GLP1R and Alzheimer disease: However, another study evaluating different insulin-stimulating agents, including SU, repaglinide, GLP1 analogs, DPP4i, GLP1, metformin and pioglitazone reported no significant effects on CSF markers of AD (Aβ42, total tau, p-tau, total tau/Aβ42) in patients with T2D [318].