Project description:Lipids play a critical role in the skin as components of the epidermal barrier and as sig-naling molecules. Atopic dermatitis in dogs is associated with changes in the lipid composition of the skin, but whether these precede the onset of dermatitis or occur secondary to the dermatitis is unclear. We applied rapid lipid profiling mass spectrometry methods to skin and blood samples of dogs and determined changes following systemic treatment. Thirty control dogs and 30 atopic dogs with mild to moderate dermatitis were enrolled. Marked differences in lipid profiles were observed between control, nonlesional and lesional skin of dogs. Additionally, there were significant altera-tions in the lipid composition of the blood samples indicating systemic changes in lipid metabolism. Treatment with oclacitinib or lokivetmab resulted in a significant decrease of the disease clinical severity associated with changes in skin and blood lipids. A set of lipid features of the skin were selected as biomarkers that classified samples as control or atopic dermatitis with 95% accuracy, whereas blood lipids discriminated between control and atopic dogs with 82% accuracy. These data suggest that atopic dermatitis is a systemic disease and support the use of rapid lipid profiling to identify novel biomarkers.
Project description:Canine atopic dermatitis (AD) is clinically similar to human AD, implicating it as a useful model of human eosinophilic allergic disease. To identify cutaneous gene transcription changes in relatively early inflammation of canine AD, microarrays were used to monitor transcription in normal skin (n=13) and in acute lesional AD (ALAD) and nearby visibly nonlesional AD (NLAD) skin (n=13) from dogs. Scanning the putative abnormally-transcribed genes, several potentially relevant genes, some abnormally transcribed in both NLAD and ALAD (e.g. IL6, NFAM1, MSRA, and SYK), were observed. Comparison for abnormally-transcribed genes common to two related human diseases, human AD and asthmatic chronic rhinosinusitis with nasal polyps (aCRSwNP), further identified genes or gene sets likely relevant to eosinophilic allergic inflammation. These included 1) genes associated with alternatively-activated monocyte-derived cells, including members of the monocyte chemotactic protein (MCP) gene cluster, 2) members of the IL1 family gene cluster, 3) eosinophil-associated seven transmembrane receptor EMR1 and EMR3 genes, 4) interferon-inducible genes, and 5) keratin genes associated with hair and nail formation. Overall, numerous abnormally-transcribed genes were observed only in canine AD; however, many others are common to related human eosinophilic allergic diseases and represent therapeutic targets testable in dogs with AD. Total RNA from skin biopsy specimens from 13 Healthy (i.e. Normal) dogs were compared to total RNA from acute lesional skin biopsy specimens (i.e. ALAD) and nearby visibly nonlesional skin biopsy specimens (i.e. NLAD) from 13 dogs with atopic dermatitis.
Project description:Aging alters gastrointestinal morphology, microbiota, and functionality, and is associated with increased incidence of intestinal disease. The mechanisms that contribute to these changes are poorly described. Gene expression in dogs has been evaluated for a few select genes under pathogenic or varying dietary conditions, but global gene expression profiles of aged versus young adult dogs have not been compared previously. Thus, we used canine microarrays to compare gene expression profiles of colonic epithelial tissue from geriatric and young adult dogs fed 2 different diets. Colon tissue samples were collected from 6 geriatric (12 yr-old) and 6 young adult (1 yr-old) female beagles after being fed one of two diets (animal protein-based versus plant-protein based) for 12 months. RNA samples were hybridized to Affymetrix GeneChip Canine Genome Arrays. Statistical analyses indicated that age had the greatest impact on gene expression, with 212 genes differentially expressed in geriatric dogs. Although not as robust as age, diet affected mRNA abundance of 66 genes. The effect of age was most notable, with increased expression in genes related to inflammation, stress response, cellular metabolism and cell proliferation and decreased expression in genes associated with apoptosis and defense mechanism in senior dogs. The effect of diet on gene expression was not consistent, but appeared to have a greater response in senior dogs. Six geriatric (11.1 yr old) and 6 weanling (8 wk old) female beagles were used. Three dogs of each age were assigned to one of two dietary treatments and fed for 12 months. Diets tested in this experiment were previously shown to manipulate energy metabolism. One diet was an animal-protein based diet (APB) and was composed primarily of highly digestible ingredients and animal-derived protein and fat sources (brewer’s rice, poultry by-product meal, poultry fat) and was formulated to contain 28% protein, 23% fat, and 5% dietary fiber. The other diet was a plant-protein based diet (PPB) and was composed primarily of moderately digestible plant-derived ingredients (corn, soybean meal, wheat middlings, and meat and bone meal) and was formulated to contain 26% protein, 11% fat, and 15% dietary fiber. Although the two diets were very different in terms of ingredient and chemical composition, both were formulated to meet or exceed all nutrient requirements for canine growth according to the Association of American Feed Control Officials. Young dogs were fed ad libitum to allow for adequate growth, while geriatric dogs were fed to maintain baseline BW throughout the experiment. To produce the desired metabolic effects, the PPB diet was formulated to contain a lower caloric density (APB = 5.38 kcal/g; PPB = 4.75 kcal/g) and have a lower nutrient digestibility than the APB diet. Thus, dogs fed the PPB diet needed to consume a greater (P<0.05) quantity of food (237 g/d; 1123 kcal/d) than dogs fed the APB diet (166 g/d; 893 kcal/d) to grow (young) or maintain BW (geriatrics). Even though metabolic indices were altered, mean BW among dietary treatments was not different at any time over the course of the study for young or geriatric dogs. After 12 months on experiment, animals were fasted for 12 hr and then given a lethal dose (130 mg/kg BW) of sodium pentobarbital (Euthasol, Virbac Corp., Fort Worth, TX) intravenously into the left forearm. Death was confirmed by lack of respiration and a corneal reflex, and absence of a heartbeat detected with a stethoscope placed under the left elbow. Colon samples were collected immediately after death was confirmed, flash frozen using liquid nitrogen, and stored at -80oC. Frozen samples were placed in RNAlater-ICE until epithelial layer could be scraped off and used for microarray analysis.
Project description:Gut microbiota has profound effects on obesity and associated metabolic disorders. Targeting and shaping the gut microbiota via dietary intervention using probiotics, prebiotics and synbiotics can be effective in obesity management. Despite the well-known association between gut microbiota and obesity, the microbial alternations by synbiotics intervention, especially at the functional level, are still not characterized. In this study, we investigated the effects of synbiotics on high fat diet (HFD)-induced metabolic disorders, and systematically profiled the microbial profile at both the phylogenetic and functional levels. Synbiotics significantly reversed the HFD-induced change of microbial populations at the levels of richness, taxa and OTUs. Potentially important species Faecalibaculum rodentium and Alistipes putredinis that might mediate the beneficial effects of synbiotics were identified. At the functional level, short chain fatty acid and bile acid profiles revealed that interventions significantly restored cecal levels of acetate, propionate, and butyrate, and synbiotics reduced the elevated total bile acid level. Metaproteomics revealed the effect of synbiotics might be mediated through pathways involved in carbohydrate, amino acid, and energy metabolisms, replication and repair, etc. These results suggested that dietary intervention using our novel synbiotics alleviated HFD-induced weight gain and restored microbial ecosystem homeostasis phylogenetically and functionally.
Project description:Pet dogs may provide a useful large-animal model of spontaneously occuring non-Hodgkin lymphoma, but complete molecular characterization is lacking. We used gene expression microarrays to molecularly characterize canine lymphoma, and found similarities between canine B-cell lymphoma and human diffuse large B-cell lymphoma. We isolated RNA from pre-treatment biopsies from dogs with B-cell lymphoma and performed gene expression profiling.
Project description:Lipids play a critical role in the skin as components of the epidermal barrier and as sig-naling molecules. Atopic dermatitis in dogs is associated with changes in the lipid composition of the skin, but whether these precede the onset of dermatitis or occur secondary to the dermatitis is unclear. We applied rapid lipid profiling mass spectrometry methods to skin and blood samples of dogs and determined changes following systemic treatment. Thirty control dogs and 30 atopic dogs with mild to moderate dermatitis were enrolled. Marked differences in lipid profiles were observed between control, nonlesional and lesional skin of dogs. Additionally, there were significant altera-tions in the lipid composition of the blood samples indicating systemic changes in lipid metabolism. Treatment with oclacitinib or lokivetmab resulted in a significant decrease of the disease clinical severity associated with changes in skin and blood lipids. A set of lipid features of the skin were selected as biomarkers that classified samples as control or atopic dermatitis with 95% accuracy, whereas blood lipids discriminated between control and atopic dogs with 82% accuracy. These data suggest that atopic dermatitis is a systemic disease and support the use of rapid lipid profiling to identify novel biomarkers.
Project description:Gut microbiota participates in diverse metabolic and homeostatic functions related to health and well-being. Individual variation in its composition depends on many factors including dietary factors. We profiled enzymatic activity of fecal microbiota in 63 healthy adult individuals using metaproteomics, and identified Bacteroides and Prevotella –derived microbial CAZy (carbohydrate-active) enzymes involved in glycan foraging. One particular profile with many Bacteroides-derived CAZy was identified in one-third of subjects (n=20), and it associated with high abundancy of Bacteroides in most subjects. In other subjects (n=8) with dietary parameters similar to former, microbiota showed intense expression of Prevotella-derived CAZy including exo−beta−(1,4)−xylanase, xylan-1,4−beta−xylosidase, alpha−L−arabinofuranosidase and several other CAZy belonging to glycosyl hydrolase families involved in digestion of complex plant-derived polysaccharides. This associated invariably with robust representation of Prevotella in gut microbiota, while subjects with intermediate representation of Prevotella showed no CAZy profile. Identification of Bacteroides- and Prevotella-derived CAZy in microbiota proteome and their association with robust differences in microbiota composition, the latter with exceptionally high Prevotella abundancy in the gut, are in evidence of individual variation in metabolic adaptation of gut microbiota with an impact on colonizing competence.