Publications by authors named "Akiyoshi Suganuma"

Vitamin A deficiency (VAD) caused by malnutrition and certain intestinal diseases induces visual impairments, including night blindness and photoreceptor cell dysfunction as indicated by reduced a‑ and b‑waves in an electroretinogram (ERG). The effects of VAD on the inner retinal layer cells, including amacrine and ganglion cells, remain to be elucidated. The functions of these cells are reflected in oscillatory potentials (OPs), another component of the ERG.

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Article Synopsis
  • - E2012, a gamma secretase modulator aimed at treating Alzheimer's by reducing amyloid β-42, caused cataracts in rats after repeated doses, first appearing as opacity in the lens around weeks 10-11.
  • - The cataract development was linked to increased levels of lenticular desmosterol (a cholesterol precursor) and decreased cholesterol, suggesting that E2012 inhibits a key enzyme (DHCR24) involved in cholesterol biosynthesis.
  • - The study implies that changes in desmosterol levels could serve as a safety biomarker for predicting cataract formation, as these changes were identified in the lens, liver, and plasma before visible cataract development in the lens.
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Previously, we reported that the mutation frequency was markedly increased in the colon after the oral treatment of mice with an environmental mutagen/carcinogen, benzo[a]pyrene (BP); however this was not followed by tumor development. The reasons for this are as yet unresolved. The purpose of the present study is to explore the mechanisms why a high frequency of mutations induced by BP in the colon is not associated with subsequent tumor development.

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This (1)H nuclear magnetic resonance metabonomics study was aimed to determine urinary biomarkers of cholestasis resulting from inhibition of biliary secretion of bile or obstruction of bile flow. To inhibit biliary secretion of bile, cyclosporine A was administered to male Sprague-Dawley rats. Obstruction of bile flow was induced by administration of 4,4'-methylene dianiline, alpha-naphthylisothiocyanate or bile duct ligation.

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Egasyn-beta-glucuronidase complex is located at the luminal site of liver microsomal endoplasmic reticulum. When organophosphorus insecticides (OP) are incorporated into the liver microsomes, they become tightly bound to egasyn, a carboxylesterase isozyme, and subsequently, beta-glucuronidase (BG) is dissociated and released into blood. Consequently, the increase in plasma BG activity becomes a good biomarker of OP exposure.

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