Effects of Astragalus polysaccharides on P-glycoprotein efflux pump function and protein expression in H22 hepatoma cells in vitro

Anticancer Mechanism of Astragalus Polysaccharide and Its Application in Cancer Immunotherapy

Astragalus polysaccharide (APS) derived from A. membranaceus plays a crucial role in traditional Chinese medicine. These polysaccharides have shown antitumor effects and are considered safe. Thus, they have become increasingly important in cancer immunotherapy. APS can limit the spread of cancer by influencing immune cells, promoting cell death, triggering cancer cell autophagy, and impacting the tumor microenvironment. When used in combination with other therapies, APS can enhance treatment outcomes and reduce toxicity and side effects. APS combined with immune checkpoint inhibitors, relay cellular immunotherapy, and cancer vaccines have broadened the application of cancer immunotherapy and enhanced treatment effectiveness. By summarizing the research on APS in cancer immunotherapy over the past two decades, this review elaborates on the anticancer mechanism of APS and its use in cancer immunotherapy and clinical trials. Considering the multiple roles of APS, this review emphasizes the importance of using APS as an adjunct to cancer immunotherapy and compares other polysaccharides with APS. This discussion provides insights into the specific mechanism of action of APS, reveals the molecular targets of APS for developing effective clinical strategies, and highlights the wide application of APS in clinical cancer therapy in the future.

Effect of Astragali radix extract on pharmacokinetic behavior of dapagliflozin in healthy and type 2 diabetic rats

Objective: This study aimed to investigate effect of antidiabetic herb Astragali Radix (AR) on pharmacokinetic behavior of dapagliflozin (DAPA) in healthy rats and type 2 diabetes mellitus (T2DM) rats. Methods: The T2DM rats were induced by high-fat diet (HFD) and intraperitoneal injection of streptozotocin (STZ). Concentrations of DAPA in healthy and T2DM rat plasma were determined by UPLC-MS/MS method. Effect of AR extract (ARE) on pharmacokinetic behavior of DAPA in healthy and T2DM rats was evaluated, respectively. Results: The diabetes status and co-administrated with ARE significantly affected pharmacokinetic behaviors of DAPA in the rats. Compared to that in healthy rats, t max of DAPA significantly shortened, its C max significantly increased in T2DM rats, and its t 1/2, V, AUC, CL and MRT kept unchanged. When ARE was co-administrated with DAPA, C max of DAPA significantly increased, its t max and MRT significantly decreased, and its t 1/2, V, AUC and CL kept unchanged in healthy rats. t max and C max of DAPA significantly decreased, its t 1/2 and V significantly increased, and its AUC, CL and MRT were unchanged in T2DM rats when ARE was co-administrated with DAPA. Co-administration of DAPA and ARE promoted absorptive rate of DAPA, increased its extravascular tissue distribution, and prolonged its duration of action. ARE did not cause accumulation of DAPA in vivo. Conclusion: Both disease status of T2DM and co-administration of ARE affect pharmacokinetic behavior of DAPA in vivo. Potential pharmacokinetic interactions may occur in vivo when herbs and drugs are co-administrated, which may affect efficacy and safety of drugs.

Synergist for antitumor therapy: Astragalus polysaccharides acting on immune microenvironment

Various new treatments are emerging constantly in anti-tumor therapies, including chemotherapy, immunotherapy, and targeted therapy. However, the efficacy is still not satisfactory. Astragalus polysaccharide is an important bioactive component derived from the dry root of Radix astragali. Studies found that astragalus polysaccharides have gained great significance in increasing the sensitivity of anti-tumor treatment, reducing the side effects of anti-tumor treatment, reversing the drug resistance of anti-tumor drugs, etc. In this review, we focused on the role of astragalus polysaccharides in tumor immune microenvironment. We reviewed the immunomodulatory effect of astragalus polysaccharides on macrophages, dendritic cells, natural killer cells, T lymphocytes, and B lymphocytes. We found that astragalus polysaccharides can promote the activities of macrophages, dendritic cells, natural killer cells, T lymphocytes, and B lymphocytes and induce the expression of a variety of cytokines and chemokines. Furthermore, we summarized the clinical applications of astragalus polysaccharides in patients with digestive tract tumors. We summarized the effective mechanism of astragalus polysaccharides on digestive tract tumors, including apoptosis induction, proliferation inhibition, immunoactivity regulation, enhancement of the anticancer effect and chemosensitivity. Therefore, in view of the multiple functions of astragalus polysaccharides in tumor immune microenvironment and its clinical efficacy, the combination of astragalus polysaccharides with antitumor therapy such as immunotherapy may provide new sparks to the bottleneck of current treatment methods.

The effects of Astragalus polysaccharides, tragacanthin, and bassorin on methotrexate-resistant acute lymphoblastic leukemia

Background and purpose

One strategy to overcome methotrexate (MTX) resistance in acute lymphoblastic leukemia is suppressing MDR1 expression. It has been proved Astragalus polysaccharides (APS) exert their anticancer effect by reversing drug resistance. Due to the structural similarity of tragacanthin and bassorin with APS, we aimed to investigate the effects of the aforementioned polysaccharides on the expression of the MDR1 gene in the MTX-treated CCRF-CEM cells.

Experimental approach

Cytotoxicity of APS, bassorin, and tragacanthin on CCRF-CEM, CCRF-CEM/MTX (cells treated with MTX at IC50), and CCRF-CEM/R cells (CCRF-CEM cells resistant to MTX) was evaluated by MTT assay. The effect of all three compounds on MDR1 expression was evaluated using RT-PCR.

Findings/Results

All the concentrations of tragacanthin, bassorin, and APS (except at 0.8-100 μg/mL in CCRF-CEM) decreased the viability of all the cells compared to the negative control group; and against the positive control (MTX-treated cells), only bassorin at 20-100 μg/mL in CCRF-CEM/R and tragacanthin at 50 and 100 μg/mL in CCRF-CEM/MTX and at 2-100 μg/mL in CCRF-CEM/R decreased cell viability. Tragacanthin diminished MDR1 expression in CCRF-CEM/MTX and CCRF-CEM/R cells, which MTX had already induced.

Conclusion and implication

According to the results of this study, tragacanthin was a potent cytotoxic agent against CCRF-CEM cells and enhanced the chemosensitivity of CCRF-CEM/MTX and CCRF-CEM/R cells to MTX by down-regulation of MDR1 gene expression. Therefore, it could be a promising compound against cancer. Other possible mechanisms of action of tragacanthin should be evaluated and further in vitro and in vivo investigations are required.

Effect of decoction of Fuzheng Jiedu Xiaoji formula plus chemoembolization on primary liver cancer in patients

OBJECTIVE

To investigate the effect of the decoction of Fuzheng Jiedu Xiaoji formula (, FJXF) plus chemoembolization (TACE) on primary liver cancer (PLC) in patients, and study the underlying mechanism.

METHODS

Patients with PLC who met the inclusion criteria were randomized into case group and control group. The case group was treated with FJXF combined with TACE. The control group was treated with TACE alone. The short-term clinical effect was evaluated; liver biochemistry, liver function index and multidrug resistance-associated indicators were detected.

RESULTS

FJXF combined with TACE in the case group significantly increased the disease control rate than TACE alone in the control group (83.3% 61.1%). There was a reduction in the serum alpha-fetoprotein at 8 weeks after treatment in each group, while no difference between the two groups. The same trend can be observed for transaminase and direct bilirubin in both groups. In the case group, it showed a significant increase for albumin at 8 weeks after treatment, while no change in the control group. Multidrug resistance-associated indicators for multidrug resistance protein 1 and p-glycoprotein were upregulated in the case group but remained stable in the control group.

CONCLUSIONS

FJXF combined TACE had a better short-term effect than TACE alone in patients with PLC. The potential mechanism was probably associated with alleviated multidrug resistance induced by FJXF. Additionally, FJXF didn't increase the risk of liver damage in the combined therapy.

Astragalus Polysaccharides Inhibits Tumorigenesis and Lipid Metabolism Through miR-138-5p/SIRT1/SREBP1 Pathway in Prostate Cancer

Astragalus polysaccharides (APS) is a traditional Chinese medicine and have been proved to involve in multiple biological processes, including inflammation, metabolism, and carcinogenics. However, the specific mechanisms by which APS on prostate cancer (PCa) remains largely unknown. In the current study, we found APS greatly inhibited the proliferation and invasion of PCa cells in a dose-dependent and time-dependent manner in vitro and in vivo. In addition, cellular triglyceride and cholesterol levels were also decreased significantly under APS treatment. Microarray data revealed the SIRT1 expression was markably suppressed under APS exposure. Mechanistic studies demonstrated that over-expression of SIRT1 inhibits the expression and nuclear translocation of SREBP1 via activating AMPK phosphorylation to suppress lipid metabolism. Otherwise, knockdown of SIRT1 significantly promotes AMPK/SREBP1 signaling and its associated target genes. Besides, we also found miR-138-5p was greatly inhibited the SIRT1 expression to regulating cell metabolism by targeting its 3′UTR region. To summarize, our findings suggested that APS inhibits tumorigenesis and lipid metabolism through miR-138-5p/SIRT1/SREBP1 pathways in PCa.

Interaction between phytotherapy and oral anticancer agents: prospective study and literature review

Cancer is becoming more prevalent in elderly patient. Due to polypharmacy, older adults with cancer are predisposed to drug-drug interactions. There is also an increasing interest in the use of complementary and alternative medicine (CAM). Thirty to seventy percent of patients with cancer have used CAM. Through pharmaceutical counseling sessions, we can provide advices on herb-drug interactions (HDI). All the patients seen in pharmaceutical counseling sessions were prospectively included. Information was collected during these sessions: prescribed medication (oral anticancer agents (OAA) and other drugs), CAM (phytotherapy especially), and use of over-the-counter (OTC) drugs. If pharmacist considered an interaction or an intervention clinically relevant, the oncologist was notified. Then, a literature review was realized to identify the potential HDI (no interactions, precautions for use, contraindication). Among 201 pharmacist counseling sessions, it resulted in 104 interventions related to 46 HDI, 28 drug-drug interactions and 30 others (wrong dosage, omission…). To determine HDI, we review 73 medicinal plants which are used by our patients with cancer and 31 OAA. A total of 1829 recommendations were formulated about 59 (75%) medical plants and their interaction with an OAA. Herb-drug interactions should not be ignored by healthcare providers in their management of cancer patients in daily practice.

Recent Advances in Herbal Medicines for Digestive System Malignancies

Herbal medicines, as an important part of traditional Chinese medicine (TCM), have been used to treat digestive system malignancies (DSM) for many years, and have gradually gained recognition worldwide. The role of herbal medicines in the comprehensive treatment of DSM is being improved from adjuvant treatment of the autologous immune function in cancer patients, to the treatment of both the symptoms and disease, direct inhibition of tumor cell growth and proliferation, and induction of tumor cell autophagy and apoptosis. Their specific mechanisms in these treatments are also being explored. The paper reviews the current anti-tumor mechanisms of TCM, including single herbal medicines, Chinese herbal formulations, Chinese medicine preparations and TCM extract, and their application in the comprehensive treatment of digestive system tumors, providing a reference for clinical application of TCM.

Traditional Chinese medicine Astragalus polysaccharide enhanced antitumor effects of the angiogenesis inhibitor apatinib in pancreatic cancer cells on proliferation, invasiveness, and apoptosis

Background

Traditional chemotherapy and molecular targeted therapy have shown modest effects on the survival of patients with pancreatic cancer. The current study aimed to investigate the antitumor effects of apatinib, Astragalus polysaccharide (APS), and the combination of both the drugs in pancreatic cancer cells and further explore the molecular mechanisms in vitro.

Materials and methods

Expression of vascular endothelial growth factor receptor-2 (VEGFR-2) in human pancreatic cancer cell lines ASPC-1, PANC-1, and SW1990 was detected by Western blotting. Cell proliferation was measured by MTS, and migration and invasion were detected by wound-healing and Transwell assays, respectively. Cell apoptosis rate was determined by flow cytometry and cellular autophagy level affected by apatinib, and APS was analyzed by Western blotting.

Results

Human pancreatic cancer cell lines ASPC-1 and PANC-1 expressed VEGFR-2, but VEGFR-2 was not detected in SW1990. Either apatinib or APS inhibited cell proliferation in a dose-dependent manner in ASPC-1 and PANC-1. APS in combination with apatinib showed enhanced inhibitory effects on cell migration and invasion compared with apatinib monotherapy in ASPC-1 and PANC-1. Meanwhile, APS combined with apatinib strongly increased cell apoptosis percentage. Western blotting showed that the combination of APS and apatinib significantly enhanced the downregulation of phosphorylated protein kinase B (AKT) and extracellular signal-regulated kinase (ERK) (p-AKT and p-ERK) as well as matrix metalloproteinases-9 (MMP-9) expression. In addition, both apatinib and APS induced cellular autophagy. However, the expression of autophagy-related proteins was not further elevated in the combination group.

Conclusion

The study first demonstrated that apatinib showed potentially inhibitory effects in pancreatic cancer cells and that APS enhanced the antitumor effects of apatinib through further downregulating the expression of phosphorylation of AKT and ERK as well as MMP-9.

Soybean soluble polysaccharide enhances absorption of soybean genistein in mice

This study was designed to probe the promoting effects of soybean soluble polysaccharide (SSPS) on bioavailability of genistein in mice and the underlying molecular mechanism. Male Kunming mice (n=8) were administered intragastrically with either saline, SSPS (5mg/kgbw), genistein (100mg/kgbw), or SSPS (5 or 50mg/kgbw) together with genistein (100mg/kgbw) for consecutive 28days. UPLC-qTOF/MS analysis showed that co-administration of SSPS and genistein in mice caused significant elevation in the urinary levels of genistein and its metabolites (p<0.05). Furthermore, the fecal excretion of genistein was also enhanced by co-administration of SSPS. However, the feces level of dihydrogenistein, a characteristic metabolite of genistein degraded by gut microorganism, was dose-dependently decreased by the combined treatment of SSPS. Additionally, co-treatment of SSPS with genistein also decreased the small intestinal levels of uridinediphosphate-glucuronosyltransferase (UGT), sulfotransferase (SULT), P-glycoprotein (P-gp), multidrug resistance-associated protein-1 (MRP1), and multidrug resistance-associated protein-2 (MRP2) in mice. These findings suggest that the inhibition of SSPS against small intestinal first-pass metabolism of genistein is involved in the promoting effect of genistein bioavailability in mice.

Astragalus polysaccharides inhibit avian infectious bronchitis virus infection by regulating viral replication

The avian coronavirus causes infectious bronchitis (IB), which is one of the most serious diseases affecting the avian industry worldwide. However, there are no effective strategies for controlling the IB virus (IBV) at present. Therefore, development of novel antiviral treatment strategies is urgently required. As reported, astragalus polysaccharides (APS) have potential antiviral effects against several viruses; however, the antiviral effect of APS against IBV remains unclear. In this study, we explored whether APS had the potential to inhibit IBV infectionby utilizing several in vitro experimental approaches. To this end, the effect of APS on the replication of IBV was examined in chicken embryo kidney (CEK) cells. Viral titers were calculated by using the plaque formation assay, and the cytotoxicity of APS was tested by utilizing a Cell Counting Kit-8 assay. The expression of viral mRNA and cytokine (IL-1β, IL-6, IL-8 and TNF-α) mRNA transcripts was determined by real-time quantitative RT-PCR(qRT-PCR). IBV titers in infected CEK cells treated with APS were significantly reduced in a dose-dependent manner, indicating that APS inhibited IBV replication in vitro. We also found that the decreased viral replication after APS treatment was associated with reduced mRNA levels of the cytokines IL-1B, IL-6, IL-8 and TNF-α. In conclusion, these results suggest that APS exhibit antiviral activities against IBV and it may represent a potential therapeutic agent for inhibiting the replication of IBV.

Astragalus polysaccharides exerts immunomodulatory effects via TLR4-mediated MyD88-dependent signaling pathway in vitro and in vivo

Astragalus polysaccharides (APS), which is widely used as a remedy to promote immunity of breast cancer patients, can enhance immune responses and exert anti-tumor effects. In this study, we investigated the effects and mechanisms of APS on macrophage RAW 264.7 and EAC tumor-bearing mice. Griess reaction and ELISA assays revealed that the concentrations of nitric oxide, TNF-α, IL-1β and IL-6 were increased by APS. However, this effect was diminished in the presence of TAK-242 (TLR4 inhibitor) or ST-2825(MyD88 inhibitor). In C57BL/10J (TLR4^+/+wild-type) and C57BL/6J (MyD88^+/+wild-type) tumor-bearing mice, the tumor apoptosis rate, immune organ indexes and the levels of TNF-α, IL-1β and IL-6 in blood increased and the tumor weight decreased by oral administration of APS for 25 days. APS had no obvious effects on IL-12p70. However, these effects were not significant in C57BL/10ScNJ (TLR4-deficient) and C57BL/B6.129P2(SJL)-Myd88^m1.1Defr/J (MyD88-deficient) tumor-bearing mice. qRT-PCR and Western blot indicated that APS stimulated the key nodes in the TLR4-MyD88 dependent signaling pathway, including TLR4, MyD88, TRAF-6, NF-κB and AP-1, both in vitro and in vivo. However, TRAM was an exception. Moreover, TRAF-6 and NF-κB were not triggered by APS in gene-deficient tumor-bearing mice. Therefore, APS may modulate immunity of host organism through activation of TLR4-mediated MyD88-dependent signaling pathway.

Advances on Bioactive Polysaccharides from Medicinal Plants

In recent decades, the polysaccharides from the medicinal plants have attracted a lot of attention due to their significant bioactivities, such as anti-tumor activity, antioxidant activity, anticoagulant activity, antidiabetic activity, radioprotection effect, anti-viral activity, hypolipidemic and immunomodulatory activities, which make them suitable for medicinal applications. Previous studies have also shown that medicinal plant polysaccharides are non-toxic and show no side effects. Based on these encouraging observations, most researches have been focusing on the isolation and identification of polysaccharides, as well as their bioactivities. A large number of bioactive polysaccharides with different structural features and biological effects from medicinal plants have been purified and characterized. This review provides a comprehensive summary of the most recent developments in physiochemical, structural features and biological activities of bioactive polysaccharides from a number of important medicinal plants, such as polysaccharides from Astragalus membranaceus, Dendrobium plants, Bupleurum, Cactus fruits, Acanthopanax senticosus, Angelica sinensis (Oliv.) Diels, Aloe barbadensis Miller, and Dimocarpus longan Lour. Moreover, the paper has also been focused on the applications of bioactive polysaccharides for medicinal applications. Recent studies have provided evidence that polysaccharides from medicinal plants can play a vital role in bioactivities. The contents and data will serve as a useful reference material for further investigation, production, and application of these polysaccharides in functional foods and therapeutic agents.

Chemosensitizing Effect of Astragalus Polysaccharides on Nasopharyngeal Carcinoma Cells by Inducing Apoptosis and Modulating Expression of Bax/Bcl-2 Ratio and Caspases

Background

Platinum-based chemotherapy is the most effective regimen for nasopharyngeal carcinoma, which presents highly invasive and metastatic activity. However, the dose-related toxicity of chemotherapy agents limits the dose administration. Astragalus polysaccharide (APS) is the major active ingredient extracted from Chinese herb Radix Astragali and is proven to be active against carcinomas. We aimed to assess the chemosensitizing effects of Astragalus polysaccharides on nasopharyngeal carcinoma in vitro and in vivo and to explore the underlying mechanism.

Material/Methods

We used BALB/c nu/nu mice and human nasopharyngeal carcinoma cell lines CNE-1, CNE-2, and SUNE-1. MTT, Annexin V/PI, Western blot analysis, and TUNEL assay were carried out.

Results

APS significantly promoted anti-proliferative and apoptotic effects of cisplatin on nasopharyngeal carcinoma cells. APS also enhanced the anti-tumor effects and cisplatin-induced apoptosis in the xenograft model. The level of Bcl-2 decreased, while the levels of Bax, caspase-3, and caspase-9 increased in cisplatin combined with APS treatment compared to cisplatin only treatment. The ratio of Bax to Bcl-2 was significantly enhanced by the APS to cisplatin.

Conclusions

APS enhanced the anti-proliferative and apoptotic effect of cisplatin by modulating expression of Bax/Bcl-2 ratio and caspases on nasopharyngeal carcinoma cells and in the xenograft model.

Regulation of drug-metabolizing enzymes and efflux transporters by Astragali radix decoction and its main bioactive compounds: Implication for clinical drug-drug interactions

ETHNOPHARMACOLOGICAL RELEVANCE

Astragali radix ("Huang Qi" in Chinese, HQ) is a well-known traditional Chinese herbal medicine that possesses various biological functions. Astragaloside IV (AS-IV), calycosin (CS), and formononetin (FMNT) are the three main bioactive compounds of HQ that are responsible for its pharmacological activities and therapeutic efficacy.

AIM OF THE STUDY

This study aims to investigate the effects of HQ, AS-IV, CS, and FMNT on major human drug-metabolizing enzymes (DMEs), including CYP3A4, CYP2B6, CYP2E1, UGT1A, UGT1A6, SULT1A1, and SULT1A3, as well as efflux transporters (ETs), including P-gp, MRP2, BCRP, MRP1, and MRP3, by using HepG2 cell line. Results would provide beneficial information for the proper clinical application of HQ.

MATERIALS AND METHODS

HepG2 cells were treated with HQ, AS-IV, CS, and FMNT for 96h. Cell viability was examined by MTT assay. The protein and mRNA levels of DMEs and ETs were measured using Western blot and real-time PCR, respectively.

RESULTS

Compared with the control group, HQ considerably increased the expression levels of CYP3A4, CYP2B6, CYP2E1, UGT1A, P-gp, MRP2, BCRP, and MRP3 in a dose-dependent manner. Inversely, HQ significantly decreased the protein levels of UGT1A6, SULT1A1, and MRP1. Exposure to AS-IV induced the protein levels of UGT1A, P-gp, MRP1, and MRP3, but produced inhibitory effects on CYP3A4, CYP2B6, and BCRP. The expression levels of CYP3A4, UGT1A, SULT1A1, P-gp, MRP2, and MRP3 were remarkably increased in the CS-treated cells, whereas the protein levels of SULT1A3 and BCRP were decreased. FMNT treatment induced the protein levels towards CYP3A4, CYP2B6, UGT1A, P-gp, MRP1, MRP2, and MRP3, but inhibited the expression of CYP2E1, SULT1A1, and SULT1A3.

CONCLUSIONS

HQ and its main bioactive compounds, including AS-IV, CS, and FMNT significantly regulated the expression of the major DMEs and ETs. HQ produced stronger regulations (induction or inhibition) on DMEs and ETs than AS-IV, CS, or FMNT alone. The results indicate that potential drug-drug interactions might exist when the tested drugs, specifically HQ, are co-administered with other substrate drugs that are metabolized or transported via the studied DMEs or ETs. This study provides beneficial information for appropriate use of HQ for clinical therapy.

The Anti-Oxidant and Antitumor Properties of Plant Polysaccharides

Oxidative stress has been increasingly recognized as a major contributing factor in a variety of human diseases, from inflammation to cancer. Although certain parts of signaling pathways are still under investigation, detailed molecular mechanisms for the induction of diseases have been elucidated, especially the link between excessive oxygen reactive species (ROS) damage and tumorigenesis. Emerging evidence suggests anti-oxidant therapy can play a key role in treating those diseases. Among potential drug resources, plant polysaccharides are natural anti-oxidant constituents important for human health because of their long history in ethnopharmacology, wide availability and few side effects upon consumption. Plant polysaccharides have been shown to possess anti-oxidant, anti-inflammation, cell viability promotion, immune-regulation and antitumor functions in a number of disease models, both in laboratory studies and in the clinic. In this paper, we reviewed the research progress of signaling pathways involved in the initiation and progression of oxidative stress- and cancer-related diseases in humans. The natural sources, structural properties and biological actions of several common plant polysaccharides, including Lycium barbarum, Ginseng, Zizyphus Jujuba, Astragalus lentiginosus, and Ginkgo biloba are discussed in detail, with emphasis on their signaling pathways. All of the mentioned common plant polysaccharides have great potential to treat oxidative stress and cancinogenic disorders in cell models, animal disease models and clinical cases. ROS-centered pathways (e.g. mitochondrial autophagy, MAPK and JNK) and transcription factor-related pathways (e.g. NF-[Formula: see text]B and HIF) are frequently utilized by these polysaccharides with or without the further involvement of inflammatory and death receptor pathways. Some of the polysaccharides may also influence tumorigenic pathways, such as Wnt and p53 to play their anti-tumor roles. In addition, current problems and future directions for the application of those plant polysaccharides are also listed and discussed.

A systematic review of anticancer effects of radix astragali

OBJECTIVE

To review the anticancer effects of Radix astragali (RA), one of the most commonly used herbs to manage cancer in East Asia, and its constituents and to provide evidence of clinical usage through previously performed clinical studies.

METHODS

Preclinical and clinical studies related to the anticancer effects of RA were searched from inception to November 2013 in electronic databases. Two reviewers independently investigated 92 eligible studies, extracted all the data of studies and appraised methodological quality of clinical trials. The studies were categorized into in vitro and in vivo experimental studies and clinical studies, and analyzed by saponins, polysaccharides, and flavonoids of RA constituents, RA fraction, and whole extract.

RESULTS

In preclinical studies, RA was reported to have tumor growth inhibitory effects, immunomodulatory effects, and attenuating adverse effects by cytotoxic agents as well as chemopreventive effects. Saponins seemed to be the main constituents, which directly contributed to suppression of tumor growth through the activation of both intrinsic and extrinsic apoptotic pathway, modulation of intracellular signaling pathway, and inhibition of invasion and angiogenesis. Flavonoids suppressed tumor growth through the similar mechanisms with saponins. Polysaccharides showed immunomodulatory effects, contributing tumor shrinkages in animal models, despite the low cytotoxicity to cancer cells. Most of the clinical studies were performed with low evidence level of study designs because of various limitations. RA whole extracts and polysaccharides of RA were reported to improve the quality of life and ameliorate myelosuppression and other adverse events induced by cytotoxic therapies.

CONCLUSION

The polysaccharides, saponins, and flavonoids of RA, and the whole extract of RA have been widely reported with their anticancer effects in preclinical studies and showed a potential application as a adjunctive cancer therapeutics with the activities of immunomodulation, anti-proliferation and attenuation of adverse effects induced by cytotoxic therapy.

An in vivo molecular response analysis of colorectal cancer treated with Astragalus membranaceus extract

The fact that many chemotherapeutic drugs cause chemoresistance and side effects during the course of colorectal cancer treatment necessitates development of novel cytotoxic agents aiming to attenuate new molecular targets. Here, we show that Astragalus membranaceus (Fischer) Bge. var. mongolicus (Bge.) Hsiao (AM), a traditional Chinese medicine, can inhibit tumor growth in vivo and elucidate the underlying molecular mechanisms. The antitumor effect of AM was assessed on the subcutaneous tumors of human colorectal cancer cell line HCT116 grafted into nude mice. The mice were treated with either water or 500 mg/kg AM once per day, before being sacrificed for extraction of tumors, which were then subjected to microarray expression profiling. The gene expression of the extraction was then profiled using microarray analysis. The identified genes differentially expressed between treated mice and controls reveal that administration of AM suppresses chromosome organization, histone modification, and regulation of macromolecule metabolic process. A separate analysis focused on differentially expressed microRNAs revealing involvement of macromolecule metabolism, and intracellular transport, as well as several cancer signaling pathways. For validation, the input of the identified genes to The Library of Integrated Network-based Cellular Signatures led to many chemopreventive agents of natural origin that produce similar gene expression profiles to that of AM. The demonstrated effectiveness of AM suggests a potential therapeutic drug for colorectal cancer.

Notch1/3 and p53/p21 are a potential therapeutic target for APS-induced apoptosis in non-small cell lung carcinoma cell lines

OBJECTIVE

Previous studies have shown that Astragalus polysaccharide (APS) can be applied to anti-cancer. However, the mechanism by which APS mediate this effect is unclear. In the present study, APS-mediated NSCLC cell apoptosis was investigated through the regulation of the notch signaling pathway.

METHODS

The cell viability was detected by the CCK8 assay. The mRNA and protein expression of notch1/3 and tumor suppressors were analyzed by RT-PCR and western blotting, respectively.

RESULTS

The mRNA and protein of notch1 and notch3 were significantly up-regulated in tumor tissues as compared to non-tumor adjacent tissues. Treatment of human NSCLC cells with APS induced cell death in a dose-and time-dependent manner by using CCK8 assay. The mRNA and protein expression of notch1 and notch3 were significantly lower in NSCLC cells with APS treatment than that in control group. Moreover, western blotting analysis showed that treatment of H460 cells with APS significantly increased the pro-apoptotic Bax and caspase 8 levels, decreased the anti-apoptotic Bcl-2 level. Furthermore, p53, p21 and p16 were obviously up-regulated by APS treatment in H460 cell.

CONCLUSIONS

This study demonstrated that APS-treated could inhibit proliferation and promote cell apoptosis, at least partially, through suppressing the expression of notch1 and notch3 and up-regulating the expression of tumor suppressors in H460 NSCLC cell lines.

Gene Expression Profiling and Pathway Network Analysis Predicts a Novel Antitumor Function for a Botanical-Derived Drug, PG2

PG2 is a botanical drug that is mostly composed of Astragalus polysaccharides (APS). Its role in hematopoiesis and relieving cancer-related fatigue has recently been clinically investigated in cancer patients. However, systematic analyses of its functions are still limited. The aim of this study was to use microarray-based expression profiling to evaluate the quality and consistency of PG2 from three different product batches and to study biological mechanisms of PG2. An integrative molecular analysis approach has been designed to examine significant PG2-induced signatures in HL-60 leukemia cells. A quantitative analysis of gene expression signatures was conducted for PG2 by hierarchical clustering of correlation coefficients. The results showed that PG2 product batches were consistent and of high quality. These batches were also functionally equivalent to each other with regard to how they modulated the immune and hematopoietic systems. Within the PG2 signature, there were five genes associated with doxorubicin: IL-8, MDM4, BCL2, PRODH2, and BIRC5. Moreover, the combination of PG2 and doxorubicin had a synergistic effect on induced cell death in HL-60 cells. Together with the bioinformatics-based approach, gene expression profiling provided a quantitative measurement for the quality and consistency of herbal medicines and revealed new roles (e.g., immune modulation) for PG2 in cancer treatment.

Astragalus polysaccharide suppresses palmitate-induced apoptosis in human cardiac myocytes: the role of Nrf1 and antioxidant response

OBJECTIVE

Previous studies have shown that Astragalus polysaccharides (APS) can be used to ameliorate cardiotoxicity due to chemotherapy and improve the cardiac function. However, the mechanism by which APS mediate this effect is unclear. In the present study, the effects of APS, which suppressed ROS-mediated apoptosis through Nrf1 accumulation in human cardiac myocytes (HCMs), was investigated.

METHODS

The cell viability was detected by the CCK8 assay. The cell apoptosis was assessed by annexin V-PI double-labeling staining. Expression of genes and proteins were analyzed by real-time PCR and western blotting respectively. Nrf1 gene was overexpressed using a lentiviral expression vector in HCMs in vitro, in order to explore the mechanism by which the Nrf1 promoted cell growth.

RESULTS

CCK8 and Annexin V-PI double-labeling showed that PAL induced cell death in a concentration-dependent manner, and suppressed HCMs proliferation. The combination PAL with APS was significantly decreased the percentage of the early phase of apoptosis cells. ROS levels were increased in HCMs by exposure to PAL. APS treatment significantly inhibited generation of ROS in response to palmitate. Moreover, PAL administration significantly decreased the mRNA and proteins expression of Bcl-2 as well as increased the mRNA expression of BAX and the protein expression of caspase-3 and caspase-8 as compare to those of control group, but APS treatment could reverse PA-induced HCMs apoptosis. The levels of reactive oxygen species (ROS), which was an oxidative stress marker, was significantly increased in cardiomyocytes by exposure to PAL, but overexpressing Nrf1 could ameliorate ROS-induced cardiomyocyte toxicity and increase the expression of SOD1 and SOD2 in HCMs by overexpressing Nrf1.

CONCLUSIONS

This study demonstrated that the PAL could induce HCMs apoptosis. However, APS could reverse PAL-induced cardiomyocyte toxicity, at least partially, through suppression ROS and Nrf1 accumulation in HCMs.

Fuzheng Qingjie recipe induces apoptosis in HepG2 cells via P38 MAPK activation and the mitochondria-dependent apoptotic pathway

Fuzheng Qingjie (FZQJ) recipe is a polyherbal Chinese medicine capable of suppressing tumor growth and is used as an adjuvant therapy for various types of cancer. However, its anticancer mechanisms are yet to be fully elucidated. In the present study, we explored whether p38 mitogen-activated protein kinase (MAPK) was involved in FZQJ-mediated mitochondria-dependent apoptosis in human hepatocellular carcinoma cells. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays were used to measure the viability of HepG2 cells. 4,6-Diamidino-2-phenylindole (DAPI) and Annexin-V fluorescein isothiocyanate (FITC) were used to analyze the apoptosis of HepG2 cells. The mitochondrial membrane potential (∆ψ) and phosphorylated P38 MAPK protein were examined by a flow cytometer following 5,5',6,6'-tetrachloro‑1,1',3,3'-tetraethylbenzimidazolcarbocyanine iodide (JC-1) and Alexa Fluor® 647 mouse anti-phosphorylated P38 MAPK antibody staining, respectively. The activation of caspase-9 and caspase-3 were measured using colorimetric assays. Additionally, Bcl-2 and Bax expression were examined using reverse transcription polymerase chain reaction (RT-PCR) and western blot analysis. The results demonstrated that water extract of FZQJ was able to induce apoptosis of HepG2 cells in vitro. FZQJ-induced apoptosis was accompanied by the loss of ∆ψ, downregulation of Bcl-2 and upregulation of Bax expression, and the activation of caspase-3, -9 and P38 MAPK. These results indicated that FZQJ induced apoptosis in HepG2 cells at least via P38 MAPK activation and the mitochondria-dependent apoptotic pathway.

Towards novel anti-tumor strategies for hepatic cancer: ɛ-viniferin in combination with vincristine displays pharmacodynamic synergy at lower doses in HepG2 cells

Hepatocellular carcinoma is the fifth most common cancer and the third leading cause of cancer-related deaths worldwide. The efficacy of novel combination treatments are increasingly evaluated with use of integrative biology research and development (R&D) strategies and methodological triangulation. We investigated the anti-tumor effect of ɛ-viniferin alone, and the putative synergy of ɛ-viniferin with vincristine on the growth of HepG2 cells in vitro. Growth inhibition and apoptosis induction were determined by MTT assay and annexin V/propidium iodide (PI), respectively. Morphological changes and DNA fragmentation were investigated under electron microscopy and by agarose gel electrophoresis, respectively. The results collectively showed that treating cells with ɛ-viniferin and vincristine significantly inhibited cell viability at lower doses as compared to each agent applied alone. IC(50) values for ɛ-viniferin and vincristine were determined as 98.3 and 52.5 μM at 24 h, respectively. IC(50) value of ɛ-viniferin in combination with vincristine was 15.8+11.25 μM (mean/SD) at 24 h. The viability of cells treated with 17.9 μM vincristine alone for 24 h was 79.62%; it reduced to 26.53% when 25 μM ɛ-viniferin was added in combination with vincristine (p<0.05). We found that combination of drugs promoted the sensitivity of cells against to vincristine treatment. The effect of combined use was in support of a synergistic pharmacodynamic effect. Moreover, low doses of the combination regimen induced phosphatidyl re-localization, morphological changes, and DNA fragmentation, and therefore caused apoptotic death. This study thus suggests that low concentrations of ɛ-viniferin and vincristine can enhance the anti-tumor effects efficiently by inducing HepG2 cell apoptosis. Further studies in other model systems are warranted with a view to potential future applications in the clinic of such combination regimens and their putative mechanism of action in the observed synergy reported here.

Structural features and biological activities of the polysaccharides from Astragalus membranaceus

Recently, a great deal of interest has been developed to isolate and investigate novel bioactive components with health benefit effects from natural resources. The dried root of Astragalus membranaceus, one of the most popular health-promoting herbal medicines, has been used historically as an immunomodulating agent for the treatment of common cold, diarrhea, fatigue and anorexia for more than 2000 years. Modern phytochemistry and pharmacological experiments have proved that polysaccharide is one of the major active ingredients in the root of A. membranaceus with various important bioactivities, such as immunomodulation, antioxidant, antitumor, anti-diabetes, antiviral, hepatoprotection, anti-inflammation, anti-atherosclerosis, hematopoiesis and neuroprotection. The aim of the present review is to summarize previous and current references and give a comprehensive summary regarding the structural features and biological activities of A. membranaceus polysaccharides in order to provide new insight for further development of these macromolecules.

Investigation on modulation of human P-gp by multiple doses of Radix Astragali extract granules using fexofenadine as a phenotyping probe

ETHNOPHARMACOLOGY

Herb-drug interactions may potentially affect drug efficacy and/or the likelihood of adverse drug reactions. Radix Astragali (RA) extract formulation is usually prescribed for long-term use for patients with immunodeficiency, diabetes, nephropathy or cardiovascular diseases. Its use in combination with P-glycoprotein (P-gp) substrates is possible in clinical practice. Currently there is little knowledge about whether concomitant use of RA extract has an influence on disposition of P-gp substrate.

AIM OF THE STUDY

This study was to investigate whether continuous and multiple doses of RA extract granules had modulatory effects on human P-gp.

MATERIAL AND METHODS

A randomised, placebo-controlled, two-period crossover pharmacokinetic drug interaction study was conducted in healthy Chinese volunteers. Fexofenadine was used as a P-gp phenotyping probe. Fourteen volunteers received RA extract granules or placebo (4g bid) for 7 days and then received a single oral dose of 120mg fexofenadine. Fexofenadine plasma concentrations were determined by HPLC. Pharmacokinetic parameters were calculated by non-compartmental method and bioequivalence evaluation was performed.

RESULTS

Pharamcokinetic parameters in the placebo phase were as follows: T1/2 (3.75±1.47h), Cmax (745.11±137.41μg/L), Tmax (2.25±0.47h), AUC(0-t) (3894.27±923.45μgh/L), AUC(0-∞) (3993.84±912.97μgh/L). Pharamcokinetic parameters in the RA extract phase were as follows: T1/2 (4.00±1.24h), Cmax (709.44±170.03μg/L), Tmax (2.21±0.51h), AUC(0-t) (3832.72±1077.60μgh/L), AUC(0-∞) (3983.53±1019.83μgh/L). The influence of RA extract on fexofenadine Cmax and AUC lacks statistical significance. Fexofenadine in the two phases were bioequivalent. In the placebo phase, T1/2 of fexofenadine in ABCB1 3435T mutation allele carriers was longer compared to ABCB1 3435CC carriers (4.43±1.44h vs. 2.54±0.21h, p<0.05). However, RA extract pretreatment abolished such genotype-related difference due to the lengthened T1/2 in ABCB1 3435CC carriers. There was no association of the C3435T polymorphism with Cmax and AUC(0-t) in subjects with two pretreatments.

CONCLUSION

One-week administration of RA extract granules did not have a statistically significant impact on systematic exposure to fexofenadine, suggesting that RA extract is not a potent modulator of P-gp in vivo. RA extract appears to have ABCB1 C3435T genotype-dependent inhibitory effect on elimination rather than absorption of a P-gp substrate. Further investigations are necessary in patients who receive long-term use of RA extract formulation and combined P-gp substrates, especially in those ABCB1 3435CC carriers.