The mechanisms leading to weight loss in patients with chronic obstructive pulmonary disease (COPD) are poorly understood but may involve alterations in macronutrient metabolism. Changes in muscle oxidative capacity and lactate production during exercise suggest glucose metabolism may be altered in COPD subjects. The objective of this study was to determine differences in the rates of glucose p...

Amino acid-Fe(II)-chelator complexes exhibit strong antioxidant activity. Taking advantage of the unique spectral characteristics of the complexes formed when Ferrozine (Fz) is used as the chelator, we now show that the primary blue complex (epsilon(max) at 632 nm) decomposes by two independent pathways: (i) a nonoxidative pathway involving dissociation of the amino acid component and formation...

To determine whether activation by insulin of glycogen synthase (GS), phosphofructokinase (PFK), or pyruvate dehydrogenase (PDH) in skeletal muscle regulates intracellular glucose metabolism, subjects were studied basally and during euglycemic insulin infusions of 12, 30, and 240 mU/m2 X min. Glucose disposal, oxidative and nonoxidative glucose metabolism were determined. GS, PFK, and PDH were ...

Histidase catalyzes the irreversible nonoxidative deamination of histidine to urocanic acid. This reaction (Equation 1) has been studied in mammalian and bacterial preparations (1). Although enzymes which carry out similar deaminations of other amino acids (notably aspartic acid) have been described, to date no detailed studies of the mechanism of the process of nonoxidative deamination have be...

The methane to olefins, aromatics, and hydrogen (MTOAH) process via Pt/CeO2 catalysts poses an attractive route improve yield stability for the direct catalytic conversion of methane. In this study, two sets samples, one composed PtOx single sites on ceria other with additional Pt agglomerates, were prepared. Both samples showed enhanced activity exceeding performance pure ceria. Pulsed reactio...

The transition from rest to intense exercise is a challenge to cellular energetics (11, 13, 15). The metabolic fuels, i.e., the sources of ATP to sustain muscular contraction, are creatine phosphate and glycogen. Two anaerobic metabolic paths, leading to ATP generation, are catalyzed by creatine kinase and by the 12 enzymes of nonoxidative glycolysis, starting from glycogen. There is now genera...

A recently identified function of leptin is to protect nonadipose tissues from the nonoxidative metabolic products of long-chain fatty acids (FAs) during periods of overnutrition by increasing the -oxidative metabolism of surplus FAs and reducing lipogenesis. When this protective system fails, harmful products of nonoxidative metabolism such as ceramide increase in nonadipose tissues, including...

The nonoxidative pentose phosphate pathway allows glucose conversion to ribose for DNA or RNA synthesis and glucose degradation to lactate controlled by transketolase enzyme reactions. It has been postulated, that this pathway is of the utmost importance in tumors for the proliferation process. We detected a strong upregulation of the mutated transketolase transcript (TKTL1) in a considerable n...