【Abstract】 Objective To observe the effects of Angelica dahurica extracts on the biological characteristics of human keratinocytes (KC) in vitro and to explore the possible mechanism in promoting wound healing. Methods HaCaT cells of passage 5 from KC were used during the experiment. Different concentrations (5 × 10-2, 5 × 10-3, 5 × 10-4, and 5 × 10-5 g/L) of Angelica dahurica extracts, which was obtained by 95% ethanol from Angelica dahurica raw material, were prepared by DMEM containing 0.25% fetal bovine serum (FBS). After the extracts at different concentrations were respectively used for KC culture for 5 days, the cell proliferation activities were detected by MTT, and DMEM containing 0.25% FBS served as the negative control. According to the cell proliferation activity, the optimal concentration was determined. KC was further treated with Angelica dahurica extracts of the optimal concentration (experimental group) or with DMEM containing 0.25% FBS (control group) for 48 hours. The cell cycle was tested by flow cytometry. Cyclin D1 and Caspase-3 mRNA levels were also detected by real-time fluorescent quantitative PCR technique. Results Angelica dahurica extracts at concentrations of 5 × 10-4, 5 × 10-3,and 5 × 10-2 g/L could significantly enhance KC proliferation, showing significant differences in absorbance (A) values compared with that of control group (P lt; 0.05) with an optimal concentration of 5 × 10-3 g/L. At this concentration, an increased percentage of S and G2/M phase cells and a decreased percentage of G0/G1 phase cells were detected, showing significant differences when compared with control group (P lt; 0.05). Real-time fluorescent quantitative PCR revealed that the cyclin D1 and Caspase-3 mRNA levels of experimental group was significantly down-regulated, showing significant differences when compared with control group (P lt; 0.05). Conclusion Angelica dahurica extracts can promote the proliferation of KC, accelerate the cell cycle of KC by down-regulating mRNA expressions of cyclin D1, and inhibit apoptosis by down-regulating mRNA expressions of Caspase-3. These effects might enhance the process of wound healing by expediting the process of epithelization.
To isolate and culture adi pose-derived stem cells (ADSCs), and to study the effects of the conditioned medium of ADSCs (ADSC-CM) treated with insul in on HaCaT cells. Methods ADSCs were isolated from adipose tissue donated by the patient receiving abdominal surgery and were cultured. The concentration of ADSCs at passage 3 was adjusted to 5 × 104 cells/mL. The cells were divided into 2 groups: group A in which the cells were incubated in 1 × 10-7 mol/ Linsul in for 3 days, and group B in which the cells were not treated with insul in. ADSC-CM in each group was collected 3 days after culture, then levels of VEGF and hepatocyte growth factor (HGF). HaCaT cells were cultured and the cells at passage 4 were divided into 4 groups: group A1, 0.5 mL 2% FBS and 0.5 mL ADSC-CM from group A; group B1, 0.5 mL 2% FBS and 0.5 mL ADSC-CM from group B; group C1, 1 mL 2% FBS of 1 × 10-7 mol/ L insul in; group D1, 1 mL 2%FBS. Prol iferation of HaCaT cells was detected by MTT method 3 days after culture, apoptosis rate of HaCaT cells was measured by Annexin V-FITC double staining 12 hours after culture, and the migration abil ity was measured by in vitro wound-heal ing assay 0, 12, 24, 36 and 48 hours after culture. Results The level of VEGF in groups A and B was (643.28 ± 63.57) and (286.52 ± 46.68) pg/mL, respectively, and the level of HGF in groups A and B was (929.95 ± 67.52) and (576.61 ± 84.29) pg/mL, respectively, suggesting differences were significant between two groups (Plt; 0.05). Cell prol iferation detection showed the absorbance value of HaCaT cells in group A1, B1, C1 and D1 was 0.881 ± 0.039, 0.804 ± 0.041, 0.663 ± 0.027 and 0.652 ± 0.042, respectively, suggesting there was significant difference between groups A1 and B1 and groups C1 and D1 (P lt; 0.01), group A1 was significantly higher than group B1 (P lt; 0.05). The apoptosis rate of HaCaT cells in groups A1, B1, C1 and D1 was 5.23% ± 1.98%, 8.82% ± 2.59%, 31.70% ± 8.85% and 29.60% ± 8.41%, respectively, indicating there was significant difference between groups A1 and B1 and groups C1 and D1 (P lt; 0.05), group B1 was significantly higher than group A1 (P lt; 0.05). The migration distance of HaCaT cells in groups A1, B1,C1 and D1 at 36 hours was (0.184 6 ± 0.019 2), (0.159 8 ± 0.029 4), (0.059 2 ± 0.017 6) and (0.058 2 ± 0.012 3) mm, respectively, whereas at 48 hours, it was (0.231 8 ± 0.174 0), (0.205 1 ± 0.012 1), (0.079 2 ± 0.008 1) and (0.078 4 ± 0.011 7) mm, respectively, suggesting there were significant differences between groups A1 and B1 and groups C1 and D1 at 36 and 48 hours (P lt; 0.01), group A1 was significantly higher than group B1 (P lt; 0.05) at 36 and 48 hours, no significant difference was evident at other time points(P gt; 0.05). Conclusion ADSCs treated with insul in can significantly promote the prol iferation and the migration of HaCaT cells and inhibit their apoptosis.
Objective To establ ish an efficient and stable culture method of human umbil ical vein endothel ial cells (HUVECs) in vitro so as to provide good source of seed cells for tissue engineered vascular grafts and for precl inical research. Methods The umbil ical cords were harvested from full-term normal delivered neonates, which were perfused with0.1% collagenase II by self-made needle and were digested at 37 and 5% CO2 humidified incubator. The HUVECs were cultured in endothel ial culture medium (ECM) containing 5% fetal bovine serum (FBS) and 1% endothel ial cell growth factor (ECGS). HE staining of the umbil ical cords before and after digestion was used to observe the detachment of HUVECs, flow cytometry to detect the purity of primary HUVECs, and inverted phase contrast microscope to observe the morphology of the cultured HUVECs. The growth of the 3rd passage cells was measured by MTT assay; immunocytochemical technique and matrigelbased capillary-l ike tube formation assay were carried out to identify the function of HUVECs. Results After digestion of 0.1% collagenase II, marked HUVECs detachment was observed with complete digestion. The purity of the HUVECs was 99.56% by digestion of 0.1% collagenase II at 37 and 5% CO2 humidified incubator for 15 minutes. Primary HUVECs showed a cobblestone or pitching stone-l ike appearance in vitro, forming a confluent monolayer cells after 2-3 days of culture. MTT assay demonstrated that HUVECs showed the fastest growth speed at 3 to 4 days, and showed growth of cell fusion at about 5 days. Immunocytochemistry showed that HUVECs highly expressed endothel ial marker factor VIII. Matrigel based capillary-l ike tube formation assay showed that it could form endothel ial-l ike tube structures after 24 hours of culture. Conclusion Using improved method and ECM could obtain high quantity and high qual ity primary HUVECs, which might be a kind of promising seed cells for tissue engineering and precl inical research.