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BackgroundEdible Bird’s nest (EBN) is an antioxidant-rich supplement that is popular in many parts of Asia. Its antioxidant and anti-inflammatory properties have been reported using in vitro system. This paper aimed to determine the antioxidant and anti-inflammatory effects of EBN in in high fat diet induced rats model.MethodsWe evaluate if those properties can be translated in rats. High fat diet (HFD) was fed to rats for 12 weeks to determine its effects on oxidative stress and inflammation, and compared with HFD + Simvastatin and HFD + EBN (2.5 or 20 %). Weights were measured weekly, while serum and hepatic markers of oxidative stress (total antioxidant status and TBARS) and inflammation (interleukin 6 [IL-6], C-reactive protein [CRP] and tumor necrosis factor alpha [TNF-α]) were determined at the end of the intervention. In addition, transcriptional changes in hepatic antioxidant (superoxide dismutase, glutathione reductase, glutathione peroxidase) and inflammation (C-reactive protein, chemokine [C-C] motif 2, nuclear factor kappa beta 1 and tumor necrosis factor alpha) genes were evaluated.ResultsThe results showed increases in oxidative stress (raised TBARS and lowered total antioxidant status) and inflammatory markers (raised CRP, IL-6 and TNF-α) in HFD induced rats with corresponding attenuation of antioxidant gene expression and potentiation of inflammatory gene expression. EBN on the other hand attenuated the HFD-induced inflammation and oxidative stress and produced overall better outcomes in comparison with simvastatin.ConclusionsIn aggregate, the results support the evidence-based utilization of EBN as a supplement for preventing obesity-related inflammation and oxidative stress in rats. These promising results can open up opportunities for translating the benefits of EBN to humans.

Metal‐containing polymer networks are ubiquitous in biological systems, and their unique structures enable a variety of fascinating biological behaviors. Cuticle of mussel byssal threads, containing Fe‐catecholate complexes, shows remarkably high hardness, high extensibility, and self‐healing capability. Understanding strengthening and self‐healing mechanisms is essential for elucidating animal behaviors and rationally designing mussel‐inspired materials. Here, direct evidence of Fe3+ and Fe2+ gradient distribution across the cuticle thickness is demonstrated, which shows more Fe2+ inside the inner cuticle, to support the hypothesis that the cuticle is a functionally graded material with high stiffness, extensibility, and self‐healing capacity. The mechanical tests of the mussel threads show that both strength and extensibility of the threads decrease with increasing oxygen contents, but this property degradation can be restored upon removing the oxygen. The first‐principles calculations explain the change in iron coordination, which plays a key role in strengthening, degradation, and self‐healing of the polymer networks. The oxygen absorbs on metal ions, weakening the iron‐catecholate bonds in the cuticle and collagen core, but this process can be reversed by sea water. These findings can have important implications in the design of next‐generation bioinspired robust, highly extensible materials, and catalysis.