Abstract: The present invention relates to a long-acting exendin-4 in which an albumin binding domain (ABD) and an anti-FcRn affibody are fused to exendin-4, and a use thereof. A long-acting exendin-4 according to the present invention has an in vivo half-life that is significantly increased over that of exendin-4, which is conventionally used as an agent for treating diabetes, and resultantly acts as a diabetes therapeutic agent, which is a conventional use of exendin-4, and also exhibits both an effect of treating other metabolic diseases and diabetes complications, such as obesity and fatty liver, and an effect of alleviating cognitive impairment caused by metabolic diseases.

Abstract: A method for diagnosing mild cognitive impairment according to an embodiment of the present disclosure includes obtaining a sample from a subject to be diagnosed, and measuring a level of tonicity-responsible enhancer binding protein (TonEBP) in the sample by using TonEBP antibody to determine if the measured level of the TonEBP is above a predetermined level. The measuring may further includes measuring a level of lipocalin-2 (LCN2) in the sample by using LCN2 antibody to determine if the measured level of the LCN2 is above a predetermined level.