• Clinical and Experimental Pediatrics
• /
• v.49 no.2
• /
• pp.198-202
• /
• 2006

Purpose : Fas is a cell surface receptor that transduces apoptotic death signals. Interaction of extracelluar domain of Fas with Fas ligand(FasL) triggers the apoptotic process in many diseases. We investigated the expression of Fas and FasL in the hippocampus of 7-day-old newborn rat brains following hypoxia-ischemia injury. Methods : The 7-days-old newborn rats were exposed to 8 percent oxygen for two hours after the ligation of right common carotid arteries. The newborn rats were killed and their brains were removed at 12, 14 and 48 hours after hypoxic-ischemic injury. The expressions of Fas and FasL of the right hippocampus were observed by western blotting and immunofluorescent staining. Results : Fas and FasL were strongly expressed in the right hippocampus ipsilateral to the ligation of the common carotid artery by western blotting at 12 hours following hypoxic-ischemic injury, and then slowly decreased. The immunofluorescent expressions of Fas and FasL strongly increased in the CA1 area of the right hippocampus at 12 and 24 hours following hypoxic-ischemic injury. The immunofluorescent expression of Fas decreased at 48 hours, but the expression of FasL persisted strongly at 48 hours following hypoxic-ischemic injury. Conclusion : The interaction of Fas with FasL on the cell surface may be involved in neuronal injury following hypoxic-ischemic injury in the developing brain.

• Journal of Microbiology and Biotechnology
• /
• v.25 no.10
• /
• pp.1751-1760
• /
• 2015

Mucin2 (MUC2), an important regulatory factor in the immune system, plays an important role in the host defense system against bacterial translocation. Probiotics known to regulate MUC2 gene expression have been widely studied, but the interactions among probiotic, pathogens, and mucin gene are still not fully understood. The aim of this study was to investigate the role of MUC2 in blocking effects of probiotics on meningitic E. coli-induced pathogenicities. In this study, live combined probiotic tablets containing living Bifidobacterium, Lactobacillus bulgaricus, and Streptococcus thermophilus were used. MUC2 expression was knocked down in Caco-2 cells by RNA interference. 5-Aza-2'-deoxycytidine (5-Aza-CdR), which enhances mucin-promoted probiotic effects through inducing production of Sadenosyl-L-methionine (SAMe), was used to up-regulate MUC2 expression in Caco-2 cells. The adhesion to and invasion of meningitic E. coli were detected by competition assays. Our studies showed that probiotic agents could block E. coli-caused intestinal colonization, bacteremia, and meningitis in a neonatal sepsis and meningitis rat model. MUC2 gene expression in the neonatal rats given probiotic agents was obviously higher than that of the infected and uninfected control groups without probiotic treatment. The prohibitive effects of probiotic agents on MUC2-knockdown Caco-2 cells infected with E44 were significantly reduced compared with nontransfected Caco-2 cells. Moreover, the results also showed that 5-Aza-CdR, a drug enhancing the production of SAMe that is a protective agent of probiotics, was able to significantly suppress adhesion and invasion of E44 to Caco-2 cells by upregulation of MUC2 expression. Taken together, our data suggest that probiotic agents can efficiently block meningitic E. coli-induced pathogenicities in a manner dependent on MUC2.

• Clinical and Experimental Pediatrics
• /
• v.52 no.12
• /
• pp.1337-1347
• /
• 2009

Purpose:Taurine (2-aminoethanesulfonic acid) is a simple sulfur-containing amino acid. It is abundantly present in tissues such as brain, retina, heart, and skeletal muscles. Current studies have demonstrated the neuroprotective effects of taurine, but limited data are available for such effects during neonatal period. The aim of this study was to determine whether taurine could reduce hypoxic-ischemic (HI) cerebral injury via anti-apoptosis mechanism. Methods:Embryonic cortical neurons isolated from Sprague-Dawley (SD) rats at 18 days gestation were cultured in vitro. The cells were divided into hypoxia group, taurine-treated group before hypoxic insult, and taurine-treated group after HI insult. In the in vivo model, left carotid artery ligation was performed in 7-day-old SD rat pups. The pups were exposed to hypoxia, administered an injection of 30 mg/kg of taurine, and killed at 1 day, 3 days, 1 week, 2 weeks, and 4 weeks after the hypoxic insult. We compared the expressions of Bcl-2, Bax, and caspase-3 among the 3 groups by using real- time polymerase chain reaction (PCR) and western blotting. Results:The cells in the taurine-treated group before hypoxic insult, although similar in appearance to those in the normoxia group, were lesser in number. In the taurine-treated group, Bcl-2 expression increased, whereas Bax and caspase-3 expressions reduced. Conclusion:Taurine exerts neuroprotective effects onperinatal HI brain injury due to its anti-apoptotic effect. The neuroprotective effect was maximal at 1-2 weeks after the hypoxic injury.

• Journal of Society of Preventive Korean Medicine
• /
• v.9 no.2
• /
• pp.59-75
• /
• 2005

The experiments were undertaken to evaluate the effects of Bosaengtang in pregnant rats and fetuses. Female Sprague-Dawley rats were orally administered with Bosaengtang at the dose of 5mg/kg/day for 20 days. Pregnant rats were sacrificed at the 20th day of gestation, and observed internal and reproductive organs. Fetuses were randomly selected and fixed in 95% ethanol. Fetuses were stained with alcian blue and alizarin red S, and observed skeletal malformations. The results obtained were as follows : Bosaengtang administered group showed higher maternal body weight than the control group, but both groups showed increase in weight. Bosaengtang administered group showed lower than the control group, and higher liver and kidney weight than the control group, but the differences were minimal. There were no significant changes between the control and treated group in blood chemistry values and hematological values but all the groups were within in normal ranges. There were no significant changes in the number of corpus luteum, implantation, live fetus and implantation rate, delivery rate, late resorption rate, sex ratio, but Bosaengtang administered group showed higher early resorption rate than control group. comparing the control and Bosaengtang group, neonatal body weight and the number of fetuses were increased in Bosaengtang group. The fetuses of dams treated with Oriental medicine didn't showed external malformation. Vertebral and sternal variations were observed in Bosaengtang group, but the differences were not apparent compared to the control group. The number of ribs, cervical, thoracic and lumbar vertebrae were normal. The number of sacral was similar and the number of caudal was increased. Fetuses showed significant difference in the number of caudal vertebrae. (P<0.01) From these results, we can carefully conclude that Bosaengtang showed beneficial effects on maternal body weight, early resorption rate, number of live fetus. There were no significant changes in organ weight, hematoscopy, reproduction organs. External malformation wasn't visible. Skeletal variations were showed in vertebrae and sternum but compared to the control group, these variations weren't much different.

• Clinical and Experimental Pediatrics
• /
• v.50 no.7
• /
• pp.686-693
• /
• 2007

Purpose : Mycophenolic acid (MPA), the active metabolite of mycophenolate mofetil (MMF), is a potent inhibitor of inosine-monophosphate dehydrogenase (IMPDH), a new immunosuppressive drug used. It was reported that MPA protected neurons after excitotoxic injury, induced apoptosis in microglial cells. However, the effects of MPA on hypoxic-ischemic (HI) brain injury has not been yet evaluated. Therefore, we examined whether MPA could be neuroprotective in perinatal HI brain injury using Rice-Vannucci model (in vivo) and in rat brain cortical cell culture induced by hypoxia (in vitro). Methods : Cortical cells were cultured using a 18-day-pregnant Sprague-Dawley (SD) rats and incubated in 1% $O_2$ incubator for hypoxia. MPA ($10{\mu}g/mL$) before or after a HI insult was treated. Seven-day-old SD rat pups were subjected to left carotid occlusion followed by 2 hours of hypoxic exposure (8% $O_2$). MPA (10 mg/kg) before or after a HI insult were administrated intraperitoneally. Apoptosis was measured using western blot and real-time PCR for Bcl-2, Bax, caspase-3. Results : H&E stain revealed increased brain volume in the MPA-treated group in vivo animal model of neonatal HI brain injury. Western blot and real-time PCR showed the expression of caspase-3 and Bax/Bcl-2 were decreased in the MPA-treated group In in vitro and in vivo model of perinatal HI brain injury, Conclusion : These results may suggest that the administration of MPA before HI insult could significantly protect against perinatal HI brain injury via anti-apoptotic mechanisms, which offers the possibility of MPA application for the treatment of neonatal HI encephalopathy.

• Journal of Korean Biological Nursing Science
• /
• v.1 no.1
• /
• pp.25-41
• /
• 1999

Physiological activity of osteoblast including bone formation is known to be closely related to the increase of intracellular $Ca^{2+}$ activity($[Ca^{2+}]_i$) in osteoblast. $Ca^{2+}$ is an important intracellular messenger in diverse cellular functions, and regulation of its level is mediated by the transmembrane $Ca^{2+}$ movement via $Ca^{2+}$ channels, $Na^+-Ca^{2+}$ exchange, and by intracellular $Ca^{2+}$ movement through the intracellular stores. The purpose of this study is to investigate how the intracellular $Ca^{2+}$ is regulated in osteoblast-like cells(OLCs) by measuring $Ca^{2+}$ activity with cell imaging technique. OLCs were isolated from femur and tibia of neonatal rats, and cultured for 7 days. Cultured OLCs were loaded with a $Ca^{2+}$-sensitive fluorescent dye, Fura-2, and fluorescence images were monitored with a cooled CCD camera. The images were processed and analyzed with an image analyzing software. The results were as follows. (1) $[Ca^{2+}]_i$ of OLC decreased as the $Ca^{2+}$ concentration in the superfusing Tyrode solution was lowered. When $Na^+$ concentration in the superfusing solution was decreased, $[Ca^{2+}]_i$ increased.. These suggest that $Ca^{2+}$ flux occurs via the $Na^+-Ca^{2+}$ exchange mechanism. (2) When $Na^+$ in the superfusing solution was removed. a transient $Ca^{2+}$, increase($Ca^{2+}$ spike) was occasionally observed. However, $Ca^{2+}$ spike was not observed after adding 1 ${\mu}M$ thapsigargin. This implies that the generation of $Ca^{2+}$ spike is mediated by the release of $Ca^{2+}$ from endoplasmic reticulum(ER). (3) As the $Ca^{2+}$ concentration in the superfusing solution was raised, the frequency of 0mM $Na^+$-induced $Ca^{2+}$ spike increased, suggesting that $Ca^{2+}$-induced $Ca^{2+}$ release(CICR) mechanism exists. (4) After $[Ca^{2+}]_i$ was decreased with the superfusion of $Ca^{2+}$-free solution containing thapsigargin, the recovery of $[Ca^{2+}]_i$ with reperfusion of 2.5mM $Ca^{2+}$ solution transiently exceeded the control level, suggesting that the depletion of $Ca^{2+}$ in ER induces $Ca^{2+}$ influx from extracellular medium via store-operated $Ca^{2+}$ influx(SOCI) mechanism. (5) $[Ca^{2+}]_i$ was not affected by the superfusion of 25mM $K^+$ Tyrode solution. These results suggest that intracellular $Ca^{2+}$ activity in osteoblast is regulated by transmembrane $Ca^{2+}$ flux via $Na^+-Ca^{2+}$ exchange, $Ca^{2+}$ release from the internal store (ER) via $Ca^{2+}$-induced $Ca^{2+}$ release, and store-operated $Ca^{2+}$ influx across the cell membrane.

• The korean journal of orthodontics
• /
• v.24 no.2
• /
• pp.331-348
• /
• 1994

The purpose of this study was to investigate changes in the shape and ultrastructure of the articular disc of the rat mandibular joint with aging. Mechanical stress applied to the articular disc changes during neonatal, suckling, juvenile, adult and senile stages. Mandibular joints of 6 groups of rats(1-, 7-, 17-, 27-, 55-day and over-1-year groups) were removed en bloc and processed for light and electro microscopic study. The changes in the shape of articular disc were examined by light microscope in each group. Structural and ultrastructural changes in the articular disc were examined by light and electron microscope in each group. The results were as follows : In the 1-day and 7-day groups, the articular disc was long and slender in shape and the articular disc was not fitted with the shape of the mandibular fossa and condyle. However' after that time, the anterior and posterior portions of the articular disc were more bulged and the middle portion was shorter and biconcave. Thus the articular disc was well fitted with the shape of the mandibular fossa and condyle. The cell density decreased with aging. In the l -day and 7-day groups, the Golgi apparatus, rough endoplasmic reticulum and free ribosome, which are involved in the synthesis of intracellular and extracellular matrix, were developed. In the 17-day, 27-day and 55-day groups, not only the cell organelles involved in the synthesis of the intracellular and extracellular matrix but also the cell organelles involved in the remodeling of the extracellular matrix(i.e., finger-like cell process, lysosome and mitochondria)were well developed. With advancing age, intracytoplasmic microfilaments were more accumulated and condroid cells increased. In the over-1-year group, the majority of cells of the articular disc were chondroid cells. The majority of cytoplasmic compartment were filled with intracytoplasmic microfilaments and cell organelles were not developed. Therefore, metabolic activities of the cell was markedly reduced and cells contained structures enduring mechanical stress, and cells which were in the process of degeneration were observed occasionally.

• Journal of Ginseng Research
• /
• v.47 no.6
• /
• pp.755-765
• /
• 2023

Background: Caveolin-1, the scaffolding protein of cholesterol-rich invaginations, plays an important role in store-operated Ca²⁺ influx and its phosphorylation at Tyr14 (p-caveolin-1) is vital to mobilize protection against myocardial ischemia (MI) injury. SOCE, comprising STIM1, ORAI1 and TRPC1, contributes to intracellular Ca²⁺ ([Ca²⁺]_i) accumulation in cardiomyocytes. The purified extract of steamed Panax ginseng (EPG) attenuated [Ca²⁺]_i overload against MI injury. Thus, the aim of this study was to investigate the possibility of EPG affecting p-caveolin-1 to further mediate SOCE/[Ca²⁺]_i against MI injury in neonatal rat cardiomyocytes and a rat model. Methods: PP2, an inhibitor of p-caveolin-1, was used. Cell viability, [Ca²⁺]_i concentration were analyzed in cardiomyocytes. In rats, myocardial infarct size, pathological damages, apoptosis and cardiac fibrosis were evaluated, p-caveolin-1 and STIM1 were detected by immunofluorescence, and the levels of caveolin-1, STIM1, ORAI1 and TRPC1 were determined by RT-PCR and Western blot. And, release of LDH, cTnI and BNP was measured. Results: EPG, ginsenosides accounting for 57.96%, suppressed release of LDH, cTnI and BNP, and protected cardiomyocytes by inhibiting Ca²⁺ influx. And, EPG significantly relieved myocardial infarct size, cardiac apoptosis, fibrosis, and ultrastructure abnormality. Moreover, EPG negatively regulated SOCE via increasing p-caveolin-1 protein, decreasing ORAI1 mRNA and protein levels of ORAI1, TRPC1 and STIM1. More importantly, inhibition of the p-caveolin-1 significantly suppressed all of the above cardioprotection of EPG. Conclusions: Caveolin-1 phosphorylation is involved in the protective effects of EPG against MI injury via increasing p-caveolin-1 to negatively regulate SOCE/[Ca²⁺]_i.