Jin Zhu1, Chen Qu, Xiang Lu, Shu Zhang. 1. Clinical Research Center, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, P. R. China.
Abstract
BACKGROUND: Activated microglia perform many of the immune effector functions typically associated with macrophages. However, the regulators involved in microglial activation are not well defined. Because microglia play a pivotal role in immune surveillance of the CNS, we studied the effect of the neuromediators histamine and substance P on microglia. METHODS: The induction of microglial activation by histamine and substance P was examined using primary cultured microglia. Fluorescent images were acquired with a confocal microscope. The levels of TNF-α and IL-6 were measured with a commercial ELISA kit. Intracellular reactive oxygen species (ROS) levels were determined by dichlorodihydrofluorescein oxidation. The mitochondrial membrane potential was assessed with the MitoProbe™ JC-1 assay kit. RESULTS: We found that the neuromediators histamine and substance P were able to stimulate microglial activation and the subsequent production of ROS and proinflammatory factors TNF-α and IL-6. These effects were partially abolished by antagonists of the histamine receptors H1 and H4 and of the substance P receptors NK-1, NK-2 and NK-3. Histamine induced mitochondrial membrane depolarization in microglia. CONCLUSIONS: These results indicate that the neuromediators histamine and SP can trigger microglial activation and release of pro-inflammatory factors from microglia, thus contributing to the development of microglia-mediated inflammation in the brain.
BACKGROUND: Activated microglia perform many of the immune effector functions typically associated with macrophages. However, the regulators involved in microglial activation are not well defined. Because microglia play a pivotal role in immune surveillance of the CNS, we studied the effect of the neuromediators histamine and substance P on microglia. METHODS: The induction of microglial activation by histamine and substance P was examined using primary cultured microglia. Fluorescent images were acquired with a confocal microscope. The levels of TNF-α and IL-6 were measured with a commercial ELISA kit. Intracellular reactive oxygen species (ROS) levels were determined by dichlorodihydrofluorescein oxidation. The mitochondrial membrane potential was assessed with the MitoProbe™ JC-1 assay kit. RESULTS: We found that the neuromediators histamine and substance P were able to stimulate microglial activation and the subsequent production of ROS and proinflammatory factors TNF-α and IL-6. These effects were partially abolished by antagonists of the histamine receptors H1 and H4 and of the substance P receptors NK-1, NK-2 and NK-3. Histamine induced mitochondrial membrane depolarization in microglia. CONCLUSIONS: These results indicate that the neuromediators histamine and SP can trigger microglial activation and release of pro-inflammatory factors from microglia, thus contributing to the development of microglia-mediated inflammation in the brain.
Authors: Colin Casault; Abdulaziz S Al Sultan; Mohammad Banoei; Philippe Couillard; Andreas Kramer; Brent W Winston Journal: Neurocrit Care Date: 2019-02 Impact factor: 3.210
Authors: Ranjana Patnaik; Aruna Sharma; Stephen D Skaper; Dafin F Muresanu; José Vicente Lafuente; Rudy J Castellani; Ala Nozari; Hari S Sharma Journal: Mol Neurobiol Date: 2018-01 Impact factor: 5.590