Bacteriostatic Potential of Melatonin: Therapeutic Standing and Mechanistic Insights

Area of Science:

• Microbiology
• Immunology
• Plant Pathology

Background:

• Bacterial diseases in animals and plants cause significant mortality and economic losses.
• Melatonin, a naturally occurring molecule, exhibits diverse biological functions.
• Emerging evidence suggests melatonin's potential role in combating bacterial infections.

Purpose of the Study:

• To review the antibacterial effects of melatonin across various models.
• To elucidate the mechanisms underlying melatonin's protective actions against bacterial pathogens.
• To assess the potential of melatonin as a therapeutic agent for bacterial infections.

Main Methods:

• Literature review of studies investigating melatonin's antibacterial properties.
• Analysis of in vitro, animal, and plant-based experimental data.
• Examination of signaling pathways and molecular mechanisms involved in melatonin's action.

Main Results:

• Melatonin demonstrates broad-spectrum antibacterial activity against Gram-negative, Gram-positive, and other bacteria, including Mycobacterium tuberculosis.
• Indirect mechanisms, such as immune system activation and anti-inflammatory effects, are key to melatonin's protective role.
• In plants, melatonin modulates the mitogen-activated protein kinase (MAPK) pathway; in animals, it influences pathways like NF-κB, STAT-1, Nrf2, NLRP3 inflammasome, MAPK, and TLR-2/4.
• Melatonin reduces reactive oxygen and nitrogen species (ROS, RNS), aids detoxification, and protects mitochondria.

Conclusions:

• Melatonin exhibits significant antibacterial potential through direct and indirect mechanisms.
• Its ability to modulate host defense and inflammatory responses is crucial for combating bacterial infections.
• Melatonin represents a promising therapeutic strategy for managing bacterial diseases in both animals and plants.