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161.
Kim DW Lee JH Park SK Yang WM Jeon GS Lee YH Chung CK Cho SS 《Neurochemical research》2007,32(9):1460-1468
Glycogen synthase kinase 3β (GSK3β) is believed to play important roles in the regulation of synaptic plasticity, cell survival
and circadian rhythms in the mature CNS. However, although several studies have been focused on the GSK3β, little is known
about GSK3β changes in glial cells under neuropathological conditions. In this study, we evaluated the expressions of molecules
associated with the GSK3β signaling pathway, following the induction of an excitotoxic lesion in mouse brain by kainic acid
(KA) injection, which caused pyramidal cell degeneration in the hippocampal CA3 region. In injured hippocampi, Ser47-Akt (protein
kinase B, PKB) phosphorylation increased from 4 h until 1 day post-injection (PI). Ser9-GSK3β and Ser133-cAMP responsive element-binding
protein (CREB) phosphorylations showed similar spatiotemporal patterns in hippocampi at 1 day until 3 days PI. Double immunohistochemistry
also showed that these phosphorylated forms of Akt, GSK3β and CREB were expressed in astrocytes. For the first time, our data
demonstrate the injury-induced astrocytic changes in the levels of phosphorylation of Akt, -GSK3β and -CREB in vivo, which
may reflect mechanisms of glial cells protection or adaptive response to damage.
DW Kim and JH Lee contributed equally to this work. 相似文献
162.
Ko BS Jang JS Hong SM Sung SR Lee JE Lee MY Jeon WK Park S 《Bioscience, biotechnology, and biochemistry》2007,71(6):1452-1461
We hypothesized that roasted Glycyrrhizae Radix (Glycyrrhizin Radix Praeparata, GRP) might modify anti-diabetic action due to compositional changes. Then we examined the anti-diabetic effect and mechanism of raw Glycyrrhizae Radix (GR) and GRP extracts and their major respective components, glycyrrhizin and glycyrrhetinic acid. In partial pancreatectomized (Px) diabetic mice, both GR and GRP improved glucose tolerance, but only GRP enhanced glucose-stimulated insulin secretion as much as exendin-4. Both GR and GRP extracts enhanced insulin-stimulated glucose uptake through peroxisome proliferation-activated receptor (PPAR)-gamma activation in 3T3-L1 adipocytes. Consistently with the results of the mice study, only GRP and glycyrrhetinic acid enhanced glucose-stimulated insulin secretion in isolated islets. In addition, they induced mRNA levels of insulin receptor substrate-2, pancreas duodenum homeobox-1, and glucokinase in the islets, which contributed to improving beta-cell viability. In conclusion, GRP extract containing glycyrrhetinic acid improved glucose tolerance better than GR extract by enhancing insulinotropic action. Thus, GRP had better anti-diabetic action than GR. 相似文献
163.
Karawita R Senevirathne M Athukorala Y Affan A Lee YJ Kim SK Lee JB Jeon YJ 《Marine biotechnology (New York, N.Y.)》2007,9(4):479-490
The enzymatic extracts from seven species of microalgae (Pediastrum duplex, Dactylococcopsis fascicularis, Halochlorococcum porphyrae, Oltmannsiellopsis unicellularis, Achnanthes
longipes, Navicula sp. and Amphora coffeaeformis) collected from three habitats (freshwater, tidal pool, and coastal benthic) at Jeju Island in Korea were investigated for
their antioxidant activity. Of the extracts tested, the AMG 300 L (an exo 1, 4-α-d-glucosidase) extract of P. duplex, the Viscozyme extract of Navicula sp., and the Celluclast extract of A. longipes provided the most potential as antioxidants. Meanwhile, the Termamyl extract of P. duplex in an H2O2 scavenging assay exhibited an approximate 60% scavenging effect. In this study, we report that the DNA damage inhibitory
effects of P. duplex (Termamyl extract) and D. fascicularis (Kojizyme extract) were nearly 80% and 69% respectively at a concentration of 100 μg/ml. Thus, it is suggested that the microalgae
tested in this study yield promising DNA damage inhibitory properties on mouse lymphoma L 5178 cells that are treated with
H2O2. Therefore, microalgae such as P. duplex may be an excellent source of naturally occurring antioxidant compounds with potent DNA damage inhibition potential. 相似文献
164.
Complete sequence of the mitochondrial genome of Taenia saginata: comparison with T. solium and T. asiatica 总被引:1,自引:0,他引:1
The complete sequence of the Taenia saginata mitochondrial genome was determined, and its organization and structure were compared to other human-tropic Taenia tapeworms for which complete mitochondrial sequence data were available. The mitochondrial genome was 13,670 bp long, contained 12 protein-coding genes, two ribosomal RNAs (rRNAs, a small and a large subunit), and 22 transfer RNAs (tRNAs). It did not encode the atp8 gene. Overlapping regions were found between nad4L and nad4, nad1 and trnN, and cox1 and trnT. The ATG initiation codon was used for 10 protein-coding genes, and the GTG initiation codon was used for the remaining 2 genes (nad4 and atp6). The size of the protein-coding genes of the three human Taenia tapeworms did not vary, except for Taenia solium nad1 (891 aa) and nad4 (1212 aa) and Taenia asiatica cox2 (576 aa). The tRNA genes were 57-75 bp long, and the predicted secondary structures of 18 of these genes had typical clover-leaf shapes with paired dihydrouridine (DHU) arms. The genes in all human Taenia tapeworms for the two mitochondrial rRNA subunits rrnL and rrnS are separated by trnC. The putative T. saginata rrnL and rrnS are 972 and 732 bp long, respectively. The non-coding regions of the mt genome of T. saginata consisted of 2 regions: a short non-coding region (SNR, 66 nucleotides) and a long non-coding region (LNR, 159 nucleotides). The overall sequence difference in the full mitochondrial genome between T. saginata and T. asiatica was 4.6%, while T. solium differed by 11%. In conclusion, the complete sequence of the T. saginata mitochondrial genome will serve as a resource for comparative mitochondrial genomics and systematic studies of the parasitic cestodes. 相似文献
165.
166.
167.
A nuclear‐encoded chloroplast‐targeted S1 RNA‐binding domain protein affects chloroplast rRNA processing and is crucial for the normal growth of Arabidopsis thaliana 下载免费PDF全文
168.
Live cell imaging compatible immobilization of Chlamydomonas reinhardtii in microfluidic platform for biodiesel research 下载免费PDF全文
169.
Enhancing functional expression of heterologous proteins through random substitution of genetic codes in the 5' coding region 下载免费PDF全文
170.
Minseon Park Bok-Soon Lee Soung-Hoo Jeon Hyun-Ja Nam Gwang Lee Chul-Ho Kim Hyeseong Cho Jae-Ho Lee 《The Journal of biological chemistry》2015,290(3):1804-1817
Hepatocyte growth factor (HGF) and its receptor, Met, regulate skeletal muscle differentiation. In the present study, we identified a novel alternatively spliced isoform of Met lacking exon 13 (designated Δ13Met), which is expressed mainly in human skeletal muscle. Alternative splicing yielded a truncated Met having extracellular domain only, suggesting an inhibitory role. Indeed, Δ13Met expression led to a decrease in HGF-induced tyrosine phosphorylation of Met and ERK phosphorylation, as well as cell proliferation and migration via sequestration of HGF. Interestingly, in human primary myoblasts undergoing differentiation, Δ13Met mRNA and protein levels were rapidly increased, concomitantly with a decrease in wild type Met mRNA and protein. Inhibition of Δ13Met with siRNA led to a decreased differentiation, whereas its overexpression potentiated differentiation of human primary myoblasts. Furthermore, in notexin-induced mouse injury model, exogenous Δ13Met expression enhanced regeneration of skeletal muscle, further confirming a stimulatory role of the isoform in muscle cell differentiation. In summary, we identified a novel alternatively spliced inhibitory isoform of Met that stimulates muscle cell differentiation, which confers a new means to control muscle differentiation and/or regeneration. 相似文献