Astragaloside IV protects cardiomyocytes from hypoxic injury by regulating endoplasmic reticulum stress via eIF2α/CHOP signaling pathway.

Endoplasmic reticulum stress (ER stress) is suggested to promote cardiomyocyte apoptosis and ultimately lead to ischemic injury. Inhibition of ER stress-induced apoptosis may be a therapeutic strategy for MI injury. Astragaloside-IV (AST) from Astragalus membranaceus (Fisch) Bge, was reported to have cardioprotective properties. In this study, we investigated the protective effect of AST on cardiomyocytes against hypoxia injury by regulating ER stress and inhibiting apoptosis. H9c2 cardiomyocytes were divided into three groups, normal group, hypoxia group and AST group. Cell viability was determined by CCK-8 assay. Intracellular reactive oxygen species (ROS) production was detected by DCFH-DA (2,7- dichloro-dihydrofluorescein diacetate) florescent staining. The study showed that AST treatment could significantly increase the cell viability of H9c2 cells exposed to hypoxia. Furthermore, AST could restrain cell apoptosis and decrease the production of ROS. Compared with normal group, the protein levels of Bax, caspase-3, caspase-9, GRP78, p-eIF2α, and CHOP were enhanced in the hypoxia group, whereas the protein level of Bcl-2 was dramatically reduced. Compared with hypoxia group, AST markedly inhibited the phosphorylation of eIF2α and the expression of caspase-3, caspase-9 and CHOP, and promoted the protein expression of Bcl-2. Thus, AST can inhibit the ER stress-mediated apoptosis, partly through the eIF2α/CHOP pathway suppression to inhibit ER stress.

MiR-199a-5p enhances neuronal differentiation of neural stem cells and promotes neurogenesis by targeting Cav-1 after cerebral ischemia.

AIMS: MicroRNAs (miRs) are involved in endogenous neurogenesis, enhancing of which has been regarded as a potential therapeutic strategy for ischemic stroke treatment; however, whether miR-199a-5p mediates postischemic neurogenesis remains unclear. This study aims to investigate the proneurogenesis effects of miR-199a-5p and its possible mechanism after ischemic stroke. METHODS: Neural stem cells (NSCs) were transfected using Lipofectamine 3000 reagent, and the differentiation of NSCs was evaluated by immunofluorescence and Western blotting. Dual-luciferase reporter assay was performed to verify the target gene of miR-199a-5p. MiR-199a-5p agomir/antagomir were injected intracerebroventricularly. The sensorimotor functions were evaluated by neurobehavioral tests, infarct volume was measured by toluidine blue staining, neurogenesis was detected by immunofluorescence assay, and the protein levels of neuronal nuclei (NeuN), glial fibrillary acidic protein (GFAP), caveolin-1 (Cav-1), vascular endothelial growth factor (VEGF), and brain-derived neurotrophic factor (BDNF) were measured by Western blotting. RESULTS: MiR-199a-5p mimic enhanced neuronal differentiation and inhibited astrocyte differentiation of NSCs, while a miR-199a-5p inhibitor induced the opposite effects, which can be reversed by Cav-1 siRNA. Cav-1 was through the dual-luciferase reporter assay confirmed as a target gene of miR-199a-5p. miR-199a-5p agomir in rat stroke models manifested multiple benefits, such as improving neurological deficits, reducing infarct volume, promoting neurogenesis, inhibiting Cav-1, and increasing VEGF and BDNF, which was reversed by the miR-199a-5p antagomir. CONCLUSION: MiR-199a-5p may target and inhibit Cav-1 to enhance neurogenesis and thus promote functional recovery after cerebral ischemia. These findings indicate that miR-199a-5p is a promising target for the treatment of ischemic stroke.

A Preliminary Study on the Relationship Between High-Resolution Computed Tomography and Pulmonary Function in People at Risk of Developing Chronic Obstructive Pulmonary Disease.

Objectives: Patients with chronic obstructive pulmonary disease (COPD) have high morbidity and mortality, the opportunity to carry out a thoracic high-resolution CT (HRCT) scan may increase the possibility to identify the group at risk of disease. The aim of our study was to explore the differences in HRCT emphysema parameters, air trapping parameters, and lung density parameters between high and low-risk patients of COPD and evaluate their correlation with pulmonary function parameters. Methods: In this retrospective, single-center cohort study, we enrolled outpatients from the Physical Examination Center and Respiratory Medicine of The First Affiliated Hospital of Wenzhou Medical University. The patients who were ≥ 40 years-old, had chronic cough or sputum production, and/or had exposure to risk factors for the disease and had not reached the diagnostic criteria is considered people at risk of COPD. They were divided into low-risk group and high-risk group according to FEV1/FVC ≥ 80% and 80%>FEV1/FVC ≥ 70%. Data on clinical characteristics, clinical symptom score, pulmonary function, and HRCT were recorded. Results: 72 COPD high-risk patients and 86 COPD low-risk patients were enrolled in the study, and the air trapping index of left, right, and bilateral lungs of the high-risk group were higher than those of the low-risk group. However, the result of mean expiratory lung density was opposite. The emphysema index of left, right, and bilateral lungs were negatively correlated with FEV1/FVC (correlation coefficients were -0.33, -0.22, -0.26). Consistently, the air trapping index of left and right lungs and bilateral lungs were negatively correlated with FEV1/FVC (correlation coefficients were -0.33, -0.23, -0.28). Additionally, the mean expiratory lung density of left and right lungs and bilateral lungs were positively correlated with FEV1/FVC (correlation coefficients were 0.31, 0.25, 0.29). Conclusion: The emphysema index, air trapping index and the mean expiratory lung density shows significantly positive correlation with FEV1/FVC which can be used to assess the pulmonary function status of people at risk of COPD and provide a useful supplement for the early and comprehensive assessment of the disease.

Astragaloside IV promotes microglia/macrophages M2 polarization and enhances neurogenesis and angiogenesis through PPARγ pathway after cerebral ischemia/reperfusion injury in rats.

Microglia/macrophages play a dual role in brain injury and repair following cerebral ischemia/reperfusion. Promoting microglia/macrophage polarization from pro-inflammatory M1 to anti-inflammatory M2 phenotype has been considered as a potential treatment for ischemic stroke. Astragaloside IV (AS-IV) is a primary active ingredient of Chinese herb Radix Astragali, which protects against acute cerebral ischemic/reperfusion injury through its antioxidant, anti-inflammatory, and anti-apoptotic properties. However, it remains unknown whether AS-IV improves ischemic brain tissue repair and its underlying mechanism. A transient middle cerebral artery occlusion (tMCAO) rat model was used in this study. The results showed that AS-IV significantly improved long-term brain injury, reduced the expression of M1 microglia/macrophage markers and increased the expression of M2 microglia/macrophage markers 14 days after cerebral ischemia/reperfusion. AS-IV also increased peroxisome proliferator-activated receptor γ (PPARγ) mRNA and protein expression. Moreover, AS-IV promoted neurogenesis and angiogenesis, and increased the protein expression of brain-derived growth factor (BDNF), insulin-like growth factor-1 (IGF-1) and vascular endothelial growth factor (VEGF). However, these beneficial effects were greatly blocked by PPARγ antagonist T0070907. These results together suggest that AS-IV could enhance neurogenesis, angiogenesis and neurological functional recovery, which may be partially through transforming microglia/macrophage from M1 to M2 phenotype in a PPARγ-dependent manner after cerebral ischemia/reperfusion injury. Therefore, AS-IV can be considered as a promising therapeutic agent for ischemic stroke.

[Chinese medicine Buyang Huanwu decoction promotes neurogenesis and angiogenesis in ischemic stroke rats by upregulating miR-199a-5p expression].

OBJECTIVE: To investigate the mechanism of Chinese medicine Buyang Huanwu decoction (BYHWD) promoting neurogenesis and angiogenesis in ischemic stroke rats. METHODS: Male SD rats were randomly divided into sham operation group, model group, BYHWD group, antagonist group and antagonist control group with 14 rats in each. Focal cerebral ischemia was induced by occlusion of the right middle cerebral artery for 90 min with intraluminal filament and reperfusion for 14 d in all groups except sham operation group. BYHWD (13 g/kg) was administrated by gastrogavage in BYHWD group, antagonist group and antagonist control group at 24 h after modeling respectively, and BrdU (50 mg/kg) was injected intraperitoneally in all groups once a day for 14 consecutive days. miR-199a-5p antagomir or NC (10 nmol) was injected into the lateral ventricle at d5 after ischemia in antagonist and antagonist control groups, respectively. The neurological deficits were evaluated by the modified neurological severity score (mNSS) and the corner test, and the infract volume was measured by toluidine blue staining. Neurogenesis and angiogenesis were detected by immunofluorescence double labeling method. The expression level of miR-199a-5p was tested by real-time RT-PCR, and the protein expressions of vascular endothelial growth factor (VEGF) and brain-derived neurotrophic factor (BDNF) were determined by Western blotting. RESULTS: BYHWD treatment significantly promoted the recovery of neurological function (P<0.05 or P<0.01), reduced the infarct volume (P<0.05), increased the number of BrdU+/DCX+, BrdU+/NeuN+ and BrdU+/vWF+ cells (all P<0.01), upregulated the expression of miR-199a-5p (P<0.01), and increased the protein expression of VEGF and BDNF at d14 after cerebral ischemia (all P<0.05). The above effects were reversed by intracerebroventricular injection of miR-199a-5p antagomir. CONCLUSIONS: Buyang Huanwu decoction promotes neurogenesis and angiogenesis in rats with cerebral ischemia, which may be related to increased protein expression of VEGF and BDNF through upregulating miR-199a-5p.

Lianhua Qingwen prescription for Coronavirus disease 2019 (COVID-19) treatment: Advances and prospects.

BACKGROUND: An outbreak of Coronavirus Disease 2019 (COVID-19) which was infected by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), is still spreading and has led to unprecedented health emergency over the world. Though no specific drug has been developed so far, emerging agents have been confirmed effective or potentially beneficial to restrain it. Lianhua Qingwen (LHQW) is a commonly used Chinese medical preparation to treat viral influenza, including in the fight against SARS in 2002-2003 in China. Recent data also showed that LHQW played a vigorous role in COVID-19 treatment. PURPOSE: This review will elucidate the pre-clinical and clinical evidence of LHQW in lung protection and antiviral activities, and provide timely data delivery for the exploration of effective treatment strategies in the therapy of COVID-19. STUDY DESIGN AND METHOD: The research data were obtained from the academic databases (up to August 8, 2020) including Pubmed, CNKI and Web of Science, on ethnobotany and ethno medicines. The search keywords for screening the literature information were "virus", "COVID-19", or "SARS-CoV-2", and "Lianhua Qingwen". The documents were filtered and summarized for final evaluation. RESULTS: The collected evidence demonstrated that LHQW exhibited benefits against COVID-19. Impressively, LHQW in conjunction with conventional treatment could significantly improve COVID-19 patients as a synergetic strategy. The mechanisms were mainly involved the antiviral activity, and regulation of inflammation response as well as immune function. CONCLUSION: Although the data were far from adequate, the latest advances had shown the benefits of LHQW in COVID-19, especially in combination with other antiviral drugs. This review provides comprehensive evidence of LHQW as a complementary strategy for treating COVID-19. Nevertheless, imperious researches should be conducted to clarify the unconfirmed effects, regulatory mechanisms and adverse reactions of LHQW in treating COVID-19 by means of well designed randomized controlled trials.

The ERV-9 LTR enhancer is not blocked by the HS5 insulator and synthesizes through the HS5 site non-coding, long RNAs that regulate LTR enhancer function.

A solitary long terminal repeat (LTR) of ERV-9 human endogenous retrovirus is located upstream of the HS5 site in the human beta-globin locus control region and possesses unique enhancer activity in erythroid K562 cells. In cells transfected with plasmid LTR-HS5-epsilonp-GFP, the LTR enhancer activates the GFP reporter gene and is not blocked by the interposed HS5 site, which has been reported to have insulator function. The LTR enhancer initiates synthesis of long RNAs from the LTR promoter through the intervening HS5 site into the epsilon-globin promoter and the GFP gene. Synthesis of the sense, long LTR RNAs is correlated with high level synthesis of GFP mRNA from the epsilon-globin promoter. Mutations of the LTR promoter and/or the epsilon-globin promoter show that (i) the LTR enhancer can autonomously initiate synthesis of LTR RNAs independent of the promoters and (ii) the LTR RNAs are not processed into GFP mRNA or translated into GFP. However, reversing the orientation of the LTR in plasmid (LTR)rev-HS5-epsilonp-GFP, thus reversing the direction of synthesis of LTR RNAs in the antisense direction away from the epsilon-globin promoter and GFP gene drastically reduces the level of GFP mRNA and thus LTR enhancer function. The results suggest that the LTR-assembled transcription machinery in synthesizing non-coding, LTR RNAs can reach the downstream epsilon-globin promoter to activate transcription of the GFP gene.