Scoping review of the use of mesenchymal stem and stromal cell products in cats, Part 1: current logistics and safety.

Despite a pressing need for new therapies to address unmet veterinary medical need, no approved stem cell products are available for use in cats in the US. To evaluate the current state of mesenchymal stem or stromal cell (MSC) research in cats, a scoping review of published literature was performed, which identified 108 publications related to feline MSCs. Twenty-six of the articles described administration of MSC products to a total of 215 cats. Twelve of the studies included a control group. These experimental and clinical trials used 7 cell sources, 9 administration routes, 12 delivery vehicles, and a 300-fold range in dosages for initial studies in healthy cats and cats with 12 naturally occurring and induced diseases. The majority of studies administered 2 doses of allogeneic, adipose-derived MSC IV and monitored a median of 6.5 treated cats for a median of 90 days. The majority (150/215 [69.8%]) of cats had no reported adverse events associated with treatment. Although an increase in feline MSC publications in the past 10 years indicates progress, the wide variety and small number of studies using MSCs and MSC products in cats demonstrates that current evaluations are mostly still in the discovery phase, and several issues remain related to larger scale trials using MSC products in cats. The current available publications provide information to direct further clinical study development and informed owner consent for study enrollment.

Scoping review of the use of mesenchymal stem and stromal cell products in cats, Part 2: current scope and efficacy.

A scoping review of published literature found 108 articles related to mesenchymal stem or stromal cell (MSC) use in cats. Twenty-four of the publications summarized the treatment of 192 cats with MSC products for 12 naturally occurring and induced diseases. These trials used a variety of cell sources, administration routes, delivery vehicles, and dosages. The majority of studies did not have a control group. The disease with the largest number of cats administered MSCs thus far is chronic kidney disease (n = 59 cats). The majority of cats had no adverse events associated with treatment, which supports continued interest in the potential use of MSC products to address unmet medical needs. Treatment outcomes of the 192 cats have ranged from no response to long-term cure, depending on the disease being treated and the particular study. Some of these early studies show promise and provide significant information to direct both the design and focus of larger clinical trials investigating the safety and efficacy of MSC treatment for veterinary and human applications.

Synovial extramedullary hematopoiesis in a dog.

OBJECTIVE: Synovial extramedullary hematopoiesis is a rarely reported condition in humans and, to date, has never been reported in canines. This case report describes the clinical presentation, diagnostic work-up, treatment, and outcome of a canine case confirmed to have hematopoietic tissue within multiple joints. ANIMAL: A client-owned canine. CLINICAL PRESENTATION, PROGRESSION, AND PROCEDURES: The clinical presentation was most consistent with immune-mediated polyarthritis, and arthrocentesis was performed in multiple joints for cytological evaluation and culture. Cytology revealed evidence of extramedullary hematopoiesis, and shortly thereafter the dog was diagnosed with immune-mediated hemolytic anemia and thrombocytopenia. TREATMENT AND OUTCOME: Pregabalin, prednisolone, clopidogrel, and cyclosporine were started, and after several recheck appointments and dose adjustments, the dog's clinical signs resolved for all conditions. CLINICAL RELEVANCE: Unusual sites of extramedullary hematopoietic tissue may result in a clinical presentation for which more traditional etiologies and differentials are not applicable.

Comparing adipose-derived mesenchymal stem cells with prednisolone for the treatment of feline inflammatory bowel disease.

OBJECTIVES: The objective of this study was to compare the efficacy of feline mesenchymal stem cells (fMSC) with prednisolone as a treatment for inflammatory bowel disease (IBD) in cats. METHODS: Cats with chronic enteropathy that failed a 2-week diet trial and were not found to have significant concurrent disease were eligible for the study. If endoscopic biopsies confirmed a histopathologic diagnosis of IBD, the cat was randomly assigned to either the fMSC or prednisolone groups. Owners were blinded to the grouping. Stem cell treatment consisted of two intravenous injections of 2 × 106 cells/kg of freshly cultured allogeneic stem cells separated by 2 weeks. Prednisolone treatment was 1-2 mg/kg PO q24h, tapered according to clinical response. Owners were asked to make no changes (eg, diet and other medications) for the first 2 months, at which time they either continued to the 6-month recheck with no changes, or 'failed' treatment and owners were unblinded and changes made as necessary. RESULTS: Six prednisolone and six fMSC treatment cats completed the study. All six prednisolone group cats were spayed females with a mean age of 8.3 years (range 2-14), a mean body weight of 3.6 kg (range 2.5-4.8) and a mean pretreatment Feline Chronic Enteropathy Activity Index (FCEAI) score of 3.6 (range 2-6). The six stem cell cats included three spayed females and three castrated males, and had a mean age of 8.0 years (range 4.5-13), a mean body weight of 4.9 kg (range 4.0-5.9) and a mean pretreatment FCEAI score of 3.7 (range 2-5). One cat in each group failed at the 2-month recheck. At the 6-month recheck, the mean FCEAI score for the prednisolone group was 3.7 (range 0.5-9) and 0.75 (range 0-1.5) for the fMSC group. CONCLUSIONS AND RELEVANCE: These results suggest that this specific fMSC protocol appears to be as effective in the treatment of feline IBD as a standard course of prednisolone therapy.

Impact of specimen type on findings for bacterial composition within the intestinal tract of dogs and cats with and without chronic enteropathy.

OBJECTIVE: To compare bacterial diversity and community composition among fecal, rectal swab, and colonic mucosal biopsy specimens from dogs and cats with and without chronic enteropathy (CE). ANIMALS: 9 healthy dogs, 8 dogs with CE, 8 healthy cats, and 9 cats with CE. PROCEDURES: In a cross-sectional study design, fecal, rectal swab, and colonic mucosal biopsy specimens were obtained by colonoscopy from healthy dogs and dogs and cats with CE. Fecal and rectal swab specimens were collected from healthy cats. Genomic DNA was extracted, the 16S rRNA V4 gene region was amplified, and sequencing was performed by use of primers 515F to 806R on a paired-end platform. RESULTS: For healthy dogs and dogs and cats with CE, bacterial diversity based on the Chao1 estimate of total species richness was higher for colonic mucosal biopsy specimens than for fecal specimens. Analysis of similarities by use of the Bray-Curtis dissimilarity index revealed that the bacterial communities captured in rectal swab specimens were similar to those captured in fecal specimens for healthy dogs and dogs with CE and similar to those captured in colonic mucosal biopsy specimens for both dog groups and cats with CE. CONCLUSIONS AND CLINICAL RELEVANCE: Rectal swab and colonic biopsy specimens were successfully used to characterize the bacteriome of the intestinal tract in dogs and cats by 16S rRNA gene sequencing. Although the specimen types evaluated in this study were not interchangeable in results, rectal swab specimens were practical to collect from dogs and cats to study bacterial composition within the intestinal tract and may provide an alternative to colonic mucosal biopsy and fecal specimens.

Evidence-Based Medicine: Ultrasound-Guided Percutaneous Cholecystocentesis in the Cat.

Cholangitis is a common cause of hepatobiliary disease in the cat. Feline cholangitis is characterized as neutrophilic (acute or chronic), lymphocytic, or caused by liver flukes. The neutrophilic form is caused by bacterial infection of the biliary system, and identification of the specific bacterial agent guides treatment. Bile is the sample of choice for cytology and bacterial culture in these cases, and percutaneous ultrasound-guided cholecystocentesis is used to obtain that sample. This review covers the literature that provides evidence for safety and usefulness of percutaneous ultrasound-guided cholecystocentesis as part of the diagnostic work-up of cats suspected of having hepatobiliary disease.

Long-term impact of tylosin on fecal microbiota and fecal bile acids of healthy dogs.

BACKGROUND: Tylosin is commonly prescribed to dogs with diarrhea. Orally administered antibiotics may alter the intestinal microbiota, which is responsible for crucial key bile acid (BA) biotransformation reactions. OBJECTIVES: To prospectively evaluate the impact of tylosin administration on fecal microbiota and unconjugated bile acids (UBAs) over time. ANIMALS: Sixteen healthy adult dogs. METHODS: Prospective, randomized controlled clinical trial. Dogs were randomized to receive 20 mg/kg of tylosin or a placebo capsule PO q12h for 7 days while undergoing daily fecal scoring. Fecal samples were collected on days 0, 7, 21, and 63. The microbiota was assessed using quantitative PCR and 16S rRNA gene sequencing. Unconjugated BAs were assessed using gas chromatography-mass spectrometry (GC-MS). RESULTS: Fecal scores were unchanged during placebo and tylosin administration. In the placebo group, no significant changes were observed in fecal microbiota or UBA concentrations. Day 7 samples from tylosin-exposed dogs exhibited decreased bacterial diversity (observed species, Chao1, Shannon, P < .001) characterized by decreases in anaerobes Fusobacteriaceae (linear discriminant analysis [LDA] score, 5.03) and Veillonellaceae (LDA score, 4.85). Primary UBA concentrations were increased at day 21 (median, [range]; 7.42, [0.67-18.77] µg/kg; P = .04) and day 63 (3.49 [0-28.43] µg/kg; P = .02) compared to day 0 (.14 [.03-1.19] µg/kg) in dogs receiving tylosin. At day 63, bacterial taxa were not significantly different compared to day 0, but the extent of microbial recovery was individualized. CONCLUSIONS AND CLINICAL IMPORTANCE: Tylosin causes fecal dysbiosis in healthy dogs with corresponding shifts in fecal UBAs. Changes did not uniformly resolve after discontinuation of tylosin.

Comparison of clinical, clinicopathologic, and histologic variables in dogs with chronic inflammatory enteropathy and low or normal serum 25-hydroxycholecalciferol concentrations.

BACKGROUND: The cause of low serum vitamin D concentrations in dogs with chronic inflammatory enteropathy (CIE) is not well understood. OBJECTIVE: Improve understanding of pathogenesis of low serum vitamin D concentrations in dogs with CIE by comparing several clinical, clinicopathologic, and histologic variables between CIE dogs with low and normal serum 25-hydroxyvitamin D concentrations (25[OH]D). ANIMALS: Fifteen dogs with CIE and low serum 25[OH]D concentrations; 15 dogs with CIE and normal serum 25(OH)D concentrations. METHODS: Prospective cohort study. Clinical and clinicopathologic variables were compared between groups. Correlations between serum 25(OH)D concentration and histopathologic variables were assessed. RESULTS: Dogs with CIE and low serum 25(OH)D concentrations had higher canine chronic enteropathy clinical activity index scores (P = .003), lower serum α-tocopherol (P < .001), cholesterol (P < .001), and albumin (P < .001) concentrations and higher serum C-reactive protein (P = .004) concentrations compared to CIE dogs with normal serum 25(OH)D concentrations. Serum concentrations of vitamin D-binding protein (VDBP) were not different between groups (P = .91). Duodenal morphologic and inflammatory histopathological scores (P = .002 and P = .004, respectively) and total histopathological scores in duodenum and combined duodenum and ileum negatively correlated with serum 25(OH)D concentration. CONCLUSIONS AND CLINICAL IMPORTANCE: The pathogenesis of low serum vitamin D concentrations in dogs with CIE is likely multifactorial. Fat malabsorption deserves further study in dogs with low serum vitamin D concentration and CIE. Loss of VDBP does not appear to be an important cause of low serum vitamin D concentration in dogs with CIE.

Lymphatic endothelial cell immunohistochemical markers for evaluation of the intestinal lymphatic vasculature in dogs with chronic inflammatory enteropathy.

BACKGROUND: Lymphatic endothelial cell (LEC) immunohistochemical markers have identified intestinal lymphatic vasculature abnormalities in humans with inflammatory bowel disease, but have not been used to evaluate intestinal lymphatic vasculature in a group of dogs with chronic inflammatory enteropathy (CIE). OBJECTIVES: To utilize LEC markers to identify and measure intestinal lymphatic vasculature in endoscopic biopsy samples of CIE dogs. To evaluate whether measured lymphatic vasculature variables correlate with serum albumin concentrations. ANIMALS: Twenty-four dogs with CIE; n = 13, serum albumin concentration <2.5 g/dL (CIE-protein-losing enteropathy [PLE]), n = 11, serum albumin concentration ≥2.5 g/dL (CIE-N). METHODS: Prospective study. Lymphatic endothelial cell immunolabeling with Prox-1 and LYVE-1 performed on endoscopic biopsy samples from 24 dogs with CIE. Duodenal and ileal villous lacteal width (VLW) and proprial mucosal lacteal width (MLW) were determined for each case and analyzed for correlation with serum albumin concentration. Lacteal dilatation scores using routine H&E histopathology were assessed for correlation with immunohistochemistry (IHC)-calculated VLW and MLW. RESULTS: Lower serum albumin concentrations were correlated with increased VLW (rho = -.4644; P = .02) and MLW (rho = -.6514; P < .001) in the ileum. Lymphatic endothelial cell IHC identified presumptive proprial mucosal lymphangiectasia in some dogs that was not recognized with routine H&E staining. Lacteal dilatation scores were correlated with VLW in duodenum (rho = .4634; P = .02) and ileum (rho = .5292; P = .008), but did not correlate with MLW. CONCLUSIONS AND CLINICAL IMPORTANCE: Lymphatic endothelial cell immunolabeling identified presumptive proprial mucosal lymphangiectasia in CIE dogs, particularly in the ileum of hypoalbuminemic dogs. Routine evaluation of villous lacteals likely underestimates abnormalities of the lymphatic vasculature in dogs with CIE.

Longitudinal assessment of microbial dysbiosis, fecal unconjugated bile acid concentrations, and disease activity in dogs with steroid-responsive chronic inflammatory enteropathy.

BACKGROUND: Mounting evidence from human studies suggests that bile acid dysmetabolism might play a role in various human chronic gastrointestinal diseases. It is unknown whether fecal bile acid dysmetabolism occurs in dogs with chronic inflammatory enteropathy (CE). OBJECTIVE: To assess microbial dysbiosis, fecal unconjugated bile acids (fUBA), and disease activity in dogs with steroid-responsive CE. ANIMALS: Twenty-four healthy control dogs and 23 dogs with steroid-responsive CE. METHODS: In this retrospective study, fUBA were measured and analyzed. Fecal microbiota were assessed using a dysbiosis index. The canine inflammatory bowel disease activity index was used to evaluate remission of clinical signs. This was a multi-institutional study where dogs with steroid-responsive CE were evaluated over time. RESULTS: The dysbiosis index was increased in dogs with CE (median, 2.5; range, -6.2 to 6.5) at baseline compared with healthy dogs (median, -4.5; range, -6.5 to -2.6; P = .002) but did not change in dogs with CE over time. Secondary fUBA were decreased in dogs with CE (median, 29%; range, 1%-99%) compared with healthy dogs (median, 88%; 4%-96%; P = .049). The percent of secondary fUBA in dogs with CE increased from baseline values (median, 28%; range, 1%-99%) after 2-3 months of treatment (median, 94%; range, 1%-99%; P = 0.0183). CONCLUSIONS AND CLINICAL IMPORTANCE: These findings suggest that corticosteroids regulate fecal bile acids in dogs with CE. Additionally, resolution of clinical activity index in dogs with therapeutically managed CE and bile acid dysmetabolism are likely correlated. However, subclinical disease (i.e., microbial dysbiosis) can persist in dogs with steroid-responsive CE.

Hepatic lipidosis: Clinical review drawn from collective effort.

Practical relevance: Hepatic lipidosis (HL) is the most common form of liver dysfunction in cats. If recognized early and treated appropriately, the prognosis is good; if not, the prognosis is grave. Clinical challenges: Distinguishing HL as idiopathic or secondary is critical since the presence of a concurrent disease affects the therapeutic plan and the prognosis. AUDIENCE: Despite the unique and severe nature of a cat's response to anorexia and the complexity of the metabolic changes underlying this condition, the clinical acumen and technical ability to effectively diagnose and treat HL are readily available to all small animal practitioners. Patient group: Although many species develop a 'fatty liver', the cat is one of relatively few species that suffer from HL. The classic presentation is that of an overweight cat that stops eating for days to weeks, losing weight in the process. Equipment: Abdominal ultrasound is frequently employed in the diagnostic work-up of an anorectic cat; ultrasonographic findings often support a presumptive diagnosis, provide samples for cytology and, perhaps most importantly, help identify concurrent conditions that must be addressed for therapeutic success. All of the equipment necessary for essential nutritional intervention in an anorectic cat is readily available and easily affordable. Evidence base: The material for this review draws heavily on a relatively large number of original studies, excellent reviews by recognized experts, and informative communication with experienced clinicians, hence the term 'collective effort'.

Evaluation of potential serum biomarkers of hepatic fibrosis and necroinflammatory activity in dogs with liver disease.

BACKGROUND: Serum interleukin 6 (IL-6), chemokine ligand 2 (CCL2), C-reactive protein (CRP), and the ratio of aspartate transaminase to alanine transaminase (AST:ALT) have been correlated with fibrosis and necroinflammatory activity in humans with various hepatopathies. HYPOTHESIS/OBJECTIVES: To determine whether increases in serum IL-6, CCL2, CRP, or AST:ALT were associated with moderate to severe fibrosis or necroinflammatory activity in dogs with various hepatopathies. ANIMALS: Forty-four client-owned dogs with clinical evidence of liver disease and 10 healthy purpose-bred dogs, all undergoing liver biopsies by laparoscopy or laparotomy. METHODS: Measurement of serum IL-6, CCL2, CRP, AST, and ALT before scheduled liver biopsy and evaluation of liver histopathology using the METAVIR scoring system used in human medicine, blinded to clinical presentation. RESULTS: Median serum IL-6 was approximately twice as high in dogs with high fibrosis scores (15.5 pg/mL; range, 1.4 to 235 pg/mL) compared to dogs with low fibrosis scores (7.6 pg/mL; range, 1.4 to 148.1 pg/mL), with marginal significance (P = .05). Median serum CCL2 was significantly higher in dogs with active necroinflammation (444 pg/mL; range, 144 to 896 pg/mL) compared to dogs without detectable necroinflammation (326 pg/mL; range, 59 to 1692 pg/mL; P = .008), but with considerable overlap between groups. Neither serum CRP nor AST:ALT ratios were significantly different based on fibrosis or necroinflammatory scores. CONCLUSIONS AND CLINICAL IMPORTANCE: Because of substantial variability among dogs, single measurements of IL-6 and CCL2 have limited diagnostic utility for identifying fibrosis or necroinflammation, respectively, in dogs with various chronic liver diseases. The value of these biomarkers should be explored further in monitoring response to treatment in individual dogs with chronic hepatopathies.

Bilious Vomiting Syndrome in Dogs: Retrospective Study of 20 Cases (2002-2012).

Bilious vomiting syndrome (BVS) is a condition historically associated with early morning vomiting of bile, but it is otherwise poorly characterized. The vomiting is thought to result from a reflux of duodenal fluid into the gastric lumen causing mucosal irritation. Medical records from Colorado State University Veterinary Teaching Hospital (CSUVTH) were searched for "canine" and "bilious vomiting syndrome" between 2002 and 2012. Visual inspection confirmed a diagnosis of BVS during the case history. The diagnosis remained BVS for the duration of the dog's contact with the hospital in 17 cases. Therapy involved frequent feedings, late evening meals, gastric acid reducers, prokinetics, and gastroprotectants. Twelve dogs improved with therapy. Five dogs did not improve or were lost to follow-up. The diagnosis of BVS was supplanted in three cases with gastric adenocarcinoma, dietary indiscretion, and hepatopathy. The patient most likely given a diagnosis of BVS would be a young, mixed-breed, castrated male dog with a chronic history of vomiting bile. Response to therapy suggests abnormal gastrointestinal motility, local gastritis, gastric pH, or stimulation of the emetic center may be important factors in BVS. Dogs diagnosed with BVS rarely received a diagnostic evaluation sufficient to qualify it as a diagnosis of exclusion.

Vitamin E supplementation fails to impact measures of oxidative stress or the anaemia of feline chronic kidney disease: a randomised, double-blinded placebo control study.

This study was designed to test the hypothesis that supplementation with vitamin E, an antioxidant, in cats with chronic kidney disease (CKD), would reduce oxidative stress and its impact on RBC membrane fragility, resulting in these cats maintaining a greater packed cell volume (PCV) compared with CKD cats not receiving supplementation. Thirty-six cats with CKD were randomly assigned to receive either daily vitamin E or a placebo for 3 months in a double-blinded study design. History and physical examination, blood pressure, complete blood count (CBC), PCV, biochemical profile and urinalysis (UA) were determined. Parameters of oxidative stress and osmotic fragility were measured. Cats were administered vitamin E or placebo once daily for 3 months. Cats were then reassessed and the diagnostics were repeated. Twenty-four cats completed the study, 11 in the vitamin E group and 13 in the placebo group. There were no significant differences between the two groups at the start, or upon completion of the study with regard to biochemical parameters, oxidative stress, erythrocyte osmotic fragility or PCV. None of these parameters changed significantly in either group over the treatment period. Daily supplementation with 30 IU of vitamin E did not affect the measures of oxidative stress or the anaemia seen in cats with CKD.

Stem cell therapy in cats with chronic enteropathy: a proof-of-concept study.

OBJECTIVES: The current treatment of cats with chronic enteropathy frequently includes use of a prescription diet and daily medication administration, with the potential for side effects or problems with owner compliance, and may still result in treatment failure in some cases. The objective of this study was to determine if stem cell therapy was a safe and viable treatment in cases of feline chronic enteropathy. METHODS: Allogeneic adipose-derived feline mesenchymal stem cells (fMSC) were used to treat seven cats with diarrhea of no less than 3 months' duration, while four cats with a similar clinical condition received placebo, in a blinded manner. Three additional cats were treated with an identical fMSC protocol, but owners were not blinded to the treatment. Owners completed a questionnaire characterizing clinical signs both before entering the study and 2 weeks following the second of two fMSC or placebo treatments. Owners were also surveyed for similar input by email 1-2 months later before being unblinded to their cat's study group. Besides the fMSC or placebo treatment, no other changes were made in diet, supplement or medication administration during the study. RESULTS: No adverse reactions or side effects were attributed to the fMSC therapy in any of the cats. Owners of 5/7 fMSC-treated cats reported significant improvement or complete resolution of clinical signs, while the owner of the remaining two cats reported modest but persistent improvement. Owners of placebo-treated cats reported no change or worsening of clinical signs. Of the owners not blinded to the treatment, one reported marked improvement, one reported no change and one was lost to follow-up. CONCLUSIONS AND RELEVANCE: Although allogeneic adipose-derived fMSC therapy appears to be a safe and potentially effective treatment for cats suffering from chronic enteropathy, these preliminary results require significant follow-up study.

Open-label trial of a multi-strain synbiotic in cats with chronic diarrhea.

This study was designed to test the hypothesis that in cats with chronic diarrhea the daily administration of a proprietary synbiotic (Proviable-DC) would result in an improvement in stool character, as assessed by the owner. Adult cats with chronic diarrhea were recruited for the study and screened for systemic diseases. Fecal flotation, wet mount, immunofluorescence assay (IFA) for Giardia and Cryptosporidium species, and Tritrichomonas species polymerase chain reactions (PCRs) were used to screen for intestinal parasitism. The synbiotic was administered for 21 days; otherwise, no changes were made to ongoing treatment(s) or diet. The severity of the diarrhea was assessed using a standardized fecal scoring system and the owner's subjective perception before, and after, supplementation. The mean fecal score for the 53 cats completing the study decreased from 6.0 to 4.4, representing a significantly (P <0.001) firmer stool character. Seventy-two percent of owners perceived an improvement in their cat's diarrhea following a 21-day course of synbiotic supplementation.

Hepatic dysfunction.

This article reviews the common pathophysiology that constitutes hepatic dysfunction, regardless of the inciting cause. The systemic consequences of liver failure and the impact of this condition on other organ systems are highlighted. The diagnostic tests available for determining the cause and extent of liver dysfunction are outlined, treatment strategies aimed at supporting hepatic health and recovery are discussed, and prognosis is briefly covered. The article emphasizes the fact that because of the central role of the liver in maintaining normal systemic homeostasis, hepatic dysfunction cannot be effectively addressed as an isolated entity.

Comparison of tissue oxygen saturation in ovariohysterectomized dogs recovering on room air versus nasal oxygen insufflation.

OBJECTIVE: To compare tissue oxygen saturation in ovariohysterectomized dogs recovering postoperatively on room air versus nasal oxygen insufflation. DESIGN: Prospective clinical study. SETTING: University teaching hospital. ANIMALS: Twenty dogs undergoing ovariohysterectomy. INTERVENTIONS: Dogs were randomized to breathe either room air or 100 mL/kg/min of nasal oxygen insufflation for 2 hours postoperatively. Tissue oxygen saturation (StO(2)) was evaluated at 2 mm and 20 mm lateral to the surgical incision, as well as in the inguinal region using a noninvasive tissue oximeter. MEASUREMENTS AND MAIN RESULTS: In dogs recovered on nasal oxygen insufflation (n = 10), tissue oxygen saturation was significantly higher--20 mm from the surgical site (88.44 ± 2.50%, P = 0.02) and in the inguinal region (83.56 ± 1.91%, P = 0.032)-- compared to dogs recovered on room air (n = 10, 79.11% ± 2.50 and 77.12% ± 1.91, respectively). CONCLUSIONS: In ovariohysterectomized dogs, oxygen supplementation for 2 hours postoperatively improves tissue oxygen saturation 20 mm adjacent to the linea alba and in the inguinal region. Oxygen supplementation in postoperative dogs is an inexpensive and easily applicable method to improve tissue oxygen saturation.

Assessment of oxidative stress in leukocytes and granulocyte function following oral administration of a silibinin-phosphatidylcholine complex in cats.

OBJECTIVE: To determine the effect of oral administration of a silibinin-phosphatidylcholine complex (SPC) on oxidative stress in leukocytes and granulocyte function in healthy cats. ANIMALS: 10 purpose-bred adult cats. PROCEDURES: Cats were administered SPC (10 mg/kg/d) orally for 5 days; blood samples were collected prior to and immediately after the 5-day treatment period. Leukocytes were incubated with monochlorobimane for detection of reduced glutathione (GSH) via flow cytometry. Leukocytes were also incubated with dihydrorhodamine 123 and mixed with Escherichia coli conjugated to a fluorescent marker to measure E coli phagocytosis and the subsequent oxidative burst via flow cytometry. Activities of the antioxidant enzymes superoxide dismutase and glutathione peroxidase, along with the reduced glutathione-to-oxidized glutathione (GSH:GSSG) ratio and a measure of lipid peroxidation (malondialdehyde concentration [micromol/L of blood]), were measured spectrophotometrically. RESULTS: The mean fluorescence intensity (MFI), representing GSH content, increased significantly in feline lymphocytes and granulocytes following 5 days of oral administration of SPC. Mean +/- SD lymphocyte MFI significantly increased from 27.8 +/- 9.0 to 39.6 +/- 6.7, and the granulocyte MFI increased from 508.6 +/- 135.6 to 612.1 +/- 122.9. Following 5 days of SPC administration, the percentage of phagocytic cells that were responding optimally significantly increased (from 37 +/- 11.8% to 45 +/- 17.5%). Other measures of oxidative stress did not change significantly. CONCLUSIONS AND CLINICAL RELEVANCE: In cats, oral administration of supplemental SPC appears to increase granulocyte GSH content and phagocytic function, both of which would be potentially beneficial in cats with diseases associated with oxidative stress.