The Xenohormesis hypothesis, ..

Although there is considerable validity to this theory, there is accumulating evidence that this may not be the entire story. There are abundant examples of interactions between plant and animal molecules that cannot be readily explained by the “common origin” hypothesis. For example, why do some plant signaling molecules interact directly with animal enzymes and promote health despite having no apparent homolog or chemical relative in animals? One could argue that these molecular interactions are simply a fortuitous coincidence, with the vast majority of plant molecules being either toxic or producing no benefit to animals. Indeed, given the immensity of the chemical space occupied by plant secondary metabolites, such a view seems plausible. However, several factors suggest that selection, rather than mere coincidence, may be at work. Let us examine, as an example, members of one broad chemical class in plant foodstuffs that confer human health benefits: the polyphenols. The synthesis of polyphenols (and many other phytochemicals) is induced in plants by a variety of environmental stresses. Polyphenol content provides a chemical signature of the state of the environment. This chemical cocktail, when ingested, comes into intimate contact with the receptors and enzymes within the consumer. The fact that stress-induced plant compounds tend to upregulate pathways that provide stress resistance in animals suggests that plant consumers may have mechanisms to perceive these chemical cues and react to them in ways that are beneficial. We have coined the term xenohormesis to explain this phenomenon (from xenos, the Greek word for stranger, and hormesis, the term for health benefits provided by mild biological stress, such as cellular damage or a lack of nutrition).

but it's in accordance with the xenohormesis hypothesis.

as predicted by the xenohormesis hypothesis 6, 44, remains to be determined.
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Adrenal Fatigue: The 21st Century Stress Syndrome…

The Xenohormesis hypothesis, which is a central item in these dissertations, mentions that changes in the lifespan of an organism can occur due to stress-inducible molecules from an other organism (for example secondary metabolites in plants).


Following hypothesis build up the centre stage of our work approach:

1. Xenohormesis: phytoalexine produced by plants can cause hormesis in the nematode

One explanation for this surprising observation is the 'xenohormesis hypothesis', ..
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health”—a theory called xenohormesis

One explanation for this surprising observation is the ‘xenohormesis hypothesis’, the idea that organisms have evolved to respond to stress signalling molecules produced by other species in their environment.

Unlike mammals, yeast do not synthesize bile acids

Do plants under stress produce similar survival responses? And if so, do they produce chemicals or molecules that could be passed on to animals and humans? This is known as the Xenohormesis Hypothesis. The answer is yes and yes. More specifically, the Xenohormesis Hypothesis states “organisms have evolved to pick up on stress-signaling molecules from other species in their environment because it allows them to shift into a survival mode in advance of an environmental decline (Sinclair’s paper).”

Small molecules that regulate lifespan: evidence for xenohormesis.

It should be possible to test the xenohormesis hypothesis at the level of whole organisms and their ecology. For example, a testable prediction of xenohormesis is that stressing a plant such as Arabidopsis with heat or light would lengthen the life span of insects, such as aphids, that feed on it. The life span of aphids feeding on the leaves of the herb Shepherd’s Purse (Capsella bursapastoris) is known to be extended when the plant is water-stressed due to root predation by beetle larvae (). The greatest difficulty with such experiments may lie in designing sufficient controls to allow for an unambiguous interpretation. For example, one must be sure to distinguish xenohormetic lifespan effects from those that might arise from simple caloric restriction or lower levels of a particular nutrient or toxin. The genetic manipulations that are possible in Arabidopsis in the realm of polyphenol biogenesis may prove especially useful in this regard.