GPBAR1 and Cognitive impairment: The mouse model of cognitive impairment was established by a single intracerebroventricular (ICV) injection of STZ (3.0 mg/kg), and we found that TGR5 activation by its agonist INT-777 (1.5 or 3.0 μg/mouse, ICV injection) ameliorated spatial memory impairment in the Morris water maze and Y-maze tests.