ABSTRACT
OBJECTIVE To investigate the effect of prenatal nicotine exposure on cardiac ejection function and myocardial fibrosis of the offspring of rats.METHODS Pregnant rats were sc given nicotine 6.0 mg· kg-1,once daily for 17 d.The body mass and heart mass of the offspring were detected at the 21th day of gestation,and 15 and 90 d after birth.Heart rate of 90 d offspring was recorded by ECG,and cardiac functions were detected by Doppler ultrasonography,including cardiac output (CO),stroke volume (SV),ejection fraction (EF),left ventricular long axis shortening fraction (FS),interventricular septum diastolic diameter (IVSd) and left ventricular posterior wall diastolic diameter (LVPWd).The myocardial ultrastructure was detected under an electron microscope.Masson staining was used to detect the myocardial collagen fiber deposition.The level of collagen protein type Ⅰ in heart tissue was detected by radioimmunoassay.RESULTS Compared with control group,prenatal nicotine exposure resulted in a decrease of heart mass and body mass in groups of 21 d fetal rats and 15 d offspring(P＜0.05,P＜0.01),but had no effect on the 90 d offspring.Compared with the normal control group,the heart rate of 90 d offspring increased [366+10 vs (418+10) min-1] (P＜0.05),CO,FS and EF decreased (P＜0.01),and IVSd and LVPWd increased (P＜0.05,P＜0.01).Electron microscopy revealed that in the heart of nicotine 90 d offspring,myocardial fiber arrangement was loosened and confused,while extracellular matrix increased.Masson staining showed collagen deposited in the myocardium.The level of collagen type Ⅰ in heart tissue increased [0.59±0.09 vs (0.40±0.05) tμg·g-1 tissue] (P＜0.01).CONCLUSION Prenatal nicotine exposure induces the increased level of cardiac collagen type Ⅰ,myocardial fibrosis and decrease of cardiac ejection function in adult offspring,which may lead to increased susceptibility to cardiovascular diseases.
ABSTRACT
Objective To investigate the inhibitory effect of curcumin on the telomerase activity of HeLa cells.Methods The growth inhibition rate of HeLa cells treated with curcumin was measured with MTT method.The expression of hTERT mRNA was studied using RT-PCR.Telomerse activity was examined by TRAP-ELISA.Results The growth of HeLa cells treated with curcumin was inhibited in concentration dependent manner and the expression of hTERT mRNA and the level of telomerase activity were down-regulated significantly.Conclusion Curcumin can inhibit telomerase activity of HeLa cells.The underlying mechanism might be related to the down-regulation of hTERT transcription.
ABSTRACT
Caveolin-1(Cav-1) is a scaffold protein of caveolae that acts as a tumor modulator by interacting with cell adhesion molecules and signaling receptors.Evidence from a variety of studies indicate that caveolin-1 exhibits the heterogeneity of Cav-1 expression in different tumors.Current research has clearly established a role for Cav-1 as a a novel prognostic marker,Future studies will undoubtedly offer novel exciting opportunities to develop anti-cancer therapies.