Transcriptomic Analysis on Pectoral Muscle of European Meat Pigeons and Shiqi Pigeons during Embryonic Development.

In avian muscle development, embryonic muscle development determines the number of myofibers after birth. Therefore, in this study, we investigated the phenotypic differences and the molecular mechanism of pectoral muscle development of the European meat pigeon Mimas strain (later called European meat pigeon) and Shiqi pigeon on embryonic day 6 (E6), day 10 (E10), day 14 (E14) and day 1 after birth (P1). The results showed that the myofiber density of the Shiqi pigeon was significantly higher than that of the European meat pigeon on E6, and myofibers with a diameter in the range of 50~100 µm of the Shiqi pigeon on P1 were significantly higher than those of European meat pigeon. A total of 204 differential expressed genes (DEGs) were obtained from RNA-seq analysis in comparison between pigeon breeds at the same stage. DEGs related to muscle development were found to significantly enrich the cellular amino acid catabolism, carboxylic acid catabolism, extracellular matrix receptor interaction, REDOX enzyme activity, calcium signaling pathway, ECM receptor interaction, PPAR signaling pathway and other pathways. Using Cytoscape software to create mutual mapping, we identified 33 candidate genes. RT-qPCR was performed to verify the 8 DEGs selected-DES, MYOD, MYF6, PTGS1, MYF5, MYH1, MSTN and PPARG-and the results were consistent with RNA-seq. This study provides basic data for revealing the distinct embryonic development mechanism of pectoral muscle between European meat pigeons and Shiqi pigeons.

[Mechanism of Hematopoietic Reconstruction in Mice Treated with Danggui Buxue Decoction combined with Muscle-Derived Stem Cell Transplantation].

OBJECTIVE: To investigate the mechanism of hematopoietic reconstruction in mice treated with Danggui Buxue Decoction (DBD) combined with the muscle-derived stem cell transplantation (MDSCT). METHODS: Female Kunming mice were randomly divided into the 6 groups: irradiation model, the bone marrow transplantation, the MDSC transplantation, the DBD 1 (4.5 g/kg), 2 (13.5 g/kg), and 3 (22.5 g/kg) + MDSC transplantation. After a week of oral administration of normal saline or different doses of DBD, The mice were exposied to 8 Gy 137Cs γ ray and were followed by bone marrow or MDSC transplantation. The expression levels of Notch1, Jagged1 and Hes1 in bone marrow, thymus and spleen were measured at 3 and 8 weeks after irradiation and transplantation. RESULTS: In the bone marrow, 3 weeks after above-mentioned treatment, the expression of Notch1 mRNA increased obviously and the expression of Jagged1, Hes1 mRNA decreased obviously in each intervention group, compared with the irradiation model group. 8th week after treatment, the expression of Notch1 mRNA decreased obviously in each intervention group, the Jagged1 mRNA expression decreased obviously except the bone marrow group, and Hes1 mRNA expression increased (P＜0.05) in each intervention group. 3 weeks after treatment, compared with the irradiation model group, the expression of Notch1 mRNA in the thymocytes increased only in DBD1+MDSC group, Jagged1, Hes1 mRNA was increased in the MDSC transplantation group and the DBD1、2+MDSC group. 8th week after treatment, the expression of Notch1, Jagged1 mRNA expression decreased in each intervention group, the expression of Hes1 mRNA increased obviously in the MDSC transplantation group and the DBD1、2+MDSC group (P＜0.05). In the spleen, 3 weeks after treatment, the expression of Notch1, Jagged1 mRNA in the spleen of each intervention group decreased obviously, compared with the irradiation model group. The expression of Jagged1, Hes1 mRNA in each intervention group were increased obviously 8th week after treatment (P＜0.05). CONCLUSION: MDSC transplantation after pretreatment of DBD can improve the hematopoietic reconstitution in mice with lethal dose radiation damage. Notch1、Jagged1 and Hes1 play different roles in this process, but the concrete mechanism needs to be further studied.