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@#【Objective】Platelet hyper- reactivity plays an important role in thrombosis and cardiovascular diseases. As a dietary supplement，Fruitflow，a water-soluble tomato concentrate，plays an important role in preventing cardiovascular diseases，but the mechanisms have been poorly understood，and there is no direct evidence about the effect of Fruitflow on thrombosis. This study intends to explore the effects of Fruitflow on platelet aggregation，activation and thrombosis in healthy people，and explore its possible mechanism.【Methods】Platelets from healthy men and women were incubated with different concentrations（0，20，40，80 mg/L）of Fruitflow，and the platelet aggregation was measured by platelet aggregometer. Platelet αIIbβ3 activation and fibrinogen binding to the activated platelets was measured by flow cytometry. The thrombosis in FeCl3- induced mesenteric artery thrombosis model in mice was observed by stereoscopic fluorescence microscope. The bleeding time was measured by tail clipping in mice. The total and phosphorylation levels of platelet Akt， Erk1/2 and JNK were determined by Western blotting.【Results】After the stimulation of ADP，Fruitflow could significantly attenuate platelet aggregation in the dose of 20，40，80 mg/L. Compared with that in the control group（43.75±5.91）%， platelet aggregation in the 80 mg/L group decreased to（8.25 ± 4.57）%（P < 0.000 1）. Fruitflow also inhibited the activation of platelet αIIbβ3. Compared with that in the control group（79.36±6.26），the platelet αIIbβ3 in the 80 mg/L group decreased to（65.79±5.73，P < 0.01）. Fruitflow reduced the platelet fibrinogen binding to the activated platelets. Compared with that in the control group（69.34 ± 6.63），platelet fibrinogen binding to the activated platelets in the 80 mg/L group decreased to（56.70±8.86，P < 0.05）. Fruitflow attenuated the thrombosis in FeCl3-induced mesenteric artery thrombosis model. Compared with that in the control group（22.50±4.86），the vessel occlusion in the 80 mg/L group was extended to（39.20 ± 4.61，P < 0.01）. There was no statistical difference between the control group （5.95 ± 0.69） and the 80 mg/L group（5.74 ± 0.76）in bleeding time（P > 0.05）. Fruitflow down- regulated the phosphorylation levels of platelet Akt， Erk1/2 and JNK proteins. Compared with the control group，P- Akt/Akt decreased from 0.97 ± 0.07 to 0.33 ± 0.13（P <0.001），P-Erk1/2/Erk1/2 decreased from 0.89±0.09 to 0.24±0.02（P < 0.01），and P-JNK/JNK decreased from 0.97±0.12 to 0.45±0.04（P < 0.01）in the 80 mg/L group.【Conclusion】Inhibition of platelet PI3K/Akt and MAPKs signaling pathway may be one of the mechanisms that Fruitflow inhibits platelet aggregation ，activation and thrombosis.
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BACKGROUND: Mitogen-activated protein kinase signaling pathway participates in the differentiation of osteoblasts and osteoclasts, closely related to subchondral bone reconstruction and play a key role in the occurrence and development of osteoarthritis. Bisphosphonates as bone resorption inhibitor is used to treat osteoporosis. OBJECTIVE: To observe the effect of sodium ibandronate on the knee osteoarthritis in rats, and changes of mitogen-activated protein kinase signaling pathway. METHODS: The study was approved by the Laboratory Animal Ethical Committee of the First Affiliated Hospital of South China University. Thirty female Sprague-Dawley rats were randomly divided into sham, model, and treatment groups. The rats in the latter two groups underwent ovariectomy bilaterally, and anterior cruciate ligament resection, and rats in the sham group received the fatty tissue surrounding the ovaries removed only. After 1 week of surgery, the rats in the treatment group were given intraperitoneal injection of 10 pg/kg sodium ibandronate, rats in the model group were injected with normal saline, and the sham group received no intervention. Twelve weeks late, the rats were killed to perform histological examination of cartticular cartilage and Mankin scores were detected. Micro-CT of subchondral bone and quantitative analysis of the bone microstructure were conducted. The protein and mRNA expression levels of extracellular signal regulated protein kinase and c-Jun N-terminal kinase in mitogen-activated protein kinase signaling pathway were measured. RESULTS AND CONCLUSION: (1) The cartilage structure in the model group was significantly damaged, the Mankin score was significantly higher than that in the sham group, and the Mankin score in the treatment group was significantly lower than that in the model group (P < 0.01). (2) The bone mineral density, trabecular bone volume ratio, trabecular number in the model group were significantly lower than those in the sham group (P < 0.01), and trabecular separation was higher than that in the sham group (P < 0.01). Compared with the model group, the treatment group had higher bone mineral density, trabecular bone volume ratio, trabecular number, and lower trabecular separation (P < 0.01). (3) The mRNA and protein expression levels of extracellular signal regulated protein kinase and c-Jun N-terminal kinase in the model group were significantly higher than those in the sham group (P < 0.05, P < 0.01), and the levels in the treatment group were significantly lower than those in the model group (P < 0.05). (4) To conclude, sodium ibandronate may inhibit subchondral bone loss and articular cartilage degeneration in rat models of osteoarthritis by inhibiting extracellular signal regulated protein kinase and c-Jun N-terminal kinase in mitogen-activated protein kinase signaling pathway.
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OBJECTIVE： To investigate inhibitory effects of lupeol on the proliferation of human breast cancer MCF-7 cells and its possible mechanism. METHODS： Taking MCF-7 cells as research object， MTT assay was used to detect the proliferation of MCF-7 cells after treated with different doses of lupeol （7.5， 15， 30， 60， 90 mg/L） for 24 h. Survival rate and IC50 of MCF-7 cells were calculated. The inverted microscope and cell cloning experiment were used to observe and detect the morphological characteristics of MCF-7 cells and clonal colony formation after treated with different doses of lupeol （15， 30， 60 mg/L） for 24 h. The rate of clonal colony formation was calculated. MTT method and Western blotting assay were used to detect the proliferation of MCF-7 cells and the expression of related regulatory proteins （ERK1/2， p-ERK1/2， JNK， p-JNK， p38 MAPK， p-p38 MAPK） after additionally treated with MAPKs signaling pathway-related regulation protein inhibitors PD98059， SP600125 and SB203580. RESULTS： After treated with 15， 30， 60， 90 mg/L lupeol， survival rates of MCF-7 cells were decreased significantly （P＜0.05 or P＜0.01）. IC50 value of the compound was 52.94 mg/L. After treated with 15， 30， 60 mg/L lupeol， the morphological characteristics of cells in each group changed， and the phenomena of cell exfoliation， floating， solid shrinkage， roundness， volume reduction and necrosis were observed. The formation of clonal colony decreased and the rate of clonal colony formation decreased significantly （P＜0.05 or P＜0.01）. When lupeol used alone， compared with control group， survival rate （60 mg/L lupeol）of MCF-7 cells was decreased significantly； the expression of p-ERK1/2 （15， 30， 60 mg/L lupeol）， p-JNK （30， 60 mg/L lupeol） and p-p38 MAPK （30， 60 mg/L lupeol） were increased significantly （P＜0.05 or P＜0.01）. After additional use of relevant inhibitors， compared with 60 mg/L lupeol group， survival rates of MCF-7 cells in combination groups were increased significantly， while relative expression of p-ERK1/2， p-JNK and p-p38 MAPK were decreased significantly （P＜0.05 or P＜0.01）. CONCLUSIONS： Lupeol can inhibit the proliferation of human breast cancer MCF-7 cells， the mechanism of which may be related to the phosphorylation of MAPKs signaling pathway-related regulatory proteins.
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<p><b>OBJECTIVE</b>To investigate the effect of aloin on apoptosis of human gastric cancer cells and explore the molecular mechanism.</p><p><b>METHODS</b>Gastric cancer MKN-28 and HGC-27 cells were cultured routinely in 1640 medium supplemented with 10% fetal bovine serum and 10% non-essential amino acids (for HGC-27 cells) and treated with different concentrations of aloin for different durations. The cell viability, cell nuclear morphology, and apoptotic rate of the cells were detected using CCK-8 assay, DAPI staining and AnnexinV-FITC/PI, respectively; Western blotting was used to detect the expression levels of PARP, procaspase 3 and the phosphorylation of p38, ERK and JNK. The cells were treated with specific inhibitors of p38, ERK and JNK, and the inhibitory effects on these pathways were detected with Western blotting; DAPI staining was used to detect the effects of inhibitors on apoptosis of gastric cancer cells.</p><p><b>RESULTS</b>Aloin dose-dependently inhibited the viability and induced apoptosis of HGC-27 and MKN-28 cells. Alion treatment obvious enhanced the phosphorylation of p38 and JNK but decreased ERK phosphorylation in the cells. Blocking ERK activation with the ERK inhibitor obviously enhanced aloin-induced cell apoptosis, where inhibiting p38 and JNK activation partly reversed alion-induced apoptosis in the cells.</p><p><b>CONCLUSIONS</b>Aloin induces apoptosis of human gastric cancer cells by activating p38 and JNK signaling pathways and inhibiting ERK signaling pathway.</p>
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Objective:To study the role of TOLL-like receptor4/MAPKs pathway of renal tissue in the diabetic rats treated with piogitazone. Methods:The male Sprague Dawlry rats were randomly selected as the control group (n=8) and experimental group(n=32). The experimental rats were randomly divided into three groups. The expression of ERK1/2,JNK and p38MAPK,and levels of their phosphorylation in kidney were measured by Western blot in control group and experimental group. Results:The expression of TOLL-like receptor 4 in all renal tissue in the diabetic rats were significantlyincreased than those in control group (P<0. 01). Compared with the control group. The activity of p-ERK1/2 and p38MAPK significantly increased in each experimental group (P<0. 05),but the expression level of p-JNK was no statistical significance. TOLL-like receptor 4 could regulatory effect on the phorylation of ERK1/2 and p38MAPK. Compared with the model group,the expression of p-ERK1/2 and p38MAPK significantly decreased(P<0. 05),moreover, these changes were more significant in high-dose treated group ( P<0. 05 ) . Conclusion:Pioglitazone inhibits the expression of TOLL-like receptor 4 of renal tissue in the diabetic rats,and these effects may be related to TOLL-like receptor 4/ERK1/2 and TOLL-like receptor 4/p38MAPK pathways.