Protection of goose adiponectin-derived peptide gADP3 on LPS-induced thymus and spleen injury in goose

This study aims to evaluate the protective effects of goose-derived adiponectin peptide gADP3 on Lipopolysaccharide (LPS)-induced damage to goose thymus and spleen. LPS-induced inflammation was induced via intraperitoneal injection, with interventions using gADP3 and AdipoRon (positive control). Pathological changes in thymus and spleen tissues were observed. Levels of biochemical indicators related to inflammation, oxidative stress, and immunity in blood and tissue were measured. Additionally, tissue expression of key factors associated with inflammation, adiponectin receptors, and signaling pathways involved in inflammation and oxidative stress was assessed. The results showed that gADP3 and AdipoRon improved the histology of the thymus and spleen, reduced the infiltration of inflammatory cells, decreased the levels of the proinflammatory factors IL-6 and TNF-α, increased the levels of the anti-inflammatory factor IL-10, and alleviated the immune inflammatory responses induced by LPS. They also reduced the content of MDA in thymus and spleen tissues and enhanced GSH-Px activity in the thymus, thereby improving the status of oxidative stress. In terms of molecular mechanisms, both gADP3 and AdipoRon restored AdipoR1 mRNA expression and increased AMPK mRNA levels in the thymus. AdipoRon also restored AMPK protein levels. In the spleen, AdipoRon increased the expression of both AdipoR1 mRNA and protein, while gADP3 increased the mRNA expression of both AdipoR2 and AMPK. Furthermore, this study also found that LPS stimulation significantly upregulated the mRNA expression levels of NF-κB p65, MyD88, and TLR4 in the thymus, and markedly increased MyD88 protein levels. gADP3 and AdipoRon interventions significantly reduced mRNA and protein expression levels of these molecules. In spleen tissue, LPS stimulation significantly upregulated TLR4 mRNA levels and markedly increased NF-κB p65 and MyD88 protein levels, while gADP3 and AdipoRon interventions significantly reduced mRNA and protein expression levels of these molecules. In summary, our findings reveal that gADP3 alleviates immune and inflammatory damage in thymus and spleen tissues, thereby maintaining immune homeostasis in goslings and producing effects similar to those of AdipoRon.