Impact of thermal stress during incubation on gene expression in embryonic muscle of Peking ducks (Anasplatyrhynchos domestica).

Changes in temperature will influence poultry embryonic muscle development. However, little is known about the changes in molecular processes impacted by incubation temperature in avians. In this study, we investigated the effects of increasing the incubation temperature by 1°C from day 11-20 on the embryonic and posthatch skeletal muscle development of the Peking duck, and identified the differentially expressed genes using RNA-seq of leg muscle tissues. The results showed that altering the incubation temperature had immediate and long-lasting effects on phenotypic changes in the embryonic and post-hatching muscle development. It was shown that expression levels of total 1370 genes were altered in muscle tissues by the thermal treatments. The gene ontology (GO) analyses indicated that cellular processes including metabolism, cell cycle, catalytic activity, and enzyme regulatory activity may have involved in the muscle mass impacted by thermal manipulation. TGF-beta and insulin pathways as two classical muscle development related pathways may also involve in regulating muscle mass. These data may be helpful for understanding the physiological and biochemical processes of muscle development under environmental treatments in embryonic avians.

Three new 5,6,7,8-tetrahydro-2-(2-phenylethyl)chromones and one new dimeric 2-(2-phenylethyl)chromone from agarwood of Aquilaria crassna Pierre ex Lecomte in Laos.

Three new 5,6,7,8-tetrahydro-2-(2-phenylethyl)chromones and one new dimeric 2-(2-phenylethyl)chromone were isolated from the agarwood of Aquilaria crassna Pierre ex Lecomte in Laos. The structures of the isolates were elucidated by spectroscopic methods, and their configurations were determined via ROESY correlations, 3 J H-H coupling constants analyses, comparisons of chemical shifts and specific rotations with known compounds, and ECD calculation in the case of 1. Compounds 1-4 were evaluated for their cytotoxicity. Compounds 1 and 2 exhibited weak cytotoxicity toward HeLa cell line (IC50: 49.8 ± 1.2 µM) and K562 cell line (IC50: 42.66 ± 0.47 µM), respectively.