In contrast, a more recent 20-week pilot clinical trial in non-diabetic patients with MCI related to AD reported metformin-induced alterations in plasma and CSF proteins associated with inflammation (AZU1, CCL11, IL-32), apoptosis (CASP-3), and neuroprotection (PRTN3), supporting potential neuroprotective effects of metformin beyond its established antidiabetic action [307]. Here, AZU1 is linked to Alzheimer disease.