What are inflammatory mediators?

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From the Guidelines

Inflammatory mediators are a complex array of molecules, including cytokines, chemokines, and other signaling molecules, that play a crucial role in coordinating the body's immune response to injury or infection, as highlighted in a 2021 consensus statement on the treatment of immune-mediated inflammatory diseases with Janus kinase inhibitors 1. These molecules are released by various cells, including immune cells like macrophages and mast cells, in response to tissue damage or infection. The key inflammatory mediators include:

  • Cytokines, such as tumor necrosis factor (TNF)-inhibitors, which have been shown to be effective across a broad range of immune-mediated inflammatory diseases (IMIDs) 1
  • Chemokines, which attract immune cells to the site of inflammation
  • Prostaglandins and leukotrienes, which are involved in the regulation of blood vessel dilation and permeability
  • Histamine and bradykinin, which contribute to increased vascular permeability and smooth muscle contraction
  • Complement proteins, which help to eliminate pathogens from the body
  • Reactive oxygen species, which can directly damage pathogens but also contribute to tissue damage if produced in excess.

The regulation of these inflammatory mediators is critical, as dysregulation can lead to chronic inflammatory diseases, such as rheumatoid arthritis, psoriatic arthritis, and inflammatory bowel disease, as discussed in the context of Janus kinase inhibitors 1. Understanding the specific roles of these mediators is essential for the development of targeted therapies that can modulate the inflammatory response while minimizing side effects.

From the FDA Drug Label

The FDA drug label does not answer the question.

From the Research

Definition of Inflammatory Mediators

Inflammatory mediators are a group of molecules that play a major role in inflammatory processes. They can be divided into two main groups:

  • Prostaglandins (PG)
  • Cytokines 2

Types of Inflammatory Mediators

Some of the key inflammatory mediators include:

  • Prostaglandins: PGE2, PGD2, and PGI2, which are involved in cardiovascular and rheumatoid diseases 2
  • Cytokines:
    • Interleukins (IL): IL-1, IL-6, IL-10, IL-33 3, 4
    • Tumor necrosis factor-alpha (TNF-α) 3, 4
    • Interferons 2, 4
    • Transforming growth factor-beta (TGFβ) 2, 4
  • Small-molecule inflammatory mediators:
    • Leukotrienes
    • Reactive oxygen species
    • Nitric oxide
    • Lipoxins
    • Platelet-activating factor, which play a significant role in the development of rheumatoid arthritis 5

Role of Inflammatory Mediators

Inflammatory mediators can have both pro- and anti-inflammatory properties, and their balance is crucial for targeted therapeutic approaches 2. They can be used as biomarkers to indicate or monitor disease or its progress, and also may serve as clinically applicable parameters for therapies 3. However, their precise role is not always clearly defined 3.

Therapeutic Targets

Inflammatory mediators can be potential therapeutic targets, and many drugs targeting these mediators have demonstrated good efficacy in mouse models of rheumatoid arthritis 5. Blocking proinflammatory cytokines, such as IL-1 and TNF, has been highly successful in patients with rheumatoid arthritis, inflammatory bowel disease, or graft-vs-host disease 6.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Pro- and Anti-Inflammatory Prostaglandins and Cytokines in Humans: A Mini Review.

International journal of molecular sciences, 2023

Research

Cytokines in Inflammatory Disease.

International journal of molecular sciences, 2019

Research

Cytokines in acute and chronic inflammation.

Frontiers in bioscience : a journal and virtual library, 1997

Research

Proinflammatory cytokines.

Chest, 2000

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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