• Environmental Analysis Health and Toxicology
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• 제19권2호
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• pp.191-200
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• 2004

Zinc (Zn) is an essential element in biological process, however inadequate Zn status in general population have been recognized. To update the knowledge for Zn-cadmium (Cd) interaction, we studied the intestinal uptake and transport, and the expression of metal transporter proteins (divalent metal transporter 1, DMT1 ; metal transporter protein 1, MTP1 ; zinc transporter 1, ZnTl ; metallothionein 1 , MT1) in duodenum after Cd exposure using Zn deficient animal model. Rats were led Zn deficient (ZnD, 0.5-1.0 mgZn/kg) or Zn supplemented (ZnS, 50mg Zn/kg) diet for 4 weeks, and followed single administration of $^{109}$ CdCl$_2$orally. The body Zn flatus and tissue Cd concentration were determined at 24 hrs after Cd administration. Total body burden of Cd and Cd absorption index (AI, %) were estimated based on the tissue Cd analyzed. DMT1, MTP1, ZnTl and MT1 mRNA were analyzed by using RT-PCR method. Feeding of Zn deficient diet for 4 weeks produced a reduced body weight gain and a depletion of body Zn. Tissue Cd concentration, body burden of Cd and Cd absorption index were higher in the ZnD diet fed rats than the ZnS diet red rats. Especially, Cd concentration in the small intestine (duodenum, jejunum and ileum) and the colon of FeD diet fed rats were higher markedly than in the FeS diet group. The expression levels of DMT1, MTP1 and ZnT1 mRNA in FeD diet fed rats were similar to the FeS diet. The level of MT1 mRNA expression was significantly lower in the FeD than the FeS diet fed rats. Taken together, theses results indicate that Zn deficiency in diet induce an increased intestinal absorption and tissue retention of Cd, and down -regulate the MT1 expression in the intestine which might be play a part of role in Cd absorption and transport in mammalian. These findings suggest that deficiency of essential metal could be enhanced the toxicity of toxic, non-esstial metals through the metal-metal interaction.

• 대한임상검사과학회지
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• 제43권2호
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• pp.33-42
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• 2011

Zinc plays a key role in genetic expression, cell division, and cell growth and is essential for the functions of more than 450 metalloenzyme. There are high concentrations of zinc in pigment epithelium in bullfrog eye. Zinc deficiency causes night blindness and abnormal dark adaptation. The purpose of this study was to identify ERG (electroretinogram) b-wave sensitivity during light and dark adaptation in bullfrog retina after zinc and zinc chelators treatment such as histidine and TSQ (N-(6-methoxy-8-qunolyl)-p-toluenesulfon amide). Especially, we focused whether histidine act as a zinc chelator in the Muller cell. The results of our study are summarized as follows: 1) Both zinc and histidine elevated ERG b-wave amplitude and threshold in Muller cells by accelerating rhodopsin regeneration time and increased a-peak absorbance during light adaptation. 2) TSQ reduced those by prolonging rhodopsin regeneration time and decrement of a-peak absorbance during light adaptation. 3) Zinc shortened rhodopsin regeneration time and prolonged a-peak absorbance. These results suggested that histidine may act as a zinc-mediated transporter in presynaptic Muller cell membrane rather than zinc chelator and acts as a GABA-receptor inhibitor which blocks $Cl^-$ influx to the postsynapse.

• Preventive Nutrition and Food Science
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• 제22권1호
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• pp.1-8
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• 2017

About 20 chemical elements are nutritionally essential for humans with defined molecular functions. Several essential and nonessential biometals are either functional nutrients with antidiabetic actions or can be diabetogenic. A key question remains whether changes in the metabolism of biometals and biominerals are a consequence of diabetes or are involved in its etiology. Exploration of the roles of zinc (Zn) in this regard is most revealing because 80 years of scientific discoveries link zinc and diabetes. In pancreatic ${\beta}$- and ${\alpha}$-cells, zinc has specific functions in the biochemistry of insulin and glucagon. When zinc ions are secreted during vesicular exocytosis, they have autocrine, paracrine, and endocrine roles. The membrane protein ZnT8 transports zinc ions into the insulin and glucagon granules. ZnT8 has a risk allele that predisposes the majority of humans to developing diabetes. In target tissues, increased availability of zinc enhances the insulin response by inhibiting protein tyrosine phosphatase 1B, which controls the phosphorylation state of the insulin receptor and hence downstream signalling. Inherited diseases of zinc metabolism, environmental exposures that interfere with the control of cellular zinc homeostasis, and nutritional or conditioned zinc deficiency influence the pathobiochemistry of diabetes. Accepting the view that zinc is one of the many factors in multiple gene-environment interactions that cause the functional demise of ${\beta}$-cells generates an immense potential for treating and perhaps preventing diabetes. Personalized nutrition, bioactive food, and pharmaceuticals targeting the control of cellular zinc in precision medicine are among the possible interventions.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제11권2호
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• pp.122-129
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• 2008

목 적: 만성 설사, 흡수 장애 등의 소화기 질환에서 경구 영양 공급이 불충분할 경우 미량원소 결핍 발생의 빈도가 높으나, 이러한 환아에서 미량원소 결핍 증상에도 불구하고 혈액 검사 결과 정상으로 나타나기도 한다. 따라서 미량원소 결핍 고위험군 환아에서 결핍된 미량원소를 확인하고, 적절한 공급 및 추적 관찰 지표로서 모발 검사의 유용성을 알아보고자 하였다. 방 법: 서울대학교 어린이병원에 내원하여 만성 소화기 질환으로 경구 영양 장애 또는 성장 발육 부전을 보였던 13명을 대상으로 모발과 혈액의 미량원소 검사를 시행하여, 결핍 소견을 보인 모발과 혈액의 미량원소에 대해 장기 정맥영양군과 경구영양군, 그리고 증상군과 무증상군으로 나누어 비교, 분석하였다. 결 과: 전체 13명 중 11명에서 모발 또는 혈액 검사에서 미량원소 결핍이 있었으며, 결핍된 미량원소는 아연, 셀레늄, 구리였다. 모발 내 아연 결핍은 8명(62%), 모발 내 셀레늄 결핍은 6명(46%)이었고, 혈액 내 아연농도가 정상인 환자의 67% (8/12명), 혈액 내 셀레늄 농도가 정상 환자의 57% (4/7명)에서 각각 모발 내 아연, 모발 내 셀레늄 결핍을 보였다. 모발 내 아연 농도는 장기 정맥영양군에서 경구영양군에 비해 유의하게 낮았으며(p=0.015) 결핍 발생 빈도 또한 유의하게 높았다(Fisher's exact test, p=0.032). 모발 내 셀레늄 농도는 증상군에서 무증상군에 비해 유의하게 낮았다(p=0.034). 결 론: 만성 소화기 질환으로 경구 영양 장애 또는 성장 발육 부전이 있을 경우 증상 여부에 상관없이 혈액검사와 함께 모발 미네랄 검사로 결핍 여부를 평가하는 것이 필요할 것으로 보인다.

• 대한영양사협회학술지
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• 제7권3호
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• pp.258-266
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• 2001

The purpose of this study was to investigate the effect of dietary zinc on the carbohydrate metabolism and the serum content of magnesium and chromium in rats fed normal diet. Animals were divided into three groups by different dietary zinc levels which were low(15ppm), normal(30ppm) or high(60ppm). Serum glucose and Insulin concentrations were assessed by the glucose method and the radio immuno assay respectively. Serum zinc. magnesium and chromium contents were measured by Indectively Coupled Plasma(ICP). Results of the study were as follows : 1. Feed intake in a zinc deficiency group was significantly higher than that in other group, but the weight gain in high zinc diet group was significantly lower than in other groups. 2. There were no significant differences in liver, kidney and spleen weight. 3. Serum glucose, insulin and zinc concentrations were not significantly different among different dietary zinc groups, However serum magnesium and chromium concentrations were significantly decreased as the level of dietary zinc was increased.

• Journal of Nutrition and Health
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• 제21권2호
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• pp.113-121
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• 1988

The purpose of this study was to investigate the effects of dietary zinc on immune response in mice. Weanling male mice was placed individually in stainless steel cages and fed a zinc dificient diet and control diet. All mice were given deionized water ad libitum. The introduction of extraneous zinc was minimized in all cage by washing feed jars and water bottles sequentially with 4mM EDTA and conc-nitiric acid followed by deionized water. After 4 and 5 weeks of the diets, mice were immunized with lx 106 Naegleria fowleri intraperitoneally. Mice were weighed once a week. The results from this study are summarized as followed ; 1) Mice fed the zinc dificient diet showed growth retardation. After 3 weeks of diets, mean body weight of zinc deficient mice was 21.4g and that of control was 25.0g. This difference is singnificant statistically (p<0.01). The more time passed, the more remarkable difference was found. 2) The weigth of organs were measured on liver, kidney, spleen, thymus, heart, lung, brain. Difference in weight were observed only in liver and spleen. 3) Proliferative response of spleen cells of zinc deficient mice to con A was lower than that of control mice after one week on immunization(p<0.005). 4) Stimulation index was lower in zinc deficient mice to phytohemagglutinin after two weeks on immunization (p<0.05). 5) Blastogenesis of speen cells of zinc deficient mice to Naegleria fowleric lysate was lower after 10 days on immunization (p<0.05). 6) Immunoglobulin G antribody titers of zinc deficient mice sera by ELISA was lowered to control mice after 5 weeks on immunization (p<0.005).

• 한국영양학회:학술대회논문집
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• 한국영양학회 2003년도 연합학술대회
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• pp.132.1-132.1
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• 2003

• Journal of Veterinary Science
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• 제24권1호
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• pp.3.1-3.13
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• 2023

Background: Zinc (Zn) is an essential cofactor for physiological homeostasis in the body. Zn oxide (ZnO), an inorganic compound that supplies Zn, exists in various sizes, and its bioavailability may vary depending on the size in vivo. However, comparative studies on the nutritional effects of micro-sized ZnO (M-ZnO) and nano-sized ZnO (N-ZnO) supplementation on Zn deficiency (ZnD) animal models have not been reported. Objectives: This study investigated the nutritional bioavailability of N-ZnO and M-ZnO particles in dietary-induced ZnD mice. Methods: Animals were divided into six experimental groups: normal group, ZnD control group, and four ZnO treatment groups (Nano-Low, Nano-High, Micro-Low, and MicroHigh). After ZnD induction, N-ZnO or M-ZnO was administered orally every day for 4 weeks. Results: ZnD-associated clinical signs almost disappeared 7 days after N-ZnO or M-ZnO administration. Serum Zn concentrations were higher in the Nano-High group than in the ZnD and M-ZnO groups on day 7 of ZnO treatment. In the liver and testis, Nano-Low and Nano-High groups showed significantly higher Zn concentrations than the other groups after 14-day treatment. ZnO supplementation increased Mt-1 mRNA expression in the liver and testis and Mt-2 mRNA expression in the liver. Based on hematoxylin-and-eosin staining results, N-ZnO supplementation alleviated histological damage induced by ZnD in the testis and liver. Conclusions: This study suggested that N-ZnO can be utilized faster than M-ZnO for nutritional restoration at the early stage of ZnD condition and presented Mt-1 as an indicator of Zn status in the serum, liver, and testis.

• 한국식품영양과학회지
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• 제28권2호
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• pp.464-470
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• 1999

The purpose of this study was to investigate the effect of zinc intake on immune responses in high fat diet induced obese rats. The immune status was assessed by the measurements of immunoglobulins (IgG, A, and M) production by SRBC(sheep red blood cell) with mitogen in vivo. The delayed type hypersensitivity(DTH) response was also measured as an index of cell mediated immunity. The re sults are summarized as follows : 1) There were no significant differences in the feed intake, weight gain and feed efficiency ratio of obese rats by the different dietary zinc levels. 2) White blood cell (WBC) counts were significantly affected as the dietary zinc levels decreased. The capacity of Ig M production in obese rats was significantly higher in normal zinc group than that of low and high zinc group. Cell mediated immune response evaluated by means of DTH testing has also been found to be highly impaired by zinc deficiency and overload. From these observations, it was suggested that adequate levels of zinc may promote the immune function of obese individuals. The relationship and its functional role of the zinc in obesity remains to be further studied.

• Nutrition Research and Practice
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• 제17권2호
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• pp.257-268
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• 2023

BACKGROUND/OBJECTIVES: Zinc is an essential trace mineral which is important for the growth and development of the human body and immunological and neurological functions. Inadequate zinc intake may cause zinc deficiency with its adverse consequences. In this study, we aimed to estimate the dietary zinc intake levels and sources among Koreans. SUBJECTS/METHODS: For this secondary analysis, we obtained data from the Korea National Health and Nutrition Examination Survey (KNHANES) 2016-2019. Individuals aged ≥ 1 yr who had completed a 24-h recall were included. The dietary zinc intake of each individual was calculated by applying data from a newly developed zinc content database to the KNHANES raw data. We also compared the extracted data with the sex-, age-specific reference values suggested in the Korean Dietary Reference Intakes 2020. The prevalence of adequate zinc intake was then evaluated by the proportion of the individuals who met the estimated average requirement (EAR). RESULTS: The mean zinc intake of Koreans aged ≥ 1 yr and adults aged ≥ 19 yrs were 10.2 and 10.4 mg/day, equivalent to 147.4% and 140.8% of the EAR, respectively. Approximately 2 in 3 Koreans met the EAR for zinc, but the zinc intake differed slightly among the different age and sex groups. In children aged 1-2 yrs, 2 out of 5 exceeded the upper level of intake, and nearly half of the younger adults (19-29 yrs) and the elders (≥ 75 yrs) did not meet the EAR. The major contributing food groups were grains (38.9%), meats (20.4%), and vegetables (11.1%). The top 5 food contributors to zinc intake were rice, beef, pork, egg, and baechu kimchi, which accounted for half of the dietary intake. CONCLUSION: The mean zinc intake among Koreans was above the recommended level, but 1 in 3 Koreans had inadequate zinc intake and some children were at risk of excessive zinc intake. Our study included zinc intake from diet only, thus to better understand zinc status, further research to include intake from dietary supplements is needed.