Vitamin E supplementation in canine atopic dermatitis: improvement of clinical signs and effects on oxidative stress markers

A Randomized Controlled Trial to Evaluate the Impact of a Novel Probiotic and Nutraceutical Supplement on Pruritic Dermatitis and the Gut Microbiota in Privately Owned Dogs

Pruritic dermatitis (PD) is a common presentation of canine allergic skin diseases, with diversity in severity and treatment response due to complex etiopathogenesis. Evidence suggests the gut microbiota (GM) may contribute to the development of canine allergies. A 10-week double-blind randomized controlled trial evaluated a novel probiotic and nutraceutical blend (PNB) on clinical signs of skin allergy, health measures, and the GM of privately owned self-reported pruritic dogs. A total of 105 dogs were enrolled, with 62 included in pruritus and health analysis and 50 in microbiome analysis. The PNB supported greater improvement of owner-assessed clinical signs of PD at week 2 than the placebo (PBO). More dogs that received the PNB shifted to normal pruritus (digital PVAS10-N: <2) by week 4, compared to week 7 for the PBO. While a placebo effect was identified, clinical differences were supported by changes in the GM. The PNB enriched three probiotic bacteria and reduced abundances of species associated with negative effects. The PBO group demonstrated increased abundances of pathogenic species and reduced abundances of several beneficial species. This trial supports the potential of the PNB as a supplemental intervention in the treatment of PD; however, further investigation is warranted, with stricter diagnostic criteria, disease biomarkers and direct veterinary examination.

Evaluation of antioxidant status and lipid peroxidation in dogs with myxomatous mitral valve degeneration stage B1

Myxomatous mitral valve degeneration (MMVD) is the most common naturally occurring heart disease in dogs. There is a lack of data on antioxidant status and oxidative damage in dogs with MMVD stage B1 according to the American College of Veterinary Internal Medicine (ACVIM B1). The aim of this study was to investigate antioxidant status (plasma vitamin E, lipid-standardized vitamin E (LS-VitE), antioxidant capacity of lipid-(ACL) and water-soluble antioxidants, whole blood glutathione peroxidase and erythrocyte superoxide dismutase), and lipid peroxidation [malondialdehyde (MDA)] in dogs with MMVD ACVIM B1. Serum cholesterol and triglyceride concentrations were measured to calculate LS-VitE. Fourteen dogs with MMVD ACVIM B1 and 12 control dogs were included in the study. Dogs with MMVD had significantly higher vitamin E, ACL, MDA, and cholesterol concentrations and significantly higher LS-VitE values than control dogs. No significant correlations between MDA and antioxidant parameters were determined in either group. In conclusion, oxidative damage to lipids is already present and the antioxidant status is altered but not depleted in dogs with MMVD ACVIM B1. The antioxidant response to increased oxidative damage consists mainly of the activation of fat-soluble antioxidants. Further research is needed to evaluate the efficacy and targets of early antioxidant supplementation to prevent or ameliorate oxidative stress and mitigate disease progression in dogs with early-stage MMVD.

Evidence-base for the beneficial effect of nutraceuticals in canine dermatological immune-mediated inflammatory diseases - A literature review

BACKGROUND

Immune-mediated inflammatory diseases (IMIDs) are associated with an abnormal immune response, resulting in a disturbed homeostasis and chronic inflammation. Most canine dermatological IMIDs (cDIMIDs), such as allergies, autoimmune and immune-mediated diseases, require long-term treatment with immunosuppressive drugs with potential adverse effects. In general, nutraceuticals are thought to be safe. As a result, there is a tendency for the more frequent use of nutraceuticals in veterinary medicine.

OBJECTIVES

The aim of this review was to present evidence-based proof for the use of various nutraceuticals in the treatment of cDIMIDs and, where possible, to provide conclusions to guide their use in veterinary dermatological practice.

METHODS

A comprehensive literature search on common cDIMIDs and nutraceuticals was performed. Only peer-reviewed articles published in English and related to the study topic were included. A total of 64 eligible publications were classified in five categories based on study design and substantively assessed on additional criteria such as standardisation of diets and number of included animals. For final appraisal, classification of major, minor or no evidence was used whereby efficacy was based on clinical outcome measurements.

CONCLUSIONS

Minor evidence for the beneficial use of several nutraceuticals, including essential fatty acids, niacinamide and probiotics, was found for treatment of specific cDIMIDs. These nutraceuticals may improve clinical signs or reduce the required dose of concurrent medication (e.g. drug-sparing effect) in some dogs. Some nutraceuticals also may be used for long-term maintenance therapy. Despite some promising findings, major evidence for the use of nutraceuticals in cDIMIDs is lacking, warranting further research.

Dry food affects the oxidative/antioxidant profile of dogs

BACKGROUND

Including adequate concentrations of antioxidants in dog diets has been recommended to reduce their vulnerability to the action of free radicals and reactive oxygen species (ROS). Oxidative stress in dogs has been associated with a wide range of diseases and disorders, as well as with ageing. There are few reports about the influence of diet on dog's antioxidant profile and oxidative stress.

OBJECTIVE

The objective of this study was to evaluate the effect of four types of dry dog food on the oxidative/antioxidant profile of dogs.

METHODS

Six Beagle dog males were used. The study included four experimental diets (dry foods A-D). Each dry food was supplied for 5 weeks to all dogs, for a total of 24 weeks, including an adaptation week between one food and another. For each dry dog food, the total phenolic content (TPC), total antioxidant capacity (TAC) and cytotoxicity were evaluated. Each week, a blood sample was collected to measure ROS and TAC of plasma. A crossover repeated measures design was used. Mixed models were adjusted, and means were compared using the Tukey test.

RESULTS

Food A had the highest values for TPC and TAC. Food C had the lowest levels of ROS, whereas food B had the highest TAC in the blood plasma. The dog had a significant influence on the redox state of its blood plasma, even when the same dog was fed the different dry foods.

CONCLUSION

Dry dog food influences the oxidative/antioxidant profile of dog's blood plasma; however, this seems to be unrelated to the antioxidant profile of the food.

Randomized, double-blind, placebo-controlled clinical trial measuring the effect of a dietetic food on dermatologic scoring and pruritus in dogs with atopic dermatitis

Background

Canine atopic dermatitis (AD) is a common condition that often requires multimodal therapy. Including a diet in the multimodal management of AD may reduce medication doses, saving pet owners money and reducing side effects. The objective of this randomized, double-blind, placebo-controlled clinical trial was to determine if a diet fortified in antioxidants, polyphenols, and omega-3 fatty acids can reduce the clinical signs of AD. Forty client-owned dogs with AD were enrolled in the study and assigned to either an enriched diet (diet B) or control diet (diet A) for 60-days. CADESI-4 index scores and owner-reported pruritus scores were measured periodically.

Results

Total CADESI-4 index scores for dogs eating diet B were lower on day 60 compared to baseline (P = 0.003). There was no statistical difference in scores for dogs eating diet A over a 60-day period. Diet B dogs had 25 and 49% reductions in CADESI-4 index scores on days 30 and 60, respectively (P = 0.0007) while diet A had no change over the study period. When comparing the percent change in owner-reported pruritus scores, diet B also performed better than diet A. By day 60, owners feeding diet B to their dogs reported a significant reduction (P < 0.0001) of 46.4% in itching, while those on diet A reported a 26.8% reduction, which was not statistically significant (P = 0.08).

Conclusions

These study results demonstrate feeding a diet enriched with ingredients to improve skin health and reduce inflammation improves the clinical signs of AD in dogs.

A novel therapeutic diet can significantly reduce the medication score and pruritus of dogs with atopic dermatitis during a nine month controlled study

Background

Canine atopic dermatitis (cAD) is a common chronic relapsing pruritic skin disease for which management commonly relies on life‐long use of immunomodulatory drugs. A number of the medications used are associated with adverse effects and the potential for complications during long‐term use.

Hypothesis

The goal of the study was to determine if a complete and balanced diet formulated for therapeutic benefit could contribute towards management of cAD. We hypothesised that the diet would reduce pruritus while also reducing the requirement for medication during the study period.

Animals, materials and methods

Forty privately owned dogs, having undergone a comprehensive diagnosis for cAD, were randomly allocated to two groups, each group being fed one of two diets (test or control) for up to nine months. We assessed pruritus, Canine Atopic Dermatitis Extent and Severity Index‐(4th iteration) and medication score, the latter reflecting the medication required to maintain a satisfactory quality of life for the animal.

Results

Both diets were well‐accepted and ‐tolerated. There was a significant improvement in the pruritus score after three months of feeding the therapeutic diet (P = 0.0001). No such improvement was observed at any time point in the group of dogs given the control diet. There was a reduced drug requirement for dogs receiving the therapeutic diet after three months (P = 0.058), and that decrease was significant at six months (P = 0.021) and nine months (P = 0.018). No improvement was seen at any time point in the control group.

Conclusion

The results suggest that a novel therapeutic diet can assist in the management of cAD by helping to control pruritus and reducing reliance on medication.

Roles of plant-based ingredients and phytonutrients in canine nutrition and health

Dogs possess the ability to obtain essential nutrients, established by the Association of American Feed Control Officials (AAFCO), from both animal‐ and plant‐based ingredients. There has been a recent increase in the popularity of diets that limit or completely exclude certain plant‐based ingredients. Examples of these diets include ‘ancestral’ or ‘evolutionary’ diets, raw meat‐based diets and grain‐free diets. As compared to animal sources, plant‐derived ingredients (including vegetables, fruits, grains, legumes, nuts and seeds) provide many non‐essential phytonutrients with some data suggesting they confer health benefits. This review aims to assess the strength of current evidence on the relationship between the consumption of plant‐based foods and phytonutrients (such as plant‐derived carotenoids, polyphenols and phytosterols) and biomarkers of health and diseases (such as body weight/condition, gastrointestinal health, immune health, cardiovascular health, visual function and cognitive function) from clinical trials and epidemiological studies. This review highlights the potential nutritional and health benefits of including plant‐based ingredients as a part of balanced canine diets. We also highlight current research gaps in existing studies and provide future research directions to inform the impact of incorporating plant‐based ingredients in commercial or home‐prepared diets.

Successful nutritional control of scratching and clinical signs associated with adverse food reaction: A randomized controlled COSCAD'18 adherent clinical trial in dogs in the United States

Background

Adverse reactions to food are a common dermatological condition in dogs, requiring nutritional intervention using a novel or hydrolysate protein‐based food.

Objective

To evaluate a therapeutic food containing egg and phytonutrients in dogs with food allergies using an activity monitor and core outcome set for canine atopic dermatitis (COSCAD'18) guidelines and in a controlled double‐masked, multicenter, prospective clinical trial.

Animals

Adult dogs with a history of adverse food reaction as diagnosed by a food elimination trial were recruited from general practices.

Methods

After a 21‐day baseline period, dogs were randomized to test or positive control (hydrolyzed protein) food for 21 days. Owner (pruritus visual analog score [PVAS], coat quality, food acceptance, and satisfaction) and veterinarian (canine atopic dermatitis lesion index [CADLI], physical examination) assessments were completed on days 0, 21, and 42. Dogs wore a collar‐mounted activity monitor to record scratching and shaking behavior throughout the study. Statistical analysis included within‐group comparison to baseline and between‐group comparison at study end using a significance threshold of alpha = 0.05.

Results

At the end of the treatment period, all results were similar between groups for CADLI, PVAS, owner satisfaction, activity, and questionnaire data. Scores for hair dullness, brittleness, amount of dandruff, feces quality, and food acceptance were positive and not statistically different between groups.

Conclusions and Clinical Importance

The therapeutic test food was well‐accepted and efficacious in managing signs of adverse reactions to food compared to baseline as well as compared to the positive control food.

Successful nutritional control of scratching and clinical signs associated with adverse food reaction: A randomized controlled COSCAD'18 adherent clinical trial in dogs in the United Kingdom

Background

Adverse reactions to food are a common dermatological condition in dogs, requiring nutritional intervention using novel or hydrolysate protein‐based foods.

Objective

To evaluate a therapeutic food containing egg and phytonutrients in dogs with food allergies using an activity monitor and core outcome set for canine atopic dermatitis (COSCAD'18) in a controlled double‐masked, multicenter, prospective clinical trial.

Animals

Adult dogs with a history of adverse food reaction as diagnosed by a food elimination trial were recruited from general practices.

Methods

After a 21‐day baseline period, dogs were randomized to test or positive control (hydrolyzed protein) food for 21 days. Owner (pruritus visual analog score [PVAS], coat quality, food acceptance, and satisfaction) and veterinarian (canine atopic dermatitis lesion index [CADLI], physical examination) assessments were completed on days 0, 21, and 42. Dogs wore a collar‐mounted activity monitor to record sleep, scratching, and shaking behavior throughout the study. Statistical analysis included within‐group comparison to baseline and between‐group comparison at study end using a significance threshold of alpha = 0.05.

Results

At the end of the treatment period, all results were similar between groups for CADLI, PVAS, owner satisfaction, activity, and questionnaire data. Scores for hair dullness, brittleness, amount of dandruff, feces quality, and food acceptance were positive and were not statistically different between groups.

Conclusions and Clinical Importance

The therapeutic test food was well‐accepted and efficacious in managing signs of adverse reactions to food compared to baseline as well as compared to the positive control food.

A proposed medication score for long-term trials of treatment of canine atopic dermatitis sensu lato

BACKGROUND

The use of concurrent medications is necessary in trials of treatment of canine atopic dermatitis. Our aim was to use the best available evidence to construct and then to validate a medication score (MS) formula that will estimate the impact of concurrent medications on trial outcomes.

METHODS

Trials of 15 interventions were scrutinized to find those that were consistent in terms of specific medication, administration route and dosage regimen. A MS was constructed in five steps, starting from assigning a score of 1 for each day on oral prednisone, prednisolone or methylprednisolone at 0.5-1.0 mg/kg. The MS score was validated using the clinical records of 35 dogs with atopic dermatitis that had been treated for a period of 12 ± 2 weeks with six of these medications and compared with a previously published non-validated MS.

RESULTS

A MS could be assigned to eight treatments, six of which had been administered to the 35 dogs. A positive correlation was seen with the previously published MS and a negative correlation with changes in lesional and pruritus scores.

CONCLUSION

This MS may be a useful tool in new studies evaluating the efficacy of treatments in canine atopic dermatitis.

Vitamin E in Atopic Dermatitis: From Preclinical to Clinical Studies

BACKGROUND

Oxidative stress and inflammation are some of the proposed mechanisms involved in the pathogenesis of atopic dermatitis (AD). Current pharmacotherapeutic approaches are effective yet they are not without adverse effects. Vitamin E has great potential as an adjunctive treatment for AD owing to its antioxidant and anti-inflammatory bioactivities.

SUMMARY

This review article summarizes the current available evidence from cellular, animal and clinical studies on the relationship between vitamin E and AD. The future prospects of vitamin E are also discussed. Vitamin E in practice does not show any toxicity to humans within a range of reasonable dosage. Albeit rarely, vitamin E as a contact allergen should be considered. Collectively, this review envisaged vitamin E as an adjunctive treatment for AD patients. Future research on the distinct effects of different vitamin E isoforms as well as their delivery system in skin disorders is needed.

The Effect of Atopic Dermatitis and Diet on the Skin Transcriptome in Staffordshire Bull Terriers

Canine atopic dermatitis (CAD) has a hereditary basis that is modified by interactions with the environment, including diet. Differentially expressed genes in non-lesional skin, determined by RNA sequencing before and after a dietary intervention, were compared between dogs with naturally occurring CAD (n = 4) and healthy dogs (n = 4). The dogs were fed either a common commercial heat-processed high carbohydrate food (kibble diet) (n = 4), or a non-processed high fat food (raw meat-based diet) (n = 4). At the end of the diet intervention, 149 differentially expressed transcripts were found between the atopic and healthy dogs. The main canonical pathways altered by the dysregulation of these genes were angiopoietin signaling, epidermal growth factor signaling, activation of angiogenesis, and alterations in keratinocyte proliferation and lipid metabolism. On the other hand, 33 differently expressed transcripts were found between the two diet groups, of which 8 encode genes that are annotated in the current version of the dog genome: immunoglobulin heavy constant mu (IGHM), immunoglobulin lambda-like polypeptide 5 (IGLL5), B-cell antigen receptor complex-associated protein beta chain (CD79B), polymeric immunoglobulin receptor (PIGR), cystathionine β-synthase (CBS), argininosuccinate synthase 1 (ASS1), secretory leukocyte peptidase inhibitor (SLPI), and mitochondrial ribosome recycling factor (MRRF). All genes were upregulated in the raw diet group. In conclusion the findings of this study suggest alterations in lipid and keratinocyte metabolism as well as angiogenesis in the skin of atopic dogs. Additionally, a possible enhancement of innate immunity and decrease in oxidative stress was seen in raw food fed dogs, which could have an important role in preventing hypersensitivities and disturbed immunity at young age.

Topical effect of a specific spot-on treatment made of natural ingredients in rabbits (Oryctolagus cuniculus) with skin problems: A pilot study

Background and Aim:

Rabbits often experience skin diseases. The beneficial effects of plant extracts and essential oils are well known in other species, but the properties of these natural ingredients have not been evaluated in rabbits in vivo. The objective of the current study was to evaluate the effect of a topical, commercial solution made of essential oils, plant-extracted polyunsaturated fatty acids, and Vitamin E on rabbits suffering from skin problems.

Materials and Methods:

Thirty New Zealand rabbits (no sex distinction) were included in this study, with an average weight of 2–3 kg. The rabbits were divided into two groups: The first group was treated with a topical solution made from natural ingredients, and the second was a control group. The rabbits’ hair and skin conditions were evaluated on days 1, 14, 28, and 35 after treatment. Data were analyzed using a Kruskal–Wallis range test.

Results:

Significant differences were determined in terms of glossy hair variability on days 28 and 35 (p≤0.0001). On days 14-35, hair loss was determined to have reduced (p=0.001), and flaking and odor improved in the treatment group, showing increased scores and significant differences (p=0.0001). By contrast, the control group showed stable overall skin and hair score and an increase in the dryness score.

Conclusion:

The topical application of essential oils and polyunsaturated fatty acids with Vitamin E was able to improve hair shine and skin hydration and reduce flaking, bad odor, and hair loss, improving the general, and cutaneous aspect of rabbits.

Impact of Nutritional Supplementation on Canine Dermatological Disorders

Nutritional supplements, also known as complementary feeds, are products administered with the aim of furnishing health benefits, regardless of nutritional needs. They have been used since ancient times in veterinary dermatology, and a number of studies have focused on investigating the health benefits of some ingredients found in commercially available complementary feed for dogs. The aim of this paper is to review the literature available on the use of nutritional supplementation for the management of canine skin diseases, critically appraising the clinical efficacy of such interventions and summarizing the current state of knowledge. This review highlights how these feeds can be considered useful in the management of dermatological disorders and outlines their beneficial effects in the prevention of dietary deficiencies and treatment of diseases, alone, or in addition to conventional pharmacological therapy. In recent years, nutritional supplements have found increasing potential application in veterinary medicine, and the scientific proofs of their beneficial effects are described in this review.

Non-controlled, open-label clinical trial to assess the effectiveness of a dietetic food on pruritus and dermatologic scoring in atopic dogs

BACKGROUND

Canine atopic dermatitis (AD) is a common skin disease. The goal of this study was to evaluate food designed to improve skin barrier function and lower inflammation to reduce pruritus and clinical severity in client-owned atopic dogs. The food contained an antioxidant blend to reduce oxidative stress, plant polyphenols to stabilize mast cells, and polyunsaturated fatty acids to improve skin health and reduce inflammation.

RESULTS

Seventeen dogs were included in the analysis. Initially 48 adult atopic dogs were enrolled and exclusively fed a dermatologic food for 8 weeks in a non-controlled, open-label study. Thirty-one dogs were excluded for the following reasons: oral and topical medication changes (n = 17), missing data (n = 4), fatty acid supplementation (n = 3), food refusal (n = 3), dropped out (n = 3), and owner concerns (n = 1). Using a scale from 0 (normal) - 4 (severe), veterinarians evaluated the presence and severity of clinical signs of atopy at weeks 0, 4, and 8. Pet owners also rated their pet's clinical signs of atopy on a scale from 0 (not present) - 10 (present continuously) at weeks 0, 4, and 8. Compared with initial baseline scores (median 19, range 3-69), the total veterinarian scores were significantly lower at weeks 4 (median 11, range 1-15) and 8 (median 7, range 3-46) (p < 0.05). Similarly, owner assessments showed significant improvements in the least squares mean (LSM) from baseline to 4 weeks (itching, redness, licking, and scratching) continuing to 8 weeks (itching, redness, and scratching) (p < 0.05).

CONCLUSIONS

In this open, non-controlled study evaluating a dermatologic diet in seventeen client-owned dogs, owner and veterinarian assessments showed statistically significant reductions in clinical scores designed to measure severity of atopic dermatitis. While these results show promise for the management of canine atopic dermatitis, controlled clinical trials are also needed to affirm our findings.

Therapies in Canine Atopic Dermatitis: An Update

Canine atopic dermatitis (AD) is one of the most common inflammatory skin diseases in dogs. The pathogenesis is complex and not completely understood. Many therapeutic options are available; however, because of cost, side effects, or a long lag phase, new compounds are constantly produced. This article provides a comprehensive review of the latest compounds for the treatment of canine AD. In addition, a brief review of new studies on conventional medications is provided. For a successful long-term therapeutic approach, it is important to considerate the status of the disease, as well as the patients' and their owners' needs.

Selected serum oxidative stress biomarkers in dogs with non-food-induced and food-induced atopic dermatitis

BACKGROUND

Oxidative stress (OS) has been shown to be involved in the pathogenesis of human and canine atopic dermatitis (AD) through several distinct mechanisms. Selected serum biomarkers of OS (sbOS) have been validated in normal dogs and studied in several canine diseases. To the best of the authors' knowledge, the sbOS evaluated in this study have not previously been described in canine AD.

HYPOTHESIS/OBJECTIVES

The aims of the study were to evaluate a panel of sbOS in dogs with food-induced (FIAD) and non-food-induced (NFIAD) AD: cupric reducing antioxidant capacity (CUPRAC), ferrous oxidation-xylenol orange (FOX), ferric reducing ability of the plasma (FRAP), paraoxonase-1 (PON1), trolox equivalent antioxidant capacity (TEAC) and serum total thiol (THIOL). The aim was to compare these metabolites with those in healthy control dogs, and to correlate sbOS with validated pruritus and CADESI-04 severity scales in dogs with AD.

ANIMALS

Forty six healthy, nine NFIAD and three FIAD client-owned dogs were included.

METHODS

The study was designed as a cohort study.

RESULTS

There were significant differences in atopic dogs when compared to healthy dogs for all of the sbOS analysed.

CONCLUSIONS AND CLINICAL RELEVANCE

These findings suggest that OS could play a role in the pathogenesis of canine NFIAD and FIAD. In addition, the evaluation of sbOS could be useful for precision medicine to help to detect atopic dogs that might benefit from antioxidant-targeted therapies.

Glutathione Peroxidase Activity, Plasma Total Antioxidant Capacity, and Urinary F2- Isoprostanes as Markers of Oxidative Stress in Anemic Dogs

Background

Oxidative stress plays a role in the pathophysiology of several diseases and has been documented as a contributor to disease in both the human and veterinary literature. One at‐risk cell is the erythrocyte, however, the role of oxidative stress in anemia in dogs has not been widely investigated.

Hypothesis/Objective

Anemic dogs will have an alteration in the activity of glutathione peroxidase (GPx), a decrease in of total antioxidant capacity (TAC), and an increased concentration of urinary 15‐F₂‐isoprostanes (F₂‐IsoP) when compared to healthy dogs.

Animals

40 client‐owned dogs with anemia (PCV <30%) age‐matched to 40 client‐owned healthy control dogs.

Methods

Prospective, cross‐sectional study. Whole blood GPx activity, plasma TAC, and urinary F₂‐isoprostane concentrations were evaluated in each dog and compared between groups.

Results

Anemic dogs had significantly lower GPx activity (43.1 × 10³ +/‐ 1.6 × 10³ U/L) than did dogs in the control group (75.8 × 10³ +/‐ 2.0 × 10³ U/L; P < 0.0001). The GPx activity in dogs with hemolysis (10³ +/‐ 0.8 × 10³ U/L) was not significantly different (P = 0.57) than in dogs with nonhemolytic anemia (43.5 × 10³ +/‐ 1.1 × 10³ U/L). The TAC concentrations (P = 0.15) and urinary F₂‐isoprostanes (P = 0.73) did not significantly differ between groups.

Conclusions and Clinical Importance

Glutathione peroxidase activity was significantly decreased in anemic dogs indicating oxidative stress. Additional studies are warranted to determine if antioxidant supplementation would improve survival and overall outcome as part of a therapeutic regimen for anemic dogs.

Vitamin E plasma kinetics in swine show low bioavailability and short half-life of -α-tocopheryl acetate

Vitamin E is important for animal production because of its effects on health and product quality, but the amount and form required remains controversial. Our objective was to quantify the absolute bioavailability of oral -α-tocopheryl acetate (α-TAc) in swine (22 ± 1 kg and 8 wk old, fitted with jugular catheters) adapted to a diet supplemented with 75 mg/kg -α-TAc; 75 mg/kg was chosen because this level represents the nonweighted average inclusion level in piglet diets across Western key swine-producing countries. For this, a 350-g test meal (6% fat) was supplied at time 0 containing 75 mg deuterated (D9) -α-TAc to 9 animals, and 8 animals received an intravenous () dose containing deuterated (D6) RRR-α-tocopherol (α-T) at one-eighth the oral dose and a test meal without supplemental vitamin E. Plasma samples (12 to 13 per animal) were obtained at incremental intervals over 75 h for analysis of deuterated α-T using liquid chromatography-tandem mass spectrometry. Surprisingly, the i.v. dose rapidly disappeared from plasma and then reappeared. The half-life for this first peak was only 1.7 ± 0.3 min. The second peak had an appearance rate (Ka) of 0.10 ± 0.06 d and a half-life of 5.9 ± 1.2 h. Oral dosing resulted, after a lag of 56 min, in a Ka of 0.91 ± 0.21 d and a half-life of 2.6 ± 0.8 h. The bioavailability for oral α-TAc was 12.5%, whereas the area under the curve was only 5.4%. This low bioavailability, small area under the curve, and short half-life are likely because of various factors, that is, the use of only 6% fat in the diet, the use of the acetate ester and , and the high dose relative to requirements. In conclusion, i.v. dosed vitamin E shows both a rapid and a very slow pool, whereas orally dosed vitamin E shows a single slow pool. The oral material has a very short half-live (44% of i.v. or 2.6 h), low bioavailability (12.5%), and a very small area under the curve (5.4%), bringing into question the efficacy of typical doses of vitamin E in swine diets for alleviating oxidative stress.

Oxidative Stress in Atopic Dermatitis

Atopic dermatitis (AD) is a chronic pruritic skin disorder affecting many people especially young children. It is a disease caused by the combination of genetic predisposition, immune dysregulation, and skin barrier defect. In recent years, emerging evidence suggests oxidative stress may play an important role in many skin diseases and skin aging, possibly including AD. In this review, we give an update on scientific progress linking oxidative stress to AD and discuss future treatment strategies for better disease control and improved quality of life for AD patients.

Treatment of canine atopic dermatitis: 2015 updated guidelines from the International Committee on Allergic Diseases of Animals (ICADA)

Background

In 2010, the International Task Force on Canine Atopic Dermatitis (now International Committee on Allergic Diseases of Animals, ICADA) published the first consensus guidelines for the treatment of atopic dermatitis (AD) in dogs. This is the first 5-year minor update of this document.

Results

The treatment of acute flares of AD should involve the search for, and then elimination of, the cause of the flares, bathing with mild shampoos, and controlling pruritus and skin lesions with interventions that include topical and/or oral glucocorticoids or oclacitinib. For chronic canine AD, the first steps in management are the identification and avoidance of flare factors, as well as ensuring that there is adequate skin and coat hygiene and care; this might include more frequent bathing and possibly increasing essential fatty acid intake. The medications currently most effective in reducing chronic pruritus and skin lesions are topical and oral glucocorticoids, oral ciclosporin, oral oclacitinib, and, where available, injectable recombinant interferons. Allergen-specific immunotherapy and proactive intermittent topical glucocorticoid applications are the only interventions likely to prevent or delay the recurrence of flares of AD.

Conclusions

This first 5-year minor update of the international consensus guidelines for treatment of AD in dogs further establishes that the treatment of this disease is multifaceted, and that interventions should be combined for a proven (or likely) optimal benefit. Importantly, treatment plans are likely to vary between dogs and, for the same dog, between times when the disease is at different stages.

Electronic supplementary material

The online version of this article (doi:10.1186/s12917-015-0514-6) contains supplementary material, which is available to authorized users.