A vascularized adipose organoid model using stromal vascular fraction cells from ruminant animals.

In vitro cell culture serves as an efficient system for studying animal cell behavior in a controlled setting. Here, we present a 3D culture model for forming ruminant adipose organoids using stromal vascular fraction cells. We describe steps for forming cell spheroids and growing them on a Matrigel-coated surface. We then detail procedures for inducing organoids to undergo angiogenesis and adipogenesis followed by capillary sprouting. This protocol can be utilized to study the interaction between blood vessels and adipocytes. For complete details on the use and execution of this protocol, please refer to Yu et al.1.

Synthesis of Azepinoindoles via Pd-Catalyzed C(sp2)-H Imidoylative Cyclization Reactions.

An efficient and convenient method for the construction of diverse free (N-H)-benzazepinoindoles by Pd-catalyzed C(sp2)-H imidoylative cyclization of 3-(2-isocyanobenzyl)-1H-indoles was developed. The reaction shows a wide substrate scope and can be scaled up, providing a practical route to valuable bioactive azepinoindoles.

Neonatal vitamin A administration increases intramuscular fat by promoting angiogenesis and preadipocyte formation.

To explore the effects and underlying mechanism of vitamin A on beef marbling fat development, angus steers were injected vitamin A at birth and 1 month of age and in vitro experiments were performed to investigate the effects of retinoic acid (RA) on angiogenesis and adipogenesis of intramuscular stromal vascular (SVF) cells. Results showed that vitamin A administration increased the intramuscular PDGFRα+ adipose progenitors, improved adipogenic potential of intramuscular SVF cells and dramatically upregulated VEGFA. At slaughter, vitamin A increased intramuscular triacylglycerols by 45% without affecting overall fatness. In a 3D culture system, RA promoted capillary sprout development and promoted the subsequent adipogenesis of intramuscular SVF cells by activating VEGFA/VEGFR2 signaling. However, during terminal adipogenesis, RA downregulated PPARγ, C/EBPα and inhibited lipid accumulation. In conclusion, vitamin A/RA upregulate VEGFA and stimulate intramuscular vascular capillary development, which increases intramuscular adipose progenitors and contributes to adipocyte formation. When administrated at neonatal stage, vitamin A promotes beef marbling development without affecting overall fatness.

Density functional theory study on the metal-support interaction between a Au9 cluster and an anatase TiO2(001) surface.

Noble metals supported on TiO2 surfaces have shown extraordinary photocatalytic properties in many important processes such as hydrogenation, water splitting, degradation of hazards, and so on. Using density functional theory calculations, this work has systematically investigated the microstructure and electronic structure of three different Au9 isomers loaded on anatase TiO2(001) surface. The calculated results show that the interaction between the Au9 cluster and the TiO2 support is closely related to the adsorption site and the stability of the Au9 cluster in the gas phase. The adsorption energy of the 2D configuration is larger than that of the 3D configuration of the Au9 cluster, owing to the stronger interactions between more adsorption sites. The stable adsorption site for Au9 clusters deposited on the anatase TiO2(001) surface tends to be the O2c-O2c hollow site. The presentation of the MIGS of the Au9 cluster, the disappearance of surface states of the TiO2(001) surface, and the shifting of the Fermi level from the top of the valence band to the bottom of the conduction band suggest strong interactions between the Au9 clusters and the TiO2(001) surface. Importantly, the electron transfer from the Au9 clusters to the TiO2 support occurs mainly through Au-O2c interactions, which are mainly localized at the contact layer of the Au9 clusters. These conclusions are useful to understand various physical and chemical properties of noble metal clusters loaded onto an oxide surface, and helpful to design novel metal/semiconductor functional composite materials and devices.