RNA m6A methylation and regulatory proteins in pulmonary arterial hypertension.

m6A (N6­methyladenosine) is the most common and abundant apparent modification in mRNA of eukaryotes. The modification of m6A is regulated dynamically and reversibly by methyltransferase (writer), demethylase (eraser), and binding protein (reader). It plays a significant role in various processes of mRNA metabolism, including regulation of transcription, maturation, translation, degradation, and stability. Pulmonary arterial hypertension (PAH) is a malignant cardiopulmonary vascular disease characterized by abnormal proliferation of pulmonary artery smooth muscle cells. Despite the existence of several effective and targeted therapies, there is currently no cure for PAH and the prognosis remains poor. Recent studies have highlighted the crucial role of m6A modification in cardiovascular diseases. Investigating the role of RNA m6A methylation in PAH could provide valuable insights for drug development. This review aims to explore the mechanism and function of m6A in the pathogenesis of PAH and discuss the potential targeting of RNA m6A methylation modification as a treatment for PAH.

Role of macrophages in pulmonary arterial hypertension.

Pulmonary arterial hypertension (PAH) is a severe cardiopulmonary vascular disease characterized by progressive pulmonary artery pressure elevation, increased pulmonary vascular resistance and ultimately right heart failure. Studies have demonstrated the involvement of multiple immune cells in the development of PAH in patients with PAH and in experimental PAH. Among them, macrophages, as the predominant inflammatory cells infiltrating around PAH lesions, play a crucial role in exacerbating pulmonary vascular remodeling in PAH. Macrophages are generally polarized into (classic) M1 and (alternative) M2 phenotypes, they accelerate the process of PAH by secreting various chemokines and growth factors (CX3CR1, PDGF). In this review we summarize the mechanisms of immune cell action in PAH, as well as the key factors that regulate the polarization of macrophages in different directions and their functional changes after polarization. We also summarize the effects of different microenvironments on macrophages in PAH. The insight into the interactions between macrophages and other cells, chemokines and growth factors may provide important clues for the development of new, safe and effective immune-targeted therapies for PAH.

Cornuside Is a Potential Agent against Alzheimer's Disease via Orchestration of Reactive Astrocytes.

Cornuside is an iridoid glycoside from Cornus officinalis, with the activities of anti-inflammatory, antioxidant, anti-mitochondrial dysfunction, and neuroprotection. In the present research, a triple-transgenic mice model of AD (3 × Tg-AD) was used to explore the beneficial actions and potential mechanism of cornuside on the memory deficits. We found that cornuside prominently alleviated neuronal injuries, reduced amyloid plaque pathology, inhibited Tau phosphorylation, and repaired synaptic damage. Additionally, cornuside lowered the release of interleukin-1ß (IL-1ß), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and nitric oxide (NO), lowered the level of malondialdehyde (MDA), and increased the activity of superoxide dismutase (SOD) and the level of glutathione peroxidase (GSH-Px). Cornuside also significantly reduced the activation of astrocytes and modulated A1/A2 phenotypes by the AKT/Nrf2/NF-κB signaling pathway. We further confirmed that LY294002 and Nrf2 silencing could block the cornuside-mediated phenotypic switch of C6 cells induced by microglia conditioned medium (MCM) in response to lipopolysaccharide (LPS), which indicated that the effects of cornuside in astrocyte activation are dependent on AKT/Nrf2/NF-κB signaling. In conclusion, cornuside may regulate the phenotypic conversion of astrocytes, inhibit neuroinflammation and oxidative stress, improve synaptic plasticity, and alleviate cognitive impairment in mice through the AKT/Nrf2/NF-κB axis. Our present work provides an experimental foundation for further research and development of cornuside as a candidate drug for AD management.

L-Carnitine Alleviates the Myocardial Infarction and Left Ventricular Remodeling through Bax/Bcl-2 Signal Pathway.

Purpose: L-carnitine (LC) is considered to have good therapeutic potential for myocardial infarction (MI), but its mechanism has not been clarified. The aim of the study is to elucidate the cardioprotective effects of LC in mice following MI and related mechanisms. Methods: ICR mice were treated with LC for 2 weeks after induction of MI with ligation of left anterior descending artery. Electrocardiographic (ECG) recording and echocardiography were used to evaluate cardiac function. H&E staining, TTC staining, and Masson staining were performed for morphological analysis and cardiac fibrosis. ELISA and immunofluorescence were utilized to detect biomarkers and inflammatory mediators. The key proteins in the Bax/Bcl-2 signaling pathway were also examined by Western blot. Results: Both echocardiography and histological measurement showed an improvement in cardiac function and morphology. Biomarkers such as LDH, NT-proBNP, cTnT, and AST, as well as the inflammatory cytokines IL-1ß, IL-6, and TNF-α, were decreased in plasma of mice receiving LC treatment after myocardial injury. In addition, the expression of α-SMA as well as the key proteins in the Bax/Bcl-2 signaling pathway in cardiac myocardium were much lower in mice with LC treatment compared to those without after MI. Conclusions: Our data suggest that LC can effectively ameliorate left ventricular (LV) remodeling after MI, and its beneficial effects on myocardial function and remodeling may be attributable at least in part to anti-inflammatory and inhibition of the Bax/Bcl-2 apoptotic signaling pathway.

Luteolin alleviates cognitive impairment in Alzheimer's disease mouse model via inhibiting endoplasmic reticulum stress-dependent neuroinflammation.

Luteolin is a flavonoid in a variety of fruits, vegetables, and herbs, which has shown anti-inflammatory, antioxidant, and anti-cancer neuroprotective activities. In this study, we investigated the potential beneficial effects of luteolin on memory deficits and neuroinflammation in a triple-transgenic mouse model of Alzheimer's disease (AD) (3 × Tg-AD). The mice were treated with luteolin (20, 40 mg · kg-1 · d-1, ip) for 3 weeks. We showed that luteolin treatment dose-dependently improved spatial learning, ameliorated memory deficits in 3 × Tg-AD mice, accompanied by inhibiting astrocyte overactivation (GFAP) and neuroinflammation (TNF-α, IL-1ß, IL-6, NO, COX-2, and iNOS protein), and decreasing the expression of endoplasmic reticulum (ER) stress markers GRP78 and IRE1α in brain tissues. In rat C6 glioma cells, treatment with luteolin (1, 10 µM) dose-dependently inhibited LPS-induced cell proliferation, excessive release of inflammatory cytokines, and increase of ER stress marker GRP78. In conclusion, luteolin is an effective agent in the treatment of learning and memory deficits in 3 × Tg-AD mice, which may be attributable to the inhibition of ER stress in astrocytes and subsequent neuroinflammation. These results provide the experimental basis for further research and development of luteolin as a therapeutic agent for AD.

[Chemical constituents from ripe fruit of Cornus officinalis].

To investigate the chemical compounds from the fruit of Cornus officinalis, six compounds were isolated and determined by extensive spectroscopic analysis as 6'-O-acetyl-7α-O-ethyl morroniside (1), (-)-isolariciresinol 3α-O-ß-D-glucopyranoside(2), apigenin (3), cirsiumaldehyde(4), p-coumaric acid (5), caffeic acid (6). Compound 1 was a new iridoid glucoside,and compounds 2-4 were obtained from the Cornus genus for the first time. Compounds 2-6 were evaluated for the viability of PC12 cells when exposed in conditions of oxygen and glucose deprivation. The MTT results showed that compound 4 increased cell viability moderately in OGD/R treated PC12 cells at the concentration of 1.0 µmol•L⁻¹.

[Effects of Aptamer-siRNA Nucleic Acid Compound on Growth and Apoptosis in Myeloid Leukemia Cell Line K562].

OBJECTIVE: To explore the effects of aptamer-siRNA nucleic acid compound on growth and apoptosis in myeloid leukemia cell line K562. METHODS: the changes of cellular morphology and structure were observed by using fluorescence microscope, laser confocal microscope, JEM-4000EX transmission electron microscopy; MTT assay were performed to evaluate the sensibility of K562 cells to aptamer-siRNA compound, the apoptosis was detected by DNA gel electro-phoresis. RESULTS: The remarkably changes of morphology and structure of K562 cells treated with 200 µmol/L aptamer-siRNA were observed under fluorescence microscopy and electromicroscopy. As compared with control, the aptamer-siRNA compound showed more inhibitory effect on K562 cells and there was significant difference (P<0.05). The MTT assay showed that the IC50 value of aptamer-siRNA compound for K562 cells was 150 µmol/L. According to agarose gel electrophoresis observation, when the aptamer-siRNA compound showed effect on K562 cells, the typical DNA lader could be observed. CONCLUSION: The aptamer-siRNA compound can significantly induce K562 cell apoptosis, and provide reference for gene therapy of patients with chronic myelocytic lenkemia.

Antithrombotic effects of the effective components group of Xiaoshuantongluo formula in vivo and in vitro.

The present study was designed to investigate the antithrombotic effects and underlying mechanisms of the effective components group (ECG) of Xiaoshuantongluo recipe (XECG) and to further verify the rationality and feasibility of ECG-guided methodology in traditional Chinese medicine (TCM) research. The arterial thrombosis model induced by ferric chloride (FeCl3) oxidation and the venous thrombosis model induced by inferior vena cava ligation were established to evaluate the antithrombotic potential of XECG. Our results indicated that XECG significantly prolonged the time to occlusion, activated partial thromboplastin time (APTT), and prothrombin time (PT), and markedly inhibited adenosine diphosphate (ADP)-induced platelet aggregation in the 20% FeCl3-induced arterial thrombosis model. The superoxide dismutase (SOD) activity was significantly increased and the levels of malondialdehyde (MDA) and nitric oxide (NO) were dramatically decreased in the plasma of arterial thrombosis rats after XECG treatment for 12 days. Furthermore, XECG markedly reduced the weight of thrombus formed by inferior vena cava ligation. Additionally, XECG exhibited 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity and protective effect on mitochondrial lipid peroxidation. In summary, XECG played an important role in the prevention of thrombosis through interacting with multiple targets, including inhibition of platelet aggregation and coagulation and repression of oxidative stress. The ECG-guided methodology was validated as a feasible tool in TCM research.

[Effects of paclitaxel loaded-drug micelles on cell proliferation and apoptosis of human lung cancer A549 cells].

This study was conducted to investigate the paclitaxel loaded by hydrazone bonds in poly(ethylene glycol)-poly(caprolactone) micelles (mPEG-PCL-PTX) on proliferation and apoptosis of human lung cancer A549 cells and its possible mechanisms of anti-tumor activity. The cell proliferation was measured with MTT assay. Flow cytometry were used to analyze the cell cycle. The cell apoptosis was analyzed using Hoechst/P staining. The expression levels of apoptotic genes expression in the mitochondrial apoptosis pathway were detected by RT-PCR and Western blotting, respectively. The mPEG-PCL-PTX could inhibit the proliferation of A549 cells and promote the apoptosis. The Bax, caspase-3 protein expression were increased while Bcl-2 protein expression was decreased in A549 cells. Results showed that the polymer containing hydrazone bond is non-toxic in vitro, the mPEG-PCL-PTX micelles can inhibit the proliferation and induce the apoptosis of A549 cells. Key words: paclitaxel; micelle; A549 cell; proliferation; cell cycle; apoptosis

[Neuroprotective effects of the effective components group of xiaoshuantongluo against oxygen-glucose deprivation in primary cultured rat cortical neurons].

This study is to investigate the effect of the effective components group of Xiaoshuantongluo (XECG) on neuronal injury induced by oxygen-glucose deprivation (OGD) in primary cortical cultures isolated from SD rat cortex at day 3 and the possible mechanism. Cells were divided into control group, OGD model group and XECG group (1, 3 and 10 mg x L(-1)). The cell viability was assessed with MTT assay and the LDH release rate was measured by enzyme label kit. The cell apoptosis was analyzed using Hoechst staining. RT-PCR was applied to detect the mRNA levels of JAK2 and STAT3. Western blotting was used to detect the expressions of Bcl-2, Bax, p-JAK2 and p-STAT3 proteins. Results showed that XECG resulted in an obvious resistance to oxygen-glucose deprivation-induced cell apoptosis and decrement of cell viability, decrease the cell LDH release rate. XECG could adjust the expression of Bcl-2 and Bax proteins and increase Bcl-2/Bax ratio, up-regulate the expression of p-JAK2 and p-STAT3. In conclusion, XECG could protect against the neuronal injury cells exposed to OGD, which may be relevant to the promotion of JAK2/STAT3 signaling pathway, and impact the expression of Bax and Bcl-2.

[Protective effect of mailuoning injection on cerebral ischemia/reperfusion injury in rats and its mechanism].

OBJECTIVE: To discuss the protective effect of Mailuoning injection on ischemia/reperfusion (I/R) injury in rats and its mechanism. METHOD: Healthy male adult Sprague-Dawley (SD) rats were randomly divided into the sham operation group, the model group, the edaravone (3 mg x kg(-1)) control group, and Mailuoning high, middle and low-dose groups (4, 2, 1 mL x kg(-1)), with 10 rats in each group, and administered with drugs through tail intravenous injection. The middle cerebral artery occlusion (MCAO) was adopted to establish the rat ischemia/reperfusion model. After the ischemia for 2 h and reperfusion for 24 h, the pathological changes in neurovascular units (NVU) of brain tissues at the ischemia side was observed by HE staining. The expressions of glialfibrillary acidic protein (GFAP) and ionized calcium-binding adaptor molecule 1 (Ibal) were detected by the immunohistochemical method. The expressions of tumor necrosis factor-alpha (TNF-alpha), interleukin 1beta (IL-1beta), vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) were detected by the western blotting technique. RESULT: Mailuoning injection could significantly improve the pathological changes in cortical penumbra brain tissue UVN of (I/R) rats, reduce the number of GFAP and Ibal positive cells, and significantly decrease the expressions of TNF-alpha, IL-1beta, VCAM-1 and ICAM-1 of brain tissues of I/R rats. CONCLUSION: Mailuoning injection shows an obvious protective effect on UVN of I/R rats. Its mechanism may involve the inhibition of the activation of astrocyte and microglia and the secretion and expression of various inflammatory factors.