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This study was conducted to determine whether the plasma and brain concentrations of AFB1 are affected by the modulation of P-gp and BCRP using zosuquidar (ZQR) and prazosin (PRZ), respectively. In this study, a total of 40 healthy adult male BALB/c mice (32±3.7 g) were used. The animals were randomly divided into 5 groups, with 8 animals per group. Group 1 was used for method validation. Group 2 (AF) received intraperitoneal AFB1 at a dose of 20 mg/kg of body weight. Groups 3 (AF+PRZ), 4 (AF+ZQR), and 5 (AF+PRZ+ZQR) received 20 mg/kg of AFB1 intraperitoneally 30 min after the intraperitoneal administration of prazosin (0.3 mg/kg), zosuquidar (25 mg/kg), and prazosin+zosuquidar (0.3 mg/kg prazosin + 25 mg/kg zosuquidar), respectively. Six hours after the administration of AFB1, blood and brain samples were collected from the animals in Groups 2 to 5. AFB1 concentrations were determined using an HPLC system with fluorescence detection. Individual and simultaneous administration of prazosin and zosuquidar significantly reduced the brain concentrations of AFB1 in comparison to a single administration of AFB1 (P

1. This study was conducted using male broiler chickens to determine the effects of ascorbic acid, aspirin, ascorbic acid+aspirin, vitamin E+selenium and ascorbic acid+aspirin+vitamin E+selenium supplementations on haematological parameters and serum superoxide dismutase concentration. 2. One hundred and twenty day-old male Hubbunt broiler chicks were randomly divided into 6 experimental groups of 20 chicks each and placed in different pens. Groups 2, 3, 4, 5 and 6 were given a diet supplemented with ascorbic acid, aspirin (in water), ascorbic acid+aspirin, vitamin E+selenium and ascorbic acid+aspirin+vitamin E+selenium, respectively for 45 d while group 1 was given a commercial broiler diet. 3. There was no significant effect of ascorbic acid, aspirin, ascorbic acid+aspirin, vitamin E+selenium supplementations on any of the haematological parameters (red blood cell, haemoglobin, haematocrit, mean corpuscular volume, mean corpuscular haemoglobin concentration, mean corpuscular haemoglobin) in broilers but ascorbic acid+aspirin+vitamin E+selenium supplementation significantly decreased the white blood cell counts. 4. In addition to this, ascorbic acid, aspirin, ascorbic acid+aspirin and ascorbic acid+aspirin+vitamin E+selenium supplementations had no significant effect on the serum superoxide dismutase level, but vitamin E+selenium supplementation increased the serum superoxide dismutase level. [ABSTRACT FROM AUTHOR]

This study aimed to determine the effect of administration of oral vitamins A and E at different doses on plasma and brain concentrations of ivermectin in mice. The study was carried out on 174 Swiss Albino male mice aged 8-10 weeks. After leaving six mice for method validation, the remaining mice were randomly divided into seven groups with equal numbers of animals. Mice received ivermectin (0.2 mg/kg, subcutaneous) alone and in combination with low (vitamin A: 4000 IU/kg; vitamin E: 35 mg/kg) and high (vitamin A: 30 000 IU/kg; vitamin E: 500 mg/kg) oral doses of vitamins A and E. The plasma and brain concentrations of ivermectin were measured using high-performance liquid chromatography-fluorescence detector. We determined that high doses of vitamins A and E and their combinations increased the passing ratio of ivermectin into the brain significantly. The high-dose vitamin E and the combination of high-concentration vitamins E and A significantly increased the plasma concentration of ivermectin ( P  < 0.05). The high-dose vitamins E and A and their high-dose combination increased the brain concentration of ivermectin by 3, 2, and 2.7 times, respectively. This research is the first in vivo study to determine the interaction between P-gp substrates and vitamins E and A., Competing Interests: The authors declare that they have no conflict of interest.

The combination of oxfendazole and oxyclozanide is used to provide activity against fluke and gastrointestinal nematodes. This study aimed to determine both the pharmacokinetics of oxfendazole (7.5 mg/kg) and oxyclozanide (15 mg/kg) tablet formulation administered orally to sheep and whether there is a pharmacokinetic interaction between these two drugs. The study was conducted in a three-period, crossover pharmacokinetic design and on six healthy Awassi sheep 1-3 years of age. The plasma concentrations of oxfendazole and its metabolites (fenbendazole and fenbendazole sulphone) and oxyclozanide were determined by high-performance liquid chromatography using an ultraviolet detector. Compounds recovered in plasma when oxfendazole was administered alone or combined with oxyclozanide were oxfendazole, fenbendazole sulphone, and fenbendazole, respectively. When oxfendazole was administered alone and co-administered with oxyclozanide, the AUC FBZ /AUC OFZ was 0.26 and 0.23, respectively, and the AUC FBZSO2 /AUC OFZ was 0.35 and 0.32, respectively. The volume of distribution (Vz/F) of oxfendazole was large in both groups. Oxyclozanide did not change the plasma disposition of oxfendazole. When the oxyclozanide tablet formulation was administered alone, the elimination half-life (21.35 h) and the Vz/F (940.17 ml/kg) were long and large, respectively. The area under the curve (AUC) and the maximum plasma concentration of oxyclozanide were significantly larger and higher, respectively, in the oxyclozanide plus oxfendazole group (1146.61 h × μg/ml and 29.80 μg/ml) compared with the oxyclozanide group (491.44 h × μg/ml and 14.24 μg/ml) while a significant decrease in apparent Vz/F (940.17 vs 379.14 ml/kg) and total clearance (30.52 vs 13.08 ml/h/kg) was detected. In conclusion, co-administration with oxfendazole causing an increase in the plasma profile of oxyclozanide may increase the antiparasitic activity of oxyclozanide., (© 2022 John Wiley & Sons Ltd.)

This study was aimed to determine the pharmacokinetics of antisecretory-acting racecadotril, used in the treatment of diarrhea in humans and dogs, following oral administration in both neonatal calves with healthy and neonatal calves with infectious diarrhea. The study was carried out on a total of 24 Holstein calves (2-20 days), of which 6 were healthy and 18 were infectious diarrhea. Calves with infectious diarrhea were divided into 3 groups according to the infectious agent (Escherichia coli, Cryptosporidium parvum, and rotavirus/coronavirus). Racecadotril was administered orally at 2.5 mg/kg dose to calves. The plasma concentrations of racecadotril and its main active metabolite (thiorphan) were determined using HPLC-UV. The pharmacokinetic parameters were analyzed using the non-compartmental method. In healthy calves, the t 1/2ʎz , C max , T max, and AUC 0-12 of racecadotril were determined 4.70 h, 377 ng/ml, 0.75 h, and 1674 h × ng/ml, respectively. In the plasma of calves with infectious diarrhea, racecadotril and thiorphan were only detected at the sampling time from 0.25 to 1.5 h. As in calves with infectious diarrhea, thiorphan in plasma was only detected in healthy calves from 0.25 to 1.5 h. Racecadotril showed a large distribution volume, rapid elimination, and low metabolism to thiorphan in healthy calves., (© 2022 John Wiley & Sons Ltd.)

This study was conducted to investigate the effects of matrix metalloproteinase (MMP) inhibitors dexamethasone and minocycline administrations -both single and in combination with N-acetylcysteine (NAC) and vitamin E-on the tissue distribution and lethal dose (LD) 50 of aflatoxin (AF)B 1 in rats. We performed this study on male Wistar rats (8-10 weeks) in two phases. In the first phase, rats were administered dexamethasone (5 and 20 mg/kg) and minocycline (45 and 90 mg/kg), both as single treatments and in combination with NAC (200 mg/kg) and vitamin E (600 mg/kg); these treatments followed AFB 1 administration (2 mg/kg). In the second phase, the therapeutic effect value (TEV) was calculated to determine the treatment effect on the LD 50 level of AFB 1 . The tissue affinity of AFB1 from high to low was liver, kidney, intestine, brain, heart, spleen, lung, testis, and vitreous humor, respectively. Dexamethasone at the 20 mg/kg dose significantly reduced AFB 1 concentrations in the plasma and the other tissues, except for the vitreous humor. The effects of minocycline on the plasma and tissue concentrations of AFB 1 varied by dose and tissue. The combinations of dexamethasone or minocycline with NAC and vitamin E increased the AFB 1 concentrations in the plasma and all tissues, except for vitreous humor and liver. In male rats, the LD 50 value of AFB 1 was 11.86 mg/kg. The TEV of dexamethasone (20 mg/kg) was calculated to be 1.5. Dexamethasone can be administered in repeated doses at ≥20 mg/kg to increase survival in AFB 1 poisoning., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

To determine the effects of alpha lipoic acid (ALA) and vitamin E (Vit E) on mitochondrial dysfunction caused by statins. A total of 38 Wistar Albino rats were used in this study. The control group received dimethyl sulfoxide. The atorvastatin (A) group received atorvastatin (10 mg/kg). The A + ALA group received atorvastatin (10 mg/kg) and ALA (100 mg/kg). The A + Vit E group was administered atorvastatin (10 mg/kg) and Vit E (100 mg/kg). The A + ALA + Vit E group was administered atorvastatin (10 mg/kg), ALA (100 mg/kg) and Vit E (100 mg/kg). All applications were administered simultaneously by gavage for 20 days. ATP level and complex I activity were measured from liver, muscle, heart, kidney and brain. Atorvastatin significantly decreased the ATP levels in heart and kidney, while a slight decrease was seen in liver, muscle and brain. Atorvastatin caused an insignificant decrease in the complex I activity in all tissues examined. ALA administration significantly improved the ATP levels in the liver, heart and kidney, while Vit E improved the ATP levels in all tissues except the muscle compared to Atorvastatin group. Single administration of both ALA and vit E ameliorated complex I activity in the muscle, heart, kidney and brain. The combination of ALA and Vit E significantly improved the ATP levels in the liver, heart, kidney and brain and also provided significant improvements the complex I activity in all tissues. The undesirable effects of Atorvastatin on mitochondrial functions in this study ameliorated by using ALA and/or Vit E alone and in combination., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. and Mitochondria Research Society. All rights reserved.)

The purpose of this study was to determine the pharmacokinetic interaction between ivermectin (0.4 mg/kg) and praziquantel (10 mg/kg) administered either alone or co-administered to dogs after oral treatment. Twelve healthy cross-bred dogs (weighing 18-21 kg, aged 1-3 years) were allocated randomly into two groups of six dogs (four females, two males) each. In first group, the tablet forms of praziquantel and ivermectin were administered using a crossover design with a 15-day washout period, respectively. Second group received tablet form of ivermectin plus praziquantel. The plasma concentrations of ivermectin and praziquantel were determined by high-performance liquid chromatography using a fluorescence and ultraviolet detector, respectively. The pharmacokinetic parameters of ivermectin following oral alone-administration were as follows: elimination half-life (t 1/2λz ) 110 ± 11.06 hr, area under the plasma concentration-time curve (AUC 0-∞ ) 7,805 ± 1,768 hr . ng/ml, maximum concentration (C max ) 137 ± 48.09 ng/ml, and time to reach C max (T max ) 14.0 ± 4.90 hr. The pharmacokinetic parameters of praziquantel following oral alone-administration were as follows: t 1/2λz 7.39 ± 3.86 hr, AUC 0-∞ 4,301 ± 1,253 hr . ng/ml, C max 897 ± 245 ng/ml, and T max 5.33 ± 0.82 hr. The pharmacokinetics of ivermectin and praziquantel were not changed, except T max of praziquantel in the combined group. In conclusion, the combined formulation of ivermectin and praziquantel can be preferred in the treatment and prevention of diseases caused by susceptible parasites in dogs because no pharmacokinetic interaction was determined between them., (© 2019 John Wiley & Sons Ltd.)

This study investigated the pharmacokinetics of pentoxifylline (PTX) and its 5-hydroxyhexyl metabolite (M-I) after single-dose intravenous (IV) administration (10 mg/kg) of PTX in six healthy cattle. The safety of PTX was evaluated by clinical observation and biochemical analysis. Plasma concentrations of PTX and M-I were simultaneously determined by reverse-phase high performance liquid chromatography. Pharmacokinetic parameters were calculated using non-compartmental methods. Salivation and discomfort were observed for 2 h following the drug administration. Serum direct bilirubin, total bilirubin, and phosphorus levels at 24 h following the drug administration were significantly different from the control values (0 h) (P < 0.05). Pharmacokinetic variables of PTX were characterized by a short terminal elimination half-life (1.05 ± 0.19 h), a large volume of distribution (6.30 ± 1.76 L/kg), and high total body clearance (5.31 ± 1.27 L/h/kg). The mean ratio between the area under the concentration-time curves of M-I and PTX was 1.34. These results indicate that single-dose administration of PTX at 10 mg/kg IV in cattle resulted in therapeutic concentrations similar to those observed in humans and horse. However, further studies are necessary to determine the safety and pharmacokinetics following repeated administrations of PTX.

This study was conducted to determine the passage ratio of amoxicillin into milk and its pharmacokinetics in milk and plasma after intramuscular administration. Five healthy dairy cows (Holstein, weighing 450-500 kg, aged 2-4 years) were used in this study. They received single intramuscular amoxicillin at a dose of 14 mg/kg body weight. Blood and milk samples were collected prior to drug administration (0); after 15, 30, 45, 60, and 90 min; and 2, 3, 4, 6, 8, 10, and 12 hr after administration. The plasma and milk concentrations of amoxicillin were determined using high-performance liquid chromatography with ultraviolet detection. The passage ratio of amoxicillin into milk and plasma was determined using both AUC-based calculation and milk and plasma concentrations at sampling times; it was calculated 0.46 and 0.52, respectively. The terminal half-life and mean residence time of amoxicillin were 6.05 and 8.60 hr in plasma and 2.62 and 5.35 hr in milk, respectively. The C max2 levels of amoxicillin in plasma and milk were measured as 1,096 and 457 ng/ml, respectively. It was observed that amoxicillin exhibited a secondary peak in plasma and milk. This study was the first to report on the passage ratio of amoxicillin into milk in lactating cows., (© 2018 John Wiley & Sons Ltd.)

The purpose of this study was to investigate the effect of breed on the pharmacokinetics and metabolism of caffeine (CF) and the hepatic metabolic capacity in sheep. CF was administered as a single intravenous dose of 5 mg/kg b.w. in Morkaraman (MK), Akkaraman (AK) and Anatolia Merino (AM) sheep breeds. The plasma levels of CF and its primary metabolites, theobromine (TB), paraxanthine (PX) and theophylline (TP), were measured using high-performance liquid chromatography. Pharmacokinetic parameters of CF and its metabolites were calculated. Plasma TB+PX+TP/CF metabolic ratio was determined as an alternative to CF clearance for the determination of hepatic metabolic capacity. In the three breeds, all kinetic parameters of CF differed significantly (P<0.05) except for volume of distribution. Elimination of CF was slow in the MK (Cl(T); 0.03 ± 0.01 l hr/kg, t(1/2λz); 15.74 ± 7.35 hr) and AM (Cl(T); 0.05 ± 0.02 l hr/kg, t(1/2λz); 9.68 ± 5.21 hr) breeds when compared with the AK breed (Cl(T); 0.08 ± 0.01 l hr/kg, t(1/2λz); 6.84 ± 0.79 hr). There was significant correlation (r(2)=0.904, P<0.01) between CF clearance and the plasma TB+PX+TP/CF ratio calculated at 7 hr after CF administration. The plasma TB+PX+TP/CF ratios were statistically different (P<0.05) among the breeds (MK, 0.155 ± 0.062; AK, 0.468 ± 0.107; AM, 0.254 ± 0.099). These results suggest that the pattern of drug biotransformation should be consistently tested for all breeds within species. Further studies are needed to determine the biochemical and molecular events underlying such an effect.

The aim of this study was to determine the effects of drugs used in the treatment of endotoxaemia on disseminated intravascular coagulation, cytokine levels and adenosine deaminase activities in endotoxaemic rats. Rats were divided into seven groups. Lipopolysaccharide (LPS) was injected into all groups, including the positive control group. The other six groups received the following drugs: enrofloxacin (ENR), flunixin meglumine (FM), low-dose dexamethasone (DEX), high-dose DEX, ENR + FM + low-dose DEX, and ENR + FM + high-dose DEX. After the treatments, serum and plasma samples were collected at 0, 1, 2, 4, 6, 8, 12, 24 and 48 hours (h). A coagulometer was used to determine the levels of coagulation values, while ELISA was used to assay serum cytokines and adenosine deaminase (ADA). Low-dose DEX alone and combined treatments depressed the levels of cytokines and ADA (from 371 to 70 IU/L at 6 h) significantly and inhibited the decrease of coagulation values (antithrombin from 67 to 140% at 6 h, fibrinogen from 54 to 252 mg/dL at 6 h). In summary, FM + high-dose DEX may be the preferred treatment of endotoxaemia because of its highest effectiveness. FM plus high-dose DEX may be a new therapy for endotoxaemic domestic animals.

The aim of this study was to determine the effects of enrofloxacin (ENR), flunixin meglumine (FM) and dexamethasone (DEX) on antioxidant status and organ damage markers in experimentally-induced endotoxemia. Rats were divided into three groups. To induce endotoxemia, lipopolysaccharide (LPS) was injected into all groups, including the positive control. The two other groups received the following drugs (simultaneously with LPS): ENR + FM + low-dose DEX and ENR + FM + high-dose DEX. After the treatments, blood samples were collected at 0, 1, 2, 4, 6, 8, 12, 24 and 48 h. Oxidative stress parameters were determined by ELISA, while serum organ damage markers were measured by autoanalyser. LSP increased (p < 0.05) malondialdehyde, 13,14-dihydro-15-keto-prostaglandin F(2 alpha) and nitric oxide, while LPS reduced vitamin C. These changes were especially inhibited (p < 0.05) by ENR + FM + high-dose DEX. LPS increased organ damages markers. Cardiac and hepatic damage was not completely inhibited by any treatment, whereas renal damage was inhibited by two treatments. This study suggested that ENR + FM + high-dose DEX is most effective in the LPS-caused oxidative stress and organ damages.

Pharmacokinetics and bioavailability of enrofloxacin were determined after single intravenous (IV) and intramuscular (IM) administrations of 5 mg/kg body weight (BW) to 5 healthy adult Angora goats. Plasma enrofloxacin concentrations were measured by high performance liquid chromatography. Pharmacokinetics were best described by a 2-compartment open model. The elimination half-life and volume of distribution after IV and IM administrations were similar (t1/2beta, 4.0 to 4.7 h and Vd(ss),1.2 to 1.5 L/kg, respectively). Enrofloxacin was rapidly (t1/2a, 0.25 h) and almost completely absorbed (F, 90%) after IM administration. Mean plasma concentrations of enrofloxacin at 24 h after IV and IM administration (0.07 and 0.09 microg/mL, respectively) were higher than the minimal inhibitory concentration (MIC) values for most pathogens. In conclusion, once-daily IV and IM administration of enrofloxacin (5 mg/kg BW) in Angora goats may be useful in treatment of infectious diseases caused by sensitive pathogens.