View clinical trials related to Endotoxemia.
Filter by:Excessive inflammation is associated with tissue damage caused by over-activation of the innate immune system. This can range from mild disease to extreme conditions such as multiple organ failure (MOF). In marked contrast to adaptive immunity which is very sensitive to immune modulators such as steroids, the innate immune system cannot be sufficiently targeted by currently available anti-inflammatory drugs. We hypothesize that C1-esterase inhibitor can modulate the innate immune response. In this study, human endotoxemia will be used as a model for inflammation. Subjects will, additionally to endotoxin, receive C1 esterase inhibitor or placebo. Blood will be sampled to determine the levels of markers of the innate immune response.
Rationale: The vagus nerve exerts an anti-inflammatory effect in in vitro and animal experiments. This 'vagal anti-inflammatory pathway' is mediated by the nicotinergic α7nACh receptor that can be selectively stimulated by GTS-21. Activation of the cholinergic anti-inflammatory pathway via vagus nerve stimulation or α7nAChR agonists improves outcome in animal models of endotoxemia, sepsis and experimental arthritis. Up to now, the anti-inflammatory effects of oral administration of GTS-21 in humans in vivo has not been investigated. Objective: Primary aim: to investigate the anti-inflammatory effects of oral administration of GTS-21 on the inflammatory response in the human endotoxemia model and the subsequent inflammation-induced subclinical organ dysfunction. Secondary aim: to measure the effect of LPS administration in the absence or presence of GTS-21 in human volunteers on vagal nerve activity measured by heart rate variability analysis. Study design: Double-blind placebo-controlled randomized cross-over intervention study in healthy human volunteers during experimental endotoxemia. Study population: Non-smoking healthy male volunteers, age 18-35 yrs Intervention: Subjects will be tested in a cross-over design in 2 separate sequential sessions, 2-4 weeks apart. A total of 12 subjects will be randomly assigned to one of two dosing groups in a 1:1 ratio: GTS-21 followed by Placebo n=6, Placebo followed by GTS-21 n=6. Subjects will receive 150mg GTS-21 or placebo orally tid 3 days before LPS injection and an oral dose of 150 mg GTS-21 or placebo the morning of the day of LPS administration (07:00 AM). Subjects will then receive an oral dose of 150 mg GTS-21 or placebo at 08:00 AM and another oral dose of 150 mg GTS-21 or placebo at 1 hour before LPS administration (t=0). Before LPS injection, prehydration will be performed by infusion of 1.5 L 2.5% glucose/0.45% saline solution in 1 hour. One hour after the last dose of GTS-21 or placebo, LPS derived from E coli O:113 will be injected (2 ng/kg iv in 1 minute). There will be a 14 day washout period for patients in all groups. The last group of subjects will be subjected to an identical dose of LPS and placebo at two different moments 2-4 weeks apart to obtain time controls. Main study parameters/endpoints: Main study endpoint is the concentration of circulating cytokines after LPS in the absence and presence of GTS-21. Nature and extent of the burden and risks associated with participation, benefit and group relatedness: A medical interview and physical examination is part of this study. Approximately 350 ml blood will be withdrawn and urine will be collected. There will be mild discomfort associated with participation in this study, as LPS induces flu-like symptoms for approximately 4 hrs. GTS-21 was found to be well tolerated at a dose of 150 mg three times daily (450 mg/day).
Epinephrine (adrenaline) is a substance produced by the body (in the adrenal gland) in response to stress such as infection or injury. Endotoxin is a man- made substance, which causes the body to "mimic" sickness (fever, chills, and achiness) for a few hours. This study is designed to give epinephrine before and/or after endotoxin to determine if this medication can prevent or relieve any of the symptoms caused by endotoxin.
The adenosine receptor is known for its anti-inflammatory actions and could therefore be a potential target in the treatment of sepsis and septic shock. Stimulation of the adenosine receptor could potentially lead to a decrease in inflammation and tissue damage. Under normal conditions adenosine is formed either by an intracellular 5`nucleotidase, which dephosphorylates AMP, or by the hydrolysis of S-adenosylhomcysteine by hydrolase. An alternative pathway of AMP degradations is provided by the cytosolic enzyme AMP deaminase (AMPD), which catalyses the irreversible deamination of AMP to inosine monophosphate and ammonia. In humans four AMPD isoforms have been described, named after the source from which they were initially purified; M (muscle), L (liver), E1 and E2 (erythrocyte), encoded by AMPD1, AMPD2 and AMPD3. Approximately 15-20% of Caucasian and African American individuals are heterozygous or homozygous for the 34C>T variant of AMPD1. We hypothesize that healthy volunteers who have the polymorphism for AMPD1 have a less severe inflammatory response to LPS and show less (severe) organ failure. This hypothesis is based on the expected higher levels of adenosine in patients with the AMPD1 polymorphism. This hypothesis is strengthened by the fact that patients with coronary artery disease and the AMPD1 polymorphism show improved cardiovascular survival (Anderson JL et al. J Am Coll Cardiol 2000; 36: 1248-52) possibly based on higher adenosine levels by reduced AMPD activity. Furthermore the polymorphism predicts improved clinical outcome in patients with heart failure (Loh E et al. Circulation 1999) also based on a hypothetical elevation of adenosine. We hypothesize that: The C34T-polymorphism of the enzyme AMP-deaminase leads to a decreased inflammatory respons and thereby a decrease of LPS-induced tissue damage. A second hypothesis is based on the antagonism of the adenosine receptor, by caffeine; Antagonism of the adenosine receptor by caffeine leads to an increased LPS-induced inflammatory reaction and an increase in (subclinical) tissue damage?
The aim of the present protocol is to study gene activity in fat and muscle tissue in type 2 diabetics and healthy volunteers after injection of E. coli endotoxin.We hereby hope to gain insight in some mechanisms behind the association between inflammation and insulin resistance.
The objective of the present protocol is to study whether a low level of oxygen in the blood will affect the immune response to as well as cerebral blood flow and metabolism during an infection and, conversely, whether the acute systemic and cerebral physiologic response to hypoxia is modified by an ongoing inflammatory response.
The purpose of this study is to determine the effects of HMG-CoA reductase inhibitor pretreatment on inflammation and coagulation activation in human endotoxemia.
The purpose of this study is to investigate putative ethnic differences in the proinflammatory response in human endotoxemia.
A number of diseases lead to a so called systemic inflammatory response syndrome (SIRS). This excessive response is self-destructive and leads to major complications of the initial disease: dysfunction of the microcirculation, systemic vasodilation, and increased capillary leakage and oedema. Animal studies have shown that pre-treatment with endotoxin (lipopolysaccharide or LPS) suppress the excessive immune response and when rechallenged, the animal survive a normally lethal dose of endotoxin. Besides a diminished cytokine response, an increased production of leucocytes in the bone marrow and an increased phagocytosis after pre-treatment with endotoxin is seen. The combination of these factors: diminished systemic inflammatory response and increased cellular immunity makes that endotoxin tolerance is a useful tool for preventing the complications after an excessive inflammatory response. Further, the presence of cross-tolerance has also been shown: Endotoxin tolerant mice survive more after induction of a normally lethal fungal infection. Endotoxin tolerance is also protective for ischemia/reperfusion injury in kidneys, heart and liver. Little data is known about endotoxin tolerance in human. The purpose of this study is to induce a state of tolerance through 2 different administration schedules and monitor the effect of tolerance on pro- and anti-inflammatory cytokines, other inflammatory parameters and different proteins involved in the signalling pathway. The effects of tolerance on vascular reactivity will be determined. Finally, the effect of tolerance on ischemia-reperfusion injury will be investigated.
Background: Activation of NO-synthase and vascular potassium (K) channels may play a role in the sepsis-induced attenuated sensitivity to norepinephrine. We examined whether various K channel blockers and NO-synthase inhibition could restore norepinephrine sensitivity during experimental human endotoxemia.