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Background Factor XIa (FXIa) is an emerging therapeutic target, and FXIa inhibition is a promising mechanism to improve therapeutic index over current anticoagulants. Milvexian (BMS-986177/JNJ-70033093) is an oral small-molecule FXIa inhibitor. Objective Milvexian's antithrombotic efficacy was characterized in a rabbit arteriovenous (AV) shunt model of venous thrombosis and compared with the factor Xa inhibitor apixaban and the direct thrombin inhibitor dabigatran. Methods The AV shunt model of thrombosis was conducted in anesthetized rabbits. Vehicle or drugs were administered as intravenous bolus plus a continuous infusion. Thrombus weight was the primary efficacy endpoint. Ex vivo activated partial thromboplastin time (aPTT), prothrombin time (PT), and thrombin time (TT) were measured as the pharmacodynamic responses. Results Milvexian dose dependently reduced thrombus weights by 34.3 ± 7.9, 51.6 ± 6.8 (p Conclusion Results demonstrate that milvexian is an effective anticoagulant for prevention of venous thrombosis in the rabbit model, which supports the utility of milvexian in venous thrombosis, as seen in the phase 2 clinical study.

Peptide-based analogues of the gut-derived incretin hormone, glucagon-like peptide 1 (GLP1), stimulate insulin secretion in a glucose-dependent manner. Currently marketed GLP1 receptor (GLP1R) agonists are safe and effective in the management of Type 2 diabetes but often offer only modest weight loss. This has prompted the search for safe and effective alternatives to enhance the weight loss component of these treatments. We have demonstrated that concomitant activation GLP1R and the glucagon receptor (GCGR) can improve glucose metabolism and provide superior weight loss when compared to selective GLP1R agonism in preclinical species. This paper will highlight chemistry structure-activity relationship optimization and summarize in vivo efficacy studies toward the discovery of a once daily balanced dual agonist

Purpose: Adipocytes represent one of the most abundant constituents of the mammary gland. They are essential for mammary tumor growth and survival. Metabolically, one of the more important fat-derived factors (“adipokines”) is adiponectin (APN). Serum concentrations of APN negatively correlate with body mass index and insulin resistance. To explore the association of APN with breast cancer and tumor angiogenesis, we took an in vivo approach aiming to study its role in the mouse mammary tumor virus (MMTV)-polyoma middle T antigen (PyMT) mammary tumor model.Experimental Design: We compared the rates of tumor growth in MMTV-PyMT mice in wild-type and APN-null backgrounds.Results: Histology and micro-positron emission tomography imaging show that the rate of tumor growth is significantly reduced in the absence of APN at early stages. PyMT/APN knockout mice exhibit a reduction in their angiogenic profile resulting in nutrient deprivation of the tumors and tumor-associated cell death. Surprisingly, in more advanced malignant stages of the disease, tumor growth develops more aggressively in mice lacking APN, giving rise to a larger tumor burden, an increase in the mobilization of circulating endothelial progenitor cells, and a gene expression fingerprint indicative of more aggressive tumor cells.Conclusions: These observations highlight a novel important contribution of APN in mammary tumor development and angiogenesis, indicating that APN has potent angio-mimetic properties in tumor vascularization. However, in tumors deprived of APN, this antiangiogenic stress results in an adaptive response that fuels tumor growth through mobilization of circulating endothelial progenitor cells and the development of mechanisms enabling massive cell proliferation despite a chronically hypoxic microenvironment.

Supplementary Data from Proangiogenic Contribution of Adiponectin toward Mammary Tumor Growth In vivo

GDF15 is a circulating polypeptide associated with cellular stress, and recently linked to metabolic adaptation. GDF15 has a half-life of approximately 3 hours in and acts at the GFRAL receptor selectively expressed in the area postrema. To characterize the effects of sustained GFRAL agonism on food intake (FI) and body weight (BW), we developed a half-life extended analog of GDF15 (Compound H; CpdH) suitable for reduced dosing frequency and tested its effects in obese cynomolgus monkeys. Animals were treated once weekly for 12 weeks with 0.048, 0.16, or 1.6 mg/Kg of CpdH or with 0.02 mg/Kg of the long-acting GLP-1 analog dulaglutide as a positive control. FI was measured daily and BW was measured biweekly. Mechanism-based longitudinal exposure-response (E-R) modeling was performed to characterize the effects of CpdH and dulaglutide on FI and BW. The integrated novel model accounts for both acute, exposure-dependent effects of treatments to reduce FI and the compensatory changes in energy expenditure (EE) and FI that occur over time in response to weight loss. CpdH had approximately linear, dose-proportional pharmacokinetics with a half-life of ≈8 days and treatment with CpdH led to dose- and exposure-dependent reductions in FI and BW. The 1.6 mg/Kg CpdH dose reduced mean FI by 57.5% at 1 week and provided sustained FI reductions of 31.5% from weeks 9-12, leading to a peak reduction in BW of 16±5%. Dulaglutide had more modest effects on FI (reductions between 15-40%) and peak BW loss was 3.8±4.0%. Longitudinal modeling of both the FI and BW profiles suggested reductions in BW observed with both CpdH and dulaglutide were fully explained by the exposure-dependent reductions in FI without any increase in EE. Upon verification of pharmacokinetic/pharmacodynamic relationship established in monkeys and human for dulaglutide, we predicted that CpdH could reach double digit BW loss in human. In summary, treatment with a long-acting GDF15 analog led to sustained dose- and exposure-dependent reductions in food intake in a monkey model of obesity and holds potential for effective clinical obesity pharmacotherapy.Significance StatementGDF15 activation of GFRAL receptors in the hindbrain controls food intake and body weight. Here we describe the effect and durability of a circulating half-life extended analog of GDF15 (Compound H) on food intake and body weight loss in a spontaneously obese cynomolgus monkey model. Inclusion of a translational treatment arm with a weight loss agent, dulaglutide, permitted pharmacokinetic/pharmacodynamic modeling and comparison of both GDF15 and GLP-1 based weight loss mechanisms, and development of an allometric scaling based mathematical model to estimate the efficacy of Compound H in human obese subjects.

In humans, weight loss and pioglitazone treatment improve nonalcoholic steatohepatitis (NASH). We developed an obese, insulin resistant cynomolgus monkey model of NASH with fibrosis with a high fat/high cholesterol (HFHC) diet (with or without high fructose) and tested its responsiveness to caloric restriction or pioglitazone.First, two groups of monkeys (n=24/group) histologically proven NASH and fibrosis were fed the HFHC diet for 17 weeks. The treatment group was subjected to a 40% caloric restriction (CR) and switched from HFHC diet to a chow diet (DSCR). Paired liver biopsies were taken before and 17 weeks after DSCR. HFHC and DSCR groups lost 0.9% and 11.4% body weight, respectively. After 17 weeks, nonalcoholic fatty liver disease activity score (NAS) improvement was observed in 66.7% of the DSCR group versus 12.5% of the HFHC group (p0.001). Subsets of monkeys (9/group) had whole liver fat content assessed by MRI. Hepatic fat was reduced to 5.2% in the DSCR group versus 23.0% in the HFHC group (p=0.0001). Next, two groups of monkeys with histologically proven NASH and fibrosis were treated with vehicle (n=9) or pioglitazone (n=20) over 24 weeks. After 24 weeks, NAS improvement was seen in 30% of the pioglitazone group versus 0% of the vehicle group (p=0.08).Both weight loss induced by DSCR and treatment with pioglitazone improve histological features of NASH in a diet-induced cynomolgus monkey model. This model provides a translational preclinical model for testing novel NASH therapies. This article is protected by copyright. All rights reserved.

[Objective]: The mitochondrial fission protein Drp1 was proposed to promote NAFLD, as inhibition of hepatocyte Drp1 early in life prevents liver steatosis induced by high-fat diet in mice. However, whether Drp1-knockdown in older mice can reverse established NASH is unknown. [Methods]: N-acetylgalactosamine-siRNA conjugates, an FDA approved method to deliver siRNA selectively to hepatocytes, were used to knockdown hepatocyte-Drp1 in mice (NAG-Drp1si). NASH was induced in C57BL/6NTac mice by Gubra-Amylin-NASH diet (D09100310, 40% fat, 22% fructose and 2% cholesterol) and treatment with NAG-Drp1si was started at week 24 of diet. Circulating transaminases, liver histology, gene expression of fibrosis and inflammation markers, and hydroxyproline synthesis determined NASH severity. Liver NEFA and triglycerides were quantified by GC/MS. Mitochondrial function was determined by respirometry. Western blots of Oma1, Opa1, p-eIf2α, as well as transcriptional analyses of Atf4-regulated genes determined ISR engagement. [Results]: NAG-Drp1si treatment decreased body weight and induced liver inflammation in adult healthy mice. Increased hepatic Gdf15 production was the major contributor to body-weight loss caused by NAG-Drp1si treatment, as Gdf15 receptor deletion (Gfral KO) prevented the decrease in food intake and mitigated weight loss. NAG-Drp1si activated the Atf4-controlled integrated stress response (ISR) to increase hepatic Gdf15 expression. NAG-Drp1si in healthy mice caused ER stress and activated the mitochondrial protease Oma1, which are the ER and mitochondrial triggers that activate the Atf4-controlled ISR. Remarkably, induction of NASH was not sufficient to activate Oma1 in liver. However, NAG-Drp1si treatment was sufficient to activate Oma1 in adult mice with NASH, as well as exacerbating NASH-induced ER stress. Consequently, NAG-Drp1si treatment in mice with NASH led to higher ISR activation, exacerbated inflammation, fibrosis and necrosis. [Conclusion]: Drp1 mitigates NASH by decreasing ER stress, preventing Oma1 activation and ISR exacerbation. The elevation in Gdf15 actions induced by NAG-Drp1si might represent an adaptive response decreasing the nutrient load to liver when mitochondria are misfunctional. Our study argues against blocking Drp1 in hepatocytes to combat NASH., M.L. and O.S.S. are funded by Janssen Research and Development, LLC, ICD #M3229099 – 846328. O.S.S. is funded by R01 DK099618-05; R01 CA232056-01; R21AG060456-01; R21 AG063373-01.

Meal ingestion elicits a variety of neuronal, physiological and hormonal responses that differ in healthy, obese or diabetic individuals. The mixed meal tolerance test (MMTT) is a well-established method to evaluate pancreatic β-cell reserve and glucose homeostasis in both preclinical and clinical research in response to calorically defined meal. Nonhuman primates (NHPs) are highly valuable for diabetic research as they can naturally develop type 2 diabetes mellitus (T2DM) in a way similar to the onset and progression of human T2DM. The purpose of this study was to investigate the reproducibility and effects of a MMTT containing acetaminophen on plasma glucose, insulin, C-peptide, incretin hormones, lipids, acetaminophen appearance (a surrogate marker for gastric emptying) in 16 conscious obese cynomolgus monkeys (Macaca fascicularis). Plasma insulin, C-peptide, TG, aGLP-1, tGIP, PYY and acetaminophen significantly increased after meal/acetaminophen administration. A subsequent study in 6 animals showed that the changes of plasma glucose, insulin, C-peptide, lipids and acetaminophen were reproducible. There were no significant differences in responses to the MMTT among the obese NHPs with (n = 11) or without (n = 5) hyperglycemia. Our results demonstrate that mixed meal administration induces significant secretion of several incretins which are critical for maintaining glucose homeostasis. In addition, the responses to the MMTTs are reproducible in NHPs, which is important when the MMTT is used for evaluating post-meal glucose homeostasis in research.

Nonalcoholic fatty liver disease (NAFLD) ranges in severity from steatosis to NASH. NASH, which is characterized by steatosis, ballooning, inflammation (NAFLD Activity Score [NAS]), and frequently fibrosis, can progress to cirrhosis and hepatocellular carcinoma. Despite the unmet medical needs of NASH leading to end stage liver disease and increased risk for cardiovascular death, there are no approved treatments to date. In clinical trials, pioglitazone treatment (6-24 months) has led to NASH resolution and/or reduction in fibrosis. We developed a cynomolgus monkey (cyno) model of NASH by feeding a high fat/cholesterol diet for 2+ years and demonstrated accelerated disease progression by adding fructose to this diet. A total of 31 obese (mean±SD, 10.4±1.8 kg), insulin resistant (HOMA-IR: 29±32) cynos with NASH were used. Histological assessments of liver biopsies were used to characterize disease progression and response to therapy and compared to human studies. Baseline NAS of 5.6±0.9 was similar to those in NASH patients, whereas baseline fibrosis scores of 1.2±0.5 were slightly lower than values of ∼2 typically enrolled in Phase 2 trials. Cynos were treated daily with vehicle (n=10) or pioglitazone (3 mg/kg; n=21) for 6 months. Drug exposures 24 hours post-dose averaged 233±145 ng/mL, similar to that seen in humans (∼200 ng/mL) dosed with 45 mg. Adiponectin, a biomarker for PPARγ activation, increased ∼2-fold in treated cynos. NAS improvement (a decrease in NAS of ≥2 with changes in 2 or more components of NAS) was seen in 30% of treated cynos (p=0.08). No vehicle animals showed NAS improvement. Treated cynos showed significant decreases in ballooning, trends in decreases (p=0.07) in steatosis and inflammation, but no change in fibrosis whereas vehicle animals showed no changes or worsening. We have validated and benchmarked a novel cyno model for NASH that has characteristics similar to human pathology and responds to a treatment known to improve NASH in clinical trials. Disclosure R. Camacho: Employee; Self; Janssen Pharmaceuticals, Inc. D. Polidori: Employee; Self; Janssen Research and Development. Stock/Shareholder; Self; Janssen Research and Development. T. Chen: Employee; Self; Janssen Pharmaceuticals, Inc. B. Gao: Employee; Self; Janssen Pharmaceuticals, Inc. P. Wong: Employee; Self; Johnson & Johnson. Stock/Shareholder; Self; Merck & Co., Inc. J.A. Gabriel: Employee; Self; Kunming Biomed International (KBI). E. Zhu: None. T. Wang: None. A.R. Nawrocki: Employee; Self; Janssen Pharmaceuticals, Inc.

Nonalcoholic fatty liver disease (NAFLD) and its progression to nonalcoholic steatohepatitis (NASH) is highly prevalent in modern societies frequently consuming diets rich in fats and carbohydrates. NASH is characterized by liver steatosis, inflammation and increased risk for liver fibrosis in human. There is no single animal model available that encompasses the defining features of NASH; therefore, it is of importance to thoroughly characterize available rodent models for NASH research and new drug discovery. Foz/foz mice have a mutation in the Alms1 gene, a ubiquitous protein essential for proper primary cilium function. They have similar defects such as metabolic syndrome, NASH and liver fibrosis to human with the same gene mutation. To better characterize the model, foz/foz mice were fed with western diet (WD, D12079B) for various duration. Compared with WT mice, foz/foz mice on WD had (1) increased BW gain driven by hyperphagia; (2) insulin/leptin resistance with decreased adiponectin levels and hyperlipidemia; (3) increased fat mass and hepatomegaly; (4) increased liver enzymes and elevated TIMP1 in plasma; (5) Liver gene expressions profiles of foz/foz mice showed up-regulation of fibrogenic genes and Lipogenesis, inflammation genes. Histopathology assessment showed foz/foz mice developed severe hepatic steatosis and increased marker of macrophage populations (F4/80 IHC staining). liver collagen content was significantly increased at 16 and 24 wks post WD feeding (PSR staining) compared to wild type mice fed the same diet. Our results suggest that the foz/foz mouse model has robust hallmark features of NASH such as metabolic syndrome, steatohepatitis, and fibrosis. In addition, our data suggest the presence of metabolic complications in other organs as well, as foz/foz mice develop proteinuria over time. The WD-induced foz/foz model exhibits several clinically relevant features and serves as a translational model of NASH. Disclosure J. Liu: None. S. Wang: None. K.E. D’Aquino: Employee; Self; Janssen Pharmaceuticals, Inc. Employee; Spouse/Partner; Janssen Pharmaceuticals, Inc. N.H. Wallace: None. M.M. Rankin: Employee; Self; Janssen Pharmaceuticals, Inc. Stock/Shareholder; Self; Johnson & Johnson. F. Du: None. S.A. Hinke: Employee; Self; Janssen Pharmaceuticals, Inc. Stock/Shareholder; Self; Johnson & Johnson. K.A. Albarazanji: None. A.R. Nawrocki: Employee; Self; Janssen Pharmaceuticals, Inc.

An increased contribution of de novo lipogenesis (DNL) may play a role in cases of dyslipidemia and adipose accretion; this suggests that inhibition of fatty acid synthesis may affect clinical phenotypes. Since it is not clear whether modulation of one step in the lipogenic pathway is more important than another, the use of tracer methods can provide a deeper level of insight regarding the control of metabolic activity. Although [2H]water is generally considered a reliable tracer for quantifying DNL in vivo (it yields a homogenous and quantifiable precursor labeling), the relatively long half-life of body water is thought to limit the ability of performing repeat studies in the same subjects; this can create a bottleneck in the development and evaluation of novel therapeutics for inhibiting DNL. Herein, we demonstrate the ability to perform back-to-back studies of DNL using [2H]water. However, this work uncovered special circumstances that affect the data interpretation, i.e., it is possible to obtain seemingly negative values for DNL. Using a rodent model, we have identified a physiological mechanism that explains the data. We show that one can use [2H]water to test inhibitors of DNL by performing back-to-back studies in higher species [i.e., treat nonhuman primates with platensimycin, an inhibitor of fatty acid synthase]; studies also demonstrate the unsuitability of [13C]acetate.

Aberrant regulation of glucose production makes a critical contribution to the impaired glycemic control that is observed in type 2 diabetes. Although isotopic tracer methods have proven to be informative in quantifying the magnitude of such alterations, it is presumed that one must rely on venous access to administer glucose tracers which therein presents obstacles for the routine application of tracer methods in rodent models. Since intraperitoneal injections are readily used to deliver glucose challenges and/or dose potential therapeutics, we hypothesized that this route could also be used to administer a glucose tracer. The ability to then reliably estimate glucose flux would require attention toward setting a schedule for collecting samples and choosing a distribution volume. For example, glucose production can be calculated by multiplying the fractional turnover rate by the pool size. We have taken a step-wise approach to examine the potential of using an intraperitoneal tracer administration in rat and mouse models. First, we compared the kinetics of [U-13C]glucose following either an intravenous or an intraperitoneal injection. Second, we tested whether the intraperitoneal method could detect a pharmacological manipulation of glucose production. Finally, we contrasted a potential application of the intraperitoneal method against the glucose-insulin clamp. We conclude that it is possible to 1) quantify glucose production using an intraperitoneal injection of tracer and 2) derive a “glucose production index” by coupling estimates of basal glucose production with measurements of fasting insulin concentration; this yields a proxy for clamp-derived assessments of insulin sensitivity of endogenous production.

Obesity is associated with increased risk of diabetes and cardiovascular disease. Evidence is accumulating that significant WL (>10%) may reduce this risk. GDF15 is a secreted circulating polypeptide associated with energy balance. The receptor for GDF15, Gfral, is expressed in the area postrema and mediates the inhibitory effects of GDF15 on food intake. Compound H (CpdH) is a GDF15 agonist on a half-life extension platform, suitable for once-weekly dosing. We sought to test the durability of the food intake suppression and body weight loss with once weekly dosing of CpdH in the spontaneously obese cynomolgus non-human primate (NHP) model. As a translational control we included dulaglutide (dula), a long-acting GLP-1 agonist, to enable efficacy modeling and validation of the animal model. PK/PD simulations derived from single-dose lean and obese NHP studies were used for dose selection; CpdH or dula was administered SC once weekly in a biologic naïve spontaneously obese cynomolgus (population BMI 46.0±1.0Kg/m2 with 15.1±1.5% total body fat (n=32) at baseline). Chronic treatment of animals with CpdH at 1 and 10nmol/kg once weekly reduced food intake in a dose related manner relative to vehicle. A commensurate, sustained reduction in body weight (up to 16.2±4.9%) was observed at steady state exposures. The injection of dulaglutide control caused rapid, transient reduction in food intake and a 3.8% reduction in vehicle corrected body weight over 12 weeks. A dose-response relationship for CpdH was formally demonstrated. In conclusion, CpdH is a novel agent for the treatment of human obesity and type 2 diabetes. Unless otherwise noted, all abstracts presented at ENDO are embargoed until the date and time of presentation. For oral presentations, the abstracts are embargoed until the session begins. Abstracts presented at a news conference are embargoed until the date and time of the news conference. The Endocrine Society reserves the right to lift the embargo on specific abstracts that are selected for promotion prior to or during ENDO.

Physical activity promotes metabolic and cardiovascular health benefits that derive in part from the transcriptional responses to exercise that occur within skeletal muscle and other organs. There is interest in discovering a pharmacologic exercise mimetic that could imbue wellness and alleviate disease burden. However, the molecular physiology by which exercise signals the transcriptional response is highly complex, making it challenging to identify a single target for pharmacological mimicry. The current studies evaluated the transcriptome responses in skeletal muscle, heart, liver, and white and brown adipose to novel small molecule activators of AMPK (pan-activators for all AMPK isoforms) compared to that of exercise. A striking level of congruence between exercise and pharmacological AMPK activation was observed across the induced transcriptome of these five tissues. However, differences in acute metabolic response between exercise and pharmacologic AMPK activation were observed, notably for acute glycogen balances and related to the energy expenditure induced by exercise but not pharmacologic AMPK activation. Nevertheless, intervention with repeated daily administration of short-acting activation of AMPK was found to mitigate hyperglycemia and hyperinsulinemia in four rodent models of metabolic disease and without the cardiac glycogen accretion noted with sustained pharmacologic AMPK activation. These findings affirm that activation of AMPK is a key node governing exercise mediated transcription and is an attractive target as an exercise mimetic.

The 2 gut hormones glucagon-like peptide-1 (GLP-1) and peptide YY (PYY) are well known to be coexpressed, costored, and released together to coact in the control of key metabolic target organs. However, recently, it became clear that several other gut hormones can be coexpressed in the intestinal-specific lineage of enteroendocrine cells. Here, we focus on the anatomical and functional consequences of the coexpression of neurotensin with GLP-1 and PYY in the distal small intestine. Fluorescence-activated cell sorting analysis, laser capture, and triple staining demonstrated that GLP-1 cells in the crypts become increasingly multihormonal, ie, coexpressing PYY and neurotensin as they move up the villus. Proglucagon promoter and pertussis toxin receptor-driven cell ablation and reappearance studies indicated that although all the cells die, the GLP-1 cells reappear more quickly than PYY- and neurotensin-positive cells. High-resolution confocal fluorescence microscopy demonstrated that neurotensin is stored in secretory granules distinct from GLP-1 and PYY storing granules. Nevertheless, the 3 peptides were cosecreted from both perfused small intestines and colonic crypt cultures in response to a series of metabolite, neuropeptide, and hormonal stimuli. Importantly, neurotensin acts synergistically, ie, more than additively together with GLP-1 and PYY to decrease palatable food intake and inhibit gastric emptying, but affects glucose homeostasis in a more complex manner. Thus, neurotensin is a major gut hormone deeply integrated with GLP-1 and PYY, which should be taken into account when exploiting the enteroendocrine regulation of metabolism pharmacologically.

The free fatty acid receptor 1 (FFAR1) mediates fatty acid-induced insulin secretion from pancreatic β-cells. Numerous ligands have been investigated for their antidiabetic actions. The most advanced, fasiglifam (TAK-875), is a site 1 binding agonist that stimulates IPone and improves glycemic control in diabetic patients via glucose-dependent insulin secretion (GSIS). Recently, FFAR1 agonists were discovered that bind to site 3, stimulate IPone and cAMP and result in both insulin and glucagon-like peptide-1 (GLP-1) secretion. We hypothesized that this novel pharmacology would lead to superior glucose lowering relative to fasiglifam in diabetic monkeys. A selective FFAR1 agonist (CpdA) was discovered that activates rodent, cynomolgus and human FFAR1 receptors in vitro, triggering similar IPone and cAMP production. Incubation with CpdA but not fasiglifam restored insulin secretion in human islets from diabetic donors. Cpd A stimulates GLP-1 secretion in wild type but not GPR40 knockout mice, additionaly, as well as stimulates insulin secretion in ZDF rats. The ability of CpdA to control blood glucose was evaluated in diabetic cynomolgus monkeys during an oral glucose tolerance test after a single dose and repeated dosing for 7 days. Notably, the restoration of insulin secretion elicited by CpdA in diabetic human islets was recapitulated in vivo in diabetic monkeys and resulted in superior acute and chronic improvement in glucose tolerance relative to fasiglifam. In conclusion, administration of CpdA restores insulin secretion and produces robust improvement in glucose metabolism in diabetic rodents and monkeys. Thus, FFAR1 agonists represent a potential treatment for type 2 diabetes. Disclosure J. Liu: None. S.P. Lee: Employee; Self; Janssen Research & Development. T. Martin: Employee; Self; Janssen Research & Development. Stock/Shareholder; Self; Janssen Research & Development. B. Rady: Employee; Self; Janssen Research & Development. S. Meegalla: None. H. Huang: None. M.P. Winters: None. L.D. Norquay: Employee; Self; Janssen Research & Development. J. Qi: None. F. Du: None. A.R. Nawrocki: Employee; Self; Janssen Pharmaceuticals, Inc.. M. Player: None. A. Pocai: None.

An increased contribution of de novo lipogenesis (DNL) may play a role in cases of dyslipidemia and adipose accretion; this suggests that inhibition of fatty acid synthesis may affect clinical phenotypes. Since it is not clear whether modulation of one step in the lipogenic pathway is more important than another, the use of tracer methods can provide a deeper level of insight regarding the control of metabolic activity. Although [

Lipid lowering properties of glucagon have been reported. Blocking glucagon signaling leads to rise in plasma LDL levels. Here, we demonstrate the lipid lowering effects of acute dosing with Glp1r/Gcgr dual agonist (DualAG). All the experiments were performed in 25 week-old male diet-induced (60% kCal fat) obese mice. After 2 hrs of fasting, mice were injected subcutaneously with vehicle, liraglutide (25nmol/kg) and DualAG (25nmol/kg). De novo cholesterol and palmitate synthesis was measured by deuterium incorporation method using D2O. 13C18-oleate infusion was used for measuring fatty acid esterification. Simultaneous activation of Glp1r and Gcgr resulted in decrease in plasma triglyceride and cholesterol levels. DualAG enhanced hepatic LDLr protein levels, along with causing decrease in content of plasma ApoB48 and ApoB100. VLDL secretion, de novo palmitate synthesis and fatty acid esterification decreased with acute DualAG treatment. On the other hand, ketone levels were elevated with DualAG treatment, indicating increased fatty acid oxidation. Lipid relevant changes were absent in liraglutide treated group. In an acute treatment, DualAG demonstrated significant impact on lipid homeostasis, specifically on hepatic uptake, VLDL secretion and de novo synthesis. These effects collectively reveal that lipid lowering abilities of DualAG are primarily through glucagon signaling and are liver centric.

Continuous glucose monitoring (CGM) is a platform to measure blood glucose (BG) levels continuously in real time with high enough resolution to document their underlying fluctuations. Multiscale entropy (MSE) analysis has been proposed as a measure of time-series complexity, and when applied to clinical CGM data, MSE analysis revealed that diabetic patients have lower MSE complexity in their BG time series than healthy subjects. To determine if the clinical observations on complexity of glucose dynamics can be back-translated to relevant preclinical species used routinely in diabetes drug discovery, we performed CGM in both mouse (ob/ob) and rat (Zucker Diabetic Fatty, ZDF) models of diabetes. We demonstrate that similar to human data, the complexity of glucose dynamics is also decreased in diabetic mice and rats. We show that low complexity of glucose dynamics is not simply a reflection of high glucose values, but rather reflective of the underlying disease state (i.e. diabetes). Finally, we demonstrate for the first time that the complexity of glucose fluctuations in ZDF rats, as probed by MSE analysis, is decreased prior to the onset of overt diabetes, although complexity undergoes further decline during the transition to frank diabetes. Our study suggests that MSE could serve as a novel biomarker for the progression to diabetes and that complexity studies in preclinical models could offer a new paradigm for early differentiation, and thereby, selection of appropriate clinical candidate molecules to be tested in human clinical trials.

Objectives Platensimycin (PTM) is a natural antibiotic produced by Streptomyces platensis that selectively inhibits bacterial and mammalian fatty acid synthase (FAS) without affecting synthesis of other lipids. Recently, we reported that oral administration of PTM in mouse models (db/db and db/+) with high de novo lipogenesis (DNL) tone inhibited DNL and enhanced glucose oxidation, which in turn led to net reduction of liver triglycerides (TG), reduced ambient glucose, and improved insulin sensitivity. The present study was conducted to explore translatability and the therapeutic potential of FAS inhibition for the treatment of diabetes in humans. Methods We tested PTM in animal models with different DNL tones, i.e. intrinsic synthesis rates, which vary among species and are regulated by nutritional and disease states, and confirmed glucose-lowering efficacy of PTM in lean NHPs with quantitation of liver lipid by MRS imaging. To understand the direct effect of PTM on liver metabolism, we performed ex vivo liver perfusion study to compare FAS inhibitor and carnitine palmitoyltransferase 1 (CPT1) inhibitor. Results The efficacy of PTM is generally reproduced in preclinical models with DNL tones comparable to humans, including lean and established diet-induced obese (eDIO) mice as well as non-human primates (NHPs). Similar effects of PTM on DNL reduction were observed in lean and type 2 diabetic rhesus and lean cynomolgus monkeys after acute and chronic treatment of PTM. Mechanistically, PTM lowers plasma glucose in part by enhancing hepatic glucose uptake and glycolysis. Teglicar, a CPT1 inhibitor, has similar effects on glucose uptake and glycolysis. In sharp contrast, Teglicar but not PTM significantly increased hepatic TG production, thus caused liver steatosis in eDIO mice. Conclusions These findings demonstrate unique properties of PTM and provide proof-of-concept of FAS inhibition having potential utility for the treatment of diabetes and related metabolic disorders.

GPR105, a G protein-coupled receptor for UDP-glucose, is highly expressed in several human tissues and participates in the innate immune response. Because inflammation has been implicated as a key initial trigger for type 2 diabetes, we hypothesized that GPR105 (official gene name: P2RY14) might play a role in the initiation of inflammation and insulin resistance in obesity. To this end, we investigated glucose metabolism in GPR105 knockout (KO) and wild-type (WT) mice fed a high-fat diet (HFD). We also examined whether GPR105 regulates macrophage recruitment to liver or adipose tissues by in vivo monocyte tracking and in vitro chemotaxis experiments, followed by transplantation of bone marrow from either KO or WT donors to WT recipients. Our data show that genetic deletion of GPR105 confers protection against HFD-induced insulin resistance, with reduced macrophage infiltration and inflammation in liver, and increased insulin-stimulated Akt phosphorylation in liver, muscle, and adipose tissue. By tracking monocytes from either KO or WT donors, we found that fewer KO monocytes were recruited to the liver of WT recipients. Furthermore, we observed that uridine 5-diphosphoglucose enhanced the in vitro migration of bone marrow-derived macrophages from WT but not KO mice, and that plasma uridine 5-diphosphoglucose levels were significantly higher in obese versus lean mice. Finally, we confirmed that insulin sensitivity improved in HFD mice with a myeloid cell-specific deletion of GPR105. These studies indicate that GPR105 ablation mitigates HFD-induced insulin resistance by inhibiting macrophage recruitment and tissue inflammation. Hence GPR105 provides a novel link between innate immunity and metabolism.

Left ventricular hypertrophy (LVH) is a risk factor for cardiovascular disease, a leading cause of death. Alterations in endothelial nitric oxide synthase (eNOS), an enzyme involved in regulating vascular tone, and in adiponectin, an adipocyte-derived secretory factor, are associated with cardiac remodeling. Deficiency of eNOS is associated with hypertension and LVH. Adiponectin exhibits vaso-protective, anti-inflammatory, and anti-atherogenic properties. We hypothesized that increased levels of adiponectin would alleviate cardiac pathology resulting from eNOS deficiency, while decreased levels of adiponectin would exacerbate the pathology. Male and female mice, deficient in eNOS, and either lacking or over-expressing adiponectin, were fed high fat diet (HFD) or normal chow. Cardiac magnetic resonance imaging was performed to serially assess heart morphology and function up to 40 weeks of age. Thirty-two weeks of HFD feeding led to significantly greater LV mass in male mice deficient in eNOS and either lacking or over-expressing adiponectin. Heart function was significantly reduced when the mice were deficient in either eNOS, adiponectin or both eNOS and adiponectin; for female mice, heart function was only reduced when both eNOS and adiponectin were lacking. Thus, while over-expression of adiponectin in the eNOS deficient HFD fed male mice preserved function at the expense of significantly increased LV mass, female mice were protected from decreased function and increased LVH by over-expression of adiponectin. Our results demonstrate a sexual dimorphism in response of the heart to alterations in eNOS and adiponectin during high fat feeding and suggest that adiponectin might require eNOS for some of its metabolic effects.

Purpose: Adipocytes represent one of the most abundant constituents of the mammary gland. They are essential for mammary tumor growth and survival. Metabolically, one of the more important fat-derived factors (“adipokines”) is adiponectin (APN). Serum concentrations of APN negatively correlate with body mass index and insulin resistance. To explore the association of APN with breast cancer and tumor angiogenesis, we took an in vivo approach aiming to study its role in the mouse mammary tumor virus (MMTV)-polyoma middle T antigen (PyMT) mammary tumor model. Experimental Design: We compared the rates of tumor growth in MMTV-PyMT mice in wild-type and APN-null backgrounds. Results: Histology and micro-positron emission tomography imaging show that the rate of tumor growth is significantly reduced in the absence of APN at early stages. PyMT/APN knockout mice exhibit a reduction in their angiogenic profile resulting in nutrient deprivation of the tumors and tumor-associated cell death. Surprisingly, in more advanced malignant stages of the disease, tumor growth develops more aggressively in mice lacking APN, giving rise to a larger tumor burden, an increase in the mobilization of circulating endothelial progenitor cells, and a gene expression fingerprint indicative of more aggressive tumor cells. Conclusions: These observations highlight a novel important contribution of APN in mammary tumor development and angiogenesis, indicating that APN has potent angio-mimetic properties in tumor vascularization. However, in tumors deprived of APN, this antiangiogenic stress results in an adaptive response that fuels tumor growth through mobilization of circulating endothelial progenitor cells and the development of mechanisms enabling massive cell proliferation despite a chronically hypoxic microenvironment.

The adipocyte has pleiotropic functions beyond the storage of energy in times of nutrient abundance. Considerable efforts in adipocyte biology within the past ten years have emphasized the important role of adipose tissue in processes as diverse as energy metabolism, inflammation and cancer. Adipocytes are able to communicate with the brain and peripheral tissues implementing metabolic signals such as satiety, food intake and energy expenditure. Despite its huge pharmacological potential, only a small number of clinical applications interfere directly with adipocyte physiology. Here, we want to highlight various areas of adipocyte physiology that have not yet been explored pharmacologically and emphasize some of the limitations associated with these pharmacotherapies.

Dexamethasone (Dex) is a potent and long-acting glucocorticoid in terms of anti-inflammatory activity without substantial sodium retaining effect. Here, we examine the ability of the 11beta-hydroxyglucocorticoids Dex and cortisol and their 11-keto forms 11-ketodexamethasone (11-ketoDex) and cortisone to bind to glucocorticoid receptors (GR) and mineralocorticoid receptors (MR) and to mediate nuclear translocation and transactivation of a reporter-gene. Unlike cortisone, the 11-ketosteroid 11-ketoDex acts as a potent GR agonist, comparable to Dex and cortisol. Transactivation of MR by Dex or 11-ketoDex was weak or undetectable, despite efficient binding and induction of nuclear translocation. 11beta-HSD2 protects MR and GR from inappropriate occupation by cortisol; it is, however, unable to prevent activation of GR by 11-ketoDex. The finding that 11-ketoDex is a specific GR agonist may explain the potent glucocorticoid effect of Dex in tissues expressing 11beta-HSD2 including kidney and colon and also in certain tumor cells.

11β-Hydroxysteroid dehydrogenase type 2 is selectively expressed in aldosterone target tissues, where it confers aldosterone selectivity for the mineralocorticoid receptor by inactivating 11β-hydroxyglucocorticoids with a high affinity for the mineralocorticoid receptor. The present investigation aimed to elucidate the mechanisms accounting for the rigorous control of theHSD11B2 gene in humans. Using dimethyl sulfatein vivo footprinting via ligation-mediated PCR, we identified potentially important regions for HSD11B2regulation in human cell lines: two GC-rich regions in the first exon (I and II) and two upstream elements (III and IV). The footprints suggest a correlation between the extent of in vivo protein occupancy at three of these regions (I, II, and III) and the rate ofHSD11B2 transcription in cells with high (SW620), intermediate (HCD, MCF-7, and HK-2), or low HSD11B2mRNA levels (SUT). Moreover, gel shift assays with nuclear extracts from these cell lines revealed that decreased HSD11B2expression is related to a decreased binding activity with oligonucleotides containing the putative regulatory elements. Antibody supershifts identified the majority of the components of the binding complexes as the transcription factors Sp1 and Sp3. Finally, transient transfections with various deletion mutant reporters define positive regulatory elements that might account for basal and selective expression of 11β-hydroxysteroid dehydrogenase type 2.

Phosphodiesterase 10A (PDE10A) is a novel therapeutic target for the treatment of schizophrenia. Here we report a novel role of PDE10A in the regulation of caloric intake and energy homeostasis. PDE10A-deficient mice are resistant to diet-induced obesity (DIO) and associated metabolic disturbances. Inhibition of weight gain is due to hypophagia after mice are fed a highly palatable diet rich in fats and sugar but not a standard diet. PDE10A deficiency produces a decrease in caloric intake without affecting meal frequency, daytime versus nighttime feeding behavior, or locomotor activity. We tested THPP-6, a small molecule PDE10A inhibitor, in DIO mice. THPP-6 treatment resulted in decreased food intake, body weight loss, and reduced adiposity at doses that produced antipsychotic efficacy in behavioral models. We show that PDE10A inhibition increased whole-body energy expenditure in DIO mice fed a Western-style diet, achieving weight loss and reducing adiposity beyond the extent seen with food restriction alone. Therefore, chronic THPP-6 treatment conferred improved insulin sensitivity and reversed hyperinsulinemia. These data demonstrate that PDE10A inhibition represents a novel antipsychotic target that may have additional metabolic benefits over current medications for schizophrenia by suppressing food intake, alleviating weight gain, and reducing the risk for the development of diabetes.

We previously introduced a method called steroid-mediated gene delivery (SMGD), which uses steroid receptors as shuttles to facilitate the nuclear uptake of transfected DNA. Here, we describe a SMGD strategy with peptide nucleic acids (PNAs) that allowed linkage of a steroid molecule to a defined position in a plasmid without disturbing its gene expression. We synthesized and tested several bifunctional steroid derivatives [patent in process of nationalization] and finally selected the compound named DEX-bisPNA, a molecule consisting of a dexamethasone moiety linked to a PNA clamp (bisPNA) through a 30-atom chemical spacer. Dex-bisPNA binds to the glucocorticoid receptor (GR) as well as to reporter plasmids containing the corresponding PNA binding sites, translocates the GR from the cytoplasm into the nucleus, and increases the delivery of plasmid to the nucleus, resulting in enhanced GR-dependent expression of the reporter gene. The SMGD effect was more pronounced in growth-arrested cells than in proliferating cells. The specificity for the GR was shown by the reversion of the SMGD effect in the presence of dexamethasone as well as an enhanced expression in GR-positive cells but not in GR-negative cells. Thus, SMGD with PNA is a promising strategy for nonviral gene delivery into target tissues expressing specific steroid receptors.

Neuromedin U (NMU) is a highly conserved peptide reported to modulate energy homeostasis. Pharmacological studies have shown that centrally administered NMU inhibits food intake, reduces body weight, and increases energy expenditure. NMU-deficient mice develop obesity, whereas transgenic mice overexpressing NMU become lean and hypophagic. Two high-affinity NMU receptors, NMUR1 and NMUR2, have been identified. NMUR1 is found primarily in the periphery and NMUR2 primarily in the brain, where it mediates the anorectic effects of centrally administered NMU. Given the broad expression pattern of NMU, we evaluated whether peripheral administration of NMU has effects on energy homeostasis. We observed that acute and chronic peripheral administration of NMU in rodents dose-dependently reduced food intake and body weight and that these effects required NMUR1. The anorectic effects of NMU appeared to be partly mediated by vagal afferents. NMU treatment also increased core body temperature and metabolic rate in mice, suggesting that peripheral NMU modulates energy expenditure. Additionally, peripheral administration of NMU significantly improved glucose excursion. Collectively, these data suggest that NMU functions as a peripheral regulator of energy and glucose homeostasis and the development of NMUR1 agonists may be an effective treatment for diabetes and obesity.

Objective— Adiponectin is an adipocyte-derived, secreted protein that is implicated in protection against a cluster of related metabolic disorders. Mice lacking adiponectin display impaired hepatic insulin sensitivity and respond only partially to peroxisome proliferator-activated receptor γ agonists. Adiponectin has been associated with antiinflammatory and antiatherogenic properties; however, the direct involvement of adiponectin on the atherogenic process has not been studied. Methods and Results— We crossed adiponectin knockout mice ( Adn −/− ) or mice with chronically elevated adiponectin levels ( Adn Tg ) into the low-density lipoprotein receptor–null ( Ldlr −/− ) and the apoliprotein E–null ( Apoe −/− ) mouse models. Adiponectin levels did not correlate with a suppression of the atherogenic process. Plaque volume in the aortic root, cholesterol accumulation in the aorta, and plaque morphology under various dietary conditions were not affected by circulating adiponectin levels. In light of the strong associations reported for adiponectin with cardiovascular disease in humans, the lack of a phenotype in gain- and loss-of-function studies in mice suggests a lack of causation for adiponectin in inhibiting the buildup of atherosclerotic lesions. Conclusion— These data indicate that the actions of adiponectin on the cardiovascular system are complex and multifaceted, with a minimal direct impact on atherosclerotic plaque formation in preclinical rodent models.

The enzyme 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) catalyzes the conversion of inactive to active glucocorticoids. 11beta-HSD1 plays a crucial role in the pathogenesis of obesity and controls glucocorticoid actions in inflammation. Several studies have demonstrated that TNF-alpha increases 11beta-HSD1 mRNA and activity in various cell models. Here, we demonstrate that mRNA and activity of 11beta-HSD1 is increased in liver tissue from transgenic mice overexpressing TNF-alpha, indicating that this effect also occurs in vivo. To dissect the molecular mechanism of this increase, we investigated basal and TNF-alpha-induced transcription of the 11beta-HSD1 gene (HSD11B1) in HepG2 cells. We found that TNF-alpha acts via p38 MAPK pathway. Transient transfections with variable lengths of human HSD11B1 promoter revealed highest activity with or without TNF-alpha in the proximal promoter region (-180 to +74). Cotransfection with human CCAAT/enhancer binding protein-alpha (C/EBPalpha) and C/EBPbeta-LAP expression vectors activated the HSD11B1 promoter with the strongest effect within the same region. Gel shift and RNA interference assays revealed the involvement of mainly C/EBPalpha, but also C/EBPbeta, in basal and only of C/EBPbeta in the TNF-alpha-induced HSD11B1 expression. Chromatin immunoprecipitation assay confirmed in vivo the increased abundance of C/EBPbeta on the proximal HSD11B1 promoter upon TNF-alpha treatment. In conclusion, C/EBPalpha and C/EBPbeta control basal transcription, and TNF-alpha upregulates 11beta-HSD1, most likely by p38 MAPK-mediated increased binding of C/EBPbeta to the human HSD11B1 promoter. To our knowledge, this is the first study showing involvement of p38 MAPK in the TNF-alpha-mediated 11beta-HSD1 regulation, and that TNF-alpha stimulates enzyme activity in vivo.

The adipose tissue-derived hormone adiponectin improves insulin sensitivity and its circulating levels are decreased in obesity-induced insulin resistance. Here, we report the generation of a mouse line with a genomic disruption of the adiponectin locus. We aimed to identify whether these mice develop insulin resistance and which are the primary target tissues affected in this model. Using euglycemic/insulin clamp studies, we demonstrate that these mice display severe hepatic but not peripheral insulin resistance. Furthermore, we wanted to test whether the lack of adiponectin magnifies the impairments of glucose homeostasis in the context of a dietary challenge. When exposed to high fat diet, adiponectin null mice rapidly develop glucose intolerance. Specific PPARgamma agonists such as thiazolidinediones (TZDs) improve insulin sensitivity by mechanisms largely unknown. Circulating adiponectin levels are significantly up-regulated in vivo upon activation of PPARgamma. Both TZDs and adiponectin have been shown to activate AMP-activated protein kinase (AMPK) in the same target tissues. We wanted to address whether the ability of TZDs to improve glucose tolerance is dependent on adiponectin and whether this improvement involved AMPK activation. We demonstrate that the ability of PPARgamma agonists to improve glucose tolerance in ob/ob mice lacking adiponectin is diminished. Adiponectin is required for the activation of AMPK upon TZD administration in both liver and muscle. In summary, adiponectin is an important contributor to PPARgamma-mediated improvements in glucose tolerance through mechanisms that involve the activation of the AMPK pathway.

Author(s): Jurgens, Hella; Haass, Wiltrud; Castaneda, Tamara R; Schurmann, Annette; Koebnick, Corinna; Dombrowski, Frank; Otto, Barbel; Nawrocki, Andrea R; Scherer, Philipp E; Spranger, Jochen; Ristow, Michael; Joost, Hans-Georg; Havel, Peter J; Tschop, Matthias H | Abstract: ObjectiveThe marked increase in the prevalence of obesity in the United States has recently been attributed to the increased fructose consumption. To determine if and how fructose might promote obesity in an animal model, we measured body composition, energy intake, energy expenditure, substrate oxidation, and several endocrine parameters related to energy homeostasis in mice consuming fructose.Research methods and proceduresWe compared the effects of ad libitum access to fructose (15% solution in water), sucrose (10%, popular soft drink), and artificial sweetener (0% calories, popular diet soft drink) on adipogenesis and energy metabolism in mice.ResultsExposure to fructose water increased adiposity, whereas increased fat mass after consumption of soft drinks or diet soft drinks did not reach statistical significance (n = 9 each group). Total intake of energy was unaltered, because mice proportionally reduced their caloric intake from chow. There was a trend toward reduced energy expenditure and increased respiratory quotient, albeit not significant, in the fructose group. Furthermore, fructose produced a hepatic lipid accumulation with a characteristic pericentral pattern.DiscussionThese data are compatible with the conclusion that a high intake of fructose selectively enhances adipogenesis, possibly through a shift of substrate use to lipogenesis.

The 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2) regulates access of 11beta-hydroxyglucocorticoids to the mineralocorticoid receptor by reducing the hydroxyl group of these steroids at position 11. Previous cell culture studies revealed that tumor necrosis factor-alpha (TNF-alpha) down-regulates 11beta-HSD2 activity. Here, we demonstrate that transgenic mice overexpressing TNF-alpha have decreased mRNA abundance and activity of 11beta-HSD2 in kidney tissue, indicating that this effect may occur also in vivo. The analysis of the transcriptional regulation of 11beta-HSD2 by TNF-alpha and phorbol 12-myristate-13-acetate (PMA) with in vivo genomic footprinting in human colon SW620 cells revealed stimulus-dependent protein-DNA interactions in three promoter regions, kappaB1, Sp1/Egr-1I, and Sp1/Egr-1II. Chromatin immunoprecipitation and electrophoretic mobility shift assays demonstrated the relevance of NF-kappaB binding to kappaB1 and of Egr-1 binding to Sp1/Egr-1 sites for the PMA and TNF-alpha effect. We observed a temporal switch of binding to kappaB1 site from active p65/p50 heterodimers to inactive p50/p50 homodimers. TNF-alpha or PMA treatment for 24 h resulted in accumulation of p50 and decrease of p65 nuclear proteins. Overexpression of p50 inhibited HSD11B2 promoter activity and overexpression of Egr-1 inhibited transactivation of the HSD11B2 promoter by p65/p50. In conclusion, TNF-alpha and PMA down-regulate expression and activity of 11beta-HSD2 most likely by a coordinate binding of p50/p50 and Egr-1 to the HSD11B2 promoter.

Adipose tissue has evolved as a complex organ with functions far beyond the mere storage of energy. Chronic oversupply of calories, common to Western-style diets, frequently goes hand-in-hand with an altered secretion pattern of adipokines and elevated plasma free fatty acid levels, known to modulate insulin sensitivity in skeletal muscle. Intramyocellular accumulation of lipids directly attenuates insulin signaling within myocytes via distinct kinases. Obesity is also accompanied by an enhanced basal inflammatory tone, originating from adipocytes and adipose tissue-associated macrophages. In addition, adipocytes accumulate within the skeletal muscle and exert direct paracrine effects on muscle insulin sensitivity.

Adiponectin is a plasma protein expressed exclusively in adipose tissue. Adiponectin levels are linked to insulin sensitivity, but a direct effect of chronically elevated adiponectin on improved insulin sensitivity has not yet been demonstrated. We identified a dominant mutation in the collagenous domain of adiponectin that elevated circulating adiponectin values in mice by 3-fold. Adiponectinemia raised lipid clearance and lipoprotein lipase activity, and suppressed insulin-mediated endogenous glucose production. The induction of adiponectin during puberty and the sexual dimorphism in adult adiponectin values were preserved in these transgenic animals. As a result of elevated adiponectin, serum PRL values and brown adipose mass both increased. The effects on carbohydrate and lipid metabolism were associated with elevated phosphorylation of 5'-AMP-activated protein kinase in liver and elevated expression of peroxisomal proliferator-activated receptor gamma2, caveolin-1, and mitochondrial markers in white adipose tissue. These studies strongly suggest that increasing endogenous adiponectin levels has direct effects on insulin sensitivity and may induce similar physiological responses as prolonged treatment with peroxisomal proliferator-activated receptor gamma agonists.

11beta-Hydroxysteroid dehydrogenase type 2 is selectively expressed in aldosterone target tissues, where it confers aldosterone selectivity for the mineralocorticoid receptor by inactivating 11beta-hydroxyglucocorticoids with a high affinity for the mineralocorticoid receptor. The present investigation aimed to elucidate the mechanisms accounting for the rigorous control of the HSD11B2 gene in humans. Using dimethyl sulfate in vivo footprinting via ligation-mediated PCR, we identified potentially important regions for HSD11B2 regulation in human cell lines: two GC-rich regions in the first exon (I and II) and two upstream elements (III and IV). The footprints suggest a correlation between the extent of in vivo protein occupancy at three of these regions (I, II, and III) and the rate of HSD11B2 transcription in cells with high (SW620), intermediate (HCD, MCF-7, and HK-2), or low HSD11B2 mRNA levels (SUT). Moreover, gel shift assays with nuclear extracts from these cell lines revealed that decreased HSD11B2 expression is related to a decreased binding activity with oligonucleotides containing the putative regulatory elements. Antibody supershifts identified the majority of the components of the binding complexes as the transcription factors Sp1 and Sp3. Finally, transient transfections with various deletion mutant reporters define positive regulatory elements that might account for basal and selective expression of 11beta-hydroxysteroid dehydrogenase type 2.

Background & Aims: 11β-Hydroxysteroid dehydrogenase (11β-OHSD) enzymes are responsible for the interconversion of active 11β-hydroxycorticosteroids into inactive 11-ketoglucocorticosteroids and by that mechanism regulate the intracellular access of the steroids to the cognate receptor. A down-regulation of the shuttle of active to inactive glucocorticoids enhances access of glucocorticosteroids to both the glucocorticoid and the mineralocorticoid receptors. In liver cirrhosis, enhanced mineralocorticoid and glucocorticoid effects are observed. We therefore investigated the impact of liver cirrhosis after bile duct ligation on the transcription and activity of 11β-OHSD1 and 11β-OHSD2 in the corresponding tissues. Methods: Messenger RNA from 11β-OHSD1 and 11β-OHSD2 was assessed by reverse-transcription polymerase chain reaction; activity was assessed by measuring the interconversion of corticosterone to dehydrocorticosterone. The effect of bile and bile salts was determined using COS-1 cells transfected with 11β-OHSD1 or 11β-OHSD2. Results: In liver tissue, the messenger RNA ratios of 11β-OHSD1 to glyceraldehyde-3-phosphate dehydrogenase (GAPDH) levels and, in kidney tissue, the ratios of 11β-OHSD2 to GAPDH levels decreased after induction of liver cirrhosis. The 11β-OHSD activities were correspondingly reduced. Bile and individual bile salts inhibited 11β-OHSD1 and 11β-OHSD2 oxidative activity in transfected COS-1 cells. Conclusions: These findings indicate that in liver cirrhosis the mineralocorticoid and glucocorticoid receptor–protecting effects by the 11β-OHSD isoenzymes are down-regulated and that by the same mechanism the glucocorticoid and mineralocorticoid effects are enhanced. GASTROENTEROLOGY 1998;114:175-184

Short-chain fatty acids (SCFAs), primarily acetate, propionate, and butyrate, are metabolites formed by gut microbiota from complex dietary carbohydrates. Butyrate and acetate were reported to protect against diet-induced obesity without causing hypophagia, while propionate was shown to reduce food intake. However, the underlying mechanisms for these effects are unclear. It was suggested that SCFAs may regulate gut hormones via their endogenous receptors Free fatty acid receptors 2 (FFAR2) and 3 (FFAR3), but direct evidence is lacking. We examined the effects of SCFA administration in mice, and show that butyrate, propionate, and acetate all protected against diet-induced obesity and insulin resistance. Butyrate and propionate, but not acetate, induce gut hormones and reduce food intake. As FFAR3 is the common receptor activated by butyrate and propionate, we examined these effects in FFAR3-deficient mice. The effects of butyrate and propionate on body weight and food intake are independent of FFAR3. In addition, FFAR3 plays a minor role in butyrate stimulation of Glucagon-like peptide-1, and is not required for butyrate- and propionate-dependent induction of Glucose-dependent insulinotropic peptide. Finally, FFAR3-deficient mice show normal body weight and glucose homeostasis. Stimulation of gut hormones and food intake inhibition by butyrate and propionate may represent a novel mechanism by which gut microbiota regulates host metabolism. These effects are largely intact in FFAR3-deficient mice, indicating additional mediators are required for these beneficial effects.