Activates B lymphocytes and enhanced immune response: A promising adjuvant based on PLGA nanoparticle to improve the sensitivity of ZEN monoclonal antibody

In preparing monoclonal antibodies by hybridoma cell technology, the quality of B lymphocytes used for cell fusion directly affects the sensitivity of monoclonal antibodies. To obtain B-lymphocytes producing high-quality specific antibodies for cell fusion during the immunization phase of the antigen, we prepared a TH2-Cell stimulatory delivery system as a novel adjuvant. Astragalus polysaccharide has a good ability to enhance antigenic immune response, and it was encapsulated in biocompatible materials PLGA as an immunostimulatory factor to form the delivery system (APS-PLGA). The preparation conditions of APSP were optimized using RSM to attain the highest utilization of APS. Immunization against ZEN-BSA antigen using APSP as an adjuvant to obtain B lymphocytes producing ZEN-specific antibodies for cell fusion. As results present, APSP could induce a stronger TH2 immune response through differentiating CD4 T cells and promoting IL-4 and IL-6 cytokines. Moreover, it could slow down the release efficiency of ZEN-BSA and enhance the targeting of ZEN-BSA to lymph nodes in vivo experiments. Ultimately, the sensitivity of mouse serum ZEN-specific antibodies was enhanced upon completion of immunization, indicating a significant upregulation of high-quality B lymphocyte expression. In the preparation of monoclonal antibodies, the proportion of positive wells for the first screening was 60%, and the inhibition rates of the antibodies were all similar (>50%). Then we obtained the ZEN monoclonal antibody with IC50 of 0.049 ng/mL, which was more sensitive than most antibodies prepared under conventional adjuvants. Finally, a TRFIAS strip assay was preliminarily established with a LOD value of 0.246 ng/mL.

Astragalus Polysaccharide Enhances Voriconazole Metabolism under Inflammatory Conditions through the Gut Microbiota

Background and Aims

Voriconazole (VRC), a widely used antifungal drug, often causes hepatotoxicity, which presents a significant clinical challenge. Previous studies demonstrated that Astragalus polysaccharide (APS) can regulate VRC metabolism, thereby potentially mitigating its hepatotoxic effects. In this study, we aimed to explore the mechanism by which APS regulates VRC metabolism.

Methods

First, we assessed the association of abnormal VRC metabolism with hepatotoxicity using the Roussel Uclaf Causality Assessment Method scale. Second, we conducted a series of basic experiments to verify the promotive effect of APS on VRC metabolism. Various in vitro and in vivo assays, including cytokine profiling, immunohistochemistry, quantitative polymerase chain reaction, metabolite analysis, and drug concentration measurements, were performed using a lipopolysaccharide-induced rat inflammation model. Finally, experiments such as intestinal biodiversity analysis, intestinal clearance assessments, and Bifidobacterium bifidum replenishment were performed to examine the ability of B. bifidum to regulate the expression of the VRC-metabolizing enzyme CYP2C19 through the gut-liver axis.

Results

The results indicated that APS does not have a direct effect on hepatocytes. However, the assessment of gut microbiota function revealed that APS significantly increases the abundance of B. bifidum, which could lead to an anti-inflammatory response in the liver and indirectly enhance VRC metabolism. The dual-luciferase reporter gene assay revealed that APS can hinder the secretion of pro-inflammatory mediators and reduce the inhibitory effect on CYP2C19 transcription through the nuclear factor-κB signaling pathway.

Conclusions

The study offers valuable insights into the mechanism by which APS alleviates VRC-induced liver damage, highlighting its immunomodulatory influence on hepatic tissues and its indirect regulatory control of VRC-metabolizing enzymes within hepatocytes.

Astragalus polysaccharides augment BMSC homing via SDF-1/CXCR4 modulation: a novel approach to counteract peritoneal mesenchymal transformation and fibrosis

PURPOSE

This study aimed to evaluate the potential of astragalus polysaccharide (APS) pretreatment in enhancing the homing and anti-peritoneal fibrosis capabilities of bone marrow mesenchymal stromal cells (BMSCs) and to elucidate the underlying mechanisms.

METHODS

Forty male Sprague-Dawley rats were allocated into four groups: control, peritoneal dialysis fluid (PDF), PDF + BMSCs, and PDF + APSBMSCs (APS-pre-treated BMSCs). A peritoneal fibrosis model was induced using PDF. Dil-labeled BMSCs were administered intravenously. Post-transplantation, BMSC homing to the peritoneum and pathological alterations were assessed. Stromal cell-derived factor-1 (SDF-1) levels were quantified via enzyme-linked immunosorbent assay (ELISA), while CXCR4 expression in BMSCs was determined using PCR and immunofluorescence. Additionally, a co-culture system involving BMSCs and peritoneal mesothelial cells (PMCs) was established using a Transwell setup to examine the in vitro effects of APS on BMSC migration and therapeutic efficacy, with the CXCR4 inhibitor AMD3100 deployed to dissect the role of the SDF-1/CXCR4 axis and its downstream impacts.

RESULTS

In vivo and in vitro experiments confirmed that APS pre-treatment notably facilitated the targeted homing of BMSCs to the peritoneal tissue of PDF-treated rats, thereby amplifying their therapeutic impact. PDF exposure markedly increased SDF-1 levels in peritoneal and serum samples, which encouraged the migration of CXCR4-positive BMSCs. Inhibition of the SDF-1/CXCR4 axis through AMD3100 application diminished BMSC migration, consequently attenuating their therapeutic response to peritoneal mesenchyme-to-mesothelial transition (MMT). Furthermore, APS upregulated CXCR4 expression in BMSCs, intensified the activation of the SDF-1/CXCR4 axis's downstream pathways, and partially reversed the AMD3100-induced effects.

CONCLUSION

APS augments the SDF-1/CXCR4 axis's downstream pathway activation by increasing CXCR4 expression in BMSCs. This action bolsters the targeted homing of BMSCs to the peritoneal tissue and amplifies their suppressive influence on MMT, thereby improving peritoneal fibrosis.

Astragalus polysaccharide: implication for intestinal barrier, anti-inflammation, and animal production

Intestine is responsible for nutrients absorption and plays a key role in defending against various dietary allergens, antigens, toxins, and pathogens. Accumulating evidence reported a critical role of intestine in maintaining animal and human health. Since the use of antibiotics as growth promoters in animal feed has been restricted in many countries, alternatives to antibiotics have been globally investigated, and polysaccharides are considered as environmentally friendly and promising alternatives to improve intestinal health, which has become a research hotspot due to its antibiotic substitution effect. Astragalus polysaccharide (APS), a biological macromolecule, is extracted from astragalus and has been reported to exhibit complex biological activities involved in intestinal barrier integrity maintenance, intestinal microbiota regulation, short-chain fatty acids (SCFAs) production, and immune response regulation, which are critical for intestine health. The biological activity of APS is related to its chemical structure. In this review, we outlined the source and structure of APS, highlighted recent findings on the regulation of APS on physical barrier, biochemical barrier, immunological barrier, and immune response as well as the latest progress of APS as an antibiotic substitute in animal production. We hope this review could provide scientific basis and new insights for the application of APS in nutrition, clinical medicine and health by understanding particular effects of APS on intestine health, anti-inflammation, and animal production.

Astragalus polysaccharides ameliorates experimental colitis by regulating memory B cells metabolism

It is well-established that the reduced Memory B cells (MBCs) play an important role in the pathogenesis of ulcerative colitis (UC), rendering them a potential therapeutic target for UC intervention. Astragalus polysaccharide (APS), a primary active constituent derived from the classic traditional Chinese medicine Astragalus membranaceus (AM), has been used for centuries in the treatment of UC in both human and animal subjects due to its renowned immunomodulatory properties. However, it is unknown whether APS can regulate MBCs to alleviate experimental colitis. In the present investigation, the murine colitis was successfully induced using dextran sulphate sodium (DSS) and subsequently treated with APS for a duration of 7 days. APS exhibited significant efficacy in reducing the disease activity index (DAI), colonic weight index, the index of colonic weight/colonic length. Furthermore, APS mitigated colonic pathological injuries, restored the colonic length, elevated the immunoglobulin A (IgA), transforming growth factor-β1 (TGF-β1) and interleukin (IL)-10 levels, while concurrently suppressing IgG, IgM, IL-6, tumor necrosis factor alpha (TNF-α) levels. Crucially, the quantities of MBCs, IgA+MBCs and forkhead box P3 (Foxp3+) MBCs were notably increased along with a concurrent decrease in IgG1+MBCs, IG2a+MBCs, IgG2b+MBCs after APS administration in colitis mice. Additionally, the Mitotracker red expressions of MBCs and their subgroups demonstrated a significantly up-regulation. Meanwhile, the transcriptomics analysis identified mitochondrial metabolism as the predominant and pivotal mechanism underlying APS-mediated mitigation of DSS-induced colitis. Key differentially expressed genes, including B-cell linker (BLNK), aldehyde dehydrogenase 1A1 (ALDH1A1), B-cell lymphoma 6 (BCL-6), B-lymphocyte-induced maturation protein 1 (Blimp-1), paired box gene 5 (PAX5), purinergic 2 × 7 receptor (P2X7R), B Cell activation factor (BAFF), B Cell activation factor receptor (BAFFR), CD40, nuclear factor kappa-B (NF-κB), IL-6 and so on were implicated in this process. These mRNA expressions were validated through quantitative polymerase chain reaction (qPCR) and immunohistochemistry. These findings revealed that APS effectively restored MBCs and their balance to ameliorate DSS-induced colitis, which was potentially realized via promoting mitochondrial metabolism to maintain MBCs activation.

Astragalus polysaccharide attenuates diabetic nephropathy by reducing apoptosis and enhancing autophagy through activation of Sirt1/FoxO1 pathway

OBJECTIVE

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease in diabetic patients. Astragalus polysaccharide (APS) is a natural active ingredient in Astragalus membranaceus with anti-hypertensive and anti-oxidative properties. This study aimed to explore the protective roles of APS and its underlying mechanisms in DN.

METHODS

After the establishment of a rat model of DN by a high-fat diet and treatment with 30 mg/kg streptozotocin (STZ), the effects of 100 mg/kg APS on the levels of serum creatinine, blood urea nitrogen, blood glucose, and urinary albumin-to-creatinine ratio were measured. Histopathological alterations in renal tissues, renal cell apoptosis, renal inflammation, and oxidative stress were examined. The impacts of 0-200 μg/mL APS on the viability and apoptosis in high glucose (HG)-stimulated podocytes were measured by Cell Counting Kit-8 assays and flow cytometry, respectively. The expression of genes was tested by immunoblotting, quantitative real-time PCR, and immunofluorescence staining.

RESULTS

APS enhanced the expression of podocin and nephrin, increased viability, and reduced apoptosis in HG-induced podocytes. APS treatment abrogated high glucose-mediate suppression of autophagy in podocytes by activating the Sirt1/FoxO1 pathway. The Sirt1 inhibitor EX-527 eliminated the ameliorative effects of APS on renal dysfunction and renal tissue damage, as well as the inhibitory effects of APS on oxidative stress, inflammation, and apoptosis in DN rats. Moreover, EX-527 inhibited APS-induced autophagy activation in DN rats.

CONCLUSION

APS mitigated DN under hyperglycemic conditions by activating the Sirt1/FoxO1 autophagy pathway, suggesting that APS is a promising agent for DN treatment.

Astragalus polysaccharide alleviates polycystic ovary syndrome by reducing insulin resistance and oxidative stress and increasing the diversity of gut microbiota

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common reproductive endocrine disorder, which is frequently accompanied by insulin resistance, oxidative stress (OS), and dyslipidemia. Astragalus polysaccharide (APS)-as a water-soluble heteropolysaccharide-can lower blood sugar and lipid and exert anti-aging effects and thus has been proven to be beneficial to various types of metabolic diseases. However, specific mechanisms of the action of APS on PCOS are yet to be studied.

METHODS

Herein, BALB/C female mice aged 3 weeks were randomly divided into three groups (10 mice/group): oil + PBS group, DHEA + PBS group, and DHEA + APS group. Changes in the estrous cycle, ovarian tissue sections, serum levels of the hormone, blood glucose, blood lipid, and OS were studied. The intestinal microbiome was sequenced and Spearman correlation analysis was used to analyze the correlation between serum metabolic indexes and microflora.

RESULTS

The results revealed that APS treatment ameliorated insulin resistance, OS, and dyslipidemia in PCOS mice. The results of 16S rDNA sequencing indicated that there were significant differences in the composition and diversity of intestinal microorganisms between DHEA and APS treatments. Firmicutes, Lachnospiraceae, Bacilli, Lactobacillaceae, and Lachnospiraceae_NK4A13_group were abundant in the oil + PBS group. Bacteroidota and Muribaculaceae were enriched in the DHEA + PBS group, while Rikenellaceae, Odoribacter, and Marinifilaceae were enriched in the DHEA + APS group. Furthermore, Spearman correlation analysis showed that there were close interactions and correlations between intestinal bacteria and indicators of blood glucose, blood lipids, steroid hormones, and OS in PCOS mice.

CONCLUSIONS

Overall, the study showed that APS improved PCOS in mice by correcting serum metabolic disorders and increasing microbiome diversity, which may provide insight into understanding the pathogenesis and be a beneficial intervention for PCOS.

Astragalus polysaccharide protects experimental colitis through an aryl hydrocarbon receptor-dependent autophagy mechanism

BACKGROUND AND PURPOSE

Disruption of intestinal barriers plays a vital role in the pathogenesis of colitis. The aryl hydrocarbon receptor (AhR) is a recognition sensor that mediates intestinal immune homeostasis and minimizes intestinal inflammation. Astragalus polysaccharide (APS) exerts pharmacological actions in colitis; however, the mechanism has not been elucidated. We investigated whether APS protects through AhR-dependent autophagy.

EXPERIMENTAL APPROACH

The symptoms of dextran sulfate sodium (DSS)-induced colitis in mice involving intestinal barrier function and inflammatory injury were evaluated after APS administration. Intestinal-specific Becn1 conditional knockout (Becn1 cKO) mice were constructed and compared with wild-type mice. Autophagy and the effects of APS were investigated after the deactivation of AhRs. The relationship between APS-induced AhRs and autophagic Becn1 was investigated using a dual-luciferase reporter system and chromatin immunoprecipitation (ChIP)-quantitative polymerase chain reaction assay. Caco-2 cells were used to investigate inflammatory responses and AhR-dependent autophagy.

KEY RESULTS

APS improved intestinal barrier function in inflammatory injury in colitis mice. APS triggered autophagic flow; however, knockout of Becn1 in the gut increased susceptibility to colitis, leading to diminished epithelial barrier function and severe intestinal inflammation, impairing the protective effects of APS. Mechanistically, APS-triggered autophagy depends on AhR expression. Activated AhR binds to the promoter Becn1 to operate transcription of genes involved in anti-inflammation and intestinal barrier repair, while deactivation of AhR correlated with intestinal inflammation and the therapeutic function of APS.

CONCLUSIONS AND IMPLICATIONS

APS protects colitis mice by targeting autophagy, especially as the AhR stimulates the repair of damaged intestinal barrier functions.

Astragalus polysaccharide improves diabetic ulcers by promoting M2-polarization of macrophages to reduce excessive inflammation via the β-catenin/ NF-κB axis at the late phase of wound-healing

Ethnopharmacological relevance

Astragalus polysaccharide (APS), the most biologically active ingredient of Astragali Radix, is used to treat diabetes mellitus (DM)-related chronic wounds in traditional Chinese medicine for several decades. This herb possesses an anti-inflammatory effect. Our study proved that APS can reduce excessive inflammation at the late phase of wound-healing in diabetic ulcers.

Aim of the study

To clarify the molecular mechanism of APS in promoting wound-healing via reducing excessive inflammation in diabetic ulcers during the late stages of wound-healing.

Methods and materials

The rat model of the diabetic ulcers was established via intraperitoneal injection of streptozocin (60 mg/kg). We detected the regulation of APS on diabetic ulcers by measuring wound-healing rates. Bioinformatics was used to predict the target genes of APS, and autodocking was used to predict the combination of APS and target genes. Immunohistochemistry, Enzyme-linked immunosorbent assay, Western blot, immunofluorescence staining, flow cytometry, and flow cytometric sorting were investigated.

Results

The results demonstrated that APS promoted wound-healing and inhibited excessive inflammation at the late phase of wound-healing in diabetic rats. Mechanistic findings showed that APS promoted the expression of β-catenin and Rspo3 while inhibiting the expression of NF-KB and GSK-3β, which leads to the transformation of M1-type macrophages into M2-type macrophages and thus reducing excessive inflammation at the late phase of wound-healing in diabetic ulcers.

Conclusion

We found an interesting finding that APS promoted the polarization of macrophages towards M2-type through the β-catenin/NF-κB axis to reduce excessive inflammation at the late phase of wound-healing. Therefore, APS may be a promising drug for treating diabetic ulcers in clinic.

Astragalus polysaccharide attenuates nonalcoholic fatty liver disease through THDCA in high-fat diet-fed mice

ETHNOPHARMACOLOGICAL RELEVANCE

Astragalus polysaccharide (APS) extracted from Astragalus membranaceus (Fisch.) Bunge was proven to be effective in preventing high-fat diet (HFD) induced nonalcoholic fatty liver disease (NAFLD). However, the exact mechanisms were not completely elucidated.

AIM OF THE STUDY

The aim was to reveal the mechanisms of APS on preventing NAFLD from the aspects of regulating bile acids (BAs) homeostasis.

MATERIALS AND METHODS

Serum and liver BAs in HFD fed mice with or without APS intervention were quantified with an ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) system. The effect of APS on hepatic proteins involved in BAs synthesis were analyzed with Western blot. Finally, the effect of identified taurohyodeoxycholic acid (THDCA) that was significantly increased by APS on hepatic triglyceride (TG) accumulation was explored in vivo and in vitro.

RESULTS

APS regulated serum and liver BA profiles in HFD fed mice, especially increased serum THDCA. The levels of hepatic cholesterol 7a-hydroxylase (CYP7A1) and sterol 12a-hydroxylase (CYP8B1) which catalyzed the classical BAs synthesis pathway were significantly decreased by APS, while oxysterol 7a-hydroxylase (CYP7B1) which catalyzed the alternative BAs synthesis pathway was significantly increased by APS. THDCA reduced HFD-induced hepatic lipid accumulation and improved glucose homeostasis in mice, and decreased TG level in palmitic acid/oleic acid treated alpha mouse liver 12 (AML-12) cells. THDCA significantly downregulated the protein level of cluster of differentiation 36 (CD36) involved in fatty acid transport into the liver. Importantly, THDCA showed similar effect with APS in upregulating hepatic CYP7B1 and downregulating CYP7A1.

CONCLUSION

This study revealed the protective effect of APS on NAFLD was associated with the regulation on BA profiles, and proved the potential anti-NAFLD effect of THDCA, highlighting the involvement of BA metabolism in efficacy of herb-derived polysaccharides on metabolism.

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.

The attenuating effects of synbiotic containing Cetobacterium somerae and Astragalus polysaccharide against trichlorfon-induced hepatotoxicity in crucian carp (Carassius carassius)

This study aimed to investigate the hepatotoxic effects of trichlorfon on crucian carp (Carassius carassius) and the attenuating effects of a synbiotic combination of Cetobacterium somerae and Astragalus polysaccharide on hepatotoxicity. Results showed that trichlorfon did indeed induce hepatotoxicity in crucian carp and the synbiotic reversed this hepatotoxicity caused by trichlorfon. The synbiotic increased TC, TG, LDL-C, ALT and AST levels and decreased serum HDL-C levels caused by trichlorfon. H&E and Oil Red O staining demonstrated that the synbiotic ameliorated liver damage and abnormal lipid accumulation. The activity of antioxidant enzymes (T-SOD, CAT, GSH-Px) in the liver was also enhanced by the administration of the synbiotic. The supplementation of the synbiotic also increased the level of short-chain fatty acids in the intestine. In addition, the synbiotic balanced the gut microbial composition, leading to a reduction in the abundance of potentially pathogenic bacteria and an increase in the abundance of bacteria producing short-chain fatty acids. In conclusion, these findings indicate that trichlorfon can induce hepatotoxicity in crucian carp, whereas synbiotics can regulate gut microbiota, promote the growth of beneficial bacteria and increase the production of SCFAs, and alleviate trichlorfon-induced liver injury.

Astragalus polysaccharide promotes autophagy and alleviates diabetic nephropathy by targeting the lncRNA Gm41268/PRLR pathway

BACKGROUND

Astragalus polysaccharide (APS) is a major bioactive component of the Chinese herb astragalus, with well-established protective effects on the kidney. However, the effect of APS on diabetic nephropathy (DN) is unclear.

METHODS

Long non-coding RNA (lncRNA) expression profiles in kidney samples from control, db/db, and APS-treated db/db mice were evaluated using RNA high-throughput sequencing techniques. Additionally, rat renal tubular epithelial (NRK-52E) cells were cultured in high glucose (HG) media. We inhibited the expression of Gm41268 and prolactin receptor (PRLR) by transfecting NRK-52E cells with Gm41268-targeting antisense oligonucleotides and PRLR siRNA.

RESULTS

We found that APS treatment reduced 24-h urinary protein levels and fasting blood glucose and improved glucose intolerance and pathological renal damage in db/db mice. Furthermore, APS treatment enhanced autophagy and alleviated fibrosis in the db/db mice. We identified a novel lncRNA, Gm41268, which was differentially expressed in the three groups, and the cis-regulatory target gene PRLR. APS treatment induced autophagy by reducing p62 and p-mammalian target of rapamycin (mTOR) protein levels and increasing the LC3 II/I ratio. Furthermore, APS alleviated fibrosis by downregulating fibronectin (FN), transforming growth factor-β (TGF-β), and collagen IV levels. In addition, APS reversed the HG-induced overexpression of Gm41268 and PRLR. Reduction of Gm41268 decreased PRLR expression, restored autophagy, and ameliorated renal fibrosis in vitro. Inhibition of PRLR could enhance the protective effect of APS.

CONCLUSIONS

In summary, we demonstrated that the therapeutic effect of APS on DN is mediated via the Gm41268/PRLR pathway. This information contributes to the exploration of bioactive constituents in Chinese herbs as potential treatments for DN.

Astragalus polysaccharide restores insulin secretion impaired by lipopolysaccharides through the protein kinase B /mammalian target of rapamycin/glucose transporter 2 pathway

BACKGROUND

Lipopolysaccharide (LPS)-induced dysfunction of pancreatic β-cells leads to impaired insulin (INS) secretion. Astragalus polysaccharide (APS) is a bioactive heteropolysaccharide extracted from Astragalus membranaceus and is a popular Chinese herbal medicine. This study aimed to elucidate the mechanisms by which APS affects INS secretion from β-cells under LPS stress.

METHODS

Rat insulinoma (INS-1) cells were treated with LPS at a low, medium, or high concentration of APS. Glucose-stimulated insulin secretion (GSIS) was evaluated using an enzyme-linked immunosorbent assay (ELISA). Transcriptome sequencing was used to assess genome-wide gene expression. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis was used to determine the signaling pathways affected by APS. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was performed to evaluate the gene expression of glucose transporter 2 (GLUT2), glucokinase (GCK), pancreatic duodenal homeobox-1 (PDX-1), and INS. Western blot analysis was used to detect the protein expression of phosphorylated protein kinase B (p-Akt), total Akt (t-Akt), phosphorylated mammalian target of rapamycin (p-mTOR), total mTOR (t-mTOR), and GLUT2.

RESULTS

LPS decreased GLUT2, GCK, PDX-1, and INS expression and reduced GSIS. These LPS-induced decreases in gene expression and GSIS were restored by APS treatment. In addition, transcriptome sequencing in combination with KEGG enrichment analysis revealed changes in the INS signaling pathway following APS treatment. LPS decreased p-Akt and p-mTOR expression, which was restored by APS treatment. The restorative effects of APS on GSIS as well as on the expression of GLUT2, GCK, PDX-1, and INS were abolished by treatment with the Akt inhibitor MK2206 or the mTOR inhibitor rapamycin (RPM).

CONCLUSIONS

APS restored GSIS in LPS-stimulated pancreatic β-cells by activating the Akt/mTOR/GLUT2 signaling pathway.

[Astragalus polysaccharide inhibits IDO1 expression in colon tumor microenvironment to increase intratumoral CD8~+ T cell infiltration]

This study aims to investigate the regulatory effects of Astragalus polysaccharide(APS) and APS combined with 5-fluorouracil(5-FU) on indoleamine-2,3-dioxygenase(IDO1) in the colon tumor microenvironment. Sixty Balb/c mice were randomized into a blank group, a model group, an APS group, an APS + 5-FU group, an APS + low-dose 5-FU group, and a 5-FU group. A tumor model was established by subcutaneous transplantation with CT-26 mouse colon cancer cells in other groups except the blank group. After successful modeling, each group was treated with corresponding drugs for 7 days. The general condition, body weight, and tumor volume of the mice were observed and measured daily during the treatment period. The mice were sacrificed at the end of treatment, and the tumor suppression rate and spleen index of the mice were calculated. Western blot and fluorescence quantitative PCR were employed to determine the protein and mRNA levels, respectively, of IDO1 in the tumor tissue of mice. High performance liquid chromatography was employed to measure the levels of tryptophan(Trp) and kynurenine(Kyn) in the tumor tissue of mice. Hematoxylin-eosin(HE) staining was performed to observe the histological changes of the tumor tissue, and immunohistochemistry to detect the changes of CD4 and CD8 expression in the tumor tissue. Compared with that in the model group, the tumor volume of mice in each treatment group significantly reduced. The body weights of mice in APS + 5-FU group and 5-FU group significantly reduced from day 4 to day 7 of treatment. In addition, the APS + 5-FU group and 5-FU group showed significantly decreased spleen index. The protein and mRNA levels of IDO1 were significantly down-regulated in the APS, APS + 5-FU, and APS + low-dose 5-FU groups. The drug interventions significantly increased the Trp content and decreased the Kyn content. The APS + 5-FU group showed significantly reduced infiltration of CD4~+ T lymphocytes and increased infiltration of CD8~+ T lymphocytes. APS inhibited the expression of IDO1 in the colon tumor microenvironment to increase CD8~+ T lymphocyte infiltration, and the combination of APS with 5-FU demonstrated better effect.

VP4/VP56/VP35 Virus-like Particles Effectively Protect Grass Carp (Ctenopharyngodon idella) against GCRV-II Infection

Grass carp reovirus (GCRV) seriously threatens the grass carp (Ctenopharyngodon idella) industry. Prophylactic GCRV vaccines prepared by virus-like particle (VLP) assembly biotechnology can improve effectiveness and safety. The highly immunogenic candidate antigens of GCRV vaccines that have been generally considered are the outer capsid proteins VP4, VP56, and VP35. In this study, VP4, VP56, and VP35 were expressed in an Escherichia coli expression system and a Pichia pastoris expression system. The successful assembly of uniform, stable, and non-toxic VP4/VP56/VP35 VLPs was confirmed through various assays. After vaccination and GCRV infection, the survival rate in the VLPs + adjuvant Astragalus polysaccharide (APS) group was the highest (62%), 40% higher than that in control group (22%). Through the antibody levels, tissue viral load, and antioxidant immunity assays, the P. pastoris VLP vaccine effectively improved IgM levels, alleviated tissue virus load, and regulated antioxidant immune-related indicators. The treatment with P. pastoris VLPs enhanced the mRNA expression of important immune-related genes in the head kidney, as measured by qRT-PCR assay. Upon hematoxylin-eosin staining examination, relatively reduced tissue pathological damage was observed in the VLPs + APS group. The novel vaccine using P. pastoris VLPs as an effective green biological agent provides a prospective strategy for the control of fish viral diseases.

Astragalus Polysaccharide Ameliorates Renal Inflammatory Responses in a Diabetic Nephropathy by Suppressing the TLR4/NF-κB Pathway

Background

Diabetic nephropathy (DN), as a chronic inflammatory complication of diabetes, is characterized by hyperglycemia, albuminuria and edema, which ultimately becomes the leading cause of end-stage renal disease (ESRD). Astragalus polysaccharide (APS), extracted from the Astragalus membranaceus, was widely used in the treatment of diabetes mellitus. However, the functional roles of APS ameliorate inflammatory responses in DN, which remain poorly understood. Therefore, the purpose of this study was to explore the molecular mechanism of APS on DN in vivo and vitro models.

Methods

We explored the beneficial effects of APS in streptozotocin (STZ)-induced DN rat model and high glucose (HG)-treated glomerular podocyte model. The fasting blood glucose (FBG) and ratio of kidney weight to body weight were measured after 4 weeks of APS treatment. The renal injury parameters containing serum creatinine (Scr), blood urea nitrogen (BUN) and 24 h urinary protein were evaluated. The renal pathological examination was observed by hematoxylin-eosin (HE) staining. The levels of IL-1β, IL-6 and MCP-1 were evaluated by ELISA assay. The proliferation of podocytes was determined using CCK-8 assay and flow cytometry. qRT-PCR and Western blot analysis were performed to determine the amounts of TLR4/NF-κB-related gene expression.

Results

Our results indicated that APS effectively decreased the levels of FBG, BUN, Scr and renal pathological damage when compared with STZ-induced DN model group. Additionally, APS significantly ameliorated renal injury by reducing inflammatory cytokines IL-1β, IL-6, MCP-1 expression and inhibiting the TLR4/NF-κB pathway activity in DN rats. Consistent with the results in vitro, the HG-induced inflammatory response and proliferation of glomerular podocytes were also alleviated through APS administration.

Conclusion

We found that APS ameliorated DN renal injury, and the mechanisms perhaps related to relieving inflammatory responses and attenuating the TLR4/NF-κB signaling pathway.

Study on semi-bionic extraction of Astragalus polysaccharide and its anti-aging activity in vivo

Astragalus membranaceus (A. membranaceus) is a homologous plant with high medicinal and edible value. Therefore, the extraction methods of Astragalus polysaccharide (APS) have attracted the attention of many research groups, but the yield of the active components is still not high. The aim of this study was to extract APS by a semi-bionic extraction method, optimize the extraction process, and evaluate the anti-aging activities of APS in vivo. The results showed that the APS yield was 18.23% when extracted by the semi-bionic extraction method. Anti-aging evaluation in rats showed that APS extracted by this method significantly decreased the malondialdehyde (MDA) content and increased superoxide dismutase (SOD) activity to cope with D-galactose-induced aging. Serum metabolomic analysis indicated that a total of 48 potential biomarkers showed significant differences, mainly involving 5 metabolic pathways. These altered metabolic pathways were mainly related to energy metabolism, amino acid metabolism, and lipid metabolism. These results indicated that the semi-bionic extraction method can effectively improve the yield of APS, and the extracted APS exhibited anti-aging activity in rats. Our study provided a novel and effective method to extract APS and indicated that APS can be used as functional food and natural medicine to delay aging and prevent its complications.

Modulating effects of Astragalus polysaccharide on immune disorders via gut microbiota and the TLR4/NF-κB pathway in rats with syndrome of dampness stagnancy due to spleen deficiency

The syndrome of dampness stagnancy due to spleen deficiency (DSSD) is relatively common globally. Although the pathogenesis of DSSD remains unclear, evidence has suggested that the gut microbiota might play a significant role. Radix Astragali, used as both medicine and food, exerts the effects of tonifying spleen and qi. Astragalus polysaccharide (APS) comprises a macromolecule substance extracted from the dried root of Radix Astragali, which has many pharmacological functions. However, whether APS mitigates the immune disorders underlying the DSSD syndrome via regulating gut microbiota and the relevant mechanism remains unknown. Here, we used DSSD rats induced by high-fat and low-protein (HFLP) diet plus exhaustive swimming, and found that APS of moderate molecular weight increased the body weight gain and immune organ indexes, decreased the levels of interleukin-1β (IL-1β), IL-6, and endotoxin, and suppressed the Toll-like receptor 4/nuclear factor-‍κB (TLR4/NF-‍κB) pathway. Moreover, a total of 27 critical genera were significantly enriched according to the linear discriminant analysis effect size (LEfSe). APS increased the diversity of the gut microbiota and changed its composition, such as reducing the relative abundance of Pseudoflavonifractor and Paraprevotella, and increasing that of Parasutterella, Parabacteroides, Clostridium XIVb, Oscillibacter, Butyricicoccus, and Dorea. APS also elevated the contents of short-chain fatty acids (SCFAs). Furthermore, the correlation analysis indicated that 12 critical bacteria were related to the body weight gain and immune organ indexes. In general, our study demonstrated that APS ameliorated the immune disorders in DSSD rats via modulating their gut microbiota, especially for some bacteria involving immune and inflammatory response and SCFA production, as well as the TLR4/NF-κB pathway. This study provides an insight into the function of APS as a unique potential prebiotic through exerting systemic activities in treating DSSD.

Astragalus polysaccharide alleviates alcoholic-induced hepatic fibrosis by inhibiting polymerase I and transcript release factor and the TLR4/JNK/NF-κB/MyD88 pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Astragali Radix (AR), the root of Astragalus membranaceus (Fisch.) Bge. or Astragalus membranaceus (Fisch.) Bge. var. mongholicus (Bge.) Hsiao, known as Huangqi in traditional Chinese medicine, has been widely used in traditional Chinese medicine prescriptions for acute and chronic liver injury. AR was the most important medicine in a Chinese traditional prescription called Huangqi Decoction (HQD), has been used to treat chronic liver diseases since the 11th century. In particular, its major active ingredient, Astragalus polysaccharide (APS), has demonstrated promising effects on inhibiting hepatic fibrosis. However, to date, the effect of APS against alcohol-induced hepatic fibrosis and its underlying molecular mechanisms remains unknown.

AIMS OF THE STUDY

This study aimed to explore the effect and potential molecular mechanisms of APS against alcohol-induced hepatic fibrosis by using network pharmacology and experimental validation.

MATERIALS AND METHODS

The potential targets and underling mechanism of AR in alcoholic liver fibrosis was first predicted using network pharmacology, followed by experimental validation using SD rat model with alcohol-induced hepatic fibrosis. Further, the predicted candidate signaling pathways and potential target polymerase I and transcript release factor (PTRF) were combined to explore the multifaceted mechanism of APS against alcohol-induced hepatic fibrosis. Finally, overexpression of PTRF was explored to reveal the role of PTRF in the mechanism of APS against alcohol-induced hepatic fibrosis.

RESULT

APS exerted potent anti-hepatic fibrosis effects by downregulating genes involved in the Toll-like receptor 4 (TLR4)/JNK/NF-κB/MyD88 pathway. Notably, APS treatment ameliorated the hepatic damage by inhibiting the overexpression of PTRF and decreasing the co-localisation of TLR4/PTRF. Overexpression of PTRF induced reversal of the protective effects of APS on alcohol-induced hepatic fibrosis.

CONCLUSION

This study indicated that APS may alleviate alcohol-induced hepatic fibrosis by inhibiting the activation of PTRF/TLR4/JNK/NF-κB/MyD88 pathway, which provides a scientific elucidation for the mechanisms of APS on the anti-hepatic fibrosis activity and presents a promising therapeutic approach for treating hepatic fibrosis.

Astragalus polysaccharide ameliorates steroid-induced osteonecrosis of the femoral head by regulating miR-200b-3p-mediated Wnt/β-catenin signaling pathway via inhibiting SP1 expression : Astragalus polysaccharide regulates SONFH via SP1

BACKGROUND

Steroid-induced osteonecrosis of the femoral head (SONFH) is the necrosis of the femur bone caused by prolonged and massive use of corticosteroids. The present study probed into the significance of Astragalus polysaccharide (APS) in SONFH progression.

METHODS

SONFH cell model was constructed using murine long bone osteocyte Y4 (MLO-Y4) cells and then treated with APS. mRNA microarray analysis selected differentially expressed genes between control group and SONFH group. RT-qPCR determined SP1 and miR-200b-3p expression. Levels of SP1, β-catenin, autophagy-related proteins (LC3II/LC3I, Beclin1, p62) and apoptosis-related proteins (Bax, C-caspase3, C-caspase9, Bcl-2) were tested by Western blot. ChIP and luciferase reporter assays confirmed relationship between SP1 and miR-200b-3p. Fluorescence intensity of LC3 in cells was detected by immunofluorescence. Flow cytometry assessed cell apoptosis. Osteonecrosis tissues from SONFH mice were examined by HE and TRAP staining.

RESULTS

APS induced autophagy and suppressed apoptosis in SONFH cell model. APS inhibited SP1 expression and SP1 overexpression reversed effects of APS on SONFH cell model. Mechanistically, SP1 targeted miR-200b-3p to inhibit Wnt/β-catenin pathway. MiR-200b-3p depletion rescued the promoting effect of SP1 on SONFH cell model by activating Wnt/β-catenin pathway. HE staining showed that APS treatment reduced the empty lacunae and alleviated inflammation in trabecular bone of SONFH mice. TRAP staining revealed decreased osteoclasts number in SONFH mice after APS treatment.

CONCLUSION

APS regulated osteocyte autophagy and apoptosis via SP1/miR-200b-3p axis and activated Wnt/β-catenin signaling, thereby alleviating SONFH, shedding new insights for therapy of SONFH.

Astragalus polysaccharide ameliorated complex factor-induced chronic fatigue syndrome by modulating the gut microbiota and metabolites in mice

Chronic fatigue syndrome (CFS) is a debilitating disease with no symptomatic treatment. Astragalus polysaccharide (APS), a component derived from the traditional Chinese medicine A. membranaceus, has significant anti-fatigue activity. However, the mechanisms underlying the potential beneficial effects of APS on CFS remain poorly understood. A CFS model of 6-week-old C57BL/6 male mice was established using the multiple-factor method. These mice underwent examinations for behavior, oxidative stress and inflammatory indicators in brain and intestinal tissues, and ileum histomorphology. 16 S rDNA sequencing analysis indicated that APS regulated the abundance of gut microbiota and increased production of short chain fatty acids (SCFAs) and anti-inflammatory bacteria. In addition, APS reversed the abnormal expression of Nrf2, NF-κB, and their downstream factors in the brain-gut axis and alleviated the reduction in SCFAs in the cecal content caused by CFS. Further, APS modulated the changes in serum metabolic pathways induced by CFS. Finally, it was verified that butyrate exerted antioxidant and anti-inflammatory effects in neuronal cells. In conclusion, APS could increase the SCFAs content by regulating the gut microbiota, and SCFAs (especially butyrate) can further regulate the oxidative stress and inflammation in the brain, thus alleviating CFS. This study explored the efficacy and mechanism of APS for CFS from the perspective of gut-brain axis and provides a reference to further explore the efficacy of APS and the role of SCFAs in the central nervous system.

Bidirectional and persistent immunomodulation of Astragalus polysaccharide as an adjuvant of influenza and recombinant SARS-CoV-2 vaccine

Respiratory viral infections, such as coronavirus disease of 2019 (COVID-19) and influenza, cause significant morbidity and mortality and have become a worldwide public health concern with tremendous economic and societal burdens. Vaccination is a major strategy for preventing infections. However, some new vaccines have an unmet need for impairing responses in certain individuals, especially COVID-19 vaccines, despite ongoing vaccine and adjuvant research. Here, we evaluated the effectiveness of Astragalus polysaccharide (APS), a bioactive polysaccharide extracted from the traditional Chinese herb Astragalus membranaceus as an immune adjuvant to regulate the efficacy of influenza split vaccine (ISV) and recombinant severe acute respiratory syndrome (SARS)-Cov-2 vaccine in mice. Our data indicated that APS as an adjuvant can facilitate the induction of high levels of hemagglutination inhibition (HAI) titer and specific antibody immunoglobulin G (IgG) and confer protection against the lethal challenge of influenza A viruses, including increased survival and amelioration of weight loss in mice immunized with the ISV. RNA sequencing (RNA-seq) analysis revealed that the NF-κB and Fc gamma R-mediated phagocytosis signaling pathways are essential for the immune response of mice immunized with the recombinant SARS-Cov-2 vaccine (RSV). Another important finding was that bidirectional immunomodulation of APS on cellular and humoral immunity was observed, and APS-adjuvant-induced antibodies persisted at a high level for at least 20 weeks. These findings suggest that APS is a potent adjuvant for influenza and COVID-19 vaccines, and has the advantages of bidirectional immunoregulation and persistent immunity.

Regulation and mechanism of Astragalus polysaccharide on ameliorating aging in Drosophila melanogaster

Astragalus polysaccharide (APS) is a notable bioactive component of Astragalus membranaceus and has been extensively investigated for its pharmacological activities, including antioxidant, neuroprotection, and anticancer effects. However, the beneficial effects and mechanisms of APS on anti-aging diseases remain largely unknown. Here, we utilized the classic model organism Drosophila melanogaster to investigate the beneficial effects and mechanism of APS on aging-related intestinal homeostasis imbalance, sleeping disorders, and neurodegenerative diseases. The results showed that administration of APS significantly attenuated age-associated disruption of the intestinal barrier, loss of gastrointestinal acid-base balance, reduction in intestinal length, overproliferation of the intestinal stem cells (ISCs), and sleeping disorders upon aging. Furthermore, APS supplementation delayed the onset of Alzheimer's phenotypes in Aβ42-induced Alzheimer's disease (AD) flies, including the extension of lifespan and the increase in motility, but without rescuing neurobehavioral deficits in the AD model of taupathy and Parkinson's disease (PD) model of Pink1 mutation. In addition, transcriptomics was used to dissect updated mechanisms of APS on anti-aging, such as JAK-STAT signaling, Toll signaling, and IMD signaling pathways. Taken together, these studies indicate that APS plays a beneficial role in modulating aging-related diseases, thereby as a potential natural drug to delay aging.

Astragalus polysaccharide attenuates bleomycin-induced pulmonary fibrosis by inhibiting TLR4/ NF-κB signaling pathway and regulating gut microbiota

PURPOSE

Astragalus polysaccharide (APS) is a naturally-occurring compound derived from Astragalus membranaceus with anti-inflammatory and antioxidant properties. However, its beneficial effects and mechanisms on pulmonary fibrosis are unknown. Gut microbiota impact lung diseases via the gut-lung axis. Herein, we investigated APS progression to intervene in pulmonary fibrosis via the toll-like receptor 4(TLR4)/nuclear factor-kappa B(NF-κB) signaling pathway and gut microbiota homeostasis regulation.

METHODS

We used bleomycin (BLM) to construct an idiopathic pulmonary fibrosis (IPF) mouse model and assessed the pathology with Masson, hematoxylin-eosin (HE), and Sirius red staining. Enzyme-linked immunosorbent assay (ELISA) kits were employed to evaluate the inflammatory cytokine levels. Western blot evaluated TLR4/NF-κB signaling pathway expression. TUNEL staining to detect apoptosis. Mice feces samples were gathered for 16S rRNA gene sequencing.

RESULTS

Our findings revealed that APS ameliorated the extent of damage and collagen deposition in lung tissues, reduced inflammatory cytokines TNF-α, IL-6, and IL-1β levels, and decreased apoptosis. APS might attenuate the inflammatory response through TLR4/NF-κB signaling pathway inhibition. Meanwhile, the IPF mice model exhibited dysregulation of gut microbiota, and these changes were restored after APS intervention. APS may increase the proportion of probiotics, decrease that of harmful bacteria, and balance the gut microbiota via regulating metabolic pathways.

CONCLUSION

APS ameliorated lung tissue injury in the IPF mice model, inhibited TLR4/NF-κB signaling pathway, suppressed inflammatory cytokines activation, and reduced apoptosis. Moreover, APS regulated the metabolism of gut microbiota besides beneficial bacteria content elevation.

Astragalus polysaccharide promotes sheep satellite cell differentiation by regulating miR-133a through the MAPK/ERK signaling pathway

Astragalus polysaccharide (APS) possesses extensive biological activities, pharmacological effects, and anti-fatigue function. MiR-133a is a specifically expressed miRNA in skeletal muscle that participates in the regulation of myoblast proliferation and differentiation. However, little is known about the role of APS in the development of sheep skeletal muscle. In this study, we aimed to investigate the underlying mechanism of APS and miR-133a on the differentiation of sheep skeletal muscle satellite cells (SMSCs) and the regulatory relationship between APS and miR-133a. The results suggested that APS plays a positive regulatory role in the proliferation and differentiation of sheep SMSCs. Moreover, miR-133a significantly promotes SMSC differentiation and the activity of the MAPK/ERK signaling pathway. Importantly, we found that APS function requires the mediation of miR-133a in the differentiation of sheep SMSCs. Taken together, our results indicate that APS accelerates SMSC differentiation by regulating miR-133a via the MAPK/ERK signaling pathway in sheep.

Astragalus polysaccharide alleviates angiotensin II-induced glomerular podocyte dysfunction by inhibiting the expression of RARRES1 and LCN2

Podocyte loss is a predictor of kidney disease development, including diabetic nephropathy. Astragalus polysaccharide (APS) was considered a renoprotective drug, while the mechanisms operated by APS on podocyte dysfunction are rarely mentioned. This study aims at the mechanistic underlying of APS on angiotensin II (Ang II)-induced podocyte dysfunction. Mouse glomerular podocytes MPC5 were induced with Ang II, the morphologic changes were observed, and Nephrin, Desmin, and WT-1 levels were determined. The MPC5 cells were treated with APS (50, 100, and 200 μg/mL) and transduced with retinoic acid receptor responder protein 1 (RARRES1) overexpression vectors. The expression of RARRES1, lipocalin-2 (LCN2), Nephrin, and Desmin was tested, MPC5 cell viability and apoptosis were evaluated, and the levels of an endocytotic receptor megalin, Bcl-2, Bax, IL-6, IL-1β, and TNF-α were assessed. The binding of RARRES1 to LCN2 was predicted and verified. Mice were infused with Ang II to evaluate histopathological alterations and 24-h urinary albumin content. Ang II induction suppressed MPC5 cell viability, reduced the expression of Nephrin, WT-1, megalin, and Bcl-2, and augmented the expression of Desmin, Bax, IL-6, IL-1β, and TNF-α, which were significantly nullified by APS treatment. RARRES1 interacted with LCN2, and APS treatment inhibited RARRES1 and LCN2 expression in a dose-dependent manner, thereby alleviating Ang II-induced podocyte dysfunction. Ang II infusion in mice facilitated pathological alterations in renal tissues and increased urinary albumin content, which were attenuated after APS treatment. Overall, APS treatment alleviated Ang II-induced podocyte dysfunction by inhibiting RARRES1/LCN2 expression, and blocked kidney injury development in vivo. This article is protected by copyright. All rights reserved.

Effects of Astragalus polysaccharide to boar sperm on bisphenol A exposure

Bisphenol A (BPA) is reported to impair male fertility. The alleviating effect of Astragalus polysaccharide (APS) on sperm oxidative damage caused by BPA exposure was analysed for the first time. In this study, the effect of APS (0.25, 0.5, 0.75, 1 mg/mL) on motility of BPA-exposed sperm, energy metabolism indexes, and antioxidant parameters was evaluated. In addition, the effects of APS supplementation on protein tyrosine phosphorylation of BPA-exposed sperm were assessed. The results showed that the addition of APS (0.5 and 0.75 mg/mL) significantly increased motility of BPA-exposed sperm by decreasing the content of malondialdehyde and improving activities of superoxide dismutase and catalase (p < .05). Administration of different doses of APS to BPA-exposed sperm improved mitochondrial membrane potential and energy production (p < .05). Moreover, APS protected and alleviated tyrosine phosphorylation protein on the principal-pieces of BPA-exposed sperm flagella. In conclusion, supplementation with APS enhanced the antioxidant capacity of BPA-exposed sperm and improved in vitro capacitation, thereby improving the reproductive capacity of sperm exposed to environmental hormones.

Astragalus polysaccharide prevents heart failure-induced cachexia by alleviating excessive adipose expenditure in white and brown adipose tissue

BACKGROUND

Astragalus polysaccharide (APS) is a key active ingredient isolated from Astragalus membranaceus that has been reported to be a potential treatment for obesity and diabetes by regulating lipid metabolism and adipogenesis, alleviating inflammation, and improving insulin resistance. However, whether APS regulates lipid metabolism in the context of cachexia remains unclear. Therefore, this study analysed the effects of APS on lipid metabolism and adipose expenditure in a heart failure (HF)-induced cardiac cachexia rat model.  METHODS: A salt-sensitive hypertension-induced cardiac cachexia rat model was used in the present study. Cardiac function was detected by echocardiography. The histological features and fat droplets in fat tissue and liver were observed by H&E staining and Oil O Red staining. Immunohistochemical staining, Western blotting and RT‒qPCR were used to detect markers of lipolysis and adipose browning in white adipose tissue (WAT) and thermogenesis in brown adipose tissue (BAT). Additionally, sympathetic nerve activity and inflammation in adipose tissue were detected.

RESULTS

Rats with HF exhibited decreased cardiac function and reduced adipose accumulation as well as adipocyte atrophy. In contrast, administration of APS not only improved cardiac function and increased adipose weight but also prevented adipose atrophy and FFA efflux in HF-induced cachexia. Moreover, APS inhibited HF-induced lipolysis and browning of white adipocytes since the expression levels of lipid droplet enzymes, including HSL and perilipin, and beige adipocyte markers, including UCP-1, Cd137 and Zic-1, were suppressed after administration of APS. In BAT, treatment with APS inhibited PKA-p38 MAPK signalling, and these effects were accompanied by decreased thermogenesis reflected by decreased expression of UCP-1, PPAR-γ and PGC-1α and reduced FFA β-oxidation in mitochondria reflected by decreased Cd36, Fatp-1 and Cpt1. Moreover, sympathetic nerve activity and interleukin-6 levels were abnormally elevated in HF rats, and astragalus polysaccharide could inhibit their activity.

CONCLUSION

APS prevented lipolysis and adipose browning in WAT and decreased BAT thermogenesis. These effects may be related to suppressed sympathetic activity and inflammation. This study provides a potential approach to treat HF-induced cardiac cachexia.

Astragalus Polysaccharide Alleviates Constipation in the Elderly Via Modification of Gut Microbiota and Fecal Metabolism

Constipation is one of the most common gastrointestinal disorders, whose incidence increasing with age. As one of the main components, Astragalus polysaccharide (APS) has been used to treat a variety of diseases. This study aimed to explore the effects of APS on the improvement of gastrointestinal functions and learning memory in elderly rats with constipation. In this study, both 16S rRNA sequencing-based microbiome and ¹H NMR-based metabolomics were applied to demonstrate the effects of APS on host metabolism and gut microbiota of the elderly rats with constipation. On top of this, we constructed both inter- and inner-layer networks, intuitively showing the correlations among behavioral indicators, intestinal bacteria, and differential metabolites. Our results showed that APS significantly ameliorated the constipation and the cognitive dysfunctions of rats. Microbiome analysis revealed that APS raised the relative abundance of Blautia, whereas decreased the relative abundance of Lactobacillus in the elderly rats with constipation. In addition, APS decreased the levels of acetate, butyrate, and propionate in the fecal samples, correspondingly regulating glycolysis/gluconeogenesis metabolism and pyruvate metabolism. These findings lay solid foundations for understanding the pathogenesis of constipation in the elderly, and also offer a promising new treatment strategy for constipation in the elderly.

Astragalus polysaccharide (APS) attenuated PD-L1-mediated immunosuppression via the miR-133a-3p/MSN axis in HCC

CONTEXT

Astragalus polysaccharide (APS) is a new tumour therapeutic drug, that has an inhibitory effect on a variety of solid tumours. Tumour cell immunosuppression is related to the up-regulation of programmed death ligand 1 (PD-L1). However, whether APS exerts its antitumor effect by regulating PD-L1 remains unclear.

OBJECTIVE

To explore whether APS exerts its antineoplastic effect via regulating PD-L1-mediated immunosuppression in hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

SMMC-7721 cells were subcutaneous injected into BALB/C mice for HCC model establishment. Mice were intraperitoneally injected with 100, 200 and 400 mg/kg APS for 12 days. Immunohistochemistry (IHC) was performed to assess CD8⁺ T cells' rate and PD-L1 level in HCC tissues. HCC cells were pre-treated with 0.1, 0.5 and 1 mg/mL APS for 4 h, then were treated with 10 ng/mL IFN-γ 24 h. PD-L1 level and cell apoptosis was detected by flow cytometry. PD-L1 and Moesin (MSN) proteins were measured by western blot. MiR-133a-3p and MSN mRNA levels were assessed by qRT-PCR. The targets of miR-133a-3p were predicted by starBase, and which was verified by dual-luciferase reporter assay.

RESULTS

Our findings illustrated that APS dose-dependently inhibited HCC growth tested with IC₅₀ values of 4.2 mg/mL, and IFN-γ-induced PD-L1 expression and attenuated PD-L1-mediated immunosuppression in HCC cells. APS attenuated PD-L1-mediated immunosuppression via miR-133a-3p in HCC cells. Besides, miR-133a-3p targeted to MSN, and MSN inhibited the antitumor effect of APS by maintaining the stability of PD-L1. Moreover, APS attenuated PD-L1-mediated immunosuppression via the miR-133a-3p/MSN axis.

CONCLUSIONS

APS attenuated PD-L1-mediated immunosuppression via miR-133a-3p/MSN axis to develop an antitumor effect. APS may be an effective drug for HCC treatment.

[Proteomics analysis of Astragalus polysaccharide on TLR4-activated lung cancer cell-derived exosomes]

Astragalus polysaccharide(APS), one of the main active components of Astragali Radix, plays an anti-tumor effect by regulating the inflammatory microenvironment of tumors. Exosomes are small extracellular vesicles with a diameter ranging from 50 to 200 nm and carry several biological components from parental cells such as nucleic acids and proteins. When combined with recipient cells, they play an important role in intercellular communication and immune response. In this study, exosomes released from H460 cells at the inflammatory state or with APS addition activated by Toll-like receptor 4(TLR4) were extracted by ultracentrifugation and characterized by Western blot, transmission electron microscopy, and nanoparticle tracking analysis. The exosomal proteins derived from H460 cells in the three groups were further analyzed by label-free proteomics, and 897, 800, and 911 proteins were identified in the three groups(Con, LPS, and APS groups), 88% of which belonged to the ExoCarta exosome protein database. Difference statistical analysis showed that the expression of 111 proteins was changed in the LPS group and the APS group(P&lt;0.05). The biological information analysis of the differential proteins was carried out. The molecular functions, biological processes, and signaling pathways related to the differential proteins mainly involved viral processes, protein binding, and bacterial invasion of proteasome and epithelial cells. Key differential proteins mainly included plasminogen activator inhibitor-1, laminin α5, laminin α1, and CD44, indicating that tumor cells underwent systemic changes in different states and were reflected in exosomes in the inflammatory microenvironment. The analysis results also suggested that APS might affect the inflammatory microenvironment through the TLR4/MyD88/NF-κB signaling pathway or the regulation of the extracellular matrix. This study is conducive to a better understanding of the mechanism of tumor development in the inflammatory state and the exploration of the anti-inflammatory effect of APS at the exosome level.

Astragalus polysaccharide alleviated the inhibition of CSFV C-strain replication caused by PRRSV via the TLRs/NF‑κB/TNF-α pathways

It is a common phenomenon that PRRSV infection can interfere with the protective efficacy of the CSFV vaccine in clinical settings, and no effective treatment is available. In our previous study, we found that PRRSV infection could inhibit the replication of CSFV-C by promoting the high expression of inflammatory cytokines. In order to further investigate whether Chinese medicine could alleviate the inhibition effect, the PAM39 cells model, which was co-infected with PRRSV and CSFV-C, was established. The effects of Chinese medicine on this co-infection model, as well as the effect of astragalus polysaccharide on the TLRs/NF-κB/TNF-α pathways, were investigated. Our results demonstrated that PAM39 cells inoculated with different pathogenic PRRSV significantly inhibited the replication of CSFV-C and up-regulated the major inflammatory mediators, including TNF-α. For the following studies, 50 µM of astragalus polysaccharide was selected from six kinds of representative Chinese medicine based on their cytotoxicity, viral titers, and inflammatory mediators. Further experiments indicated that astragalus polysaccharide could alleviate the inhibition of CSFV-C replication in the co-infection group with no influence on cell viability. In addition, astragalus polysaccharide treatment clearly reduced P65 phosphorylation and down-regulated the expression of TLR7, TLR9, and TNF-α in co-infection group, implying that the TLRs/NF-κB/TNF-α pathways may play an important role in astragalus polysaccharide's anti-inflammatory response. In conclusion, astragalus polysaccharide treatment alleviated PRRSV-mediated inhibition of CSFV-C replication via the TLRs/NF-κB/TNF-α pathways, and the molecular mechanism of PRRSV co-infection leading to the failure of CSFV vaccine immunization was partially elucidated, providing a scientific basis for effective CSF prevention and control in pig farms.

Application of dendritic cells in tumor immunotherapy and progress in the mechanism of anti-tumor effect of Astragalus polysaccharide (APS) modulating dendritic cells: a review

Dendritic cells (DCs) are potent antigen-presenting cells (APCs) that are essential in mediating the body's natural and adaptive immune responses. The body can regulate the function of DCs in various ways to enhance their antitumor effects. In the tumour microenvironment (TME), antigen-specific T cell responses are initiated through DC processing and delivery of tumour-associated antigens (TAAs); conversely, tumour cells inhibit DC recruitment by releasing metabolites, cytokines and other regulatory TME and function. Different subpopulations of DCs exist in tumour tissues, and their functions vary. Insight into DC subgroups in TME allows assessment of the effectiveness of tumour immunotherapy. Astragalus polysaccharide (APS) is the main component of the Chinese herb Astragalus membranaceus. The study found that the antitumor effects of APS are closely related to DCs. APS can promote the expression of surface molecules CD80 and CD86, promote the maturation of DCs, and activate CTL to exert antitumor effects. We reviewed the application of DCs in tumor immunotherapy and the mechanism of modulation of DCs by Astragalus polysaccharide to provide new directions and strategies for tumor therapy and new drug development.

Effect of in ovo administration of Newcastle disease vaccine conjugated with Astragalus polysaccharide on growth performance, intestinal development, and mucosal immunity in broiler chickens

This study was conducted to investigate the effect of in ovo administration of a mixture of Astragalus polysaccharide (APS) and Newcastle disease vaccine (NDV) on growth performance, intestinal development, and mucosal immunity in newly hatched chicks. Six hundred specific-pathogen-free (SPF) Leghorn fertilised eggs were incubated in a commercial hatchery and divided into four groups: (a) control group injected with 1 ml of 0.9% physiological saline, (b) APS group injected with 1 ml of 1 mg/ml APS solution, and (c) NDV group injected with 1 ml of 10^4.0 EID₅₀ /dose of NDV solution, and (d) APS + NDV group injected with a mixture of 0.5 ml of 2 mg/ml APS plus 0.5 ml 10^4.0 EID₅₀ /dose ND vaccine (NDV) on Day 18.5 of incubation. The results showed that in ovo injection of APS or the mixture of APS and NDV increased the body weight at 1 day (IW) and final weight (FW) at 28 days and increased the feed conversion ratio (FCR) at 1-7, 8-14, 15-21, and 1-28 days of age. The villus height (VH) was increased (p < 0.05), and the crypt depth (CD) was decreased (p < 0.05) in the duodenum compared with the control group. The VH/CD ratios were increased (p < 0.05) in the APS + NDV group compared with controls, NDV group, and APS group on d3. The levels of slgA in washings were increased (p < 0.05) on Days 3, 7, 14, 21, and 28, and the number of IgA⁺ cells in the duodenum was increased on Days 7, 14, 21, and 28. In addition, the IgA⁺ cells were promoted from the villus root to the apex in the APS + NDV group. It can be concluded that in ovo administration of NDV conjugated with APS compared with NDV alone may be more effective in promoting growth performance and intestinal mucosal immunity.

Astragalus polysaccharide alleviates ulcerative colitis by regulating the balance of Tfh/Treg cells

The immunomodulatory function of natural active ingredients has long been a focus of scientific research, with recent hotspots reporting targeted modulation of the follicular helper T cells (Tfh)/regulatory T cells (Treg) balance as an emerging strategy for the treatment of ulcerative colitis (UC). Here, dextran sodium sulfate induced mice UC and Astragalus polysaccharide (APS, 200 mg/kg/day) was administered simultaneously. In this study, APS effectively alleviated colitis in mice by improving survival rate, disease activity index (DAI), the change rate of body weight, colonic length and weight, and histopathological injury of the colon. Moreover, APS regulated the expression of inflammatory cytokines interleukin (IL)-2, IL-6, IL-12p70, IL-23, Tumour necrosis factor (TNF)-ɑ, and transforming growth factor (TGF)-β1 in colonic tissues of colitis mice. Importantly, APS significantly downregulated Tfh cell and the expression of its related nuclear transcription factors Blimp-1 and Bcl-6, and cytokine IL-21. Meanwhile, APS regulated the differentiation of Tfh subpopulations in colitis mice, with Tfh10 and Tfr significantly upregulated while Tfh1, Tfh17, and Tfh21 significantly downregulated. In addition, APS significantly upregulated Treg cells and the levels of its associated nuclear transcription factor Foxp3, and cytokine IL-10 in colitis mice. In conclusion, APS effectively alleviated UC by reshaping the balance of Tfh/Treg cells.

Promotion of angiogenesis in vitro by Astragalus polysaccharide via activation of TLR4 signaling pathway

During the implantation of functional tissue-engineered constructs for treating bone defects, a functional vascular network is critical for the survival of the construct. One strategy to achieve rapid angiogenesis for this application is the co-culture of outgrowth endothelial cells (OECs) and primary human osteoblasts (POBs) within a scaffold prior to implantation. In the present study, we aim to investigate whether Astragalus polysaccharide (APS) promotes angiogenesis or vascularization via the TLR4 signaling pathway in a co-culture of OECs and POBs. The co-cultures were treated with various concentrations of APS for 24 h and, subsequently, another 7 days, followed by CD31 staining and analysis of micro-vessel-formation areas using software. Additionally, APS (0.4 mg/ml for 24 h) was added to monocultures of OECs or POBs for evaluating proliferation, apoptosis, angiogenesis, osteogenesis, TLR4 signaling pathway, and inflammatory cytokine release. We found that APS promoted angiogenesis in the co-culture at the optimal concentration of 0.4 mg/ml. TLR4 activation by APS up-regulated the expression level of TLR4/MyD88 and enhanced angiogenesis and osteogenesis in monocultures of OECs and POBs. The levels of E-selectin adhesion molecules, three cytokines (IL-6, TNF-α, and IFN-γ), and VEGF and PDGF-BB, which can induce angiogenesis, increased significantly (p < .05) following APS treatment. Therefore, APS appears to promote angiogenesis and ossification in the co-culture system via the TLR4 signaling pathway. PRACTICAL APPLICATIONS: This study demonstrates that APS may promote angiogenesis and osteocyte proliferation in OEC and POB co-culture systems through the MyD88-dependent TLR4 signaling pathway. APS might represent a potential therapeutic strategy in tissue-engineered bone implantation for the treatment of large bone defects; additionally, it has the advantage of safety, as it exhibits low or no side effects. In the future, it is expected to be used in vitro for the construction of tissue-engineered bone and in vivo after implantation in patients with bone defects for promoting rapid vascularization and ossification of tissue-engineered bone and early fusion with the recipient's bone. In addition, as a food additive, Astragalus membranaceus can be used as a tonic material in patients recovering from a fracture for promoting blood-vessel formation at the fracture site and fracture recovery. Combining traditional Chinese medicine with tissue engineering can provide further strategies for promoting the development of regenerative medicine.

Astragalus polysaccharide: a review of its immunomodulatory effect

The Astragalus polysaccharide is an important bioactive component derived from the dry root of Astragalus membranaceus. This review aims to provide a comprehensive overview of the research progress on the immunomodulatory effect of Astragalus polysaccharide and provide valuable reference information. We review the immunomodulatory effect of Astragalus polysaccharide on central and peripheral immune organs, including bone marrow, thymus, lymph nodes, spleen, and mucosal tissues. Furthermore, the immunomodulatory effect of Astragalus polysaccharide on a variety of immune cells is summarized. Studies have shown that Astragalus polysaccharide can promote the activities of macrophages, natural killer cells, dendritic cells, T lymphocytes, B lymphocytes and microglia and induce the expression of a variety of cytokines and chemokines. The immunomodulatory effect of Astragalus polysaccharide makes it promising for the treatment of many diseases, including cancer, infection, type 1 diabetes, asthma, and autoimmune disease. Among them, the anticancer effect is the most prominent. In short, Astragalus polysaccharide is a valuable immunomodulatory medicine, but further high-quality studies are warranted to corroborate its clinical efficacy.

Strontium based Astragalus polysaccharides promote osteoblasts differentiation and mineralization

Bone formation and repair represent a clinical challenge. In this work, we designed and synthesized strontium Astragalus polysaccharide (APS-Sr), a novel polysaccharide compound that should have therapeutic effects on both anti-inflammation and promoting bone formation. Using material characterization techniques, including SEM, FITR, XRD, etc., we verified the successful synthesis of this compound. Moreover, we examined the potential of this compound for promoting bone repair and inhibiting inflammatory response by cell proliferation assay, ALP and Alizarin Red staining experiments and RT-qPCR. The biological experiment results showed that APS-Sr can effectively inhibit inflammatory factors, promote osteogenic differentiation and up-regulate the bone growth factors. It is therefore believed that APS-Sr should be a promising polysaccharide compound in bone-related biomedical applications.

Astragalus Polysaccharides Reduce High-glucose-induced Rat Aortic Endothelial Cell Senescence and Inflammasome Activation by Modulating the Mitochondrial Na+/Ca2+ Exchanger

Vascular endothelial cells play a vital role in atherosclerotic changes and the progression of cardiovascular disease in older adults. Previous studies have indicated that Astragalus polysaccharides (APS), a main active component of the traditional Chinese medicine Astragalus, protect mitochondria and exert an antiaging effect in the mouse liver and brain. However, the effect of APS on rat aortic endothelial cell (RAEC) senescence and its underlying mechanism have not been investigated. In this study, we extracted RAECs from 2-month-old male Wistar rats by the tissue explant method and found that APS ameliorated the high-glucose-induced increase in the frequency of SA-β-Gal positivity and the levels of the senescence-related proteins p16, p21, and p53. APS increased the tube formation capacity of RAECs under high-glucose conditions. Moreover, APS enhanced the expression of the mitochondrial Na⁺/Ca²⁺ exchanger NCLX, and knockdown of NCLX by small interfering RNA (siRNA) transfection suppressed the antiaging effect of APS under high-glucose conditions. Additionally, APS ameliorated RAEC mitochondrial dysfunction, including increasing ATP production, cytochrome C oxidase activity and the oxygen consumption rate (OCR), and inhibited high-glucose-induced NLRP3 inflammasome activation and IL-1β release, which were reversed by siNCLX. These results indicate that APS reduces high-glucose-induced inflammasome activation and ameliorates mitochondrial dysfunction and senescence in RAECs by modulating NCLX. Additionally, APS enhanced the levels of autophagy-related proteins (LC3B-II/I, Atg7) and increased the quantity of autophagic vacuoles under high-glucose conditions. Therefore, these data demonstrate that APS may reduce vascular endothelial cell inflammation and senescence through NCLX.

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.

Astragalus polysaccharide alleviated hepatocyte senescence via autophagy pathway

Aging is characterized by inevitable organ function decline over time, with consequent body deterioration and increased susceptibility to death. Astragalus polysaccharide (APS) has been reported to have anti-oxidative, anti-apoptotic, and anti-inflammatory properties. We investigated the potential protective effects of APS on hydrogen peroxide (H₂ O₂ ) induced hepatocyte senescence and identified related mechanisms in L02, Huh7, and LM3 cell lines. Aged female C57BL/6 mice were given APS for 1 week by intraperitoneal injection, and APS provided the strongest protective effect against H₂ O₂ -induced damage at 100 μM. APS reduced the expression of cell senescence markers and alleviated pathological damage in aged mouse liver. APS treatment decreased oxidative stress, apoptosis, NOD-like receptor protein-3-mediated pyroptosis, and maintained mitochondrial homeostasis. Notably, the protective effect of APS was weakened in the presence of chloroquine. APS might enrich autophagy by activating AMP-activated protein kinase (AMPK) and inhibiting mammalian target of rapamycin (mTOR). In conclusion, APS reduced reactive oxygen species levels, inhibited apoptosis and pyroptosis, and promoted mitophagy via AMPK/mTOR pathway to alleviate hepatocyte senescence in vitro and in vivo.

Suppression of stemness and enhancement of chemosensibility in the resistant melanoma were induced by Astragalus polysaccharide through PD-L1 downregulation

Chemotherapy is commonly used in the clinical treatment of melanoma, but it is prone to resistance leading to the poor effectiveness. The mechanisms of resistance are complicated including the cancer stemness. Astragalus polysaccharide (APS) is one of the active components of traditional Chinese herbal medicine Astragalus Membranaceus. Our previous work was reported that APS had an inhibitory effect on the stemness of melanoma. In this study we established chemo-resistant melanoma cells and found that expression of stemness genes were upregulated in the resistant melanoma cells. And APS could downregulate expression of stemness genes. Furthermore, APS combined with cisplatin (DDP) could significantly slow down the tumor growth in the mouse model induced by DDP-resistant cells. In addition, we found that programmed death-ligand 1 (PD-L1) expression could be downregulated and the PI3K/AKT signaling could be affected by APS. These results suggested that APS could be a potential candidate in combination with chemotherapeutic agents, which might play a role in reducing the occurrence of resistance and improving the prognosis of melanoma patients.

Astragalus polysaccharide alleviates alveolar bone destruction by regulating local osteoclastogenesis during periodontitis

Inflammatory imbalance of bone formation/resorption leads to alveolar bone destruction. Astragalus polysaccharide has been confirmed to have anti-inflammatory effects. We sought to disclose the protective effect and its potential mechanisms of astragalus polysaccharide in the periodontitis model. Experimental periodontitis was induced by cotton ligatures for this study. We measured the alveolar bone damage rate, periodontal osteoclasts, proportion of CD4+Foxp3+, CD4+IL-10+, CD4+TGF-β+ subsets in the gingiva, and RANKL, OPG, TGF-β+, and IL-10+ level in the gingiva. We also cultured osteoclast precursor cells in the presence of RANKL and astragalus polysaccharide. Osteoclasto-like cells were identified by TRAP staining, mRNA of RANK, TRAP, and TRAF6 were evaluated by real time PCR. We found that astragalus polysaccharide caused significant protection of the alveolar bone via reducing local osteoclasts. It also decreased the proportion of CD4+Foxp3+ cells and upregulated the level of CD4+IL-10+ cells, reduced RANKL, and remedied IL-10 levels. In cell culture experiments, astragalus polysaccharide prohibited the RANKL mediated osteoclast differentiation. The findings of this study disclose the functions and possible mechanisms of astragalus polysaccharide engaged in local osteoclastogenesis, and reveal the considerable effect of astragalus polysaccharide in alveolar bone homeostasis and its likely contribution to host immuno-regulation in periodontitis.

Astragalus polysaccharide prevents ferroptosis in a murine model of experimental colitis and human Caco-2 cells via inhibiting NRF2/HO-1 pathway

Ulcerative colitis (UC) is a relapsing and remitting inflammatory bowel disease (IBD), but current conventional drugs lack efficacy. Astragalus polysaccharide (APS) is an active ingredient of Astragalus membranaceus and has been shown to ameliorate experimental colitis. In the present study, we aimed to investigate how APS affects the ferroptosis of intestinal epithelial cells in dextran sulfate sodium (DSS)-induced experimental colitis in mice. Our data showed that APS administration attenuated total weight loss, colon length shortening, disease activity index (DAI) scores, histological damage, and the expression of inflammatory cytokines in the colon of DSS-challenged mice. Moreover, we observed that treatment with APS obviously inhibited ferroptosis in both DSS-challenged mice and RSL3-stimulated Caco-2 cells, as indicated by the decrease in the expression of ferroptosis-associated genes (PTGS2, FTH, and FTL) and the levels of surrogate ferroptosis markers (MDA, GSH, and iron load). Mechanistically, the inhibitory effects of APS on ferroptosis in DSS-challenged mice and RSL3-stimulated Caco-2 cells were associated with the NRF2/HO-1 pathway. Collectively, our findings identify a new role of APS in preventing ferroptosis in a murine model of experimental colitis and human Caco-2 cells via inhibiting NRF2/HO-1 pathway.

Astragalus polysaccharide regulates brown adipocytes differentiation by miR-6911 targeting Prdm16

Brown adipose tissue (BAT) is a specialized tissue in mammals related to thermogenesis. The Astragalus polysaccharide (APS) is the major natural active component of Astragalus membranaceus, which has been recognized as one of the most popular herbal medicines worldwide. The role and possible mechanisms of APS on brown adipocytes differentiation is not well defined. Here, we explored the effect of APS on the differentiation of brown adipocytes in C3H10T 1/2 cells. The results showed that APS promoted the differentiation of brown adipocytes and improved insulin sensitivity along with significant increases in the expression of brown adipogenic marker proteins (C/EBPα, C/EBPβ, and PPARγ), thermogenesis marker proteins (UCP1, PRDM16, and PGC-1α), and insulin sensitivity marker protein (GLUT4). Meanwhile, the results showed that the amount of the phosphorylation of insulin receptor substrate 1 (p-IRS1) and phospho-AKT (p-AKT) which are critical factors in the insulin signaling pathway was increased without changing the total amount of IRS and AKT. Furthermore, the results of RNA-seq showed that APS altered the expression profiles of various miRNAs, and among which the expression of miR-6911 as a universal regulatory factor was significantly decreased. Importantly, we found that miR-6911 regulated the differentiation of brown adipocytes by targeting PR domain-containing 16 (Prdm16). In addition, after transfection of miR-6911 mimics, compared with the control and inhibitor group, PRDM16 protein expression significantly decreased, which was accompanied by the decrease of PPARγ, UCP1, and PGC-1α. Collectively, our results indicated that APS regulated brown adipocytes differentiation in C3H10T 1/2 cells via miRNA-6911 targeting Prdm16.

The anti-cancerous activity of adaptogenic herb Astragalus membranaceus

BACKGROUND

Cancer is the most dreadful disease increasing rapidly causing an economic burden globally. A standardized chemotherapy regimen planned with curative intent weakens the immune system and damages healthy cells making the patient prone to infections and severe side effects with pain and fatigue.

PURPOSE

Astragalus membranaceus (AM) has a long history of use in the treatment of severe adverse diseases. For thousands of years, it has been used in mixed herbal decoctions for the treatment of cancer. Due to growing interest in this plant root for its application to treat various types of cancers and tumors, has attracted researcher's interest.

METHOD

The literature search was done from core collections of electronic databases such as Web of Science, Google Scholar, PubMed and Science Direct using keywords given below and terms like pharmacological and phytochemical details of this plant.

OUTCOME

Astragalus membranaceus has demonstrated the ability to modulate the immune system during drug therapy making the patient physically fit and prolonged life. It has become a buzzword of herbalists as it is one of the best of seven important adaptogenic herbs with a protective effect against chronic stress and cancer. It demonstrated significant amelioration of the perilous toxic effects induced by concurrently administered chemo onco-drugs.

CONCLUSION

The natural phytoconstituents of this plant formononetin, astragalus polysaccharide, and astragalosides which show high potential anti-cancerous activity are studied and discussed in detail. One of them are used in clinical trials to overcome cancer related fatigue. Overall, this review aims to provide an insight into Astragalus membranaceus status in cancer therapy.

Effects of in ovo Injection of Astragalus Polysaccharide on the Intestinal Development and Mucosal Immunity in Broiler Chickens

The purpose of this study was to examine the effects of in ovo injection of Astragalus polysaccharide (APS) on hatchability, body weight (BW), intestinal histomorphology, the number of IgA⁺ cells and sIgA content in intestine, and the expression of intestinal immune-related genes in broiler chickens. On day 18 of the incubation, a total of 960 live embryo eggs were weighed and randomly divided into 4 treatment groups: a control group and three APS groups. The eggs in the control group were injected with 0.5 mL physiological saline. The eggs in the APS groups were injected with 3 different amounts of APS in 0.5 mL physiological saline: 1 mg (APS_L), 2 mg (APS_M) and 4 mg (APS_H). The solution was injected into the amnion of each egg. The results showed that in ovo injection of APS did not affect the hatchability but increased the body weight of the 14 d and 21 d chickens, with a significant increase observed in the APS_M group (P < 0.05). At most time points, the villus height (VH) was increased (P < 0.05) and the crypt depth (CD) was decreased (P < 0.05) in the small intestine of the broilers, with higher VH/CD ratios in the APS_L and APS_M groups compared with the control group. The number of IgA⁺ cells in the mucosa and the secretory immunoglobulin A (sIgA) levels in the intestinal washings were higher in the APS_M and APS_H groups than in the APS_L and control groups. The gene expression levels of interleukin (IL)-2, interleukin (IL)-4, interferon gamma (IFN-γ), and Toll-like receptor (TLR)-4 were significantly enhanced by APS stimulation at most time points (P < 0.05). These results indicated that in ovo injection of APS has the potential of promoting intestinal development and enhancing intestinal mucosal immunity of broiler chickens in the early stage after hatching.

Astragalus polysaccharide attenuates LPS-related inflammatory osteolysis by suppressing osteoclastogenesis by reducing the MAPK signalling pathway

Bacterial products can stimulate inflammatory reaction and activate immune cells to enhance the production of inflammatory cytokines, and finally promote osteoclasts recruitment and activity, leading to bone destruction. Unfortunately, effective preventive and treatment measures for inflammatory osteolysis are limited and usually confuse the orthopedist. Astragalus polysaccharide (APS), the main extractive of Astragali Radix, has been widely used for treating inflammatory diseases. In the current study, in vitro and in vivo experimental results demonstrated that APS notably inhibited osteoclast formation and differentiation dose-dependently. Moreover, we found that APS down-regulated RANKL-related osteoclastogenesis and levels of osteoclast marker genes, such as NFATC1, TRAP, c-FOS and cathepsin K. Further underlying mechanism investigation revealed that APS attenuated activity of MAPK signalling pathways (eg ERK, JNK and p38) and ROS production induced by RANKL. Additionally, APS was also found to suppress LPS-related inflammatory osteolysis by decreasing inflammatory factors' production in vivo. Overall, our findings demonstrate that APS effectively down-regulates inflammatory osteolysis due to osteoclast differentiation and has the potential to become an effective treatment of the disorders associated with osteoclast.

Cytotoxicity and growth-inhibiting activity of Astragalus polysaccharides against breast cancer via the regulation of EGFR and ANXA1

Astragalus polysaccharide (APS) has been frequently used as an adjuvant agent responsible for its immunoregulatory activity to enhance efficacy and reduce toxicity of chemotherapy used in the management of breast cancer. However, the other synergism mechanism of APS remains unclear. This study was performed to evaluate the potential targets and possible mechanism behind APS in vivo direct anti-tumor activity on breast cancer. Multiple biological detections were conducted to investigate the protein and mRNA expression levels of key targets. In total, 116 down-regulated and 73 up-regulated differential expressed genes (DEGs) were examined from 7 gene expression datasets. Top ten hub genes were obtained in four typical protein-protein interaction (PPI) network of DEGs involved in each specific biological process (BP, cell cycle, cell proliferation, cell apoptosis and death) that was related to inhibitory activity of APS in vitro against breast cancer cell lines. Four common DEGs (EGFR, ANXA1, KIF14 and IGF1) were further identified in the above four BP-PPI networks, among which EGFR and ANXA1 were the hub genes that were potentially linked to the progression of breast cancer. The results of biological detections indicated that the expression of EGFR in breast cancer cells was down-regulated, while the expression of ANXA1 was markedly increased in response to APS. In conclusion, the present study may provide potential molecular therapeutic targets and a new insight into the mechanism of APS against breast cancer.