Determination of astragaloside IV in Radix astragali (Astragalus membranaceus var. monghulicus) using high-performance liquid chromatography with evaporative light-scattering detection. (1/90)

A reverse-phase high-performance liquid chromatographic method is developed for the determination of astragaloside IV, a characteristic constituent in Radix Astragali. Samples are analyzed by means of a reverse-phase column (Zorbax Eclipse XDB C18) using acetonitrile and water under gradient conditions as the mobile phase for 30 min. An evaporative light-scattering detector is used and set at an evaporating temperature of 43 degrees C with a nebulizing gas (compressed air) pressure of 3.4 bar. The detection limit (signal-to-noise ratio > 5) of astragaloside IV is 40 ng on-column.  (+info)

Trojanosides I-K: new cycloartane-type glycosides from the aerial parts of Astragalus trojanus. (2/90)

Three new cycloartane-type triterpene glycosides have been isolated from the aerial parts of Astragalus trojanus. The structures were established mainly by a combination of one- and two-dimensional NMR techniques [1H-1H-correlation spectroscopy (COSY), 1H-13C-heteronuclear multiple quantum correlation spectroscopy (HMQC), and 1H-13C-heteronuclear multiple-bond correlation spectroscopy (HMBC)] and high resolution electrospray ionization mass spectrometry (HR-ESI-MS) as 3-O-beta-(2',3'-di-O-acetyl)-D-xylopyranosyl-6-O-beta-D-glucopyranosyl-16-O- acetoxy-20(R),24(S)-epoxycycloartane-3beta,6alpha,16beta,25-tetrol, 3-0-[alpha-L-rhamnopyranosyl-(1-->2)-beta-(3',4'-di-O-acetyl)-D-xylopyranosyll-6- O-beta-D-xylopyranosyl-20(R),24(S)-epoxycycloartane-3p,6alpha,16beta,25-tetrol, 3-O-beta-D-xylopyranosyl-6,16-di-O-beta-D-glucopyranosyl-20(R)24(S)-epoxycycloart ane-3beta,6alpha,16beta,25-tetrol.  (+info)

Astragalus mongholicus and Angelica sinensis compound alleviates nephrotic hyperlipidemia in rats. (3/90)

OBJECTIVE: To investigate the mechanism of lipid-lowering effect of the Astragalus mongholicus and Angelica sinensis compound (A&A) on nephrotic hyperlipidemia in rats. METHODS: Rats with nephrotic syndrome from accelerated nephrotoxic serum nephritis were used. They were divided into two groups: A&A treatment group and nephrotic control group. Normal rats were used as a normal control group. Serum lipids, serum lipoprotein lipase (LPL) and lecithin-cholesterol acyltransferase (LCAT) were assayed biochemically and enzymatically. mRNAs of hepatic hydroxy-methyl glutaryl-CoA reductase (HMG-CoA-R) and low-density lipoprotein receptor (LDL-R) were assessed by Northern blot. RESULTS: In nephrotic control group hyperlipidemia was found. The activities of serum LPL and LCAT were low. Hepatic HMG-CoA-R mRNA increased temporarily at the early stage while LDL-R mRNA decreased gradually. In A&A treatment group, serum total cholesterol (TC), triglyceride (TG), low-density lipoproteins (LDL) and very low-density lipoproteins (VLDL) were significantly lower than those in nephrotic control group. There was no change in the amount of hepatic HMG-CoA-R mRNA, but hepatic LDL-R mRNA and activities of serum LPL and LCAT increased significantly. CONCLUSIONS: A&A alleviates hyperlipidemia considerably in nephrotic rats. A&A improves disorders of lipid metabolism perhaps through up-regulating the expression of hepatic LDL-R gene and through increasing the activities of serum LPL and LCAT.  (+info)

Conditioning taste aversions to locoweed (Oxytropis sericea) in horses. (4/90)

Locoweed (Oxytropis sericea) is a serious poisoning problem for horses grazing on infested rangelands in the western United States. Our objectives were to determine 1) whether lithium chloride or apomorphine would condition aversions to palatable foods, and at what doses, and 2) whether horses could be averted to fresh locoweed in a pen and grazing situation. Apomorphine was not an acceptable aversive agent because at the dose required to condition an aversion (> or = 0.17 mg/kg BW), apomorphine induced unacceptable behavioral effects. Lithium chloride given via stomach tube at 190 mg/kg BW conditioned strong and persistent aversions to palatable feeds with minor signs of distress. Pen and grazing tests were conducted in Colorado to determine if horses could be averted to fresh locoweed. Pen tests indicated that most horses (5/6) were completely averted from locoweed. Treated horses ate 34 g of fresh locoweed compared to 135 g for controls (P < 0.01) during three pen tests when offered 150 g per test. One horse (T) in the treatment group ate locoweed each time it was offered in the pen, but ate no locoweed while grazing. In the grazing trial, control horses averaged 8.6% of bites of locoweed (P < 0.01) during the grazing portion of the study, whereas treated horses averaged <0.5%. One treated horse (S) accounted for all consumption; he consumed 15% of his bites as locoweed in a grazing bout on d 2 of the field study. Thereafter, he was dosed a second time with lithium chloride and ate no locoweed in the subsequent 5 d. Three of six horses required two pairings of lithium chloride with fresh locoweed to condition a complete aversion. The results of this study indicate that horses can be averted from locoweed using lithium chloride as an aversive agent, and this may provide a management tool to reduce the risk of intoxication for horses grazing locoweed-infested rangeland.  (+info)

Identification of a gene associated with astragalus and angelica's renal protective effects by silver staining mRNA differential display. (5/90)

OBJECTIVE: To identify genes associated with the chronic progression of renal disease and a stragalus and angelica (A&A)'s renal protective effects. METHODS: The technique of silver staining mRNA differential display (DD) was used to investigate changes of gene expression in normal, sclerotic and A&A treated sclerotic kidneys. We isolated genes differentially expressed during the progression of renal disease which could be normalized by A&A. RESULTS: Several genes related to A&A's protective effects were isolated and one of them was confirmed by Northern blot. CONCLUSION: Silver staining mRNA differential display is a simple and effective technique for isolating differentially expressed genes. The isolated new gene may be related to the progression of chronic renal disease and contribute to A&A's protective effects.  (+info)

Reducing fatigue of athletes following oral administration of huangqi jianzhong tang. (6/90)

AIM: To study the effect of Huangqi Jianzhong Tang in reducing fatigue improvement in athletes. METHODS: Twelve athletes were randomly separated into a control group, whose members were administered with placebos, and the experimental group, whose members were administered with Huangqi Jianzhong Tang. During the eight weeks of the experiment, test subjects continued exercise as usual. Preliminary and final exhaustion times, anaerobic thresholds, and kinetic energies were determined. RESULTS: Huangqi Jianzhong Tang might increase exhaustion time, positively influence anaerobic threshold, and also enhance recovery from fatigue. CONCLUSION: Huangqi Jianzhong Tang reduced fatigue by increasing the oxygen uptake and the systemic utility of oxygen.  (+info)

Chemical form and distribution of selenium and sulfur in the selenium hyperaccumulator Astragalus bisulcatus. (7/90)

In its natural habitat, Astragalus bisulcatus can accumulate up to 0.65% (w/w) selenium (Se) in its shoot dry weight. X-ray absorption spectroscopy has been used to examine the selenium biochemistry of A. bisulcatus. High concentrations of the nonprotein amino acid Se-methylseleno-cysteine (Cys) are present in young leaves of A. bisulcatus, but in more mature leaves, the Se-methylseleno-Cys concentration is lower, and selenate predominates. Seleno-Cys methyltransferase is the enzyme responsible for the biosynthesis of Se-methylseleno-Cys from seleno-Cys and S-methyl-methionine. Seleno-Cys methyltransferase is found to be expressed in A. bisulcatus leaves of all ages, and thus the biosynthesis of Se-methylseleno-Cys in older leaves is limited earlier in the metabolic pathway, probably by an inability to chemically reduce selenate. A comparative study of sulfur (S) and Se in A. bisulcatus using x-ray absorption spectroscopy indicates similar trends for oxidized and reduced Se and S species, but also indicates that the proportions of these differ significantly. These results also indicate that sulfate and selenate reduction are developmentally correlated, and they suggest important differences between S and Se biochemistries.  (+info)

Tannic acid is an inhibitor of CXCL12 (SDF-1alpha)/CXCR4 with antiangiogenic activity. (8/90)

PURPOSE: Increasing evidence suggests that interaction between the chemoattractant CXCL12/stromal cell-derived factor-1alpha and its receptor CXCR4 plays a pivotal role in the metastasis of various tumors. Our previous studies showed that multi-component Chinese herbal medicines inhibited the effects of CXCL12/CXCR4. As a result of sequential chromatographic fractionation of one herbal medicine ingredient, Lianqiao (fruit of Forsythia suspensa), we observed that tannins were, at least in part, responsible for this activity. The aim of this study was to assess the anti-CXCL12/CXCR4 activity of a commercial tannic acid and evaluate its potential to inhibit tumor cell migration and angiogenesis in vitro. EXPERIMENTAL DESIGN: The inhibitory effect of tannic acid on CXCL12/CXCR4 was measured by chemotaxis assay, ligand binding assay, and fluorescence-activated cell sorter analysis. The antiangiogenic effect of tannic acid was assessed by in vitro endothelial cell tube formation. RESULTS: Tannic acid, at nontoxic concentrations, specifically inhibited CXCL12-induced human monocyte migration (IC(50), 7.5 micro g/ml) but did not inhibit CCL2-, CCL3-, CCL5-, formylmethionylleucylphenylalanine (fMLP)-, or C5a-induced migration. The compound markedly blocked CXCL12 binding to THP-1 cells (IC(50), 0.36 micro g/ml). Tannic acid also inhibited CXCL12-induced, but not epidermal growth factor-induced, migration of MDA 231 breast tumor cells. Additionally, 0.5 micro g/ml of tannic acid selectively inhibited CXCL12-mediated, but not basic fibroblast growth factor- or endothelial cell growth supplement-mediated, bovine aorta endothelial cell capillary tube formation. CONCLUSION: These studies indicate that tannic acid is a novel selective CXCL12/CXCR4 antagonist and consequently may provide a mechanistic basis for the reported antitumor and anti-inflammatory properties of tannic acid.  (+info)