Related Experiment Video
Updated: Jul 28, 2026
11:44
Stimulation of Cytoplasmic DNA Sensing Pathways In Vitro and In Vivo
Published on: September 18, 2014
Pyrogen sensing and signaling: old views and new concepts.
1Department of Physiology, University of Tennessee, Memphis, TN 38163, USA. blatteis@physio1.utmem.edu
Summary
Bacterial lipopolysaccharides (LPS) trigger fever through rapid, early mediators, potentially via neural pathways, before detectable cytokines or cyclooxygenase-2 expression. This challenges traditional pyrogen signaling models.
Area of Science:
- Neuroscience
- Immunology
- Physiology
Background:
- Fever is traditionally linked to pyrogenic cytokines acting on the brain's preoptic-anterior hypothalamic area (POA).
- Prostaglandin E2 (PGE2) is considered a key mediator in the POA, induced by these cytokines.
Purpose of the Study:
- To review current understanding of pyrogen signaling in fever induction.
- To present novel hypotheses on how lipopolysaccharides (LPS) initiate fever, considering early mediator events.
Main Methods:
- Review of existing literature on fever pathophysiology.
- Analysis of the temporal relationship between LPS administration, mediator detection, and fever onset.
- Exploration of potential neural signaling pathways in fever.
Main Results:
- PGE2 production and fever onset occur before detectable cytokine levels or cyclooxygenase-2 expression post-LPS administration.
- This temporal discrepancy suggests that cytokines may not be the sole or primary initiators of early fever responses.
Conclusions:
- The traditional model of cytokine-induced fever may be incomplete, particularly regarding the rapid initiation phase.
- Alternative, faster-acting mediators and neural pathways are likely involved in the initial stages of LPS-induced fever.
More Related Videos
04:34Mouse Body Temperature Measurement Using Infrared Thermometer During Passive Systemic Anaphylaxis and Food Allergy Evaluation
Published on: September 14, 2018
07:42Fluorescence Assays for the Study of Mycobacterium tuberculosis Interaction with the Immune Receptor SLAMF1
Published on: February 28, 2025
Related Concept Videos
01:30Bacterial Signaling
Bacterial signaling can occur within bacteria (intracellular) or between bacteria (intercellular). At times, a group of bacteria behaves like a community. To achieve this, they engage in quorum sensing, the perception of higher cell density that causes changes in gene expression. Quorum sensing involves both extracellular and intracellular signaling. The signaling cascade starts with a molecule called an autoinducer (AI). Individual bacteria produce AIs that move out of the bacterial cell...
01:43Thermosensation
Peripheral thermosensation is the perception of external temperature. A change in temperature (on the surface of the skin and other tissues) is detected by a family of temperature-sensitive ion channels called Transient Receptor Potential, or TRP, receptors. These receptors are located on free nerve endings. Those detecting cold temperatures are closer to the surface of the skin than the nerve endings detecting warmth. These thermoTRP channels, while temperature selective, have relatively...
02:28Leaky Scanning
During most eukaryotic translation processes, the small 40S ribosome subunit scans an mRNA from its 5' end until it encounters the first start AUG codon. The large 60S ribosomal subunit then joins the smaller one to initiate protein synthesis. The location of the translation initiation is largely determined by the nucleotides near the start codon as there may be multiple translation initiation sites present on the mRNA. Marilyn Kozak discovered that the sequence RCCAUGG (where R stands for...
02:26NF-κB-dependent Signaling Pathway
The transcription factor NF-κB was discovered in 1986 in the lab of Nobel laureate Professor David Baltimore, for its interaction with the immunoglobulin light chain enhancer in B-cells. After more than three decades of study, it is now evident that NF-κB regulates the expression of over 100 genes. Most of these genes play an essential role in the innate and adaptive immune responses as well as the inflammatory responses of animals.
NF-κB-dependent Signaling Mechanism
The heterodimer of NF-κB...
NF-κB-dependent Signaling Mechanism
The heterodimer of NF-κB...
01:25Increased Body Temperature
A body temperature above 38°C (100.4 °F) is known as fever or pyrexia, and a person with fever is termed 'febrile.' Typically, the hypothalamus, a part of the brain that acts as the body's thermostat, regulates body temperature through a thermoregulatory setpoint. It receives signals from cold and warm thermal receptors throughout the body and adjusts the body's temperature accordingly. Fever occurs when this hypothalamic setpoint is altered, usually in response to an infection or illness.
01:28Regulation of Bacterial Virulence
Pathogenic bacteria employ a range of regulatory mechanisms to modulate the expression of virulence genes in response to environmental and host-derived signals. These mechanisms ensure that virulence factors are expressed only under favorable conditions, thereby optimizing infection and survival strategies.Mechanisms of Virulence RegulationKey regulatory strategies include:Two-Component Systems: These consist of a membrane-bound sensor kinase and a cytoplasmic response regulator. Environmental...