Activation of the Aryl Hydrocarbon Receptor (AHR) induces human glutathione S transferase alpha 1 (hGSTA1) expression

Functional heterogeneity of immune defenses in molluscan oysters Crassostrea hongkongensis revealed by high-throughput single-cell transcriptome

Oyster is the worldwide aquaculture molluscan and evolves a complex immune defense system, with hemocytes as the major immune system for its host defense. However, the functional heterogeneity of hemocyte has not been characterized, which markedly hinders our understanding of its defense role. Here, we used the single-cell transcriptome profiling (scRNA-seq), which provides a high-resolution visual insight into its dynamics, to map the hemocyte and assess its heterogeneity in a molluscan oyster Crassostrea hongkongensis. By combining with the cell type specific RNA-seq, thirteen subpopulations belonging to granulocyte, semi-granulocyte, and hyalinocyte were revealed. The granulocytes mainly participated in immune response and autophagy process. Pseudo-temporal ordering of granulocytes identified two different cell-lineages. The hematopoietic transcription factors regulated networks controlling their differentiations were also identified. We further identified one subpopulation of granulocytes in immune activate states with the cell cycle and immune responsive genes expressions, which illustrated the functional heterogeneity of the same cell type. Collectively, our scRNA-seq analysis demonstrated the hemocytes diversity of molluscans. The results are important in our understanding of the immune defense evolution and functional differentiation of hemocytes in Phylum Mollusca.

Dietary Curcumin Alleviated Acute Ileum Damage of Ducks (Anas platyrhynchos) Induced by AFB1 through Regulating Nrf2-ARE and NF-κB Signaling Pathways

Aflatoxin B1 (AFB1) is a stable toxic metabolite threatening health of human and animal and widely contaminated animal feed and human food. This present study aimed to investigate the effects of dietary curcumin on ileum injury in ducks induced by AFB1 administration and explore its underlying mechanisms. Ducks (N = 450, one-day-old male) with a similar weight were randomly assigned to 3 groups, containing the control group, AFB1 group (60 μg AFB1 kg⁻¹ body weight) and curcumin (500 mg curcumin kg⁻¹ diet) + AFB1 group. AFB1 administration markedly increased the ileum damage, AFB1-DNA adducts in the plasma and oxidation stress and inflammation. Adding curcumin into diet protected the ileum against morphology damage induced by AFB1 administration, decreased AFB1-DNA adducts in the plasma and eliminated oxidation stress and inflammation in the ileum of ducks. Anti-oxidation and anti-inflammatory effects of curcumin could protect the ileum against acute damage via activating Nrf2-ARE signaling pathway and inhibiting NF-κB signaling pathway. Conclusively, curcumin was a dietary anti-oxidation and anti-inflammation agent via activating Nrf2-ARE signaling pathway and inhibiting NF-κB signaling pathway to protect ileum against acute damage induced by AFB1 administration.