Respiration in adipocytes is inhibited by reactive oxygen species.

It is a desirable goal to stimulate fuel oxidation in adipocytes and shift the balance toward less fuel storage and more burning. To understand this regulatory process, respiration was measured in primary rat adipocytes, mitochondria, and fat-fed mice. Maximum O(2) consumption, in vitro, was determined with a chemical uncoupler of oxidative phosphorylation (carbonylcyanide p-trifluoromethoxyphenylhydrazone (FCCP)).

Beneficial response to macrolide antibiotic in a patient with desquamative interstitial pneumonia refractory to corticosteroid therapy.

Macrolide antibiotics have been shown to have a beneficial effect in a number of pulmonary conditions that are characterized by inflammation, including cystic fibrosis, asthma, and cryptogenic organizing pneumonia. We report the first case of desquamative interstitial pneumonia (DIP) showing a favorable response to treatment with clarithromycin. If confirmed, this observation would add DIP to the list of pulmonary disorders that are amenable to the beneficial antiinflammatory effects of macrolides.

Differential modulation of L-type calcium channel subunits by oleate.

Nonesterified fatty acids such as oleate and palmitate acutely potentiate insulin secretion from pancreatic islets in a glucose-dependent manner. In addition, recent studies show that fatty acids elevate intracellular free Ca(2+) and increase voltage-gated Ca(2+) current in mouse beta-cells, although the mechanisms involved are poorly understood. Here we utilized a heterologous system to express subunit-defined voltage-dependent L-type Ca(2+) channels (LTCC) and demonstrate that beta-cell calcium may increase in part from an interaction between fatty acid and specific calcium channel subunits.

The L-type voltage-gated Ca2+ channel is the Ca2+ sensor protein of stimulus-secretion coupling in pancreatic beta cells.

L-type voltage-gated Ca2+ channels (Cav1.2) mediate a major part of insulin secretion from pancreatic beta-cells. Cav1.

Ca2+, NAD(P)H and membrane potential changes in pancreatic beta-cells by methyl succinate: comparison with glucose.

The present study was undertaken to determine the main metabolic secretory signals generated by the mitochondrial substrate MeS (methyl succinate) compared with glucose in mouse and rat islets and to understand the differences. Glycolysis and mitochondrial metabolism both have key roles in the stimulation of insulin secretion by glucose. Both fuels elicited comparable oscillatory patterns of Ca2+ and changes in plasma and mitochondrial membrane potential in rat islet cells and clonal pancreatic beta-cells (INS-1).