ABSTRACT
Aim To study the effects of L-borneol on the chloride channel and cell volume of human umbili-cal vein endothelial cells (HUVECs). Methods Whole-cell patch-clamp technique was used to record chloride currents. The expression of ClC-3 protein was down-regulated by siRNA interference technique. The cell volume was measured by dynamic image analysis. Results 20 nmol·L-1L-borneol significantly activa-ted chloride current in HUVEC (79.59 ± 4.90) pA/pF, which could be inhibited by chloride channel blockers,NPPB and DIDS. The outward current inhib-itory rate of NPPB was (95.57 ± 2.57)%, while that of DIDS was (97.28 ± 6.36)%. The chloride current activated by L-borneol significantly decreased after the silence of ClC-3 (27.03 ± 3.89) pA/pF. Cell volume was markedly reduced by L-borneol (14.38 ± 1.58)%,which was inhibited after NPPB appliance. Conclusion L-borneol can activate ClC-3 chloride channel in HUVECs, which induces Cl- outflow then cell volume decrease.
ABSTRACT
Objectives: To explore the modulating effects and related mechanisms of p53-miR-34a-SIRT1 feedback loop in the process of replication senescence of vascular endothelial progenitor cells (EPC). Methods: EPC derived from umbilical cord blood were cultured and identified. Differences on senescence, cell apoptosis, cell cycle and blood tube formation were observed in EPC of 3rdand 6thgeneration. Protein expression of p53, Acetyl-p53, and SIRT1 was also detected by Western blotting in EPC of 3rdand 6thgeneration. The miR-34a inhibitor lentiviral vector was constructed and used to identify whether miR-34a inhibitor can protect 6thgeneration EPC from apoptosis. Results: EPC derived from umbilical cord blood were successfully cultured. The cells senescence rate and apoptosis rate of the 6thgeneration EPC were significantly higher than those of the 3rdgeneration EPC. The cell cycle of 6thgeneration EPC was mainly arrested at G0/G1 phase. The protein expression level of p53 was significantly higher, while the protein expression of acetyl-p53 and SIRT1 was significantly lower in the 6thgeneration EPC than in the 3rdgeneration EPC, all P<0.05. The senescence was significantly attenuated, and late apoptotic cells were significantly reduced, while angiogenesis ability was significantly enhanced in the 6thgeneration EPC transfected with lentiviral vector carrying miR-34a inhibitor. Conclusions: p53-miR-34a-SIRT1 is an important feedback mechanism in the process of EPC replication senescence. The miR-34a inhibitor may be the potential target of delaying EPC senescence.
ABSTRACT
AIM:To study the effect of ClC-3 gene over-expression on thyroid structure and function in mice. METHODS:Three-months-old FVB mice were used to study the difference of thyroid structure and function between wild-type(WT)mouse and ClC-3 transgene mice.The expression and distribution of ClC-3 in the thyroid of mice were deter-mined by the methods of qPCR,Western blot and immunofluorescence.Behavioral monitoring was performed on the daily activities of mice.Serum concentrations of total triiodothyronine(TT3), total thyroxine(TT4)and thyrotropin(TSH) were measured by ELISA.RESULTS:Compared with the WT group,the expression of ClC-3 in the thyroid of ClC-3 trans-gene group was significantly increased(P<0.05).The thyroid gland showed obvious hyperplasia and the folliculi glandu-lae thyreoideae was significantly bigger in ClC-3 transgene mice(P<0.05).The weight loss was increased in ClC-3 trans-gene mice(P<0.05).The expression of TT3 and TT4 were significantly higher than that of WT group(P<0.05),but the change of TSH was not obvious.CONCLUSION:ClC-3 over-expression results in thyroid hyperplasia and thyroid hor-mone secretion.This study suggests that ClC-3 is likely to be involved in the synthesis of thyroid hormones.
ABSTRACT
The aim of this study was to investigate the relationship between the acetylcholine concentration in the blood and gelsenicine-induced death in mice. Kunming mice were given intraperitoneal injections of normal saline, gelsenicine or different doses of acetylcholine chloride. Atropine was given to the mice which received gelsenicine or medium dose acetylcholine chloride injection. The blood was sampled immediately when the mice died or survived for 20 min after injection. The acetylcholine concentration and acetylcholinesterase activity in the blood were measured by the testing kits, and the mortality was calculated and analyzed. The results showed that half lethal dose of gelsenicine (0.15 mg/kg) reduced the acetylcholinesterase activity and increased the blood acetylcholine concentration. The blood acetylcholine concentration of the dead mice in the gelsenicine group was increased to 43.0 μg/mL (from 31.1 μg/mL in the control), which was lower than that (53.9 μg/mL) of the dead mice in the medium dose acetylcholine chloride group, but almost equal to that (42.7 μg/mL) of the survival mice in the medium dose acetylcholine chloride group. Atropine could successfully rescue the mice from acetylcholine poisoning, but its efficiency of rescuing the mice from gelsenicine intoxication was weak. These results suggest that gelsenicine can inhibit acetylcholinesterase activity and increase blood acetylcholine concentration, but the accumulation of acetylcholine may not be the only or main cause of the death induced by gelsenicine in mice.