Ayse Er

Effects of drugs used in endotoxic shock on oxidative stress and organ damage markers.

Abstract 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 F2α 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.

EFFECTS OF TYLOSIN ON SERUM CYTOKINE LEVELS IN HEALTHY AND LIPOPOLYSACCHARIDE-TREATED MICE

The effects of different doses of tylosin on serum cytokine concentrations were investigated in healthy and lipopolysaccharide-treated mice. The mice were divided into seven groups. Lipopolysaccharide (LPS) was injected into the positive control group. The other six groups received three different tylosin doses concurrently without or with LPS: 10 mg/kg, 100 mg/kg, 500 mg/kg, 10 mg/kg + LPS, 100 mg/kg + LPS and 500 mg/kg + LPS. After treatment, serum samples were collected at 0, 1, 2, 3, 6, 12 and 24 hours. Serum tumour necrosis factor alpha (TNFalpha), interleukin 1beta (IL1beta) and IL10 levels were determined by enzyme-linked immunosorbent assay (ELISA). Tylosin doses of 10 and 100 mg/kg induced no cytokine production in the healthy mice. Tylosin at 500 mg/kg had no effect on TNFalpha or IL1beta production, but it induced IL10 production in healthy mice. All doses of tylosin reduced the elevated TNFalpha and IL1beta in LPS-treated mice but increased their IL10 levels. In conclusion, these data suggest that tylosin has an immunomodulatory effect at the dose recommended for use against infection.

Effects of enrofloxacin, flunixin meglumine and dexamethasone on disseminated intravascular coagulation, cytokine levels and adenosine deaminase activity in endotoxaemia in rats+

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.

Assessment of the cardiotoxicity of tulathromycin in rabbits.

The aim of this study was to determine the cardiotoxic potency of tulathromycin. Tulathromycin (10 mg/kg, SC) was administered to ten adult male rabbits, and blood samples were obtained before and after drug administration (0 and 6 hours). Serum cardiac damage markers (troponin I, creatine kinase-MB, myoglobin, lactate dehydrogenase, aspartate aminotransferase), routine serum biochemical values (alkaline phosphatase, alanine aminotransferase, gamma-glutamyltransferase, creatinine, blood urea nitrogen, cholesterol, triglyceride, high-density lipoprotein, amylase, total protein, albumin, glucose, calcium, ionised calcium, sodium, potassium), white blood cell (WBC) and red blood cell (RBC) counts, arterial blood gas parameters (pH, partial carbon dioxide pressure, partial oxygen pressure, actual bicarbonate, standard bicarbonate, total carbon dioxide, base excess in vivo, base excess in vitro, oxygen saturation, packed cell volume, haemoglobin) and serum oxidative status (malondialdehyde, nitric oxide, superoxide dismutase, retinol, β-carotene) were measured. Increased levels of troponin I, creatine kinase-MB and creatinine, and decreased WBC counts, ionised calcium and potassium levels were observed after drug administration. Tulathromycin treatment may cause cardiotoxicity, but its effects may be less dramatic than those of other macrolide antibiotics frequently used in veterinary medicine.

Effects of different doses of dexamethasone plus flunixin meglumine on survival rate in lethal endotoxemia.

Effects of different doses of dexamethasone plus flunixinmeglumine on survival rate were investigated in lethal endotoxemia. Atotal of 60 Balb/C female mice were divided into 4 equal groups. Lethalendotoxemia (80-100%) was induced by lipopolysaccharide injection(Group 1, 1 mg, intraperinoneally). At 4 hours after the lipopoly-saccharide injection; low-dose dexamethasone (0.6 mg/kg, SID, 5days, intramuscularly) + flunixin meglumine (2 mg/kg, SID, 5 days,subcutaneously), normal-dose dexamethasone (2 mg/kg, SID, 5 days,intramuscularly) + flunixin meglumine (2 mg/kg, SID, 5 days,subcutaneously) and high-dose dexamethasone (10 mg/kg, SID, 5days, intramuscularly) + flunixin meglumine (2 mg/kg, SID, 5 days,subcutaneously) were injected to Group 2, 3 and 4, respectively. Afterthe injections, survival was monitored at 7 days and 13.3%, 13.3%,33.3% and 73.3% survival rates were observed in Groups 1, 2, 3 and 4,respectively. As results, high-dose dexamethasone plus flunixinmeglumine may be the treatment of choice for endotoxaemia inanimals.Key words: lethal endotoxaemia, dexamethasone, flunixin,survival rate

Effects of tylosin, tilmicosin and tulathromycin on inflammatory mediators in bronchoalveolar lavage fluid of lipopolysaccharide-induced lung injury

The aim of this study was to determine the anti-inflammatory effects of macrolides through kinetic parameters in bronchoalveolar lavage fluid (BALF) of lipopolysaccharide-induced lung injury. Rats were divided into four groups: lipopolysaccharide (LPS), LPS + tylosin, LPS + tilmicosin and LPS + tulathromycin. BALF samples were collected at sampling times. TNF, IL-1β, IL-6, IL-10 and 13,14-dihydro-15-keto-prostaglandin F2α (PGM) and C-reactive protein (CRP) were analysed. Area under the curve (AUC) and maximum plasma concentration (Cmax) values of inflammatory mediators were determined by a pharmacokinetic computer programme. When inflammatory mediator concentrations were compared between the LPS group and other groups for each sampling time, the three macrolides had no pronounced depressor effect on cytokine levels, but they depressed PGM and CRP levels. In addition, tylosin and tilmicosin decreased the AUC0-24 level of TNF, while tilmicosin decreased the AUC0-24 level of IL-10. Tylosin and tulathromycin decreased the AUC0-24 of PGM, and all three macrolides decreased the AUC0-24 of CRP. Especially tylosin and tulathromycin may have more expressed anti-inflammatory effects than tilmicosin, via depressing the production of inflammatory mediators in the lung. The AUC may be used for determining the effects of drugs on inflammation. In this study, the antiinflammatory effects of these antibiotics were evaluated with kinetic parameters as a new and different approach.

The effects of florfenicol on the values of serum tumor necrosis factor-α and other biochemical markers in lipopolysaccharide-induced endotoxemia in brown trout.

The aim of the present study was to determine the effects of florfenicol on the expected changes in sTNF-α, damage markers of the liver and kidney, and the lipid metabolism parameters in endotoxemic brown trout. Ninety-six brown trout were included in this study. After six of the fish were reserved as the control group, the remaining 90 fish were divided equally into 3 groups as follows: LPS (2 mg/kg, IP), LPS (2 mg/kg, IP) + florfenicol (40 mg/kg, IM), and florfenicol (40 mg/kg, IM). Blood samples were obtained from the tail of the fish at 1.5, 3, 6, 10, and 24 hours. The levels of sTNF-α were determined by ELISA and biochemical markers were evaluated with an autoanalyzer. A significant increase was observed in the values of sTNF-α in the LPS and LPS + florfenicol groups (P < 0.05). Significant increases were found in the kidney and liver damage determinants in the LPS and LPS + florfenicol groups (P < 0.05). Irregular changes in the lipid metabolism parameters were observed in all the subgroups. In conclusion, florfenicol does not affect the increases of sTNF-α caused by LPS and does not prevent liver or kidney damage; at least, it can be said that florfenicol does not have any evident positive effects on the acute endotoxemia of fish.

Cardiac Safety of Diclofenac at a Single Dose in Ram

Nonsteroidal anti-inflammatory drugs are frequently prescribed drug group in human and veterinary medicine. However, diclofenac, a traditional nonsteroidal anti-inflammatory drug, related to cardiotoxicity is reported, and blood cardiac damage markers may increase within the first hours after damage. The aim of the current research was to determine the effect of diclofenac on the blood cardiac damage markers. Single dose of diclofenac (2.5 mg/kg, IM) was injected to 6 rams. Blood samples were collected in before (0 hour, control) and 6 hours after injection. Specific (troponin I, and creatine kinase-MB) and nonspecific (lactate dehydrogenase, aspartate aminotransferase) blood cardiac damage marker concentrations, routine biochemical (hepatic damage, renal damage, lipid metabolism, glucose, and phosphorus) parameters, and hemogram values were measured. Diclofenac increased (P < 0.05) specific (troponin I) and nonspecific cardiac (lactate dehydrogenase, aspartate aminotransferase), hepatic (aspartate aminotransferase, alkaline phosphatase, and alanine aminotransferase), and muscular (creatine kinase) damage markers and high density lipoprotein level, while it decreased (P < 0.05) low density lipoprotein level. Moreover, diclofenac decreased (P < 0.05) white blood cell counts and increased (P < 0.05) red blood cell counts. In conclusion, it may be stated that diclofenac shows slight cardiotoxicity, whereas it may show potent hepatic and muscular damage effects at an intramuscularly single dose in sheep. Thereby, repeated injections of diclofenac may be more harmful in sheep.

Plasma and tissue disposition of danofloxacin in brown trout (Salmo trutta fario) after intravenous and intramuscular administrations

ABSTRACT Plasma and muscle pharmacokinetics of danofloxacin were investigated after 10 mg/kg intravenous (IV, caudal vein) and intramuscular (IM, right epaxial muscles) administrations in 168 healthy brown trout (Salmo trutta fario) at 10°C–13°C. High-performance liquid chromatography was used to determine its plasma and muscle concentrations. Pharmacokinetic parameters were analysed with a non-compartmental model. After IV administration, elimination half-life (t1/2ʎz), area under the concentration–time curve (AUC0–∞), mean residence time (MRT0–∞), volume of distribution at steady state, total body clearance in plasma and AUCMuscle/AUCPlasma ratio were 22.22 h, 140.66 h*µg/mL, 23.15 h, 2.28 L/kg, 0.07 L/h/kg and 3.79, respectively. After IM administration, t1/2ʎz, AUC0–∞, MRT0–∞, peak concentration (Cmax), time to reach Cmax, bioavailability in plasma and AUCMuscle/AUCPlasma ratio were 28.28 h, 84.39 h*µg/mL, 37.31 h, 4.79 µg/mL, 1 h, 59.99% and 8.46, respectively. Danofloxacin exhibited long t1/2ʎz and good bioavailability after IM administration. Therefore, 10 mg/kg IM administration of danofloxacin in brown trout can provide AUC0–24/MIC of > 125 and Cmax/MIC of > 10 to treat diseases caused by susceptible bacteria with ≤ 0.336 µg/mL MIC.

Investigation of the Effect of Tarantula cubensis Extract on Acute Phase Response

Background: Tarantula cubensis alcoholic extract is used to accelerate wound healing and to relieve edema in many animal species. In addition, it may be useful for many infectious diseases. Considering to these effects, it is believe that these effects may be on immune system. Cytokines (tumor necrosis factor alpha, interleukin-1 beta, interleukin-6, interleukin-10 and interferon gamma) secreted by immune cells and acute phase proteins (haptoglobin, alpha 1 acid glycoprotein, serum amyloid A) secreted by liver play role in acute phase response. The aim of the present study was to determine the effect of Tarantula cubensis alcoholic extract on cytokine and acute phase protein levels in sheep. Materials, Methods & Results: Tarantula cubensis alcoholic extract (6 mL/sheep, subcutaneously, single dose) was administered to 6 healthy sheep. Blood samples were obtained before (0 h) and after treatments at 2, 4, 8, 12, 24 and 48 h. Then, blood samples were centrifuged to obtain serum samples. Acute phase cytokines such as serum tumor necrosis factor alpha, interleukin-1 beta, interleukin-6, interleukin-10, interferon gamma and acute phase proteins such as haptoglobin, alpha 1 acid glycoprotein and serum amyloid-A concentrations were determined with commercially available kits on ELISA reader. Administration of Tarantula cubensis alcoholic extract caused fluctuations in tumor necrosis factor alpha, interleukin-1 beta, interleukin-6, interleukin-10, interferon gamma levels in sheep. In addition, levels of haptoglobin, alpha 1 acid glycoprotein, serum amyloid A showed fluctuations. But, these fluctuations in acute phase cytokines and acute phase proteins were not statistically significant (P > 0.05). Discussion: Tarantula cubensis alcoholic extract, homeopathic medicine, is used trauma, retentio secundinarium, tendinitis, bluetongue, foot and mouth, metritis and arthritis in many animal species including sheep. Cytokines, secreted against various stimulus including infectious diseases, play role in wound healing and in the regulation of the immune system. In current study, administration of Tarantula cubensis alcoholic extract lead to fluctuations in tumor necrosis factor alpha, interleukin-1 beta, interleukin-6, interleukin-10 and interferon gamma levels, but these changes were not statistically significant (P > 0.05). Non-statistical fluctuations in cytokines result from inadequate immunological response of sheep against to Tarantula cubensis alcoholic extract. Also, use of molecular analysis techniques may be changed these results. Acute phase proteins are significantly secreted from the liver during the acute phase response. In current study, administration of Tarantula cubensis alcoholic extract in sheep caused non-statistifical fluctuations on haptoglobin, alpha 1 acid glycoprotein and serum amyloid A levels (P > 0.05). Tumor necrosis factor alpha and interleukin-1 beta stimulate synthesis of interleukin-6. Interleukin-6 provides synthesis of acute phase proteins in liver. Non-statistical fluctuations in acute phase proteins result from inadequate stimulus of IL-6. In conclusion, it may be stated that administration of Tarantula cubensis alcoholic extract has no distinctive effect on the acute phase response. However, when Tarantula cubensis alcoholic extract is administered repeated times or other acute phase parameters are evaluated, different results may be observed.