Changes of CD4+CD28- T cell and CD4+CD25+ regulatory T cell subsets in patients with coronary heart disease / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the changes of CD4(+)CD28(-) T cell and CD4(+)CD25(+) regulatory T cell (Treg) subsets in patients with coronary artery disease (CAD).</p><p><b>METHODS</b>Twenty-eight patients with angiographically established CAD were recruited in this study, including 16 with unstable angina (UA group) and 12 with stable angina (SA group). Eleven patients with chest pain syndrome served as the control group. The proportions of peripheral CD4(+)CD28(-) T cells and CD4(+)CD25(+) Treg subsets were determined with fluorescence-activated cell sorting (FACS).</p><p><b>RESULTS</b>The proportions of CD4(+)CD25(+) Treg were significantly lower in UA group (6.55-/+2.45%) than in SA (14.01-/+4.92%) and control groups (13.55-/+3.87%). The proportions of CD4(+)CD28(-) T cells were significantly higher in UA group (10.55-/+4.76%) than in SA (2.64-/+1.33%) and control (2.75-/+1.55%) groups.</p><p><b>CONCLUSION</b>Alterations of circulating T-lymphocyte subsets occur in patients with UA. The changes of Treg and CD4(+)CD28(-) T cells may lead to breakdown of peripheral autoimmune tolerance and play an important role in the development and progression of CHD.</p>

Effects of simvastatin on DNA synthesis in rat cardiac fibroblasts / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effects of simvastatin (Sim) and the interference by mevalonate (MVA) against its effect on DNA synthesis in rat cardiac fibroblasts (CFs).</p><p><b>METHODS</b>CFs were isolated from neonatal SD rats by trypsin digestion and growth-arrested CFs were stimulated with Sim and/or MVA at varied concentrations for different time lengths, and the DNA synthesis in the cells was measured by (3)H-thymidine ((3)H-TdR) incorporation assay.</p><p><b>RESULTS</b>Sim decreased (3)H-TdR incorporation in the CFs in a concentration-dependent manner, and (3)H-TdR incorporation was significantly lower in cells treated with 1 x 10(-6) and 1 x 10(-5) mol/L Sim (1,175+/-202.66 and 771+/-164.86 cpm/2000 cells, respectively) than in the control cells (1,608+/-204.32 cpm/2000 cells, P<0.01). As the treatment time with 1 x 10(-5) mol/L Sim prolonged (for 6, 12, 18, 24, 36, 42, and 48 h), (3)H-TdR incorporation in CFs decreased gradually, showing an obvious inverse correlation with the treatment time (r=-919, P<0.01). (3)H-TdR incorporation in cells treated with 1 x 10(-6) to 1 x 10(-3) mol/L MVA and 1 x 10(-5) mol/L Sim rose steadily as MVA concentration increased. A significant difference in the incorporation was found between cells treated with both 1 x 10(-4)/1 x 10(-3) mol/L MVA and 1 x 10(-5) mol/L Sim (1,612+/-308.57 and 1,995+/-353.83 cpm/2000 cells, respectively) and the cells with 1 x 10(-5) mol/L Sim treatment alone (P<0.01); difference was also noted between cells treated with 1 x 10(-5) mol/L MVA and the control cells (P<0.05), but treatment with 1 x 10(-6) mol/L MVA did not produce much difference in comparison with the control cells (P>0.05) With the increase of treatment time (for 6, 12, 18, 24, 36, 42, 48 h), 1 x 10(-3) mol/L MVA caused steady increase in (3)H-TdR incorporation in the CFs, showing a significant positive correlation with the treatment time (r=0.968, P<0.01).</p><p><b>CONCLUSION</b>Sim can decrease DNA synthesis in rat CFs and postpone the occurrence of myocardial fibrosis, which can be reversed by MVA.</p>