Protective Effect Of Astragaloside Research Articles

Total astragalosides decrease apoptosis and pyroptosis by inhibiting enterovirus 71 replication in gastric epithelial cells.

Enterovirus 71 (EV71) is one of the primary pathogens involved in severe hand, foot and mouth disease in children. EV71 infection causes various types of programmed cell death. However, there are currently no clinically approved specific antiviral drugs for control of EV71 infection. Astragalus membranaceus (AM), a Traditional Chinese medicine, has been used in antiviral therapy in China. The aim of the present study was to determine whether total astragalosides (ASTs), bioactive components of AM, protect against EV. DAPI nuclear staining was used to observe morphological changes of the nucleus and the protective effect of ASTs, which revealed that the nucleus shrank following EV71 infection, while ASTs reversed it. Cell Counting Kit-8 assay found that human normal gastric epithelial cell (GES-1 cell) viability decreased following EV71 infection, while lactate dehydrogenase (LDH) assay showed that EV71 infection induced GES-1 cell damage. Western blotting was used to measure the expression levels of apoptosis and pyroptosis marker protein to determine whether EV71 infection induced apoptosis and pyroptosis in GES-1 cells. Reverse transcription-quantitative PCR was used to determine the anti-EV71 effect of ASTs. The results showed that ASTs protected GES-1 cells from EV71-induced cell apoptosis and pyroptosis. Furthermore, the present data demonstrated that the protective effect of ASTs was exerted by suppressing EV71 replication and release. These findings suggested that ASTs may represent a potential antiviral agent for the treatment of EV71 infection.

Astragaloside IV Reduces OxLDL-Induced BNP Overexpression by Regulating HDAC.

Effective drug intervention is the most important method to improve the prognosis, improve the quality of life, and prolong the life of patients with heart failure. This study aimed to explore the protective effect of astragaloside IV on myocardial cell injury induced by oxidized low-density lipoprotein (OxLDL) and its regulatory mechanism on the increase of brain natriuretic peptide (BNP) caused by myocardial cell injury. The model of myocardial cell injury, protection, and histone deacetylase (HDAC) inhibition in HL-1 mice was established by OxLDL treatment, astragaloside IV intervention, and UF010 coincubation. The effects of OxLDL and astragaloside IV on apoptosis were detected by flow cytometry. The expression level of BNP mRNA and protein in cells was investigated by real-time fluorescence quantification, western blot, and enzyme-linked immunosorbent assay. HDAC activity in nucleus was calibrated by fluorescence absorption intensity. Enzyme-linked immunosorbent assay (ELISA) was applied to test eNOS level in myocardial cells. OxLDL significantly promoted apoptosis, upregulated BNP mRNA, increased BNP protein level inside and outside cells, and decreased eNOS level. Compared with OxLDL treatment group, apoptosis decreased, BNP mRNA expression level decreased, BNP protein concentration decreased, and eNOS level increased significantly combined with low and high concentration astragaloside IV treatment group. HDAC activity significantly increased in OxLDL treatment group and significantly decreased after combined incubation with low and high concentrations of astragaloside IV. Inhibition of HDAC significantly increased eNOS level and decreased BNP protein level. In conclusion, astragaloside IV can reverse the low level of eNOS caused by OxLDL by regulating HDAC activity to protect myocardial cells from oxide damage, which is manifested by the decrease of BNP concentration.

Protective effect of astragaloside IV on cadmium-induced spermatogenesis microenvironment damage in rats

ABSTRACT The previous study using Sertoli cells cultured in vitro has shown that the protective effects of astragaloside IV (AsIV) on cadmium (Cd)-induced damage to Sertoli cells and its membrane proteins. Yet, it is not known if AsIV has an equivalent effect on Cd-induced damage to the spermatogenesis microenvironment in rats. Using an in vivo model, Cd-induced damage to the spermatogenesis microenvironment and the protective effects of AsIV were studied. Eighteen male Sprague Dawley (SD) rats were randomly divided into three groups (n = 6/group): Cd group, Cd&AsIV group, and control group. Cd was administered to the rats in the Cd group via i.p. at 1 mg/kg body weight once daily, Cd and AsIV was administered to the rats in the Cd&AsIV group via i.p. at 1 mg/kg body weight and 10 mg/kg body weight respectively once daily, and the same volume of saline was administered to the rats in control group via i.p. once daily. The rats in the three groups were injected continuously for 5 days. Vesicular formation in the seminiferous tubules was observed in the Cd treatment group. The average optical density of claudin-11, zonal occludin-1 (ZO-1), and connexin 43 (Cx43) decreased significantly in the Cd treatment group. The ultrastructural damage of the Sertoli cells and tight junctions were also observed by electron microscopy. AsIV treatment rescued the morphologic changes of the seminiferous tubules of the testis and the ultrastructural damage of the Sertoli cells and tight junctions. The average optical density of claudin-11, ZO-1, and Cx43 also increased significantly after AsIV treatment. Cd damages the spermatogenesis microenvironment in rats, which can be rescued by AsIV treatment. These results illustrate that AsIV may also have a protective effect on Cd-induced damage to the spermatogenesis microenvironment in rats. Abbreviations: AsIV: astragaloside IV; Cd: cadmium; SD: Sprague Dawley; ZO-1: zonal occludin-1; Cx43: connexin 43; BTB: blood-testis barrier; MAPKs: mitogen-activated protein kinases; OSP: oligodendrocyte-specific protein; Cxs: connexins; GJIC: gap junctional intercellular communication; ROS: reactive oxygenspecies; MDA: malondialdehyde; TGF: tumor growth factor; PBS: phosphate buffersaline; BSA: bovine serum albumin

Astragaloside suppresses tumor necrosis factor receptor-associated factor 5 signaling pathway and alleviates neurodegenerative changes in retinal pigment epithelial cells induced by isoflurane.

Epidemiological studies showed that isoflurane, a general anesthetic widely used in surgery including those for the children, is associated with impairment of neurodevelopment and neurodegenerative diseases, such as Alzheimer's disease (AD) and age-related macular degeneration (AMD), which are related to the accumulation of reactive oxygen species (ROS). Astragaloside (AS) is an antioxidant derivative from a traditional Chinese herbal medicine Astragalus membraneaceus Bunge. In this study, we used retinal pigment epithelial cells, which share plenty of features with neurodegenerative diseases such as AD and AMD to investigate the effect of AS. Cell cycle re-entry and proapoptosis were seen in retinal pigment epithelium (RPE) cells treated with isoflurane, which was alleviated by pretreatment of AS. Further, tumor necrosis factor receptor-associated factor 5 (TRAF5) and downstream nuclear factor-κB (NF-κB) were investigated to elucidate the molecular mechanism underlying protective effect of AS. RPE cells exposed to isoflurane expressed higher TRAF5 and NF-κB than those pretreated with AS, suggesting a critical role of TRAF5 therein. In Morris water maze (MWM) assay, Sprague-Dawley rats pretreated with AS and then exposed to isoflurane spent less time in swimming to the platform, and their TRAF5 expression was significantly lower than those received anesthesia alone. Further studies on the consequence of forced downregulation or upregulation are warranted that may employ cutting-edge technologies such as optogenetics to overcome the difficulties in manipulating expression of TRAF5. Although the link between TRAF5 and neurodegeneration requires more in-depth investigations, our study provide a novel hint on the pathological mechanism of isoflurane and suggest a potential target for eliminating persistent side effect of anesthesia.

Protective effect of Astragaloside IV on the oxygenation induced by RAW264.7 murine macrophage

Objective To investigate the protective effect and mechanism of Astragaloside Ⅳ (AS-Ⅳ) on hypoxia/re-oxygenation induced by RAW264.7 murine macrophages. Methods The hypoxia/re- oxygenation induced RAW264.7 murine macrophages served as a model of I/R injury. The cells were divided into the control group, the model group, and the AS-Ⅳ group. The cell morphological changes of each group were observed directly under inverted microscope. Inducible nitric oxide synthase (iNOS), cluster of differentiation 206 (CD206), and peroxisome proliferator activated receptor- γ (PPAR-γ) were separately examined by RT-PCR, Western blot analysis and immunofluorescence staining. Results Compared with the model group, the numbers of cell in AS-Ⅳ group significantly increased , and the cell physiological status were much better. Compared with the model group, the iNOS immunofluorescence semi quantitative (0.62 ± 0.02 vs. 1.32 ± 0.09), the expression of mRNA (1.51 ± 0.07 vs. 3.46 ± 0.39), and protein (2.30 ± 0.14 vs. 5.16 ± 0.49) significantly reduced in AS-Ⅳ group (P<0.01). The CD206 immunofluorescence semi quantitative (1.01 ± 0.03 vs. 0.61 ± 0.01), the expression of mRNA (0.91 ± 0.03 vs. 0.51 ± 0.01), and protein (0.61 ± 0.04 vs. 0.19 ± 0.01) significantly reduced in AS-Ⅳ group (P<0.01). Compared with the model group, the PPAR-γ immunofluorescence semi quantitative (0.60 ± 0.14 vs. 0.34 ± 0.03), mRNA (2.00 ± 0.14 vs. 1.04 ± 0.03), and protein (0.67 ± 0.05 vs. 0.19 ± 0.01) significantly increased (P<0.01). Conclusions The AS-Ⅳ could attenuate ischemia-reperfusion injury by altering macrophages phenotype through upregulation PPAR-γ. Key words: Astragaloside Ⅳ; Reperfusion injury; Macrophages; PPAR gamma

Protective effects of astragaloside in rats with adriamycin nephropathy and underlying mechanism

The present study was designed to determine the mechanism underlying the treatment of nephrotic syndrome using astragaloside by observing the effects of astragaloside on the expression of nephrin and podocin proteins and genes in kidneys of rats with adriamycin nephropathy. The rats were injected with adriamycin and, after successful model establishment, randomly divided into a model group, a Methylprednisolone (MP) group, and an astragaloside group. The 24-h complete urine samples were collected. Biochemical indicators were monitored, and kidney tissues were collected for pathological analysis using light microscopy and electron microscopy. The mRNA expression of nephrin and podocin was measured in the kidney tissues using the real-time qPCR, and the protein expression levels of nephrin and podocin were detected using Western blot analysis. At the end of 12 weeks of drug intervention, the urinary protein level was lower in the MP and astragaloside groups than that in the model group (P = 0.008 and P = 0.01, respectively). Serum albumin was higher in the MP and astragaloside groups than in the model group (P < 0.001 and P = 0.012, respectively). Podocytes in the MP group were nearly normal, and fusion of podocytes in the astragaloside group was significantly less than that in the control group. The nephrin and podocin mRNA and protein expression levels in the intervention groups were higher (P < 0.05) than that in the model group. Due to the increased expression of podocyte-related nephrin and podocin proteins, astragaloside maintained slit diaphragm integrity and decreased the level of proteinuria in rats with adriamycin nephropathy.

Experimental study on hplc determination of astragaloside in qishen huoxue granule and its protective effect in septic rats

Objective: To determine the astragaloside content in Qishen Huoxue Granule (QHG) by HPLC and to investigate the protective effect of astragaloside in septic rats. Methods: Dikma Diamonsil TM C 18 column was used. Mobile phase was methanol: acetonitrile (42:58) and detection was performed at 205 nm. Healthy rats were randomly divided into three groups, group A: sham operation (SO) group; group B: cecal ligation and puncture (CLP) group; and group C: CLP QHG treatment group. 72 h after model establishment, plasma tumor necrosis factor-α (TNF-α), plasma and peritoneal albumin concentrations, as well as mesenteric venular flow velocity in each group were measured and degree of intestinal mucosal injury was observed. Results: Average recovery was 100.7%, with a RSD of 2.20%. Sample concentration exhibited good linearity with peak area within a 0.01~0.2 mg/mL range. After CLP, plasma TNF-α concentration and albumin leakage in rats increased markedly; such increases were more significant in group B than group C (P<0.01). Changes in intestinal mucosal scores also presented the same trend (P<0.01). Mesenteric venular flow slowed down and plasma albumin concentration lowered; such decreases were more significant in group B than group C (P<0.05). Conclusion: QHG can reduce the inflammatory response and intestinal mucosal injury in rats with CLP-induced sepsis.

Protective effect of astragaloside IV against ultraviolet B-induced photodamage to human HaCaT keratinocytes and its mechanisms

Objective To evaluate the protective effect of astragaloside Ⅳ against ultraviolet B (UVB)-induced photodamage to human HaCaT keratinocytes,and to investigate its mechanisms.Methods Culturedimmortalized human HaCaT keratinocytes were divided into four groups:blank control group receiving untreated,UVB group irradiated with 50 mJ/cm2 UVB,astragaloside Ⅳ group treated with astragaloside Ⅳ,UVB + astragalosideⅣ group treated with astragaloside Ⅳ for 24 hours before and after 50 mJ/cm2 of UVB radiation.The concentration ofastragaloside Ⅳ ranged from 10 to 200 mg/L in cell proliferation assay,and according to the results of proliferationassay,20 mg/L was determined as the optimal concentration in the other assays.At 24 hours after UVB radiation,cellcounting kit-8 (CCK8) assay was performed to evaluate cellular proliferative activity,flow cytometry to determineintracellular reactive oxygen species (ROS) levels,and Western blot to measure the expression levels of p53,p38,matrix metalloproteinase-9 (MMP-9) and high mobility group Al (HMGA-1) protein in HaCaT cells.ResultsCompared with the control group,astragaloside Ⅳ at 10 and 20 mg/L had no inhibitory effect (F =1.32,P ＞ 0.05),while astragaloside Ⅳ at 50,100 and 200 mg/L showed significantly inhibitory effect (F =20.20,P ＜ 0.05),on theproliferation of HaCaT cells.In addition,cellular proliferative activity in the UVB group was significantly lower thanthat in the control group (F =99.00,P ＜ 0.01).Compared with the UVB group,cellular proliferative activityincreased to different degrees in HaCaT cells treated with both UVB and astragaloside Ⅳ of 10-200 mg/L (F =19.08,P ＜ 0.01),with the strongest increase observed in those treated with UVB and astragaloside Ⅳ of 20 mg/L.Further experiments revealed reduced intracellular ROS levels in the UVB + astragaloside Ⅳ (20 mg/L) groupcompared with the UVB group (t =21.12,P ＜ 0.01).Western blot assay showed that the expression levels of p53,p38,MMP-9 and HMGA-1 protein were significantly higher in the UVB group than in the control group (all P ＜0.01),but significantly lower in the UVB + astragaloside Ⅳ (20 mg/L) group than in the UVB group (all P ＜ 0.01).Conclusion Astragaloside Ⅳ can effectively protect keratinocytes from UVB-induced photodamage. Key words: Astragalus membranaceus; Ultraviolet rays; Keratinocytes; Reactive oxygen species

Astragaloside IV Protects against Cardiac Hypertrophy via Inhibiting the Ca2+/CaN Signaling Pathway

Astragaloside IV is widely used for the treatment of cardiovascular diseases in China. However, its role in cardiac hypertrophy remains unclear. In this study, we aim to determine the protective effects of astragaloside IV on myocardial hypertrophy induced by lipopolysaccharide and to identify their precise molecular and cellular mechanisms. Cell size, reorganization of actin filaments, and ANP and BNP mRNA expression were used as indices of hypertrophy; CaN and GATA-4 expression and the distribution of NFAT-3 in both cytoplasm and nucleus were determined by Western blot analysis; Ca2+ transient in Fura-2/AM-loaded cells was measured by Till image system. Our data demonstrated that lipopolysaccharide challenge induced cardiac hypertrophy, increased resting Ca2+ transient level, promoted activation of CaN and GATA-4, and enhanced nuclear translocation of NFAT-3. Administration of astragaloside IV (16, 32, and 64 µM) 1 h prior to lipopolysaccharide stimulation dose-dependently attenuated cardiac hypertrophy induced by lipopolysaccharide. Further studies demonstrated that astragaloside IV inhibited the increment of the resting intracellular free Ca2+, and its effect was similar to verapamil. Moreover, astragaloside IV also inhibited the activation of CaN and GATA-4, and the nuclear translocation of NFAT-3 induced by lipopolysaccharide. In conclusion, our results revealed that astragaloside IV had the potential to protect against cardiac hypertrophy through Ca2+-mediated CaN signaling pathways.

Protective effects of astragaloside IV on high-glucose-induced damage of retinal ganglion cells

To explore the protective effects of astragaloside IV on retinal ganglion cells (RGC) incubated under high glucose. Cultured RGC-5 were divided into 3 groups: control, high glucose and high glucose+astragaloside IV. The survival rate of cell was measured by CCK-8 kit and flow cytometry. The changes of mitochondrial membrane potential were monitored by confocal laser scanning microscopy while those of RGC-5 mitochondria observed by electron microscopy. When the cell survival rate was 100% in the control group, the survival rate improved after 1 h 5, 10, 50, 100, 200 µg/ml astragaloside IV pretreatment and high-glucose culture. The cell survival rates for 100 mg/L, 200 mg/L of astragaloside IV were 81.6%, 80.0%, the difference from the high glucose group (66%) was significant (P < 0.05) and 100 mg/L of astragaloside IV was the best protection concentration. The apoptotic rate for 100 mg/L astragaloside IV pretreated group of RGC-5 cell was 6.1%. And it could partially inhibit the RGC-5 cell apoptosis caused by high glucose (8.2%) (P < 0.05). In the high-glucose group, the cells showed marked increases in mitochondrial swelling, especially for cristae. Numerous normal mitochondria were observed in 100 mg/L astragaloside IV pretreated group. Astragaloside IV could elevate mitochondrial membrane potential and alleviate mitochondrial swelling. Astragaloside IV can protect RGC from high-glucose induced damage and may benefit the patients with diabetic retinopathy.

Protective Effect of Astragalosides on Myocardial Injury by Isoproterenol in SD Rats

We have extracted and roughly purified astragalosides (AS) from Astragalus membranaceus, a natural herb used as a traditional Chinese medicine, regarded to have pharmacodynamic benefits of protecting injured myocardium. We hypothesized that the astragalosides might exert beneficial effect in myocardial lesion by preserving both energy metabolism and Ca(2+) homeostasis. Sprague-Dauley (SD) rats were injected with isoproterenol (ISO) subcutaneous (s.c.) at a dose of 5 mg/kg/day consecutively for two days as models and were treated with astragalosides and trimetazidine intraperitoneally (i.p.) respectively, at a dose of 5 mg/kg/day one day prior to isoproterenol for 8 days. The histological changes were alleviated in isoproterenol-injected SD rats treated with astragalosides. Compared with isoproterenol-injected rats, the concentration of myocardial intracellular [Ca(2+)]i was decreased, L-type Ca(2+) current density and sarcoplasmic reticulum (SR) Ca(2+) load were recovered, the concentration of myocardial ATP was increased and phosphocreatine (PCr) was decreased in rats treated with astragalosides. In conclusion, the efficacious treatment of astragalosides for myocardial injury might be through regulating intracellular Ca(2+) homeostasis and energy metabolism.