Effect of Lipids Containing Conjugated Linoleic Acids on Proliferation and Differentiation of Preadipocytic Cells

Jin-Joo Hue, Yea-Eun Lee, Jae-Hwang Jeong, Sang-Hwa Lee, Young Ho Lee, Soon Ki Hong, Seong-Woon Jeong, Sang Woon Nam, Young Won Yun, Beom Jun Lee 충북대학교 동물의학연구소 2007 Journal of Biomedical and Translational Research Vol.8 No.1

본문참고

Aflatoxin M1 in Pasteurized Market Milk in Korea

Hwang, Kyu-Choon,Hwang, Joo-Yea,Kim, Hyoun-Wook,Oh, Mi-Hwa Korean Society for Food Science of Animal Resource 2012 한국축산식품학회지 Vol.32 No.3

Aflatoxin M1, ingested as aflatoxin B1 via contaminated feedstuff and later converted into, is a major problematic target for milk safety control among the aflatoxin class. Korean government has controlled level of AFM1 in milk at 500 ppt as maximum residue level (MRL), and more recently, government also publicized the proposal for more strict control on fungal toxins about infant and baby foods. In this study the levels of Aflatoxin M1 (AFM1) of 42 marketed milk samples were determined with Enzyme-Linked Immunosorbent Assay (ELISA) to evaluate the status on the contamination of Aflatoxin M1. The evaluated ELISA performances of limit of detection (LOD) and the half maximal inhibitory concentration ($IC_{50}$) were 5 pg/mL (ppt) and 49 ppt, respectively. In all 42 samples, AFM1 appeared above the 5 ppt, with the average of 21 ppt and the range of up to 90 ppt. Only 3 (7%) of samples showed the level of contamination above the EU MRL (50 ppt). Although there was incidence of higher level of contamination compared with previous reports, the result of this study requires more intensive study to control of AFM1 in milk and infant foods.

Phytic Acid Increases the Formation of Colonic Aberrant Crypt Foci in Male F344 Rats with Iron-Deficient Status

Yea Eun Lee,Jin-Joo Hue,Ki-Nam Lee,Sang Yoon Nam,Byeongwoo Ahn,Young Won Yun,Jae-Hwang Jeong,Beom Jun Lee 한국실험동물학회 2008 Laboratory Animal Research Vol.24 No.3

Iron is essential for life and has numerous biochemical roles. Phytic acid (PA) has been recognized as a natural antioxidant by its chelating properties and reducing the catalytic activities of many divalent transition metals. We investigated the effect of PA on the formation of aberrant crypt foci (ACF) induced by azoxymethane (AOM) in dietary iron-deficient F344 rats. After acclimation for one week, six-week old F344 male rats were fed with the AIN-93G purified diet (normal diet) or an iron-deficient diet (3 ppm Fe, only 10% vs control diet) for 8 weeks. PA (0.5% or 2% PA in water) was given for drink throughout the experimental period. Animals were treated subcutaneously with AOM (15 ㎎/㎏) twice (1<SUP>st</SUP> and 2<SUP>nd</SUP> week of the experiment) to induce colonic ACF. After sacrifice, the colonic mucosa were examined for the total numbers of aberrant crypt (AC) and ACF after staining with methylene blue. The blood and serum were analyzed with a blood cell differential counter and an automatic serum analyzer. Iron-deficient diet induced an anemic status of rats as indicated by significantly low values in RBC count, hemoglobin, hematocrit, mean corpuscular volume, and mean corpuscular hemoglobin, compared with the AOMtreated control (P<0.01). However, treatments of PA increased these values. Treatment with 2% PA significantly increased the numbers of both ACF/colon and AC/colon in iron deficient rats, compared with the respective control (P<0.05). The number of large ACF (≥4 AC/ACF), which had been suggested to possess a greater tumorogenic potential than small ACF (≤3 AC/ACF), was significantly enhanced by treatment with 2% PA (P<0.05). These results suggest that PA may promote colon carcinogenesis in irondeficient status in rats.

Phytic acid does not affect the formation of colonic aberrant crypt foci in Fe-overloaded male F344 rats

Lee, Yea Eun,Hue, Jin-Joo,Lee, Ki-Nam,Nam, Sang Yoon,Ahn, Byeongwoo,Yun, Young Won,Jeong, Jae-Hwang,Lee, Beom Jun The Korean Society of Veterinary Science 2008 大韓獸醫學會誌 Vol.48 No.3

There are accumulating evidences that high levels of dietary iron may play a role in colon carcinogenesis. Elevated iron status has been associated with oxidative stress. Phytic acid (PA) functions as an antioxidant by chelating divalent cations and prevents formation of reactive oxygen species responsible for cell injury and carcinogenesis. The protective effect of PA was investigated on formation of aberrant crypt foci (ACF) induced by azoxymethane (AOM) in iron-overloaded male F344 rats. After acclimation with AIN-93G purified diet (35 ppm Fe, normal control diet) for one week, animals were fed iron-overloaded diet (350 ppm Fe) and PA (0.5% or 2% PA in water) for 8 weeks. Animals received two (1st and 2nd week) injections of AOM (15 mg/kg b.w.) to induce colonic ACF. The colonic mucosa was examined for the total numbers of aberrant crypt (AC) and ACF after staining with methylene blue. The blood and serum were analyzed with a blood cell differential counter and an automatic serum analyzer. Iron-overloaded diet increased the concentration of iron in liver of the rats. But iron-related parameters in blood were not changed among experimental groups. The numbers of ACF per colon and AC per colon were $178.8{\pm}33.2$ and $448.4{\pm}110.2$ in the iron-overloaded F344 rats. The total AC was significantly increased, compared with normal-diet AOM control group (p < 0.05). The treatments of PA at the dose of 0.5% slightly decreased the number of ACF and AC per colon to $153.6{\pm}29.5$ and $396.3{\pm}107.5$. However, there were no significant differences in the total numbers of ACF and AC between the AOM control group and PA (0.5% or 2%)-treated groups. These results suggest that PA may not affect the formation of ACF or AC induced by AOM in ironoverloaded F344 rats.

Effects of Diglyceride-Conjugated Linoleic Acid on Proliferation and Differentiation of 3T3-L1 Cells

Jae-Hwang Jeong,Sang-Hwa Lee,Jin-Joo Hue,Yea Eun Lee,Young Ho Lee,Soon Ki Hong,Seong-woon Jeong,Sang Yoon Nam,Young Won Yun,Beom Jun Lee 한국독성학회 2007 Toxicological Research Vol.23 No.3

Conjugated linoleic acid (CLA) has been recently reported to have an anti-obesity effect in animals and humans. The objective of this study was to investigate effects of diglyceride (DG)-CLA on proliferation and differentiation of 3T3-L1 preadipocytes. Cell proliferation was determined using WST-8 analysis and cell differentiation was determined by glycerol-3-phosphate dehydrogenase (GPDH) activity. Lipid accumulation in differentiating 3T3-L1 cells was determined by Oil red O staining. There were four experimental groups including vehicle control (DMSO), CLA, triglyceride (TG)-CLA, and DG-CLA. Treatments of CLA, TG-CLA, and DG-CLA at the concentrations of 10~1000 ㎍/㎖ reduced proliferation of preconfluent 3T3-L1 cells in a dose-dependent manner. Among them CLA was the most effective in the proliferation inhibition of preconfluent 3T3-L1 cells with increasing concentrations. Treatments of CLA and DG-CLA at the concentration of 100 ㎍/㎖ significantly inhibited differentiation of postconfluent 3T3-L1 cells as measured by GPDH activity (p<0.05). In addition, treatments of CLA, TG-CLA, and DG-CLA effectively inhibited lipid accumulation during differentiation of 3T3-L1 cells. DG-CLA had the most inhibitory effect on the differentiation and lipid accumulation. These results suggest that the compounds including CLA have a respectable anti-obesity effect and that consumption of DG-CLA as a dietary oil may give a benefit for controlling overweight in humans.

Protective Effect of Carnosine Against Zn-Mediated Toxicityin Cortical Neuronal Cells

Jin-Joo Hue,Ah-Ram Lee,Yea Eun Lee,Min-Hang Cho,Ki-Nam Lee,남상윤,윤영원,Jae-Hwang Jeong,Sang-Hwa Lee,이범준 한국독성학회 2007 Toxicological Research Vol.23 No.1

Zinc is an endogenous transition metal that can be synaptically released during neuronal activity. However, zinc may contribute to the neuropathology associated with a variety of conditions. Carnosine expressed in glial cells can modulate the effects of zinc on neuronal excitability as a zinc chelator. We hypothesize that carnosine may protect against neurotoxicity of zinc in cortical neuronal cells. The cortical neuronal cells from newborn rats were prepared and exposed to zinc chloride and/or carnosine at various concentrations. Zinc at the doses of 0 to 500 μM decreased neuronal cell viability in a dosedependent manner. Additionally, at the concentrations of 100 and 200 μM, it significantly decreased cell viability in an exposed time-dependent manner (p < 0.05). Treatment with carnosine at the concentrations of 20 and 200 μM significantly increased neuronal cell proliferation by approximately 14% and 20%, respectively, compared to the control (p < 0.05). At the concentrations of 100 and 200 μM zinc, 20 μM carnosine significantly increased the viability of neuronal cells by 18.3% and 12.1%, and 200 μM carnosine also increased it by 33.5% and 28.6%, respectively, compared to the normal control group (p < 0.01). These results suggest that carnosine at a physiologically relevant level may protect against zinc-mediated toxicity in neuronal cells as an endogenous neuroprotective agent

Comparison of Diglyceride, Conjugated Linoleic Acid, andDiglyceride-Conjugated Linoleic Acid on Proliferation andDifferentiation of 3T3-L1 Preadipocytes

Jae-Hwang Jeong,Sang-Hwa Lee,Jin-Joo Hue,Yea Eun Lee,Young Ho Lee,Soon Ki Hong,Seong-woon Jeong,남상윤,윤영원,이범준 한국식품위생안전성학회 2007 한국식품위생안전성학회지 Vol.22 No.3

Conjugated linoleic acid (CLA) reduces fat deposition in several mamalian species. The proposedmechanisms for this effect are reduced preadipocyte proliferation and diferentiation. The objective of this study wasto investigate the inhibitory efects of diglyceride (DG), CLA, DG-CLA of proliferation and diferentiation of 3T3-L1preadipocytes. Cel viability was determined using WST-8 analysis and cell diferentiation was determined by glyc-erol-3-phosphate dehydrogenase (GPDH) activity. Lipid acumulation in diferentiating 3T3-L1 cels was measuredreduced in a dose-dependent maner. CLA among them was the most effective in reduction of viable cels withincreasing concentrations. Treatments of the DG, CLA, and DG-CLA at the concentration of 10 g/ml for 48 h sig-nificantly inhibited differentiation of 3T3-L1 cels (p<0.05). In addition, cytoplasmic lipid accumulation during dif-ferentiation of the 3T3-L1 preadipocytes was also inhibited by treatments of the test solutions. DG-CLA was the mosteffective in the inhibition of diferentiation and lipid accumulation in 3T3-L1 cells. These results indicate that the DGCLA as a dietary oil may give a benefit for controlling overweight in humans.

Aflatoxin M1 in Pasteurized Market Milk in Korea

황규춘,Joo Yea Hwang,김현욱,오미화 한국축산식품학회 2012 한국축산식품학회지 Vol.32 No.3

Aflatoxin M1, ingested as aflatoxin B1 via contaminated feedstuff and later converted into, is a major problematic target for milk safety control among the aflatoxin class. Korean government has controlled level of AFM1 in milk at 500 ppt as maximum residue level (MRL), and more recently, government also publicized the proposal for more strict control on fungal toxins about infant and baby foods. In this study the levels of Aflatoxin M1 (AFM1) of 42 marketed milk samples were determined with Enzyme-Linked Immunosorbent Assay (ELISA) to evaluate the status on the contamination of Aflatoxin M1. The evaluated ELISA performances of limit of detection (LOD) and the half maximal inhibitory concentration (IC50)were 5 pg/mL (ppt) and 49 ppt, respectively. In all 42 samples, AFM1 appeared above the 5 ppt, with the average of 21 ppt and the range of up to 90 ppt. Only 3 (7%) of samples showed the level of contamination above the EU MRL (50 ppt). Although there was incidence of higher level of contamination compared with previous reports, the result of this study requires more intensive study to control of AFM1 in milk and infant foods.

Antibacterial activity of sodium phytate, sodium pyrophosphate, and sodium tripolyphosphate against Salmonella typhimurium in meats

Hue, Jin-Joo,Baek, Dong-Jin,Lee, Yea Eun,Lee, Ki Nam,Nam, Sang Yoon,Yun, Young Won,Jeong, Jae-Hwang,Lee, Sang-Hwa,Yoo, Han Sang,Lee, Beom Jun The Korean Society of Veterinary Science 2007 大韓獸醫學會誌 Vol.47 No.4

The approval of use of certain food-grade phosphates as food additives in a wide variety of meat products greatly stimulated research on the applications of phosphates in foods. Although phosphates have never been classified as antimicrobial agents, a number of investigators have reported that phosphates have antimicrobial activities. Phytic acid is a natural plant inositol hexaphosphate constituting 1-5% of most cereals, nuts, legumes, oil seeds, pollen, and spores. In this study, we investigated antibacterial activities of sodium phytate (SPT), sodium pyrophosphate (SPP), sodium tripolyphosphate (STPP) on Salmonella typhimurium in tryptic soy broth and in row meat media including chicken, pork and beef. SPY, SPP and STPP at the concentrations of 0.5 and 1% dose-dependently inhibited the growth of S. typhimurium in tryptic soy broth at various pHs. The antibacterial activities of SPT and STPP were the stronger than that of SPP. In chicken, pork, and beef, SPT, SPP and STPP at the concentrations of 0.1, 0.5 and 1.0% significantly inhibited the bacterial growth in a dose-dependant manner (p < 0.05). The antibacterial activities of SPT, SPP, and STPP were more effective in chicken than beef. SPT and STPP at the concentration of 1% reduced the bacterial count by about 2 log units. The addition of SPT, SPP and STPP at the concentration of 0.5% in meats increased the meat pHs by 0.28-0.48 units in chicken, pork, and beef. These results suggest that SPT and STPP were equally effective for the inhibition of bacterial growth both in TSB and meat media and that SPT can be used as an animal food additive for increasing shelf-life and functions of meats.

Effects of Diglyceride-Conjugated Linoleic Acid on Proliferation and Differentiation of 3T3-L1 Cells

Jeong, Jae-Hwang,Lee, Sang-Hwa,Hue, Jin-Joo,Lee, Yea-Eun,Lee, Young-Ho,Hong, Soon-Ki,Jeong, Seong-Woon,Nam, Sang-Yoon,Yun, Young-Won,Lee, Beom-Jun Korean Society of ToxicologyKorea Environmental Mu 2007 Toxicological Research Vol.23 No.3

Conjugated linoleic acid (CLA) has been recently reported to have an anti-obesity effect in animals and humans. The objective of this study was to investigate effects of diglyceride (DG)-CLA on proliferation and differentiation of 3T3-L1 preadipocytes. Cell proliferation was determined using WST-8 analysis and cell differentiation was determined by glycerol-3-phosphate dehydrogenase (GPDH) activity. Lipid accumulation in differentiating 3T3-L1 cells was determined by Oil red O staining. There were four experimental groups including vehicle control (DMSO), CLA, triglyceride (TG)-CLA, and DG-CLA. Treatments of CLA, TG-CLA, and DG-CLA at the concentrations of $10{\sim}1000{\mu}g/ml$ reduced proliferation of preconfluent 3T3-L1 cells in a dose-dependent manner. Among them CLA was the most effective in the proliferation inhibition of preconfluent 3T3-L1 cells with increasing concentrations. Treatments of CLA and DG-CLA at the concentration of $100{\mu}g/ml$ significantly inhibited differentiation of postconfluent 3T3-L1 cells as measured by GPOH activity (p<0.05). In addition, treatments of CLA, TG-CLA, and DG-CLA effectively inhibited lipid accumulation during differentiation of 3T3-L 1 cells. OG-CLA had the most inhibitory effect on the differentiation and lipid accumulation. These results suggest that the compounds including CLA have a respectable anti-obesity effect and that consumption of DG-CLA as a dietary oil may give a benefit for controlling overweight in humans.