Apoptotic Cell Number (apoptotic + cell_number)

Distribution by Scientific Domains


Selected Abstracts


Dose-Dependent Immunohistochemical Changes in Rat Cornea and Retina after Oral Methylphenidate Administration

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2 2009
E. Tunc
Summary Methylphenidate hydrochloride (MPH), more commonly known as Ritalin, is a piperidine derivative and is the drug most often used to treat attention deficit/hyperactivity disorder, one of the most common behavioural disorders of children and young adults. The aim of this study was to investigate dose-dependent immunohistochemical Dopamine 2 receptor (D2) expression and apoptosis in the rat cornea and cornea. In this study, 27 female pre-pubertal Wistar albino rats, divided into three different dose groups (5, 10 and 20 mg/kg) and their control groups, were used. They were treated orally with methylphenidate dissolved in saline solution for 5 days per week during 3 months. At the end of the third month, after perfusion fixation, eye tissue was removed. Paraffin sections were collected for immunohistochemical and terminal deoxynucleotidyl-transferase-mediated dUTP-biotin nick end labelling assay studies. In our study, we observed that the cornea D2 receptor reactivity showed a dose-related increase after MPH treatment, especially in basal cells of the epithelium and a dose-dependent decrease in the retinal ganglion cell which was statistically meaningful. Analysis of the cornea thickness results showed no meaningful difference between groups. Apoptotic cell number showed a meaningful increase in the high dose treated group compared to the other groups of the study. The data suggest that Ritalin has degenerative effect on the important functional part of the eye, such as cornea and retina and its activating dopaminergic mechanism via similar neuronal paths, functionally and structurally, to induce morphological changes. As a result, we believe that this morphological changes negatively effecting functional organization of the affected cornea and retina. [source]


Effects of infection with the ectoparasite Argulus japonicus (Thiele) and administration of cortisol on cellular proliferation and apoptosis in the epidermis of common carp, Cyprinus carpio L., skin

JOURNAL OF FISH DISEASES, Issue 3 2000
A L Van Der Salm
The host-parasite interaction between juvenile carp, Cyprinus carpio, and the ectoparasitic branchiuran, Argulus japonicus, together with the role of cortisol in this interaction, was examined at the level of the host skin epidermis. Epidermal mucous cell numbers, and proliferation and apoptosis of the epithelial cells were studied over 32 days. Apoptotic cell numbers in the uppermost epidermis were reduced at 26 days post-infection with A. japonicus, while the other parameters were unaffected. Administration of cortisol-containing food resulted in reduced apoptosis in the cells in the upper skin epidermis at 24 h and at 28 days post-feeding. Cortisol feeding combined with A. japonicus infection reduced numbers of apoptotic cells in the upper epidermis more than either individual treatment. Further, combining the treatments also significantly increased apoptosis in the lower epidermis in cells morphologically identified as leucocytes apparently migrating macrophages and lymphocytes. Using immunohistochemistry, we demonstrated cortisol receptor presence and cellular localization in the teleost epidermis. Receptors only occurred in pavement cells in the upper epidermis and in leucocytes in the lower parts of the epidermis. The ectoparasites, or administered cortisol, induced effects which may be functionally adaptive in the upper pavement cells, while combining the two treatments also induced changes indicative of immunosuppression. [source]


Sex Differences and the Roles of Sex Steroids in Apoptosis of Sexually Dimorphic Nuclei of the Preoptic Area in Postnatal Rats

JOURNAL OF NEUROENDOCRINOLOGY, Issue 4 2009
S. Tsukahara
The brain contains several sexually dimorphic nuclei that exhibit sex differences with respect to cell number. It is likely that the control of cell number by apoptotic cell death in the developing brain contributes to creating sex differences in cell number in sexually dimorphic nuclei, although the mechanisms responsible for this have not been determined completely. The milieu of sex steroids in the developing brain affects sexual differentiation in the brain. The preoptic region of rats has two sexually dimorphic nuclei. The sexually dimorphic nucleus of the preoptic area (SDN-POA) has more neurones in males, whereas the anteroventral periventricular nucleus (AVPV) has a higher cell density in females. Sex differences in apoptotic cell number arise in the SDN-POA and AVPV of rats in the early postnatal period, and an inverse correlation exists between sex differences in apoptotic cell number and the number of living cells in the mature period. The SDN-POA of postnatal male rats exhibits a higher expression of anti-apoptotic Bcl-2 and lower expression of pro-apoptotic Bax compared to that in females and, as a potential result, apoptotic cell death via caspase-3 activation more frequently occurs in the SDN-POA of females. The patterns of expression of Bcl-2 and Bax in the SDN-POA of postnatal female rats are changed to male-typical ones by treatment with oestrogen, which is normally synthesised from testicular androgen and affects the developing brain in males. In the AVPV of postnatal rats, apoptotic regulation also differs between the sexes, although Bcl-2 expression is increased and Bax expression and caspase-3 activity are decreased in females. The mechanisms of apoptosis possibly contributing to the creation of sex differences in cell number and the roles of sex steroids in apoptosis are discussed. [source]


Insulin-like growth factor-I ameliorates demyelination induced by tumor necrosis factor-, in transgenic mice

JOURNAL OF NEUROSCIENCE RESEARCH, Issue 4 2007
Ping Ye
Abstract Our groups have reported that tumor necrosis factor-, (TNF-,) causes myelin damage and apoptosis of oligodendrocytes and their precursors in vitro and in vivo. We also have reported that insulin-like growth factor-I (IGF-I) can protect cultured oligodendrocytes and their precursors from TNF-,-induced damage. In this study, we investigated whether IGF-I can protect oligodendrocytes and myelination from TNF-,-induced damage in vivo by cross-breeding TNF-, transgenic (Tg) mice with IGF-I Tg mice that overexpress IGF-I exclusively in brain. At 8 weeks of age, compared with those of wild-type (WT) mice, the brain weights of TNF-, Tg mice were decreased by ,20%, and those of IGF-I Tg mice were increased by ,20%. The brain weights of mice that carry both TNF-, and IGF-I transgenes (TNF-,/IGF-I Tg mice) did not differ from those of WT mice. As judged by histochemical staining and immunostaining, myelin content in the cerebellum of TNF-,/IGF-I Tg mice was similar to that in WT mice and much more than that in TNF-, Tg mice. Consistently, Western immunoblot analysis showed that myelin basic protein (MBP) abundance in the cerebellum of TNF-,/IGF-I Tg mice was double that in TNF-, Tg mice. In comparison with WT mice, the number of oligodendrocytes was decreased by ,36% in TNF-, Tg mice, whereas it was increased in IGF-I Tg mice by ,40%. Oligodendrocyte number in TNF-,/IGF-I Tg mice was almost twice that in TNF-, Tg mice. Furthermore, IGF-I overexpression significantly reduced TNF-,-induced increases in apoptotic cell number, active caspase-3 abundance, and degradaion of MBP. Our results indicate that IGF-I is capable of protecting myelin and oligodendrocytes from TNF-,-induced damage in vivo. © 2007 Wiley-Liss, Inc. [source]


Identification of stemonamide synthetic intermediates as a novel potent anticancer drug with an apoptosis-inducing ability

INTERNATIONAL JOURNAL OF CANCER, Issue 2 2010
Ying-Yi Li
Abstract We previously demonstrated that Pim-3, a protooncogene with serine/threonine kinase activity, was aberrantly expressed in malignant lesions but not in normal tissues of endoderm-derived organs, including pancreas, liver, colon and stomach. Moreover, aberrantly expressed Pim-3 can prevent tumor cell apoptosis by inactivating a proapoptotic molecule, Bad, and enhancing the expression of an antiapoptotic molecule, Bcl-XL. These observations prompted us to speculate that a chemical targeting Pim-3 kinase may be a good candidate for a novel type of anticancer drug. Hence, we screened various low-molecule compounds by examining their capacity to inhibit Pim-3 kinase activity in vitro. We observed that some synthetic intermediates of stemonamide can inhibit in vitro activities of Pim-3 kinase and its related kinases, such as Pim-1 and Pim-2. Moreover, these compounds inhibit in vitro cell proliferation of various human pancreatic, hepatocellular and colon cancer cell lines. Furthermore, the compounds can induce apoptosis of human pancreatic cancer cell lines in vitro by reducing the amount of phospho-Ser112 -Bad, but not total amounts of Bad and Pim-3. Finally, when the compound was administered to nude mice injected with a human pancreatic cancer cell line, it retarded tumor growth by increasing apoptotic cell numbers and decreasing proliferating cell numbers without causing serious adverse effects on blood counts. These observations indicate that the chemicals and its related compounds may be effective for the treatment of tumors of endoderm-derived organs, particularly the pancreas. [source]