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wrote...
Valued Member
Educator
4 years ago Edited: 4 years ago, bio_man
Do you find any related reference on how sunlight keep SERT levels low based on  biological processes?

SERT concentration and sunlight are *not* related. There's no literature that makes this correlation either. There is a correlation, however, between seasonal variations and SERT gene expression, where those with SAD had higher SERT concentrations. We can't blame the lack of sun, for example, for SAD, and for the same reason blame the lack of sun for high SERT concentrations because there isn't a direct biological reason connecting the two variables.
oemBiology Author
wrote...
4 years ago Edited: 4 years ago, oem7110
"Serotonin levels. A drop in serotonin, a brain chemical (neurotransmitter) that affects mood, might play a role in SAD. Reduced sunlight can cause a drop in serotonin that may trigger depression."

Referring to above statement, it seems that SERT is not the right direction, Redcing sunlight would drop serotonin instead of activating SERT.

"Serotonin, normal seasonal variations, and sunlight. According to the empirical literature, there appears to be a relationship between normal seasonal variations in the levels of serotonin and the amount of available sunshine. At the very basic science level, exposure to light has been reported to activate the synthesis of serotonin in yeast extracts, suggesting a direct relationship between sunshine and the production of serotonin."

REF : https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3779905/

I would like to know on what spectrum (color / wavelength) of light would help to grow yeast faster.

Do you have any suggestions?
Thank you very much for any suggestions (^v^)
wrote...
Valued Member
Educator
4 years ago
You're right. I did not know sunlight affects serotonin levels, this is new to me.

I found an excellent article that should answer all your questions. I've uploaded it below:

In this article, it mentions this part which is important to you:

Serotonin, normal seasonal variations, and sunlight. According to the empirical literature, there appears to be a relationship between normal seasonal variations in the levels of serotonin and the amount of available sunshine. At the very basic science level, exposure to light has been reported to activate the synthesis of serotonin in yeast extracts, suggesting a direct relationship between sunshine and the production of serotonin.15 Available data also suggest that serotonin exhibits some customary or natural seasonal variation in the central nervous systems of normal human adults. For example, seasonal variations have been reported in platelet serotonin uptake and paroxetine binding, hypothalamic concentrations, plasma levels, and concentrations of metabolites in the cerebral spinal fluid as well as with neuroendocrine challenges with serotonin antagonists.16 In addition, light has been reported to influence the binding of serotonin at the serotonin 1A receptor site, with lower light levels associated with lower binding levels in the cortical and subcortical limbic regions of the brain.17 Serotonin transporters have also demonstrated binding potentials that vary in normal humans throughout the year—a finding that was statistically related to the average duration of daily sunshine.18 In direct support of customary seasonal variations in serotonin, Lambert et al19 sampled jugular blood from 101 healthy male volunteers, one sample each during 12 months, and determined that serotonin levels were lowest in the winter.19

While there have been some inconsistencies among these studies (e.g., a lack of seasonal variation in serotonin transporters has been reported),20,21 they collectively suggest that normal adults tend to exhibit elevated serotonin levels in the late summer and fall, and reduced serotonin levels in the spring—likely in relationship to available sunlight. Given these normal variations, it may be that individuals who are susceptible to seasonal effects are especially sensitive to these changes in the presence of psychopathology.

Serotonin and the skin. In addition to other body sites (e.g., brain, gut, platelets), serotonin is present in human cutaneous tissue. This conclusion is founded upon the discovery that the machinery of the serotonergic system is present in the skin. For example, tryptophan hydroxylase, the initial enzyme in the synthesis of serotonin, is found in human skin.14 Likewise, serotonin and serotonin transporters have been detected in human keratinocytes, the predominant cell type (90%) in the epidermis. This leads to the deduction that mammalian skin can actually produce serotonin.14 Stated in scientific prose, Slominski et al22 posit that human skin expresses intrinsic serotonin biosynthetic pathways. Slominski et al also point out the common embryological ectodermal origin of the brain and the epidermis, which supports the presence in both of similar biological elements. These researchers even suggest that the cutaneous serotonergic system may be the evolutionary remnant of an ancestral system that operated primarily in the periphery.14

Skin and light—an explanation for seasonal variation? While there are other contributing explanations for the relationship between light and serotonin, such as the retinoraphe tract23 (i.e., a tract between the retina and raphe nuclei that might account for the light-induced modulation of serotonin), the role of the skin in the generation of serotonin remains a competing possibility. In support of the role of the skin in the photostimulation of serotonin, Gambichler et al24 conducted an intriguing study. These investigators examined the effects of light exposure in the laboratory for three weeks on 42 subjects in comparison with 11 controls. All participants wore opaque goggles, which for those exposed to light were designed to block out ultraviolet-A radiation (i.e., to eliminate the retinal mediation of serotonin effects). Individuals exposed to light evidenced higher serum serotonin levels during this experiment than controls, which the authors proffered might be explained by a “cutaneous pathway.”

While the preceding data are preliminary, findings suggest that the seasonal alterations in serotonin may partially be the result of the serotonin infrastructure in the skin. In other words, it is possible that the skin, itself, is involved in the production and bio-regulation of serotonin. (This phenomenon might partially explain the human predilection for sunbathing.) This is not meant to exclude other pathways such as the retinoraphe tract.

Hope this helps and apologies for the confusion on my previous post. Smiling Face with Halo
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oemBiology Author
wrote...
4 years ago
I would like to know on what spectrum (color / wavelength) of light would help to grow yeast faster.

Do you have any suggestions?
Thank you very much for any suggestions (^v^)
wrote...
Valued Member
Educator
4 years ago
https://www.ncbi.nlm.nih.gov/m/pubmed/2786220/

337 nm

But remember, yeast are never used as a model for animals, so do not base your understanding off of that.
oemBiology Author
wrote...
4 years ago
Conclusion : exposure to light Near-UV (337 nm) has been reported to activate the synthesis of serotonin in yeast extracts, that would solve the winter blue issue, right?

Thank you very much for suggestions (^v^)
wrote...
Valued Member
Educator
4 years ago
Conclusion : exposure to light Near-UV (337 nm) has been reported to activate the synthesis of serotonin in yeast extracts, that would solve the winter blue issue, right? Thank you very much for suggestions (^v^)

Definitely not the case for humans, not even close. As mentioned:

Quote
yeast are never used as a model for animals, so do not base your understanding off of that.
oemBiology Author
wrote...
4 years ago
This conclusion is founded upon the discovery that the machinery of the serotonergic system is present in the skin. For example, tryptophan hydroxylase, the initial enzyme in the synthesis of serotonin, is found in human skin

Should enzyme activate the synthesis of serotonin instead of yeast?
If yes, I would like to know on what spectrum (color / wavelength) of light would help to grow enzyme faster.

Do you have any suggestions?
Thank you very much for any suggestions (^v^)
wrote...
Valued Member
Educator
4 years ago
Should enzyme activate the synthesis of serotonin instead of yeast?

Ignore the yeast finding. It doesn't pertain to humans. Yes, enzymes are what's responsible for the biosynthesis of serotonin in yeast, but who cares? You're concerned about SAD -- a condition related to humans.

would like to know on what spectrum (color / wavelength) of light would help to grow enzyme faster.

Everything minus ultraviolet.
oemBiology Author
wrote...
4 years ago
I would like to know on whether blue or red light help to accelerate chemical reactions within enzyme faster.

Do you have any suggestions?
Thank you very much for any suggestions (^v^)
wrote...
Valued Member
Educator
4 years ago
I looked up the actual study referenced above. It was called

Impact of UVA exposure on psychological parameters and circulating serotonin and melatonin

According to the study, the subjects were exposed to UVA, which has a wavelength between 315–400 nm.

Quote
I would like to know on whether blue or red light help to accelerate chemical reactions within enzyme faster.

The same study mentions:

We found a modest increase of serotonin and a decrease of melatonin levels in the UVA-exposed volunteers at T2. Both changes were statistically significant (P < 0.001; P < 0.01). At all times, differences of serotonin levels of the non-exposed controls did not reach significant levels. The conversion of serotonin to melatonin is a photosensitive step resulting from the photoinhibition of the enzymes N-acetyltransferase. It has recently been reported that UVA radiation is a powerful signal affecting the pineal melatonin-generating system and inhibits N-acetyltransferase [33,38,39]. Accordingly, it has been observed that melanocytes are photoresponsive cells which express and metabolize indolamines, such as melatonin, during the G2 phase while responding to UV exposure [40]. Therefore, we make the hypothesis that UVA radiation leads to an inhibition of N-acetyltransferase via a cutaneous pathway [41]. As a result the production of serotonin increases at the expense of melatonin.
oemBiology Author
wrote...
4 years ago Edited: 4 years ago, oem7110
After UVA exposure, is there information mentioned about how long this chemical effect lasts for increasing the production of serotonin at the expense of melatonin?

For example, UV today is 7 (High) and I go to take a Sunbath for 2 hours on the beach, how long period is last for increasing the production of serotonin at the expense of melatonin within my body?

Do you have any suggestions?
Thank you very much for any suggestions (^v^)



Post Merge: 4 years ago

"The sun's rays provide warmth and light that enhance your general feeling of well-being and stimulate blood circulation. Some UV radiation is essential to the body as it stimulates the production of vitamin D. Vitamin D has an important function in increasing calcium and phosphorus absorption from food and plays a crucial role in skeletal development, immune function and blood cell formation. There is no doubt that a little sunlight is good for you! But 5 to 15 minutes of casual sun exposure of hands, face and arms two to three times a week during the summer months is sufficient to keep your vitamin D levels high. Closer to the equator, where UV levels are higher, even shorter periods of exposure suffice."

https://www.who.int/uv/faq/uvhealtfac/en/index1.html

Referring to above statement, after 15 minutes of sun exposure, vitamin D is generated within body, I would like to know on how long this dosage of vitamin D last based on body's daily consumption.

Do you have any suggestions?
Thank you very much for any suggestions (^v^)

Post Merge: 4 years ago

"Another study found that 30 minutes of midday summer sun exposure in Oslo, Norway was equivalent to consuming 10,000–20,000 IU of vitamin D (8).

The commonly recommended daily dose of vitamin D is 600 IU (15 mcg) (3)."

https://health.usnews.com/wellness/articles/2018-07-18/how-much-time-in-the-sun-do-you-need-for-vitamin-d

Based on above statement, for 30 minutes sun exposure, it generates 15,000 IU of vitamin D, which equal to 25 days dose.

so for 30 minutes sun exposure, during winter, I would like to know on how long period is last for increasing the production of serotonin at the expense of melatonin within my body?
Post Merge: 4 years ago

"Rohan and her team followed up with people the next two winters. The CBT folks were done with treatment after the initial winter, but the light-therapy subjects would have to keep it up.

In winters one and two, both groups had similar reductions in SAD symptoms. But there was a marked difference in the third winter: People who did light therapy had a relapse rate of 46 percent versus 27 percent in the CBT group, and they had more severe symptoms, too.

Why? Because they stopped doing it. People had to return the boxes to the lab after the first winter for upkeep, like bulb replacement. Before winter two, they got letters saying they could come in to borrow a box, and listing specifications if they preferred to buy one. For winter three, the lab didn’t offer loaners, but Rohan did offer to write letters to people’s insurance companies arguing that they should be covered. Less than a third of subjects in this group reported any light therapy that winter. And thus the higher relapse rate."

https://www.thecut.com/2016/01/sad-lamp-light-therapy-for-seasonal-depression.html

Referring to above statement, I don't understand why people who did light therapy had a relapse rate of 46 percent versus 27 percent in the CBT group, and they had more severe symptoms, too.

Do you have any suggestions on what is going on after light therapy?
Thank you very much for any suggestions (^v^)

Post Merge: 4 years ago

Starting 0:50, "The life-sustaining power of enzymes lies in the fact that they catalyze reaction in mild conditions of pH, temperature and atmospheric pressure"


Referring to above statement, I would like to know on how following factors affect enzymes' efficiency on catalyze reaction:
1) pH
2) temperature
3) atmospheric pressure

Do you find any related reference on this issue?
Thank you very much for any suggestions (^v^)

Post Merge: 4 years ago

The optimum factors are different based on different enzymes, for winter blue - moods, I would like to know on what optimum factors are for those enzymes related to moods' issues.






wrote...
Valued Member
Educator
4 years ago Edited: 4 years ago, bio_man
Quote
After UVA exposure, is there information mentioned about how long this chemical effect lasts for increasing the production of serotonin at the expense of melatonin? For example, UV today is 7 (High) and I go to take a Sunbath for 2 hours on the beach, how long period is last for increasing the production of serotonin at the expense of melatonin within my body? Do you have any suggestions? Thank you very much for any suggestions (^v^)

According to the study, subjects were separated into two groups based on their skin type:

  • skin type II: 15 min.
  • skin type III: 20 min.

These types were based on the Fitzpatrick's classification (best to read the article to understand this further).

Source: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC113771/

- - -

Given that our discussion here is based on SAD, serotonin, etc., best to start a new topic on the other inquiries you have. We're not staying on topic Grinning Face with Smiling Eyes
oemBiology Author
wrote...
4 years ago
Thank you very much for suggestions (^v^)
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