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Effort and Laziness
Published in Robert S. Holzman, Anesthesia and the Classics, 2022
Hormesis, as a biological process, is characterized by a biphasic response to exposure to increasing amounts of a substance or condition. Within the hormetic zone, there is generally a favorable biological response to low exposures to toxins and other stressors.
Lifestyle and Diet
Published in Chuong Pham-Huy, Bruno Pham Huy, Food and Lifestyle in Health and Disease, 2022
Chuong Pham-Huy, Bruno Pham Huy
The mechanisms of the Mediterranean diet’s effects on health are still unclear. However, some authors have suggested that many components in foods of this diet exert the hormetic effects (223). Hormesis is a term used by toxicologists to refer to a biphasic dose response or an inverted U-shaped dose response to an environmental agent characterized by a low dose stimulation or beneficial effect and a high dose inhibitory or toxic effect (224). For example, some essential micronutrients such as selenium, fluorine, and iodine, ingested at low doses through foods, are beneficial to the body; in contrast, when they are taken at high doses, they become toxic. In the fields of biology and medicine, hormesis is defined as an adaptive response of cells and organisms to a moderate or intermittent stress (224).
Hormesis
Published in T. D. Luckey, Radiation Hormesis, 2020
Hormology is the study of excitation. Hormesis is the stimulation of any system by small amounts of any agent. Large amounts of the same agent slow or stop the system, whether it is a physical, chemical, or biologic system. Radiation hormesis in biology is the stimulation of physiologic functions evoked by exposure to low doses of ionizing radiation.
The pros and cons of motor, memory, and emotion-related behavioral tests in the mouse traumatic brain injury model
Published in Neurological Research, 2022
Ruoyu Zhang, Junming Wang, Leo Huang, Tom J. Wang, Yinrou Huang, Zefu Li, Jinxin He, Chen Sun, Jing Wang, Xuemei Chen, Jian Wang
Preconditioning is a manifestation of hormesis which is defined as a noxious stimulus below the cell injury threshold that can lead to cellular protection from subsequent severe insult [152,153]. Neuroprotection conferred by preconditioning has been demonstrated in several preclinical TBI studies with promising results [154]. The behavioral tests can be used as parameters to reflect the functional outcomes of hormesis in these experimental conditions. As one of the important preconditioning signals, sublethal doses of N-methyl-d-aspartate (NMDA) can induce endogenous protective mechanisms, which improves functional recovery after TBI. In the study by Costa et al., the NMDA preconditioning before TBI led to improvement in sensory-motor activity, coordination, and balance without distortion of gait [155]. Moojen et al. showed that the mice under NMDA preconditioning were protected against TBI-induced cognitive deficits evaluated by the novel object recognition test [156]. Additionally, endotoxin lipopolysaccharide preconditioning attenuated TBI-induced motor deficits assessed by NSS and the beam walking test [157]. Therefore, evaluation of behavioral correlates of histologically measured gray and white matter injury can help elucidate endogenous protective and repair mechanisms of preconditioning signals.
The Subtle Role of Para-inflammation in Modulating the Progression of Dry Eye Disease
Published in Ocular Immunology and Inflammation, 2021
Maurizio Rolando, Stefano Barabino
The term hormesis is mostly used by toxicologists to describe a biphasic dose−response reaction, characterized by a low-dose stimulation or beneficial effect vs. a high-dose inhibitory or toxic effect.12 The same concept is used in biology and medicine to define an adaptive compensatory response of a cell or organism to a moderate (usually intermittent) stress or toxic stimulus that causes an initial disruption in homeostasis. As long as the stress or damage is limited, the loss of homeostasis can be compensated by activating the hormetic response for a definite period of time. Conversely, if the damaging stimulus is persistent or stronger, the overcompensation can induce a toxic inflammatory process, which has been linked to the protraction of multiple diseases.13
Bi-phasic dose response in the preclinical and clinical developments of sigma-1 receptor ligands for the treatment of neurodegenerative disorders
Published in Expert Opinion on Drug Discovery, 2021
Bi-phasic (bell-shaped) dose-response effects were originally introduced through the notion of hormesis, and particularly discussed by Calabrese [for reviews and main contributions, see [89–92]. Hormesis is defined as a paradoxical beneficial effect seen with low doses and less beneficial effect at higher doses. Applied to the S1R chaperone protein, hormesis corresponds to the bi-phasic effect observed in specific as well as more integrated physiological or behavioral responses. We will now detail the numerous observations showing that S1R agonists respond to the definition of bi-phasic effects in pre-clinical, in vitro or in vivo models, as well as in clinical trials. Almost no contrary data have been reported when drugs are tested in a sufficiently wide dose-range, thus indicating that hormesis is likely an intrinsic characteristic of S1R activity. Some typical examples are presented in Figure 2.