ABSTRACT
BACKGROUND: Morinda officinalis oligosaccharide is the main active ingredient of morinda officinalis extract,which can promote the angiogenesis of ischemic tissue, but the mechanism is unknown. At present, there are two ways for endothelial repair:vascular endothelial cell division or differentiation from vascular endothelial progenitor cells in the peripheral blood. Here, we attempted to explain the pro-angiogenesis mechanism of morinda officinalis oligosaccharide by exploring whether there is a correlation between morinda officinalis oligosaccharide and the biological function of vascular endothelial progenitor cells, thereby providing experimental reference for new drug development. OBJECTIVE: To observe the effect of morindae officinalis oligosaccharide on the proliferation, differentiation and paracrine of vascular endothelial progenitor cells. METHODS: Vascular endothelial progenitor cells were isolated from healthy human peripheral blood, and divided into two groups: control group (without morindae officinalis oligosaccharide) and experimental group (with 0.15 g/L morindae officinalis oligosaccharide), followed by 48 hours of in vitro culture.The proliferation of vascular endothelial progenitor cells was tested by fluorescent staining;the ratio of vascular endothelial progenitor cells expressing CD31 was detected by flow cytometry; and the levels of vascular endothelial growth factor, stromal cell-derived factor 1 and interleukin 8 were analyzed by enzyme-linked immunosorbent method. RESULTS AND CONCLUSION: The percentage of vascular endothelial cells expressing CD34, CD133 or VEGFR- 2 was (84.72±4.34)%. After 48 hours of culture by 0.15 g/L morindae officinalis oligosaccharide, the proliferation rate and the positive expression of CD31 in the experimental group were significantly higher than those in the control group (P < 0.05). The levels of vascular endothelial growth factor, stromal cell-derived factor 1 and interleukin 8 in the experimental group were also higher than those in the control group (P < 0.05). To conclude, morindae officinalis oligosaccharide can promote the proliferation and differentiation of vascular endothelial progenitor cells, and meanwhile, it can stimulate the release of vascular endothelial growth factor, stromal cell-derived factor 1 and interleukin 8 from vascular endothelial progenitor cells through the paracrine pathway. Consequently, it is a potential drug for myocardial ischemic diseases.
ABSTRACT
This study was purposed to evaluate ABL tyrosine kinase point mutations in imatinib-treated chronic myeloid leukemia (CML) patients and their clinical significance. 51 bone marrow samples from 28 imatinib-resistant patients and 10 newly diagnosed CML patients were collected. ABL kinase domain of bcr-abl allele was amplified by nested reverse transcription-polymerase chain reaction, followed by purifying, directly sequencing and sequence homology analysis of amplified products in order to determine the existence and type of point mutation. The results showed that the point mutations were found in 12 of 38 patients, and all the 12 ones progressed to advanced disease or death. 2 patients showed Met351Thr mutation, 7 patients showed Glu252His, 2 patients showed Glu279Lys, the other types were Glu255Val and Glu355Gly, each of which was tested in one patient. The incidence of the point mutation was 17.6%, 45.5% and 44.4% in chronic, accelerated and blast phase respectively. The incidences of point mutation in hematologically and genetically resistant patients were 50% (5/10) and 44.4% (8/18), and the 95% confidence interval (CI) was 12.3% - 87.7% and 19% - 69.9% respectively. It is concluded that ABL kinase point mutation is an important mechanism of imatinib resistance, monitoring the ABL kinase domain point mutation is helpful to estimating the prognosis and adjusting the therapeutic strategy.