Geroprotective potential of genetic and pharmacological interventions to endogenous hydrogen sulfide synthesis in Drosophila melanogaster.

Endogenous hydrogen sulfide (H2S) is a gasotransmitter with a wide range of physiological functions. Aging is accompanied by disruption of H2S homeostasis, therefore, interventions to the processes of H2S metabolism to maintain its balance may have geroprotective potential. Here we demonstrated the additive geroprotective effect of combined genetic and pharmacological interventions to the hydrogen sulfide biosynthesis system by overexpression of cystathionine-ß-synthase and cystathionine-γ-lyase genes and treatment with precursors of H2S synthesis cysteine (Cys) and N-acetyl-L-cysteine (NAC). The obtained results suggest that additive effects of genetic and pharmacological interventions to H2S metabolism may be associated with the complex interaction between beneficial action of H2S production and prevention of adverse effects of excess H2S production by Cys and NAC treatment.

Amyloid-ß peptides slightly affect lifespan or antimicrobial peptide gene expression in Drosophila melanogaster.

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.