Publications by authors named "Seiko Koizumi"

Objective: The various functionalities of collagen peptides have generated a large interest in utilizing the bioactive peptides as a nutritional therapy to ameliorate various physiological degenerative conditions. Collagen peptides are observed to reduce the pain and aligned difficulties with respect to osteoarthritis. Here we report the enhanced ameliorating property of novel high-functional "Wellnex" Type J collagen peptides following a double-blind randomized active and placebo-controlled 5-arm clinical trial ( = 100) by using it as a nutritional supplement in subjects with knee joint osteoarthritis in comparison with conventional bovine collagen peptides.

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In this randomized, double-blind, placebo-controlled study, we investigated the effects of collagen peptides (CP) containing high concentrations of prolyl-hydroxyproline and hydroxyprolyl-glycine on advanced glycation end products (AGEs) levels in the skin and subcutaneous blood vessel walls. A total of 31 individuals aged 47-87 years were randomly assigned to receive either 5 g/day of fish-derived CP or a placebo for 12 weeks. Body and blood compositions and AGEs levels were measured at the beginning and end of the study.

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Oral ingestion of collagen hydrolysate has various benecial effects. We developed a novel fermented collagen peptide (FCP), different from the conventional collagen peptides, by fermenting gelatin with Aspergillus sojae. This study aimed to investigate the effect of FCP in inhibiting fat accumulation under high-fat loading.

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Introduction: We examined the effect of 5.0 g/day of collagen peptide (CP) or collagen peptide fermented with Aspergillus sojae (FCP) on skin pigmentation in healthy participants.

Methods: In this randomized, double-blind, placebo-controlled study, 44 men and women aged 25-63 years were placed into three groups by stratified random allocation and treated with CP, FCP, or placebo (PL) at 5.

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Hypertrophic scars found on the human body rarely develop in experimental animals, possibly due to their looser skin structure. This makes it difficult to understand the genesis of scar lesions. Therefore, appropriate animal models are urgently needed.

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Collagens act as cellular scaffolds in extracellular matrixes, and their breakdown products may also have important biological functions. We hypothesize that collagen dipeptide Pro-Hyp induces favorable healing activities and examined the effects of Pro-Hyp administered via different routes on wound healing using our novel murine model, in which an advanced fibrosis-prone scar lesion was developed in the abdominal muscle wall under the skin. After excising a part of the abdominal wall, a free-drinking experiment was performed using solutions with casein (CS), high molecular weight collagen peptides (HP), and low molecular weight collagen peptides including Pro-Hyp and Hyp-Gly (LP), in addition to water (HO).

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Active collagen oligopeptides (ACOP) are bioactive collagen-derived peptides detected by a recently-established ELISA. To facilitate studies of the function and metabolism of these products, this study aims to determine which of these peptides is recognized by a novel anti-ACOP antibody used in this ELISA. We then investigate the effect of collagen peptide (CP) ingestion and exercise on urinary ACOP concentrations in a cohort of university student athletes using colorimetric, LC-MS/MS, and ELISA.

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This study investigated the effects of collagen hydrolysates (CH) on language cognitive function and brain structure. In this open-label study, 5 g CH was administered once a day for 4 weeks to 30 healthy participants aged 49-63 years. The primary outcome measures were the brain healthcare quotients based on gray matter volume (GM-BHQ) and fractional anisotropy (FA-BHQ).

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The aim of this study was to evaluate the antidiabetic properties of collagen hydrolysates (CHs). CHs exhibited dipeptidyl peptidase-IV inhibitory activity and stimulated glucagon-like-peptide-1 (GLP-1) secretion in vitro. We also determined whether CHs improve glucose tolerance in normal mice.

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Article Synopsis
  • The study investigates how warm ischemia affects gene expression in tissue samples from lung, liver, kidney, and spleen in rats, using cDNA array analysis and other techniques.
  • Despite no visible changes in RNA quality, the cDNA array revealed significant modulation of gene expression due to warm ischemia, with variation in percentage among different tissues (e.g., 19.1% in lung).
  • The research highlights that warm ischemia can lead to a differential transcriptional response in tissues and indicates that surgical tissue samples may carry the effects of ischemia, which should be considered in genetic analyses.
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