• Preventive Nutrition and Food Science
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• 제8권3호
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• pp.284-288
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• 2003

In this study, we investigated the effects of green tea and Pueraria radix tea on the production of Apo B$_{100}$ in Hep G$_2$ liver cells and on the expression of the low density lipoprotein (LDL) receptor. Treatment with green tea resulted in a 60.7% decrease on the Apo B$_{100}$ concentration in Hep G$_2$ cells. Pueraria radix tea decreased Apo B$_{100}$ concentration by 63.5% in Hep G$_2$ cells. Green tea and Pueraria radix tea significantly decreased Apo B$_{100}$ concentration by 64.8% and 61.8%, respectively, in the media. Treatment of the cells with green tea and Pueraria radix tea also significantly decreased the intracellular total cholesterol, but total cholesterol concentrations in the media increased by 26.4% (green tea) and 23.6% (Pueraria radix tea) above that measured in the media of control cells. The addition of green tea and Pueraria radix to the media of the Hep Gz cells increased the LDL receptor binding activities by 84.1% and 79.4%, respectively.

• Preventive Nutrition and Food Science
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• 제7권4호
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• pp.353-357
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• 2002

We have previously demonstrated that kudzu root extracts have a hypocholesterolemic effect on rats fed diets high in fat and cholesterol. To further elucidate the mechanism involved, in this study we investigated the effect of water extracts of kudzu root, Pueraria radix, on the production of apolipoprotein B$_{100}$ (APo B$_{100}$) in HepG$_2$ liver cells and secretion of apolipoprotein B$_{48}$ (Apo B$_{48}$) in Caco$_2$ cells. Human cell lines, HepG$_2$ liver cells and Caco$_2$ intestinal epithelial cells, were grown with various concentrations (0%, 0.5%, 1.0%, 1.5%, 2.0%) of water extracts of kudzu root in the media. The kudzu root extract decreased Apo B$_{100}$ production and secretion. Treatment of HeP G$_2$ cells with the kudzu root extract also significantly decreased the intracellular total and free cholesterol concentration, and also decreased esterified cholesterol but was only significant at the highest dose of 2%. Apo B$_{48}$ production, but not secretion, from enterocytes was lowered by the kudzu root extracts. This research provided evidence that the hypocholesterolemic properties of kudzu root may be a consequence of decreased production and secretion of Apo B$_{100}$ in the liver and Apo B$_{48}$ in the intestine.

• Nutrition Research and Practice
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• 제8권3호
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• pp.257-266
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• 2014

BACKGROUND/OBJECTIVE: Licorice has been shown to possess cancer chemopreventive effects. However, glycyrrhizin, a major component in licorice, was found to interfere with steroid metabolism and cause edema and hypertension. The roasting process of licorice modifies the chemical composition and converts glycyrrhizin to glycyrrhetinic acid. The purpose of this study was to examine the anti-carcinogenic effects of the ethanol extract of roasted licorice (EERL) and to identify the active compound in EERL. MATERIALS/METHODS: Ethanol and aqueous extracts of roasted and un-roasted licorice were prepared. The active fraction was separated from the methylene chloride (MC)-soluble fraction of EERL and the structure of the purified compound was determined by nuclear magnetic resonance spectroscopy. The anti-carcinogenic effects of licorice extracts and licochalcone A was evaluated using a MTT assay, Western blot, flow cytometry, and two-stage skin carcinogenesis model. RESULTS: EERL was determined to be more potent and efficacious than the ethanol extract of un-roasted licorice in inhibiting the growth of DU145 and MLL prostate cancer cells, as well as HT-29 colon cancer cells. The aqueous extracts of un-roasted and roasted licorice showed minimal effects on cell growth. EERL potently inhibited growth of MCF-7 and MDA-MB-231 breast, B16-F10 melanoma, and A375 and A2058 skin cancer cells, whereas EERL slightly stimulated the growth of normal IEC-6 intestinal epithelial cells and CCD118SK fibroblasts. The MC-soluble fraction was more efficacious than EERL in inhibiting DU145 cell growth. Licochalcone A was isolated from the MC fraction and identified as the active compound of EERL. Both EERL and licochalcone A induced apoptosis of DU145 cells. EERL potently inhibited chemically-induced skin papilloma formation in mice. CONCLUSIONS: Non-polar compounds in EERL exert potent anti-carcinogenic effects, and that roasted rather than un-roasted licorice should be favored as a cancer preventive agent, whether being used as an additive to food or medicine preparations.

• Journal of Nutrition and Health
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• 제34권2호
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• pp.150-157
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• 2001

Intestinal absorption of dietary taurine is one of the regulatory component maintaining taurine homeostasis along with renal reabsorption, bile acid conjugation and secretion, and de nobo synthesis of taurine in mammals. Recent observations of decreased enterocytic levels of taurine in response to trauma, infection and surgical insults, postulate the possibility that intestinal taurine absorption might be impaired in such stressed conditions. The aim of the present study was to evaluate changes in enterocytic taurine transporter activity using the human intestinal colon carcinoma cell line, HT-29, in various stress-induced conditions. Pretreatment of the HT-29 cells with dexamethasone, a stress hormone(0.1,1,10 or 100$\mu$M) for 3 hrs, or with E coli heat-stable enterotoxin(10, 100, or 200nM) for 30 minutes in order to induce the condition of enterotoxigenic infection did not influence taurine uptake as compared to the value found in control cells. In contrast, pretreatment of the cells with cholera toxin(10, 100, 500, or 1000ng/ml)for 3hr or 24hr significantly decreased taurine uptake by HT-29 cells to 40~50% of the value found in untreated control cells. Kinetic studies of the taurine transporter activity were conducted in control and cholera toxin treated HT-29 cells with varying taurine concentrations(2~60$\mu$M) in the uptake medium. Pretreatment of the cells with cholera toxin(100ng/ml) for 3hr did not influence the Vmax, but resulted in a 55% increase in the Michaelis-Menten constant(Km) of the taurine transporter compared to those in control cells. These results suggest that cholera toxin-induced reduction in taurine transporter activity in HT-29 cells is associated with decreased affinity of the taurine transporter without altering the amount of transporter protein. Intestinal taurine absorption appears to be reduced in the condition of water-borne diseases caused by bacteria such as V. cholerae. This might influence the taurine status of infants and young children more readily, an age group in which the prevalence of intestinal infection is high and the role of intestinal absorption is crucial for maintaining the body taurine pool. (Korean J Nutrition 34(2) : 150-157, 2001)

• Preventive Nutrition and Food Science
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• 제19권3호
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• pp.129-135
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• 2014

The protective role of phloroglucinol against oxidative stress and stress-induced premature senescence (SIPS) was investigated in vitro and in cell culture. Phloroglucinol had strong and concentration-dependent radical scavenging effects against nitric oxide (NO), superoxide anions ($O_2{^-}$), and hydroxyl radicals. In this study, free radical generators were used to induce oxidative stress in LLC-PK1 renal epithelial cells. Treatment with phloroglucinol attenuated the oxidative stress induced by peroxyl radicals, NO, $O_2{^-}$, and peroxynitrite. Phloroglucinol also increased cell viability and decreased lipid peroxidation in a concentration-dependent manner. WI-38 human diploid fibroblast cells were used to investigate the protective effect of phloroglucinol against hydrogen peroxide ($H_2O_2$)-induced SIPS. Phloroglucinol treatment attenuated $H_2O_2$-induced SIPS by increasing cell viability and inhibited lipid peroxidation, suggesting that treatment with phloroglucinol should delay the aging process. The present study supports the promising role of phloroglucinol as an antioxidative agent against free radical-induced oxidative stress and SIPS.

• Preventive Nutrition and Food Science
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• 제8권2호
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• pp.113-118
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• 2003

We recently extracted lignans such as matairesinol and 2-hydroxyarctigenin from safflower seeds and found that they exhibit a potent cytotoxic effect on human promyleocytic leukemia HL-60 cells. In this study, we investigated whether mechanisms of the matairesinol-induced cell death are associated with the programmed cell death, apoptosis. Matairesinol dose-dependently reduced viability of HL-60 cells with an IC/sun 50/ value of 60 $\mu$M. Staining of cells with Hoechst 33342 revealed distinct morphological features of apoptosis, such as the nuclei broken into chromatin containing fragments of various sizes in the cells exposed to 100 $\mu$M matairesinol for 24 hr. Agarose gel electrophoresis of DNA from the cells treated with matairesinol showed internucleosomal DNA degradation into oligonucleosomal sizes. DNA ladder like patterns were easily detected after treatment with matairesinol concentrations ranging from 10 to 100 $\mu$M after 24 hr. In cells treated with 100 $\mu$M matairesinol for differing time periods, the DNA ladder was detectable from 6 hr onward. A time course histogram of the DNA content analyzed by flow cytometry revealed a rapid increase in subdiploid cells and a concomitant decrease in diploid cells exposed to 100 $\mu$M matairesinol. These results indicate that matairesinol-induced HL-60 cell death was due to the DNA damage and apoptosis.

• Preventive Nutrition and Food Science
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• 제12권2호
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• pp.79-83
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• 2007

The effects of young radish (YR, yeolmu in Korean) on the induction of apoptosis were examined in AGS human gastric adenocarcinoma cells. The young radish kimchi (YRK) were made of YR cultivated in the soil without (Control YR kimchi: C-YRK) and with 1,818 g/m$^{3}$ sulfur (Sulfur YR kimchi: S-YRK), respectively. Methanol extracts from S-YRK exhibited higher inhibitory effect on the growth of AGS human gastric adenocarcinoma cells in a time dependent-manner compared to C-YRK at the same concentration. 4,6-diamidino-2-phenylindole (DAPI) staining showed that S-YRK induced apoptosis accompanied by the increased Bax but decreased Bcl-2 in mRNA expression. Moreover, S-YRK decreased the levels of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) mRNA expressions. The results suggested that S-YRK cultivated in the presence of sulfur elicited stronger anticancer activity than C-YRK in vitro. Dietary intakes of S-YRK may be beneficial to decrease the risk of cancer.

• Biomolecules & Therapeutics
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• 제21권2호
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• pp.121-125
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• 2013

Hesperetin (3',5,7-trihydroxy 4'-methoxyflavanone) and its glycoside hesperidin (hesperetin 7-rhamnoglucoside) in oranges have been reported to possess pharmacological effects related to anti-obesity. However, hesperetin and hesperidin have not been studied on suppressive effects on appetite. This study examined that hesperetin and hesperidin can stimulate the release of cholecystokinin (CCK), one of appetite-regulating hormones, from the enteroendocrine STC-1 cells, and then examined the mechanisms involved in the CCK release. Hesperetin significantly and dose-dependently stimulated CCK secretion with an $EC_{50}$ of 0.050 mM and increased the intracellular $Ca^{2+}$ concentrations ($[Ca^{2+}]_i$) compared to the untreated control. The stimulatory effect by hesperetin was mediated via the entry of extracellular $Ca^{2+}$ and the activation of TRP channels including TRPA1. These results suggest that hesperetin can be a candidate biomolecule for the suppression of appetite and eventually for the therapeutics of obesity.

• 한국식품영양학회지
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• 제21권4호
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• pp.403-409
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• 2008

Elaeagnus multiflora, generally referred to as the cherry silverberry, is a plant. Elaeagnus multiflora fruit, leaves, and roots have been traditionally utilized in China as a treatment for cough, diarrhea, itch, and foul sores, and even cancer. More importantly, it is being investigated as a food that is capable of reducing the incidence of cancer, and also as a means of halting or reversing the growth of cancers. Considering the dearth of information regarding the medicinal properties of Elaeagnus multiflora, we assessed the antioxidative and cytotoxic effects of Elaeagnus multiflora by examining its scavenging effects on the 1,1-diphenyl-2-picryl-hydrazyl(DPPH) radical, its inhibitory effects on lipid peroxidation, and its inhibitory effects on cancer cell proliferation in HeLa cells, MCF-7 cells, and SNU-638 cells via MTT assay. Ethanol extracts of Elaeagnus multiflora flesh and seed inhibited DPPH radical production($36.91{\pm}1.00$, $94.17{\pm}0.37$) and lipid peroxidation ($28.18{\pm}5.02$, $40.30{\pm}1.45$, respectively). The Elaeagnus multiflora seed is believed to exert a possible antioxidative effects against the DPPH radical. The ethanol extracts of Elaeagnus multiflora flesh and seed exerted the cytotoxic effects on Hela cells ($6.93{\pm}1.92$, $84.97{\pm}0.47$), MCF-7 cells($5.45{\pm}0.41$, $84.97{\pm}0.47$), and SNU-638 cells($19.39{\pm}0.43$, $76.84{\pm}0.63$) used in this study. This result suggests that Elaeagnus multiflora seeds in contrast to its flesh, is believed to exert a possible anticancer effect. Elaeagnus multiflora seeds are considered to be a the candidate for preventative and dietetic treatment as an anticancer functional food.

• Journal of Nutrition and Health
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• 제52권2호
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• pp.176-184
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• 2019

Purpose: Protein overloading in the endoplasmic reticulum (ER) leads to endoplasmic reticulum stress, which exacerbates various disease conditions. Emodin, an anthraquinone compound, is known to have several health benefits. The effect of emodin against palmitic acid (PA) - induced ER stress in HepG2 cells was investigated. Methods: HepG2 cells were treated with varying concentrations of palmitic acid to determine the working concentration that induced ER stress. ER stress associated genes such as ATF4, XBP1s, CHOP and GRP78 were checked using RT- PCR. In addition, the expression levels of unfolded protein response (UPR) associated proteins such as $IRE1{\alpha}$, $eIF2{\alpha}$ and CHOP were checked using immunoblotting to confirm the induction of ER stress. The effect of emodin on ER stress was analyzed by treating HepG2 cells with $750{\mu}M$ palmitic acid and varying concentrations of emodin, then analyzing the expression of UPR associated genes. Results: It was evident from the mRNA and protein expression results that palmitic acid significantly increased the expression of UPR associated genes and thereby induced ER stress. Subsequent treatment with emodin reduced the mRNA expression of ATF4, GRP78, and XBP1s. Furthermore, the protein levels of $p-IRE1{\alpha}$, $p-eIF2{\alpha}$ and CHOP were also reduced by the treatment of emodin. Analysis of sirtuin mRNA expression showed that emodin increased the levels of SIRT4 and SIRT7, indicating a possible role in decreasing the expression of UPR-related genes. Conclusion: Altogether, the results suggest that emodin could exert a protective effect against fatty acid-induced ER stress and could be an agent for the management of various ER stress related diseases.