[Show abstract][Hide abstract] ABSTRACT: Acrolein is an alpha, beta-unsaturated aldehyde present in cigarette smoke, and is also a product of lipid peroxidation. Heme
oxygenase-1 (HO-1) plays critical roles in preventing oxidative stress and other cellular functions, and induces viability
and proliferation of tumor cells. Acrolein is well-known to induce HO-1, although the signal pathway has not been fully elucidated.
This study elucidated the involved signaling and acrolein’s cytoprotective effects in human hepatocellular carcinoma (HepG2)
cells. Cells were treated with acrolein to induce HO-1, whose expression was measured by Western blot, RT-PCR and immunofluorescence
staining analyses. Low concentrations of acrolein remarkably increased HO-1 mRNA and protein levels. Acrolein-mediated HO-1
induction was notably decreased by rottlerin and SB203580, selective inhibitors of PKC-δ and p38 MAPK, respectively. Furthermore,
the cells displayed an increased arrest at the G0/G1 phase of the cell-cycle. The data indicates that acrolein enhances HO-1 expression via PKC-δ and p38 MAPK signaling. Acrolein
may provide a cytoprotective effect via the expression of HO-1 in HepG2 cells.
KeywordsAcrolein-Heme oxygenase-1-Human hepatocellular carcinoma-Cytoprotective
[Show abstract][Hide abstract] ABSTRACT: Uncaria rhynchophylla (UR) is an herbal plant that has been used widely to treat stroke, hypertension and atherosclerosis. Upregulated heme oxygenase-1
(HO-1) plays a crucial role in cytoprotection and anti-inflammatory responses in a variety of pathological models. In this
study, we investigated upregulation of HO-1 by UR, which is inducible and cytoprotective enzyme in RAW 264.7 macrophages.
Upregulation of HO-1 and signal pathways were examined by western blots, RT-PCR and immunofluorescence staining. Treatment
of UR induced HO-1 protein expression and Nrf2 nuclear translocation in RAW 264.7 macrophages. HO-1 induction was strongly
inhibited by the suppression of p38 MAPK and ERK activity. Additionally, rottlerin, an inhibitor of protein kinase C δ (PKC
δ), abolished the upregulation of HO-1 protein levels. From the above results, it is suggested that UR may exert a cytoprotective
effect via the upregulation of HO-1 in RAW 264.7 macrophages.
-Heme oxygenase 1-Macrophage-Nrf2
[Show abstract][Hide abstract] ABSTRACT: Give me some feedback: In vitro selection of aptamers against the H3 peptide provided specific hairpin RNAs that possess high homology with histone H3 mRNA. The identified H3 hairpin RNA binds specifically to the H3 peptide with micromolar affinity and dose-dependently inhibits in vitro translation of the H3 protein. Consequently, the hairpin RNA and H3 peptide are one of the rare cis- and trans-elements on coding regions found among housekeeping proteins in higher eukaryotes.
[Show abstract][Hide abstract] ABSTRACT: Primary liposarcoma of the liver is extremely rare. We report here on a case of primary well-differentiated liposarcoma in the left hepatic lobe of a 63-year-old woman. Abdominal ultrasonography showed a well-defined, echogenic, round mass. Abdominal computed tomography (CT) and magnetic resonance (MR) images showed an almost fatty, lobulated mass with a few, random distributed vascular structures and a small area of nodular enhancement. The resected tumor appeared as a well-defined, round, tan-yellow mass. Histological analysis showed a well-differentiated liposarcoma.
[Show abstract][Hide abstract] ABSTRACT: The combinatorial introduction of N,N-dimethyl-Lys groups into Lys-rich α-helical peptides and measuring affinities against RRE RNA were carried out. Peptide-g, in which two Lys were replaced by N,N-dimethyl-Lys at 3 and 9 positions, showed low-nanomolar affinity, which is almost the same value as Rev peptide, the natural RRE ligand. Moreover, peptide-g displays a compatible binding specificity as Rev peptide. The effects of the positions of Lys N,N-dimethylation on the specificity of RNA binding could serve as the basis of a new strategy for the design of novel agents against RNAs. The results support that nature may use N-methylation as a post-translational modification to enhance specific peptide−RNA interactions.
Journal of the American Chemical Society 05/2007; 129(15):4514-5. DOI:10.1021/ja068265m · 12.11 Impact Factor