Abalone peptide increases stress resilience and cost-free longevity via SKN-1-governed transcriptional metabolic reprogramming in C. elegans

A major goal of healthy aging is to prevent declining resilience and increasing frailty, which are associated with many chronic diseases and deterioration of stress response. We have successfully used loss-or-gain model of stress survival to quantify organismal resilience. As a proof of concept, this is demonstrated in C. elegans exposed to increasing oxidative stress induced by exogenous paraquat and with proteotoxic stress caused by endogenous polyQ and Aβ aggregation, respectively. Based on this, we reveal that abalone peptide AbaPep#07 (SETYELRK) not only promotes survival resilience against paraquat-induced oxidative stress but also confers protection against polyQ- or Aβ-mediated behavioral dysfunction in C. elegans, indicating its capacity against stress and neurodegeneration. Importantly, we further show that the peptide increases physical fitness of aged C. elegans and extends life span without compromise of growth and reproduction, demonstrating its cost-free prolongevity activity. Moreover, we reveal that the peptide induces differential expression of a number of genes, including innate immune, lipid metabolism and metabolic detoxification genes, which are associated with the SKN-1/Nrf transcription factor. Collectively, our findings demonstrate that the novel abalone cryptide AbaPep#07 increases stress survival resilience and cost-free longevity via SKN-1/Nrf-governed transcriptional reprogramming and provide an insight into the neuroprotective and health-promoting potential of cryptides as proteostasis regulators. To identify genes responsive to the peptide, we performed global transcriptomic analysis using RNA-seq to compare aged C. elegans (day 10 of adulthood) with and without AbaPep#07 treatment from L4 stage.