BML-111, the agonist of lipoxin A4, suppresses epithelial-mesenchymal transition and migration of MCF-7 cells via regulating the lipoxygenase pathway.

Introduction: Aberrant epithelial-mesenchymal transition (EMT) and migration frequently occur during tumour progression. BML-111, an analogue of lipoxin A4, has been implicated in inflammation in cancer research. Methods: 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, western blot, Reverse Transcription Polymerase Chain Reaction (RT-PCR), transwell assay, immunofluorescence, and immunohistochemistry were conducted in this study. Results: In vitro experiments revealed that BML-111 inhibited EMT and migration in CoCl2-stimulated MCF-7 cells. These effects were achieved by inhibiting MMP-2 and MMP-9, which are downregulated by 5-lipoxygenase (5-LOX). Moreover, BML-111 inhibited EMT and migration of breast cancer cells in BALB/c nude mice inoculated with MCF-7 cells. Conclusion: Our results suggest that BML-111 may be a potential therapeutic drug for breast cancer and that blocking the 5-LOX pathway could be a possible approach for mining effective drug targets.

Anti-inflammatory and anti-oxidant properties of Ipomoea nil (Linn.) Roth significantly alleviates cigarette smoke (CS)-induced acute lung injury via possibly inhibiting the NF-κB pathway.

Acute respiratory distress syndrome (ARDS), a serious manifestation of acute lung injury (ALI), is a debilitating inflammatory lung disease that is caused by multiple risk factors. One of the primary causes that can lead to ALI/ARDS is cigarette smoke (CS) and its primary mode of action is via oxidative stress. Despite extensive research, no appropriate therapy is currently available to treat ALI/ARDS, which means there is a dire need for new potential approaches. In our study we explored the protective effects of 70 % methanolic-aqueous extract of Ipomoea nil (Linn.) Roth, named as In.Mcx against CS-induced ALI mice models and RAW 264.7 macrophages because Ipomoea nil has traditionally been used to treat breathing irregularities. Male Swiss albino mice (20-25 ± 2 g) were subjected to CS for 10 uninterrupted days in order to establish CS-induced ALI murine models. Dexamethasone (1 mg/kg), In.Mcx (100 200, and 300 mg/kg) and normal saline (10 mL/kg) were given to respective animal groups, 1 h before CS-exposure. 24 h after the last CS exposure, the lungs and bronchoalveolar lavage fluid (BALF) of all euthanized mice were harvested. Altered alveolar integrity and elevated lung weight-coefficient, total inflammatory cells, oxidative stress, expression of pro-inflammatory cytokines (IL-1ß and IL-6) and chemokines (KC) were significantly decreased by In.Mcx in CS-exposed mice. In.Mcx also revealed significant lowering IL-1ß, IL-6 and KC expression in CSE (4 %)-activated RAW 264.7 macrophage. Additionally, In.Mcx showed marked enzyme inhibition activity against Acetylcholinesterase, Butyrylcholinesterase and Lipoxygenase. Importantly, In.Mcx dose-dependently and remarkably suppressed the CS-induced oxidative stress via not only reducing the MPO, TOS and MDA content but also improving TAC production in the lungs. Accordingly, HPLC analysis revealed the presence of many important antioxidant components. Finally, In.Mcx showed a marked decrease in the NF-κB expression both in in vivo and in vitro models. Our findings suggest that In.Mcx has positive therapeutic effects against CS-induced ALI via suppressing uncontrolled inflammatory response, oxidative stress, lipoxygenase and NF-κB p65 pathway.

Inhibition of spinal 15-LOX-1 attenuates TLR4-dependent, nonsteroidal anti-inflammatory drug-unresponsive hyperalgesia in male rats.

Although nonsteroidal anti-inflammatory drugs are the first line of therapeutics for the treatment of mild to moderate somatic pain, they are not generally considered to be effective for neuropathic pain. In the current study, direct activation of spinal Toll-like 4 receptors (TLR4) by the intrathecal (IT) administration of KDO2 lipid A (KLA), the active component of lipopolysaccharide, elicits a robust tactile allodynia that is unresponsive to cyclooxygenase inhibition, despite elevated expression of cyclooxygenase metabolites in the spinal cord. Intrathecal KLA increases 12-lipoxygenase-mediated hepoxilin production in the lumbar spinal cord, concurrent with expression of the tactile allodynia. The TLR4-induced hepoxilin production was also observed in primary spinal microglia, but not in astrocytes, and was accompanied by increased microglial expression of the 12/15-lipoxygenase enzyme 15-LOX-1. Intrathecal KLA-induced tactile allodynia was completely prevented by spinal pretreatment with the 12/15-lipoxygenase inhibitor CDC or a selective antibody targeting rat 15-LOX-1. Similarly, pretreatment with the selective inhibitors ML127 or ML351 both reduced activity of the rat homolog of 15-LOX-1 heterologously expressed in HEK-293T cells and completely abrogated nonsteroidal anti-inflammatory drug-unresponsive allodynia in vivo after IT KLA. Finally, spinal 12/15-lipoxygenase inhibition by nordihydroguaiaretic acid (NDGA) both prevents phase II formalin flinching and reverses formalin-induced persistent tactile allodynia. Taken together, these findings suggest that spinal TLR4-mediated hyperpathic states are mediated at least in part through activation of microglial 15-LOX-1.