Astragaloside IV protects against ischemia reperfusion in a murine model of orthotopic liver transplantation

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.

The Protective Effect of Traditional Chinese Medicine on Liver Ischemia-Reperfusion Injury

Liver ischemia-reperfusion (I/R) injury occurs during transplantation and major hepatic surgery, which may lead to postoperative liver dysfunction. More and more traditional Chinese medicines (TCMs) have been used to treat liver ischemia-reperfusion injury. The purpose of this review is to evaluate the different protective effects of TCMs in the treatment of liver ischemia-reperfusion injury and to summarize its possible mechanisms. The results indicate that TCMs attenuate liver I/R injury via multiple mechanisms, including antioxidation stress, anti-inflammatory response, antiapoptosis, and inhibiting endoplasmic reticulum stress. However, the in-depth mechanism of the protective effects of these traditional Chinese medicines still remains unknown.

Inhibition or Reversal of the Epithelial-Mesenchymal Transition in Gastric Cancer: Pharmacological Approaches

Epithelial-mesenchymal transition (EMT) constitutes one of the hallmarks of carcinogenesis consisting in the re-differentiation of the epithelial cells into mesenchymal ones changing the cellular phenotype into a malignant one. EMT has been shown to play a role in the malignant transformation and while occurring in the tumor microenvironment, it significantly affects the aggressiveness of gastric cancer, among others. Importantly, after EMT occurs, gastric cancer patients are more susceptible to the induction of resistance to various therapeutic agents, worsening the clinical outcome of patients. Therefore, there is an urgent need to search for the newest pharmacological agents targeting EMT to prevent further progression of gastric carcinogenesis and potential metastases. Therapies targeted at EMT might be combined with other currently available treatment modalities, which seems to be an effective strategy to treat gastric cancer patients. In this review, we have summarized recent advances in gastric cancer treatment in terms of targeting EMT specifically, such as the administration of polyphenols, resveratrol, tangeretin, luteolin, genistein, proton pump inhibitors, terpenes, other plant extracts, or inorganic compounds.

Astragaloside and/or Hydroxysafflor Yellow A Attenuates Oxygen-Glucose Deprivation-Induced Cultured Brain Microvessel Endothelial Cell Death through Downregulation of PHLPP-1

The incidence of ischemic stroke, a life-threatening condition in humans, amongst Asians is high and the prognosis is poor. In the absence of effective therapeutics, traditional Chinese medicines have been used that have shown promising results. It is crucial to identify traditional Chinese medicine formulas that protect the blood-brain barrier, which is damaged by an ischemic stroke. In this study, we aimed to elucidate such formulas. Brain microvascular endothelial cells (BMECs) were used to establish an in vitro ischemia-reperfusion model for oxygen-glucose deprivation (OGD) experiments to evaluate the function of two traditional Chinese medicines, namely, astragaloside (AS-IV) and hydroxysafflor yellow A (HSYA), in protecting against BMEC. Our results revealed that AS-IV and HSYA attenuated the cell loss caused by OGD by increasing cell proliferation and inhibiting cell apoptosis. In addition, these compounds promoted the migration and invasion of BMECs in vitro. Furthermore, we found that BMECs rescued by AS-IV and HSYA could be functionally activated in vitro, with AS-IV and HSYA showing synergetic effects in rescuing BMECs survival in vitro by reducing the expression of PHLPP-1 and activating Akt signaling. Our results elucidated the potential of AS-IV and HSYA in the prevention and treatment of stroke by protecting against cerebral ischemia-reperfusion injury.

Analysis of astragalosides I, II and IV in some Egyptian Astragalus species and Astragalus dietary supplements using high-performance liquid chromatography/evaporative light scattering detector and non-parametric regression

INTRODUCTION

GenuTs Astragalus L. is characterised by the presence of cycloartane saponins which have wide biological activities such as antioxidant, immunomodulating' hepatoprotective and anti-inflammatory activities. From these cycloartane saponins are astragalosides I, II and IV which have been regarded as the most important active constituents in Astragalus species.

OBJECTIVES

This work describes the quantitative analysis of astragalosides I, II and IV in some Egyptian Astragalus species and Astragalus dietary supplements in a single run by high-performance liquid chromatography/evaporative light scattering detector (HPLC/ELSD) using gradient elution.

METHODOLOGY

The method of quantitation adopted in this study is the standard addition method. First and second derivative treatment of the data was performed, and the study presents comparison between two statistical regression methods for handling data; parametric and non-parametric regression methods.

RESULTS

Derivative treatment of the chromatographic response data gives improved quantitation of the chromatographic signals. Non-parametric regression of the data using Theil's method is advantageous over the usual least squares method as it assumes that errors could occur in both x- and y-directions and they might not be normally distributed. In addition, it could effectively circumvent any outlier data points.

CONCLUSION

Due to the simplicity and the good accuracy and reproducibility of the suggested methods, they could be used for analysis and quality control of Astragalus species and Astragalus dietary supplements.

Astragaloside IV derived from Astragalus membranaceus: A research review on the pharmacological effects

Decoctions prepared from the roots of Astragali Radix are known as "Huangqi" and are widely used in traditional Chinese medicine for treatment of viral and bacterial infections, inflammation, as well as cancer. Astragaloside IV (AS-IV), one of the major compounds from the aqueous extract of Astragalus membranaceus, is a cycloartane-type triterpene glycoside chemical. To date, many studies in cellular and animal models have demonstrated that AS-IV possesses potent protective effects in cardiovascular, lung, kidney and brain. Based on studies over the past several decades, this review systematically summarizes the pharmacological effects, pharmacokinetics and the toxicity of AS-IV. We analyze in detail the pharmacological effects of AS-IV on neuroprotection, liver protection, anti-cancer and anti-diabetes, attributable to its antioxidant, anti-inflammatory, anti-apoptotic properties, and the roles in enhancement of immunity, attenuation of the migration and invasion of cancer cells and improvement of chemosensitivity of chemotherapy drugs. In addition, the latest developments in the combination of AS-IV and other active ingredients of traditional Chinese medicine or chemical drugs are detailed. These pharmacological effects are associated with multiple signaling pathways, including the Raf-MEK-ERK pathway, EGFR-Nrf2 signaling pathway, Akt/PDE3B signaling pathway, AMPK signaling pathway, NF-κB signaling pathway, Nrf2 antioxidant signaling pathways, PI3K/Akt/mTOR signaling pathway, PKC-α-ERK1/2-NF-κB pathway, IL-11/STAT3 signaling pathway, Akt/GSK-3β/β-catenin pathway, JNK/c-Jun/AP-1 signaling pathway, PI3K/Akt/NF-κB pathway, miRNA-34a/LDHA pathway, Nox4/Smad2 pathway, JNK pathway and NF-kB/PPARγ pathway. This review will provide an overall understanding of the pharmacological functions of astragaloside IV on neuroprotection, liver protection, anti-cancer and anti-diabetes. In light of this, AS-IV will be a potent alternative therapeutic agent for treatment of the above mentioned diseases.

Astragaloside IV combating liver cirrhosis through the PI3K/Akt/mTOR signaling pathway

Astragaloside IV (AS-IV) in improving liver cirrhosis injury in rats and its effect on the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)/mechanistic target of rapamycin (mTOR) signaling pathway were observed. Rat model of liver cirrhosis was induced by injection of carbon tetrachloride (CCl₄). A total of 36 Sprague-Dawley (SD) rats were randomly divided into three groups: the normal control group (n=10), the model control group (n=13), and the AS-IV group (n=13). The normal control group was injected with olive oil and given carboxymethyl cellulose (CMC)-Na (10 ml/kg/day), the model control group was given CMC-Na (10 ml/kg/day), and the AS-IV group underwent intragastric administration of AS-IV (20 ml/kg/day). The content of alanine transaminase (ALT) and aspartate transaminase (AST) of rats was detected. The levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-6 and IL-1β in serum were detected via enzyme-linked immunosorbent assay (ELISA). Hematoxylin and eosin (H&E) staining was applied to observe morphological changes in liver tissues. The expression of collagens in liver tissues was detected via Masson's trichrome staining. Additionally, the expression of proteins in liver tissues was detected via western blotting. Compared with those in the blank group, the levels of AST, ALT, TNF-α, IL-6 and IL-1β were higher, the expression level of collagens in liver tissues was increased, and the expression ratios of phosphorylated (p)-PI3K/PI3K, p-Akt/Akt and p-mTOR/mTOR proteins were increased in the model group. Compared with the model group, AS-IV could significantly decrease the content of AST, ALT, TNF-α, IL-6 and IL-β in serum of rats, obviously inhibit the expression of collagens in liver tissues and decrease the expression ratios of p-PI3K/PI3K, p-Akt/Akt and p-mTOR/mTOR proteins in liver tissues. AS-IV can inhibit the inflammatory response so as to reduce the expression of collagens, and its mechanism may play a key role by inhibiting the PI3K/Akt/mTOR signaling pathway.

Pre-conditions for eliminating mitochondrial dysfunction and maintaining liver function after hepatic ischaemia reperfusion

The liver, the largest organ with multiple synthesis and secretion functions in mammals, consists of hepatocytes and Kupffer, stem, endothelial, stellate and other parenchymal cells. Because of early and extensive contact with the external environment, hepatic ischaemia reperfusion (IR) may result in mitochondrial dysfunction, autophagy and apoptosis of cells and tissues under various pathological conditions. Because the liver requires a high oxygen supply to maintain normal detoxification and synthesis functions, it is extremely susceptible to ischaemia and subsequent reperfusion with blood. Consequently, hepatic IR leads to acute or chronic liver failure and significantly increases the total rate of morbidity and mortality through multiple regulatory mechanisms. An increasing number of studies indicate that mitochondrial structure and function are impaired after hepatic IR, but that the health of liver tissues or liver grafts can be effectively rescued by attenuation of mitochondrial dysfunction. In this review, we mainly focus on the subsequent therapeutic interventions related to the conservation of mitochondrial function involved in mitigating hepatic IR injury and the potential mechanisms of protection. Because mitochondria are abundant in liver tissue, clarification of the regulatory mechanisms between mitochondrial dysfunction and hepatic IR should shed light on clinical therapies for alleviating hepatic IR‐induced injury.

Research review on the pharmacological effects of astragaloside IV

Astragalus membranaceus Bunge has been used to treat numerous diseases for thousands of years. As the main active substance of Astragalus membranaceus Bunge, astragaloside IV (AS-IV) also demonstrates the potent protective effect on focal cerebral ischemia/reperfusion, cardiovascular disease, pulmonary disease, liver fibrosis, and diabetic nephropathy. Based on studies published during the past several decades, the current state of AS-IV research and the pharmacological effects are detailed, elucidated, and summarized. This review systematically summarizes the pharmacological effects, metabolism mechanism, and the toxicity of AS-IV. AS-IV has multiple pharmacologic effects, including anti-inflammatory, antifibrotic, antioxidative stress, anti-asthma, antidiabetes, immunoregulation, and cardioprotective effect via numerous signaling pathways. According to the existing studies and clinical practices, AS-IV possesses potential for broad application in many diseases.

Astragaloside IV ameliorates renal injury in db/db mice

Diabetic nephropathy is a lethal complication of diabetes mellitus and a major type of chronic kidney disease. Dysregulation of the Akt pathway and its downstream cascades, including mTOR, NFκB, and Erk1/2, play a critical role in the development of diabetic nephropathy. Astragaloside IV is a major component of Huangqi and exerts renal protection in a mouse model of type 1 diabetes. The current study was undertaken to investigate the protective effects of diet supplementation of AS-IV on renal injury in db/db mice, a type 2 diabetic mouse model. Results showed that administration of AS-IV reduced albuminuria, ameliorated changes in the glomerular and tubular pathology, and decreased urinary NAG, NGAL, and TGF-β1 in db/db mice. AS-IV also attenuated the diabetes-related activation of Akt/mTOR, NFκB, and Erk1/2 signaling pathways without causing any detectable hepatotoxicity. Collectively, these findings showed AS-IV to be beneficial to type 2 diabetic nephropathy, which might be associated with the inhibition of Akt/mTOR, NFκB and Erk1/2 signaling pathways.

Kupffer cells and liver transplantation

Nowadays, liver transplantation is globally considered the most effective treatment for end-stage liver diseases. Ischemia-reperfusion (I/R) injury and immune rejection response (IRR) are the two major imperfections which severely affect the recipients' prognosis and survival rate without satisfactory clinical management strategies. Therefore, exploring effective methods to improve I/R injury and IRR have important clinical significance under circumstances of shortage of donor livers. Kupffer cells (KCs) are the largest population of antigen representing cells (APCs) which settle in the liver. As the first defensive line of the live, KCs exhibit various biological effects. However, the exact mechanisms responsible for the role of KCs in I/R injury and IRR remain elusive. We hereby review the current finding about the role of KCs in I/R injury and IRR.

Astragaloside IV attenuates injury caused by myocardial ischemia/reperfusion in rats via regulation of toll-like receptor 4/nuclear factor-κB signaling pathway

Myocardial ischemia/reperfusion (MI/R) injury, in which inflammatory response and cell apoptosis play a vital role, is frequently encountered in clinical practice. Astragaloside IV (AsIV), a small molecular saponin of Astragalus membranaceus, has been shown to confer protective effects against many cardiovascular diseases. The present study was aimed to investigate the antiinflammatory and antiapoptotic effects and the possible mechanism of AsIV on MI/R injury in rats. Rats were randomly divided into sham operation group, MI/R group and groups with combinations of MI/R and different doses of AsIV. The results showed that the expressions of myocardial toll-like receptor 4 (TLR4) and nuclear factor-κB (NF-κB) were significantly increased, and apoptosis of cardiomyocytes was induced in MI/R group compared with that in sham operation group. Administration of AsIV attenuated MI/R injury, downregulated the expressions of TLR4 and NF-κB and inhibited cell apoptosis as evidenced by decreased terminal deoxynucleotidyl transferase dUTP nick end labeling positive cells, B-cell lymphoma-2 associated X protein and caspase-3 expressions and increased B-cell lymphoma-2 expression compared with that in MI/R group. In addition, AsIV treatment reduced levels of inflammatory cytokines induced by MI/R injury. In conclusion, our results demonstrated that AsIV downregulates TLR4/NF-κB signaling pathway and inhibits cell apoptosis, subsequently attenuating MI/R injury in rats.

HIF-1α signaling activation by post-ischemia treatment with astragaloside IV attenuates myocardial ischemia-reperfusion injury

In this study, we evaluated the effect of astragaloside IV (Ast IV) post-ischemia treatment on myocardial ischemia-reperfusion (IR) injury (IRI). We also examined whether hypoxia inducible factor-1α (HIF-1α) and its downstream gene-inducible nitric oxide (NO) synthase (iNOS) play roles in the cardioprotective effect of Ast IV. Cultured cardiomyocytes and perfused isolated rat hearts were exposed to Ast IV during reperfusion in the presence or absence of the HIF-1α inhibitor 2-methoxyestradiol (2-MeOE2). The post-ischemia treatment with Ast IV protected cardiomyocytes from the apoptosis and death induced by simulated IRI (SIRI). Additionally, in cardiomyocytes, 2-MeOE2 and HIF-1α siRNA treatment each not only abolished the anti-apoptotic effect of post-ischemia treatment with Ast IV but also reversed the upregulation of HIF-1α and iNOS expression. Furthermore, after treatment with Ast IV, post-ischemic cardiac functional recovery and lactate dehydrogenase (LDH) release in the coronary flow (CF) were improved, and the myocardial infarct size was decreased. Moreover, the number of apoptotic cells was reduced, and the upregulation of the anti-apoptotic protein Bcl2 and downregulation of the pro-apoptotic protein Caspase3 were reversed. 2-MeOE2 reversed these effects of Ast IV on IR-injured hearts. These results suggest that post-ischemia treatment with Ast IV can attenuate IRI by upregulating HIF-1α expression, which transmits a survival signal to the myocardium.

Pharmacokinetics and tolerance of toal astragalosides after intravenous infusion of astragalosides injection in healthy Chinese volunteers

Total astragalosides (TA) are the principal active constituents isolated from Radix Astragali, which has been extensively used in the traditional Chinese medicine for hundreds of years. However, few detailed pharmacokinetic studies about TA or its main component in human have been done to date. The aim of this study was to investigate the pharmacokinetic (PK) characteristics of astragaloside IV (AGS-IV), the primary ingredient of TA, and tolerance of TA after single- and multi-intravenous infusion of astragalosides injection (AI) in healthy Chinese volunteers. A LC-MS/MS assay was developed for AGS-IV determination in human plasma and urine, and the PK parameters were estimated using non-compartmental methods. The mean maximum plasma concentration (Cmax) values of AGS-IV were 2.12, 3.59, 3.71 and 5.17 μg ml(-1) after single doses of 200, 300, 400 and 500 ml of AI, respectively. The corresponding mean values of area under the plasma concentration (AUC(0-∞)) were 4.38, 9.75, 13.59 and 18.22 μg h ml(-1), respectively, and the mean values of elimination half-life (t1/2) were 2.14, 2.59, 2.62 and 2.69 h, respectively. In the repeated dose study, no significant difference was observed between the PK parameters, peak time (Tmax), t1/2 and AUC, of day 1 and day 7. Cumulative urinary excretion of AGS-IV was 3.91% within 24 h after administration of 500 ml AI. AI was safe and well tolerated, and the adverse events, such as raised total bilirubin and rash, were mild and resolved spontaneously. In summary, the pharmacokinetic properties of AGS-IV are based on linear pharmacokinetics over the doses ranging from 200 to 500 ml of AI. No accumulation of AGS-IV was observed after repeated administration of AI once daily. AI was safe and well tolerated in this study, although cases of transient adverse events were observed.

The experimental study of Astragalus membranaceus on meridian tropsim: the distribution study of astragaloside IV in rat tissues

According to Traditional Chinese Medicine (TCM) theories, TCM with different meridian tropism have different therapeutic effects. In view of the meridian tropism of Astragalus membranaceus (Huangqi), astragaloside IV, one of the effective phytochemicals of Huangqi, was appointed and observed its distribution in rat tissues following a single intravenous (i.v.) dose. A simple and accurate LC-ESI-MS/MS method was developed and validated for astragaloside IV quantification in heart, liver, spleen, lung and kidney using warfarin as an internal standard (IS). Chromatographic separation was performed on a Eclipse plus C18 (4.6mm×100mm, 1.8μm) when the flow rate was set at 0.300mLmin(-1) and ammonium acetate aqueous solution - acetonitrile was used as mobile phase. The intra- and inter-day precisions of the quality control samples were within 15% and accuracies were within 90.0-110%. The recoveries were more than 90.0% at high, medium and low concentrations, respectively. This method was successfully applied for distribution of astragaloside IV after intravenous (i.v.) dose of 4mgkg(-1) astragaloside IV in rats. Astragaloside IV concentration was highest in liver and kidney and remained much higher than that in other tissues over the experiment course. Lung, heart and spleen were also detected to contain astragaloside IV. The results clearly demonstrated that astragaloside IV was one of the material bases of the meridian tropism of Huangqi.