A straightforward guide to the swine left upper lobar transplant model: procedures and techniques

With the rising demand for lung transplants, especially for adults with smaller chest cavities and children, a significant donor-recipient size mismatch challenge exists. A solution is lobar lung transplants from deceased donors with otherwise unsuitable lungs due to local damage. Despite its promise, early post-transplant mortality rates are comparatively high, emphasizing the need for meticulous donor selection and graft evaluation. This video tutorial introduces a detailed methodology for a porcine left upper lobar lung transplant model, from preoperative measures to reperfusion. Steps encompass preoperative measures, donor and recipient preparations, graft procurement and specific anastomosis procedures for the bronchus, pulmonary artery and left atrium. This guidance, derived from rigorous translational research, not only contributes to the knowledge of safe lobar lung transplants in animals but also promises potential implications for clinical practice.

Playback of rat 22-kHz ultrasonic vocalizations as a translational assay of negative affective states: An analysis of evoked behavior and brain activity

The subjective nature of human emotions makes them uniquely challenging to investigate in preclinical models. While behavioral assays in rodents aim to evaluate affect (i.e., anxiety, hypervigilance), they often lack ethological validity. Playback of negatively valenced 22-kHz ultrasonic vocalizations (USVs) in rats shows promise as a translational tool to investigate affective processing. Much like how human facial expressions can communicate internal states, rats emit 22-kHz USVs that similarly convey negative affective states to conspecifics indicating possible threat. 22-kHz USV playback elicits avoidance and hypervigilant behaviors, and recruit brain regions comparable to those seen in human brains evoked by viewing fearful faces. Indeed, 22-kHz playback alters neural activity in brain regions associated with negative valence systems (i.e., amygdala, bed nucleus of the stria terminalis, periaqueductal gray) alongside increases in behaviors typically associated with anxiety. Here, we present evidence from the literature that supports leveraging 22-kHz USV playback in rat preclinical models to obtain clinically relevant and translational findings to identify the neural underpinnings of affective processing and neuropathological dysfunction.

Commentary: Improving the Effectiveness and Utility of the Helping to End Addiction Long-Term (HEAL) Prevention Cooperative: A Full Translational Framework

The Helping to End Addiction Long-term (HEAL) Prevention Collaborative (HPC) is designed to expedite the development of programs aimed at preventing opioid misuse and opioid use disorder (OUD) in older adolescents and young adults (ages 16-30). Funded by the National Institutes of Health Office of the Director (ODP-NIH), the HPC includes ten outcome studies that focus on distinct interventions to determine their effectiveness and real-world applicability. Also included is a coordinating center at RTI International that supports the individual projects. This commentary highlights the scientific and practical significance of this cooperative and its promise for facilitating the production and implementation of successful interventions. Attributes such as novel program designs, advanced methodologies, addressing unique characteristics of diverse populations, and real-time analysis of data and costs make this cooperative highly innovative. We note, however, that papers in this Supplemental Issue did not specifically address the persistent need to obtain stronger effect sizes than those achieved to date. Existing data captured earlier in development (< 16 years of age) are uncovering interactive neurocognitive and social-contextual mechanisms underlying the phenomena we wish to prevent. HPC projects could be guided by this information to incorporate developmentally appropriate measures of mechanisms shown previously to be influential in targeted outcomes and determine how they are impacted by specific components of their interventions. This mechanistic information can provide a roadmap for constructing interventions that are more precision-based and, thus, more likely to yield greater benefits for a larger number of recipients. Furthermore, an understanding of underlying mechanism(s) promises to shed light on the sources of heterogeneity in outcomes for further intervention refinement. It is quite possible, if not probable, that meaningful measures of underlying processes will reveal subtypes-some with very high effect sizes and others that are much lower-directly enabling program refinements to more directly target mechanisms that portend and explain less favorable outcomes. Described herein is a full-spectrum translational approach which promises to significantly boost effect sizes, a key objective that should be reached prior to scaling.

Age-associated changes in electroretinography measures in companion dogs

PURPOSE

To determine the association between age and retinal full-field electroretinographic (ERG) measures in companion (pet) dogs, an important translational model species for human neurologic aging.

METHODS

Healthy adult dogs with no significant ophthalmic abnormalities were included. Unilateral full-field light- and dark-adapted electroretinography was performed using a handheld device, with mydriasis and topical anaesthesia. Partial least squares effect screening analysis was performed to determine the effect of age, sex, body weight and use of anxiolytic medication on log-transformed ERG peak times and amplitudes; age and anxiolytic usage had significant effects on multiple ERG outcomes. Mixed model analysis was performed on data from dogs not receiving anxiolytic medications.

RESULTS

In dogs not receiving anxiolytics, median age was 118 months (interquartile range 72-140 months, n = 77, 44 purebred, 33 mixed breed dogs). Age was significantly associated with prolonged peak times of a-waves (dark-adapted 3 and 10 cds/m² flash p < 0.0001) and b-waves (cone flicker p = 0.03, dark-adapted 0.01 cds/m² flash p = 0.001). Age was also significantly associated with reduced amplitudes of a-waves (dark-adapted 3 cds/m² flash p < 0.0001, 10 cds/m² flash p = 0.005) and b-waves (light-adapted 3 cds/m² flash p < 0.0001, dark-adapted 0.01 cds/m² flash p = 0.0004, 3 cds/m² flash p < 0.0001, 10 cds/m² flash p = 0.007) and flicker (light-adapted 30 Hz 3 cds/m² p = 0.0004). Within the Golden Retriever breed, these trends were matched in a cross-sectional analysis of 6 individuals that received no anxiolytic medication.

CONCLUSIONS

Aged companion dogs have slower and reduced amplitude responses in both rod- and cone-mediated ERG. Consideration of anxiolytic medication use should be made when conducting ERG studies in dogs.

Hepatoprotective effects of the long-acting FGF21 analogue PF-05231023 in the GAN diet-induced obese and biopsy-confirmed mouse model of NASH

Fibroblast growth factor 21 (FGF21) plays a key role in hepatic lipid metabolism and long-acting FGF21 analogues has emerged as a promising drug candidates for the treatment of non-alcoholic steatohepatitis (NASH). It remains to characterize this drug class in translational animal models that recapitulate the aetiology and hallmarks of the human disease. To this end, we evaluated the long-acting FGF21 analogue PF-05231023 in the GAN (Gubra Amylin NASH) diet-induced obese (DIO) and biopsy-confirmed mouse model of NASH. Male C57BL/6J mice were fed the GAN diet high in fat, fructose, and cholesterol for 34 weeks prior to study start. GAN DIO-NASH mice with biopsy-confirmed NAFLD Activity Score (NAS ≥5) and fibrosis (stage ≥F1) were biweekly administered with PF-05231023 (10 mg/kg, SC) or vehicle (SC) for 12 weeks. Vehicle-dosed chow-fed C57BL/6J mice served as healthy controls. Pre-to-post liver biopsy histopathological scoring was performed for within-subject evaluation of NAFLD Activity Score (NAS) and fibrosis stage. Terminal endpoints included quantitative liver histology and transcriptome signatures as well as blood and liver biochemistry. PF-05231023 significantly reduced body weight, hepatomegaly, plasma transaminases and plasma/liver lipids in GAN DIO-NASH mice. Notably, PF-05231023 reduced both NAS (≥2-point improvement) and fibrosis stage (1-point improvement). Improvements in NASH and fibrosis severity were supported by reduced quantitative histological markers of steatosis, inflammation and fibrogenesis as well as improvements in disease-associated liver transcriptome signatures. Conclusion: PF-05231023 reduces NASH and fibrosis severity in a translational biopsy-confirmed mouse model of NASH, supporting development of FGF21 analogues for the treatment of NASH.

Analysis of the Efficacy and the Long-term Metabolic and Nutritional Status of Sleeve Gastrectomy with Transit Bipartition Compared to Roux-en-Y Gastric Bypass in Obese Rats

PURPOSE

Sleeve gastrectomy with transit bipartition (SG-TB) could be an attractive alternative to Roux-en-Y gastric bypass (RYGB) on weight loss and improvement of comorbidities in patients with obesity. However, there is little long-term data. Translational research on a rat model could allow long-term projection to assess efficacy and safety of SG-TB. The aim of this research was to evaluate the long-term efficacy and safety of SG-TB compared to RYGB and SHAM in rat model.

MATERIALS AND METHODS

Ninety-four male obese Wistar rats were distributed into 3 groups: SG-TB (n = 34), RYGB (n = 32), and SHAM (control group, n = 28). The percentage of total weight loss (%TWL), coprocalorimetry, glucose and insulin tolerance test, insulin, GLP-1, PYY, and GIP before and after surgery were assessed. The animals were followed over 6 months (equivalent to 16 years in humans).

RESULTS

At 6 months, %TWL was significantly greater(p = 0.025) in the SG-TB group compared to the RYGB group. There was no difference between the groups (p = 0.86) in malabsorption 15 and 120 days postoperatively. Glucose tolerance was significantly improved (p = 0.03) in the SG-TB and RYGB groups compared to the preoperative state. Insulin secretion, at 3 months, was significantly more important in the SG-TB group (p = 0.0003), compared to the RYGB and SHAM groups. GLP-1 secretion was significantly increased in the SG-TB and RYGB groups compared to the preoperative state (p = 0.001) but similar between SG-TB and RYGB animals (p = 0.72).

CONCLUSION

In a rat model, at long term compared to RYGB, SG-TB provides greater and better-maintained weight loss and an increased insulin secretion without impairing nutritional status.

Nonhuman Primate Models to Explore Mechanisms Underlying Early-Life Temperamental Anxiety

Anxiety disorders are among the most prevalent psychiatric disorders, causing significant suffering and disability. Behavioral inhibition is a temperament that is linked to an increased risk for the later development of anxiety disorders and other stress-related psychopathology, and understanding the neural systems underlying this dispositional risk could provide insight into novel treatment targets for anxiety disorders. Nonhuman primates (NHPs) have anxiety-related temperaments that are similar to those of humans with behavioral inhibition, facilitating the design of translational models related to human psychopathology. Characterization of our NHP model of behavioral inhibition, which we term anxious temperament (AT), reveals that it is trait-like. Exploration of the neural substrates of AT in NHPs has revealed a distributed neural circuit that is linked to individual differences in AT, which includes the dorsal amygdala. AT-related metabolism in the dorsal amygdala, including the central nucleus, is stable across time and can be detected even in safe contexts, suggesting that AT has trait-like neural signatures within the brain. The use of lesioning and novel chemogenetic methods allows for mechanistic perturbation of the amygdala to determine its causal contribution to AT. Studies characterizing the molecular bases for individual differences in AT in the dorsal amygdala, which take advantage of novel methods for probing cellular and molecular systems, suggest involvement of neurotrophic systems, which point to the importance of neuroplasticity in AT. These novel methods, when used in combination with translational NHP models such as AT, promise to provide insights into the brain systems underlying the early risk for anxiety disorder development.

Model based approach for estimating the dosage regimen of indomethacin a potential antiviral treatment of patients infected with SARS CoV-2

To face SARS-CoV-2 pandemic various attempts are made to identify potential effective treatments by repurposing available drugs. Among them, indomethacin, an anti-inflammatory drug, was shown to have potent in-vitro antiviral properties on human SARS-CoV-1, canine CCoV, and more recently on human SARS-CoV-2 at low micromolar range. Our objective was to show that indomethacin could be considered as a promising candidate for the treatment of SARS-CoV-2 and to provide criteria for comparing benefits of alternative dosage regimens using a model-based approach. A multi-stage model-based approach was developed to characterize % of recovery and viral load in CCoV-infected dogs, to estimate the PK of indomethacin in dog and human using published data after administration of immediate (IR) and sustained-release (SR) formulations, and to estimate the expected antiviral activity as a function of different assumptions on the effective exposure in human. Different dosage regimens were evaluated for IR formulation (25 mg and 50 mg three-times-a-day, and 25 mg four-times-a-day), and SR formulation (75 mg once and twice-a-day). The best performing dosing regimens were: 50 mg three-times-a-day for the IR formulation, and 75 mg twice-a-day for the SR formulation. The treatment with the SR formulation at the dose of 75 mg twice-a-day is expected to achieve a complete response in three days for the treatment in patients infected by the SARS-CoV-2 coronavirus. These results suggest that indomethacin could be considered as a promising candidate for the treatment of SARS-CoV-2 whose potential therapeutic effect need to be further assessed in a prospective clinical trial.

Tenovin-6 induces the SIRT-independent cell growth suppression and blocks autophagy flux in canine hemangiosarcoma cell lines

Canine hemangiosarcoma (HSA) is a commonly occurring aggressive tumor stemming from the vascular endothelial cells and is considered to be a good model for a similar disease in humans, called angiosarcoma. In this study, we reviewed drug libraries to identify new signal transduction inhibitors that can suppress the cell growth of canine HSA in vitro. We observed that tenovin-6, a sirtuin (SIRT) inhibitor, inhibited cell proliferation and induced cell death in three canine HSA cell lines (JuB4, Re12, and Ud6). These effects were induced through G1 cell cycle arrest and caspase-3 activation. Although tenovin-6 is known as an inhibitor of SIRT1 and SIRT2, knockout (KO) of genes encoding SIRT1 and/or SIRT2 had no apparent impact on cell proliferation in canine HSA. In addition, tenovin-6 showed cell growth inhibition in SIRT KO cells, as well as parental cells. These results indicated the cytotoxicity of tenovin-6 was a SIRT-independent event. Instead, we found that tenovin-6 inhibited autophagy flux in canine HSA cells, as evidenced by the suppression of lysosomal proteolysis. These results suggested that tenovin-6 induces cell growth suppression in canine HSA cells by impairing the lysosomal function. Therefore, tenovin-6 could be used in a new therapeutic strategy to treat canine HSA.

Use of precision cut lung slices as a translational model for the study of lung biology

Animal models remain invaluable for study of respiratory diseases, however, translation of data generated in genetically homogeneous animals housed in a clean and well-controlled environment does not necessarily provide insight to the human disease situation. In vitro human systems such as air liquid interface (ALI) cultures and organ-on-a-chip models have attempted to bridge the divide between animal models and human patients. However, although 3D in nature, these models struggle to recreate the architecture and complex cellularity of the airways and parenchyma, and therefore cannot mimic the complex cell-cell interactions in the lung. To address this issue, lung slices have emerged as a useful ex vivo tool for studying the respiratory responses to inflammatory stimuli, infection, and novel drug compounds. This review covers the practicality of precision cut lung slice (PCLS) generation and benefits of this ex vivo culture system in modeling human lung biology and disease pathogenesis.

Of dogs and hookworms: man's best friend and his parasites as a model for translational biomedical research

We present evidence that the dog hookworm (Ancylostoma caninum) is underutilised in the study of host-parasite interactions, particularly as a proxy for the human-hookworm relationship. The inability to passage hookworms through all life stages in vitro means that adult stage hookworms have to be harvested from the gut of their definitive hosts for ex vivo research. This makes study of the human-hookworm interface difficult for technical and ethical reasons. The historical association of humans, dogs and hookworms presents a unique triad of positive evolutionary pressure to drive the A. caninum-canine interaction to reflect that of the human-hookworm relationship. Here we discuss A. caninum as a proxy for human hookworm infection and situate this hookworm model within the current research agenda, including the various 'omics' applications and the search for next generation biologics to treat a plethora of human diseases. Historically, the dog hookworm has been well described on a physiological and biochemical level, with an increasing understanding of its role as a human zoonosis. With its similarity to human hookworm, the recent publications of hookworm genomes and other omics databases, as well as the ready availability of these parasites for ex vivo culture, the dog hookworm presents itself as a valuable tool for discovery and translational research.

Midazolam Efficacy Against Acute Hydrogen Sulfide-Induced Mortality and Neurotoxicity

Hydrogen sulfide (H₂S) is a colorless, highly neurotoxic gas. It is not only an occupational and environmental hazard but also of concern to the Department of Homeland Security for potential nefarious use. Acute high-dose H₂S exposure causes death, while survivors may develop neurological sequelae. Currently, there is no suitable antidote for treatment of acute H₂S-induced neurotoxicity. Midazolam (MDZ), an anti-convulsant drug recommended for treatment of nerve agent intoxications, could also be of value in treating acute H₂S intoxication. In this study, we tested the hypothesis that MDZ is effective in preventing/treating acute H₂S-induced neurotoxicity. This proof-of-concept study had two objectives: to determine whether MDZ prevents/reduces H₂S-induced mortality and to test whether MDZ prevents H₂S-induced neurological sequelae. MDZ (4 mg/kg) was administered IM in mice, 5 min pre-exposure to a high concentration of H₂S at 1000 ppm or 12 min post-exposure to 1000 ppm H₂S followed by 30 min of continuous exposure. A separate experiment tested whether MDZ pre-treatment prevented neurological sequelae. Endpoints monitored included assessment of clinical signs, mortality, behavioral changes, and brain histopathological changes. MDZ significantly reduced H₂S-induced lethality, seizures, knockdown, and behavioral deficits (p < 0.01). MDZ also significantly prevented H₂S-induced neurological sequelae, including weight loss, behavior deficits, neuroinflammation, and histopathologic lesions (p < 0.01). Overall, our findings show that MDZ is a promising drug for reducing H₂S-induced acute mortality, neurotoxicity, and neurological sequelae.

Lithium reverses behavioral and axonal transport-related changes associated with ANK3 bipolar disorder gene disruption

Ankyrin 3 (ANK3) has been implicated as a genetic risk factor for bipolar disorder (BD), however the resulting pathophysiological and treatment implications remain elusive. In a preclinical systems biological approach, we aimed to characterize the behavioral and proteomic effects of Ank3 haploinsufficiency and chronic mood-stabilizer treatment in mice. Psychiatric-related behavior was evaluated with the novelty-suppressed feeding (NSF) paradigm, elevated plus maze (EPM) and a passive avoidance task (PAT). Tandem mass spectrometry (MS^E) was employed for hippocampal proteome profiling. A functional enrichment approach based on protein-protein interactions (PPIs) was performed to outline which biological processes in the hippocampus were affected by Ank3 haploinsufficiency and lithium treatment. Proteomic abundance changes as detected by MS^E or highlighted by PPI network modelling were followed up by targeted selected reaction monitoring (SRM). Increased psychiatric-related behavior in Ank3+/- mice was ameliorated by lithium in all assessments (NSF, EPM, PAT). MS^E followed by modular PPI clustering and functional annotation enrichment pointed towards kinesin-related axonal transport and glutamate signaling as mediators of Ank3+/- pathophysiology and lithium treatment. SRM validated this hypothesis and further confirmed abundance changes of ANK3 interaction partners. We propose that psychiatric-related behavior in Ank3+/- mice is connected to a disturbance of the kinesin cargo system, resulting in a dysfunction of neuronal ion channel and glutamate receptor transport. Lithium reverses this molecular signature, suggesting the promotion of anterograde kinesin transport as part of its mechanism of action in ameliorating Ank3-related psychiatric-related behavior.

The TetO rat as a new translational model for type 2 diabetic retinopathy by inducible insulin receptor knockdown

AIMS/HYPOTHESIS

Although the renin-angiotensin system plays an important role in the progression of diabetic retinopathy, its influence therein has not been systematically evaluated. Here we test the suitability of a new translational model of diabetic retinopathy, the TetO rat, for addressing the role of angiotensin-II receptor 1 (AT1) blockade in experimental diabetic retinopathy.

METHODS

Diabetes was induced by tetracycline-inducible small hairpin RNA (shRNA) knockdown of the insulin receptor in rats, generating TetO rats. Systemic treatment consisted of an AT1 blocker (ARB) at the onset of diabetes, following which, 4-5 weeks later the retina was analysed in vivo and ex vivo. Retinal function was assessed by Ganzfeld electroretinography (ERG).

RESULTS

Retinal vessels in TetO rats showed differences in vessel calibre, together with gliosis. The total number and the proportion of activated mononuclear phagocytes was increased. TetO rats presented with loss of retinal ganglion cells (RGC) and ERG indicated photoreceptor malfunction. Both the inner and outer blood-retina barriers were affected. The ARB treated group showed reduced gliosis and an overall amelioration of retinal function, alongside RGC recovery, whilst no statistically significant differences in vascular and inflammatory features were detected.

CONCLUSIONS/INTERPRETATION

The TetO rat represents a promising translational model for the early neurovascular changes associated with type 2 diabetic retinopathy. ARB treatment had an effect on the neuronal component of the retina but not on the vasculature.

Knee osteoarthritis pain following medial meniscectomy in the nonhuman primate

OBJECTIVE

A number of promising compounds developed for osteoarthritic pain have failed to demonstrate clinical efficacy. To enhance preclinical translational research for osteoarthritis, a model of knee osteoarthritis pain was developed in Macaca fascicularis and the effects of two distinct pharmacological classes of drugs were tested on pain-related behavior.

DESIGN

Behavioral assessments were developed specifically for the macaque. Baseline knee pressure threshold and weight bearing were assessed prior to a unilateral medial meniscectomy (MMx). Fifteen days following MMx, macaques underwent a once daily exercise regimen for 36 days. Sixty-seven days following MMx, macaques were assigned to one of three treatment groups (n = 3/group), either non-steroidal anti-inflammatory drug (NSAID) diclofenac, NK1 receptor antagonist aprepitant or vehicle, and treated for 5 days. Animals were tested 3-4 h after p.o. dosing and testing was performed blinded. Treatment utilized a crossover design-each animal received all treatments-and a 9-day washout period was utilized between treatments.

RESULTS

Vehicle-treated macaques consistently demonstrated decreased ipsilateral pressure threshold ("hyperalgesia") and decreased weight bearing. While diclofenac increased weight bearing and pressure threshold, full attenuation of pain was not obtained. No significant improvement of either knee pressure or weight bearing was observed with aprepitant.

CONCLUSIONS

Unilateral MMx in the macaque evoked pain-related behaviors and knee joint pathology reminiscent of osteoarthritis. The behavioral endpoints were sensitive to NSAID treatment but not sensitive to NK1 receptor block, which parallel clinical findings. The current macaque osteoarthritis model could be used to test potential treatments for osteoarthritis pain.

Adaptation of the Basso-Beattie-Bresnahan locomotor rating scale for use in a clinical model of spinal cord injury in dogs

BACKGROUND

Naturally occurring acute spinal cord injury (SCI) in pet dogs provides an important clinical animal model through which to confirm and extend findings from rodent studies; however, validated quantitative outcome measures for dogs are limited.

NEW METHOD

We adapted the Basso Beattie Bresnahan (BBB) scale for use in a clinical dog model of acute thoracolumbar SCI. Based on observation of normal dogs, modifications were made to account for species differences in locomotion. Assessments of paw and tail position, and trunk stability were modified to produce a 19 point scale suitable for use in dogs, termed the canine BBB scale (cBBB). Pet dogs with naturally occurring acute SCI were assigned cBBB scores at 3, 10 and 30days after laminectomy.

RESULTS

Scores assigned via the cBBB were stable across testing sessions in normal dogs but increased significantly between days 3 and 30 in SCI-affected dogs (p=0.0003). The scale was highly responsive to changes in locomotor recovery over a 30day period, with a standardized response mean of 1.34.

COMPARISON WITH EXISTING METHODS

Concurrent validity was good, with strong correlations observed between the cBBB and two other locomotor scales, the OSCIS (r=0.94; p<0.001) and the MFS (r=0.85; p<0.0001). cBBB scores inversely correlated with other assessments of recovery including mechanical sensory threshold (r=-0.68; p<0.0001) and coefficient of variation of stride length (r=-0.49; p<0.0001).

CONCLUSIONS

These results support the use of the cBBB to assess locomotor recovery in canine clinical translational models of SCI.

Striatal magnetic resonance spectroscopy abnormalities in young adult SAPAP3 knockout mice

BACKGROUND

Obsessive compulsive disorder (OCD) is a debilitating condition with lifetime prevalence of 1-3%. OCD typically arises in youth but delays in diagnosis impede optimal treatment and developmental studies of the disorder. Research using genetically modified rodents may provide models of etiology that enable earlier detection and intervention. The SAPAP3 knockout (KO) transgenic mouse was developed as an animal model of OCD and related disorders (OCRD). KO mice exhibit compulsive self-grooming behavior analogous to behaviors found in people with OCRD. Striatal hyperactivity has been reported in these mice and in humans with OCD.

METHODS

Striatal and medial frontal cortex 9.4 Tesla proton spectra were acquired from young adult SAPAP3 KO and wild-type control mice to determine whether KO mice have metabolic and neurochemical abnormalities.

RESULTS

Young adult KO mice had lower striatal lactate (P=0.006) and glutathione (P=0.039) levels. Among all mice, striatal lactate and glutathione levels were associated (R=0.73, P=0.007). We found no group differences in medial frontal cortex metabolites. At the age range studied, only 1 of 8 KO mice had skin lesions indicative of severe compulsive grooming.

CONCLUSION

Young adult SAPAP3 KO mice have striatal but not medial frontal cortex MRS abnormalities that may reflect striatal hypermetabolism accompanied by oxidative stress. These abnormalities typically preceded the onset of severe compulsive grooming. Our findings are consistent with striatal hypermetabolism in OCD. Together, these results suggest that striatal MRS measures of lactate or glutathione might be useful biomarkers for early detection of risk for developing compulsive behavior disorders.

Workshop report: The medaka model for comparative assessment of human disease mechanisms

Results of recent studies showing the utility of medaka as a model of various human disease states were presented at the 7th Aquatic Models of Human Disease Conference (December 13-18, 2014, Austin, TX). This conference brought together many of the most highly regarded national and international scientists that employ the medaka model in their investigations. To take advantage of this opportunity, a cohort of established medaka researchers were asked to stay an extra day and represent the medaka scientific community in a workshop entitled "The Medaka Model for Comparative Assessment of Human Disease Mechanisms." The central purpose of this medaka workshop was to assess current use and project the future resource needs of the American medaka research community. The workshop sought to spur discussions of issues that would promote more informative comparative disease model studies. Finally, workshop attendees met together to propose, discuss, and agree on recommendations regarding the most effective research resources needed to enable US scientists to perform experiments leading to impacting experimental results that directly translate to human disease. Consistent with this central purpose, the workshop was divided into two sessions of invited speakers having expertise and experience in the session topics. The workshop hosted 20 scientific participants (Appendices 1 and 2), and of these, nine scientists presented formal talks. Here, we present a summary report stemming from workshop presentations and subsequent round table discussions and forward recommendations from this group that we believe represent views of the overall medaka research community.

Development of translational preclinical models in substance abuse: Effects of cocaine administration on cocaine choice in humans and non-human primates

Human drug use involves repeated choices to take drugs or to engage in alternative behaviors. The purpose of this study was to examine how response cost for cocaine and the value of an alternative reinforcer (opportunity to play a game of chance) and how 'free' doses (with minimal response cost) affected cocaine choice. Two laboratory studies of cocaine self-administration were conducted in a group of humans who were habitual cocaine smokers and in a group of rhesus monkeys that intravenously self-administered cocaine. Nine human cocaine smokers who were not seeking treatment for their cocaine were repeatedly presented with the choice to smoke 25mg cocaine base or play a game of chance for a monetary bonus paid at study completion. The response cost for choosing cocaine varied (up to 4000 responses/dose) and the number of game plays varied (up to 8). In this sample of humans, increasing either the response cost for cocaine or increasing the value of the alternative reinforcer did not significantly affect cocaine choice, while increasing both simultaneously slightly decreased cocaine choice and increased choice of the alternative. In monkeys, the dose-response function for cocaine self-administration (10 choices of 0.0125-0.1mg/kg/infusion vs. candy coated chocolate) was steep and we failed to achieve a 50/50 cocaine/candy choice even after substantially manipulating cost and number of candies available. Providing a large 'free' self-administered cocaine dose to humans did not significantly affect cocaine choice, whereas in monkeys, a large free dose of cocaine decreased cocaine choice when higher doses of cocaine were available for self-administration. The present results demonstrate that in the laboratory, it is difficult to modify on-going cocaine self-administration behavior in both humans and non-human primates.

Articular osteochondrosis: a comparison of naturally-occurring human and animal disease

BACKGROUND

Osteochondrosis (OC) is a common developmental orthopedic disease affecting both humans and animals. Despite increasing recognition of this disease among children and adolescents, its pathogenesis is incompletely understood because clinical signs are often not apparent until lesions have progressed to end-stage, and examination of cadaveric early lesions is not feasible. In contrast, both naturally-occurring and surgically-induced animal models of disease have been extensively studied, most notably in horses and swine, species in which OC is recognized to have profound health and economic implications. The potential for a translational model of human OC has not been recognized in the existing human literature.

OBJECTIVE

The purpose of this review is to highlight the similarities in signalment, predilection sites and clinical presentation of naturally-occurring OC in humans and animals and to propose a common pathogenesis for this condition across species.

STUDY DESIGN

Review.

METHODS

The published human and veterinary literature for the various manifestations of OC was reviewed. Peer-reviewed original scientific articles and species-specific review articles accessible in PubMed (US National Library of Medicine) were eligible for inclusion.

RESULTS

A broad range of similarities exists between OC affecting humans and animals, including predilection sites, clinical presentation, radiographic/MRI changes, and histological appearance of the end-stage lesion, suggesting a shared pathogenesis across species.

CONCLUSION

This proposed shared pathogenesis for OC between species implies that naturally-occurring and surgically-induced models of OC in animals may be useful in determining risk factors and for testing new diagnostic and therapeutic interventions that can be used in humans.