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Cincinnati, OH, United States

Deng X.,University of Cincinnati | Morris J.,Metabolic Diseases Institute | Chaton C.,University of Cincinnati | Schroder G.F.,Julich Research Center | And 2 more authors.
Journal of Biological Chemistry | Year: 2013

Background: Apolipoproteins are lipid emulsifiers with links to additional protective roles. Results: Small-angle x-ray scattering afforded structural information for full-length apoA-IV. Conclusion: In the head-to-tail dimer, the N/C-terminal globular domains modulate the twist and curvature of a central helical bundle. Significance: The lipid affinity of apoA-IV is regulated by opening and closing a molecular clasp.© 2013 by The American Society for Biochemistry and Molecular Biology, Inc.


Finan B.,Helmholtz Center for Environmental Research | Finan B.,TU Munich | Finan B.,Indiana University Bloomington | Ma T.,Indiana University Bloomington | And 37 more authors.
Science Translational Medicine | Year: 2013

We report the discovery and translational therapeutic efficacy of a peptide with potent, balanced co-agonism at both of the receptors for the incretin hormones glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). This unimolecular dual incretin is derived from an intermixed sequence of GLP-1 and GIP, and demonstrated enhanced antihyperglycemic and insulinotropic efficacy relative to selective GLP-1 agonists. Notably, this superior efficacy translated across rodent models of obesity and diabetes, including db/db mice and ZDF rats, to primates (cynomolgus monkeys and humans). Furthermore, this co-agonist exhibited synergism in reducing fat mass in obese rodents, whereas a selective GIP agonist demonstrated negligible weight-lowering efficacy. The unimolecular dual incretins corrected two causal mechanisms of diabesity, adiposity-induced insulin resistance and pancreatic insulin deficiency, more effectively than did selective mono-agonists. The duration of action of the unimolecular dual incretins was refined through site-specific lipidation or PEGylation to support less frequent administration. These peptides provide comparable pharmacology to the native peptides and enhanced efficacy relative to similarly modified selective GLP-1 agonists. The pharmacokinetic enhancement lessened peak drug exposure and, in combination with less dependence on GLP-1-mediated pharmacology, avoided the adverse gastrointestinal effects that typify selective GLP-1-based agonists. This discovery and validation of a balanced and high-potency dual incretin agonist enables a more physiological approach to management of diseases associated with impaired glucose tolerance.


Fumagalli S.,Metabolic Diseases Institute | Fumagalli S.,University of Paris Descartes | Ivanenkov V.V.,Metabolic Diseases Institute | Teng T.,Metabolic Diseases Institute | And 3 more authors.
Genes and Development | Year: 2012

Impairment of ribosome biogenesis leads to p53 induction and cell cycle arrest, a checkpoint involved in human disease. Induction of p53 is attributed to the binding and inhibition of human double minute 2 (Hdm2) by a subset of ribosomal proteins (RPs): RPS7, RPL5, RPL11, and RPL23. However, we found that only RPL11 or RPL5, in a mutually dependent manner, elicit this response. We show that depletion of RPS7 or RPL23, like depletion of other RPs, except for RPL11 and RPL5, induces a p53 response and that the effects of RPS7 and RPL23 on p53 induction reported earlier may be ascribed to inhibition of global translation. Moreover, we made the surprising observation that codepletion of two essential RPs, one from each subunit, but not the same subunit, leads to suprainduction of p53. This led to the discovery that the previously proposed RPL11-dependent mechanism of p53 induction, thought to be caused by abrogation of 40S biogenesis and continued 60S biogenesis, is still operating, despite abrogation of 60S biogenesis. This response leads to both a G1 block and a novel G2/M block not observed when disrupting either subunit alone. Thus, induction of p53 is mediated by distinct mechanisms, with the data pointing to an essential role for ribosomal subunits beyond translation. © 2012 by Cold Spring Harbor Laboratory Press.


Finan B.,Helmholtz Center for Environmental Research | Finan B.,TU Munich | Finan B.,Indiana University Bloomington | Yang B.,Indiana University Bloomington | And 36 more authors.
Nature Medicine | Year: 2012

We report the development of a new combinatorial approach that allows for peptide-mediated selective tissue targeting of nuclear hormone pharmacology while eliminating adverse effects in other tissues. Specifically, we report the development of a glucagon-like peptide-1 (GLP-1)-estrogen conjugate that has superior sex-independent efficacy over either of the individual hormones alone to correct obesity, hyperglycemia and dyslipidemia in mice. The therapeutic benefits are driven by pleiotropic dual hormone action to improve energy, glucose and lipid metabolism, as shown by loss-of-function models and genetic action profiling. Notably, the peptide-based targeting strategy also prevents hallmark side effects of estrogen in male and female mice, such as reproductive endocrine toxicity and oncogenicity. Collectively, selective activation of estrogen receptors in GLP-1 - targeted tissues produces unprecedented efficacy to enhance the metabolic benefits of GLP-1 agonism. This example of targeting the metabolic syndrome represents the discovery of a new class of therapeutics that enables synergistic co-agonism through peptide-based selective delivery of small molecules. Although our observations with the GLP-1-estrogen conjugate justify translational studies for diabetes and obesity, the multitude of other possible combinations of peptides and small molecules may offer equal promise for other diseases. © 2012 Nature America, Inc.


Kirchner H.,Metabolic Diseases Institute | Hofmann S.M.,Metabolic Diseases Institute | Fischer-Rosinsky A.,Charite - Medical University of Berlin | Hembree J.,Metabolic Diseases Institute | And 11 more authors.
Diabetes | Year: 2012

Although obesity rates are rapidly rising, caloric restriction remains one of the few safe therapies. Here we tested the hypothesis that obesity-associated disorders are caused by increased adipose tissue as opposed to excess dietary lipids. Fat mass (FM) of lean C57B6 mice fed a high-fat diet (HFD; FMC mice) was "clamped" to match the FM of mice maintained on a low-fat diet (standard diet [SD] mice). FMC mice displayed improved glucose and insulin tolerance as compared with ad libitum HFD mice (P < 0.001) or SD mice (P < 0.05). These improvements were associated with fewer signs of inflammation, consistent with the less-impaired metabolism. In follow-up studies, diet-induced obese mice were food restricted for 5 weeks to achieve FM levels identical with those of age-matched SD mice. Previously, obese mice exhibited improved glucose and insulin tolerance but showed markedly increased fasting-induced hyperphagia (P < 0.001). When mice were given ad libitum access to the HFD, the hyperphagia of these mice led to accelerated body weight gain as compared with otherwise matched controls without a history of obesity. These results suggest that although caloric restriction on a HFD provides metabolic benefits, maintaining those benefits may require lifelong continuation, at least in individuals with a history of obesity. © 2012 by the American Diabetes Association.

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