• Title/Summary/Keyword: mitochondria

Search Result 1,652, Processing Time 0.039 seconds

Studies on the Fine Structures of Mouse Oocyte Whose Maturation has been suppressed in Vitro by Dibutyryl Cyclic AMP (Dibutyryl Cyclic AMP에 의해 成熟이 抑制된 Mouse 卵子의 微細構造에 관한 硏究)

  • 崔林淳
    • The Korean Journal of Zoology
    • /
    • v.18 no.2
    • /
    • pp.87-101
    • /
    • 1975
  • Electron microscopic studies on the ultrastructure of the mouse oocyte were made to investigate the inhibition of germinal vesicle breakdown by dibutyryl cAMP. The nuclear membrane of the dibutyryl cAMP-treated oocyte is characterized by a decreased degree of folding, maintains the normal double membrane structure, and shows an increased occurrence of the nuclear pore. It is suggested that these may be related to the suppression of the maturation of oocytes at the germinal vesicle. Mitochondria in the control cell were shown to be spread evenly throughout the cytoplasm and structurally underdeveloped or transitionary having little cristae development. On the contrary, mitochondria in the treated oocyte were found to be localized mainly around the nucleus and to show a greater extent of cristae development. The oocyte treated with dibutyryl cAMP appears to have fewer and structurally simpler lysosomes as compared to the control. The Golgi complex in the control oocyte exhibits the typical granular and lamellar structure, whereas that in the treated cell is poorly developed. Many multivesicular bodies, tonofilaments, and free ribosomes were observed in the control as well as in treated cells. The microvilli become structurally irregular, and a development of the perivitelline space is apparent in the treated oocyte. It is concluded that there is no basic difference in the ultrastructure between the oocytes treated with dibutyryl cAMP for 24 hours in the medium and those collected directly from the follicle. However, the finding that dibutyryl cAMP induces a development of more pores along the nuclear membrane strongly suggests the possibility that this compound inhibits the maturation of oocytes by influencing the permeability of the nuclear membrane.

  • PDF

Blue Light Photosensitization in Mitochondrial Membrane of Plant Cells (식물세포 미토콘드리아막에서 일어나는 청색광 Photosensitization)

  • Kim, Kyung-Hyun;Kim, Jong-Pyung;Jung, Jin
    • Korean Journal of Environmental Agriculture
    • /
    • v.6 no.2
    • /
    • pp.94-100
    • /
    • 1987
  • Plant mitochondria, irradiated with blue-colored $sunlight(350{\sim}500nm)$ under aerobic and anaerobic conditions, were assayed as to the electron transfer activity of respiratory enzyme system, and compared with those irradiated with orange-colored light(white sunlight minus blue-colored light). The respiratory activity of mitochondria was most seriousely inhibited by illumination with blue-colored light under aerobic condition. Deaeration of mitochondrial suspension resulted in substantial decrease of the photoinhibition by blue-colored light. Meanwhile, orange-colored light demonstrated much less effectiveness-almost ineffectiveness-in causing the inhibition of mitochondrial respiration system. The results of enzymatic assay revealed a strong possibility that FMN in NDH and heme group at least in cytochrome c oxidase, but not FAD in SDH, are the photodynamic sensitizers in mitochondrial inner membrane. Also worthwhile to note is the significant difference from the others of SDH in its photoinhibitory response to the light quality of visible light; that the inhibition of SDH by irradiation was not affected by atmospheric condition and that orange-colored light gave rise to considerable extents of inhibition to the enzyme. This observation was tentatively interpreted in terms of photosensitized reaction not involving molecular oxygen possibly catalyzed by Fe-S centers in the enzyme. The superoxide production and the membrane peroxidation of mitochondria under various treatments also indicated that there was blue-light photodynamic reaction in mitochondria involving active oxygens.

  • PDF

Reduction of Mitochondrial Derived Superoxide by Mito-TEMPO Improves Porcine Oocyte Maturation In Vitro (Mito-TEMPO에 의한 미토콘드리아 유래 초과산화물의 감소가 돼지 난모세포 성숙에 미치는 영향)

  • Yang, Seul-Gi;Park, Hyo-Jin;Lee, Sang-Min;Kim, Jin-Woo;Kim, Min-Ji;Kim, In-Su;Jegal, Ho-Geun;Koo, Deog-Bon
    • Journal of Animal Reproduction and Biotechnology
    • /
    • v.34 no.1
    • /
    • pp.10-19
    • /
    • 2019
  • Morphology of cumulus-oocyte-complexes (COCs) at germinal vesicle (GV) stage as one of the evaluation criteria for oocyte maturation quality after in vitro maturation (IVM) plays important roles on the meiotic maturation, fertilization and early embryonic development in pigs. When cumulus cells of COCs are insufficient, which is induced the low oocyte maturation rate by the increasing of reactive oxygen species (ROS) in porcine oocyte during IVM. The ROS are known to generate including superoxide and hydrogen peroxide from electron transport system of mitochondria during oocyte maturation in pigs. To regulate the ROS production, the cumulus cells is secreted the various antioxidant enzymes during IVM of porcine oocyte. Our previous study showed that Mito-TEMPO, superoxide specific scavenger, improves the embryonic developmental competence and blastocyst formation rate by regulating of mitochondria functions in pigs. However, the effects of Mito-TEMPO as a superoxide scavenger to help the anti-oxidant functions from cumulus cells of COCs on meiotic maturation during porcine oocyte IVM has not been reported. Here, we categorized experimental groups into two groups (Grade 1: G1; high cumulus cells and Grade 2: G2; low cumulus cells) by using hemocytometer. The meiotic maturation rate from G2 was significantly (p < 0.05) decreased (G1: $79.9{\pm}3.8%$ vs G2: $57.5{\pm}4.6%$) compared to G1. To investigate the production of mitochondria derived superoxide, we used the mitochondrial superoxide dye, Mito-SOX. Red fluorescence of Mito-SOX detected superoxide was significantly (p < 0.05) increased in COCs of G2 compared with G1. And, we examined expression levels of genes associated with mitochondrial antioxidant such as SOD1, SOD2 and PRDX3 using a RT-PCR in porcine COCs at 44 h of IVM. The mRNA levels of three antioxidant enzymes expression in COCs from G2 were significantly (p < 0.05) lower than COCs of G1. In addition, we investigated the anti-oxidative effects of Mito-TEMPO on meiotic maturation of porcine oocyte from G1 and G2. Meiotic maturation and mRNA levels of antioxidant enzymes were significantly (p < 0.05) recovered in G2 by Mito-TEMPO ($0.1{\mu}M$, MT) treatment (G2: $68.4{\pm}3.2%$ vs G2 + MT: $73.9{\pm}1.4%$). Therefore, our results suggest that reduction of mitochondria derived superoxide by Mito-TEMPO may improves the meiotic maturation in IVM of porcine oocyte.

The Effects of Isocaloric High-Fat Diet and Endurance Exercise on Insulin Resistance and Mitochondria Biogenesis (Isocaloric high-fat diet와 지구성 운동이 인슐린 저항성과 미토콘드리아 생합성에 미치는 영향)

  • Jung, Su-Ryun;Kwon, Dae-Yong;Kim, Jin-Hwan;Kang, Ho-Youl
    • 한국체육학회지인문사회과학편
    • /
    • v.51 no.3
    • /
    • pp.353-362
    • /
    • 2012
  • The purpose of this research was to find effects of high fat diet and endurance exercise on mitochondria biosynthesis and insulin resistance in male Wister rat. Th rats were randomly separated into 4 groups: A, Isocaloric high fat diet group (50% of calories from fat), B. Chow group, C. Isocaloric high fat diet with endurance exercise (treadmill running, slop 8%, 23 m/min, 120 min/day, 5 days per week), D. Chow group with endurance exercise. Both Isocaloric high fat diet group and chow group were given an equal caloric composition with 3.2kcal/g. equal amount of food were checked every day and given to both groups. 4 weeks of high fat diet did not show any change in body weight and amount of body fat. Further the level of glucose and insulin in blood, and insulin-stimuilated glucose transport rate in epitrochlearis muscle was not affected by Isocaloric high fat diet. However, the endurance exercise showed statistically significant change in the level of insulin in blood. Although either Isocaloric high fat diet or endurance exercise alone did not change on mitochondria biogenesis marker, Isocaloric high fat diet with endurance exercise could induce the increased level of marker (p<0.05). Also, plasma free fatty acids were increased in this group. From this investigation, Isocaloric high fat diet with moderate-intensity endurance exercise is effective way to induce mitochondrial biogenesis.

Ultrastructure of the Hindgut Epithelial Cells in the Cockroach, Blattella germanica L. (바퀴의 後腸 上皮細胞들에 대한 微細構造)

  • Yu, Chai Hyeock
    • The Korean Journal of Zoology
    • /
    • v.28 no.1
    • /
    • pp.44-59
    • /
    • 1985
  • The epithelium of the hindgut in the german cockroach, Blattella germanica Linne, was observed with electron microscope. The epithelium of the ileum, which is located at the anterior hindgut, is composed of a single layer of squamous and cuboidal cells. The liminal surface of the epithelium is lined with the cuticular intima. The epithelial cells contain cell organelles expected to be found in absorptive cells, and some epithelial cells have numerous lamelated crystals, the "spherites". The rectal epithelium of posterior hindgut is composed of rectal pads which are covered with cuticular intima on the luminal side. The rectal pads are composed of columnar absorptive cells and basal cells. The apical plasma membrane of columnar cell is made of microvilli, where mitochondria associated with some of the microvilli. The lateral plasma membrane is highly infolded and space is an uniform width of approximately 200$\\AA$. Well developed mitochondria are found closely associated with the infoldings and this is referred to as the "mitochondrial-scalariform complex". A septate junction is found near the apical zone between the columnar absorptive cells, whereas many desmosomes and intercellular spaces are formed between the columnar cells. Basal cells are bowl-shaped where the convex surface is inlaid into the basal surface of the columnar cells while the concave surface faces the basal lamina. The cytoplasm of the basal cell is electron dense and contains well developed cell organelles. The basal sheath is located between the basal membrane and basal lamina, providing barrier between the epithelium and the hemolymph. The epithelium is surrounded by the subepithelial space and muscles. The subepithelial space, which is composed of fibrous connective tissue, is innervated by many tracheoles and axons.

  • PDF