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The establishment of porcine pluripotent stem cells (piPSCs) is critical but remains challenging. All piPSCs are extremely sensitive to minor perturbations of culture conditions and signaling network. Inhibitors, such as CHIR99021 and XAV939 targeting the WNT signaling pathway, have been added in a culture medium to modify the cell regulatory network. However, potential side effects of inhibitors could confine the pluripotency and practicability of piPSCs. This study aimed to investigate the roles of AXIN, one component of the WNT pathway in piPSCs. Here, porcine AXIN1 and AXIN2 genes were knocked-down or overexpressed. Digital RNA-seq was performed to explore the mechanism of cell proliferation and apoptosis. We found that (1) overexpression of the porcine AXIN2 gene significantly reduced survival and negatively impacted the pluripotency of piPSCs, and (2) knockdown of AXIN2, a negative effector of the WNT signaling pathway, enhanced the expression of genes involved in cell cycle but reduced the expression of genes related to cell differentiation, death, and apoptosis.

Background: miRNAs are single-stranded, small RNA molecules with a length of 18-25 nucleotides. They bind to the 3' untranslated regions of mRNA transcripts to reduce the translation of these transcripts or to cause their degradation. The roles of these molecules differ in biological processes, such as cell differentiation, proliferation, apoptosis and tumor genesis. miRNA-33 is encoded by the gene introns of proteins that bind sterol-regulatory elements. This molecule cooperates with these proteins to control cholesterol homeostasis, fatty acid levels and the genes that are related to the expression of fat metabolism. The examination of miR-33 expression and its target genes can promote the in-depth study of the miRNA regulation mechanism in the formation process of goose fatty liver and can lay a foundation for research into human fatty liver. Methodology/principal findings: (1) Through real-time fluorescent quantitative polymerase chain reaction (TaqMan MicroRNA Assay), we detected the expression of miR-33 during the feeding of Landes geese. The expression level of miR-33 increases significantly in the liver after 19 days in comparison with the control group; (2) By using the bioinformatics software programs TargetScan, miRDB and miRCosm to predict the target genes of miR-33 according to laboratory prophase transcriptome results and references, we screen nine target genes: adenosine triphosphate binding cassette transporters A1, adenosine triphosphate binding cassette transporters G1, Neimann Pick C, carnitine O-octanoyltransferase (CROT), cyl-CoA dehydrogenase/3-ketoacyl-CoA thiolase/enoyl-CoA hydratase, beta subunit (HADHB), AMP-activated protein kinase, alpha subunit 1 (AMPKα1), insulin receptor substrate 2, glutamic pyruvate transaminase and adipose differentiation-related protein. The dual luciferase reporter gene system in the CHO cell line verifies that CROT, HADHB and NPC1 are the target genes of miR-33 in geese. The inhibition rate of CROT is highest and reaches 70%; (3) The seed sequence (5' 2-8 bases) is the acting site of miR-33. The two predicted target sites of CROT are the target sites of miR-33. Moreover, the predicted target site of HADHB and NPC1 is the target site of miR-33. Conclusions/significance: (1) After 19 days of overfeeding, the expression level of miR-33 increases significantly in the livers of geese; (2) CROT, HADHB and NPC1 are the target genes of miR-33 in geese. These genes determine the combined target site. [ABSTRACT FROM AUTHOR]

The therapeutic effect of stroke is hampered by the lack of neuroprotective drugs against ischemic insults beyond the acute phase. Carnitine plays important roles in mitochondrial metabolism and in modulating the ratio of coenzyme A (CoA)/acyl-CoA. Here, we investigate the neuroprotective effects of L-carnitine (LC) and Acetyl-L-carnitine (ALC) pre-treatment on ischemic insults under the same experimental conditions. We used a transient middle cerebral artery occlusion (MCAO) model to evaluate the protective roles of LC and ALC in acute focal cerebral ischemia in vivo and to understand the possible mechanisms using model of PC12 cell cultures in vitro. Results showed that ALC, but not LC, decreased infarction size in SD rats after MCAO in vivo. However, both LC and ALC pretreatment reduced oxygen-glucose deprivation (OGD)-induced cell injury and decreased OGD-induced cell apoptosis and death in vitro; at the same time, both of them increased the activities of super oxide dismutase (SOD) and ATPase, and decreased the concentration of malondialdehyde (MDA) in vitro. Thus, our findings suggested that LC and ALC pre-treatment are highly effective in the prevention of neuronal cell against ischemic injury in vitro, however, only ALC has the protective effect on neuronal cell injury after ischemia in vivo. [ABSTRACT FROM AUTHOR]

Recently, we demonstrated that myricetin exhibits cytoprotective effects against H2O2-induced cell damage via its antioxidant properties. In the present study, myricetin was found to inhibit H2O2-induced apoptosis in Chinese hamster lung fibroblast (V79-4) cells, as shown by decreased apoptotic bodies, nuclear fragmentation, sub-G1 cell population, and disruption of mitochondrial membrane potential (ΔΨm), which are increased in H2O2-treated cells. Western blot data showed that in H2O2-treated cells, myricetin increased the level of Bcl-2, which is an anti-apoptotic factor, and decreased the levels of Bax, active caspase-9 and -3, which are pro-apoptotic factors. And myricetin inhibited release of cytochrome c from mitochondria to cytosol in H2O2-treated cells. Myricetin-induced survival correlated with Akt activity, and the rescue of cells by myricetin treatment against H2O2-induced apoptosis was inhibited by the specific PI3K (phosphoinositol-3-kinase) inhibitor. Myricetin-mediated survival also inhibited the activation of p38 mitogen activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK), which are members of MAPK. Our studies suggest that myricetin prevents oxidative stress-induced apoptosis via regulation of PI3K/Akt and MAPK signaling pathways. [ABSTRACT FROM AUTHOR]