Membranaceus Root Research Articles

Astragaloside content in the periderm, cortex, and xylem of Astragalus membranaceus root

Astragalosides are among the most predominant of the bioactive compounds in the root of Astragalus membranaceus and are differentially concentrated depending on the anatomical part of the root in question. The aim of this study was to analyse astragaloside contents in the periderm, cortex, and xylem of A. membranaceus root, and to compare the contents between peeled and unpeeled roots. Total astragalosides in the periderm were about 8-fold more concentrated than in the cortex, and 28-fold more concentrated than in the xylem. The dry weight percentages of total astragalosides in primary roots were 43.5% in the periderm, 47.2% in the cortex, and 9.30% in the xylem. Furthermore, unpeeled main (primary) roots were enriched in astragalosides by 1.46-fold compared with peeled main roots, whereas unpeeled lateral roots were enriched by 2.33-fold compared with peeled lateral roots. In conclusion, the periderm is the most astragaloside-rich part of the root of A. membranaceus. Therefore, it is necessary to preserve the periderm in order to supply astragaloside-rich roots for use as health food supplements.

Functional Assessment of Pharmacological Telomerase Activators in Human T Cells

Telomeres are structures at the ends of chromosomes that shorten during cell division and eventually signal an irreversible state of growth arrest known as cellular senescence. To delay this cellular aging, human T cells, which are critical in the immune control over infections and cancer, activate the enzyme telomerase, which binds and extends the telomeres. Several different extracts from the Astragalus membranaceus root have been documented to activate telomerase activity in human T cells. The objective of this research was to compare two extracts from Astragalus membranaceus, TA-65 and HTA, for their effects on both telomerase and proliferative activity of human CD4 and CD8 T cells. Our results demonstrate that, TA-65 increased telomerase activity significantly (1.3 to 3.3-fold relative to controls) in T cell cultures from six donors tested, whereas HTA only increased telomerase levels in two out of six donors. We also demonstrate that TA-65 activates telomerase by a MAPK- specific pathway. Finally, we determine that during a three-day culture period, only the T cells treated with the TA-65 extract showed a statistically significant increase in proliferative activity. Our results underscore the importance of comparing multiple telomerase activators within the same experiment, and of including functional assays in addition to measuring telomerase activity.

Effects of Astragalus membranaceus root processed to different particle sizes on growth performance, antioxidant status, and serum metabolites of broiler chickens1

The objectives of this study were to assess the effects of supplementation of Astragalus membranaceus root powder (AMP) and AMP processed to different particle sizes on growth performance, antioxidant status, and serum metabolites of broiler chickens. The experiment was conducted with one hundred twenty 1-d-old Arbor Acres broilers in 5 groups of 4 cages and for both starter (0 to 21 d) and grower (22 to 42 d) phases. The treatments were basal diet only (control) and basal diet supplemented with 5 g/kg of diet of AMP processed to particle sizes of 300, 149, 75, or 37 µm. Average daily gain, ADFI, and feed conversion rate (FCR) were determined weekly, and carcass yield, serum antioxidant enzyme activity, and metabolites were determined at 21 and 42 d of the experiment. Supplementation of AMP increased (P < 0.01) activities of total superoxide dismutase (TSOD) and glutathione peroxidase (GSHPx), but reduced (P < 0.01) concentrations of malondialdehyde (MDA) and cholesterol in the serum of chickens at 21 and 42 d. Reducing AMP particle sizes from 300 to 37 µm linearly increased (P < 0.01) TSOD and GSHPx activities at 21 and 42 d, but linearly decreased (P < 0.01) MDA at 42 d. Concentrations of total protein, albumin, and globulin in the serum were also increased (P < 0.05) or tended to be increased (P = 0.05 to 0.10) by AMP and linearly increased (P < 0.01) as the AMP particle sizes decreased. However, both treatments had no effect on ADG, ADFI, or FCR throughout the entire experiment period, although carcass yield increased (P < 0.05) at 42 d. Dietary supplementation of AMP at the concentration of 5 g/kg of diet enhanced serum antioxidant status and its efficacy linearly increased as the AMP particle size decreased from 300 to 37 µm, but had no effect on growth performance of broilers.

Effects of Astragalus membranaceus on laying performance and antioxidant status of laying hens

SUMMARY Interest in the use of natural feed additives in the animal and poultry industries is growing. In the present study, we assessed the effects of dietary supplementation of Astragalus membranaceus root powder (AMP) on the laying performance and serum and egg yolk antioxidant status of laying hens. Four groups (135 each) of laying hens fed a corn- and soybean meal-based diet were supplemented with 0, 5, 10, or 15 g/kg of diet of AMP for 10 wk, and their laying performance and serum and egg yolk antioxidant status were measured. Supplementation of AMP did not affect ADFI or average egg weight but did linearly increase egg mass of the laying hens. Antioxidant status of the serum and egg yolk was improved, as judged by an increase in antioxidant enzymatic activities and a decrease in concentrations of oxidized products, with supplementation of AMP in a dose-dependent manner. In conclusion, supplementing a cornand soybean meal-based laying hen diet with AMP at levels of 5 to 10 g/kg of diet had the potential to improve the antioxidant status of laying hens and improve laying performance.

Effects of dietary Astragalus polysaccharide and Astragalus membranaceus root supplementation on growth performance, rumen fermentation, immune responses, and antioxidant status of lambs

The aim of this study was to investigate effects of dietary Astragalus membranaceus root (AMT) and Astragalus polysaccharide (APS) supplementation on growth performance, blood metabolites, rumen fermentation, immune responses and antioxidant status of weaned lambs. Twenty-four male Ujumqin weaned lambs (a local breed) with average age of 60±10.3d and similar genetic background were randomly assigned to one of three treatments for a 30d feeding period. Treatments consisted of the lambs’ basal diets with addition of: (1) nothing (control), (2) 15g/kg APS or (3) 50g/kg AMT of the diet (dry matter (DM) basis). Blood samples were collected at day 0 and 30 and ruminal fluid samples at day 0, 15 and 30. Results showed that APS supplementation increased DM intake of lambs (P=0.003), but that average daily gain, feed efficiency and apparent digestibility of nutrients did not differ among treatments. Concentrations of ammonia N (P=0.004) and total volatile fatty acids (P=0.005) were affected by an interaction between treatment and feeding time. Both APS and AMT feeding increased propionic acid (P=0.025) which resulted in a reduction in the acetic acid to propionic acid ratios in ruminal fluid (P=0.014). Feeding APS and AMT increased total antioxidant capacity (P<0.001) and total superoxide dismutase activities (P<0.001), and decreased cortisol levels (P<0.001) in plasma. However, blood plasma metabolites such as blood urea N, high and low density lipoprotein–cholesterol, triglyceride, glucose and total protein, which are reflective of animal metabolism, were not affected by APS and AMT feeding. Only dietary AMT supplementation affected immune responses, including increased immunoglobulin M production (P<0.001) and lymphocyte numbers (P=0.024) in whole blood. Results suggest that APS and AMT feeding mainly improved antioxidant capacity and affected rumen fermentation patterns of lambs, while AMT supplementation affected immunity, but both additives failed to improve apparent digestibility of nutrients in weaned lambs.

Acute toxicity studies of Croton membranaceus root extract

Croton membranaceus root and leaf extracts are used in the Bahamas to aromatize tobacco, in Nigeria to improve digestion, and in Ghana, for benign prostate hyperplasia. Despite claims of success there is paucity of information on its toxicity. The aim of this study was to determine if Croton membranaceus has acute toxicity properties. Roots were air-dried in a solar dryer for one week before milling. The powder was extracted with 96% ethanol, freeze-dried and re-extracted with distilled water and freeze-dried. 15 male Sprague-Dawley rats (180-200 g) were divided equally into 2 treatment groups [low dose (LD) and high dose (HD)], plus a control group (C). LD and HD received 1500 and 3000 mg/kg b.wt. Croton membranaceus aqueous extract, respectively, one time and observed for 14 days. Haematological [Full Blood Count and haemoglobin (Hb)], biochemical [bilirubin, alanine aminotransferase (ALA), aspartate aminotransferase (AST), total protein, albumin, globulin, alkaline phosphatise (ALP), γ-glutamyltranspetidase (GGT), urea, creatinine, creatinine kinase - Muscle and Brain (CK-MB), creatinine kinase - Total (CK-R)] examinations were performed. Control group's CK-MB (5444±534 U/L) and LD group CK-MB (4014±1016 U/L) were significantly different (p<0.05). Control and the HD group CK-MB (3955±1135 U/L) were significantly different (p<0.05). Both LD and HD CK-R levels (697±197U/L and 732±203 U/L, respectively), were lower than the control (1139±220 U/L) at 48 h and 14 days (p<0.05, p<0.05, respectively). γ-GT levels of the HD group was 4.8±0.4 U/L compared to the Control group value of 0.9±0.2 U/L (p<0.05). Taking all factors into consideration, Croton membranaceus ingestion does not produce general acute toxicity. However, its creatinine kinase lowering ability could be explored.

Effects of Astragalus membranaceus on growth performance, carcass characteristics, and antioxidant status of broiler chickens

An experiment was conducted using 720 one-day-old Arbor Acres broiler chickens to evaluate the effects of Astragalus membranaceus root powder (AMP), Astragalus polysaccharides (APS) on growth performance, carcass characteristics, and antioxidant enzymes, and metabolites of blood and liver in broiler chickens. The six dietary treatments included a control that was a corn–soybean meal basal diet; basal diet supplemented with 120 mg/kg antibiotic; 350 mg/kg APS; or 5000, 10,000, or 15,000 mg/kg diet of AMP. Supplementation of 10,000 mg/kg AMP increased average daily gain and feed conversion rate of broilers in grower period (22–42 d) and over the entire experiment compared to basic diet. Responses of antioxidant status to dietary APS and AMP varied depending on the age of the broilers. Beneficial effects of AMP on growth and feed utilization of broilers could be obtained by inclusion of AMP at the rate of 10,000 mg/kg diet.

Antioxidant and Anti-diabetes Activities of Methanolic Extract and Fractions of Astragalus membranaceus Roots

The potential biological activities of methanol extract and 5 fractions (hexane, CH₂Cl₂, EtOAc, BuOH and water) from roots of Astragalus membranaceus were examined by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, hydroxyl radical (·OH) scavenging activity, reducing power assays, lipid peroxidation inhibitory activity, α-amylase and α-glucosidase inhibition assays. The EtOAc fraction showed high DPPH free radical scavenging activity (EC??=170.34 ㎍/㎖), hydroxyl radical scavenging activity (EC??=32.14 ㎍/㎖), lipid peroxidation inhibitory activity (EC??=52.46 ㎍/㎖) and a concentration dependence, with OD value ranging from 0.234 to 0.345 0.1 to 0.5 ㎎/㎖), for reducing power. The EtOAc fraction has the highest total phenolic content (142.13 Gal μg/mg) and the CH2Cl2 fraction has the highest flavonoid content (71.63 Que ㎍/㎎). Meanwhile, hexane and EtOAc showed certain α-amylase and α-glucosidase inhibition activities. These results suggest that the methanol extract and fractions from Astragalus membranaceus root have significant antioxidant and anti-diabetes activities, which could be used as a potential source of pharmaceutical materials.

Enhancement of non-specific immune response in sea cucumber ( Apostichopus japonicus) by Astragalus membranaceus and its polysaccharides

In this study, the immunostimulatory effect of oral administration of different preparations (conventional fine powder [CP] and superfine powder [SP]) of Astragalus membranaceus root or its polysaccharides (APS) in sea cucumber ( Apostichopus japonicus) was investigated. Sea cucumbers with an average initial weight of 49.3 ± 5.65 g were fed with a diet containing 3% CP or SP or 0.3% APS over a period of 60 days. The non-specific humoral (phenoloxidase, lysozyme and agglutination titer) and cellular (phagocytic capacity and reactive oxygen species) responses were determined and compared with controls (no supplement) after 20, 40 and 60 days of feeding. Variation in the levels of responses was evident among different supplements. SP and APS significantly enhanced most of the immune parameters tested. Among the humoral responses, lysozyme activity significantly increased after feeding with SP-supplemented diet for 20, 40 or 60 days. Furthermore, lectin titer showed significant enhancement after 20 and 60 days of feeding with APS-supplemented diet. Significant increase in the production of reactive oxygen species was evident for all three supplements after 20 days of feeding, but no significant change in serum phenoloxidase activity was observed for any of the three supplements over the three different periods. Overall, significant modulation of the cellular responses was only noticed after 20 days of feeding with SP- or APS-supplemented diet. After 60 days, these two groups also exhibited a decrease in the cumulative symptom rates compared to the controls when challenged with Vibrio splendidus. These results indicated that dietary intake containing A. membranaceus root or its polysaccharides could enhance the immune responses of A. japonicus and improve its resistance to infection by V. splendidus.

Saponin fraction from Astragalus membranaceus roots protects mice against polymicrobial sepsis induced by cecal ligation and puncture by inhibiting inflammation and upregulating protein C pathway

Sepsis remains the leading cause of death in intensive care units. Uncontrolled systemic inflammation and an impaired protein C pathway are two important contributors to sepsis pathophysiology. Based on the beneficial effects of the saponin fraction from Astragalus membranaceus roots (SAM) against inflammation, liver dysfunction, and endothelium injury, we investigated the potential protective roles and underlying mechanisms of SAM on polymicrobial sepsis induced by cecal ligation and puncture (CLP) in mice. SAM, orally administered 1 h before and after CLP, significantly elevated the survival rate of mice. At 96 h after CLP operation, all mice in the model group died, whereas 33.3% of mice in the SAM (400 mg/kg)-treated group survived. SAM attenuated both inflammatory factors and their abilities to induce tissue dysfunction, which was mainly evidenced by decreased infiltration of polymorphonuclear leukocytes, tissue edema, and lung wet-to-dry weight ratio, lowered levels of myeloperoxidase (MPO), nitric oxide (NO), lactate dehydrogenase (LDH), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) in serum, as well as downregulated expressions of iNOS and IL-1beta mRNA in livers. Furthermore, we addressed the effects of SAM on the protein C (PC) pathway, closely linked with sepsis. In CLP-induced septic mice, SAM elevated the impaired expression of PC mRNA in livers. In vitro, SAM reversed the decreased expressions of thrombomodulin (TM) and endothelial PC receptor (EPCR) mRNA induced by lipopolysaccharide (LPS) in endothelial cells. These findings suggest that SAM is able to restore the impaired protein C pathway. Taken together, the current study demonstrates that SAM has protective effects on polymicrobial sepsis in mice. The mechanisms of action involve anti-inflammation and upregulation of the PC pathway.

The evaluation of selected ghanaian medicinal plants for cytotoxic activites

Cancer is still responsible for many deaths worldwide. Therefore, the need for an effective management, treatment and cure of cancer is undoubtedly crucial. In Ghana, several plants or herbal products are used by traditional healers for the management and/or the treatment of various cancers. However, the efficacies of these plant products as anticancer agents are often ill defined. In this study, the methanolic extracts of ten plant species were evaluated for cytotoxicity against three human cancer cell lines, DLD- 1, MCF-7 and M14, using the MTT assay. Extracts of Adenia lobata root, Clerodendrum capitatum leaves, Garcinia kola stem bark, Plumbago zeylanica leaves and Vernonia conferta root, showed relatively low cytotoxic activities while extracts of Ficus asperifolia leaves, Paullinia pinnata root and Thonningia sanguinea root exhibited moderate activity (IC50 values 40 – 55&#956;g/ml against at least one of the three cell lines). Croton membranaceus root extract exhibited markedly higher cytotoxic activities, particularly against the DLD-1 and MCF-7 cells (IC50 = 16.0 and 17.4&#956;g/ml respectively), while Zanthoxylum xanthoxyloides bark extract was 2-3 fold more active against DLD-1 cells (IC50 = 16&#956;g/ml), than against the other cell lines. These results lend some support for the use of these species in traditional medicines for the treatment of cancer, especially for C. membranaceus and Z. xanthoxyloides.Journal of Science & Technology (Ghana) Vol. 27 (2) 2007: pp. 16-22

Merit of Astragalus polysaccharide in the improvement of early diabetic nephropathy with an effect on mRNA expressions of NF-κB and IκB in renal cortex of streptozotoxin-induced diabetic rats

Aim of study Diabetic nephropathy (DN) is the leading cause of the end-stage failure of kidney, but the efficacy of currently available strategies for the prevention of DN remains poor. An activation of the transcription factor, nuclear factor-κB (NF-κB), has been suggested to be a key step in the pathogenesis of DN. In the present study, we investigated the effect of Astragalus polysaccharide (APS), an aqueous extract from the Astragalus membranaceus roots, on gene expressions of NF-κB and an inhibitory protein of nuclear factor-κB (IκB) in experimental DN induced by streptozotocin in male Sprague-Dawley rats. Materials and Method Rats with DN were treated with APS (1 g/kg p.o.) or benazepril (1.5 mg/kg p.o.), an angiotensin-converting enzyme inhibitor, using as positive control. The biochemical parameters such as blood glucose, plasma lipid and microalbuminuria were measured. Also, the mRNA level of NF-κB or IκB in renal cortex was determined using reverse transcription-polymerase chain reaction. Results Eight weeks after the treatment, symptoms including shineless, bristly hair, polyuria, polydipsia, lethargy, physical inactivity, loss of body weight, kyphosis and decubitus position were ameliorated by APS. The levels of blood glucose, plasma lipid and microalbuminuria were lowered in APS-treated rats compared with control rats. The ratio of kidney weight over body weight was reduced and the renal function was improved after APS treatment. The mRNA level of NF-κB in renal cortex was decreased and IκB mRNA expression was raised by APS. These results suggest that APS has prophylactic and therapeutic effects on the progress of DN; Conclusions therefore, APS is helpful for the prevention and/or treatment of DN at early stage.

Insulin Sensitization and Anti‐obesity Effects of Astragalus Polysaccharide on High Fat Diet‐fed C57BL/6J Mice

Insulin resistance and obesity are two critical factors in type 2 diabetes (T2DM). We recently discovered a natural anti-diabetic substance, Astragalus polysaccharide (APS), which is a component of an aqueous extract of Astragalus membranaceus roots. Here we examine the underlying mechanism of the anti-diabetic action of APS. This study characterizes a insulin resistant mouse model treated with high-fat diet. Eight-week-old female C57BL/6J mice were fed a high fat diet (HFD) and treated with APS (700 mg/kg/day) for 12 weeks. Age and sex-matched, normal diet-fed controls were similarly treated. APS intervention significantly decreased the tendency of body weights to increase of HFD-fed C57BL/6J mice in weeks 8–12. After APS treatment, the HFD-fed mice showed a significant increase in insulin sensitivity. HFD-fed showed significantly increased levels and activities of PTP1B in skeletal muscle (1.7- and 1.9-fold, respectively) and liver (1.6- and 1.8-fold, respectively), thus diminishing insulin signaling in the target tissues. We found that the decreased insulin-stimulated GLUT4 translocation in muscles from insulin resistant mice were reversed after APS treatment. These effects were associated with significant decreases in high PTP1B levels and activities, respectively, in skeletal muscles and livers of APS treated mice. The non HFD diet-fed mice treated with APS did not significantly change PTP1B activities and levels, and blood insulin levels in normal diet-fed mice as well. These data suggest that APS enables insulin-sensitizing and anti-obesity effects at least in part by decreasing the elevated expression and activity of PTP1B in the skeletal muscles and livers from insulin resistant mice. (supported by NSFC grant No.30370673)

Application of 3‘ Untranslated Region (UTR) Sequence-Based Amplified Polymorphism Analysis in the Rapid Authentication of Radix astragali

Radix astragali (root of Astragalus membranaceus) is an important traditional Chinese medicine. It has been used as a tonic herb for thousands of years in China. The water extract of the roots has a wide range of immunopotentiating effects and has been proven to be efficacious as an adjunct cancer therapy. Authentication of the herbal plant is routinely required for general practice in the field of herbal medicine. To facilitate rapid identification of numerous varieties of Radix astragali that are circulating on the herb markets, a rapid molecular genetic method, named 3' untranslated region (3' UTR) sequence-based amplified polymorphism (UAP), has been developed. A cDNA library was first built from transcripts of an authentic A. membranaceus species. Several cDNA clones specific to A. membranaceus were identified through subtractive hybridization of the A. membranaceus cDNA library with Arabidopsis total cellular RNA. On the basis of these cDNA sequences of the 3' untranslated region (3' UTR) of selected cDNA clones, a Polymerase Chain Reaction (PCR) was performed on genomic DNAs of the dry roots of several putative A. membranaceus. PCR fragment length polymorphism was found between A. membranaceus and its relatives. By using this method, it was possible to differentiate the authentic A. membranaceus root from those putative ones obtained from herbal medicine markets. To the authors' knowledge, this is the first paper applying UAP in the authentication of traditional Chinese medicine plants.

Hypoglycemic effect of Astragalus polysaccharide and its effect on PTP1B1

To examine the effects of Astragalus polysaccharide (APS), a component of an aqueous extract of Astragalus membranaceus roots, on protein tyrosine phosphatase 1B (PTP1B), a negative regulator of insulin-receptor (IR) signal transduction, and its potential role in the amelioration of insulin resistance. Ten-week-old fat-fed streptozotocin (STZ)-treated rats, an animal model of type II diabetes mellitus (TIIDM), were treated with APS (400 mg/kg p.o.) for 5 weeks. Insulin sensitivity was identified by the insulin-tolerance test. Further analyses on the possible changes in insulin signaling occurring in skeletal muscle and liver were performed by immunoprecipitation or Western blotting. PTP1B activity was measured by an assay kit. The diabetic rats responded to APS with a significant decrease in body weight, plasma glucose, and improved insulin sensitivity. The activity and expression of PTP1B were elevated in the skeletal muscle and liver of TIIDM rats. Thus the insulin signaling in target tissues was diminished. APS reduced both PTP1B protein level and activity in the muscle, but not in the liver of TIIDM rats. Insulin-induced tyrosine phosphorylation of the IR beta-subunit and insulin receptor substrate-1 (IRS-1) were increased in the muscle, but not in the liver of APS-treated TIIDM rats. There was no change in the activity or expression of PTP1B in APS-treated normal rats, and blood insulin levels did not change in TIIDM rats after treatment with APS. APS enables insulin-sensitizing and hypoglycemic activity at least in part by decreasing the elevated expression and activity of PTP1B in the skeletal muscles of TIIDM rats.