RESUMEN
BACKGROUND: Beta-amyloid peptide (Aß) is the key protein in the pathogenesis of Alzheimer's disease, the most common age-related neurodegenerative disorder in humans. Aß peptide induced pathological phenotypes in different model organisms include neurodegeneration and lifespan decrease. However, recent experimental evidence suggests that Aß may utilize oligomerization and fibrillization to function as an antimicrobial peptide (AMP), and protect the host from infections. We used the power of Drosophila model to study mechanisms underlying a dual role for Aß peptides. RESULTS: We investigated the effects of Drosophila treatment with three Aß42 peptide isoforms, which differ in their ability to form oligomers and aggregates on the lifespan, locomotor activity and AMP genes expression. Aß42 slightly decreased female's median lifespan (by 4.5%), but the effect was not related to the toxicity of peptide isoform. The lifespan and relative levels of AMP gene expression in male flies as well as locomotor activity in both sexes were largely unaffected by Aß42 peptide treatment. Regardless of the effects on lifespan, Aß42 peptide treatment induced decrease in AMP genes expression in females, but the effects were not robust. CONCLUSIONS: The results demonstrate that chronic treatment with Aß42 peptides does not drastically affect fly aging or immunity.
Asunto(s)
Péptidos beta-Amiloides/toxicidad , Drosophila melanogaster/fisiología , Longevidad , Proteínas Citotóxicas Formadoras de Poros/genética , Animales , Drosophila melanogaster/genética , Femenino , Locomoción , Masculino , Isoformas de ProteínasRESUMEN
Recent experimental studies highlighted the role of hydrogen sulfide (H2S) in aging and longevity. The cystathionine ß-synthase (CBS) and cystathionine γ-lyase (CSE) are the key enzymes responsible for H2S production. Here we investigated the geroprotective effects of CSE and CBS overexpression in Drosophila. Overexpression of CSE did not affect a lifespan and decrease (mitochondrial form of CSE) or increase (cytoplasmic form of CSE) age dynamics of locomotor activity, while overexpression of CBS increase median (by 12.5%) and maximum (by 6.9%) lifespan and locomotor activity. Increasing of both CSE and CBS expression levels resulted in thermotolerance, but the resistance to combination of arid and food-free conditions decreased. The resistance to oxidative stress (paraquat) was not affected in flies with overexpression of CBS and cytoplasmic CSE, but decreased in flies overexpressing mitochondrial form of CSE. Thus, transgene overexpression of the CSE and CBS in Drosophila induce similar effects on stress-resistance and locomotor activity, however lifespan extending effect was revealed for CBS overexpression only.