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The purpose of this study was to investigate whether or not angiotensin II type 1 receptor blocker irbesartan (ARB) with a partial agonist of PPAR-γ could protect against chronic nocturnal intermittent hypoxia (CIH)–induced cardiac Fas/FasL-mediated to mitochondria-mediated apoptosis. Sprague–Dawley rats were in a normoxic control group (CON-G), or rats were in a chronic nocturnal intermittent hypoxia group (HP-G, from 3 to 7% oxygen versus 21% oxygen per forty seconds cycle, nocturnally 8 h per day for 1 month), or rats were in a chronic nocturnal intermittent hypoxia group pretreated with ARB (50 mg/kg/day, S.C.) (ARB-HP-G). Echocardiography, H&E staining, TUNEL staining, and Western blotting were measured in the left ventricle. Hypoxia-induced SIRT1 degradation, Fas receptors, FADD, active caspase-8 and caspase-3 (Fas/FasL apoptotic pathway) and Bax, tBid, active caspase-9 and -3 (mitochondrial apoptotic pathway) and TUNEL-positive apoptosis were reduced in ARB-HP-G when compared with HP-G. IGF-I, IGF1 receptor, p-PI3k, p-Akt, Bcl2, and Bcl-XL (IGF1/PI3K/AKT pro-survival pathway) were increased in ARB-HP-G compared to HP-G. Our findings suggest that the ARB may prevent cardiac Fas/FasL to mitochondrial apoptotic pathways and enhance cardiac IGF1/PI3K/AKT pro-survival pathway in the sleep apnea model associated with JNK de-activation and SIRT1 upregulation. ARB prevents chronic sleep apnea–enhanced cardiac apoptosis via enhancing survival pathways.

Elevated plasma concentration of total homocysteine is a pathological condition that causes vascular endothelial injury and subsequently leads to the progression of endothelial apoptosis in atherosclerosis. Epigallocatechin gallate (EGCG), a well-known anti-oxidant in green tea, has been reported with benefits on metabolic and cardiovascular diseases. This study aimed to explore that EGCG ameliorates homocysteine-induced endothelial cell apoptosis through enhancing the sirtuin 1 (SIRT1)/AMP-activated protein kinase (AMPK) survival signaling pathway. Human umbilical endothelial cells were treated with homocysteine in the presence or absence of EGCG. We found that EGCG significantly increased the activities of SIRT1 and AMPK. EGCG diminished homocysteine-mediated nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activation by inhibiting protein kinase C activation as well as reactive oxygen species (ROS) generation and recovered the activity of the endogenous antioxidant enzyme, superoxidase dismutase (SOD). Besides, EGCG also restores homocysteine-mediated dephosphorylation of Akt and decreases endothelial NO synthase (eNOS) expression. Furthermore, EGCG ameliorates homocysteine-activated pro-apoptotic events. The present study shows that EGCG prevents homocysteine-induced endothelial cell apoptosis via enhancing SIRT1/AMPK as well as Akt/eNOS signaling pathways. Results from this study indicated that EGCG might have some benefits for hyperhomocysteinemia.

It has been well-documented that the consumption of deep sea water (DSW) has beneficial effects on myocardial hypertrophy and cardiac apoptosis induced by hypercholesterolemia. However, the molecular mechanisms for the anti-inflammatory effects of DSW on diabetic cardiomyopathy are still largely unclear. The main purpose of this present study was to test the hypothesis that DSW exerts anti-inflammatory effects through the suppression of the TNF-α-mediated signaling pathways. IP injection of streptozotocin (STZ) at the dose of 65 mg/kg was used to establish a diabetes rat model. DSW mineral extracts that diluted in desalinated water were prepared in three different dosages and administered to the rats through gavages for 4 weeks. These dosages are DSW-1X (equivalent to 37 mg Mg2+ /kg/day), 2X (equivalent to 74 mg Mg2+ /kg/day) and 3X (equivalent to 111 mg Mg2+ mg/kg/day). Immunofluorescence staining and Western blot showed that the protein expression level of TNF-α was markedly higher in the STZ-induced diabetic rat hearts than in the control group. Consequently, the phosphorylation levels of the TNF-α-modulated downstream signaling molecules and P38 mitogen-activated protein kinases (MAPKs) were notably elevated in heart tissues of STZ-induced diabetes. These higher phosphorylation levels subsequently upregulated NF-κB-modulated inflammatory mediators, such as cyclooxygenase (COX)-II and inducible nitric oxide synthase (iNOS). However, treatment with DSW as well as MgSO4 , the main mineral in DSW, significantly reversed all the alterations. These findings suggest that DSW has potential as a therapeutic agent for preventing diabetes-related cardiovascular diseases.

Stem cell therapy is a promising treatment for hepatopathy due to diabetes mellitus (DM); oral resveratrol treatment exhibits protective effects. We investigated whether protective effects could be produced in liver of diabetic rats receiving autologous adipose-derived stem cell transplantation (ADSC) plus oral resveratrol administration. Male rats were divided into four groups: sham group; streptozotocin induced DM group; DM + ADSC group, in which DM rats were treated with 10

We previously reported that deep sea water (DSW) prolongs the life span of streptozotocin (STZ)-induced diabetic rats by the compensatory augmentation of the insulin like growth factor (IGF)-I survival signaling and inhibition of apoptosis. Here, we investigated the effects of DSW on cardiac hypertrophy in diabetic rats. Cardiac hypertrophy was induced in rats by using STZ (65 mg/kg) administered via IP injection. DSW was prepared by mixing DSW mineral extracts and desalinated water. Different dosages of DSW-1X (equivalent to 37 mg Mg2+·kg−1·day−1), 2X (equivalent to 74 mg Mg2+·kg−1·day−1) and 3X (equivalent to 111 mg Mg2+·kg−1·day−1) were administered to the rats through gavage for 4 wk. Cardiac hypertrophy was evaluated by the heart weight-to-body weight ratio and the cardiac tissue cross-sectional area after hematoxylin and eosin staining. The protein levels of the cardiac hypertrophy signaling molecules were determined by Western blot. Our results showed that the suppressive effects of the DSW treatment on STZ-induced cardiac hypertrophy were comparable to those of MgSO4administration and that the hypertrophic marker brain natriuretic peptide (BNP) was decreased by DSW. In addition, DSW attenuated both the eccentric hypertrophy signaling pathway, IL-6-MEK-STAT3, and the concentric signaling pathway, IGF-II-PKCα-CaMKII, in DM rat hearts. The cardiac hypertrophy-associated activation of extracellular signal-regulated kinase (ERK) and the upregulation of the transcription factor GATA binding protein 4 (GATA4) were also negated by treatment with DSW. The results from this study suggest that DSW could be a potential therapeutic agent for the prevention and treatment of diabetic cardiac hypertrophy.NEW & NOTEWORTHY Deep sea water, containing high levels of minerals, improve cardiac hypertrophy in diabetic rats through attenuating the eccentric signaling pathway, IL-6-MEK5-STAT3, and concentric signaling pathway, IGF2-PKCα-CaMKII. The results from this study suggest that deep sea water could be a potential therapeutic agent for the prevention and treatment of diabetic cardiac hypertrophy.

The effects of Gynura bicolor aqueous extract (GAE) upon glycemic control, coagulation disorder, lipid accumulation, and glycative, oxidative, and inflammatory stresses in diabetic mice were investigated. Mice were treated with streptozotocin to induce type 1 diabetes. Diabetic mice were divided into four groups, consumed GAE at 0%, 0.25%, 0.5%, or 1%. Normal group consumed standard mouse basal diet. After 8-week treatments, mice were sacrificed after overnight fasting. Results showed that GAE supplement at 0.5% and 1% decreased plasma glucose level and increased plasma insulin level. Diabetes lowered plasma level of protein C and anti-thrombin III; and raised plasminogen activator inhibitor-1 activity and fibrinogen level in plasma. GAE supplement at 0.5% and 1% reversed these alterations. Histological data, assayed by Oil Red O stain, indicated that GAE supplement decreased lipid accumulation in liver. GAE supplement at 0.5% and 1% reduced aldose reductase activity in heart and kidney; and lowered the levels of carboxymethyllysine and pentosidine in plasma and two organs. Diabetes decreased glutathione content, and increased reactive oxygen species, interleukin (IL)-1β, IL-6, and tumor necrosis factor-α production in heart and kidney. GAE supplement at three test doses reversed these changes. Diabetes upregulated the mRNA expression of p38 and nuclear factor kappa (NF-κ)B in heart and kidney. GAE supplement suppressed the mRNA expression of both p38 and NF-κB. These novel findings suggest that Gynura bicolor is a potent functional food for diabetic prevention or alleviation.

Oxidative stress has been implicated in the pathogenesis of atherosclerotic cardiovascular diseases. Dietary supplementation of anti-oxidants has been reported to have beneficial effects on the prevention of atherogenic diseases. Luteolin (a natural flavonoid) has been shown to possess antimutagenic, antitumorigenic, anti-oxidant and anti-inflammatory properties. However, the effects and underlying molecular mechanisms of luteolin on cardiovascular systems are poorly explored. Therefore, the aim of the present study was to test whether luteolin could protect against oxidative stress-induced endothelial cell injury and explore the underlying mechanisms. In this study, human umbilical vein endothelial cells (HUVECs) were pre-treated with luteolin followed by hydrogen peroxide induction (H2O2). Our results showed that luteolin protected against H2O2-induced oxidative stress and ameliorated ROS and superoxide generation. In addition, we found that luteolin treatment inhibited the H2O2-induced membrane assembly of NADPH oxidase subunits, which was further confirmed by specifically inhibiting NADPH oxidase using DPI treatment. Furthermore, pAMPK protein expression was enhanced and p-PKC isoforms were significantly down-regulated by luteolin treatment in a dose-dependent manner, and a similar effect was observed upon DPI treatment. However, co-treatment with the specific inhibitor of AMPK (Compound C) restored p-PKC levels suggesting the role of AMPK signaling in regulating p-PKC expression under oxidative stress condition in HUVECs. Finally, we confirmed using siRNAs and specific inhibitor and/or activator of AMPK (AICAR) that luteolin treatment induced AMPK is a key player and regulator of activated expression of PKC isoforms and thereby confers protection against H2O2-induced oxidative stress in HUVECs.

The heart is a very dynamic pumping organ working perpetually to maintain a constant blood supply to the whole body to transport oxygen and nutrients. Unfortunately, it is also subjected to various stresses based on physiological or pathological conditions, particularly more vulnerable to damages caused by oxidative stress. In this study, we investigate the molecular mechanism and contribution of IGF-IIRα in endoplasmic reticulum stress induction in the heart under doxorubicin-induced cardiotoxicity. Using in vitro H9c2 cells, in vivo transgenic rat cardiac tissues, siRNAs against CHOP, chemical ER chaperone PBA, and western blot experiments, we found that IGF-IIRα overexpression enhanced ER stress markers ATF4, ATF6, IRE1α, and PERK which were further aggravated by DOX treatment. This was accompanied by a significant perturbation in stress-associated MAPKs such as p38 and JNK. Interestingly, PARKIN, a stress responsive cellular protective mediator was significantly downregulated by IGF-IIRα concomitant with decreased expression of ER chaperone GRP78. Furthermore, ER stress-associated pro-apoptotic factor CHOP was increased considerably in a dose-dependent manner followed by elevated c-caspase-12 and c-caspase-3 activities. Conversely, treatment of H9c2 cells with chemical ER chaperone PBA or siRNA against CHOP abolished the IGF-IIRα-induced ER stress responses. Altogether, these findings suggested that IGF-IIRα contributes to ER stress induction and inhibits cellular stress coping proteins while increasing pro-apoptotic factors feeding into a cardio myocyte damage program that eventually paves the way to heart failure.

Diabetes is a metabolic disorder that damages many organs. We investigated the effects of reperfusion using lactate Ringer's solution (LR) in a diabetic animal model. Eight-week-old rats were divided into groups: control, hemorrhagic shock induced (HS), diabetes mellitus (DM), DM plus HS (DM + HS) and DM rats that received LR after HS (DM + HS + LR). HS was induced by withdrawing blood from the femoral artery and arterial pressure was maintained at 40 mm Hg for 1 h. Animals were perfused with either withdrawn blood or LR. Rats were sacrificed and hearts were collected from all groups. Histopathological studies were performed using left ventricles and western blotting analysis was performed using protein extracted from the left ventricle. Using the TUNEL assay, we found more apoptotic cells in the DM + HS group compared to the control group, whereas in animals resuscitated with LR, the number of apoptotic cells was reduced. Western blotting showed a significant reduction in apoptotic markers, cyt

Defective Wnt/β-Catenin signaling, activated under various pathological conditions, can result in cardiac and vascular abnormalities. In the present study, the possible role of β-catenin over expression during cardiac hypertrophy was investigated. Ten samples from hearts of human patients with acute infarction, and granulation tissue from 20 patients and 10 from normal ones were collected in order to investigate roles of β-catenin in cardiac hypertrophy. H9c2 cardiomyoblast cells and Wistar rat primary neonatal cardiomyocytes were overexpressed with β-catenin. Expression levels of β-catenin protein were increased in human acute infarction tissues and rat hypertension heart tissues. Overexpression of this transcription factor induced actin filament formation and increased hypertrophic marker protein levels via MAPK pathway. In addition, β-catenin overexpression also resulted in increased elevation of NFATc3 and p-GATA4. Therefore, acute infarction resulted in β-catenin overexpression mediated hypertrophy in cardiomyocytes regulated through MAPK pathway.

In this study, a rat carotid balloon injury-animal model was used to elucidate the temporal relation of hypertrophy in the progression of cardiac damage and the role of insulin-like growth factor (IGF)-I survival pathway on course of the cardiac damage. Rats were subjected to carotid balloon-injury and examined at different time points. We further studied the heart-weight/body-weight-ratio, histology and protein expression to understand the pathological events associated with percutaneous transluminal coronary angioplasty (PTCA) induced damages. Protein expression analysis showed increased levels of IGF-I signaling pathway and mitogen-activated protein kinase (MAPK) signaling pathway after 2 h and after 2 d of carotid balloon injury. On the other hand, apoptosis signaling pathways were enhanced after 14 d of carotid balloon injury. According to the results, rat carotid balloon injury significantly induced IGF-I survival signaling and compensated hypertrophy pathway during the initial period of injury however after 14 d the proteins involved in apoptotic cell death were elevated and the proteins of the survival pathway and compensatory hypertrophy were significantly reduced.

The present study was aimed to investigate the protective effects of 17β-estradiol (E2) and estrogen receptor α (ERα) on isoproterenol (ISO)-treated H9c2 cardiomyoblast cells. In the present study, we treated H9c2 cells with ISO, a β-adrenergic receptor agonist, to induce myocardiac hypertrophy. Pre-administration of E2 or ERα (induced by doxycycline) and E2 plus ERα significantly prevented ISO-induced increase of cell size and cytosolic calcium accumulation, accompanied with increased mRNA of atrial natriuretic peptide and brain natriuretic peptide. However, ICI-ERs antagonist, and melatonin, a specific inhibitor for ERα, reversed the cardioprotective effects, suggesting that E2 action was mediated through ERα. Further evidences showed that E2 and ERα increased the protein level of GSK3β and protein phosphatase 2a inhibitor 2 (I2-PP2A), which subsequently enhanced the activation of I2-PP2A by disrupting PP2A activity and maintains normal calcium outflow. Collectively, E2 and ERα inhibited hypertrophy by preventing cytosol calcium accumulation and by inhibiting the association between PP2A with Na+-Ca2+ exchanger via GSK3β and I2-PP2A activation.

Background Combination therapy with angiotensin-converting enzyme inhibitors (ACEI) and angiotensin II receptor blockers (ARB) has been stressed for its comprehensive blocking of the renin-angiotensin-aldosterone system, but the evidence for their respective safety and efficacy, in particular with stroke prevention, is still insufficient in population-based follow-up studies in the real world. Methods Using Taiwan's National Health Insurance claims data, we identified 5445 subjects aged 18years and older who had newly diagnosed hypertension in 1997–2010, from them diagnosed type 2 diabetes later. Among them, 2161 patients took ACEI, 1703 patients took ARB, 165 patients took both ACEI and ARB, and 1416 patients had neither. Results During the follow-up period, the stroke incidence density was the lowest (23.02 per 1000person-years) in ARB group, followed by the group with neither medication, the ACEI group, and ARB/ACEI combination group (24.06, 30.23, and 37.86 per 1000person-years, respectively). Compared with patients taking neither medication, the adjusted hazard ratios (HRs) were 1.27 (95% CI 1.02–1.58) for ACEI group, 0.95 (95% CI 0.74–1.22) for ARB group, and 1.56 (95% CI 0.99–2.47) for ARB/ACEI combined group. Greater reduction in risk of stroke was observed in patients with high dose ARB (adjusted HR=0·42, 95% CI 0·24–0·75). Conclusion Our findings support the practice that ARBs could be used, from the perspective of stroke prevention, as a first-line antihypertensive drug for patients with both hypertension and diabetes. The group with ARB regimen reduces 26% of stroke in contrast to the group with ACEI regimen.

Q10 is a powerful antioxidant often used in medical nutritional supplements for cancer treatment. This study determined whether Q10 could effectively prevent cardio-toxicity caused by doxorubicin treatment. Four week old SD rats were segregated into groups namely control, doxorubicin group (challenged with doxorubicin), Dox + Q10 group (with doxorubicin challenge and oral Q10 treatment), and Q10 group (with oral Q10 treatment). Doxorubicin groups received IP doxorubicin (2.5 mg/kg) every 3 days and Q10 groups received Q10 (10 mg/kg) every day. Three weeks of doxorubicin challenge caused significant reduction in heart weight, disarray in cardiomyocyte arrangement, elevation of collagen accumulation, enhancement of fibrosis and cell death associated proteins, and inhibition of survival proteins. However, Q10 effectively protected cardiomyocytes and ameliorated fibrosis and cell death induced by doxorubicin. Q10 is, therefore, evidently a potential drug to prevent heart damage caused by doxorubicin. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 679-689, 2017.

High-fat diets induce obesity, leading to cardiomyocyte fibrosis and autophagy imbalance. In addition, no previous studies have indicated that probiotics have potential health effects associated with cardiac fibrosis and autophagy in obese rats. This study investigates the effects of probiotics on high-fat (HF) diet-induced obesity and cardiac fibrosis and autophagy in rat hearts. Eight-week-old male Wistar rats were separated randomly into five equally sized experimental groups: Normal diet (control) and high-fat (HF) diet groups and groups fed a high-fat diet supplemented with low (HL), medium (HM) or high (HH) doses of multi-strain probiotic powders. These experiments were designed for an 8-week trial period. The myocardial architecture of the left ventricle was evaluated using Masson's trichrome staining and immunohistochemistry staining. Key probiotics-related pathway molecules were analyzed using western blotting. Abnormal myocardial architecture and enlarged interstitial spaces were observed in HF hearts. These interstitial spaces were significantly decreased in groups provided with multi-strain probiotics compared with HF hearts. Western blot analysis demonstrated that key components of the TGF/MMP2/MMP9 fibrosis pathways and ERK5/uPA/ANP cardiac hypertrophy pathways were significantly suppressed in probiotic groups compared to the HF group. Autophagy balance is very important in cardiomyocytes. In this study, we observed that the beclin-1/LC3B/Atg7 autophagy pathway in HF was increased after probiotic supplementation was significantly decreased. Together, these results suggest that oral administration of probiotics may attenuate cardiomyocyte fibrosis and cardiac hypertrophy and the autophagy-signaling pathway in obese rats.

This study investigates the cardio-protective effect of Nos. 1 and 5 extracts from Taiwan Mingjian Oolong Tea on H9c2 cardiomyoblast cells treated with isoproterenol (ISO). Treatment with Nos. 1 and 5 extracts increased cell viability and blocked apoptosis in ISO exposed H9c2 cells. Moreover, Nos. 1 and 5 extracts blocked hypertrophy markers like G[Formula: see text]s, calcineurin, NFATc3, and BNP, thereby increasing cell proliferation markers -PI3K and AKT in a dose dependent manner. In contrast, apoptotic proteins, such as caspase-3 and cytochrome c were decreased in H9c2 cells treated with Nos. 1 and 5 extracts. We confirmed that the protective effect of No. 1 extract was partially mediated through the expression of ERK and p38, however, the No. 5 extract showed a protective effect via the ERK, JNK, and p38 pathways. This evidence provides new insights into the pharmacological role and therapeutic mechanism of Taiwan Mingjian Oolong Tea in heart diseases.

Mitochondrial dysfunction is a major contributor to myocyte loss and the development of heart failure. Myocytes have quality control mechanisms to retain functional mitochondria by removing damaged mitochondria via specialized autophagy, i.e., mitophagy. The underlying mechanisms of fission affect the survival of cardiomyocytes, and left ventricular function in the heart is poorly understood. Here, we demonstrated the direct effect and potential mechanisms of mitochondrial functional defects associated with abnormal mitochondrial dynamics in heart failure. We observed that IGF-IIR signaling produced significant changes in mitochondrial morphology and function; such changes were associated with the altered expression and distribution of dynamin-related protein (Drp1) and mitofusin (Mfn2). IGF-IIR signaled extracellular signal-regulated kinase (ERK) activation to promote Drp1 phosphorylation and translocation to mitochondria for mitochondrial fission and mitochondrial dysfunction. Moreover, IGF-IIR signaling triggered Rab9-dependent autophagosome formation by the JNK-mediated phosphorylation of Bcl-2 at serine 87 and promoted ULK1/Beclin 1-dependent autophagic membrane formation. Excessive mitochondrial fission by Drp1 enhanced the Rab9-dependent autophagosome recognition and engulfing of damaged mitochondria and eventually decreased cardiomyocyte viability. Therefore, these results demonstrated the connection between Rab9-dependent autophagosomes and mitochondrial fission in cardiac myocytes, which provides a potential therapeutic strategy for treating heart disease.

Background Recent findings from clinical trials have indicated inconsistent associations between angiotensin II receptor blockers and the risk of cancer incidence. Furthermore, the relationship between antihypertensive drugs and prostate cancer in hypertensive patients remains unclear. Methods From Taiwan's national health insurance database, we identified 80,299 patients diagnosed with hypertension in 2001 and matched with 321,916 subjects without hypertension by age, income, urbanization level, and index day. A total of 684 hypertensive patients without antihypertensive drug use (drug non-user subcohort) were also matched (1:4) with 2736 patients on antihypertensive medication (drug subcohort) using the same criteria. Each subject in the two study groups was followed up for a maximum of nine years, during which death was considered a competing event when performing the stratified Fine and Gray regression hazards model for the estimation of prostate cancer risk for the cohorts. Uptake of antihypertensive prescription was considered a time-dependent variable. Results Our findings indicate that patients with hypertension are at significantly increased risk for prostate cancer incidence when compared to their matched non-hypertensive counterparts (sHR=6.80, 95% CI=1.97–23.44, p =0.0024). Among hypertensive patients, those with long term antihypertensive drug use are not at elevated risk of developing prostate cancer relative to non-users of antihypertensive drugs (1–5year vs. non-user sHR=0.99, 95% CI=0.32–3.05; >5year vs. non-user sHR=0.88, 95% CI=0.34–2.26). Conclusions Hypertension is considered a risk factor for prostate cancer. However, long term uptake of antihypertensive medication in male hypertensive patients should not be a concern for the development of prostate cancer.

Background: Hemorrhagic shock (HS) is the major cause of death from trauma. Hemorrhagic shock may lead to cellular hypoxia and organ damage. Our previous findings showed that HS induced a cardiac apoptosis pathway and synergistically caused myocardial cell damage in diabetic rats under trauma-induced HS. Tetramethylpyrazine (TMP) is a major biologically active ingredient purified from the rhizome of Ligusticum wallichii (called Chuang Xiong in Chinese). Chuan Xiong rescued cells from synergistic cardiomyoblast cell injury under high-glucose (HG) conditions plus hypoxia. TMP is one of the most important active ingredients that elevated the survival rate in ischemic brain injury and prevented inducible NO synthase expression to have anti-inflammatory effects against cell damage in different cell types. Method: Here, we further investigate whether TMP can protect against hypoxic (

The prevalence of obesity is high in older adults. Alcalase potato protein hydrolysate (APPH), a nutraceutical food, might have greater benefits and be more economical than hypolipidemic drugs. In this study, serum lipid profiles and heart protective effects were evaluated in high fat diet (HFD) induced hyperlipidemia in aging rats treated with APPH (15, 45 and 75 mg/kg/day) and probucol (500 mg/kg/day). APPH treatments reduced serum triacylglycerol (TG), total cholesterol (TC), and low density lipoprotein (LDL) levels to the normal levels expressed in the control group. Additionally, the IGF1R-PI3K-Akt survival pathway was reactivated, and Fas-FADD (Fas-associated death domain) induced apoptosis was inhibited by APPH treatments (15 and 45 mg/kg/day) in HFD aging rat hearts. APPH (75 mg/kg/day) rather than probucol (500 mg/kg/day) treatment could reduce serum lipids without affecting HDL expression. The heart protective effect of APPH in aging rats with hyperlipidemia was through lowering serum lipids and enhancing the activation of the compensatory IGF1R-PI3K-Akt survival pathway.

The insulin-like growth factor-II/mannose 6-phosphate receptor (IGF2R) over-expression correlates with heart disease progression. The IGF2R is not only an IGF2 clearance receptor, but it also triggers signal transduction, resulting in cardiac hypertrophy, apoptosis and fibrosis. The present study investigated the nuclear factor IL-3 (NFIL3), a transcription factor of the basic leucine zipper superfamily, and its potential pro-survival effects in cardiomyocytes. NFIL3 might play a key role in heart development and act as a survival factor in the heart, but the regulatory mechanisms are still unclear. IGF2 and IGF2R protein expression were highly increased in rat hearts subjected to hemorrhagic shock. IGF2R protein expression was also up-regulated in H9c2 cells exposed to hypoxia. Over-expression of NFIL3 in H9c2 cardiomyoblast cells inhibited the induction of hypoxia-induced apoptosis and down-regulated IGF2R expression levels. Gel shift assay, double-stranded DNA pull-down assay and chromatin immune-precipitation analyses indicated that NFIL3 binds directly to the IGF2R promoter region. Using a luciferase assay, we further observed NFIL3 repress IGF2R gene promoter activity. Our results demonstrate that NFIL3 is an important negative transcription factor, which through binding to the promoter of IGF2R, suppresses the apoptosis induced by IGF2R signaling in H9c2 cardiomyoblast cells under hypoxic conditions.

Consumption of deep sea minerals (DSM), such as magnesium, calcium, and potassium, is known to reduce hypercholesterolemia-induced myocardial hypertrophy and cardiac-apoptosis and provide protection against cardiovascular diseases. Heart diseases develop as a lethal complication among diabetic patients usually due to hyperglycemia-induced cardiac-apoptosis that causes severe cardiac-damages, heart failure, and reduced life expectancy. In this study, we investigated the potential of DSM and its related cardio-protection to increase the life expectancy in diabetic rats. In this study, a heart failure rat model was developed by using streptozotocin (65 mg kg(-1) ) IP injection. Different doses of DSM-1× (37 mg kg(-1) day(-1) ), 2× (74 mg kg(-1) day(-1) ) and 3× (111 mg kg(-1) day(-1) ), were administered to the rats through gavages for 4 weeks. The positive effects of DSM on the survival rate of diabetes rats were determined with respect to the corresponding effects of MgSO4 . Further, to understand the mechanism by which DSM enhances the survival of diabetic rats, their potential to regulate cardiac-apoptosis and control cardiac-dysfunction were examined. Echocardiogram, tissue staining, TUNEL assay, and Western blotting assay were used to investigate modulations in the myocardial contractile function and related signaling protein expression. The results showed that DSM regulate apoptosis and complement the cardiomyocyte proliferation by enhancing survival mechanisms. Moreover DSM significantly reduced the mortality rate and enhanced the survival rate of diabetic rats. Experimental results show that DSM administration can be an effective strategy to improve the life expectancy of diabetic subjects by improving cardiac-cell proliferation and by controlling cardiac-apoptosis and associated cardiac-dysfunction. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 769-781, 2016.

Objectives Prolactin (PRL) is a multifunctional hormone that influences multiple physiological processes. It has been shown to have a protective effect on the cardiovascular system; however, the mechanisms of this effect are poorly understood. The purpose of the study was to elucidate the role of PRL in intermittent hypoxia (IH)-induced apoptosis in the cardiovascular system. Method and results We established a hyperprolactinemic rat model by implanting two anterior pituitary (AP) glands into the renal capsule of male Sprague–Dawley rats. The rats were kept under normoxic conditions for 4weeks after implantation in order to reach the expression plateau of PRL in the plasma, and then treated with IH for 7 or 14days. Their hearts were then removed for histological and protein expression analyses. Cerebral cortex (CX)-grafted control rats challenged with IH displayed unique phenotypes such as a thicker heart wall, an abnormal myocardial architecture and an increased interstitial space of the left ventricle. They exhibited reduced expressions of p -JAK2, p -STAT5, cell cycle-dependent proteins (cyclin D1, cyclin E and cyclin A), IGF-IRα, PI3Kα, p -AKT and p -ERK1/2 in cardiomyocytes at 7days. Conclusions Our comprehensive analysis suggested that high plasma PRL can protect rat cardiomyocytes against IH through (1) the p -JAK2 and p -STAT5 pathways for transient cell proliferation, (2) the PI3Kα/AKT and MAPK survival pathways through IGF-I, and (3) the downregulation of IGF-II and ERK5, which inhibit cell hypertrophy.

High-fat-diet (HFD)-induced obesity is a major contributor to diabetes and cardiovascular disease. In this research 6 week old male hamsters (n = 10) fed with HFD showed significant deterioration in heart function as determined from their cardiac ejection fraction percentage (EF%) and fraction shortening percentage (FS%). The number of apoptosis positive cells and the expression of protein markers of apoptosis drastically increased in the HFD-fed hamsters. However, the effects were significantly reduced following the administration of a lipolysis-stimulating peptide-APPH which was derived from the Alcalase-hydrolysis of potato protein. Fifty days of APPH-treatment was effective in all the concentrations (15, 45 and 75 mg/kg/day) tested. The EF% and FS% measurements in the APPH treatment groups were comparable with that of the control group hamsters. The molecular events associated with the ameliorative effect of APPH were found to be potentially mediated by SIRT1 pathway indicating a restoration from the metabolic disorders induced by HFD.

Background/Aims: The risk of heart disease is higher in males than in females. However, this advantage of females declines with increasing age, presumably a consequence of decreased estrogen secretion and malfunctioning of the estrogen receptor. We previously demonstrated that 17β-estradiol (E2) prevents cardiomyocyte hypertrophy, autophagy and apoptosis via estrogen receptor α (ERα), but the effects of ERβ on myocardial injury remained elusive. The present paper thus, investigated the cardioprotective effects of estrogen (E2) and ERβ against hypoxia-induced cell death. Methods: Transient transfection of Tet-On ERβ gene construct was used to overexpress ERβ in hypoxia-treated H9c2 cardiomyoblast cells. Results: Our data revealed that IGF1R, Akt phosphorylation and Bcl-2 expression are enhanced by ERβ in H9c2 cells. Moreover, ERβ overexpression reduced accumulation of hypoxia-related proteins, autophagy-related proteins and mitochondria-apoptotic proteins and enhanced the protein levels of Bcl-2, pAkt and Bad under hypoxic condition. In neonatal rat ventricular myocytes (NRVMs), we observed that hypoxia induced cell apoptosis as measured by TUNEL staining, and E2 and/or ERβ could totally abolish hypoxia-induced apoptosis. The suppressive effects of E2 and/or ERβ in hypoxia-treated NRVMs were totally reversed by ER antagonist, ICI. Taken together, E2 and/or ERβ exert the protective effect through repressed hypoxia-inducible HIF-1α, BNIP3 and IGFBP-3 levels to restrain the hypoxia-induced autophagy and apoptosis effects in H9c2 cardiomyoblast cells. Conclusion: The results suggest that females probably could tolerate better prolonged hypoxia condition than males, and E2/ERβ treatment could be a potential therapy to prevent hypoxia-induced heart damage.”

IGF-IIR plays important roles as a key regulator in myocardial pathological hypertrophy and apoptosis, which subsequently lead to heart failure. Salvia miltiorrhiza Bunge (Danshen) is a traditional Chinese medicinal herb used to treat cardiovascular diseases. Tanshinone IIA is an active compound in Danshen and is structurally similar to 17[Formula: see text]-estradiol (E[Formula: see text]. However, whether tanshinone IIA improves cardiomyocyte survival in pathological hypertrophy through estrogen receptor (ER) regulation remains unclear. This study investigates the role of ER signaling in mediating the protective effects of tanshinone IIA on IGF-IIR-induced myocardial hypertrophy. Leu27IGF-II (IGF-II analog) was shown in this study to specifically activate IGF-IIR expression and ICI 182,780 (ICI), an ER antagonist used to investigate tanshinone IIA estrogenic activity. We demonstrated that tanshinone IIA significantly enhanced Akt phosphorylation through ER activation to inhibit Leu27IGF-II-induced calcineurin expression and subsequent NFATc3 nuclear translocation to suppress myocardial hypertrophy. Tanshinone IIA reduced the cell size and suppressed ANP and BNP, inhibiting antihypertrophic effects induced by Leu27IGF-II. The cardioprotective properties of tanshinone IIA that inhibit Leu27IGF-II-induced cell hypertrophy and promote cell survival were reversed by ICI. Furthermore, ICI significantly reduced phospho-Akt, Ly294002 (PI3K inhibitor), and PI3K siRNA significantly reduced the tanshinone IIA-induced protective effect. The above results suggest that tanshinone IIA inhibited cardiomyocyte hypertrophy, which was mediated through ER, by activating the PI3K/Akt pathway and inhibiting Leu27IGF-II-induced calcineurin and NFATC3. Tanshinone IIA exerted strong estrogenic activity and therefore represented a novel selective ER modulator that inhibits IGF-IIR signaling to block cardiac hypertrophy.

Aberrant expression of leucine zipper- and sterile ɑ motif-containing kinase (ZAK) observed in pathological human myocardial tissue is associated with the progression and elevation of hypertrophy. Our previous reports have correlated high levels of estrogen (E2) and abundant estrogen receptor (ER) α with a low incidence of pathological cardiac-hypertrophy and heart failure in the premenopause female population. However, the effect of elevated ERβ expression is not well known yet. Therefore, in this study, we have analyzed the cardioprotective effects and mechanisms of E2 and/or ERβ against ZAK overexpression-induced cellular hypertrophy. We have used transient transfection to overexpress ERβ into the ZAK tet-on H9c2 cells that harbor the doxycycline-inducible ZAK plasmid. The results show that ZAK overexpression in H9c2 cells resulted in hypertrophic effects, which was correlated with the upregulation of p-JNK and p-p38 MAPKs and their downstream transcription factors c-Jun and GATA-4. However, ERβ and E2 with ERβ overexpressions totally suppressed the effects of ZAK overexpression and inhibited the levels of p-JNK, p-p38, c-Jun, and GATA-4 effectively. Our results further reveal that ERβ directly binds with ZAK under normal conditions; however, ZAK overexpression reduced the association of ZAK-ERβ. Interestingly, increase in ERβ and E2 along with ERβ overexpression both enhanced the binding strengths of ERβ and ZAK and reduced the ZAK protein level. ERβ overexpression also suppressed the E3 ligase-casitas B-lineage lymphoma (CBL) and attenuated CBL-phosphoinositide 3-kinase (PI3K) protein association to prevent PI3K protein degradation. Moreover, ERβ and/or E2 blocked ZAK nuclear translocation via the inhibition of small ubiquitin-like modifier (SUMO)-1 modification. Taken together, our results further suggest that ERβ overexpression strongly suppresses ZAK-induced cellular hypertrophy and myocardial damage.

Cardiomyopathy involves changes in myocardial ultrastructure and cardiac hypertrophy. Angiotensin II (AngII) has previously been shown to stimulate the expression of IGF-2 and IGF-2R in H9c2 cardiomyoblasts and increase of blood pressure, and cardiac hypertrophy. Estrogen receptors (ERs) exert protective effects, such as anti-hypertrophy in cadiomyocytes. Tanshinone IIA (TSN), a main active ingredient from a Chinese medical herb, Salvia miltiorrhiza Bunge (Danshen), was shown to protect cardiomyocytes hypertrophy by different stress signals. We aimed to investigate whether TSN protected H9c2 cardiomyocytes from AngII-induced activation of IGF-2R pathway and hypertrophy by mediating through ERs. AngII resulted in H9c2 cardiomyoblast hypertrophy and increased inflammatory molecular markers. These were down-regulated by TSN via estrogen receptors. AngII resulted in elevation in MAPKs, IGF-2R and hypertrophic protein markers. These, again, were reduced by addition of the phytoestrogen with activation of ERs. Finally, AngII induced phosphorylation of heat shock factor-1 (HSF1) and decreased sirtuin-1 (SIRT1). In addition, AngII also caused an increase in distribution of IGF-2R molecules on cell membrane. In contrast, TSN reduced HSF1 phosphorylation and cell surface IGF-2R while elevating SIRT1 via ERs. TSN was capable of attenuating AngII-induced IGF-2R pathway and hypertrophy through ERs in H9c2 cardiomyoblast cells.

Background Doxorubicin (Dox) is an effective anticancer agent. However, its effectiveness is limited by its cardiotoxic effects. It has also been reported that the mitogen-activated protein kinase family and NF-κB can be activated by Dox treatment. DATS has been shown to be a potent antioxidant with cardioprotective effects. We investigate whether Dox induces cardiac apoptosis through JNK- and ERK-dependent NF-κB upregulation that can be reduced by DATS treatment. Methods and Material H9c2 cells were treated with 0.5–1.5 μM Dox for 24 hours. Dox promoted apoptosis and ROS generation and inhibited viability in a dose-dependent manner. Then, the phosphorylation levels of JNK, ERK, and NF-κB evaluated by western blot were elevated. We used inhibitors of JNK, ERK, and NF-κB to determine which of these proteins were involved in Dox-induced apoptosis. Furthermore, Dox-exposed cells were treated with DATS at doses of 1, 5, and 10 μM, and the data demonstrated that ROS generation and apoptotic proteins were decreased and that ERK and NF-κB were downregulated in a dose-dependent manner. Additionally, six-week-old rats were divided into three groups (n = 6 per group) designed as an eight-week study. Normal, Dox (at dose 3.75 mg/kg by ip) administered with or without DATS (at dose 40 mg/kg by gavage) treatment groups. The results indicate that cardiac dysfunction, apoptosis, and JNK, ERK, and NF-κB activation by Dox were reversed by treatment with DATS. Conclusion DATS appears to suppress Dox-induced cardiomyocyte apoptosis by inhibiting NADPH oxidase-related ROS production and the downstream JNK/ERK/NF-κB signaling pathway; DATS may possess clinical therapeutic potential by blocking Dox-induced cardiotoxicity.

Estrogen receptor α (ERα) and estrogen receptor β (ERβ) play important roles in cardiovascular disease (CVD) prevention. Recently, these estrogen receptors were reconsidered as an important treatment target of obesity leading to CVD. In this study, 17β-estradiol (17β-E) replacement therapy applied to high-fat diet-induced obese C57B male mice and ovariectomized (OVX) rats were evaluated, and the protective effects against high-fat diet-induced obesity were assessed in C57B mouse hearts. The results showed that 17β-E treatment activated both ERα and ERβ, and ERβ levels increased in a dose-dependent manner in high-fat diet C57B mouse cardiomyocytes following 17β-E treatment. Notably, an almost 16% reduction in body weight was observed in the 17β-E-treated (12 μg/kg/day for 60 days) high-fat diet-induced obese C57B male mice. These results suggested that 17β-E supplements may reduce CVD risk due to obesity.

Background The goal of this study is to determine if salidroside has protective effects on hypoxia-induced cardiac widely dispersed apoptosis in mice with severe sleep apnea model. Methods Sixty-four C57BL/6J mice 5–6months of age were divided into four groups, i.e. Control group (21% O 2 , 24h per day, 8weeks, n =16); Hypoxia group (Hypoxia: 7% O 2 60s, 20% O 2 alternating 60s, 8h per day, 8weeks, n =16); and Hypoxia+S10 and Hypoxia+S30 groups (Hypoxia for 1st 4weeks, hypoxia pretreated 10mg/kg and 30mg/kg salidroside by oral gavage per day for 2nd 4weeks, n =16 and 16). The excised hearts from four groups were measured by the heart weight index, H&E staining, TUNEL-positive assays and Western blotting. Results TUNEL-positive apoptotic cells in mice heart were less in Hypoxia+S10 and Hypoxia+S30 than those in the Hypoxia group. Compared with Hypoxia, the protein levels of Fas ligand, Fas death receptors, Fas-Associated Death Domain (FADD), activated caspase 8, and activated caspase 3 (Fas pathways) were decreased in Hypoxia+S10 and Hypoxia+S30. In the mitochondria pathway, the protein levels of BcLx, Bcl2, and Bid (anti-apoptotic Bcl2 family) in Hypoxia+S10 and Hypoxia+S30 were more than those in Hypoxia. The protein levels of Bax, t-Bid, activated caspase 9, and activated caspase 3 were less in Hypoxia+S10 and Hypoxia+S30 than those in hypoxia. Conclusions Our findings suggest that salidroside has protective effects on chronic intermittent hypoxia-induced Fas-dependent and mitochondria-dependent apoptotic pathways in mice hearts.

Exposure to tobacco smoke has epidemiologically been linked to the occurrence of cardiovascular disease among nonsmokers but the associated molecular events are not well elucidated yet. When Sprague Dawley rats were exposed to second-hand tobacco cigarette smoke twice a day for a 30 days period at an exposure rate of 10 cigarettes/30 min, they showed adverse effects including reduced left ventricle weight, increased cardiac damages, deteriorated cardiac features, and cardiac fibrosis. Exposure to second-hand smoking (SHS) increased the molecular markers of cardiac fibrosis such as urokinase plasminogen activator and matrix metallopeptidases. The modulations in the protein levels were led by the activation of extracellular signal-regulated kinases (ERK1/2), the transcription factor-specificity protein 1 (SP1), and the fibrogenic master switch-connective for epithelial-mesenchymal transition tissue growth factor there by indicating their effective role in SHS-induced myocardial infraction. Dilong, an edible earthworm extract used in Chinese medicine and its bioactive fibrinolytic enzyme product-lumbrokinase, when administered in rats, restricted the SHS exposure induced cardiac fibrosis and provided cardio-protection. The results show that lumbrokinase and dilong administration can efficiently prevent epidemiological incidence of cardiac disease among SHS-exposed nonsmokers.

Our previous results have indicated that Akt mediates 17β-estradiol (E₂) and/or estrogen receptor α (ERα) to inhibit lipopolysaccharide (LPS)-induced JNK activity, tumor necrosis factor α (TNFα) protein expression, and exhibits cardioprotective effects. Toll-like receptor 4 (TLR4) mRNAs often contain AU-rich elements (AREs) in their 3'-untranslated regions (3'UTR) which have a high affinity for RNA-binding proteins. It is not known whether E₂ and ERα affect TLR4 mRNA stability and TLR4 protein expression through regulating the RNA-binding proteins, human antigen R (HuR), tristetraprolin (TTP) and AU-binding factor 1 (AUF-1) in myocardial cells. Therefore, we investigated if the LPS in- duces these RNA-binding proteins to regulate TLR4 mRNAs of cardiomyocytes, and whether the E₂/ERα reduces the TLR4 mRNA stability induced by LPS through the inhibition of RNA-binding protein expression. Using a doxycycline (Dox)-induced Tet-On ERα H9c2 myocardic cell model, we also aimed to identify whether E₂ and/or ERα regulate LPS-induced TLR4 mRNA stability. The results of Western blotting and reverse transcription-PCR assays demonstrated that LPS significantly in- creased the level of cytoplasmic HuR protein and the stability of TLR4 mRNA, and farther induced TLR4 protein expression in H9c2 cells, an effect mediated through the JNK pathway. Interestingly, E₂ and/or ERα decreased the cytoplasmic HuR protein level and TLR4 mRNA stability, and farther decreased the level of TLR4 protein induced by LPS in H9c2 cardiomyoblast cells. Therefore, LPS triggered HuR expression which led to enhanced TLR4 mRNA and upregulated TLR4 expression through JNK1/2 in myocardial cells.

Cardiomyocyte hypertrophy is an adaptive response of the heart to various types of stress. During the period of stress accumulation, the transition from physiological hypertrophy to pathological hypertrophy results in the promotion of heart failure. Gelsolin (GSN) is a member of the actin-binding proteins, which regulate dynamic actin filament organization by severing and capping. Moreover, GSN also regulates cell morphology, differentiation, movement, and apoptosis. In this study, we used H9c2 and H9c2-GSN stable clones in an attempt to understand the mechanisms of GSN overexpression in cardiomyocytes. These data showed that the overexpression of GSN in H9c2-induced cardiac hypertrophy and increased the pathological hypertrophy markers atrial natriuretic peptide brain natriuretic peptide. Furthermore, we found that E-cadherin expression decreased with the overexpression of GSN in H9c2, but β-catenin expression increased. These data presume that the cytoskeleton is loose. Further, previous studies show that the mitogen-activated protein kinase pathway can induce cardiac hypertrophy. Our data showed that p-p38 expression increased with the overexpression of GSN in H9c2, and the transcription factor p-GATA4 expression also increased, suggesting that the overexpression of GSN in H9c2-induced cardiac hypertrophy seemed to be regulated by the p38/GATA4 pathway. Moreover, we used both the p38 inhibitor (SB203580) and GSN siRNA to confirm our conjecture. We found that both of these factors significantly suppressed gelsolin-induced cardiac hypertrophy through p38/GATA4 signaling pathway. Therefore, we predict that the gene silencing of GSN and/or the downstream blocking of GSN along the p38 pathway could be applied to ameliorate pathological cardiac hypertrophy in the future.

Cardiovascular diseases have a high prevalence worldwide and constitute the leading causes of mortality. Recently, malfunctioning of &beta, catenin signaling has been addressed in hypertensive heart condition. Ang-II is an important mediator of cardiovascular remodeling processes which not only regulates blood pressure but also leads to pathological cardiac changes. However, the contribution of Ang-II/&beta, catenin axis in hypertrophied hearts is ill-defined. Employing in vitro H9c2 cells and in vivo spontaneously hypertensive rats (SHR) cardiac tissue samples, western blot analysis, luciferase assays, nuclear-cytosolic protein extracts, and immunoprecipitation assays, we found that under hypertensive condition &beta, catenin gets abnormally induced that co-activated LEF1 and lead to cardiac hypertrophy changes by up-regulating the IGF-IIR signaling pathway. We identified putative LEF1 consensus binding site on IGF-IIR promoter that could be regulated by &beta, catenin/LEF1 which in turn modulate the expression of cardiac hypertrophy agents. This study suggested that suppression of &beta, catenin expression under hypertensive condition could be exploited as a clinical strategy for cardiac pathological remodeling processes.

This study shows that the ECM degradation-associated pathway, including uPA and tPA and the downstream MMP-2/-9 protein, was significantly suppressed in HA22T cells treated with a Zanthoxylum avicennae extract (YBBE). The endogenous inhibitors, including TIMP-1/-2 and PAI-1, were enhanced in HA22T cells by the YBBE treatment. The expression of MMP-2/-9 and TIMP-1/-2 was respectively assessed by using RT-PCR and a zymography assay. The mRNA levels and enzymatic activity of MMP-2/-9 were down-regulated by the YBBE treatment in a dose-dependent manner, while the TIMP-1/-2 levels were conversely markedly increased. The PP2A siRNA or PP2A inhibitor totally reversed the YBBE effects, confirming the essential role of PP2A in YBBE inhibiting the HA22T cell migration and invasion effects. Xenografted animal experiments on nude mice demonstrated similiar results to the in vitro system. Both the in vitro and in vivo models clearly demonstrate that YBBE inhibited the highly metastatic HA22T liver cancer cell migration and invasion effects through PP2A activation.

Q10 is a powerful antioxidant often used in medical nutritional supplements for cancer treatment. This study determined whether Q10 could effectively prevent cardio-toxicity caused by doxorubicin treatment. Four week old SD rats were segregated into groups namely control, doxorubicin group (challenged with doxorubicin), Dox + Q10 group (with doxorubicin challenge and oral Q10 treatment), and Q10 group (with oral Q10 treatment). Doxorubicin groups received IP doxorubicin (2.5 mg/kg) every 3 days and Q10 groups received Q10 (10 mg/kg) every day. Three weeks of doxorubicin challenge caused significant reduction in heart weight, disarray in cardiomyocyte arrangement, elevation of collagen accumulation, enhancement of fibrosis and cell death associated proteins, and inhibition of survival proteins. However, Q10 effectively protected cardiomyocytes and ameliorated fibrosis and cell death induced by doxorubicin. Q10 is, therefore, evidently a potential drug to prevent heart damage caused by doxorubicin. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 679-689, 2017.

A retained fractured segment of an intravascular ultrasound catheter in the coronary artery during percutaneous coronary intervention is a rare occurrence. We describe our experience with successful retrieval of a fractured IVUS catheter fragment in a previously stented left anterior descending artery using a distal embolic protection device.

During hypoxia, gene expression is altered by various transcription factors. Insulin-like growth factor-II (IGF2) is known to be induced by hypoxia, which binds to IGF2 receptor IGF2R that acts like a G protein-coupled receptor, might cause pathological hypertrophy or activation of the mitochondria-mediated apoptosis pathway. Cyclic adenosine monophosphate (cAMP) responsive element-binding protein (CREB) is central to second messenger-regulated transcription and plays a critical role in the cardiomyocyte survival pathway. In this study, we found that IGF2R level was enhanced in H9c2 cardiomyoblasts exposed to hypoxia in a time-dependent manner but was down-regulated by CREB expression. The over-expression of CREB in H9c2 cardiomyoblasts suppressed the induction of hypoxia-induced IGF2R expression levels and reduced cell apoptosis. Gel shift assay results further indicated that CREB binds to the promoter sequence of IGF2R. With a luciferase assay method, we further observed that CREB represses IGF2R promoter activity. These results suggest that CREB plays an important role in the inhibition of IGF2R expression by binding to the IGF2R promoter and further suppresses H9c2 cardiomyoblast cell apoptosis induced by IGF2R signaling under hypoxic conditions.

Exposure to second-hand tobacco smoke (SHS) has been epidemiologically linked to heart disease among non-smokers. However, the molecular mechanism behind SHS-induced cardiac disease is not well known. This study found that SD rats exposed to cigarette smoke at a dose of 10 cigarettes for 30 min twice a day for 1 month had a reduced left ventricle-to-tibia length ratio (mg/mm), increased cardiomyocyte apoptosis by TUNEL assay and a wider interstitial space by H&E staining. However, lumbrokinase and dilong both reversed the effects of SHS. Western blotting demonstrated significantly increased expression of the pro-apoptotic protein caspase-3 in the hearts of the rats exposed to SHS. Elevated protein expression levels of Fas, FADD and the apoptotic initiator activated caspase-8, a molecule in the death-receptor-dependent pathway, coupled with increased t-Bid and apoptotic initiator activated caspase-9 were found. Molecules in the mitochondria-dependent pathway, which disrupts mitochondrial membrane potential, were also found in rats exposed to SHS. These factors indicate myocardial apoptosis. However, treatment with lumbrokinase and dilong inhibited SHS-induced apoptosis. Regarding regulation of the survival pathway, we found in western blot analysis that cardiac protein expression of pAkt, Bcl2, and Bcl-xL was significantly down-regulated in rats exposed to SHS. These effects were reversed with lumbrokinase and dilong treatment. The effects of SHS on cardiomyocytes were also found to be mediated by the Fas death receptor-dependent apoptotic pathway, an unbalanced mitochondria membrane potential and decreased survival signaling. However, treatment with both lumbrokinase and dilong inhibited the effects of SHS. Our data suggest that lumbrokinase and dilong may prevent heart disease in SHS-exposed non-smokers.

Background: Secondhand smoke (SHS) exposure is associated with increased risk of cardiovascular disease. Aging is a physiological process that involves progressive impairment of normal heart functions due to increased vulnerability to damage. This study examines secondhand smoke exposure in aging rats to determine the age-related death-survival balance. Methods: Rats were placed into a SHS exposure chamber and exposed to smog. Old age male Sprague-Dawley rats were exposed to 10 cigarettes for 30 min, day and night, continuing for one week. After 4 weeks the rats underwent morphological and functional studies. Left ventricular sections were stained with hematoxylin-eosin for histopathological examination. TUNEL detected apoptosis cells and protein expression related death and survival pathway were analyzed using western blot. Results: Death receptor-dependent apoptosis upregulation pathways and the mitochondria apoptosis proteins were apparent in young SHS exposure and old age rats. These biological markers were enhanced in aging SHS-exposed rats. The survival pathway was found to exhibit compensation only in young SHS-exposed rats, but not in the aging rats. Further decrease in the activity of this pathway was observed in aging SHS-exposed rats. TUNEL apoptotic positive cells were increased in young SHS-exposed rats, and in aging rats with or without SHS-exposure. Conclusions: Aging reduces IGF-I compensated signaling with accelerated cardiac apoptotic effects from second-hand smoke.

Cirrhotic cardiomyopathy (CCM) is a common cardiac dysfunction in patients waiting for orthotopic liver transplantation (OLT). Carbon tetrachloride (CCl₄) intraperitoneal (IP) injection has been reported as successful in a cirrhosis-induced CCM model. In this work, we used the same assay for CCM induction using CCl₄ (0.2 mg/kg) IP injection twice per day for 14 days during the cardiac protection drugs treatment process. The cardiac protection drugs were silymarin (100 mg/kg/day), baicalein (30 mg/kg/day), San Huang Shel Shin Tang (SHSST, 30 mg/kg/day) and β-cyclodextrin modified SHSST (SHSSTc, 30 mg/kg/day and 300 mg/kg/day). After 4 weeks of treatment, the SHSSTc cardiac protection effects were determined through activation of the IGF1R cell survival pathway and inhibition of Fas-FADD death domain induced-apoptosis. SHSSTc cardiac protection was enhanced through β-cyclodextrin modification, which increased bio-availability, and displayed stronger protective effects than silymarin and baicalein, both of which are well-known liver protection drugs. Thus, SHSSTc might provide the best therapeutic benefit in CCM treatment.

Hypercholesterol diets are the major causes of cardiac hypertrophy and various cardiac disorders. The purpose of this study is to evaluate the effects of garlic oil on cardiac hypertrophy induced by hypercholesterol diets. Golden Syrian hamsters were fed with 2% cholesterol or 2% cholesterol plus 1% garlic oil for 2 months. Heart architecture changes were measured by hematoxylin-eosin staining and the molecular mechanism was determined by western blotting. Garlic oil reduced whole-heart weight to bone weight ratio, and left ventricle weight to bone weight ratio in the cholesterol-fed group. Moreover, the garlic oil group showed significantly reduced interleukin-6, phosphorylated (p)-extracellular signal-regulated kinase-5, p-mitogen-activated protein kinase-5, calcineurin, nuclear transcription factor of nuclear factor of activated T-cells-3 and p-GATA binding protein 4 when compared with the cholesterol group. However, no changes were observed in gp-130, signal transducer and activator of transcription-3, p-P38 and p-Jun N-terminal kinases protein levels in all groups. The results show that garlic oil may be useful in the treatment of hypertrophy-associated cardiovascular diseases.

To test the hypothesis that syndrome X is a systemic vascular disorder, technetium-99m ethyl cysteinate dimer (Tc-99m ECD) brain single photon emission computed tomography (SPECT) was used to detect abnormal regional cerebral blood flow (rCBF) in 30 patients with syndrome X. These patients were separated into group 1, 20 patients with definite myocardial perfusion defects diagnosed by thallium-201 (Tl-201) myocardial perfusion SPECT; and group 2, 10 patients without any myocardial perfusion defects. Tc-99m ECD brain SPECT demonstrated hypoperfusion brain lesions in 95% (19/20) and 20% (2/10) of patients in groups 1 and 2, respectively. This difference in the cidence between the two groups was significant. In group 1 and 2 patients, parietal lobes were the most common hypoperfusion areas, while the cerebellum was the least common hypoperfusion area of the brain. Syndrome X is a systemic vascular disorder with a high incidence of hypoperfusion lesions of the brain based on the findings of Tc-99m ECD brain SPECT, and is usually coincident with myocardial defects based on the Tl-201 myocardial perfusion SPECT findings.

Hypercholesterol diets are the major causes of cardiac hypertrophy and various cardiac disorders. The purpose of this study is to evaluate the effects of garlic oil on cardiac hypertrophy induced by hypercholesterol diets. Golden Syrian hamsters were fed with 2% cholesterol or 2% cholesterol plus 1% garlic oil for 2 months. Heart architecture changes were measured by hematoxylin-eosin staining and the molecular mechanism was determined by western blotting. Garlic oil reduced whole-heart weight to bone weight ratio, and left ventricle weight to bone weight ratio in the cholesterol-fed group. Moreover, the garlic oil group showed significantly reduced interleukin-6, phosphorylated (p)-extracellular signal-regulated kinase-5, p-mitogen-activated protein kinase-5, calcineurin, nuclear transcription factor of nuclear factor of activated T-cells-3 and p-GATA binding protein 4 when compared with the cholesterol group. However, no changes were observed in gp-130, signal transducer and activator of transcription-3, p-P38 and p-Jun N-terminal kinases protein levels in all groups. The results show that garlic oil may be useful in the treatment of hypertrophy-associated cardiovascular diseases.

Only very limited information regarding the protective effects of the superoxide anion scavenger on chronic intermittent hypoxia-induced cardiac apoptosis is available. The purpose of this study is to evaluate the effects of the superoxide anion scavenger on cardiac apoptotic and prosurvival pathways in rats with sleep apnea. Forty-two Sprague-Dawley rats were divided into three groups, rats with normoxic exposure (Control, 21% O2, 1 mo), rats with chronic intermittent hypoxia exposure (Hypoxia, 3-7% O2 vs. 21% O2 per 40 s cycle, 8 h per day, 1 mo), and rats with pretreatment of the superoxide anion scavenger and chronic intermittent hypoxia exposure (Hypoxia-O2−-Scavenger, MnTMPyP pentachloride, 1 mg/kg ip per day; 3–7% O2 vs. 21% O2 per 40 s cycle, 8 h per day, 1 mo) at 5–6 mo of age. After 1 mo, the protein levels and apoptotic cells of excised hearts from three groups were measured by Western blotting and terminal deoxynucleotide transferase-mediated dUTP nick end labeling (TUNEL) assay. The superoxide anion scavenger decreased hypoxia-induced myocardial architecture abnormalities, left ventricular hypertrophy, and TUNEL-positive apoptosis. The superoxide anion scavenger decreased hypoxia-induced Fas ligand, Fas death receptors, Fas-associated death domain (FADD), activated caspase-8, and activated caspase-3 (Fas-dependent apoptotic pathway) as well as Bad, activated caspase-9 and activated caspase-3 (mitochondria-dependent apoptotic pathway), endonuclease G (EndoG), apoptosis-inducing factor (AIF), and TUNEL-positive apoptosis. The superoxide anion scavenger increased IGF-1, IGF-1R, p-PI3k, p-Akt, p-Bad, Bcl-2, and Bcl-xL (survival pathway). Our findings imply that the superoxide anion scavenger might prevent cardiac Fas-mediated and mitochondrial-mediated apoptosis and enhance the IGF-1-related survival pathway in chronic intermittent hypoxia. The superoxide anion scavenger may prevent chronic sleep apnea-enhanced cardiac apoptotic pathways and enhances cardiac survival pathways.