Yasuhide Kuwabara

Learn More
BACKGROUND Recently, elevation of circulating muscle-specific microRNA (miRNA) levels has been reported in patients with acute myocardial infarction. However, it is still unclear from which part of the myocardium or under what conditions miRNAs are released into circulating blood. The purpose of this study was to identify the source of elevated levels of(More)
GLUT4 shows decreased levels in failing human adult hearts. We speculated that GLUT4 expression in cardiac muscle may be fine-tuned by microRNAs. Forced expression of miR-133 decreased GLUT4 expression and reduced insulin-mediated glucose uptake in cardiomyocytes. A computational miRNA target prediction algorithm showed that KLF15 is one of the targets of(More)
Retrovirus insertion-mediated random mutagenesis was applied in 3T3-L1 preadipocyte cells to better understand the molecular basis of obesity (the expansion of individual adipocytes). We found that tryptophan hydroxylase-1, a rate-limiting enzyme for the synthesis of serotonin (5-HT), is expressed in adipocytes and is required for their differentiation. A(More)
Sterol regulatory element-binding protein 2 (SREBP-2) transcription factor has been identified as a key protein in cholesterol metabolism through the transactivation of the LDL receptor and cholesterol biosynthesis genes. Here, we generated mice lacking microRNA (miR)-33, encoded by an intron of the Srebp2, and showed that miR-33 repressed the expression of(More)
BACKGROUND Cholesterol efflux from cells to apolipoprotein A-I (apoA-I) acceptors via the ATP-binding cassette transporters ABCA1 and ABCG1 is thought to be central in the antiatherogenic mechanism. MicroRNA (miR)-33 is known to target ABCA1 and ABCG1 in vivo. METHODS AND RESULTS We assessed the impact of the genetic loss of miR-33 in a mouse model of(More)
MicroRNAs (miRNAs), small noncoding RNAs, are negative regulators of gene expression and play important roles in gene regulation in the heart. To examine the role of miRNAs in the expression of the two isoforms of the cardiac myosin heavy chain (MHC) gene, α- and β-MHC, which regulate cardiac contractility, endogenous miRNAs were downregulated in neonatal(More)
RATIONALE In some patients with type 2 diabetes mellitus (DM) without hypertension, cardiac hypertrophy and attenuated cardiac function are observed, and this insult is termed diabetic cardiomyopathy. To date, microRNA (miRNAs or miR) functions in diabetic cardiomyopathy remain to be elucidated. OBJECTIVE To clarify the functions of miRNAs involved in(More)
MicroRNAs (miRNAs) are a class of small noncoding RNAs that have gained status as important regulators of gene expression. Recent studies have demonstrated that miRNAs are aberrantly expressed in the cardiovascular system under some pathological conditions. Gain- and loss-of-function studies using in vitro and in vivo models have revealed distinct roles for(More)
Microglia are well known to become activated during various kinds of neuropathological events. The factors that are responsible for the activation, however, are not fully determined. In the present study, L-Ser was shown to enhance production of nitric oxide (NO), interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF alpha) by lipopolysaccharide(More)
MicroRNAs (miRNAs or miRs) are small, non-coding RNAs that modulate mRNA stability and post-transcriptional translation. A growing body of evidence indicates that specific miRNAs can affect the cellular function of cardiomyocytes. In the present study, miRNAs that are highly expressed in the heart were overexpressed in neonatal rat ventricular myocytes, and(More)