Astragaloside IV attenuates glycated albumin-induced epithelial-to-mesenchymal transition by inhibiting oxidative stress in renal proximal tubular cells

Possible mechanism for the protective effect of active ingredients of astragalus membranaceus on diabetes nephropathy

Astragali Radix (AR), a common traditional Chinese medicinal herb, exhibits protective effects on diabetic nephropathy (DN) in extensive researches. Aticles focusing on AR in PubMed were collected and reviewed in order to summarize the latest pharmacological effects on DN. The action mechanisms for protectiving effects of AR were associated with regulation of anti-fibrosis, anti-inflammation, anti-oxidative stress, anti-podocyte apoptosis, restoration of mitochondrial function, restoration of endothelial function in diabetes nephropathy experimental models. Consequently, AR hold promise as potential novel therapeutics for the treatment of DN.

Glycated Albumin and Adverse Clinical Outcomes in Patients With CKD: A Prospective Cohort Study

RATIONALE & OBJECTIVE

Hemoglobin A1c (HbA1c) is widely used to estimate glycemia, yet it is less reliable in patients with chronic kidney disease (CKD). There is growing interest in the complementary use of glycated albumin (GA) to improve glycemic monitoring and risk stratification. However, whether GA associates with clinical outcomes in a non-dialysis-dependent CKD population remains unknown.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

3,110 participants with CKD from the Chronic Renal Insufficiency Cohort study.

EXPOSURE

Baseline GA levels.

OUTCOME

Incident end-stage kidney disease (ESKD), cardiovascular disease (CVD) events, and all-cause mortality.

ANALYTICAL APPROACH

Cox proportional hazards regression.

RESULTS

Participant characteristics included mean age 59.0±10.8 SD years; 1,357 (43.6%) female; and 1,550 (49.8%) with diabetes. The median GA was 18.7% (IQR, 15.8%-23.3%). During an average 7.9-year follow-up, there were 980 ESKD events, 968 CVD events, and 1,084 deaths. Higher GA levels were associated with greater risks of all outcomes, regardless of diabetes status: hazard ratios for ESKD, CVD, and death among participants with the highest quartile compared with quartile 2 (reference) were 1.42 (95% CI, 1.19-1.69), 1.67 (95% CI, 1.39-2.01), and 1.63 (95% CI, 1.37-1.94), respectively. The associations with CVD and death appeared J-shaped, with increased risk also seen at the lowest GA levels. Among patients with coexisting CKD and diabetes, the associations of GA with outcomes remained significant even after adjusting for HbA1c. For each outcome, we observed a significant increase in the fraction of new prognostic information when both GA and HbA1c were added to models.

LIMITATIONS

Lack of longitudinal GA measurements; and HbA1c measurements were largely unavailable in participants without diabetes.

CONCLUSIONS

Among patients with CKD, GA levels were independently associated with risks of ESKD, CVD, and mortality, regardless of diabetes status. GA added prognostic value to HbA1c among patients with coexisting CKD and diabetes.

PLAIN-LANGUAGE SUMMARY

Hemoglobin A1c (HbA1c) is widely used to estimate glycemia, yet it is less reliable in patients with chronic kidney disease (CKD). There is growing interest in the complementary use of glycated albumin (GA) to improve glycemic monitoring and risk stratification. However, whether GA associates with clinical outcomes in a non-dialysis-dependent CKD population remains unknown. In this cohort study of 3,110 individuals with non-dialysis-dependent CKD, GA levels were independently associated with risks of end-stage kidney disease, cardiovascular disease (CVD), and mortality. The associations with CVD and mortality appeared to be J-shaped. Among patients with coexisting CKD and diabetes, GA added prognostic value to HbA1c. Thus, GA may be a valuable complementary test to HbA1c in patients with CKD.

Research progress of astragaloside IV in treating acute kidney injury

Acute kidney injury (AKI) is one of the most common clinical critical illnesses, with decreased glomerular filtration rate, retention of nitrogen products, water and electrolyte disorders, and acid-base imbalance as the main clinical manifestations. Presently, there is no effective treatment for acute kidney injury, but the main treatment is to cure the primary disease, remove risk factors, maintain acid-base and water-electrolyte balance, and undergo kidney replacement. However, the mortality rate is still high. Investigations and studies showed that the mortality rate of patients with acute kidney injury in the ICU is 5-80% [1]. In recent years, Chinese medicine has been widely used in acute kidney injury treatment due to its complete dialectical system and rich experience. Astragalus is a commonly used medicine in traditional Chinese medicine to treat acute kidney injury. Astragaloside IV is the main active component of traditional Chinese medicine, Astragalus membranaceus. This article summarizes the relevant studies on treating acute kidney injury with astragaloside IV.

A systematic review of astragaloside IV effects on animal models of diabetes mellitus and its complications

Context

Diabetes mellitus (DM) is one of the fastest-growing diseases worldwide; however, its pathogenesis remains unclear. Complications seriously affect the quality of life of patients in the later stages of diabetes, ultimately leading to suffering. Natural small molecules are an important source of antidiabetic agents.

Objective

Astragaloside IV (AS-IV) is an active ingredient of Astragalus mongholicus (Fisch.) Bunge. We reviewed the efficacy and mechanism of action of AS-IV in animal and cellular models of diabetes and the mechanism of action of AS-IV on diabetic complications in animal and cellular models. We also summarized the safety of AS-IV and provided ideas and rationales for its future clinical application.

Methods

Articles on the intervention in DM and its complications using AS-IV, such as those published in SCIENCE, PubMed, Springer, ACS, SCOPUS, and CNKI from the establishment of the database to February 2022, were reviewed. The following points were systematically summarized: dose/concentration, route of administration, potential mechanisms, and efficacy of AS-IV in animal models of DM and its complications.

Results

AS-IV has shown therapeutic effects in animal models of DM, such as alleviating gestational diabetes, delaying diabetic nephropathy, preventing myocardial cell apoptosis, and inhibiting vascular endothelial dysfunction; however, the potential effects of AS-IV on DM should be investigated.

Conclusion

AS-IV is a potential drug for the treatment of diabetes and its complications, including diabetic vascular disease, cardiomyopathy, retinopathy, peripheral neuropathy, and nephropathy. In addition, preclinical toxicity studies indicate that it appears to be safe, but the safe human dose limit is yet to be determined, and formal assessments of adverse drug reactions among humans need to be further investigated. However, additional formulations or structural modifications are required to improve the pharmacokinetic parameters and facilitate the clinical use of AS-IV.

Pharmacological potential of Astragali Radix for the treatment of kidney diseases

BACKGROUND

With the increasing prevalence of hypertension, diabetes, and obesity, the incidence of kidney diseases is also increasing, resulting in a serious public burden. Conventional treatments for kidney diseases have unsatisfactory effects and are associated with adverse reactions. Traditional Chinese medicines have good curative effects and advantages over conventional treatments for preventing and treating kidney diseases. Astragali Radix is a Chinese herbal medicine widely used to treat kidney diseases.

PURPOSE

To review the potential applications and molecular mechanisms underlying the renal protective effects of Astragali Radix and its components and to provide direction and reference for new therapeutic strategies and future research and development of Astragali Radix.

STUDY DESIGN AND METHODS

PubMed, Google Scholar, and Web of Science were searched using keywords, including "Astragali Radix," "Astragalus," "Astragaloside IV" (AS-IV), "Astragali Radix polysaccharide" (APS), and "kidney diseases." Reports on the effects of Astragali Radix and its components on kidney diseases were identified and reviewed.

RESULTS

The main components of Astragali Radix with kidney-protective properties include AS-IV, APS, calycosin, formononetin, and hederagenin. Astragali Radix and its active components have potential pharmacological effects for the treatment of kidney diseases, including acute kidney injury, diabetic nephropathy, hypertensive renal damage, chronic glomerulonephritis, and kidney stones. The pharmacological effects of Astragali Radix are manifested through the inhibition of inflammation, oxidative stress, fibrosis, endoplasmic reticulum stress, apoptosis, and ferroptosis, as well as the regulation of autophagy.

CONCLUSION

Astragali Radix is a promising drug candidate for treating kidney diseases. However, current research is limited to animal and cell studies, underscoring the need for further verifications using high-quality clinical data.

Could Cyclosiversioside F Serve as a Dietary Supplement to Prevent Obesity and Relevant Disorders?

Obesity is the basis of numerous metabolic diseases and has become a major public health issue due to its rapidly increasing prevalence. Nevertheless, current obesity therapeutic strategies are not sufficiently effective, so there is an urgent need to develop novel anti-obesity agents. Naturally occurring saponins with outstanding bio-activities have been considered promising drug leads and templates for human diseases. Cyclosiversioside F (CSF) is a paramount multi-functional saponin separated from the roots of the food-medicinal herb Astragali Radix, which possesses a broad spectrum of bioactivities, including lowering blood lipid and glucose, alleviating insulin resistance, relieving adipocytes inflammation, and anti-apoptosis. Recently, the therapeutic potential of CSF in obesity and relevant disorders has been gradually explored and has become a hot research topic. This review highlights the role of CSF in treating obesity and obesity-induced complications, such as diabetes mellitus, diabetic nephropathy, cardiovascular and cerebrovascular diseases, and non-alcoholic fatty liver disease. Remarkably, the underlying molecular mechanisms associated with CSF in disease therapy have been partially elucidated, especially PI3K/Akt, NF-κB, MAPK, apoptotic pathway, TGF-β, NLRP3, Nrf-2, and AMPK, with the aim of promoting the development of CSF as a functional food and providing references for its clinical application in obesity-related disorders therapy.

Pharmacological Effects of Astragaloside IV: A Review

Astragaloside IV (AS-IV) is one of the main active components extracted from the Chinese medicinal herb Astragali and serves as a marker for assessing the herb's quality. AS-IV is a tetracyclic triterpenoid saponin in the form of lanolin ester alcohol and exhibits various biological activities. This review article summarizes the chemical structure of AS-IV, its pharmacological effects, mechanism of action, applications, future prospects, potential weaknesses, and other unexplored biological activities, aiming at an overall analysis. Papers were retrieved from online electronic databases, such as PubMed, Web of Science, and CNKI, and data from studies conducted over the last 10 years on the pharmacological effects of AS-IV as well as its impact were collated. This review focuses on the pharmacological action of AS-IV, such as its anti-inflammatory effect, including suppressing inflammatory factors, increasing T and B lymphocyte proliferation, and inhibiting neutrophil adhesion-associated molecules; antioxidative stress, including scavenging reactive oxygen species, cellular scorching, and regulating mitochondrial gene mutations; neuroprotective effects, antifibrotic effects, and antitumor effects.

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 beneficial effects of astragaloside IV on ameliorating diabetic kidney disease

Diabetic kidney disease (DKD) has become the major cause of chronic kidney disease or end-stage renal disease. There is still a need for innovative treatment strategies for preventing, arresting, treating, and reversing DKD, and a plethora of scientific evidence has revealed that Chinese herbal monomers can attenuate DKD in multiple ways. Astragaloside IV (AS-IV) is one of the active ingredients of Astragalus membranaceus and was selected as a chemical marker in the Chinese Pharmacopeia for quality control purposes. An increasing amount of studies indicate that AS-IV is a promising novel drug for the treatment of DKD. AS-IV has been shown to improve DKD by combating oxidative stress, attenuating endoplasmic reticulum stress, regulating calcium homeostasis, alleviating inflammation, improving vascular function, improving epithelial to mesenchymal transition and so on. This review briefly summarizes the pathogenesis of DKD, systematically reviews the mechanisms by which AS-IV improves DKD, and aims to facilitate related pharmacological research and development to promote the utilization of Chinese herbal monomers in DKD.

Astragaloside IV attenuated TGF-β1- induced epithelial-mesenchymal transition of renal tubular epithelial cells via connexin 43 and Akt/mTOR signaling pathway

INTRODUCTION

The objective of the study was to observe whether connexin 43 (Cx43) could regulate epithelial mesenchymal transformation (EMT) of renal tubular epithelial cells (RTECs) by influencing Akt/mTOR signaling pathway, and whether ASV could inhibit the development of renal interstitial fibrosis by regulating Cx43.

METHODS

Lentivirus infection was transfected into RTECs with the final concentration of 50 ×PFU/ cell to regulate the expression of Cx43. And RTECs were intervened by different doses of Astragaloside IV (ASV). After synchronous culture of RTECs in each group，the expression levels of EMT-related indicators and Cx43 were detected by fluorescence microscope and Western-Blotting (WB), even the protein expressions and phosphorylation levels of AKT and mTOR in different groups were detected by WB.

RESULTS

When the expression of Cx43 in RTECs was regulated by lentivirus infection, the degree of EMT induced by TGF‑β1 and the phosphorylation level of Akt and mTOR were changed accordingly, indicating that Akt/mTOR pathway might be a downstream molecular mechanism by which Cx43 could regulate EMT. After intervention with different doses of ASV, the expression level of Cx43 increased with obvious concentration dependence, and the expression levels of p-Akt and p- mTOR were significantly altered, suggesting that ASV could effectively increase the protein expressions of TGF‑β1-induced Cx43 in RTECs and inhibit the phosphorylation levels of Akt and mTOR.

CONCLUSION

Cx43 were the main material basis of RTECs' injury, and ASV could inhibit TGF-β1- induced RTECs' transdifferentiation. In-depth study of the mechanism might provide a broad application prospect for the treatment of renal interstitial fibrosis.

Emerging medical therapies in crush syndrome - progress report from basic sciences and potential future avenues

Crush injury is a disease that is commonly found in victims of earthquakes, debris flows, mine disasters, explosions, terrorist attacks, local wars, and other accidents. The complications that arise due to the crush injury inflicted on victims give rise to crush syndrome (CS). If not treated in time, the mortality rate of CS is very high. The most important measure that can be taken to reduce mortality in such situations is to immediately start treatment. However, the traditional treatment methods such as fluid resuscitation, diuresis, and hemodialysis are not feasible enough to be carried out at the disaster scene. So there is a need for developing new treatments that are efficient and convenient. Because it is difficult to diagnose in the disaster area and reach the treatment equipment and treat on time. It has become a new research needs to be directed into identifying new medical treatment targets and methods using the etiology and pathophysiological mechanisms of CS. In recent years, a large number of new anti-oxidant and anti-inflammatory drug therapies have been shown to be highly efficacious in CS rat/mouse models. Some of them are expected to become specific drugs for the emergency treatment of a large number of patients who may develop CS in the aftermath of earthquakes, wars, and other disasters in the future. Hence, we have reviewed the latest research on the medical therapy of CS as a source for anyone wishing to pursue research in this direction.

Astragaloside IV attenuates high glucose-induced EMT by inhibiting the TGF-β/Smad pathway in renal proximal tubular epithelial cells

In the present study, we examined the molecular mechanism of astragaloside IV (AS-IV) in high glucose (HG)-induced epithelial-to-mesenchymal transition (EMT) in renal proximal tubular epithelial cells (PTCs). NRK-52E cell viability and apoptosis were determined by the cell counting kit-8 (CCK-8) assay and flow cytometric analysis, respectively. Expressions of E-cadherin, N-cadherin, vimentin, and occludin were measured by Western blot, and those of E-cadherin and N-cadherin were additionally measured by immunofluorescence analysis. Transforming growth factor-β1 (TGF-β1) and α-smooth muscle actin (α-SMA) expressions were detected by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot. The expressions of Smad2, Smad3, phosphorylated-Smad2 (p-Smad2), and p-Smad3 were measured using Western blot. We found that AS-IV could recover NRK-52E cell viability and inhibit HG-induced cell apoptosis. TGF-β1, α-SMA, Smad2, Smad3, p-Smad2, and p-Smad3 expressions were decreased in the AS-IV-treated groups compared with the HG group. Moreover, the expressions of E-cadherin and occludin were remarkably up-regulated and those of N-cadherin and vimentin were down-regulated in the AS-IV-treated groups compared with the HG group. Interestingly, the TGF-β1 activator SRI-011381 hydrochloride had an antagonistic effect to AS-IV on HG-induced EMT behavior. In conclusion, AS-IV attenuates HG-induced EMT by inhibiting the TGF-β/Smad pathway in renal PTCs.

Astragaloside IV alleviates PM2.5-induced lung injury in rats by modulating TLR4/MyD88/NF-κB signalling pathway

OBJECTIVE

Astragaloside IV (AS IV) is antioxidant and anti-inflammatory product, which is extracted from the Chinese herb Astragalus membranaceus. It is widely used in a variety of inflammatory diseases. The research was to explored the protective effects of AS IV against lung injury induced by particulate matter 2.5 (PM2.5) in vivo.

SUBJECTS AND METHODS

Thirty-five male Sprague-Dawley rats were randomly divided into five groups (n=7 per group). (1) Normal saline group (NS), (2) AS IV group (AS) (100 mg/kg), (3) PM2.5 group (PM2.5), (4) PM2.5 + AS IV group (ASL) (50 mg/kg), and (5) PM2.5 + AS IVgroup (ASH) (100 mg/kg). Rats were pre-treated with AS IV intraperitoneally (50 and 100 mg/kg/day) for three days. Then, PM2.5 (7.5 mg/kg) was given by intratracheal instillation to induce lung injury. Six hours after PM2.5 stimulation, the rats were euthanized. Bronchoalveolar lavage fluid (BALF) was collected for assay of cytokines. Lung tissue was collected for oxidative stress, histology, immunohistochemistry, transmission electron microscope, and western blot analyses.

RESULTS

AS IV alleviated PM2.5-induced lung injury by decreasing lung dry-wet ratio, reducing the level of interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-α), and C-reactive protein (CRP) in BALF, and reduced oxidative stress response in lung tissue. Western blot results revealed that AS-IV regulated the expression of TLR4/MyD88/NF-κB pathway proteins in lung tissues.

CONCLUSION

AS IV mitigated PM2.5 induced lung injury by regulating the activity of TLR4/MyD88/NF-κB signalling pathway, reducing inflammatory and oxidative stress responses.

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 Protects Against Oxidative Stress in Calf Small Intestine Epithelial Cells via NFE2L2-Antioxidant Response Element Signaling

Oxidative stress can damage intestinal epithelial cell integrity and function, causing gastrointestinal disorders. Astragaloside IV (ASIV) exhibits a variety of biological and pharmacological properties, including anti-inflammatory and antioxidant effects. The purpose of this research was to investigate the cytoprotective action of ASIV and its mechanisms in calf small intestine epithelial cells with hydrogen peroxide (H₂O₂)-induced oxidative stress. ASIV pretreatment not only increased cell survival, but it also decreased reactive oxygen species generation and apoptosis, enhanced superoxide dismutase, catalase, and glutathione peroxidase levels, and it reduced malondialdehyde formation. Furthermore, pretreatment with ASIV elevated the mRNA and protein levels of nuclear factor erythroid 2-related factor 2 (NFE2L2), heme oxygenase-1 (HMOX1), and NAD(P)H quinone dehydrogenase 1 (NQO1). The NFE2L2 inhibitor ML385 inhibited NFE2L2 expression and then blocked HMOX1 and NQO1 expression. These results demonstrate that ASIV treatment effectively protects against H₂O₂-induced oxidative damage in calf small intestine epithelial cells through the activation of the NFE2L2-antioxidant response element signaling pathway.

Astragaloside IV (AS-IV) alleviates the malignant biological behavior of hepatocellular carcinoma via Wnt/β-catenin signaling pathway

Astragaloside IV (AS-IV) is an active substance isolated from Astragalus membranaceus (Fisch.) Bungede, which has been shown to have pharmacological effects in a variety of cancers. However, the effects of AS-IV in hepatocellular carcinoma (HCC) and its related mechanisms have been poorly understood. In this study, we explored the roles of AS-IV on HCC and the underlying signaling pathway. We reported that the appropriate concentrations of AS-IV (25, 50, 100 nmol l-1) significantly suppressed the proliferation and cell cycle of HepG2 and Hep3B cell lines whilst promoting apoptosis. Besides, a trans-well and wound healing assay showed that AS-IV could markedly inhibit the migration and invasion of HepG2 and Hep3B cells, the expression of E-cadherin was up-regulation but the expression of N-cadherin and vimentin was down-regulation, and the protein levels of cleaved-caspase-3, 9 were increased markedly compared with the corresponding control. Furthermore, animal model treatment revealed that AS-IV could effectively reduce tumor formation. Moreover, AS-IV also significantly weakened the expression of Wnt, β-catenin and TCF-4 in vitro and in vivo. Taken together, these results suggested that AS-IV inhibited the biological processes of HCC via regulating of the Wnt/β-catenin pathway.

Astragaloside IV attenuates renal fibrosis through repressing epithelial-to-mesenchymal transition by inhibiting microRNA-192 expression: in vivo and in vitro studies

The aim of this study was to investigate the effect of Astragaloside IV (AS-IV) on renal fibrosis in vivo and in vitro, and further to explore the underlying mechanism. To investigate the effect of AS-IV treatment on renal fibrosis in vivo, mouse renal fibrosis model was established by performing unilateral ureteral occlusion (UUO). The mice in the intervention group of AS-IV were given AS-IV 20 mg/(kg/d) on the day after surgery for 7 consecutive days. Then renal sections were stained with hematoxylin and eosin (H&E) to evaluate the degree of fibrosis. For in vitro study, human kidney tubular epithelial cells induced by (TGF-β1) were performed to research the protective role of AS-IV in anti-fibrosis. Results form the in vivo study showed that AS-IV treatment in UUO mice significantly reduced parenchymal loss and tubular atrophy, indicating that AS-IV treatment attenuated renal fibrosis caused by UUO. TGF-β1 treatment significantly increased the expression of α-SMA, vimentin, collagen I, miR-192 and decreased E-cadherin expression in HK-2 cells, suggesting that TGF-β1 stimulated renal tubulointerstitial fibrosis. Moreover, in TGF-β1 stimulated HK-2 cells, AS-IV clearly inhibited the expression levels of α-SMA, vimentin, collagen I, and miR-192 in a dose-dependent fashion while increased the expression level of E-cadherin in the same manner, indicating that AS-IV functioned the inhibitory role in renal tubulointerstitial fibrosis. Interestingly, we noted that ZEB2 was a direct target of miR-192. The effects of AS-IV on the expression of α-SMA, vimentin, collagen I and E-cadherin were inhibited by miR-192 mimic and aggravated by miR-192 inhibitor. Taken together, our results provided evidence that AS-IV could effectively protect kidney against epithelial fibrosis, and this renoprotective effect involved miR-192. Therefore, AS-IV might be considered as a potential and promising candidate drug for the treatment of renal epithelial fibrosis.

Astragaloside IV Protects Ethanol-Induced Gastric Mucosal Injury by Preventing Mitochondrial Oxidative Stress and the Activation of Mitochondrial Pathway Apoptosis in Rats

Alcohol consumption affects gastric mucosa by multiple and complex mechanisms depending either by direct contact of ethanol or by indirect biological damage induced by its metabolite acetaldehyde. The present study aims at further investigating the mechanism of ethanol-induced gastric mucosa injury and the protective effect of astragaloside IV (AS-IV) in an aspect of mitochondrial oxidative stress and mitochondrial pathway of apoptosis. Using an array of experimental approaches, we have shown that the development of mitochondrial oxidative stress and associated apoptosis play crucial roles in the pathogenesis of gastric injury induced by ethanol. AS-IV inhibits mitochondrial oxidative stress by scavenging accumulation of malondialdehyde and decreasing the consumption of glutathione. AS-IV also prevents ethanol-induced apoptosis by modulating the activity of caspase-3 and caspase-9, the expression of Bax/Bcl-2, and the release of cytochrome C and apoptosis inducing factor. Moreover, AS-IV reduces ethanol-mediated activation of caspase-8 and breakage of Bid. This study thus indicates that AS-IV prevented ethanol-induced gastric damage by blocking activation of mitochondrial oxidative stress and mitochondrial pathway of apoptosis induced by ethanol in the gastric mucosa.

Chinese herbal medicine for diabetic kidney disease: a systematic review and meta-analysis of randomised placebo-controlled trials

OBJECTIVES

To provide a broad evaluation of the efficacy and safety of oral Chinese herbal medicine (CHM) as an adjunctive treatment for diabetic kidney disease (DKD), including mortality, progression to end-stage kidney disease (ESKD), albuminuria, proteinuria and kidney function.

DESIGN

A systematic review and meta-analysis.

METHODS

Randomised controlled trials (RCTs) comparing oral CHM with placebo as an additional intervention to conventional treatments were retrieved from five English (Cochrane Central Register of Controlled Trials, MEDLINE, Embase, Allied and Complementary Medicine Database and Cumulative Index of Nursing and Allied Health Literature) and four Chinese databases (China BioMedical Literature, China National Knowledge Infrastructure, Chonqing VIP and Wanfang) from inception to May 2018. RCTs recruiting adult DKD patients induced by primary diabetes were considered eligible, regardless of the form and ingredients of oral CHM. Mean difference (MD) or standardised mean difference (SMD) was used to analyse continuous variables and RR for dichotomous data.

RESULTS

From 7255 reports retrieved, 20 eligible studies involving 2719 DKD patients were included. CHM was associated with greater reduction of albuminuria than placebo, regardless of whether renin-angiotensin system (RAS) inhibitors were concurrently administered (SMD -0.56, 95% CI [-1.04 to -0.08], I²=64%, p=0.002) or not (SMD -0.92, 95% CI [-1.35 to -0.51], I²=87%, p<0.0001). When CHM was used as an adjunct to RAS inhibitors, estimated glomerular filtration rate was higher in the CHM than placebo group (MD 6.28 mL/min; 95% CI [2.42 to 10.14], I²=0%, p=0.001). The effects of CHM on progression to ESKD and mortality were uncertain due to low event rates. The reported adverse events in CHM group included digestive disorders, elevated liver enzyme level, infection, anaemia, hypertension and subarachnoid haemorrhage, but the report rates were low and similar to control groups. The favourable results of CHM should be balanced with the limitations of the included studies such as high heterogeneity, short follow-up periods, small numbers of clinical events and older patients with less advanced disease.

CONCLUSIONS

Based on moderate to low quality evidence, CHM may have beneficial effects on renal function and albuminuria beyond that afforded by conventional treatment in adults with DKD. Further well-conducted, adequately powered trials with representative DKD populations are warranted to confirm the long-term effect of CHM, particularly on clinically relevant outcomes.

PROSPERO REGISTRATION NUMBER

CRD42015029293.

Astragaloside IV inhibits glucose-induced epithelial-mesenchymal transition of podocytes through autophagy enhancement via the SIRT-NF-κB p65 axis

Both autophagy and podocyte epithelial-mesenchymal transition (EMT) are critical factors in glomerular diseases that involve proteinuria and fibrosis. Here, we sought to determine whether plant-derived saponin astragaloside IV (AS-IV) was able to reverse renal fibrosis and improve renal function through regulation of autophagy and podocyte EMT. Cultured immortalized mouse podocytes and KK-Ay mice models of diabetes were exposed to AS-IV. Western blotting, real-time PCR, immunofluorescence and histochemistry were used to analyze markers of autophagy and podocyte EMT. We observed that AS-IV inhibited glucose-induced podocyte EMT and enhanced autophagy by decreasing NF-κB subunit p65 acetylation as well as increasing Sirtuin1 (SIRT1) expression. Treatment of the cells and animal models with a SIRT1 inhibitor EX527 was able to reverse these effects. The SIRT1 activator SRT1720 was also found to decrease p65 acetylation and enhance autophagy in glucose-induced podocyte EMT. Additionally, further treatment with autophagy inhibitor 3-methyladenine was able to reverse the effects of AS-IV on podocyte EMT, while the autophagy activator rapamycin or the NF-κB pathway inhibitor ammonium pyrrolidinedithiocarbamate (PDTC) were able to reverse glucose-induced podocyte EMT. Notably, both renal fibrosis and renal function in diabetic KK-Ay mice were improved after treatment with AS-IV. These findings support AS-IV as a renoprotective agent that likely exerts its effects on podocyte EMT through modulation of the SIRT1-NF-κB pathway and autophagy activation. Further studies are required to clarify the role of AS-IV as a potential therapeutic agent in glomerular diseases.

Astragalus membranaceus and Panax notoginseng, the Novel Renoprotective Compound, Synergistically Protect against Podocyte Injury in Streptozotocin-Induced Diabetic Rats

This study was aimed at investigating the synergistical protective effects of Astragalus membranaceus (AG) and Panax notoginseng (NG) on podocyte injury in diabetic rats. Diabetes was induced in rats by a single intraperitoneal injection of streptozotocin at 55 mg/kg. Diabetic rats were then orally administrated with losartan, AG, NG, and AG plus NG (2 : 1) for 12 weeks. Albuminuria, biochemical markers, renal histopathology, and podocyte number per glomerulus were measured. Podocyte apoptosis was determined by triple immunofluorescence labeling including TUNEL assay, WT1, and DAPI. Renal expression of nephrin, α-dystroglycan, Bax, Bcl-xl, and Nox4 was evaluated by immunohistochemistry, western blot, and RT-PCR. AG plus NG ameliorated albuminuria, renal histopathology, and podocyte foot process effacement to a greater degree than did AG or NG alone. The number of podocytes per glomerulus, as well as renal expression of nephrin, α-dystroglycan, and Bcl-xl, was decreased, while podocyte apoptosis, as well as renal expression of Bax and Nox4, was increased in diabetic rats. All of these abnormalities were partially restored by AG plus NG to a greater degree than did AG or NG alone. In conclusion, AG and NG synergistically ameliorated diabetic podocyte injury partly through upregulation of nephrin, α-dystroglycan, and Bcl-xl, as well as downregulation of Bax and Nox4. These findings might provide a novel treatment combination for DN.

Astragaloside IV inhibits lung cancer progression and metastasis by modulating macrophage polarization through AMPK signaling

BACKGROUND

Accumulating evidence suggests that M2-polarized tumor-associated macrophages (TAMs) play an important role in cancer progression and metastasis, making M2 polarization of TAMs an ever more appealing target for therapeutic intervention. Astragaloside IV (AS-IV), a saponin component isolated from Astragali radix, has been reported to inhibit the invasion and metastasis of lung cancer, but its effects on TAMs during lung cancer progression have not been investigated.

METHODS

Human THP-1 monocytes were induced to differentiate into M2 macrophages through treatments with IL-4, IL-13, and phorbol myristate acetate (PMA). We used the lung cancer cell lines A549 and H1299 cultured in conditioned medium from M2 macrophages (M2-CM) to investigate the effects of AS-IV on tumor growth, invasion, migration, and angiogenesis of lung cancer cells. Macrophage subset distribution, M1 and M2 macrophage-associated markers, and mRNA expression were analyzed by flow cytometry and quantitative PCR. The activation of adenosine monophosphate-activated protein kinase (AMPK) signaling pathways that mediate M2-CM-promoted tumor migration was detected using western blotting.

RESULTS

Here we found that AS-IV significantly inhibited IL-13 and IL-4-induced M2 polarization of macrophages, as illustrated by reduced expression of CD206 and M2-associated genes, and that AS-IV suppressed the M2-CM-induced invasion, migration, and angiogenesis of A549 and H1299 cells. In vivo experiments demonstrated that AS-IV greatly inhibited tumor growth and reduced the number of metastases of Lewis lung cancer. The percentage of M2 macrophages was decreased in tumor tissue after AS-IV treatment. Furthermore, AS-IV inhibited AMPKα activation in M2 macrophages, and silencing of AMPKα partially abrogated the inhibitory effect of AS-IV.

CONCLUSIONS

AS-IV reduced the growth, invasion, migration, and angiogenesis of lung cancer by blocking the M2 polarization of macrophages partially through the AMPK signaling pathway, which appears to play an important role in AS-IV's ability to inhibit the metastasis of lung cancer.

Astragaloside IV improves renal function and fibrosis via inhibition of miR-21-induced podocyte dedifferentiation and mesangial cell activation in diabetic mice

Background

Podocyte dedifferentiation and mesangial cell (MC) activation play an important role in many glomerular diseases associated with fibrosis. MicroRNA-21 (miR-21) is closely linked to renal fibrosis, but it is unknown whether and how miR-21 promotes podocyte dedifferentiation and MC activation and whether astragaloside IV (AS-IV) improves renal function and fibrosis through the regulation of miR-21.

Materials and methods

Cultured MCs, primary mouse podocytes, and diabetic KK-Ay mice were treated with AS-IV. Cell transfection, Western blot, real-time PCR, immunofluorescence assay, immunohistochemical assay, and electronic microscopy were used to detect the markers of podocyte dedifferentiation and MC activation and to observe the renal morphology.

Results

Our data showed that miR-21 expression was increased and that AS-IV decreased miR-21 levels in cells, serum, and kidney. Overexpressed miR-21 promoted podocyte dedifferentiation and MC activation, and treatment with AS-IV reversed this effect. Furthermore, the overexpression of miR-21 activated the β-catenin pathway and the transforming growth factor (TGF)-β1/Smads pathway in the process of podocyte dedifferentiation and MC activation, which was abolished by AS-IV treatment. In addition, both the Wnt/β-catenin pathway inhibitor XAV-939 and the TGF-β1/Smads pathway inhibitor SB431542 reversed the effect of AS-IV. Furthermore, AS-IV improved renal function and fibrosis in diabetic KK-Ay mice.

Conclusion

Our results indicated that AS-IV ameliorates renal function and renal fibrosis by inhibiting miR-21 overexpression-induced podocyte dedifferentiation and MC activation in diabetic kidney disease. These findings pave way for future studies investigating AS-IV as a potential therapeutic agent in the management of glomerular diseases.

Astragaloside IV ameliorates early diabetic nephropathy by inhibition of MEK1/2-ERK1/2-RSK2 signaling in streptozotocin-induced diabetic mice

Objective The aim of this study was to investigate the renoprotective effects and molecular mechanisms of astragaloside IV (AS-IV) in streptozotocin (STZ)-induced diabetic mice. Methods Male C57BL/6 mice were injected intraperitoneally with STZ at 200 mg/kg body weight. AS-IV was administered for 8 consecutive weeks, beginning 1 week after STZ injection. Body weight, 24-hour urinary albumin excretion, and fasting blood glucose were measured. Kidney tissues were examined by histopathological analyses. Total levels and phosphorylation of mitogen-activated protein kinase 1/2 (MEK1/2), extracellular signal-regulated kinases 1 and 2 (ERK1/2), and ribosomal S6 kinase 2 (RSK2) were determined by Western blotting analysis. Results AS-IV treatment significantly reduced albuminuria and serum creatinine levels, ameliorated mesangial matrix expansion and greater foot process width, and decreased the levels of urinary N-acetyl-beta-D-glucosaminidase, neutrophil gelatinase-associated lipocalin, and transforming growth factor-beta 1 in STZ-induced diabetic mice. AS-IV also inhibited renal cortical phosphorylation of MEK1/2, ERK1/2 and RSK2. Conclusion Our results suggest that AS-IV attenuates renal injury in STZ-induced diabetic mice. This effect might be partially associated with inhibition of the activation of the MEK1/2-ERK1/2-RSK2 signaling pathway.

Effects of astrogaloside on the inflammation and immunity of renal failure patients receiving maintenance dialysis

Chronic renal failure is a type of clinical syndrome originating from chronic renal diseases. The aim of the study was to investigate the effect of astrogaloside on the inflammation and immunity of renal failure patients receiving maintenance dialysis. We randomly selected 92 renal failure patients receiving maintenance dialysis who were admitted to hospital for treatment between May, 2015 and April, 2016. Patients were randomly divided into the control (n=46) and observation (n=46) groups. Patients in the control group received the regular dialysis plus the basic treatment in Western medicine, while in the observation group, patients additionally received astrogaloside via intravenous injection as treatment. We compared the clinical efficacy of patients between the two groups, residual renal function (RRF), changes in urine volume, variations in inflammatory indicators [C-reaction protein (CRP), interleukin-6 (IL-6), IL-17, and tumor necrosis factor-α (TNF-α)] before and after treatment, and the levels of the thymus-dependent lymphocyte (T cells) subgroup (CD3⁺, CD4⁺, CD8⁺ and CD4⁺/CD8⁺) in the immune system of patients after treatment. In the observation group, the total effective rate was significantly higher than that in the control group (P<0.05). After 6 months, RRF and the urine volume of patients in the two groups were decreased when compared with the levels before treatment, and the decreasing rates of RRF and urine volume in the observation group were significantly lower than those in the control group (P<0.05). After treatment, the levels of human serum C reaction protein (hs-CRP), IL-6, IL-17 and TNF-α in the two groups were lower than those before treatment, and the decrease in the observation group was more significant than that in the control group (P<0.05). Following treatment, the levels of CD3⁺, CD4⁺ and CD4⁺/CD8⁺ in the observation group were higher than those in the control group, and the level of CD8⁺ was lower than that in the control group (P<0.05). In conclusion, astrogaloside can delay the decrease in RRF of renal failure patients receiving the maintenance dialysis, ameliorate the inflammatory responses, and enhance the immune function, thereby increasing the disease resistance of patients and improving the clinical symptoms.

SIRT3 prevents angiotensin II-induced renal tubular epithelial-mesenchymal transition by ameliorating oxidative stress and mitochondrial dysfunction

Silent mating type information regulation 2 homolog 3 (SIRT3) is a major protective mediator that ameliorates oxidative stress and mitochondrial dysfunction, which are associated with the pathogenesis of epithelial-mesenchymal transition (EMT). The present study was aimed to investigate the potential role of SIRT3 in renal tubular EMT both in vitro and in vivo. Firstly, we showed that the expression of SIRT3 was repressed in angiotensin II-induced EMT. SIRT3 deficiency triggered EMT response, while over-expression of SIRT3 attenuated EMT response. In addition, over-expression of SIRT3 repressed AngⅡ-induced excessive production of mitochondrial superoxide, as well as mitochondrial dysfunction evidenced by the maintenance of mitochondrial number and morphology, and the stabilization of mitochondrial membrane potential. In conclusion, these findings identify a protective role of SIRT3 against angiotensin II-induced EMT in the kidney, and suggest SIRT3 upregulation is a potential therapeutic strategy for the treatment of renal tubulointerstitial fibrosis.

Astragaloside IV protects against the pathological cardiac hypertrophy in mice

Although pathologic hypertrophic hearts currently maintain output, sustained cardiac hypertrophy could predispose a patient to arrhythmia and sudden death, and also cause heart failure. Thus, finding effective treatment and exploring the underlying molecular mechanisms of cardiac hypertrophy is urgently necessary. Astragaloside IV (AST-IV) is the main active component, extracted from the traditional Chinese medicinal herb Astragalus membranaceus. Previous studies have indicated that AST-IV has various bioactivities, such as anti-cancer, anti-oxidative stress and anti-inflammation. In the present study, we aimed to explore the effects of AST-IV on cardiac hypertrophy induced by aortic banding (AB) surgery in mice, and to reveal the underlying signaling mechanisms. The suppressor of IKKε (SIKE) is a negative regulator of the interferon pathway, which could be enhanced by AST-IV to ameliorate pathological cardiac hypertrophy in mice through inactivating TANK-binding kinase 1 (TBK1)/PI3K/AKT signaling pathway. AST-IV attenuated cardiac hypertrophy, collagen accumulation and abnormal cardiac functions. In addition, AB-induced apoptosis and inflammation in the heart tissue samples of mice, which were attenuated by AST-IV administration through inhibiting SIKE expression levels. Together, the findings above indicated that AST-IV might be a potential candidate to prevent cardiac hypertrophy via elevating SIKE to suppress TBK1/PI3K/AKT activity.

Astragaloside-IV prevents acute kidney injury and inflammation by normalizing muscular mitochondrial function associated with a nitric oxide protective mechanism in crush syndrome rats

Background

Crush syndrome (CS) is a serious medical condition characterized by muscle cell damage resulting from decompression after compression (i.e., ischemia/reperfusion injury). A large number of CS patients develop cardiac failure, kidney dysfunction, and systemic inflammation, even when fluid therapy is administered. We evaluated whether the administration of astragaloside-IV (AS)-containing fluid improved survival by preventing kidney and muscular mitochondrial dysfunction in a rat model of CS.

Results

The CS model was generated by subjecting anesthetized rats to bilateral hind limb compression with a rubber tourniquet for 5 h. Rats were then randomly divided into four groups: (1) sham; (2) CS with no treatment; (3) CS with normal saline treatment; and (4) CS with normal saline + 10 mg/kg AS. AS-containing fluid improved kidney function by improving shock and metabolic acidosis in CS rats. In addition, there was a reduction in oxidative damage. The attenuation of hyperkalemia was significantly related to improving muscle injury via preventing mitochondrial dysfunction. Moreover, this mitochondria protection mechanism was related to the nitric oxide (NO) generated by activation of endothelial nitric oxide synthase, which provided an anti-oxidative and anti-inflammatory effect.

Conclusions

Treatment with AS-containing fluid led to a dramatic improvement in survival following CS because of direct and indirect anti-oxidative effects in the kidney, and improvements in mitochondrial dysfunction and inflammation owing to AS acting as an NO donor in injured muscle.

Electronic supplementary material

The online version of this article (doi:10.1186/s13613-017-0313-2) contains supplementary material, which is available to authorized users.

Astragaloside IV inhibits metastasis in hepatoma cells through the suppression of epithelial-mesenchymal transition via the Akt/GSK-3β/β-catenin pathway

Our previous studies demonstrated that traditional Chinese herbal medicine 'Songyou Yin' inhibited the growth and invasion of hepatocellular carcinoma (HCC) cells, and altered epithelial‑mesenchymal transition (EMT) markers in oxaliplatin‑treated HCC tissues and cell lines. In the present study, we aimed to explore whether astragaloside IV (AS-IV), a component of 'Songyou Yin', can affect the growth and invasion of HCC cells and the underlying mechanism involved. Human HCC cell lines Huh7 and MHCC97-H, with low and high metastatic potential, respectively, were treated with increasing doses of AS-IV. The Cell Counting Kit-8 (CCK-8), plate clone formation, Transwell, wound healing and immunofluorescence assays were used to investigate the effects of AS-IV on HCC cell proliferation, migration and invasion. The protein expression levels were analyzed by western blotting and immunofluorescence assay. The CCK-8 and plate clone formation assays showed that AS-IV had little effect on the proliferation of HCC cells in vitro. However, the Transwell and wound healing assays demonstrated that AS-IV inhibited the migration and invasion of HCC cells in a dose-dependent manner and the morphology of HCC cells was altered from spindle into oval shaped in the AS-IV pretreated groups. The upregulation of E-cadherin and downregulation of N-cadherin, vimentin, α-SMA and Slug were also observed in the AS-IV pretreated groups. Additionally, AS-IV treatment resulted in a profound decrease in the phosphorylated forms of Akt and GSK-3β, which in turn inhibited the expression of β-catenin. Thus, we conclude that AS-IV attenuates the invasive and migratory abilities of HCC cells through the inhibition of EMT by targeting the Akt/GSK-3β/β-catenin pathway.

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 protects cardiomyocytes from anoxia/reoxygenation injury by upregulating the expression of Hes1 protein

Astragaloside IV (ASI), a traditional Chinese medicine, is a main active ingredient of Astragalus membranaceus. Many clinical studies have found that ASI protects cardiomyocytes in cardiovascular diseases, but the underlying mechanisms remain obscure. The aim of this study was to investigate the molecular mechanisms responsible for the protective effects of ASI in cardiomyocytes from anoxia/reoxygenation (A/R) injury. According to the previous studies, we hypothesized that the cardioprotective effects of ASI against A/R injury might be associated with Notch1/Hes1 signaling pathway. In this study, neonatal rat primary cardiomyocytes were preconditioned with ASI prior to A/R injury. Our results showed that ASI effectively increased the cell viability, decreased the content of MDA, decreased the activities of CPK and LDH, increased the activities of GSH-Px and SOD, and reduced the reactive oxygen species (ROS) generation and the loss of mitochondrial membrane potential (Δψm). ASI inhibited the mitochondrial permeability transition pore (mPTP) opening and activation of caspase-3, and finally decreased the cell apoptosis in cardiomyocytes. Furthermore, ASI upregulated Hes1 protein expression. However, pretreatment with DAPT, a Notch1 inhibitor, effectively attenuated the cardioprotective effects of ASI against A/R injury, except MDA, SOD, GSH-Px, and the ROS generation. Taken together, we demonstrated that ASI could protect against A/R injury via the Notch1/Hes1 signaling pathway.

Beneficial effects of astragaloside IV against angiotensin II-induced mitochondrial dysfunction in rat vascular smooth muscle cells

Angiotensin II (Ang II)-induced mitochondrial dysfunction is a prominent characteristic of the majority of cardiovascular diseases. Astragaloside IV (As-IV), the major active ingredient of Astragalus membranaceus (Fisch.) Bge. (a traditional Chinese herbal medicine), possesses antioxidant properties. The present study was carried out to examine whether As-IV can reverse Ang II-induced mitochondrial dysfunction in vascular smooth muscle cells (VSMCs) and to elucidate the underlying molecular mechanisms. Cultured rat aortic VSMCs treated with Ang II (1 µM) for 24 h exhibited mitochondrial dysfunction, including a decrease in mitochondrial oxygen consumption rates (OCRs), adenosine triphosphate (ATP) production and mitochondrial DNA (mtDNA) levels, as well as the disruption of mitochondrial structural integrity. Following treatment with Ang II, As-IV (50 µg/ml) was added to the culture medium followed by incubation for a further 24 h. The administration of As-IV significantly increased the mitochondrial OCRs, ATP production and the mtDNA levels, and reversed the mitochondrial morphological changes which occurred in the VSMCs. Treatment with As-IV also reversed the Ang II-induced increase in the production of reactive oxygen species (ROS), the increase in NADPH oxidase and xanthine oxidase activity, as well as the decrease in mitochondrial membrane potential (ΔΨm) and manganese superoxide dismutase (Mn-SOD) activity. Furthermore, treatment with As-IV led to an increase in the mRNA expression of peroxisome proliferator-activated receptor-gamma coactivator-1α (PGC-1α) and mitochondrial transcription factor A (Tfam), and in the protein expression of PGC-1α, parkin and dynamin 1-like protein 1 (Drp1) in the VSMCs. These results indicate that As-IV exerts beneficial effects on Ang II-induced mitochondrial dysfunction in rat VSMCs and that these effects are mediated through the inhibition of ROS overproduction, as well as the promotion of mitochondrial autophagy and mitochondrial biogenesis. These data demonstrate the antioxidant properties of As-IV.

Effects of treatment with Astragalus Membranaceus on function of rat leydig cells

BACKGROUND

Astragalus membranaceus (AM) is a Chinese traditional herb which has been reported to have broad positive effects on many diseases, including hepatitis, heart disease, diabetes and skin disease. AM can promote cell proliferation, increase the activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx), and inhibit apoptosis by regulating the transcription of proto-oncogenes controlling cell death. While AM is included in some commercially available "testosterone boosting supplements", studies directly testing ability of AM to modulate testosterone production are lacking. In the present study, we examined the effects of AM on Leydig cell function in vitro.

METHODS

Rat Leydig cells were purified and treated with AM at different concentrations (0 μg/mL, 10 μg/mL, 20 μg/mL, 50 μg/mL, 100 μg/mL and 150 μg/mL) and cell counting-8 (CCK-8) assay, Enzyme-linked immunosorbent assay, quantitative real time PCR and analysis of activities of SOD and GPx were done respectively.

RESULTS

Treatment with 100 μg/mL (P<0.05) and 150 μg/mL AM (P<0.01) significantly increased Leydig cell numbers. Treatment with AM (20 μg/mL, 50 μg/mL and 100 μg/mL) significantly increased testosterone production (P<0.01). In addition, increased Leydig cell SOD and GPx activities were observed in response to 20 μg/mL and 50 μg/mL AM treatment (P<0.01). Furthermore, expression of Bax mRNA was significantly decreased (P<0.01), and the ratio of Bcl-2/Bax mRNA was significantly increased in response to 20 μg/mL AM in the culture medium (P<0.05).

CONCLUSIONS

Results supported a beneficial effect of AM on multiple aspects of rat Leydig cell function in vitro including testosterone production.

Astragaloside effect on TGF-β1, SMAD2/3, and α-SMA expression in the kidney tissues of diabetic KKAy mice

Numerous cytokines participate in the occurrence and development of inflammation and renal interstitial fibrosis. Previous studies confirmed that TGF-β1 overexpressed in diabetic nephropathy. As a downstream signal protein of TGF-β1 family, SMAD has an important role in the process of α-SMA mediated renal interstitial fibrosis. This study aimed to study astragaloside effect on TGF-β1, SMAD2/3, and α-SMA expression in the kidney tissue of diabetic KKAy mice, to reveal its potential impact on renal interstitial fibrosis. 20 type II diabetic KKAy mice were randomly equally divided into model group and astragaloside group, while 10 male C57BL/6J mice were selected as the control. Astragaloside at 40 mg/(kg•d) was given when the KKAy mice fed with high-fat diet to 14 weeks old. The mice were killed at 24 weeks old and the kidney tissue samples were collected. Pathology morphological changes were observed. TGF-β1, SMAD2/3, and α-SMA expression levels were determined by immunohistochemistry. Compared with control, mice kidney in model group appeared obvious fibrosis and up-regulated blood glucose level, TGF-β1, SMAD2/3, and α-SMA expression (P < 0.05). Mice in astragaloside group exhibited alleviated renal interstitial fibrosis compared with the model. Its blood glucose level, TGF-β1, SMAD2/3, and α-SMA expression levels were significantly lower than the model group (P < 0.05). Astragaloside can delay the renal fibrosis process in diabetic mice by influencing the TGF-β/SMADS signaling pathway and down-regulating TGF-β1, SMAD2/3, and α-SMA expression.

Recent Advances in Traditional Chinese Medicine for Kidney Disease

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

Glycated albumin triggers fibrosis and apoptosis via an NADPH oxidase/Nox4-MAPK pathway-dependent mechanism in renal proximal tubular cells

Glycated albumin (GA), an Amadori product used as a marker of hyperglycemia and the early-stage glycation products compared to AGEs, might further promote kidney lesions in diabetic nephropathy (DN). However, the mechanisms how GA cause proximal tubular cells damage remain poorly understood. In this study, we investigated the effects of GA on fibrosis and apoptosis of renal proximal tubular cells (NRK-52E) in vitro experiments. Our results showed that GA promoted α-SMA, fibronectin (FN) and TGF-β expressions in NRK-52E cells. GA also increased cell apoptosis and stimulated the expressions of pro-caspase 3/cleaved-caspase 3. GA overloading enhanced the phosphorylation of MAPK pathway. GA-induced α-SMA, FN, TGF-β and caspase 3 expressions were completely suppressed by the NADPH oxidase inhibitor apocynin (Apo), the reactive oxygen species (ROS) scavenger N-acetylcysteine (NAC) and the latent antioxidant Astragaloside IV (AS-IV). Real-time PCR showed that GA increased Nox1, Nox2 and Nox4 mRNA expressions, especially the Nox4 expression. Furthermore, Nox4 siRNA blocked GA-induced tubular damages and the MAPK pathway activation. These results demonstrate that GA increases the permissiveness of proximal tubular cells to fibrosis and apoptosis in vitro by triggering a pathway that involves NADPH oxidase/Nox4-MAPK signaling pathway. This event may represent a key cellular effect in increasing the susceptibility of tubular cells to fibrosis and apoptosis when the tubules cope with a high GA load. This effect is instrumental to renal damage and disease progression in patients with DN.

Astragaloside IV ameliorates renal fibrosis via the inhibition of mitogen-activated protein kinases and antiapoptosis in vivo and in vitro

Apoptosis of renal tubular cells plays a crucial role in renal fibrosis. Astragaloside IV (AS-IV), a compound extracted from Radix Astragali, has been shown to inhibit renal tubular cell apoptosis induced by high glucose, but its role in preventing chronic renal fibrosis as well as the underlying molecular mechanisms involved still remain obscure. In this study, human kidney tubular epithelial cells induced by transforming growth factor-β1 (TGF-β1) were used to investigate the protective role of AS-IV in antifibrosis. As an in vivo model, mice subjected to unilateral ureteral obstruction (UUO) were administered AS-IV (20 mg/kg) by intraperitoneal injection for 7 days. AS-IV significantly alleviated renal mass loss and reduced the expression of α-smooth muscle actin, fibronectin, and collagen IV both in vitro and in vivo, suggesting that this compound functions in the inhibition of renal tubulointerstitial fibrosis. Furthermore, transferase-mediated dUTP nick-end labeling assay results both in vivo and in vitro showed that AS-IV significantly attenuated both UUO and TGF-β1-induced cell apoptosis and prevented renal tubular epithelial cell injury in a dose-dependent manner. Western blotting results also revealed that the antiapoptotic effect of AS-IV was reflected in the inhibition of caspase-3 activation, which might be mediated primarily by the downregulation of mitogen-activated protein kinase effectors phospho-p38 and phospho-c-Jun N-terminal kinase. These data infer that AS-IV effectively attenuates the progression of renal fibrosis after UUO injury and may have a promising clinical role as a potential antifibrosis treatment in patients with chronic kidney disease.

Effects of astragalus injection on the TGFβ/Smad pathway in the kidney in type 2 diabetic mice

Background

In traditional Chinese medicine, astragalus injection is used to treat diabetic nephropathy (DN). The current study was conducted to determine the effects of astragalus injection on DN by assessing potential modulation of the transforming growth factor beta TGFβ/Smad signaling pathway.

Methods

Diabetic, male KKAy mice, aged 14 weeks were randomly divided into a model group and an astragalus treatment group, while age-matched male C57BL/6J mice were selected as controls. The treatment group received daily intraperitoneal injections of astragalus (0.03 ml/10 g.d), while the model group received injections of an equivalent volume of saline. Mice were euthanized after 24 weeks. Serum samples were obtained from animals in each group, and blood glucose, creatinine, and urea nitrogen levels were measured. Tissue samples from the kidney were used for morphometric studies. The expression of TGFβ1, TGFβR-Ι, Smad3, and Smad7 were evaluated using reverse transcription-polymerase chain reaction (RT-PCR), and western blot analysis.

Results

Mice in the model group became obese, and suffered complications, including hyperglycemia, polyuria, and proteinuria. Astragalus treatment significantly reduced albuminuria, improved renal function, and ameliorated changes in renal histopathology. Moreover, administration of astragalus injection increased Smad7 expression, and inhibited the expression of TGFβR-Ι, Smad3 and its phosphorylation, and decreased the mRNA level of TGFβ1.

Conclusions

The TGFβ/Smad signaling pathway plays an important role in the development of DN. Administration of astragalus injection could prevent or mitigate DN by rebalancing TGFβ/Smad signaling, and could play a protective role in DN-induced renal damage in KKAy mice.

Beneficial effects of Astragaloside IV for hair loss via inhibition of Fas/Fas L-mediated apoptotic signaling

Apoptosis with premature termination of hair follicle growth induces several types of hair loss and is one of the crucial factors of hair loss. Astragaloside IV, which is a major component of Astragalus membranaceus, is a cycloartane triterpene saponin. Although an anti-apoptotic effect of Astragaloside IV has been reported, its effects against hair loss have not been investigated. To explore the underlying mechanisms of Astragaloside IV on apoptotic signaling in hair follicle, the dorsal skin of depilated C57BL/6 mice was topically treated with 1 and 100 μM Astragaloside IV for 14 days. In Astragaloside IV-treated group, TUNEL-positive cells were reduced. We found that Astragaloside IV blocked the procaspase-8, resulting in the inhibition of caspase-3 and procaspase-9 activities. The changes were accompanied with down-regulation of Bax and p53, and up-regulation of Bcl-2 and Bcl-_xL by Astragaloside IV treatment. In addition, activation of NF-κB and phosphorylation of IκB-α were inhibited, along with decreases in three MAPKs: ERK, SAPK/JNK and p38 by Astragaloside IV. The expressions of KGF, p21, TNF-α and IL-1β, which are keratinocyte terminal differentiation markers associated with catagen, were modulated by treatment with Astragaloside IV. These results demonstrated that Astragaloside IV is concerned with blocking the Fas/Fas L-mediated apoptotic pathway, which would be an alternative therapy for hair loss.

Astragaloside IV alleviates early brain injury following experimental subarachnoid hemorrhage in rats

Astragaloside IV, one of the main effective components isolated from Astragalus membranaceus, has multiple neuroprotective properties, while the effects of astragaloside IV on the attenuation of subarachnoid hemorrhage (SAH)-induced early brain injury (EBI) and its possible mechanisms are unknown. In the present study, we aimed to determine whether astragaloside IV could inhibit oxidative stress, reduce neuronal apoptosis, and improve neurological deficits after experimental SAH in rats. Rats (n=68) were randomly divided into the following groups: Sham group, SAH group, SAH+vehicle group, and SAH+astragaloside IV group. Astragaloside IV or an equal volume of vehicle was administered at 1 h and 6 h after SAH, all the rats were subsequently sacrificed at 24 h after SAH. Mortality, neurological scores, and brain edema were assessed, biochemical tests and histological studies were also performed at that point. SAH induced an increase in the malondialdehyde (MDA) level, neuronal apoptosis, cleaved caspase 3, brain edema and decreased activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). Astragaloside IV treatment reversed these changes and improved neurobehavioral outcomes of SAH rats. Our findings suggested that astragaloside IV may alleviate EBI after SAH through antioxidative and anti-apoptotic effects.