Effects of curcumin on sarcoplasmic reticulum Ca2+-ATPase in rabbits with heart failure / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the effects of curcumin on sarcoplasmic reticulum Ca2+-ATPase in heart failure rabbits.</p><p><b>METHODS</b>Rabbit heart failure model was made with aortic regurgitation and abdominal aorta constriction and 40 rabbits were randomly divided into 4 groups including: (1) heart failure treated with curcumin; (2) heart failure treated with placebo; (3) healthy control treated with curcumin and (4) healthy control treated with placebo. All rabbits were administrated with curcumin capsules or placebo capsules 100 mg x kg(-1) x d(-1), respectively. All groups were sacrificed after eight weeks. Myocardial ultrastructural organization was detected by transmission electron microscope. RT-PCR and Western blot were used to measure the expression of sarcoplasmic reticulum Ca2+-ATPase in mRNA and protein levels, respectively. Malachite green colorimetric assay was used to evaluate the activity of sarcoplasmic reticulum Ca2+-ATPase.</p><p><b>RESULTS</b>All detected parameters were similar between control curcumin group and control placebo group. Compared with the control groups (Groups 3 and 4), the heart/body weight ratio was significantly increased in the heart failure-curcumin group (Group 1) and the heart failure-placebo group (Group 2, all P < 0.05), but the ratio was significantly lower in heart failure-curcumin group than in heart failure-placebo group (P < 0.05). The degree of heart failure was decreased by curcumin. Activity and mRNA and protein expression for sarcoplasmic reticulum Ca2+-ATPase were significantly reduced in the heart failure-placebo group and which could be significantly attenuated by curcumin (all P < 0.05).</p><p><b>CONCLUSION</b>Curcumin could improve cardiac function via upregulating the expression of sarcoplasmic reticulum Ca2+-ATPase in this model.</p>

Magnetic resonance signal detection of superparamagnetic iron oxide nanoparticles and its biological effects on endothelial cells / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the magnetic resonance (MR) signal changes of superparamagnetic iron oxide (SPIO) and its biological effects on endothelial cells.</p><p><b>METHODS</b>The citric-acid coated SPIO was synthesized by co-precipitation method. The human umbilical vein endothelial cells (HUVECs) were incubated with SPIO for 24 h in culture medium at iron concentration of 0.01, 0.05, 0.10, 0.15 mg/ml (experimental groups), and the cells incubated without SPIO served as control groups. The uptake efficiency of intracellular iron was measured by Prussian blue staining, and the cell viability was monitored by Calcein-AM method. The cell cytoskeleton (F-actin and tubulin), adherence and migration capacity were measured by immunofluorescence staining. The iron oxide nanoparticles distribution and the cellular organelle change were monitored by transmission electron microscopy (TEM). Quantification of particle uptake was measured by atomic absorption spectrometry. The MR signal of endothelial cells after labeling was monitored by Philips 3.0 T MR scanner.</p><p><b>RESULTS</b>SPIO was uptaken by HUVECs in a concentration-dependence manner. Compared with the control group, cell viability was decreased along with the increase of iron concentration. Compared with the control group, the cell cytoskeleton was markedly disorganized and the FAK spot was bigger and sparser.The nanoparticles were mainly existed in lysosomes, and the higher concentration of SPIO, the more lysosomes and vacuoles presented in the cells. The iron content per cell was (55.86 +/-9.935) pg when the SPIO concentration was 0.15 mg/ml. The MR image showed that the cells labeled with SPIO resulted in the decrease of MR signal.</p><p><b>CONCLUSION</b>The cells labeled with SPIO can be detected by MR. The cell viability, cytoskeleton, adherence and migration capacity of HUVECs are affected by citric-acid coated SPIO in a concentration-dependent manner.</p>