• Parasites, Hosts and Diseases
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• v.54 no.2
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• pp.147-154
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• 2016

Toxoplasma gondii infection induces alteration of the host cell cycle and cell proliferation. These changes are not only seen in directly invaded host cells but also in neighboring cells. We tried to identify whether this alteration can be mediated by exosomes secreted by T. gondii-infected host cells. L6 cells, a rat myoblast cell line, and RH strain of T. gondii were selected for this study. L6 cells were infected with or without T. gondii to isolate exosomes. The cellular growth patterns were identified by cell counting with trypan blue under confocal microscopy, and cell cycle changes were investigated by flow cytometry. L6 cells infected with T. gondii showed decreased proliferation compared to uninfected L6 cells and revealed a tendency to stay at S or G2/M cell phase. The treatment of exosomes isolated from T. gondii-infected cells showed attenuation of cell proliferation and slight enhancement of S phase in L6 cells. The cell cycle alteration was not as obvious as reduction of the cell proliferation by the exosome treatment. These changes were transient and disappeared at 48 hr after the exosome treatment. Microarray analysis and web-based tools indicated that various exosomal miRNAs were crucial for the regulation of target genes related to cell proliferation. Collectively, our study demonstrated that the exosomes originating from T. gondii could change the host cell proliferation and alter the host cell cycle.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.121-121
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• 2019

In Islamic dietary guidelines, Halal foods are allowed as edible blessed food. Most foods were categorized within halal for Muslims. The main point of Halal food is that foods are clean in every process and based on Halal standard which might be different in each country. Most pancreatic ${\beta}$ cells synthetize, store, and release insulin. Specific molecular, functional as well as ultrastructural traits of pancreatic ${\beta}$ cells could control their insulin secretion properties and survival phentoype. Insulin-secreting pancreatic ${\beta}$-cells are essential regulators of mammalian metabolism. In addition, the pancreatic ${\beta}$ cell plays an important role in the pathogenesis of type 1 and type 2 diabetes as improving glucose homeostasis by preserving, expanding and improving the function of this key cell type. However, the pharmacological effect of halal food has not been unclear yet, especially food habit-dependent diabetes. The aim of the this study was to determine the preventive effect of Iran plants extract (Almond, Garlic, Cumin, Ginkgo biloba, Holy basil, Psyllium, Satureja khuzistanica, Fenugreek, Green tea, Ipomoea betatas, Blueberry) on RINm5F cells and MIN6 cells as pancreatic ${\beta}$ cell line. The cytotoxicity of the extracts of Iran plants on RINm5F cells and MIN6 cells were measured by using MTT assays. The preventive effects of Iran plant extracts were measured by WST-8 cell proliferation assay on streptozotocin (STZ)-induced cell death in MIN6 cells. In presented result showed that all extract of Iran plants (0.01-10mg/ml) did not show cytotoxicity in RINm5F cells and MIN6 cells. Among non-cytotoxic extract, the protective effects could be detect in high dose concentration. These results suggest that the extract of Iran plants may serve as a potential therapy for diabetes.

• Biomedical Science Letters
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• v.18 no.3
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• pp.193-200
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• 2012

We examined the effects of polyamines such as putrescine and cadaverine on the biosynthesis and secretion of insulin in the mouse pancreatic ${\beta}$-cell line, MIN-6. Basal insulin secretion (BIS) and glucose-stimulated insulin secretion (GSIS) from the MIN-6 cells were significantly increased by 20 min- or 24 h-treatment with micromolar concentrations of polyamines. To determine whether the enhancement was due to increase of insulin production by polyamines, we investigated the insulin mRNA and protein production. Both insulin mRNA and protein production were found to be not significantly affected by the polyamine treatment. Next, we examined the expression of several transcription factors (TFs) related to insulin synthesis and secretion in order to identify upstream events responsible for the promotion of insulin secretion of MIN6 cells by polyamines. Of the 6 TFs tested, MafA was induced by treatment of polyamines. MafA mRNA and protein expressions increased with treatment of polyamines. Overall results suggest that cadaverine and putrescine promote the insulin secretion process rather than the insulin biosynthesis from MIN6 cells. Also MafA may be involved in the enhanced insulin secretion process. Further studies are needed to elucidate the underlying mechanisms for promotion of insulin secretion by polyamines.

• Biomedical Science Letters
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• v.20 no.1
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• pp.14-24
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• 2014

Hypoxia is one of the main reasons for islet apoptosis after transplantation as well as during isolation. In this study, we attempted to determine the potential usefulness of NF-${\kappa}B$ inhibitor for suppression of hypoxia-induced ${\beta}$-cell apoptosis as well as the relationship between IP-10 induction and ${\beta}$-cell apoptosis in hypoxia. To accomplish this, we cultured the mouse pancreatic ${\beta}$-cell line MIN6 in hypoxia (1% $O_2$). Among several examined chemokines, only IP-10 mRNA expression was induced under hypoxia, and this induced IP-10 expression was due to NF-${\kappa}B$ activity. Since a previous study suggested that IP-10 mediates ${\beta}$-cell apoptosis, we measured hypoxia-induced IP-10 protein and examined the effect of anti-IP-10 neutralizing Ab on hypoxia-induced ${\beta}$-cell apoptosis. However, IP-10 protein was not detected, and anti-IP-10 neutralizing Ab did not rescue hypoxia-induced MIN6 apoptosis, indicating that there is no relationship between hypoxia-induced IP-10 mRNA expression and hypoxia-induced ${\beta}$-cell apoptosis. Since it was still not clear if NF-${\kappa}B$ functions as an apoptotic or anti-apoptotic mediator in hypoxia-induced ${\beta}$-cell apoptosis, we examined possible involvement of NF-${\kappa}B$ in hypoxia-induced ${\beta}$-cell apoptosis. Treatment with 1 ${\mu}M$ NF-${\kappa}B$ inhibitor suppressed hypoxiainduced apoptosis by more than 50%, while 10 ${\mu}M$ AP-1 or 4 ${\mu}M$ NF-AT inhibitor did not, indicating involvement of NF-${\kappa}B$ in hypoxia-induced ${\beta}$-cell apoptosis. Overall, these results suggest that IP-10 is not involved in hypoxia-induced ${\beta}$-cell apoptosis, and that NF-${\kappa}B$ inhibitor can be useful for ameliorating hypoxia-induced ${\beta}$-cell apoptosis.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.24 no.2
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• pp.249-260
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• 1994

The purpose of this study was to aid in the radiation therapy of head and neck cancer patients. For this study, radiation survival curves were generated for Bl6, MG-63 and YAC-l cell lines using semiautomated MTT assay and Dye Exclusion Assay. Irradiation of 2, 4, 6, 8, 10Gy were delivered at room temperature at a dose rate of 210.2cGy/min using / sup 60/Co γ-ray Irradiator ALOORAOO 8. The viable cells were determined for each radiation dose and compared to control values. The obtained results were as follows: 1. There was significantly different absorbance at 10Gy on B16 cell line in MTT assay(P<0.05). 2. There was significantly different absorbance at 4, 6, 8, 10Gy on MG-63 cell line in MTT assay(P<0.05). 3. YAC-l cell line was more sensitive than B16 or MG-63 cell line to all doses of radiation(P<0.05). 4. There was significantly different absorbance among all tumor cell lines except between B16 and MG-63 cell line at ZGy in MTT assay(P<0.05). 5. Good correlation was obtained between MTT assay and DEA(P<0.05). The efficient of correlation of B16, MG-63 and YAC-l cell line was 0.845, 0.824 and 0.906, respectively.

• The Korean Journal of Physiology and Pharmacology
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• v.7 no.3
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• pp.163-168
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• 2003

The reactive oxygen species (ROS) are considered to be an important mediator in pancreatic ${\beta}$ cell destruction, thereby triggering the development of insulin-dependent diabetes mellitus. In the present study, HIV-1 Tat-mediated transduction of Cu,Zn-superoxide dismutase (SOD) was investigated to evaluate its protective potential against streptozotocin (STZ)-induced cytotoxicity in insulin-producing MIN6N cells. Tat-SOD fusion protein was successfully delivered into MIN6N cells in a dose-dependent manner and the transduced fusion protein was enzymatically active for 48 h. The STZ induced-cell destruction, superoxide anion radical production, and DNA fragmentation of MIN6N cells were significantly decreased in the cells pretreated with Tat-SOD for 1 h. Furthermore, the transduction of Tat-SOD increased Bcl-2 and heat shock protein 70 (hsp70) expressions in cells exposed to STZ, which might be partly responsible for the effect of Tat-SOD. These results suggest that an increased of free radical scavenging activity by transduction of Tat-SOD enhanced the tolerance of the cell against oxidative stress in STZ-treated MIN6N cells. Therefore, this Tat-SOD transduction technique may provide a new strategy to protect the pancreatic ${\beta}$ cell destruction in ROS-mediated diabetes.

• Applied Microscopy
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• v.27 no.2
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• pp.121-130
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• 1997

It has been demonstrated that majority of cells in the mammalian body such as myocytes and epithelial cells of skin and intestine respond to mechanical force or environmental factors and exhibit partial disruption of cell membrane, i. e., cell wounding, even in a physiological condition. Myocardial cells are rather apt to be wounded than other cells since they are definitely exposed to mechanical stress by contraction-relaxation and blood flow. However, the mechanism how myocardial cells protect themselves against cell wounding is not yet clarified. On this background, the present study was performed to elucidate whether albumin leakage is related to cell wounding and to assess whether diltiazem, a potent calcium channel blocker, is beneficial in isoproterenol-induced cell wounding in the heart. Hearts isolated from New Zealand White rabbits ($1.5\sim2.0kg$ body weight, n=20) were perfused with Tyrode solution by Langendorff technique. After stabilization of baseline hemodynamics, the hearts were subjected to bolus administration of isoproterenol and diltiazem as following order: $1.6{\mu}M$ isoproterenol at zero min (the beginning point): $16{\mu}M$ diltiazem at 20min; $1.6{\mu}M$ isoproterenol at 25min; $16{\mu}M$ isoproterenol at 45 min; $160{\mu}M$ diltiazem at 65 min; $16{\mu}M$ isoproterenol at 70 min. During all experiments, the left ventricular function was recorded, albumin leakage in the coronary effluents was analyzed by electrophoresis and Western blot, and myocardial cell membranes were examined by conventional transmission electron microscopy. Data were analyzed by t-test and linear regression test. Isoproterenol significantly increased the inotropic and chronotropic contractions, coronary flow, and frequency of arrhythmia, however, diltiazem did not influence on hemodynamics except decrease in the frequency of arrhythmia and a slight decrease in contractility. Isoproterenol also resulted partial disruption of myocardial cell membrane and inclose in albumin leakage, while diltiazem pretreatment showed number of electron-dense plaques in the cell membrane and a tendency of decrease in albumin leakage. These results indicate that albumin leakage may be an indirect index of cell wounding in the heart and diltiazem nay be beneficial to protect myocardial cells against isoproterenol-induced cell wounding. It is likely that diltiazem promotes resealing process of the cell membrane.

• Animal cells and systems
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• v.11 no.1
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• pp.17-22
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• 2007

The effects of antimetabolite 6-AN (6-amino-nicotinamide) on viability and morphology of L6 myoblast cells have been investigated. 6-AN ($100{\mu}M$) induced a time-dependent decrease in cell viability with respect to the untreated control cells. Following 6-AN administration the viability rate started to decline sharply, reaching about 23% of the untreated control cells at 48 h. Inverted phase-contrast microscopy revealed that 6-AN caused characteristic morphological changes such as irregularly elongated and stellate shape of cells, round-shaped nucleus, cytoplasmic vacuolization, irregular cell arrangements and formation of large spaces among cell clusters. The concentrations of ATP and $NAD^{+}$ in the 6-AN treated cells were significantly lower (p < 0.01) than those of the untreated control cells. In contrast, the concentration of AMP was significantly increased by the 6-AN treatment. Activities of catalase, superoxide dismutase and glutathione peroxidase in 6-AN treated cells were significantly higher (p < 0.01) than those of the untreated control cells. The activities of glyceraldehyde-3-phosphate dehydrogenase in 6-AN treated cells were significantly lower (p < 0.01) than those of the untreated control cells. The results suggest that 6-AN caused marked reduction of cell viability and alterations of some important metabolites and enzymes.

• Korean Journal of Environmental Biology
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• v.31 no.4
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• pp.376-382
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• 2013

[6]-Gingerol, a major polyphenol of ginger (Zingiber officinale), exhibits a variety of biological properties including anti-oxidant, anti-inflammatory and anti-cancer activity. However, the radioprotective effect of [6]-gingerol is still unknown. The aim of this study was to investigate the radioprotective effect of [6]-gingerol against radiation-induced cell cytotoxicity and oxidative stress in HepG2 cells. [6]-Gingerol pretreatment attenuated radiation-induced cell cytotoxicity caused by 5Gy (half lethal dose, $LD_{50}$ of HepG2 cells). The measurements of superoxide dismutase (SOD) and catalase (CAT) activity were also performed. The results showed that [6]-gingerol pretreatment reduced increasing SOD and CAT activity after exposure of IR, indicating that [6]-gingerol protected oxidative stress by regulating cellular antioxidant enzyme (SOD and CAT) activity. These findings suggest that [6]-gingerol acts as a radioprotector by attenuating cell cytotoxicity and oxidative stress.

• Restorative Dentistry and Endodontics
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• v.34 no.6
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• pp.491-499
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• 2009

This study examined the influence of the storage methods on the viability of oral epithelial cells using conventional cell freezing storage, slow freezing preservation, rapid freezing preservation, and slow freezing preservation with a pressure of 2 Mpa or 3 Mpa. The cell viability was evaluated by cell counting, WST-1 and the clonogenic capacity after 6 days of freezing storage. After 6 days, the frozen cells were thawed rapidly, and the cell counting. WST-1, and clonogenic capacity values were measured and compared. 1. The results from cell counting demonstrated that conventional cryopreservation, slow freezing under a 2 Mpa pressure and slow freezing under a 3 Mpa pressure showed significantly higher values than slow freezing preservation and rapid freezing preservation (p < 0.05). 2. The results from the optical density by WST-1 demonstrated that slow freezing under a 2 Mpa pressure showed significantly higher values than slow freezing preservation and rapid freezing preservation (p<0.05). 3. The clonogenic capacity demonstrated that slow freezing under a 2 Mpa pressure showed significantly higher values than slow freezing preservation and rapid freezing preservation (p < 0.05).