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.

How Can We Advance Integrative Biology Research in Animal Science in 21st Century? Experience at University of Ljubljana from 2002 to 2022.

In this perspective analysis, we strive to answer the following question: how can we advance integrative biology research in the 21st century with lessons from animal science? At the University of Ljubljana, Biotechnical Faculty, Department of Animal Science, we share here our three lessons learned in the two decades from 2002 to 2022 that we believe could inform integrative biology, systems science, and animal science scholarship in other countries and geographies. Cultivating multiomics knowledge through a conceptual lens of integrative biology is crucial for life sciences research that can stand the test of diverse biological, clinical, and ecological contexts. Moreover, in an era of the current COVID-19 pandemic, animal nutrition and animal science, and the study of their interactions with human health (and vice versa) through integrative biology approaches hold enormous prospects and significance for systems medicine and ecosystem health.

Effects of Dietary Vitamin E, Vitamin C, Selenium and Their Combination on Carcass Characteristics, Oxidative Stability and Breast Meat Quality of Broiler Chickens Exposed to Cyclic Heat Stress.

The present study was conducted to investigate the effects of dietary supplementation with vitamin E, vitamin C, and Se, alone or in combination, on carcass characteristics, oxidative stability and meat quality parameters of breast meat from broilers exposed to cyclic heat stress (HS), and stored under different conditions. A total of 120 one-day-old male Ross 308 broilers were randomly assigned to six dietary treatments: NRC (minimal nutrition requirements), AVI (commercial nutritional recommendations for Ross 308 broilers), AVI + vitE (as AVI + 200 IU vitamin E/kg feed), AVI + vitC (as AVI + 250 mg vitamin C/kg feed), AVI + Se (as AVI + 0.2 mg Se/kg feed), and AVI + ECSe (as AVI + vitE + vitC + Se). From day 26 onwards, all birds were exposed to a high ambient temperature (31 °C) for 8 h per day. The results showed that dietary vitamin E alone or in combination with vitamin C and Se significantly increased the α-tocopherol content and decreased the malondialdehyde (MDA) content in breast meat. Although no obvious synergistic effects of the added antioxidants were observed, the addition of higher levels of vitamin E, vitamin C and Se to broiler diets had no adverse effects on carcass traits, oxidative stability and meat quality parameters when supplemented either alone or in combination.

Effect of Olive Leaves or Marigold Petal Extract on Oxidative Stress, Gut Fermentative Activity, and Mucosa Morphology in Broiler Chickens Fed a Diet Rich in n-3 Polyunsaturated Fats.

An experiment in broilers was conducted to investigate the effect of olive (Olea europea) leaves and marigold (Calendula officinalis) petal extract supplementation on oxidative stress, characteristics of intestinal contents, and on the morphology of the small intestine. Oxidative stress was induced by a n-3 polyunsaturated fatty acids rich diet. 1-day-old male broiler chickens, Ross 308, were housed in a deep litter system. After the first 21 days, animals were randomly divided into three groups of 16 animals in two replicates and fed, until slaughter on day 39, a diet that contained 7% linseed oil. Control diet (Cont) remained unsupplemented, while both experimental diets were supplemented with olive leaves (OliveEx) or marigold petal (MarigEx) extracts. Oxidative stress was evaluated in blood and liver by measuring markers of lipid peroxidation (malondialdehyde (MDA), isoprostanes), rate of DNA damage in lymphocytes and in blood (comet assay, 8-hydroxy-2'deoxyguanosine (8-OHdG)), and activity of antioxidant and liver enzymes in blood. In different parts of the intestine, levels of short chain fatty acids (SCFA), and viscosity of intestinal contents were measured, and the health of the gastrointestinal tract was assessed using histological measurements. OliveEx significantly (p<0.05) decreased the MDA and 8-OHdG concentration in plasma, and the level of ethanoic acid in small intestinal contents and total SCFA in caecum, indicating improved oxidative status and increased microbial activity in the intestine. MarigEx significantly (p<0.05) decreased the rate of lymphocyte DNA damage and the crypt depth in duodenum, indicating potentially beneficial effects on the immune system and the health of the small intestine. In conclusion, dietary OliveEx and MarigEx supplementation improved some markers of oxidative stress and intestinal health. However, positive effects could be more pronounced in more unfavorable environmental conditions or in cases of diseases, but further studies are needed.

Inflammation and its association with oxidative stress in dogs with heart failure.

BACKGROUND: Inflammation and oxidative stress can contribute to the development and progression of heart failure. This study aimed to investigate the association between inflammatory and oxidative stress markers in dogs with congestive heart failure (CHF). Associations between the disease severity marker N-terminal pro-B-type natriuretic peptide (NT-proBNP) and markers of inflammation and oxidative stress were also determined. RESULTS: Thirty-seven dogs with cardiovascular diseases (dilated cardiomyopathy, DCM (16 dogs), myxomatous mitral valve disease, MMVD (21 dogs)) and ten healthy dogs were included in this prospective study. The patients were further divided into groups with (26) and without CHF (11). We found a significantly higher serum concentration of C-reactive protein (P = 0.012), white blood cell (P = 0.001), neutrophil (P = 0.001) and monocyte counts (P = 0.001) in patients with CHF compared to control dogs. The concentration of tumor necrosis factor-alpha (TNF-α) was significantly higher in patients with CHF compared to patients without CHF (P = 0.030). No significant difference was found in most of the measured parameters between MMVD and DCM patients, except for glutathione peroxidase (GPX) and NT-proBNP. In patients with CHF, TNF-α correlated positively with malondialdehyde (P = 0.014, r = 0.474) and negatively with GPX (P = 0.026, r = - 0.453), and interleukin-6 correlated negatively with GPX (P = 0.046, r = - 0.412). NT-proBNP correlated positively with malondialdehyde (P = 0.011, r = 0.493). In patients without CHF none of the inflammatory and oxidative stress markers correlated significantly. Furthermore, in the group of all cardiac patients, GPX activity significantly negatively correlated with NT-proBNP (P = 0.050, r = - 0.339) and several markers of inflammation, including TNF-α (P = 0.010, r = - 0.436), interleukin-6 (P = 0.026, r = - 0.382), white blood cell (P = 0.032, r = - 0.369), neutrophil (P = 0.027, r = - 0.379) and monocyte counts (P = 0.024, r = - 0.386). CONCLUSION: Inflammatory and oxidative stress markers are linked in canine CHF patients, but not in patients without CHF. These results suggest complex cross communication between the two biological pathways in advanced stages of CHF.

Antioxidant capacity of lipid- and water-soluble antioxidants in dogs with subclinical myxomatous mitral valve degeneration anaesthetised with propofol or sevoflurane.

BACKGROUND: Antioxidants located in both the hydrophilic and lipophilic compartments of plasma act as a defence system against reactive oxygen species (ROS). Excessive production of ROS during anaesthesia affects the antioxidant capacity of plasma and may result in oxidative stress. The aim of this study was to evaluate the antioxidant capacity of lipid- (ACL) and water-soluble (ACW) antioxidants in client-owned dogs diagnosed with periodontal disease and early-stage myxomatous mitral valve degeneration (MMVD) and anaesthetised for a dental procedure with propofol and sevoflurane or with propofol only. RESULTS: Dogs with MMVD were anaesthetised with propofol and sevoflurane (MMVD/PS, n = 8) or with propofol only (MMVD/P, n = 10). Dogs with no evidence of MMVD (PS, n = 12) were anaesthetised with propofol and sevoflurane. Blood samples for determination of ACL and ACW were collected before and 5 min, 60 min and 6 h after induction to anaesthesia. In MMVD/PS dogs, ACL was significantly higher at all sampling times when compared to PS dogs. Compared to basal values, only anaesthesia maintained with propofol significantly increased ACL at 60 min in dogs with MMVD. In MMVD/P dogs, ACW increased after induction to anaesthesia and remained elevated up to 6 h after anaesthesia. Compared to basal values, anaesthesia maintained with sevoflurane significantly increased ACW only at 60 min in both dogs with and without MMVD. The only difference between propofol and propofol/sevoflurane anaesthesia in dogs with MMVD was significantly higher ACW at 60 min after induction to anaesthesia in the propofol group. CONCLUSIONS: Regarding antioxidant capacity, propofol could be a better choice than sevoflurane for anaesthesia of dogs with early-stage MMVD, although further studies are necessary to clarify the advantage of this antioxidant capacity.

Antioxidative Effects of Olive Polyphenols Compared to Vitamin E in Piglets Fed a Diet Rich in N-3 PUFA.

The aim of the current study was to assess the antioxidative effects of the dietary supplementation of olive leaf extract (OLE) in different concentrations compared to those of vitamin E in piglets under conditions of dietary n-3 PUFA-induced oxidative stress. Forty-eight castrated male piglets (10.6 ± 0.99 kg) were fed the following experimental diets: Cont- (low-fat diet, no supplement), Cont+ (high linseed oil diet, no supplement), Vit-E (as Cont+, 105 IU vitamin E/day), OLE-1 (as Cont+, 3.84 mg hydroxytyrosol equivalents (HEQs)/day), OLE-2 (as Cont+, 38.4 mg HEQ/day), and OLE-3 (as Cont+, 96 mg HEQ/day). After 21 days of feeding, the experimental diets, blood and urine samples were collected to assess the extent of the oxidative stress. Results indicated that diet OLE-1 lowered the activity of gamma-glutamyl transferase, protected DNA (measured as DNA tail %) and altered urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG). Dietary vitamin E lowered the levels of urinary F2-isoprostanes, as well as of plasma malondialdehyde and γ-tocopherol, but raised the plasmatic α-tocopherol and altered the level of urinary 8-OHdG. In conclusion, only minor positive effects of dietary OLE on the oxidative stress parameters were observed. Additionally, OLE did not show concentration dependence.

Effects of Olive Leaf and Marigold Extracts on the Utilization of Nutrients and on Bone Mineralization using Two Different Oil Sources in Broilers.

The aim of this study was to investigate the effects of olive leaf and marigold extracts on the apparent total tract digestibility (ATTD) of the principal nutrients and energy, as well as on mineral utilization (Ca, P, Mg, Mn, Fe, Cu and Zn) in relation to bone characteristics in broilers fed walnut- or linseed oil-supplemented diets. Thirty-six 12-day-old commercial broilers Ross 308 were reared in metabolic cages, assigned to one of the six dietary treatments (3 × 2 factorial design): three supplements (not supplemented, olive leaf extract, or marigold extract), and two oils (walnut or linseed oil). The results showed that the marigold extract reduced Zn and P balances and tended to lower the balance of ash and Mg, and the ATTD of Zn and Mg. Diets with linseed oil increased the ATTD of acid detergent fiber and reduced the ATTD of the organic residue and Cu. No differences in the bone characteristics of tibia were observed between treatments. These results indicated that the inclusion of marigold extract had a negative effect on the Zn and P balance, and that neither extract had any major effect on the digestion and utilization of energy and other investigated nutrients, or on bone mineralization, irrespective of the oil source included in the diet.

Supplementing entire male pig diet with hydrolysable tannins: Effect on carcass traits, meat quality and oxidative stability.

The purpose of the present study was to investigate the potential impact on carcass and meat quality of a sweet chestnut wood extract (SCWE)diet supplement for pigs, in particular on oxidative stability and fatty acid composition. Entire (non-castrated) male pigs (n=24) were assigned to treatment groups within litter and offered one of 4 finisher diets on an ad libitum basis: T0 (control), T1, T2 or T3, supplemented with 0, 1, 2 or 3% of commercially available SCWE, respectively. The highest SCWE supplementation reduced carcass fat deposition and water holding capacity of meat (higher thawing loss). In fresh meat, SCWE supplementation increased lipid (malondialdehyde) and protein oxidation (carbonyl groups in myofibril isolates). With regard to fat tissue, SCWE supplementation increased the proportion of polyunsaturated fatty acids.

Markers of oxidative stress in dogs with heart failure.

We tested the hypothesis that indirect measures of oxidative stress (vitamin E, glutathione peroxidase, and malondialdehyde) differ in dogs in heart failure resulting from either myxomatous mitral valve disease or dilated cardiomyopathy. Dogs were classified according to the International Small Animal Cardiac Health Council (ISACHC) classification. Additionally, the effect of cardiac therapy on oxidative stress parameters and N-terminal pro-B-type natriuretic peptide (NT-proBNP) in advanced stages of congestive heart failure was investigated. There were no significant differences in oxidative stress parameters between healthy dogs and the individual groups of cardiac patients. Significantly lower malondialdehyde (MDA) was observed in the ISACHC II group in comparison to ISACHC groups III and I. A significant positive correlation in treated patients was observed between NT-proBNP and MDA, NT-proBNP and vitamin E, as well as between MDA and vitamin E (and lipid-standardized vitamin E). No significant differences in any of the measured parameters were found between treated and non-treated cardiac patients. Our results suggest an association between MDA (the extent of lipid peroxidation) and NT-proBNP, vitamin E and NT-proBNP, as well as between MDA and vitamin E in treated canine patients. Plasma vitamin E concentration was maintained in all stages of cardiovascular disease in these canine patients.

The comparison of black currant juice and vitamin E for the prevention of oxidative stress.

Black currant is known as a fruit with a very strong in vitro antioxidative capacity, but its in vivo antioxidant efficacy has not yet been characterized. The aim of the experiment was to determine the potency of black currant juice in comparison to vitamin E, for decreasing oxidative stress. Oxidative stress was induced by high intake of polyunsaturated fatty acids (PUFAs) in pigs as a model for humans. Twenty-four growing pigs were divided into four groups. All groups received isocaloric daily rations composed of an equal amount of basal diet that was supplemented with starch (CONT), linseed oil (OIL), linseed oil and black currant juice (OIL+BCJ), or linseed oil and vitamin E (OIL+VIT E). The experiment confirmed that the high proportion of PUFAs in the OIL group increased oxidative stress. In comparison with the OIL group, vitamin E supplementation significantly lowered plasma malondiadehyde (MDA) and the 24-hour urine MDA excretion rate, and reduced the degree of DNA damage in leukocytes to the level of the CONT group. The black currant juice intake failed to significantly decrease plasma MDA and 24-hour urine MDA excretion rate, but did reduce the degree of DNA damage in leukocytes to the level of the CONT group, as well as increase plasma beta+gamma-tocopherol concentrations. Although black currant juice did not reduce the formation of MDA, it efficiently prevented DNA damage induced by the high intake of PUFAs. It could be concluded that under these experimental conditions vitamin E was more efficient as an antioxidant that black currant juice.

Efficiency of apples, strawberries, and tomatoes for reduction of oxidative stress in pigs as a model for humans.

OBJECTIVE: The present study investigated the potency of apples, strawberries, and tomatoes in decreasing oxidative stress in pigs as a model for humans. METHODS: Forty-eight growing pigs were individually penned in metabolic cages and divided into six groups. All groups received isocaloric daily rations composed of a basal diet supplemented with starch, linseed oil, linseed oil and apples, linseed oil and strawberries, linseed oil and tomatoes, or linseed oil, apples, strawberries and tomatoes. Oxidative stress was evaluated at the beginning and at the end of the 22-d experimental period by measuring the degree of DNA damage in mononuclear blood cells, the concentration of malondialdehyde (MDA) in plasma, the MDA excretion rate, the concentration of tocopherols in plasma, plasma total antioxidant status, and erythrocyte glutathione peroxidase concentration. RESULTS: The results confirmed that the linseed oil diet significantly increased MDA formation in the body and DNA damage to mononuclear blood cells in comparison with the starch diet. Although the MDA concentration in plasma was significantly decreased in all fruit groups, urine MDA excretion rate was decreased only in the linseed oil/apple and linseed oil/apple/strawberry/tomato groups. Supplementation with fruit significantly decreased DNA damage, was more pronounced in the linseed oil/apple and linseed oil/apple/strawberry/tomato groups. Significantly lower glutathione peroxidase concentrations were observed only in the linseed oil/strawberry group. CONCLUSIONS: Our findings support the hypothesis that supplementation with apples, strawberries, or tomatoes effectively decreases oxidative stress by decreasing MDA formation in the body and by protecting mononuclear blood cells against increased DNA damage. This effect was particularly pronounced in the group supplemented with a fruit mixture; among the single fruit supplements, the most beneficial effect was obtained with apples.