Embodiments of the present disclosure pertain to methods of treating or preventing Alzheimer's disease or symptoms of Alzheimer's disease in a subject by administering to the subject an active agent that includes an adenovirus-36 E4orf1 protein, a nucleic acid encoding an adenovirus-36 E4orfl protein, or combinations thereof. Additional embodiments of the present disclosure pertain to the active agents of the present disclosure for use in the treatment or prevention of Alzheimer's disease or symptoms of Alzheimer's disease.