Table 1.

Molecular inhibition of T1R3 with siRNA has no impact on sweetener-induced protection against VEGF-induced barrier leak across the glomerular microvascular endothelial cell. GMVEC were transiently transfected with T1R3 siRNA or non-specific scrambled control siRNA (300 nM) for 24 h followed by exposure to artificial sweeteners aspartame (10 µM), saccharin (0.1 µM), and sucralose (0.1 µM) for 20 h. Cells were then exposed to VEGF (50 ng/mL) for a further 4 h. Permeability was assessed using FITC-dextran assay (panel a), and VE-cadherin cell-surface expression was measured using the whole-cell ELISA (panel b). n = 5–6. Data are expressed as mean with S.E.M * p < 0.05 vs. vehicle for VEGF.

(a)
siRNA	Permeability Ratio (Base/Insert)
	Scrambled				T1R3
Treatment:	Vehicle	Aspartame	Saccharin	Sucralose	Vehicle	Aspartame	Saccharin	Sucralose
Vehicle	1.77 ± 0.25	1.99 ± 0.57	1.88 ± 0.73	1.71 ± 0.58	1.95 ± 0.38	2.06 ± 0.61	1.89 ± 0.67	1.59 ± 0.73
VEGF	5.91 ± 0.62 *	2.05 ± 0.41	2.01 ± 0.60	1.89 ± 0.36	5.79 ± 0.55 *	1.83 ± 0.71	2.13 ± 0.82	1.98 ± 0.40
(b)
siRNA	VE-Cadherin Cell-Surface Expression (r.f.u.)
	Scrambled				T1R3
Treatment:	Vehicle	Aspartame	Saccharin	Sucralose	Vehicle	Aspartame	Saccharin	Sucralose
Vehicle	4038 ± 693	4126 ± 827	4150 ± 1017	4061 ± 904	4183 ± 1027	5199 ± 757	4289 ± 863	4890 ± 1007
VEGF	971 ± 183 *	4090 ± 938	4281 ± 1105	4135 ± 1036	891 ± 130 *	4937 ± 812	3980 ± 1170	4136 ± 1021