Human cardiac multipotent adult stem cells in 3D matrix: new approach of tissue engineering in cardiac regeneration post-infarction.

Myocardial infarction is the leading cause of morbidity and mortality in developed countries. It causes a left ventricular dysfunction, mainly due to the loss of functional tissue, resulting in heart failure. New therapies are being developed, using a tissue engineering approach, with the ultimate goal of restoring cardiac function by regenerating and repairing the damaged myocardium. In the present study we investigated the behaviour of a specific population of c-kit positive human cardiac stem cells, called Multipotent Adult Stem Cells (MASCs), grown within three-dimensional collagen scaffolds (3D), to establish whether they could be used in post-infarction cardiac regeneration. We also evaluated the expression levels of the Granulocyte Macrophage-Colony Stimulating Factor Receptor (GM-CSFR) and endoglin, a component of the Transforming Growth Factor beta (TGF-ß) receptor complex. Finally, we also evaluated the expression of the α2ß1integrin. MASCs cultured within 3D collagen matrices are able to proliferate and migrate even in the absence of chemotactic agents and express high levels of factors involved in cell proliferation and migration, such as GM-CSFRα chain and integrins. They therefore represent a promising approach to tissue engineering aimed to restore cardiac function. Our results also suggest a role of GM-CSF in cell proliferation, while TGF-ß does not seem to be relevant.

High incidence of MTHFR, CBS, and MTRR polymorphisms in vitiligo patients. Preliminary report in a retrospective study.

OBJECTIVE: Vitiligo is a multifactorial polygenic disorder with a complex pathogenesis. It is related to both genetic and no genetic factors. The role of genetics is currently studied with several analytical approaches, such as genetic linkage, candidate gene association studies, genome-wide association studies (GWAS), deep DNA re-sequencing and gene expression studies. To date, there are no genetic traits directly related to vitiligo pathogenesis. PATIENTS AND METHODS: 43 cases of vitiligo patients and 30 healthy donors recruited as control, were screened by assaying the biochemical molecules involved in the self-cells cytotoxicity (haptoglobin and homocysteine) and candidate genes involved in the regulatory process of the re-methylation cycles and transsulfuration. Candidate genes and their polymorphisms screened are methylene-tetrahydrofolate-reductase (MTHFR) C677T and A1298C; cystathionine-beta-synthase enzyme (CBS) I278T and Ins68bp; and methionine-synthase-reductase (MTRR) A66G. RESULTS: A peculiar genetic profile in vitiligo patients are defined: 11.6% of vitiligo patients shown polymorphic variant MTHFR 677TT vs. 3.3% of healthy donor MTHFR 677CC profile (p=0.0017); 14.0% of vitiligo patients shown CBS polymorphic variant 278TT vs. 3.3% of healthy donor 278II profile (p=0.0012); and 11.6% of vitiligo patients shown MTRR 66GG vs. 3.3% of healthy donor MTRR 677AA profile (p>0.0001). CONCLUSIONS: This is the first study reporting the correlation between the polymorphic status of MTHFR C677T, CBS I278T, and MTRR A66G and vitiligo. The genetic screening of these polymorphisms could be useful for early detection of the inheritance risk factor in a subject carrying relatives with vitiligo. Although these data could suggest a kind of dysregulation, genetically based, of thiols production mechanisms. Based on these results, we have not been able to get hypothesis about the putative pathogenesis of vitiligo, and the precise cause remains unclear.

Evaluation of Propineb, a dithiocarbamate pesticide, in the mouse-sperm morphology assay.

Propineb, a dithiocarbamate fungicide, was studied by using the sperm morphology assay in (C57BL6 male X C3H female) F1 mice. At all dose levels, no statistically significant increase in the percentage of sperm abnormalities was observed. Methyl methanesulfonate (MMS) and 2-acetylaminofluorene (2-AAF), which were tested as positive controls, induced a dose-effect-related increase in teratospermia.

Dithiocarbamate pesticides: activity of Propineb in the micronucleus test in mice.

The possible clastogenic activity of Propineb, Propineb technical grade and of its main metabolite, propylene-thiourea (PLTU), was investigated by the micronucleus test in mice according to Schmid. No statistically significant increase in the percentage of micronuclei was observed at any of the tested doses of the above compounds. As positive controls, dose-effect curves were constructed for methyl methanesulfonate (MMS) and mitomycin C (MMC).

Biological availability of mutagenic compounds adsorbed onto diesel exhaust particulate.

Diesel particles were collected from the exhaust of a VW Golf diesel car by electrostatic precipitation. The particulate and its DCM extract were highly mutagenic in the Salmonella/microsome test in the presence and absence of metabolic activation; the highest response was observed with TA98 and TA1538 tester strains. The biological availability of particulate-associated mutagenic compounds was demonstrated by administering powder to rats and assaying, in vitro, the urine excreted within 24 h after treatment. The highest activity was obtained with TA98 in the presence of metabolic activation. Typical dose-effect responses were evident in urine of animals treated by all the administration routes tested (i.p., s.c. and per os), both in the presence and absence of a suspending vehicle. Concentration of mutagenic compounds present in urine of treated animals could be achieved by chromatography on Amberlite XAD-2 and XAD-7 resins. This study provides direct evidence for bioavailability to animal tissues of mutagens adsorbed onto diesel particulate, although part of the activity might be ascribed to nitroaromatic compounds formed during the collection of the powder. The present study is part of a more comprehensive work on diesel exhaust particulate, and results have to be considered in this light before any final conclusion can be drawn.

Effect of DNOC, Ferbam and Imidan exposure on mouse sperm morphology.

DNOC, Ferbam and Imidan were tested in (C3H X C57BL/6) F1 mice to assess their potential testicular toxicity. Chemicals were administered i.p. and per os at different doses for 5 consecutive days. After 35 days the testicular was toxicity was evaluated by measuring the testicular weights, the sperm counts and the percentage of abnormal sperm. DNOC and Imidan failed to induce teratospermia in mice treated by both routes of administration. Conversely Ferbam induced a statistically significant increase in teratospermia only following per os administration to mice at a dose of 1000 mg/kg b.w./day. These data indicate that per os administration of Ferbam succeeded in producing active metabolites able to interfere with the differentiation process of spermatogenic cells.

Induction of sperm abnormalities in mice by ifosfamide and trofosfamide.

The antitumor drugs ifosfamide (IF) and trofosfamide (TF) were evaluated for their capability to induce sperm abnormalities in (C3H X C57BL/6)F1 mice. A statistically significant increase in teratospermia was observed at the 35th day after 5 daily consecutive intraperitoneal injections of the drugs at doses of 25, 50, 100 mg/kg b.w. of TF and 100 mg/kg b.w. of IF. Thus, IF and TF are able to interfere with the differentiation process of spermatogenic cells.

Neuroglobin upregulation induced by 17ß-estradiol sequesters cytocrome c in the mitochondria preventing H2O2-induced apoptosis of neuroblastoma cells.

The sex steroid hormone 17ß-estradiol (E2) upregulates the levels of neuroglobin (NGB), a new neuroprotectant globin, to elicit its neuroprotective effect against H(2)O(2)-induced apoptosis. Several mechanisms could be proposed to justify the NGB involvement in E2 prevention of stress-induced apoptotic cell death. Here, we evaluate the ability of E2 to modulate the intracellular NGB localization and the NGB interaction with mitochondrial cytochrome c following the H(2)O(2)-induced toxicity. Present results demonstrate that NGB is expressed in the nuclei, mitochondria, and cytosol of human neuroblastoma SK-N-BE cells. E2, but not H(2)O(2) treatment of SK-N-BE cells, reallocates NGB mainly at the mitochondria and contemporarily reduces the number of apoptotic nuclei and the levels of cleaved caspase-3. Remarkably, the E2 treatment strongly increases NGB-cytochrome c association into mitochondria and reduces the levels of cytochrome c into the cytosol of SK-N-BE cells. Although both estrogen receptors (ERα and ERß) are expressed in the nucleus, mitochondria, and cytosol of SK-N-BE cells, this E2 effect specifically requires the mitochondrial ERß activity. As a whole, these data demonstrate that the interception of the intrinsic apoptotic pathway into mitochondria (i.e., the prevention of cytochrome c release) is one of the pivotal mechanisms underlying E2-dependent NGB neuroprotection against H(2)O(2) toxicity.

17ß-Oestradiol anti-inflammatory effects in primary astrocytes require oestrogen receptor ß-mediated neuroglobin up-regulation.

Neuroglobin (Ngb), so named after its initial discovery in brain neurones, has received great attention as a result of its neuroprotective effects both in vitro and in vivo. Recently, we demonstrated that, in neurones, Ngb is a 17ß-oestradiol (E(2) ) inducible protein that is pivotal for hormone-induced anti-apoptotic effects against H(2) O(2) toxicity. The involvement of Ngb in other brain cell populations, as well as in other neuroprotective effects of E(2) , is completely unknown at present. We demonstrate Ngb immunoreactivity in reactive astrocytes located in the proximity of a penetrating cortical injury in vivo and the involvement of Ngb in the E(2) -mediated anti-inflammatory effect in primary cortical astrocytes. Upon binding to oestrogen receptor (ER)ß, E(2) enhances Ngb levels in a dose-dependent manner. Although with a lesser degree than E(2) , the pro-inflammatory stimulation with lipopolysaccharide (LPS) also induces the increase of Ngb protein levels via nuclear factor-(NF)κB signal(s). Moreover, a negative cross-talk between ER subtypes and NFκB signal(s) has been demonstrated. In particular, ERα-activated signals prevent the NFκB-mediated Ngb increase, whereas LPS impairs the ERß-induced up-regulation of Ngb. Therefore, the co-expression of both ERα and ERß is pivotal for mediating E(2) -induced Ngb expression in the presence of NFκB-activated signals. Interestingly, Ngb silencing prevents the effect of E(2) on the expression of inflammatory markers (i.e. interleukin 6 and interferon γ-inducible protein 10). Ngb can be regarded as a key mediator of the different protective effects of E(2) in the brain, including protection against oxidative stress and the control of inflammation, both of which are at the root of several neurodegenerative diseases.

[Teratogenic and goitrogenic activity of propineb and propylenethiourea in the rat]. / Attività teratogena e gozzigena di propineb e propilentiourea nel ratto.

The teratogenic and goitrogenic effects of Propineb, dithiocarbamate pesticide and Propylenthiourea (PLTU), its metabolite and degradation product have been studied. The aim of this study was to show the possible correlation between the two activities. Female Sprague-Dawley rats were treated with Propineb and PLTU starting from 6th to 16th day of pregnancy. The functional state of maternal and foetal thyroid, the toxicity of products versus dams and embryotoxic and teratogenic effects were examined. The observed goitrogenic effect may be compared to that reported in the previous studies of the authors, if considering time of sacrifice. In fact, the lesion quickly rises and as rapidly regresses when treatment is stopped. The foetal thyroid has not been affected by the product administered to the dams. PLTU showed a clear teratogenic activity at doses that did not show any maternal toxicity (45 and 90 mg/k).