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Cooper, D.

Publications and source records attributed to Cooper, D..

3 recordsLinked to original sources

Quantitative analysis of the physiological contributions of glucose to the TCA cycle

ABSTRACTThe carbon source for catabolism in vivo is a fundamental question in metabolic physiology. Limited by data and rigorous mathematical analysis, controversy exists over the nutritional sources for carbon in the tricarboxylic acid (TCA) cycle under physiological settings. Using isotope-labeling data in vivo across several experimental conditions, we construct multiple models of central carbon metabolism and develop methods based on metabolic flux analysis (MFA) to solve for the preferences of glucose, lactate, and other nutrients used in the TCA cycle across many tissues. We show that in nearly all circumstances, glucose contributes more than lactate as a nutrient source for the TCA cycle. This conclusion is verified in different animal strains from different studies, different administrations of 13C glucose, and is extended to multiple tissue types. Thus, this quantitative analysis of organismal metabolism defines the relative contributions of nutrient fluxes in physiology, provides a resource for analysis of in vivo isotope tracing data, and concludes that glucose is the major nutrient used for catabolism in mammals.Competing Interest StatementThe authors have declared no competing interest.View Full Text

systems biology

Extracellular vesicles from monocyte/platelet aggregates modulate human atherosclerotic plaque responses

In atherosclerosis, a chronic disease characterized by lipid accumulation, fibrosis and vascular inflammation, extracellular vesicles (EVs) are emerging as key players in different stages of disease development. Here we provide evidence that EVs released by mixed aggregates of monocytes and platelets in response to TNF- are both CD14+ and CD41+. Tempering platelet activation with Iloprost impacted the quality and quantity of EV produced. Proteomics of EVs from cells activated with TNF- alone or in presence Iloprost revealed distinct proteome, with selective hits like gelsolin. EVs from TNF- stimulated monocytes augmented release of cytokines, and modulated more than 500 proteins by proteomics, when added to human atherosclerotic plaques. In contrast, EVs generated by TNF- and Iloprost produced minimal plaque activation. In conclusion, attenuating platelet activation has an effect on EV composition released from monocyte/platelet aggregates with downstream modulation of their pro-inflammatory actions and contribution to the development and progression of atherosclerosis.

immunology

Measurement of organ-specific and acute-phase blood protein levels in early Lyme disease

Lyme disease results from infection of humans with the spirochete Borrelia burgdorferi. The first and most common clinical manifestation is the circular, inflamed skin lesion referred to as erythema migrans; later manifestations result from infections of other body sites. Laboratory diagnosis of Lyme disease can be challenging in patients with erythema migrans because of the time delay in the development of specific diagnostic antibodies against Borrelia. Reliable blood biomarkers for the early diagnosis of Lyme disease in patients with erythema migrans are needed. Here, we performed selected reaction monitoring, a targeted mass spectrometry-based approach, to measure selected proteins that 1) are known to be predominantly expressed in one organ (i.e., organ-specific blood proteins) and whose blood concentrations may change as a result of Lyme disease, or 2) are involved in acute immune responses. In a longitudinal cohort of 40 Lyme disease patients and 20 healthy controls, we identified 10 proteins with significantly altered serum levels in patients at the time of diagnosis, and we also developed a 10-protein panel identified through multivariate analysis. In an independent cohort of patients with erythema migrans, six of these proteins, APOA4, C9, CRP, CST6, PGLYRP2 and S100A9, were confirmed to show significantly altered serum levels in patients at time of presentation. Nine of the 10 proteins from the multivariate panel were also verified in the second cohort. These proteins, primarily innate immune response proteins or proteins specific to liver, skin or white blood cells, may serve as candidate blood biomarkers requiring further validation to aid in the laboratory diagnosis of early Lyme disease.

systems biology