Astragaloside IV inhibits PMA-induced EPCR shedding through MAPKs and PKC pathway

Astragaloside IV protects against oxidized low-density lipoprotein-induced injury in human umbilical vein endothelial cells via the histone deacetylase 9 (HDAC9)/NF-κB axis

BACKGROUND

Atherosclerosis is a main cause of multiple cardiovascular diseases, and cell damage of human umbilical vein endothelial cells (HUVECs) was reported to participate in the development of atherosclerosis. In this study, we aimed to study the action of Astragaloside IV (ASV) on AS development using in vitro AS cell model.

METHODS

MTT assay, EdU staining assay, and flow cytometry were utilized for detection of cell proliferation and apoptosis, respectively. The protein expression of histone deacetylase 9 (HDAC9), Bax, Bcl-2, p-P65, P65, p-IκBα, and IκBα was gaged using western blot. The angiogenesis was evaluated by tube formation assay. The inflammatory response was evaluated by ELISA kits. SOD activity and MDA level were detected using the matched commercial kits. RT-qPCR was used for HDAC9 mRNA expression measurement.

RESULTS

Oxidized low-density lipoprotein (ox-LDL) significantly repressed cell proliferation, angiogenesis, and enhanced apoptosis, inflammation, and oxidative stress in HUVECs. ASV addition could alleviate ox-LDL-caused cell damage in HUVECs. Moreover, HDAC9 was overexpressed in AS patients and AS cell model. Functionally, HDAC9 knockdown also exhibited the protective role in ox-LDL-treated HUVECs. In addition, ASV treatment protected against ox-LDL-induced damage in HUVECs via targeting HDAC9. ASV could inactivate the NF-κB pathway via regulating HDAC9 in AS cell model.

CONCLUSION

ASV exerted the protective effects on ox-LDL-induced damage in HUVECs through the HDAC9/NF-κB axis.

Astragaloside IV alleviates atherosclerosis through targeting circ_0000231/miR-135a-5p/CLIC4 axis in AS cell model in vitro

Non-coding RNAs (ncRNAs) have shown to act as crucial mediators in atherosclerosis (AS) development. The purpose of our study was to explore the role of Astragaloside IV (ASV) and circular RNA_0000231 (circ_0000231) in AS using AS cell model. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry were used to analyze cell viability and apoptosis. Migration ability was assessed by transwell migration assay and wound healing assay. The inflammatory response was evaluated via enzyme-linked immunosorbent assay (ELISA). Oxidative status was assessed via matching commercial kits. Western blot assay was conducted to detect the expression of monocyte chemoattractant protein 1 (MCP1), intercellular adhesion molecule 1 (ICAM1), and chloride intracellular channel 4 (CLIC4). The levels of circ_0000231, its linear form Rho GTPase activating protein 12 (ARHGAP12), microRNA-135a-5p (miR-135a-5p), and CLIC4 messenger RNA (mRNA) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Circ_0000231-miRNA interactions were established using Starbase and Circbank softwares, while the targets of miR-135a-5p were explored by Starbase software. Dual-luciferase reporter assay and RNA-pull down assay were used to verify these target interactions. ASV suppressed the apoptosis, inflammation, and oxidative stress while recovered the viability and migration ability of HUVECs which were mediated by oxidized low-density lipoprotein (ox-LDL). Circ_0000231 overexpression antagonized the protective role of ASV in ox-LDL-induced HUVECs. MiR-135a-5p was verified as a direct target of circ_0000231, and circ_0000231 contributed to ox-LDL-induced cell injury of HUVECs through down-regulating miR-135a-5p. MiR-135a-5p directly interacted with the 3' untranslated region (3'-UTR) of CLIC4 mRNA in HUVECs, and miR-135a-5p protected HUVECs against ox-LDL-induced injury through down-regulating CLIC4. ASV protected HUVECs against ox-LDL-induced injury through targeting circ_0000231/miR-135a-5p/CLIC4 axis. Targeting circ_0000231/miR-135a-5p/CLIC4 axis might provide a novel insight to develop effective strategy for AS treatment.

Potential mechanisms of Chinese Herbal Medicine that implicated in the treatment of COVID-19 related renal injury

Clinical studies have shown that renal injury in Corona Virus Disease 2019 (COVID-19) patients has been a real concern, which is associated with high mortality and an inflammation/apoptosis-related causality. Effective target therapy for renal injury has yet been developed. Besides, potential anti-COVID-19 medicines have also been reported to cause adverse side effects to kidney. Chinese Herbal Medicine (CHM), however, has rich experience in treating renal injury and has successfully applied in China in the battle of COVID-19. Nevertheless, the molecular mechanisms of CHM treatment are still unclear. In this study, we searched prescriptions in the treatment of renal injury extensively and the potential mechanisms to treat COVID-19 related renal injury were investigated. The association rules analysis showed that the core herbs includes Huang Qi, Fu Ling, Bai Zhu, Di Huang, Shan Yao. TCM herbs regulate core pathways, such as AGE-RAGE, PI3K-AKT, TNF and apoptosis pathway, etc. The ingredients (quercetin, formononetin, kaempferol, etc.,) from core herbs could modulate targets (PTGS2 (COX2), PTGS1 (COX1), IL6, CASP3, NOS2, and TNF, etc.), and thereby prevent the pharmacological and non-pharmacological renal injury comparable to that from COVID-19 infection. This study provides therapeutic potentials of CHM to combat COVID-19 related renal injury to reduce complications and mortality.

Astragaloside IV inhibits oxidized low‑density lipoprotein‑induced endothelial damage via upregulation of miR‑140‑3p

Oxidized low‑density lipoprotein (ox‑LDL)‑mediated endothelial cell injury has an important role in the vascular complications of type 2 diabetes. Astragaloside IV (ASV) is an active component of Radix Astragali, which has been demonstrated to exert protective effects against endothelial damage. The present study explored whether microRNAs (miRNAs) are involved in mediating the protective effects of ASV on ox‑LDL‑induced damage in human umbilical vein endothelial cells (HUVECs). RNA sequencing and reverse transcription‑quantitative PCR analyses revealed that ox‑LDL treatment significantly downregulated miR‑140‑3p expression in HUVECs. miR‑140‑3p overexpression promoted cell proliferation and inhibited apoptosis in ox‑LDL‑induced HUVECs. However, inhibition of miR‑140‑3p expression could reverse the effects of ASV on ox‑LDL‑induced HUVECs and reactivate ASV‑inhibited PI3K/Akt signaling in ox‑LDL‑induced HUVECs. In addition, Krüppel‑like factor 4 (KLF4) was identified as a target of miR‑140‑3p in ox‑LDL‑treated HUVECs. Subsequent experiments revealed that KLF4 overexpression partially counteracted the protective effects of miR‑140‑3p or ASV treatment in ox‑LDL‑induced HUVECs. Taken together, the current findings demonstrated that the protective effects of ASV on HUVECs were dependent on miR‑140‑3p upregulation and subsequent inhibition of KLF4 expression, which in turn suppressed the PI3K/Akt signaling pathway. The present results shed light to the molecular mechanism by which ASV alleviated ox‑LDL‑induced endothelial cell damage.

Astragaloside IV enhances taxol chemosensitivity of breast cancer via caveolin-1-targeting oxidant damage

Accumulating evidence suggests that caveolin-1 (CAV-1) is a stress-related oncotarget and closely correlated to chemoresistance. Targeting CAV-1 might be a promising strategy to improve chemosensitivity for breast cancer treatment. Astragaloside IV (AS-IV), a bioactive compound purified from Astragalus membranaceus, has been shown to exhibit multiple bioactivities, including anticancer. However, the involved molecular targets are still ambiguous. In this study, we investigated the critical role of CAV-1 in mediating the chemosensitizing effects of AS-IV to Taxol on breast cancer. We found that AS-IV could enhance the chemosensitivity of Taxol with minimal direct cytotoxicity on breast cancer cell lines MCF-7 and MDA-MB-231, as well as the nontumor mammary epithelial cell line MCF-10A. AS-IV was further demonstrated to aggravate Taxol-induced apoptosis and G2/M checkpoint arrest. The phosphorylation of mitogen-activated protein kinase (MAPK) signaling extracellular signal-regulated kinase (ERK) and c-Jun N-terminal Kinase (JNK), except p38, was also abrogated by a synergistic interaction between AS-IV and Taxol. Moreover, AS-IV inhibited CAV-1 expression in a dose-dependent manner and reversed CAV-1 upregulation induced by Taxol administration. Mechanism study further demonstrated that AS-IV treatment triggered the eNOS/NO/ONOO^- pathway via inhibiting CAV-1, which led to intense oxidant damage. CAV-1 overexpression abolished the chemosensitizing effects of AS-IV to Taxol by inhibiting oxidative stress. In vivo experiments further validated that AS-IV increased Taxol chemosensitivity on breast cancer via inhibiting CAV-1 expression, followed by activation of the eNOS/NO/ONOO^- pathway. Taken together, our findings not only suggested the potential of AS-IV as a promising candidate to enhance chemosensitivity, but also highlighted the significance of CAV-1 as the target to reverse cancer drug resistance.