miRNA-544a Regulates the Inflammation of Spinal Cord Injury by Inhibiting the Expression of NEUROD4
CELLULAR PHYSIOLOGY AND BIOCHEMISTRY
Authors: Yang, Lei; Ge, Dawei; Chen, Xi; Jiang, Chunzhi; Zheng, Shengnai
Abstract
Background/Aims: To explore the potential role of miR-544a in spinal cord injury and the possible mechanism involved. Methods: We established a mouse model with spinal cord injury to examine the changes in grip force recovery of the forelimb or the posterior limb of the mouse. Microarray was performed to achieve differentiated miRNAs in the mice. The expressions of miR-544a, MCP-1, IL36B and IL17B after spinal cord injury were detected by qRT-PCR. Subsequently, miR-544a was overexpressed to observe changes in inflammation and grip strength after spinal cord injury. Target gene of miR-544a was then predicted using bioinformatics technology. Finally, dual luciferase reporter gene assay was used to verify the binding of miR-544a to its target gene. Results: Using mice models with spinal cord injury, we found that the strength of their four limbs began to recover 7 days after injury. The results of microarray and qRT-PCR confirmed that mir-544a level in mice with spinal cord injury decreased with increase of injury time, while the levels of inflammatory genes MCP-1 (monocyte chemoattractant protein-1), IL1 (interleukin-1) and TNF-alpha (tumor necrosis factor alpha) IL36B (interleukin-36 beta) and IL17B (interleukin-17 beta) were significantly increased. However, overexpression of miR-544a in the mice significantly reduced the level of inflammation and restored their grip strength in their four limbs. Finally, we found that miR-544a can bind to the NEUROD4 (Neurogenic differentiation 4) 3'UTR (Untranslated Region) region through bioinformatics website prediction, which was further confirmed by dual luciferase reporter assay. NEUROD4 level was significantly reduced following the overexpression of miR-544a. Conclusion: The expression of miR-544a was significantly decreased after spinal cord injury. High expression of miR-544a could alleviate the inflammation caused by spinal cord injury and promote the recovery of spinal cord via the inhibition of NEUROD4. (C) 2018 The Author(s) Published by S. Karger AG, Basel.
Cyto/chemokine profile of in vitro scratched keratinocyte model: Implications of significant upregulation of CCL20, CXCL8 and IL36G in Koebner phenomenon
JOURNAL OF DERMATOLOGICAL SCIENCE
Authors: Furue, Kazuhisa; Ito, Takamichi; Tanaka, Yuka; Yumine, Ayako; Hashimoto-Hachiya, Akiko; Takemura, Masaki; Murata, Maho; Yamamura, Kazuhiko; Tsuji, Gaku; Furue, Masutaka
Abstract
Background: Scratch injury induces Koebner phenomenon in psoriasis. Smoking is also a risk factor for psoriasis. Keratinocytes can produce various psoriasis-related molecules including TNF, IL1A, IL1B, 1L6, IL12B, ILI7C, IL23 A, IL36 A, IL36B, IL36G, CXCL1, CXCL2, CXCL8, CXCL9, CXCL10, CCL20, IFNB, and CAMP. However, the scratch-induced molecular profiling remains elusive. Objective: To profile the induction pattern of above-mentioned psoriasis-related and keratinocyte-derived molecules by scratch injury in the presence or absence of anti-psoriatic drugs or benzo[a]pyrene, a major environmental pollutant of tobacco smoke. Methods: Confluent normal human keratinocytes were scratched and molecules were assayed by qRT-PCR, ELISA and Western blotting with or without drugs and benzo[a]pyrene. Results: Among the 18 molecules, the scratch injury on a confluent keratinocyte sheet significantly and selectively upregulated the mRNA expression of four cyto/chemokines, CXCL8, CCL20, IL36G, and TNF, in a scratch-line-number-dependent manner under either low- or high-calcium condition. However, significant protein secretion was only demonstrated for CXCL8 and CCL20. The IL36 G protein was not secreted, but its intracellular level was significantly upregulated by scratch injury, whereas neither the secretion nor the intracellular level of TNF protein was affected by scratch injury. Dexamethasone, but not maxacalcitol nor the phosphodiesterase 4 inhibitor apremilast, partially inhibited the CXCL8 and CCL20 secretion. Benzo[a]pyrene significantly and synergistically enhanced the scratch-induced CCL20 secretion that may explain why smoking is a risk factor for psoriasis. Conclusion: CCL20 and to a less extent CXCL8 may play a key role in triggering the Koebner phenomenon after scratch injury to keratinocytes. (C) 2019 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.