Objective To investigate the role of activation of Akt/mTOR pathway in denfense against UVB-induced apoptosis in cultured human skin keratinocyte cell line HaCaT. Methods HaCaT cells were irradiated with UVB at different doses for various durations. Western blotting was performed to detect dynamic changes of Akt/mTOR pathway-related signaling molecule, such as phosphorylated-epidermal growth factor receptor (EGFR), -Akt, -4EBP1, etc; apoptosis was estimated by staining with DNA dye Hoechst 33342. To evaluate the role of signaling molecules in defense against UVB-induced apoptosis, HaCaT cells were pretreated before irradiation with EGFR inhibitor (PD153035), PI3K inhibitor (LY294002), mTOR inhibitor (rapamycin) followed by the detection of expressions of signaling molecule and apoptosis. Results UVB could activate Akt/mTOR pathway in a dose- (5 ～ 30 mJ/cm2) and time- (5 ～ 30 min) dependent manner. PD153035,LY 294002 and rapamycin could inhibit UVB-induced activation of the Akt/mTOR pathway. The apoptosis rate in HaCaT cells was upregulated by pretreatment with rapamycin and LY294002. Conclusion The activation of Akt/mTOR signaling pathway could inhibit the UVB-induced apoptosis in cultured HaCaT cells.

Objective To observe the effect of dietary fat on diet-induced obesity in mice. Methods Forty 3-week.old male C57BL6 mice were randomly divided into four groups(1-4)fed withdiets of different amounts of lard [0%,20%,40%and 60%of total energy (kcal)].Plasma glucose,lipids,insulin and other parameters were measured after 7 weeks.Moreover,the livers and kidneys were taken for histopathological evaluation and white fatty tissues were taken to analyse adipose'associated geneexpressions using gene chip technology.Results There were statistically significant differences in weight, blood slucose.triglyceride,total cholesterol,high-density lipoprotein-cholesterol,low-density lipoprotein cholesterol.insulin and adiposity index between the 1st and the 4th group.Obvious lipid deposition in the liver and kidney sections was found in the 4th group.Thirteen adipose-associated genes were up-regulated in exDression and 8 genes down.regulated by over 2-fold in the adipocytes of the 4th group. Conclusions The mice fed with high-fat diet developed evident obesity,insulin resistance and abnormal lipid metabolism.The obesity was induced by high-fat diet via regulating some of the orexigenic genes,anorexigenie genes and the genes involved in energy expenditure in adipocytes of mice.

Objective To study the accuracy of real-time continuous monitoring system (RT-CGMS) at different stages and its association with glucose excursion. Methods Totally 33 patients with type 1 diabetes or type 2diabetes were under surveillance of RT-CGMS for 5 d. Capillary glucose values were measured 7 times daily.Correlation coefficient, error grid analysis (EGA), and Bland-Altman analysis methods were used to assess the correlation, accuracy and agreement of RT-CGMS at different stages and in general level; The mean amplitude of glucose excursion (MAGE) and the frequency of glucose excursion ( FGE ) were also calculated. Results ( 1 ) The correlation coefficient of RT-CGMS with capillary glucose values at fasting, postprandial stages, and in general level were 0.94,0.92, and 0.93 respectively( P＜0.01 ). (2) EGA showed that 98.82%, 98.39%, and 98.64% of the results fell in the A and B zones and 1. 18%, 1.61%, and 1.36% fell in the D zone respectively at fasting,postprandial stages, and in general level. There is no result fell in C and E zones. ( 3 ) The agreement analysis showed that RT-CGMS readings were in close agreement with capillary glucose values at fasting, postprandial periods, and in general level. (4)The MAGE at fasting, postprandial periods, and in general level were (3.57±2.66), (4.07±3.09), and (4. 02 ±3.04) mmol/L (P＞0. 05), (0±0. 5), (3± 1), and( 1 ±3) d for FGE (P＜0. 01 ).Conclusion RT-CGMS at fasting stage has higher accuracy than postprandial stage and general level, FGE at fasting stage is higher than postprandial stage and general level.

To determine the direct effect of leptin on adipose tissue apoptosis in vitro using rat adipose-derived stem cells (ADSCs), we isolated the ADSCs of rat epididymis adipose tissue by collagenase digestion, filtration, and subsequent centrifugation. Cell cultures with or without leptin (10(-9) mol/L, 10(-8) mol/L, 10(-7) mol/L and 10(-6) mol/L) were incubated for different time. We examined the cell surface phenotype by immunofluorescence and detected the apoptosis morphological changes of ADSCs by laser scanning confocal microscope (LCSM). The number of apoptotic cells was determined by flow cytometry assay after annexin V binding and PI staining. Caspase-3 activity was measured by spectrofluorometry. The present study demonstrates that leptin treatment causes a marked increase in adipose-derived stem cell apoptosis. With the LCSM, after being treated with leptin, ADSCs showed the typical characteristic of apoptosis. Leptin in used concentrations (0 mol/L, 10(-8) mol/L, 10(-7) mol/L, 10(-6) mol/L) caused a marked increase in cell apoptosis after 48 h incubation time (for 2.50% +/- 0.72%, 6.78% +/- 1.99%, 11.99% +/- 1.58% and 17.93% +/- 4.82%, respectively, P < 0.05). Caspase-3 activity increased and reached a maximal level after 48 h in a linear fashion. The effect of leptin was dose-dependent and time-dependent. Leptin has been demonstrated to induce preadipocyte and adipocyte apoptosis, and today we demonstrate that leptin can induce ADSCs apoptosis, which can contribute to the decrease of adiposity. To our knowledge, this is the first study demonstrating the direct peripheral effect of leptin on ADSCs.
Adipose Tissue ; cytology ; Animals ; Apoptosis ; drug effects ; Caspase 3 ; metabolism ; Cells, Cultured ; Epididymis ; cytology ; Leptin ; pharmacology ; Male ; Mesenchymal Stromal Cells ; cytology ; Rats ; Rats, Wistar

Objective To investigate the effect of segmental defects reconstruction of canine mandible with allogenenic bone marrow mesenchymal stem cells (BMSC) combined with lyophilized bone.Methods A 30 mm segmental defect was created on the left mandibles of beagles.Beagles were randomly divided into three groups.Allogeneic bone marrow mesenchymal stem cells with lyophilized bone were used for segmental defects reconstruction in group A.Autologous bone marrow mesenchymal stem cells with freeze-dried bone were used for segmental defects reconstruction in group B.The defects of group C were repaired with lyophilized bone only.Every three beagles were sacrificed 4, 12, 24, and 48 weeks after surgery respectively.The reconstruction effect was evaluated by CT and histopathological examination.Results CT examination showed that new bones formed in group A and group B 12 weeks after surgery, but not in group C.The form of the reconstructed mandibles in the three groups recovered in 48 weeks.The small pores on the bone graft were filled with new bones in group A and group B.In group C, the pores were still evident.Histopathological examination showed that bone trabecula between allogeneic bone and autogenous bone was completely joined in group A and group B.A large number of fibrous tissue appeared around the implanted bone and new bones were formed.In group C, the lyophilized bone resorption was still not obvious, the new bone formation was significantly slower than the other two groups.There was no difference between group A and group B.Conclusions Both allogeneic bone marrow mesenchymal stem cells and autologous mesenchymal stem cells could accelerate the bone formation.

Objective : To explore the clinical effect of personalized titanium mesh combined with free flap in the repair of maxillary defect. Methods: 36 cases of maxillary defect patients as the research object were selected in our hospital during May of 2010 to May of 2016. 36 defect cases were repaired with personalized titanium mesh combined with free flap, and summarize the treatment programs to explore the value of clinical application. Results : By the end of follow-up, all of the flap survived, tumor recurrence rate was 5.56% with paitient satisfaction was 100%; Diplopia and dysphagia occurred in no cases; Masticatory function declined accompanied with a longer chewing time but language communication was not affected. Conclusion The application of personalized titanium mesh and free flap repair methods in maxillary defect is significant, which effectively improve the quality of life of patients whereas still have difficulties in late denture at the same time.