Key differences between olfactory ensheathing cells and Schwann cells regarding phagocytosis of necrotic cells: implications for transplantation therapies
SCIENTIFIC REPORTS
Authors: Nazareth, L.; Shelper, T. B.; Chacko, A.; Basu, S.; Delbaz, A.; Lee, J. Y. P.; Chen, M.; St John, J. A.; Ekberg, J. A. K.
Abstract
Transplantation of peripheral nervous system glia is being explored for treating neural injuries, in particular central nervous system injuries. These glia, olfactory ensheathing cells (OECs) and Schwann cells (SCs), are thought to aid regeneration by clearing necrotic cells, (necrotic bodies, NBs), as well as myelin debris. The mechanism by which the glia phagocytose and traffic NBs are not understood. Here, we show that OECs and SCs recognize phosphatidylserine on NBs, followed by engulfment and trafficking to endosomes and lysosomes. We also showed that both glia can phagocytose and process myelin debris. We compared the time-course of glial phagocytosis (of both NBs and myelin) to that of macrophages. Internalization and trafficking were considerably slower in glia than in macrophages, and OECs were more efficient phagocytes than SCs. The two glial types also differed regarding their cytokine responses after NB challenge. SCs produced low amounts of the pro-inflammatory cytokine TNF-alpha while OECs did not produce detectable TNF-alpha. Thus, OECs have a higher capacity than SCs for phagocytosis and trafficking, whilst producing lower amounts of pro-inflammatory cytokines. These findings suggest that OEC transplantation into the injured nervous system may lead to better outcomes than SC transplantation.
Metabolomics Analysis of the Effect of Hydrogen-Rich Water on Myocardial Ischemia-Reperfusion Injury in Rats
JOURNAL OF BIOENERGETICS AND BIOMEMBRANES
Authors: Li, Liangtong; Liu, Tongtong; Liu, Li; Zhang, Zhe; Li, Shaochun; Zhang, Zhiling; Zhou, Yujuan; Liu, Fulin
Abstract
To investigate the effect of hydrogen-rich water on myocardial tissue metabolism in a myocardial ischemia-reperfusion injury (MIRI) rat model. Twelve rats were randomly divided into a hydrogen-rich water group and a control group of size 6 each. After the heart was removed, it was fixed in the Langendorff device, and the heart was perfused with 37 degrees C perfusion solution pre-balanced with oxygen. The control group was perfused with Kreb's-Ringers (K-R) solution, and the hydrogen-rich water group was perfused with K-R solution + hydrogen-rich water. Liquid Chromatograph Mass Spectrometer (LC-MS) analysis platform was used for metabolomics research. Principle component analysis (PCA), partial least squares discriminant analysis (PLS-DA), orthogonal partial least squares discriminant analysis (OPLS-DA), Variable importance in projection (VIP) value of OPLS-DA model (threshold value >= 1) were employed with independent sample T Test (p < 0.05) to find differentially expressed metabolites, and screen for differential metabolic pathways. VIP (OPLS-DA) analysis was performed with T test, and the metabolites of the control group and the hydrogen-rich water group were significantly different, and the glycerophospholipid metabolism was screened. Seven myocardial ischemia-reperfusion injury (MIRI)-related signaling pathways were identified, including glycerophospholipid metabolism, glycosylphosphatidylinositol (GPI) anchored biosynthesis, and purine metabolism, as well as 10 biomarkers such as phosphatidylcholine, phosphatidylethanolamine and phosphatidylserine. Hydrogen-rich water regulates the metabolic imbalance that could change MIRI myocardial tissue metabolism, and alleviate ischemia-reperfusion injury in isolated hearts of rats through multiple signaling pathways.