Involvement of the CXC Chemokines Mig and IP-10 in Response to M. bovis BCG in Mice

Seong-Tshool Hong,Jung Gil Cho,Hwang-Ho Lee 大韓微生物學會 2000 大韓微生物學會誌 Vol.35 No.2

HtrA2 Interacts with Aβ Peptide but Does Not Directly Alter Its Production or Degradation

Seong-Tshool Hong,Meng-Lu Liu,Ming-Jie Liu,Jin-Man Kim,Hyeon-Jin Kim,Jeong-Hak Kim 한국분자세포생물학회 2005 Molecules and cells Vol.20 No.1

HtrA2/Omi is a mammalian mitochondrial serine protease homologous to the E. coli HtrA/DegP gene products. Recently, HtrA2/Omi was found to have a dual role in mammalian cells, acting as an apoptosisinducing protein and being involved in maintenance of mitochondrial homeostasis. By screening a human brain cDNA library with Aβ peptide as bait in a yeast two-hybrid system, we identified HtrA2/Omi as a binding partner of β peptide. The interaction between Aβ peptide and HtrA2/Omi was confirmed by an immunoblot binding assay. The possible involvement of HtrA2/Omi in Aβ peptide metabolism was investigated. In vitro peptide cleavage assays showed that HtrA2/Omi did not directly promote the production of Aβ peptide at the β/γ-secretase level, or the degradation of Aβ peptide. However, overexpression of HtrA2/Omi in K269 cells decreased the production of Aβ40 and Aβ42 by up to 30%. These results rule out the involvement of HtrA2/Omi in the etiology of Alzheimer’s disease. However, the fact that overexpression of HtrA2/Omi reduces the generation of Aβ40 and Aβ42 suggests that it may play some positive role in mammalian cells.

Choline - Lipid Release from Normal and Transformed Cells

Hong, Seong Tshool,Jang, Yong Suk,Park, Kie In 생화학분자생물학회 1980 BMB Reports Vol.29 No.1

The effect of albumin on phosphatidylcholine (PC) metabolism in Hep-G2, 3T3-H.ras, and 3T3 cells pre-labelled with [Me ³H]choline was studied. The [³H]choline was more efficiently taken up and incorporated into cellular phospholipids in 3T3-H.ras cells than in Hep-G2 and 3T3 cells. In each of the three cell lines, most of the [³H]choline metabolized into the phospholipids was incorporated into PC and only minor was incorporated into lysophosphatidylcholine (LPC). Bovine serum albumin stimulated the release of [³H]LPC and [³H]PC from each of the three cell lines pre-labelled with [³H]choline. [³H]PC was also released in the absence of albumin but [³H]LPC was not. The efficiency of LPC secretion represented as the proportion of medium [³H]LPC to cellular [³H]choline lipid during a chase period is approximately 9 to 14 times greater in 3T3 cells compared with the transformed 3T3-H.ras and Hep-G2 cells. A similar comparison of published data for rat hepatocytes with Hep-G2 shows secretion to be 35∼75 times greater from the rat hepatocytes than from Hep-G2. Also, PC secretion from 3T3 cells was 1.6 times more effective than from 3T3-H.ras, whereas rat hepatocytes secrete PC 2.8∼3.8 times more effectively than does Hep-G2. The measurement of specific radioactivity of cellular PC in pre-labelled 3T3 cells showed it to be similar to that of the secreted PC. However, the specific radioactivity of secreted LPC was markedly lower than that of the cellular PC, which suggests that LPC is being secreted from a PC pool distinct from that used for PC secretion.

Involvement of the CXC Chemokines Mig and IP-10 in Response to M. bovis BCG in Mice

Hong, Seong-Tshool,Cho, Jung-Gil,Lee, Hwang-Ho The Korea Society for Microbiology 2000 大韓微生物學會誌 Vol.35 No.2

The non-ELR-containing CXC chemokines Mig and IP-10 have been shown to function as chemotactic cytokines for activated T lymphocytes. In this study, we examined the potential involvement of Mig and IP-10 in antimycobacterial response of mice immunized or infected with M. bovis BCG. The accumulation of Mig and IP-10 mRNA in resident peritoneal monocytes ($RPM{\Phi}$) was slightly reduced by stimulation with vBCG, and the degree was greater for 24 hr culture even though IFN-${\gamma}$ was added. Expression of Mig, IP-10, and IFN-${\gamma}$ in 24 hr delayed-type hypersensitivity (DTH) response was stronger in vBCG-immune mice than in the non-immune. The increase of DTH measured by foot-pad thickness appears to be clearly related to the levels of chemokines Mig and IP10 messages and those of IFN-${\gamma}$ and IL-12. Stimulation with vBCG for 2 days decreased or completely dropped the levels of Mig message in non-immune or immune splenocytes, respectively, whereas IP-10 message was slightly decreased in 2 days culture. Moreover, messages for IL-12 (p40) showed similar kinetics for Mig. The levels of Mig and IP-10 mRNA during the course of infection with BCG were not readily changed in lungs, livers, and spleens from BCG-infected mice. Although there was no obvious changes of Mig and IP-10 messages in the target organs during infection process, we found that the infection progressed over the first 3 wk before being contained by the emerging immune response suggested from detectable amount of IFN-${\gamma}$ mRNA around this time. In view of selectivity of chemokines Mig and IP-10 for activated T cells, these data suggest that chemokine Mig and IP-10, especially in collaboration with IL-12 and IFN-${\gamma}$, may playa role as T cell recruiters in immune response against mycobacterial infection.

Choline-Lipid Release from Normal and Transformed Cells

Hong, Seong-Tshool,Jang, Yong-Suk,Park, Kie-In Korean Society for Biochemistry and Molecular Biol 1996 Journal of biochemistry and molecular biology Vol.29 No.1

The effect of albumin on phosphatidylcholine (PC) metabolism in Hep-G2, 3T3-H.ras, and 3T3 cells pre-labelled with [Me-$^3H$]choline was studied. The [$^3H$]choline was more efficiently taken up and incorporated into cellular phospholipids in 3T3-H.ras cells than in Hep-G2 and 3T3 cells. In each of the three cell lines, most of the [$^3H$]choline metabolized into the phospholipids was incorporated into PC and only minor was incorporated into lysophosphatidylcholine (LPC). Bovine serum albumin stimulated the release of [$^3H$]LPC and [$^3H$]PC from each of the three cell lines pre-labelled with [$^3H$]choline. [$^3H$]PC was also released in the absence of albumin but [$^3H$]LPC was not. The efficiency of LPC secretion represented as the proportion of medium [$^3H$]LPC to cellular [$^3H$]choline lipid during a chase period is approximately 9 to 14 times greater in 3T3 cells compared with the transformed 3T3-H.ras and Hep-G2 cells. A similar comparison of published data for rat hepatocytes with Hep-G2 shows secretion to be 35~75 times greater from the rat hepatocytes than from Hep-G2. Also, PC secretion from 3T3 cells was 1.6 times more effective than from 3T3-H.ras, whereas rat hepatocytes secrete PC 2.8~3.8 times more effectively than does Hep-G2. The measurement of specific radioactivity of cellular PC in pre-labelled 3T3 cells showed it to be similar to that of the secreted PC. However, the specific radioactivity of secreted LPC was markedly lower than that of the cellular PC, which suggests that LPC is being secreted from a PC pool distinct from that used for PC secretion.

Acanthopanax and Platycodi Independently Prevents the Onset of High Fat Diet Induced Hyperglyceridemia and Obesity in C57BL/6 Mice

Sook-Jeong Shin,Seong-Tshool Hong 한국식품과학회 2005 Food Science and Biotechnology Vol.14 No.6

Non-Fibrillar $\beta$-Amyloid Exerts Toxic Effect on Neuronal Cells

Kim, Hyeon-Jin,Hong, Seong-Tshool The Korean Society for Integrative Biology 2001 Korean journal of biological sciences Vol.5 No.2

Alzheimer's disease is the most common form of dementia and no cure is known so far. Extensive genetic works and in vitro experiments combined with clinical observations link amyloid $\beta$--protein (A$\beta$-) to the pathogenesis of Alzheimer's disease (AD). It was hypothesized that $A\beta$- becomes toxic when it adopts a fibrillar conformation. Recently, non-fibrillar form of $A\beta$- was observed and the potential role in the pathogenesis of AD became an interesting subject. In this study, the cytotoxicity of non-fibrillar $A\beta$- and fibrillar $A\beta$- was compared on oxidative stress, membrane damage, or nucleosome break down. Non-fibrillar $A\beta$- was not toxic in peripheral nervous system-derived cells but significantly toxic in central nervous system-derived cells while fibrillar $A\beta$- was non-selectively toxic in both cell culture. The neurotoxicity of non-fibrillar $A\beta$- was reproduced in semi-in vivo culture of mouse brain slice. In conclusion, non-fibrillar $A\beta$- could be more relevant to the selective neurodegeneration in Alzheimer's brains than fibrillar $A\beta$- and further research needs to be done for identification of the cause of AD.

The role of gut microbiota in the gut-brain axis: current challenges and perspectives.

Chen, Xiao,D'Souza, Roshan,Hong, Seong-Tshool Springer ; Higher Education Press 2013 Protein & cell Vol.4 No.6

<P>Brain and the gastrointestinal (GI) tract are intimately connected to form a bidirectional neurohumoral communication system. The communication between gut and brain, knows as the gut-brain axis, is so well established that the functional status of gut is always related to the condition of brain. The researches on the gut-brain axis were traditionally focused on the psychological status affecting the function of the GI tract. However, recent evidences showed that gut microbiota communicates with the brain via the gut-brain axis to modulate brain development and behavioral phenotypes. These recent findings on the new role of gut microbiota in the gut-brain axis implicate that gut microbiota could associate with brain functions as well as neurological diseases via the gut-brain axis. To elucidate the role of gut microbiota in the gut-brain axis, precise identification of the composition of microbes constituting gut microbiota is an essential step. However, identification of microbes constituting gut microbiota has been the main technological challenge currently due to massive amount of intestinal microbes and the difficulties in culture of gut microbes. Current methods for identification of microbes constituting gut microbiota are dependent on omics analysis methods by using advanced high tech equipment. Here, we review the association of gut microbiota with the gut-brain axis, including the pros and cons of the current high throughput methods for identification of microbes constituting gut microbiota to elucidate the role of gut microbiota in the gut-brain axis.</P>

Immobilization of Ag3PO4 nanoparticles on electrospun PAN nanofibers via surface oximation: Bifunctional composite membrane with enhanced photocatalytic and antimicrobial activities

Gopal Panthi,박수진,채수형,김태우,정혜종,Seong-Tshool Hong,박미라,김학용 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.45 No.-

Ag3PO4/PAN composite nanofibers have been fabricated by simple and low cost electrospinningtechnique followed by surface modification of PAN nanofibers with amidoxime ( C(CN2)¼NOH) groupsto utilize as anchoring sites for Ag+ ions through coordinate bonding. Subsequently, the coordinated Ag+ions were allowed to react with PO43 ions in order to form Ag3PO4/PAN composite nanofibers. Thusobtained composites were characterized by FESEM, XRD, TEM, FTIR, XPS and UV–vis. Experimentalresults revealed that composite nanofibers prepared by reacting ( C(CN2)¼NOH) functionalized PANnanofibers with 0.02 M solutions of AgNO3 and Na2HPO4 have higher efficiency towards thephotodegradation and bactericidal activities under visible light.

A new method for transduction of mesenchymal stem cells using mechanical agitation

Park, Jin-O,Park, Sung-Hoon,Hong, Seong-Tshool Springer-Verlag 2009 Molecules and cells Vol.28 No.6

<P>Applications of bone marrow-derived mesenchymal stem cells in gene therapy have been hampered by the low efficiency of gene transfer to these cells. In current transduction protocols, retrovirus particles with foreign genes make only limited contact with their target cells by passive diffusion and have short life spans, thereby limiting the chances of viral infection. We theorized that mechanically agitating the virus-containing cell suspensions would increase the movement of viruses and target cells, resulting in increase of contact between them. Application of our mechanical agitation for transduction process has increased the absorption of retrovirus particles more than five times compared to the previous static method without changing cell growth rate and viability. The addition of a mechanical agitation step increased transduction efficiency to 42%, higher than that of any other previously-known static transduction protocol.</P>