Plasma Concentrations Of Tumor Necrosis Factor-alpha Research Articles

Effects of dietary protein content and crystalline amino acid supplementation patterns on growth performance, intestinal histomorphology, and immune response in weaned pigs raised under different sanitary conditions.

The aim of this experiment was to investigate the effects of dietary crude protein (CP) contents and crystalline amino acids (CAA) supplementation patterns on growth performance, intestinal histomorphology, and immune response in weaned pigs under clean (CSC) or unclean sanitary conditions (USC). A total of 144 weaned pigs (6.35 ± 0.63 kg body weight) were assigned to 6 treatments in a 3 × 2 factorial arrangement based on CP content and sanitary conditions using a randomized complete block design, giving 8 replicates per treatment with 3 pigs per pen. Pigs were fed one of three diets for 21 d: one high CP (HCP; 22%) and two low CP (LCP; 19%) diets supplemented with 9 indispensable AA or only 6 AA (Lys, Met, Thr, Trp, Val, and Ile) as CAA. The CSC room was washed weekly, whereas the USC room had sow manure spread in the pens and was not washed throughout the experiment. Body weight and feed disappearance were recorded weekly. Blood was sampled from 1 pig per pen weekly, and the same pig was euthanized for jejunal tissues sampling on day 21. Pigs raised under USC had reduced (P < 0.05) average daily gain (ADG) and gain to feed ratio (G:F) in week 2, but contrary results that greater (P < 0.05) ADG and G:F were found in pigs under USC in week 3. Overall, there was an interaction where G:F did not differ between HCP and LCP under CSC, however, LCP decreased (P < 0.05) G:F compared to HCP under USC. Pigs fed the HCP diet had higher (P < 0.05) fecal scores than those fed the LCP diets throughout the experiment. Pigs fed the LCP had higher (P < 0.05) villus height to crypt depth ratio than those fed the HCP. An interaction was observed where goblet cell density in the jejunum was higher (P < 0.05) in pigs fed LCP than HCP under CSC, but no difference was found between HCP and LCP under USC. Different CAA supplementation patterns did not influence both growth performance and histomorphology. Pigs raised under USC had greater (P < 0.05) plasma interleukin (IL)-10 and IL-6 concentrations and reduced (P < 0.05) plasma tumor necrosis factor-alpha concentration. Also, the LCP diets resulted in a greater (P < 0.05) plasma IL-10 concentration. In conclusion, overall growth performance did not differ between HCP and LCP under CSC, but LCP diets reduced G:F under USC. Feeding LCP diets to weaned pigs improved gut morphology under USC and ameliorated systemic inflammation induced by USC, whereas CAA supplementation patterns did not affect growth performance and gut morphology.

Grape seed extract supplementation in heat-stressed preweaning dairy calves: I. Effects on antioxidant status, inflammatory response, hematological and physiological parameters

This study aimed to investigate the effects of grape seed extract (GSE) supplementation on antioxidant activity, inflammatory markers, hematological and physiological responses during the suckling period in heat-stressed calves. Sixty Holstein female calves (3 d of age, 40.6 ± 2.17 kg of BW) were randomly divided into four dietary groups. Each group consisted of 15 calves; the milk was supplemented with 0 (CON) 25 (GSE1), 50 (GSE2), and 100 (GSE3) mg/kg BW/day of GSE. On d 3, 33, and 63 blood samples were collected, rectal temperatures (RT) and respiratory rates (RR) were measured three days a week. Calves were exposed to chronic heat stress during the study period and were weaned on d 63. Plasma malondialdehyde (MDA) and tumor necrosis factor-alpha (TNF-α) concentrations decreased (P < 0.01) in all GSE supplemented groups compared to the CON group. Also, interferon-gamma (IFN-γ) concentration decreased (P = 0.03) only in calves fed GSE1. Plasma total antioxidant capacity (TAC) concentration increased (P = 0.02) in calves fed GSE3 on d 33 compared to the CON group, while the concentration of superoxide dismutase (SOD) was higher (P < 0.001) in the GSE2 and GSE3 groups compared to CON and GSE1. The hematocrit percentage, hemoglobin value, RBC, and eosinophil counts were higher (P < 0.01) in all GSE supplemented groups compared to CON. Calves fed GSE1, GSE2 and GSE3 had lower (P < 0.001) neutrophil count compared to CON on d 63. All GSE-supplemented groups had a decreased (P < 0.001) RR compared to CON, while calves fed GSE2 had a tendency to decrease (P = 0.10) in RT. It was concluded that supplementation with 50 and 100 mg/kg BW/d GSE could improve antioxidant, anti-inflammatory activities, and hematological parameters of calves against oxidative stress, and also reduce the effect of heat stress by reducing the respiratory rate.

513 Late-Breaking: Effects of Dietary Protein Content and Crystalline Amino Acid Supplementation Patterns on Gut Health of Weaned Pigs Raised Under Different Sanitary Conditions

Abstract The objective of this experiment was to investigate the effects of dietary crude protein (CP) content and crystalline amino acids (CAA) supplementation patterns on the histomorphology, immune response, and microbial metabolites in weaned pigs under clean (CSC) or unclean sanitary conditions (USC). One hundred forty-four piglets (6.35 ± 0.63 kg BW) were assigned to 1 of 3 diets: a high CP (HCP; 21%) and two low CP (LCP; 18%) diets supplemented with 10 crystalline indispensable amino acids (IAA) to meet all IAA requirements or only 6 IAA (Lys, Met, Thr, Trp, Val, and Ile) to meet IAA requirements except for Leu, His, and Phe. Each treatment had 8 replicates per sanitary condition with 3 pigs per pen. The CSC room was cleaned and washed weekly, whereas the USC room remained unwashed throughout the experiment and had sow manure spread in the pens. Data were analyzed using the MIXED procedure of SAS with orthogonal contrasts. Pigs fed the LCP diets had longer (P &amp;lt; 0.05) jejunal villi and higher villus height to crypt depth ratios than those fed the HCP diet. No significant difference is found in histomorphology between pigs fed LCP diets with different CAA supplementation patterns. Pigs raised under USC had greater (P &amp;lt; 0.05) plasma interleukin (IL)-10 and IL-6 concentrations and reduced (P &amp;lt; 0.05) plasma tumor necrosis factor-alpha concentration. Also, the LCP diets resulted in a greater (P &amp;lt; 0.05) plasma IL-10 concentration. Interactions (P &amp;lt; 0.05) between sanitation and dietary CP content were observed for goblet cell density and acetate and total volatile fatty acids contents in the jejunum. In conclusion, CAA supplementation patterns did not affect gut morphology in weaned pigs. Feeding LCP diets to weaned pigs improved gut morphology and microbial metabolites in jejunum under USC and ameliorated systemic inflammation induced by USC.

Effects of High and Low Molecular Weight Chitosan on Plasma Cholesterol, Glucose and Adipocytokines in Diabetic Rats Induced by Streptozotocin and Nicotinamide

Chitosan is known for its lipid-lowering effect. To investigate the comparative effects of low (LCS) and high molecular weight chitosan (HCS) on plasma glucose, cholesterol and adipocytokines, male Sprague-Dawley rats were divided into four groups: normal control, diabetic, and diabetic fed the HCS or LCS diet for seven weeks. Diabetes was induced by subcutaneous injection of nicotinamide and streptozotocin. Results showed that diabetic rats fed the HCS diet had reduced liver weight and perirenal adipose weight, compared to those that were fed the control diet. Higher fecal triglyceride and cholesterol excretion and lower hepatic cholesterol and triglyceride contents were found in diabetic rats fed with both chitosan diets. These observations were more significant in the HCS group than in the LCS group. HCS, but not LCS diet, significantly reduced plasma fructosamine, leptin, total cholesterol and lowered the insulin resistance index (homeostasis model assessment; HOMA) in diabetic rats. A lower intestinal dissaccharidase activity including sucrase and lactase was found in diabetic rats fed the HCS dict. Moreover, plasma tumor necrosis factor-alpha and plasminogen activator inhibitor-1 concentrations were significantly reduced by both chitosan supplementations. The results suggested that HCS feeding may reduce insulin resistance by the suppression of lipid accumulation in liver and adipose tissue and amelioration of chronic inflammation in diabetic rats. HCS may improve glucose and lipid metabolism more significantly than LCS in diabetic rats.

Effect of dexmedetomidine on intestinal injury in rats with endotoxemia

Objective To evaluate the effect of dexmedimidine on intestinal injury in rats with endotoxemia. Methods Twenty-four healthy adult male Sprague-Dawley rats, aged 2-3 months, weighing 200-250 g, were divided into 4 groups (n = 6 each) using a random number table method: control group (group C), endotoxemia group (group E), dexmedimidine group (group D) and dexmedimidine plus α7 subunit-containing nicotinic acetylcholine receptor antagonist group (D+ α-BGT group). The endotoxemia model was established by injecting lipopolysaccharide (LPS) 10 mg/kg via the femoral vein.Dexmedetomidine 40 μg/kg was injected and 15 min later LPS was intravenously injected in group D. Dexmedetomidine 40 μg/kg was intraperitoneally injected after intraperitoneal injection of α-bungarotoxin 1 μg/kg, and 15 min later LPS was intravenously injected in group D+ α-BGT.Blood samples were collected from the abdominal aorta at 6 h after LPS injection for determination of the plasma interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) concentrations (by enzyme-linked immunosorbent assay). Rats were sacrificed after blood sampling, and intestinal tissues were obtained for examination of the pathological changes and for determination of the myeloperoxidase (MPO) activity (by chemical colorimetry) and expression of NF-κB p65 in nucleoprotein (by Western blot). Results Compared with group C, the plasma IL-6 and TNF-α concentrations and MPO activity in intestinal tissues were significantly increased, and the expression of NF-κB p65 in nucleoprotein was up-regulated in the other 3 groups (P<0.05). Compared with group E, the plasma IL-6 and TNF-α concentrations and MPO activity in intestinal tissues were significantly decreased, the expression of NF-κB p65 in nucleoprotein was down-regulated (P<0.05), and the pathological changes of intestinal tissues were significantly attenuated in group D. Compared with group D, the plasma IL-6 and TNF-α concentrations and MPO activity in intestinal tissues were significantly increased, the expression of NF-κB p65 in nucleoprotein was up-regulated (P<0.05), and the pathological changes of intestinal tissues were accentuated in group D+ α-BGT. Conclusion Dexmedetomidine can reduce the intestinal injury in rats with endotoxemia, and the mechanism may be related to activating cholinergic anti-inflammatory pathway and further inhibiting inflammatory responses. Key words: Dexmetomidine; Endotoxemia; Intestines; Cholinergic anti-inflammatory pathway

Effects of mineralocorticoid receptor antagonists on responses to hemorrhagic shock in rats.

AIMTo evaluate the effects of mineralocorticoid receptor (MR) antagonists on mortality and inflammatory responses after hemorrhagic shock (HS) in rats.METHODSOne hundred and two male Sprague–Dawley rats were randomly assigned to one of the following three groups: Control, spironolactone (SPL), and eplerenone (EP) groups. HS was induced by the removal of blood. One half of rats were evaluated to determine mortality, hemodynamics, plasma tumor necrosis factor-alpha (TNF-α) concentrations, and arterial blood gas at 8 h after HS recovery. In the remainder of rats, the expression levels of genes encoding cytokines were evaluated in liver tissue samples at 1 h after HS recovery.RESULTSThe survival rates 8 h after HS recovery were 71%, 94%, and 82% in the control, SPL, and EP groups, respectively. There were no significant differences in survival rates among the three groups (P = 0.219). Furthermore, there were no significant differences in gene expression levels in the liver or plasma TNF-α concentrations among the three groups (P = 0.888).CONCLUSIONPretreatment with MR antagonists did not improve mortality or cytokine responses in the liver after HS recovery in rats.

Effect of transcutaneous electric acupoint stimulation on prognosis in patients at high risk of postoperative pulmonary complications

Objective To evaluate the effect of transcutaneous electric acupoint stimulation(TEAS)on prognosis in the patients at high risk of postoperative pulmonary complications. Methods Sixty American Society of Anesthesiologists physical status Ⅱ or Ⅲ patients of both sexes, aged 65-72 yr, with body mass index of 18-25 kg/m2, scheduled for elective thoracoscopic and laparoscopic radical resection of esophageal cancer, were divided into placebo control group(group C, n=30)and TEAS group(n=30). In group TEAS, bilateral Zusanli(ST36), Hegu(LI4)and Feishu(BL13)acupoints were stimulated for 30 min(disperse-dense waves, frequency 2/100 Hz, intensity of currents 8-12 mA)starting from 30 min before anesthesia induction.In group C, electrodes were placed on the same acupoints before anesthesia induction, but no current was given.General anesthesia was performed in two groups.Before one-lung ventilation, at 30 min and 2 h of one-lung ventilation and at 1 h after operation(T1-4), blood samples were drawn from the radial artery for blood gas analysis, and oxygenation index and alveolar-arterial oxygen partial pressure difference were calculated.Blood samples were collected from the internal jugular vein at T1-3 and 24 h after surgery(T5)for determination of plasma tumor necrosis factor-alpha, interleukin-6(IL-6)and IL-10 concentrations.The development of postoperative pulmonary complications, time for removal of drainage tube and length of hospital stay were recorded. Results Compared with group C, the oxygenation index at T2-4 and plasma IL-10 concentrations at T3 were significantly increased, the alveolar-arterial oxygen partial pressure difference at T2, 3, plasma tumor necrosis factor-alpha concentrations at T2, 3, plasma IL-10 concentrations at T3, 5 and incidence of postoperative pulmonary complications were decreased, and the time for removal of drainage tube and length of hospital stay were shortened in group TEAS(P<0.05). Conclusion TEAS can improve prognosis in the patients at high risk of postoperative pulmonary complications. Key words: Electric stimulation; Postoperative complications

Relationship between anesthetic factor and intestinal injury in patients undergoing cardiac surgery with cardiopulmonary bypass: a comparison of propofol- versus sevoflurane-based anesthesia

Objective To investigate the relationship between anesthetic factors and intestinal injury in the patients undergoing elective cardiac surgery with cardiopulmonary bypass (CPB). Methods Ninety American Society of Anesthesiologists physical status Ⅱ or Ⅲ patients of both sexes, aged 18-64 yr, with New York Heart Association grade Ⅱ or Ⅲ, undergoing elective cardiac surgery with CPB, were divided into 2 groups(n=45 each) using a random number table: propofol-based anesthesia group (group P) and sevoflurane-based anesthesia group (group S). CPB was established routinely after anesthesia induction.Before induction (T0), immediately after aortic unclamping (T1), at 30 min after aortic unclamping (T2) and at 2 h after discontinuation of CPB (T3), blood samples were collected from the radial artery for determination of the plasma endotoxin, D-lactic acid, diamine oxidase (DAO) and intestinal fatty acid-binding protein (I-FABP) concentrations (by enzyme-linked immunosorbent assay) and plasma interleukin-6 (IL-6), IL-8 and tumor necrosis factor-alpha (TNF-α) concentrations (using radio-immunity method). Results Compared with the baseline at T0, the concentrations of plasma endotoxin, D-lactic acid, DAO, TNF-α, IL-6, IL-8 and I-FABP were significantly increased at T1-T3 in both groups (P<0.05). Compared with group P, the concentrations of plasma endotoxin, D-lactic acid, DAO, TNF-α, IL-6, IL-8 and I-FABP were significantly decreased at T1-T3 in group S(P<0.05). Conclusion Anesthetic factors are related to intestinal injury in patients undergoing cardiac surgery with CPB.Compared with propofol-based anesthesia, sevoflurane-based anesthesia is helpful in reducing the inflammatory response and in decreasing the degree of intestinal injury and is more suitable for the cardiac surgery with CPB. Key words: Anesthesia, general; Propofol; Cardiopulmonary bypass; Intestinal mucosa; Wounds and injuries; Sevoflurane

Effects of ABO blood group factors on erythrocyte suspension transfusion reactions

Objective To investigate the effects of ABO blood group factors on erythrocyte suspension(RCS)transfusion reactions in patients. Methods Test Ⅰ A total of 12 600 patients in whom RCS was transfused during operation at the department of anesthesiology of 11 hospitals of Inner Mongolia from January 2006 to January 2014 were selected.The occurrence of transfusion reactions(fever [an increase in body temperature>1 ℃ than that before transfusion], allergy, hemolysis)was recorded in the patients.Test Ⅱ A total of 120 RCS-transfused patients of both sexes, aged 18-55 yr, weighing 45-75 kg, of American Society of Anesthesiologists physical statusⅠ or Ⅱ, who underwent surgical operation, were divided into 4 groups(n=30 each)according to the blood group: blood group A group(group A), blood group B group(group B), blood group O group(group O)and blood group AB group(group AB). The standard for RCS transfusion was defined as hemoglobin(Hb) 10 g/L.Before induction of anesthesia(T1), before blood transfusion(T2), and at 5 min, and 1, 6 and 24 h after blood transfusion(T3-6), blood samples were collected from the central vein for determination of the plasma tumor necrosis factor-alpha(TNF-α), interleukin-4(IL-4)and IL-10 concentrations by enzyme-linked immunosorbent assay. Results Among the 12 600 RCS-transfused patients, 216 cases developed transfusion reactions, and the incidence of transfusion reactions was 1.714%.For the patients of different blood groups, the incidence of transfusion reactions from the high to the low was blood group B, blood group AB, blood group A, and blood group O in turn(P<0.05 or 0.01). Compared with group B, the plasma TNF-α and IL-10 concentrations were significantly decreased, and the plasma IL-4 concentrations were increased at T3-T6 in the other three groups(P<0.05). Compared with group AB, the plasma TNF-α and IL-10 concentrations were significantly decreased, and the plasma IL-4 concentrations were increased at T3-T6 in A and O groups(P<0.05). Compared with group O, the plasma TNF-α and IL-10 concentrations were significantly decreased, and the plasma IL-4 concentrations were increased at T3-T6 in group A(P<0.05). Conclusion ABO blood group factors affect RCS transfusion reactions in the patients, and the incidence of transfusion reactions from the high to the low is blood group B, blood group AB, blood group A, and blood group O in turn. Key words: ABO blood-group system; Blood component transfusion

Elevated plasma and cerebrospinal fluid interleukin-1 beta and tumor necrosis factor-alpha concentration and combined outcome of death or abnormal neuroimaging in preterm neonates with early-onset clinical sepsis.

Prematurity and sepsis are the major contributors of neonatal mortality and neurodevelopmental sequelae. The present study was conducted to measure the plasma and cerebrospinal fluid (CSF) concentration of interleukin (IL)-1β and tumor necrotic factor (TNF)-α in preterm neonates with early-onset clinical sepsis (EOCS), and to find out their association with combined outcome of death or abnormal neuroimaging. Thirty-two preterm (⩽34 weeks) neonates with EOCS and 32 gestational age-matched, healthy neonates served as cases and controls, respectively. Samples were collected soon after birth. Neonates were followed up clinically and by serial cranial ultrasonography (CUS) until discharge and subsequently by magnetic resonance imaging (MRI) of brain until 1 year. Developmental screening was done by Denver Developmental Screening test-II. In EOCS group, no neonate had any clinical/microbiological evidence of meningitis. Blood culture was positive in 17 (53%). CUS was abnormal in 12 (37%) (intracranial hemorrhage-11, periventricular leukomalacia-1). Ten (31%) neonates expired. Significant elevation of plasma and CSF IL-1β and TNF-α was observed in the EOCS group. On follow-up, seven (22%) neonates showed evidence of white matter damage in MRI, two of them had developmental delay and microcephaly. Plasma and CSF IL-1β and TNF-α concentration were significantly elevated in deceased neonates and those with abnormal neuroimaging. Both biomarkers demonstrated high predictive accuracy for poor outcome in receiver-operating curve analysis. Elevation of plasma and CSF IL-1β and TNF-α is associated with an increase in the combined outcome of death or abnormal neuroimaging in preterm neonates with EOCS in the absence of clinical/microbiological evidence of meningitis with high predictive accuracy.

Effects of Octreotide in Chronically Mild Stressed Rats: Possible Role of Immune and Oxidative Stress Pathways

Impairment of neuroendocrine, immune and antioxidant defenses contribute to pathophysiology of stress-induced depression. Somatostatin executes diverse regulatory effects on endocrine, exocrine and neural functions; however, the possibility that octreotide, a synthetic somatostatin analogue might mitigate stress-induced depression remains elusive. Hence, the current study aimed to explore the immunomodulatory and antioxidant effects of octreotide in a model of chronic mild stress (CMS). This paradigm was performed by exposing rats to a combination of mild unpredictable stressors for 21 days. Fifty male Wistar rats were divided into five groups; (1) control receiving saline, (2) octreotide given to normal unstressed animals. The remaining three groups were subjected to (3) CMS alone or in combination with octreotide (4) 50 μg/kg or (5) 90 μg/kg. Octreotide increased sucrose preference index and attenuated CMS-induced increases in plasma adrenocorticotrophic hormone and corticosterone levels. In addition, octreotide decreased plasma tumor necrosis factor-alpha concentration. Moreover, it prevented CMS-induced oxidative damage by enhancing the antioxidant defenses superoxide dismutase, glutathione reductase and glutathione in the hippocampus. Furthermore, octreotide normalized the elevated malondialdehyde and lactate dehydrogenase levels in the hippocampus. These results demonstrate a possible antidepressant-like activity of octreotide in CMS due to its antioxidant/antiinflammatory aptitude.

Dose- and time-related effects of dexmedetomidine on mortality and inflammatory responses to endotoxin-induced shock in rats

Our previous study demonstrated that dexmedetomidine drastically reduced mortality and inhibited the inflammatory response during endotoxemia in rats. The aim of this study was to clarify the dose- and time-related effects of dexmedetomidine on mortality and inflammatory responses to endotoxemia in rats. Male Wistar rats (n = 96) were anesthetized intraperitoneally with pentobarbital sodium and assigned to one of two protocols: one representing the dose-related effects of dexmedetomidine, and the other, the time-related effects of dexmedetomidine. To evaluate the dose-related effects, the animals were randomly assigned to one of four groups (n = 15 each): endotoxemic group (group E), receiving intravenous Escherichia coli endotoxin (15 mg x kg(-1) over 2 min); small-dose group (group S), treated with a small dose of dexmedetomidine (2.5 microg x kg(-1) x h(-1), IV); medium-dose group (group M), treated with a medium dose (5 microg x kg(-1) x h(-1), IV); and large-dose group (group L), treated with a large dose (10 microg x kg(-1) x h(-1), IV). To evaluate the time-related effects, the animals were randomly assigned to one of three groups (n = 12 per group): endotoxemic group; early posttreatment group, treated with 10 microg x kg(-1) x h(-1) dexmedetomidine at 1 h after endotoxin injection; and late posttreatment group, treated with 10 microg x kg(-1) x h(-1) at 2 h after endotoxin injection. Hemodynamics and arterial blood gases were recorded and plasma cytokine concentrations were measured throughout the observation period. The mortality rate was assessed up to 8 h after endotoxin injection. In the dose-related study, the mortality rates at 8 h after endotoxin injection were 81%, 26%, 32%, and 20% for groups E, S, M, and L, respectively. Plasma tumor necrosis factor-alpha (TNF) concentrations were lower in groups M and L than in group E at 2 h after endotoxin injection. Plasma interleukin-6 (IL-6) concentrations were lower in groups M and L than in group E at 4 and 5 h after endotoxin injection. In the time-related study, the mortality rates at 8 h after the endotoxin injection were 83%, 33%, and 58% for the endotoxemic, early posttreatment, and late posttreatment groups, respectively. The TNF concentration was lower in the early posttreatment group than in the endotoxemic group at 2 h after endotoxin injection, and the IL-6 concentration was lower in the early posttreatment group than in the endotoxemic group at 5 h after endotoxin injection. Dexmedetomidine dose-dependently attenuated extremely high mortality rates and increases in plasma cytokine concentrations after endotoxin injection. Moreover, the early administration of dexmedetomidine drastically reduced the high mortality rate and inhibited cytokine responses in endotoxin-exposed rats. These findings suggest that dexmedetomidine administration may be effective during sepsis.

Short Communication: Changes in Micromineral, Magnesium, Cytokine, and Cortisol Concentrations in Blood of Dairy Goats Following Intramammary Inoculation with Staphylococcus aureus

The aim of this study was to investigate mineral metabolism and immune response in dairy goats following intramammary inoculation with varying doses of Staphylococcus aureus. Blood samples were collected at 0, 2, 4, 8, 12, 24, 48, and 72h after intramammary inoculation. Lowered plasma Fe concentrations were observed from 12 to 24h postinoculation in groups SAA (Staph. aureus at 104 cfu, n = 5) and SAB (Staph. aureus at 108 cfu, n = 5). Plasma Cu concentrations increased in group SAB 2h after inoculation and maintained greater concentrations until the end of the experiment compared with the control group (phosphate-buffered saline, n = 5). Increased plasma Zn concentrations in group SAB were observed 48h after inoculation, and the concentration was still greater 72h after inoculation compared with the control group. Greater plasma Mg concentrations were detected in groups SAA and SAB compared with the control group at all timepoints after inoculation. Plasma Mg concentrations were generally greater in group SAA than in group SAB through 72h (except at 2h). Plasma tumor necrosis factor-alpha concentrations were unchanged following intramammary inoculation with Staph. aureus throughout the study. Plasma IL-6 concentrations in groups SAA and SAB increased gradually compared with the control group and peaked at 48h after inoculation. In group SAB, serum cortisol concentrations started to increase from 8h postinoculation and peaked at 12h postinoculation. In conclusion, increasing the inoculum dose does not induce more rapid proinflammatory cytokine responses, whereas the data indicate that mineral metabolic alterations occur during the course of Staph. aureus mastitis in the goat.

Efficacy of colistin/rifampin combination in experimental rat models of sepsis due to a multiresistant Pseudomonas aeruginosa strain*

To investigate the efficacy of rifampin and colistin in three experimental rat models of Pseudomonas aeruginosa sepsis. Prospective, randomized, controlled animal study. Research laboratory in a university hospital. Adult male Wistar rats. Adult male Wistar rats were given a) an intraperitoneal injection of 1 mg of P. aeruginosa 10 lipopolysaccharide; b) 2 x 10(10) colony-forming units of P. aeruginosa ATCC 27853; and c) 2 x 10(10) colony-forming units of one clinically multiresistant strain of P. aeruginosa. For each model, all animals were randomized to receive intravenously isotonic sodium chloride solution, 10 mg/kg rifampin, 1 mg/kg colistin, and 10 mg/kg rifampin plus 1 mg/kg colistin. Lethality, bacterial growth in blood and peritoneum, and endotoxin and tumor necrosis factor-alpha concentrations in plasma were measured. Colistin exerted a strong antimicrobial activity and achieved a significant reduction of plasma endotoxin and tumor necrosis factor-alpha concentration compared with control and rifampin-treated groups. Rifampin exhibited no antimicrobial activity with no substantial impact on endotoxin and tumor necrosis factor-alpha plasma concentrations. The combination of colistin and rifampin resulted in a significant reduction in bacterial count compared with colistin monotherapy, whereas no significant difference was found in positive hem cultures and mortality rates between the two groups. Colistin and rifampin might have a role in the therapy of multiresistant P. aeruginosa infection.

Amphibian peptides prevent endotoxemia and bacterial translocation in bile duct–ligated rats*

To investigate the efficacy of amphibian antimicrobial peptides in preventing bacterial translocation and neutralizing endotoxins in bile duct-ligated rats. Prospective, randomized, controlled animal study. Research laboratory in a university hospital. Adult male Wistar rats. Adult male Wistar rats underwent sham operation or bile duct ligation (BDL). Eight groups were studied: sham operation with saline treatment, sham operation with 120 mg/kg tazobactam-piperacillin, sham operation with 2 mg/kg uperin 3.6, sham operation with 2 mg/kg magainin2, BDL with saline treatment, BDL with 120 mg/kg tazobactam-piperacillin, BDL with 2 mg/kg uperin 3.6, and BDL with 2 mg/kg magainin2. Main outcome measures were: endotoxin and tumor necrosis factor-alpha concentrations in plasma and evidence of bacterial translocation in blood, peritoneum, liver, and mesenteric lymph nodes. Endotoxin and tumor necrosis factor-alpha plasma levels were significantly higher in BDL rats compared with sham-operated animals. All amphibian peptides achieved a significant reduction of plasma endotoxin and tumor necrosis factor-alpha concentration when compared with saline- and tazobactam-piperacillin-treated groups. On the other hand, both tazobactam-piperacillin and peptides significantly reduced bacterial growth compared with the control. Tazobactam-piperacillin and magainin2 exerted the maximal inhibition of bacterial growth. In conclusion, because of their multifunctional properties, amphibian peptides could be interesting compounds to inhibit bacterial translocation and endotoxin release in obstructive jaundice.

Cathelicidin peptide sheep myeloid antimicrobial peptide-29 prevents endotoxin-induced mortality in rat models of septic shock.

The present study was designed to investigate the antiendotoxin activity and therapeutic efficacy of sheep myeloid antimicrobial peptide (SMAP)-29, a cathelicidin-derived peptide. The in vitro ability of SMAP-29 to bind LPS from Escherichia coli 0111:B4 was determined using a sensitive limulus chromogenic assay. Two rat models of septic shock were performed: (1) rats were injected intraperitoneally with 1 mg E. coli 0111:B4 LPS and (2) intraabdominal sepsis was induced via cecal ligation and single puncture. All animals were randomized to receive parenterally isotonic sodium chloride solution, 1 mg/kg SMAP-29, 1 mg/kg polymyxin B or 20 mg/kg imipenem. The main outcome measures were: abdominal exudate and plasma bacterial growth, plasma endotoxin and tumor necrosis factor-alpha concentrations, and lethality. The in vitro study showed that SMAP-29 completely inhibited the LPS procoagulant activity at approximately 10 microM peptide concentration. The in vivo experiments showed that all compounds reduced the lethality when compared with control animals. SMAP-29 achieved a substantial decrease in endotoxin and tumor necrosis factor-alpha plasma concentrations when compared with imipenem and saline treatment and exhibited a slightly lower antimicrobial activity than imipenem. No statistically significant differences were noted between SMAP-29 and polymyxin B. SMAP-29, because of its double antiendotoxin and antimicrobial activities, could be an interesting compound for septic shock treatment.

Leptin, tumor necrosis factor-alpha (TNF), and CD14 in ovine adipose tissue and changes in circulating TNF in lean and fat sheep.

Four studies were designed to determine whether 1) tumor necrosis factor-alpha (TNF) and the Lipopolysaccharide (LPS) binding ligand, CD14, are produced by sheep adipose tissue; 2) nutritional reserves and/or short-term fasting affect circulating concentrations of TNF; 3) there is a relationship between TNF and metabolic factors in sheep; and 4) inflammation alters circulating concentrations of leptin. In Exp. 1 and 2, ewes were assigned, based on ultrasonic assessments of last-rib subcutaneous fat measurements to fat (fat thickness > 1 cm; mean = 1.52 +/- 0.03 cm) or thin (fat thickness < 1 cm; mean = 0.25 +/- 0.03 cm) groups. Fat and thin ewes were assigned to fed or fasted groups for a total of four groups (fed-fat; fasted-fat; fed-thin; fasted-thin). Fed-ewes had ad libitum access to feed, and fasted-ewes were prohibited feed 48 h before initiation of sample collection. In Exp. 1, subcutaneous fat samples were collected from just above the last rib for detection of TNF and CD14 mRNA, and immunoreactivity. Tumor necrosis factor-alpha-like immunoreactivity in adipocytes was sparse, more pronounced in cells in fed-ewes than fasted-ewes, and localized to membranes between adjacent cells in nucleated regions. Immunoreactivity for CD14 was minimally observed but present in adipocytes and widely expressed in infiltrating monocytes and epithelial vascular cells. Leptin was detected in adipocytes. In Exp. 2, plasma samples collected every 6 h for 24 h were analyzed for plasma concentrations of TNF. Fat ewes had greater plasma concentrations of TNF than thin ewes (P = 0.039). In Exp. 3, wethers were injected i.v. with interleukin-1beta or TNF. Blood samples were collected every 15 min for 8 h following injection. Plasma concentration of leptin was not affected by treatment (P > 0.39). In Exp. 4, wethers were injected with LPS. Blood samples were collected every 15 min for 8 h following injection. Plasma concentration of leptin was not altered by LPS (P > 0.20). These results provide evidence: 1) of TNF-like immunoreactivity within fat tissue; 2) that elements within fatty tissues have CD14 that may allow adipocyte function to be directly affected by LPS; 3) that plasma concentrations of leptin are not altered by LPS treatment; and 4) that circulating concentrations of TNF are elevated with obesity in sheep.

Estradiol plus progesterone treatment modulates select elements of the proinflammatory cytokine cascade in steers: attenuated nitric oxide and thromboxane B2 production in endotoxemia.

Estradiol plus progesterone (EP) implants have been shown to favorably alter the time course or decrease the severity of many of the clinical manifestations associated with coccidiosis and endotoxemia in calves. This study evaluated the effect of EP treatment on plasma tumor necrosis factor-alpha (TNF), thromboxane (TXB), prostacyclin (PRC), nitrite and nitrate (NO[x]), and cortisol. Holstein steer calves were divided into four groups: control, EP, endotoxin (LPS), and EP + LPS (n = five/group). Estradiol/progesterone pellets (Synovex-S) were implanted subcutaneously when calves reached 20 wk of age. One week after implantation, calves were injected i.v. with endotoxin (i.e., lipopolysaccharide; LPS, 0.6 microgram/kg of BW) or nonpyrogenic saline placebo. Body temperature was measured and blood was collected before injection and at 1, 2, 3, 4, 6, and 8 h thereafter. Plasma concentrations of TNF, cortisol, TXB, PRC, NO[x], were measured. Body temperature increased in both LPS and LPS-EP calves, but had returned to normal by 6 h in the LPS-EP group (P < 0.05). Plasma TNF and cortisol increased after LPS (P < 0.01), but were not differentially affected by EP treatment. Likewise, EP did not affect the magnitude of increase in LPS-induced PRC, but EP decreased the magnitude of increase in TXB (P < 0.05). Plasma NO[x]) levels were increased (P < 0.01) in calves after LPS; treatment with EP attenuated the LPS-associated increase in plasma NO[x] levels. These results suggest that EP exerts specific effects on different components of the proinflammatory cytokine cascade. Although the initiation of responses mediated by TNF, cortisol, and PRC do not seem to be differentially affected by EP, components of the nitric oxide- and TXB-axis responses to LPS are decreased in calves pretreated with EP.

Impact of estradiol on parametrial adipose tissue function: evidence for establishment of a new set point of leptin sensitivity in control of energy metabolism in female rat.

Estradiol has been implicated in the regulation of food intake; however, its effect seems to be exerted in a bimodal fashion. We examined whether a single im injection of estradiol valerate (E2V), lastingly effective, could induce changes in parametrial fat function that further induce a new set point of leptin sensitivity in the female rat. E2V induced severe anorexia and loss of body weight between d 4 and 12 posttreatment. E2V rats recovered normal food intake and departing body weights on wk 2 and 3 posttreatment, respectively; however, they did not reach body weights of control rats. On d 61 posttreatment, we found that unfasting E2V, vs control, rats displayed increased E2 and leptin circulating levels; reduced plasma tumor necrosis factor-alpha(TNF-alpha) concentrations; similar circulating levels of glucose, insulin, and triglyceride; and lower parametrial fat mass containing a higher number of adipocytes that, although normal in size, in vitro released more leptin. Metabolic responses to fasting indicated that unlike control animals, E2V rats did not decrease triglyceride circulating levels, and that both groups decreased plasma glucose, leptin, and insulin, but not TNF-alpha, levels. High glucose load experiments indicated that E2V animals displayed a better insulin sensitivity than control rats; did not significantly increase circulating leptin concentrations as control rats did; and, unlike control, significantly decreased plasma triglyceride levels. Our data strongly support a potent acute anorectic effect of E2 and that, after several weeks, E2 modified parametrial fat function and insulin sensitivity, protecting the organism against future unfavorable metabolic conditions.

Lower Limb Ischemia‐Reperfusion Injury Triggers a Systemic Inflammatory Response and Multiple Organ Dysfunction

Restoration of blood flow to an acutely ischemic lower limb may, paradoxically, result in systemic complications and unexpected mortality. We investigated the effect of acute ischemia-perfusion of the lower limb on cytokine production and end organ function. Plasma concentrations of tumor necrosis factor-alpha (TNF-a) and interleukin-6 (IL-6) were determined in five groups of male Wistar rats: control, 3 hours of bilateral hind limb ischemia alone, and 3 hours of bilateral hind limb ischemia followed by 1 hour, 2 hours, or 3 hours of reperfusion, respectively. In a second experiment, the effect of lower limb ischemia-reperfusion on remote organs (lung, liver, and kidney) was assessed biochemically and histologically. There was a significant increase in plasma concentrations of TNF-a in plasma of animals subjected to 3 hours of bilateral hind limb ischemia followed by 1 hour of reperfusion, 40.1 +/- 4.4 pg/ml, when compared with controls, 22.6 +/- 4.4 pg/ml, or animals in the ischemia-alone group, 16.3 +/- 5.2 (p <0.05). Plasma concentration of IL-6 increased progressively and significantly in animals subjected to bilateral hind limb ischemia followed by 1 hour of reperfusion, 720 +/- 107 pg/ml; 2 hours of reperfusion, 1987 +/- 489 pg/ml; or 3 hours of reperfusion, 6284 +/- 1244 (p <0.0001), compared with controls, 104 +/- 43 pg/ml; or animals in the ischemia-alone group, 140 +/- 55 pg/ml. In the study comparing portal and systemic concentrations of IL-6, systemic concentrations of IL-6, 967 +/- 184 pg/ml were significantly higher than those in the portal circulation 577 +/- 127 pg/ml (p <0.05). There was a significant increase in plasma concentrations of urea, creatinine, aspartate transaminase, alanine transaminase, and lactic dehydrogenase in reperfused animals compared with controls (p <0.001). Morbidity and mortality following reperfusion of the acutely ischemic limb may be a manifestation of multiple organ dysfunction caused by a systemic inflammatory response triggered by reperfusion of the ischemic extremities.