Effects of cyclosporin, nifedipine and phenytoin on gingival myofibroblast transdifferentiation in monkeys

Abstract Objective: Myofibroblasts have been associated with the development of several pathologic fibrotic conditions. This longitudinal study aims to assess the proliferative and antiapoptotic effects of cyclosporin, nifedipine and phenytoin on gingival connective tissue cells of nonhuman primate, as well as to analyze a possible role of myofibroblasts in gingival overgrowth. Materials and Methods: Gingival samples from the right superior canine area were obtained from 12 male monkeys ( Sapajus spp ) to comprise the control group. After one week, the animals were randomly assigned to three groups, which received daily oral doses of cyclosporin, nifedipine or phenytoin for 120 days. Gingival samples were collected from the left superior canine area of two animals of each group at 52 and 120 days. Histological sections were stained with hematoxylin and eosin, and immunoreacted against α-SMA, Ki- 67 and bcl-2. Results: α-SMA immunoreaction was negative in the control and experimental groups. Similarly, no difference between groups concerning immunostaining against Ki-67 and bcl-2 was observed in connective tissue cells. Conclusion: Based on this methodology, it may be concluded that gingival overgrowths induced by cyclosporin, nifedipine and phenytoin are not associated with neither myofibroblast transdifferentiation, proliferation nor apoptosis of gingival connective cells in monkeys.

Immunoexpression of vascular endothelial growth factor and B-cell lymphoma 2 in the uterine tissue of rats treated with melatonin in the estrus phase

Abstract Purpose: To investigate the effect of melatonin on uterine tissue in the ovariectomized rat model. Methods: Fourty Wistar albino rats were divided into four groups for histologic and immunohistochemical examination. The rats were first numbered randomly and then randomly divided into 4 equal groups: control (group 1), torsion (group 2), torsion+detorsion (group 3) and torsion+detorsion+melatonin (group 4) groups. In addition, four Wistar albino rats were used for western blot analysis in each group. And also, malondialdehyde (MDA) levels were measured biochemically in all rats. Results: The histopathological examination of the uterine tissue in rats ovarectomized showed a degeneration in uterine glands, dilation of blood vessels in the internal layer with a thrombosis and bleeding, abnormal nucleuses and vacuolated cytoplasm above and below the nucleus. In torsion group, the apoptotic cells increased in luminal epithelium and gland cells. In the melatonin group showed that the Bcl2 negative effect on the uterine epithelium and did not lead to apoptotic cells. Conclusion: The increase in vascular endothelial growth factor expression resulted in the rearrangement of endothelial cell growth and the induction of angiogenesis.

Effect of pentoxifylline on bcl-2 gene expression changes in hippocampus after ischemia-reperfusion in wistar rats by a quantitative RT-PCR method

Ischemia-reperfusion injury is the tissue damage caused when blood supply returns to the tissue after a period of ischemia or lack of oxygen. Ischemia-reperfusion brain injury initiates an inflammatory response involving the expression of adhesion molecules and cytokines. Twenty-four male Wistar rats [250-300 g body wt] were used in this study. The animals were divided into four groups of 6 rats each: I: Control group that was subjected to ischemia-reperfusion, II: Ischemia-reperfusion group that was subjected to all surgical procedures, III: Drug group that received pentoxifylline [200, 400 and 600 mg/kg] 60 min before and after ischemia and IV: Vehicle group that received saline. Seventy two h after ischemia-reperfusion, the hippocampus was taken for studying the changes in bcl-2 gene expression. We used quantitative real-time PCR for the detection of bcl-2 gene expression in ischemia and drug groups and then compared them to normal samples. The results showed the gene dosage ratio of 0.66 and 1.5 for ischemia group and the drug groups, respectively. The results also showed the bcl-2 gene expression declined in ischemia group as compared to the drug group. Furthermore, we observed a significant difference in the bcl-2 gene expression between ischemia and drug groups. These findings are consistent with anti-apoptotic properties of bcl-2 gene. Furthermore this method provides a powerful tool for the investigators to study brain ischemia and respond to the treatment drugs with anti-apoptotic agents

CD95 and BCL-2 expression as apoptotic markers in rheumatoid arthritis patients

Dysregulation of apoptosis of the different immune cells including the peripheral blood mononuclea, cells [PBMNC], lymphocytes have been incriminated as a pathogenetic factor in rheumatoid arthrjts [RA]. CD95 [Fas] as a death receptor and Bcl-2 as an antiapoptotic protein are among the important factors responsible for controlling lymphocytes apoptosis. To assess the expression of CD95 and Bcl-2 as apoptotic markers in PBMNs in RA patients and correlate them with RA activity and functional capacity of RA patients. Twenty RA patients and 10 healthy controls were included in this study. All patients were maintained on 7.5 mg methotrexate /week and concomitant NSAIDs. All patients were examined clinically and disease activity measures including Ritchie articular index [RAI] and the number of swollen joints [SW44] were assessed and disease activity score [DAS] was calculated for each patient. Health assessment questionnaire [HAQ] was also determined. CD95 and Bcl-2 expression on the PBMNC were assessed in serum samples by flow cytometry in patients and controls, in addition to complete blood count, Rose Waaler test and ESR. Plain X-ray for both hands was also performed for all patients to detect joint erosions. The mean CD95 expression on PBMNC was significantly higher in RA patients compared to healthy controls [t=3.222, P= 0.004]. CD95 was also significantly and positively correlated with RAI, [DAS] and [ESR] [r=0.463, r=0.736, r=0.542 respectively and P<0.05 for all]. There was no statistically significant difference regarding the mean expression of Bcl-2 in RA patients and controls [t=0.122, P>0.05]. It did not also correlate with any of the studied variables. Increased CD95 expression on PBMNC in RA patients seems to be related to the inflammatory process [disease activity] in rheumatoid disease rather than to the apoptotic process as it is correlated with disease activity measures of the studied patients. Moreover, the normal expression of Bcl-2 in PBMNC indicated that the possibility of dysregulation of apoptosis in this study is unlikely

Molecular analysis of Bcl-2 and cyclin Dl expression in differentially expressing estrogen receptor breast cancer MCF7, T47D and MDA-MB-468 cell lines treated with adriamycin

Bcl-2 and Cyclin Dl [CCND1] are key elements in cancer development and progression. Bcl-2 acts as a cell death suppressor and is involved in apoptosis regulation. Cyclin Dl is an important regulator of Gl/S phase of the cell cycle progression. In addition, estrogen receptor [ER] is an important prognostic factor in breast cancer cells. Therefore it is important to determine the Bcl-2 and CCND1 expression in MCF7, T47D and MDA-MB-468 breast cancer cell lines with different ER status following Adriamycin [ADR] treatment. Cytotoxicity of ADR [250 and 500nM] after 1-5 days exposure of the cell lines was evaluated by MTT assay. The mRNA and protein levels of Bcl-2 and cyclin Dl in tested cell lines were also analyzed by RT-PCR and immunocytochemistry [ICC] methods ADR cytotoxicity was highest in MDA-MB-468 and lowest in MCF7 cells in a time-dependent manner. Bcl-2 mRNA increased in MCF7 and decreased in MDA-MB-468 after exposure to ADR but it was less detectable in T47D cells. The expression of CCND1 in MCF7 with high level of ER expression was higher than the other two cell lines in untreated conditions. However, CCND1 mRNA did not show significant changes after ADR treatment. Immunocytochemical analysis did not show significant differences between Bcl-2 protein expression in the presence or absence of ADR in MDA-MB-468 cell line while in T47D and MCF7 cells its expression decreased after exposure to ADR. In addition to nuclear expression of cyclin Dl in all cell lines, strong cytoplasmic expression of cyclin Dl protein was observed only in MCF7 and T47D cells. The tested cell lines with different levels of ER expression showed differential molecular responses to ADR that is important in tumor-targeted cancer therapy

Arsenic trioxide in the management of acute promyelocytic leukaemia.

Arsenical compounds were used as early as 2000 BC, both as medicines as well as poisons. Arsenicals gained importance in the beginning of the last century as the primary mode of treating syphilis. In 1931, Folkner and Scott used an arsenical preparation called Fowler's solution in the treatment of chronic myeloid leukaemia. This continued to be used until the introduction of busulphan in 1953. In the 1970s, arsenic trioxide was introduced for the treatment of acute promyelocytic leukaemia in China and was found to be extremely effective in treating this condition. Since then, numerous in vitro and in vivo studies have confirmed this observation. This article reviews the pathogenesis of acute promyelocytic leukaemia, the possible mechanism of action of arsenic trioxide in this condition and the literature on its use in the treatment, with special reference to the clinical and molecular response rates, toxicity and pharmacology of this compound. It also attempts to address the role of arsenic trioxide in the present algorithm for the treatment of acute promyelocytic leukaemia.