Search

Simple Summary: Lactoferrin (LF) is considered to be an important active protein in goat milk, and it plays an important role in immunity. In this study, we tried to find factors affecting the expression of lactoferrin. Furthermore, we further explored the anti-inflammatory effect of LF and related molecular mechanisms in order to further understand how lactoferrin affects the immune system and provide a reference for further study and application of lactoferrin in the future. Lactoferrin (LF) is believed to be an important active protein in goat milk, which plays an anti-inflammatory role. Although LF has been reported to be associated with body health, its exact underlying mechanism remains unclear. Here, we aimed to elucidate the mechanism of this anti-inflammatory effect of LF in vitro. We first identified that miR-214-5p inhibited the expression of LF mRNA and protein in cells through the 3′UTR of LF mRNA. We next identified the alterations in miRNA following LF overexpression in goat mammary epithelial cells (GEMCs). Overexpression of LF significantly increased (p < 0.05) miR-224-5p expression. We further revealed that transcriptional activation of ADAM17, TNF-α, IL-1β, and IL-6 was efficiently decreased (p < 0.05) in GMECs treated by miR-224-5p mimic. Conversely, knockdown of miR-224-5p increased (p < 0.05) ADAM17, TNF-α, IL-1β, and IL-6 expression. Additionally, TNF-α, IL-1β, and IL-6 expression levels were dramatically decreased in GMECs after administration of siADAM17. Herein, we indicate that the miR-214-5p/LF/miR-224-5p/ADAM17 axis is involved in the immune regulation of GEMCs. [ABSTRACT FROM AUTHOR]

Background. Atractylodes lancea (AL) has been used in traditional Chinese medicine for the treatment of various diseases including digestive disorders. Ulcerative colitis (UC) is a common digestive system disease with a low cure rate and easy recurrence. However, it is still not clear whether AL is suitable for UC treatment. Currently, stir-baking with wheat bran is most commonly used to process AL. Here, we aimed to address the effects of the crude and bran-processed AL on UC in vitro and uncover the underlying mechanism based on regulating the IKK/NF-kappa B signaling pathway. Methods. Human colonic epithelial cells (HCoEpiC) were treated with lipopolysaccharide (LPS) to mimic the inflammatory injury of UC in vitro. The essential oil from crude and bran-processed AL was used to treat LPS-induced HcoEpiC cells. The cell viability was detected by an MTT assay. The levels of IL-4, IL-6, IL-8, IL-12, IL-1-β, TNF-α, and NO were determined by ELISA, and the mRNA expressions of IKK-α, NF-κB, IL-4, IL-6, IL-8, and TNF-α were determined by RT-PCR. Meanwhile, the expressions of IKK-α, p-IKK-α, p-IKK-β, NF-κB, IL-6, and IL-8 proteins were determined by Western blot. Results. The essential oil of AL, whether it was from crude or bran-processed AL, could significantly increase the viability of LPS-induced HCoEpiC cells. The treatment of AL essential oil also notably inhibited the productions of IL-6, IL-8, IL-12, IL-1-β, TNF-α, NO, p-IKK-α, p-IKK-β, and NF-κB and downregulated the mRNA expressions of NF-κB, IL-6, IL-8, and TNF-α. Meanwhile, IL-4 protein and mRNA expression were significantly stimulated by AL essential oil. Moreover, the essential oil from bran-processed AL was more effective than that from crude AL. Conclusion. Both kinds of AL essential oil had the anti-inflammatory effect on LPS-induced HCoEpiC, and the essential oil from bran-processed AL was more effective. The mechanism could be through the IKK/NF-κB signaling pathway in vitro. [ABSTRACT FROM AUTHOR]

Following superficial injury, neighbouring gastric epithelial cells close the wound by rapid cell migration, a process called epithelial restitution. Na+/H+ exchange (NHE) inhibitors interfere with restitution, but the role of the different NHE isoforms expressed in gastric pit cells has remained elusive. The role of the basolaterally expressed NHE1 (Slc9a1) and the presumably apically expressed NHE2 (Slc9a2) in epithelial restitution was investigated in the nontransformed rat gastric surface cell line RGM1. Migration velocity was assessed by loading the cells with the fluorescent dye DiR and following closure of an experimental wound over time. Since RGM1 cells expressed very low NHE2 mRNA and have low transport activity, NHE2 was introduced by lentiviral gene transfer. In medium with pH 7.4, RGM1 cells displayed slow wound healing even in the absence of growth factors and independently of NHE activity. Growth factors accelerated wound healing in a partly NHE1-dependent fashion. Preincubation with acidic pH 7.1 stimulated restitution in a NHE1-dependent fashion. When pH 7.1 was maintained during the restitution period, migratory speed was reduced to ∼10% of the speed at pH 7,4, and the residual restitution was further inhibited by NHE1 inhibition. Lentiviral NHE2 expression increased the steady-state pHi and reduced the restitution velocity after low pH preincubation, which was reversible by pharmacological NHE2 inhibition. The results demonstrate that in RGM1 cells, migratory velocity is increased by NHE1 activation, while NHE2 activity inhibit this process. A differential activation of NHE1 and NHE2 may therefore, play a role in the initiation and completion of the epithelial restitution process. [ABSTRACT FROM AUTHOR]

SIRT1, a class III histone deacetylase, acts as a negative regulator for many transcription factors, and plays protective roles in inflammation and atherosclerosis. Transcription factor nuclear factor of activated T cells (NFAT) has been previously shown to play pro-inflammatory roles in endothelial cells. Inhibition of NFAT signaling may be an attractive target to regulate inflammation in atherosclerosis. However, whether NFAT transcriptional activity is suppressed by SIRT1 remains unknown. In this study, we found that SIRT1 suppressed NFAT-mediated transcriptional activity. SIRT1 interacted with NFAT, and the NHR and RHR domains of NFAT mediated the interaction with SIRT1. Moreover, we found that SIRT1 primarily deacetylated NFATc3. Adenoviral over-expression of SIRT1 suppressed PMA and calcium ionophore Ionomycin (PMA/Io)-induced COX-2 expression in human umbilical vein endothelial cells (HUVECs), while SIRT1 RNAi reversed the effects in HUVECs. Moreover, inhibition of COX-2 expression by SIRT1 in PMA/Io-treated HUVECs was largely abrogated by inhibiting NFAT activation. Furthermore, SIRT1 inhibited NFAT-induced COX-2 promoter activity, and reduced NFAT binding to the COX-2 promoter in PMA/Io-treated HUVECs. These results suggest that suppression of NFAT transcriptional activity is involved in SIRT1-mediated inhibition of COX-2 expression induced by PMA/Io, and that the negative regulatory mechanisms of NFAT by SIRT1 may contribute to its anti-inflammatory effects in atherosclerosis. [ABSTRACT FROM AUTHOR]

Expression of glutathione peroxidase 3 (GPx3) is down-regulated in a variety of human malignancies. Both methylation and deletion of GPx3 gene underlie the alterations of GPx3 expression in prostate cancer. A strong correlation between the down-regulation of GPx3 expression and progression of prostate cancer and the suppression of prostate cancer xenografts in SCID mice by forced expression of GPx3 suggests a tumor suppression role of GPx3 in prostate cancer. However, the mechanism of GPx3-mediated tumor suppression remains unclear. In this report, GPx3 was found to interact directly with p53-induced gene 3 (PIG3). Forced overexpression of GPx3 in prostate cancer cell lines DU145 and PC3 as well as immortalized prostate epithelial cells RWPE-1 increased apoptotic cell death. Expression of GPx3x73c, a peroxidase-negative OPAL codon mutant, in DU145 and PC3 cells also increased cell death. The induced expression of GPx3 in DU145 and PC3 cells resulted in an increase in reactive oxygen species and caspase-3 activity. These activities were abrogated by either knocking down PIG3 or mutating the PIG3 binding motif in GPx3 or binding interference from a peptide corresponding to PIG3 binding motif in GPx3. In addition, UV-treated RWPE-1 cells underwent apoptotic death, which was partially prevented by knocking down GPx3 or PIG3, suggesting that GPx3-PIG3 signaling is critical for UV-induced apoptosis. Taken together, these results reveal a novel signaling pathway of GPx3-PIG3 in the regulation of cell death in prostate cancer. [ABSTRACT FROM AUTHOR]