The aim of this work was to investigate developmental changes in cell proliferation and apoptosis in normal duck bursa of Fabricius using flow cytometry and immunohistochemistry. Studies were carried out on Tianfu ducks on days 24 and 27 of embryogenesis (E24 and E27) along with days 20, 70, and 200 of postnatal development (P20, P70, and P200). Results showed that the percentage of G0/G1 bursa cells significantly increased between E24 and P200 while the percentage of cells in the S phase or G2 + M phase as well as the proliferating index obviously decreased during the same period. Proliferation cell nuclear antigen was detected in lymphocyte and interfollicular epithelium. The proliferative lymphocyte density tended to decrease from E24 to P200. Apoptotic bodies in macrophages, free apoptotic bodies, or nuclei with condensed chromatin in lymphocytes in follicles were identified by transferase-mediated dUTP nick-end labeling. Both flow cytometry and microscopic analysis reveal that the proportion of apoptotic cells and apoptotic lymphocyte density increased from E24 to P20, fell on P70, then rose again on P200. Our foundings demonstrate that cell proliferation decreases and apoptosis increases with age. These changes may account for duck bursa development and involution.
Animals ; *Apoptosis ; Bursa of Fabricius/*cytology/embryology/growth & development/*physiology ; Cell Proliferation ; Ducks/embryology/*physiology ; Embryo, Nonmammalian/cytology/embryology ; Embryonic Development ; Epithelium/physiology ; Female ; Flow Cytometry/veterinary ; Immunohistochemistry/veterinary ; Lymphocytes/physiology ; Male

Pdx-1, an important transcription factor highlighting in the early pancreatic development, islet functions and pancreatic disorders, needs to be more investigated in zebrafish, and siRNA is still seldom applied in zebrafish embryo-related research. Our aim was to explore the role of pdx-1 in pancreatic development of zebrafish embryos by using siRNA approach. Microinjection, reverse transcriptase-PCR (RT-PCR), in situ hybridization and immunofluorescent staining were used in this research, and the morphology of the islet in normal zebrafish embryos, and in those treated with the siRNA specific to pdx-1 (siPDX-1) or siGFP was observed and compared. The expression of pdx-1 was detected in the stages of 1-cell, 2-cell, 4-cell, 8-cell, 16-cell, 16-hour by RT-PCT. The in situ hybridization and immunofluorescent staining results showed that siPDX-1 disturbed the formation of the islet in zebrafish embryos. Pdx-1 played multiple roles in maintaining the phenotype of the islet during embryogenesis in zebrafish.
Embryo, Nonmammalian ; Homeodomain Proteins/genetics ; Homeodomain Proteins/*metabolism ; Islets of Langerhans/cytology ; Islets of Langerhans/*embryology ; Islets of Langerhans/metabolism ; RNA Interference ; RNA, Small Interfering/*genetics ; Trans-Activators/genetics ; Trans-Activators/*metabolism ; Zebrafish

Our previous report has demonstrated that 5-formylhonokiol (FH), a derivative of honokiol (HK), exerts more potent anti-proliferative activities than honokiol in several tumor cell lines. In present study, we first explored the antiangiogenic activities of 5-formylhonokiol on proliferation, migration and tube formation of human umbilical vein endothelial cells (HUVECs) for the first time in vitro. Then we investigated the in vivo antiangiogenic effect of 5-formylhonokiol on zebrafish angiogenesis model. In order to clarify the underlying molecular mechanism of 5-formylhonokiol, we investigated the signaling pathway involved in controlling the angiogenesis process by western blotting assay. Wound-healing results showed that 5-formylhonokiol significantly and dose-dependently inhibited migration of cultured human umbilical vein enthothelial cells. The invasiveness of HUVEC cells was also effectively suppressed at a low concentration of 5-formylhonokiol in the transwell assay. Further F-actin imaging revealed that inhibitory effect of 5-formylhonokiol on invasion may partly contribute to the disruption of assembling stress fiber. Tube formation assay, which is associated with endothelial cells migration, further confirmed the anti-angiogenesis effect of 5-formylhonokiol. In in vivo zebrafish angiogenesis model, we found that 5-formylhonokiol dose-dependently inhibited angiogenesis. Furthermore, western blotting showed that 5-formylhonokiol significantly down-regulated extracellular signal-regulated kinase (ERK) expression and inhibited the phosphorylation of ERK but not affecting the total protein kinase B (Akt) expression and related phosphorylation, suggesting that 5-formylhonokiol might exert anti-angiogenesis capacity via down-regulation of the ERK signal pathway. Taken together, these data suggested that 5-formylhonokiol might be a viable drug candidate in antiangiogenesis and anticancer therapies.
Actins/metabolism ; Angiogenesis Inhibitors/*pharmacology ; Animals ; Antineoplastic Agents, Phytogenic/pharmacology ; Biphenyl Compounds/*pharmacology ; Blotting, Western ; Cell Line, Tumor ; Cell Movement/drug effects ; Cell Proliferation/drug effects ; Cells, Cultured ; Dose-Response Relationship, Drug ; Drugs, Chinese Herbal ; Embryo, Nonmammalian/drug effects/metabolism ; Endothelium, Vascular/*drug effects/metabolism ; Extracellular Signal-Regulated MAP Kinases/*antagonists & inhibitors/metabolism ; Humans ; Lignans/*pharmacology ; Neovascularization, Physiologic/*drug effects ; Signal Transduction/*drug effects ; Umbilical Veins/cytology ; Wound Healing ; Zebrafish/embryology/metabolism