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91.
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Jin Sil Chung Seung Baek Lee Seon Ho Park Sung Tae Kang Ah Ram Na Tong-Shin Chang 《Free radical research》2013,47(8):729-737
Reactive oxygen species (ROS) steady-state levels are required for entry into the S phase of the cell cycle in normal cells, as well as in tumour cells. However, the contribution of mitochondrial ROS to normal cell proliferation has not been well investigated thus far. A previous report showed that Romo1 was responsible for the high ROS levels in tumour cells. Here, we show that endogenous ROS generated by Romo1 are indispensable for cell cycle transition from G1 to S phase in normal WI-38 human lung fibroblasts. The ROS level in these cells was down-regulated by Romo1 knockdown, resulting in cell cycle arrest in the G1 phase. This arrest was associated with an increase in the level of p27Kip1. These results demonstrate that mitochondrial ROS generated by Romo1 expression is required for normal cell proliferation and it is suggested that Romo1 plays an important role in redox signalling during normal cell proliferation. 相似文献
94.
Su-Min Lee Sin Young Park Seoung Woo Shin In Sup Kil Eun Sun Yang 《Free radical research》2013,47(2):165-173
Staurosporine induces the production of reactive oxygen species, which play an important causative role in apoptotic cell death. Recently, it was demonstrated that the control of cellular redox balance and the defense against oxidative damage is one of the primary functions of cytosolic NADP+-dependent isocitrate dehydrogenase (IDPc) by supplying NADPH for antioxidant systems. The present report shows that silencing of IDPc expression in HeLa cells greatly enhances apoptosis induced by staurosporine. Transfection of HeLa cells with an IDPc small interfering RNA (siRNA) markedly decreased activity of IDPc, enhancing the susceptibility of staurosporine-induced apoptosis reflected by DNA fragmentation, cellular redox status and the modulation of apoptotic marker proteins. These results indicate that IDPc may play an important role in regulating the apoptosis induced by staurosporine and the sensitizing effect of IDPc siRNA on the apoptotic cell death of HeLa cells offers the possibility of developing a modifier of cancer chemotherapy. 相似文献
95.
Byoung-Shik Shim Jung-ah Choi Ho-Hyun Song Sung-Moo Park In Su Cheon Ji-Eun Jang Sun Je Woo Chung Hwan Cho Min-Suk Song Hyemi Kim Kyung Joo Song Jae Myun Lee Suhng Wook Kim Dae Sub Song Young Ki Choi Jae-Ouk Kim Huan Huu Nguyen Dong Wook Kim Young Yil Bahk Cheol-Heui Yun Man Ki Song 《Journal of microbiology (Seoul, Korea)》2013,51(1):130-135
Influenza viruses are respiratory pathogens that continue to pose a significantly high risk of morbidity and mortality of humans worldwide. Vaccination is one of the most effective strategies for minimizing damages by influenza outbreaks. In addition, rapid development and production of efficient vaccine with convenient administration is required in case of influenza pandemic. In this study, we generated recombinant influenza virus hemagglutinin protein 1 (sHA1) of 2009 pandemic influenza virus as a vaccine candidate using a well-established bacterial expression system and administered it into mice via sublingual (s.l.) route. We found that s.l. immunization with the recombinant sHA1 plus cholera toxin (CT) induced mucosal antibodies as well as systemic antibodies including neutralizing Abs and provided complete protection against infection with pandemic influenza virus A/CA/04/09 (H1N1) in mice. Indeed, the protection efficacy was comparable with that induced by intramuscular (i.m.) immunization route utilized as general administration route of influenza vaccine. These results suggest that s.l. vaccination with the recombinant non-glycosylated HA1 protein offers an alternative strategy to control influenza outbreaks including pandemics. 相似文献
96.
Yochan Joung Haneul Kim Beom-Il Lee Heeyoung Kang Tae Yong Jang O-Seob Kwon Kiseong Joh 《Journal of microbiology (Seoul, Korea)》2013,51(4):531-535
A Gram-staining-negative, rod-shaped and red-pigmented bacterial strain, HMD3125T, was isolated from a solar saltern in Jeungdo, Republic of Korea. A phylogenetic tree based on 16S rRNA gene sequences showed that strain HMD3125T formed a lineage within the genus Pontibacter and was similar to Pontibacter salisaro (96.1%) and P. korlensis (95.3%). The major fatty acids of strain HMD3125T were summed feature 4 (comprising iso-C17:1 I and/or anteiso-C17:1 B; 30.4%), iso-C15:0 (20.4%) and iso-C17:0 3OH (17.2%). The polar lipid profile of HMD3125T consisted of the phosphatidylethanolamine, four unidentified polar lipids, unidentified phospholipid, unidentified aminolipid and unidentified aminophospholipid. Strain HMD3125T contained MK-7 as the predominant menaquinone and sym-homospermidine as the major polyamine. The DNA G+C content of strain HMD3125T was 45.6 mol%. Strain HMD3125T assigned as a novel species in the genus Pontibacter, for which the name Pontibacter jeungdoensis sp. nov. is proposed. The type strain is HMD3125T (=KCTC 23156T =CECT 7710T). 相似文献
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98.
Changon Seo Yun-Hyeok Choi Jong Seog Ahn Joung Han Yim Hong Kum Lee 《Journal of enzyme inhibition and medicinal chemistry》2013,28(5):1133-1137
The selective inhibition of PTP1B has been widely recognized as a potential drug target for the treatment of type 2 diabetes and obesity. In the course of screening for PTP1B inhibitory natural products, the MeOH extract of the dried sample of the Antarctic lichen Umbilicaria antarctica was found to exhibit significant inhibitory effect, and the bioassay-guided fractionation and purification afforded three related lichen metabolites 1-3. Compounds 1-3 were identified as gyrophoric acid (1), lecanoric acid (2), and methyl orsellinate (3) mainly by analysis of NMR and MS data. These compounds inhibited PTP1B activity with 50% inhibitory concentration values of 3.6 ± 0.04 μM, 31 ± 2.7 μM, and 277 ± 8.6 μM, respectively. Furthermore, the kinetic analysis of PTP1B inhibition by compound 1 suggested that the compound inhibited PTP1B activity in a non-competitive manner. 相似文献
99.
Ahmed K. Farag Ahmed H. E. Hassan Byung Sun Ahn Ki Duk Park 《Journal of enzyme inhibition and medicinal chemistry》2013,28(1):311-324
Abstract Hybridization of reported weakly active antiproliferative hit 5-amino-4-pyrimidinol derivative with 2-anilino-4-phenoxypyrimidines suggests a series of 2,5-diamino-4-pyrimidinol derivatives as potential antiproliferative agents. Few compounds belonging to the proposed series were reported as CSF1R/DAPK1 inhibitors as anti-tauopathies. However, the correlation between CSF1R/DAPK1 signalling pathways and cancer progression provides motives to reprofile them against cancer therapy. The compounds were synthesised, characterized, and evaluated against M-NFS-60 cells and a kinase panel which bolstered predictions of their antiproliferative activity and suggested the involvement of diverse molecular targets. Compound 6e, the most potent in the series, showed prominent broad-spectrum antiproliferative activity inhibiting the growth of hematological, NSCLC, colon, CNS, melanoma, ovarian, renal, prostate and breast cancers by 84.1, 52.79, 72.15, 66.34, 66.48, 51.55, 55.95, 61.85, and 60.87%, respectively. Additionally, it elicited an IC50 value of 1.97?µM against M-NFS-60 cells and good GIT absorption with Pe value of 19.0?±?1.1?×?10?6?cm/s (PAMPA-GIT). Molecular docking study for 6e with CSF1R and DAPK1 was done to help to understand the binding mode with both kinases. Collectively, compound 6e could be a potential lead compound for further development of anticancer therapies. 相似文献
100.
Jun-Young Ahn Joon-Yeop Lee Eun-Ju Yang Young-Jin Lee Kyung-Bon Koo Kyung-Sik Song Kyeong-Yeoll Lee 《Journal of Asia》2013,16(3):317-320
Two anthraquinones were isolated from the symbiotic bacteria Photorhabdus temperata of entomopathogenic nematodes Heterorhabditis spp. by repeated column chromatography. They were abundantly present in the culture medium and identified as 1,3-dimethoxy-8-hydroxy-9,10-anthraquinone and 3-methoxychrysazine by spectral analysis. The isolated anthraquinones were highly lethal to larvae of Culex pipiens pallens. Our results suggest that anthraquinones might be useful as biopesticides for the biological control of mosquitoes. 相似文献