BACKGROUND AND OBJECTIVES Insulin has several physiologic actions that include stimulation of cellular glucose and potassium uptake. The ability of insulin to induce glucose uptake by cells is impaired in type 2 diabetes mellitus, but whether potassium uptake is similarly impaired is not known. This study examines whether the cellular uptake of these molecules is regulated in concert or indepen...

Lymphocyte homeostasis requires coordination of metabolic processes with cellular energetic and biosynthetic demands but mechanisms that regulate T-cell metabolism are uncertain. We show that interleukin-7 (IL-7) is a key regulator of glucose uptake in T lymphocytes. To determine how IL-7 affects glucose uptake, we analyzed IL-7 signaling mechanisms and regulation of the glucose transporter, Gl...

The liver plays a major role in the regulation of glucose homoeostasis. Evidence from liver-specific insulin receptor knockout mice (LIRKO) suggested that insulin's direct and indirect effects on glucose utilization by the liver both require the presence of hepatic insulin receptors (IR). To address this issue, we have generated immortalized neonatal hepatocytes bearing (HIR LoxP) or not (HIR K...

Myostatin is a member of the transforming growth factor (TGF)-beta superfamily, known for its ability to inhibit muscle growth. It can also regulate metabolism and glucose uptake in a number of tissues. To determine the mechanism of myostatin's effect on glucose uptake, we evaluated its actions using choriocarcinoma cell lines that are widely used as models for placental cells. Protein and mRNA...

Skeletal muscle includes many individual fibers with diverse phenotypes. A barrier to understanding muscle glucose uptake at the cellular level has been the absence of a method to measure glucose uptake by single fibers from mammalian skeletal muscle. This study's primary objective was to develop a procedure to measure glucose uptake by single fibers from rat skeletal muscle. Rat epitrochlearis...

Since insulin resistance can lead to hyperglycemia, improving glucose uptake into target tissues is critical for regulating blood glucose levels. Among the free fatty acid receptor (FFAR) family of G protein-coupled receptors, GPR41 is known to be the Gαi/o-coupled receptor for short-chain fatty acids (SCFAs) such as propionic acid (C3) and valeric acid (C5). This study aimed to investigate the...

Lymphocyte homeostasis requires coordination of metabolic processes with cellular energetic and biosynthetic demands but mechanisms that regulate T-cell metabolism are uncertain. We show that interleukin-7 (IL-7) is a key regulator of glucose uptake in T lymphocytes. To determine how IL-7 affects glucose uptake, we analyzed IL-7 signaling mechanisms and regulation of the glucose transporter, Gl...

The effects of proteolytic and phospholipase AZ digestion on the transport of D-glucose by intact human erythrocytes and on the uptake of n-glucose by isolated erythrocyte membranes have been studied. This stereospecific uptake of D-glucose was previously shown to be compatible with the over-all monosaccharide transport system in erythrocytes and evidence was presented that it represented the b...

The effects of proteolytic and phospholipase AZ digestion on the transport of D-glucose by intact human erythrocytes and on the uptake of n-glucose by isolated erythrocyte membranes have been studied. This stereospecific uptake of D-glucose was previously shown to be compatible with the over-all monosaccharide transport system in erythrocytes and evidence was presented that it represented the b...

We investigated the effect of angiotensin-converting enzyme inhibitors on glucose uptake regulation as well as the effect of bradykinin (BK) on glucose uptake and its regulation by using inhibitors of phospholipase C, BK B2 receptor, protein kinase C, phosphatidylinositol 3-kinase, tyrosine kinase, and intracellular Ca(2+). We measured 2-deoxyglucose uptake by using L(6) skeletal muscle cells. ...