Amelioration of circadian disruption and calcium-handling protein defects by choline alleviates cardiac remodeling in abdominal aorta coarctation rats

CELF1 Promotes Post-myocardial Infarction Cardiac Remodeling Via Suppression of FMO2

Post-myocardial infarction (MI) cardiac remodeling ultimately causes heart failure. We explored how CUG-binding protein Elav-like family member 1 (CELF1) affected post-MI cardiac remodeling. Mice underwent MI induction by left anterior descending artery (LAD) ligation and short hairpin-CELF1, overexpressing-flavin-containing monooxygenase 2 (FMO2) lentivirus and transforming growth factor-β1 (TGF-β1) treatments. Mouse cardiac fibroblasts were cultured in vitro, followed by fibrosis induction with TGF-β1. Left ventricular ejection fraction, left ventricular end-diastolic volume and left ventricular end-systolic volume were tested by ultrasound cardiography. Heart weight/body weight was determined. CELF1 and FMO2 mRNA levels, pathologic changes, collagen deposition and myocardial fibrosis of cardiac tissues, cardiomyocyte area, myocardial apoptosis, and myocardial CELF1, FMO2, collagen I, fibronectin, and elastin levels were assessed by RT-qPCR, HE, Masson, WGA, TUNEL staining, and immunohistochemistry. CELF1-FMO2 interaction was confirmed using RNAct database and RIP assay. The biotinylated GU-rich element of FMO2 mRNA-CELF1 binding and mRNA stability were assayed by RNA pull-down and actinomycin D assays. LAD ligation induced cardiac remodeling [cardiac enlargement, myocardial tissue damage, increased myocardial collagen fiber tissues, poor cardiac function, cardiomyocyte hypertrophy, myocardial apoptosis, and extracellular matrix (ECM) deposition]. CELF1 was up-regulated in post-MI mouse myocardial tissues. CELF1 silencing up-regulated FMO2 and improved previously-mentioned conditions in MI mice, which were partially reversed by inducing ECM deposition. CELF1 down-regulated FMO2 and promoted FMO2 mRNA decay through interaction with FMO2 and FMO2 mRNA 3'UTR, respectively. FMO2 overexpression improved ECM deposition and cardiac remodeling in MI mice. CELF1 facilitates post-MI cardiac remodeling through FMO2 inhibition.

The Role of Muscarinic Acetylcholine Receptor M3 in Cardiovascular Diseases

The muscarinic acetylcholine receptor M3 (M3-mAChR) is involved in various physiological and pathological processes. Owing to specific cardioprotective effects, M3-mAChR is an ideal diagnostic and therapeutic biomarker for cardiovascular diseases (CVDs). Growing evidence has linked M3-mAChR to the development of multiple CVDs, in which it plays a role in cardiac protection such as anti-arrhythmia, anti-hypertrophy, and anti-fibrosis. This review summarizes M3-mAChR's expression patterns, functions, and underlying mechanisms of action in CVDs, especially in ischemia/reperfusion injury, cardiac hypertrophy, and heart failure, opening up a new research direction for the treatment of CVDs.

An inverse association of dietary choline with atherosclerotic cardiovascular disease among US adults: a cross-sectional NHANES analysis

BACKGROUND

The role of diet choline in atherosclerotic cardiovascular disease (ASCVD) is uncertain. Findings from animal experiments are contradictory while there is a lack of clinical investigations. This study aimed to investigate the association between choline intake and ASCVD based on individuals from the National Health and Nutrition Examination Survey (NHANES) database.

METHODS

This cross-sectional study was conducted in 5525 individuals from the NHANES between 2011 and 2018. Participants were categorized into the ASCVD (n = 5015) and non-ASCVD (n = 510) groups. Univariable and multivariable-adjusted regression analyses were employed to investigate the relationship between diet choline and pertinent covariates. Logistic regression analysis and restricted cubic spline analysis were used to evaluate the association between choline intake and ASCVD.

RESULTS

ASCVD participants had higher choline intake compared to those without ASCVD. In the higher tertiles of choline intake, there was a greater proportion of males, married individuals, highly educated individuals, and those with increased physical activity, but a lower proportion of smokers and drinkers. In the higher tertiles of choline intake, a lower proportion of individuals had a history of congestive heart failure and stroke. After adjusting for age, gender, race, ethnicity, and physical activity, an inverse association between choline intake and heart disease, stroke, and ASCVD was found. A restricted cubic spline analysis showed a mirrored J-shaped relationship between choline and ASCVD, stroke and congestive heart failure in males. There was no association between dietary choline and metabolic syndrome.

CONCLUSION

An inverse association was observed between choline intake and ASVCD among U.S. adults. Further large longitudinal studies are needed to test the causal relationship of choline and ASVCD.

A murine model of hypertensive heart disease in older women

We propose a new mouse (C57Bl6/J) model combining several features of heart failure with preserved ejection fraction encountered in older women, including hypertension from Angiotensin II infusion (AngII), menopause, and advanced age. To mimic menopause, we delayed ovariectomy (Ovx) at 12 months of age. We also studied the effects of AngII infusion for 28 days in younger animals and the impact of losing gonadal steroids earlier in life. We observed that AngII effects on heart morphology were different in younger and adult mice (3- and 12-month-old; 20 and 19% increase in heart weight. P < 0.01 for both) than in older animals (24-month-old; 6%; not significant). Ovariectomy at 12 months restored the hypertrophic response to AngII in elderly females (23%, p = 0.0001). We performed a bulk RNA sequencing study of the left ventricle (LV) and left atrial gene expression in elderly animals, controls, and Ovx. AngII modulated (|Log2 fold change| ≥ 1) the LV expression of 170 genes in control females and 179 in Ovx ones, 64 being shared. In the left atrium, AngII modulated 235 genes in control females and 453 in Ovx, 140 shared. We observed many upregulated genes associated with the extracellular matrix regulation in both heart chambers. Many of these upregulated genes were shared between the ventricle and the atrium as well as in control and Ovx animals, namely for the most expressed Ankrd1, Nppb, Col3a1, Col1a1, Ctgf Col8a1, and Cilp. Several circadian clock LV genes were modulated differently by AngII between control and Ovx females (Clock, Arntl, Per2, Cry2, and Ciart). In conclusion, sex hormones, even in elderly female mice, modulate the heart's hypertrophic response to AngII. Our study identifies potential new markers of hypertensive disease in aging female mice and possible disturbances of their cardiac circadian clock.

The physiological role of TRP channels in sleep and circadian rhythm

TRP channels, are non-specific cationic channels that are involved in multiple physiological processes that include salivation, cellular secretions, memory extinction and consolidation, temperature, pain, store-operated calcium entry, thermosensation and functionality of the nervous system. Here we choose to look at the evidence that decisively shows how TRP channels modulate human neuron plasticity as it relates to the molecular neurobiology of sleep/circadian rhythm. There are numerous model organisms of sleep and circadian rhythm that are the results of the absence or genetic manipulation of the non-specific cationic TRP channels. Drosophila and mice that have had their TRP channels genetically ablated or manipulated show strong evidence of changes in sleep duration, sleep activity, circadian rhythm and response to temperature, noxious odours and pattern of activity during both sleep and wakefulness along with cardiovascular and respiratory function during sleep. Indeed the role of TRP channels in regulating sleep and circadian rhythm is very interesting considering the parallel roles of TRP channels in thermoregulation and thermal response with concomitant responses in growth and degradation of neurites, peripheral nerves and neuronal brain networks. TRP channels provide evidence of an ability to create, regulate and modify our sleep and circadian rhythm in a wide array of physiological and pathophysiological conditions. In the current review, we summarize previous results and novel recent advances in the understanding of calcium ion entry via TRP channels in different sleep and circadian rhythm conditions. We discuss the role of TRP channels in sleep and circadian disorders.

Preventive and Therapeutic Effects of Crocetin in Rats with Heart Failure

Gardenia is both a food and medicine plant. It is widely used for cardiovascular protection, and its main bioactive ingredient is crocetin. This study aims to observe the therapeutic effects of crocetin on chronic heart failure in rats induced by various etiologies. It further compares the efficacy differences between preventative and treatment administration, varying dosages, and treatment durations, to provide improved guidance for medication in heart failure rats and determine which categories of chronic heart failure rats might benefit most from crocetin. Chronic heart failure models induced by abdominal aorta constriction, renal hypertension, and coronary artery ligation were constructed. By examining cardiac function, blood biochemistry, and histopathology, the study assessed the preventive and therapeutic effects of crocetin on load-induced and myocardial ischemia-induced heart failure. The results showed that in all three models, both treatment and preventative administration of crocetin significantly improved chronic heart failure in rats, especially in preventative administration. The results indicate crocetin may be beneficial for improving symptoms and functional capacity in rats with heart failure. Furthermore, long-term administration was more effective than short-term administration across all three rat models, with therapeutic onset observed over 6 weeks.

Insight on Cardiac Chronobiology and Latest Developments of Chronotherapeutic Antihypertensive Interventions for Better Clinical Outcomes

Cardiac circadian rhythms are an important regulator of body functions, including cardiac activities and blood pressure. Disturbance of circadian rhythm is known to trigger and aggravate various cardiovascular diseases. Thus, modulating the circadian rhythm can be used as a therapeutic approach to cardiovascular diseases. Through this work, we intend to discuss the current understanding of cardiac circadian rhythms, in terms of quantifiable parameters like BP and HR. We also elaborate on the molecular regulators and the molecular cascades along with their specific genetic aspects involved in modulating circadian rhythms, with specific reference to cardiovascular health and cardiovascular diseases. Along with this, we also presented the latest pharmacogenomic and metabolomics markers involved in chronobiological control of the cardiovascular system along with their possible utility in cardiovascular disease diagnosis and therapeutics. Finally, we reviewed the current expert opinions on chronotherapeutic approaches for utilizing the conventional as well as the new pharmacological molecules for antihypertensive chronotherapy.

7,8-Dihydroxyflavone alleviates cardiac fibrosis by restoring circadian signals via downregulating Bmal1/Akt pathway

Brain-derived neurotrophic factor (BDNF)/tyrosine kinase receptor B (TrkB) pathway is a therapeutic target in cardiac diseases. A BDNF mimetic, 7,8-dihydroxyflavone (7,8-DHF), is emerging as a protective agent in cardiomyocytes; however, its potential role in cardiac fibroblasts (CFs) and fibrosis remains unknown. Thus, we aimed to explore the effects of 7,8-DHF on cardiac fibrosis and the possible mechanisms. Myocardial ischemia (MI) and transforming growth factor-β1 (TGF-β1) were used to establish models of cardiac fibrosis. Hematoxylin & eosin and Masson's trichrome stains were used for histological analysis and determination of collagen content in mouse myocardium. Cell viability kit, EdU (5-ethynyl-2'-deoxyuridine) assay and immunofluorescent stain were employed to examine the effects of 7,8-DHF on the proliferation and collagen production of CFs. The levels of collagen I, α-smooth muscle actin (α-SMA), TGF-β1, Smad2/3, and Akt as well as circadian rhythm-related signals including brain and muscle Arnt-like protein 1 (Bmal1), period 2 (Per2), and cryptochrome 2 (Cry2) were analyzed. Treatment with 7,8-DHF markedly alleviated cardiac fibrosis in MI mice. It inhibited the activity of CFs accompanied by decreasing number of EdU-positive cells and downregulation of collagen I, α-SMA, TGF-β1, and phosphorylation of Smad2/3. 7,8-DHF significantly restored the dysregulation of Bmal1, Per2, and Cry2, but inhibited the overactive Akt. Further, inhibition of Bmal1 by SR9009 effectively attenuated CFs proliferation and collagen production of CFs. In summary, these findings indicate that 7,8-DHF attenuates cardiac fibrosis and regulates circadian rhythmic signals, at least partly, by inhibiting Bmal1/Akt pathway, which may provide new insights into therapeutic cardiac remodeling.

Qiliqiangxin Capsule Modulates Calcium Transients and Calcium Sparks in Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes

Background

The therapeutic effects of Qiliqiangxin capsule (QLQX), a Chinese patent medicine, in patients with chronic heart failure are well established. However, whether QLQX modulates cardiac calcium (Ca²⁺) signals, which are crucial for the heart function, remains unclear. Aim of the Study. This study aimed to evaluate the role of QLQX in modulating Ca²⁺ signals in human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs).

Materials and Methods

Fluorescence imaging was used to monitor Ca²⁺ signals in the cytosol and nuclei of hiPSC-CMs. For Ca²⁺ spark measurements, the line-scan mode of a confocal microscope was used.

Results

The QLQX treatment substantially decreased the frequency of spontaneous Ca²⁺ transients, whereas the amplitude of Ca²⁺ transients elicited by electrical stimulation did not change. QLQX increased the Ca²⁺ spark frequency in both the cytosol and nuclei without changing the sarcoplasmic reticulum Ca²⁺ content. Interestingly, QLQX ameliorated abnormal Ca²⁺ transients in CMs differentiated from hiPSCs derived from patients with long-QT syndrome.

Conclusions

Our findings provide the first line of evidence that QLQX directly modulates cardiac Ca²⁺ signals in a human cardiomyocyte model.

Postnatal Deletion of Bmal1 in Cardiomyocyte Promotes Pressure Overload Induced Cardiac Remodeling in Mice

Background Mice with cardiomyocyte-specific deletion of Bmal1, a core clock gene, had spontaneous abnormal cardiac metabolism, dilated cardiomyopathy, and shortened lifespan. However, the role of cardiomyocyte Bmal1 in pressure overload induced cardiac remodeling is unknown. Here we aimed to understand the contribution of cardiomyocyte Bmal1 to cardiac remodeling in response to pressure overload induced by transverse aortic constriction or chronic angiotensin Ⅱ (AngⅡ) infusion. Methods and Results By generating a tamoxifen-inducible cardiomyocyte-specific Bmal1 knockout mouse line (cKO) and challenging the mice with transverse aortic constriction or AngⅡ, we found that compared to littermate controls, the cKO mice displayed remarkably increased cardiac hypertrophy and augmented fibrosis both after transverse aortic constriction and AngⅡ induction, as assessed by echocardiographic, gravimetric, histologic, and molecular analyses. Mechanistically, RNA-sequencing analysis of the heart after transverse aortic constriction exposure revealed that the PI3K/AKT signaling pathway was significantly activated in the cKOs. Consistent with the in vivo findings, in vitro study showed that knockdown of Bmal1 in cardiomyocytes significantly promoted phenylephrine-induced cardiomyocyte hypertrophy and triggered fibroblast-to-myofibroblast differentiation, while inhibition of AKT remarkedly reversed the pro-hypertrophy and pro-fibrosis effects of Bmal1 knocking down. Conclusions These results suggest that postnatal deletion of Bmal1 in cardiomyocytes may promote pressure overload-induced cardiac remodeling. Moreover, we identified PI3K/AKT signaling pathway as the potential mechanistic ties between Bmal1 and cardiac remodeling.

Mitochondrial homeostasis and redox status in cardiovascular diseases: Protective role of the vagal system

Mitochondria participate in essential cellular functions, including energy production, metabolism, redox homeostasis regulation, intracellular Ca²⁺ handling, apoptosis, and cell fate determination. Disruption of mitochondrial homeostasis under pathological conditions results in mitochondrial reactive oxygen species (ROS) generation and energy insufficiency, which further disturb mitochondrial and cellular homeostasis in a deleterious loop. Mitochondrial redox status has therefore become a potential target for therapy against cardiovascular diseases. In this review, we highlight recent progress in determining the roles of mitochondrial processes in regulating mitochondrial redox status, including mitochondrial dynamics (fusion-fission pathways), mitochondrial cristae remodeling, mitophagy, biogenesis, and mitochondrion-organelle interactions (endoplasmic reticulum-mitochondrion interactions, nucleus-mitochondrion communication, and lipid droplet-mitochondrion interactions). The strategies that activate vagal system include direct vagal activation (electrical vagal stimulation and administration of vagal neurotransmitter acetylcholine) and pharmacological modulation (choline and cholinesterase inhibitors). The vagal system plays an important role in maintaining mitochondrial homeostasis and suppressing mitochondrial oxidative stress by promoting mitochondrial biogenesis and mitophagy, moderating mitochondrial fusion and fission, strengthening mitochondrial cristae stabilization, regulating mitochondrion-organelle interactions, and inhibiting mitochondrial Ca²⁺ overload. Therefore, enhancement of vagal activity can maintain mitochondrial homeostasis and represents a promising therapeutic strategy for cardiovascular diseases.