compare their ability to inactivate free radicals. The antioxidant activity was measured using the DPPH*and the ABTS*+ radical scavenging reaction systems. The study showed that the manifestation of the radical scavenging capacity in the DPPH* reaction system was in the following order: the fluid extract of hawthorn (70.37 +/- 0.80%) > the fluid extract of maidenhair tree (82.63 +/- 0.23%) > the fluid extract of motherwort (84.89 +/- 0.18%), while in the ABTS*+ reaction system, the manifestation of the radical scavenging capacity was in the following order: the fluid extract of hawthorn (87.09 +/- 0.55%) > the fluid extract of motherwort (88.28 +/- 1.06%) > the fluid extract of maidenhair tree (88.39 +/- 0.72%). The results showed that in the DPPH* reaction system, fluid extract of motherwort manifested higher antioxidant activity, compared to the fluid extracts of maidenhair tree and hawthorn. By contrast, in the ABTS*+ reaction system, higher antioxidant activity was found in the fluid extract of maidenhair tree, compared to the fluid extracts of motherwort and hawthorn. This would suggest that preparations manufactured from these herbal raw materials could be used as effective preventive means and valuable additional remedies in the treatment of diseases caused by oxidative stress.  (+info)

Leonurus sibiricus herb extract suppresses oxidative stress and ameliorates hypercholesterolemia in C57BL/6 mice and TNF-alpha induced expression of adhesion molecules and lectin-like oxidized LDL receptor-1 in human umbilical vein endothelial cells. (6/17)

In Leonurus sibiricus herb extract (LHE)-supplemented animals, plasma cholesterol decreased and high-density lipoprotein-cholesterol increased, resulting in a lowered atherogenic index. The plasma trolox equivalent antioxidant capacity, levels of hepatic thiobarbituric acid-reactive substances, and protein carbonyl values decreased significantly in LHE-supplemented mice (p<0.05), whereas the hepatic antioxidant indicators were all significantly elevated (p<0.05). In human umbilical vein endothelial cells stimulated with tumor necrosis factor alpha, LHE significantly suppressed intracellular reactive oxygen species, LOX-1, and adhesion molecules. LHE supplementation may modulate the lipoprotein composition and attenuate oxidative stress by elevated antioxidant processes, thus suppressing the activation of inflammatory mediators. This is a possible mechanism of the anti-atherogenic effect.  (+info)

Development and validation of an UPLC-DAD-MS method for the determination of leonurine in Chinese motherwort (Leonurus japonicus). (7/17)

In the present study, an ultra-performance liquid chromatography method with diode array detection (UPLC-DAD) was developed for the analysis and determination of leonurine from motherwort (Leonurus japonicus), a traditional Chinese medicinal plant. This method was validated in terms of specificity, linearity (R(2) = 0.9995, linear range: 0.005 ~ 0.5 mg/mL), precision (< 5.0% RSD), and recovery (103.2%). The extracted amount of leonurine is 0.15 mg/g. Moreover, the target analyte was identified or tentatively characterized using UPLC coupled with electrospary tandem mass spectrometry (UPLC-ESI-MS).  (+info)

Neuroprotective effects of leonurine on ischemia/reperfusion-induced mitochondrial dysfunctions in rat cerebral cortex. (8/17)

Ischemic brain is particularly susceptible to free radicals mediated secondary neuronal damage, especially mitochondrial dysfunctions. Chinese Herbal Medicine with antioxidant properties is believed to have potential therapeutic effect. Leonurine, an alkaloid present in Herba Leonuri (HL), has shown biological effects such as antioxidant, anticoagulant, anti-apoptosis and protection against ischemic heart disease. In this study, neuroprotective effects of leonurine against cerebral ischemia/reperfusion-induced mitochondrial dysfunctions in cortex were evaluated. We used transient rat middle cerebral artery occlusion (MCAO) model of brain ischemia. The rats were treated with their respective treatments for 1 week prior to the MCAO. We found that leonurine significantly improved neurological outcome and reduced ischemia/reperfusion (I/R)-induced cerebral infarction 24 h after MCAO. Leonurine decreased reactive oxygen species (ROS) level in mitochondria isolated from ischemic cortex, which was increased by MCAO. Terminal deoxyuridine triphosphate (dUTP) Nick-End Labeling (TUNEL) staining showed anti-apoptotic effect of leonurine on ischemic cortex. Western blot analysis showed a marked decrease in the expression of Bax and an increase of Bcl-2 as a result of leonurine treatment. The attenuation of mitochondrial membrane swelling, restore of mitochondrial membrane potential and content of cytochrome c (Cyt-C) in mitochondria isolated from ischemic cortex could also be observed in leonurine treated group. The findings of this study suggest that leonurine has promising therapeutic effect for ischemic stroke treatment through antioxidant and anti-apoptotic mechanisms.  (+info)