Anserine, a Histidine-Containing Dipeptide, Suppresses Pressure Overload-Induced Systolic Dysfunction by Inhibiting Histone Acetyltransferase Activity of p300 in Mice.

Anserine, an imidazole dipeptide, is present in the muscles of birds and fish and has various bioactivities, such as anti-inflammatory and anti-fatigue effects. However, the effect of anserine on the development of heart failure remains unknown. We cultured primary cardiomyocytes with 0.03 mM to 10 mM anserine and stimulated them with phenylephrine for 48 h. Anserine significantly suppressed the phenylephrine-induced increases in cardiomyocyte hypertrophy, ANF and BNP mRNA levels, and histone H3K9 acetylation. An in vitro histone acetyltransferase (HAT) assay showed that anserine directly suppressed p300-HAT activity with an IC50 of 1.87 mM. Subsequently, 8-week-old male C57BL/6J mice were subjected to transverse aortic constriction (TAC) and were randomly assigned to receive daily oral treatment with anserine-containing material, Marine Active® (60 or 200 mg/kg anserine) or vehicle for 8 weeks. Echocardiography revealed that anserine 200 mg/kg significantly prevented the TAC-induced increase in left ventricular posterior wall thickness and the decrease in left ventricular fractional shortening. Moreover, anserine significantly suppressed the TAC-induced acetylation of histone H3K9. These results indicate that anserine suppresses TAC-induced systolic dysfunction, at least in part, by inhibiting p300-HAT activity. Anserine may be used as a pharmacological agent for human heart failure therapy.

The Cancer Therapy-Related Clonal Hematopoiesis Driver Gene Ppm1d Promotes Inflammation and Non-Ischemic Heart Failure in Mice.

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Gingival bleeding and pocket depth among smokers and the related changes after short-term smoking cessation.

BACKGROUND: Smoking is associated with the deteriorating health of the gingiva and periodontium. The long-term beneficial effects of smoking cessation on oral health are well known. However, the effects of short-term smoking cessation on gingival bleeding and periodontal pocket depth are unknown. The purpose of the present study was to determine the effects of short-term smoking cessation on gingival bleeding and periodontal pocket depth. METHODS: Dentate smokers with a mean age of 56.9 ± 14.4 years at an outpatient smoking cessation clinic participated in this study. A professional dentist checked the periodontal pocket depth and gingival bleeding. Patients visited the smoking cessation clinic on their first visit and 2, 4, 8, and 12 weeks (three months). The gingival assessment was re-performed in those who succeeded in smoking cessation 3 months after the baseline. RESULTS: The baseline data of 83 patients showed that an increase in pocket depth was associated with increasing age and the amount of smoking. A significant increase in gingival bleeding (p = .031) and increase in pocket depth (p = .046) were observed 3 months after the baseline in patients who successfully quit smoking (n = 14). CONCLUSION: Short-term smoking cessation increased periodontal pocket depth and gingival bleeding. These findings may reflect healing processes that occur in the healthy gingiva. IMPLICATIONS: Study findings will be useful to advise patients during smoking cessation programs. Dentists can inform patients that an initial increase in gingival bleeding and pocket depth could be associated with smoking cessation. Such advice will prevent patients from any apprehension that may cause them to recommence smoking.

Metformin suppresses phenylephrine-induced hypertrophic responses by inhibiting p300-HAT activity in cardiomyocytes.

INTRODUCTION: Heart failure is the final pathway for a wide spectrum of myocardial stress, including hypertension and myocardial infarction. However, the potential effects of metformin on cardiac hypertrophy are still unclear. PURPOSE: The purpose of this study was to investigate whether metformin leads to suppression of hypertrophic responses in cardiomyocytes. METHODS AND RESULTS: To investigate whether metformin inhibited p300-histone acetyltransferase (HAT), we performed an in vitro HAT assay. Metformin directly inhibited p300-mediated acetylation of histone-H3K9. To examine the effects of metformin on hypertrophic responses, cardiomyocytes prepared from neonatal rats were treated with metformin and stimulated with saline or phenylephrine (PE), a α1-adrenergic agonist for 48 h. PE stimulus showed an increase in cell size, myofibrillar organization, expression of the endogenous atrial natriuretic factor and brain natriuretic peptide genes, and acetylation of histone-H3K9 compared with saline-treated cells. These PE-induced changes were inhibited by metformin. Next, to examine the effect of metformin on p300-mediated hypertrophy, cardiomyocytes were transfected with expression vector of p300. Metformin significantly suppressed p300-induced hypertrophic responses and acetylation of histone-H3K9. CONCLUSIONS: The study demonstrates that metformin can suppress PE-induced and p300-mediated hypertrophic responses. Metformin may be useful for the treatment of patients with diabetes and heart failure.

Alpha Mangostin Derived from Garcinia magostana Linn Ameliorates Cardiomyocyte Hypertrophy and Fibroblast Phenotypes in Vitro.

Cardiac hypertrophy and fibrosis are significant risk factors for chronic heart failure (HF). Since pharmacotherapy agents targeting these processes have not been established, we investigated the effect of alpha-magostin (α-man) on cardiomyocyte hypertrophy and fibrosis in vitro. Primary cultured cardiomyocytes and cardiac fibroblasts were prepared from neonatal rats. After α-man treatment, phenylephrine (PE) and transforming growth factor-beta (TGF-ß) were added to the cardiomyocytes and cardiac fibroblasts to induce hypertrophic and fibrotic responses, respectively. Hypertrophic responses were assessed by measuring the cardiomyocyte surface area and hypertrophic gene expression levels. PE-induced phosphorylation of Akt, extracellular signal-regulated kinase (ERK)1/2, and p38 was examined by Western blotting. Fibrotic responses were assessed by measuring collagen synthesis, fibrotic gene expression levels, and myofibroblast differentiation. In addition, TGF-ß-induced reactive oxygen species (ROS) production was investigated. In cultured cardiomyocytes, α-man significantly suppressed PE-induced increases in the cardiomyocyte surface area, and the mRNA levels (atrial natriuretic factor (ANF) and brain natriuretic peptide (BNP)). Treatment with α-man significantly suppressed PE-induced Akt phosphorylation, but not ERK and p38 phosphorylation. In cultured cardiac fibroblasts, α-man significantly suppressed TGF-ß-induced increases in L-proline incorporation, mRNA levels (POSTN and alpha-smooth muscle actin (α-SMA)), and myofibroblast differentiation. Additionally, it significantly inhibited TGF-ß-induced reduced nicotinamide adenine dinucleotide phosphate oxidase4 (NOX4) expression and ROS production in cardiac fibroblasts. Treatment with α-man significantly ameliorates hypertrophy by inhibiting Akt phosphorylation in cardiomyocytes and fibrosis by inhibiting NOX4-generating ROS in fibroblasts. These findings suggest that α-man is a possible natural product for the prevention of cardiac hypertrophy and fibrosis.

Histone Acetylation Domains Are Differentially Induced during Development of Heart Failure in Dahl Salt-Sensitive Rats.

Histone acetylation by epigenetic regulators has been shown to activate the transcription of hypertrophic response genes, which subsequently leads to the development and progression of heart failure. However, nothing is known about the acetylation of the histone tail and globular domains in left ventricular hypertrophy or in heart failure. The acetylation of H3K9 on the promoter of the hypertrophic response gene was significantly increased in the left ventricular hypertrophy stage, whereas the acetylation of H3K122 did not increase in the left ventricular hypertrophy stage but did significantly increase in the heart failure stage. Interestingly, the interaction between the chromatin remodeling factor BRG1 and p300 was significantly increased in the heart failure stage, but not in the left ventricular hypertrophy stage. This study demonstrates that stage-specific acetylation of the histone tail and globular domains occurs during the development and progression of heart failure, providing novel insights into the epigenetic regulatory mechanism governing transcriptional activity in these processes.

Clinically Administered Doses of Pitavastatin and Rosuvastatin.

Clinical studies have indicated that 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, also known as statins, can potentially inhibit chronic heart failure. In the Stat-LVDF study, a difference was noted in terms of the effect of lipophilic pitavastatin (PTV) and hydrophilic rosuvastatin (RSV) on plasma BNP, suggesting that statin lipophilicity and pharmacokinetics change the pleiotropic effect on heart failure in humans. Therefore, we assessed the beneficial effects of PTV on hypertrophy in cardiac myocytes compared with RSV at clinically used doses. Cultured cardiomyocytes were stimulated with 30 µM phenylephrine (PE) in the presence of PTV (250 nM) or RSV (50 nM). These doses were calculated based on the maximum blood concentration of statins used in clinical situations in Japan. The results showed that PTV, but not RSV, significantly inhibits the PE-induced increase in cell size and leucine incorporation without causing cell toxicity. In addition, PTV significantly suppressed PE-induced mRNA expression of hypertrophic response genes. PE-induced ERK phosphorylation was inhibited by PTV, but not by RSV. Furthermore, PTV significantly suppressed the angiotensin-II-induced proline incorporation in primary cultured cardiac fibroblasts. In conclusion, a clinical dose of PTV was noted to directly inhibit cardiomyocyte hypertrophy and cardiac fibrosis, suggesting that lipophilic PTV can be a potential drug candidate against chronic heart failure.

Wnt5a-Mediated Neutrophil Recruitment Has an Obligatory Role in Pressure Overload-Induced Cardiac Dysfunction.

BACKGROUND: Although the complex roles of macrophages in myocardial injury are widely appreciated, the function of neutrophils in nonischemic cardiac pathology has received relatively little attention. METHODS: To examine the regulation and function of neutrophils in pressure overload-induced cardiac hypertrophy, mice underwent treatment with Ly6G antibody to deplete neutrophils and then were subjected to transverse aortic constriction. RESULTS: Neutrophil depletion diminished transverse aortic constriction-induced hypertrophy and inflammation and preserved cardiac function. Myeloid deficiency of Wnt5a, a noncanonical Wnt, suppressed neutrophil infiltration to the hearts of transverse aortic constriction-treated mice and produced a phenotype that was similar to the neutropenic conditions. Conversely, mice overexpressing Wnt5a in myeloid cells displayed greater hypertrophic growth, inflammation, and cardiac dysfunction. Neutrophil depletion reversed the Wnt5a overexpression-induced cardiac pathology and eliminated differences in cardiac parameters between wild-type and myeloid-specific Wnt5a transgenic mice. CONCLUSIONS: These findings reveal that Wnt5a-regulated neutrophil infiltration has a critical role in pressure overload-induced heart failure.

CRISPR-Mediated Gene Editing to Assess the Roles of Tet2 and Dnmt3a in Clonal Hematopoiesis and Cardiovascular Disease.

RATIONALE: Clonal hematopoiesis has been associated with increased mortality and cardiovascular disease. This condition can arise from somatic mutations in preleukemic driver genes within hematopoietic stem/progenitor cells. Approximately 40 candidate driver genes have been identified, but mutations in only 1 of these genes, TET2 (ten-eleven translocation-2), has been shown to casually contribute to cardiovascular disease in murine models. OBJECTIVE: To develop a facile system to evaluate the disease characteristics of different clonal hematopoiesis driver genes using lentivirus vector and CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/clustered regularly interspaced short palindromic repeat-associated 9) methodology. Using this methodology, evaluate whether Dnmt3a (DNA [cytosine-5]-methyltransferase 3a)-a commonly occurring clonal hematopoiesis driver gene-causally contributes to cardiovascular disease. METHODS AND RESULTS: Lentivirus vectors were used to deliver Cas9 and guide RNA to introduce inactivating mutations in Tet2 and Dnmt3a in lineage-negative bone marrow cells. After implantation into lethally irradiated mice, these cells were engrafted and gave rise to labeled blood cell progeny. When challenged with an infusion of Ang II (angiotensin II), mice with inactivating mutations in Tet2 or Dnmt3a displayed greater cardiac hypertrophy, diminished cardiac function, and greater cardiac and renal fibrosis. In comparison with Tet2, inactivation of Dnmt3a did not lead to detectable expansion of the mutant hematopoietic cells during the time course of these experiments. Tet2 inactivation promoted the expression of IL (interleukin) 1ß, IL-6, and Ccl5, whereas Dnmt3a inactivation promoted the expression of Cxcl1 (CXC chemokine ligand), Cxcl2, IL-6, and Ccl5 in a lipopolysaccharide-stimulated macrophage cell line. CONCLUSIONS: Experiments using lentivirus vector/CRISPR methodology provided evidence suggesting that inactivating DNMT3A mutations in hematopoietic cells contributes to cardiovascular disease. Comparative analyses showed that inactivation of Tet2 and Dnmt3 was similar in their ability to promote Ang II-induced cardiac dysfunction and renal fibrosis in mice. However, gene-specific actions were indicated by differences in kinetics of hematopoietic stem/progenitor cell expansion and different patterns of inflammatory gene expression.

Kosen-cha, a Polymerized Catechin-Rich Green Tea, as a Potential Functional Beverage for the Reduction of Body Weight and Cardiovascular Risk Factors: A Pilot Study in Obese Patients.

Previous studies have shown that green tea catechins (GTCs) have beneficial effects on obesity and metabolic syndromes. In this study, we prepared kosen-cha from green tea using high pressure extraction, to reduce the astringent taste of the green tea. We identified a large quantity of polymerized GTCs in kosen-cha. To investigate the effects of kosen-cha containing polymerized GTCs in obese Japanese patients, we designed an open-label pilot study in which 6 obese subjects (body mass index (BMI) >25 kg/m2) were administered kosen-cha (5 g/L/d) for 12 weeks. Body composition, serum lipids, insulin resistance, vascular functions, and cardiac hypertrophy were measured before and 12 weeks after kosen-cha administration. Kosen-cha showed no significant adverse effects on the patients. Body weights, BMI, waist circumferences, serum triglyceride (TG) levels, and homeostasis model assessment as an index of insulin resistance (HOMA-IR) levels were significantly decreased after the 12 weeks of administration. Flow-mediated dilation (FMD) (p = 0.0214), brachial-ankle pulse wave velocity (baPWV)(p = 0.0141), left ventricular mass indexes (p = 0.0120), and plasma brain natriuretic peptide (BNP) (p = 0.0144) were significantly improved. Overall, kosen-cha reduced obesity and improved insulin resistance, vascular function, and cardiac hypertrophy, indicating its preventive potential in obesity and metabolic syndrome.

Cacao Bean Polyphenols Inhibit Cardiac Hypertrophy and Systolic Dysfunction in Pressure Overload-induced Heart Failure Model Mice.

Pathological stresses such as pressure overload and myocardial infarction induce cardiac hypertrophy, which increases the risk of heart failure. Cacao bean polyphenols have recently gained considerable attention for their beneficial effects on cardiovascular diseases. This study investigated the effect of cacao bean polyphenols on the development of cardiac hypertrophy and heart failure. Cardiomyocytes from neonatal rats were pre-treated with cacao bean polyphenols and then stimulated with 30 µM phenylephrine. C57BL/6j male mice were subjected to sham or transverse aortic constriction surgery and then orally administered with vehicle or cacao bean polyphenols. Cardiac hypertrophy and function were examined by echocardiography. In cardiomyocytes, cacao bean polyphenols significantly suppressed phenylephrine-induced cardiomyocyte hypertrophy and hypertrophic gene transcription. Extracellular signal-regulated kinase 1/2 and GATA binding protein 4 phosphorylation induced by phenylephrine was inhibited by cacao bean polyphenols treatment in the cardiomyocytes. Cacao bean polyphenols treatment at 1200 mg/kg significantly ameliorated left ventricular posterior wall thickness, fractional shortening, hypertrophic gene transcription, cardiac hypertrophy, cardiac fibrosis, and extracellular signal-regulated kinase 1/2 phosphorylation induced by pressure overload. In conclusion, these findings suggest that cacao bean polyphenols prevent pressure overload-induced cardiac hypertrophy and systolic dysfunction by inhibiting the extracellular signal-regulated kinase 1/2-GATA binding protein 4 pathway in cardiomyocytes. Thus, cacao bean polyphenols may be useful for heart failure therapy in humans.

Curcumin and its demethoxy derivatives possess p300 HAT inhibitory activity and suppress hypertrophic responses in cardiomyocytes.

The natural compound, curcumin (CUR), possesses several pharmacological properties, including p300-specific histone acetyltransferase (HAT) inhibitory activity. In our previous study, we demonstrated that CUR could prevent the development of cardiac hypertrophy by inhibiting p300-HAT activity. Other major curcuminoids isolated from Curcuma longa including demethoxycurcumin (DMC) and bisdemethoxycurcumin (BDMC) are structural analogs of CUR. In present study, we first confirmed the effect of these three curcuminoid analogs on p300-HAT activity and cardiomyocyte hypertrophy. Our results showed that DMC and BDMC inhibited p300-HAT activity and cardiomyocyte hypertrophy to almost the same extent as CUR. As the three compounds have structural differences in methoxy groups at the 3-position of their phenol rings, our results suggest that these methoxy groups are not involved in the inhibitory effects on p300-HAT activity and cardiac hypertrophy. These findings provide useful insights into the structure-activity relationship and biological activity of curcuminoids for p300-HAT activity and cardiomyocyte hypertrophy.

Effects of Products Containing Bacillus subtilis var. natto on Healthy Subjects with Neck and Shoulder Stiffness, a Double-Blind, Placebo-Controlled, Randomized Crossover Study.

Neck and shoulder stiffness is a typical subjective symptom in developed countries. This stiffness is caused by factors such as muscle tension and poor blood flow, leading to reduce work efficiency and diminish QOL. NKCP®, a natto-derived dietary food supplement whose main component is bacillopeptidase F, has antithrombotic, fibrinolytic, and blood viscosity-lowering effects. Here, we investigated the effect of NKCP® on neck and shoulder stiffness in a double-blind placebo-controlled randomized crossover study. Thirty subjects with neck and shoulder stiffness were randomly divided into 2 groups and ingested 250 mg of NKCP® or placebo daily for 4 weeks. Headache score significantly improved in the NKCP® group compared to the placebo group. Moreover, NKCP® significantly improved the score of visual analogue scale for neck and shoulder stiffness and pain, reduced muscle stiffness of the neck, and increased the skin surface temperature of neck and shoulders, compared to before ingestion. No adverse effects were observed during this study. These results suggest that NKCP® may alleviate headaches and chronic neck and shoulder stiffness and pain.

Secreted Frizzled-related Protein 5 Diminishes Cardiac Inflammation and Protects the Heart from Ischemia/Reperfusion Injury.

Wnt signaling has diverse actions in cardiovascular development and disease processes. Secreted frizzled-related protein 5 (Sfrp5) has been shown to function as an extracellular inhibitor of non-canonical Wnt signaling that is expressed at relatively high levels in white adipose tissue. The aim of this study was to investigate the role of Sfrp5 in the heart under ischemic stress. Sfrp5 KO and WT mice were subjected to ischemia/reperfusion (I/R). Although Sfrp5-KO mice exhibited no detectable phenotype when compared with WT control at baseline, they displayed larger infarct sizes, enhanced cardiac myocyte apoptosis, and diminished cardiac function following I/R. The ischemic lesions of Sfrp5-KO mice had greater infiltration of Wnt5a-positive macrophages and greater inflammatory cytokine and chemokine gene expression when compared with WT mice. In bone marrow-derived macrophages, Wnt5a promoted JNK activation and increased inflammatory gene expression, whereas treatment with Sfrp5 blocked these effects. These results indicate that Sfrp5 functions to antagonize inflammatory responses after I/R in the heart, possibly through a mechanism involving non-canonical Wnt5a/JNK signaling.

Tyrosine phosphorylation of RACK1 triggers cardiomyocyte hypertrophy by regulating the interaction between p300 and GATA4.

The zinc finger protein GATA4 is a transcription factor involved in cardiomyocyte hypertrophy. It forms a functional complex with the intrinsic histone acetyltransferase (HAT) p300. The HAT activity of p300 is required for the acetylation and transcriptional activity of GATA4, as well as for cardiomyocyte hypertrophy and the development of heart failure. In the present study, we have identified Receptor for Activated Protein Kinase C1 (RACK1) as a novel GATA4-binding protein using tandem affinity purification and mass spectrometry analyses. We found that exogenous RACK1 repressed phenylephrine (PE)-induced hypertrophic responses, such as myofibrillar organization, increased cell size, and hypertrophy-associated gene transcription, in cultured cardiomyocytes. RACK1 physically interacted with GATA4 and the overexpression of RACK1 reduced PE-induced formation of the p300/GATA4 complex and the acetylation and DNA binding activity of GATA4. In response to hypertrophic stimulation in cultured cardiomyocytes and in the hearts of hypertensive heart disease model rats, the tyrosine phosphorylation of RACK1 was increased, and the binding between GATA4 and RACK1 was reduced. In addition, the tyrosine phosphorylation of RACK1 was required for the disruption of the RACK1/GATA4 complex and for the formation of the p300/GATA4 complex. These findings demonstrate that RACK1 is involved in p300/GATA4-dependent hypertrophic responses in cardiomyocytes and is a promising therapeutic target for heart failure.

Regulation of Cardiac Transcription Factor GATA4 by Post-Translational Modification in Cardiomyocyte Hypertrophy and Heart Failure.

Heart failure is a leading cause of cardiovascular mortality in industrialized countries. During development and deterioration of heart failure, cardiomyocytes undergo maladaptive hypertrophy, and changes in the cellular phenotype are accompanied by reinduction of the fetal gene program. Gene expression in cardiomyocytes is regulated by various nuclear transcription factors, co-activators, and co-repressors. The zinc finger protein GATA4 is one such transcription factor involved in the regulation of cardiomyocyte hypertrophy. In response to hypertrophic stimuli such as those involving the sympathetic nervous and renin-angiotensin systems, changes in protein interaction and/or post-translational modifications of GATA4 cause hypertrophic gene transcription in cardiomyocytes. In this article, we focus on cardiac nuclear signaling molecules, especially GATA4, that are promising as potential targets for heart failure therapy.

Effects of Statins on Left Ventricular Diastolic Function in Patients with Dyslipidemia and Diastolic Dysfunction (Stat-LVDF Study).

Statins, 3-hydroxy-3-methylglutaryl (HMG)-CoA reductase inhibitors, are potential drugs for chronic heart failure treatment in clinical studies. However, there may be differences in the effects on heart failure between lipophilic and hydrophilic statins. In this study, we investigated whether hydrophilic rosuvastatin (RSV) and lipophilic pitavastatin (PTV) exert different effects on the left ventricular diastolic function. Subjects were hypercholesterolemia patients with left ventricular diastolic dysfunction. This was an open-label, randomized, parallel, comparative, prospective study. The subjects received treatment with RSV or PTV for 24 weeks, and their low density lipoprotein (LDL)-cholesterol levels were controlled by these statins according to the guideline. The primary endpoint was defined as the change in left ventricle (LV) diastolic function (E/E') estimated by echocardiography, and the secondary endpoint was the plasma B-type natriuretic peptide (BNP) level. No serious adverse effects were observed during the entire study period in any patient, nor were there any significant differences in changes in the body mass index, blood pressure, or heart rate. Statin treatment did not significantly alter the primary endpoint, E/E'. The change ratio of BNP was not significantly different between PTV and RSV groups. However, BNP was significantly increased in the RSV (p=0.030) but not the PTV (p>0.999) group. This study revealed that although neither RSV nor PTV improved LV diastolic dysfunction, BNP, a biomarker of LV wall stress, was increased in the RSV but not the PTV group. Observation for a longer period is necessary to clarify the different effects of these statins on LV diastolic dysfunction. (UMIN-ID: UMIN000003571).

Optimal dose-setting study of curcumin for improvement of left ventricular systolic function after myocardial infarction in rats.

A natural p300-specific histone acetyltransferase inhibitor, curcumin, may have a therapeutic potential for heart failure. However, a study of curcumin to identify an appropriate dose for heart failure has yet to be performed. Rats were subjected to a left coronary artery ligation. One week later, rats with a moderate severity of myocardial infarction (MI) were randomly assigned to 4 groups receiving the following: a solvent as a control, a low dose of curcumin (0.5 mg∙kg(-1)∙day(-1)), a medium dose of curcumin (5 mg∙kg(-1)∙day(-1)), or a high dose of curcumin (50 mg∙kg(-1)∙day(-1)). Daily oral treatment was continued for 6 weeks. After treatment, left ventricular (LV) fractional shortening was dose-dependently improved in the high-dose (25.2% ± 1.6%, P < 0.001 vs. vehicle) and medium-dose (19.6% ± 2.4%) groups, but not in the low-dose group (15.5% ± 1.4%) compared with the vehicle group (15.1% ± 0.8%). The histological cardiomyocyte diameter and perivascular fibrosis as well as echocardiographic LV posterior wall thickness dose-dependently decreased in the groups receiving high and medium doses. The beneficial effects of oral curcumin on the post-MI LV systolic function are lower at 5 compared to 50 mg∙kg(-1)∙day(-1) and disappear at 0.5 mg∙kg(-1)∙day(-1). To clinically apply curcumin therapy for heart failure patients, a precise, optimal dose-setting study is required.

Impact of smoking initiation age on nicotine dependency and cardiovascular risk factors: a retrospective cohort study in Japan.

Aims: Initiating smoking in early adolescence results in challenges with smoking cessation and is associated with high risk of cardiovascular disease. Recently, the initiation of smoking has transitioned from adolescence to young adulthood. However, there are few reports on the impact of initiating smoking at a later age. This study investigated the impact of the age of smoking initiation on nicotine dependency, smoking cessation rates, and cardiovascular risk factors, using a cut-off point of 20 years, within the Japanese population. Methods and results: This retrospective cohort study encompassed 1382 smokers who sought smoking cessation treatment at Kyoto Medical Centre Hospital between 2007 and 2019. Clinical indicators were evaluated by adjusting for age at the time of hospital visit and sex. The smoking cessation rate was further adjusted for treatment medication. The group with a smoking initiation age of <20 years reported a higher number of cigarettes/day (P = 0.002), higher respiratory carbon monoxide levels (P < 0.001), a higher Fagerström Test for Nicotine Dependence (FTND) score (P < 0.001), and a higher Self-rating Depression Scale score (P = 0.014). They also reported lower diastolic blood pressure (P = 0.020) and a lower successful smoking cessation rate [odds ratio: 0.736, 95% confidence interval (0.569, 0.951)] than the group with a smoking initiation age of ≥20 years. When smokers were divided into four groups based on the age they started smoking, the FTND score for those who started at 20-21 years was significantly higher than the score for those who started at 22 years or older. Conclusion: In young adulthood, initiating smoking later (beyond 20 years old) was associated with lower nicotine dependency and fewer depressive tendencies, as well as a higher success rate in smoking cessation among Japanese smokers. The results might suggest that raising the legal smoking initiation age from 20 to 22 years old or older could be effective in reducing nicotine dependency in smokers.

Fibroblast-specific PRMT5 deficiency suppresses cardiac fibrosis and left ventricular dysfunction in male mice.

Protein arginine methyltransferase 5 (PRMT5) is a well-known epigenetic regulatory enzyme. However, the role of PRMT5-mediated arginine methylation in gene transcription related to cardiac fibrosis is unknown. Here we show that fibroblast-specific deletion of PRMT5 significantly reduces pressure overload-induced cardiac fibrosis and improves cardiac dysfunction in male mice. Both the PRMT5-selective inhibitor EPZ015666 and knockdown of PRMT5 suppress α-smooth muscle actin (α-SMA) expression induced by transforming growth factor-ß (TGF-ß) in cultured cardiac fibroblasts. TGF-ß stimulation promotes the recruitment of the PRMT5/Smad3 complex to the promoter site of α-SMA. It also increases PRMT5-mediated H3R2 symmetric dimethylation, and this increase is inhibited by Smad3 knockdown. TGF-ß stimulation increases H3K4 tri-methylation mediated by the WDR5/MLL1 methyltransferase complex, which recognizes H3R2 dimethylation. Finally, treatment with EPZ015666 significantly improves pressure overload-induced cardiac fibrosis and dysfunction. These findings suggest that PRMT5 regulates TGF-ß/Smad3-dependent fibrotic gene transcription, possibly through histone methylation crosstalk, and plays a critical role in cardiac fibrosis and dysfunction.