Leukotriene C₄ (LTC₄)

Class Eicosanoid / cysteinyl leukotrieneReceptor CysLT₁ and CysLT₂ receptors

Function

Leukotriene C4 is a lipid-derived inflammatory hormone involved in bronchial smooth muscle contraction, vascular permeability regulation, mucosal signaling, and inflammatory communication. LTC4 belongs to the cysteinyl leukotriene family and plays major roles in respiratory physiology and allergic inflammatory responses.

The hormone promotes bronchoconstriction, airway edema, mucus secretion, and vascular permeability changes within respiratory tissues. LTC4 also influences eosinophil recruitment, endothelial signaling, and smooth muscle responsiveness. Through these actions, it contributes to coordination of inflammatory responses within airway and mucosal environments.

Production

LTC4 is synthesized from arachidonic acid through the lipoxygenase pathway within activated immune cells. Five-lipoxygenase converts arachidonic acid into leukotriene A4 intermediates, which are then conjugated with glutathione through LTC4 synthase activity to form leukotriene C4.

Production occurs mainly in mast cells, eosinophils, basophils, macrophages, and additional inflammatory cell populations. Synthesis increases rapidly during allergen exposure, immune activation, oxidative stress, and inflammatory signaling. Because LTC4 is produced locally and acts quickly, its biological effects remain largely tissue-specific.

Regulation

LTC4 production is regulated by immune receptor activation, inflammatory cytokines, phospholipase signaling pathways, calcium mobilization, oxidative stress, and mast-cell activation. Leukotriene synthesis pathways are closely integrated with inflammatory signaling networks and respiratory immune responses.

LTC4 acts mainly through cysteinyl leukotriene receptors located on airway smooth muscle, vascular tissue, inflammatory cells, and mucosal tissues. Receptor activation stimulates calcium signaling, smooth muscle contraction, vascular permeability changes, and mucus secretion pathways. Through these integrated lipid-signaling systems, LTC4 coordinates bronchial responsiveness, inflammatory adaptation, vascular signaling, and mucosal immune communication during respiratory and allergic inflammatory states.

Identity & Secretion

Primary Source GlandLeukocytes (mast cells, eosinophils, basophils, macrophages)
Secretion PatternProduced during immune activation upon cell injury or pathogen-associated signaling
PrecursorArachidonic acid → LTA₄ → LTC₄

Nutrient Requirements

Nutrient Precursors
  • Linoleic acid → Arachidonic acid; ALA → EPA (competes for lipid mediator pathway)
Required Vitamins
  • Vitamin C (redox buffering), Vitamin B3 (NAD/NADP), Vitamin B6 (amino acid metabolism context)
Required Minerals
  • Magnesium (smooth muscle regulation), Selenium (glutathione recycling), Iron (enzyme systems)

Key Foods

  • Flaxseed, chia, walnuts, leafy greens, turmeric, ginger, berries, green tea (contextual polyphenol modulation)

Targets & Signaling

Target Tissues
  • Smooth muscle, vascular endothelium, epithelial lining cells
Feedback Loops
  • Autocrine and paracrine loops with cytokines and prostaglandins (context only)
Second Messengers
  • IP₃/Ca²⁺ signaling cascade (Gq-linked)
Pathways Involved
  • PLA₂ → ALOX5 → LTA₄ → LTC₄; CysLT receptor signaling via Gq pathways

Key Functions

  • Promotes smooth muscle contraction, vascular permeability, and mucus production during inflammatory signaling.

Plant-Based Focus

  • Whole plant foods rich in ALA, EPA precursors, and polyphenols may help support balanced eicosanoid profiles (context only).

Clinical Context

Assay Notes
Urinary LTE₄ is commonly used as a downstream index metabolite; depends on sample timing and inflammation state.

Linked Knowledge

Phytochemicals
  • Curcumin, quercetin, resveratrol, EGCG, baicalein, hesperidin (reported pathway modulators in research models)
Foods
  • Flaxseed, chia, walnuts, leafy greens, legumes, turmeric, ginger, berries
Vitamins
  • Vitamin C, Vitamin B3, Vitamin B6
Minerals
  • Magnesium, Selenium, Iron
Cancers (context)
  • Discussed in tumor microenvironment immunology literature (context only, not diagnostic).
Ailments
  • Discussed in airway, vascular, and inflammatory biology contexts (informational, not medical).

Dietary Modulators

  • Whole-food diet patterns may support balanced inflammatory lipid mediator synthesis (context only).

Inhibitors / Activators

Inhibitors
  • Pro-inflammatory cytokine activation and oxidative stress signaling (context only).
Activators
  • Exercise and improvement of metabolic-redox environment may shift leukotriene tone (context only).

Summary

LTC₄ is a lipid signaling molecule that modulates vascular tone and inflammatory tissue response.

SUMMARY OF EFFECTS ON THE BODY

Context-only: Plant-based dietary patterns rich in polyphenols and ALA may support balanced eicosanoid signaling.

Research

PMID: 30254261; PMID: 34021071; PMID: 32647152
Created: Nov 11, 2025 Updated: May 27, 2026