Allies or Enemies? The Power of Plant Hormones in Animals: Insights into Their Regulatory Roles

Abstract

Phytohormones, representing a diverse group of molecules, are essential in orchestrating plant growth and development, ensuring the smooth progression of the entire life cycle from germination to senescence. Emerging research reveals that these compounds also exert biological effects in non-plant systems, including animals. Although some phytohormones can be harmful, their health-promoting potential is rapidly gaining attention. This has sparked a growing interest in exploring plant hormones as novel therapeutic agents, particularly in precision medicine. This review brings together a multidisciplinary team-plant physiologists, a pharmacist, and a medical doctor-to delve into the latest insight surrounding the health-related impacts of plant hormones on animal systems, with a particular emphasis on human health. We comprehensively analyze their effects, weighing both the benefits and potential risks. Key phytohormones-auxin, abscisic acid, cytokinins, jasmonates, ethylene, strigolactones, and gibberellins-are highlighted for their remarkable regulatory roles in animal physiology, with a special focus on their implications for human health. Our discussion reveals how phytohormones may help address critical health challenges, particularly those related to aging populations, including neurodegenerative diseases, diabetes, and cancers. These plant-derived molecules are emerging as promising candidates for future drug development and nutritional therapies. Hence, a deeper understanding of phytohormone action may not just revolutionize agriculture but also open new frontiers in medicine and human health.

Keywords: auxin; cancer; cytokinins; ethylene; jasmonates; phytohormones; plant hormones.

Figure 1

The chemical structures of the selected natural and synthetic phytohormones active in animal tissues. The structures were obtained from www.chemspider.com. For more details, see the text.

Figure 2

Diversity of beneficial activities of plant hormones toward human disease and disorders. Abbreviations: ABA—abscisic acid, CYT—cytokinin, ET—ethylene, GA-13315—13-chlorine-3,15-dioxy-gibberellic acid methyl ester, IAA—indole-3-acetic acid, IAA-HRP—indole-3-acetic acid/horseradish peroxidase complex, JAs—jasmonates, LR2412—tetrahydrojasmonic acid (trade name), MeJA—methyl jasmonate, SL—strigolactone.