Koichiro Yasuda

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In this study, we investigated the effects of endocrine disrupters bisphenol A (BPA) and nonylphenol (NP) on insulin secretion from rat pancreatic islets. Following acute exposure to BPA and NP, neither BPA nor NP (0.1, 1, 10, 100 and 1000 microg/l) affected insulin secretion in concentrations of 16.7 mM glucose. However, insulin secretion following(More)
BACKGROUND Estrogens exert beneficial effects on the cardiovascular system that are mediated by estrogen receptors. We examined the association between the estrogen receptor alpha gene (ESR1) PvuII and XbaI polymorphisms and cardiac autonomic nervous function in Japanese males. METHODS We examined 252 young healthy males for association of ESR1 PvuII and(More)
OBJECTIVES The mitochondrial uncoupling proteins UCP2 and UCP3 are implicated in energy metabolism and regulation of reactive oxygen species, which are closely involved in autonomic nervous system function. Heart rate variability (HRV) reflects cardiac autonomic regulation and has been used to evaluate dysfunction of the autonomic nervous system in(More)
The small intestine plays an important role in the digestion and absorption of many nutrients. To investigate the contribution of carbohydrate digestion to diabetes mellitus, we examined the morphological changes of the small intestine, and the expression of sucrase-isomaltase, which is one of the intestinal disaccharidases, in diabetic model rat, that is(More)
We have reported that a change in muscle fibre type distribution is present in two strains of diabetic rats (Otsuka Long-Evans Tokushima Fatty and Goto-Kakizaki rats). In this study, we determined whether the change in soleus muscle fibre type distribution was caused by diabetes, using obese, diabetic (Zucker diabetic fatty, ZDF), obese, non-diabetic(More)
1. Dipeptidyl peptidase IV (DPP-IV) is a new drug target in the treatment of Type 2 diabetes. Dipeptidyl peptidase IV enzyme activity is significantly altered in Type 2 diabetic patients with hyperglycaemia, but the underlying molecular mechanisms remain unclear. 2. The first aim of the present study was to clarify whether glucose regulates DPP-IV enzyme(More)
1. To investigate the pharmacological effects of T-1095, this novel derivative of phlorizin was administered to GK rats for 8 weeks. T-1095 treatment significantly lowered plasma glucose and glycosylated haemoglobin (HbA1c) levels, but did not significantly affect bodyweight. 2. T-1095 treatment did not affect 3.3 mmol/L glucose-induced insulin secretion in(More)
1. Fibre type distributions of the slow soleus and fast plantaris muscles were investigated in 5-, 9- and 20-week-old male Goto-Kakizaki (GK) rats, as an animal model of non-obese diabetes, and were compared with those of age-matched non-diabetic Wistar rats. 2. Bodyweight and both soleus and plantaris muscle weights were lower in GK rats than in Wistar(More)
The effects of hyperbaric exposure with high oxygen concentration on glucose and insulin levels and skeletal muscle-fiber properties were investigated in type 2 diabetic Goto-Kakizaki rats. Five-week-old rats were exposed to a hyperbaric environment (1.25 atmospheric pressure) with a high oxygen concentration (36%) for 6 h daily. Glucose and insulin levels(More)
BACKGROUND The 52-week monotherapy with the dipeptidyl peptidase-4 inhibitor sitagliptin and the sulphonylurea glimepiride on early-phase insulin secretion in Japanese patients with type 2 diabetes mellitus (T2DM) is not known. METHODS A randomized, parallel-group, open-label trial was conducted at 18 centers between February, 2011 and March, 2013. 171(More)