The water extract of Amydrium sinense (Engl.) H. Li ameliorates Isoproterenol-induced cardiac hypertrophy through inhibiting the NF-κB signaling pathway.

OBJECTIVE: Pathologic cardiac hypertrophy (PCH) is a precursor to heart failure. Amydrium sinense (Engl.) H. Li (AS), a traditional Chinese medicinal plant, has been extensively utilized to treat chronic inflammatory diseases. However, the therapeutic effect of ASWE on PCH and its underlying mechanisms are still not fully understood. METHODS: A cardiac hypertrophy model was established by treating C57BL/6 J mice and neonatal rat cardiomyocytes (NRCMs) in vitro with isoprenaline (ISO) in this study. The antihypertrophic effects of AS water extract (ASWE) on cardiac function, histopathologic manifestations, cell surface area and expression levels of hypertrophic biomarkers were examined. Subsequently, the impact of ASWE on inflammatory factors, p65 nuclear translocation and NF-κB activation was investigated to elucidate the underlying mechanisms. RESULTS: In the present study, we observed that oral administration of ASWE effectively improved ISO-induced cardiac hypertrophy in mice, as evidenced by histopathological manifestations and the expression levels of hypertrophic markers. Furthermore, the in vitro experiments demonstrated that ASWE treatment inhibited cardiac hypertrophy and suppressed inflammation response in ISO-treated NRCMs. Mechanically, our findings provided evidence that ASWE suppressed inflammation response by repressing p65 nuclear translocation and NF-κB activation. ASWE was found to possess the capability of inhibiting inflammation response and cardiac hypertrophy induced by ISO. CONCLUSION: To sum up, ASWE treatment was shown to attenuate ISO-induced cardiac hypertrophy by inhibiting cardiac inflammation via preventing the activation of the NF-kB signaling pathway. These findings provided scientific evidence for the development of ASWE as a novel therapeutic drug for PCH treatment.

Brassica oleracea L. extract ameliorates isoproterenol-induced myocardial injury by regulating HIF-1α-mediated glycolysis.

Brassica oleracea L. (BO) is an important vegetable with proven health benefits. This study aimed to elucidate the constituents of BO leaf extract (BOE) and evaluate its effect on myocardial injury. For this purpose, the constituents of BOE were identified using ultra-high performance liquid chromatography with quadrupole time-of- flight mass spectrometry, and 26 compounds were determined, including glucosinolates, sulfur compounds, alkaloids, phenolic acids, flavones, and two other kinds of compounds. The effects of BOE on myocardial cells were evaluated using isoproterenol (ISO)-treated H9C2 cells and Wistar rats, and the results revealed that BOE could inhibit cardiomyocyte hypertrophy and reduce the levels of B-type natriuretic peptide, nitric oxide, reactive oxygen species, lactic acid, and pyruvic acid. Meanwhile, BOE could increase the levels of mitochondrial membrane potential. Moreover, BOE could reduce the levels of apoptosis- and glycolysis-related proteins. Taken together, our data demonstrated that BOE treatment could alleviate ISO-induced myocardial cell injury by downregulating apoptosis and glycolysis signals.

Regulation of Na+-K+-ATPase leads to disturbances of isoproterenol-induced cardiac dysfunction via interference of Ca2+-dependent cardiac metabolism.

Reductions in Na+-K+-ATPase (NKA) activity and expression are often observed in the progress of various reason-induced heart failure (HF). However, NKA α1 mutation or knockdown cannot cause spontaneous heart disease. Whether the abnormal NKA α1 directly contributes to HF pathogenesis remains unknown. Here, we challenge NKA α1+/- mice with isoproterenol to evaluate the role of NKA α1 haploinsufficiency in isoproterenol (ISO)-induced cardiac dysfunction. Genetic knockdown of NKA α1 accelerated ISO-induced cardiac cell hypertrophy, heart fibrosis, and dysfunction. Further studies revealed decreased Krebs cycle, fatty acid oxidation, and mitochondrial OXPHOS in the hearts of NKA α1+/- mice challenged with ISO. In ISO-treated conditions, inhibition of NKA elevated cytosolic Na+, further reduced mitochondrial Ca2+ via mNCE, and then finally down-regulated cardiac cell energy metabolism. In addition, a supplement of DRm217 alleviated ISO-induced heart dysfunction, mitigated cardiac remodeling, and improved cytosolic Na+ and Ca2+ elevation and mitochondrial Ca2+ depression in the NKA α1+/- mouse model. The findings suggest that targeting NKA and mitochondria Ca2+ could be a promising strategy in the treatment of heart disease.

Sibjotang Protects against Cardiac Hypertrophy In Vitro and In Vivo.

Cardiac hypertrophy is developed by various diseases such as myocardial infarction, valve diseases, hypertension, and aortic stenosis. Sibjotang (, Shizaotang, SJT), a classic formula in Korean traditional medicine, has been shown to modulate the equilibrium of body fluids and blood pressure. This research study sought to explore the impact and underlying process of Sibjotang on cardiotoxicity induced by DOX in H9c2 cells. In vitro, H9c2 cells were induced by DOX (1 µM) in the presence or absence of SJT (1-5 µg/mL) and incubated for 24 h. In vivo, SJT was administrated to isoproterenol (ISO)-induced cardiac hypertrophy mice (n = 8) at 100 mg/kg/day concentrations. Immunofluorescence staining revealed that SJT mitigated the enlargement of H9c2 cells caused by DOX in a dose-dependent way. Using SJT as a pretreatment notably suppressed the rise in cardiac hypertrophic marker levels induced by DOX. SJT inhibited the DOX-induced ERK1/2 and p38 MAPK signaling pathways. In addition, SJT significantly decreased the expression of the hypertrophy-associated transcription factor GATA binding factor 4 (GATA 4) induced by DOX. SJT also decreased hypertrophy-associated calcineurin and NFAT protein levels. Pretreatment with SJT significantly attenuated DOX-induced apoptosis-associated proteins such as Bax, caspase-3, and caspase-9 without affecting cell viability. In addition, the results of the in vivo study indicated that SJT significantly reduced the left ventricle/body weight ratio level. Administration of SJT reduced the expression of hypertrophy markers, such as ANP and BNP. These results suggest that SJT attenuates cardiac hypertrophy and heart failure induced by DOX or ISO through the inhibition of the calcineurin/NFAT/GATA4 pathway. Therefore, SJT may be a potential treatment for the prevention and treatment of cardiac hypertrophy that leads to heart failure.

Experimental research on the evaluation of left ventricular systolic function by layered speckle tracking before and after berberine treatment in a cardiac hypertrophy rat model.

Background: To evaluate the effect of berberine (BBR) intervention on left ventricular hypertrophy and systolic function in rats by ultrasound layered strain imaging and cardiac hypertrophy model. Methods: Eighty healthy male Sprague-Dawley (SD) rats were randomly divided into four groups: group A (normal saline control group), group B [isoproterenol (ISO) induced model group], group C (BBR hydrochloride 5 mg/kg + ISO group) and group D (BBR hydrochloride 10 mg/kg + ISO group). Echocardiography was performed on days 1, 7 and 14, respectively. The myocardial tissue was taken for pathological examination. The key proteins of Rho/ROCK signaling pathway were quantified by immunohistochemical staining. Results: On day 7, compared with group A, peripheral strain values of the subendocardium and middle myocardium of rats in groups B, C and D were significantly decreased. The absolute value of circumferential strain (CS) in subendocardium and middle myocardium in group B was significantly lower than that in groups C and D (-24.21 vs. -26.68 vs. -27.69; -14.90 vs. -16.48 vs. -17.69). Pathological results showed that compared with the myocardial cells in control group A, the myocardial cells in group B had significantly increased cross-sectional area, and obvious myocardial interstitial fibrosis. Compared with group B, BBR intervention reduced the deposition of fibrosis in groups C and D, group D was more obvious. Immunohistochemical results showed that compared with group A, the protein expression levels of ROCK, RhoA and Bax in groups B, C and D were significantly increased, while the protein expression levels of Bcl-2 were significantly decreased. Conclusions: Ultrasound layered strain imaging could evaluate the early left ventricular systolic function in isoprenaline-induced hypertrophy rat model. BBR might inhibit oxidative stress through the Rho/ROCK signaling pathway and slow down the progression of myocardial fibrosis after the formation of cardiac hypertrophy. This provides reference and direction for clinical decision-making and further research.

Shexiang Tongxin Dropping Pill Allieviates Heart Failure via Extracellula Matrix-Receptor Interaction Pathways Based on RNA-Seq Transcriptomics and Experimental Studies.

OBJECTIVE: To investigate the protective mechanisms of Chinese medicine Shexiang Tongxin Dropping Pills (STDP) on heart failure (HF). METHODS: Isoproterenol (ISO)-induced HF rat model and angiotensin II (Ang II)-induced neonatal rat cardiac fibroblast (CFs) model were used in the present study. HF rats were treated with and without STDP (3 g/kg). RNA-seq was performed to identify differentially expressed genes (DEGs). Cardiac function was evaluated by echocardiography. Hematoxylin and eosin and Masson's stainings were taken to assess cardiac fibrosis. The levels of collagen I (Col I) and collagen III (Col III) were detected by immunohistochemical staining. CCK8 kit and transwell assay were implemented to test the CFs' proliferative and migratory activity, respectively. The protein expressions of α-smooth muscle actin (α-SMA), matrix metalloproteinase-2 (MMP-2), MMP-9, Col I, and Col III were detected by Western blotting. RESULTS: The results of RNA-seq analysis showed that STDP exerted its pharmacological effects on HF via multiple signaling pathways, such as the extracellular matrix (ECM)-receptor interaction, cell cycle, and B cell receptor interaction. Results from in vivo experiments demonstrated that STDP treatment reversed declines in cardiac function, inhibiting myocardial fibrosis, and reversing increases in Col I and Col III expression levels in the hearts of HF rats. Moreover, STDP (6, 9 mg/mL) inhibited the proliferation and migration of CFs exposed to Ang II in vitro (P<0.05). The activation of collagen synthesis and myofibroblast generation were markedly suppressed by STDP, also the synthesis of MMP-2 and MMP-9, as well as ECM components Col I, Col III, and α-SMA were decreased in Ang II-induced neonatal rats' CFs. CONCLUSIONS: STDP had anti-fibrotic effects in HF, which might be caused by the modulation of ECM-receptor interaction pathways. Through the management of cardiac fibrosis, STDP may be a compelling candidate for improving prognosis of HF.

Melatonin Supplement Plus Exercise Effectively Counteracts the Challenges of Isoproterenol-Induced Cardiac Injury in Rats.

To explore the combined effects of exercise and melatonin supplement against the challenges of isoproterenol-induced cardiac oxidative stress and injury in rats., the expression of peroxisome proliferator-activated receptor gamma co-activator-1α (PGC-1α), mitochondrial biogenesis, and adenosine triphosphate (ATP) was up-regulated in cardiac muscle in normal rats and in a melatonin and exercise regimented group. Cardiac injury was induced by two subcutaneous injections of isoproterenol in the rats. The combination of exercise and melatonin supplement successfully counteracted the isoproterenol-induced cardiac injury, which is reflected by the improved hemodynamic parameters, reduction in oxidative stress markers, and cardiac injury serum markers (cardiac troponin-I and creatine kinase-MB). The cardiac tissue level of ATP, expression of PGC-1α and mitochondrial biogenesis-related genes, mitochondrial membrane potential, and the activities of typical antioxidants (glutathione, superoxide dismutase) were preserved, whereas the levels of reactive oxygen species, lipid peroxidation, and inflammatory cytokines were suppressed in the melatonin and exercise regimented (MEI) group compared to the group treated with isoproterenol alone. Furthermore, the expression of endoplasmic reticular stress- and apoptosis-related proteins (Bax, Bcl2, and caspase-3) was also effectively suppressed in the MEI group. Therefore, the present study suggests that melatonin supplement in combination with exercise prevents cardiac injury, possibly through the preservation of mitochondrial function and inhibition of oxidative stress in rats.

Curdione Relieved Isoproterenol-Induced Myocardial Damage through Inhibiting Oxidative Stress and Apoptosis.

Isoproterenol (ISO) is widely used to treat bronchial asthma, cardiogenic or septic shock, complete atrioventricular block, and cardiac arrest. However, it can also cause myocardial damage owing to infarct-like necrosis. Curdione, an extract of the Chinese herb Rhizoma Curcumae, has a variety of pharmacological activities, including cardioprotective effects. In this study, we investigated the protective effects of curdione and its underlying mechanisms in an ISO-induced myocardial injury model. Our results showed that curdione attenuated ISO-induced H9c2 cell proliferation inhibition and lactic dehydrogenase (LDH) release. Curdione ameliorated morphological damage and reduced the ISO-induced elevation of serum creatine kinase-MB isoenzyme (CK-MB) and LDH. Furthermore, curdione inhibited ISO-induced cell apoptosis, modulated the expression of Bcl-2 and Bax proteins, repealed the accumulation of ISO-induced reactive oxygen species (ROS), prevented mitochondrial dysfunction, and activated the Nrf2/SOD1/HO-1 signaling pathway. The above results show that curdione exerts a protective effect against ISO-induced myocardial damage by inhibiting apoptosis and oxidative stress, suggesting that curdione is a potential therapeutic strategy to prevent ISO-induced myocardial damage.

Artemisinin Attenuates Isoproterenol-induced Cardiac Hypertrophy via the ERK1/2 and p38 MAPK Signaling Pathways.

BACKGROUND: Artemisinin (ART) is mainly derived from Artemisia annua, a traditional Chinese medicinal plant, and has been found to affect cellular biochemical processes, such as proliferation, angiogenesis, and apoptosis, in addition to its antimalarial properties. However, its effect on cardiac hypertrophy and the underlying mechanisms remain unclear. OBJECTIVES: This study aimed to investigate the effect of ART on cardiac hypertrophy and explore its possible mechanisms. MATERIALS AND METHODS: A rat model was established by intraperitoneal injection of isoproterenol (ISO) for 3 days, and the degree of myocardial hypertrophy was compared among 5 groups: a control (CON) group, an ISO group, and groups treated with different doses of ART (7 mg/kg/d, 35 mg/kg/d, and 75 mg/kg/d). Echocardiography was used to evaluate cardiac function and structure. The cross-sectional area of cardiomyocytes was measured by hematoxylin and eosin (H&E) staining. The heart weight (HW), body weight (BW), and tail length were measured, and the HW/tail length ratio and the HW/BW ratio were calculated. H9c2 rat cardiomyocytes were cultured, and different amounts of ART were added 2 hours before ISO stimulation. Phalloidin staining was used to evaluate the degree of cell hypertrophy. The levels of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) were quantified in rat plasma and cell supernatant using enzyme-linked immunosorbent assay (ELISA), while the expression levels of p- ERK1/2, p-JNK, and p-p38 MAPK were assessed in the myocardium and H9c2 cells via western blot analysis. RESULTS: Intragastric administration of ART at a dosage of 35 mg/kg/d or over mitigated the early-stage cardiac hypertrophy induced by ISO in rats led to a reduction in left ventricular posterior wall diastolic thickness, interventricular septal thickness at diastole, lowered ANP and BNP levels, as well as a decrease in HW/tail length and HW/BW ratio. In vitro studies demonstrated that ART at a concentration of 100 µM inhibited ISO-mediated hypertrophy of H9c2 cells. The ISO group showed a higher p-ERK/GAPDH ratio and p-p38 MAPK/GAPDH ratio than the control group both in vivo and in vitro. Although the p-JNK/GAPDH ratio was increased in the ISO group, there was no statistical difference. The p-ERK/GAPDH and p-p38/GAPDH ratios were significantly lower in the ART group than in the ISO group. CONCLUSION: The mechanism of ART against cardiac hypertrophy was related to inhibition of the ERK1/2 and p38 MAPK signaling pathways.

Bergapten mediated inflammatory and apoptosis through AMPK/eNOS/AKT signaling pathway of isoproterenol-induced myocardial infarction in Wistar rats.

Bergapten (BeG) is explored for its anti-inflammatory and antioxidant properties. Myocardial infarction (MI) is reported to be one of the leading cardiovascular diseases characterized by mitochondrial dysfunction and apoptosis. The main purpose of this study is to assess the cardiopreventive effects of BeG (50 mg/kg) in isoproterenol (ISO)-induced MI in Wistar rats. The increased infarct size after ISO induction was reduced simultaneously on treatment with BeG. Similarly, augmented levels of cardiac biomarkers, namely cardiac troponin T, creatine kinase (CK), cardiac troponin I, and CK-MB were also suppressed by BeG. The increased rate of lipid hydroperoxides and thiobarbituric acid reactive substances owing to the oxidative stress caused by free radical generation in ISO-induced rats were also inhibited by BeG. Antioxidants reduce oxidative stress by scavenging free radicals. ISO induction reduces these antioxidant enzymes glutathione peroxidase, catalase, superoxide dismutase, and glutathione, and levels causing oxidative cardiac damage to the heart tissue. BeG supplementation improved these enzymes synthesis preventing potential damage to the myocardium. Inflammation caused by ISO pretreatment increased the secretion of proinflammatory cytokines in ISO-induced rats. Pretreatment with BeG suppressed these inflammatory cytokines to a normal level in ISO + BeG-treated rats. The histopathological examination of the morphological characteristics showed that the intensity of cardiac damage caused by ISO induction was less in BeG pretreated rats with less inflammatory cells and no necrosis. BeG also showed promising results in the molecular alteration of AMP-activated protein kinase/endothelial nitric oxide synthase/protein kinase B signaling molecules. These observations emphasize the cardioprotective effects of BeG and its potential use as a drug in the near future.

In vivo evaluation and molecular docking studies of Schinus molle L. fruit extract protective effect against isoproterenol-induced infarction in rats.

The aim of the current study was to assess the potential cardiopreventive effect of the methanolic extract of S. molle L. (MESM) on isoproterenol-induced infarction in rats. The biomolecules content was evaluated using HPLC-DAD-ESI-QTOF-MS/MS analysis. On the 29th and 30th days, two successive injections of isoproterenol (ISO) were given to Wistar rats to provoke myocardial infarction following pretreatment with either MESM (60 mg/kg b.w) or Pidogrel (Pid; 2 mg/kg b.w.). A total of sixteen phenolics were identified with masazino-flavanone as the most prevalent compound (1726.12 µg/g dm). Results showed that MESM offered cardioprevention by normalizing the ST segment and reducing the elevated cardiac risk parameters. The altered lipid biomarkers together with the plasma ionic levels were improved. Additionally, MESM inhibited the cardiac oxidative stress generated by ISO injection though enhancing antioxidant enzymes (GSH, CAT, SOD and GPX) which reduced lipid peroxidation and protein oxidation. MESM reduced myocardial apoptosis by significantly repressing mRNA expressions of Caspase-3 and Bax, with an upregulated Bcl-2 expression. Moreover, MESM reduced DNA fragmentation as well as the infarct size observed by TTC staining. In addition, MESM exhibited an antifibrotic effect by downregulating TGF-1ß expression and reducing collagen deposition in myocardial tissue, as confirmed by Trichrom Masson analysis. The histopathological findings revealed less muscle separation and fewer inflammatory cells in the ISO + MESM-treated rats. Results of the docking simulation indicated that catechin in MESM was inhibitory mainly due to hydrogen bonding interactions with PDI, ACE and TGF-ß1 proteins which could highlight the antithrombotic and antifibrotic capacity of MESM.

[Protective effect of ophiopogonin D against isoproterenol-induced cardiomyocyte injury and targets].

This study aims to unveil the effect of ophiopogonin D(OPD) on isoproterenol(ISO)-induced apoptosis of rat cardiomyocytes and the possible targets, which is expected to provide clues for further research on the myocardial protection of ophiopogonins. Cell count kit-8(CCK-8) assay was used to detect viability of cells treated with OPD and ISO, Western blot to examine the effect of OPD and ISO on the expression of endoplasmic reticulum stress-related Bip, Bax, Perk, ATF4, caspase-12, and CHOP, flow cytometry to determine cell apoptosis rate, and Hoechst 33258 and Tunel staining to observe cell apoptosis and morphological changes. In addition, the probe for calcium ion-specific detection was employed to investigate calcium ion release from the endoplasmic reticulum, and OPD-bond epoxy-activated agarose solid-phase microspheres were prepared and used as affinity matrix to capture OPD-binding target proteins in H9 c2 cell lysate. For the target proteins of OPD identified by high-resolution mass spectrometry, the related signal pathways were enriched and the potential targets of OPD against cardiomyocyte injury were discussed. The experimental result showed that 10 µmol·L~(-1) ISO can significantly induce the expression of endoplasmic reticulum stress-related proteins and promote cell apoptosis. Different concentration of OPD can prevent the damage of myocardial cells caused by ISO. According to mass spectrometry results, 19 proteins, including Fam129 a and Pdia6, were involved in multiple signaling pathways such as the unfolded protein reaction bound by the ERN1 sensor, tricarboxylic acid cycle, and Nrf2 signal transduction pathway. The above results indicate that OPD protects cardiomyocytes by regulating multiple signaling pathways of target proteins and affecting cell cycle progression.

Valencene post-treatment exhibits cardioprotection via inhibiting cardiac hypertrophy, oxidative stress, nuclear factor- κB inflammatory pathway, and myocardial infarct size in isoproterenol-induced myocardial infarcted rats; A molecular study.

The growing burden of myocardial infarction (MI) becomes a major global health issue that is accountable for considerable mortality worldwide. Hence, it is obligatory to develop a new treatment for MI having lesser side effects. Cardiac hypertrophy, oxidative stress, and inflammatory pathways play crucial roles in the pathogenesis of MI. This investigation established the anti-cardiac hypertrophic, antioxidant, anti-inflammatory, and myocardial infarct size limiting effects of valencene. Rats were induced MI by isoproterenol (100 mg/kg body weight) and then treated with valencene and cardiac sensitive markers, cardiac hypertrophy, oxidative stress, markers of inflammation, nuclear factor- κB inflammatory pathway, and myocardial infarct size was estimated/determined. The serum cardiac diagnostic markers, cardiac hypertrophy, conjugated dienes, markers of inflammation, pro-inflammatory cytokines, and myocardial infarct size were significantly (P < 0.05) increased by isoproterenol. Further, antioxidant enzymes and anti-inflammatory cytokine gene were significantly (P < 0.05) decreased in the heart. The 2, 3, 5-triphenyl tetrazolium chloride dye staining revealed a larger infarct size. Moreover, histological results of myocardial infarcted rat's cardiac tissue revealed separation of cardiac muscle fibers, necrosis, and inflammatory cells. Post-treatment with valencene (12 mg/kg body weight) orally, daily, for two weeks to isoproterenol-induced myocardial infarcted rats reversed all above said structural, biochemical, molecular, and histological parameters investigated, by its anti-cardiac hypertrophic, antioxidant, anti-inflammatory, and myocardial infarct size limiting effects. Thus, valencene is a potential candidate for inhibiting cardiac hypertrophy, oxidative stress, nuclear factor- κB inflammatory pathway, and myocardial infarct size and exhibited cardioprotection in MI.

Protective Effects of Sauropus Androgynus Leaf Extract against Isoproterenol Induced Cardiotoxicity.

The current research work focuses on the identification of cardioprotective effect of the ethanolic extract of Sauropus androgynus (EESA) leaves. Sauropus androgynus leaves are being utilized in folk and ayurvedic medicines in India to treat cardiovascular diseases like myocardial infraction, atherosclerosis, and venous thrombosis. However, the cardioprotective effects associated with the leaf extract of this plant has not yet been established. METHODS: The identification of cardioprotective effects of the ethanolic extract of Sauropus androgynus (EESA) leaves was performed using in vitro and in vivo models. The cell culture studies were performed using cardio myoblast cells (H9C2) and in vivo cardioprotective effects of EESA was assessed in albino wistar rats employing isoproterenol (ISO) as cardiotoxic agent. The animals were divided into six treatment groups and myocardial infraction was induced at 14th day followed by the treatment with therapeutic doses of EESA (100, 200 and 400 mg/kg) for next two days. Various biochemical and histopathological parameters were evaluated in animals kept under control and treatment groups. RESULTS: The in vitro cell line studies revealed a positive impact on H9C2 cells. The ethanolic extract of Sauropus androgynus depicted low toxicity on cardiomyoblast cells and significant proliferation was observed after treatment. The results from animal studies have shown 1.7 times reduction in serum LDH (151.9 ± 1.302) and CPK (237.6 ± 5.781) levels with EESA treated groups compared to toxic control. EESA also significantly increased the antioxidant enzyme levels, which are responsible for cardioprotective effects in animals. CONCLUSION: This research study reveals that EESA possess antioxidant activity and also provides a protective role against myocardial infarction induced by ISO. We conclude that EESA could be a potential candidate to prevent and treat cardiotoxic consequences of high catecholamine levels.

Wnt/ß-catenin antagonist pyrvinium rescues high dose isoproterenol induced cardiotoxicity in rats: Biochemical and immunohistological evidences.

The up-regulation of Wnt/ß-catenin pathway induces cardiac function abnormalities, hypertrophy, and fibrosis in diabetic hypertensive and pressure overload models. The present study investigates the cardioprotective effects of Wnt/ß-catenin inhibition on isoproterenol (ISO) induced cardiotoxicity in rats. ISO was administered at a dose of 85 mg/kg (s.c) for 2 days. Wnt/ß-catenin inhibitor pyrvinium (60 µg/kg, p.o) was given 2h prior and glibenclamide at a dose of 5 mg/kg; p.o, 2 h after ISO injection. Cardiac function parameters were assessed on isolated hearts by using automated Biopac apparatus. The ß-catenin transcription and expression was detected by RT-PCR technique and immunohistochemical method. Serum and cardiac tissue biochemical changes including cardiac troponin-I, CK-MB, LDH, anti-oxidant enzyme levels, inflammatory cytokines, and membrane associated Na+/K + ATPase and Ca2+ATPase and caspase-3 activity, collagen content, fibronectin protein levels were evaluated in various study groups. Histological studies were also carried out to analyze the cardiomyocyte damage, hypertrophy, fibrosis, and necrosis, while α-SMA, TGF-ß expression was checked by immunostaining. ISO administration enhanced ß-catenin gene expression and transcription which promoted oxidative and nitrosative stress, inflammatory cytokine release, reduced ATP levels, induced over-expression of fibrotic proteins resulting in cardiac hypertrophy, myocardial necrosis, functional and histological changes. However, antagonism of Wnt/ß-catenin pathway attenuated these ISO induced pathological manifestations. Notably, the co-treatment with ATP-sensitive K+ channel inhibitor partially, reduced the cardioprotective effects of Wnt/ß-catenin blocker pyrvinium in ISO rats. Thus Wnt/ß-catenin inhibition exhibits cardioprotective in ISO model by anti-oxidant, anti-inflammatory, anti-fibrotic properties and by possible involvement of ATP-sensitive potassium channel activation.

Metabolism disorder promotes isoproterenol-induced myocardial injury in mice with high temperature and high humidity and high-fat diet.

BACKGROUND: Isoproterenol (ISO), a synthetic on selective ß-adrenergic agonist, provides a simple and non-invasive method for inducing myocardial injury with lower mortality and higher reproducibility. Phlegm-damp syndrome, as known as "Tanshi" in Chinese, is one of Traditional Chinese Medicine (TCM) syndrome differentiation, which plays an important role in the development of cardiovascular diseases. However, the underlying mechanism remains unknown. METHODS: In our present study, a myocardial injury mouse model was introduced by ISO administration combined with high temperature and high humidity and high-fat diet to simulate phlegm-damp syndrome. Nontargeted metabolomics with LC-MS/MS was adopted to reveal serum metabolism profile for elucidating the possible molecular mechanism. RESULTS: The results of our study showed that phlegm-damp syndrome promoted ISO-induced myocardial injury by aggravating left ventricular hypertrophy and fibrosis, and increasing cardiac index. Our study also confirmed the presence of specific metabolites and disturbed metabolic pathways by comparing ISO mice and Tanshi mice, mainly including glycerophospholipid metabolism, arginine-proline metabolism, and sphingolipid signaling pathway. The lysoPCs, PCs, SMs, Sphingosine, and L-Arginine were the main metabolites that showed a difference between ISO and Tanshi mice, which might be the result of the underlying mechanism in the promotion of ISO-induced myocardial injury in mice with high temperature and high humidity and high-fat diet. CONCLUSION: Our current study provides new insights into contribution of metabolism disorder in promotion of ISO-induced myocardial injury in mice with high temperature and high humidity and high-fat diet, and new targets for clinical diagnosis and pharmacologic treatment of cardiovascular disease with phlegm-damp syndrome.

Artocarpus Altilis (Breadfruit) could Reverse Myocardial Infarction Through the Normalization of the Oxygen Haemoglobin Dissociation Curve.

OBJECTIVE: The study was performed to assess if hematological mechanisms such as blood flow modulation, P50 and Oxygen haemoglobin dissociation are involved in Artocarpus altilis leaf extract amelioration of Isoproterenol-Induced Myocardial Damage in rats. METHODS: Twenty (20) adult male Sprague-Dawley rats were randomly divided into 5 groups. Group 1 served as the control, group 3 and 5 received 50 and 100 mg/kg Artocarpus altilis water extract, respectively, after being induced with Isoproterenol twice (85 mg/ kg) at a 24-hour period. Group 2 received 85mg/kg isoproterenol only, while group 4 received 50 mg/kg Artocarpus altilis extract only for 6 days. The Hematological parameters were assessed using an automatic Coulter Counter, blood flow was assessed with the CODA machine using the tail cuff method, while blood viscosity was measured at native hematocrit and the oxygen haemoglobin dissociation curves were assessed with the BioProfiler and Hemox Analyzer at the end of seven days. RESULTS: Artocarpus altilis treatment ameliorated the ISO induced increases in viscosity, increased the ISO induced decreased blood flow and influenced oxygen release through its effects on the P50 of the oxygen hemoglobin dissociation curve, AA treatment also reversed the ISO induced weight loss. Apart from the changes in MCH, MCV, there were no significant differences in hematological parameters. CONCLUSION: This study reported the effects of Artocarpus atilis on the improvement of oxygen availability, the reduction of blood viscosity, and the improvement of blood flow through its influence on endothelial functions and NO availability. Our study further highlights The usefulness of A.atilis, as having a beneficial cardiovascular and haematological outcome in experimental myocardial infarction and as such, potential drug discovery for diseases of cardiovascular & hematological involvement.

Investigating the Mechanism of Shengmaiyin (Codonopsis pilosula) in the Treatment of Heart Failure Based on Network Pharmacology.

BACKGROUND AND OBJECTIVE: To explore the molecular mechanism by which Shengmaiyin (Codonopsis pilosula) (SMY) improves isoproterenol (ISO)-induced heart failure (HF) in rats via a traditional Chinese medicine (TCM) integrated pharmacology research platform, The Chinese Medicine Integrated Pharmacology Platform (TCMIP V2.0). METHOD: The chemical constituents and drug targets of SMY medicines were identified through TCMIP, and HF disease target information was collected. A prescription Chinese medicinecomponent- core target network was constructed through the TCM network mining module, and biological process and pathway enrichment analyses of core targets were conducted. In vivo experiments in rats were performed to verify the pathway targets. Hematoxylin and eosin staining was used to observe myocardial tissue morphology. ELISA kits were used to detect cAMP content, and Western blotting was used to detect the expression levels of signaling pathway-related proteins. RESULTS: The TCMIP analysis indicated that SMY treatment of HF activates the GS-ß-adrenergic receptor (ßAR)-cAMP-protein kinase A (PKA) signaling pathway. The in vivo experimental results confirmed this finding. High-dose SMY significantly improved the morphology of ISO-injured myocardium. The levels of G-protein-coupled receptor (GPCR), adenylate cyclase (AC), ßAR, and PKA proteins in myocardial tissue were significantly increased in the SMY group. In addition, the content of cAMP in myocardial tissue was increased, and the content of cAMP in serum was decreased. CONCLUSION: Based on the analysis of TCMIP, SMY treatment of HF may activate the GS-ßARcAMP- PKA signaling pathway. The findings provide a theoretical basis for further research on the anti-HF mechanism of SMY.

Bacopa monniera extract mitigates isoproterenol-induced cardiac stress via Nrf2/Keap1/NQO1 mediated pathway.

The present study was aimed to investigate the effect of standardised hydroalcoholic extract of Bacopa monniera (BME) against isoproterenol (ISO) induced cardiac stress. Isoproterenol (85 mg/kg body weight) was administered intraperitoneally to induce cardiac stress in rats. Bacopa monniera extract (BME75 and 150 mg/kg) was orally administered for 21 days followed by ISO on 22nd and 23rd experimental days. ISO caused significant cardiac damage, which was concomitant with increased apoptosis and attenuated expressions of Nrf2, HO-1, and regulating apoptotic protein expressions of Bax, Bcl2 and NOS2. Treatment with BME in rats significantly improved cardiac dysfunction by maintaining cardiac rhythm, myocardial integrity. Decreased oxidative stress by restored expressions of Nrf2, NQO1 and HO-1 followed by elevating antioxidant enzymes and total glutathione levels. Our present results suggest that the BME treatment strengthening the endogenous defence system through Nrf2 modulation and played a key role against cardiac oxidative stress induced by ISO in rats.

Evaluation of the cardioprotective effect of Casuarina suberosa extract in rats.

The aim of the current study was to examine and compare the cardioprotective activities of the chloroform and petroleum extracts the leaves of Casuarina suberosa in isoproterenol (ISO)-induced cardiac tissue oxidative stress. Rats were categorized into 6 groups as follows: control group, vehicle or Tween 80-treated group, ISO-treated group, chloroform extract + ISO treated group, petroleum ether extract + ISO treated group and Reference drug (Captopril) + ISO treated group. ISO injection significantly (p < 0.05) increased the activities of cardiac marker enzymes (CK-MB, LDH, ALT, and AST), cardiac troponin-I, levels of lipid peroxides (MDA), nitric oxide (NO), and vascular endothelial growth factor (VEGF), serum angiotensin-converting enzyme (ACE) activity and neutrophil infiltration marker; myeloperoxidase (MPO) in the cardiac tissues. Pretreatment with chloroform or petroleum ether extracts significantly (p < 0.05) prevented the ISO-induced alteration; they upregulated VEGF expression. Histopathological findings corroborated biochemical results. These extracts exerted a cardioprotective effect by alleviating oxidative stress.