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GM-CSF driven myeloid cells in adipose tissue link weight gain and insulin resistance via formation of 2-aminoadipate
In a GM-CSF driven myeloid cell deficient mouse model (Csf2-/-) that has preserved insulin sensitivity despite increased adiposity, we used unbiased three-dimensional integration of proteome profiles, metabolic profiles, and gene regulatory networks to understand adipose tissue proteome-wide changes and their metabolic implications. Multi-dimensional liquid chromatography mass spectrometry and extended multiplex mass labeling was used to analyze proteomes of epididymal adipose tissues isolated from Csf2+/+ and Csf2-/- mice that were fed low fat, high fat, or high fat plus cholesterol diets for 8 weeks. The metabolic health (as measured by body weight, adiposity, plasma fasting glucose, insulin, triglycerides, phospholipids, total cholesterol levels, and glucose and insulin tolerance tests) deteriorated with diet for both genotypes, while mice lacking Csf2 were protected from insulin resistance. Regardless of diet, 30 mostly mitochondrial, branch chain amino acids (BCAA), and lysine metabolism proteins were altered between Csf2-/- and Csf2+/+ mice (FDR < 0.05). Lack of GM-CSF driven myeloid cells lead to reduced adipose tissue 2-oxoglutarate dehydrogenase complex (DHTKD1) levels and subsequent increase in plasma 2-aminoadipate (2-AA) levels, both of which are reported to correlate with insulin resistance. Tissue DHTKD1 levels were >4-fold upregulated and plasma 2-AA levels were >2 fold reduced in Csf2-/- mice (p < 0.05). GM-CSF driven myeloid cells link peripheral insulin sensitivity to adiposity via lysine metabolism involving DHTKD1/2-AA axis in a diet independent manner
Extended Multiplexing of Tandem Mass Tags (TMT) Labeling Reveals Age and High Fat Diet Specific Proteome Changes in Mouse Epididymal Adipose Tissue*
The lack of high-throughput methods to analyze the adipose tissue protein composition limits our understanding of the protein networks responsible for age and diet related metabolic response. We have developed an approach using multiple-dimension liquid chromatography tandem mass spectrometry and extended multiplexing (24 biological samples) with tandem mass tags (TMT) labeling to analyze proteomes of epididymal adipose tissues isolated from mice fed either low or high fat diet for a short or a long-term, and from mice that aged on low versus high fat diets. The peripheral metabolic health (as measured by body weight, adiposity, plasma fasting glucose, insulin, triglycerides, total cholesterol levels, and glucose and insulin tolerance tests) deteriorated with diet and advancing age, with long-term high fat diet exposure being the worst. In response to short-term high fat diet, 43 proteins representing lipid metabolism (e.g. AACS, ACOX1, ACLY) and red-ox pathways (e.g. CPD2, CYP2E, SOD3) were significantly altered (FDR < 10%). Long-term high fat diet significantly altered 55 proteins associated with immune response (e.g. IGTB2, IFIT3, LGALS1) and rennin angiotensin system (e.g. ENPEP, CMA1, CPA3, ANPEP). Age-related changes on low fat diet significantly altered only 18 proteins representing mainly urea cycle (e.g. OTC, ARG1, CPS1), and amino acid biosynthesis (e.g. GMT, AKR1C6). Surprisingly, high fat diet driven age-related changes culminated with alterations in 155 proteins involving primarily the urea cycle (e.g. ARG1, CPS1), immune response/complement activation (e.g. C3, C4b, C8, C9, CFB, CFH, FGA), extracellular remodeling (e.g. EFEMP1, FBN1, FBN2, LTBP4, FERMT2, ECM1, EMILIN2, ITIH3) and apoptosis (e.g. YAP1, HIP1, NDRG1, PRKCD, MUL1) pathways. Using our adipose tissue tailored approach we have identified both age-related and high fat diet specific proteomic signatures highlighting a pronounced involvement of arginine metabolism in response to advancing age, and branched chain amino acid metabolism in early response to high fat feeding. Data are available via ProteomeXchange with identifier PXD005953
Unique Proteomic Signatures Distinguish Macrophages and Dendritic Cells
Monocytes differentiate into heterogeneous populations of tissue macrophages and dendritic cells (DCs) that regulate inflammation and immunity. Identifying specific populations of myeloid cells in vivo is problematic, however, because only a limited number of proteins have been used to assign cellular phenotype. Using mass spectrometry and bone marrow-derived cells, we provided a global view of the proteomes of M-CSF-derived macrophages, classically and alternatively activated macrophages, and GM-CSF-derived DCs. Remarkably, the expression levels of half the plasma membrane proteins differed significantly in the various populations of cells derived in vitro. Moreover, the membrane proteomes of macrophages and DCs were more distinct than those of classically and alternatively activated macrophages. Hierarchical cluster and dual statistical analyses demonstrated that each cell type exhibited a robust proteomic signature that was unique. To interrogate the phenotype of myeloid cells in vivo, we subjected elicited peritoneal macrophages harvested from wild-type and GM-CSF-deficient mice to mass spectrometric and functional analysis. Unexpectedly, we found that peritoneal macrophages exhibited many features of the DCs generated in vitro. These findings demonstrate that global analysis of the membrane proteome can help define immune cell phenotypes in vivo
The enteroinsular axis in glucose dependent insulinotropic polypeptide receptor knockout (GIPR-/-) miee
The incretins, glucose-dependent insulinotropic polypeptide (GIP) and glucagonlike
peptide-1 (GLP-1), are gut hormones that act via the enteroinsular axis to potentiate
insulin secretion from the pancreas in a glucose-dependent manner. Both GLP-1 and GIP
receptor knockout mice (GLP-1 R-/- and GIPR-/- respectively) have been generated to
investigate the physiological importance of this axis. Studies in this thesis were carried
out on GIP receptor knockout mice (GIPR-/-). Although reduced GIP action is a
component of type 2 diabetes, GIP receptor-deficient mice exhibit only moderately
impaired glucose tolerance. Thus, the present thesis was directed at investigating possible
compensatory mechanisms that take place within the enteroinsular axis in the absence of
GIP action. Fasting and 20t h minute OGTT serum GIP levels as well as duodenojejunal
GIP content were altered in GIPR-/- mice. Total serum GLP-1 levels and serum DPIV
activity in GIPR knockout mice were not significantly different from those in control
animals, either before or during a glucose tolerance test. However, insulin responses to
GLP-1 in pancreas perfusions and static islet incubations were significantly greater in
GIPR -/- than in +/+ mice (P<0.05), and GLP-1 induced cAMP production was also
elevated in the pancreatic islets of the knockout animals (P<0.05). Additionally,
pancreatic insulin content and insulin gene expression were reduced in GIPR-/- mice
compared to wild type (+/+) mice (P< 0.05). There was, however, no discernible
difference in GLP-1 receptor mRNA levels. Immunohistochemistry studies revealed a
normal distribution and localization of endocrine cells within the pancreatic islets of
GIPR-/- mice. Surprisingly, these studies showed an increase in islet area, when compared to total pancreatic area, in the -/- mice (P<0.05) with less intense staining for
insulin. In conclusion, the GIPR-/- mouse exhibits increased islet size and (3 cell
sensitivity to GLP-1 despite a decrease in pancreatic insulin protein content and gene
expression. These findings suggest a critical role for GIP in normal islet and (3 cell
function and development.Arts, Faculty ofPsychology, Department ofGraduat
Geochemistry and mineralogy approaches to characterize brick and its lake sediments sources: Antioch Roman City (Southern Turkey)
The Roman aqueduct of Antioch-on-the-Orontes (Southern Turkey) is situated close to the Antioch city. This last is located near the Amik Lake (Lake of Antioch) and close to the junction between the active Dead Sea fault and the East Anatolian fault. During the Roman period, the Amik Plain was more densely occupied than at any time in its history [1]. The study focuses on the bricks and the lake sediments characterization in order to determine the source area as well as the technical production used at this period. For this purpose, several bricks were sampled on different parts of the city's aqueducts. Furthermore, a core of about 6 m of sediments was also collected from the dried Amik Lake. The bricks were characterized through a mineralogical (XRD) and chemical (PIXE-PIGE) approaches. Unfired clay fraction remained as inclusion in the brick was separated and then analysed using XRD. Geochemical composition and clay mineralogy were performed on the raw sediments from the Amik Lake in order to compare the source area. Technological test will be performed on the raw clay sediments from the Amik Lake in the purpose to understand the production techniques used at this time. The age of the brick production was previously dated to the Roman Period [2]. The synthesis of all the data attested the Amik Lake sediment as the raw material for the bricks of the aqueduct. Clay mineral composition from the Roman period deposited in the lake is smectite, illite, kaolinite and small amount of mixed-layer clays. The similar clays composition is found in the remained clays on the brick used for the aqueduct construction. Fast and heterogeneous firing practice characterized the manufacturing of these materials due to the rapid need for the materials during the post-seismic repairs after earthquakes that are mentioned in historical written works.
[1] J. Casana, Geomorphology, 101, 429-442 (2008)
[2] Y. Benjelloun, J. de Sigoyer, J. Carlut, A. Hubert-Ferrari, H. Dessales, H. Pamir, V. Karabacak, Comptes Rendus Geoscience, 347, 170-180 (2015
Transcranial Doppler assessment of cerebral blood flow velocity in term newborns
Using the transcranial Doppler technique to assess postnatal changes in cerebral blood flow velocity, we studied the anterior cerebral artery, middle cerebral artery, and internal carotid artery of 31 healthy, term newborn infants. Normative values for the 1st, 3rd, and 5th days of life were determined. Cerebral blood flow velocity values in all three arteries examined correlated well with each other and we observed a statistically significant increase only in middle cerebral artery blood flow velocity between the 1st and 3rd, and 1st and 5th postnatal days. Thus, if we assume that flow velocities in various cerebral arteries undergo similar change, only one representative artery need be examined. The middle cerebral artery appears to be the vessel of choice. This choice simplifies the recording procedure, particularly in repeated examinations
High triglyceride to HDL cholesterol ratio is associated with increased coronary heart disease among White but not Black adults
Objective: Black adults are less likely than White adults to present with adverse lipid profiles and more likely to present with low-grade inflammation. The impact of race on the association between atherogenic lipid profiles, inflammation, and coronary heart disease (CHD) is unknown. Methods: We evaluated the association between high levels (>50th percentile) of high-sensitivity C-reactive protein (hsCRP) and of triglycerides to high density lipoprotein ratio (TG/HDL-C) and CHD events by race in the REasons for Geographic and Racial Differences in Stroke (REGARDS) cohort with 30,239 Black and White participants aged 45 and older. Results: Participants with both high hsCRP and high TG/HDL-C had highest rates of CHD (HR 1.84; 95% CI: 1.48, 2.29Â vs HR 1.52; 95% CI: 1.19, 1.94 in White vs Black participants respectively). Whereas isolated high hsCRP was associated with increased CHD risk in both races (HR 1.68; 95% CI: 1.31, 2.15 and HR 1.43; 95% CI: 1.13, 1.81 for White and Black participants respectively), isolated high TG/HDL was associated with increased CHD risk only in White participants (HR 1.44; 95% CI: 1.15, 1.79Â vs HR 1.01; 95% CI: 0.74, 1.38). Further, the effects of high hsCRP and high TG/HDL-C were additive, with inflammation being the driving variable for the association in both races. Conclusion: In both races, higher inflammation combined with adverse lipid profile is associated with greater CHD risk. Therefore, inflammation increases CHD risk in both races whereas dyslipidemia alone is associated with a greater risk in White but not in Black adults. hsCRP testing should be a standard feature of CHD risk assessment, particularly in Black patients