ABSTRACT
@#Time series model was developed to investigate the effect and contributions of related biomarkers on the cerebral endothelial dysfunction induced by beta amyloid(Aβ). HCMEC/D3 was incubated with 2. 5 μmol/L Aβ for 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22 and 24 h, and biomarkers including cytosolic calcium ion, mitochondrial membrane potential(MMP), endothelial nitric oxide synthase(eNOS)and cell viability were determined. Time series model was established to assess the dynamic relationship between the related biomarkers and cell viability and the contribution of different biomarkers to cell damage. Impulse response analysis indicated that after a positive impact on cytosolic calcium ion, cell viability decreased and this impact continued to decline; after a positive impact on endothelial nitric oxide synthase and mitochondrial membrane potential, cell viability increases, which increased rapidly in the early stage, and the rate decreased in later stage. The result of variance decomposition showed that the cytosolic calcium ion played a major role in cerebral endothelial dysfunction induced by Aβ. Combined with the model study, it is concluded that the intervention on the level of cytosolic calcium ion at the early stage may be the possible way to slow the disease progression.
ABSTRACT
Objective: To observe the influence of TRPV6 gene silence on SW480 colon cancer cell biological behavior, change in the in-tracellular concentration of calcium, as well as influence of 1,25 (OH)2D3CaCl2and CuCl2on SD rat colonic neoplasm models. Method: SW480 colon cancer cells were infected using lentivirus particles. TRPV6 protein and mRNA expression was detected using immunohistochemical tests, Western blot, and PCR. Moreover, the proliferation, metastasis, and apoptosis of SW480 colon cancer cells were detected through MTT assay and metastasis and apoptosis experiments, and the concentration of Ca2+in SW480 colon cancer cells was measured using high-speed ionic imaging. The SD rat colon cancer model was established based on DMH, and were assigned into experimental group (DMH group, 15) and intervention group (DMH+1,25 (OH)2D3group, DMH+CuCl2group) and control group, 10 in each group. The SD rat colon cancer model is established based on DMH, given 1,25(OH)2D3(37.5 nmol/kg) and CuCl2(375 μmol/kg) separately as intervention. The occurrence of colonic neoplasms and glandular cancers in each group of rats was observed, and Western blot was employed for detection of the TRPV6 protein expression. Results: After the transfection of SW480 colon cancer cells by TRPV6-RNAi, the expression of TRPV6 mRNA and protein decreased, intracellular concentration of Ca2+decreased, proliferation and metastasis rate of SW480 colon cancer cells decreased, and apoptosis rate of these cells increased. The differences between the groups with intervention and the blank control group and negative control group showed statistical significance (P<0.05). The colon cancer occurrence rate in the control group was 0, while that of the DMH+1,25 (OH)2D3 group, DMH group, and DMH+CuCl2were 100%, 84.62%, and 33.33%, respectively. The TRPV6 protein expression was detected in all groups, while DMH+1,25(OH)2D3group was observed to exhibit the highest level of expression, followed by the DMH group, DMH+CuCl2group, and control group. The differences were of statistical significance (P<0.05). Conclusions: The proliferation and metastasis of SW480 colon cancer cells can be prohibited by lowering the concentration of Ca2+in the cells. Thus, the apoptosis of the cells can be induced. 1,25 (OH)2D3can help improve the expression of TRPV6 protein in experimental rat colon tissues and promote the formation of colon neoplasms. CuCl2can help lower the expression of TRPV6 protein in experimental rat colon tissues and prevent the formation of colon neoplasms.
ABSTRACT
AIM:To observe the effects of granulocyte colony-stimulating factor (G-CSF) on calcium, sodium and potassium ion channel currents of the ischemic atrial myocytes in guinea pig by whole-cell patch clamp technique.METHODS:The guinea pig atrial myocytes were obtained by enzymolysis.Under ischemia and hypoxia condition, whole-cell patch clamp was used to observe the effects of G-CSF at various concentrations on the changes of the I-V curve, activation curve and availability of L-type calcium channel current (ICa,L) and voltage-dependent sodium channel current (INa), as well as I-V curve of delayed rectifier potassium channel current (IK).RESULTS:Under ischemic condition, the I-V curves of ICa,L were changed by acute G-CSF intervention in a dose-dependent fashion.Except for G-CSF at dose of 300 μg/kg, the other concentrations of G-CSF did not change the activation curve and availability of ICa,L, indicating that the effects of G-CSF on ICa,L were in a voltage-independent fashion.The I-V curves of ICa,L under ischemic condition were gradually approaching the normal levels by the higher dose of G-CSF, while the effect of 300 μg/kg G-CSF on ICa,L was similar to 100 μg/kg G-CSF.Acute G-CSF intervention at different doses did not change I-V curve, activation curve, and availability or steady-state availability of INa.As a part of IK, the rapid activating component (IKr) was improved by 100 μg/kg and 300 μg/kg G-CSF intervention with the similar effects, while the slowly activating component (IKs) was not changed by G-CSF.CONCLUSION:G-CSF affects ion channel electrophysiological properties of ischemic atrial myocytes in a voltage-independent but concentration-dependent manner, thus reducing the incidence of atrial arrhythmia.