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Diabetes patients often suffer chronic vascular complications resulting from endothelial dysfunction, smooth muscle cell (SMC) proliferation, inflammation and disturbed oxidative balance. Empagliflozin is one of three approved sodium-glucose cotransporter 2 (SGLT2) inhibitors for type 2 diabetes mellitus. was to determine the protective and repairing effect of EMPA in a model of vascular endothelial and SMC damage with 25-hydroxycholesterol (25-OHC). Human umbilical vascular endothelial cells (HUVECs) and SMCs were treated with compounds which induce DNA single-strand breaks (SSBs) and subjected to comet assay. Oxidative DNA damage was detected using endonuclease III (Nth) or human 8 oxoguanine DNA glycosylase (hOOG1). Reactive oxygen species (ROS) formation was determined by the fluorescence of a 6-carboxy-2′,7′-dichlorodihydrofluoresce probe in diacetate (H 2 DCFDA). 25-OHC-stimulated SMCs showed greater resistance to ROS generation and DNA damage compared to HUVECs. In both experimental models, EMPA treatment was associated with lower ROS production and DNA damage, including oxidative damage to purines and pyrimidines. This effect was not dose-dependent. EMPA was found to counteract this DNA damage by inhibiting ROS production. It appears that the EMPA induced indirect repair of DNA by inhibiting ROS production. [Display omitted] • 25-OHC-stimulated SMCs showed greater resistance to ROS generation compared to HUVECs. • 25-OHC-stimulated SMCs showed greater resistance to DNA damage compared to HUVECs. • EMPA treatment was associated with lower oxidative damage to purines and pyrimidines. • EMPA induced indirect repair of DNA by inhibiting ROS production. [ABSTRACT FROM AUTHOR]

Recent data showed that dabigatran can reduce not only procoagulatory effects but also block proinflammatory stimuli by inhibiting the expression of cytokines and chemokines and reducing thrombin-induced endothelial permeability. The aim of our study was to assess the effect of dabigatran on the integrity and inflammatory properties of endothelial cells stimulated by 25-hydroxycholesterol (25-OHC, oxysterol). HUVECs (Human Umbilical Vein Endothelial Cells) were stimulated with 25-hydroxycholesterol 10 µg/ml, dabigatran 100 ng/ml or 500 ng/ml and 25-hydroxycholesterol + dabigatran (100 ng/ml, 500 ng/ml). HUVEC integrity and permeability was measured in the RTCA-DP xCELLigence system and by the paracellular flux system. The mRNA expression of ICAM-1, VEGF, IL-33, MCP-1 and TNF-α was analyzed by Real-time PCR. Cell apoptosis and viability was measured by flow cytometry. VEGF protein concentration was assessed in supernatants by ELISA. VE-cadherin expression in endothelial cells was evaluated by confocal microscopy. Pre-stimulation of HUVECs with 25-OHC decreased endothelial cell integrity (p < 0.001) and increased the expression of IL-33, ICAM-1, MCP-1, VEGF, TNF-α mRNA (p < 0.01) compared to unstimulated controls. Following stimulation of HUVECs with dabigatran 100 ng/ml or 500 ng/ml restored HUVEC integrity interrupted by 25-OHC (p < 0.001). In HUVECs pre-stimulated with oxysterol, dabigatran stimulation decreased mRNA expression of the proinflammatory cytokines IL-33 and TNF-α, chemokines MCP-1 ICAM-1 and VEGF (p < 0.01). Dabigatran 500 mg/ml+ 25-OHC increased the endothelial expression of VE-cadherin as compared to 25-OHC (p < 0.01). Our findings suggest that dabigatran stabilizes the endothelial barrier and inhibits the inflammation caused by oxysterol. The effect of stimulation: 25-hydroxycholesterol (10 µg/ml)(A), dabigatran (100, 500 ng/ml) + 25-hydroxycholesterol (10 µg/ml)(B) on the barrier function and immune profile of Human Umbilical Vein Endothelial Cells (HUVECs). [Display omitted] • Dabigatran may reverse damaging effect of the 25-OHC on endothelial cells. • Dabigatran stabilized endothelial barrier interrupted by 25-OHC. • Dabigatran decreased the mRNA expression of ICAM-1, VEGF, IL-33, MCP-1 and TNFα elevated by 25-OHC in HUVECs. [ABSTRACT FROM AUTHOR]