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Ogawa, W.

Publications and source records attributed to Ogawa, W..

3 recordsLinked to original sources

A skeletal muscle-sympathetic nerve-intestine network underlies muscle inflammation and atrophy induced by immobilization

Immobility is a common cause of muscle atrophy, but the underlying mechanisms have remained unclear. Here we show that limb immobilization in mice elicits inflammation and atrophy of skeletal muscle that are preventable by neutralizing antibodies to the chemokine CXCL10. Limb immobilization also induced changes to the gut microbiota and intestinal inflammation, and either sterilization of the intestine with antibiotics or administration of 10-hydroxy-cis-12-octadecenoic acid--a linoleic acid-derived gut microbial metabolite--prevented intestinal and muscle inflammation as well as muscle atrophy induced by immobilization, implicating intestinal inflammation in muscle inflammation and atrophy. Limb immobilization activated sympathetic nerves and increased {beta}2-adrenergic receptor gene (Adrb2) expression in the intestine. Single-cell RNA-sequencing analysis revealed that, among cells expressing Adrb2 in the intestine, immobilization increased only the population of macrophages. Pharmacological inhibition or macrophage-specific ablation of Adrb2 prevented immobilization-induced intestinal and muscle inflammation. Our results thus implicate a previously unrecognized muscle-nerve-intestine network in immobilization-induced muscle atrophy.

molecular biology↗

Insulin Effectiveness, a Measure Consisting of Insulin Sensitivity, Secretion, and Clearance, Captures Differences Between Diabetic and Nondiabetic States

ContextInsulin clearance is implicated in regulation of glucose homeostasis independently of insulin sensitivity and insulin secretion. ObjectiveTo understand the relation between blood glucose and insulin sensitivity, secretion, and clearance. MethodsWe performed a hyperglycemic clamp, a hyperinsulinemic-euglycemic clamp, and an oral glucose tolerance test (OGTT) in 47, 16, and 49 subjects with normal glucose tolerance (NGT), impaired glucose tolerance (IGT), and type 2 diabetes mellitus (T2DM), respectively. Mathematical analyses were retrospectively performed on this dataset. ResultsThe disposition index (DI), defined as the product of insulin sensitivity and secretion, showed a weak correlation with blood glucose levels, especially in IGT (r = 0.04; 95% CI, -0.63- 0.44). However, an equation relating DI, insulin clearance, and blood glucose levels was well conserved regardless of the extent of glucose intolerance. As a measure of the effect of insulin, we developed an index, designated "DI/cle," that is based on this equation and corresponds to DI divided by the square of insulin clearance. DI/cle was not impaired in IGT compared with NGT, possibly as a result of a decrease in insulin clearance in response to a reduction in DI, whereas it was impaired in T2DM relative to IGT. Moreover, DI/cle estimated from a hyperinsulinemic-euglycemic clamp, OGTT, or a fasting blood test were significantly correlated with that estimated from two clamp tests (r = 0.52; 95% CI, 0.37- 0.64, r = 0.43; 95% CI, 0.24- 0.58, and r = 0.54; 95% CI, 0.38- 0.68, respectively). ConclusionsDI/cle can serve as a new indicator for the trajectory of changes in glucose tolerance.

systems biology↗

Bidirectional Changes Of Hepatic And Peripheral Insulin Clearance Characterize Abnormal Temporal Patterns Of Serum Insulin Concentration In Diabetic Subjects

Insulin plays a central role in glucose homeostasis, and impairment of insulin action causes glucose intolerance and leads to type 2 diabetes mellitus (T2DM). A decrease in the transient peak and sustained increase of circulating insulin by glucose infusion accompany T2DM pathogenesis. However, the mechanism underlying this abnormal temporal pattern of circulating insulin concentration remains unknown. Here we show that bidirectional changes of hepatic and peripheral insulin clearance characterize this abnormal temporal pattern of circulating insulin concentration during the progression of T2DM. We developed a mathematical model using a hyperglycemic and hyperinsulinemic-euglycemic clamp in 111 subjects, including healthy normoglycemic and diabetic subjects. The hepatic and peripheral insulin clearance significantly increase and decrease, respectively, during the progression of glucose intolerance. The increased hepatic insulin clearance reduces the amplitude of circulating insulin concentration, whereas the decreased peripheral insulin clearance changes the temporal patterns of circulating insulin concentration from transient to sustained. These results provide insight that may be useful in treating T2DM associated with aberrant insulin clearance.

systems biology↗