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.

Preparation and in vitro Physical Activities of Crude Natural Surfactant and Artificial Pulmonary Surfactant Containing Synthetic Peptide and Phospholipid Mixtures

PURPOSE: In this study, natural pulmonary surfactant was extracted from bovine lung lavage and its surface activity was determined. To investigate the usefulness of synthetic peptides reconstituted with phospholipid as artificial surfactant, truncated peptides from surfactant protein (SP)-B were synthesized and restored the surface tension lowering activities when appropriately recombined with phospholipid. METHODS: Crude natural surfactant (CNS) was isolated from lung lavage by centrifugation and organic solvent for the extraction of pulmonary surfactant was selected to satisfy the in vitro physical properties. Two truncated peptides derived from C-terminal end of bovine SP-B hydrophobic protein were selected and synthesized. To prepare artificial surfactant, synthetic peptides was added to the phospholipid mixture. The various surfactant mixtures were assayed for in vitro physical activity with the Wilhemly plate method and were determined by surface spreading rate, surface adsorption rate and surface tension-area diagram. RESULTS: CNS-chloroform methanol (CM) displayed efficient surface activity compared with clinically used Surfacten but CNS-BuOH did not. The artificial surfactants containing phospholipid mixture and synthetic peptide were analyzed for their surface activities and displayed significant surfactant properties. CONCLUSION: 1-Butanol or CM (3:1) was used as an extraction solvent for CNS. CNS-CM showed more efficient surface activity than CNS-BuOH. Two synthetic peptides composing artificial pulmonary surfactant were designed and mixing ratio of peptide and phospholipid was established. Artificial surfactant dispalyed weaker surface activity than natural surfactant but significant surfactant activity.

Evaluation of Differential Antigenic Properties of Selected B - cell Epitopes from the HIV - 1 p24 Protein using Synthetic Peptides / 대한면역학회지

The gag encoded p24 protein of human immunodeficiency virus-1 (HIV-1) is a major constitutent of the viral core, and is also known as one of the most immunodominant antigens in the host immune response against the HIV-1. Based on the neutralizing ability of anti-p24 antibodies as well as their rapid appearance in human serum after viral infection, the development of vaccines and diagnostic tools targeting the p24 protein and anti-p24 antibodies is of great interest. For the characterization of the immunological properties of the HIV-1 p24 protein, in a previous study, putative B-cell epitopes were identified by screening the reactivity of a goat anti-p24 antiserum to a large array of overlapping synthetic peptides covering the whole p24 sequence. Four peptides were identified for their abilities to elicit a strong B-cell response, which sequences comprises the regions p24 (164-182), (202-221), (217-236) and (232-256), respectively. In the present study, the immunogenicity and differential properties of each of these individual epitopes were further characterized. To evaluate the time course of the antibody response, BALB/c mice were immunized with the HIV-1 p24 protein and their serum titers against each of these peptides were determined. The earliest immune response was observed against the p24 (202-221) peptide, which also showed the highest antibody titer against the immunized antigen. Furthermore,. enzyme-linked immunosorbent assay with HIV-1 p24 protein coated microtiter plates revealed that anti-p24 (202-221) antiserum has the most pronounced reactivity against the native p24 protein. Since the p24 (202-221) epitope has also been reported to include a cytotoxic T-lymphocyte epitope, it is suggested that this region might represent a powerful antigenic site responsible for eliciting both T- and B-cell immune response. The possible application of this specific epitope in vaccine development or AIDS diagnosis is discussed.

Epitope Mapping of HIV1 gp41 Protein for Korean Anti - HIV1 Antisera using Synthetic Peptides / 대한면역학회지

The N-terminal sequence of HIV1 gp41 (amino acid residues 584-623) was known to be the immundominant region of HIV1 gp41 protein. In order to determine epitope for gp41 protein of Korean anti-HIV1 positive sera, multiple antigenic peptides (MAPs) for the sequences corresponding to 584-604, 590-612, 604-623 and 584-618 of HIV1 gp41 were synthesized by solid phase method using Fmoc-Lys (Fmoc)-OH and used as coating antigens for ELISA. The reactivities of the synthetic peptides with Korean HIV1 positive (21 samples) and anti-HIV1 negative sera (22 samples) obtained from healthy blood doner were estimated by an indirect ELISA. MAPs for 584-604, 590-612 and 604-623 of gp41 reacted with 62 %, 100 % and 81 % of Korean anti-HIV1 positive sera tested, respectively. The results suggest that the epitope for HIV1 gp 41 for Korean anti-HIV1 positive sera is located in the region of amino acid 590-612 of gp41. MAP for gp41 (584-618) reacted with all (100 %) of anti-HIV1 positive sera tested, but did not react with anti-HlV1 negative sera. In addition, this MAP reacted stronger with seven samples of anti-HIV1 positive sera of anti-HIV1/2 combo performance panel than the mixture of 584-604, 590-612 and 604-623 of gp41, but did not react with anti-HIV negative serum. The high sensitivity and selectivity of MAP of gp41 (584-618) suggest that this peptide as a coating antigen in an ELISA system will be useful for antibody detection of HIV1.