Publications by authors named "Ikuko Miyagi"

Inhibition of poly(ADP-ribose) polymerase 1 (PARP1) is one of the most promising strategies for cancer chemotherapy, and a number of inhibitors possessing nicotinamide-like structures are being developed. To discover new types of PARP1 inhibitors, we screened a large number of substances of plant origin and isolated two inhibitory substances from the leaves of Syzygium samarangense (Blume) Merrill & L.M.

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Silicon is rich in the normal human aorta but decreases with age and the development of atherosclerosis. We hypothesized that soluble silica (Si) and coral sand (CS), as a natural Si-containing material, would suppress high blood pressure (BP) in spontaneously hypertensive rats (SHRs), and clarify the observed antihypertensive mechanism by cell cultures by quantifying messenger RNA expressions in the aorta. In SHR fed diets containing 1% Ca supplemented with CaCO(3) as the control (CT) and CS in a Ca-deficient diet and containing 50 mg/kg Si in the CT diet for 8 weeks, systolic BP was significantly (P < .

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Objective: In our previous study to evaluate the effects of soluble silicon (Si) on bone metabolism, Si and coral sand (CS) as a natural Si-containing material suppressed peroxisome proliferator-activated receptor γ (PPARγ), which regulates both glucose and bone metabolism and increases adipogenesis at the expense of osteogenesis, leading to bone loss. In this study, we investigated the anti-diabetic effects of bone-seeking elements, Si and stable strontium (Sr), and CS as a natural material containing these elements using obese diabetic KKAy mice.

Methods: Weanling male mice were fed diets containing 1% Ca supplemented with CaCO(3) as the control and CS, and diets supplemented with 50 ppm Si or 750 ppm Sr to control diet for 56 d.

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The cyclopentenonic prostaglandin 15-deoxy-Delta(12,14)-PG J(2) (15d-PGJ(2)) is a metabolite derived from PGD(2). Although 15d-PGJ(2) has been demonstrated to be a potent ligand for peroxisome proliferator activated receptor gamma (PPARgamma), the functions are not fully understood. In order to examine the effect of 15d-PGJ(2) on histone acetyltransferases (HATs), several lines of cell including mouse embryonic fibroblast (MEF) cells were exposed to 15d-PGJ(2).

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Objective: The effects of five calcium (Ca) sources were compared for bone biochemical and mechanical properties and the related gene expression using mice, from the viewpoint of their soluble silicon (Si) content.

Methods: Weanling male mice were fed diets containing 1% Ca supplemented with CaCO(3) as the control (CT), coral sand (CS), fossil stony coral (FSC), fish bone (FC) and eggshell (EC) powders, and 50 ppm of Si in the CT diet for 6 mo. The mRNA expressions related to bone remodeling were quantified by real-time polymerase chain reaction.

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Silicon has been known as an essential element for bone formation. The silicon contents of sea water increase with increasing of depth: 1.8 ppm Si in deep-sea water (DW) at 612 m in depth versus 0.

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Fibrinogen is a large plasma glycoprotein with a molecular mass of 340kDa that plays a critical role in the final stage of blood coagulation. Human plasma fibrinogen is a dimeric molecule comprising two sets of three different polypeptides (Aalpha, 66kDa; Bbeta, 55kDa; gamma, 48kDa). To express recombinant human fibrinogen in the methylotrophic yeast Pichia pastoris, we constructed an expression vector containing three individual fibrinogen chain cDNAs under the control of the mutated AOX2 (mAOX2) promoter.

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Background: We reported a reciprocal relationship between reduced serum selenium (Se) and elevated serum C-reactive protein (CRP) in various pathological conditions in comparison with the levels in 141 healthy subjects. To clarify the implications of these observations, the effect of Se on nuclear factor (NF)-kappaB, which upregulates the CRP synthesis in the liver, was examined.

Methods: Human hepatoma cell line HuH-7 was cultured in medium with 2% fetal calf serum (FCS) for 3 days for the Se deprivation, followed by another 3 days in the same medium containing sodium selenite prior to stimulation of the cells with either monocyte-conditioned medium (MoCM) or tumor necrosis factor-alpha (TNF-alpha).

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Background: Selenium (Se), an essential trace element, is known to be a cofactor of antioxidative selenoenzymes such as glutathione peroxidase and thioredoxin reductase.

Methods: We assessed the pathophysiological significance of selenium (Se) by comparing the concentrations of serum Se and C-reactive protein (CRP) in healthy subjects (141; M=71, F=70) vs. patients with various pathological conditions.

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