Naturally occurring polyphenolic antioxidants modulate IgE-mediated mast cell activation

Area of Science:

• Immunology
• Cell Biology
• Pharmacology

Background:

• Reactive oxygen species (ROS) significantly influence cellular signaling pathways, including kinase, phosphatase, and transcription factor activities.
• Rutin and chlorogenic acid (CGA) are key polyphenolic antioxidants found in smokeless tobacco leaf extracts.
• Mast cells play a crucial role in allergic responses, releasing histamine and cytokines upon activation.

Purpose of the Study:

• To investigate the effects of rutin and CGA on reactive oxygen species (ROS) production in mast cells.
• To determine the impact of rutin and CGA on histamine release and cytokine production in activated mast cells.
• To explore the potential of these tobacco polyphenols in modulating IgE-mediated allergic reactions.

Main Methods:

• Quantification of intracellular ROS using fluorescence-activated cell sorting (FACS) with carboxy-dichlorofluorescein (DCFH-DA).
• Measurement of histamine release from IgE-sensitized murine mast cells following antigen challenge.
• Analysis of inducible cytokine messenger levels (IL-10, IL-13, IFN-gamma, IL-6, TNF-alpha) using quantitative methods.

Main Results:

• Antigenic challenge of IgE-sensitized mast cells significantly increased intracellular ROS levels.
• Rutin and CGA treatment effectively reduced ROS levels and histamine release in activated mast cells.
• Conversely, rutin and CGA enhanced the expression of inducible cytokines, including IL-10, IL-13, IFN-gamma, IL-6, and TNF-alpha.

Conclusions:

• Tobacco-derived polyphenols, rutin and CGA, differentially modulate effector functions of mast cells.
• These antioxidants quench intracellular ROS, inhibit histamine release, yet augment cytokine production in activated mast cells.
• The net effect of these polyphenols on IgE-mediated allergy in vivo is dependent on the balance of their dual effects on mast cell activation, highlighting a potential therapeutic target.