永井 良三

BACKGROUND: In prior myocardial infarction (PMI) patients, diabetes mellitus (DM), dyslipidemia, and hypertension increase the risk of secondary cardiovascular events. Although a decreased ratio of serum eicosapentaenoic acid (EPA) to arachidonic acid (AA; EPA/AA) has been shown to significantly correlate with the onset of acute coronary syndrome, the associations between polyunsaturated fatty acid (PUFA) levels and coronary risk factors in PMI patients have not been evaluated thoroughly. This study aimed to assess the associations between PUFAs levels and the risk factors in PMI patients. METHODS: We enrolled 1733 patients with known PUFA levels who were treated in five divisions of cardiology in a metropolitan area of Japan, including 303 patients with PMI. EPA/AA and docosahexaenoic acid (DHA) to AA level ratio (DHA/AA) in patients with and without PMI were analyzed according to presence of coronary risk factors. RESULTS: Diabetes patients with PMI had significantly lower EPA/AA and DHA/AA than diabetes patients without PMI (EPA/AA: P <0.01; DHA/AA: P =0.003), with no such differences in dyslipidemia and hypertension patients. In DM patients with high high-sensitivity C-reactive protein (hs-CRP) levels (>0.1 mg/dL), EPA/AA was low in individuals who also had PMI, whereas DHA/AA was not (EPA/AA, with PMI: 0.43 ± 0.24; without PMI: 0.53 ± 0.30, P < 0.05). Moreover, patients on statins had significantly lower DHA/AA ratios, whereas the EPA/AA ratio did not depend on statin use. Multiple regression analysis revealed that statin use in DM patients was associated with low DHA/AA but not EPA/AA. CONCLUSION: PMI patients with DM have low EPA/AA and DHA/AA. EPA/AA and DHA/AA are differently related to hs-CRP level in DM patients with PMI. Statin use can potentially affect DHA/AA but not EPA/AA, and therefore EPA/AA ratio is a better marker of assessment for cardiovascular events.

Hepatic lipogenesis is nutritionally regulated (i.e., downregulated during fasting and upregulated during the postprandial state) as an adaptation to the nutritional environment. While alterations in the expression level of the transcription factor SREBP-1c are known to be critical for nutritionally regulated lipogenesis, upstream mechanisms governing Srebf1 expression remain unclear. Here, we show that the fasting-induced transcription factor KLF15, a key regulator of gluconeogenesis, forms a complex with LXR/RXR, specifically on the Srebf1 promoter. This complex recruits the corepressor RIP140 instead of the coactivator SRC1, resulting in reduced Srebf1 and thus downstream lipogenic enzyme expression during the early and euglycemic period of fasting prior to hypoglycemia and PKA activation. Through this mechanism, KLF15 overexpression specifically ameliorates hypertriglyceridemia without affecting LXR-mediated cholesterol metabolism. These findings reveal a key molecular link between glucose and lipid metabolism and have therapeutic implications for the treatment of hyperlipidemia.

BACKGROUND: A low eicosapentaenoic acid (EPA) to arachidonic acid (AA) ratio is a known risk for acute coronary syndrome (ACS). However, the association between the docosahexaenoic acid (DHA) to AA ratio and ACS remains unclear. This study aimed to assess the association between the DHA/AA ratio and ACS by patient characteristics. METHODS: We enrolled 1733 patients and evaluated the serum levels of polyunsaturated fatty acids in 5 cardiology departments in a metropolitan area of Japan. We assessed the relationship between the DHA/AA ratio (median cut-off value: 0.903) and ACS according to the following 10 subgroups: sex, age, diabetes mellitus, hypertension, dyslipidemia, smoking history, family history of ischemic heart disease, chronic kidney disease, obesity, and history of coronary revascularization. RESULTS: Interaction tests in the 10 subgroup analyses revealed a significant difference for adjusted log odds ratios between male and females (p = 0.01), and those with and without hypertension (p = 0.06). Especially in the subgroup based on sex difference, a high DHA/AA ratio was significantly associated with a low risk of ACS among men (adjusted odds ratio = 0.389; 95 % confidence interval: 0.211-0.716). In contrast, a reverse association was found among women, although this was not statistically significant (adjusted odds ratio = 3.820; 95 % confidence interval: 0.718-20.325). CONCLUSIONS: The association between the DHA/AA ratio and ACS differed by clinical characteristic. Notably, patients with a low DHA/AA ratio had a higher risk of ACS than those with a high DHA/AA ratio, and this was significant for men in particular.

In early age-related macular degeneration (AMD), complement component C3 can be observed in drusen, which is the accumulation of material beneath the retinal pigment epithelium. The complement pathways, via the activation of C3, can upregulate the expression of cytokines and their receptors and the recruitment of inflammatory leukocytes, both of which play an important role in the development of choroidal neovascularization (CNV) in exudative AMD. Laser-induced CNV lesions were found to be significantly smaller in C3(-/-) mice than in wild-type mice. By using flow cytometry, we demonstrated that the proportions of intraocular granulocytes, CD11b(+)F4/80(+)Ly6C(hi) and CD11b(+)F4/80(+)Ly6C(lo) cells, were lower in C3(-/-) mice than in wild-type mice as early as day 1 after laser injury, and the proportions of granulocytes and three macrophage/monocyte subsets were significantly lower on day 3. In contrast, C3(-/-) mice had more granulocytes and CD11b(+)F4/80(+)Ly6C(hi) cells in peripheral blood than wild-type mice after injury. Further, the expression levels of Vegfa164 were upregulated in intraocular Ly6C(hi) macrophages/monocytes of C3(-/-) mice, but not as much as in wild-type mice. Collectively, our data demonstrate that despite a more pronounced induction of systemic inflammation, inhibition of complement factor C3 suppresses CNV by decreasing the recruitment of inflammatory cells to the lesion.

Speckle tracking echocardiography (STE) has been reported to be a promising technique for evaluating right ventricular (RV) function in the clinical setting. On the other hand, the usefulness of STE for RV evaluation in small animal models has not been clarified, although the rat model is among the most commonly used animal models to develop novel effective treatments against pulmonary hypertension and RV heart failure (HF).We validated the use of STE and conventional echocardiographic variables for evaluating RV functions in a rat model by comparing the echocardiographic values of RVHF rats (n = 12) induced by monocrotaline injection with those of control rats (n = 12).Most conventional echocardiographic variables demonstrated that RVHF rats have significant RV dysfunction. The area under the curve (AUC) values to distinguish RV dysfunction in RVHF rats from normal RV function in control rats using fractional area change (FAC), tricuspid annular plane systolic excursion (TAPSE), RV myocardial performance index (MPI), peak tissue Doppler tricuspid annular velocities at systole (Sa), and at early diastole (Ea) were 0.71, 0.98, 0.79, 0.92, and 0.91, respectively. However, using STE analysis for RV evaluation, limited reproducibility was observed (variability 19-37 %, ICC 0.74-0.88) and the only circumferential strain showed significantly lower absolute values (P = 0.039, AUC = 0.76).To evaluate RV function in rat models, circumferential strain may be useful, however, the reproducibility and diagnostic utility were limited. Conventional echocardiographic variables such as TAPSE, tissue Doppler Sa, and Ea have superior diagnostic utility.

BACKGROUND: Therapeutic strategies for pulmonary arterial hypertension (PAH) associated with atrial septal defect (ASD) remain a matter of debate. METHODS AND RESULTS: We identified 5 outpatients who had been diagnosed with ASD-PAH and undergone ASD closure in combination with targeted therapy with certified PAH drugs. We assessed changes in hemodynamic parameters and exercise capacity. The combination of ASD closure and targeted therapy significantly increased systemic blood flow (Qs) from the baseline (from 3.3 ± 0.6 L/minute to 4.2 ± 1.0 L/minute, P < 0.05) with a significant improvement in the World Health Organization Functional Class (WHO-FC; from 2.8 ± 0.4 to 1.6 ± 0.5, P < 0.05). The hemodynamic data before and after ASD closure without targeted therapy showed further elevation of pulmonary vascular resistance shortly after ASD closure (678 dyne · s/cm(5) to 926 dyne · s/cm(5)) in 1 case, as well as after a long time since ASD closure (491.0 ± 53.7 dyne · s/cm(5) to 1045.0 ± 217.8 dyne · s/cm(5)) in 2 cases. This worsening was reversed after the targeted therapy, accompanied by an increase in Qs and an improvement in WHO-FC in all cases. CONCLUSIONS: Targeted therapy should be added to ASD closure in adult patients with ASD-PAH.

Oxidative stress has been implicated in cardiac remodeling (cardiac fibrosis and hypertrophy), which impairs cardiac function and metabolism; therefore, it is anticipated antioxidative compounds will have protective properties against cardiac remodeling. Luteolin (3',4',5,7-tetrahydroxyflavone), a widely distributed flavonoid found in many herbal extracts including celery, green pepper, perilla leaves and seeds, and chamomile, is a known to be a potent antioxidant and was previously demonstrated to exert an antifibrotic effect in the lungs and the liver. In this study, we clearly demonstrate that oral pretreatment with the higher-luteolin diet (0.035% (wt/wt)) protected against cardiac fibrosis and hypertrophy as well as a hyperoxidative state in Ang II-infused rats. In cardiac tissue, increased gene expression levels of TGFβ1, CTGF, Nox2, Nox4, ANP, and BNP induced by Ang II were restored by oral pretreatment of this high-luteolin diet. In cultured rat cardiac fibroblasts, H2O2-induced TGFβ1 expression and the phosphorylation of JNK were suppressed by luteolin pretreatment. In conclusion, food-derived luteolin has protective actions against Ang II-induced cardiac remodeling, which could be mediated through attenuation of oxidative stress.

AIM: In an insulin-resistant state, excess lipids may accumulate in various non-adipose tissues, leading to histological and functional damage. It has been suggested that peroxisome proliferator-activated receptor-gamma (PPARγ) may ameliorate disorganized lipid balance. In the current study, we analyzed whether pioglitazone, an agonist of PPARγ, reduces angiotensin II-induced vascular lipid accumulation. METHODS: Angiotensin II was infused into rats at doses of 0.7 mg/kg/day via a subcutaneously implanted osmotic minipump for 7 consecutive days. Pioglitazone was orally given at a dose of 2.5 mg/kg/day for 7 days. RESULTS: Pioglitazone significantly reduced angiotensin II-induced enhanced lipid deposition and superoxide production in the adventitia of the aorta, as detected by oil red O and dihydroethidium (DHE) staining, respectively. Increased DHE signals, some observed at the site of lipid deposition, were mainly localized in ED-1-positive monocytes/macrophages. Angiotensin II-induced upregulation of the expression of LDL receptor and Nox1 was inhibited by pioglitazone treatment. In addition, angiotensin II significantly reduced the expression of PCSK9, and this reduction was ameliorated by pioglitazone. On the other hand, pioglitazone did not significantly alter the expression of the phosphorylated forms of AMPKα and ACC, which was downregulated by angiotensin II. CONCLUSIONS: Pioglitazone treatment suppressed excess lipid accumulation and superoxide production in the aorta in an angiotensin II-induced rat model of hypertension.

Medical research including cardiovascular research aims to understand the mechanisms underlying physiology and pathophysiology. Many diseases, however, develop as a result of very complicated interactions among cells/molecules, and, therefore, no factor can be singled out as the dominant mechanism. This is even more clearly the case with chronic diseases, whose underlying mechanisms may be chronic inflammation, and insights into system links such as intercellular or inter-organ ones are, therefore, indispensable to understand the diseases. Here, I introduce heterocellular and organ-organ interplays which have critical roles in the development of cardiovascular and metabolic diseases. It is also noteworthy that a large amount of medical information is processed in daily medical practice. Additionally, numerous clinical trials, physician-led clinical research, and epidemiological studies are conducted using the Internet. Moreover, in basic research, analytical technologies to assess the functions of the genome, molecules, and cells have advanced progressively, and a large amount of information is generated in a short period of time. Large-volume information and networking are important issues among medical organizations in community medicine. In the medical practice of cardiology, covering both acute treatment and chronic disorders, it is also necessary to reconsider the flow of medical information. In particular, for future clinical practice and studies in cardiology, we need to acknowledge the risk that accompanies building up knowledge based on this large-volume information and take measures against this risk.

The intestinal epithelium maintains homeostasis by a self-renewal process involving resident stem cells, including Lgr5(+) crypt-base columnar cells, but core mechanisms and their contributions to intestinal cancer are not fully defined. In this study, we examined a hypothesized role for KLF5, a zinc-finger transcription factor that is critical to maintain the integrity of embryonic and induced pluripotent stem cells, in intestinal stem-cell integrity and cancer in the mouse. Klf5 was indispensable for the integrity and oncogenic transformation of intestinal stem cells. In mice, inducible deletion of Klf5 in Lgr5(+) stem cells suppressed their proliferation and survival in a manner associated with nuclear localization of β-catenin (Catnb), generating abnormal apoptotic cells in intestinal crypts. Moreover, production of lethal adenomas and carcinomas by specific expression of an oncogenic mutant of β-catenin in Lgr5(+) stem cells was suppressed completely by Klf5 deletion in the same cells. Given that activation of the Wnt/β-catenin pathway is the most frequently altered pathway in human colorectal cancer, our results argue that KLF5 acts as a fundamental core regulator of intestinal oncogenesis at the stem-cell level, and they suggest KLF5 targeting as a rational strategy to eradicate stem-like cells in colorectal cancer.

We conducted a retrospective study of 60 patients with ischemic heart disease (31 with diabetes and 29 without diabetes) to investigate the impact of diabetes on diurnal body temperature patterns. We found that the increase of axillary body temperature in the evening was reduced in the presence of diabetes, which was associated with autonomic neuropathy.

INTRODUCTION: Results from the multicenter trial (J-Land study) of landiolol versus digoxin in atrial fibrillation (AF) and atrial flutter (AFL) patients with left ventricular (LV) dysfunction revealed that landiolol was more effective for controlling rapid HR than digoxin. The subgroup analysis for patient characteristics was conducted to evaluate the impact on the efficacy and safety of landiolol compared with digoxin. METHODS: Two hundred patients with AF/AFL, heart rate (HR) ≥ 120 beats/min, and LV ejection fraction (LVEF) 25-50% were randomized to receive either landiolol (n = 93) or digoxin (n = 107). Successful HR control was defined as ≥20% reduction in HR together with HR < 110 beats/min at 2 h after starting intravenous administration of landiolol or digoxin. The subgroup analysis for patient characteristics was to evaluate the impact on the effectiveness of landiolol in AF/AFL patients complicated with LV dysfunction. RESULTS: The efficacy in patients with NYHA class III/NYHA class IV was 52.3%/35.3% in landiolol, and 13.8%/9.1% in digoxin (p < 0.001 and p = 0.172), lower LVEF (25-35%)/higher LVEF (35-50%) was 45.7%/51.1% in landiolol, and 14.0%/12.7% in digoxin (p < 0.001 and p < 0.001), CKD stage 1 (90 < eGFR)/CKD stage 2 (60 ≤ eGFR < 90)/CKD stage 3 (30 ≤ eGFR < 60)/CKD stage 4 (15 ≤ eGFR < 30) was 66.7%/59.1%/39.6%/66.7% in landiolol, and 0%/13.8%/17.0%/0% in digoxin (p = 0.003, p < 0.001, p = 0.015 and p = 0.040). CONCLUSIONS: This subgroup analysis indicated that landiolol was more useful, regardless of patient characteristics, as compared with digoxin in AF/AFL patients complicated with LV dysfunction. Particularly, in patients with impaired renal function, landiolol should be preferred for the purpose of acute rate control of AF/AFL tachycardia.

BACKGROUND: Animal studies have shown that shear deformation of myocardial sheets in transmural planes of left ventricular (LV) wall is an important mechanism for systolic wall thickening, and normal and shear strains of the LV free wall differ from those of the interventricular septum (IVS). We sought to test whether these also hold for human hearts. METHODS: Thirty healthy volunteers (male 23 and female 7, aged 34 ± 6 years) from Outpatient Department of the University of Tokyo Hospital were included. Echocardiographic images were obtained in the left decubitus position using a commercially available system (Aloka SSD-6500, Japan) equipped with a 3.5-MHz transducer. The ECG was recorded simultaneously. The peak systolic radial normal strain (length change), shear strain (angle change) and time to peak systolic radial normal strain were obtained non-invasively by two-dimensional speckle tracking echocardiography. RESULTS: The peak systolic radial normal strain in both IVS and LV posterior wall (LVPW) showed a trend to increase progressively from the apical level to the basal level, especially at short axis views, and the peak systolic radial normal strain of LVPW was significantly greater than that of IVS at all three levels. The time to peak systolic radial normal strain was the shortest at the basal IVS, and increased progressively from the base to the apical IVS. It gradually increased from the apical to the basal LVPW in sequence, especially at short axis views. The peak of radial normal strain of LVPW occurred much later than the peak of IVS at all three levels. For IVS, the shear deformation was clockwise at basal level, and counterclockwise at mid and apical levels in LV long-axis view. For LVPW, the shear deformations were all counterclockwise in LV long-axis view and increased slightly from base to the apex. LVPW showed larger shear strains than IVS at all three levels. Bland-Altman analysis shows very good agreement between measurements taken by the same observer and by two independent observers. CONCLUSION: "Myocardial sheets" theory also holds true for intact human LV. Moreover, dyssynchrony exists even in healthy human subjects, which should be considered when evaluating the diseased hearts.