Ampelopsin inhibited apoptosis and migration of SMMC-7721 cells through MAPKs signaling pathway / 药学学报

This research is aimed to investigate the effect of ampelopsin on apoptosis and migration of human hepatoma SMMC-7721 cells and explore the molecular mechanism. SMMC-7721 cells were pretreated with different doses of ampelopsin and cells proliferation was detected by CCK8 kit. Cell morphology was observed under an inverted microscope. Nuclear morphology was detected by DAPI staining. Apoptotic rate was detected by Annexin V-FITC/PI flow cytometry. Migration and invasion were detected by Transwell and scratch healing test. Western blotting was used to detect cleavage of poly ADP-ribose polymerase (PARP), expression of matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9), E-cadherin, and N-cadherin, and phosphorylation of ERK, P38 and JNK in MAPKs pathway. Our results showed that ampelopsin significantly inhibited proliferation and induced apoptosis of SMMC-7721 cells, with half inhibition dose (IC50) for 24 h was 38.98 μg·mL-1. With 50 μg·mL-1 ampelopsin treatment, typical apoptotic morphological changes occurred, such as cell detachment, shrinkage and nuclear condensation. Apoptotic rate increased from 15% to 55.1%, with PARP cleavage significantly increased. In addition, treatment of ampelopsin reduced scratch healing of cells and transmembrane cells number. The expression levels of MMP-2 and MMP-9 were decreased. Further analysis of EMT-related proteins showed that after ampelopsin treatment, E-cadherin was up-regulated and N-cadherin was down-regulated. During ampelopsin treatment, ERK reached its peak of activation after 1 h, while the maximum activation time of JNK was 12 h. Meanwhile, P38 was activated within 4 h, with the highest point at 2 h. But after 4 h, ampelopsin inhibited phosphorylation of P38. These results indicated that ampelopsin induced apoptosis and reduced migration through activating MAPKs pathway and reversing EMT process in SMMC-7721 cells. This work provides a mechanistic basis for utilizing ampelopsin for anti-hepatocarcinoma treatment.

Chrysin inhibits lipopolysaccharide-induced inflammatory responses of macrophages via JAK-STATs signaling pathway / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the mechanism of chrysin in regulating lipopolysaccharide (LPS)-induced inflammation in RAW264.7 cells.</p><p><b>METHODS</b>RAW264.7 cells were treated with different concentrations (0, 5, 10, 20, 40, 60, 80, 100, 150, and 200 µg/mL) of chrysin for 24 h, and the cell viability was measured using CCK-8. RAW264.7 cells were pre-treated with 10, 30, or 60 µg/mL chrysin for 2 h before stimulation with LPS for different times. The levels of TNF-α, IL-6 and MCP-1 were detected by ELISA, and Western blotting was used to detect the phosphorylation of JAK- 1, JAK-2, STAT-1 and STAT-3. The level of reactive oxygen species in RAW264.7 cells was detected by CM-H2DCFDA fluorescence probe. The effect of ROS on LPS-induced JAK-STATs signal and the inflammatory response of RAW264.7 cells was detected by ROS scavenger NAC. The transcription factors STAT-1 and STAT-3 nuclear translocation were observed by laser confocal microscopy.</p><p><b>RESULTS</b>Chrysin below 60 µg/mL did not significantly affect the viability of RAW264.7 cells. At 10, 30, and 60 µg/mL, chrysin dose-dependently inhibited the expression of iNOS induced by LPS. Chrysin treatment also inhibited LPS-induced phosphorylation of JAK-STATs, nuclear translocation of STAT1 and STAT3, release of TNF-α, IL-6 and MCP-1, and the production of ROS in RAW264.7 cells; ROS acted as an upstream signal to mediate the activation of JAK-STATs signaling pathway.</p><p><b>CONCLUSION</b>Chrysin blocks the activity of JAK-STATs mediated by ROS to inhibit LPS-induced inflammatory response in RAW264.7 cells.</p>

Salidroside protects PC12 cells from HO-induced apoptosis via suppressing NOX2-ROS-MAPKs signaling pathway / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the molecular mechanism by which salidroside protects PC12 cells from HO-induced apoptosis.</p><p><b>METHODS</b>PC12 cells cultured in DMEM supplemented with 10% horse serum and 5% fetal bovine serum were pretreated with different doses of salidroside for 2 h and then stimulated with HOfor different lengths of time. The expression levels of PARP and caspase 3 and the phosphorylation of p38, ERK and JNK were determined with Western blotting. The cell nuclear morphology was observed after DAPI staining. The production of ROS was detected using a ROS detection kit, and the levels of gp91and p47in the membrane and cytoplasm were detected by membrane-cytoplasm separation experiment; the binding between gp91and p47was assayed by coimmunoprecipitation experiment.</p><p><b>RESULTS</b>Salidroside dose-dependently suppressed cell apoptosis, lowered phosphorylation levels of p38, ERK and JNK, inhibited the production of ROS, reduced the binding between gp91and p47, and inhibited the activity of NOX2 in PC12 cells exposed to HO.</p><p><b>CONCLUSION</b>Salidroside protects PC12 cells from HO-induced apoptosis at least partly by suppressing NOX2-ROS-MAPKs signaling pathway.</p>

Effect of sodium aescinate in inducing human breast cancer MCF-7 cells apoptosis by inhibiting AKT, ERK and upstream signal SRC activity / 中国中药杂志

To study the effect of sodium aescinate in inducing human breast cancer MCF-7 cells apoptosis and its possible mechanism. MTT assay was used to detect the inhibitory effect of sodium aescinate on the proliferation of MCF-7 cells. The morphological changes were observed under inverted microscope. DAPI nuclear staining was used to detect the changes in cell nucleus. Annexin V-FITC/PI flow cytometry was adopted to test the apoptosis rate. Changes in apoptosis-related proteins (PARP, cleaved caspase-8 and pro-caspase-3), cell survival-associated signal molecules (AKT and ERK) and their common upstream kinase SRC was detected by Western blotting. The result showed that after different concentrations of sodium aescinate were used to treat breast cancer MCF-7 cells, they inhibited the proliferation of MCF-7 cells in a dose-dependent manner, induced cell apoptosis (typical morphological changes in nucleus, significant increase in cell apoptosis rate). The expressions of cleaved PARP and caspase-8 increased, while the expression of pro-caspase-3 decreased, which further verified sodium aescinate's effect in inducing cell apoptosis. Sodium aescinate significantly inhibited the phosphorylation of cell survival-related signal molecules (AKT, ERK) and down-regulate the activation of their common up-stream kinase SRC. The findings indicated that sodium aescinate can block signals transiting to downstream molecules AKT, ERK, inhibit the proliferation of breast cancer cell MCF-7 cell apoptosis and induced cell apoptosis by suppressing the activation of SRC.