• 제목, 요약, 키워드: Mn-SOD

검색결과 196건 처리시간 0.043초

Molecular Cloning and Expression of Sequence Variants of Manganese Superoxide Dismutase Genes from Wheat

  • Baek, Kwang-Hyun;Skinner, Daniel Z.
    • 한국환경농학회지
    • /
    • v.29 no.1
    • /
    • pp.77-85
    • /
    • 2010
  • Reactive oxygen species (ROS) are very harmful to living organisms due to the potential oxidation of membrane lipids, DNA, proteins, and carbohydrates. transformed E.coli strain QC 871, superoxide dismutase (SOD) double-mutant, with three sequence variant MnSOD1, MnSOD2, and MnSOD3 manganese superoxide dismutase (MnSOD) gene isolated from wheat. Although all QC 871 transformants grown at $37^{\circ}C$ expressed mRNA of MnSOD variants, only MnSOD2 transformant had functional SOD activity. MnSOD3 expressed active protein when grown at $22^{\circ}C$, however, MnSOD1 did not express functional protein at any growing and induction conditions. The sequence comparison of the wheat MnSOD variants revealed that the only amino acid difference between the sequence MnSOD2 and sequences MnSOD1 and 3 is phenylalanine/serine at position 58 amino acid. We made MnSOD2S58F gene, which was made by altering the phenylalaine to serine at position 58 in MnSOD2. The expressed MnSOD2S58F protein had functional SOD activity, even at higher levels than the original MnSOD2 at all observed temperatures. These data suggest that amino acid variation can result in highly active forms of MnSOD and the MnSOD2S58F gene can be an ideal target used for transforming crops to increase tolerance to environmental stresses.

Modulation of MnSOD in Cancer: Epidemiological and Experimental Evidences

  • Kim, Ae-Kyong
    • Toxicological Research
    • /
    • v.26 no.2
    • /
    • pp.83-93
    • /
    • 2010
  • Since it was first observed in late 1970s that human cancers often had decreased manganese superoxide dismutase (MnSOD) protein expression and activity, extensive studies have been conducted to verify the association between MnSOD and cancer. Significance of MnSOD as a primary mitochondrial antioxidant enzyme is unquestionable; results from in vitro, in vivo and epidemiological studies are in harmony. On the contrary, studies regarding roles of MnSOD in cancer often report conflicting results. Although putative mechanisms have been proposed to explain how MnSOD regulates cellular proliferation, these mechanisms are not capitulated in epidemiological studies. This review discusses most recent epidemiological and experimental studies that examined the association between MnSOD and cancer, and describes emerging hypotheses of MnSOD as a mitochondrial redox regulatory enzyme and of how altered mitochondrial redox may affect physiology of normal as well as cancer cells.

폐포대식세포에서 내독소 자극에 의한 Superoxide Dismutase 유전자발현의 조절 기전 (Superoxide Dismutase Gene Expression Induced by Lipopolysaccharide in Alveolar Macrophage of Rat)

  • 박계영;유철규;김영환;한성구;심영수;현인규
    • Tuberculosis and Respiratory Diseases
    • /
    • v.42 no.4
    • /
    • pp.522-534
    • /
    • 1995
  • 연구배경: 내독소에 의한 급성 폐손상의 발병기전에서 산소기가 중요한 역할을 한다는 사실은 잘 알려져 있다. 세포내에는 이러한 산소기에 의한 세포의 손상을 방지하는 정상 방어기전으로 여러 항산화효소가 존재하는데, 이중 SOD는 세포대사과정이나 외부 자극에 의해 생성된 superoxide로부터 세포의 손상을 방지하는 역할을 한다. 세포내 SOD는 주로 이중체의 구조로 세포질에 존재하는 CuZnSOD와 사중체의 구조로 미토콘드리아에 존재하는 MnSOD의 두 종류가 알려져 있으나, 폐포대식세포에서의 SOD mRNA 발현 및 그 조절기전에 대해서는 확실히 규명되어 있지 않다. 본 연구의 목적은 백서의 폐포대식세포에서 내독소 자극에 의한 MnSOD와 CuZnSOD mRNA 발현양상을 관찰하고 내독소 자극시 니타나는 SOD mRNA 발현의 조절기전을 규명하는데 있다. 방법: 백서의 기관지폐포세척액에서 얻은 세포를 plastic plate에 부착시켜 폐포대식세포를 분리한 후 내독소를 자극하여 내독소 용량($0.01{\mu}g/ml{\sim}10{\mu}g/ml$)과 자극시간(0, 2, 4, 8, 24 hrs)에 따른 MnSOD와 CuZnSOD MnSOD 발현양상을 Northern blot analysis를 시행하여 관찰하였다. 다음 단계로 MsSOD와 CuZnSOD mRNA 발현의 조절기전을 밝히고자 폐포대식세포를 각각 AD($5{\mu}g/ml$) 또는 CHX($5{\mu}g/ml$)로 전처치한 후 내독소로 자극하여 MnSOD와 CuZnSOD mRNA의 발현양상을 관찰하였다. 한편 내독소 투여가 SOD mRNA의 안정성을 변화시키는지 여부를 평가하기 위해 폐포대식세포를 대조군과 투여군으로 나누어 SOD mRNA의 분해속도를 비교하였다. 총 세포내 RNA는 guanidinium thiocyanate/phenol/chloroform법을 이용하여 추출하였고, Northern blot analysis는 $^{32}P$로 표지된 백서의 MnSOD와 CuZnSOD cDNAs를 이용하여 시행하였다. 결과: 백서의 폐포대식세포에서 MnSOD mRNA의 발현은 내독소 투여량의 증가세 따라 증가되었고 내독소를 투여하고 8시간후에 정점을 이루었으나, CuZnSOD mRNA의 발현은 내독소의 용량 및 투여후 반응시간에 따라 변화하지 않았다. 내독소 투여후 MnSOD mRNA의 발현증가는 AD 또는 CHX 각각의 전처치에 의해 모두 억제되었다. MnSOD mRNA의 안정성은 내독소 투여에 의해 변화하지 않았다. 결론: 이상의 결과로 백서의 폐포대식세포는 내독소 자극에 반응하여 SOD를 생성하는 중요세포이고, 내독소에 의한 MnSOD mRNA의 발현은 전사단계에서 조정되며 mRNA의 안정성을 변화시키지 않고 새로운 단백의 합성이 필요한 것으로 사료된다.

  • PDF

Isoform-Specific Responses of Superoxide Dismutase to Oxidative Stresses and Hormones in Parquat-Tolerant Rehmannia glutinosa

  • Jamal, Arshad;Yoo, Nam-Hee;Yun, Song-Joong
    • Journal of Crop Science and Biotechnology
    • /
    • v.10 no.1
    • /
    • pp.8-12
    • /
    • 2007
  • All accessions of Rehmannia glutinosa show the unique characteristic of intrinsic tolerance to paraquat. The higher level of endogenous superoxide dismutase(SOD) activity and its increase upon paraquat treatment indicated the involvement of SOD in the tolerance mechanism to paraquat in R. glutinosa. In this study, we examined the isoform-specific response of SOD to oxidative stresses and hormones. Six SOD isoforms were found in the leaf, and they were identified as two MnSODs(named MnSOD I and MnSOD II, in order of increasing mobility), one FeSOD and three Cu/ZnSODs(named Cu/ZnSOD I, Cu/ZnSOD II, and Cu/ZnSOD III, in order of increasing mobility). MnSOD I, MnSOD II, FeSOD, Cu/ZnSOD I, Cu/ZnSOD II, and Cu/ZnSOD III, contributed to 4, 11, 7, 15, 30, and 32% of the total SOD activity, respectively. Total SOD activity levels in the leaf were increased by 4, 24, and 21% by paraquat, salicylic acid(SA), and yeast extract(YE), respectively, but little by ethephon. Six SOD isoforms responded differentially to these stresses and hormones. The activities of all the isoforms were increased by YE and SA except that of MnSOD I which was decreased by SA. The activities of MnSOD I, FeSOD, and CuZnSOD I were increased by paraquat. These results suggest that amelioration of oxidative stresses by SOD is fine-tuned by the differential expression of isoforms in R. glutinosa.

  • PDF

Bidirectional Regulation of Manganese Superoxide Dismutase (MnSOD) on the Radiosensitivity of Esophageal Cancer Cells

  • Sun, Guo-Gui;Hu, Wan-Ning;Wang, Ya-Di;Yang, Cong-Rong;Lu, Yi-Fang
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.13 no.7
    • /
    • pp.3015-3023
    • /
    • 2012
  • The mitochondrial antioxidant protein manganese superoxide dismutase (MnSOD) may represent a new type of tumor suppressor protein. Overexpression of the cDNA of this gene by plasmid or recombinant lentiviral transfection in various types of cancer leads to growth suppression both in vitro and in vivo. We previously determined that changes in MnSOD expression had bidirectional effects on adriamycin (ADR) when combined with nitric oxide (NO). Radiation induces free radicals in a manner similar to ADR, so we speculated that MnSOD combined with NO would also have a bidirectional effect on cellular radiosensitivity. To examine this hypothesis, TE-1 human esophageal squamous carcinoma cells were stably transfected using lipofectamine with a pLenti6-DEST plasmid containing human MnSOD cDNA at moderate to high overexpression levels or with no MnSOD insert. Blastidicin-resistant colonies were isolated, grown, and maintained in culture. We found that moderate overexpression of MnSOD decreased growth rates, plating efficiency, and increased apoptosis. However, high overexpression increased growth rates, plating efficiency, and decreased apoptosis. When combined with NO, moderate overexpression of MnSOD increased the radiosensitivity of esophageal cancer cells, whereas high MnSOD overexpression had the opposite effect. This finding suggests a potential new method to kill certain radioresistant tumors and to provide radioresistance to normal cells.

Soluble Expression of a Human MnSOD and Hirudin Fusion Protein in Escherichia coli, and Its Effects on Metastasis and Invasion of 95-D Cells

  • Yi, Shanze;Niu, Dewei;Bai, Fang;Li, Shuaiguang;Huang, Luyuan;He, Wenyan;Prasad, Anand;Czachor, Alexander;Tan, Lee Charles;Kolliputi, Narasaiah;Wang, Feng
    • Journal of Microbiology and Biotechnology
    • /
    • v.26 no.11
    • /
    • pp.1881-1890
    • /
    • 2016
  • Manganese superoxide dismutase (MnSOD) is a vital enzyme that protects cells from free radicals through eliminating superoxide radicals ($O^{2-}$). Hirudin, a kind of small active peptide molecule, is one of the strongest anticoagulants that can effectively cure thrombus diseases. In this study, we fused Hirudin to the C terminus of human MnSOD with the GGGGS linker to generate a novel dual-feature fusion protein, denoted as hMnSOD-Hirudin. The hMnSOD-Hirudin gene fragment was cloned into the pET15b (SmaI, CIAP) vector, forming a recombinant pET15b-hMnSOD-Hirudin plasmid, and then was transferred into Escherichia coli strain Rosetta-gami for expression. SDS-PAGE was used to detect the fusion protein, which was expected to be about 30 kDa upon IPTG induction. Furthermore, the hMnSOD-Hirudin protein was heavily detected as a soluble form in the supernatant. The purification rate observed after Ni NTA affinity chromatography was above 95%. The hMnSOD-Hirudin protein yield reached 67.25 mg per liter of bacterial culture. The identity of the purified protein was confirmed by western blotting. The hMnSOD-Hirudin protein activity assay evinced that the antioxidation activity of the hMnSOD-Hirudin protein obtained was $2,444.0{\pm}96.0U/mg$, and the anticoagulant activity of the hMnSOD-Hirudin protein was $599.0{\pm}35.0ATU/mg$. In addition, in vitro bioactivity assay showed that the hMnSOD-Hirudin protein had no or little cytotoxicity in H9c2, HK-2, and H9 (human $CD_4{^+}$, T cell) cell lines. Transwell migration assay and invasion assay showed that the hMnSOD-Hirudin protein could suppress human lung cancer 95-D cell metastasis and invasion in vitro.

식물의 냉해에 대한 생체방어기구로서 항산소성 효소의 유도 : (II) $Mn^{+2}$이온에 의한 세포내 SOD의 활성화와 벼 유묘의 내냉성 향상 (Induction of antioxygenic enzymes as defense systems in plant cells against low temperature stress : (II) $Mn^{+2}-induced$ SOD activation and enhancement of cold tolerance in rice seedlings)

  • 한창균;김종평;정진
    • Applied Biological Chemistry
    • /
    • v.34 no.2
    • /
    • pp.168-173
    • /
    • 1991
  • 벼 유묘에 의 한 $Mn^{+2}$(Mn-SOD의 cofactor)의 흡수는 유묘조직중 SOD 활성을 증가시킴과 아울러 유묘의 냉해저항성을 현저히 향상시키는 결과를 보였으며, SOD 활성 증가정도와 냉해 저 항성 향상정도간에는 정의 상관관계가 있었다. 이에 반하여, Fe-SOD와 Cu/Zn-SOD의 cofactor들인 $Fe^{+3},\;Cu^{+2},$$Zn^{+2}$의 흡수는 조직내 SOD활성이나 식물의 냉해저항성에 어떤 유의성 있는 영향도 미치지 않았다. 이러한 결과들이 시사하는 바는 아마도 superoxide에 의해 유도되고 $Mn^{+2}$의 존재에 의해 활성화된 Mn-SOD가 (최소한 벼의 경우에는) 저온 스트레스에 대항하는 생체방어 시스템의 중요한 子성분일 것이라는 점이다. 어느정도의 냉해억제효과가 있다고 인정된 Abscisic acid의 처리도 벼 유묘조직의 SOD 활성을 증가시켰다. 이 관찰결과도 식물의 냉해 유발상황 하에서 세포내 SOD가 담당하는 중요한 생체방어 역할을 부각시키는 또 하나의 정보를 제공한 것이다.

  • PDF

Manganese Superoxide Dismutase (MnSOD Val-9Ala) Gene Polymorphism and Susceptibility to Gastric Cancer

  • Moradi, Mohammad-Taher;Yari, Kheirollah;Rahimi, Zohreh;Kazemi, Elham;Shahbazi, Mehrdad
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.16 no.2
    • /
    • pp.485-488
    • /
    • 2015
  • Background: Oxidative stress caused by the generation of reactive oxygen species plays an important role in human carcinogenesis. Manganese superoxide dismutase (MnSOD) Val-9Ala in the mitochondrial target sequence is the best known polymorphism of this enzyme. The purpose of the current research was to assess the association of MnSOD Val-9Ala genotypes with the risk of gastric cancer. Materials and Methods: This case-control study covered 54 gastric cancer patients compared to 100 cancer free subjects as controls. Extraction of DNA was performed on bioptic samples and genotypes were identified with a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Results: The frequencies of MnSOD Ala/Ala, Ala/Val and Val/Val genotypes in healthy individuals were 24.3, 66.7 and 9%, respectively. However, in gastric cancer patients, Ala/Ala, Ala/Val and Val/Val were observed in 24.0, 48.0 and 28.0% (p=0.01). In patients the frequency of MnSOD Val allele was higher (52%) compared to that in controls (42%). Conclusions: The results of this study show a positive association between MnSOD Val-9Ala gene polymorphism and risk of gastric cancer disease in Iranian population.

miR-23a Regulates Cardiomyocyte Apoptosis by Targeting Manganese Superoxide Dismutase

  • Long, Bo;Gan, Tian-Yi;Zhang, Rong-Cheng;Zhang, Yu-Hui
    • Molecules and Cells
    • /
    • v.40 no.8
    • /
    • pp.542-549
    • /
    • 2017
  • Cardiomyocyte apoptosis is initiated by various cellular insults and accumulated cardiomyocyte apoptosis leads to the pathogenesis of heart failure. Excessive reactive oxygen species (ROS) provoke apoptotic cascades. Manganese superoxide dismutase (MnSOD) is an important antioxidant enzyme that converts cellular ROS into harmless products. In this study, we demonstrate that MnSOD is down-regulated upon hydrogen peroxide treatment or ischemia/reperfusion (I/R) injury. Enhanced expression of MnSOD attenuates cardiomyocyte apoptosis and myocardial infarction induced by I/R injury. Further, we show that miR-23a directly regulates the expression of MnSOD. miR-23a regulates cardiomyocyte apoptosis by suppressing the expression of MnSOD. Our study reveals a novel model regulating cardiomyocyte apoptosis which is composed of miR-23a and MnSOD. Our study provides a new method to tackling apoptosis related cardiac diseases.

The Virulence of Vibrio vulnificus is Affected by the Cellular Level of Superoxide Dismutase Activity

  • Kang, In-Hye;Kim, Ju-Sim;Lee, Jeong-K.
    • Journal of Microbiology and Biotechnology
    • /
    • v.17 no.8
    • /
    • pp.1399-1402
    • /
    • 2007
  • The virulence of superoxide dismutase (SOD) mutants of Vibrio vulnificus, as tested by intraperitoneal injection into mice, decreases in the order of sodC mutant, sodA mutant, and sodB mutant lacking CuZnSOD, MnSOD, and FeSOD, respectively. The survival of SOD mutants under superoxide stress also decreases in the same order. The virulence of soxR mutant, which is unable to induce MnSOD in response to superoxide, is similar to that of the sodA mutant, as the survival of the soxR mutant under superoxide stress is similar to that of the sodA mutant. Consistently, the lowered survival of the soxR mutant is complemented not only with soxR but also with sodA. Thus, the virulence of V. vulnificus is significantly affected by the cellular level of SOD activity, and an increase in SOD level through MnSOD induction by SoxR under superoxide stress is essential for virulence.