PubMed Health⌕ Search

Biomedical subjects

M C Ingletti

Publications and source records attributed to M C Ingletti.

6 recordsLinked to original sources
PubMed1995

Sendai virus and herpes virus type 1 induce apoptosis in human peripheral blood mononuclear cells.

Recent reports suggest that several viruses, besides human immunodeficiency virus, induce apoptosis in infected cells. We report here that Sendai virus or Herpes simplex virus type 1 (HSV-1), two potent inducers of interferon-alpha, caused cell death in a consistent number of human peripheral blood mononuclear cells. A careful analysis of infected cells by different techniques, such as optical and electron microscopy, DNA agarose gel electrophoresis, and cytofluorimetric analysis of DNA content, showed that cell death was of apoptotic type. Sendai virus was more apoptogenic than HSV-1, and it was further studied to understand the mechanism(s) by which it induced apoptosis. Physical (uv and heat) and chemical (beta-propiolactone) inactivation reduced or abolished the apoptogenic power of Sendai virus. The use of a novel technique, which allows the study of mitochondrial membrane potential (MMP) in intact cells by flow cytometry, showed that a decrease of MMP is concomitant with the appearance of the hypodiploid peak. These results suggest that Sendai virus and HSV-1 can be added to the list of viruses causing apoptosis, which appears to be a general mechanism occurring during viral infection.

Apoptosis↗
PubMed1992

Regional and cellular distribution within the rat prostate of two mRNA species undergoing opposite regulation by androgens.

We have investigated, by in-situ hybridization histochemistry, the distribution within the rat ventral prostate of the mRNAs for sulphated glycoprotein-2 (SGP-2) and ornithine decarboxylase (ODC; EC 4.1.1.17), two proteins that appear to be inversely regulated by androgens in this organ, in that the level of SGP-2 mRNA is lowered, while the activity of ODC is enhanced by the latter hormones. Low-magnification autoradiograms of whole ventral prostate sections showed that, in intact animals, the SGP-2 transcript was only detectable in restricted areas and not diffused evenly throughout the section. Reciprocally, the ODC transcript was not detectable in areas where the SGP-2 transcript was detected, but appeared distributed uniformly in the remaining parts of the section. The effect of castration on the levels of the two mRNAs was evaluated by a semiquantitative analysis of autoradiograms from whole ventral prostate sections using an autoimmune image analyser. Four days after castration, SGP-2 mRNA increased by about 11-fold, while ODC mRNA decreased by fivefold. The distribution of the two mRNAs among the different cell types, studied by treating the slides with photographic emulsion and counterstaining, showed that both were expressed exclusively in the epithelial luminal cells of the ducts. Furthermore, each of the two mRNAs preferentially accumulated in a cell population which was morphologically distinct while accumulation of the other was negligible. SGP-2 mRNA was mostly found in cuboidal epithelial cells and ODC mRNA in columnar epithelial cells. Castration caused a dramatic accumulation of SGP-2 and a decrease in ODC mRNAs in the cells of the columnar epithelium 4 days later.(ABSTRACT TRUNCATED AT 250 WORDS)

Androgens↗
PubMed1991

Studies on the relationship between cell proliferation and cell death: opposite patterns of SGP-2 and ornithine decarboxylase mRNA accumulation in PHA-stimulated human lymphocytes.

To assess the relationship between cell proliferation and cell death, the mRNA accumulation of ornithine decarboxylase (ODC) and sulfated glycoprotein 2 (SGP-2) were measured in human peripheral blood lymphocytes (HPBL) 2-6 hours after stimulation with phytohemagglutinin (PHA). ODC is the rate limiting enzyme of polyamines biosynthesis and its early induction in mitogen-stimulated lymphocytes has been reported. On the other hand, SGP-2, a glycoprotein present in most mammalian tissues, is induced in classical models of apoptosis, such as dexamethasone-treated thymocytes. Indeed, a consistent amount of SGP-2 mRNA in quiescent HPBL, an early and progressive decrease of SGP-2 mRNA and a parallel increase of ODC mRNA accumulation, were observed, in PHA-stimulated HPBL, suggesting that concomitant repression of SGP-2 and induction of ODC genes contribute for the cell entering the cell cycle.

Blotting, Northern↗
PubMed1991

In vivo accumulation of sulfated glycoprotein 2 mRNA in rat thymocytes upon dexamethasone-induced cell death.

Two hours after a single intraperitoneal injection of dexamethasone (20 micrograms/Kg b.w.) into adult male rats, a typical ladder of DNA fragments was detectable upon separation on agarose gels of DNA from thymocytes. This became maximally evident at 4 hours. Accumulation of sulfated glycoprotein-2 (SGP-2) mRNA, whose rate of expression has been associated to the processes of programmed cell death, preceded the appearance of DNA degradation, starting to increase as early as 30 min after steroid injection, and maintained higher than controls until 8 hrs; a different time course was shown by changes in the levels of beta-actin mRNA. In the spleen, under the same conditions, the SGP-2 message also increased at 30 min, prior to DNA fragmentation, but decreased thereafter below the control value.

Animals↗