Abstract 442: Intralipid Protects the Heart in Late Pregnancy Against Ischemia/Reperfusion Injury by Reducing Cardiomyocyte Apoptosis via Mir122 Induction

2016 ◽  
Vol 119 (suppl_1) ◽  
Author(s):  
Jingyuan Li ◽  
Negar Motayagheni ◽  
Neusha Barakati ◽  
Mansoureh Eghbali

The prevalence of coronary artery disease in late pregnancy (LP) has increased recently due to significant changes in women’s lifestyle patterns (age, stress, smoking, diabetes and chronic hypertension). Myocardial infarction during LP and the peripartum is associated with significant maternal mortality and morbidity compared to non pregnant women for unclear reasons. We have recently demonstrated that cardiac vulnerability to I/R injury drastically increases in LP rodents, leading to myocardial infarct size ~4 fold greater than in non-pregnant controls. We also discovered that administration of intralipid (an emulsion of soy bean oil, egg yolk phospholipids and glycerol) at reperfusion resulted in ~60% reduction in infarct size of the heart in LP rat subjected to I/R injury. However, the molecular mechanisms underlying intralipid-induced cardioprotection in late pregnancy is not clear. Here we hypothesized that intralipid protects the heart in late pregnancy by regulating the levels of specific microRNAs. The left anterior descending coronary artery was occluded in LP rats (21-22 days of pregnancy) for 45 min followed by 3 hr of reperfusion. One single bolus of PBS (control group) or 20% intralipid (intralipid group) was applied through the femoral vein 5 min before the reperfusion. The hearts of control and intralipid groups were used for microRNA microarray analysis (Ocean Ridge Biosciences). MicroRNA-microarray analysis identified MiR122 as a novel micro-RNA which its expression was strikingly upregulated more than 10 fold in the heart of LP rats in intralipid group compared to control group. miR122 regulates apoptosis in cardiomyocytes subjected to hypoxia/reoxygenation since miR122-overexpression resulted in reduced apoptosis, whereas knockdown of miR122 enhanced apoptosis. Pyruvate kinase isoform M2 (PKM2), which is known to regulate cell apoptosis in the liver, is a direct target of miR122. Our data show that PKM2 and caspase 3 are two targets of miR122 since the expression of PKM2 and capase-3 in the heats subjected to I/R was significantly lower in intralipid group compared to control group in LP. In conclusion intralipid protects the heart in late pregnancy against ischemia/reperfusion injury via inducing miR122 by targeting PKM2.

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Maha Sadek El Derh ◽  
Samar Mohamed Abdel Twab ◽  
Mohamed Elgouhary

Abstract Background Off pump coronary artery revascularization (OPCAB) surgeries have benefits over the conventional on pump cardiac surgery, because it avoids the trauma caused by cardiopulmonary bypass (CPB) and minimize aortic manipulation. However, some disadvantages of OPCAB include the concern of ineffective coronary revascularization. Some drugs have shown the ability to protect the myocardium in different studies, by different methods. The usage of intralipid has been shown to make a better functional recovery of the cardiac muscles and help to decrease the myocardial infarct size, it shortens the action potential time, which show polyunsaturated fatty acids diets mechanism as an antiarrhythmic drug, and are associated with low incidence of coronary artery disease. Methods We divided patients into two groups according to the randomization envelopes: intralipid group (group A) received 1.5 ml/kg intralipid 20% through central venous line after sternotomy over 1 h and during infusion, blood pressure, heart rate, and temperature were monitored all through the infusion time. Control group (group B) received normal saline 0.9% in the same volume over the same duration. Results This study showed that infusion of 1.5 ml/kg intralipid after sternotomy in off pump coronary artery revascularization given as preconditioning agent improve the myocardial ischemia reperfusion injury, decrease the need for high doses of nor adrenaline infusion after revascularization, earlier normalization in troponin levels starting 24 h after surgery and higher values of cardiac index were measured in ICU using PICCO. Conclusions This study showed the benefits of infusion of 1.5 ml/kg of intralipid after sternotomy, in preconditioning during OPCABG. Preconditioning with intralipid proved to decrease reperfusion injury in myocardium expressed by improvement in cardiac functions (EF and cardiac index) and normalization of specific cardiac marker (cardiac troponin I).


2007 ◽  
Vol 292 (6) ◽  
pp. H3158-H3163 ◽  
Author(s):  
Aliaksandr Bulhak ◽  
Joy Roy ◽  
Ulf Hedin ◽  
Per-Ove Sjöquist ◽  
John Pernow

Hydroxymethyl glutaryl (HMG)-coenzyme A (CoA) reductase inhibitors (statins) protect the myocardium against ischemia-reperfusion injury via a mechanism unrelated to cholesterol lowering. Statins may inhibit isoprenylation and thereby prevent activation of proteins such as RhoA. We hypothesized that statins protect the myocardium against ischemia-reperfusion injury via a mechanism involving inhibition of geranylgeranyl pyrophosphate synthesis and translocation of RhoA to the plasma membrane. Sprague-Dawley rats were given either the HMG-CoA reductase inhibitor rosuvastatin, geranylgeranyl pyrophosphate dissolved in methanol, the combination of rosuvastatin and geranylgeranyl pyrophosphate, rosuvastatin and methanol, or distilled water (control) by intraperitoneal injection for 48 h before ischemia-reperfusion. Animals were anesthetized and either subjected to 30 min of coronary artery occlusion followed by 2 h of reperfusion whereat infarct size was determined, or the expression of RhoA protein was determined in cytosolic and membrane fractions of nonischemic myocardium. There were no significant differences in hemodynamics between the control group and the other groups before ischemia or during ischemia and reperfusion. The infarct size was 80 ± 3% of the area at risk in the control group. Rosuvastatin reduced infarct size to 64 ± 2% ( P < 0.001 vs. control). Addition of geranylgeranyl pyrophosphate (77 ± 2%, P < 0.01 vs. rosuvastatin) but not methanol (65 ± 2%, not significant vs. rosuvastatin) abolished the cardioprotective effect of rosuvastatin. Geranylgeranyl pyrophosphate alone did not affect infarct size per se (84 ± 2%). Rosuvastatin increased the cytosol-to-membrane ratio of RhoA protein in the myocardium ( P < 0.05 vs. control). These changes were abolished by addition of geranylgeranyl pyrophosphate. We conclude that the cardioprotection and the increase of the RhoA cytosol-to-membrane ratio induced by rosuvastatin in vivo are blocked by geranylgeranyl pyrophosphate. The inhibition of geranylgeranyl pyrophosphate formation and subsequent modulation of cytosol/membrane-bound RhoA are of importance for the protective effect of statins against myocardial ischemia-reperfusion injury.


2004 ◽  
Vol 286 (5) ◽  
pp. H1923-H1935 ◽  
Author(s):  
James D. McCully ◽  
Hidetaka Wakiyama ◽  
Yng-Ju Hsieh ◽  
Mara Jones ◽  
Sidney Levitsky

Necrosis and apoptosis differentially contribute to myocardial injury. Determination of the contribution of these processes in ischemia-reperfusion injury would allow for the preservation of myocardial tissue. Necrosis and apoptosis were investigated in Langendorff-perfused rabbit hearts ( n = 47) subjected to 0 (Control group), 5 (GI-5), 10 (GI-10), 15 (GI-15), 20 (GI-20), 25 (GI-25), and 30 min (GI-30) of global ischemia (GI) and 120 min of reperfusion. Myocardial injury was determined by triphenyltetrazolium chloride (TTC) staining, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL), bax, bcl2, poly(ADP)ribose polymerase (PARP) cleavage, caspase-3, -8, and -9 cleavage and activity, Fas ligand (FasL), and Fas-activated death domain (FADD). The contribution of apoptosis was determined separately ( n = 42) using irreversible caspase-3, -8, and -9 inhibitors. Left ventricular peak developed pressure (LVPDP) and systolic shortening (SS) were significantly decreased and infarct size and TUNEL-positive cells were significantly increased ( P < 0.05 vs. Control group) at GI-20, GI-25, and GI-30. Proapoptotic bax, PARP cleavage, and caspase-3 and -9 cleavage and activity were apparent at GI-5 to GI-30. Fas, FADD, and caspase-8 cleavage and activity were unaltered. Irreversible inhibition of caspase-3 and -9 activity significantly decreased ( P < 0.05) infarct size at GI-25 and GI-30 but had no effect on LVPDP or SS. Myocardial injury results from a significant increase in both necrosis and apoptosis ( P < 0.05 vs. Control group) evident by TUNEL, TTC staining, and caspase activity at GI-20. Intrinsic proapoptotic activation is evident early during ischemia but does not significantly contribute to infarct size before GI-25. The contribution of necrosis to infarct size at GI-20, GI-25, and GI-30 is significantly greater than that of apoptosis. Apoptosis is significantly decreased by caspase inhibition during early reperfusion, but this protection does not improve immediate postischemic functional recovery.


2006 ◽  
Vol 290 (2) ◽  
pp. H500-H505 ◽  
Author(s):  
Kasem Nithipatikom ◽  
Michael P. Endsley ◽  
Jeannine M. Moore ◽  
Marilyn A. Isbell ◽  
John R. Falck ◽  
...  

Cytochrome P-450 (CYP) ω-hydroxylases and their arachidonic acid (AA) metabolite, 20-hydroxyeicosatetraenoic acid (20-HETE), produce a detrimental effect on ischemia-reperfusion injury in canine hearts, and the inhibition of CYP ω-hydroxylases markedly reduces myocardial infarct size expressed as a percentage of the area at risk (IS/AAR, %). In this study, we demonstrated that a specific CYP ω-hydroxylase inhibitor, N-methylsulfonyl-12,12-dibromododec-11-enamide (DDMS), markedly reduced 20-HETE production during ischemia-reperfusion and reduced myocardial infarct size compared with control [19.5 ± 1.0% (control), 9.6 ± 1.5% (0.40 mg/kg DDMS), 4.0 ± 2.0% (0.81 mg/kg DDMS), P < 0.01]. In addition, 20-hydroxyeicosa-6( Z),15( Z)-dienoic acid (20-HEDE, a putative 20-HETE antagonist) significantly reduced myocardial infarct size from control [10.3 ± 1.3% (0.032 mg/kg 20-HEDE) and 5.9 ± 1.9% (0.064 mg/kg 20-HEDE), P < 0.05]. We further demonstrated that one 5-min period of ischemic preconditioning (IPC) reduced infarct size to a similar extent as that observed with the high doses of DDMS and 20-HEDE, and the higher dose of DDMS given simultaneously with IPC augmented the infarct size reduction [9.9 ± 2.8% (IPC) to 2.5 ± 1.4% (0.81 mg/kg DDMS), P < 0.05] to a greater degree than that observed with either treatment alone. These results suggest an important negative role for endogenous CYP ω-hydroxylases and their product, 20-HETE, to exacerbate myocardial injury in canine myocardium. Furthermore, for the first time, this study demonstrates that the effect of IPC and the inhibition of CYP ω-hydroxylase synthesis (DDMS) or its actions (20-HEDE) may have additive effects in protecting the canine heart from ischemia-reperfusion injury.


2000 ◽  
Vol 278 (4) ◽  
pp. H1084-H1090 ◽  
Author(s):  
Nilanjana Maulik ◽  
Tetsuya Yoshida ◽  
Richard M. Engelman ◽  
Debasis Bagchi ◽  
Hajime Otani ◽  
...  

To examine whether nutritional supplementation of coenzyme Q10(CoQ10) can reduce myocardial ischemia-reperfusion injury, a group of swine was fed a regular diet supplemented with CoQ10 (5 mg ⋅ kg− 1 ⋅ day− 1) for 30 days. Another group of pigs that were fed a regular diet supplemented with placebo served as a control. After 30 days, isolated in situ pig hearts were prepared and hearts were perfused with a cardiopulmonary pump system. Each heart was subjected to 15 min of regional ischemia by snaring of the left anterior descending coronary artery, followed by 60 min of hypothermic cardioplegic global ischemia and 120 min of reperfusion. After the experiments were completed, myocardial infarct size was measured by triphenyltrazolium chloride staining methods. Postischemic left ventricular contractile function was better recovered in the CoQ10 group than in the control group of pigs. CoQ10-fed pigs revealed less myocardial infarction and less creatine kinase release from the coronary effluent compared with control pigs. The experimental group also demonstrated a smaller amount of malonaldehyde in the coronary effluent and a higher content of the endogenous antioxidants ascorbate and thiol. Significant induction of the expression of ubiquitin mRNA was also found in the hearts of the CoQ10-fed group. The results of this study demonstrate that nutritional supplementation of CoQ10 renders the hearts resistant to ischemia-reperfusion injury, probably by reducing the oxidative stress.


Sign in / Sign up

Export Citation Format

Share Document