Yoichiro Otaki

Dr. Yoichiro Otaki

Yamagata University

Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 March 2022 in Circulation
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Journal Article
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MHMakoto Hibino
Makoto Hibino
YOYoichiro Otaki
Yoichiro Otaki
EKElsa Kobeissi
Elsa Kobeissi
HPHan Pan
Han Pan
HHHiromi Hibino
Hiromi Hibino
DADagfinn Aune
Dagfinn Aune
Background: Hypertension or elevated blood pressure (BP) is an important risk factor for aortic dissection (AD); however, few prospective studies on this topic have been published. We investigated the association between hypertension/elevated BP and AD in 2 cohorts and conducted a meta-analysis of published prospective studies, including these 2 studies. Methods: We analyzed data from the J-SHC study (Japan-Specific Health Checkups) and UK Biobank, which prospectively followed up 534 378 and 502 424 participants, respectively. Multivariable Cox regression was used to estimate hazard ratios and 95% CIs for the association of hypertension/elevated BP with AD incidence in the UK Biobank and AD mortality in the J-SHC Study. In the meta-analysis, summary relative risks were calculated with random-effects models. A potential nonlinear dose-response relationship between BP and AD was tested with fractional polynomial models, and the best-fitting second-order fractional polynomial regression model was determined. Results: In the J-SHC study and UK Biobank, there were 84 and 182 ADs during the 4- and 9-year follow-up, and the adjusted hazard ratios of AD were 3.57 (95% CI, 2.17–6.11) and 2.68 (95% CI, 1.78–4.04) in hypertensive individuals, 1.33 (95% CI, 1.05–1.68) and 1.27 (95% CI, 1.11–1.48) per 20–mm Hg increase in systolic BP (SBP), and 1.67 (95% CI, 1.40–2.00) and 1.66 (95% CI, 1.46–1.89) per 10-mm Hg increase in diastolic BP (DBP), respectively. In the meta-analysis, the summary relative risks were 3.07 (95% CI, 2.15–4.38, I 2 =76.7%, n=7 studies, 2818 ADs, 4 563 501 participants) for hypertension and 1.39 (95% CI, 1.16–1.66, I 2 =47.7%, n=3) and 1.79 (95% CI: 1.51–2.12, I 2 = 57.0%, n=3) per 20–mm Hg increase in SBP and per 10–mm Hg increase in DBP, respectively. The AD risk showed a strong, positive dose-response relationship with SBP and even more so with DBP. The risk of AD in the nonlinear dose-response analysis was significant at SBP >132 mm Hg and DBP >75 mm Hg. Conclusions: Hypertension and elevated SBP and DBP are associated with a high risk of AD. The risk of AD was positively dose dependent, even within the normal BP range. These findings provide further evidence for the optimization of BP to prevent AD.

23 April 2014 in Cardiovascular Diabetology
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TNTaro Narumi
Taro Narumi
TWTetsu Watanabe
Tetsu Watanabe
SKShinpei Kadowaki
Shinpei Kadowaki
DKDaisuke Kinoshita
Daisuke Kinoshita
MYMiyuki Yokoyama
Miyuki Yokoyama
IKIsao Kubota
Isao Kubota
Various adipokines are reported to be associated with the development of heart failure (HF) through insulin resistance and chronic inflammation. Omentin-1 is a novel adipokine and is associated with incident coronary artery disease. However, it remains unclear whether serum omentin-1 levels are associated with cardiac prognosis in patients with HF. We measured serum omentin-1 levels at admission in 136 consecutive patients with HF, and 20 control subjects without signs of significant heart disease. We prospectively followed patients with HF to endpoints of cardiac death or re-hospitalization for worsening HF. Serum omentin-1 levels were markedly lower in HF patients with cardiac events compared with to without. The patients who were in New York Heart Association (NYHA) functional class IV showed significantly lower serum omentin-1 levels compared to those in class II and III, whereas serum omentin-1 levels did not correlate with serum brain natriuretic peptide levels (r = 0.217, P = 0.011). We divided the HF patients into three groups based on the tertiles of serum omentin-1 level (low T1, middle T2, and high T3). Multivariate Cox hazard analysis showed that the lowest serum omentin-1 level (T1) was independently associated with cardiac events after adjustment for confounding factors (hazard ratio 5.78, 95% confidence interval 1.20-12.79). We divided the HF patients into two groups according to the median serum omentin-1 levels. Kaplan-Meier analysis revealed that the patients with low serum omentin-1 levels had a higher risk of cardiac events compared with those with high serum omentin-1 levels (log-rank test p < 0.001). Decreased serum omentin-1 levels were associated with a poor cardiac outcome in patients with HF.

1 December 2020 in Hypertension
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Journal Article
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JGJun Goto
Jun Goto
YOYoichiro Otaki
Yoichiro Otaki
TWTetsu Watanabe
Tetsu Watanabe
YKYuta Kobayashi
Yuta Kobayashi
TATomonori Aono
Tomonori Aono
MWMasafumi Watanabe
Masafumi Watanabe
The HECT (homologous to the E6-AP carboxyl terminus)-type ubiquitin E3 ligase ITCH is an enzyme that plays an important role in ubiquitin-proteasomal protein degradation. Disheveled proteins (Dvl1 [disheveled protein 1], Dvl2, and Dvl3) are the main components of the Wnt/β-catenin signaling pathway, which is involved in cardiac hypertrophy. The aim of this study was to examine the role of ITCH during development of cardiac hypertrophy. Thoracic transverse aortic constriction (TAC) was performed in transgenic mice with cardiac-specific overexpression of ITCH (ITCH-Tg) and wild-type mice. Cardiac hypertrophy after TAC was attenuated in ITCH-Tg mice, and the survival rate was higher for ITCH-Tg mice than for wild-type mice. Protein interaction between ITCH and Dvls was confirmed with immunoprecipitation in vivo and in vitro. Expression of key molecules of the Wnt/β-catenin signaling pathway (Dvl1, Dvl2, GSK3β [glycogen synthase kinase 3β], and β-catenin) was inhibited in ITCH-Tg mice compared with wild-type mice. Notably, the ubiquitination level of Dvl proteins increased in ITCH-Tg mice. Protein and mRNA expression levels of ITCH increased in response to Wnt3a stimulation in neonatal rat cardiomyocytes. Knockdown of ITCH using small-interfering RNA increased cardiomyocyte size and augmented protein expression levels of Dvl proteins, phospho-GSK3β, and β-catenin after Wnt3a stimulation in cardiomyocytes. Conversely, overexpression of ITCH attenuated cardiomyocyte hypertrophy and decreased protein expression levels of Dvl proteins, phospho-GSK3β and β-catenin. In conclusion, ITCH targets Dvl proteins for ubiquitin-proteasome degradation in cardiomyocytes and attenuates cardiac hypertrophy by suppressing the Wnt/β-catenin signaling pathway.

Verified
Journal Article
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JGJun Goto
Jun Goto
YOYoichiro Otaki
Yoichiro Otaki
TWTetsu Watanabe
Tetsu Watanabe
MWMasafumi Watanabe
Masafumi Watanabe
Despite advances in medicine, cardiac disease remains an increasing health problem associated with a high mortality rate. Maladaptive cardiac remodeling, such as cardiac hypertrophy and fibrosis, is a risk factor for heart failure; therefore, it is critical to identify new therapeutic targets. Failing heart is reported to be associated with hyper-ubiquitylation and impairment of the ubiquitin–proteasome system, indicating an importance of ubiquitylation in the development of cardiac disease. Ubiquitylation is a post-translational modification that plays a pivotal role in protein function and degradation. In 1995, homologous to E6AP C-terminus (HECT) type E3 ligases were discovered. E3 ligases are key enzymes in ubiquitylation and are classified into three families: really interesting new genes (RING), HECT, and RING-between-RINGs (RBRs). Moreover, 28 HECT-type E3 ligases have been identified in human beings. It is well conserved in evolution and is characterized by the direct attachment of ubiquitin to substrates. HECT-type E3 ligase is reported to be involved in a wide range of human diseases and health. The role of HECT-type E3 ligases in the development of cardiac diseases has been uncovered in the last decade. There are only a few review articles summarizing recent advancements regarding HECT-type E3 ligase in the field of cardiac disease. This study focused on cardiac remodeling and described the role of HECT-type E3 ligases in the development of cardiac disease. Moreover, this study revealed that the current knowledge could be exploited for the development of new clinical therapies.

7 June 2023 in Hypertension Research
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TKTasuku Kurokawa
Tasuku Kurokawa
YOYoichiro Otaki
Yoichiro Otaki
HTHiroki Takahashi
Hiroki Takahashi
TWTetsu Watanabe
Tetsu Watanabe
TSTaku Shikama
Taku Shikama
MWMasafumi Watanabe
Masafumi Watanabe

26 November 2021 in Journal of Clinical Medicine
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Journal Article
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KWKen Watanabe
Ken Watanabe
TWTetsu Watanabe
Tetsu Watanabe
YOYoichiro Otaki
Yoichiro Otaki
TMTakayo Murase
Takayo Murase
TNTakashi Nakamura
Takashi Nakamura
MWMasafumi Watanabe
Masafumi Watanabe
Xanthine oxidoreductase (XOR) is the rate-limiting enzyme in uric acid (UA) production that plays a pivotal role in generating oxidative stress. Gender differences in the impact of plasma XOR activity on coronary artery spasm (CAS) remain unclear. We investigated plasma XOR activity in 132 patients suspected of having CAS (male, n = 78; female, n = 54) and who underwent an intracoronary acetylcholine provocation test. Plasma XOR activity was significantly lower in female patients compared with male patients. CAS was provoked in 36 male patients and 17 female patients, and both had significantly higher plasma XOR activity than those without. Multivariate logistic regression analysis showed that this activity was independently associated with the incidence of CAS in both sexes after adjusting for confounding factors. The optimal cut-off values for predicting CAS were lower in female patients than in male patients. Multivariate analysis demonstrated that female patients with high XOR activity exhibited a higher incidence of CAS than male patients. Plasma XOR activity was an independent predictor of the incidence of CAS in both sexes. The impact of plasma XOR activity on CAS was stronger in female patients than in male patients.