In type 2 diabetic patients with progressive MCI or AD, plasma levels of two neuroexosome-derived mitochondrial proteins—NADH ubiquinone oxidoreductase core subunit S3 (NDUFS3) and succinate dehydrogenase complex subunit B (SDHB)—were lower than in cognitively normal patients [181]. The gene discussed is NDUFS3; the disease is type 2 diabetes mellitus.