Raffaella Adami

Embryonic stem cells promote motor recovery and affect inflammatory cell infiltration in spinal cord injured mice.

The purpose of this study was to determine the fate and the effects of undifferentiated embryonic stem cells (ESCs) in mice after contusive lesion of the spinal cord (SCI). Reproducible traumatic lesion to the cord was performed at T8 level by means of the Infinite Horizon Device, and was followed by intravenous injection of one million of undifferentiated ESCs through the tail vein within 2 h from the lesion. The ESCs-treated animals showed a significant improvement of the recovery of motor function 28 days after lesion, with an average score of 4.61+/-0.13 points of the Basso Mouse Scale (n=14), when compared to the average score of vehicle treated mice, 3.58+/-0.23 (n=10). The number of identified ESCs found at the lesion site was 0.6% of the injected cells at 1 week after transplantation, and further reduced to 0.04% at 1 month. It is, thus, apparent that the promoted hind-limb recovery cannot be correlated to a substitution of the lost tissue performed by the exogenous ESC. The extensive evaluation of production of several neuroprotective and inflammatory cytokines did not reveal any effect by ESC-treatment, but unexpectedly the number of invading macrophages and neutrophils was greatly reduced. This may explain the improved preservation of lesion site ventral myelin, at both 1 week (29+/-11%) and 1 month (106+/-14%) after injury. No teratoma formation was observed, although an inappropriate colonization of the sacral cord by differentiated nestin- and beta-tubulin III-positive ESCs was detected.

Third trimester amniotic fluid cells with the capacity to develop neural phenotypes and with heterogeneity among sub-populations

PURPOSE Our aim was the search for new sources of cells potentially useful for central nervous system regenerative medicine. Extra-embryonic tissues are promising sources of pluripotent stem cells. Among these, human second-trimester amniotic fluid (AF) contains cell populations exhibiting self-renewal capacity, multipotency and the expression of embryonic cell markers. METHODS Here we report the properties of the easily available third-trimester AF cells (AFCs). Different cell types from 6 of 9 AF samples were separated, expanded, and characterized by assessing their morphological, proliferative, and differentiative properties. RESULTS All isolated cultures presented CD105, CD90 and CD73 mesenchymal markers, whereas they differed among themselves in CD117, CD146, CD31, NG2 and CD133 expression. Their doubling time and telomere length were conserved throughout many passages. Importantly, immunofluorescence and Real-time PCR showed that, during their proliferative state and differentiation, several cultures expressed neuronal and glial markers such as nestin, GFAP, β-tubulin III and neurofilament H indicating their potential attitude towards a neural fate. Indeed, these cells showed a rather poor capacity to differentiate in adipogenic and osteogenic lineages. CONCLUSIONS In this work we report that cells with neural differentiation capability can be isolated from third-trimester AF, such properties could be useful for neuro-regenerative purposes.

Third trimester NG2-positive amniotic fluid cells are effective in improving repair in spinal cord injury.

Spinal cord injury presents a significant therapeutic challenge since the treatments available are mostly vain. The use of stem cells to treat this condition represents a promising new therapeutic strategy; therefore, a variety of stem cell treatments have been recently examined in animal models of CNS trauma. In this work, we analyzed the effects of third trimester amniotic fluid cells in a mouse model of spinal cord injury. Among the different cultures used for transplantation, some were able to induce a significant improvement in motor recovery (cultures #3.5, #3.6 and #7.30), evaluated by means of open field free locomotion. All effective cell cultures expressed the surface marker nerve/glial antigen 2, ortholog of the human chondroitin sulfate proteoglycan 4, which is present on several types of immature progenitor cells. The improved motor functional recovery was correlated with higher myelin preservation in the ventral horn white matter and an increased vascularization in the peri-lesion area. Real-Time PCR analysis showed higher expression levels of vascular endothelial growth factor and hypoxia-inducible factor-1α mRNA two days after cells transplantation compared to PBS-treated animals, indicating that an angiogenic pathway might have been activated by these cells, possibly through the production of hepatocyte growth factor. This cytokine appears to be produced mostly in filtering organs, such as the lung, of the transplanted animals and is likely released in the blood suggesting an endocrine role of hepatocyte growth factor in targeting the injury site.

Stem cell transplantation in neurological diseases: improving effectiveness in animal models.

Neurological diseases afflict a growing proportion of the human population. There are two reasons for this: first, the average age of the population (especially in the industrialized world) is increasing, and second, the diagnostic tools to detect these pathologies are now more sophisticated and can be used on a higher percentage of the population. In many cases, neurological disease has a pharmacological treatment which, as in the case of Alzheimers disease, Parkinsons disease, Epilepsy, and Multiple Sclerosis can reduce the symptoms and slow down the course of the disease but cannot reverse its effects or heal the patient. In the last two decades the transplantation approach, by means of stem cells of different origin, has been suggested for the treatment of neurological diseases. The choice of slightly different animal models and the differences in methods of stem cell preparation make it difficult to compare the results of transplantation experiments. Moreover, the translation of these results into clinical trials with human subjects is difficult and has so far met with little success. This review seeks to discuss the reasons for these difficulties by considering the differences between human and animal cells (including isolation, handling and transplantation) and between the human disease model and the animal disease model.

Spinal muscular atrophy: new findings for an old pathology.

Understanding the events that are responsible for a disease is mandatory for setting up a therapeutic strategy. Although spinal muscular atrophy (SMA) is considered a rare neurodegenerative pathology, its impact in our society is really devastating as it strikes young people from birth onward, and it affects their families either emotionally or financially. Moreover, it requires intensive care for the children, and this diverts both parents and relatives from their occupations. Each neuron is very different from one another; therefore, in a neurodegenerative disease, the population of axons, synapses and cell bodies degenerate asynchronously, and subpopulations of neurons have different vulnerabilities. The knowledge of the sequence of events along the lengths of individual neurons is crucial to understand if each synapse degenerates before the corresponding axon, or if each axon degenerates before the corresponding cell body. Early degeneration of one neuronal compartment in disease often reflects molecular defects somewhere else. Up until now, SMA is considered mostly a lower motor neuron disease caused by the loss‐of‐function mutations in the SMN1 gene; here, we inspect other features that can be altered by this defect, such as the cross talk between muscle and motor neuron and the role of physical inactivity.

Myriocin treatment of CF lung infection and inflammation: complex analyses for enigmatic lipids

Our aim was to use quantitative and qualitative analyses to gain further insight into the role of ceramide in cystic fibrosis (CF). Sphingolipid ceramide is a known inflammatory mediator, and its accumulation in inflamed lung has been reported in different types of emphysema, chronic obstructive pulmonary disease and CF. CF is caused by a mutation of the chloride channel and associated with hyperinflammation of the respiratory airways and high susceptibility to ongoing infections. We have previously demonstrated that de novo ceramide synthesis is enhanced in lung inflammation and sustains Pseudomonas aeruginosa pulmonary infection in a CF murine model. We used liquid chromatography and matrix-assisted laser desorption/ionization (MALDI) imaging coupled with mass spectrometry, confocal laser scan microscopy and histology analyses to reveal otherwise undecipherable information. We demonstrated that (i) upregulated ceramide synthesis in the alveoli is strictly related to alveolar infection and inflammation, (ii) alveolar ceramide (C16) can be specifically targeted by nanocarrier delivery of the ceramide synthesis inhibitor myriocin (Myr) and (iii) Myr is able to downmodulate pro-inflammatory lyso-PC, favouring an increase in anti-inflammatory PCs. We concluded that Myr modulates alveolar lipids milieu, reducing hyperinflammation and favouring anti-microbial effective response in CF mouse model.

Movement impairment: Focus on the brain.

The saying “mens sana in corpore sano” has a particular resonance these days because, for the majority who have a very sedentary occupation, the everyday rhythms of life do not compel us to do much physical exercise. Recently published data indicate that exercise can counteract the effects of neurological diseases such as Alzheimers disease and have prompted research on the beneficial effects of movement on the brain and brain neurogenesis. This might lead us to hypothesize that the absence or reduction of movements, especially those with antigravity effects, could induce a deterioration of the brain. This Review discusses current knowledge of the relationship between neurogenic capacity and the lack of motor activity in human and animal models.

Glycosphingolipids and Neural Stem Cells

Until a few years ago, the majority of cell functions were envisioned as the result of protein and DNA activity. The cell membranes were considered as a mere structure of support and/or separation. In the last years, the function of cell membranes has, however, received more attention and their components of lipid nature have also been depicted as important cell mediators and the membrane organization was described as an important determinant for membrane‐anchored proteins activity. In particular, because of their high diversity, glycosphingolipids offer a wide possibility of regulation. Specifically, the role of glycosphingolipids, in the fine‐tuning of neuron activity, has recently received deep attention. For their pivotal role in vertebrate and mammals neural development, neural stem cells regulation is of main interest especially concerning their further functions in neurological pathology progression and treatment. Glycosphingolipids expression present a developmental regulation. In this view, glycosphingolipids can hold an important role in neural stem cells features because of their heterogeneity and their consequent capacity for eclectic interaction with other cell components.

Modeling Cornelia de Lange Syndrome in vitro and in vivo reveals a role for cohesin complex in neuronal survival and differentiation

Abstract Cornelia de Lange syndrome (CdLS), which is reported to affect ˜1 in 10 000 to 30 000 newborns, is a multisystem organ developmental disorder with relatively mild to severe effects. Among others, intellectual disability represents an important feature of this condition. CdLS can result from mutations in at least five genes: nipped‐B‐like protein, structural maintenance of chromosomes 1A, structural maintenance of chromosomes 3, RAD21 cohesin complex component and histone deacetylase 8 (HDAC8). It is believed that mutations in these genes cause CdLS by impairing the function of the cohesin complex (to which all the aforementioned genes contribute to the structure or function), disrupting gene regulation during critical stages of early development. Since intellectual disorder might result from alterations in neural development, in this work, we studied the role of Hdac8 gene in mouse neural stem cells (NSCs) and in vertebrate (Danio rerio) brain development by knockdown and chemical inhibition experiments. Underlying features of Hdac8 deficiency is an increased cell death in the developing neural tissues, either in mouse NSCs or in zebrafish embryos.

Reduction of Movement in Neurological Diseases: Effects on Neural Stem Cells Characteristics

Both astronauts and patients affected by chronic movement-limiting pathologies face impairment in muscle and/or brain performance. Increased patient survival expectations and the expected longer stays in space by astronauts may result in prolonged motor deprivation and consequent pathological effects. Severe movement limitation can influence not only the motor and metabolic systems but also the nervous system, altering neurogenesis and the interaction between motoneurons and muscle cells. Little information is yet available about the effect of prolonged muscle disuse on neural stem cells characteristics. Our in vitro study aims to fill this gap by focusing on the biological and molecular properties of neural stem cells (NSCs). Our analysis shows that NSCs derived from the SVZ of HU mice had shown a reduced proliferation capability and an altered cell cycle. Furthermore, NSCs obtained from HU animals present an incomplete differentiation/maturation. The overall results support the existence of a link between reduction of exercise and muscle disuse and metabolism in the brain and thus represent valuable new information that could clarify how circumstances such as the absence of load and the lack of movement that occurs in people with some neurological diseases, may affect the properties of NSCs and contribute to the negative manifestations of these conditions.