epidermal-growth-factor and cyadox

Cyadox, a new antibacterial agent as the quinoxaline-1, 4-dioxides, has a good antibacterial and growth-promoting effect, and has the advantages of lower toxicity, adequate safety and faster absorption. Seven differential expressed genes (DEGs) induced by cyadox were screened in swine liver tissues, including Insulin-like Growth Factor-1 (IGF-1), Epidermal Growth Factor (EGF), Poly ADP-ribose polymerase (PARP), the Defender Against Apoptotic Death 1 (DAD1), Complement Component 3 (C3), Transketolase (TK) and cyadox-related novel gene (CRNG). To elucidate the signal mechanism that cyadox altered these genes expression, the time-effect relationship and signaling pathways related to 7 DEGs induced by cyadox were determined in Porcine Kidney-15 (PK-15) cells by RT-qPCR and the application of various signal pathway inhibitors. The phosphorylation levels of signal factors in PK-15 cells were detected by Western blot. The analyses demonstrated that, the mRNA expressions of 7 DEGs were significantly enhanced by cyadox mainly through the phosphoinositide 3-kinase (PI3K) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-кB) signaling pathways in PK-15 cells. Furthermore, EGF might be the early response gene of cyadox to activate downstream signaling pathways and regulates the expression of other related genes or directly exerting biological effects. In brief, cyadox mainly regulates the expression of these 7 genes by PI3K and NF-кB signaling pathways to exert it's antibacterial and growth-promoting activity in PK-15 cells.

Topics: Animals; Anti-Bacterial Agents; Cell Line; Epidermal Growth Factor; Gene Expression Regulation; NF-kappa B; Phosphatidylinositol 3-Kinases; Phosphorylation; Quinoxalines; Signal Transduction; Swine; Transcription, Genetic

Cyadox is a novel derivative of quinoxaline-1,4-dioxides (QdNOs) with the potential to be developed as a feed additive. However, the pharmacological and toxicological bioactive molecules of cyadox and the molecular mechanism of its pharmacological and toxic actions remain unclear. In the present study, cyadox and its main metabolites of cy1, cy4, cy6, and cy12 were selected; the growth promotion characteristic was indicated by the mRNA level of EGF; and the cytotoxicity of cyadox was determined by methylthiazol tetrazolium bromide (MTT) assay, lactate dehydrogenase (LDH) release, and Annexin V-FITC/PI apoptosis detection kit with flow cytometry. The intracellular ROS, cyclin D1, and Akt/P53/FOXO1 signaling pathway were also investigated. Our data suggested that cyadox showed relatively higher activity than its metabolites, and the ROS was generated from N-O reduction of cyadox. Moreover, cyadox (2 μM) activated the Akt and increased the EGF, cyclin D1, and FOXO1 expression levels. Cyadox (100 μM) induced cytotoxicity in L02 cells in a concentration- and time-dependent manner. Additionally, the activated P53 pathway, hyperactivated Akt, and apoptosis were found in L02 cells after incubation with 100 μM cyadox. Our data demonstrated that Akt promoted cell survival when it was mildly activated by cyadox at 2 μM, and Akt leads to apoptosis when it was severely activated by cyadox at 100 μM. Thus, the present study revealed that N-O reduction of cyadox and ROS-mediated AKT/FOXO1 and AKT/P53 pathways were involved in growth promotion and cytotoxicity of cyadox.

Topics: Apoptosis; Cell Line; Cell Survival; Epidermal Growth Factor; Forkhead Box Protein O1; Humans; Nitrogen; Oxidation-Reduction; Oxygen; Phosphatidylinositol 3-Kinases; Proto-Oncogene Proteins c-akt; Quinoxalines; Reactive Oxygen Species; Signal Transduction; Tumor Suppressor Protein p53