Rolando Campanella

Ceramide levels are inversely associated with malignant progression of human glial tumors

Ceramide represents an important sphingoid mediator involved in the signaling pathways that control cell proliferation, differentiation, and death. To determine whether ceramide levels correlate with the malignant progression of human astrocytomas, we investigated these levels in surgical specimens of glial tumors of low‐grade and high‐grade malignancy. Tumor samples obtained from 52 patients who underwent therapeutic removal of primary brain tumors were used. The tumors were classified according to standard morphologic criteria and were grouped into tumors of low‐grade and high‐grade malignancy. Sections of normal brain tissue adjacent to the tumor were also analyzed in 11 of the 52 patients. After extraction and partial purification, ceramide was measured by quantitative derivatization to ceramide‐1‐phosphate using diacylglycerol kinase and [γ‐32P]ATP. Ceramide levels were significantly lower in the combined high‐grade tumors compared with low‐grade tumors and in both tumor groups compared with peritumoral tissue. The results indicate an inverse correlation between the amount of ceramide and tumor malignancy as assessed by both the histological grading and ganglioside pattern. Moreover, overall survival analysis of 38 patients indicates that ceramide levels are significantly associated with patient survival. The present findings indicate that ceramide is inversely associated with malignant progression of human astrocytomas and poor prognosis. The downregulation of ceramide levels in human astrocytomas emerges as a novel alteration that may contribute to glial neoplastic transformation. The low ceramide levels in high‐grade tumors may provide an advantage for their rapid growth and apoptotic resistant features. This study appears to support the rationale for the potential benefits of a ceramide‐based chemotherapy. GLIA 39:105–113, 2002.

Multiple intracranial lesions in head injury: clinical considerations, prognostic factors, management, and results in 95 patients.

BACKGROUND The goal of this study was to identify clinical and radiological predictors of prognosis in patients with multiple post-traumatic intracranial lesions. METHODS We reviewed 95 patients (75 male and 20 female) between the ages of 18 and 70 (average 38) admitted between 1993 and 2000 with multiple post-traumatic intracranial lesions. Intracranial pressure (ICP) monitoring was carried out in 67 patients (70%); 77 received intensive care unit (ICU) treatment. Since in all cases it was possible to identify a clearly predominant lesion, 3 groups of patients emerged from the data: the first with extradural hematoma (EDH), the second with a combination of homolateral subdural (SDH) and intracerebral hematoma (ICH), and the third with pure focal intracerebral hematoma (ICH). RESULTS Twenty-seven patients were treated conservatively, 2 of whom died (7.4%); both had bilateral ICH and compression of the basal cisterns. Sixty-eight patients underwent one or more surgeries; 8 died (11.7%). In the group with EDH-predominant lesions (27 cases) all patients were operated (16 for multiple lesions); no one died. In the group with SDH+ICH-predominant lesions, 26 of 32 patients were operated (10 had multiple procedures); 6 died (18.7%), 3 were vegetative. In the group with ICH-predominant lesion, 15 of 36 patients were operated (7 bilaterally); 4 died (11%). Decompressive craniectomy proved to be a useful means to control ICP. Bilateral lobectomy is not recommended because of poor results. Immediate postoperative computed tomography (CT) scan proved to be mandatory to detect additional surgically treatable lesions (16 cases). Statistical analysis was performed by means of chi(2) analysis and multiple linear regression model. The multiple linear regression model was used to ascertain risk factors independently associated with the outcome. The type of lesion (presence of SDH+ICH predominant lesion), the worst recorded Glasgow Coma Scale (GCS) score, the presence of prolonged increased ICP, and the absence of pupillary reflexes were all statistically significant predictors of a bad outcome (dead or vegetative state). CONCLUSIONS Multiple lesions have the same prognosis as the corresponding single lesions; therefore, their management should be guided by the predominant pathology.

Potential use of human adipose mesenchymal stromal cells for intervertebral disc regeneration: a preliminary study on biglycan-deficient murine model of chronic disc degeneration

IntroductionBiglycan is an important proteoglycan of the extracellular matrix of intervertebral disc (IVD), and its decrease with aging has been correlated with IVD degeneration. Biglycan deficient (Bgn−/0) mice lack this protein and undergo spontaneous IVD degeneration with aging, thus representing a valuable in vivo model for preliminary studies on therapies for human progressive IVD degeneration. The purpose of the present study was to assess the possible beneficial effects of adipose-derived stromal cells (ADSCs) implants in the Bgn−/0 mouse model.MethodsTo evaluate ADSC implant efficacy, Bgn−/0 mice were intradiscally (L1-L2) injected with 8x104 ADSCs at 16 months old, when mice exhibit severe and complete IVD degeneration, evident on both 7Tesla Magnetic Resonance Imaging (7TMRI) and histology. Placebo and ADSCs treated Bgn−/0 mice were assessed by 7TMRI analysis up to 12 weeks post-transplantation. Mice were then sacrificed and implanted discs were analyzed by histology and immunohistochemistry for the presence of human cells and for the expression of biglycan and aggrecan in the IVD area.ResultsAfter in vivo treatment, 7TMRI revealed evident increase in signal intensity within the discs of mice that received ADSCs, while placebo treatment did not show any variation. Ultrastructural analyses demonstrated that human ADSC survival occurred in the injected discs up to 12 weeks after implant. These cells acquired a positive expression for biglycan, and this proteoglycan was specifically localized in human cells. Moreover, ADSC treatment resulted in a significant increase of aggrecan tissue levels.ConclusionOverall, this work demonstrates that ADSC implant into degenerated disc of Bgn−/0 mice ameliorates disc damage, promotes new expression of biglycan and increased levels of aggrecan. This suggests a potential benefit of ADSC implant in the treatment of chronic degenerative disc disease and prompts further studies in this field.

Expression of neural and neurotrophic markers in nucleus pulposus cells isolated from degenerated intervertebral disc.

Intervertebral disc (IVD) degeneration is a common disorder of the lower spine. Since it is caused by loss of cellularity, there is interest in the comprehension of the cellular phenotypes. This study aimed to verify if stem cells isolated from nucleus pulposus of intervertebral discs (NPs‐IVD), which may express neurogenic properties, may be implicated in IVD disease. NPs‐IVD isolated from 14 human pathological discs were cultured under mesenchymal and neural differentiation. An induction of the neural markers GFAP, NF, MAP2, O4, and a decrement of the expression of the immature neural markers β‐tubulin III, Nestin, NG2, occurred within the neural differentiation. The expression of TrkA and p75NGFR, the receptors of NGF, was not correlated with neural induction; in contrast, TrkB, the BDNF receptor, increased and was co‐expressed with acid sensing ion channel 3 (ASIC3). In the same condition, neuroinflammatory markers were over‐expressed. We confirm our hypothesis that stem cells within IVD degeneration acquire neurogenic phenotype, causing the induction of markers related to inflammatory condition. These cells could promote the enrolment of neurotrophines in adaptation to the acidic microenvironment in degenerative conditions. These data could improve our knowledge about IVD cellularity and eventually lead to the development of pharmacological therapies.

Modulation of Neuroinflammation in the Central Nervous System: Role of Chemokines and Sphingolipids

Neuroinflammation is a process involved in the pathogenesis of different disorders, both autoimmune, such as neuropsychiatric systemic lupus erythematosus, and degenerative, such as Alzheimer’s and Parkinson’s disease. In the central nervous system, the local milieu is tightly regulated by different mediators, among which are chemoattractant cytokines, also known as chemokines. These small molecules are able to modulate trafficking of immune cells in the course of nervous system development or in response to tissue damage, and different patterns of chemokine molecule and receptor expression have been described in several neuroinflammatory disorders. In recent years, a number of studies have highlighted a pivotal role of sphingolipids in regulating neuroinflammation. Sphingolipids have different functions, among which are the control of leukocyte egress from lymphonodes into inflamed tissues, the expression of various mediators of inflammation and a direct effect on the cells of the central nervous system as regulators of neuroinflammation. In the future, a better knowledge of these two groups of mediators could provide insight into the pathogenesis of neuroinflammatory disorders and could help develop novel diagnostic tools and therapeutic strategies.

Autocrine/Paracrine Sphingosine- 1-Phosphate Fuels Proliferative and Stemness Qualities of Glioblastoma Stem Cells

Accumulating reports suggest that human glioblastoma contains glioma stem‐like cells (GSCs) which act as key determinants driving tumor growth, angiogenesis, and contributing to therapeutic resistance. The proliferative signals involved in GSC proliferation and progression remain unclear. Using GSC lines derived from human glioblastoma specimens with different proliferative index and stemness marker expression, we assessed the hypothesis that sphingosine‐1‐phosphate (S1P) affects the proliferative and stemness properties of GSCs. The results of metabolic studies demonstrated that GSCs rapidly consume newly synthesized ceramide, and export S1P in the extracellular environment, both processes being enhanced in the cells exhibiting high proliferative index and stemness markers. Extracellular S1P levels reached nM concentrations in response to increased extracellular sphingosine. In addition, the presence of EGF and bFGF potentiated the constitutive capacity of GSCs to rapidly secrete newly synthesized S1P, suggesting that cooperation between S1P and these growth factors is of central importance in the maintenance and proliferation of GSCs. We also report for the first time that S1P is able to act as a proliferative and pro‐stemness autocrine factor for GSCs, promoting both their cell cycle progression and stemness phenotypic profile. These results suggest for the first time that the GSC population is critically modulated by microenvironmental S1P, this bioactive lipid acting as an autocrine signal to maintain a pro‐stemness environment and favoring GSC proliferation, survival and stem properties. GLIA 2014;62:1968–1981

The Adipose Mesenchymal Stem Cell Secretome Inhibits Inflammatory Responses of Microglia: Evidence for an Involvement of Sphingosine-1-Phosphate Signalling

Central nervous system (CNS) inflammation is primarily driven by microglial cells which secrete proinflammatory cytokines and undergo proliferation upon activation, as it occurs in neurodegenerative diseases. Uncontrolled or prolonged CNS inflammation is potentially harmful and can result in cellular damage. Recently, many studies have focused on human adipose tissue as an attractive source of cytokines with immunosuppressive properties that potentially modulate inflammation. Our study aimed to evaluate if different methods of human tissue collection could affect adipose mesenchymal stem cell (ADSC)-derived cytokine secretion and investigate the effects of ADSC secretome in modulating microglia activation and the possible implication of sphingosine-1-phosphate (S1P) in these effects. Our results demonstrate that the conditioned medium (CM) of ADSCs isolated by two different processing methods (lipoaspirate and Lipogems) significantly inhibited the lipopolysaccharide (LPS)-induced effects on microglia activation, including microglial expression of CD68, cytokine secretion, proliferation, and migration. Pulse studies with radiolabeled sphingosine demonstrated that LPS treatment of resting microglia induced a significant increase of both cellular and extracellular S1P. Moreover, and of relevance, FTY720, a functional antagonist of S1P receptor, inhibited the multiple LPS-induced proinflammatory effects on microglia, and S1P suppressed the anti-inflammatory effect of ADSC-CM. This suggests that LPS-mediated microglial activation is countered by ADSC-CM through the modulation of sphingosine kinase/S1P signalling.

Platelet-derived sphingosine-1-phosphate and inflammation: from basic mechanisms to clinical implications.

Abstract Beyond key functions in hemostasis and thrombosis, platelets are recognized as key players of inflammation, an underlying feature of a variety of diseases. In this regard, platelets act as a circulating source of several pro- and anti-inflammatory molecules, which are secreted from their intracellular stores upon activation. Among them, mounting evidence highlights a crucial role of sphingosine-1-phosphate (S1P), a multifunctional sphingoid mediator. S1P-induced pleiotropic effects include those crucial in inflammatory processes, such as the maintenance of the endothelial barrier integrity, and leukocyte activation and recruitment at the injured site. This review outlines the peculiar features and molecular mechanisms that allow platelets for acting as a unique factory that produces and stores S1P in large quantities. A particular emphasis is placed on the autocrine and paracrine roles of S1P derived from the “inflamed” platelets, highlighting the role of its cross-talk with endothelial and blood cells involved in inflammation, and the mechanisms of its contribution to the development and progression of inflammatory diseases. Finally, potential clinical implications of platelet-derived S1P as diagnostic tool of inflammatory severity, and as therapeutic target in inflammation are discussed.

Schilder's disease: non-invasive diagnosis? :A case report and review.

Schilder’s disease, or myelinoclastic diffuse sclerosis, is a rare disorder characterised by an inflammatory white matter plaque of demyelination. Clinical signs and symptoms might be atypical for early multiple sclerosis and at imaging the lesion is easily taken for a brain tumour. Regardless of the use of Poser’s criteria for clinical diagnosis of Schilder’s disease proposed in 1986, diagnostic difficulties are still present, as evidenced by the many reported cases in the English literature revised (Pubmed indexed, period 1998–2008). It clearly emerges that neuroradiological features, observable in additional magnetic resonance sequences are crucial, besides the consideration of Poser’s criteria, in differentiating between demyelinating lesions and brain tumours. A 29-year-old female patient is presented, where a careful evaluation of both the clinical and radiological features, which might have been at a first glance misleadingly suggestive for a brain tumour, allowed non-invasive diagnosis of Schilder’s disease.

Adjuvant Temozolomide Chemotherapy for Treatment of Papillary Tumor of the Pineal Region

BACKGROUND We present a personal case of papillary pineocytoma in a 42-year-old woman. METHODS The lesion was first treated surgically both for diagnostic aims and for resolution of the mass effect causing hydrocephalus and correlated neurological disturbances. Because the tumor recurred after surgery and radiotherapy, we decided to further treat the patient with chemotherapy, in particular with temozolomide. RESULTS Currently, almost 9 years after the first treatment, the patient is symptom-free and follow-up magnetic resonance imaging shows no tumor recurrence. CONCLUSION Although surgery should be considered the first-choice therapy, we think that temozolomide can be a valid option in case of recurrence of these rare tumors.