Ran Barzilay

Suicide prevention strategies revisited: 10-year systematic review.

BACKGROUND Many countries are developing suicide prevention strategies for which up-to-date, high-quality evidence is required. We present updated evidence for the effectiveness of suicide prevention interventions since 2005. METHODS We searched PubMed and the Cochrane Library using multiple terms related to suicide prevention for studies published between Jan 1, 2005, and Dec 31, 2014. We assessed seven interventions: public and physician education, media strategies, screening, restricting access to suicide means, treatments, and internet or hotline support. Data were extracted on primary outcomes of interest, namely suicidal behaviour (suicide, attempt, or ideation), and intermediate or secondary outcomes (treatment-seeking, identification of at-risk individuals, antidepressant prescription or use rates, or referrals). 18 suicide prevention experts from 13 European countries reviewed all articles and rated the strength of evidence using the Oxford criteria. Because the heterogeneity of populations and methodology did not permit formal meta-analysis, we present a narrative analysis. FINDINGS We identified 1797 studies, including 23 systematic reviews, 12 meta-analyses, 40 randomised controlled trials (RCTs), 67 cohort trials, and 22 ecological or population-based investigations. Evidence for restricting access to lethal means in prevention of suicide has strengthened since 2005, especially with regard to control of analgesics (overall decrease of 43% since 2005) and hot-spots for suicide by jumping (reduction of 86% since 2005, 79% to 91%). School-based awareness programmes have been shown to reduce suicide attempts (odds ratio [OR] 0·45, 95% CI 0·24-0·85; p=0·014) and suicidal ideation (0·5, 0·27-0·92; p=0·025). The anti-suicidal effects of clozapine and lithium have been substantiated, but might be less specific than previously thought. Effective pharmacological and psychological treatments of depression are important in prevention. Insufficient evidence exists to assess the possible benefits for suicide prevention of screening in primary care, in general public education and media guidelines. Other approaches that need further investigation include gatekeeper training, education of physicians, and internet and helpline support. The paucity of RCTs is a major limitation in the evaluation of preventive interventions. INTERPRETATION In the quest for effective suicide prevention initiatives, no single strategy clearly stands above the others. Combinations of evidence-based strategies at the individual level and the population level should be assessed with robust research designs. FUNDING The Expert Platform on Mental Health, Focus on Depression, and the European College of Neuropsychopharmacology.

Regenerative effect of neural-induced human mesenchymal stromal cells in rat models of Parkinson's disease

BACKGROUND Human bone marrow multipotent mesenchymal stromal cells (hMSC), because of their capacity of multipotency, may provide an unlimited cell source for cell replacement therapy. The purpose of this study was to assess the developmental potential of hMSC to replace the midbrain dopamine neurons selectively lost in Parkinsons disease. METHODS Cells were isolated and characterized, then induced to differentiate toward the neural lineage. In vitro analysis of neural differentiation was achieved using various methods to evaluate the expression of neural and dopaminergic genes and proteins. Neural-induced cells were then transplanted into the striata of hemi-Parkinsonian rats; animals were tested for rotational behavior and, after killing, immunohistochemistry was performed. RESULTS Following differentiation, cells displayed neuronal morphology and were found to express neural genes and proteins. Furthermore, some of the cells exhibited gene and protein profiles typical of dopaminergic precursors. Finally, transplantation of neural-induced cells into the striatum of hemi-Parkinsonian rats resulted in improvement of their behavioral deficits, as determined by apomorphine-induced rotational behavior. The transplanted induced cells proved to be of superior benefit compared with the transplantation of naive hMSC. Immunohistochemical analysis of grafted brains revealed that abundant induced cells survived the grafts and some displayed dopaminergic traits. DISCUSSION Our results demonstrate that induced neural hMSC may serve as a new cell source for the treatment of neurodegenerative diseases and have potential for broad application. These results encourage further developments of the possible use of hMSC in the treatment of Parkinsons disease.

Introducing Transcription Factors to Multipotent Mesenchymal Stem Cells: Making Transdifferentiation Possible

Multipotent mesenchymal stem cells (MSCs) represent a promising autologous source for regenerative medicine. Because MSCs can be isolated from adult tissues, they represent an attractive cell source for autologous transplantation. A straightforward therapeutic strategy in the field of stem cell‐based regenerative medicine is the transplantation of functional differentiated cells as cell replacement for the lost or defective cells affected by disease. However, this strategy requires the capacity to regulate stem cell differentiation toward the desired cell fate. This therapeutic approach assumes the capability to direct MSC differentiation toward diverse cell fates, including those outside the mesenchymal lineage, a process termed transdifferentiation. The capacity of MSCs to undergo functional transdifferentiation has been questioned over the years. Nonetheless, recent studies support that genetic manipulation can serve to promote transdifferentiation. Specifically, forced expression of certain transcription factors can lead to reprogramming and alter cell fate. Using such a method, fully differentiated lymphocytes have been reprogrammed to become macrophages and, remarkably, somatic cells have been reprogrammed to become embryonic stem‐like cells. In this review, we discuss the past and current research aimed at transdifferentiating MSCs, a process with applications that could revolutionize regenerative medicine. STEM CELLS 2009;27:2509–2515

Induction of Human Mesenchymal Stem Cells into Dopamine-Producing Cells with Different Differentiation Protocols

Several reports have shown that human mesenchymal stem cells (MSCs) are capable of differentiating outside the mesenchymal lineage. We sought to induce MSCs to differentiate into dopamine-producing cells for potential use in autologous transplantation in patients with Parkinsons disease (PD). Following cell culture with various combinations of differentiation agents under serum-free defined conditions, different levels of up-regulation were observed in the protein expression of tyrosine hydroxylase, the rate-limiting enzyme in dopamine synthesis. Further analysis of selected differentiation protocols revealed that the induced cells displayed a neuron-like morphology and expressed markers suggesting neuronal differentiation. In addition, there was an increase in Nurr 1, the dopaminergic transcription factor gene, concomitant with a decrease gamma-aminobutyric acid (GABA)ergic marker expression, suggesting a specific dopaminergic direction. Moreover, the induced cells secreted dopamine in response to depolarization. These results demonstrate the great therapeutic potential of human MSCs in PD.

Migration of Neurotrophic Factors‐Secreting Mesenchymal Stem Cells Toward a Quinolinic Acid Lesion as Viewed by Magnetic Resonance Imaging

Stem cell‐based treatment is a promising frontier for neurodegenerative diseases. We propose a novel protocol for inducing the differentiation of rat mesenchymal stem cells (MSCs) toward neurotrophic factor (NTF)‐secreting cells as a possible neuroprotective agent. One of the major caveats of stem cell transplantation is their fate post‐transplantation. To test the viability of the cells, we tracked the transplanted cells in vivo by magnetic resonance imaging (MRI) scans and validated the results by histology. MSCs went through a two‐step medium‐based differentiation protocol, followed by in vitro characterization using immunocytochemistry and immunoblotting analysis of the cell media. We examined the migratory properties of the cells in the quinolinic acid (QA)‐induced striatal lesion model for Huntingtons disease. The induced cells were labeled and transplanted posterior to the lesion. Rats underwent serial MRI scans to detect cell migration in vivo. On the 19th day, animals were sacrificed, and their brains were removed for immunostaining. Rat MSCs postinduction exhibited both neuronal and astrocyte markers, as well as production and secretion of NTFs. High‐resolution two‐dimensional and three‐dimensional magnetic resonance images revealed that the cells migrated along a distinct route toward the lesion. The in vivo MRI results were validated by the histological study, which demonstrated that phagocytosis had only partially occurred and that MRI could correctly depict the status of the migrating cells. The results show that these cells migrated toward a QA lesion and therefore survived for 19 days post‐transplantation. This gives hope for future research harnessing these cells for treating neurodegenerative diseases.

Mesenchymal stem cells induced to secrete neurotrophic factors attenuate quinolinic acid toxicity: A potential therapy for Huntington's disease

Huntingtons disease (HD) is a hereditary, progressive and ultimately fatal neurodegenerative disorder. Excitotoxicity and reduced availability of neurotrophic factors (NTFs) likely play roles in HD pathogenesis. Recently we developed a protocol that induces adult human bone marrow derived mesenchymal stem cells (MSCs) into becoming NTF secreting cells (NTF(+) cells). Striatal transplantation of such cells represents a promising autologous therapeutic approach whereby NTFs are delivered to damaged areas. Here, the efficacy of NTF(+) cells was evaluated using the quinolinic acid (QA) rat model for excitotoxicity. We show that NTF(+) cells transplanted into rat brains after QA injection survive transplantation (19% after 6 weeks), maintain their NTF secreting phenotype and significantly reduce striatal volume changes associated with QA lesions. Moreover, QA-injected rats treated with NTF(+) cells exhibit improved behavior; namely, perform 80% fewer apomorphine induced rotations than PBS-treated QA-injected rats. Importantly, we found that MSCs derived from HD patients can be induced to become NTF(+) cells and exert efficacious effects similarly to NTF(+) cells derived from healthy donors. To our knowledge, this is the first study to take adult bone marrow derived mesenchymal stem cells from patients with an inherited disease, transplant them into an animal model and evidence therapeutic benefit. Using MRI we demonstrate in vivo that PBS-treated QA-injected striatae exhibit increasing T(2) values over time in lesioned regions, whereas T(2) values decrease in equivalent regions of QA-injected rats treated with NTF(+) cells. We conclude that NTF cellular treatment could serve as a novel therapy for managing HD.

Comparative characterization of bone marrow-derived mesenchymal stromal cells from four different rat strains

BACKGROUND AIMS Bone marrow (BM) multipotent mesenchymal stromal cells (MSC) hold great potential for cell-based regenerative medicine. Because of the growing use of autologous rat MSC transplantation in various rat models, there is a need to establish minimal criteria for rat MSC characterization independent of the specific strain employed in each study. We aimed to compare the phenotypic and functional traits of BM MSC from the four strains of rats commonly used in research: Fisher, Lewis, Sprague-Dawley and Wistar. METHODS Rat MSC were isolated from the BM of the four different rat strains in an identical fashion. Cells were characterized for their cell-surface phenotype in early and late passage. Functional mesenchymal differentiation capacities were examined following adipogenic and osteogenic inductions. Population doubling times were determined across the four strains throughout 10 passages. In vitro proliferation assays of immune cells were conducted following co-culture of spleen cells and MSC of the four different strains. RESULTS We found that rat MSC from different strains exhibited similar cell-surface phenotype. Expansion rates and differentiation capacities of the MSC were also similar across the different strains. Co-culture of rat MSC with spleen cells obtained from rats of a different strain did not induce proliferation of immune cells. CONCLUSIONS Our findings suggest that BM-derived MSC from different strains share similar characteristics, in contrast to the variations previously described in the characterization of mice MSC from different strains.

Placental mesenchymal stromal cells induced into neurotrophic factor-producing cells protect neuronal cells from hypoxia and oxidative stress.

BACKGROUND AIMS Mesenchymal stromal cells (MSC) may be useful in a range of clinical applications. The placenta has been suggested as an abundant, ethically acceptable, less immunogenic and easily accessible source of MSC. The aim of this study was to evaluate the capacity of induced placental MSC to differentiate into neurotrophic factor-producing cells (NTF) and their protective effect on neuronal cells. METHODS MSC were isolated from placentas and characterized by fluorescence-activated cell sorting (FACS). The cells underwent an induction protocol to differentiate them into NTF. Analysis of the cellular differentiation was done using polymerase chain reactions (PCR), immunocytochemical staining and enzyme-linked immunosorbent assays (ELISA). Conditioned media from placental MSC (PL-MSC) and differentiated MSC (PL-DIFF) were collected and examined for their ability to protect neural cells. RESULTS The immunocytochemical studies showed that the cells displayed typical MSC membrane markers. The cells differentiated into osteoblasts and adipocytes. PCR and immunohistology staining demonstrated that the induced cells expressed typical astrocytes markers and neurotrophic factors. Vascular endothelial growth factor (VEGF) levels were higher in the conditioned media from PL-DIFF compared with PL-MSC, as indicated by ELISA. Both PL-DIFF and PL-MSC conditioned media markedly protected neural cells from oxidative stress induced by H(2)O(2) and 6-hydroxydopamine. PL-DIFF conditioned medium had a superior effect on neuronal cell survival. Anti-VEGF antibodies (Bevacizumab) reduced the protective effect of the conditioned media from differentiated and undifferentiated MSC. CONCLUSIONS This study has demonstrated a neuroprotective effect of MSC of placental origin subjected to an induction differentiation protocol. These data offer the prospect of using placenta as a source for stem cell-based therapies.

Intracerebral adult stem cells transplantation increases brain-derived neurotrophic factor levels and protects against phencyclidine-induced social deficit in mice

Stem cell-based regenerative therapy is considered a promising cellular therapeutic approach for the patients with incurable brain diseases. Mesenchymal stem cells (MSCs) represent an attractive cell source for regenerative medicine strategies for the treatment of the diseased brain. Previous studies have shown that these cells improve behavioral deficits in animal models of neurological disorders such as Parkinsons and Huntingtons diseases. In the current study, we examined the capability of intracerebral human MSCs transplantation (medial pre-frontal cortex) to prevent the social impairment displayed by mice after withdrawal from daily phencyclidine (PCP) administration (10 mg kg−1 daily for 14 days). Our results show that MSCs transplantation significantly prevented the PCP-induced social deficit, as assessed by the social preference test. In contrast, the PCP-induced social impairment was not modified by daily clozapine treatment. Tissue analysis revealed that the human MSCs survived in the mouse brain throughout the course of the experiment (23 days). Significantly increased cortical brain-derived neurotrophic factor levels were observed in the MSCs-treated group as compared with sham-operated controls. Furthermore, western blot analysis revealed that the ratio of phosphorylated Akt to Akt was significantly elevated in the MSCs-treated mice compared with the sham controls. Our results demonstrate that intracerebral transplantation of MSCs is beneficial in attenuating the social deficits induced by sub-chronic PCP administration. We suggest a novel therapeutic approach for the treatment of schizophrenia-like negative symptoms in animal models of the disorder.

Mesenchymal Stem Cell Transplantation Promotes Neurogenesis and Ameliorates Autism Related Behaviors in BTBR Mice

Autism spectrum disorders (ASD) are characterized by social communication deficits, cognitive rigidity, and repetitive stereotyped behaviors. Mesenchymal stem cells (MSC) have a paracrine regenerative effect, and were speculated to be a potential therapy for ASD. The BTBR inbred mouse strain is a commonly used model of ASD as it demonstrates robust behavioral deficits consistent with the diagnostic criteria for ASD. BTBR mice also exhibit decreased brain‐derived neurotrophic factor (BDNF) signaling and reduced hippocampal neurogenesis. In the current study, we evaluated the behavioral and molecular effects of intracerebroventricular MSC transplantation in BTBR mice. Transplantation of MSC resulted in a reduction of stereotypical behaviors, a decrease in cognitive rigidity and an improvement in social behavior. Tissue analysis revealed elevated BDNF protein levels in the hippocampus accompanied by increased hippocampal neurogenesis in the MSC‐transplanted mice compared with sham treated mice. This might indicate a possible mechanism underpinning the behavioral improvement. Our study suggests a novel therapeutic approach which may be translatable to ASD patients in the future. Autism Res 2015.