Background and Purpose-Emerging data suggest that neuroglobin (Ngb) may protect against hypoxic/ischemic neuronal insults. However, the underlying mechanisms in vivo and implications for long-term outcomes are still not well understood. Methods-Using our newly created Ngb overexpressing transgenic (Ngb-Tg) mice, we measured brain infarction on day 1 and day 14 after transient focal cerebral ischemia and performed neurobehavioral assessments in sensorimotor deficits on days 1, 3, 7, and 14. To test the hypothesis that Ngb may play a role in reducing oxidative stress after stroke, intracellular malondialdehyde levels were measured and compared in Ngb-Tg and wild-type mice.
Results-Increased
Neuroglobin (Ngb) is a recently discovered tissue globin with a high affinity for oxygen that is widely and specifically expressed in neurons of vertebrate central and peripheral nervous systems. Our laboratory and others have showed Ngb over-expression can protect neurons against hypoxic/ ischemic insults, but the underlying mechanisms remain poorly understood. In this study, we examined the effects of Ngb over-expression on mitochondrial function, oxidative stress and neurotoxicity in primary cortical neurons following hypoxia/reoxygenation (H/R). Ngb overexpressing transgenic neurons (Ngb-Tg) were significantly protected against H/R-induced cell death. Rates of decline in ATP levels, MTT reduction and mitochondrial membrane potential were significantly ameliorated in Ngb-Tg neurons. Furthermore, Ngb overexpression reduced superoxide anion generation after H/R, whereas glutathione levels were significantly improved compared to WT controls. Taken together, these data suggest that Ngb is neuroprotective against hypoxia, in part by improving mitochondria function and decreasing oxidative stress.
Quality control (QC) for lab-designed primers is crucial for the success of a polymerase chain reaction (PCR). Here, we present MFEprimer-3.0, a functional primer quality control program for checking non-specific amplicons, dimers, hairpins and other parameters. The new features of the current version include: (i) more sensitive binding site search using the updated k-mer algorithm that allows mismatches within the k-mer, except for the first base at the 3′ end. The binding sites of each primer with a stable 3′ end are listed in the output; (ii) new algorithms for rapidly identifying self-dimers, cross-dimers and hairpins; (iii) the command-line version, which has an added option of JSON output to enhance the versatility of MFEprimer by acting as a QC step in the ‘primer design → quality control → redesign’ pipeline; (iv) a function for checking whether the binding sites contain single nucleotide polymorphisms (SNPs), which will affect the consistency of binding efficiency among different samples. In summary, MFEprimer-3.0 is updated with the well-tested PCR primer QC program and it can be integrated into various PCR primer design applications as a QC module. The MFEprimer-3.0 server is freely accessible without any login requirement at: https://mfeprimer3.igenetech.com/ and https://www.mfeprimer.com/. The source code for the command-line version is available upon request.
Many growth factors and cytokines are involved in liver regeneration. Of them, only hepatopoietin (HPO)/ALR (augmenter of liver regeneration) is a specifically hepatotrophic factor originally identified from the cytosol of regenerating or hyperplastic hepatic cells. Previous reports indicate that extracellular HPO triggers the MAPK pathway by binding its specific receptor on the cell surface. However, its function in the cytosol of hepatocytes is unclear. Here we identified that JAB1 (Jun activation domain-binding protein 1), a co-activator of AP-1, which is essential for liver regeneration, specifically interacts with intracellular HPO. JAB1 colocalizes with HPO in nuclei of hepatic cells or COS-7 cells. As an intracrine factor, the intracellular function of HPO is to increase c-Jun phosphorylation independent of c-Jun amino-terminal kinase (JNK), extracellular signal-regulated kinase (ERK) -1 and -2, and leads to potentiation of JAB1-mediated AP-1 activation. Amino acids 1-63 of HPO molecule are sufficient to bind to JAB1, but the full-length HPO is necessary for its intracellular signaling. Taken together, these results elucidate a novel mechanism of intracrine cytokine signaling by specifically modulating the AP-1 pathway through JAB1, in a MAPK-independent fashion.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.