Publications by authors named "Toshiaki Suguro"

Salusin-alpha was recently shown to exert anti-atherosclerotic effects and its potential role as a clinical marker for atherosclerosis has been proposed. We determined serum salusin-alpha concentrations in 99 patients across a diverse range of renal functions and urinary salusin-alpha excretions in 12 patients with non-dialyzed renal failure using a highly sensitive and specific radioimmunoassay. Serum salusin-alpha concentrations in patients with moderate to advanced renal insufficiency (eGFR < 30 ml/min/1.

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Aim: Human urotensin-II (UII) is a cyclic neuropeptide with potent vasoconstrictive activity in the vasculature. The expression of UII and its receptor (UT) mRNA is detected at high levels in the brain. We evaluated the relationship between plasma UII levels and vascular dementia (VaD) caused by stroke or atherosclerotic small vessel disease.

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Human urotensin II (U-II), the most potent vasoconstrictor undecapeptide identified to date, and its receptor (UT) are involved in the pathogenesis of systemic and pulmonary hypertension. Here, we review recent advances in our understanding of the pathophysiology of U-II with particular reference to its role in atherosclerotic cardiovascular diseases. Single-nucleotide polymorphisms of U-II gene (S89N) are associated with onset of essential hypertension, type II diabetes mellitus, and insulin resistance in the Asian population.

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Objective: Our recent studies have indicated that urotensin II, the most potent vasoconstrictor peptide identified to date, potentiates human macrophage foam cell formation and vascular smooth muscle cell proliferation, and its levels are increased in the plasma of hypertensive patients with carotid atherosclerotic plaques. In the present study, we investigated the enhancing effect of urotensin II on atherosclerosis in apolipoprotein E-knockout mice and its suppression by 4-aminoquinoline, an urotensin II receptor-selective antagonist.

Methods: Urotensin II, urotensin II + 4-aminoquinoline, or vehicle was infused for 4 weeks through an osmotic mini-pump into 9-week-old apolipoprotein E-knockout mice on a high-fat diet.

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Salusin-alpha is a new bioactive peptide with mild hypotensive and bradycardic effects. Our recent study showed that salusin-alpha suppresses foam cell formation in human monocyte-derived macrophages by down-regulating acyl-CoA:cholesterol acyltransferase-1, contributing to its anti-atherosclerotic effect. To clarify the clinical implications of salusin-alpha in hypertension and its complications, we examined the relationship between serum salusin-alpha levels and carotid atherosclerosis in hypertensive patients.

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Human U-II (urotensin-II), the most potent vasoconstrictor peptide identified to date, is associated with cardiovascular disease. A single nucleotide polymorphism (S89N) in the gene encoding U-II (UTS2) is associated with the onset of Type 2 diabetes and insulin resistance in the Japanese population. In the present study, we have demonstrated a relationship between plasma U-II levels and the progression of diabetic retinopathy and vascular complications in patients with Type 2 diabetes.

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Background: Circulating blood levels of human urotensin II (U-II), the most potent vasoconstrictor peptide identified to date, are increased in patients with essential hypertension. Our previous studies showed that U-II accelerates human macrophage foam cell formation and vascular smooth muscle cell proliferation, suggesting development of atherosclerotic plaque. In this study, we demonstrated a correlation between plasma U-II level and progression of atherosclerosis in hypertensive patients.

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Small dense low-density lipoprotein (sd LDL) is more atherogenic than large buoyant (lb) LDL, which is relatively high in particle number (as estimated by apolipoprotein [apo] B) and poor in cholesterol (C) content. Because recent epidemiological studies have shown that serum apo B is a stronger predictor of the risk of coronary heart disease (CHD) than LDL-C, we assumed that this strong predictive power of apo B for CHD is attributable to a close association with sd LDL concentration. On the other hand, non-HDL-C has been proposed as an integrated CHD risk marker containing all atherogenic apo B-containing lipoproteins.

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Human urotensin II (U-II), the most potent vasoconstrictor peptide identified to date, and its receptor (UT) are involved in hypertension and atherosclerosis. Acyl-coenzyme A:cholesterol acyltransferase-1 (ACAT-1) converts intracellular free cholesterol into cholesterol ester (CE) for storage in lipid droplets and plays an important role in the formation of macrophage-derived foam cells in atherosclerotic lesions. We examined the effects of U-II on ACAT-1 expression and CE accumulation in human monocyte-derived macrophages.

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Acyl-coenzyme A:cholesterol acyltransferase-1 (ACAT-1) converts intracellular free cholesterol into cholesterol ester for storage in lipid droplets and plays an important role in the formation of macrophage-derived foam cells in atherosclerotic lesions. Serotonin (5-HT), a potent vasoconstrictor that is released from activated platelets, increases uptake of oxidized low-density lipoprotein (LDL) by macrophages, leading to foam cell formation, and contributes to the development of atherosclerotic plaque. However, it is not yet known whether 5-HT affects ACAT-1 expression in human monocyte-macrophages as the molecular mechanism of enhanced foam cell formation by 5-HT remains unclear.

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