GRK 2 level in peripheral blood lymphocytes of elderly patients with acute myocardial infarction

Objective To investigate the G protein-coupled receptor kinase 2 (GRK 2) level in peripheral blood lymphocytes with cardiac func-tion in elderly patients with acute myocardial infarction. Methods This study enrolled 40 patients with acute ST-segment elevation myo-cardial infarction (STEMI) and 40 patients with unstable angina. All patients were 65 years or older. Cardiac function was evaluated by echocardiography, and the GRK 2 level in peripheral blood lymphocytes was measured. Patients with STEMI were followed up for 2 years. Results The GRK 2 level in peripheral blood lymphocytes was significantly higher in patients with STEMI than in patients with unstable angina, and was negatively correlated with left ventricular ejection fraction, cardiac output, stroke volume, and left ventricular fractional shortening. The GRK 2 level was significantly elevated in some patients with acute STEMI and poor cardiac function. Conclusions In-creased GRK 2 level in patients with acute STEMI may contribute to poor myocardial systolic function and myocardial remodeling. Meas-urement of the GRK 2 level in peripheral blood lymphocytes may assist in the evaluation of cardiac function and myocardial remodeling in elderly patients with acute STEMI.

Effect of Atorvastatin on Expression of Peroxisome Proliferator-activated Receptor Beta/delta in Angiotensin Ⅱ-induced Hypertrophic Myocardial Cells In Vitro

Objective To explore the effect of atorvastatin on cardiac hypertrophy and to determine the potential mechanism involved. Methods An in vitro cardiomyocyte hypertrophy from neonatal rats was induced with angiotensinⅡ(Ang Ⅱ) stimulation. Before AngⅡ stimulation, the cultured rat cardiac myocytes were pretreated with atorvastatin at different concentrations(0.1, 1, and 10 μmol/L). The following parameters were evaluated: the myocyte surface area, 3H-leucine incorporation into myocytes, m RNA expressions of atrial natriuretic peptide, brain natriuretic peptide, matrix metalloproteinase 9, matrix metalloproteinase 2, and interleukin-1β, m RNA and protein expressions of the δ/β peroxisome proliferator-activated receptor(PPAR) subtypes. Results It was shown that atorvastatin could ameliorate Ang Ⅱ-induced neonatal cardiomyocyte hypertrophy in the area of cardiomyocytes, 3H-leucine incorporation, and the expression of atrial natriuretic peptide and brain natriuretic peptide markedly. Meanwhile, atorvastatin also inhibited the augmented m RNA level of several cytokines in hypertrophic myocytes. Furthermore, the down-regulated expression of PPAR-δ/β at both the m RNA and protein levels in hypertrophic myocytes could be significantly reversed by atorvastatin treatment. Conclusions Atorvastatin could improve AngⅡ-induced cardiac hypertrophy and inhibit the expression of cytokines. Such effect might be partly achieved through activation of the PPAR-δ/β pathway.

Effects of neuro-immuno-modulation on healing of wound combined with local radiation injury in rats

Purpose： To investigate effects of neuro-immuno-modulation on wound healing by observing changes of cytokines and hypothalamic-pituitary-adrenal （HPA） axis hormones in acute stress reaction in rats with wound and combined local radiation injury. Methods： Sixty female Wistar rats （weighting 200 ± 20 g） were randomly divided into normal control group, wound group and combined wound-local radiation （CWR） group （25 Gy local radiation post wound）, 20 rats in each group. Contents of IL-1β, IL-6 and IFN-γ and IL-4 in serum were measured and changes of adrenocorticotropic hormone （ACTH） and glucocorticoid （GC） in serum were analyzed by using enzyme-linked immunosorbent assay and radioimmunologic assay, respectively at different time points post wound and radiation. Results： （1） The level of IFN-γ, one of the Thl cell cytokines increased significantly at 14 d post CWIL which was markedly higher than that in control group and wound group. However, the level of IL-4, IL-1β and IL-6, one of the Th2 cell cytokines, did not show obvious change. （2） Ratio of Thl/Th2 （IFN-γ/IL-4） in wound group and CWR group increased significantly at 7 d after wound and radiation, which suggested that Thl/Th2 balance drifted to Thl immune response. The ratio of Thl/Th2 in wound group returned to the normal level up to 14 d after the wound and radiation, while the Thl/Th2 ratio in CWR group increased persistently and was much higher than that in control and wound groups. （3） Level of serous ACTH and CC in CWR group increased at 3 d post wound and radiation, and among them, level of CC showed statistically significant increase, which was much higher than that in control and wound groups. Conclusion： Level of serous neurohormone CC in rats increased significantly immediately after wound and radiation; while the level of IFN-γ showed significant increase only up to 14 d after wound and radiation, and the Th1/Th2 imbalance sustained till 28 d post wound and radiation. In order to reduce acute damage caused by CWR, organic immune system and nerve system showed up a marked regulate effects simultaneously and mutually. Nonetheless, the excessive stress induced by CWR causes distur- bance of immunoregulation, which is one of the key reasons for delayed wound healing in CWR.