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This study aims to investigate the influence of excessive oxidative stress on cardiac injury during acute myocardial ischemia (AMI), with a focus on apoptosis, autophagy, and inflammatory cell infiltration, and to detect the role of hydrogen sulfide (H2S) in this process. We found that SOD1 knockout (KO) mice showed excessive oxidative stress and exacerbated myocardium injury after AMI. Increased apoptosis and inflammation response in the ischemic myocardium contribute to this deterioration, whereas enhanced autophagy plays a protective role. Myocardial inflammation after AMI was much more severe in SOD1 KO mice than in wild-type mice. Pretreatment with the H2S donor NaHS reduced autophagy and apoptosis levels in the ischemic myocardium and alleviated the regional inflammation response in the cardiac tissues of SOD1 KO mice. Moreover, autophagy and apoptosis levels were significantly enhanced in SOD1 knockdown primary neonatal rat cardiomyocytes (NRCMs) under glucose deprivation. Pretreatment with NaHS can partially inhibit this elevation. Taken together, we found that excessive oxidative stress can aggravate cardiac injury during AMI. Exogenous H2S can alleviate cardiac injury during AMI by reducing apoptosis and inflammation response in heart tissues under oxidative stress.

Supplemental Digital Content is available in the text, Osteoporosis (OP) is a disease characterized by decreased bone mineral density (BMD) and an increased risk of osteoporotic fractures. Nutritional factors (including glucose and fats lipids), have been implicated in OP. We hypothesized that the levels of blood glucose and lipids could be biomarkers for predicting the risk of OP. To test this hypothesis, we evaluated the potential relationship between BMD and levels of blood glucose and lipids via a community-based study in China. This was a community-based cross-section analysis, and a total of 8584 cases were investigated. The BMD of the left calcaneus was measured using an ultrasonic bone densitometer. The levels of blood glucose (fasting blood glucose [FBG], 2-h blood glucose [2hBG], and glycosylated hemoglobin [HbAlc]), and lipids (triglyceride [TG], total cholesterol [TC], low-density lipoprotein cholesterol [LDL-C], and high-density lipoprotein cholesterol [HDL-C]) were measured and analyzed. In our study population, the levels of FBG, 2hBG, HbAlc, TC, LDL-C and HDL-C were higher in the OP group than in the low bone density and the normal bone density groups, while the levels of HbAlc, TC, and LDL-C in the low bone density group were higher than those in the normal bone density group. In males, the level of blood LDL-C in the low bone density group was higher than that in the normal bone density group. In postmenopausal subjects, the levels of FBG, 2hBG and HbA1C were higher than those in the normal bone density groups, and the level of HbA1C in the low bone density group was higher than that in the normal bone density group. Pearson linear trend analysis demonstrated that BMD was positively associated with TC and LDL-C in males and negatively associated with FBG, 2hBG and HbA1C in postmenopausal females. Moreover, logistic analysis showed that BMD was correlated with TC in premenopausal females and HbA1C in postmenopausal females. OP is generally associated with abnormal levels of blood glucose and/or lipids; nevertheless, the relationship between OP and abnormal levels of blood glucose and/or lipids is complicate and different subpopulations may have different susceptibilities. Therefore, further detailed studies are warranted.

To determine the effects of transient receptor potential vanilloid type 1 (TRPV1) channel ablation and a chemokine receptor 2 (CCR2) antagonist on salt-sensitive hypertension-induced renal injury.Wild-type (WT) and TRPV1-null mutant (TRPV1(-/-)) mice were subjected to uninephrectomy and deoxycorticosterone acetate (DOCA)-salt treatment for 4 weeks with or without a CCR2 antagonist, RS504393 (n=8 for all the 4 groups). Sham WT and TRPV1(-/-) mice (both n=7) underwent uninephrectomy without receiving DOCA and saline. Systolic blood pressure, urinary excretion of albumin, 8-isoprostane and creatinine clearance for 24 hours were assayed during the experimental period and at the end of the 4-week treatment. The morphological analysis was performed in renal histological sections, including glomerulosclerosis, tubulointerstitial injury, and monocyte/macrophage infiltration.Compared to the corresponding control mice, DOCA-salt treatment in both WT and TRPV1(-/-) mice led to increased systolic blood pressure (SBP), enhanced urinary excretion of albumin and 8-isoprostane, decreased creatinine clearance, increased glomerulosclerosis and tubulointerstitial injury associated with enhanced monocyte/macrophage infiltration (all P0.05), all of which were much more severe in TRPV1(-/-) mice compared to WT mice with the exception of blood pressure (all P0.05). RS5043943 attenuated DOCA-salt-induced changes in renal function and morphology in WT and TRPV1(-/-) mice (all P0.05). There was no difference in blood pressure among DOCA-salt WT and TRPV1(-/-) mice with or without RS505393 with the exception of sham WT and TRPV1(-/-) mice (all P0.05).CCR2 antagonist inhibits DOCA-salt-induced renal injury and monocyte/macrophage infiltration in WT and TRPV1(-/-) mice with the greater in the latter strain. Activation of TRPV1 attenuates salt-sensitive hypertension-induced renal injury possibly via inhibition of CCR2-induced monocyte/macrophage infiltration.

Objective: We tested the hypothesis that occlusion of the superior mesenteric artery induces late preconditioning against myocardial infarction and examined the effects of pharmacological modifiers of inducible nitric oxide synthase activity on the late preconditioning in anesthetized rats. Methods: Rats underwent an intestinal ischemia preconditioning protocol (30 min occlusion of the superior mesenteric artery) or were sham-operated. They were subjected to a sustained 30 min of coronary occlusion and 180 min of reperfusion 24 h later. Results: In rats receiving no pharmacological intervention, the percentage of myocardial infarct within the area at risk and left ventricle was 72±4% and 31±2%, respectively, in sham-operated rats, and these were significantly reduced to 44±4% and 23±2% ( P

To investigate whether nitric oxide (NO) in the central nervous system is involved in the decrease in renal sympathetic nerve activity (RSNA) during acute cardiac tamponade in conscious rabbits, we examined the effect of 7-nitroindazole (7-NI), a selective inhibitor of neuronal nitric oxide synthase in vivo, on RSNA during acute cardiac tamponade in chronically installed conscious rabbits. Cardiac tamponade was produced by intrapericardial infusion of physiological saline at 2 ml/30 s. Mean arterial pressure (MAP) remained constant initially but RSNA increased to 218±24% when we started injection of physiological saline into the pericardial space. Concomitantly after MAP fell to 51±1 mm Hg by subsequent injection of the saline into the pericardial space, RSNA decreased to 45±6%. If 7-NI (50 mg/kg) was administered intraperitoneally 35 min before the beginning of cardiac tamponade, the decline in RSNA caused by cardiac tamponade was markedly counteracted. Brain nitric oxide synthase (NOS) activity in the cerebral cortex and medulla oblongata, assessed by the conversion of labelled arginine to citrulline, was inhibited by 48% and 44% after the intraperitoneal administration of 7-NI. These results indicate that acute cardiac tamponade elicits a biphasic effect on RSNA, which rises during non-hypotensive period and then falls during hypotension in conscious rabbits. The decrease in RSNA was abolished by treatment with 7-NI, suggesting that the abrupt decrease in RSNA during hypotension induced by acute cardiac tamponade is mediated by NO in the central nervous system.

To evaluate the effects of Jiashen Prescription (, JSP) on myocardial infarction (MI) size and cardiac function at the early stage of MI in rats.One hundred male Sprague-Dawley rats were subjected to sham-operation or MI induced by ligating the left anterior descending coronary artery. The rats with MI were treated with vehicle, JSP 3 and 6 g/(kg·d), or losartan 10 mg/(kg·d) for 1 week.Compared with the vehicle-treated MI rats, 6 g/(kg·d) JSP reduced MI size 3 days after MI (P0.05), and attenuated the MI-induced increases in left ventricular end-diastolic and end-systolic dimension and decreases in fractional shortening and ejection fraction 1 week after MI (P0.05). In addition, 6 g/(kg·d) JSP and losartan were equally effective in reducing MI size and enhancing cardiac functional recovery.JSP reduces MI size and improves cardiac function after MI, suggesting that JSP has potential as a therapy for MI.

To determine the role of chemokine receptor 2 (CCR2) in the development of salt-sensitive hypertension-induced renal damage.We investigated the renal damage induced by uninephrectomy and deoxycorticosterone acetate (DOCA)-salt in mice treated with or without a selective CCR2 antagonist RS504393 for 4 weeks. Sham mice underwent uninephrectomy without receiving DOCA and saline. Systolic blood pressure, urinary excretion of albumin and 8-isoprostane, creatinine clearance, glomerulosclerosis, renal tubulointerstitial injury, and renal monocyte/macrophage infiltration were measured.DOCA-salt treatment led to increased systolic blood pressure, increased urinary excretion of albumin and 8-isoprostane, decreased creatinine clearance, glomerulosclerosis, renal tubulointerstitial injury, and renal monocyte/macrophage infiltration compared with the sham mice (P0.05). All of them were prevented by CCR2 inhibition (P0.05).Blockade of CCR2 prevents renal damage induced by DOCA-salt treatment, suggesting that CCR2-mediated monocyte/macrophage infiltration may contribute to salt-sensitive hypertension-induced renal injury.

Objective: The aim of this study was to investigate the role of inducible nitric oxide synthase (iNOS) as a trigger in lipopolysaccharide (LPS)-induced late preconditioning against myocardial infarction. Methods: Rats were pretreated intraperitoneally with two different doses of LPS (0.5 or 2.5 mg/kg) or normal saline (control) 24 h prior to lethal myocardial ischemia. Subsequently, all rats were subjected to a sustained 30-min coronary occlusion followed by 180-min reperfusion. In the second study, total RNA and protein were extracted from myocardium of the control and LPS-treated rats (after 4, 6 and 24 h of treatment) for reverse transcription-polymerase chain reaction and Western blot analysis. Results: In LPS (2.5 mg/kg, but not 0.5 mg/kg)-treated rats receiving no pharmacological intervention, the percentage of myocardial infarct within the area at risk and left ventricle was significantly reduced to 42±4 and 24±2% ( P

Objective: The present study was designed to test the hypothesis that intestinal ischemia results in an early preconditioning against myocardial infarction and that the mechanism of the early preconditioning involves the activation of protein kinase C-mitochondrial KATP channel signaling pathway in anesthetized rats. Methods: Rats were either preconditioned with a 25-min occlusion of the superior mesenteric artery followed by 15 min of reperfusion or underwent a 40-min sham period. Subsequently, all rats were subjected to a sustained 30 min of coronary occlusion and 180 min of reperfusion. Infarct size was determined by triphenyltetrazolium chloride staining. Results: In sham-operated rats receiving no pharmacological intervention, the percentage of myocardial infarct within the area at risk and left ventricle was 73±4% and 31±2%, respectively, and these were significantly reduced to 44±4% and 23±1% ( P

SUMMARY 1. The present study was planned to: (i) determine whether the baroreflex control of heart rate (HR) and renal sympathetic nerve activity (RSNA) was attenuated during reperfusion of short-term ischaemic myocardium; and (ii) study whether blockade of prostaglandin synthesis with indomethacin reversed the inhibitory baroreflex. 2. Arterial pressure was lowered with intravenous sodium nitroprusside before coronary occlusion and 3 min after release of a 5 min occlusion of the left circumflex coronary artery in anaesthetized rabbits. The protocol was repeated 20 min after indomethacin (5 mg/kg, i.v.) or indomethacin vehicle (50 mmol/L tris(hydroxymethyl)aminomethane buffer, pH 8.4) treatment. In addition, this study was performed in a group of vagotomized rabbits. 3. Before indomethacin treatment, the slope of the mean arterial pressure (MAP)–RSNA relationship decreased from –3.3±0.77 to –2.01±0.69% change in RSNA/mmHg (P < 0.05) during reperfusion of ischaemic myocardium in intact rabbits. The decrease in the slope was reversed by administration of indomethacin. However, the decrease in the slope was not reversed by indomethacin vehicle. Furthermore, the reduction in the slope of the MAP–RSNA relationship during reperfusion of ischaemic myocardium was abolished in vagotomized rabbits. However, there was no inhibition of the slope of the MAP–HR relationship during reperfusion of ischaemic myocardium in either intact or vagotomized rabbits. 4. In conclusion, our data suggest that prostaglandins released by ischaemic myocardium can attenuate the baroreflex-mediated response of RSNA to lowered arterial pressure via vagal afferents during reperfusion of short-term ischaemic myocardium.