Traces of Canine Inflammatory Bowel Disease Reflected by Intestinal Organoids

Inflammatory bowel disease (IBD) is a chronic inflammatory condition that affects humans and several domestic animal species, including cats and dogs. In this study, we have analyzed duodenal organoids derived from canine IBD patients using quantitative proteomics. Our objective was to investigate whether these organoids show phenotypic traits of the disease compared with control organoids obtained from healthy donors. To this aim, IBD and control organoids were subjected to quantitative proteomics analysis via liquid chromatography–mass spectrometry. The obtained data revealed notable differences between the two groups. The IBD organoids exhibited several alterations at the levels of multiple proteins that are consistent with some known IBD alterations. The observed phenotype in the IBD organoids to some degree mirrors the corresponding intestinal condition, rendering them a compelling approach for investigating the disease and advancing drug exploration. Additionally, our study revealed similarities to some human IBD biomarkers, further emphasizing the translational and comparative value of dogs for future investigations related to the causes and treatment of IBD. Relevant proteins such as CALU, FLNA, MSN and HMGA2, which are related to intestinal diseases, were all upregulated in the IBD duodenal organoids. At the same time, other proteins such as intestinal keratins and the mucosal immunity PIGR were depleted in these IBD organoids. Based on these findings, we propose that these organoids could serve as a valuable tool for evaluating the efficacy of therapeutic interventions against canine IBD

Proposal for rational antibacterials use in the diagnosis and treatment of dogs with chronic diarrhoea

Chronic diarrhoea is a frequent complaint in canine practice and the diagnostic path is often characterised by numerous diagnostic tests and stepwise empirical treatments, often applied before gastrointestinal (GI) endoscopy/mucosal biopsies. These include dietary interventions (novel protein, hydrolysed protein diet), parasiticides and still, in many cases, antibacterials. Indiscriminate use of antibacterial drugs risks detrimental consequences for both the individual patient (antimicrobial resistance, long-term disruption of intestinal bacterial populations, potential worsening of GI signs) and general public. For that reason, in this Perspective essay we advocate use of antibacterials only after histopathologic evaluation of GI biopsies or, for those cases in which endoscopy is not possible, after other therapeutic trials, such as diet/pre-probiotics or anti-inflammatory drugs have proven unsuccessful. They should be reserved, after appropriate dietary trials, for those canine chronic diarrhoeic patients with signs of true primary infection (i.e. signs of systemic inflammatory response syndrome or evidence of adherent-invasive bacteria) that justify antibacterial use

Formerly bile-farmed bears as a model of accelerated ageing

Bear bile-farming is common in East and Southeast Asia and this farming practice often results in irreversible health outcomes for the animals. We studied long-term effects of chronic bacterial and sterile hepatobiliary inflammation in 42 Asiatic black bears (Ursus thibetanus) rescued from Vietnamese bile farms. The bears were examined under anesthesia at least twice as part of essential medical interventions. All bears were diagnosed with chronic low-grade sterile or bacterial hepatobiliary inflammation along with pathologies from other systems. Our main finding was that the chronic low-grade inflammatory environment associated with bile extraction in conjunction with the suboptimal living conditions on the farms promoted and accelerated the development of age-related pathologies such as chronic kidney disease, obese sarcopenia, cardiovascular remodeling, and degenerative joint disease. Through a biomimetic approach, we identified similarities with inflammation related to premature aging in humans and found significant deviations from the healthy ursid phenotype. The pathological parallels with inflammageing and immuno-senescence induced conditions in humans suggest that bile-farmed bears may serve as animal models to investigate pathophysiology and deleterious effects of lifestyle-related diseases

Horizontal and vertical distribution of CD3+ lymphocytes in the intestine of healthy adult and neonatal dogs

T-lymphocytes are considered to play an essential role in the pathogenesis of inflammatory bowel disease. The goal of this study was an objective determination of the distribution of gastrointestinal CD3+ lymphocytes in a standardized dog population as a gold standard for further investigations. Full thickness biopsies were obtained from seven different localizations from stomach to colon from six adults and four neonatal healthy Beagle dogs. The tissue was stained with an anti-CD3 antibody. The positive cells were counted in an area of 200,000 μm2 at four different sites per localization. In adult dogs, the horizontal distribution showed a maximum of CD3+ lymphocytes in the duodenum and jejunum. In the stomach, almost no positive cells were observed. The vertical distribution revealed an accumulation in the villi. The neonatal dogs showed a similar distribution pattern, but on average ten times less CD3+ lymphocytes in the analogous localizations and smaller differences between localizations

Establishment and characterization of a primary canine duodenal epithelial cell culture

Many mechanisms involved in the pathogenesis of chronic enteropathies or host-pathogen interactions in canine intestine have not been elucidated so far. Next to the clinical and in vivo research tools, an in vitro model of canine intestinal cell culture would be very helpful for studies at the cellular level. Therefore, the purpose of this study was to establish and characterize a primary canine duodenal epithelial cell culture. Neonatal duodenum was disrupted with trypsin-ethylenediaminetetraacetic acid (EDTA) and the mucosa scraped off and digested with collagenase and dispase. After centrifugation on a 2% sorbitol gradient, the cells were incubated at 37 degrees C in OptiMEM supplemented with Primocin, epidermal growth factor, insulin, hydrocortisone, and 10% fetal calf serum (FCS). After 24 h, the FCS concentration was reduced to 2.5%, and the temperature decreased to 33 degrees C. With this method, the cultures were growing to confluent monolayers within 5-6 d and remained viable for an average of 2 wk. Their epithelial nature was confirmed by electron microscopy and immunofluorescence staining using antibodies directed against specific cytokeratins, desmosomes, and tight junctions. The intestinal cells proliferated, as evidenced by immunolabeling with a Ki-67 antibody, and cryptal cell subpopulations could be identified. Furthermore, alkaline phosphatase and sucrase activity were detected

Small intestinal intussusception in five dogs with acute renal failure and suspected leptospirosis (L. australis)

OBJECTIVES This case series describes 5 dogs with small intestinal intussusception and acute kidney injury due to infection with Leptospira interrogans serovar Australis. CASE SERIES SUMMARY Small intestinal intussusception was observed in 4 dogs diagnosed with acute kidney injury due to leptospirosis presented between 1997 and 2005. Intussusception was diagnosed at initial presentation or later during hospitalization. An additional dog fulfilling our inclusion criteria was presented to a small animal specialty clinic nearby and was included. Upon admission, all dogs were severely azotemic and thrombocytopenic. All 5 dogs showed the strongest microscopic agglutination test serology reaction to L. interrogans serovar Australis. Two dogs survived with no apparent residual renal damage, 1 survived with subsequent mild chronic kidney disease, and 2 dogs were euthanized at the owners' request due to a guarded prognosis. NEW OR UNIQUE INFORMATION PROVIDED Intussusception can occur or may be seen in dogs with leptospirosis due to L. interrogans serovar Australis and patients should be monitored closely for this potential complication. As all 5 dogs described in this case series showed the highest titer for L. interrogans serovar Australis, these precautions may be especially applied in geographic areas where this particular serovar is seen

Comparison of the systemic phospholipid profile in dogs diagnosed with idiopathic inflammatory bowel disease or food-responsive diarrhea before and after treatment

BACKGROUND: Inflammatory bowel disease (IBD) and food-responsive diarrhea (FRD) are common chronic enteropathies in dogs, of which the exact pathogenesis has not been fully understood. In people dyslipidemia has been reported in patients with IBD, and potential therapeutic benefits of polyunsaturated fatty acids (PUFA) in the treatment of IBD have been investigated. Studies on the phospholipid profile in dogs with IBD and FRD are still lacking. AIM: To investigate the systemic phospholipid profile of dogs with IBD or FRD and to evaluate possible differences in phospholipids before and after treatment. METHODS: The phospholipids in whole blood and EDTA plasma of 32 dogs diagnosed with either IBD (n = 16) or FRD (n = 16) were analyzed by hydrophilic interaction liquid chromatography (HILIC) prior to and after initiation of treatment, which included an elimination diet enriched with PUFAs. RESULTS: A clear separation of the phospholipids between whole blood and plasma was demonstrated on principal component analysis plots. In addition to the type of specimen, treatment and disease severity were the most significant factors determining the variance of the phospholipid profile. An increase in lysolipids was observed after treatment. The phosphatidylcholine (PC) species changed from PC 38:4 before treatment to mainly lysophosphatidylcholine 18:0 after treatment. Furthermore, several differences in the abundance of individual phospholipids were identified between dogs with IBD and dogs with FRD and between treatment statuses using random forest analysis. CONCLUSION: Significant variances were identified in the phospholipid profiles of dogs with IBD and FRD. These were particularly determined by type of specimen used, disease severity and treatment status. After treatment, a shift of phospholipid species towards lysophosphatidylcholine 18:0 was observed. Future studies should further investigate the role of lipids in the pathophysiology of IBD and FRD as well as their potential therapeutic benefits

Comparison of the systemic phospholipid profile in dogs diagnosed with idiopathic inflammatory bowel disease or food-responsive diarrhea before and after treatment

BACKGROUND: Inflammatory bowel disease (IBD) and food-responsive diarrhea (FRD) are common chronic enteropathies in dogs, of which the exact pathogenesis has not been fully understood. In people dyslipidemia has been reported in patients with IBD, and potential therapeutic benefits of polyunsaturated fatty acids (PUFA) in the treatment of IBD have been investigated. Studies on the phospholipid profile in dogs with IBD and FRD are still lacking. AIM: To investigate the systemic phospholipid profile of dogs with IBD or FRD and to evaluate possible differences in phospholipids before and after treatment. METHODS: The phospholipids in whole blood and EDTA plasma of 32 dogs diagnosed with either IBD (n = 16) or FRD (n = 16) were analyzed by hydrophilic interaction liquid chromatography (HILIC) prior to and after initiation of treatment, which included an elimination diet enriched with PUFAs. RESULTS: A clear separation of the phospholipids between whole blood and plasma was demonstrated on principal component analysis plots. In addition to the type of specimen, treatment and disease severity were the most significant factors determining the variance of the phospholipid profile. An increase in lysolipids was observed after treatment. The phosphatidylcholine (PC) species changed from PC 38:4 before treatment to mainly lysophosphatidylcholine 18:0 after treatment. Furthermore, several differences in the abundance of individual phospholipids were identified between dogs with IBD and dogs with FRD and between treatment statuses using random forest analysis. CONCLUSION: Significant variances were identified in the phospholipid profiles of dogs with IBD and FRD. These were particularly determined by type of specimen used, disease severity and treatment status. After treatment, a shift of phospholipid species towards lysophosphatidylcholine 18:0 was observed. Future studies should further investigate the role of lipids in the pathophysiology of IBD and FRD as well as their potential therapeutic benefits

Prevalence and characterization of hypoadrenocorticism in dogs with signs of chronic gastrointestinal disease – a multicenter study

Background Dogs with hypoadrenocorticism (HA) frequently show signs of gastrointestinal disease (SGD). The prevalence of dogs presented for chronic SGD with HA is unknown. Objectives The aims of this study were to determine the prevalence of HA in dogs with chronic SGD and to identify clinical and laboratory variables for HA in this population. Animals One hundred fifty‐one dogs with chronic SGD. Methods In this multicentered prevalence study a standardized workup was performed in prospectively enrolled dogs with SGD > 3 weeks duration. Basal serum cortisol concentration was measured in every dog with ACTH stimulation test (ACTHST) if basal serum cortisol concentration was <3 μg/dL. Results Basal serum cortisol concentration was <3 μg/dL in 80/151 (53%) dogs, <2 μg/dL in 42/151 (28%) dogs, and < 1 μg/dL in 9/151 (6%) dogs. In 6/151 dogs HA was diagnosed based on ACTHST (stimulated serum cortisol concentration < 2 μg/dL), a prevalence of 4%. There was no difference in history, physical examination, and laboratory variables between dogs with HA and those with other causes of chronic SGD. In 4/6 dogs with HA, there was melena or hematochezia indicating gastrointestinal blood loss. Hyperkalemia, hyponatremia, or both was not observed in any dog. Conclusion and Clinical Importance The prevalence of HA among dogs with chronic SGD is higher than in the general population. Based on these results, testing adrenal function should be performed as a standard screening test in dogs with chronic SGD to differentiate between HA and chronic enteropathies

Serum alpha1-proteinase inhibitor concentrations in healthy dogs - method validation and determination of reference interval and intra-individual variation

Background A chronic loss of canine 1-proteinase inhibitor (c1-PI) into the gastrointestinal (GI) tract could change the systemic proteinase-proteinase inhibitor balance. Serum c1-PI concentrations have not been studied in dogs with well-defined GI diseases. Objectives To further evaluate serum c1-PI concentrations in dogs with GI diseases, the objectives of this study were to (1) analytically validate a previously developed fecal c1-PI immunoassay to determine serum concentrations, (2) determine a population-based reference interval (RI) and assess the clinical utility, (3) determine stability of serum c1-PI, (4) determine the intra-individual variation in healthy dogs, and (5) determine the clinically relevant magnitude of change of serum c1-PI. Methods Prestudy validation of the 125I-c1-PI immunoassay included linearity, spiking recovery, and intra- and inter-assay precision. A RI was calculated with samples of healthy dogs. Stability at -20 degrees C was tested on 36 samples. Intra-individual variation was assessed using samples collected from 11 healthy dogs over a 12-week period. Results The c1-PI radioimmunoassay (RIA) was linear, accurate, precise, and reproducible. Serum c1-PI decreased by 11% after oneyear at -20 degrees C. Analytical, intra-individual, inter-individual, and total variation were 6.4, 9.9, 9.0, and 25.3%, respectively. The RI for serum c1-PI was 732-1802mg/L (n=87); there were no differences between sex and age groups. The index of individuality was 1.31. As analytical variation was > 1/2 inter-individual variation, the minimum critical difference was not determined. Conclusions The results of this study provide the basis for further evaluating serum c1-PI in dogs with GI disease. Using a population-based RI for serum c1-PI appears to be appropriate