Adipose tissue-derived stromal cells (ADSC) express oligodendrocyte and myelin markers, but they do not function as oligodendrocytes

Oligodendroglia Generated From Adult Rat Adipose Tissue by Direct Cell Conversion

Obtaining oligodendroglial cells from dispensable tissues would be of great interest for autologous or immunocompatible cell replacement therapy in demyelinating diseases, as well as for studying myelin-related pathologies or testing therapeutic approaches in culture. We evaluated the feasibility of generating oligodendrocyte precursor cells (OPCs) from adult rat adipose tissue by expressing genes encoding transcription factors involved in oligodendroglial development. Adipose-derived mesenchymal cells were lentivirally transduced with tetracycline-inducible Sox10, Olig2, Zfp536, and/or Nkx6.1 transgenes. Immunostaining with the OPC-specific O4 monoclonal antibody was used to mark oligodendroglial induction. O4- and myelin-associated glycoprotein (MAG)-positive cells emerged after 3 weeks when using the Sox10 + Olig2 + Zfp536 combination, followed in the ensuing weeks by GFAP-, O1 antigen-, p75NTR (low-affinity NGF receptor)-, and myelin proteins-positive cells. The O4⁺ cell population progressively expanded, eventually constituting more than 70% of cells in culture by 5 months. Sox10 transgene expression was essential for generating O4⁺ cells but was insufficient for inducing a full oligodendroglial phenotype. Converted cells required continuous transgene expression to maintain their glial phenotype. Some vestigial characteristics of mesenchymal cells were maintained after conversion. Growth factor withdrawal and triiodothyronine (T₃) supplementation generated mature oligodendroglial phenotypes, while FBS supplementation produced GFAP⁺- and p75NTR⁺-rich cultures. Converted cells also showed functional characteristics of neural-derived OPCs, such as the expression of AMPA, NMDA, kainate, and dopaminergic receptors, as well as similar metabolic responses to differentiation-inducing drugs. When co-cultured with rat dorsal root ganglion neurons, the converted cells differentiated and ensheathed multiple axons. We propose that functional oligodendroglia can be efficiently generated from adult rat mesenchymal cells by direct phenotypic conversion.

Injectable PLGA-Coated Ropivacaine Produces A Long-Lasting Analgesic Effect on Incisional Pain and Neuropathic Pain

The management of persistent postsurgical pain and neuropathic pain remains a challenge in the clinic. Local anesthetics have been widely used as simple and effective treatment for these 2 disorders, but the duration of their analgesic effect is short. We here reported a new poly lactic-co-glycolic acid (PLGA)-coated ropivacaine that was continuously released in vitro for at least 6 days. Perisciatic nerve injection of the PLGA-coated ropivacaine attenuated paw incision-induced mechanical allodynia and heat hyperalgesia during the incisional pain period, and spared nerve injury-induced mechanical and cold allodynia for at least 7 days postinjection. This effect was dose-dependent. Perisciatic nerve injection of the PLGA-coated ropivacaine did not produce detectable inflammation, tissue irritation, or damage in the sciatic nerve and surrounding muscles at the injected site, dorsal root ganglion, spinal cord, or brain cortex, although the scores for grasping reflex were mildly and transiently reduced in the higher dosage-treated groups. PERSPECTIVE: Given that PLGA is an FDA-approved medical material, and that ropivacaine is used currently in clinical practice, the injectable PLGA-coated ropivacaine represents a new and highly promising avenue in the management of postsurgical pain and neuropathic pain.

Mesenchymal stem cells and the neuronal microenvironment in the area of spinal cord injury

Cell-based technologies are used as a therapeutic strategy in spinal cord injury (SCI). Mesenchymal stem cells (MSCs), which secrete various neurotrophic factors and cytokines, have immunomodulatory, anti-apoptotic and anti-inflammatory effects, modulate reactivity/phenotype of astrocytes and the microglia, thereby promoting neuroregeneration seem to be the most promising. The therapeutic effect of MSCs is due to a paracrine mechanism of their action, therefore the survival of MSCs and their secretory phenotype is of particular importance. Nevertheless, these data are not always reported in efficacy studies of MSC therapy in SCI. Here, we provide a review with summaries of preclinical trials data evaluating the efficacy of MSCs in animal models of SCI. Based on the data collected, we have tried (1) to establish the behavior of MSCs after transplantation in SCI with an evaluation of cell survival, migration potential, distribution in the area of injured and intact tissue and possible differentiation; (2) to determine the effects MSCs on neuronal microenvironment and correlate them with the efficacy of functional recovery in SCI; (3) to ascertain the conditions under which MSCs demonstrate their best survival and greatest efficacy.

Calcium: A novel and efficient inducer of differentiation of adipose-derived stem cells into neuron-like cells

This study comparatively investigated the effectiveness of calcium and other well-known inducers such as isobutylmethylxanthine (IBMX) and insulin in differentiating human adipose-derived stem cells (ADSCs) into neuronal-like cells. ADSCs were immunophenotyped and differentiated into neuron-like cells with different combinations of calcium, IBMX, and insulin. Calcium mobilization across the membrane was determined. Differentiated cells were characterized by cell cycle profiling, staining of Nissl bodies, detecting the gene expression level of markers such as neuronal nuclear antigen (NeuN), microtubule associated protein 2 (MAP2), neuron-specific enolase (NSE), doublecortin, synapsin I, glial fibrillary acidic protein (GFAP), and myelin basic protein (MBP) by quantitative real-time polymerase chain reaction (quantitative real-time polymerase chain reaction (qRT-PCR) and protein level by the immunofluorescence technique. Treatment with Ca + IBMX + Ins induced neuronal appearance and projection of neurite-like processes in the cells, accompanied with inhibition of proliferation and halt in the cell cycle. A significantly higher expression of MBP, GFAP, NeuN, NSE, synapsin 1, doublecortin, and MAP2 was detected in differentiated cells, confirming the advantages of Ca + IBMX + Ins to the other combinations of inducers. Here, we showed an efficient protocol for neuronal differentiation of ADSCs, and calcium fostered differentiation by augmenting the number of neuron-like cells and instantaneous increase in the expression of neuronal markers.