Changes in cytoskeletal organization during myotube formation in vitro

Tez (Doktora) - University of East AngliaAnadolu Üniversitesi, Fen Bilimleri Enstitüsü, Biyoloji Anabilim DalıKayıt no: 19000The cytoskeletal changes accompanying CO25 myoblast differentia- tion, and transformation have been investigated using various techni- ques. A very significant change in microtubule organization was found to occur upon inducing differentiation by transferring the cells into a medium containing horse serum. Elongation of the cells was accompa- nied by a change in microtubule distribution such that all the micro- tubules ran parallel to the long axis of the cells and the radial organization from centrosomes was lost. The transient formation of primary cilia in the elongating cells was proceeded by an aggregation and fusion of all the centrioles wit- hin the cells. There seemed to be an apparent shift in microtubule nucleation centres from the centrosomes in myoblasts to a perinuclear distribution in myotubes. The capacity of these structures to nucleate microtubules was studied by allowing repolymerization after nocodazole treatment. The possible significance of these rather string changes in centriole organization, and in MTOC capacity, and the possible role of the primary cilia in myogenesis are discussed. During the course of the research the antibody MPM-13, supposed to be a centrosomal marker, was used. A very variable distribution of peri-centrosomally located granules was identified in myoblasts with MPM-13. Double immunostaining experiments demonstrated that MPM- 13 stained elements of the Golgi rather than a supposed centrosomal component. Study of the distribution of actin cables showed that stress fib- res were very rich in myoblasts, but decreased markedly in number as the myoblasts elongated. After fusion, an increase of F-actin cables occurred in newly formed myotubes, F-actin finally became highly or- ganised in a periodic distribution along the myofibrils in vitro. In transformed CO25 myoblasts, the distribution of F-actin was very variable. A few actin cables were seen in some cells which were attached to the substratum, but stress fibres were lacking in most cells, which were rounded cells in foci and not attached to the sub- stratum. A possible relationship of these changes to the focal con- tacts is considered

Kültür Fibroblast Hücrelerinde Mikrotubül Oluşum Merkezi

Many cell types express an internal and external polarization of various cytoplasmic components as microtubule organizing centre (MTOC). It is believed that MTOC and increasing and decreasing of cytoplasmic microtubules are very important for direction of cell movement and cell polarity. In our experiments, the relationship between MTOC and cytoplasmic microtubules is examined by using immunofluorescence methods on 3T3 fibroblast cell lines. Our results demonstrated that MTOC has a central location in most cells. Moreover a coordination between microtubule’s and centrioles during formation of cytoplasmic microtubules was identified. It has been shown that the microtubule formation initiated at the cell centre in which centrioles were located.Hücre türlerinin çoğu, mikrotubül oluşum merkezi (MTOC) gibi çeşitli sitoplazmik bileşenlerin iç ve dış biçimlenmelerinin etkisi altındadır. MTOC ve oluşan ya da yıkılan sitoplazmik mikrotubüller, hücre hareket yönü ve hücre biçimlenmesinde çok önemlidir. Çalışmamızda, 3T3 fibroblast kültür hücrelerinde immunofluoresans yöntemi kullanarak, sitoplazmik mikrotubüller ve MTOC arasıhdaki ilişki araştırıldı. Bulgularımız, hücrelerin büyük çoğunluğunda, MTOC'un, hücre merkezine yakın konumda olduğunu açık olarak göstermiştir. Bunun yanışım, sitoplazmik mikrotubüllerin oluşumu sırasında, sentrioller ile mikrotubüller arasında uyumlu bir ilişki olduğu görülmüştür. Çalışmamızda, mikrotubül oluşumunun sentriyollerin bulunduğu hücre merkezinde meydana geldiği ortaya konmuştur

Effects of carvacrol on a human non-small cell lung cancer (NSCLC) cell line, A549

15th Annual Meeting of the Japanese-Association-for-Animal-Cell-Technology -- NOV 11-15, 2002 -- Fuchu, JAPANWOS: 000222558600036Carvacrol, the predominant monoterpene in many essential oils of Labitae including Origanum, Satureja, Thymbra, Thymus, and Corydothymus has substantial antibacterial, anti fungal, antihelmintic, insecticial, analgesic and antioxidant activities. In this study a human non-small cell lung cancer (NSCLC) cell line, A549 was used. Approximately 75% of lung cancer is non-small cell carcinoma (NSCLC) which comprises several histologic types: squamous cell, adenocarcinoma and large cell carcinoma. It was reported that the proportion of lung tumors diagnosed as adenocarcinoma has increased. For this reason A549 cell line was chosen for this study. To investigate the effects of carvacrol on cell morphology, apoptosis and total protein amount, the cells were incubated with various concentration of carvacrol in DMSO for 24 hours. In carvacrol applied A549 cell line, increase in dose of carvacrol caused a decrease in cell number, degeneration of cell morphology and a decrease in total protein amount. To characterize carvacrol induced changes in cell morphology, cells were examined by light microscopy. Cells were treated with carvacrol were seen to have detached from the disk, with cell rounding, cytoplasmic blebbing and irregularity in shape. The data demonstrate that carvacrol is very potent inhibitor of cell growth in A549 cell line.Japanese Assoc Anim Cell Techno

Effects of Some Chemical Agents Which May Has Antimitotic Effects on Reticuloendothelial System (Res)

Günümüzde doğal ya da yapay bir çok kimyasal bileşiğin antimitotik etkisinin bilinmesine karşın, etki mekanizmaları hakkında oldukça az bilgiye rastlanılmaktadır. Antimitotik olduğu bilinen kimyasal bir bileşen model alınarak sentetik yolla elde edilmiş olan Bis tetrathiafulvalene türevlerinin, mitotik inhibitör etkili olabileceği düşünülmüştür. Bu yolla yapay olarak sentez edilen ve T3, T5 olarak kodlanmış maddelerin formül yapısından yola çıkılarak antimitotik olabileceği düşünülmüş ve çalışmamızın kimyasal deney materyalini oluşturmuştur. Yaşam boyu mitotik aktivite gösteren hücreler içeren retiküloendotelial sistem (RES)’ deki bazı dokular üzerine olası etkileri araştırılmıştır. Sentez edilen bu kimyasalların, in vivo olarak test edilmesine yönelik olan bu çalışmada kullanılan test materyallerinin olası etkilerini gösterebilmek amacıyla kan, kemik iliği ve dalak dokuları incelenmiş ve bu konuda bir test yöntemi de geliştirilmeye çalışılmıştır. Kimyasal maddelerin hedef dokular üzerindeki antimitotik etkileri, kontrol grupları ile deney grupları karşılaştırılarak değerlendirilmiştir. Yapılan çalışmanın sonucunda, test edilmiş olan kimyasal maddelerin antimitotik etkili olduğu söylenebilir.Nowadays, many natural or artificial chemicals are known as mitotic inhibitors but the information about their effect mechanisms is very little. Bis tetrathiafulvalene strains, which were synthesized by using an antimitotical chemical compound as a model, were thought to have mitotic inhibitor effects. Thus, chemicals with codenames T3 and T5, were synthesized with the way mentioned above and these chemicals became the main chemical materials of our research . Possible effects of these chemicals were investigated on some tissues of reticuloendothelial system (RES) which includes particular cells showing mitotic activitiy for the life. In this study, which was devoted to in vivo testing of the synthesized chemicals, to investigate the effects of test materials, blood, bone marrow and spleen tissues were examined and also a test method were tried to be developed about this subject. The antimitotic effects of the chemical materials on target tissues were evaluated comperatively both between test groups and between control groups. As a result of this study, it can be concluded that the tested chemical materials have antimitotic effects

Dill seed oil as a possible contraceptive agent: antiangiogenic effects on endothelial cells

Dill (Anethum graveolens L.) essential oil is wide spread in the food, beverage and pharmaceutical sectors. Dill is a member of the Apiaceae (Umbelliferae) family. It has the following biological activities: antioxidant, antifungal, antibacterial, antimicrobial, antihyperlipidemic, antihypercholesterolemic, antispasmodic, antiproliferative and anti-inflammatory. Aqueous extract of dill seed has reported effects on sex hormones and infertility potential. Moreover, boiled dill seed has an impact on reducing labor duration in giving birth. Implantation and placentation are necessary for a healthy pregnancy in the early stages. Angiogenesis is responsible for these essential processes. This study aimed to investigate dill seed oil’s cytotoxic and antiangiogenic effects on rat adipose tissue endothelial cells (RATECs). Dill seed oil showed dose-dependent cytotoxicity on RATECs. It disrupted endothelial tube formation and depolymerized F-actin stress fibers. According to this study, depolymerization of F-actin stress fiber by dill seed oil could inhibit angiogenesis by suppressing endothelial cell proliferation, tube formation and motility. In other words, dill seed oil can be a new anti-angiogenic agent and a novel contraceptive

Changes on cell surface and microfilament distribution during myoblast differentiation and transformation in vitro

15th Annual Meeting of the Japanese-Association-for-Animal-Cell-Technology -- NOV 11-15, 2002 -- Fuchu, JAPANWOS: 000222558600084A myoblast cells that normally differentiated into myotubes are diverted into cell proliferetion following the activity of an oncogene. In this study, we have examined the CO25 myoblast cell line which are transfected human N-ras oncogene at different stage in the biological processes as differentiation and transformation for morphological and cytoskeletal changes. The phase contrast, fluorescence and scanning electron microscope were used for organization of the cell shape, details of the surface and microfilament organization. Certain differentiation were determined on the surface of cells, shape of the cells and also cytoplasmic cytoskeletal distribution between differentiated and transformed cells in different culture media.Japanese Assoc Anim Cell Techno

Primary cilium in CO25 cell line

15th Annual Meeting of the Japanese-Association-for-Animal-Cell-Technology -- NOV 11-15, 2002 -- Fuchu, JAPANWOS: 000222558600085A few variety of cell type contain a primary cilium. Also the biological function(s) of primary cilia within such cell types are largely unknown. CO25 myoblast cell lines were cultured then they were stained with anti Glu- and Tyr- tubulin in this study. Glu-tubulin rich microtubules were only rarely seen in the cells. But the primary cilia was strongly stained by anti Glu-tubulin and also they were usually showed some weak staining with the anti Tyr-tubulin stain. Usually the differentiating myoblast cells had one primary cilium which has always localized over the top of the nuclei. The primary cilia always had a wider base and the botom the shaft was thicker than the upper part. Cytoplasmic microtubules have reorganized and also primary cilium has formed after replacing of centrioles in progression of myogenesis.Japanese Assoc Anim Cell Techno

Inhibitory effects of carvacrol on DMBA induced pulmonary tumorigenesis in rats

Essential oils of various plant species rich in carvacrol have several ethnomedical uses for various diseases in Turkey. Carvacrol, which was obtained by fractional distillation of Origanun onites L essential oil was tested for lung tumors induced by DMBA in rats in vivo and it was found to have strong antitumor activity at 0.1 mg·kg-1 i.p. Although the mechanism of action of antitumor activity of carvacrol was not investigated in this study, evidences for an inhibitory effect on angiogenesis were observed