Tumor cell motility exhibits a crucial role in tumor development. Therefore, the present study aimed to investigate whether thymol could reduce C6 glioma cell migration. Cell viability was determined using the EZ-Cytox Cell Viability kit. The scratch wound healing and Boyden chamber assays were performed to test C6 glioma cell migration in the presence of fetal bovine serum (FBS). Additionally, the study investigated whether signaling proteins relevant to C6 glioma cell migration, i.e., extracellular signal-regulated kinases (ERK)1/2, protein kinase Cα (PKCα), matrix metallopeptidase (MMP)9 and MMP2, were affected by thymol treatment. Up to 30 µM, thymol did not alter cell viability, whereas 100 µM thymol induced the death of ~20% of the cells. Furthermore, thymol (30 µM) significantly reduced FBS-induced migration. In the FBS-stimulated C6 glioma cells, thymol (30 µM) suppressed PKCα and ERK1/2 phosphorylation. MMP9 and MMP2 production was also significantly reduced by treatment with 30 µM thymol in the C6 glioma cells. Taken together, these results indicate that thymol attenuates C6 glioma cell migration. Additionally, the study suggests that the effect of thymol on the FBS-induced migration of C6 glioma cells affects PKCα and ERK1/2 signaling, and suppresses MMP9 and MMP2 production.
The proliferation and migration of vascular smooth muscle cells (VSMCs) in blood vessels are important in the pathogenesis of vascular disorders such as atherosclerosis and restenosis. Piperine, a major component of black pepper, has antioxidant, anticancer, and anti-inflammatory activity. However, the antiatherosclerotic effects of piperine have not been investigated. In this study, the effects of piperine on platelet-derived growth factor (PDGF)-BB-induced proliferation and migration of VSMCs were investigated. The antiproliferative effects of piperine were determined using MTT assays, cell counting, real-time polymerase chain reaction, and western blots. Our results showed that piperine significantly attenuated the proliferation of VSMCs by increasing the expression of p27(kip1), regulating the mRNA expression of cell cycle enzymes (cyclin D, cyclin E, and PCNA), and decreasing the phosphorylation of extracellular signal-regulated kinase (ERK)1/2 in a noncytotoxic concentration-dependent manner (30-100 μM). Moreover, we examined the effects of piperine on the migration of PDGF-BB-stimulated VSMCs, as determined by the Boyden chamber assay, H2DCFDA staining, and western blots. Our results showed that 100 μM piperine decreased cell migration, the production of reactive oxygen species (ROS), and phosphorylation of the p38 mitogen-activated protein kinase (MAPK). Taken together, our results suggest that piperine inhibits PDGF-BB-induced proliferation and the migration of VSMCs by inducing cell cycle arrest and suppressing MAPK phosphorylation and ROS. These findings suggest that piperine may be beneficial for the treatment of vascular-related disorders and diseases.
The network pharmacology (NP) approach is a valuable novel methodology for understanding the complex pharmacological mechanisms of medicinal herbs. In addition, various in silico analysis techniques combined with the NP can improve the understanding of various issues used in natural product research. This study assessed the therapeutic effects of Arum ternata (AT), Poria cocos (PC), and Zingiber officinale (ZO) on hyperlipidemia after network pharmacologic analysis. A protein–protein interaction (PPI) network of forty-one key targets was analyzed to discover core functional clusters of the herbal compounds. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and gene ontology (GO) term enrichment analysis identified significant categories of hypolipidemic mechanisms. The STITCH database indicated a high connection with several statin drugs, deduced by the similarity in targets. AT, PC, and ZO regulated the genes related to the energy metabolism and lipogenesis in HepG2 cells loaded with free fatty acids (FFAs). Furthermore, the mixture of three herbs had a combinational effect. The herbal combination exerted superior efficacy compared to a single herb, particularly in regulating acetyl-CoA carboxylase (ACC) and carnitine palmitoyltransferase 1 (CPT-1). In conclusion, the network pharmacologic approach was used to assess potential targets of the herbal combination for treatment. Experimental data from FFA-induced HepG2 cells suggested that the combination of AT, PC, and ZO might attenuate hyperlipidemia and its associated hepatic steatosis.
Despite its deleterious effects on living cells, oxidative stress plays essential roles in normal physiological processes and provides signaling molecules for cell growth, differentiation, and inflammation. Macrophages are equipped with antioxidant mechanisms to cope with intracellular ROS produced during immune response, and Nrf2 (NF‐E2‐related factor 2)/HO‐1 (heme oxygenase‐1) pathway is an attractive target due to its protective effect against ROS‐induced cell damage in inflamed macrophages. We investigated the effects of ethanol extract of A. villosum (AVEE) on lipopolysaccharide‐ (LPS‐) stimulated inflammatory responses generated via the Nrf2/HO‐1 signaling pathway in murine peritoneal macrophages and RAW 264.7 cells. AVEE was found to suppress the NF‐κB signaling pathway, thus, to reduce proinflammatory cytokine, nitric oxide, and prostaglandin levels in peritoneal macrophages and Raw 264.7 cells treated with LPS, and to enhance HO‐1 expression by activating Nrf2 signaling. Furthermore, these anti‐inflammatory effects of AVEE were diminished when cells were pretreated with SnPP (a HO‐1 inhibitor). HPLC analysis revealed AVEE contained quercetin, a possible activator of the Nrf2/HO‐1 pathway. These results show A. villosum ethanol extract exerts anti‐inflammatory effects by activating the Nrf2/HO‐1 pathway in LPS‐stimulated macrophages.
Targeting Toll‐like receptor 4/myeloid differentiation factor 2 (TLR4/MD2) signaling is regarded as a potential strategy for treating inflammatory diseases. Saponaria officinalis L. is rich in saponin, which include quillaic acid, gypsogenin, saponarin, and hederagenin. We evaluated the pharmacological activity of a Saponaria officinalis extract in THP‐1 derived macrophages and RAW264.7 macrophages. TLR4/MyD88 complex formation and downstream signals were investigated by co‐immunoprecipitation (Co‐IP). In silico docking simulation was conducted to predict binding scores and perform 3D modeling of saponarin‐TLR4/MD2 complex. A hexane fraction of Saponaria officinalis (SH) and fr.1 (a sub‐fraction 1 of SH) inhibited mitogen‐activated protein kinase (MAPK) signaling, nuclear factor kappa b (NF‐κB) activity, cytokine production, and the expressions of marker genes specific for M1 polarization. The inhibitory effects of fr.1 and saponarin on TLR4/MyD88 complex formation were observed by western blotting TLR4 co‐immunoprecipitated proteins. Saponarin and fr.1 markedly attenuated LPS‐induced inflammatory cytokines, thus reducing mortality and morphological abnormality in zebrafish larvae. Finally, docking simulation revealed that saponarin can directly interact with TLR4/MD2 complex to inhibit downstream signalings. Our findings suggest that saponarin reduces downstream inflammatory response by disrupting TLR4/MD2 complex and blocking MyD88‐dependent inflammatory signaling.