Effects of Selective α7 Nicotinic Acetylcholine Receptor Stimulation in In Vitro Oligodendrocytes and Putative Implication in Neuroinflammation

Background: Oligodendrocytes (OLs) are highly sensitive to oxygen-reactive species produced during neuro-inflammation. α7 nAChRs are expressed in glial cells where they can modulate several physiological and pathological functions. OL progenitors (OPCs) respond to cholinergic stimuli via muscarinic receptors that are mainly involved in the modulation of their proliferation. Differently, the role of nicotinic receptors, in particular α7 nAChRs, has been poorly investigated. In this study, we evaluated the expression of α7 nAChRs in a model of OPCs (Oli neu) and the potential effects mediated by their selective activation. Methods: The effects of α7 nAChRs stimulation on cell proliferation and survival were assessed by the MTT assay. RT-PCR and Western blot analysis were used to analyse the expression of α7 nAChRs and proliferative and differentiative markers (PCNA, MBP). The antioxidant and anti-inflammatory properties of α7 nAChRs were analysed evaluating NFR2 expression and ROS levels through DCFDA staining while Oil Red O staining was used for lipid content analysis. Results: The α7 nAChR is expressed both in OPCs and OLs and its stimulation by the selective agonist ICH3 increases cell proliferation without modifying the OLs differentiation capability. Moreover, ICH3 showed anti-inflammatory and antioxidant effects against LPS exposure. Conclusions: The results herein obtained confirm the role of α7 nAChR in the modulation of neuroinflammatory processes as well as their protective effects on OLs.