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A large amount of copper (Cu) used in production activities can lead to the enrichment of Cu in the environment, which can cause toxicity to animals. However, the toxicity mechanism of Cu on the cerebrum is still uncertain. Hence, a total of 240 chickens were separated into four groups in this study to reveal the potential connection between mitophagy and endoplasmic reticulum (ER) stress-mediated apoptosis in the chicken cerebrum in the case of excess Cu exposure. The cu exposure situation was simulated by diets containing various levels of copper (11 mg/kg, control group; 110 mg/kg, group I; 220 mg/kg, group II and 330 mg/kg, group III) for 49 days. The results of histology showed that vacuolar degeneration was observed in the treated groups, and the mitochondria swell and autophagosomes formation were found under excess Cu treatment. Additionally, the expression of mitophagy (PINK1, Parkin, LC3I, LC3II and p62) and ER stress (GRP78, PERK, ATF6, IRE1α, XBP1, CHOP, and JNK) indexes were significantly upregulated under excess Cu exposure. Furthermore, the mRNA and protein expression of Bcl-2 were decreased, while Bak1, Bax, Caspase12, and Caspase3 were increased compared to the control group. In summary, this study demonstrated that an overdose of Cu could induce mitophagy and ER stress-mediated apoptosis in the chicken cerebrum. These findings revealed an important potential connection between Cu toxicity and cerebrum damage, which provided a new insight into Cu neurotoxicity.

Copper (Cu) is a common environmental pollutant which has been identified to cause toxic effects on animal bodies. MicroRNAs (miRNAs) are a type of non-coding RNAs involved in the regulation of various cellular activities including autophagy, but the potential regulatory mechanisms after excess Cu intake are still uncertain. Our previous study has prompted that Cu exposure reduced liver miR-455-3p levels. Herein, miR-455-3p was found to be an important molecule in the regulation of Cu-induced autophagy in vivo and in vitro. Histopathology observation of liver tissue indicated that Cu-induced severe hepatic damage including cellular swelling and vacuolization. Meanwhile, excessive Cu exposure not only heighten the mRNA and protein expression levels of Beclin1, Atg5, LC3Ⅰ and LC3Ⅱ, but also decreased miR-455-3p levels. In vitro experiment, Cu-induced autophagy can be attenuated by miR-455-3p overexpression. Additionally, oxidative stress-responsive 1 (OXSR1) was identified as a direct downstream target of miR-455-3p by dual luciferase reporter assays. Moreover, knockdown of OXSR1 can attenuate the autophagy induced by Cu treatment and the miR-455-3p inhibitor. Overall, the miR-455-3p-OXSR1 axis works as a regulator of autophagy under Cu stress, which provides a basis for further revealing the mechanism of chronic Cu poisoning.

An ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was established for the quantitative detection of bovine lactoferrin in dairy products. The samples were treated by degreasing and tryptic hydrolysis. Proteins of bovine lactoferrin and peptides were identified using ultra performance liquid chromatography-quadrupole/electrostatic orbitrap-high resolution mass spectrometry (UPLC-Q/Exactive-HRMS) and analyzed by Protein Pilot software. Eight species-specific marker peptides of bovine lactoferrin were identified by comparison of the basic local alignment search tool (BLAST) with the Uniprot database. Three markers with high response strength and stability were chosen for further quantitative research by UPLC-triple quadrupole mass spectrometry (QqQ-MS). The method showed a good linear relationship within its own range. The limits of detection and limits of quantification were 0.023-0.041 and 0.077-0.137 mg/kg, respectively. The observed recoveries were in the range of 93.8%-103.9%. The intra-day and inter-day RSDs were lower than 8.8% and 9.5%, respectively. This method presents various advantages such as strong anti-interference, high sensitivity and reproducibility, and it is suitable for the quantitative analysis of bovine lactoferrin in dairy products.

Atlantic salmon is often adulterated or substituted by rainbow trout with much lower price and quality. However, it is extremely difficult to distinguish Atlantic salmon and rainbow trout due to their similar appearance and close relationship in species. In the present work, untargeted and targeted proteomics approaches were both implemented to identify species-specific peptide biomarkers of Atlantic salmon and rainbow trout. Potential peptide biomarkers were obtained through matching HRMS data with UniProt database, screened by BLAST and then verified with real samples. Five peptide biomarkers were identified each for Atlantic salmon and rainbow trout. MRM method was established for quantitative measurement of rainbow trout Adulteration in Atlantic salmon, showing high sensitivity and repeatability. The biomarker peptide GDPGPGGPQGEQGVVGPAGISGDK was used for quantification. The limit of the detection (LOD) of adulteration of rainbow trout is 0.19%, and the limit of quantitation (LOQ) is 0.62%. Furthermore, this method was successfully applied to analyze a number of Atlantic salmon and Rainbow trout samples from different regions and different batches, as well as commercially available processed products.

Dynamic structural color has attracted considerable attentions due to its good tunable characteristics. Here, an ultrathin asymmetric Fabry-Perot (FP)-type structural color with phase-change material VO2 cavity is proposed. The color-switching performance can be realized by temperature regulation due to the reversible monoclinic-rutile phase transition of VO2. The various, vivid structural color can be generated by simply changing the thickness of VO2 and Ag layers. Moreover, the simple structural configuration enables a large-scale, low-cost preparation on both rigid and flexible substrates. Accordingly, a flexible dynamic structural color membrane is adhered on a cup with a curved surface to be used for temperature perception. The proposed dynamic structural color has potential applications in anti-counterfeiting, temperature perception, camouflage coatings among other flexible optoelectronic devices.