These results provide evidence that HMG-CoA reductase inhibitors are potent and effective cardioprotective agents that inhibit leukocyte-endothelial cell interactions and preserve cardiac contractile function and coronary perfusion after myocardial ischemia and reperfusion. Moreover, these effects are unrelated to the cholesterol-lowering action of this agent and appear to be mediated by enhanced endothelial release of NO.

Peroxynitrite (ONOO Ϫ ) anion, formed by the interaction of superoxide with nitric oxide (NO), has previously been implicated as a cytotoxic agent. However, the effects of this free radical species on neutrophil (PMN)-endothelial cell interactions is largely unknown. We investigated the direct actions of ONOO Ϫ on PMN adhesion to endothelial cells in vitro and in vivo, as well as the effects of ONOO Ϫ on PMNmediated myocardial ischemia-reperfusion injury. In vitro, peroxynitrite (100-1,000 nM) inhibited the adhesion of rat PMNs to the endothelium of isolated thrombin-or H 2 O 2 -stimulated rat mesenteric artery ( P Ͻ 0.01 vs. thrombin or H 2 O 2 alone). In vivo, in the rat mesentery, thrombin (0.5 U/ ml) or N G -nitro-L -arginine-methyl ester (50 M) significantly increased venular leukocyte rolling and adherence, which were also significantly ( P Ͻ 0.01) attenuated by ONOO Ϫ (800 nM) accompanied by reduced P-selectin expression on the endothelial cell surface. Isolated perfused rat hearts were subjected to global ischemia and reperfusion with rat PMNs (10 8 cells), which resulted in profound cardiac depression (i.e., a marked reduction in left ventricular developed pressure and maximal rate of development of left ventricular pressure). Infusion of ONOO Ϫ reversed the myocardial contractile dysfunction of ischemic-reperfused rat hearts to near baseline levels, and markedly attenuated the accumulation of PMNs in the postischemic heart. The present study provides strong evidence that nanomolar concentrations of ONOO Ϫ both inhibit leukocyte-endothelial cell interactions and exert cytoprotective effects in myocardial ischemia-reperfusion injury. Furthermore, our results suggest that the inhibition of P-selectin expression by peroxynitrite is a key mechanism of the modulatory actions of ONOO Ϫ on leukocyte-endothelial cell interactions.

Doxorubicin (Dox) is a highly effective antineoplastic antibiotic associated with a dose-limiting cardiotoxicity that may result in irreversible cardiomyopathy and heart failure. The purpose of this study was to examine the effects of low-intensity exercise training (LIET) during the course of Dox treatment on cardiac function, myosin heavy chain expression, oxidative stress, and apoptosis activation following treatment. Male Sprague-Dawley rats either remained sedentary or were exercise trained on a motorized treadmill at 15 m/min, 20 min/day, 5 days/wk (Monday through Friday) for 2 wk. During the same 2-wk period, Dox (2.5 mg/kg) or saline was administered intraperitoneally to sedentary and exercised rats 3 days/wk (Monday, Wednesday, Friday) 1-2 h following the exercise training sessions (cumulative Dox dose: 15 mg/kg). Five days following the final injections, hearts were isolated for determination of left ventricular (LV) function, lipid peroxidation, antioxidant enzyme protein expression, 72-kDa heat shock protein expression, caspase-3 activity, and myosin heavy chain isoform expression. Dox treatment significantly impaired LV function and increased caspase-3 activity in sedentary animals (P < 0.05). LIET attenuated the LV dysfunction and apoptotic signal activation induced by Dox treatment and increased glutathione peroxidase expression, but it had no significant effect on lipid peroxidation, protein expression of myosin heavy chain isoforms, 72-kDa heat shock protein, or superoxide dismutase isoforms. In conclusion, our data suggest that LIET applied during chronic Dox treatment protects against cardiac dysfunction following treatment, possibly by enhancing antioxidant defenses and inhibiting apoptosis.

The technology of building an expert system for diagnosing malignant nature of invasive tumors of the mammary gland based on a set of quantitative features of the cell nuclei has been developed. Its peculiarity was the presence of weighting coefficients in all the features. Quantitative features were obtained by transforming the initial morphometric data with the help of simple (evaluation of mean values and building of histograms) and complex (regression analysis) mathematical operations. The expert system consisted of one‐dimensional X‐matrix used for investigations and two‐dimensional standard S‐matrix. The X‐matrix elements were assigned for filling with the quantitative features of the studied sample with a nonestablished diagnosis. The S‐matrix elements contained threshold values of quantitative features from the system of diagnostic decision criteria for malignant forms of diseases and their weighting coefficients. Threshold values of nuclear features (larger or smaller) were determined taking into account the range of their values in the groups of malignant and benign pathology. Significance of quantitative features in diagnosing diseases has been assessed. The presence of weighting coefficients allowed diagnosing malignant and benign pathology in a quantitative form by the diagnostic index value. Diagnostic index was calculated by the sum of weighting coefficients of features of the studied sample, which fell within the range of system of the S‐matrix diagnostic decision criteria. Clinical trials revealed high efficiency of the developed approach while diagnosis of breast cancer invasive forms at a preoperative stage. Diagn. Cytopathol. 2013. © 2012 Wiley Periodicals, Inc.

Endurance training prior to DOX treatment protects against acute DOX cardiotoxicity for up to 10 d, and this protection can potentially be explained by a preservation of MHC isoform distribution.

The clinical use of doxorubicin (DOX) is limited by a dose-dependent cardiotoxicity. The purpose of this study was to determine whether voluntary exercise training would confer protection against DOX cardiotoxicity in the isolated perfused rat heart. Female Sprague-Dawley rats were randomly assigned to standard holding cages or cages with running wheels for 8 wk. Twenty-four hours after the sedentary (SED) or voluntary exercise (VEX) running period, rats were anesthetized with pentobarbital sodium, and hearts were isolated and perfused with oxygenated Krebs-Henseleit (KH) buffer at a constant flow of 15 ml/min. After a 20-min stabilization period, hearts were paced at 300 beats per minute and perfused with KH buffer containing 10 microM DOX for 60 min. A set of control hearts from SED and VEX rats were perfused under identical conditions without DOX for the same period. DOX perfusion led to significant decreases in left ventricular developed pressure, +dP/dt, and -dP/dt, and significant increases in LV lipid peroxidation in sedentary rats compared with non-DOX controls (P < 0.05). Prior voluntary exercise training attenuated these DOX-induced effects and was associated with a significant increase (78%, P < 0.05) in heat shock protein (HSP72), but not mitochondrial isoform of SOD (MnSOD) or CuZnSOD protein expression in the hearts of wheel-run animals. These data indicate that chronic physical activity may provide resistance against the cardiac dysfunction and oxidative damage associated with DOX exposure and provide novel evidence of HSP72 induction in the heart after voluntary exercise.

These data suggest that physiologically relevant concentrations of ONOO- exert significant cardioprotective and vasculoprotective effects in MI/R in cats, at least partially by attenuating PMN-endothelium interactions.

These data suggest that the cardioprotective effects of exercise against DOX-induced injury may be due, in part, to a reduction in myocardial DOX accumulation.