Archives - Biology: Page 22
Author: paul carson (Wed Mar 29, 2006 2:55 am)
Title: BIOLOGY
Genes that control an organism’s ability to withstand adversity cause changes throughout the body that render it temporarily supercharged for survival. Activated over the long term, this stress response prolongs life span and forestalls disease in a wide range of organisms.
Sirtuins are a family of genes that maybe master regulators of this survival mechanism. Understanding how they produce their health and longevity enhancing effects could lead to disease treatments and ultimately longer, disease free human life spans.
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grow and be kind
I've never heard any medical evidence to support that increased levels of stress would increase longevity. As far as I know, stress is detrimental to our health. When we experience stressful situations, our pituitary gland releases high levels of adrenocorticotropic hormone, known as ACTH. This release triggers additional hormonal releases in our body like adrenaline. These hormones boost concentration, reaction time, agility, aggressiveness, etc. While these reactions are beneficial in fight or flight situations for short term advantages, they pose no benefit in the long term.
Sirtuins are seen as a universal regulator of aging, yes, but they are not a "stress response." They are always present in the cells, and when stress occurs within a particular cell, sirtuins are able to minimize its effects. They are especially potent when the stress is due to a lack of food. It is also important to note that sirtuins are believed to aid in mainly geriatric diseases, such as Alzheimer's Disease.
Scientists' knowledge of the aging process is limited at best, and we should not put too much faith in any one "miracle solution." The laboratory testing of sirtuins is only in the elementary stages, and until they have moved on to testing higher life forms, the effects on humans cannot be postulated.
In 1962 Schachter and Singer published an article in Psychology Review presenting their cognitive theory of emotions based on a famous and controversial experiment. Their theory stated that in order to have an emotion, cognitive and physiological components were needed. Schachter and Singer emphasized that both the cognitive interpretation and labeling, as well as the physiological component(triggered by the cognitive perceptive mechanism) were needed in order to complete the processes necessary for an emotion to occur.
More recent research on emotions include the physiological response as a necessary part of the process. The physiological response is also the engine of the fight or flight response.
Perhaps aggression and fear are among the best known emotions that we know. The stress response share the same physiological mechanisms that are also part of emotions.
Some of the neurotransmitters and hormones related to the stress response are the following:
Cortex
Serotonin
Norepinephrine
Acetylcholine
Hypothalamus
Corticotropin releasing factor
Somatostatin
Dopamine
Arginine vasopressin
Pituitary
ACTH
Beta endorphin
Growth hormone
Prolactin
Adrenal
Coticosteroid
Norepinephrine
Epinephrine
Enkephalin
Sympathetic Division of the ANS
The stress response communicates with the immune system. Stress compromises the immune response; in deed both system communicate and help regulate each others performance. The brain and the immune system interact via hormones, neurotransmitters, and cytokines traveling through blood and nerves. This bi-directional chemical communication is regulated by corticotropin releasing factor, which is stimulated by thoughts and emotions or immune activation to affect the hypothalamic-pituitary-adrenal axis. Stress, in particular, compromises immunity. Stressful life events have been linked with susceptibility to infection, reactivation of herpesvirus, and with cancer and HIV progression.
When we mentioned sirtuins(genes) that encodes a protein(enzyme in this case) as a stress vector we didn’t mean to equate it to what we consider the “stress response” related to emotions. We meant that sirtuins activate the stress specific response that prolongs span and delays diseases in a life organism. In mammalians an enzyme known as SIRT1( produced by the SIRT1 gene) which among other things have an effect on proteins that control very important process (apoptosis included) help trigger the stress response in mammalian’s cells. This response seem to be responsible for health and longevity enhancing the effects of caloric restrictions in mammals. Sirt1 may also coordinate the same stress response throughout the body.
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grow and be kind