Investigation of effects of Brimonidine tartrate loaded LMSC cells on in vitro injury model of neuron cells

Brimonidine tartrate (BT), with a proven neuroprotective effect, is an eyedrop that lowers intraocular pressure by functioning as a selector alpha-2 adrenoreceptor agonist. Although it is frequently used in glaucoma, there is no information on its effects on limbal mesenchymal stem cells (LMSCs) which reside in the corneoscleral part of the eye and have important roles in the support of the corneal surface. BT is a promising agent with neuroprotective effectiveness in müller cells, retinal epithelium cells and retinal ganglion cells (RGCs). The aim of the study was to determine the effects of Brimonidine tartrate loaded LMSC cells on in vitro injury models of neuron cells. LMSCs were isolated from corneoscleral rims and tissue explants were cultured for 3 weeks in Matrigel-coated plates. After checking characterization and their differentiation abilities stem cells are stored in order to use in further experiments. The optimum BT dos was determined with CTG cell viability assay. The role of BT treatment in the regulation of LMSC proliferation via which cellular signaling mechanisms was determined by immunofluorescence staining of the Ki67, the scratch assay, ROS assay, and RT-q-PCR. Also, the effect of BT-loaded LMSC on H2O2 injured primary hippocampal cells was shown with the expression of inflammatory genes upon co-culture experiments. BT and LMSC can be used for therapeutic purposes for the optic nerve injury, glaucoma model, and RGCs degeneration through their neuroprotective potentials. From this point of view, we hypothesized that intravitreally injection of Brimonidine tartrate-loaded limbal mesenchymal stem cells might be used as a protectant against cell death during recovery of retinal disorders Keywords: brimonidine tartrate, limbal mesenchymal stem cell, primary hippocampal cell, co-culture