• Molecular & Cellular Toxicology
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• 제3권4호
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• pp.292-298
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• 2007

Zinc plays indispensable roles in metabolism, including cell growth, apoptosis, proliferation and differentiation. Kidneys are target organs for various regulators of mineral metabolism, and play a key role in zinc balance. To investigate the zinc uptake efficiency, we examined the zinc uptake and accumulation level in vivo and in vitro study. Plasma zinc concentration was peaked out at 1 hr after oral zinc administration. The renal zinc level was peaked out at 12 hr after oral zinc administration, and it was the highest in 40 mg/kg Zn-Asp administrated group in comparison with other groups. In addition, the m-RNA expression level of zinc transporter-1 (ZnT-1), zinc transporter-2 (ZnT-2) and high-affinity L-aspartate transporter (EAAT-3) in Zn-Asp administered group were increased compared with control groups and $ZnSO_4$ group. In order to investigate the intracellular zinc uptake mechanism, we performed the in vitro study by using human embryonic kidney cell line, HEK 293. Intracellular zinc level was peaked out at 3 hr after zinc treatment. In the same way, the mRNA expression level of ZnT-1 and EAAT-3 were increased compared with control group. This study showed that Zn-Asp is effective the zinc uptake into the kidney by increasing the zinc transporter expression.

• Asian Pacific Journal of Cancer Prevention
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• 제16권8호
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• pp.3355-3360
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• 2015

Background: Zinc transporters have been considered as essential regulators in many cancers; however, their mechanisms remain unknown, especially in gliomas. Isocitrate dehydrogenase 1(IDH1) mutation is crucial to glioma. This study aimed to investigate whether zinc transporters are correlated with glioma grade and IDH1 mutation status. Materials and Methods: IDH1 mutation status and mRNA expression of four zinc transporters (ZIP4, ZIP9, ZIP11, and ZnT9) were determined by subjecting a panel of 74 glioma tissue samples to quantitative real-time PCR and pyrosequencing. The correlations between the expression levels of these zinc transporter genes and the grade of glioma, as well as IDH1 mutation status, were investigated. Results: Among the four zinc transporter genes, high ZIP4 expression and low ZIP11 expression were significantly associated with higher grade (grades III and IV) tumors compared with lower grade (grades I and II) counterparts (p<0.0001). However, only ZIP11 exhibited weak correlation with IDH1 mutation status (p=0.045). Samples with mutations in IDH1 displayed higher ZIP11 expression than those without IDH1 mutations. Conclusions: This finding indicated that zinc transporters may interact with IDH1 mutation by direct modulation or action in some shared pathways or genes to promote the development of glioma. Zinc transporters may play an important role in glioma. ZIP4 and ZIP11 are promising molecular diagnostic markers and novel therapeutic targets. Nevertheless, the detailed biological function of zinc transporters and the mechanism of the potential interaction between ZIP11 and IDH1 mutation in gliomagenesis should be further investigated.

• 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.

• Molecular & Cellular Toxicology
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• 제3권2호
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• pp.132-136
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• 2007

Zinc is essential metal and plays a role in a wide variety of physiological and biochemical processes. Prostate gland contains high level of zinc, generally 3-10 folds higher than other organs. Prostatic zinc uptake is resulted from the existence of zinc transporter (ZnT) protein families in membrane. In this study, we investigated the difference of zinc uptake efficiency of zinc-aspartate complex (Zn-Asp) into various organs compared with $ZnSO_4$. We observed that Plasma zinc concentration in both $ZnSO_4$ and Zn-Asp administrated group was increased progressively following administration, and reached a peak level at 2 hr. The increasing pattern of zinc concentration was similar to each groups, however the zinc concentration of Zn-Asp administrated group was higher than that of $ZnSO_4$ administrated group. We found that prostatic zinc level of Zn-Asp administrated group was higher than $ZnSO_4$ administrated group, and was increased approximately $\sim$2.7 fold and $\sim$4.2 fold at 4 and 8 hr after administration. From these observations, we suggest than Zn-Asp has high uptake efficiency of zinc into the prostate gland. Therefore, Zn-Asp is potentially useful treatment of many prostatic diseases.

• Journal of Microbiology and Biotechnology
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• 제18권2호
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• pp.242-247
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• 2008

In the fungal pathogen Candida albicans, the yeast-to-hyphal transition occurs in response to a broad range of environmental stimuli and is considered to be a major virulence factor. To address whether the zinc homeostasis affects the growth or pathogenicity of C. albicans, we functionally characterized the zinc-finger protein Csr1 during filamentation. The deduced amino acid sequence of Csr1 showed a 49% similarity to the zinc-specific transcription factor, Zap1 of Saccharomyces cerevisiae. Sequential disruptions of CSR1 were carried out in diploid C. albicans. The csr1/csr1 mutant strain showed severe growth defects under zinc-limited growth conditions and the filamentation defect under hypha-inducing media. The colony morphology and the germ-tube formation were significantly affected by the csr1 mutation. The expression of the hyphae-specific gene HWP1 was also impaired in csr1/csr1 cells. The C. albicans homologs of ZRTl and ZRT2, which are zinc-transporter genes in S. cerevisiae, were isolated. High-copy number plasmids of these genes suppressed the filamentation defect of the csr1/csr1 mutant strain. We propose that the filamentation phenotype of C. albicans is closely associated with the zinc homeostasis in the cells and that Csr1 plays a critical role in this regulation.

• Journal of Nutrition and Health
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• 제54권6호
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• pp.594-602
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• 2021

본 연구는 고지방식이로 유도한 비만 동물모델에서 아연의 식이를 통한 보충 급여가 혈당 조절과 골격 근육의 ZIP7의 작용에 미치는 영향에 대해 살펴보았다. 고지방식이를 공급한 HF군은 정상 대조군에 비하여 단위 체중당 골격 근육 무게가 유의하게 감소하였으며, 혈당은 유의적으로 증가하였다. 고지방식이와 함께 아연을 보충 공급한 HF+Zn군은 아연을 보충하지 않은 HF군과 비교하여, 공복 혈당과 경구 포도당 부하 후 혈당 증가 면적이 유의하게 감소하였다. 또한, HF+Zn군은 HF군에 비해 골격 근육의 ZIP7 단백질 수준이 유의하게 증가하였으며, AKT 활성과 GLUT4 단백질 수준도 유의하게 증가하는 것으로 나타났다. 이상의 결과를 종합해 볼 때, 아연 보충은 비만으로 인한 고혈당 증세를 완화하는 효과를 나타내며, 이는 골격 근육에서의 ZIP7 아연 수송체에 의한 당 대사 조절과 관련이 있을 것으로 생각된다.

• Molecules and Cells
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• 제43권4호
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• pp.323-330
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• 2020

Epigenetic events like DNA methylation and histone modification can alter heritable phenotypes. Zinc is required for the activity of various epigenetic enzymes, such as DNA methyltransferases (DNMTs), histone acetyltransferases (HATs), histone deacetylases (HDACs), and histone demethylases, which possess several zinc binding sites. Thus, the dysregulation of zinc homeostasis can lead to epigenetic alterations. Zinc homeostasis is regulated by Zinc Transporters (ZnTs), Zrt- and Irt-like proteins (ZIPs), and the zinc storage protein metallothionein (MT). Recent advances revealed that ZIPs modulate epigenetics. ZIP10 deficiency was found to result in reduced HATs, confirming its involvement in histone acetylation for rigid skin barrier formation. ZIP13 deficiency, which is associated with Spondylocheirodysplastic Ehlers-Danlos syndrome (SCD-EDS), increases DNMT activity, leading to dysgenesis of dermis via improper gene expressions. However, the precise molecular mechanisms remain to be elucidated. Future molecular studies investigating the involvement of zinc and its transporters in epigenetics are warranted.

• Mycobiology
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• 제43권3호
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• pp.179-183
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• 2015

Zinc is an essential micronutrient required for many enzymes that play essential roles in a cell. It was estimated that approximately 3% of the total cellular proteins are required for zinc for their functions. Zinc has long been considered as one of the key players in host-pathogen interactions. The host sequesters intracellular zinc by utilizing multiple cellular zinc importers and exporters as a means of nutritional immunity. To overcome extreme zinc limitation within the host environment, pathogenic microbes have successfully evolved a number of mechanisms to secure sufficient concentrations of zinc for their survival and pathogenesis. In this review, we briefly discuss the zinc uptake systems and their regulation in the model fungus Saccharomyces cerevisiae and in major human pathogenic fungi such as Aspergillus fumigatus, Candida albicans, and Cryptococcus gattii.

• Journal of Nutrition and Health
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• 제51권6호
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• pp.489-497
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• 2018

본 연구에서는 고지방식이로 유도한 비만군과 저지방식이를 공급한 대조군에서 각 조직의 아연 농도와 아연수송체 발현 수준을 비교하여, 비만 상태가 아연 대사에 미치는 영향을 파악하고자 하였다. C57BL/6J mice를 두 군으로 나누어 각 군당 15마리씩 고지방식이 (비만군) 또는 저지방식이 (대조군)를 총 15주간 공급하였다. 본 연구 결과, 비만군은 대조군에 비해 체중 증가량, 부위별 지방조직, 혈청과 간의 중성지방과 콜레스테롤 농도, 혈청 ALT 및 AST 활성 등이 모두 유의적으로 높게 나타났다. 또한 혈청 렙틴과 염증성 사이토카인인 IL-6의 농도도 비만군에서 유의적으로 증가하였다. 조직 별 아연 농도를 비교한 결과, 간, 소장, 신장, 췌장 등의 측정한 모든 조직에서 비만군이 대조군에 비해 유의적으로 낮게 나타났으며, 대변으로 배설되는 아연 함량은 비만군이 대조군에 비해 유의적으로 높았다. 혈청 아연 농도의 경우 두 군 간 유의적인 차이가 없었으나, 혈청 내 아연-의존 금속효소인 ALP 활성은 비만군에서 대조군에 비해 유의적으로 낮게 나타나 아연의 기능적인 결핍을 확인하였다. 내인성 아연의 체외 배출에 관여하는 췌장 조직에서의 ZnT1 mRNA 수준은 비만군에서 대조군에 비해 유의적으로 높게 나타났으며, 식이 아연 흡수에 관여하는 소장에서의 Zip4와 ZnT1의 mRNA 수준은 두 군간에 유의적인 차이가 없었다. 간 조직의 경우, ZnT1과 Zip10 mRNA이 모두 비만군에서 유의적으로 증가하였다. 이상의 결과를 요약하면, 비만 상태는 아연의 배설 증가와 조직 내 아연 농도 감소를 유발하는 것으로 나타났으며, 이들 아연 대사의 변화는 췌장과 간 조직의 아연 수송체 발현 수준 변화와 밀접한 관련이 있는 것으로 보인다. 비만인들에서 아연 영양상태가 결핍되지 않도록 관심을 가져야 할 것으로 생각되며, 비만으로 인한 아연 대사의 이상 (dysfunction)을 억제하기 위해서는 아연 수송체 발현을 조절할 수 있는 요인들에 대한 이해가 더욱 필요할 것으로 생각된다.

• 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.