Magnolol Inhibits LPS-induced NF-kappaB/Rel Activation by Blocking p38 Kinase in Murine Macrophages

This study demonstrates the ability of magnolol, a hydroxylated biphenyl compound isolated from Magnolia officinalis, to inhibit LPS-induced expression of iNOS gene and activation of NF-kappaB/Rel in RAW 264.7 cells. Immunohisto-chemical staining of iNOS and Western blot analysis showed magnolol to inhibit iNOS gene expression. Reporter gene assay and electrophoretic mobility shift assay showed that magnolol inhibited NF-kappaB/Rel transcriptional activation and DNA binding, respectively. Since p38 is important in the regulation of iNOS gene expression, we investigated the possibility that magnolol to target p38 for its anti-inflammatory effects. A molecular modeling study proposed a binding position for magnolol that targets the ATP binding site of p38 kinase (3GC7). Direct interaction of magnolol and p38 was further confirmed by pull down assay using magnolol conjugated to Sepharose 4B beads. The specific p38 inhibitor SB203580 abrogated the LPS-induced NF-kappaB/Rel activation, whereas the selective MEK-1 inhibitor PD98059 did not affect the NF-kappaB/Rel. Collectively, the results of the series of experiments indicate that magnolol inhibits iNOS gene expression by blocking NF-kappaB/Rel and p38 kinase signaling.

5-Lipoxygenase Promotor Polymorphism in Nasal Polyp Patients / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Nasal polyps are the most common mass lesions in the nasal cavity and occur on both infectious and noninfectious basis, and genetic etiology is suspected in the development of nasal polyps. 5-Lipoxygenase is the first enzyme committed in the metabolic pathway leading to the intracellular synthesis of leukotrienes. Some studies have shown that leukotrienes were significantly higher in nasal polyps from aspirin-sensitive asthmatics than in nasal polyps from aspirin-tolerant asthmatics and normal nasal mucosa. The purpose of the present study is to evaluate whether genetic polymorphism of the core promoter region of the 5-lipoxygenase gene contributes to the development of nasal polyps. SUBJECTS AND METHOD: This study was conducted in 97 nasal polyp patients associated with chronic sinusitis and 92 healthy controls. Genetic polymorphisms of 5-lipoxygenase gene promoter were genotyped by PCR and direct sequencing. RESULTS: There were no significant differences between the 5-lipoxygenase gene promoter polymorphisms in nasal polyp patients with chronic sinusitis and those in healthy controls (p=0.76). In the nasal polyp patients associated with chronic sinusitis, the frequencies of 6-bp deletion were lower than those of healthy controls (OR, 0.88 95% CI, 0.48-1.60), but there was no statistical significance (p=0.67). The frequencies of 6-bp addition were higher than those of healthy controls (OR, 1.96; 95% CI, 0.33-10.6), but no significant difference was found (p=0.68). CONCLUSION: We concluded that 5-lipoxygenase gene promoter polymorphism did not show genetic predisposition with regard to nasal polyps in the Korean population.

Kinesin Superfamily KIF1Balpha Protein Binds to the PDZ Domain of MALS-3 / 대한해부학회지

The Kinesin superfamily proteins (KIFs) make up a large superfamily of molecular motors that transport cargo such as vesicles, protein complexes, and organelles. KIF1Balpha is a monomeric motor that conveys mitochondria and plays an important role in cellular function. Here, we used the yeast two-hybrid system to identify the proteins that interacts with KIF1Balpha and found a specific interaction with the mammalian LIN-7 (MALS)-3/vertebrate homology of LIN-7 (Veri) and synaptic scaffolding molecule (S-SCAM). MALS-3 protein bound to the tail region of KIF1Balpha but not to other kinesin family members in the yeast two-hybrid assay. The "T-X-V" motif at the C-terminal end of KIF1Balpha is essential for interaction with MALS-3. In addition, this protein showed specific interactions in the Glutathione S-transferase (GST) pull-down assay. An antibody to MALS-3 specifically coimmunoprecipitated KIF1Balpha associated with MALS-3 from mouse brain extracts. These results suggest that MALS-3, as KIF1Balpha receptor, is involved in the KIF1Balpha-mediated transport.

Kinesin Superfamily KIF1A Protein Binds to Synaptotagmin XI / 대한해부학회지

The kinesin proteins (KIFs) make up a large superfamily of molecular motors that transport cargo such as vesicles, protein complexes, and organelles. KIF1A is a monomeric motor that conveys synaptic vesicle precursors and plays an important role in neuronal function. Here, we used the yeast two-hybrid system to identify the neuronal protein (s) that interacts with the tail region of KIF1A and found a specific interaction with synaptotagmin XI. The amino acid residues between 830 and 1300 of KIF1A are required for the interaction with synaptotagmin XI. KIF1A also bound to the tail region of synaptotagmin IV but not to other synaptotagmin in the yeast two-hybrid assay. KIF1A interacted with GST-synaptotagim XI fusion proteins, but not with GST alone. An antibody to synaptotagmin XI specifically co-mmunoprecipitated KIF1A associated with synaptotagimin from mouse brain extracts. These results suggest that KIF1A motor protein transports of synaptotagmin XI-containing synaptic vesicle precursors along microtubule.

Kinesin Superfamily KIF5 Proteins Bind to betaIII Spectrin

The kinesin proteins (KIFs) make up a large superfamily of molecular motors that transport cargo such as vesicles, protein complexes, and organelles. KIF5 is a heterotetrameric motor that conveys vesicles and plays an important role in neuronal function. Here, we used the yeast two-hybrid system to identify the neuronal protein (s) that interacts with the tail region of KIF5 and found a specific interaction with betaIII spectrin. The amino acid residues between 1394 and 1774 of betaIII spectrin were required for the interaction with KIF5C. betaIII spectrin also bound to the tail region of neuronal KIF5A and ubiquitous KIF5B but not to other kinesin family members in the yeast two-hybrid assay. In addition, these proteins showed specific interactions, confirmed by GST pull-down assay and co-immunoprecipitation. betaIII spectrin interacted with GST-KIF5 fusion proteins, but not with GST alone. An antibody to betaIII spectrin specifically co-immunoprecipitated KIF5s associated with betaIII spectrin from mouse brain extracts. These results suggest that KIF5 motor proteins transport vesicles or organelles that are coated with betaIII spectrin.

Clinicopathologic Significance of HBV X, Core promoter, Precore Mutants in Patients with Chronic HBV Infection / 대한간학회지

BACKGROUND/AIMS: There have been much debates on the effects of HBV mutants on the clinical course of HBV-associated chronic liver diseases. The purpose of this study was to define the relationship among HBV mutants, severity of hepatitis and expression patterns of HBcAg METHODS: HBV DNA was extracted from the liver tissue of 31 patients who had been HBsAg positive for more than 6 months. The amplification of X was performed as well as core promoter/precore region of HBV DNA by polymerase chain reaction and then direct sequencing of them. Pathologic severity was classified utilizing Scheuer's scoring system and immunohistochemical staing for HBcAg in hepatocytes was performed. The expression patterns of HBcAg were divided into four types according to expression location of HBcAg: Type I as a nuclear predominant expression of HBcAg; Type II as mixed patterns, combined expression of cytoplasmic and nuclear localization of HBcAg; Type III as a diffuse cytoplasmic expression of HBcAg; and Type II as an inclusive body-like expression in cytoplasm. RESULTS: In investigating the relationship between HBV mutants and clinical findings, ALT, HBV DNA and hepatitis activity index (HAI) in hepatitis with wild HBV were normal to high but those in hepatitis with core promoter or precore mutants were high . There were no statistically significant differences (p=0.062). In terms of the relationship between HBV mutants and the expression pattern of HBcAg, type I, II, IV were noticed in hepatitis with wild HBV but in almost all mutants cases type III, II were noticed (p<0.01). The score of HAI increased as the number of the expression pattern of HBcAg increased from type I to type III or IV(p<0.05). No relationships among the mutation in X region, the mutations in other regions and clinicopathological severity could be found. CONCLUSION: The mutation in X, core promoter and precore region had little association with the severity of hepatitis. And the relationship did not exist between precore mutants and X mutants. The expression pattern of HBcAg could be a useful indicator in determining what stage of chronic hepatitis B is in and whether mutant strains exist.