This changed my understanding of Vitamin D3 synthesis

[Jevin]

I still have the D3 on hand and a solameter, finally, but I also get bloodwork done about every six months to make sure everything is alright. At most I use Calcium with low D3 once a month. I limit the use as it caused calcium deposits in soft tissue. And from past experience, vitamin D is something the body struggles with dealing with an artificial source as it more closely resembles a hormone than vitamin as most animals produce what is needed by synthesis in a certain layer of the dermis. And vitamin D is synthesized by the dermis, and metabolized by the liver into D3, if I remember correctly from the biology courses I've taken in university. Does any one know what effects supplementing vitamin D in chams does compared to D3?

Edit : I should clarify the precursor to different forms of vitamin D, rather than forms of Vitamin D for supplementation. I went and reread a bit of my textbook as I thought something was off.

 

[kinyonga]

@Jevin said..."Does any one know what effects supplementing vitamin D in chams does compared to D3?"...please clarify what you mean.

 

[Jevin]

I'm referring to the precursor for D3 in particular, which in the body is oxidized into the usable form of D3 immediately, if I remember correctly. The supplementation I would be referring to would be 7-dehydrocholesterol. Not sure if it can be supplemented though as it is synthesized from a protein coded for in DNA. This is why vitamin D is considered to be closer to a hormone than a vitamin as most living creatures obtain it through biosynthesis, not diet.

 

[kinyonga]

I know that vitamin D is considered a hormone at times.

D3 from supplements is ready to go to work...it's past the point of being able to be converted back into pre D3 as far as I understand and thus can lead to an overdose. D3 derived from exposure to the UVB light is generally not able to lead to an overdose ever, since it is buffered while still in the skin....so it should be safe. Not sure this answers your question or not.

 

[Jevin]

I know that vitamin D is considered a hormone at times.

D3 from supplements is ready to go to work...it's past the point of being able to be converted back into pre D3 as far as I understand and thus can lead to an overdose. D3 derived from exposure to the UVB light is generally not able to lead to an overdose ever, since it is buffered while still in the skin....so it should be safe. Not sure this answers your question or not.

Clarifies it, with what I've learned in biology classes, I tend to let nature do it's thing as it's had millions of years of evolution to get to this point, so humanities understanding and ability to change it for the better is limited in a certain way.

 

[DocZ]

I'm referring to the precursor for D3 in particular, which in the body is oxidized into the usable form of D3 immediately, if I remember correctly. The supplementation I would be referring to would be 7-dehydrocholesterol. Not sure if it can be supplemented though as it is synthesized from a protein coded for in DNA. This is why vitamin D is considered to be closer to a hormone than a vitamin as most living creatures obtain it through biosynthesis, not diet.

The supplements seem to all have cholecalciferol. This is the product that is carried away from the skin by vitamin D binding protein after photo and thermo isomerization of 7-DHC and pre vitamin D respectively in the skin.
As you said it then is hydroxlated in the liver to calcidiol and then in the kidney to calcitriol which is the active form of D3. It causes lots of effects like calcium absorption in the gut, phosphate reabsorption in the kidneys, suppresses parathyroid hormone expression, and stimlulates osteoclasts to promote bone resorption.
I’m not sure how dietary 7-DHC would work since it is converted to cholecalciferol in the skin, not throughout the body

interesting that you saw soft tissue calcification. Was that picked up on X-rays?

 

[kinyonga]

From what I know about soft tissue calcification...doesn't it have to have excess vitamin D3 for it to happen...and that would be from a supplement I believe.

 

[kinyonga]

With the way the wave lengths and warmth of the daylight change throughout the day, should we be more concerned with finding a better way to produce a more normal/daylight/natural way of providing the lighting for the chameleon rather than worrying about the way we supplement the D3 now?

How much difference is there in the amount of D3 produced compared to the amount of melanin in the chameleon's skin?

 

[DocZ]

With the way the wave lengths and warmth of the daylight change throughout the day, should we be more concerned with finding a better way to produce a more normal/daylight/natural way of providing the lighting for the chameleon rather than worrying about the way we supplement the D3 now?

How much difference is there in the amount of D3 produced compared to the amount of melanin in the chameleon's skin?

I totally agree about finding ways to emulate natural daylight and temperature to encourage endogenous D3 synthesis over dietary supplementation

In humans, melanin levels affect D3 synthesis. It seems in reptiles it has to do with skin thickness of different layers of skin
http://www.uvguide.co.uk/skintests.htm

 

[kinyonga]

I've seen the UVguide report on the transmission through skin....and it does look that way...but I'd like to see a report on the same area in species that have constant dark coloration compar d to ones that are lighter....like compare the Namaqua chameleon to the Senegal for instance.

Maybe we will have to take that into consideration too when providing light for them?

 

[DocZ]

I've seen the UVguide report on the transmission through skin....and it does look that way...but I'd like to see a report on the same area in species that have constant dark coloration compar d to ones that are lighter....like compare the Namaqua chameleon to the Senegal for instance.

Maybe we will have to take that into consideration too when providing light for them?

I suspect you’re right that there would differences found dependIng on the Chams natural habitat. Namaqua Chams are a great example of one that probably has a thicker skin due to its habitat

 

[kinyonga]

The Antsingy leaf chameleon (B. Peramata) makes me wonder about the D3/skin transmission too.

 

[DocZ]

The Antsingy leaf chameleon (B. Peramata) makes me wonder about the D3/skin transmission too.

I wasn’t familiar with these. How very cool!
https://onlinelibrary.wiley.com/doi/10.1002/jmor.21135

 

[kinyonga]

They are very odd and not easy to keep either. I had a pair a long long time ago....before I knew enough to keep them properly...but it didn't help that they we're either.

 

[Tarzanfam]

Hey, since you guys are getting really into the science of this, I thought I would let you know that I joined a facebook group about reptile lighting and Frances Baines answered my question...herself! Crazy!!!!!!

 

[Klyde O'Scope]

Hey, since you guys are getting really into the science of this, I thought I would let you know that I joined a facebook group about reptile lighting and Frances Baines answered my question...herself! Crazy!!!!!!

Cool. I've had an exchange or 2 with her myself back when the T5 fixture mfr. (Shenzen) had an issue with reflectors being installed backward/upside down.

Back in the early days of Usenet and before (ARPANET, etc.) most/much of the traffic was academic, so it wasn't all that unusual to find yourself in an exchange with... well... academicians (Celebrity Brains).

I guess nowadays much of it is one-way via tweeter(?)

 

[Tarzanfam]

Cool. I've had an exchange or 2 with her myself back when the T5 fixture mfr. (Shenzen) had an issue with reflectors being installed backward/upside down.

Back in the early days of Usenet and before (ARPANET, etc.) most/much of the traffic was academic, so it wasn't all that unusual to find yourself in an exchange with... well... academicians (Celebrity Brains).

I guess nowadays much of it is one-way via tweeter(?)

That's awesome! I was surprised to see that she was writing me, asking me questions and interested in helping. And not because I didn't think someone like that would be, but because I just would not expect to find someone with that kind of knowledge on a facebook group and interested in my little friend. It was super kind of her to take the time to help me learn!

 

[Klyde O'Scope]

AFAIK, the FB group and http://www.uvguide.co.uk/index.htm grew up hand-in-hand (BICBW).

Was it your little friend of the Chamaeleo, Furcifer, or Pogonish—persuasion?

 

[kinyonga]

@Jevin said..."Clarifies it, with what I've learned in biology classes, I tend to let nature do it's thing as it's had millions of years of evolution to get to this point, so humanities understanding and ability to change it for the better is limited in a certain way"...the thing is with the keeping of chameleons, IMHO what we do is not natural and we have to compensate for it. The insects we use are not the ones they will eat in the wild and we don't feed the insects exactly what they would eat in the wild....and how can the UVB really be the same as sunlight..so we may/do have to give some D3 and other things to compensate.

 

[kinyonga]

@Jevin ...IMHO...the aim needs to be that we give less than enough vitamin D3 and hope we provide a good enough UVB source that the chameleon can produce the rest it needs from exposure to that UVB.

This way there should be no calcium deposits in the soft tissues.