Titration of sedentary behavior with varying physical activity levels reduces mortality in patients with type 2 diabetes.

CONTEXT: Both physical activity (PA) and sedentary behavior (SB) exert important impact on type 2 diabetes, but it remains unclear how maximum impact on improving the mortality and optimized proportion of the two lifestyles combination exists. OBJECTIVE: To explore the impacts of PA/SB combinations on mortality in patients with diabetes. METHODS: Patients with type 2 diabetes patients samplings were collected from the National Health and Nutrition Examination Survey (NHANES) dataset. Their lifestyles were categorized into eight groups based on combinations of the PA and SB levels. Cox proportional hazards models were used to calculate hazard ratios and 95% confidence intervals. RESULTS: During the follow-up period, 1,148 deaths (18.94%) were recorded. High SB (sedentary time ≥6 hours/day) was significantly associated with higher all-cause mortality (HR 1.65). In participants with low SB (<6 hours/day), low PA was associated with lower all-cause mortality (HR 0.43), while further increase of PA level did not show further reduction in either all-cause or cardiovascular mortality. In contrast, in participants with high SB，all levels of PA were associated with lower all-cause mortality (p<0.05), but only moderate PA was associated with lower cardiovascular mortality (HR 0.30). CONCLUSIONS: In patients with type 2 diabetes, different combinations of various levels of PA and SB are associated with different degree of risk for all-cause or cardiovascular mortality.

CircMap4k2 reactivated by aneurysm plication alleviates residual cardiac remodeling after SVR by enhancing cardiomyocyte proliferation in post-MI mice.

INTRODUCTION: Surgical ventricular reconstruction (SVR) is an alternative therapeutic approach in patients with refractory heart failure (HF), but residual remodeling after SVR limits the improvement of HF. Recently, we reported that SVR may act as an environmental cue to reactivate endogenous proliferation of cardiomyocytes; however, it is unclear whether enhancing endogenous cardiomyocyte regeneration further improves HF after SVR. OBJECTIVES: We aimed to explore whether circular RNAs (circRNAs) would involved in SVR and their mechanisms. METHODS: Male C57BL/6 mice were subjected to myocardial infarction (MI) or sham surgery. Four weeks later, MI mice with a large ventricular aneurysm underwent SVR or a second open-chest operation only. Echocardiography and histological analysis were used to evaluate heart function, cardiac remodeling, and myocardial regeneration. Sequencing of circular RNAs, RNA immunoprecipitation, RNA pulldown, and luciferase reporter assay were used to explore the underlying mechanisms. RESULTS: SVR markedly attenuated cardiac remodeling and induced cardiomyocyte regeneration, as evidenced by positive staining of Ki-67, phospho-histone H3 (pH3), and Aurora B in the plication zone, but significant residual remodeling still existed in comparison with the sham group. Sequencing results showed that SVR altered the expression profile of cardiac circRNAs, and circMap4k2 was identified as the most upregulated one. After characterizing circMap4k2, we noted that overexpression of circMap4k2 significantly promoted proliferation of cardiomyocytes in cultured neonatal rat cardiomyocytes and silencing of circMap4k2 significantly inhibited it; similar results were obtained in SVR-treated MI mice but not in MI mice without SVR treatment. Residual cardiac remodeling after SVR was further attenuated by circMap4k2 overexpression. CircMap4k2 bound with miR-106a-3p and inhibited cardiomyocyte proliferation by targeting a downstream effector of the antizyme inhibitor 1 (Azin1) gene. CONCLUSIONS: CircMap4k2 acts as an environmental cue and targets the miR-106a-3p/Azin1 pathway to increase cardiac regeneration in the plication zone and attenuate residual remodeling after SVR.

Comparisons of procedural characteristics and clinical outcomes between SMARTTOUCH SURROUNDFLOW catheter and other catheters for atrial fibrillation radiofrequency catheter ablation: a systematic literature review.

BACKGROUND: SMARTTOUCH SURROUNDFLOW (STSF) catheter is the new generation of SMARTTOUCH (ST) catheter with an upgraded irrigation system for radiofrequency catheter ablation (RFCA) in patients with atrial fibrillation (AF). METHODS: This systematic literature review searched the major English and Chinese bibliographic databases from 2016 to 2022 for any original clinical studies assessing the STSF catheter for RFCA in AF patients. Meta-analysis with a random effects model was used for evidence synthesis. RESULTS: Pooled outcomes from 19 included studies indicated that STSF catheter was associated with a significantly shorter procedure time (weighted mean difference (WMD): -17.4 min, p<0.001), shorter ablation time (WMD: -6.6 min, p<0.001) and lower catheter irrigation fluid volume (WMD: -492.7 mL, p<0.001) than ST catheter. Pooled outcomes from four included studies with paroxysmal AF patients reported that using the STSF catheter for RFCA was associated with a significantly shorter ablation time (WMD: -5.7 min, p<0.001) and a lower risk of 1-year postablation arrhythmia recurrence (rate ratio: 0.504, p<0.001) than the SURROUNDFLOW (SF) catheter. Significant reductions in procedure time and ablation time associated with the STSF catheter were also reported in the other four studies using non-ST/SF catheters as the control. Overall complications of STSF catheter and control catheters were comparable. CONCLUSIONS: Using the STSF catheter was superior to using the ST catheter to conduct RFCA for AF by significantly reducing procedure time, ablation time, fluoroscopy time and irrigation fluid volume. The superiority of the STSF catheter over the SF catheter and other non-ST/SF catheters for RFCA needs further confirmation.

Pregnancy-induced physiological hypertrophic preconditioning attenuates pathological myocardial hypertrophy by activation of FoxO3a.

Previous studies show a woman's pregnancy is correlated with post-reproductive longevity, and nulliparity is associated with higher risk of incident heart failure, suggesting pregnancy likely exerts a cardioprotection. We previously reported a cardioprotective phenomenon termed myocardial hypertrophic preconditioning, but it is unknown whether pregnancy-induced physiological hypertrophic preconditioning (PHP) can also protect the heart against subsequent pathological hypertrophic stress. We aimed to clarify the phenomenon of PHP and its mechanisms. The pluripara mice whose pregnancy-induced physiological hypertrophy regressed and the nulliparous mice underwent angiotensin II (Ang II) infusion or transverse aortic constriction (TAC). Echocardiography, invasive left ventricular hemodynamic measurement and histological analysis were used to evaluate cardiac remodeling and function. Silencing or overexpression of Foxo3 by adeno-associated virus was used to investigate the role of FoxO3a involved in the antihypertrophic effect. Compared with nulliparous mice, pathological cardiac hypertrophy induced by Ang II infusion, or TAC was significantly attenuated and heart failure induced by TAC was markedly improved in mice with PHP. Activation of FoxO3a was significantly enhanced in the hearts of postpartum mice. FoxO3a inhibited myocardial hypertrophy by suppressing signaling pathway of phosphorylated glycogen synthase kinase-3ß (p-GSK3ß)/ß-catenin/Cyclin D1. Silencing or overexpression of Foxo3 attenuated or enhanced the anti-hypertrophic effect of PHP in mice with pathological stimulation. Our findings demonstrate that PHP confers resistance to subsequent hypertrophic stress and slows progression to heart failure through activation of FoxO3a/GSK3ß pathway.

Bioinformatics exploration of potential common therapeutic targets for systemic and pulmonary arterial hypertension-induced myocardial hypertrophy.

Systemic and pulmonary arterial hypertension (PAH) can induce left and right ventricular hypertrophy, respectively, but common therapeutic targets for both left and right hypertrophy are limited. In this study, we attempt to explore potential common therapeutic targets and screen out potential target drugs for further study. Cardiac mRNA expression profiles in mice with transverse aortic constriction (TAC) and pulmonary arterial constriction (PAC) are obtained from online databases. After bioinformatics analyses, we generate TAC and PAC mouse models to validate the phenotypes of cardiac remodelling as well as the identified hub genes. Bioinformatics analyses show that there are 214 independent differentially expressed genes (DEGs) in GSE136308 (TAC related) and 2607 independent DEGs in GSE30922 (PAC related), while 547 shared DEGs are associated with the function of the extracellular matrix (ECM) or involved in the PI3K-Akt signaling pathway, cytokine-cytokine receptor interactions, and ECM-receptor interactions. We identifyd Fn1, Il6, Col1a1, Igf1, Col1a2, Timp1, Col3a1, Cd44, Ctgf and Postn as hub genes of the shared DEGs, and most of them are associated with myocardial fibrosis. Those hub genes and phenotypes of cardiac remodelling are validated in our TAC and PAC mouse models. Furthermore, we identify dehydroisoandrosterone (DHEA), iloprost and 4,5-dianilinophthalimide (DAPH) as potential therapeutic drugs targeting both left and right ventricular hypertrophy and validate the effect of DHEA. These findings suggest that DHEA could be an effective drug for pressure overload-induced left or right ventricular hypertrophy by regulating the shared hub differentially expressed genes associated with fibrosis.

LCZ696 (sacubitril/valsartan) inhibits pulmonary hypertension induced right ventricular remodeling by targeting pyruvate dehydrogenase kinase 4.

BACKGROUND: Right ventricular (RV) function is a major prognostic factor in patients with cardiopulmonary disease. Effective medical therapies are available for left heart failure, but they are usually less effective or even ineffective in right heart failure. Here, we tested the hypothesis that LCZ696 (sacubitril/valsartan) can attenuate pressure overload-induced RV remodeling by inhibiting pyruvate dehydrogenase kinase 4 (PDK4). METHODS: Adult male C57 mice were subjected to transverse aortic constriction (TAC), pulmonary artery constriction (PAC), or sham surgery. Bioinformatics analysis was used to screen for common differentially expressed genes (DEGs) between TAC and PAC. Chemical compounds targeting DEGs were predicted by molecular docking analysis. Effects of LCZ696 on PAC-induced RV remodeling and the associated PDK4-related mechanisms were investigated. RESULTS: We found 60 common DEGs between PAC and TAC, and Pdk4 was one of the downregulated DEGs. From 47 chemical compounds with potential cardiovascular activity and PDK4 protein binding ability, we selected LCZ696 to treat PAC-induced RV remodeling because of its high docking score for binding PDK4. Compared with vehicle-treated PAC mice, LCZ696-treated mice had significantly smaller RV wall thickness and RV diameters, less myocardial fibrosis, lower expression of PDK4 protein, and less phosphorylation of glycogen synthase kinase-3ß (p-GSK3ß). In PAC mice, overexpression of Pdk4 blocked the inhibitory effect of LCZ696 on RV remodeling, whereas conditional knockout of Pdk4 attenuated PAC-induced RV remodeling. CONCLUSIONS: Pdk4 is a common therapeutic target for pressure overload-induced left ventricular and RV remodeling, and LCZ696 attenuates RV remodeling by downregulating Pdk4 and inhibiting PDK4/p-GSK3ß signal.

Circ-Ddx60 contributes to the antihypertrophic memory of exercise hypertrophic preconditioning.

INTRODUCTION: We previously reported a phenomenon called exercise hypertrophic preconditioning (EHP), the underlying mechanisms of which need further clarification. OBJECTIVES: We aimed to investigate whether circular RNAs (circRNAs) are involved in EHP. METHODS: CircRNA sequencing of myocardial tissue was performed in male C57BL/6 mice with EHP and sedentary. Bioinformatics analysis and Sanger sequencing were used to screen hub circRNA expression and to detect full-length circRNAs, respectively. Loss-of-function analyses were conducted to assess the effects of circ-Ddx60 (c-Ddx) on EHP. After 21 days of swimming training or resting, mice underwent transverse aortic constriction (TAC) or sham surgery. Echocardiography, invasive hemodynamic measurement and histological analysis were used to evaluate cardiac remodeling and function. The presence of interaction between c-Ddx and proteins was investigated using comprehensive identification of RNA-binding proteins by mass spectrometry (ChIRP-MS). RESULTS: In this study, we identified a novel circRNA, named c-Ddx that was preferentially expressed in myocardial tissue and significantly up-regulated in EHP mice. Silencing of c-Ddx attenuated the antihypertrophic effect of EHP and worsened heart failure in mice that underwent TAC. ChIRP-MS and molecular docking analysis validated the combination of c-Ddx and eukaryotic elongation factor 2 (eEF2). Mechanistically, c-Ddx silencing inhibited the increase of phosphorylation of eEF2 and its upstream AMP-activated protein kinase (AMPK) induced by EHP. CONCLUSIONS: C-Ddx contributes to the antihypertrophic memory of EHP by binding and activating eEF2, which would provide opportunity to search new therapeutic targets for pathological hypertrophy of heart.

Dapagliflozin attenuates residual cardiac remodeling after surgical ventricular reconstruction in mice with an enlarged heart after myocardial infarction.

BACKGROUND: Severe heart failure refractory to conventional therapy requires alternative treatment modalities. Surgical ventricular reconstruction (SVR) has been used to reverse cardiac remodeling in post-myocardial infarction (MI) patients with large left ventricular (LV) aneurysm, however, residual LV remodeling and dysfunction remain postoperatively. It is unclear whether SVR recovers response to drug treatment and whether the sodium-glucose co-transporter 2 inhibitor dapagliflozin (DAPA) reverses residual LV remodeling after SVR. METHODS: Adult male C57 mice were subjected to MI or sham surgery. Four-week later, MI mice with LV aneurysm underwent modified SVR or second open-chest sham operation and were randomized to DAPA or vehicle for four-week. Cardiac remodeling, LV function, and the underlying mechanisms were evaluated by echocardiography, invasive LV hemodynamic measurements, mRNA sequencing, and bioinformatics analysis. RESULTS: SVR significantly decreased LV volume; increased myocardial strain, LV pressure change rates and end-systolic elastance; and decreased heart-to-body weight ratio and myocardial fibrosis. However, significant residual cardiac remodeling remained. DAPA significantly attenuated residual cardiac remodeling and improved LV function in SVR mice but did not have curative effects in non-SVR mice. Of the 1532 genes differentially expressed in SVR and MI mice, 1037 were associated with cardiac metabolism; Src, Crebbp, Fn1, Grb2, and Mapk14 were the top 5 hub genes. Unlike sham surgery, MI upregulated those 5 genes, and treatment with SVR + DAPA normalized their expression. CONCLUSIONS: SVR restores therapeutic response in the post-MI heart with large LV aneurysm, and DAPA attenuates residual cardiac remodeling after SVR by normalizing some cardiac metabolism-related hub genes.

Revascularization of chronic total occlusion coronary artery and cardiac regeneration.

Coronary chronic total occlusion (CTO) contributes to the progression of heart failure in patients with ischemic cardiomyopathy. Randomized controlled trials demonstrated that percutaneous coronary intervention (PCI) for CTO significantly improves angina symptoms and quality of life but fails to reduce clinical events compared with optimal medical therapy. Even so, intervening physicians strongly support CTO-PCI. Cardiac regeneration therapy after CTO-PCI should be a promising approach to improving the prognosis of ischemic cardiomyopathy. However, the relationship between CTO revascularization and cardiac regeneration has rarely been studied, and experimental studies on cardiac regeneration usually employ rodent models with permanent ligation of the coronary artery rather than reopening of the occlusive artery. Limited early-stage clinical trials demonstrated that cell therapy for cardiac regeneration in ischemic cardiomyopathy reduces scar size, reverses cardiac remodeling, and promotes angiogenesis. This review focuses on the status quo of CTO-PCI in ischemic cardiomyopathy and the clinical prospect of cardiac regeneration in this setting.

CX3CL1 Worsens Cardiorenal Dysfunction and Serves as a Therapeutic Target of Canagliflozin for Cardiorenal Syndrome.

The prognosis of cardiorenal dysfunction induced by diabetes mellitus (DM), which belongs to cardiorenal syndrome type 5, is poor and its pathogenesis remains elusive. We have reported that CX3CL1 exacerbated heart failure and direct inhibition of CX3CL1 improved cardiac function. Emerging evidence supports that CX3CL1 is involved in renal impairment. Here we attempt to clarify whether CX3CL1 might be a therapeutic target for cardiorenal dysfunction in diabetes. We found that cardiac and renal CX3CL1 protein levels were significantly increased in both streptozotocin-induced diabetic mice and in non-obese diabetic mice, and that hyperglycemia led to persistent CX3CL1 expression in the heart and kidneys even after it was controlled by insulin. In cultured cardiac and renal cells, soluble CX3CL1 accelerated mitochondrial-dependent apoptosis via activation of the RhoA/ROCK1-Bax signaling pathway and promoted fibrosis through cellular phenotypic trans-differentiation mediated by the TGF-ß/Smad pathway. In the two diabetic mouse models, knockout of CX3CL1 receptor CX3CR1 or treatment with an CX3CL1 neutralizing antibody significantly improved cardiorenal dysfunction by inhibiting apoptosis, mitochondrial dysfunction, and fibrosis. Moreover, sodium glucose cotransporter 2 inhibitor canagliflozin significantly downregulated cardiac and renal CX3CL1 expression and improved cardiorenal dysfunction. These findings indicate that CX3CL1 could be a new therapeutic target for diabetes-induced cardiorenal dysfunction.

Generation and Characterization of Right Ventricular Myocardial Infarction Induced by Permanent Ligation of the Right Coronary Artery in Mice.

Right ventricular infarction (RVI) is a common presentation in clinical practice. Severe RVI can lead to fatal hemodynamic dysfunction and arrhythmia. In contrast to the extensively used mouse myocardial infarction (MI) model generated by left coronary artery ligation, the RVI mouse model is rarely employed due to the difficulty associated with model generation. Research on the mechanisms and treatment of RVI-induced RV remodeling and dysfunction requires animal models to mimic the pathophysiology of RVI in patients. This study introduces a feasible procedure for RVI model generation in C57BL/6J mice. Further, this model was characterized based on the following: infarct size evaluation at 24 h after MI, assessment of cardiac remodeling and function with echocardiography, RV hemodynamics assessment, and histology of the infarct zone at 4 weeks after RVI. In addition, a coronary vasculature cast was performed to observe the coronary arterial arrangement in RV. This mouse model of RVI would facilitate the research on mechanisms of right heart failure and seek new therapeutic targets of RV remodeling.

Growth differentiation factor 11 attenuates cardiac ischemia reperfusion injury via enhancing mitochondrial biogenesis and telomerase activity.

It has been reported that growth differentiation factor 11 (GDF11) protects against myocardial ischemia/reperfusion (IR) injury, but the underlying mechanisms have not been fully clarified. Considering that GDF11 plays a role in the aging/rejuvenation process and that aging is associated with telomere shortening and cardiac dysfunction, we hypothesized that GDF11 might protect against IR injury by activating telomerase. Human plasma GDF11 levels were significantly lower in acute coronary syndrome patients than in chronic coronary syndrome patients. IR mice with myocardial overexpression GDF11 (oe-GDF11) exhibited a significantly smaller myocardial infarct size, less cardiac remodeling and dysfunction, fewer apoptotic cardiomyocytes, higher telomerase activity, longer telomeres, and higher ATP generation than IR mice treated with an adenovirus carrying a negative control plasmid. Furthermore, mitochondrial biogenesis-related proteins and some antiapoptotic proteins were significantly upregulated by oe-GDF11. These cardioprotective effects of oe-GDF11 were significantly antagonized by BIBR1532, a specific telomerase inhibitor. Similar effects of oe-GDF11 on apoptosis and mitochondrial energy biogenesis were observed in cultured neonatal rat cardiomyocytes, whereas GDF11 silencing elicited the opposite effects to oe-GDF11 in mice. We concluded that telomerase activation by GDF11 contributes to the alleviation of myocardial IR injury through enhancing mitochondrial biogenesis and suppressing cardiomyocyte apoptosis.

Characterizing a long-term chronic heart failure model by transcriptomic alterations and monitoring of cardiac remodeling.

The long-term characteristics of transcriptomic alterations and cardiac remodeling in chronic heart failure (CHF) induced by myocardial infarction (MI) in mice are not well elucidated. This study aimed to reveal the dynamic changes in the transcriptome and cardiac remodeling in post-MI mice over a long time period. Monitoring C57BL/6 mice with MI for 8 months showed that approximately 44% of mice died of cardiac rupture in the first 2 weeks and others survived to 8 months with left ventricular (LV) aneurysm. The transcriptomic profiling analysis of cardiac tissues showed that the Integrin and WNT pathways were activated at 8 months after MI while the metabolism-related pathways were inversely inhibited. Subsequent differential analysis at 1 and 8 months post-MI revealed significant enrichments in biological processes, including consistent regulation of metabolism-related pathways. Moreover, echocardiographic monitoring showed a progressive increase in LV dimensions and a decrease in the LV fractional shortening during the first 4 weeks, and these parameters progressed at a lower rate till 8 months. A similar trend was found in the invasive LV hemodynamics, cardiac morphological and histological analyses. These results suggested that mouse MI model is ideal for long-term studies, and transcriptomic findings may provide new CHF therapeutic targets.

Antihypertrophic Memory After Regression of Exercise-Induced Physiological Myocardial Hypertrophy Is Mediated by the Long Noncoding RNA Mhrt779.

BACKGROUND: Exercise can induce physiological myocardial hypertrophy (PMH), and former athletes can live 5 to 6 years longer than nonathletic controls, suggesting a benefit after regression of PMH. We previously reported that regression of pathological myocardial hypertrophy has antihypertrophic effects. Accordingly, we hypothesized that antihypertrophic memory exists even after PMH has regressed, increasing myocardial resistance to subsequent pathological hypertrophic stress. METHODS: C57BL/6 mice were submitted to 21 days of swimming training to develop PMH. After termination of exercise, PMH regressed within 1 week. PMH regression mice (exercise hypertrophic preconditioning [EHP] group) and sedentary mice (control group) then underwent transverse aortic constriction or a sham operation for 4 weeks. Cardiac remodeling and function were evaluated with echocardiography, invasive left ventricular hemodynamic measurement, and histological analysis. LncRNA sequencing, chromatin immunoprecipitation assay, and comprehensive identification of RNA-binding proteins by mass spectrometry and Western blot were used to investigate the role of Mhrt779 involved in the antihypertrophic effect induced by EHP. RESULTS: At 1 and 4 weeks after transverse aortic constriction, the EHP group showed less increase in myocardial hypertrophy and lower expression of the Nppa and Myh7 genes than the sedentary group. At 4 weeks after transverse aortic constriction, EHP mice had less pulmonary congestion, smaller left ventricular dimensions and end-diastolic pressure, and a larger left ventricular ejection fraction and maximum pressure change rate than sedentary mice. Quantitative polymerase chain reaction revealed that the long noncoding myosin heavy chain-associated RNA transcript Mhrt779 was one of the markedly upregulated lncRNAs in the EHP group. Silencing of Mhrt779 attenuated the antihypertrophic effect of EHP in mice with transverse aortic constriction and in cultured cardiomyocytes treated with angiotensin II, and overexpression enhanced the antihypertrophic effect. Using chromatin immunoprecipitation assay and quantitative polymerase chain reaction, we found that EHP increased histone 3 trimethylation (H3K4me3 and H3K36me3) at the a4 promoter of Mhrt779. Comprehensive identification of RNA-binding proteins by mass spectrometry and Western blot showed that Mhrt779 can bind SWI/SNF related, matrix associated, actin dependent regulator of chromatin, subfamily a, member 4 (Brg1) to inhibit the activation of the histone deacetylase 2 (Hdac2)/phosphorylated serine/threonine kinase (Akt)/phosphorylated glycogen synthase kinase 3ß(p-GSK3ß) pathway induced by pressure overload. CONCLUSIONS: Myocardial hypertrophy preconditioning evoked by exercise increases resistance to pathological stress via an antihypertrophic effect mediated by a signal pathway of Mhrt779/Brg1/Hdac2/p-Akt/p-GSK3ß.

Excessive fibroblast growth factor 23 promotes renal fibrosis in mice with type 2 cardiorenal syndrome.

Cardiorenal syndrome (CRS) has a high mortality, but its pathogenesis remains elusive. Fibroblast growth factor 23 (FGF23) is increased in both renal dysfunction and cardiac dysfunction, and FGF receptor 4 (FGFR4) has been identified as a receptor for FGF23. Deficiency of FGF23 causes growth retardation and shortens the lifespan, but it is unclear whether excess FGF23 is detrimental in CRS. This study sought to investigate whether FGF23 plays an important role in CRS-induced renal fibrosis. A mouse model of CRS was created by surgical myocardial infarction for 12 weeks. CRS mice showed a significant increase of circulatory and renal FGF23 protein levels, as well as an upregulation of p-GSK, active-ß-catenin, TGF-ß, collagen I and vimentin, a downregulation of renal Klotho expression and induction of cardiorenal dysfunction and cardiorenal fibrosis. These changes were enhanced by cardiac overexpression of FGF23 and attenuated by FGF receptor blocker PD173074 or ß-catenin blocker IGC001. In fibroblasts (NRK-49F), expression of FGFR4 rather than Klotho was detected. Recombinant FGF23 upregulated the expression of p-GSK, active-ß-catenin, TGF-ß, collagen I and vimentin proteins. These changes were attenuated by FGFR4 blockade with BLU9931 or ß-catenin blockade with IGC001. We concluded that FGF23 promotes CRS-induced renal fibrosis mediated by partly activating FGFR4/ß-catenin signaling pathway.

RNA interactions in right ventricular dysfunction induced type II cardiorenal syndrome.

Right ventricular (RV) dysfunction induced type II cardiorenal syndrome (CRS) has a high mortality rate, but little attention has been paid to this disease, and its unique molecular characteristics remain unclear. This study aims to investigate the transcriptomic expression profile in this disease and identify key RNA pairs that regulate related molecular signaling networks. We established an RV dysfunction-induced type II CRS mouse model by pulmonary artery constriction (PAC). PAC mice developed severe RV hypertrophy and fibrosis; renal atrophy and dysfunction with elevated creatinine were subsequently observed. Expression profiles in RV and kidney tissues were obtained by whole transcriptome sequencing, revealing a total of 741 and 86 differentially expressed (DE) mRNAs, 159 and 29 DEmiRNAs and 233 and 104 DEcircRNAs between RV and kidney tissue, respectively. Competing endogenous RNA (ceRNA) networks were established. A significant alteration in proliferative, fibrotic and metabolic pathways was found based on GO and KEGG analyses, and the network revealed key ceRNA pairs, such as novel_circ_002631/miR-181a-5p/Creb1 and novel_circ_002631/miR-33-y/Kpan6. These findings indicate that significantly dysregulated pathways in RV dysfunction induced type II CRS include Ras, PI3K/Akt, cGMP-PKG pathways, and thyroid metabolic pathways. These ceRNA pairs can be considered potential targets for the treatment of type II CRS.

A Modified Surgical Ventricular Reconstruction in Post-infarction Mice Persistently Alleviates Heart Failure and Improves Cardiac Regeneration.

Objectives: Large ventricular aneurysm secondary to myocardial infarction (MI) results in severe heart failure (HF) and limits the effectiveness of regeneration therapy, which can be improved by surgical ventricular reconstruction (SVR). However, the conventional SVR procedures do not yield optimal long-term outcome in post-MI rodents. We hypothesized that a modified SVR procedure without aggressive purse string suture would persistently alleviate HF and improve cardiac regeneration in post-MI mice. Methods: Adult male C57 mice were subjected to MI or sham surgery. Four weeks later, mice with MI underwent SVR or 2nd open-chest operation alone. SVR was performed by plicating the aneurysm with a single diagonal linear suture from the upper left ventricle (LV) to the right side of the apex. Cardiac remodeling, heart function and myocardial regeneration were evaluated. Results: Three weeks after SVR, the scar area, LV volume, and heart weight/body weight ratio were significantly smaller, while LV ejection fraction, the maximum rising and descending rates of LV pressure, LV contractility and global myocardial strain were significantly higher in SVR group than in SVR-control group. The inhibitory effects of SVR on LV remodeling and HF persisted for at least eight-week. SVR group exhibited improved cardiac regeneration, as reflected by more Ki67-, Aurora B- and PH3-positive cardiomyocytes and a higher vessel density around the plication area of the infarcted LV. Conclusions: SVR with a single linear suture results in a significant and sustained reduction in LV volume and improvement in both LV systolic and diastolic function as well as cardiac regeneration.

Bibliometric Study of Sodium Glucose Cotransporter 2 Inhibitors in Cardiovascular Research.

BACKGROUND: An increasing number of studies have shown that sodium glucose cotransporter 2 (SGLT2) inhibitors, initially used as antidiabetic agents, have cardiovascular (CV) benefits. However, few bibliometric analyses have examined this field systematically. Our study aimed to visualize the publications to determine the trends and hotspots in CV research on SGLT2 inhibitors. METHODS: Publications on SGLT2 inhibitors in cardiovascular research were retrieved from the Web of Science Core Collection. Microsoft Excel 2019, VOSviewer, and CiteSpace V were used to analyze and plot the references. RESULTS: On July 3, 2020, 1509 records of CV research on SGLT2 inhibitors published from 2013 to 2020 were retrieved. Nearly half were authored by American scholars, and most were published in Diabetes Obesity Metabolism, Cardiovascular Diabetology, and Diabetes Therapy. The USA was the leading driving force, with a strong academic reputation in this area. Inzucchi SE published the most related articles, while Neal B was cited the most frequently. All the top 10 co-cited references were in the leading co-cited journal, The New England Journal of Medicine. "Atherosclerotic cardiovascular event" was the leading research hotspot. The keywords "cardiac metabolism," "heart failure hospitalization," and "heart failure with preserved ejection fraction" appeared most recently as research frontiers. CONCLUSION: Most studies focused on clinical trial outcomes, such as cardiovascular death and heart failure (HF) hospitalization. The mechanisms of SGLT2 inhibitors, especially those related to cardiac metabolism, may soon become hotspots and should be closely monitored.

Operating Transverse Aortic Constriction with Absorbable Suture to Obtain Transient Myocardial Hypertrophy.

Based on twice transverse aortic constrictions (TACs) in mice, it is proved that myocardial hypertrophic preconditioning (MHP) could attenuate cardiomyocyte hypertrophy and slow down progression to heart failure. For novices, however, the MHP model is usually quite difficult to establish because of the technical obstacles in ventilator operation, opening the chest repeatedly, and bleeding caused by debanding. To facilitate this model, to increase the surgical success rate and to reduce the incidence of bleeding, we switched to absorbable sutures for the first TAC combing with a ventilator-free technique. Using a 2-week absorbable suture, we demonstrated that this procedure could cause significant myocardial hypertrophy in 2 weeks; and 4 weeks after surgery, myocardial hypertrophy was almost completely regressed to the baseline. Using this protocol, the operators could master the MHP model easily with a lower operation mortality.