Astragalus polysaccharides decreased the expression of PTP1B through relieving ER stress induced activation of ATF6 in a rat model of type 2 diabetes

Endoplasmic reticulum stress mechanisms and exercise intervention in type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) is a metabolic disease primarily characterized by insulin resistance (IR) and insufficient insulin secretion. The unfolded protein response (UPR) overactivation induced by endoplasmic reticulum stress (ERS) appears to play a key role in this process, although the exact pathogenesis of T2DM is not fully understood. Studies have demonstrated that appropriate exercise can regulate ERS in the heart, liver, pancreas, skeletal muscle, and other body tissues leading to an improvement in diabetes and its complications. However, the exact mechanism remains unclear. By analyzing the relationship between ERS, T2DM pathology, and exercise intervention, this review concludes that exercise can increase insulin sensitivity, inhibit IR, promote insulin secretion and alleviate T2DM by regulating ERS. This paper specifically reviews the signaling pathways by which ERS induces diabetes, the mechanisms of exercise regulation of ERS in diabetes, and the varying effects of different types of exercise on diabetes improvement through ERS mechanisms. Physical exercise is an effective non-pharmacological intervention for T2DM. Thus, further exploration of how exercise regulates ERS in diabetes could refine "precision exercise medicine" for diabetes and identify new drug targets.

Recent advances in medicinal and edible homologous plant polysaccharides: Preparation, structure and prevention and treatment of diabetes

Medicinal and edible homologs (MEHs) can be used in medicine and food. The National Health Commission announced that a total of 103 kinds of medicinal and edible homologous plants (MEHPs) would be available by were available in 2023. Diabetes mellitus (DM) has become the third most common chronic metabolic disease that seriously threatens human health worldwide. Polysaccharides, the main component isolated from MEHPs, have significant antidiabetic effects with few side effects. Based on a literature search, this paper summarizes the preparation methods, structural characterization, and antidiabetic functions and mechanisms of MEHPs polysaccharides (MEHPPs). Specifically, MEHPPs mainly regulate PI3K/Akt, AMPK, cAMP/PKA, Nrf2/Keap1, NF-κB, MAPK and other signaling pathways to promote insulin secretion and release, improve glycolipid metabolism, inhibit the inflammatory response, decrease oxidative stress and regulate intestinal flora. Among them, 16 kinds of MEHPPs were found to have obvious anti-diabetic effects. This article reviews the prevention and treatment of diabetes and its complications by MEHPPs and provides a basis for the development of safe and effective MEHPP-derived health products and new drugs to prevent and treat diabetes.

Advances in polysaccharides of natural source of anti-diabetes effect and mechanism

PURPOSE

Diabetes is a chronic disease in metabolic disorder, and the pathology is characterized by insulin resistance and insulin secretion disorder in blood. In current, many studies have revealed that polysaccharides extracted from natural sources with significant anti-diabetic effects. Natural polysaccharides can ameliorate diabetes through different action mechanisms. All these polysaccharides are expected to have an important role in the clinic.

METHODS

Existing polysaccharides for the treatment of diabetes are reviewed, and the mechanism of polysaccharides in the treatment of diabetes and its structural characteristics are described in detail.

RESULTS

This article introduced the natural polysaccharide through different mechanisms of action in the treatment of diabetes, including oxidative stress, apoptosis, inflammatory response and regulation of intestinal bacteria. Natural polysaccharides can treat of diabetes by regulating signaling pathways is also a research hotspot. In addition, the structural characteristics of polysaccharides were explored. There are some structure-activity relationships between natural polysaccharides and the treatment of diabetes.

Astragalus improves intestinal barrier function and immunity by acting on intestinal microbiota to treat T2DM: a research review

Diabetes is a significant chronic endocrine/metabolism disorder that can result in a number of life-threatening consequences. According to research, the gut microbiota is strongly linked to the development of diabetes, making it a viable target for diabetes treatment. The intestinal microbiota affects intestinal barrier function, organism immunity, and thus glucose metabolism and lipid metabolism. According to research, a disruption in the intestinal microbiota causes a decrease in short-chain fatty acids (SCFAs), alters the metabolism of bile acids (BAs), branched-chain amino acids (BCAAs), lipopolysaccharide (LPS), and endotoxin secretion, resulting in insulin resistance, chronic inflammation, and the progression to type 2 diabetes mellitus (T2DM). Astragali Radix is a medicinal herb of the same genus as food that has been extensively researched for treating diabetes mellitus with promising results in recent years. Polysaccharides, saponins, flavonoids, and other components are important. Among them, Astragaloside has a role in protecting the cellular integrity of the pancreas and liver, can leading to alleviation of insulin resistance and reducing blood glucose and triglyceride (TC) levels; The primary impact of Astragalus polysaccharides (APS) on diabetes is a decrease in insulin resistance, encouragement of islet cell proliferation, and suppression of islet β cell death; Astragali Radix flavonoids are known to enhance immunity, anti-inflammatory, regulate glucose metabolism and control the progression of diabetes. This study summarizes recent studies on Astragali Radix and its group formulations in the treatment of type 2 diabetes mellitus by modulating the intestinal microbiota.

Astragalus polysaccharides alleviate type 1 diabetes via modulating gut microbiota in mice

Type 1 diabetes (T1D) is a serious health problem that needs to be addressed worldwide. Astragalus polysaccharides (APS), the main chemical components of Astragali Radix, have anti-diabetic activity. As most plant polysaccharides are difficult to digest and absorb, we hypothesised that APS exert hypoglycaemic effects through the gut. This study intends to investigate the modulation of T1D associated with gut microbiota by neutral fraction of Astragalus polysaccharides (APS-1). T1D mice were induced with streptozotocin and then treated with APS-1 for 8 weeks. Fasting blood glucose levels were decreased and the insulin levels were increased in T1D mice. The results demonstrated that APS-1 improved gut barrier function by regulating ZO-1, Occludin and Claudin-1 expression, and reconstructed gut microbiota by increasing the relative abundance of Muribaculum, Lactobacillus and Faecalibaculum. In addition, APS-1 significantly increased the levels of acetic acid, propionic acid, butyric acid and inhibited the expression of pro-inflammatory factors IL-6 and TNF-α in T1D mice. Further exploration revealed that APS-1 alleviation of T1D may be associated with short-chain fatty acids (SCFAs)-producing bacteria, and that SCFAs binds to GPRs and HDACs proteins and modulate the inflammatory responses. In conclusion, the study supports the potential of APS-1 as a therapeutic agent for T1D.

Astragalus polysaccharide (APS) supplement in beagle dogs after castration: Effects on the haematology and serum chemistry profiles, immune response, and oxidative stress status

BACKGROUND

Castration is one of the most common surgical procedures performed in dogs. However, based on increasing evidence, male animals experience significant pain after castration. Astragalus polysaccharide (APS), one of the main bioactive components in A. membranaceus bunge, has been widely used as part of Fu-Zheng therapy to enhance natural defense mechanisms.

INTRODUCTION

This study was carried out to determine the effects of supplementing different doses of Astragalus polysaccharide (APS; control, 0 mg/kg; APSL, 400 mg/kg; and APSH, 800 mg/kg) for 8 weeks on the haematology and serum chemistry profiles, immune response, and oxidative stress status in weanling beagle dogs.

METHODS

After adapting to the experimental environment for 1 week, 18 male beagle dogs (Sichuan Institute of Musk Deer Breeding, China; average initial weight, 3.80 ± 0.43 g; age, 3-month-old) were randomly allotted to diets supplemented with three doses of APS (Control, 0 mg/kg; low, 400 mg/kg; and high, 800 mg/kg), referred to as control, APSL, and APSH, respectively; six dogs were assigned to each treatment. The dogs were fed the respective diets twice daily at 08:30 and 16:30 h in sufficient quantity to supply the metabolizable energy requirements for 8 weeks. On day 43 (19 weeks old), the dogs were castrated. On days 42 (prior to castration, 19 weeks old), 50 (day 7 after castration, 20 weeks old), and 57 (day 14 after castration, 21 weeks old) to measure the haematology, blood chemistry, immune response, and oxidative stress status parameters.

RESULTS

Based on our findings, the APSH diet decreased weight gain and increased the feed to gain ratio in dogs (P < 0.05). At 14 days after castration, the wound was almost closed, slightly swollen, dry, and clean in the groups supplemented with APS. In addition, optimal APS supplementation was found to decrease erythrocyte count (RBC), haematocrit (HCT), alkaline phosphatase (ALP), alanine aminotransferase (ALT), C-reactive protein (CRP), interleukin 1β (IL-1β), and tumor necrosis factor-α (TNF-α) levels, and cortisol and protein carbonyl (PC) concentrations (P < 0.05). Moreover, the mean corpuscular haemoglobin (MCH) and platelet (PLT) levels, interleukin 10 (IL-10) and glutathione (GSH) content, and Cu/Zn superoxide dismutase (SOD1), catalase (CAT), and glutathione peroxidase (Se-GPx) activities were increased in the APS supplemented groups (P < 0.05) CONCLUSION: This study demonstrated that supplementing weanling beagle dogs with optimum APS could positively affect wound healing by improving their haematological profile (decreased RBC and HCT content, increased MCH and PLT levels), serum biochemical parameters (decreased ALP and ALT content), immune status (decreased CRP, IL-1β, and TNF-α levels; increased IL-10 content), and antioxidant defense (decreased cortisol and PC content; increased GSH content, and SOD1, CAT, and Se-GPx activities). However, the detailed mechanism whereby APS regulates these changes requires further investigation. In addition, the results of this study suggest that 400 mg/kg diet is the optimum APS dose for beagle dogs.

Strong Synergic Growth Inhibition and Death Induction of Cancer Cells by Astragalus membranaceus and Vaccaria hispanica Extract

We present here a new, classification-based screening method for anti-cancer botanical combinations. Using this method, we discovered that the combination of Astragalus membranaceus and Vaccaria hispanica (AV) has strong synergic anti-proliferative and killing effects on cancer cells. We showed that AV induces the hyper activation of proliferation and survival pathways (Akt and ERK1/2) and strongly downregulates the cell cycle control proteins p21 and p27. Moreover, FACS analyses revealed that AV induces accumulation of cells in G2/M phase, supported by accumulation of cyclin A. Taken together, our results suggest that AV interferes with the cell cycle in cancer cells, leading to accumulation in G2/M and apoptosis. Further studies are needed to validate the generalizability of the anti-cancer effect of the AV combination, to fully understand its mechanism of action and to evaluate its potential as a new anti-cancer treatment.

Astragalus Polysaccharides Promote Wound Healing in Diabetic Rats by Upregulating PETN and Inhibiting the mTOR Pathway

Objective. Presently, astragalus polysaccharide (APS) is being investigated for its therapeutic potential in various diseases; however, its underlying mechanism has not yet been clarified. This study was aimed at observing the effects of APS on wound healing in diabetic rats and at exploring its underlying mechanism. Methods. Streptozotocin was injected into the tail vein of SD rats to induce diabetic animal models, in which an incision on the back was made. Rats were treated with different dosages of APS to observe their wound healing. Additionally, RT-qPCR and Western blot assay were conducted to observe the expression levels of PTEN and mTOR pathway-associated factors. Results. Diabetic rats had a prolonged wound healing process, fewer blood vessels, and increased inflammatory response, in which decreased PTEN and elevated mTOR phosphorylation were also identified. APS effectively improved wound healing in a dose-dependent manner by inhibiting the release of inflammatory mediators and attenuating endothelial injuries. Suppression of PTEN could effectively increase the phosphorylation of mTOR and diminish the therapeutic functions of APS on wound healing in diabetic rats. Conclusion. This study highlighted that APS could promote wound healing in diabetic rats by upregulating PTEN and suppressing the mTOR pathway activation.

Astragalus mongholicus powder, a traditional Chinese medicine formula ameliorate type 2 diabetes by regulating adipoinsular axis in diabetic mice

The global morbidity of obesity and type 2 diabetes mellitus (T2DM) has dramatically increased. Insulin resistance is the most important pathogenesis and therapeutic target of T2DM. The traditional Chinese medicine formula Astragalus mongholicus powder (APF), consists of Astragalus mongholicus Bunge [Fabaceae], Pueraria montana (Lour.) Merr. [Fabaceae], and Morus alba L. [Moraceae] has a long history to be used to treat diabetes in ancient China. This work aims to investigate the effects of APF on diabetic mice and its underlying mechanism. Diabetic mice were induced by High-fat-diet (HFD) and streptozotocin (STZ). The body weight of mice and their plasma levels of glucose, insulin, leptin and lipids were examined. Reverse transcription-polymerase chain reaction, histology, and Western blot analysis were performed to validate the effects of APF on diabetic mice and investigate the underlying mechanism. APF reduced hyperglycemia, hyperinsulinemia, and hyerleptinemia and attenuate the progression of obesity and non-alcoholic fatty liver disease (NAFLD). However, these effects disappeared in leptin deficient ob/ob diabetic mice and STZ-induced insulin deficient type 1 diabetic mice. Destruction of either these hormones would abolish the therapeutic effects of APF. In addition, APF inhibited the protein expression of PTP1B suppressing insulin–leptin sensitivity, the gluconeogenic gene PEPCK, and the adipogenic gene FAS. Therefore, insulin–leptin sensitivity was normalized, and the gluconeogenic and adipogenic genes were suppressed. In conclusion, APF attenuated obesity, NAFLD, and T2DM by regulating the balance of adipoinsular axis in STZ + HFD induced T2DM mice.

Identification of candidate biomarkers and pathways associated with type 1 diabetes mellitus using bioinformatics analysis

Type 1 diabetes mellitus (T1DM) is a metabolic disorder for which the underlying molecular mechanisms remain largely unclear. This investigation aimed to elucidate essential candidate genes and pathways in T1DM by integrated bioinformatics analysis. In this study, differentially expressed genes (DEGs) were analyzed using DESeq2 of R package from GSE162689 of the Gene Expression Omnibus (GEO). Gene ontology (GO) enrichment analysis, REACTOME pathway enrichment analysis, and construction and analysis of protein–protein interaction (PPI) network, modules, miRNA-hub gene regulatory network and TF-hub gene regulatory network, and validation of hub genes were performed. A total of 952 DEGs (477 up regulated and 475 down regulated genes) were identified in T1DM. GO and REACTOME enrichment result results showed that DEGs mainly enriched in multicellular organism development, detection of stimulus, diseases of signal transduction by growth factor receptors and second messengers, and olfactory signaling pathway. The top hub genes such as MYC, EGFR, LNX1, YBX1, HSP90AA1, ESR1, FN1, TK1, ANLN and SMAD9 were screened out as the critical genes among the DEGs from the PPI network, modules, miRNA-hub gene regulatory network and TF-hub gene regulatory network. Receiver operating characteristic curve (ROC) analysis confirmed that these genes were significantly associated with T1DM. In conclusion, the identified DEGs, particularly the hub genes, strengthen the understanding of the advancement and progression of T1DM, and certain genes might be used as candidate target molecules to diagnose, monitor and treat T1DM.

Pharmacological Effects and Molecular Protective Mechanisms of Astragalus Polysaccharides on Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) has been renamed metabolic dysfunction-associated fatty liver disease (MAFLD), a condition for which there is now no authorized treatment. The search for new medications to treat MAFLD made from natural substances is gaining traction. The function of anti-oxidant, anti-inflammation, hypoglycaemic, antiviral, hypolipidemic, and immunomodulatory actions of Astragalus polysaccharides (APS), a chemical molecule isolated from Astragalus membranaceus, has become the focus of therapeutic attention. We have a large number of papers on the pharmacological effects of APS on NAFLD that have never been systematically reviewed before. According to our findings, APS may help to slow the progression of non-alcoholic fatty liver disease (NAFL) to non-alcoholic steatohepatitis (NASH). Lipid metabolism, insulin resistance (IR), oxidative stress (OS), endoplasmic reticulum stress (ERS), inflammation, fibrosis, autophagy, and apoptosis are some of the pathogenic pathways involved. SIRT1/PPARα/FGF21, PI3K/AKT/IRS-1, AMPK/ACC, mTOR/4EBP-1/S6K1, GRP78/IRE-1/JNK, AMPK/PGC-1/NRF1, TLR4/MyD88/NF-κB, and TGF-β/Smad pathways were the most common molecular protective mechanisms. All of the information presented in this review suggests that APS is a natural medication with a lot of promise for NAFLD, but more study, bioavailability studies, medicine type and dosage, and clinical proof are needed. This review could be useful for basic research, pharmacological development, and therapeutic applications of APS in the management of MAFLD.

Interaction and Inhibition of a Ganoderma lucidum Proteoglycan on PTP1B Activity for Anti-diabetes

Protein tyrosine phosphatase 1B (PTP1B) is a key negative regulator of insulin and an effective target for the treatment of type 2 diabetes (T2D). A natural hyperbranched proteoglycan extracted from Ganoderma lucidum, namely, Fudan-Yueyang G. Lucidum (FYGL), was demonstrated capable of inhibiting the activity of PTP1B. Here, to identify the effective active components of FYGL, three different components, the polysaccharide FYGL-1, proteoglycans FYGL-2, and FYGL-3, were isolated from FYGL, and then, the protein moiety of FYGL-3 was further separated, namely, FYGL-3-P. Their abilities to enhance the glucose uptake in cells and inhibit the activity of PTP1B were compared. The inhibitory mechanisms were systematically explored by spectroscopic methods and MD simulations. The results showed that FYGL-3 and FYGL-3-P significantly enhanced the insulin-provoked glucose uptake in insulin-resistant HepG2 cells, detected by the glucose oxidase method. Also, the FYGL-3-P protein moiety in FYGL played an essential role in inhibiting the activity of PTP1B. A strong, enthalpy-driven, and multitargeted interaction by electrostatic forces between PTP1B and FYGL-3-P dramatically inhibited the catalytic activity of PTP1B. These results provided deep insights into the molecular mechanisms of FYGL inhibiting the activity of PTP1B and structurally helped researchers seek natural PTP1B inhibitors.

Telomerase activator-65 and pomegranate peel improved the health status of the liver in aged rats; multi-targets involved

OBJECTIVES

This study was undertaken to investigate the efficacy of telomerase activator-65 (Ta-65) and pomegranate peel against aging-induced deteriorations in the liver.

MATERIALS AND METHODS

The rats were divided into four groups: control, aged, aged rats treated with Ta-65, and pomegranate orally for two months.

RESULTS

Aging significantly increased the serum levels of total protein, globulins, and protein carbonyl and reduced the insulin-like growth factor 1 (IGF-1). It also elevated the hepatic malondialdehyde and decreased the hepatic glutathione S-transferase (GST) activity. Aging elevated the expression of thioredoxin reductase1, telomerase reverse transcriptase, and cytochrome 3a1 in the liver; it increased the p53 protein level and elevated the activity of caspase-3 in the liver indicating the occurrence of apoptosis. The architecture of the liver deteriorated in the aged rats, as shown by both light and electron microscopy examinations. The liver of the aged rats had many apoptotic hepatocytes with shrunken nuclei. Many hepatocytes had dilated rough endoplasmic reticulum, many lysosomes, and many fat droplets. Administration of Ta-65 and pomegranate to the aged rats normalized most of the previous biochemical parameters and improved the liver architecture.

CONCLUSION

Ta-65 and pomegranate have anti-aging activity through targeting multiple cellular pathways. It is also noteworthy that Ta-65 was superior to pomegranate in its alleviative effects.

Astragalus species: Insights on its chemical composition toward pharmacological applications

Astragalus L. is widely distributed throughout the temperate regions of Europe, Asia, and North America. The genus is widely used in folk medicine and in dietary supplements, as well as in cosmetics, teas, coffee, vegetable gums, and as forage for animals. The major phytoconstituents of Astragalus species with beneficial properties are saponins, flavonoids, and polysaccharides. Astragalus extracts and their isolated components exhibited promising in vitro and in vivo biological activities, including antiaging, antiinfective, cytoprotective, antiinflammatory, antioxidant, antitumor, antidiabesity, and immune-enhancing properties. Considering their proven therapeutic potential, the aim of this work is to give a comprehensive summary of the Astragalus spp. and their active components, in an attempt to provide new insight for further clinical development of these xenobiotics. This is the first review that briefly describes their ethnopharmacology, composition, biological, and toxicological properties.

HSF1 functions as a key defender against palmitic acid-induced ferroptosis in cardiomyocytes

Palmitic acid (PA)-induced myocardial injury is considered a critical contributor to the development of obesity and type 2 diabetes mellitus (T2DM)-related cardiomyopathy. However, the underlying mechanism has not been fully understood. Here, we demonstrated that PA induced the cell death of H9c2 cardiomyoblasts in a dose- and time-dependent manner, while different ferroptosis inhibitors significantly abrogated the cell death of H9c2 cardiomyoblasts and primary neonatal rat cardiomyocytes exposed to PA. Mechanistically, PA decreased the protein expression levels of both heat shock factor 1 (HSF1) and glutathione peroxidase 4 (GPX4) in a dose- and time-dependent manner, which were restored by different ferroptosis inhibitors. Overexpression of HSF1 not only alleviated PA-induced cell death and lipid peroxidation but also improved disturbed iron homeostasis by regulating the transcription of iron metabolism-related genes (e.g., Fth1, Tfrc, Slc40a1). Additionally, PA-blocked GPX4 protein expression was evidently restored by HSF1 overexpression. Inhibition of endoplasmic reticulum (ER) stress rather than autophagy contributed to HSF1-mediated GPX4 expression. Moreover, GPX4 overexpression protected against PA-induced ferroptosis, whereas knockdown of GPX4 reversed the anti-ferroptotic effect of HSF1. Consistent with the in vitro findings, PA-challenged Hsf1-/- mice exhibited more serious ferroptosis, increased Slc40a1 and Fth1 mRNA expression, decreased GPX4 and TFRC expression and enhanced ER stress in the heart compared with Hsf1+/+ mice. Altogether, HSF1 may function as a key defender against PA-induced ferroptosis in cardiomyocytes by maintaining cellular iron homeostasis and GPX4 expression.

Astragalus polysaccharide attenuates metabolic memory-triggered ER stress and apoptosis via regulation of miR-204/SIRT1 axis in retinal pigment epithelial cells

Background: ‘Metabolic memory’ of early hyperglycaemic environment has been frequently suggested in the progression of diabetic retinopathy (DR). Retinal pigment epithelial (RPE) cells are crucial targets for DR initiation following hyperglycaemia. Astragalus polysaccharides (APS) has been long used as a traditional Chinese medicine in treating diabetes. In the present study, the preventive effects and mechanisms of APS on metabolic memory-induced RPE cell death were investigated.

Methods: The expressions of miR-204 and SIRT1 were determined by reverse transcription quantitative PCR (RT-qPCR). Dual luciferase assay was applied to detect the potential targeting effects of miR-204 on SIRT1. SIRT1, ER stress and apoptosis related proteins were monitored using Western blotting. Apoptosis was assessed by TUNEL assay and Annexin V/PI staining followed by flow cytometry analysis. MiR-204 mimics and shSIRT1 were applied for miR-204 overexpression and SIRT1 knockdown, respectively.

Results: High glucose exposure induced metabolic memory, which was accompanied with sustained dysregulation of miR-204/SIRT1 axis, high level of ER stress and activation of apoptotic pathway even after replacement with normal glucose. Pre-treatment with APS concentration-dependently reversed miR-204 expression, leading to disinhibition of SIRT1 and alleviation of ER stress-induced apoptosis indicated by decreased levels of p-PERK, p-IRE-1, cleaved-ATF6, Bax, cleaved caspase-12, -9, -3, and increased levels of Bcl-2 and unleaved PARP. The effects of APS on RPE cells were reversed by either miR-204 overexpression or SIRT1 knockdown.

Conclusions: We concluded that APS inhibited ER stress and subsequent apoptosis via regulating miR-204/SIRT1 axis in metabolic memory model of RPE cells.

Network Pharmacology-Based Identification of the Mechanisms of Shen-Qi Compound Formula in Treating Diabetes Mellitus

Aim

The purpose of this research is to identify the mechanisms of Shen-Qi compound formula (SQC), a traditional Chinese medicine (TCM), for treating diabetes mellitus (DM) using system pharmacology.

Methods

The active components and therapeutic targets were identified, and these targets were analyzed using gene ontology (GO) enrichment analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, and protein-protein interaction (PPI) analysis. Finally, an integrated pathway was constructed to show the mechanisms of SQC.

Results

A total of 282 active components and 195 targets were identified through a database search. The component-target network was constructed, and the key components were screened out according to their degree. Through the GO, PPI, and KEGG analyses, the mechanism network of SQC treating DM was constructed.

Conclusions

This study shows that the mechanisms of SQC treating DM are related to various pathways and targets. This study provides a good foundation and basis for further in-depth verification and clinical application.

Metformin protects against ischaemic myocardial injury by alleviating autophagy-ROS-NLRP3-mediated inflammatory response in macrophages

Myocardial ischaemia is usually accompanied by inflammatory response which plays a critical role in the myocardial healing and scar formation, while persistent inflammatory response contributes greatly to the myocardial remodeling and consequent heart failure. Metformin (Met), a widely used hypoglycemic drug, has increasingly been shown to exert remarkable cardioprotective effect on ischaemic myocardial injury such as acute myocardial infarction (AMI). However, the underlying mechanisms are still far from being fully understood. In this study, a mouse model of AMI was established through ligating the left anterior descending coronary artery (LAD), 100 mg/kg Met was given immediately after operation once daily for 3 days. It was demonstrated that Met effectively improved the cardiac haemodynamics (LVSP, LVEDP, +dp/dt, -dp/dt), diminished the infarct size, alleviated the disarrangement of myocardial cells and reduced the infiltration of inflammatory cells (macrophages, neutrophils and lymphocytes) in the heart of AMI mice. Mechanistically, Met decreased the expression of NLRP3 and enhanced the accumulation of LC3 puncta in F4/80-positive macrophages in the heart of AMI mice. Single cell suspension of cardiac macrophages was prepared from AMI mice and exhibited increased NLRP3 mRNA and protein expression. In contrast, Met decreased the expression of NLRP3 and p62, whereas increased the ratio of LC3II/LC3I. Additionally, both conditioned medium from H9c2 cardiomyocytes exposed to hydrogen peroxide (H9c2-H₂O₂-CM) and combination of mtDNA and ATP (mtDNA-ATP) increased the expression of NLRP3 and cleaved caspase-1 (p10) as well as intracellular ROS production in RAW264.7 macrophages, which were abrogated by Met treatment. Strikingly, chloroquine (CQ), 3-methyladenine (3-MA) and knockdown of autophagy-related gene (Atg5) abrogated the inhibitory effects of Met on H9c2-H₂O₂-CM and mtDNA-ATP-induced NLRP3 expression, release of IL-1β and IL-18 as well as ROS production in RAW264.7 macrophages. Collectively, these findings suggest that Met protects against ischaemic myocardial injury through alleviating autophagy-ROS-NLRP3 axis-mediated inflammatory response in macrophages.

Astragalus Polysaccharide Promotes Adriamycin-Induced Apoptosis in Gastric Cancer Cells

Purpose

Astragalus polysaccharide (APS), a common Chinese herbal compound extracted from Astragalus membranaceus, has been proposed to increase the tumour response of and stabilize chemotherapy drugs while reducing their toxicity. Here, we examined the effects of APS on apoptosis in gastric cancer (GC) cells in the presence or absence of adriamycin (0.1 µg/mL).

Methods

GC cells cultured in the presence or absence of adriamycin (0.1 µg/mL) were administered APS (50–200 µg/mL) for 24–72 h and subjected to an MTT assay to examine cell viability. Active caspase-3 expression and DNA fragmentation were assessed to evaluate apoptosis, and real-time PCR was used to analyse the expression levels of multidrug resistance (MDR1) genes and tumour suppressor genes. Western blot analysis was applied to detect cleaved caspase-3 and phosphorylated AMPK (p-AMPK).

Results

Cellular viability was profoundly reduced by APS, and GC cell apoptosis was strongly increased by APS in a time- and dose-dependent manner; these changes may be linked to an increase in p-AMPK levels because the AMPK inhibitor compound C blocked the effects of APS. Similarly, adriamycin-induced decreases in cellular viability and apoptosis of GC cells were enhanced by APS administration. The expression of tumour suppressor genes (SEMA3F, P21^WAF1/CIP1, FBXW7), but not of MDR1, was increased by APS compared to the control, and p-AMPK levels were lower in adriamycin-resistant GC cells than in either adriamycin-sensitive GC cells or an immortalized human gastric epithelial cell line.

Conclusion

APS induces apoptosis independently and strengthens the proapoptotic effect of adriamycin on GC cells, suggesting that APS may act as a chemotherapeutic sensitizer.

A Review of the Pharmacological Action of Astragalus Polysaccharide

Astragalus membranaceus (A. membranaceus) is a type of traditional Chinese medicine with a long history of clinical application. It is used in the improvement and treatment of various diseases as medicine and food to invigorate the spleen and replenish qi. The main components of A. membranaceus are Astragalus polysaccharide (APS), flavonoids compounds, saponins compounds, alkaloids, etc. APS is the most important natural active component in A. membranaceus, and possesses multiple pharmacological properties. At present, APS possess the huge potential to develop a drug improving or treating different diseases. In this review, we reveal the potential approaches of pre-treating and preparation on APS as much as possible and the study on content of APS and its chemical composition including different monosaccharides. More importantly, this paper summarize pharmacological actions on immune regulation, such as enhancing the immune organ index, promoting the proliferation of immune cells, stimulating the release of cytokines, and affecting the secretion of immunoglobulin and conduction of immune signals; anti-aging; anti-tumor by enhancing immunity, inducing apoptosis of tumor cells and inhibiting the proliferation and transfer of tumor cells; antiviral effects; regulation of blood glucose such as type I diabetes mellitus, type II diabetes mellitus and diabetic complications; lipid-lowering; anti-fibrosis; antimicrobial activities and anti-radiation. It provided theoretical basis for the further research such as its structure and mechanism of action, and clinical application of APS.

Loss of CD36 impairs hepatic insulin signaling by enhancing the interaction of PTP1B with IR

A contradictory role of CD36 in insulin resistance was found to be related to the nutrient state. Here, we examined that the physiological functions of CD36 in insulin signal transduction in mice fed a low-fat diet. CD36 deficiency led to hepatic insulin resistance and decreased insulin-stimulated tyrosine phosphorylation of insulin receptor β (IRβ) in mice fed a low-fat diet. The ability of insulin to bind with IR did not differ between WT and CD36-deficient hepatocytes. CD36 formed a complex with IRβ and dissociation of CD36/Fyn complex or inhibition of Fyn only partially reversed the effects of CD36 on hepatic insulin signaling. Furthermore, we found that CD36 deficiency led to abnormally increased hepatic protein-tyrosine phosphatase 1B (PTP1B) expression and enhanced PTP1B and IR interactions, which contributed to the decreased insulin signaling and disordered glucose metabolism. In addition, increased endoplasmic reticulum (ER) stress was found in the livers of the CD36-deficient mice, while inhibited ER stress normalized the PTP1B expression and restored insulin signaling in the CD36-deficient mice. Our findings suggest that the loss of CD36 impairs hepatic insulin signaling by enhancing the PTP1B/IR interaction that is induced by ER stress, indicating a possible critical step in the progression of hepatic insulin resistance.

Ultra-performance liquid chromatography-mass spectrometry-based metabolomics reveals Huangqiliuyi decoction attenuates abnormal metabolism as a novel therapeutic opportunity for type 2 diabetes

Background: As a typical chronic metabolic disease, type 2 diabetes mellitus causes a heavy health-care burden to society. In this study, we applied the metabolomics strategy to explore the potential molecular mechanism of the Huangqiliuyi decoction (HQLYD) for type-2 diabetes (T2D). Ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) combined with pattern recognition methods was utilized to select specific metabolites closely associated with HQLYD. Biomarker pathway analysis and biological network were utilized to uncover the therapeutic effect and action mechanism related to HQLYD. A total of twenty-five biomarkers were identified in the animal model, in which sixteen biomarkers are associated with HQLYD treatment for T2D. They attenuated the abnormalities of metabolic pathways such as phenylalanine, tyrosine and tryptophan biosynthesis, phenylalanine metabolism, and the citrate cycle. HQLYD also significantly elevated the serum FINS and SOD, GSP-x level in the liver and kidney, and reduced the serum TC, TG, HDL, LDL, urea, Scr, AST, ALT, FBG, IRS, MDA, and CAT level. We found that the therapeutic mechanism of HQLYD against T2D affected amino acid metabolism, glucose metabolism and lipid metabolism. Metabolomics revealed that the Huangqiliuyi decoction attenuates abnormal metabolism as a novel therapeutic opportunity for type 2 diabetes.

Astragalus Polysaccharide Extends Lifespan via Mitigating Endoplasmic Reticulum Stress in the Silkworm, Bombyx mori

The traditional Chinese medicine Astragalus polysaccharide (APS) has been widely used to improve glucose homeostasis and immunoregulator properties. In recent years, it has also been shown to extend the lifespan of Caenorhabditis elegans; however, the underlying molecular mechanisms are not fully understood. Here, our study shows that APS could significantly extend adult stage, mean, and maximum lifespan of the silkworm, Bombyx mori and increase body weight without affecting food intake and fecundity. Meanwhile, the activities of glutathione S-transferase and superoxide dismutase are significantly enhanced, and the reaction oxygen species content is reduced concomitantly. Moreover, the activity of lysozyme is increased dramatically. In addition, APS rescues the shortened lifespan by Bacillus thuringiensis infection in silkworm. Furthermore, the transcription of the crucial genes involved in endoplasmic reticulum stress is upregulated upon the endoplasmic reticulum stress stimulation. APS also significantly ameliorates endoplasmic reticulum stress in silkworm cell line and in vivo. Together, the results of this study indicate that APS can prolong the silkworm lifespan by mitigating endoplasmic reticulum stress. This study improves our understanding of the molecular mechanism of APS-induced lifespan extension and highlights the importance of the silkworm as an experimental animal for evaluating the effects and revealing the mechanisms in lifespan extension of traditional Chinese medicine.

Identification and Isolation of Active Compounds from Astragalus membranaceus that Improve Insulin Secretion by Regulating Pancreatic β-Cell Metabolism

In type 2 diabetes (T2D), insufficient secretion of insulin from the pancreatic β-cells contributes to high blood glucose levels, associated with metabolic dysregulation. Interest in natural products to complement or replace existing antidiabetic medications has increased. In this study, we examined the effect of Astragalus membranaceus extract (ASME) and its compounds 1-9 on glucose-stimulated insulin secretion (GSIS) from pancreatic β-cells. ASME and compounds 1-9 isolated from A. membranaceus stimulated insulin secretion in INS-1 cells without inducing cytotoxicity. A further experiment showed that compounds 2, 3, and 5 enhanced the phosphorylation of total insulin receptor substrate-2 (IRS-2), phosphatidylinositol 3-kinase (PI3K), and Akt, and activated pancreatic and duodenal homeobox-1 (PDX-1) and peroxisome proliferator-activated receptor-γ (PPAR-γ), which are associated with β-cell function and insulin secretion. The data suggest that two isoflavonoids (2 and 3) and a nucleoside (compound 5), isolated from the roots of A. membranaceus, have the potential to improve insulin secretion in β-cells, representing the first step towards the development of potent antidiabetic drugs.

Ethnopharmacology, Phytochemistry, Pharmacology, Toxicology and Clinical Applications of Radix Astragali

Radix Astragali (RA), a traditional Chinese medicine from the dried root of Astragalus species, is widely distributed throughout the temperate regions of the world. The major bioactive constituents of RA are triterpene glycosides, flavonoids, saponins, and alkaloids, and these compounds mostly exert pharmacological activities on the cardiovascular, immune, respiratory, and hepatic systems. This review summarizes the recent studies on RA and provides a comprehensive summary regarding the status of resources, ethnopharmacology, phytochemistry, pharmacology, toxicology, clinical application, and patent release of RA. We hope this review can provide a guidance for further development of therapeutic agents from RA.

Astragalus polysaccharides inhibits cardiomyocyte apoptosis during diabetic cardiomyopathy via the endoplasmic reticulum stress pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional Chinese medicine Astragalus membranaceus (Fisch.) Bunge (AM) has been utilized for the treatment of diabetes mellitus and its complications for centuries. Astragalus polysaccharides (APS), the main bioactive ingredient extracted from the root of AM, is prescribed widely in China and has definite cardioprotective effect during diabetic cardiomyopathy (DCM). Endoplasmic reticulum (ER) stress-induced apoptosis played a crucial role in the progression of DCM. However, the regulatory mechanisms of APS on ER stress pathway haven't been comprehensively studied so far.

AIM OF THE STUDY

The aim of this study was to identify the effect of APS on cardiomyocyte apoptosis and to investigate the mechanisms for the anti-apoptotic effect of APS during DCM.

MATERIALS AND METHODS

DCM rat model was induced by intraperitoneal streptozotocin (STZ) injection and treated with APS for 16 weeks. Cardiac function, pathological changes and apoptotic cells were assessed by echocardiography, hematoxylin-eosin (HE) staining and TUNEL assay, respectively. Expressions of key molecules in ER stress pathway were detected by Western blot analysis. Cardiomyocytes were exposed to high glucose (HG) and treated with APS for 24 h. Cell viability, apoptosis and protein expressions were assessed by MTT, flow cytometer and Western blot analysis, respectively. Moreover, lentivirus over-expressing (OE) C/EBP homologous protein (CHOP) was employed to further investigate the causative role of ER stress pathway in APS-mediated effect on cardiomyocyte apoptosis.

RESULTS

In vivo, the results demonstrated that APS could improve heart function and attenuate myocardial apoptosis in DCM rat model. Further study demonstrated that APS could down-regulate the protein expressions of activating transcription factor 6 (ATF6) and protein kinase RNA-like ER kinase (PERK) related factors of ER stress pathway. In vitro, APS significantly inhibit HG stimulated H9C2 cell apoptosis and the expressions of ATF6 and PERK related proteins of ER stress pathway. However, after CHOP-OE lentivirus transfection, the protective effects of APS were diminished as increased apoptotic rate and higher expression of CHOP.

CONCLUSIONS

APS could attenuate cardiomyocyte apoptosis via down-regulating the expression of ATF6 and PERK related factors of ER stress pathway in DCM rats and HG-stimulated H9C2 cells.

A Systematic Review of Phytochemistry, Pharmacology and Pharmacokinetics on Astragali Radix: Implications for Astragali Radix as a Personalized Medicine

Astragali radix (AR) is one of the most widely used traditional Chinese herbal medicines. Modern pharmacological studies and clinical practices indicate that AR possesses various biological functions, including potent immunomodulation, antioxidant, anti-inflammation and antitumor activities. To date, more than 200 chemical constituents have been isolated and identified from AR. Among them, isoflavonoids, saponins and polysaccharides are the three main types of beneficial compounds responsible for its pharmacological activities and therapeutic efficacy. After ingestion of AR, the metabolism and biotransformation of the bioactive compounds were extensive in vivo. The isoflavonoids and saponins and their metabolites are the major type of constituents absorbed in plasma. The bioavailability barrier (BB), which is mainly composed of efflux transporters and conjugating enzymes, is expected to have a significant impact on the bioavailability of AR. This review summarizes studies on the phytochemistry, pharmacology and pharmacokinetics on AR. Additionally, the use of AR as a personalized medicine based on the BB is also discussed, which may provide beneficial information to achieve a better and more accurate therapeutic response of AR in clinical practice.

A pectic polysaccharide from water decoction of Xinjiang Lycium barbarum fruit protects against intestinal endoplasmic reticulum stress

Neutral polysaccharides from Ningxia L. barbarum fruit have been reported with immunomodulatory and antioxidative biological activities. Few studies on pectic polysaccharides have been reported, especially not from the Xinjiang L. barbarum. In the present study, a pectic polysaccharide, XLBP-I-I, was obtained from water decoction of Xinjiang L. barbarum using anion exchange chromatography and gel filtration. The results from methanolysis, methylation, FT-IR and NMR experiments indicated that XLBP-I-I was a typical pectic polysaccharide. In vitro assay showed that XLBP-I-I could reduce the ER stress and UPR in tunicamycin insult IPEC-J2 cells, and further protect IPEC-J2 cells against apoptosis induced by ER stress. These results reveal a new perspective for pectic L. barbarum polysaccharides on intestine ER stress, and this elicited interests for its further applications.

Extraction, Structure, and Pharmacological Activities of Astragalus Polysaccharides

The Astragalus polysaccharides (APS) are important bioactive components of Astragali Radix, the dry root of Astragalus membranaceus, which has been used in traditional Chinese medicine. In this review, the extraction conditions and extraction rates of APS are first compared for water, microwave-assisted, ultrasonic wave, and enzymatic hydrolysis extraction methods. Some studies have also shown that different methods can be combined to improve the extraction rate of APS. Subsequently, the chemical composition and structure of APS are discussed, as related to the extraction and purification method. Most studies have shown that APS is mainly composed of glucose, in addition to rhamnose, galactose, arabinose, xylose, mannose, glucuronic acid, and galacturonic acid. We also reviewed studies on the modification of APS using chemical methods, including sulfated modification using the chlorosulfonic acid–pyridine method, which is commonly used for chemical modification of APS. Finally, the pharmacological activities and mechanisms of action of APS are summarized, with a special focus on its immunoregulatory, antitumor, anti-inflammatory, and antiviral effects. This review will serve as a valuable resource for the research on APS.

Emerging role of Unfolded Protein Response (UPR) mediated proteotoxic apoptosis in diabetes

Endoplasmic reticulum (ER) is a crucial single membrane organelle that acts as a quality control system for cellular proteins as it is intricately involved in their synthesis, folding and trafficking to the respective targets. Type 2 diabetes is characterized by enhanced blood glucose level that promotes insulin resistance and hampers cellular glucose metabolism. Hyperglycemia provokes mitochondrial ROS production and glycation of proteins which exert a tremendous load on ER for conventional refolding of misfolded/unfolded and nascent proteins that perturb ER homeostasis resulting in apoptotic cell death. Impairment in ER functions is suspected to be through specific ER membrane-bound proteins known as Unfolded Protein Response (UPR) sensor proteins. Conformational changes in these proteins induce oligomerization and cross-autophosphorylation which facilitate processes required for the restoration of ER homeostatic imbalance. Multiple studies have reported the involvement of UPR mediated autophagy and apoptotic pathways in the progression of metabolic disorders including diabetes, cardiac ischemia/reperfusion injury and hypoxia-mediated cell death. In this review, the involvement of UPR pathways in the progression of diabetes associated complications have been addressed, which underscores molecular crosstalks during neuropathy, nephropathy, hepatic injury and retinopathy. A better understanding of these molecular interventions may reveal advanced therapeutic approaches for preventing diabetic comorbidities. The article also highlights the importance of phytochemicals that are emerging as novel ER stress inhibitors and are being explored for targeted interaction in preventing cell death responses during diabetes.

Hypothalamic endoplasmic reticulum stress as a key mediator of obesity-induced leptin resistance

Obesity is an epidemic disease that is increasing worldwide and is a major risk factor for many metabolic diseases. However, effective agents for the prevention or treatment of obesity remain limited. Therefore, it is urgent to clarify the pathophysiological mechanisms underlying the development and progression of obesity and exploit potential agents to cure and prevent this disease. According to a recent study series, obesity is associated with the development of endoplasmic reticulum stress and the activation of its stress responses (unfolded protein response) in metabolically active tissues, which contribute to the development of obesity-related insulin and leptin resistance, inflammation and energy imbalance. Hypothalamic endoplasmic reticulum stress is the central mechanism underlying the development of obesity-associated leptin resistance and disruption of energy homeostasis; thus, targeting endoplasmic reticulum stress offers a promising therapeutic strategy for improving leptin sensitivity, increasing energy expenditure and ultimately combating obesity. In this review, we highlight the relationship between and mechanism underlying hypothalamic endoplasmic reticulum stress and obesity-associated leptin resistance and energy imbalance and provide new insight regarding strategies for the treatment of obesity.

Nucleolin mediated pro-angiogenic role of Hydroxysafflor Yellow A in ischaemic cardiac dysfunction: Post-transcriptional regulation of VEGF-A and MMP-9

Hydroxysafflor Yellow A (HSYA), a most representative ingredient of Carthamus tinctorius L., had long been used in treating ischaemic cardiovascular diseases in China and exhibited prominently anticoagulant and pro-angiogenic activities, but the underlying mechanisms remained largely unknown. This study aimed to further elucidate the pro-angiogenic effect and mechanism of HSYA on ischaemic cardiac dysfunction. A C57 mouse model of acute myocardial infarction (AMI) was firstly established, and 25 mg/kg HSYA was intraperitoneally injected immediately after operation and given once, respectively, each morning and evening for 2 weeks. It was found that HSYA significantly improved ischaemia-induced cardiac haemodynamics, enhanced the survival rate, alleviated the myocardial injury and increased the expressions of CD31, vascular endothelial growth factor-A (VEGF-A) and nucleolin in the ischaemic myocardium. In addition, HSYA promoted the migration and tube formation of human umbilical vein endothelial cells (HUVECs), enhanced the expressions of nucleolin, VEGF-A and matrix metalloproteinase-9 (MMP-9) in a dose- and time-dependent manner. However, down-regulation of nucleolin expression sharply abrogated the effect mentioned above of HSYA. Further protein-RNA coimmunoprecipitation and immunoprecipitation-RT-PCR assay showed that nucleolin binded to VEGF-A and MMP-9 mRNA and overexpression of nucleolin up-regulated the mRNA expressions of VEGF-A and MMP-9 in the HUVECs through enhancing the stability of VEGF-A and MMP-9 mRNA. Furthermore, HSYA increased the mRNA expressions of VEGF-A and MMP-9 in the extract of antinucleolin antibody-precipitated protein from the heart of AMI mice. Our data revealed that nucleolin mediated the pro-angiogenic effect of HSYA through post-transcriptional regulation of VEGF-A and MMP-9 expression, which contributed to the protective effect of HSYA on ischaemic cardiac dysfunction.

Resveratrol protects against early polymicrobial sepsis-induced acute kidney injury through inhibiting endoplasmic reticulum stress-activated NF-κB pathway

Resveratrol, a polyphenol compound derived from various edible plants, protects against sepsis-induced acute kidney injury (AKI) via its anti-inflammatory activity, but the underlying mechanisms remain largely unknown. In this study, a rat model of sepsis was established by cecal ligation and puncture (CLP), 30 mg/kg resveratrol was intraperitoneally administrated immediately after the CLP operation. HK-2 cells treated by 1 μg/ml lipopolysaccharide, 0.2 μM tunicamycin, 2.5 mM irestatin 9389 and 20 μM resveratrol were used for in vitro study. The results demonstrated that resveratrol significantly improved the renal function and tubular epithelial cell injury and enhanced the survival rate of CLP-induced rat model of sepsis, which was accompanied by a substantial decrease of the serum content and renal mRNA expressions of TNF-α, IL-1β and IL-6. In addition, resveratrol obviously relieved the endoplasmic reticulum stress, inhibited the phosphorylation of inositol-requiring enzyme 1(IRE1) and nuclear factor-κB (NF-κB) in the kidney. In vitro studies showed that resveratrol enhanced the cell viability, reduced the phosphorylation of NF-κB and production of inflammatory factors in lipopolysaccharide and tunicamycin-induced HK-2 cells through inhibiting IRE1 activation. Taken together, administration of resveratrol as soon as possible after the onset of sepsis could protect against septic AKI mainly through inhibiting IRE1-NF-κB pathway-triggered inflammatory response in the kidney. Resveratrol might be a readily translatable option to improve the prognosis of sepsis.

Astragalus membranaceus-Polysaccharides Ameliorates Obesity, Hepatic Steatosis, Neuroinflammation and Cognition Impairment without Affecting Amyloid Deposition in Metabolically Stressed APPswe/PS1dE9 Mice

Astragalus membranaceus is commonly used in traditional Chinese medicine for strengthening the host defense system. Astragalus membranaceus-polysaccharides is an effective component with various important bioactivities, such as immunomodulation, antioxidant, anti-diabetes, anti-inflammation and neuroprotection. In the present study, we determine the effects of Astragalus membranaceus-polysaccharides on metabolically stressed transgenic mice in order to develop this macromolecules for treatment of sporadic Alzheimer’s disease, a neurodegenerative disease with metabolic risk factors. Transgenic mice, at 10 weeks old prior to the appearance of senile plaques, were treated in combination of administrating high-fat diet and injecting low-dose streptozotocin to create the metabolically stressed mice model. Astragalus membranaceus-polysaccharides was administrated starting at 14 weeks for 7 weeks. We found that Astragalus membranaceus-polysaccharides reduced metabolic stress-induced increase of body weight, insulin and insulin and leptin level, insulin resistance, and hepatic triglyceride. Astragalus membranaceus-polysaccharides also ameliorated metabolic stress-exacerbated oral glucose intolerance, although the fasting blood glucose was only temporally reduced. In brain, metabolic stress-elicited astrogliosis and microglia activation in the vicinity of plaques was also diminished by Astragalus membranaceus-polysaccharides administration. The plaque deposition, however, was not significantly affected by Astragalus membranaceus-polysaccharides administration. These findings suggest that Astragalus membranaceus-polysaccharides may be used to ameliorate metabolic stress-induced diabesity and the subsequent neuroinflammation, which improved the behavior performance in metabolically stressed transgenic mice.

Anti-Aging Implications of Astragalus Membranaceus (Huangqi): A Well-Known Chinese Tonic

Owing to a dramatic increase in average life expectancy and the Family Planning program of the 1970s - 1990s, China is rapidly becoming an aging society. Therefore, the investigation of healthspan-extending drugs becomes more urgent. Astragalus membranaceus (Huangqi) is a major medicinal herb that has been commonly used in many herbal formulations in the practice of traditional Chinese medicine (TCM) to treat a wide variety of diseases and body disorders, or marketed as life-prolonging extracts for human use in China, for more than 2000 years. The major components of Astragalus membranaceus are polysaccharides, flavonoids, and saponins. Pharmacological research indicates that the extract component of Astragalus membranaceus can increase telomerase activity, and has antioxidant, anti-inflammatory, immunoregulatory, anticancer, hypolipidemic, antihyperglycemic, hepatoprotective, expectorant, and diuretic effects. A proprietary extract of the dried root of Astragalus membranaceus, called TA-65, was associated with a significant age-reversal effect in the immune system. Our review focuses on the function and the underlying mechanisms of Astragalus membranaceus in lifespan extension, anti-vascular aging, anti-brain aging, and anti-cancer effects, based on experimental and clinical studies.

An NMR-Based Metabolomic Approach to Unravel the Preventive Effect of Water-Soluble Extract from Dendrobium officinale Kimura & Migo on Streptozotocin-Induced Diabetes in Mice

Dendrobium officinale Kimura & Migo (D. officinale) is a precious herbal medicine. In this study, we investigated metabolic mechanism underlying the effect of D. officinale water extract (DOWE) on diabetes prevention in mice after streptozotocin (STZ) exposure using NMR-based metabolomics. Interestingly, we found a decrease in blood glucose and an increase in liver glycogen in mice pretreated with DOWE after STZ exposure. The DOWE pretreatment significantly increased citrate and glutamine in the serum as well as creatine, alanine, leucine, isoleucine, valine, glutamine, glutathione and taurine in the liver of STZ-treated mice. Furthermore, serum glucose was significantly negatively correlated with citrate, pyruvate, alanine, isoleucine, histidine and glutamine in the serum as well as alanine and taurine in the liver. These findings suggest that the effect of DOWE on diabetes prevention may be linked to increases in liver glycogen and taurine as well as the up-regulation of energy and amino acid metabolism.

Acupuncture paired with herbal medicine for prediabetes: study protocol for a randomized controlled trial

Background

Type-2 diabetes has become a major disease and is known to seriously impair people’s health worldwide. Prediabetes includes impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) and is the most critical period for preventing type-2 diabetes, as it can be identified and reversed. Studies in the past decade have indicated that acupuncture and Chinese herbal medicine may be beneficial for treating prediabetes. However, a randomized controlled trial (RCT) should be conducted to obtain more clinical evidence on this topic.

Methods/design

An RCT will be implemented in this study, using a72-week study period (24 weeks for the intervention and 48 weeks for follow-up). Participants will be recruited from the Fifth Affiliated Hospital of Guangzhou Medical University in China. Eighty participants will be randomized to the treatment group (acupuncture plus herbal medicine and health education) or the control group (health education only), 40 participants in each. People included in this study must have been diagnosed with prediabetes using Western medicine criteria. The endpoint indices include the incidence of diabetes mellitus and the reversion rate. The primary outcome is fasting plasma glucose (FPG) level, 2-h plasma glucose (2-hPG) level after a 75-g oral glucose tolerance test (OGTT), and glycosylated hemoglobin (HbA_1c) level. Secondary outcomes include the following: Body Mass Index (BMI); hemorheology, including shear rates of whole-blood viscosity and plasma viscosity. Safety indices include hepatic (ALT, AST) and renal function (BUN, Cr) and records of adverse events, including diarrhoea, colds, pharyngitis, and sleep disorders. Quality control will be implemented, including quality control of the laboratory, researchers, participants, investigational drugs, data and documents, occurrence of bias, supervision, among others, according to uniform standard operating procedures (SOPs) which have been established by the Good Clinical Practice (GCP) office of the Fifth Affiliated Hospital of Guangzhou Medical University.

Discussion

The aim of this study is to evaluate the efficacy and safety of acupuncture paired with herbal medicine for the treatment of patients with prediabetes.

Trial registration

Chinese clinical trials register ChiCTR-INR-16008891. Registered on 23 July 2016.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-2014-4) contains supplementary material, which is available to authorized users.

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.

Screening of a natural compound library identifies emodin, a natural compound from Rheum palmatum Linn that inhibits DPP4

Historically, Chinese herbal medicines have been widely used in the treatment of hyperglycemia, but the mechanisms underlying their effectiveness remain largely unknown. Here, we screened a compound library primarily comprised of natural compounds extracted from herbs and marine organisms. The results showed that emodin, a natural compound from Rheum palmatum Linn, inhibited DPP4 activity with an in vitro IC₅₀ of 5.76 µM without inhibiting either DPP8 or DPP9. A docking model revealed that emodin binds to DPP4 protein through Glu205 and Glu206, although with low affinity. Moreover, emodin treatment (3, 10 and 30 mg/kg, P.O.) in mice decreased plasma DPP4 activity in a dose-dependent manner. Our study suggests that emodin inhibits DPP4 activity and may represent a novel therapeutic for the treatment of type 2 diabetes.

Protein Tyrosine Phosphatase 1B (PTP1B): A Potential Target for Alzheimer's Therapy?

Despite significant advances in current understanding of mechanisms of pathogenesis in Alzheimer's disease (AD), attempts at drug development based on those discoveries have failed to translate into effective, disease-modifying therapies. AD is a complex and multifactorial disease comprising a range of aberrant cellular/molecular processes taking part in different cell types and brain regions. As a consequence, therapeutics for AD should be able to block or compensate multiple abnormal pathological events. Here, we examine recent evidence that inhibition of protein tyrosine phosphatase 1B (PTP1B) may represent a promising strategy to combat a variety of AD-related detrimental processes. Besides its well described role as a negative regulator of insulin and leptin signaling, PTB1B recently emerged as a modulator of various other processes in the central nervous system (CNS) that are also implicated in AD. These include signaling pathways germane to learning and memory, regulation of synapse dynamics, endoplasmic reticulum (ER) stress and microglia-mediated neuroinflammation. We propose that PTP1B inhibition may represent an attractive and yet unexplored therapeutic approach to correct aberrant signaling pathways linked to AD.

Astragalus polysaccharides attenuate PCV2 infection by inhibiting endoplasmic reticulum stress in vivo and in vitro

This study explored the effects of Astragalus polysaccharide (APS) on porcine circovirus type 2 (PCV2) infections and its mechanism in vivo and vitro. First, fifty 2-week-old mice were randomly divided into five groups: a group without PCV2 infection and groups with PCV2 infections at 0, 100, 200 or 400 mg/kg APS treatments. The trial lasted for 28 days. The results showed that APS treatments at 200 and 400 mg/kg reduced the pathological injury of tissues, inhibited PCV2 infection and decreased glucose-regulated protein 78 (GRP78) and GADD153/CHOP gene mRNA and protein expression significantly (P < 0.05). Second, a study on endoplasmic reticulum stress mechanism was carried out in PK15 cells. APS treatments at 15 and 45 μg/mL significantly reduced PCV2 infection and GRP78 mRNA and protein expression (P < 0.05). Tunicamycin supplementation increased GRP78 mRNA and protein expression and significantly attenuated the APS-induced inhibition of PCV2 infection (P < 0.05). Tauroursodeoxycholic acid supplementation decreased GRP78 mRNA and protein expression and significantly inhibited PCV2 infection (P < 0.05). In addition, fifty 2-week-old mice were randomly divided into five groups: Con, PCV2, APS + PCV2, TM + PCV2 and TM + APS + PCV2. The results were similar to those in PK15 cells. Taken together, it could be concluded that APS suppresses PCV2 infection by inhibiting endoplasmic reticulum stress.

Antidiabetic and antihyperlipidemic activities of Forsythia suspensa (Thunb.) Vahl (fruit) in streptozotocin-induced diabetes mice

ETHNOPHARMACOLOGICAL RELEVANCE

The fruit of Forsythia suspense (Thunb.) Vahl, a well-known Chinese Materia Medica, has been traditionally used in traditional Chinese medicine for the treatment of diabetes and some other diseases, but the rational for the usage of this plant is unclear. The aim of this study was to investigate the therapeutic effect and potential mechanism of the fruit of F. suspensa using streptozotocin (STZ)-induced diabetic mice.

MATERIALS AND METHODS

Crude methanol extract of F. suspense fruit was fractionated with different solvents and the ethyl acetate fraction (EAF) was selected for in vivo studies based on the in vitro α-amylase and HMG-CoA reductase (3-hydroxy-3-methyl-glutaryl coenzyme A) inhibiting activities. For in vivo study, diabetes mellitus was induced in mice with STZ. Diabetic mice were orally administrated with 50, 100 and 200mg/kg body weight of EAF for 4 weeks. Mouse body weight, blood glucose, glucose tolerance, biochemical parameters and gene expression related to pancreas and liver function were analyzed after EAF administration.

RESULTS

After 4 weeks of EAF intervention, a significant decrease in blood glucose, triglyceride, creatinine total cholesterol, acid phosphatase, alkaline phosphatase, aspartate transaminase, alanine transaminase, and hepatic lipid (triglycerides and cholesterol) content as well as a significant increase in body weight, insulin secretion and glucose tolerance was observed in EAF treated diabetic mice. qRT-PCR analysis revealed that EAF antagonized STZ-induced alteration of the expression of rate-limiting enzymes (glucokinase and phosphorenolpyruvate carboxykinase) in liver and insulin secretion related genes insulin-1, insulin-2 and duodenal homeobox factor-1 in pancreas.

CONCLUSION

The ethyl acetate extract of Forsythia suspense (Thunb.) Vahl fruit has potency to develop an antihyperglycemic and antihyperlipidemic agent for the treatment of diabetes mellitus via modulation of oxidative stress, the hepatic glucose metabolism and pancreatic insulin secretion.

Astragalus polysaccharide modulates ER stress response in an OVA-LPS induced murine model of severe asthma

Endoplasmic reticulum (ER) stress has been recently revealed to play a pivotal role in the pathogenesis of severe asthma. Astragalus polysaccharide (APS), a major bioactive component from Astragalus membranaceus, exerts immunomodulatory and anti-inflammatory effects and has been shown to suppress ER stress in chronic diseases such as type-2 diabetes. However, the pharmaceutical application of APS in the treatment of severe asthma is unknown. The results obtained here indicate that APS significantly attenuates eosinophils and neutrophil-dominant airway inflammation by reducing the mRNA levels of Cxcl5, Il8, and chemokine (C-C motif) ligand 20 (Ccl20) and the protein levels of IL13RA and IL17RA. APS also inhibits the activation of unfolded protein response by decreasing the levels of ER stress markers such as C/EBP homologous protein (CHOP), which was associated with a reduction of PERK phosphorylation. Moreover, APS substantially blocks the nuclear translocation of ATF6 and NF-κB p65. Interestingly, we observed that APS markedly suppresses mucus hypersecretion by decreasing the levels of mucin (MUC) 5AC and MUC5B, which might be due to inhibition of goblet cells differentiation by suppressing the expression of IRE1β-correlated genes. In summary, APS can have potential pharmaceutical application in treatment of severe asthma.

The effect of Astragalus as an adjuvant treatment in type 2 diabetes mellitus: A (preliminary) meta-analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Astragalus is a traditional Chinese medicine that is widely used for tonifying Qi (Qi mainly means life energy) to treat diabetes mellitus and its complications.

AIM OF THE STUDY

We performed a meta-analysis to evaluate the effect of Astragalus in adjuvant treatment of type 2 diabetes mellitus (T2DM), and to provide novel information to improve clinical decision-making.

MATERIALS AND METHODS

We conducted an exhaustive database search (PubMed, EMbase, Cochrane Library, China Knowledge Resource Integrated Database (CNKI), Wanfang data and SinoMed) of studies associated with "Astragalus" and "type 2 diabetes mellitus" until December 2015. Following quality assessment of study eligibility, the extracted data were statistically analyzed using STATA, ver. 12.0 (Stata Corp.).

RESULTS

A total of 13 studies with 1054 participants were included in this meta-analysis. Two subgroups were identified, based on Astragalus dosing regimens: control group vs. Astragalus injection (AI); control group vs. Astragalus aqueous decoction (AAD). The pooled results showed that, in comparison with control group, Astragalus administration significantly reduced fasting plasma glucose (FPG) in both the AI group (WMD=-0.28, 95% CI=-0.46 to -0.10, P=0.002, I(2)=18.5%) and the AAD group (WMD=-0.83, 95% CI=-1.07 to -0.58, P=0.000, I(2)=0.0%); postprandial plasma glucose (PPG) was also significantly reduced in the AI group (WMD=-0.47, 95% CI=-0.77 to -0.17, P=0.002, I(2)=46.8%) and the AAD group (WMD=-1.19, 95% CI=-1.63 to -0.75, P=0.000, I(2)=49.3%). Fasting insulin (Fins) was significantly reduced only in the AAD treatment group (SMD=-0.33, 95% CI=-0.55 to -0.10, P=0.005, I(2)=1.0%) as was the homeostasis model assessment insulin resistance index (HOMA-IRI) levels (SMD=-1.66, 95% CI=-3.24 to -0.09, P=0.038, I(2)=94.0%). Although AAD treatment significantly reduced levels of glycated hemoglobin A1c (HbA1c) (WMD=-1.77, 95% CI=-3.06 to -0.47, P=0.007, I(2)=90.8%), AI treatment failed to show significant efficacy (WMD=-0.28, 95% CI=-0.63 to 0.06, P=0.102, I(2)=83.8%). Sensitivity analysis failed to detect outliers in all studies while Egger's linear regression test revealed a lack of publication bias in this meta-analysis (P=0.771, 95%CI =-3.51 to 4.56).

CONCLUSIONS

Astragalus may be beneficial as an adjuvant therapy in the treatment of type 2 diabetes. However, due to the limited quality of existing studies, further high-quality studies are warranted before definitive conclusions may be reached.

Anti-Diabetic Effect of Portulaca oleracea L. Polysaccharideandits Mechanism in Diabetic Rats

Diabetes mellitus (DM) is a metabolic syndrome caused by multiple genetic and environmental factors. Traditional Chinese medicine preparations have shown a comprehensive and function-regulating characteristic. Purslane (Portulaca oleracea L.) is an annual succulent herb. Currently, there have been some related reports on the treatment of diabetes with purslane. The current study was designed to separate and purify the polysaccharide, a systematic study of its physical and chemical properties, antioxidant activity, and anti-diabetic mechanism, in order to provide a theoretical basis for the development of drugs of purslane. A crude water soluble polysaccharide extracted from purslane was named CPOP (crude Portulaca oleracea L. polysaccharide). Effects of CPOP on bodyweight, glucose tolerance test (GTT), fasting blood glucose (FBG), fasting serum insulin (FINS), insulin sensitivity index (ISI), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), methane dicarboxylic aldehyde (MDA), and superoxygen dehydrogenises (SOD) were investigated. The results indicate that the oral administration of CPOP could significantly increase the body weight and significantly improve the glucose tolerance in diabetic rats. Meanwhile, CPOP could significantly reduce the FBG level, and elevate the FINS level and ISI value in diabetic rats. In addition, CPOP could significantly reduce TNF-α and IL-6 levels in diabetic rats; CPOP could also reduce MDA and SOD activities in the liver tissue of diabetic rats. These results suggest that the anti-diabetic effect of CPOP may be associated with its antioxidant and anti-inflammatory effects.