• 대한핵의학회지
• /
• 제33권1호
• /
• pp.1-10
• /
• 1999

Cancer cells are known to show increased rates of glycolysis metabolism. Based on this, PET studies using F-18-fluorodeoxyglucose have been used for the detection of primary and metastatic tumors. To account for this increased glucose uptake, a variety of mechanisms has been proposed. Glucose influx across the cell membrane is mediated by a family of structurally related proteins known as glucose transporters (Gluts). Among 6 isoforms of Gluts, Glut-1 and/or Glut-3 have been reported to show increased expression in various tumors. Increased level of Glut mRNA transcription is supposed to be the basic mechanism of Glut overexpression at the protein level. Some oncogens such as src or ras intensely stimulate Glut-1 by means of increased Glut-1 mRNA levels. Hexokinase activity is another important factor in glucose uptake in cancer cells. Especially hexokinase type II is considered to be involved in glycolysis of cancer cells. Much of the hexokinase of tumor cells is bound to outer membrane of mitochondria by the porin, a hexokinase receptor. Through this interaction, hexokinase may gain preferred access to ATP synthesized via oxidative phosphorylation in the inner mitochondria compartment. Other biologic factors such as tumor blood flow, blood volume, hypoxia, and infiltrating cells in tumor tissue are involved. Relative hypoxia may activate the anaerobic glycotytic pathway. Surrounding macrophages and newly formed granulation tissue in tumor showed greater glucose uptake than did viable cancer cells. To expand the application of FDG PET in oncology, it is important for nuclear medicine physicians to understand the related mechanisms of glucose uptake in cancer tissue.

• 한국식품영양학회지
• /
• 제10권1호
• /
• pp.37-43
• /
• 1997

본 연구는 지질의 과산화에 대한 항산화 효과를 조사하기 위하여 엉겅퀴(Silybum marianum)로부터 silymarin 및 silybin을 정제하여 실험하였다. Silymarin 및 silybin은 xanthine oxidase system에서 superoxide anion의 생성을 억제하였다. 쥐의 간 mitochondria에서는 silymarin 및 silybin은 reduced nicotinamide adenine dinucleotide phosphate(NADPH)에 의해 효과적 또는 ascorbic acid 또는 Fenton's reagent에 의하여 비효소적으로 유도되는 지질의 과산화를 억제하였다. 또 mitochondria의 지질과산화도 silymarin 및 silybin에 의하여 억제되었고 NADPH 의존 cychrome P-450 reductase에 의한 Fe2+의 산화도 silymarin 및 silybin에 의하여 억제되었다. Silymarin 및 silybin은 microsome의 효소 시스템 및 linoleic acid hydroperoxide induced peroxidation system에서 지질의 과산화의 연쇄반응에서 유리기의 억제효과가 있었다.

• 한국동물생명공학회지
• /
• 제35권1호
• /
• pp.102-111
• /
• 2020

Nitric oxide (NO)-induced protein S-nitrosylation triggers mitochondrial dysfunction and was related to cell senescence. However, the exact mechanism of these damages is not clear. In the present study, to investigate the relationship between in vitro aging and NO-induced protein S-nitrosylation, oocytes were treated with sodium nitroprusside dihydrate (SNP), and the resultant S-nitrosylated proteins were detected through biotin-switch assay. The results showed that levels of protein S-nitroso thiols (SNO)s and expression of S-nitrosoglutathione reductase (GSNOR) increased, while activity and function of mitochondria were impaired during oocyte aging. Addition of SNP, a NO donor, to the oocyte culture led to accelerated oocyte aging, increased mitochondrial dysfunction and damage, apoptosis, ATP deficiency, and enhanced ROS production. These results suggested that the increased NO signal during oocyte aging in vitro, accelerated oocyte degradation due to increased protein S-nitrosylation, and ROS-related redox signaling.

• Applied Microscopy
• /
• 제29권4호
• /
• pp.459-470
• /
• 1999

9, 10일 계배의 대뇌 신경세포 분화의 변화를 관찰하기 위하여 신경세포의 미세구조 변화를 전자현미경을 이용하여 관찰하였으며, 또한 대뇌 단백질, 탈수소효소의 활성도 및 ATP의 변화상을 분석한 결과는 다음과 같다. 대뇌 신경세포의 미세구조의 변화는 발생 9일 계배의 염색질은 핵질내에 비교적 고르게 분포해 있었으며 핵막은 2중막으로 아주 선명하게 구별되어 있음을 관찰할 수 있었다. 특히 조면소포체와 Golgi복합체가 잘 발달되어 있었으며, 또한 polysome이 관찰되었고 synaptic소포들이 산재되어 있었다. 10일 배양군의 계배의 신경세포는 염색질이 고루 분포해 있었으며 핵막을 뚜렷이 구분할 수 있었다. 세포질을 포함한 조면소포체와 mitochondria 그리고 Golgi 복합체가 비교적 잘 발달되어 있었다. 계배대뇌의 9일 배양군에서는 37개의 polypeptide band들이 분리되었고, 10일 배양군에서는 38개의 band가 생성되었다. 탈수소효소 활성도는 배양시간이 증가할 수록 증가하는 현상을 보였는데, LDH의 활성도는 9일 배양시 11.07이며 10일 배양시에는 12.12이였고, MDH는 각각 11.89와 13.44로 나타났다. 그리고 SDH는 9일 배양군에서는 8.45이며 10일 배양군에서는 10.52의 활성을 보여 증가했음을 알 수 있다. ATP의 변화는 10일 배양군$(2.10\times10^{-4}mol/ml)$이 9일 배양군$(2.50\times10^{-6}mol/ml)$에 비해 감소현상을 보였다.

• Applied Microscopy
• /
• 제28권4호
• /
• pp.563-575
• /
• 1998

To investigate the changes during the differentiation of the cerebral neurons of chick embryo of tne embryogenic day (ED) 7 and 8, the ultrastructural changes in the cerebral neurons, the activity of dehydronases (LDH, MDH and SDH), protein expression profile and adenosine triphosphate concentration were analyzed. In ED 7 chick embryos, relatively large nucleus, centrally located nucleolus, evenly spread chromatin over nucleoplasm, and prominent nuclear envelope were observed. Oval-shaped mitochondria with well-developed cristae were present over entire cytoplasm. In ED 8 chick embryos, evenly spread chromatin over nucleoplasm, and prominent nuclear envelope were observed. In the cytoplasm, well-developed rough endoplasmic reticulum and Golgi complex were observed. In ED 7 chick embryos and ED 8 chick embryos, 31 polypeptide bands and 34 polypeptide bands were observed, respectively. The activities of dehydrogenases were lower in ED 7 chick embryos than in ED 8 chick embryos. LDH activity was 8.16 (ED 7) and 9.28 (ED 8), MDH activity was 7.98 (ED 7) and 10.10 (ED 8), and SDH activity was 5.49 (ED 7) and 7.14 (ED 8) respectively. The ATP concentration remained unchanged over ED 7 and 8.

• Archives of Plastic Surgery
• /
• 제42권2호
• /
• pp.143-149
• /
• 2015

Background Adipose tissue damage of cryopreserved fat after autologous fat transfer is inevitable in several processes of re-transplantation. This study aims to compare and analyze the survivability of adipocytes after thawing fat cryopreserved at $-20^{\circ}C$ by using thawing methods used in clinics. Methods The survival rates of adipocytes in the following thawing groups were measured: natural thawing at $25^{\circ}C$ for 15 minutes; natural thawing at $25^{\circ}C$ for 5 minutes, followed by rapid thawing at $37^{\circ}C$ in a water bath for 5 minutes; and rapid thawing at $37^{\circ}C$ for 10 minutes in a water bath. The survival rates of adipocytes were assessed by measuring the volume of the fat layer in the top layers separated after centrifugation, counting the number of live adipocytes after staining with trypan blue, and measuring the activity of mitochondria in the adipocytes. Results In the group with rapid thawing for 10 minutes in a water bath, it was observed that the cell count of live adipocytes and the activity of the adipocyte mitochondria were significantly higher than in the other two groups (P<0.05). The volume of the fat layer separated by centrifugation was also measured to be higher, which was, however, not statistically significant. Conclusions It was shown that the survival rate of adipocytes was higher when the frozen fat tissue was thawed rapidly at $37^{\circ}C$. It can thus be concluded that if fats thawed with this method are re-transplanted, the survival rate of cryopreserved fats in transplantation will be improved, and thus, the effect of autologous fat transfer will increase.

• BMB Reports
• /
• 제28권3호
• /
• pp.254-260
• /
• 1995

Cytochrome oxidase was purified from bovine-heart mitochondria and its enzymatic properties were examined. The purified cytochrome oxidase was identified by its absorption spectrum and chromatogram through gel filtration. The specific activity, purification degree and yield of purified cytochrome oxidase were 18 nmol/mg/ml/min, 24.83 fold and 0.93%, respectively. The activity of the enzyme assayed by a ferrocytochrome $c-O_2$ system was optimized at $25^{\circ}C$ and pH 6.5. Examining the effect of nonionic detergents established that cytochrome oxidase was deactivated by Triton X-100. The oxidase was activated by Tween 80 and deactivated by Tween 20. The Michaelis constant and maximum velocity of the oxidase for ferrocytochrome c were 0.032~0.044 mM and 0.019~0.021 mM/min, respectively. After adaption to basal diet for a week, experimental diets containing 6 mg Cu/kg, or zero mg Cu/kg, or 12 mg Cu/kg were fed to a control group, a copper-free group and a copper-rich group of Sprague-Dawley rats, respectively, for 4 weeks. The specific activities assayed for the ferrocytochrome $c-O_2$ system of isolated cytochrome oxidase from the rat liver of control, copper-free, and copper-rich group were 1.00, 1.19, and 0.878 nmol/mg/ml/min, respectively. Their degrees of purification were 11.38, 10.82 and 8.78 fold, respectively. The specific activities for liver and heart mitochondrial cytochrome oxidase of copper-free/copper-rich groups assayed using the ferrocytochrome $c-O_2$ system were 81.4% and 96.4%/64.1% and 61.1%, respectively, compared with those of the control.

• Journal of Nutrition and Health
• /
• 제44권4호
• /
• pp.284-291
• /
• 2011

The purpose of the present study was to examine the effects of water extracts from red pepper seeds powder on antioxidative enzyme activities and oxidative damage in groups of rrats fed high-fat and high-cholesterol diets group (HFC). The Rrats were divided into the following five experimental groups which are : composed of a normal diet group, a high fat high cholesterol diet group, and a high fat high cholesterol diet group supplemented with different amounts contents (1%, 2% and 4%) of red pepper seeds powder water extracts supplemented groups (HFCW1, HFCW2 and HFCW4, respectively). Body weight gains and food intake were lower ofin the red pepper seed water extracts groups were lower than those inof the HFC group. Hepartic xanthine oxidase (XOD) activity was decreased in the HFCW2 and HFCW4 groups compared to the HFC group. Hepartic glutathione peroxidase (GSH-px) activitiyactivity was increased in the HFCW4 group compared to the HFC group. Hepatic superoxide radicals within the mitochondria and microsomes of cells were significantly reduced in the HFCW2 and HFCW4 groups compared to the HFC group. Hepartic hydrogen peroxide in the cytosol was significantly reduced in the HFCW3 and HFCW4 groups compared to the HFC group. Hepatic carbonyl values in the microsomes and mitochondria were significantly reduced in the HFCW4 group compared to the HFC group. Hepartic thiobarbituric acid reaction substance (TBARS) activity was decreased in the HFCW2 group compared to the HFC group. These results suggest that water extracts of red pepper seeds powder may reduce oxidative damage by activation of antioxidative defense systems in rats fed high fat-high cholesterol diets.

• Asian-Australasian Journal of Animal Sciences
• /
• 제33권11호
• /
• pp.1763-1769
• /
• 2020

Objective: This study was conducted to investigate the effect of L-carnitine on the pig semen characteristics during storage. Methods: Spermatozoa samples were examined for spermatozoa quality and then randomly divided into 5 groups: 0 (control), 12.5, 25, 50, and 100 mM L-carnitine. Sperm motility, plasma membrane integrity and antioxidant parameters (total reactive oxygen species, total antioxidant capacity, and malondialdehyde) were evaluated after 0, 3, 5, and 10 day cooled-storage at 17℃. Moreover, ATP content, mitochondria activity as well as sperm-binding and in vitro fertilizing ability of preserved boar sperm were also investigated. Results: Supplementation with 50 mM L-carnitine could effectively maintain boar sperm quality parameters such as sperm motility and membrane integrity. Besides, we found that L-carnitine had positive effects on boar sperm quality mainly through improving antioxidant capacities and enhancing ATP content and mitochondria activity. Interestingly, by assessing the effect of L-carnitine on sperm fertility and developmental potential, we discovered that the extender containing L-carnitine could improve sperm quality and increase the number of sperms bounding to zona pellucida, without improving in vitro fertility and development potential. Conclusion: These findings suggested that the proper addition of L-carnitine to the semen extender improved boar sperm quality during liquid storage at 17℃.

• Molecules and Cells
• /
• 제39권2호
• /
• pp.119-128
• /
• 2016

Angelica polymorpha Maxim root extract (APRE) is a popular herbal medicine used for treating stomachache, abdominal pain, stomach ulcers, and rheumatism; however the effect of APRE on cancer cells has not yet been explored. Here, we examined APRE cytotoxicity seen on target neuroblastoma cells (NB) using cell viability assays, DAPI visualization of fragmented DNA, and Western blotting analysis of candidate signaling pathways involved in proliferation and apoptosis. We demonstrated that APRE reduced cell viability in NB to a greater extent than in fibroblast cells. In addition, we found that APRE could inhibit the three classes of MAPK proteins and could also down-regulate the PI3K/AKT/GSK-$3{\beta}$ activity all being relevant for proliferation and survival. APRE could also up-regulate Bax expression and down-regulate Bcl-2 and Mcl-1. With APRE treatment, depolarization of mitochondria membrane potential and activation of caspase-3 was demonstrated in the SH-SY5Y cells. We could not found increased activity of death receptor and caspase-8 as markers of the extrinsic apoptosis pathway for the APRE treated cells. In presence of a caspase-3 siRNA and a pan-caspase inhibitor, APRE could not reduce the viability of NB cells to a significant degree. So we predicted that with APRE, the intrinsic pathway was solely responsible for inducing apoptosis as we also showed that the non-caspase autophagy pathway or ER stress-ROS mediated pathways were not involved. These findings demonstrate that an intrinsic mitochondria-mediated apoptosis pathway mediates the apoptotic effects of APRE on SH-SY5Y cells, and that APRE shows promise as a novel agent for neuroblastoma therapy.