• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.3
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• pp.305-313
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• 1985

There is a trend that the total number of cancer cases is steadily increasing as the population grows. It has been estimated that 85% of the cancer rate in the U.S. is attributed to environmental factors. Among the environmental factors, diet and nutrition appear to be related to the largest number of human cancers. Diet and nutrition might be related to cancer by several mechanisms. Food may contain a direct carcinogen or precursors that become carcinogens by spontanous reactions, or by host metabolism, or through the actions of microbial flora. Chemicals that cause cancers generally have reactive electrophilic centers which can combine with electron-rich atoms in nucleic acids and cause cancers by changing the genetic activity of the cells. A variety of factors in foods might be involved in the etiology of carcinogenesis. Chemicals in food that cause cancers include carcinogens of plants and animal origin and also those in drinking water. Other then these, fungal metabolites alcohol, asbestos, heavy metals, pesticides, and food additives might be included as food carcinogenesis. The method of cooking foods also might contribute to carcinogenesis. Some chemicals in foods act as promoters in carcinogenesis. Prevention of cancers by dietary practises have received much interest. Consumption of certain vegetables or cellulose can reduce carcinogenic activity of several compounds. A variety of antioxidants or micronutrients may be effective anticarciongens. Glutathione in the soluble fraction of the cells, is a major defense against oxidative and alkylating carcinogens. Recently anticarcinogenic activity of chlorophyll was demonstrated. Daily consumption of milk appears to effectively reduce stomach cancer.

• Preventive Nutrition and Food Science
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• v.6 no.2
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• pp.126-132
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• 2001

Methanol extracts form four kinds of kimchi, which were differently prepared in kinds and levels of sub-ingredients, were given to Balb/c mice for 3 weeks (0.5 mg/kg/day). Peritoneal macrophages isolated from mice treated with kimchi extracts and saline were stimulated by lipopolysaccharide (LPS). K3 and K4 kimchis, containing more red pepper powder, garlic, Chinese pepper powder, mustard leaf and organically cultivated Korean cabbage, significantly increased NO production by the activated macrophages (p<0.05). K1, K2, K3 and K4 kimchi extracts (0.01, 0.1, 1.0 $\mu\textrm{g}$) significantly reduced the increased TGF-$\beta$1 production of H.pylori lysate (0.01 $\mu\textrm{g}$)-activated human epithelial RPMI 2650 cells (5$\times$10$^{4}$ cells/mL) at 24 and 48 hrs of treatment (p<0.01). However, the decreased TGF-$\beta$1 $\alpha$ production of RPMI 2650 cells by H. pylori lysate increased by treatment with kimchi extract for 72 hrs. Especially, K4 kimchi (containing organically cultivated Korean cabbage and more ingredients, modulated TGF-$\beta$1 production of H. pylori lysate-activated RPMI 2650 cells to the normal level (control) by treatment for 48 hrs. The treatment of K1 and K4 kimchi enhanced the LPS (0.01 $\mu\textrm{g}$/mL)-induced IL-6 production of splenocytes. The results suggest that kimchi might have an beneficial effect on cancer prevention due in part to the function enhancing NO production of activated macrophages. Our data suggest that kimchi could modulate TGF-$\beta$1 production by cancer cells and IL-6 production of splenocytes, thereby possibly contributing to control carcinogenesis and the immune system.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.5
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• pp.733-742
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• 2014

The glucagon-like peptide 2 (GLP-2) that is expressed in intestine epithelial cells of mammals, is important for intestinal barrier function and regulation of tight junction (TJ) proteins. However, there is little known about the intracellular mechanisms of GLP-2 in the regulation of TJ proteins in piglets' intestinal epithelial cells. The purpose of this study is to test the hypothesis that GLP-2 regulates the expressions of TJ proteins in the mitogen-activated protein kinase (MAPK) signaling pathway in piglets' intestinal epithelial cells. The jejunal tissues were cultured in a Dulbecco's modified Eagle's medium/high glucose medium containing supplemental 0 to 100 nmol/L GLP-2. At 72 h after the treatment with the appropriate concentrations of GLP-2, the mRNA and protein expressions of zonula occludens-1 (ZO-1), occludin and claudin-1 were increased (p<0.05). U0126, an MAPK kinase inhibitor, prevented the mRNA and protein expressions of ZO-1, occludin, claudin-1 increase induced by GLP-2 (p<0.05). In conclusion, these results indicated that GLP-2 could improve the expression of TJ proteins in weaned pigs' jejunal epithelium, and the underlying mechanism may due to the MAPK signaling pathway.

• Nutrition Research and Practice
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• v.15 no.5
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• pp.568-578
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• 2021

BACKGROUND/OBJECTIVES: Psidium guajava L. (guava) leaves have been shown to exhibit hypoglycemic and antidiabetic effects in rodents. This study investigated the effects of guava leaf extract on adipogenesis, glucose uptake, and lipolysis of adipocytes to examine whether the antidiabetic properties are mediated through direct effects on adipocytes. MATERIALS/METHODS: 3T3-L1 cells were treated with 25, 50, 100 ㎍/mL of methanol extract from guava leaf extract (GLE) or 0.1% dimethyl sulfoxide as a control. Lipid accumulation was evaluated with Oil Red O Staining and AdipoRed assay. Immunoblotting was performed to measure the expression of adipogenic transcription factors, fatty acid synthase (FAS), and AMP-activated protein kinase (AMPK). Glucose uptake under basal or insulin-stimulated condition was measured using a glucose analog 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl) amino]-2-deoxy-D-glucose. Lipolysis from fully differentiated adipocytes was measured by free fatty acids release into the culture medium in the presence or absence of epinephrine. RESULTS: Oil Red O staining and AdipoRed assay have shown that GLE treatment reduced lipid accumulation during adipocyte differentiation. Mitotic clonal expansion, an early essential event for adipocyte differentiation, was inhibited by GLE treatment. GLE inhibited the expression of transcription factors involved in adipocyte differentiation, such as peroxisome proliferator-activated receptor 𝛄 (PPAR𝛄), CCAAT/enhancer-binding protein α (C/EBPα), and sterol regulatory element-binding protein-1c (SREBP-1c). FAS expression was also decreased while the phosphorylation of AMPK was increased by GLE treatment. In addition, GLE increased insulin-induced glucose uptake into adipocytes. In lipid-filled mature adipocytes, GLE enhanced epinephrine-induced lipolysis but reduced basal lipolysis dose-dependently. CONCLUSIONS: The results show that GLE inhibits adipogenesis and improves adipocyte function by reducing basal lipolysis and increasing insulin-stimulated glucose uptake in adipocytes, which can be partly associated with antidiabetic effects of guava leaves.

• Preventive Nutrition and Food Science
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• v.5 no.2
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• pp.114-118
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• 2000

The inhibitory effects of doenjang extracts and linoleic acid(LA) which was identified as one of the active compounds in doenjang on the growth of human cancer cells were studied, comparing to the actions on normal cells. Methanol extract and hexane fraction from doenjang exhibited the strong growth inhibitory effect on HT-29 human colon carcinoma cells. Inhibitory effects of chloroform, ethyl acetate, butanol and aqueous fractions on the cancer cells were observed, moderately or weakly. When cell counts of SNU-C$_1$human colon carcinoma cells were determined daily for 6 days, the inhibitory effect of hexane fraction on this cell line was higher than that of the methanol extract from doenjang. LA completely suppressed the growth of SNU-C$_1$cells after 4 days, while conjugated linoleic acid(CLA) resulted in 98% inhibition after 6 days. With the addition of LA and other free fatty acids such as stearic acid, oleic acid, linolenic acid and ${\gamma}$-linolenic acid (${\gamma}$-LnA) to the culture system, the growth of HT-29 cells and SNU-C$_1$cells was greatly suppressed after 6 days. Inhibitory effects of LA ${\gamma}$-LnA on the growth of these cells were stronger than other fatty acids. On the growth of AZ-521 human gastric carcinoma cells, LA and CLA completely cuppressed the growth of the cells after 4 days and 3 days, respectively. At the level of 0.001%~0.01% of LA, there was no cytotoxic effect on normal rat kidney cells and normal intestine human cells. These results showed that LA, a major active compound of doenjang, had strong inhibitory effects on the growth of human cancer cells without damaging normal cells.

• Journal of Nutrition and Health
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• v.36 no.4
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• pp.368-375
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• 2003

Cancer cachexia, characterized by weight loss and progressive tissue wasting, has been postulated to be mediated by cytokines. This study was conducted to evaluate the effect of Korean Traditional Medicine (KTM ; mokhyang, jisil, osooyu) mixture on food intake, blood cytokines level and blood nutrients status of the cachexia induced-mice. Thirty male Balb/c mice aged 6-8 weets were blocked into 3 groups that were Normal (no colon26 cells) Control (colon 26 cells) and KTM (colon26 cells + KTM extract mixture) group. In Control and KTM groups, murine adenocarcinoma colon 26 cells were injected subcutaneously to induce cachexia. KTM mice were given 200 ul KTM extract mixture (7%) per day. Half of each groups were sacrificed at the 14 th day to see serum cytokines & nutrients and the others were fed until almost of control group died to see life span. food intake and body weight were decreased significantly in cachexia induced groups. Tumor weight of KTM group was significantly lower than control group. Serum cytokines (IL-1$\beta$ and TNF-$\alpha$) level of cachexia induced groups were increased than those of normal group, and those of KTM group were significantly lower than the level of control group. Total serum protein and serum albumin were higher in KTM group than other groups. TG and fatty acid were lower in cachexia induced groups than normal group. HDL-cholesterol in serum was increased in KTM group. Effect of oral administration of KTM extract mixture on survival time of colon26 bearing mice showed extension of the life span. Overall, this study showed that KTM (mokhyang, jisil, osooyu) extract mixture inhibited the growth of cancer cell, changed the secretion of cytokines induced by colon26 adenocarcinoma in mice, and changed nutrition metabolism.

• Proceedings of the KSCN Conference
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• 2004.05a
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• pp.439.2-439
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• 2004

Melatonin in mammals, produced by the pineal gland and elsewhere, has shown antioxidant and neuroprotective properties in neuronal cells. We investigated whether melatonin would increase newly-born cells (cell proliferation) in the dentate gyrus of maternally-separated rats. To examine the effect of melatonin on cell proliferation of the dentate gyrus in maternally-separated rats, 5-bromo-2'-deoxyuridine (BrdU) immunohistochemistry was performed.(omitted)

• The Korean Journal of Food And Nutrition
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• v.1 no.1
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• pp.3-6
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• 1988

For the purpose of the production of yeast cell protein from rice bran oil, it's assimillating yeast(E222) was isolating from soil and the resulting of identification was shown that it was belonging to Candida aibican species Total free amino acids from yeast cells were shown 0.05% per gram. Nine other species of amino acids as well as glycine, glutamic acid, alanine, leucine and aspartic acid were produced from yeast cells.

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.05a
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• pp.115-115
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• 2001

Regular green tea consumption has been associated with a reduced risk of cancer, partly via antioxidant effects of green tea in protecting cellular components against free radical. In the present study, we evaluated the effect of green tea extract (GTE) on oxidative damage to DNA in CHL cells.(omitted)

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.3
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• pp.380-386
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• 1994

The behavior of glycogen and histological changes of hepatic tissues in the liver of rats, aged 6 to 7 weeks, fed 18% casein diet under control, gramoxone and gramoxone + vitamin C(Vt. C) diets has been investigated in a comined histropathological and histochemical studies. Cloudy swelling and fat changes of hepatic cells were observed in the gramoxone group with the duration of feeding time. Fat changes of hepatic cells were observed more obviously than cloudy welling, especially in the hepatic cells of periportal area. The number of Kupffer's cells increased signifciantly in the gramoxone group fed for 4weeks. The cloudy swelling and fat changes decreased obviously in the gramxone + Vt. C group. Glycogen content of heaptic cells tended to increase slightly in the gramoxone group as compared with the control group . moreover, glycogen depositons were higher in the hepatic cells where fat changes were obvious. It seems to be that Vt.C alleviating effects on the gramoxone toxicity in the patterns of glycogen distribution and histological structure of heaptic tissues.