• Journal of Life Science
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• v.21 no.7
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• pp.953-960
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• 2011

Necrosis is characterized by the cell membrane rupture and release of the cellular contents, including high-mobility group box 1 protein (HMGB1), into the extracellular microenvironment. HMGB1 acts as a transcriptional regulator in nuclei, but exerts a pro-inflammatory and tumor-promoting cytokine activity when released into the extracellular space. Its overexpression is associated with tumor progression and chemoresistance. Thus, HMGB1 acts as a clinically important molecule in tumor biology. In this study, we examined whether HMGB1 affects cell death induced by anti-cancer drugs. Here we show that HMGB1 prevented cisplatin (alkylating agent)-induced apoptosis and switched the cell fate to necrosis in MCF-7, MDA-MB231, and MDA-MB361 cells. Similar apoptosis-to-necrosis switch effects of HMGB1 were observed in cells treated with 4-HC, another alkylating agent. In contrast, HMGB1 did not exert any significant effects on docetaxel (DOC)-induced apoptosis in MCF-7 cells. We also show that cisplatin-induced apoptosis was switched to necrosis in MCF-7 multicellular tumor spheroids (MTS) that were cultured for 8 days and had necrotic cores, but DOC-induced apoptosis was prevented without the apoptosis-to-necrosis switch. Finally, the levels of RAGE, a receptor of HMGB1, were increased with extended culture of MTS. These findings demonstrate that HMGB1 switches alkylating agent-induced apoptosis to necrosis, suggesting that the strategy to prevent necrosis occurring as an undesirable action of alkylating agent-based chemotherapy should be delineated to improve the efficacy of chemotherapy for cancer.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 1999.06a
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• pp.97-117
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• 1999

This study was performed to investigate the effect of pork on the cadmium detoxification in rats. Ninety male Sprague-Dawley rats weighing $125.3{\pm}1.4g$ were divided into five groups based on cadmium treatment(0, 25, 50, 100, 250ppm) and five levels of Cd in AIN-76 purified diet had been fed for 8 weeks. Cadmium was supplemented with a form of $CdCl_2$.. During following 8 weeks of intoxication, casein was replaced by pork and the effect of pork on cadmium- detoxification was compared with casein. After 8 weeks of Cd intake had resulted in apparent cadmium intoxication; reduced growth rate, enlarged kidney and testis, decreased hematocrit value and hemoglobin content in response to the supplemented Cd levels in the diets. Discontinuing cadmium feeding, the body weights were relieved. Pork-fed groups seemed to have higher body weight than casein-fed groups. Hemoglobin content and hematocrit value became normal range at detoxification stage. The weights of liver, kidney, and testis were decreased along with cadmium intake. However, organ weight ratio was not affected by cadmium. Cadmium accumulation in liver and kidney showed a tendency to increase in the cadmium-exposed groups. The levels of metallothionein were also significantly elevated in the tissues of liver in response to the levels of Cd supplemented(p<0.05). Cadmium concentration in kidney was two times higher than that in liver. Cadmium removal rate of liver was higher than that of kidney. Cadmium accumulation of the pork-fed group was lower than that of casein. Especially, the factors which affected the cadmium contents in kidney were $Cd^{***}$ and $Cd{\times}pork^{***}$. Metallothionein(MT) was increased with cadmium, and MT was not likely to be affected by pork. Based on the findings from gross lesion, rats fed 250ppm of Cd were externally emaciated, had exposed penis and observed atrophies of kidney and testis. Histopathological observation seemed that the liver of groups feeding Cd supplemented diets showed cellular degeneration and accumulation of eosinophilic materials in the capillaries. In kidney, rats fed Cd diets had shown tubular epithelium degeneration and lesions of basophilic materials, while testis were weakened in numbers of spermatid and sporadically enlarged of giant cells. But the rats administered cadmium-detoxified diet supplemented pork for 7 weeks were shown individually decreased lesions compared with the rats supplied with casein diet.

• Journal of Life Science
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• v.27 no.12
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• pp.1445-1451
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• 2017

Mitochondria play a central role in energy generation by using electron transport coupled with oxidative phosphorylation. They also participate in other important cellular functions including metabolism, apoptosis, signaling, and reactive oxygen species production. Therefore, mitochondrial dysfunction is known to contribute to a variety of human diseases. Furthermore, there are various inherited diseases of energy metabolism due to mitochondrial DNA (mtDNA) mutations. Unfortunately, therapeutic options for these inherited mtDNA diseases are extremely limited. In this regard, mitochondrial replacement techniques are taking on increased importance in developing a clinical approach to inherited mtDNA diseases. In this study, green fluorescence protein (GFP)-tagged mitochondria were isolated by differential centrifugation from a mammalian cell line. Using microinjection technique, the isolated GFP-tagged mitochondria were then transferred to bovine oocytes that were triggered for early development. During the early developmental period from bovine oocytes to blastocysts, the transferred mitochondria were observed using fluorescent microscopy. The microinjected mitochondria were dispersed rapidly into the cytoplasm of oocytes and were passed down to subsequent cells of 2-cell, 4-cell, 8-cell, morula, and blastocyst stages. Together, these results demonstrate a successful in vitro transfer of isolated mitochondria to oocytes and provide a model for mitochondrial replacement implicated in inherited mtDNA diseases and animal cloning.

• Animal cells and systems
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• v.3 no.1
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• pp.89-96
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• 1999

Nucleotide sequences of a 501 base-pair (bp) fragment in the mitochondrial cytochrome b (cyt b) gene were analyzed for 12 populations of Rana rugosa from Korea and Japan using a polymerase chain reaction (PCR) and direct silver sequencing. Two genetically distinct groups (type-A and type-B) were found in Korea. Type-A was found throughout most of South Korea and type-B was restricted to the mid-southeastern regions (Samchok, Yongdok, Chongsong and Pohang). But in the Tonghae population, both types were found. The level of mitochondrial DNA (mtDNA) sequence differences ranged from 0% to .0.8% among six populations of type-A, and 0 to 1.0% among 4 populations of type-B. However, sequence differences between type-A and type-B ranged from 5.4% to 6.6%, Using Kimura's two-parameter distance, the level of genetic sequence divergence between type-A and type-B was 6.7%. The Japanese R. rugosa was clustered very far from the Korean R. rugosa with 14.7%. In the neighbor-joining and UPGMA tree, all Korean samples were grouped, but subdivided into two types in 99% of the bootstrap iteration.

• Animal cells and systems
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• v.14 no.2
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• pp.137-145
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• 2010

Four specimens of unknown Coilia sp. were collected for the first time from the Yellow Sea in 2008 and compared with Coilia mystus and Coilia nasus. Coilia sp. showed similar morphology to C. mystus and C. nasus, but differed in that its tail was considerably shorter. We conducted an analysis of the morphological and genetic characteristics in an effort to clarify the taxonomic position of Coilia sp. In counts and measurements, Coilia sp. were well distinguished from C. nasus by the number of scutes (42-44 in Coilia sp. vs. 40-45 in C. mystus vs. 45-55 in C. nasus), ratio of dorsal base length to head length (43.4-47.6 vs. 37.9-47.6 vs. 33.0-41.0), and eye length to head length (19.2-20.8 vs. 17.0-22.4 vs. 13.8-18.2). In caudal skeleton of Coilia sp., urostyle, hypural and epural bones were not observed; instead of them, caudal fin rays were supported by the last vertebra, neural and haemal spines' extension. The molecular phylogenetic relationship was analyzed using 414 base-pair 12S rRNA mitochondrial DNA sequences. The Kimura-2-parameter distance between Coilia sp. and C. mystus was 0.3%, but was 1.3% between Coilia sp. and C. nasus. Both the neighbor-joining tree and maximum-likelihood tree showed that Coilia sp. are closely clustered with C. mystus. Therefore, our results suggest that the Coilia sp. may be a deformed fish of C. mystus.

• Korean Journal of Veterinary Research
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• v.33 no.4
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• pp.701-710
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• 1993

The pine needles, Pinus densiflow Sieb. et Zucc., which is a feed for goats showing a low incidence rate of cancer were evaluated to confirm the potent anticancer effects, with or without several conventional anticancer drugs. The pine needles collected from Mt. Buk-Han located near Seoul were extracted with 95% methanol and methand and concentrated. From the methanol extract, SOM-A, was extracted dichlormethane and SOM-B was extracted with ethyl acetate. SOM-C was extracted with distilled water. These extracts were tested for their antitumor activities in vitro and in vivo. Among them, SOM-A and SOM-C exhibited potent antitumor activities described as belows. 1. The cytotoxic effects of SOM-A and SOM-C were examined against in vitro cultured murine and humman tumor cells. SOM-A showed strong cytotoxicity against human tumor cell lines and SOM-C showed strong cytotoxicity against murine tumor cell lines tested. 2. The antitumor effects of SOM-A and SOM-C were examined against P388 and L1210 of mouse ascitic tumors. The highest mean survival time(MST) ration was 151%(P388) for SOM-C(90mg/kg). 3. To compare the antitumor effects of SOM-A, SOM-B, and SOM-C against solid tumors, S-180 and Ehrlich carcinoma were implanted subcutaneously to mice on Day O. The drugs were given intraperitoneally to mice once a day on Days 1-20, and the tumor weights were measured on Day 21. SOM-A showed inhibition of tumor growth more than 50% in the experiment on S-180 and Ehrlich, and SOM-C also markedly inhibited tumor growth. However, SOM-B had no effect. 4. SOM-C combined with ${\alpha}$-interferon and SOM-C combined with Mitomycin-C enhanced the antitumor activities against murine ascitic tumors P388 leukemia.

• Animal cells and systems
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• v.12 no.4
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• pp.269-277
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• 2008

Siberian flying squirrel, an endangered species in South Korea, is distributed through major mountain regions of South Korea. The number of Siberian flying squirrel(Pteromys volans) in South Korea has decreased and their habitats are fragmented and isolated because of anthropogenic activities. So far no molecular genetic data has, however, been available for their conservation and management. To obtain better information concerning genetic diversity and phylogenetic relationships of the Siberian flying squirrel in South Korea, we examined 14 individuals from South Korea, 7 individuals from Russia, and 5 individuals from northeastern China along with previously published 29 haplotypes for 1,140 bp of the mtDNA cytochrome b gene. The 14 new individuals from South Korea had 7 haplotypes which were not observed in the regions of Russia and Hokkaido. The level of genetic diversity(0.616%) in the South Korean population was lower than that in eastern Russia(0.950%). The geographical distribution of mtDNA haplotypes and reduced median network confirmed that there are three major lineages of Siberian flying squirrel, occupying; Far Eastern, northern Eurasia, and the island of Hokkaido. The South Korean population only slightly distinct from the Eurasia, and eastern Russian population, and is part of the lineage Far Eastern. Based on these, we suggest that the South Korean population could be considered to belong to one partial ESU(Far Eastern) of three partial ESUs but a different management unit. However, the conservation priorities should be reconfirmed by nuclear genetic marker and ecological data.

• Korean Journal of Pharmacognosy
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• v.39 no.4
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• pp.335-340
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• 2008

Diabetes mellitus is metabolic disorder characterized by hyperglycemia caused by insufficient insulin secretion or insulin receptor insensitivity to endogenous insulin. It is well-known that hyperglycemia is one of the main causes of oxidative stress in both type 1 and 2 diabetes. Oxidative stress is related by death of pancreatic ${\beta}$ cell and dysfunction of ${\beta}$ cell. Although ${\beta}$ cell death or dysfunction is induced by many substances or molecules, increased evidences that oxidative stress plays a crucial role in ${\beta}$ cell death or dysfunction. Considering the importance of oxidative stress in the pathogenesis of diabetes mellitus, we investigated the cytoprotective effects against hydrogen peroxide-induced oxidative stress in pancreatic ${\beta}$ cell line RIN-m5F cell. 110 Plant sources were collected in Mt. Baek-du, and extracted with methanol. These extracts had been screened the protective effects against hydrogen peroxide-induced oxidative damage in RIN-m5F cells at 50 and 200 ${\mu}g$/ml. Of these, ten methanolic extracts, aerial part of Erigenron cannadensis, aerial part of Lespedeza juncea, whole plant of Alopecurus aequalis, fruit of Lycium chinense, leaf of Morus alba, rhizome of Polygonatum odoratum, root of Ampelosis japonica, whole plant of Ranunculus japonicus, aerial part of Polygonum sieboldii, rhizome of Arisaema amurense var. violaceum showed significant protective effects against hydrogen peroxide-induced oxidative damage in pancreatic ${\beta}$ cell line RIN-m5F cell.

• Molecules and Cells
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• v.38 no.10
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• pp.876-885
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• 2015

N-acetyl-D-glucosamine kinase (NAGK) plays an enzyme activity-independent, non-canonical role in the dendritogenesis of hippocampal neurons in culture. In this study, we investigated its role in axonal development. We found NAGK was distributed throughout neurons until developmental stage 3 (axonal outgrowth), and that its axonal expression remarkably decreased during stage 4 (dendritic outgrowth) and became negligible in stage 5 (mature). Immunocytochemistry (ICC) showed colocalization of NAGK with tubulin in hippocampal neurons and with Golgi in somata, dendrites, and nascent axons. A proximity ligation assay (PLA) for NAGK and Golgi marker protein followed by ICC for tubulin or dynein light chain roadblock type 1 (DYNLRB1) in stage 3 neurons showed NAGK-Golgi complex colocalized with DYNLRB1 at the tips of microtubule (MT) fibers in axonal growth cones and in somatodendritic areas. PLAs for NAGK-dynein combined with tubulin or Golgi ICC showed similar signal patterns, indicating a three way interaction between NAGK, dynein, and Golgi in growing axons. In addition, overexpression of the NAGK gene and of kinase mutant NAGK genes increased axonal lengths, and knockdown of NAGK by small hairpin (sh) RNA reduced axonal lengths; suggesting a structural role for NAGK in axonal growth. Finally, transfection of 'DYNLRB1 (74-96)', a small peptide derived from DYNLRB1's C-terminal, which binds with NAGK, resulted in neurons with shorter axons in culture. The authors suggest a NAGK-dynein-Golgi tripartite interaction in growing axons is instrumental during early axonal development.

• The Korean Journal of Physiology and Pharmacology
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• v.4 no.1
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• pp.63-72
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• 2000

Chronic exposure to cadmium (Cd) results in an inhibition of protein endocytosis in the renal proximal tubule, leading to proteinuria. In order to gain insight into the mechanism by which Cd impairs the protein endocytosis, we investigated the effect of Cd on the acidification of renal cortical endocytotic vesicles (endosomes). The endosomal acidification was assessed by measuring the pH gradient-dependent fluorescence change, using acridine orange or FITC-dextran as a probe. In renal endosomes isolated from Cd-intoxicated rats, the $V_{max}$ of ATP-driven fluorescence quenching ($H^+-ATPase$ dependent intravesicular acidification) was significantly attenuated with no substantial changes in the apparent $K_m,$ indicating that the capacity of acidification was reduced. When endosomes from normal animals were directly exposed to free Cd in vitro, the $V_{max}$ was slightly reduced, whereas the $K_m$ was markedly increased, implying that the biochemical property of the $H^+-ATPase$ was altered by Cd. In endosomes exposed to free Cd in vitro, the rate of dissipation of the transmembrane pH gradient after $H^+-ATPase$ inhibition appeared to be significantly faster compared to that in normal endosomes, indicating that the $H^+-conductance$ of the membrane was increased by Cd. These results suggest that in long-term Cd-exposed animals, free Cd ions liberated in the proximal tubular cytoplasm by lysosomal degradation of cadmium-metallothionein complex (CdMT) may impair endosomal acidification 1) by reducing the $H^+-ATPase$ density in the endosomal membrane, 2) by suppressing the intrinsic $H^+-ATPase$ activity, and 3) possibly by increasing the membrane conductance to $H^+$ ion. Such effects of Cd could be responsible for the alterations of proximal tubular endocytotic activities, protein reabsorption and various transporter distributions observed in Cd-exposed cells and animals.