Astragalus polysaccharide ameliorates ionizing radiation-induced oxidative stress in mice

Biyang floral mushroom-derived exosome-like nanovesicles: characterization, absorption stability and ionizing radiation protection

Diet-derived exosome-like nanovesicles are a class of natural active substances that have similar structures and functions to mammalian exosomes. Biyang floral mushrooms and their active extracts have been found to possess radioprotective effects and to deeply explore their novel active substances, the radioprotective effects of Biyang floral mushroom-derived exosome-like nanovesicles (BFMELNs) were investigated in this study. Results showed that these surface-negatively charged vesicles possessed an ideal size and good stability against environmental changes such as temperature and gastrointestinal digestion. Furthermore, BFMELNs could effectively be taken up by HL-7702 cells and Caco-2 cells through cellular phagocytosis mediated by clathrin and dynein. Emphatically, BFMELNs with an exosome-like morphology contained RNA, proteins, lipids, polyphenols and flavonoids to exert good antioxidant and radioprotective effects in vitro. Meanwhile, BFMELNs also exhibited good radioprotective effects by restoring peripheral blood indexes, mitigating damage to organs, and regulating the redox state in mice. Collectively, BFMELNs showed promise as novel and natural radioprotective nano-agents for preventing IR-induced oxidative stress damage.

Inhibition of mtDNA-PRRs pathway-mediated sterile inflammation by astragalus polysaccharide protects against transport stress-induced cardiac injury in chicks

Transport stress (TS) not only weakens poultry performance but also affects animal welfare. Additionally, TS can evoke cardiac damage by triggering sterile inflammation in chicks, but the underlying mechanism is not fully understood. Here, we aimed to elucidate how TS induces sterile inflammation and heart injury and to clarify the antagonism effect of astragalus polysaccharides (APS). We randomly divided 60 chicks (one-day-old female) into 5 groups (n = 12): Control_0h (Con_0h) group (chicks were slaughtered at initiation), Control group (stress-free control), TS group (simulated TS exposure for 8 h), TS plus water (TS+W) group, and TS plus APS (TS+APS) group. Before simulation transport, the chicks of TS+W and TS+APS groups were, respectively, dietary with 100 μL of water or APS (250 μg/mL). H&E staining was employed for cardiac histopathological observation. ELISA assay was used to measure oxidative stress marker levels (GSH, GPX, GST, and MDA). A commercial kit was used to isolate the mitochondrial portion, and qRT-PCR was employed to measure the mitochondrial DNA (mtDNA) levels. Furthermore, we evaluated the activity of mtDNA-mediated NF-κB, NLRP3 inflammasome, and cGAS-STING inflammatory pathways and the expression of downstream inflammatory factors by Western Blotting or qRT-PCR. Our findings revealed that APS notably relieved TS-induced myocardial histopathological lesions and infiltrations. Likewise, the decrease in proinflammatory factors (TNF-α, IL-1β, and IL-6) and IFN-β by APS further supported this result. Meanwhile, TS caused severe oxidative stress in the chick heart, as evidenced by decreased antioxidant enzymes and increased MDA. Importantly, APS prevented mtDNA stress and leakage by reducing oxidative stress. Interestingly, TS-induced mtDNA leakage caused a series of inflammation events via mtDNA-PRRs pathways, including TLR21-NF-κB, NLRP3 inflammasome, and cGAS-STING signaling. Encouragingly, all these adverse changes related to inflammation events induced by mtDNA-PRRs activation were all relieved by APS treatment. In summary, our findings provide the first evidence that inhibition of mtDNA-PRRs pathway-mediated sterile inflammation by APS could protect against TS-induced cardiac damage in chicks.

The Antioxidant Action of Astragali radix: Its Active Components and Molecular Basis

Astragali radix is a traditional medicinal herb with a long history and wide application. It is frequently used in prescriptions with other medicinal materials to replenish Qi. According to the classics of traditional Chinese medicine, Astragali radix is attributed with properties such as Qi replenishing and surface solidifying, sore healing and muscle generating, and inducing diuresis to reduce edema. Modern pharmacological studies have demonstrated that some extracts and active ingredients in Astragali radix function as antioxidants. The polysaccharides, saponins, and flavonoids in Astragali radix offer beneficial effects in preventing and controlling diseases caused by oxidative stress. However, there is still a lack of comprehensive research on the effective components and molecular mechanisms through which Astragali radix exerts antioxidant activity. In this paper, we review the active components with antioxidant effects in Astragali radix; summarize the content, bioavailability, and antioxidant mechanisms; and offer a reference for the clinical application of Astragalus and the future development of novel antioxidants.

Advances in research on the anti-tumor mechanism of Astragalus polysaccharides

The dry root of the soybean plant Astragalus membranaceus (Fisch) Bge. var. mongholicus (Bge) Hsiao or A. membranaceus (Fisch) Bge, Astragali Radix (AR) has a long medicinal history. Astragalus polysaccharide (APS), the natural macromolecule that exhibits immune regulatory, anti-inflammatory, anti-tumor, and other pharmacological activities, is an important active ingredient extracted from AR. Recently, APS has been increasingly used in cancer therapy owing to its anti-tumor ability as it prevents the progression of prostate, liver, cervical, ovarian, and non-small-cell lung cancer by suppressing tumor cell growth and invasion and enhancing apoptosis. In addition, APS enhances the sensitivity of tumors to antineoplastic agents and improves the body's immunity. This macromolecule has prospects for broad application in tumor therapy through various pathways. In this article, we present the latest progress in the research on the anti-tumor effects of APS and its underlying mechanisms, aiming to provide novel theoretical support and reference for its use in cancer therapy.

Astragalus polysaccharide promotes the regeneration of intestinal stem cells through HIF-1 signalling pathway

Ionizing radiation (IR)-induced intestinal injury is usually accompanied by high lethality. Intestinal stem cells (ISCs) are critical and responsible for the regeneration of the damaged intestine. Astragalus polysaccharide (APS), one of the main active ingredients of Astragalus membranaceus (AM), has a variety of biological functions. This study was aimed to investigate the potential effects of APS on IR-induced intestine injury via promoting the regeneration of ISCs. We have established models of IR-induced intestinal injury and our results showed that APS played great radioprotective effects on the intestine. APS improved the survival rate of irradiated mice, reversed the radiation damage of intestinal tissue, increased the survival rate of intestinal crypts, the number of ISCs and the expression of intestinal tight junction-related proteins after IR. Moreover, APS promoted the cell viability while inhibited the apoptosis of MODE-K. Through organoid experiments, we found that APS promoted the regeneration of ISCs. Remarkably, the results of network pharmacology, RNA sequencing and RT-PCR assays showed that APS significantly upregulated the HIF-1 signalling pathway, and HIF-1 inhibitor destroyed the radioprotection of APS. Our findings suggested that APS promotes the regeneration of ISCs through HIF-1 signalling pathway, and it may be an effective radioprotective agent for IR-induced intestinal injury.

Exploring Natural Products as Radioprotective Agents for Cancer Therapy: Mechanisms, Challenges, and Opportunities

Radiotherapy is an important cancer treatment. However, in addition to killing tumor cells, radiotherapy causes damage to the surrounding cells and is toxic to normal tissues. Therefore, an effective radioprotective agent that prevents the deleterious effects of ionizing radiation is required. Numerous synthetic substances have been shown to have clear radioprotective effects. However, most of these have not been translated for use in clinical applications due to their high toxicity and side effects. Many medicinal plants have been shown to exhibit various biological activities, including antioxidant, anti-inflammatory, and anticancer activities. In recent years, new agents obtained from natural products have been investigated by radioprotection researchers, due to their abundance of sources, high efficiency, and low toxicity. In this review, we summarize the mechanisms underlying the radioprotective effects of natural products, including ROS scavenging, promotion of DNA damage repair, anti-inflammatory effects, and the inhibition of cell death signaling pathways. In addition, we systematically review natural products with radioprotective properties, including polyphenols, polysaccharides, alkaloids, and saponins. Specifically, we discuss the polyphenols apigenin, genistein, epigallocatechin gallate, quercetin, resveratrol, and curcumin; the polysaccharides astragalus, schisandra, and Hohenbuehelia serotina; the saponins ginsenosides and acanthopanax senticosus; and the alkaloids matrine, ligustrazine, and β-carboline. However, further optimization through structural modification, improved extraction and purification methods, and clinical trials are needed before clinical translation. With a deeper understanding of the radioprotective mechanisms involved and the development of high-throughput screening methods, natural products could become promising novel radioprotective agents.

Investigation of the anti-oxidative and anti-inflammatory effects of melatonin on experimental liver damage by radiation

Radiotherapy is one of the inevitable treatment approaches for several types of cancer. We aimed to show the protective and therapeutic effects of daily use of melatonin on liver tissues subjected to a single dose of 10 Gy (gamma-ray) total body radiation. Rats were divided into 6 groups, of which 10 were in each: control, sham, melatonin, radiation, radiation+melatonin, and melatonin+radiation. The rats received 10 Gy of external radiation throughout their entire bodies. The rats were given 10 mg/kg/day of melatonin intraperitoneally before or after radiation treatment, depending on the group. Histological methods, immunohistochemical analysis (Caspase-3, Sirtuin-1, α-SMA, NF_ΚB-p65), biochemical analysis by ELİSA (SOD, CAT, GSH-PX, MDA, TNF-α, TGF-β, PDGF, PGC-1α) and the Comet assay as a marker of DNA damage were applied to the liver tissues. Histopathological examinations showed structural changes in the liver tissue of the radiation group. Radiation treatment increased the immunoreactivity of Caspase-3, Sirtuin-1 and α-SMA, but these effects were relatively attenuated in the melatonin-treated groups. The melatonin+radiation group had statistically significant results close to those of the control group, in terms of Caspase-3, NF_ΚB-p65 and Sirtuin-1 immunoreactivity. In melatonin treated groups, hepatic biochemical markers, MDA, SOD, TNF-α, TGF-β levels, and DNA damage parameters were decreased. Administration of melatonin before and after radiation has beneficial effects, but using it before radiation may be more efficient. Accordingly, daily melatonin usage could mitigate ionizing radiation induced damage.

Protective effects of Yiqi jiedu decoction on ionizing radiation-induced spermatogenic cell injury

ETHNOPHARMACOLOGICAL RELEVANCE

Ionizing radiation (IR) has found widespread application in modern medicine. As a result, radiotherapy inevitably causes spermatogenic cell injury. Many Chinese herbal prescriptions or natural extracts have the potential to protect against radiation injury.

AIM OF THE STUDY

We used GC-2spd cells to investigate the effects and potential mechanisms of YQJD decoction on protecting spermatogenic cells from ionizing radiation injury.

MATERIALS AND METHODS

Firstly, the GC-2spd cells were irradiated with 60Co γ-rays (1 Gy, 2 Gy, 4 Gy and 8 Gy) to establish an in vitro model of radiation injury. After that, Cells were divided into six groups: negative control group (NC group), model group (IR group), positive drug group (IRA group), high-dose YQJD decoction (IRH group), medium-dose YQJD decoction (IRM group), and low-dose YQJD decoction group (IRL group). DNA damage, oxidative damage and inflammatory factors were measured. Cell apoptosis and cell cycle were detected by Flow cytometry. Transmission electron microscopy was performed to observe the morphological changes.

RESULTS

After irradiation with 60CO γ-ray, the results indicated that the damage of spermatocyte was significantly induced by radiation exposure over 4 Gy. Furthermore, ionizing radiation could make DNA damage and oxidative stress in in GC-2spd cells. In addition, 60CO γ-ray also caused the increase of IL-1β, IL-6 and TNF-α and the change of cell cycle. However, the application of YQJD decoction inhibited the damage and apoptosis of GC-2spd cells in the aspects of anti-oxidation, promoting DNA damage repair and regulating inflammatory reaction.

CONCLUSIONS

Taken together, the protective effects of YQJD decoction on 60CO γ-ray induced spermatocyte injury were confirmed in this study. This exploration might provide a new strategy for the application of Chinese herbs in radioprotection.

Deciphering the Efficacy and Mechanism of Astragalus membranaceus on High Altitude Polycythemia by Integrating Network Pharmacology and In Vivo Experiments

Hypoxic exposure makes plateau migrators susceptible to high altitude polycythemia (HAPC). Astragalus membranaceus (AM) is an edible and medicinal plant with remarkable immunomodulatory activities. The purpose of this study was to discover if AM could be a candidate for the prevention of HAPC and its mechanism. Here, network pharmacology was applied to screen active compounds, key targets, and enriched pathways of AM in the treatment of HAPC. Molecular docking evaluated the affinity between compounds and core targets. Subsequently, the mechanisms of AM were further verified using the hypoxia exposure-induced mice model of HAPC. The network pharmacology analysis and molecular docking results identified 14 core targets of AM on HAPC, which were predominantly mainly enriched in the HIF-1 pathway. In the HAPC animal models, we found that AM inhibited the differentiation of hematopoietic stem cells into the erythroid lineage. It also suppressed the production of erythrocytes and hemoglobin in peripheral blood by reducing the expression of HIF-1α, EPO, VEGFA, and Gata-1 mRNA. Furthermore, AM downregulated the expression of IL-6, TNF-α, and IFN-γ mRNA, thereby alleviating organ inflammation. In conclusion, AM supplementation alleviates hypoxia-induced HAPC in mice, and TNF-α, AKT1, HIF-1α, VEGFA, IL-6, and IL-1B may be the key targets.

Targeting p65 to inhibit Cas3 transcription by Onjisaponin B for radiation damage therapy in p65+/- mice

BACKGROUND

In response to radiation injury, p65 becomes activated. The formation of p65 is one target of Onjisaponin B (OB), but it has not been studied in radioprotection. In addition, there is a binding site for p65 in the promoter region of Cas3. This study evaluates the use of OB as an intervention to modulate p65/Cas3 following radiation exposure.

PURPOSE

This study aimed to confirm that OB regulated the transcription of Cas3 via p65 to overcome radiation-induced damage.

STUDY DESIGN AND METHODS

Cells and mice were exposed to X-rays at a dose of 6 Gy. Immunofluorescence was used to locate intracellular p65. For the protein and mRNA analyses, Western blotting and RT-qPCR-based assays were conducted accordingly. HE staining was used to observe pathological changes in tissues. DNA damage was detected by the comet assay and DNA ladder assay. Next, apoptosis was detected by flow cytometry and Hoechst staining.

RESULTS

Compared with the radiation group, the expression levels of p-p65 and c-Cas3 in the drug group were significantly down-regulated by OB 20 µg/ml. When the expression of p65 was suppressed in V79 and TC cells, OB did not significantly inhibit the activation of p65 or Cas3 in response to irradiation, nor did it significantly inhibit the phosphorylation of p65 and subsequent nuclear translocation. Overexpression of p65 in V79 and MTEC-1 cells resulted in OB significantly inhibiting the activation of p65 and Cas3, and the phosphorylation and translocation of p65 into the nucleus. At 3 d for V79 cells and 24 h for MTEC-1 cells after radiation, compared with the Cas3 over plasmid transfection group, the drug transfection group had no significant effect on reducing apoptosis. In p65+/- mice, expression of the p65 gene was knocked down, leading to increased tissue apoptosis and inflammation, and serious tissue pathological changes. The inhibition of p65 activation by OB after radiation exposure was not apparent in the thymus, although it was observed in the lung.

CONCLUSIONS

OB interfered with radiation injury by targeting and regulating p65/Cas3. Therefore, it has been concluded that p65 is an important target molecule for the treatment of radiation injury.

Astragalus Polysaccharide Protects Against Cadmium-Induced Autophagy Injury Through Reactive Oxygen Species (ROS) Pathway in Chicken Embryo Fibroblast

Cadmium (Cd) is a harmful heavy metal pollutant, which can cause oxidative stress in the body and induce cell damage. Reactive oxygen species (ROS) is a general term for substances that contain oxygen and are active in the body. However, excessive ROS can damage the body. Cadmium poisoning can cause a large amount of ROS in cells and autophagy. Astragalus polysaccharide (APS) is a plant polysaccharide with biological functions, such as antioxidant and anti-stress activities. In this study, chicken embryo fibroblasts (CEF) were used to determine the relationship between ROS and autophagy damage of Cd-infected cells and the mechanism of APS on cadmium-induced autophagy damage. The results showed that a 10-μL dose of 10 μmol/L cadmium chloride (CdCl₂) can induce CEF autophagy and damage when CEF was added for 36 h. Cadmium induced CEF autophagy damage by increasing ROS production. APS could significantly reduce ROS production and LC3-II and Beclin-1 protein expression, increase the expression of mTOR and the level of antioxidation, and restore the viability and morphological damage of CEF exposed to Cd. Our study suggests that APS can alleviate Cd-induced CEF autophagy damage by reducing the production of ROS.

The Current Application and Future Prospects of Astragalus Polysaccharide Combined With Cancer Immunotherapy: A Review

So far, immunotherapy has been shown to have impressive effects on different cancers in clinical trials. All those immunotherapies are generally derived from three main therapeutic approaches: immune checkpoint inhibitors, immune cell vaccination, and adoptive cellular immunotherapy. Our research systematically reviewed a wide range of clinical trials and laboratory studies of astragalus polysaccharide (APS) and elucidated the potential feasibility of using APS in activating adoptive immunotherapy. Apart from being effective in adaptive “passive” immunotherapy such as lymphokine-activated killer treatment and dendritic cell (DC)–cytokine–induced killer treatment, APS could also regulate the anti-programmed cell death protein 1 (PD-1)/PD-L1 on the surface of the immune cells, as a part in the immune checkpoint inhibitory signaling pathway by activating the immune-suppressed microenvironment by regulating cytokines, toll-like receptor 4 (TLR4), nuclear factor kappa B (NF-κB), and mitogen-activated protein kinase (MAPK) pathways, and immune cells, such as DCs, macrophages, NK cells, and so on. In view of the multiple functions of APS in immunotherapy and tumor microenvironment, a combination of APS and immunotherapy in cancer treatment has a promising prospect.

Radiation-induced liver injury and hepatocyte senescence

Radiation-induced liver injury (RILI) is a major complication of radiotherapy during treatment for liver cancer and other upper abdominal malignant tumors that has poor pharmacological therapeutic options. A series of pathological changes can be induced by radiation. However, the underlying mechanism of RILI remains unclear. Radiation can induce cell damage via direct energy deposition or reactive free radical generation. Cellular senescence can be observed due to the DNA damage response (DDR) caused by radiation. The senescence-associated secretory phenotype (SASP) secreted from senescent cells can cause chronic inflammation and aggravate liver dysfunction for a long time. Oxidative stress further activates the signaling pathway of the inflammatory response and affects cellular metabolism. miRNAs clearly have differential expression after radiation treatment and take part in RILI development. This review aims to systematically profile the overall mechanism of RILI and the effects of radiation on hepatocyte senescence, laying foundations for the development of new therapies.

Effects of radiation and role of plants in radioprotection: A critical review

Radiation can be lethal at high doses, whereas controlled doses are useful in medical applications. Other applications include power generation, agriculture sterilization, nuclear weapons, and archeology. Radiation damages genetic material, which is reflected in genotoxicity and can cause hereditary damage. In the medical field, it is essential to avoid the harmful effects of radiation. Radiation countermeasures and the need for radioprotective agents have been explored in recent years. Considering plants that evolve in radiative conditions, their ability to protect organisms against radiation has been studied and demonstrated. Crude extracts, fractioned extracts, isolated phytocompounds, and plant polysaccharides from various plants have been used in radioprotection studies, and their efficiency has been proven in various in vitro and in vivo experimental models. It is important to identify the mechanism of action to develop a potent plant-based radioprotective agent. To identify this protective mechanism, it is necessary to understand the damage caused by radiation in biological systems. This review intends to discuss the effects of ionizing radiation on biological systems and evaluate plant-based radioprotectants that have tested thus far as well as their mechanism of action in protecting against the toxic effects of radiation. From the review, the mechanism of radioprotection exhibited by the plant-based products could be understood. Meanwhile, we strongly suggest that the potential products identified so far should undergo clinical trials for critically evaluating their effects and for developing an ideal and compatible radioprotectant with no side-effects.

Review of the Efficacy and Mechanisms of Traditional Chinese Medicines as a Therapeutic Option for Ionizing Radiation Induced Damage

Ionizing radiation damage refers to acute, delayed, or chronic tissue damage associated with ionizing radiation. Specific or effective therapeutic options for systemic injuries induced by ionizing radiation have not been developed. Studies have shown that Chinese herbal Medicine or Chinese Herbal Prescription exhibit preventive properties against radiation damage. These medicines inhibit tissue injuries and promote repair with very minimal side effects. This study reviews traditional Chinese herbal medicines and prescriptions with radiation protective effects as well as their mechanisms of action. The information obtained will guide the development of alternative radioprotectants.

Potential of natural products as radioprotectors and radiosensitizers: opportunities and challenges

Natural products can be used as natural radiosensitizers and radioprotectors, showing promising effects in cancer treatments in combination with radiotherapy, while reducing ionizing radiation (IR) damage to normal cells/tissues. The different effects of natural products on irradiated normal and tumor cells/tissues have attracted more and more researchers' interest. Nonetheless, the clinical applications of natural products in radiotherapy are few, which may be related to their low bioavailability in the human body. Here, we displayed the radiation protection and radiation sensitization of major natural products, highlighted the related molecular mechanisms of these bioactive substances combined with radiotherapy to treat cancer, and critically reviewed their deficiency and improved measures. Lastly, several clinical trials were presented to verify the clinical application of natural products as radiosensitizers and radioprotectors. Further clinical evaluation is still needed. This review provides a reference for the utilization of natural products as radiosensitizers and radioprotectors.

Natural Drugs as a Treatment Strategy for Cardiovascular Disease through the Regulation of Oxidative Stress

Oxidative stress (OS) refers to the physiological imbalance between oxidative and antioxidative processes leading to increased oxidation, which then results in the inflammatory infiltration of neutrophils, increased protease secretion, and the production of a large number of oxidative intermediates. Oxidative stress is considered an important factor in the pathogenesis of cardiovascular disease (CVD). At present, active components of Chinese herbal medicines (CHMs) have been widely used for the treatment of CVD, including coronary heart disease and hypertension. Since the discovery of artemisinin for the treatment of malaria by Nobel laureate Youyou Tu, the therapeutic effects of active components of CHM on various diseases have been widely investigated by the medical community. It has been found that various active CHM components can regulate oxidative stress and the circulatory system, including ginsenoside, astragaloside, and resveratrol. This paper reviews advances in the use of active CHM components that modulate oxidative stress, suggesting potential drugs for the treatment of various CVDs.

Astragali Radix (Huangqi): A promising edible immunomodulatory herbal medicine

ETHNOPHARMACOLOGICAL RELEVANCE

Astragali Radix (AR, Huangqi in Chinese), the dried root of Astragalus membranaceus (Fisch.) Bge. var. mongholicus (Bge.) Hsiao or A. membranaceus (Fisch.) Bge., possesses diverse therapeutic effects against fatigue, dyspepsia, diarrhea, heart diseases, hepatitis, and anemia. In recent years, increasing evidence has indicated the multiple immunomodulatory activities of AR in preclinical and clinical studies.

AIM OF THE REVIEW

This review attempts to elaborate the immunomodulatory effects of AR and its potential application in the treatment of immune related diseases.

MATERIALS AND METHODS

A comprehensive literature search AR was carried out using multiple internationally recognized databases (including Web of Science, Google Scholar, PubMed, ScienceDirect, Wiley, ACS, Springer, Taylor & Francis, and CNKI).

RESULTS

The immunomodulatory effects of AR are closely attributed to its active constituents such as polysaccharides, saponins, and flavonoids. We also demonstrate that AR can be used as a potential therapeutic intervention for immune related diseases through regulating immune organs, mucosal immune, and immune system (innate immunity and acquired immunity).

CONCLUSION

AR promotes the development of immune organs, enhances mucosal immune function, increases the quantity and phagocytic capacity of innate immunity, promotes the maturation and differentiation of acquired immunity cells, and improves the expression of antibodies in acquired immunity. We believe that AR has a broad research space in the adjuvant treatment of immune related diseases, which could be a breakthrough point to improve the application value of AR.

Radioprotective effects and mechanisms of animal, plant and microbial polysaccharides

Ionizing radiation is increasingly used to successfully diagnose many human health problems, but ionizing radiation may cause damage to organs/tissues in the living organisms such as the spleen, liver, skin, and brain. Many radiation protective agents have been discovered, with the deepening of radiation research. Unfortunately, these protective agents have many side effects, which cause drug resistance, nausea, vomiting, osteoporosis, etc. The polysaccharides extracted from natural sources are widely available and low in toxicity. In vivo and in vitro experiments have demonstrated that polysaccharides have anti-radiation activity through anti-oxidation, immune regulation, protection of hematopoietic system and protection against DNA damage. Recently, some studies have shown that polysaccharides were resistant to radiation. In the review, the anti-radiation activities of polysaccharides from different sources are summarized, and the anti-radiation mechanisms are discussed as well. It can be used to develop more effective anti-radiation management drugs.

A Chinese herbal prescription Yiqi Jiedu decoction attenuates irradiation induced testis injury in mice

OBJECTIVE

Yiqi Jiedu (YQJD) decoction is a Chinese herbal prescription, based on an experienced expert of traditional Chinese medicine. It is used for the injuries caused by radiotherapy. The current study was designed to investigate the protective effects of YQJD decoction on radiation damage of testis in mice, and to explore its potential mechanisms.

METHODS

Mice were randomly divided into blank control group (Ctrl), model group (IR), positive drug group (IRA), and YQJD decoction group (IRY). After 10-day period intervention, they were whole-body irradiated with 2 Gy ⁶⁰Co γ-rays and sacrificed on 7^th day after irradiation. The indicators including the index and histopathology examination of testis, spermatogenic cell types and apoptosis, and the expression of TLR5, MyD88, NF-κB, TNF-α, IL-6 and Bcl-2 in testis.

RESULTS

The testis atrophied significantly on 7^th day of exposure to radiation, while YQJD decoction promoted the recovery of testis index and structure. Moreover, spermatogenic cell types and apoptosis had significant changes after irradiation. YQJD decoction protected the testicular function of spermatogenesis, as while as reduced the apoptosis rate of spermatogenic cells. In addition, RT-PCR and immunohistochemical analysis showed that YQJD decoction up-regulated the expression of TLR5 in testis. The levels of TLR5's downstream factors were also up-regulated in YQJD decoction group, which indicated that TLR5 signaling pathway might play an important role in the protective effects of YQJD decoction.

CONCLUSIONS

The results showed that YQJD decoction attenuated irradiation induced testis injury in mice. Its potential mechanism was related to TLR5 signaling pathway.

The effects of Astragalus Membranaceus Active Extracts on Autophagy-related Diseases

Autophagy is an evolutionarily conserved 'self-eating' process that maintains cellular, tissue, and organismal homeostasis. New studies on autophagy, mediated by subsets of autophagy proteins, are emerging in many physiological and pathological processes. Astragalus membranaceus (AM), also named Huangqi, is one of the fundamental herbs in traditional Chinese medicine and its extracts have been proved to possess many biological activities related to autophagy, including anti-oxidation, anti-inflammation, anticancer, anti-photoaging, and improvement of cardiomyocyte function. Evidence suggests that AM extracts can have therapeutic potential in autophagy dysregulation-associated diseases because of their biological positive effects. Here we will review the literature concerning the effects of AM extracts on autophagy dysregulation-associated diseases.

Astragalus polysaccharides alleviate tilmicosin-induced toxicity in rats by inhibiting oxidative damage and modulating the expressions of HSP70, NF-kB and Nrf2/HO-1 pathway

The present study evaluated the toxic effects of Tilmicosin (TIL) on adult rats. The rats received a single subcutaneous injection of TIL at different doses (10, 25, 50, 75 and 100 mg/kg bw). TIL altered the biochemical parameters including liver and kidney function markers, glucose level and lipid profile as well as resulted in histopathological lesions in liver and adrenal glands mostly in rats exposed to 75 and 100 mg/kg bw. Then the role of Astragalus polysaccharide (APS) at 100 and 200 mg/kg bw, in modulating the toxic effects induced by high dose of TIL was evaluated. Single injection of TIL at a dose of 75 mg/kg bw was found to increase the activity of ALT, AST and ALP enzymes, induce the generation of reactive oxygen species (ROS) and decrease the total antioxidant capacity (TAC). TIL upregulated the hepatic mRNA expression of heat shock protein 70 (HSP70) and nuclear factor kappa B (NF-kB) while blocked the Nrf2/HO-1 mediated response. These changes were also associated with increasing tumer necrosis factor-alpha (TNF-α), interlukin1-beta (IL-1β) and nitric oxide levels. On the other hand, the results indicate that APS has a beneficial role particularly at high level in alleviating the stress and the hepatotoxic effects elicited by TIL injection in rats.

Metabolomics Research Reveals the Mechanism of Action of Astragalus Polysaccharide in Rats with Digestive System Disorders

With the diversity of modern dietary lifestyles, digestive system disorders (DSD) have become a frequently occurring disease in recent years. Astragalus polysaccharide (APS) is a homogeneous polysaccharide extracted from Astragalus, which might ameliorate the digestive and absorptive functions. However, the treatment mechanisms remain unclear. In this study, rats with DSD were fed a high-fat⁻low-protein diet and subjected to weight-bearing swimming until exhaustion. When body weight and autonomous activities of the rats decreased, they were administered APS. After two weeks, serum metabolomics analysis based on LC-MS was performed to validate the therapeutic effect of APS and explore its mechanism. APS pharmacodynamics was determined in this study, and serum metabolomics analysis discovered and identified 16 significant, differentially produced metabolites involved in energy, amino acid, and lipid metabolism, including citric acid, lactic acid, alanine, phosphatidylcholine, phenylalanine. After treatment with APS, the levels of the above small-molecule metabolites were reversed. Our results show the efficacy of APS in DSD treatment through the regulation of perturbed metabolic pathways related to energy, amino acid, and lipid metabolism.

Astragalus polysaccharides decrease proliferation, migration, and invasion but increase apoptosis of human osteosarcoma cells by up-regulation of microRNA-133a

Osteosarcoma (OS) has a high incidence, malignity, and frequency of recurrence and metastasis. In this study, we aimed to explore the potential anti-cancer effects of Astragalus polysaccharides (APS) on human OS MG63 cells as well as underlying mechanisms. Viability of MG63 cells was assessed by CCK-8 assay to determine the adequate concentration of APS. Then, effects of APS on MG63 cell proliferation, cell cycle distribution, apoptosis, and migration and invasion were analyzed by BrdU incorporation, PI staining, flow cytometry, and transwell assays, respectively. The expression levels of proteins involved in these physiological processes were assessed by western blot analysis. Afterwards, miR-133a level in APS-treated cells was determined by qRT-PCR, and whether APS affected MG63 cells through regulation of miR-133a was determined. Finally, the activation of c-Jun N-terminal protein kinase (JNK) pathway was detected. We found that APS treatment suppressed the viability, proliferation, migration, and invasion of MG63 cells, as well as induced cell apoptosis. Moreover, APS enhanced the expression of miR-133a in MG63 cells. Knockdown of miR-133a reversed the APS treatment-induced MG63 cell proliferation, migration and invasion inhibition, as well as cell apoptosis. Furthermore, APS inactivated JNK pathway in MG63 cells. Knockdown of miR-133a reversed the APS treatment-induced inactivation of JNK pathway in MG63 cells. To conclude, APS repressed proliferation, migration, and invasion while induced apoptosis of OS MG63 cells by up-regulating miR-133a and then inactivating JNK pathway.

Astragalus polysaccharide combined with 10-hydroxycamptothecin inhibits metastasis in non-small cell lung carcinoma cell lines via the MAP4K3/mTOR signaling pathway

Non‑small cell lung carcinoma (NSCLC) is a life‑threatening malignancy. The level of the cell growth regulator mitogen‑activated protein kinase kinase kinase kinase 3 (MAP4K3) has been shown to be correlated with a high risk of NSCLC recurrence and poor recurrence‑free survival rate. The present study examined the effects of Astragalus polysaccharide (APS) and 10‑hydroxycamptothecin (HCPT), which are associated with marked suppression and dephosphorylation of the MAP4K3/mammalian target of rapamycin (mTOR) signaling pathway, in the H1299 NSCLC cell line. APS and HCPT decreased H1299 cell viability, induced apoptosis and altered the cell cycle stages, as evaluated using an 3‑(4,5‑dimethylthiazol‑2‑yl)‑2,5‑diphenyltetrazolium bromide assay and flow cytometric analysis. Furthermore, APS increased the expression of apoptosis‑associated genes B‑cell lymphoma 2 (Bcl‑2) and Bcl‑2‑associated X protein (BAX), of proteases cysteine‑aspartic acid protease (caspase)‑3 and ‑9, and of cytochrome c. HCPT promoted autophagy in H1299 cells, with concomitant suppression of the expression of MAP4K3 and downregulation of mTOR signaling. Notably, combination treatment with the two agents reduced the migration and invasion of H1299 cells compared with the single treatments. It was also demonstrated that the overexpression of MAP4K3 promoted the migration and invasion of H1299 cells, and that the kinase activity was essential to this. These findings suggested that MAP4K3 may be an attractive target for the treatment of NSCLC.

Astragalus Polysaccharide Protects Neurons and Stabilizes Mitochondrial in a Mouse Model of Parkinson Disease

BACKGROUND Astragalus polysaccharides (APS) have a very good therapeutic effect in the treatment of neurodegenerative diseases and nerve injury disease. However, research on Parkinson disease (PD) treatment with APS is lacking. MATERIAL AND METHODS The present study was designed to explore the effects of APS on the protection of neurons and mitochondrial in a mouse model of PD using behavioral experiments, and observations of mitochondrial structure and transmembrane potential. RESULTS It was shown that APS could attenuate 1-methyl-4-pheyl-1,2,3,6-tetrahydropyridine (MPTP)-induced motor dysfunction (P<0.01), increase the proportion of TH-positive cells (P<0.01), reverse MPTP-induced mitochondrial structural damage, and reduce MPTP-induced high levels of reactive oxygen species (ROS) and increase MPTP-induced decrease in mitochondrial membrane potential. In addition, APS also decreased the bax/bcl2 ratio, and cytochrome-c and caspase-3 protein content (P<0.01) in substantia nigra in our mouse PD model. CONCLUSIONS APS provided a protective effect on neurons and mitochondrial in a mouse PD model.

Seabuckthorn berry polysaccharide protects against carbon tetrachloride-induced hepatotoxicity in mice via anti-oxidative and anti-inflammatory activities

The berries of Seabuckthorn (Hippophae rhamnoides L.) are traditional medicinal foods that have been used by Tibetans and Mongolians for thousands of years. The polysaccharides are the main components of Seabuckthorn berries, possessing immune stimulating, anti-cancer and anti-fatigue activities. The present study focused on evaluating the protective effects and mechanisms of Seabuckthorn berry polysaccharide (SP) against carbon tetrachloride (CCl₄)-induced hepatotoxicity. Mice were orally administrated with 50, 100 and 200 mg kg^-1 of SP once daily for 14 consecutive days prior to CCl₄ challenge. Pretreatment with SP significantly decreased alanine transaminase (ALT), aspartate aminotransferase (AST) and total bilirubin (TBIL) levels, while increasing the levels of prealbumin (PALB) in the CCl₄-challenged mice, which were accompanied by diminished liver injuries, increased superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities, increased GSH levels, and reduced malondialdehyde (MDA) content. The pretreatment with SP also markedly reduced the CCl₄-induced expression of tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), inducible nitric oxide synthase (iNOS) and nitric oxide (NO). Furthermore, the pretreatment with SP decreased hepatic Toll-like receptor 4 (TLR4) expression and inhibited the phosphorylation of p38 MAPK, extracellular signal-regulated kinase (p-ERK), c-Jun N-terminal kinase (p-JNK) and nuclear factor-kappa B (NF-κB) in the CCl₄-challenged mice. These results suggest that the pretreatment with SP protected against CCl₄-induced liver damage via its anti-oxidative and anti-inflammatory activities. SP might be suitable for functional foods and natural drugs in preventing CCl₄-induced hepatotoxicity.

Astragalus Polysaccharide Protect against Cadmium-Induced Cytotoxicity through the MDA5/NF-κB Pathway in Chicken Peripheral Blood Lymphocytes

Cadmium (Cd) is a known environmental pollutant that is associated with inflammation, oxidative stress, and cell apoptosis. Astragalus polysaccharide (APS) is a major component of Astragalus membranaceus, a vital qi-reinforcing herb medicine with favorable immuneregulation properties. To study the effect of APS on the inhibition of the cadmium-induced injury of peripheral blood lymphocytes (PBLs) in chickens through the MDA5/NF-κB signaling pathway, PLBs acquired from 15-day-old chickens were divided into control group, Cd group, APS + Cd group, anti-MDA5 mAb + Cd group, BAY 11-7082 (a nuclear factor kappa-light chain-enhancer of activated B cells [NF-κB] inhibitor) +Cd group, APS group, anti-MDA5 mAb group, and BAY 11-7082 group. The transcription levels of melanoma differentiation-associated gene 5 (MDA5), interferon promoter-stimulating factor 1 (IPS-1), NF-κB, and inflammatory factors tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 were measured by quantitative real-time PCR. MDA5 protein expression was measured by western blotting. Levels of malondialdehyde (MDA), glutathione peroxidase (GSH-Px), and superoxide dismutase (SOD) were measured by corresponding antioxidant kit. The morphological change of PBLs was measured by transmission electron microscopy. The results showed that Cd significantly increased the expression of MDA5, IPS-1, NF-κB, and their downstream cytokines, IL-1β and TNF-α, IL-6 in PLBs. In addition, a high level of MDA was observed in the Cd treatment group; the activities of GSH-Px and SOD were significantly lower in the Cd treatment group than those in controls (p < 0.05). Ultrastructural changes of PBLs showed that Cd promoted autophagy, apoptosis, and necrosis in PBLs. However, APS can efficiently improve Cd-induced cell damage by decreasing the activation of the MDA5 signaling pathway. The effect is consistent with that of anti-MDA5 mAb or/and BAY. The results indicated that APS inhibited Cd-induced cytotoxicity through the regulation of MDA5/NF-κB signaling.

The effect of Astragalus polysaccharides on attenuation of diabetic cardiomyopathy through inhibiting the extrinsic and intrinsic apoptotic pathways in high glucose -stimulated H9C2 cells

Background

Apoptosis plays a critical role in the progression of diabetic cardiomyopathy (DC). Astragalus polysaccharides (APS), an extract of astragalus membranaceus (AM), is an effective cardioprotectant. Currently, little is known about the detailed mechanisms underlying cardioprotective effects of APS. The aims of this study were to investigate the potential effects and mechanisms of APS on apoptosis employing a model of high glucose induction of apoptosis in H9C2 cells.

Methods

A model of high glucose induction of H9C2 cell apoptosis was adopted in this research. The cell viabilities were analyzed by MTT assay, and the apoptotic response was quantified by flow cytometry. The expression levels of the apoptosis related proteins were determined by Real-time PCR and western blotting.

Results

Incubation of H9C2 cells with various concentrations of glucose (i.e., 5.5, 12.5, 25, 33 and 44 mmol/L) for 24 h revealed that cell viability was reduced by high glucose dose-dependently. Pretreatment of cells with APS could inhibit high glucose-induced H9C2 cell apoptosis by decreasing the expressions of caspases and the release of cytochrome C from mitochondria to cytoplasm. Further experiments also showed that APS could modulate the ratio of Bcl-2 to Bax in mitochondria.

Conclusions

APS decreases high glucose-induced H9C2 cell apoptosis by inhibiting the expression of pro-apoptotic proteins of both the extrinsic and intrinsic pathways and modulating the ratio of Bcl-2 to Bax in mitochondria.

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.

Astragalus polysaccharides protect against dextran sulfate sodium-induced colitis by inhibiting NF-κВ activation

Astragalus polysaccharide (APS) is a bioactive extract of Astragalus membranaceus (AM), which possess a wide range of medicinal benefits, including anti-inflammatory, anti-oxidative, anti-tumor and anti-diabetic effects. The present work evaluated the therapeutic effect of APS and its potential mechanisms in a mouse model of dextran sulfate sodium (DSS)-induced colitis. The APS treatment led to significant improvements in colitis disease activity index (DAI) and histological scores, as well as significantly increased weight and colon length in mice as compared to the control group. Mechanically, reduced NF-κВ DNA phosphorylation activity and downregulated TNF-α, IL-1β, IL-6, IL-17 expressions and myeloperoxidase (MPO) activity were associated with improvement in colitis observed in APS-treated mice. These findings suggest that APS may represent a natural therapeutic approach for treating inflammatory bowel disease, such as ulcerative colitis.

Polysaccharides from Traditional Chinese Medicines: Extraction, Purification, Modification, and Biological Activity

Traditional Chinese Medicine (TCM) has been used to treat diseases in China for thousands of years. TCM compositions are complex, using as their various sources plants, animals, fungi, and minerals. Polysaccharides are one of the active and important ingredients of TCMs. Polysaccharides from TCMs exhibit a wide range of biological activities in terms of immunity- modifying, antiviral, anti-inflammatory, anti-oxidative, and anti-tumor properties. With their widespread biological activities, polysaccharides consistently attract scientist's interests, and the studies often concentrate on the extraction, purification, and biological activity of TCM polysaccharides. Currently, numerous studies have shown that the modification of polysaccharides can heighten or change the biological activities, which is a new angle of polysaccharide research. This review highlights the current knowledge of TCM polysaccharides, including their extraction, purification, modification, and biological activity, which will hopefully provide profound insights facilitating further research and development.

The cytotoxicity and protective effects of Astragalus membranaceus extracts and butylated hydroxyanisole on hydroxyl radical-induced apoptosis in fish erythrocytes

Erythrocytes play an essential role in transporting O₂ and CO₂ for respiration in fish. However, erythrocytes continuously suffer from reactive oxygen species (ROS) -induced oxidative stress and apoptosis. Thus, it is essential to expand our knowledge of how to protect erythrocytes against ROS-induced oxidative stress and apoptosis in fish. In this study, we explored the cytotoxicity and the effects of butylated hydroxyanisole (BHA), ethyl ether extracts, ethyl acetate extracts, acetone extracts (AE), ethanol extracts, and aqueous extracts of Astragalus membranaceus (EAm) on hydroxyl radical (•OH)-induced apoptosis in carp erythrocytes. The rat hepatocytes and carp erythrocytes were incubated with different concentrations of BHA or EAm(0.125 to 1 mg/mL). The toxicity in rat hepatocytes and carp erythrocytes was then measured using a 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay and a haemolysis assay, respectively. The carp erythrocytes were treated with BHA or EAm in the presence of 40 μmol/L FeSO₄ and 20 μmol/L H₂O₂ at 37 °C, except for the control group. Oxidative stress and apoptosis parameters in the carp erythrocytes were then evaluated using the commercial kit. The results indicated that at high concentrations, BHA and EAm could induce toxicity in rat hepatocytes and fish erythrocytes. However, BHA was more toxic than EAm at the same concentrations. Moreover, the toxicity order of BHA and EAm in the fish erythrocytes approximately agreed with that for the rat hepatocytes. Butylated hydroxyanisole and EAm suppressed the •OH-induced phosphatidylserine exposure and DNA fragmentation (the biomarkers of apoptosis) by decreasing the generation of ROS, inhibiting the oxidation of cellular components, and restoring the activities of antioxidants in carp erythrocytes. Of all of the examined EAm, the AE showed the strongest effects. The effects of AE on superoxide anion, H₂O₂, met-haemoglobin and reduced glutathione levels, as well as glutathione reductase activity and apoptosis were equivalent to or stronger than those of BHA. These results revealed that the AE of Astragalus membranaceus could be used as a potential natural antioxidant or apoptosis inhibitor in fish erythrocytes.

Astragalus polysaccharides decrease muscle wasting through Akt/mTOR, ubiquitin proteasome and autophagy signalling in 5/6 nephrectomised rats

ETHNOPHARMACOLOGICAL RELEVANCE

Existing evidences suggest that Radix Astragali and its polysaccharides composition (APS) can improve muscle mass, but the mechanisms need more research.

AIM OF THE STUDY

In this study, we aimed to examine the effects of APS on muscle wasting at molecular level in 5/6 nephrectomised rats.

MATERIALS AND METHODS

We performed 5/6 nephrectomy or sham operation in 160 6-week-old Sprague-Dawley rats, and feed animals with or without 2% APS for 155 days. After treatment, we compared the change of weight, muscle fibre, protein metabolism, pro-inflammatory factors (TNF-α, IL-15, CRP) and oxidative factors (MDA, SOD) among each group. In addition, we detected the Akt/mTOR, ubiquitin proteasome, autophagy signalling and AA transporters in vivo and in vitro.

RESULTS

Data in vivo show 2% APS could alleviate weight loss and improve protein metabolism in nephrectomised rats. The levels of serum pro-inflammatory factors and oxidative factors were restored by APS treatment. In molecular levels, APS restored Akt/mTOR, MAFbx, MuRF1, Atg7, LC3B-II/LC3B-I and SLC38A2 which changed in nephrectomised rats. Data in vitro show the optimal dose of APS is 0.2mg/mL, and SLC38A2 siRNA attenuated the effects of 0.2mg/mL APS on atrophy and autophagy.

CONCLUSIONS

Our results suggested APS could improve muscle wasting through Akt/mTOR, ubiquitin proteasome and autophagy signalling, and SLC38A2 may be one of potential targets.

Recent Advances in Traditional Chinese Medicine for Kidney Disease

Because current treatment options for chronic kidney disease (CKD) are limited, many patients seek out alternative therapies such as traditional Chinese medicine. However, there is a lack of evidence from large clinical trials to support the use of traditional medicines in patients with CKD. Many active components of traditional medicine formulas are undetermined and their toxicities are unknown. Therefore, there is a need for research to identify active compounds from traditional medicines and understand the mechanisms of action of these compounds, as well as their potential toxicity, and subsequently perform well-designed, randomized, controlled, clinical trials to study the efficacy and safety of their use in patients with CKD. Significant progress has been made in this field within the last several years. Many active compounds have been identified by applying sophisticated techniques such as mass spectrometry, and more mechanistic studies of these compounds have been performed using both in vitro and in vivo models. In addition, several well-designed, large, randomized, clinical trials have recently been published. We summarize these recent advances in the field of traditional medicines as they apply to CKD. In addition, current barriers for further research are also discussed. Due to the ongoing research in this field, we believe that stronger evidence to support the use of traditional medicines for CKD will emerge in the near future.

Mechanisms of cardiac radiation injury and potential preventive approaches

In addition to cytostatic treatment and surgery, the most common cancer treatment is gamma radiation. Despite sophisticated radiological techniques however, in addition to irradiation of the tumor, irradiation of the surrounding healthy tissue also takes place, which results in various side-effects, depending on the absorbed dose of radiation. Radiation either damages the cell DNA directly, or indirectly via the formation of oxygen radicals that in addition to the DNA damage, react with all cell organelles and interfere with their molecular mechanisms. The main features of radiation injury besides DNA damage is inflammation and increased expression of pro-inflammatory genes and cytokines. Endothelial damage and dysfunction of capillaries and small blood vessels plays a particularly important role in radiation injury. This review is focused on summarizing the currently available data concerning the mechanisms of radiation injury, as well as the effectiveness of various antioxidants, anti-inflammatory cytokines, and cytoprotective substances that may be utilized in preventing, mitigating, or treating the toxic effects of ionizing radiation on the heart.

A strategy for effective radioprotection by chitosan-based long-circulating nanocarriers

Effective radioprotection is achieved by chitosan-based long-circulating nanocarriers with radioprotective agents. The stable encapsulation does not reduce its radioprotective capability and exhibits prolonged retention time, thereby showing more beneficial effects.