Aquaporins: Important players in the cardiovascular pathophysiology.

Aquaporin is a membrane channel protein widely expressed in body tissues, which can control the input and output of water in cells. AQPs are differentially expressed in different cardiovascular tissues and participate in water transmembrane transport, cell migration, metabolism, inflammatory response, etc. The aberrant expression of AQPs highly correlates with the onset of ischemic heart disease, myocardial ischemia-reperfusion injury, heart failure, etc. Despite much attention to the regulatory role of AQPs in the cardiovascular system, the translation of AQPs into clinical application still faces many challenges, including clarification of the localization of AQPs in the cardiovascular system and mechanisms mediating cardiovascular pathophysiology, as well as the development of cardiovascular-specific AQPs modulators.Therefore, in this study, we comprehensively reviewed the critical roles of AQP family proteins in maintaining cardiovascular homeostasis and described the underlying mechanisms by which AQPs mediated the outcomes of cardiovascular diseases. Meanwhile, AQPs serve as important therapeutic targets, which provide a wide range of opportunities to investigate the mechanisms of cardiovascular diseases and the treatment of those diseases.

Licoflavone A Suppresses Gastric Cancer Growth and Metastasis by Blocking the VEGFR-2 Signaling Pathway.

Objectives: Licoflavone A (LA) is a natural flavonoid compound derived from the root of Glycyrrhiza. This study investigated the antitumor effect and underlying molecular mechanisms of LA against gastric cancer (GC) in vitro and in vivo. Materials and Methods: A CCK8 assay was used to measure the antiproliferative activity of LA in human GC SGC-7901, MKN-45, MGC-803 cells, and human GES-1 cells. Target prediction and protein-protein interaction (PPI) analysis were used to identify the potential molecular targets of LA. The binding pattern of LA to VEGFR-2 was analyzed by molecular docking and molecular dynamic (MD). The affinity of LA for VEGFR-2 was determined by microscale thermophoresis (MST). The protein tyrosine kinase activity of VEGFR-2 in the presence of LA was determined by an enzyme activity test. The effect of LA on the proliferation of VEGF-stimulated MKN-45 cells was measured with CCK8 assays, clone formation assays, and 3D microsphere models. Hoechst 33342 staining, FCM, MMP, and WB assays were used to investigate the ability of LA to block cell cycle and promote apoptosis of VEGF-stimulated MKN-45 cells. Transwell matrix assays were used to measure migration and invasion, and WB assays were used to measure EMT. Results: LA inhibited the proliferation of SGC-7901, MKN-45, and MGC-803 cells and VEGF-stimulated MKN-45 cells. VEGFR-2 was identified as the target of LA. LA could also block cell cycle, induce apoptosis, and inhibit migration, invasion, and EMT of VEGF-stimulated MKN-45 cells. Functional analyses further revealed that the cytotoxic effect of LA on VEGF-stimulated MKN-45 cells potentially involved the PI3K/AKT and MEK/ERK signaling pathways. Conclusions: This study demonstrates that LA has anti-GC potency in vitro and in vivo. LA affects the proliferation, cycle, apoptosis, migration, invasion, and EMT by targeting VEGFR-2 and blocks the PI3K/AKT and MEK/ERK signaling pathways in VEGF-stimulated MKN-45 cells.

Bellidifolin Inhibits Proliferation of A549 Cells by Regulating STAT3/COX-2 Expression and Protein Activity.

OBJECTIVES: Bellidifolin (BEL) is one type of tetraoxygenated xanthone that is particularly found in Swertia and Gentiana (Gentianaceae). Despite its broad range of pharmacological activities, it is still unclear whether BEL could be used for lung cancer treatment. Hence, we presently demonstrate the roles of BEL towards the proliferative inhibition of the prototypical A549 lung cancer cells. MATERIALS AND METHODS: The antiproliferative activity of BEL was initially verified by cellular experiments. A network pharmacology method was then pursued to assess BEL potential molecular targets from the platform for pharmacological analysis of Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP). Disease enrichment of potential targets and construction of compound-target-disease network maps were performed based on a total of 20 diseases. Two core targets related to the BEL-mediated effect in A549 cells were obtained by importing potential targets into a protein-protein interaction database (STRING) and also analyzing respective data of related targets into this database. Last, these core targets were examined by in vitro analysis and molecular docking. RESULTS: CCK8 assays indicated that treatment with 50-100 µm BEL had an inhibitory effect on the proliferation of human A549 lung cancer cells, whereas this effect was time- and concentration-dependent. As control, treatment with 50-100 µm BEL did not inhibit the proliferation of normal lung epithelial cells (BEAS-2b cell line). H&E staining of BEL-treated A549 cells showed that, upon an increase of drug concentration, nuclear condensation and fragmentation were largely observed. Cell cycle analysis showed that in vitro treatment with 75-100 µm BEL could block A549 cells in S and G2 phases. Western blot analyses showed that after 72 hours of BEL treatment, the level of caspase-8/3 in A549 cells increased, and the level of PARP1 decreased in a dose-dependent manner. Network pharmacology analysis also indicated that lung cancer was the major disease susceptible to BEL treatment. At the same time, STAT3 and COX-2 were identified as two core targets of BEL in lung cancer treatment. Functional analyses further revealed that the cytotoxicity effect of BEL in A549 cells potentially involved the STAT3/COX-2 pathway. Moreover, molecular docking analysis indicated that BEL structure properly matches with COX-2 and STAT3 in space shape, thus illustrating the putative molecular mechanism of BEL's anticancer effect. CONCLUSIONS: Based on a series of in vitro analyses, network pharmacology, and molecular docking, the potential mechanism involving the antiproliferative and cytotoxic effects of BEL in lung cancer cells was investigated. Our study may help providing some theoretical basis for the discovery of novel phytotherapy drugs applicable for the treatment of lung cancer.