Early constant observation of the effect of deferoxamine mesylate on improvement of vascularized bone regeneration in SD rat skull critical size defect model / 北京大学学报(医学版)

OBJECTIVE@#To investigate the effect of local administration of deferoxamine mesylate (DFO) on vascularization and osteogenesis and its ability to maintain the activity of hypoxia inducible factor-1α (HIF-1α), by constantly observing early changes of vessel-like structures and bone tissues during bone defects healing.@*METHODS@#Skull critical bone defect models were constructed on a total of thirty male SD rats (6-8 weeks old). The rats were randomly divided into experimental group (DFO group) or control group (normal saline group). 300 μL 200 μmol/L DFO solution or normal saline was locally injected on the 4th day after the defect was made. On the 5th, 7th, 10th, 14th, and 28th days after surgery, three rats in each group were sacrificed respectively. HE staining and Masson staining were performed to observe new bone formation and mineralization. HIF-1α immunohistochemistry staining was performed to examine relative expression of protein. Qualitative analysis and comparation were performed by t-tests on relative expression of HIF-1α, numbers of blood vessels and percentages of mineralization tissues of new bone areas.@*RESULTS@#On the 5th, 7th, 10th, 14th and 28th days after surgery, the average numbers of blood vessels were 30.40±12.15, 62.00±17.87, 73.43±15.63, 40.00±7.84, 48.71±11.64 in the DFO group, and 18.75±6.63, 19.13±2.80, 51.35±16.21, 27.18±7.32, 30.88±13.43 in the control group. The number of blood vessels in the DFO group was significantly higher than that of the control group at each time point (P < 0.05). The mass of new bone in the DFO group was higher than that in the control group on the 14th and 28th days after surgery. The percentage of mineralization tissues of new bone area on the 14th and 28th days after injection were (27.73±5.93)% and (46.53±3.66)% in the DFO group, and (11.99±2.02)% and (31.98±4.22)% in the control group. The percentage of mineralization tissues in the DFO group was significantly higher than that of the control group at each time point (P < 0.001). The relative expression of HIF-1α in the DFO group compared with the control group was 2.86±0.48, 1.32±0.26, 1.32±0.32, 1.28±0.38 and 1.05±0.34 on the 5th, 7th, 10th, 14th and 28th days, with significant expression difference on the 5th day (P < 0.01).@*CONCLUSION@#Use of DFO in bone defects promotes vascularization and osteogenesis in the defect area, and maintains the protein activity of HIF-1α temporarily.

Two new Diels-Alder type compounds from cell cultures of Morus alba / 中草药

Objective To investigate the Diels-Alder adducts from cell suspension cultures of Morus alba. Methods A variety of column chromatography (CC) including silica gel CC, Sephadex LH-20 CC, C18 CC, and semi-preparative HPLC were used to separate Diels-Alder adducts from cell cultures of M. alba. Their structures were identified by physicochemical properties and various spectroscopic experiments, including MS, NMR, and ECD. Results Eight Diels-Alder adducts were obtained from the ethyl acetate extract of M. alba, and determined as mongolicin H (1), morbilisin J (2), mongolicin F (3), mulberrofuran G (4), artonin D (5), kuwanon R (6), morbilisin C (7), and mulberrofuran E (8). Conclusion Compounds 1-8 are all Diels-Alder adducts and show medium cytotoxic activity, and compounds 1 and 2 are new compounds.