Legume nodulation and nitrogen fixation require interaction of DnaJ-like protein and lipid transfer protein.

The lipid transport protein (LTP) product of the AsE246 gene of Chinese milk vetch (Astragalus sinicus) contributes to the transport of plant-synthesized lipids to the symbiosome membranes (SMs) that are required for nodule organogenesis in this legume. However, the mechanisms used by nodule-specific LTPs remain unknown. In this study, a functional protein in the DnaJ-like family, designated AsDJL1, was identified and shown to interact with AsE246. Immunofluorescence showed that AsDJL1 was expressed in infection threads (ITs) and in nodule cells and that it co-localized with rhizobium, and an immunoelectron microscopy assay localized the protein to SMs. Via co-transformation into Nicotiana benthamiana cells, AsDJL1 and AsE246 displayed subcellular co-localization in the cells of this heterologous host. Co-immunoprecipitation assays confirmed that AsDJL1 interacted with AsE246 in nodules. The essential interacting region of AsDJL1 was determined to be the zinc finger domain at its C-terminus. Chinese milk vetch plants transfected with AsDJL1-RNAi had significantly decreased numbers of ITs, nodule primordia and nodules as well as reduced (by 83%) nodule nitrogenase activity compared with the controls. By contrast, AsDJL1 overexpression led to increased nodule fresh weight and nitrogenase activity. RNAi-AsDJL1 also significantly affected the abundance of lipids, especially digalactosyldiacylglycerol, in early-infected roots and transgenic nodules. Taken together, the results of this study provide insights into the symbiotic functions of AsDJL1, which may participate in lipid transport to SMs and play an essential role in rhizobial infection and nodule organogenesis.

Astragalus Polysaccharide Mediates Immunomodulatory Effects on Crosstalk between Human Peripheral Blood Mononuclear Cells and Ovarian Cancer Cell Line.

Astragalus polysaccharide (APS) is a functional component of Astragalus membranaceus with antitumor and immunomodulatory properties. This study evaluated the effect of APS on the peripheral blood mononuclear cell (PBMC) proliferation, cytokine secretion, and regulatory T cell (Treg) induction in an in vitro coculture model of human PBMCs and A2780 human ovarian cancer cells. PBMC proliferation and Treg frequency were measured by flow cytometry. Cytokine levels were assessed by enzyme-linked immunosorbent assay. APS significantly enhanced the PBMC proliferation, reduced Treg frequency, decreased anti-inflammatory cytokines including interleukin [IL]-10, transforming growth factor beta (TGF-ß), and vascular endothelial growth factor-A (VEGF-A), and increased the pro-inflammatory cytokine IL-6. These findings suggest that APS may be an effective immunomodulatory supplement for cancer therapy, particularly for ovarian cancer by enhancing antitumor immune responses.

[Mechanism of Astragali Radix-Puerariae Lobatae Radix combination in regulating type 2 diabetes mellitus through AMPK signaling pathway: based on network pharmacology and experimental verification].

This study aims to explore the mechanism of Astragali Radix-Puerariae Lobatae Radix(AP) combination in the treatment of type 2 diabetes mellitus(T2 DM) based on network pharmacology and experiment. The effective components and targets of the pair were retrieved from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP) and targets of T2 DM from each disease database. On this basis, the common targets of the medicinals and the disease were screened out. The protein-protein interaction(PPI) network was established based on STRING. Then Cytoscape 3.7.1 was employed for visualization of the common targets and the network topology analysis of key targets, followed by Gene Ontology(GO) term enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment of core targets by DAVID. Thereby, the possible molecular mechanism was unveiled. High-fat diet was combined with streptozotocin(STZ, injected into tail vein) for T2 DM rat modeling. Rats were classified into the normal group, model group, positive control group(metformin hydrochloride), AP high-dose, medium-dose, and low-dose groups. After 4 weeks of intragastric administration, serum fasting blood glucose(FBG), fasting insulin(FINS), aspartate aminotransferase(AST), alanine aminotransferase(ALT), triglyceride(TG), total cholesterol(TC), low-density lipoprotein cholesterol(LDL-C), high-density lipoprotein cholesterol(HDL-C), interleukin(IL)-6, and tumor necrosis factor(TNF)-α of rats in each group were measured. The expression of insulin receptor substrate-2(IRS-2), adenosine monophosphate-activated protein kinase(AMPK), phosphorylated AMPK(p-AMPK), glucose 6 phosphatase(G6 Pase), and phosphoenolpyruvate carboxy kinase(Pepck) in rat liver was detected by Western blot. A total of 131 core targets of the combination in the treatment of T2 DM were screened out, among which protein kinase B(AKT) 1, mitogen-activated protein kinase(MAPK) 1, TNF-α, IL-6 were more critical. KEGG enrichment analysis suggested that the combination decreased blood glucose mainly through PI3 K/AKT signaling pathway, AMPK signaling pathway, TNF signaling pathway, and MAPK signaling pathway. The levels of FBG and FINS were lower and the glycogen level was higher in the AP high-dose and medium-dose groups than in the model group. The levels of AST, ALT, TG, and LDL-C in the three AP groups and the level of TC in AP high-dose and low-dose groups decreased compared with those in the model group. Levels of IL-6 and TNF-α were lower in AP high-dose and medium-dose groups than in the model group. The expression of IRS-2, AMPK, and p-AMPK was higher and that of G6 Pase and Pepck was lower in AP high-dose group than in the model group. Thus, the combination had multi-component, multi-target, and multi-pathway characteristics in the treatment of T2 DM. It may regulate AMPK signaling pathway through IL-6 and TNF-α to influence insulin resistance, glycogen synthesis, gluconeogenesis, islet ß cell transport, and inflammatory response, thereby exerting therapeutic effect on T2 DM.

Selenium nanoparticles coupling with Astragalus Polysaccharides exert their cytotoxicities in MCF-7 cells by inhibiting autophagy and promoting apoptosis.

BACKGROUND: Astragalus Polysaccharides (APS) had been reported to exhibit antitumor activities. Given that nanoparticles possessed unique advantages in cancer treatment, APS was used as the modifier to prepare gold, silver and selenium nanoparticles (APS-Au, APS-Ag and APS-Se NPs) in the present study. METHODS: The three nanoparticles were synthesized via a green approach and characterized by DLS, TEM, XRD, FT-IR and UV-Vis. The inhibitory effects of these nanoparticles on various tumor cells proliferation were examined by MTT assay in vitro. Reactive oxygen species (ROS), mitochondrial membrane potential (MMP) and the expression of apoptosis and autophagy-related proteins were also detected. RESULTS: Among these, APS-Se NPs displayed the most potent antitumor activities against MCF-7 cells in vitro. Flow cytometric analysis suggested that after cells were exposed to elevated concentrations of APS-Se NPs (10, 20 and 40 µmol/L), the rate of apoptosis was increasing (16.63 ± 0.89, 38.60 ± 3.46 and 44.38 ± 2.62%, respectively). Further analysis by immunofluorescence revealed an increase in intracellular ROS and a loss of MMP. This was accompanied by increased LC3-I to LC3-II conversion. Also, western blot analysis demonstrated that the ratios of Bax/Bcl-2 and cleaved caspase9/caspase 9 rose, and LC3-II and p62 protein levels increased. The addition of chloroquine, an inhibitor of autophagy, further enhanced protein expression of p62 and LC3-II. CONCLUSION: APS-Se NPs exerted their cytotoxic activity in MCF-7 cells by blocking autophagy and facilitating mitochondrial pathway-mediated apoptosis.

Combining the Anticancer and Immunomodulatory Effects of Astragalus and Shiitake as an Integrated Therapeutic Approach.

Astragalus root (Huang Qi) and Shiitake mushrooms (Lentinus edodes) are both considered medicinal foods and are frequently used in traditional Chinese medicine due to their anticancer and immunomodulating properties. Here, the scientific literatures describing evidence for the anticancer and immunogenic properties of Shiitake and Astragalus were reviewed. Based on our experimental data, the potential to develop medicinal food with combined bioactivities was assessed using Shiitake mushrooms grown over Astragalus beds in a proprietary manufacturing process, as a novel cancer prevention approach. Notably, our data suggest that this new manufacturing process can result in transfer and increased bioavailability of Astragalus polysaccharides with therapeutic potential into edible Shiitake. Further research efforts are required to validate the therapeutic potential of this new Hengshan Astragalus Shiitake medicinal food.

Dynamic content changes of cordycepin and adenosine and transcriptome in Cordyceps kyushuensis Kob at different fermentation stages.

20% (w/w) Astragali radix was added to the rice medium to cultivate C. kyushuensis Kob. The fermentation product was collected at mycelium stage, coloring stage, stromata-forming initial stage and fruiting body stage of C. kyushuensis Kob. The dynamic content changes of cordycepin and adenosine were detected at different fermentation stages. In the rice medium with Astragalus radix, both cordycepin and adenosine reached the highest content value on the 30th day of fermentation, 17.31 mg/g and 0.94 mg/g, respectively, which were 8.6 times and 2.0 times of that in rice medium at the same stage. At the same time, transcriptomics technology was used to analyze C. kyushuensis Kob during these four periods.

Astragalus root extract improved average daily gain, immunity, antioxidant status and ruminal microbiota of early weaned yak calves.

BACKGROUND: Early weaning in yak calves is being attempted to improve yak reproduction rate. However, this has to be done with caution because of the high mortality rate of calves due to the lack of nutrients and the harsh environmental conditions. Twenty-four weaned male yak calves were used in a 60 day feeding trial in which astragalus root extract (ARE) was supplemented. They were assigned randomly to one of four dietary treatments (n = six per treatment) that differed in ARE level: 0 g kg-1 (control), ARE0 ; 20 g kg-1 , ARE20 ; 50 g kg-1 , ARE50; and 80 g kg-1 dry matter intake (DMI), ARE80 . RESULTS: Final bodyweight and average daily gain (ADG) were significantly higher and the DMI/ADG ratio was significantly lower in calves with ARE supplementation than control (ARE0 ) calves. Ruminal concentrations of acetate and propionate and serum concentration of superoxide dismutase in ARE80 calves were higher than in the other groups and serum concentration of insulin was higher in ARE80 calves than in ARE20 calves. Serum immunoglobulin G (IgG) and interleukin-2 (IL-2) concentrations in ARE-fed calves were higher than in controls. Serum tumor necrosis factor (TNF-α) concentration was higher in ARE50 and ARE80 groups than ARE0 calves and serum interleukin-6 (IL-6) concentration was higher in ARE80 than in ARE0 calves. Serum immunoglobulin A (IgA), IgG and immunoglobulin M (IgM) concentrations increased with age in ARE-fed calves. ARE supplementation increased the abundance of fiber degrading bacteria. CONCLUSION: ARE at a dosage of 5% to 8% DMI can be supplemented to early weaned yak calves to improve growth performance, antioxidant capacity and immunity. © 2020 Society of Chemical Industry.

Comparison of Platelet Rich Plasma and Prolotherapy in the Management of Osteochondral Lesions of the Talus: A Retrospective Cohort Study.

BACKGROUND Osteochondral lesions of talus (OLT) are among the most common ankle problems. Platelet-rich plasma (PRP) and prolotherapy (PrT) are 2 successful injection-based techniques for treatment of chronic musculoskeletal problems. The aim of the present study was to compare PRP and PrT injections for the management of OLT. MATERIAL AND METHODS This was a retrospective cohort study of 49 patients with OLT symptoms of more than 6 months who had been refractory to 3 months of treatment using conservative methods. The patients were divided into 2 groups: PrT injections (PrT group, n=27) or PRP injections (PRP group, n=22). The patients were given 3 injections of 4 mL solution into periarticular and intra-articular ankle joint spaces. After treatment, patients were evaluated via Visual Analogue Scale (VAS), American Orthopedic Foot and Ankle Society Score (AOFAS), and Ankle Osteoarthritis Scale (AOS) at baseline and 21-, 90-, 180-, and 360-day follow-up periods. RESULTS Both PRP and PrT treatments resulted in greater improvement in pain and ankle functions at follow-up periods extending to 1 year (P<0.001) and there was no difference between the groups for the outcomes at follow-up periods (P>0.05). Excellent or good outcomes were reported by 88.8% of the patients in PrT group and 90.9% of the patients in PRP group. CONCLUSIONS Both PRP and PrT are efficient and safe methods in treatment of OLT. PrT offers advantages of less cost and minimal invasiveness.

The Effects of Astragalus Polysaccharide on Bone Marrow-Derived Mesenchymal Stem Cell Proliferation and Morphology Induced by A549 Lung Cancer Cells.

BACKGROUND The tumor microenvironment in lung cancer plays an important role in tumor progression and metastasis. Bone marrow-derived mesenchymal stem cells (MSCs) co-cultured with A549 lung cancer cells show changes in morphology, increase cell proliferation, and cell migration. This study aimed to investigate the effects of Astragalus polysaccharide (APS), a traditional Chinese herbal medicine, on the changes induced in bone marrow-derived MSCs by A549 lung cancer cells in vitro. MATERIAL AND METHODS Bone marrow-derived MSCs were co-cultured with A549 cells (Co-BMSCs). Co-cultured bone marrow-derived MSCs and A549 cells treated with 50 µg/ml of APS (Co-BMSCs + APS) were compared with untreated Co-BMSCs. Cell proliferation was measured using the cell counting kit-8 (CCK-8) assay. Flow cytometry evaluated the cell cycle. Microarray assays for mRNA expression and Western blot for protein expression were used. RESULTS Compared with untreated Co-BMSCs, APS treatment of Co-BMSCs improved cell morphology, reduced cell proliferation, and inhibited cell cycle arrest. The mitogen-activated protein kinase (MAPK)/nuclear factor-kappa B (NF-kappaB) pathway, TP53, caspase-3, acetylated H4K5, acetylated H4K8, and acetylated H3K9 were involved in the regulatory process. CONCLUSIONS APS treatment reduced cell proliferation and morphological changes in bone marrow-derived MSCs that were co-cultured with A549 lung cancer cells in vitro.

Fe3O4@ Astragalus Polysaccharide Core-Shell Nanoparticles for Iron Deficiency Anemia Therapy and Magnetic Resonance Imaging in Vivo.

Iron deficiency anemia (IDA) is a common nutritional disease suffered by 1 billion people. To develop a new drug which avoids the side effects of traditional oral iron supplementation for IDA treatment, we have designed Fe3O4@ Astragalus polysaccharide core-shell nanoparticles (Fe3O4@APS NPs) and demonstrated them to be an efficient therapeutic drug for IDA treatment in vivo. The Fe3O4@APS NPs have been successfully synthesized with good water solubility and stability, especially in imitated digestion. Cytotoxicity assessment in cells and pathological tests in mice justify their good biocompatibility and low toxicity. The IDA treatment in rats shows that they have efficient therapeutic effect, which is contributed to both the iron element supplement from Fe3O4 and the APS-stimulated hematopoietic cell generation. Moreover, the superparamagnetic Fe3O4@APS NPs are capable for use as a magnetic resonance imaging contrast agent. This study presents the possibility of nanocomposites involving purified natural products from Chinese herb medicine for biomedical applications.

Mesorhizobium huakuii HtpG Interaction with nsLTP AsE246 Is Required for Symbiotic Nitrogen Fixation.

Plant nonspecific lipid transfer proteins (nsLTPs) are involved in a number of biological processes including root nodule symbiosis. However, the role of nsLTPs in legume-rhizobium symbiosis remains poorly understood, and no rhizobia proteins that interact with nsLTPs have been reported to date. In this study, we used a bacteria two-hybrid system and identified the high temperature protein G (HtpG) from Mesorhizobium huakuii that interacts with the nsLTP AsE246. The interaction between HtpG and AsE246 was confirmed by far-Western blotting and bimolecular fluorescence complementation. Our results indicated that the heat shock protein 90 (HSP90) domain of HtpG mediates the HtpG-AsE246 interaction. Immunofluorescence assay showed that HtpG was colocalized with AsE246 in infected nodule cells and symbiosome membranes. Expression of the htpG gene was relatively higher in young nodules and was highly expressed in the infection zones. Further investigation showed that htpG expression affects lipid abundance and profiles in root nodules and plays an essential role in nodule development and nitrogen fixation. Our findings provide further insights into the functional mechanisms behind the transport of symbiosome lipids via nsLTPs in root nodules.

Benefit of an association of an antioxidative substrate and a traditional chinese medicine on telomere elongation.

Telomere shortening is involved in age-related disorders, such as cancer and cardiovascular diseases. Recently, telomerase re-activation strategies have been proposed to counteract telomere shortening and its consequences. Here, we investigated the benefit of dietary supplementation with a mix of S-adenosyl-methionine (SAMe) and a polysaccharide extract of Astragalus (APS) on telomere length of circulating lymphocytes of healthy volunteers. Blood lymphocytes of a cohort of 26 healthy volunteers who were administrated the mix of SAMe and APS in a food supplement for one year were collected. In vitro treatment of blood lymphocytes of healthy volunteers with the mix was also performed. A cohort of 150 healthy volunteers was used as a control. Telomere length was measured by Q-FISH. The micronucleus assay was performed to detect genotoxicity of the mix. The telomeres of circulating lymphocytes of the cohort of 26 donors supplemented with the mix were significantly longer than those of matched controls (p < 10-4). This elongation was essentially observed in the lymphocytes of older donors. Similarly, in vitro treatment of circulating lymphocytes with the mix significantly increased telomere length and decrease the proportion of cells with short telomeres. Here, we observed an increase in telomere length after in vivo and in vitro administration of a mix with SAMe and APS.  The benefit of dietary supplementation with this mix opens a new horizon for the battle against aging and could be used in the treatment of chronic age-related disorders.

Astragalus Polysaccharide Inhibits Ionizing Radiation-Induced Bystander Effects by Regulating MAPK/NF-kB Signaling Pathway in Bone Mesenchymal Stem Cells (BMSCs).

BACKGROUND This study investigated the effect of Astragalus polysaccharides (APS) on radiation-induced bystander effects (RIBE) in human bone mesenchymal stem cells (BMSCs) induced by irradiated A549 cells. MATERIAL AND METHODS A549 cells were irradiated with 2 Gy X-rays to obtain conditioned medium. BMSCs were incubated with the conditioned medium or APS. The levels of reactive oxygen species (ROS) and TGF-ß were detected by ELISA. Cell survival, genomic instability, and DNA damages were detected by CCK-8 assay, colony formation assay, the micronucleus test and immunofluorescence assay, respectively. The protein and phosphorylation protein expression of p38, c-Jun N-terminal kinase (JNK), extracellular regulated protein kinase (ERK1/2), P65, and cyclooxygenase-2 (COX-2) in bystander effect cells were detected by Western blot. RESULTS The expression of COX-2 and ROS increased following stimulation with conditioned medium; this effect was inhibited by pre-exposing the cells to APS. BMSCs growth and colony formation rate decreased following stimulation with conditioned medium; this effect was suppressed by pre-exposing the cells to APS. In addition, the micronucleus rate and 53BP1 foci number increased after treatment with conditioned medium; this increase in BMSCs was inhibited by APS. The levels of phosphorylated p38, JNK, ERK1/2, NF-κB P65, and COX-2 proteins were increased by conditioned medium but were decreased by pre-treatment with APS. CONCLUSIONS RIBE in BMSCs induced by the irradiated A549 was mediated by the ROS in the conditioned medium and might be related to MAPK/NF-κB signal pathways in BMSCs. APS may block RIBE through regulating the MAPK/NF-κB pathway.

Secondary Metabolites from Astragalus lycius and Their Cytotoxic Activities.

Eight known secondary metabolites were isolated from the methanolic extract of the whole plant of Astragalus lycius Boiss. They were identified as 5,5'-dihydoxy-3'-methoxy-isoflavone-7-0-ß-D-glucoside (1), genistin (2), sissotrin (3), 5,4'-dimethoxy-isoflavone-7-0-ß-D-glucopyranoside (4), (7S,8R)-5-methoxydehydrodiconiferyl alcohol-4-0-ß-D-glucopyranoside (5), 4-0-lariciresinol-glucoside (6), 2-phenylethyl-ß-D-glucopyranoside (7) and ß-sitosterol-3-O-ß-D-glucopyranoside (8) by spectroscopic methods including (1)H- and (13)C-NMR and HR-MS experiments, and by comparison with literature values. Compounds 1-7 are reported for the first time from Astragalus taxa. All of the compounds were tested for their cytotoxic activities against a number of cancer cell lines. Among them, only 6 exhibited significant activity against human colon carcinoma (HT-29) at 2.69 µM concentration.

A JAZ Protein in Astragalus sinicus Interacts with a Leghemoglobin through the TIFY Domain and Is Involved in Nodule Development and Nitrogen Fixation.

Leghemoglobins (Lbs) play an important role in legumes-rhizobia symbiosis. Lbs bind O2 and protect nitrogenase activity from damage by O2 in nodules, therefore, they are regarded as a marker of active nitrogen fixation in nodules. Additionally, Lbs are involved in the nitric oxide (NO) signaling pathway, acting as a NO scavenger during nodule development and nitrogen fixation. However, regulators responsible for Lb expression and modulation of Lb activity have not been characterized. In our previous work, a Jasmonate-Zim-domain (JAZ) protein interacting with a Lb (AsB2510) in Astragalus sinicus was identified and designated AsJAZ1. In this study, the interaction between AsJAZ1 and AsB2510 was verified using a yeast two-hybrid system and in vitro Glutathione S-transferase (GST) pull-down assays, resulting in identification of the interaction domain as a TIFY (previously known as zinc-finger protein expressed in inflorescence meristem, ZIM) domain. TIFY domain is named after the most conserved amino acids within the domain. Bimolecular fluorescence complementation (BiFC) was used to confirm the interaction between AsJAZ1 and AsB2510 in tobacco cells, demonstrating that AsJAZ1-AsB2510 interaction was localized to the cell membrane and cytoplasm. Furthermore, the expression patterns and the symbiotic phenotypes of AsJAZ1 were investigated. Knockdown of AsJAZ1 expression via RNA interference led to decreased number of nodules, abnormal development of bacteroids, accumulation of poly-x-hydroxybutyrate (PHB) and loss of nitrogenase activity. Taken together, our results suggest that AsJAZ1 interacts with AsB2510 and participates in nodule development and nitrogen fixation. Our results provide novel insights into the functions of Lbs or JAZ proteins during legume-rhizobia symbiosis.

Astragalus polysaccharide attenuates lipopolysaccharide-induced inflammatory responses in microglial cells: regulation of protein kinase B and nuclear factor-κB signaling.

OBJECTIVES AND DESIGN: Microglia play an important role in immune and inflammatory responses in the central nervous system. Astragalus polysaccharide (APS) has been reported as an immune stimulant for various inflammation-associated diseases in vivo. The present study investigated the effects of APS on lipopolysaccharide-stimulated inflammatory responses in microglial cells. MATERIALS AND METHODS: Cultured BV2 microglial cells were pre-treated with APS (0-200 µg/ml) prior to lipopolysaccharide (50 ng/ml) stimulation. The production of proinflammatory mediators including inducible nitric oxide synthase (iNOS)/nitric oxide (NO), cyclooxygenase-2 (COX-2)/prostaglandin E (PGE2), tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) were evaluated. RESULTS: APS dose-dependently reduced lipopolysaccharide stimulated nitric oxide and PGE2 production, as well as iNOS and cyclooxygenase-2 gene expression. It also attenuated proinflammatory cytokines IL-1ß and TNF-α generation. In addition, APS inhibited nuclear factor-κB translocation by blockade of IκB degradation and suppressed protein kinase B phosphorylation in lipopolysaccharide-stimulated cells. CONCLUSIONS: The inhibitory effects of APS on lipopolysaccharide-stimulated inflammatory mediator production in microglia are associated with suppression of nuclear factor-κB and protein kinase B signaling pathways. APS may offer therapeutic potential for treating inflammatory and neurodegenerative diseases accompanied with microglial activation.

Astragalus Polysaccharide Inhibits Autophagy and Apoptosis from Peroxide-Induced Injury in C2C12 Myoblasts.

The aim is to study the effects and underlying mechanisms of astragalus polysaccharide (APS) on the peroxide-induced injury in C2C12 myoblasts in vitro. Cell viability in the presence or absence of APS was detected by the methyl thiazolyl tetrazolium colorimetric assay. The autophagosomes were observed by electron microscopy to examine the influence of APS on autophagy caused by H2O2 in C2C12 cells, and the percentage of apoptosis cells was measured by flow cytometry. To further confirm the effect of H2O2 on C2C12 cells, the protein expression of LC3 and RARP, which are the markers of autophagy and apoptosis, respectively, was analyzed by Western blot, as well as the expression levels of p-p70S6K, p70S6K, Bcl-2, Bax, cyto-C, and Caspase-3, to reveal the underlying mechanisms. We observed multiple effects of APS on C2C12 functionality. APS treatment of C2C12 cells at 1 mg/mL reduced cell viability to less than 70 %, and analysis by electron microscopy revealed that APS also reduced the number of H2O2-induced autophagosome formation. Similarly, APS abated the H2O2-mediated increase in cell apoptosis, which was accompanied by the inhibition of LC3 II and RARP that are normally upregulated by H2O2. The expression of p-p70S6K and p70S6K, however, remained unchanged in C2C12 cells in the Control, H2O2 and H2O2 + APS groups. In addition, APS promoted the expression of protein Bcl-2 in H2O2-treated C2C12 cells, but did not change Bax, thus reducing the Bax/Bcl-2 ratio that in turn prevented the release of cytochrome c and the activation of caspase-3. APS inhibits the autophagy and apoptosis induced by peroxide injury in C2C12 myoblasts through two independent signaling pathways: the mTOR-independent pathway for the inhibition of autophagy, and the caspase-3-dependent pathway for the suppression of apoptosis.

A review of recent research progress on the astragalus genus.

Astragalus L., is one of the largest genuses of flowering plants in the Leguminosae family. Roots of A. membranaceus Bge. var. mongholicus (Bge.) Hsiao, A. membranaceus (Fisch.) Bge. and its processed products are listed in the China Pharmacopeia for "qi deficiency" syndrome treatment. However, more and more researches on other species of Astragalus have been conducted recently. We summarize the recent researches of Astragalus species in phytochemistry and pharmacology. More than 200 constituents, including saponins and flavonoids, obtained from 46 species of Astragalus genus were collected for this article. In pharmacological studies, crude extracts of Astragalus, as well as isolated constituents showed anti-inflammatory, immunostimulant, antioxidative, anti-cancer, antidiabetic, cardioprotective, hepatoprotective, and antiviral activities. The goal of this article is to provide an overview of chemical and pharmacological studies on the Astragalus species over the last 10 years, which could be of value to new drug or food supplement research and development.

Astragalus polysaccharide suppresses doxorubicin-induced cardiotoxicity by regulating the PI3k/Akt and p38MAPK pathways.

BACKGROUND: Doxorubicin, a potent chemotherapeutic agent, is associated with acute and chronic cardiotoxicity, which is cumulatively dose-dependent. Astragalus polysaccharide (APS), the extract of Astragalus membranaceus with strong antitumor and antiglomerulonephritis activity, can effectively alleviate inflammation. However, whether APS could ameliorate chemotherapy-induced cardiotoxicity is not understood. Here, we investigated the protective effects of APS on doxorubicin-induced cardiotoxicity and elucidated the underlying mechanisms of the protective effects of APS. METHODS: We analyzed myocardial injury in cancer patients who underwent doxorubicin chemotherapy and generated a doxorubicin-induced neonatal rat cardiomyocyte injury model and a mouse heart failure model. Echocardiography, reactive oxygen species (ROS) production, TUNEL, DNA laddering, and Western blotting were performed to observe cell survival, oxidative stress, and inflammatory signal pathways in cardiomyocytes. RESULTS: Treatment of patients with the chemotherapeutic drug doxorubicin led to heart dysfunction. Doxorubicin reduced cardiomyocyte viability and induced C57BL/6J mouse heart failure with concurrent elevated ROS generation and apoptosis, which, however, was attenuated by APS treatment. In addition, there was profound inhibition of p38MAPK and activation of Akt after APS treatment. CONCLUSIONS: These results demonstrate that APS could suppress oxidative stress and apoptosis, ameliorating doxorubicin-mediated cardiotoxicity by regulating the PI3k/Akt and p38MAPK pathways.

Roles of rhizobial symbionts in selenium hyperaccumulation in Astragalus (Fabaceae).

PREMISE OF THE STUDY: Are there dimensions of symbiotic root interactions that are overlooked because plant mineral nutrition is the foundation and, perhaps too often, the sole explanation through which we view these relationships? In this paper we investigate how the root nodule symbiosis in selenium (Se) hyperaccumulator and nonaccumulator Astragalus species influences plant selenium (Se) accumulation. METHODS: In greenhouse studies, Se was added to nodulated and nonnodulated hyperaccumulator and nonaccumulator Astragalus plants, followed by investigation of nitrogen (N)-Se relationships. Selenium speciation was also investigated, using x-ray microprobe analysis and liquid chromatography-mass spectrometry (LC-MS). KEY RESULTS: Nodulation enhanced biomass production and Se to S ratio in both hyperaccumulator and nonaccumulator plants. The hyperaccumulator contained more Se when nodulated, while the nonaccumulator contained less S when nodulated. Shoot [Se] was positively correlated with shoot N in Se-hyperaccumulator species, but not in nonhyperaccumulator species. The x-ray microprobe analysis showed that hyperaccumulators contain significantly higher amounts of organic Se than nonhyperaccumulators. LC-MS of A. bisulcatus leaves revealed that nodulated plants contained more γ-glutamyl-methylselenocysteine (γ-Glu-MeSeCys) than nonnodulated plants, while MeSeCys levels were similar. CONCLUSIONS: Root nodule mutualism positively affects Se hyperaccumulation in Astragalus. The microbial N supply particularly appears to contribute glutamate for the formation of γ-Glu-MeSeCys. Our results provide insight into the significance of symbiotic interactions in plant adaptation to edaphic conditions. Specifically, our findings illustrate that the importance of these relationships are not limited to alleviating macronutrient deficiencies.