Enhanced activation of signaling pathway by recombinant human adiponectin from genome-edited chickens

Adiponectin (ADPN) exerts various cellular and metabolic functions by activating signaling pathways, including extracellular signal-regulated protein kinases 1 and 2 (ERK1/2) pathways, the protein kinase B (Akt) pathway, and the p38 mitogen-activated protein kinase (MAPK) pathway. However, generating functional recombinant human adiponectin (hADPN) in bacterial or mammalian cells is challenging. Although ADPN agonist peptides have been developed, problems like stability, solubility, and affinity for receptors remain. Recently, a genome-edited chicken bioreactor system was established, ensuring efficient ADPN production with optimal post-transcriptional modifications. We assessed the ability of egg white (EW)-derived hADPN, commercial hADPN, various ADPN agonist peptides, and globular ADPN on activation of the ERK1/2, Akt, and p38 MAPK pathways. EW-derived hADPN, abundant in hexamers and high molecular weight multimers, significantly phosphorylated ERK1/2 in serum-starved HEK293 cells after 15 min of treatment. Comparative analysis revealed that EW-derived hADPN and commercial hADPN induced greater phosphorylation of ERK1/2, Akt, and p38 MAPK than ADPN agonist peptides and globular ADPN, with EW-derived hADPN showing the highest activation. In summary, the finding that EW-derived hADPN strongly activates the ERK1/2, Akt, p38 MAPK signaling pathways highlights that an ADPN production system based on genome-edited chickens is an advantageous alternative to existing methods.