Correlation between Metabolic Parameters and Warfarin Dose in Patients with Heart Valve Replacement of Different Genotypes.

Background: Warfarin has become the first choice for anticoagulation in patients who need lifelong anticoagulation due to its clinical efficacy and low price. However, the anticoagulant effect of warfarin is affected by many drugs, foods, etc. accompanied by a high risk of bleeding and embolism. The Vitamin K epoxide reductase complex 1 (VKORC1) and Cytochrome P450 2C9 (CYP2C9) genotypic variation can influence the therapeutic dose of warfarin. However, it is not clear whether there is a correlation between warfarin dose and liver function, kidney function and metabolic markers such as uric acid (UA) in patients with different genotypes. We performed a single-center retrospective cohort study to evaluate the factors affecting warfarin dose and to establish a dose conversion model for warfarin patients undergoing heart valve replacement. Methods: We studied 343 patients with a mechanical heart valve replacement, compared the doses of warfarin in patients with different warfarin-related genotypes (CYP2C9 and VKORC1), and analyzed the correlation between liver function, kidney function, UA and other metabolic markers and warfarin dose in patients with different genotypes following heart valve replacement. Results: Genotype analysis showed that 72.01% of patients had CYP2C9*1/*1 and VKORC1 mutant AA genotypes. Univariate regression analysis revealed that the warfarin maintenance dose was significantly correlated with gender, age, body surface area (BSA), UA and genotype. There was no correlation with liver or kidney function. Multiple linear regression analysis showed that BSA, genotype and UA were the independent factors influencing warfarin dose. Conclusions: There is a significant correlation between UA content and warfarin dose in patients with heart valve replacement genotypes CYP2C9*1/*1/VKORC1(GA+GG), CYP2C9*1/*1/VKORC1AA and CYP2C9*1/*1/VKORC1AA.

GPR30 Alleviates Pressure Overload-Induced Myocardial Hypertrophy in Ovariectomized Mice by Regulating Autophagy.

The incidence of heart failure mainly resulting from cardiac hypertrophy and fibrosis increases sharply in post-menopausal women compared with men at the same age, which indicates a cardioprotective role of estrogen. Previous studies in our group have shown that the novel estrogen receptor G Protein Coupled Receptor 30 (GPR30) could attenuate myocardial fibrosis caused by ischemic heart disease. However, the role of GPR30 in myocardial hypertrophy in ovariectomized mice has not been investigated yet. In this study, female mice with bilateral ovariectomy or sham surgery underwent transverse aortic constriction (TAC) surgery. After 8 weeks, mice in the OVX + TAC group exhibited more severe myocardial hypertrophy and fibrosis than mice in the TAC group. G1, the specific agonist of GPR30, could attenuate myocardial hypertrophy and fibrosis of mice in the OVX + TAC group. Furthermore, the expression of LC3II was significantly higher in the OVX + TAC group than in the OVX + TAC + G1 group, which indicates that autophagy might play an important role in this process. An in vitro study showed that G1 alleviated AngiotensionII (AngII)-induced hypertrophy and reduced the autophagy level of H9c2 cells, as revealed by LC3II expression and tandem mRFP-GFP-LC3 fluorescence analysis. Additionally, Western blot results showed that the AKT/mTOR pathway was inhibited in the AngII group, whereas it was restored in the AngII + G1 group. To further verify the mechanism, PI3K inhibitor LY294002 or autophagy activator rapamycin was added in the AngII + G1 group, and the antihypertrophy effect of G1 on H9c2 cells was blocked by LY294002 or rapamycin. In summary, our results demonstrate that G1 can attenuate cardiac hypertrophy and fibrosis and improve the cardiac function of mice in the OVX + TAC group through AKT/mTOR mediated inhibition of autophagy. Thus, this study demonstrates a potential option for the drug treatment of pressure overload-induced cardiac hypertrophy in postmenopausal women.

Warfarin-Induced Calcification: Potential Prevention and Treatment Strategies.

Warfarin is clinically used as the first choice for long-term anticoagulant therapy, and for the prevention of thromboembolic events. However, when used at low doses in the long term or high doses in the short term, warfarin treatment may result in tissue calcifications-such as calcifications in the coronary arteries, peripheral vascular system, blood vessels of patients with atrial fibrillation and chronic kidney disease, and vascular valves-and atherosclerotic plaque calcification. These warfarin-induced calcifications may affect cardiovascular function and exacerbate diseases such as diabetes and hypertension. Studies have shown that quercetin, osteoprotegerin, sclerosin, and sodium thiosulfate may alleviate these effects by interfering in the Wnt/ ß -catenin, TG2/ ß -catenin, Bone Morphogenetic Protein 2 (BMP2), and Eicosapentaenoic Acid/Matrix Metallopeptidase-9 (EPA/MMP-9) pathways, respectively. Nevertheless, the mechanism underlying warfarin-induced calcification remains unknown. Therefore, the question as to how to effectively attenuate the calcification induced by warfarin and ensure its anticoagulant effect remains an urgent clinical problem that needs to be resolved. To utilize warfarin rationally and to effectively attenuate the calcifications, we focused on the clinical phenomena, molecular mechanisms, and potential strategies to prevent calcification. Highlighting these aspects could provide new insights into the effective utilization of warfarin and the reduction of its associated calcification effects.

Beclin1 Haploinsufficiency accentuates second-hand smoke exposure -induced myocardial Remodeling and contractile dysfunction through a STING-mediated mechanism.

Second-hand smoking evokes inflammation and cardiovascular diseases. Recent evidence has revealed a pivotal role for deranged autophagy in smoke exposure-induced cardiac anomalies. This study evaluated the impact of haploinsufficiency of the mTOR-independent autophagy protein Beclin1 on side-stream smoke exposure-induced cardiac anomalies and mechanism(s) involved. Adult WT and Beclin1 haploinsufficiency (Becn+/-) mice were exposed to cigarette smoke for 1 h daily for 90 days. Echocardiographic, cardiomyocyte function, intracellular Ca2+, autophagy, mitophagy, apoptosis and inflammation were examined. DHE staining was employed to evaluate O2- level. Our data revealed that Beclin1 deficiency exacerbated smoke exposure-induced myocardial anomalies in geometry, fractional shortening, cardiomyocyte function, intracellular Ca2+ handling, TEM ultrastructure, and inflammation along with pronounced apoptosis and O2- production. Side-stream smoke provoked excessive autophagy/mitophagy, mtDNA release, and activation of innate immune response signals cyclic GMP-AMP synthase (cGAS) and its effector - stimulator of interferon genes (STING), the effect was abolished or unaffected by Becn haploinsufficiency. STING phosphorylation was overtly promoted by smoke exposure in Becn+/- mice. Smoke exposure also suppressed phosphorylation of mTOR although it facilitated that of ULK1 in both groups. In vitro data revealed that inhibition of cGAS or STING failed to affect smoke extract-induced mitophagy although they abrogated smoke extract-induced cardiomyocyte dysfunction except cGAS inhibition in Becn+/- mice. These data suggest that Beclin1 is integral in the maintenance of cardiac homeostasis under side-stream smoke exposure via a STING-mediated mechanism.

Cardiac-specific overexpression of metallothionein attenuates L-NAME-induced myocardial contractile anomalies and apoptosis.

Hypertension contributes to the high cardiac morbidity and mortality. Although oxidative stress plays an essential role in hypertensive heart diseases, the mechanism remains elusive. Transgenic mice with cardiac overexpression of metallothionein, a heavy metal-binding scavenger, were challenged with NG -nitro-L-arginine methyl ester (L-NAME) for 14 days prior to measurement of myocardial contractile and intracellular Ca2+ anomalies as well as cell signalling mechanisms using Western blot and immunofluorescence analysis. L-NAME challenge elicited hypertension, macrophage infiltration, oxidative stress, inflammation and cardiac dysfunction manifested as increased proinflammatory macrophage marker F4/80, interleukin-1ß (IL-1ß), intracellular O2- production, LV end systolic and diastolic diameters as well as depressed fractional shortening. L-NAME treatment reduced mitochondrial membrane potential (MMP), impaired cardiomyocyte contractile and intracellular Ca2+ properties as evidenced by suppressed peak shortening, maximal velocity of shortening/relengthening, rise in intracellular Ca2+ , along with elevated baseline and peak intracellular Ca2+ . These unfavourable mechanical changes and decreased MMP (except blood pressure and macrophage infiltration) were alleviated by overexpression of metallothionein. Furthermore, the apoptosis markers including BAD, Bax, Caspase 9, Caspase 12 and cleaved Caspase 3 were up-regulated while the anti-apoptotic marker Bcl-2 was decreased by L-NAME treatment. Metallothionein transgene reversed L-NAME-induced changes in Bax, Bcl-2, BAD phosphorylation, Caspase 9, Caspase 12 and cleaved Caspase 3. Our results suggest that metallothionein protects against L-NAME-induced myocardial contractile anomalies in part through inhibition of apoptosis.

Quercetin improve ischemia/reperfusion-induced cardiomyocyte apoptosis in vitro and in vivo study via SIRT1/PGC-1α signaling.

AIM: To evaluate the effects of quercetin to improve ischemia/reperfusion-induced cardiomyocyte apoptosis in vitro and in vivo study. METHODS: The cells were divided into five groups: model control (MC) group was ischemia/reperfusion (I/R) model group; DL group was treated with 25 mL/L quercetin based on MC group; DM group was treated with 50 ml/L quercetin based on MC group; DH group was treated with 100 mL/L quercetin based on MC group; Meto group was treated with metoprolol based on MC group. In the in vivo study, the rats were divided into five groups: MC group was I/R model group; DL group was treated with 25 mg/kg quercetin; DM group was treated with 50 mg/kg quercetin; DM group was treated with 100 mg/kg quercetin; Meto group was treated with Meto as positive drug. RESULTS: The cell apoptosis rates of quercetin treated groups (DL, DM, and DH groups) were significantly suppressed compared with the MC group. The silent information regulatory factor 1 (SIRT1), peroxisome proliferators-activated receptor-γ coactivator-1α (PGC-1α), and Bcl-2 proteins expression of quercetin treated were significantly upregulation compared with MC group (P < 0.05, respectively), and Bax protein expression of quercetin treated group was significantly downregulation compared with MC group ( P < 0.05, respectively). In the vivo study, the myocardial pathological morphology of quercetin treated groups was improved. The cell apoptosis number of quercetin treated group were significantly suppressed compared with MC group by terminal deoxynucleotidyl transferase dUTP nick end labeling assay ( P < 0.05, respectively). SIRT1, PGC-1a, Bcl-2, and Bax proteins expressions of quercetin treated groups were significant differences compared with MC group in myocardial tissue ( P < 0.05, respectively). CONCLUSION: Quercetin had improved the myocardial ischemia/reperfusion-induced cardiomyocyte apoptosis via SIRT1/PGC-1α signaling.

Rutin attenuates doxorubicin-induced cardiotoxicity via regulating autophagy and apoptosis.

Doxorubicin as anticancer agent can cause dose-dependent cardiotoxicity and heart failure in the long term. Rutin as a polyphenolic flavonoid has been illustrated to protect hearts from diverse cardiovascular diseases. Its function is known to be related to its antioxidant and antiinflammatory activity which may regulate multiple cellular signal pathways. However, the role of rutin on doxorubicin-induced cardiotoxicity has yet to be discovered. In this study, we explored the protective role of rutin on doxorubicin-induced heart failure and elucidated the potential mechanisms of protective effects of rutin against cardiomyocyte death. We analyzed cardiac tissues at the time point of 8weeks after doxorubicin treatment. The results by echocardiography, TUNEL staining, Masson's trichrome staining as well as Western blot analysis revealed that doxorubicin induced remarkable cardiac dysfunction and cardiotoxicity in mice hearts and cardiomyocytes, which were alleviated by rutin treatment. Western blot analysis indicated that the underlying mechanisms included inhibition excessive autophagy and apoptosis mediated by Akt activation. Collectively, our findings suggest that suppression of autophagy and apoptosis by administration of rutin could attenuate doxorubicin-induced cardiotoxicity, which enhances our knowledge to explore new drugs and strategies for combating this devastating side effect induced by doxorubicin. This article is part of a Special Issue entitled: Genetic and epigenetic control of heart failure - edited by Jun Ren & Megan Yingmei Zhang.

Naringenin ameliorates hypoxia/reoxygenation-induced endoplasmic reticulum stress-mediated apoptosis in H9c2 myocardial cells: involvement in ATF6, IRE1α and PERK signaling activation.

Naringenin, a flavanone mainly derived from grapes and citrus fruits, has been reported to exhibit cardioprotective effects. Accumulating evidence has confirmed that endoplasmic reticulum (ER) stress-mediated apoptosis participates in the process of myocardial ischemia/reperfusion injury and inhibiting ER stress is a potential therapeutic target/strategy in preventing cardiovascular diseases. Herein, the current study was designed to investigate whether naringenin protects H9c2 myocardial cells against hypoxia/reoxygenation (H/R) injury via attenuating ER stress or ER stress-mediated apoptosis. Our results showed that naringenin treatment resulted in obvious increases in the viability of H9c2 cells and the expression of Bcl-2 (anti-apoptotic protein), and decreases in the morphological changes of apoptotic cells, the activity of caspase-3 and the expression of Bax (pro-apoptotic protein) in H/R-treated H9c2 cells, implying the protective effects of naringenin against H/R-induced injury. In addition, naringenin also significantly reversed H/R-induced ER stress as evidenced by the up-regulation of Glucose-regulated protein 78, C/EBP homologous protein and Cleaved caspase-12 proteins. Meanwhile, naringenin remarkably reversed H/R-induced the increases in the expression of cleaved activating transcription factor 6 (ATF6) and phosphorylation levels of phospho-extracellular regulated protein kinases (PERK) and inositol-requiring enzyme-1α (IRE1α) in H9c2 cells. Finally, we found that ATF6 siRNA, PERK siRNA or IRE1α siRNA abolished H/R-induced cytotoxicity and apoptosis in H9c2 cells. In conclusion, these results confirmed that ER stress-mediated apoptosis contributes to the protection effects of naringenin against H/R injury, which is potentially involved in ATF6, IRE1α and PERK signaling activation.

Investigating the protective effects of Astragalus polysaccharides on cyclophosphamide-induced bone marrow suppression in mice and bone mesenchymal stem cells.

BACKGROUND: This study determines the role and mechanism of APS in cyclophosphamide-induced myelosuppression in mice and bone mesenchymal stem cells (BMSCs) cell model. METHODS: Cy-induced myelosuppression mice and BMSCs cell model were established. Fifty C57BL/6 mice (weighing 20 ± 2 g) were randomly divided into five groups. Femur and tibia samples, bone marrow samples, and blood samples were collected 3 days after the last injection of Cy. Histopathology changes and cell apoptosis were detected. Cell viability, apoptosis, cycle distribution, reactive oxygen species activity, osteogenesis ability, and protein levels were detected. γ-H2AX and senescence-associated ß-galactosidase activity expression was detected by immunofluorescence. Cy-induced senescence and Wnt/ß-catenin related protein levels were detected using western blotting. RESULTS: The results showed that APS effectively induced Cy-induced histological injury and cell apoptosis rate. After treated with APS, ROS and ALP levels were significantly increased. In BMSCs, cell viability, apoptosis, and cell cycle distribution were also influenced by APS treatment. Compared with the control group, cell viability was significantly increased, the cell apoptosis rate was decreased while the number of cells remained in the G0-G1 phase was increased. Meanwhile, ROS levels were significantly increased in APS group. Cell senescence and Wnt/ß-catenin related protein (γ-H2AX, SA-ß-gal, p21, p16, p-ß-catenin/ ß-catenin, c-Myc, and AXIN2) levels were also altered both in vivo and in vitro. Interestingly, the effects of APS were reversed by BML-284. CONCLUSION: Our results indicate that APS protected Cy-induced myelosuppression through the Wnt/ß-catenin pathway and APS is a potential therapeutic drug for Cy-induced myelosuppression.

Application of radioactive iodine-125 microparticles in hepatocellular carcinoma with portal vein embolus.

BACKGROUND: Radioactive iodine-125 (125I) microparticle therapy is a new type of internal radiation therapy that has shown unique advantages in the treatment of malignant tumors, especially hepatocellular carcinoma. Patients with hepatocellular carcinoma frequently experience portal vein embolism, which exacerbates the difficulty and complexity of treatment. 125I particles, used in local radiotherapy, can directly act on tumor tissue and reduce damage to surrounding healthy tissue. Through retrospective analysis, this study discussed the efficacy and safety of radioactive 125I particles in portal vein embolization patients with hepatocellular carcinoma in order to provide more powerful evidence supporting clinical treatment. AIM: To investigate the effect of transcatheter arterial chemoembolization combined with portal vein 125I particle implantation in the treatment of primary liver cancer patients with portal vein tumor thrombus and its influence on liver function. METHODS: The clinical data of 96 patients with primary liver cancer combined with portal vein tumor thrombus admitted to our hospital between January 2020 and December 2023 were retrospectively analyzed. Fifty-two patients received treatment with transcatheter arterial chemoembolization and implantation of 125I particles in the portal vein (combination group), while 44 patients received treatment with transcatheter arterial chemoembolization alone (control group). The therapeutic effects on tumor lesions, primary liver cancer, and portal vein tumor embolisms were compared between the two groups. Changes in relevant laboratory indexes before and after treatment were evaluated. The t test was used to compare the measurement data between the two groups, and the χ 2 test was used to compare the counting data between groups. RESULTS: The tumor lesion response rate in the combination group (59.62% vs 38.64%) and the response rate of patients with primary liver cancer complicated with portal vein tumor thrombus (80.77% vs 59.09%) were significantly greater than those in the control group (χ 2 = 4.196, 5.421; P = 0.041, 0.020). At 8 wk after surgery, the serum alpha-fetoprotein, portal vein main diameter, and platelet of the combined group were significantly lower than those of the control group, and the serum alanine aminotransferase, aspartate aminotransferase, and total bilirubin were significantly greater than those of the control group (t = 3.891, 3.291, 2.330, 3.729, 3.582, 4.126; P < 0.05). The serum aspartate aminotransferase, alanine aminotransferase, and total bilirubin levels of the two groups were significantly greater than those of the same group 8 wk after surgery (P < 0.05), and the peripheral blood platelet, alpha-fetoprotein, and main portal vein diameter were significantly less than those of the same group before surgery (P < 0.05). CONCLUSION: In patients with primary liver cancer and a thrombus in the portal vein, transcatheter arterial chemoembolization plus portal vein 125I implantation is more effective than transcatheter arterial chemoembolization alone. However, during treatment it is crucial to pay attention to liver function injury caused by transcatheter arterial chemoembolization.

All-printed organic photodetectors with metal electrodes enabled by one-step solvent-mediated transfer printing technology.

A one-step solvent-mediated transfer printing technology (sTPT) is proposed to fabricate printable silver (Ag) electrodes. This simple approach can realize the residuals in the active layer serving as the mediator due to the capillary action without the use of any additional solvent. The as-cast polydimethylsiloxane (PDMS) was used as the stamp in the fabrication process. The residual solvent and the as-cast PDMS stamps simplified the fabrication process, while the transfer-printed Ag electrodes presented favorable conductivity and improved hydrophobicity due to the presence of residual PDMS on the surface of Ag, indicating the superiority as the top electrode for organic photodetectors (OPDs). Compared to the devices with the top Ag electrodes fabricated by the conventional evaporation method, we demonstrated that the OPDs with transfer-printed Ag electrodes presented better performance than that of the reference devices, including suppressed dark current, enlarged linear dynamic range, shortened response time, and optimized durability. These improved performances can be attributed to the fewer traps at the interface between the active layer and Ag electrodes. The sTPT may be a promising method for the fabrication of OPDs owing to the simplified fabrication process and enhanced device performance.

GPR30 Agonist G1 Mitigates Sepsis-Induced Cardiac Dysfunction by Inhibiting ACE2/c-FOS-Mediated Necroptosis in Female Mice.

Sepsis is a severe inflammatory syndrome with high mortality and morbidity. Sepsis-induced myocardial dysfunction (SIMD) is a common cause of death in sepsis. The female sex is less susceptible to sepsis-related organ dysfunction, although the underlying mechanism of this sex difference remains unclear. This study explored the role of estrogen receptor G protein-coupled estrogen receptor 30 (GPR30) in septic cardiac dysfunction. Results from the present study indicated that GPR30 activation by the G1 agonist protected female mouse hearts against SIMD exposed to lipopolysaccharides. However, this beneficial effect was absent in female ACE2-knockout mice, as demonstrated by poorer cardiac contractility, myocardial injury, and necroptosis. We also demonstrated that the Stat6 transcription factor induced ace2 transcription by enhancing its promoter activity under GPR30 activation in septic hearts. The adenovirus-mediated inhibition of ACE2 targeting c-FOS expression reversed the deterioration, restored cardiac function, and improved survival in female ACE2-knockout mice. These results demonstrate the essential role of GPR30/STAT6/ACE2/c-FOS-mediated necroptosis in G1-mediated protection and provide novel insight into the pathogenesis of sepsis-related organ damage.

Irisin improves diabetic cardiomyopathy-induced cardiac remodeling by regulating GSDMD-mediated pyroptosis through MITOL/STING signaling.

Diabetic cardiomyopathy (DCM) is a common complication of diabetes mellitus (DM). However, the mechanisms underlying DCM-induced cardiac injury remain unclear. Recently, the role of cyclic GMP-AMP synthase/stimulator of interferon gene (cGAS/STING) signaling and pyroptosis in DCM has been investigated. Based on our previous results, this study was designed to examine the impact of irisin, mitochondrial ubiquitin ligase (MITOL/MARCH5), and cGAS/STING signaling in DCM-induced cardiac dysfunction and the effect of gasdermin D (GSDMD)-dependent pyroptosis. High-fat diet-induced mice and H9c2 cells were used for cardiac geometry and function or pyroptosis-related biomarker assessment at the end of the experiments. Here, we show that DCM impairs cardiac function by increasing cardiac fibrosis and GSDMD-dependent pyroptosis, including the activation of MITOL and cGAS/STING signaling. Our results confirmed that the protective role of irisin and MITOL was partially offset by the activation of cGAS/STING signaling. We also demonstrated that GSDMD-dependent pyroptosis plays a pivotal role in the pathological process of DCM pathogenesis. Our results indicate that irisin treatment protects against DCM injury, mitochondrial homeostasis, and pyroptosis through MITOL upregulation.

The value of lymphocyte to monocyte ratio in the prognosis of head and neck squamous cell carcinoma: a meta-analysis.

Objectives: Although lymphocyte-monocyte ratio (LMR) is a potential prognostic biomarker in many tumor indications, a doubt occurs around its association with head and neck squamous cell carcinoma (HNSCC). We aimed to evaluate the predictive value of LMR in patients with HNSCC. Methods: We searched PubMed, Web of Science, EMBASE, and the Cochrane database from inception to May 8, 2023 for systematic review and meta-analysis on LMR and outcomes related to HNSCC development. STATA software was used to estimate the correlation between LMR and prognosis. The risk ratio (hazard ratio, HR) and 95% confidence interval l (CI) for overall survival (OS), disease-free survival (DFS), cancer-specific survival (CSS), and progression-free survival (PFS) were calculated, and the association between LMR and OS was further validated by subgroup analysis. The source of heterogeneity with the results of subgroup analysis was analyzed by meta-regression analysis. This meta-analysis was registered at PROSPERO (CRD42023418766). Results: After a comprehensive exploration, the results of 16 selected articles containing 5,234 subjects were evaluated. A raised LMR was connected to improved OS (HR = 1.36% CI [1.14-1.62] P = 0.018), DFS (HR = 0.942, 95% CI [0.631-1.382], P = 0.02), and PFS (HR = 0.932, 95% CI [0.527-1.589], P < 0.022). Subgroup analysis indicated that patients with a low LMR level had a poor prognosis with a critical value of ≥4. The LMR was found to be prognostic for cases with an LMR of <4. The meta-regression analysis showed that the cut-off values and treatment methods were the primary sources of high heterogeneity in patients with HNSCC. Conclusions: Our study suggested that an elevated LMR is a potential prognostic biomarker in patients with HNSCC and could be used to predict patient outcomes.

Improvement of Cardiovascular Function in Aging Females by the Prolonged Activation of G Protein-Coupled Estrogen Receptor.

Ample evidence suggests that estrogen replacement therapy is associated with beneficial effects with regard to cardiovascular diseases when the therapy is initiated temporally close to menopause but not when it is initiated later. Little is known about the complex interactions between hormone receptors after menopause. Coronary artery function and cardiac function were measured in rats that had either received no treatment or had been pretreated with an androgen receptor (AR) antagonist and/or a GPER agonist G-1. ICI 182,780 was used to block the classical estrogen receptors (ERs) to investigate their complex interactions with GPER. The beneficial effects of GPER were only observed by blocking ARs and classical ERs in aged female rats. The results demonstrate that GPER activation is a potential therapeutic target for the inhibition of age-dependent coronary artery dysfunction and cardiac dysfunction under the condition of blocking ARs and classical ERs after menopause. CLINICAL RELEVANCE: The risk of cardiovascular disease in postmenopausal women significantly increased. The role of sex hormones and their receptors during this process is still complicated. Our present study demonstrated that the imbalance of androgen and estrogen may contribute to the impairment of vascular reactivity and subsequent cardiac function. Treatment with GPER agonist G1 combined with the inhibition of ERα and ERß could improve vascular function and reduce the myocardial ischemia reperfusion injury. These findings may provide the novel and effective strategy for the treatment of cardiovascular diseases in postmenopausal women.

The Role of G Protein-Coupled Estrogen Receptor (GPER) in Vascular Pathology and Physiology.

OBJECTIVE: Estrogen is indispensable in health and disease and mainly functions through its receptors. The protection of the cardiovascular system by estrogen and its receptors has been recognized for decades. Numerous studies with a focus on estrogen and its receptor system have been conducted to elucidate the underlying mechanism. Although nuclear estrogen receptors, including estrogen receptor-α and estrogen receptor-ß, have been shown to be classical receptors that mediate genomic effects, studies now show that GPER mainly mediates rapid signaling events as well as transcriptional regulation via binding to estrogen as a membrane receptor. With the discovery of selective synthetic ligands for GPER and the utilization of GPER knockout mice, significant progress has been made in understanding the function of GPER. In this review, the tissue and cellular localizations, endogenous and exogenous ligands, and signaling pathways of GPER are systematically summarized in diverse physiological and diseased conditions. This article further emphasizes the role of GPER in vascular pathology and physiology, focusing on the latest research progress and evidence of GPER as a promising therapeutic target in hypertension, pulmonary hypertension, and atherosclerosis. Thus, selective regulation of GPER by its agonists and antagonists have the potential to be used in clinical practice for treating such diseases.

Melatonin Restores Autophagic Flux by Activating the Sirt3/TFEB Signaling Pathway to Attenuate Doxorubicin-Induced Cardiomyopathy.

Doxorubicin (DOX) chemotherapy in cancer patients increases the risk of the occurrence of cardiac dysfunction and even results in congestive heart failure. Despite the great progress of pathology in DOX-induced cardiomyopathy, the underlying molecular mechanisms remain elusive. Here, we investigate the protective effects and the underlying mechanisms of melatonin in DOX-induced cardiomyopathy. Our results clearly show that oral administration of melatonin prevented the deterioration of cardiac function caused by DOX treatment, which was evaluated by left ventricular ejection fraction and fractional shortening as well as cardiac fibrosis. The ejection fraction and fractional shortening in the DOX group were 49.48% and 25.5%, respectively, while melatonin treatment increased the ejection fraction and fractional shortening to 60.33 and 31.39 in wild-type mice. Cardiac fibrosis in the DOX group was 3.97%, while melatonin reduced cardiac fibrosis to 1.95% in wild-type mice. Sirt3 is a mitochondrial deacetylase and shows protective effects in diverse cardiovascular diseases. Therefore, to test whether Sirt3 is a key factor in protection, Sirt3 knockout mice were used, and it was found that the protective effects of melatonin in DOX-induced cardiomyopathy were partly abolished. Further analysis revealed that Sirt3 and its downstream molecule TFEB were downregulated in response to DOX treatment, while melatonin administration was able to significantly enhance the expressions of Sirt3 and TFEB. Our in vitro study demonstrated that melatonin enhanced lysosomal function by increasing the Sirt3-mediated increase at the TFEB level, and the accumulation of autolysosomes induced by DOX treatment was attenuated. Thus, autophagic flux disrupted by DOX treatment was restored by melatonin supplementation. In summary, our results demonstrate that melatonin protects the heart against DOX injury by the restoration of autophagic flux via the activation of the Sirt3/TFEB signaling pathway.

Mitochondrial aldehyde dehydrogenase rescues against diabetic cardiomyopathy through GSK3ß-mediated preservation of Mitochondrial integrity and parkin-mediated mitophagy.

Mitochondrial aldehyde dehydrogenase (ALDH2) offers proven cardiovascular benefit although its impact in diabetes remains elusive. This study examined the effect of ALDH2 overexpression (OE) and knockout (KO) on diabetic cardiomyopathy and mechanism involved with a focus on mitochondrial integrity. ALDH2 OE and KO mice were challenged with streptozotocin (STZ, 200 mg/kg. i.p.) to establish diabetes. Diabetic patients displayed reduced plasma ALDH2 activity, cardiac remodeling and diastolic dysfunction. STZ challenge prompted reduced respiratory exchange ratio (RER), dampened fractional shortening, ejection fraction, increased LV end systolic and diastolic diameters, cardiac remodeling, cardiomyocyte contractile and intracellular Ca2+ defects (depressed peak shortening and maximal velocity of shortening/relengthening, prolonged relengthening, dampened intracellular Ca2+ rise and clearance), myocardial ultrastructural injury, oxidative stress, apoptosis and mitochondrial damage, the effects of which were overtly attenuated and accentuated by ALDH2 OE and KO, respectively. Immunoblotting revealed downregulated mitochondrial proteins PPARγ coactivator 1α (PGC-1α) and UCP-2, Ca2+ regulatory proteins including SERCA and Na+-Ca2+ exchanger, elevated phospholamban, dampened autophagy and mitophagy (LC3B ratio, TOM20, Parkin, FUNDC1 and BNIP3), disrupted phosphorylation of Akt, GSK3ß and Foxo3a, and elevated PTEN phosphorylation, the effect of which was reversed and worsened by ALDH2 OE and KO, respectively (except FUNDC1 and BNIP3). In vivo and in vitro data revealed that novel ALDH2 activator torezolid/Alda-1 protected against STZ or high glucose-induced cardiac anomalies, the effect was nullified by inhibition of Akt, GSK3ß, Parkin and mitochondrial coupling. Our data discerned a vital role for ALDH2 in diabetic cardiomyopathy possibly through regulation of Akt, GSK3ß activation, parkin mitophagy and mitochondrial function.

Pentacyclic triterpene oleanolic acid protects against cardiac aging through regulation of mitophagy and mitochondrial integrity.

Advanced aging exhibits altered cardiac geometry and function involving mitochondrial anomaly. Natural compounds display promises in the regulation of cardiac homeostasis via governance of mitochondrial integrity in aging. This study examined the effect of oleanolic acid (OA), a natural pentacyclic triterpenoid with free radical scavenging and P450 cyclooxygenase-regulating properties, on cardiac aging and mechanisms involved with a focus on mitophagy. Young (4-5 month-old) and old (22-24 month-old) mice were treated with OA for 6 weeks prior to assessment of cardiac function, morphology, ultrastructure, mitochondrial integrity, cell death and autophagy. Our data revealed that OA treatment alleviated aging-induced changes in myocardial remodeling (increased heart weight, chamber size, cardiomyocyte area and interstitial fibrosis), contractile function and intracellular Ca2+ handling, apoptosis, necroptosis, inflammation, autophagy and mitophagy (LC3B, p62, TOM20 and FUNDC1 but not BNIP3 and Parkin). OA treatment rescued aging-induced anomalies in mitochondrial ultrastructure (loss of myofilament alignment, swollen mitochondria, increased circularity), mitochondrial biogenesis and O2- production without any notable effect at young age. Interestingly, OA-offered benefit against cardiomyocyte aging was nullified by deletion of the mitophagy receptor FUNDC1 using FUNDC1 knockout mice, denoting an obligatory role for FUNDC1 in OA-elicited preservation of mitophagy. OA reconciled aging-induced changes in E3 ligase MARCH5 but not FBXL2, and failed to affect aging-induced rises in IP3R3. Taken together, our data indicated a beneficial role for OA in attenuating cardiac remodeling and contractile dysfunction in aging through a FUNDC1-mediated mechanism.

Irisin attenuates sepsis-induced cardiac dysfunction by attenuating inflammation-induced pyroptosis through a mitochondrial ubiquitin ligase-dependent mechanism.

Sepsis-induced cardiac dysfunction is a leading cause of mortality in intensive care units. However, the molecular mechanisms underlying septic cardiomyopathy remain elusive. Irisin is a cleaved product of fibronectin type III domain-containing protein 5 (FNDC5) that protects the heart from ischemia/reperfusion injury through upregulation of mitochondrial ubiquitin ligase (MITOL). Gasdermin D (GSDMD)-dependent pyroptosis plays a pivotal role in septic cardiomyopathy by regulating mitochondrial homeostasis. However, whether irisin can regulate MITOL to inhibit GSDMD-dependent pyroptosis in septic cardiomyopathy is yet to be investigated. Thus, this study was designed to explore the role of irisin in septic cardiomyopathy and its underlying molecular mechanisms. Our results demonstrate that irisin improves cardiac function against sepsis-induced cardiac dysfunction by reducing cardiac inflammation and myocardial pyroptosis. Using MITOL siRNA in vitro, the results revealed that the protective role of irisin against lipopolysaccharide (LPS)-induced cell injury was mediated by MITOL activation and the resulting inhibition of GSDMD-dependent pyroptosis. Moreover, irisin alleviated LPS-induced H9c2 cell injury by suppressing IL-1ß expression and reducing serum LDH and CK-MB concentrations in a MITOL/GSDMD-dependent manner. Collectively, our data suggest that irisin treatment ameliorates cardiac dysfunction in septic cardiomyopathy by activating MITOL and inhibiting GSDMD-dependent pyroptosis. These findings highlight the clinical relevance and therapeutic potential of irisin and MITOL for the management of sepsis-induced cardiac dysfunction.