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Objective The aim of the study was to investigate whether inhibition of Sonic Hedgehog (SHH) pathway would prevent progression of Barrett's Esophagus (BE) to esophageal adenocarcinoma. Background The hedgehog signaling pathway is a leading candidate as a molecular mediator of BE and esophageal adenocarcinoma (EAC). Repurposed use of existing off-patent, safe and tolerable drugs that can inhibit hedgehog, such as itraconazole, could prevent progression of BE to EAC. Methods The efficacy of itraconazole was investigated using a surgical rat reflux model of Barrett's Metaplasia (BM). Weekly intraperitoneal injections of saline (control group) or itraconazole (treatment group; 200 mg/kg) were started at 24 weeks postsurgery. Esophageal tissue was harvested at 40 weeks. The role of the Hh pathway was also evaluated clinically. Esophageal tissue was harvested after 40 weeks for pathological examination and evaluation of the SHH pathway by immunohistochemistry. Results BM was present in control animals 29 of 31 (93%) versus itraconazole 22 of 24 (91%). EAC was significantly lower in itraconazole 2 of 24 (8%) versus control 10 of 31 (32%), respectively (P = 0.033). Esophageal SHH levels were lower in itraconazole vs control (P = 0.12). In esophageal tissue from humans with recurrent or persistent dysplastic BE within 24 months of ablative treatment, strong SHH and Indian Hedgehog expression occurred in distal BE versus proximal squamous epithelium, odds ratio = 6.1 (95% confidence interval: 1.6, 23.4) and odds ratio = 6.4 (95% confidence interval: 1.2, 32.8), respectively. Conclusion Itraconazole significantly decreases EAC development and SHH expression in a preclinical animal model of BM. In humans, BE tissue expresses higher SHH, Indian Hedgehog, and bone morphogenic protein levels than normal squamous esophageal epithelium.

Background Measuring expression profiles of inflammatory biomarkers is important in monitoring the polarization of immune responses; therefore, results should be independent of quantitation methods if they are to be accepted as validated clinical pathology biomarkers. To evaluate effects of differing quantitation methods, the seven major circulating Th1/Th2/Th17 cytokines interleukin 2 (IL-2), interferon γ (IFN-γ), tumor necrosis factor α (TNF-α), IL-4, IL-6, IL-10 and IL-17A were quantified in plasma of lipopolysaccharide (LPS)-treated mice with two different multiplex platforms. Methods Female C57BL6 mice were treated orally with vehicle or dexamethasone, followed by LPS intravenously. Plasma samples were analyzed 0.5, 1, 2, 4, and 6 h post-LPS challenge with assays at Myriad-RBM and compared to assays performed on a BD Accuri C6 flow cytometer. Results IL-17A response to LPS was limited but sustained, and the response for the remaining cytokines were early and transient; dexamethasone reduced expression of all 7 cytokines. TNF-α and IL-6 levels were similar across both assays, and IL-4 levels were generally very low. Plasma levels of remaining cytokines were variably lower with BD assays than Myriad-RBM assays. Conclusions The present findings demonstrate that quantitation of circulating biomarkers of inflammation can be achieved using multiplexed flow cytometry, but careful consideration must be taken for assay validation when cross-referencing with another multiplexed assay.

Aim: Oral and intravenous pharmacokinetic (PK) studies were conducted in four different minipig strains: Sinclair, Yucatan, Hanford and Göttingen after administration of metformin or R,S-verapamil (R,S-VER). Results: The results indicated that the PK of metformin was similar between all minipig strains, except for the Göttingen which had higher plasma clearance. The plasma clearance of both (+)-(R)- and (−)-(S)-VER was significantly lower in Sinclair compared with the clearance in other strains. The (+)-(R)-NOR to R,S-VER ratio was significantly higher in the Sinclair. There was a preferential conversion of R,S-VER to (+)-(R)-NOR over (−)-(S)-NOR in all minipig strains. Conclusion: This work highlights the importance of considering the impact of metabolic and dispositional differences in minipig strains when conducting PK studies.

A functional observational battery (FOB) is recommended as the first-tier neurotoxicity screening in the preclinical safety pharmacology testing guidelines. Minipigs have increasingly been used in regulatory toxicology studies; however, no current FOB protocol is available for neurotoxicity testing in these species. Hence, a minipig FOB instrument was developed. A complete crossover study with Sinclair minipigs was performed to evaluate physiologic, neurologic, and behavioral effects of amphetamine, ketamine, and diazepam. The treated minipigs were first observed in their home cage, were video-recorded for 10 minutes in an open field, and then went through a complete neurologic examination. Both ketamine and diazepam were shown to reduce the freezing and behavior shifts of treated minipigs, while increasing their exploratory behaviors. Both drugs also caused muscular and gait impairment. The effects of ketamine and diazepam were consistent with their roles as central nervous system (CNS) suppressants. Unique effects were also observed with ketamine and diazepam treatments, which may reflect their unique mechanisms of action. Consistent with its role as a CNS stimulant, amphetamine caused the treated minipigs to be hyperactive and to display increased freezing and behavior shifts and reduced exploring activities. These effects of amphetamine were opposite to those observed with ketamine and diazepam. Amphetamine also increased locomotion in the treated minipigs. The present effects of amphetamine, ketamine, and diazepam are in agreement with observations by others. In conclusion, the minipig is a suitable species for FOB evaluation of pharmaceuticals in preclinical safety pharmacology testing.

The use of the miniature swine as a nonrodent species in research has continued to expand for over a decade, and they are becoming routinely used both in experimental pharmacology and as a therapeutic model for human diseases. Miniature swine models are regularly used for studies designed to assess efficacy and safety of new therapeutic compounds given through different routes of exposure and are used as an alternative model to rodents, canines, or nonhuman primates. Translational preclinical swine study data presented here support the current understanding that miniature swine are the animal model of choice for the assessment of drugs targeting endocrine, dermal, and ocular disorders. Because research investigators need to be familiar with some of the important features of the models developed in the miniature swine in order to place clinical and experimental findings in their proper perspective, relevant references and data from these models will be presented, compared, and partially illustrated.

The minipig has become a popular animal model in biomedical research. Minipigs offer advantages over domestic pigs due to their size and ease of handling, and offer a viable alternative to canine and non-human primates as a large animal model in the assessment of safety and toxicology of pharmaceutical compounds. Minipigs have similar anatomical and physiological features relative to humans, especially in regards to the gastrointestinal system. Despite the similarities to humans, minipigs also have key differences that should be considered in a research setting, discussed in this chapter. Furthermore, there are many available breeds of minipigs, and variations in breeds should be considered when working with minipigs in biomedical research. This chapter discusses the anatomy and physiology of the pig’s digestive system, as well as its use in surgical and efficacy research, pharmacology, and toxicology. It also discusses differences in absorption, and incidental toxicology findings in commonly used breeds of minipigs: Sinclair, Hanford, Yucatan, and Gottingen.

Abundant evidence shows that patients with type 1 diabetes are at high risk for several cardiovascular disorders. Our objective was to assess cardiac electro-pathophysiology changes linked to chronic insulin-dependent diabetes in the Yucatan miniature swine (total N = 22). Diabetic animals were divided into different groups based on duration of diabetes (Group 1: normal; Groups 2, 3, 4 and 5: diabetes duration of 3-4, 4-5, 5-6 and >6 years). Cardiac electrophysiological parameters were acquired in conscious diabetic and normal control animals using a standard lead II configuration. Routine measurements of electrocardiograms, including HR (bpm), RR, PR, QRS, QT and QTc, were done (all in msec). A heart rate correction for the QT interval (QTc) was calculated using the Fridericia method [QTc=QT/(cubed root of RR)]. Mean heart rate was decreased for the diabetic Groups 2, 4, and 5 compared to the mean heart rate for normal animals (52, 54 and 54 vs. 75 bpm, respectively). The mean PR interval was increased in all diabetic animals compared to normal animals and the effect increase with the duration of diabetes (132 vs. 138, 140, 152 and 172 msec for Groups 1, 2, 3, 4 and 5, respectively). The mean QRS interval was increased for all of the diabetic animals compared to normal animals (47 vs. 56, 66, 52 and 64 msec for Groups 1, 2, 3, 4 and 5, respectively). There were no pronounced QTc abnormalities in this study when comparing diabetic to the normal animals although one animal in Group 3 did have a QTc prolongation of 43 msec. In addition, one animal in Group 5 had a prolonged PR segment (224 msec) associated with frequent ventricular escape complexes. In conclusion, chronic diabetes in Yucatan miniature swine manifests with progressive effects on heart rate, PR interval, and QRS duration. This indicates that the diabetic minipig could provide a good model to test preventative approaches for progressive cardiac therapies in diabetes, using electrocardiography segments as markers of early heart damage. Disclosure A. Stricker-Krongrad: None. J. Liu: None. G. Bouchard: None.

Introduction: Excessive bleeding is a complication of wound debridement in patients receiving anticoagulation treatment. Chitosan is a linear, positively charged polysaccharide that has potential as a hemostatic topical dressing. This study examined the hemostatic efficacy of the chitosan based Opticell dressing (Medline Industries, Chicago, Ill) in heparinized rats with excisional wounds mimicking debridement. Methods: Three paired 12-mm excisional wounds were created on the dorsum of 600-g Sprague-Dawley rats 2 hours after intraperitoneal injection of heparin 800 IU/kg. Opticell or gauze dressings were applied with 3 seconds of gentle pressure. Results: Total Bleeding: The dressings were left in place until cessation of bleeding. Ten minutes was enough time for complete bleeding cessation in both groups. Gauze and Opticell were weighed before and after bleeding cessation, with the difference representing blood loss. Total blood loss was 627 ± 47 mg/10 min with the standard gauze, but 247 ± 47 mg/10 min with Opticell (P = .002 Mann-Whitney). N = 6 wounds per group. Rate of Bleeding: Gauze and Opticell dressings were removed and instantly replaced with 3 seconds of gentle pressure every minute until bleeding cessation. The removed dressings were weighed before and after application. There was less bleeding in the Opticell group at minutes 1, 2, and 3. Gauze: 183 ± 40, 140 ± 30, and 109 ± 15 mg/min vs Opticell: 91 ± 17, 54 ± 8, and 57 ± 11 mg/min). Analysis of variance, Tukey's test, P < .05. N = 12 wounds per group. Conclusion: Topical application of Opticell dressing with chitosan has hemostatic effects that could be a useful tool to control bleeding associated with wound debridement.

The use of miniature swine as a nonrodent species in safety assessment has continued to expand for over a decade, and they are becoming routinely used in toxicology and in pharmacology as well as a model for human diseases. Miniature swine models are regularly used for regulatory toxicity studies designed to assess safety of new therapeutic compounds given through different routes of exposure and are used as an alternative model to the canine or the nonhuman primate. Translational preclinical swine study data presented support the current finding that miniature swine are the animal model of choice for assessment of drug absorption, tolerance, and systemic toxicity following systemic exposures. Because research investigators need to be familiar with important anatomic and histopathologic features of the miniature swine in order to place toxicopathologic findings in their proper perspective, clinical and anatomic pathology data from a large number of Sinclair, Hanford, Yucatan, and Göttingen breeds from control groups from a wide variety of studies performed between 2004 and 2014 will be presented, compared, and partially illustrated.

The minipig has been increasingly recognized as a valid alternative to canines and nonhuman primates in regulatory toxicity. This article presents the results of cardiovascular assessments in the Yucatan, Hanford, Sinclair, and Göttingen minipigs conducted during nonclinical investigations and control toxicity testing. Cardiac electrophysiology was obtained using clinical electrocardiogram and surgical monitor units. Peripheral vessel diameter, velocity, and flow were obtained by Doppler ultrasonography, and cardiac vessel diameter was obtained postmortem. Anatomic parameters were obtained at necropsy. Histopathology assessments were conducted on heart, blood vessels, and kidneys. Collected data were compared to published cardiovascular measurements of adult humans to illustrate similarities and differences. Each lineage of minipigs was found to have specific anatomic and physiologic characteristics that may accurately reflect response of human cardiovascular systems in clinical investigations and toxicity testing. In conclusion, the interspecies similarities between the cardiovascular systems make these lineages of minipigs suitable as models for the human counterpart. In addition, these reported differences between lineages will aid investigators in selecting a relevant lineage of minipigs if specific cardiovascular parameters are required during drug safety evaluation.

CRTh2 (DP2) is a prostaglandin D2 receptor implicated in the recruitment of eosinophils and basophils within the asthmatic lung. Here we report the discovery of a novel series of 3-indolyl sultam antagonists with low nM affinity for CRTh2. These compounds proved to be selective over the other primary prostaglandin D2 receptor (DP1) as well as the thromboxane A2 receptor (TP).

e13552Background: Up-regulated progenitor cell proliferation induced by abnormal activation of the hedgehog (HH) signaling pathway contributes to carcinogenesis in the esophagus and HH is considere...

Formulation of nonclinical evaluations is a challenge, with the fundamental need to achieve multiples of the clinical exposure complicated by differences in species and routes of administration-specific tolerances, depending on concentrations, volumes, dosing regimen, duration of each administration, and study duration. Current practice to approach these differences is based on individual experience and scattered literature with no comprehensive data source (the most notable exception being our 2006 publication on this same subject). Lack of formulation tolerance data results in excessive animal use, unplanned delays in the evaluation and development of drugs, and vehicle-dependent results. A consulting firm, a chemical company, and 4 contract research organizations conducted a rigorous data mining operation of vehicle data from studies dating from 1991 to 2015, enhancing the data from this author’s 2006 publication (3 of the six 2015 contributors were also 2006 contributors). Additional data were found in the published literature. The results identified 108 single-component vehicles (and 305 combination formulations) used in more than 1,040 studies across multiple species (dog, primate, rat, mouse, rabbit, guinea pig, minipig, pig, chick embryo, and cat) by multiple routes for a wide range of study durations. The tabulated data include maximum tolerated use levels by species, route, duration of study, dose-limiting toxicity where reported, review of the available literature on each vehicle, guidance on syringe selection, volume and pH limits by route with basic guidance on nonclinical formulation development, and guidance on factors to be considered in nonclinical route selection.