Hypothalamus proteomics from mouse models with obesity and anorexia reveals therapeutic targets of appetite regulation

Objective: This study examined the proteomic profile of the hypothalamus in mice exposed to a high-fat diet (HFD) or with the anorexia of acute illness. This comparison could provide insight on the effects of these two opposite states of energy balance on appetite regulation.Methods: Four to six-week-old male C56BL/6J mice were fed a normal (control 1 group; n=7) or a HFD (HFD group; n=10) for 8 weeks. The control 2 (n=7) and lipopolysaccharide (LPS) groups (n=10) were fed a normal diet for 8 weeks before receiving an injection of saline and LPS, respectively. Hypothalamic regions were analysed using a quantitative proteomics method based on a combination of techniques including iTRAQ stable isotope labeling, orthogonal two-dimensional liquid chromatography hyphenated with nanospray ionization and high-resolution mass spectrometry. Key proteins were validated with quantitative PCR.Results: Quantitative proteomics of the hypothalamous regions profiled a total of 9249 protein groups (q<0.05). Of these, 7718 protein groups were profiled with a minimum of two unique peptides for each. Hierachical clustering of the differentiated proteome revealed distinct proteomic signatures for the hypothalamus under the HFD and LPS nutritional conditions. Literature research with in silico bioinformatics interpretation of the differentiated proteome identified key biological relevant proteins and implicated pathways. Furthermore, the study identified potential pharmacologic targets. In the LPS groups, the anorexigen pro-opiomelanocortin was downregulated. In mice with obesity, nuclear factor-?B, glycine receptor subunit alpha-4 (GlyR) and neuropeptide Y levels were elevated, whereas serotonin receptor 1B levels decreased.Conclusions: High-precision quantitative proteomics revealed that under acute systemic inflammation in the hypothalamus as a response to LPS, homeostatic mechanisms mediating loss of appetite take effect. Conversely, under chronic inflammation in the hypothalamus as a response to HFD, mechanisms mediating a sustained ‘perpetual cycle’ of appetite enhancement were observed. The GlyR protein may constitute a novel treatment target for the reduction of central orexigenic signals in obesity

Peripheral Effects of FAAH Deficiency on Fuel and Energy Homeostasis: Role of Dysregulated Lysine Acetylation

FAAH (fatty acid amide hydrolase), primarily expressed in the liver, hydrolyzes the endocannabinoids fatty acid ethanolamides (FAA). Human FAAH gene mutations are associated with increased body weight and obesity. In our present study, using targeted metabolite and lipid profiling, and new global acetylome profiling methodologies, we examined the role of the liver on fuel and energy homeostasis in whole body FAAH(-/-) mice.FAAH(-/-) mice exhibit altered energy homeostasis demonstrated by decreased oxygen consumption (Indirect calorimetry). FAAH(-/-) mice are hyperinsulinemic and have adipose, skeletal and hepatic insulin resistance as indicated by stable isotope phenotyping (SIPHEN). Fed state skeletal muscle and liver triglyceride levels was increased 2-3 fold, while glycogen was decreased 42% and 57% respectively. Hepatic cholesterol synthesis was decreased 22% in FAAH(-/-) mice. Dysregulated hepatic FAAH(-/-) lysine acetylation was consistent with their metabolite profiling. Fasted to fed increases in hepatic FAAH(-/-) acetyl-CoA (85%, p<0.01) corresponded to similar increases in citrate levels (45%). Altered FAAH(-/-) mitochondrial malate dehydrogenase (MDH2) acetylation, which can affect the malate aspartate shuttle, was consistent with our observation of a 25% decrease in fed malate and aspartate levels. Decreased fasted but not fed dihydroxyacetone-P and glycerol-3-P levels in FAAH(-/-) mice was consistent with a compensating contribution from decreased acetylation of fed FAAH(-/-) aldolase B. Fed FAAH(-/-) alcohol dehydrogenase (ADH) acetylation was also decreased.Whole body FAAH deletion contributes to a pre-diabetic phenotype by mechanisms resulting in impairment of hepatic glucose and lipid metabolism. FAAH(-/-) mice had altered hepatic lysine acetylation, the pattern sharing similarities with acetylation changes reported with chronic alcohol treatment. Dysregulated hepatic lysine acetylation seen with impaired FAA hydrolysis could support the liver's role in fostering the pre-diabetic state, and may reflect part of the mechanism underlying the hepatic effects of endocannabinoids in alcoholic liver disease mouse models

Synthesis, characterization and crystal structure of novel mononuclear peroxotungsten(VI) complexes. Insulinomimetic activity of W(VI) and Nb(V) peroxo complexes

Two new mononuclear peroxo complexes of tungsten of the formula (gu)2[WO2(O2)2] (1) and (gu)[WO(O2)2(quin-2-c)] (2a) (where gu+ = guanidinium ion, CN3 H6+ and quin-2-c = quinoline-2-carboxylate ion) have been synthesized and characterized by elemental analysis, infrared, Raman, UV-visible and 1H NMR spectroscopies. The crystal structure of (gu)[WO(O2)2(quin-2-c)] · H2O (2b) determined by X-ray diffraction indicates that the side-on peroxo groups and the bidentate quinaldate ligand bind the W(VI) centre leading to an hepta coordination mode. The guanidinium ion occurring as a counterion and the hydrogen-bound interactions stabilize the complexes. The in vitro insulin-mimetic effect of the complexes has been evaluated by the inhibitory effect on free fatty acid release in isolated fat adipocytes treated with epinephrine. Moreover the niobate analogues, synthesized and characterized previously, (gu)3[Nb(O2)4] and (gu)2[Nb(O2)3(quin-2-c)] · H2O have been tested for the insulin-like activity. © 2009 Elsevier Inc. All rights reserved

Synthesis of two dicopper(II) complexes of l-carnitine: The first structural determination of a metal complex containing l-carnitine

Two dimeric copper(II) complexes of the biologically important compound l-carnitine were isolated from ethanolic and aqueous solutions with formulas [Cu2(l-carnitine)2Cl2(H2O)2] · Cl2 (complex 1) and [Cu2(l-carnitine)4(H2O)2] · (ClO4)4 · H2O · CH2Cl2 (complex 2), respectively. Complex 1 was characterized in solid state by elemental analysis, thermal analysis (TG, DTG), IR and EPR as well as in solution with cationic and anionic ESMS, EPR, NMR and UV-Vis spectroscopies. For complex 2, crystals were isolated after recrystallization and characterized by X-ray crystallography, elemental analysis, IR and NMR spectroscopies. © 2006 Elsevier Ltd. All rights reserved

Photosensitized oxidation of bromide to bromine catalyzed by niobium pentachloride in methanol solution. Formation and crystal structure of the tetraphenylphosphonium tribromide

This article examines the photoproduction of bromine by UV-vis light irradiation in the presence of niobium pentachloride in methanol media, under aerobic conditions. The reaction of tetraphenylphosphonium bromide with niobium pentachloride in methanol, thus, produced the corresponding tribromide. X-ray studies were performed on the tribromide compound to confirm the oxidation reaction. To our knowledge, the homogeneous photocatalytic oxidation of halogen ions when niobium pentachloride is photosensitized is the first example of the photocatalytic properties of this reagent. The photo-oxidation of the halogen ions was carried out under several conditions. The nearly linear oxo-bridges seem to favour this photocatalytic action. © 2007 Elsevier B.V. All rights reserved

Bis(tetraphenylphosphonium) bis(1-carboxybenzene-2,3-diolato- κ2O,O′)-cis-dioxomolybdate(VI)

The title compound, (C24H20P)2[Mo(C 7H4O4), contains a distorted octahedral molybdenum(VI) complex having the characteristic ds-MoO22+ group and the ligand 2,3-dihydroxy-benzoic acid coordinated through the two phenolate O atoms, while the carboxyl group is not deprotonated. No π-π overlap between the benzene rings of the ligands or those of the tetraphenylphosphonium ions is observed. © 2006 International Union of Crystallography All rights reserved

Anandamide increases the differentiation of rat adipocytes and causes PPARλ and cB1 receptor upregulation

Anandamide (N-arachidonoylethanolamine, AEA) or its metabolites participate in energy balance mainly through feeding modulation. In addition, AEA has been found to increase 3T3?L1 adipocyte differentiation process. In this study, the effect of AEA, R(+)-methanandamide (R(+)-mAEA), URB597, and indomethacin on primary rat adipocyte differentiation was evaluated by a flow cytometry method and by Oil Red-O staining. Reverse transcription-PCR and western blotting analysis were performed in order to study the effect of AEA on peroxisome proliferator?activated receptor (PPAR)λ2, cannabinoid receptors (CBRs), fatty acid amidohydrolase (FAAH), and cyclooxygenase-2 (COX-2) expression, during the differentiation process. AEA increased adipocyte differentiation in primary cell cultures in a concentration- and time-dependent manner and induced PPAR λ2 gene expression, confirming findings with 3T3?L1 cell line. CB1R, FAAH, and COX-2 expression was also increased while CB2R expression was decreased. Inhibition of FAAH and COX-2 attenuated the AEA-induced differentiation. Our findings indicate that AEA regulates energy homeostasis not only by appetite modulation but may also regulate adipocyte differentiation and phenotype. © 2009 The Obesity Society

Hypothalamus proteomics from mouse models with obesity and anorexia reveals therapeutic targets of appetite regulation

OBJECTIVE: This study examined the proteomic profile of the hypothalamus in mice exposed to a high-fat diet (HFD) or with the anorexia of acute illness. This comparison could provide insight on the effects of these two opposite states of energy balance on appetite regulation. METHODS: Four to six-week-old male C56BL/6J mice were fed a normal (control 1 group; n = 7) or a HFD (HFD group; n = 10) for 8 weeks. The control 2 (n = 7) and lipopolysaccharide (LPS) groups (n = 10) were fed a normal diet for 8 weeks before receiving an injection of saline and LPS, respectively. Hypothalamic regions were analysed using a quantitative proteomics method based on a combination of techniques including iTRAQ stable isotope labeling, orthogonal two-dimensional liquid chromatography hyphenated with nanospray ionization and high-resolution mass spectrometry. Key proteins were validated with quantitative PCR. RESULTS: Quantitative proteomics of the hypothalamous regions profiled a total of 9249 protein groups (q &lt; 0.05). Of these, 7718 protein groups were profiled with a minimum of two unique peptides for each. Hierachical clustering of the differentiated proteome revealed distinct proteomic signatures for the hypothalamus under the HFD and LPS nutritional conditions. Literature research with in silico bioinformatics interpretation of the differentiated proteome identified key biological relevant proteins and implicated pathways. Furthermore, the study identified potential pharmacologic targets. In the LPS groups, the anorexigen pro-opiomelanocortin was downregulated. In mice with obesity, nuclear factor-kappa B, glycine receptor subunit alpha-4 (GlyR) and neuropeptide Y levels were elevated, whereas serotonin receptor 1B levels decreased. CONCLUSIONS: High-precision quantitative proteomics revealed that under acute systemic inflammation in the hypothalamus as a response to LPS, homeostatic mechanisms mediating loss of appetite take effect. Conversely, under chronic inflammation in the hypothalamus as a response to HFD, mechanisms mediating a sustained `perpetual cycle&apos; of appetite enhancement were observed. The GlyR protein may constitute a novel treatment target for the reduction of central orexigenic signals in obesity

Preparation and characterization of the seven coordinate cadmium(II) complex [Cd(3,4-H2dhb)2(H2O) 3]·HCl·(3,4-H3dhb)·2.5H2O; the first structural determination of a complex containing the 3,4-dihydroxybenzoato(-1)(3,4-H2dhb-) ligand

The 1:2:1 reaction of CdCl2·2.5H2O with 3,4-dihydroxybenzoic acid (3,4-H3dhb) and KOH in PrnOH-H2O gave the unique, seven-coordinate cadmium(II) complex [Cd(3,4-H2dhb)2(H2O) 3]·HCl·(3,4-H3dhb)·2.5H2O as one of the products. Crystal structure and 13Cd NMR studies showed that 3,4-H2dhb- behaves as a bidentate chelate with ligated atoms being the carboxylate oxygens, but that seven-coordination is not retained in aqueous solution. Copyright © 1997 Elsevier Science Ltd