FAK/Src family of kinases: protective or aggravating factor for ischemia reperfusion injury in nervous system?

MiR-15p-5p Mediates the Coordination of ICAM-1 and FAK to Promote Endothelial Cell Proliferation and Migration

Intercellular adhesion molecule-1 (ICAM-1) in endothelial cells is critical for neutrophil adhesion and transmigration across the endothelium. Focal adhesion kinase (FAK), which controls the turnover of focal adhesion to regulate cell adhesion and migration, plays a role in the resolution of inflammation. However, the coordinated involvement of ICAM-1 and FAK during endothelial inflammation has yet to be elucidated. This study reports that, as part of an inflammatory response, ICAM-1 controls FAK expression in endothelial cells via the microRNA miR-15b-5p. Induction of lung injury by lipopolysaccharide (LPS) resulted in higher levels of FAK expression in inflammatory tissues, while in ICAM-1 knockout mice, FAK expression was reduced in the lungs. FAK expression was also reduced in endothelial cells following ICAM-1 siRNA downregulation. Furthermore, ICAM-1 inhibited miR-15b-5p expression while increasing FAK mRNA and protein expression via binding of miR-15b-5p to the 3' untranslated region (UTR) of FAK. ICAM-1 inhibited miR-15b-5p promoter activity and hence reduced miR-15b-5p expression. FAK increased endothelial cell proliferation and migration, whereas miR-15b-5p inhibited cell proliferation and migration. These findings indicate that the inflammatory molecule ICAM-1 regulates FAK expression via miR-15b-5p levels, which in turn controls endothelial cell proliferation and migration.

The role of non-receptor protein tyrosine kinases in the excitotoxicity induced by the overactivation of NMDA receptors

Protein tyrosine phosphorylation is one of the primary modes of regulation of N-methyl-d-aspartate (NMDA) receptors. The non-receptor tyrosine kinases are one of the two types of protein tyrosine kinases that are involved in this process. The overactivation of NMDA receptors is a primary reason for neuron death following cerebral ischemia. Many studies have illustrated the important role of non-receptor tyrosine kinases in ischemia insults. This review introduces the roles of Src, Fyn, focal adhesion kinase, and proline-rich tyrosine kinase 2 in the excitotoxicity induced by the overactivation of NMDA receptors following cerebral ischemia.

The effect of endocannabinoid system in ischemia-reperfusion injury: a friend or a foe?

INTRODUCTION

In recent years, the endocannabinoid system has emerged as a new therapeutic target in variety of disorders associated with inflammation and tissue injury, including those of the neuronal, liver, renal and cardiovascular system. The aim of the present review is to elucidate the effect of endocannabinoid system on ischemia reperfusion injury (IRI) in different organs and systems.

AREAS COVERED

The MEDLINE/PubMed database was searched for publications with the medical subject heading Cannabinoids* (CBs), CB receptors*, organ*, ischemia/reperfusion injury*, endocannabinoid* and system*. The initial relevant studies retrieved from the literature were 91 from PubMed. This number was initially limited to 35, after excluding the reviews and studies reporting data for receptors other than cannabinoid.

EXPERT OPINION

CB2 receptors may play an important compensatory role in controlling tissue inflammation and injury in cells of the neuronal, cardiovascular, liver and renal systems, as well as in infiltrating monocytes/macrophages and leukocytes during various pathological conditions of the systems (atherosclerosis, restenosis, stroke, myocardial infarction, heart, liver and renal failure). These receptors limit inflammation and associated tissue injury. On the basis of preclinical results, pharmacological modulation of CB2 receptors may hold a unique therapeutic potential in stroke, myocardial infarction, atherosclerosis, IRI and liver disease.