How Beta-endorphins are formed is where things get interesting. They are produced from the cleaving of a substance pre-pro-opiomelanocortin produced in the pituitary into pro-opiomelanocortin (POMC) a peptide neurotransmitter.
Ok no big deal. But what I learned next was the stunner. See the tumor suppressor gene called p53 gene is for one crucial to the production of POMC. Bear with me as I try, over these next several blog postings, to pull these facts and how important is the p53 gene.
POMC is acted on in the pituitary gland in the central nervous system (CNS) but also elsewhere in the body. Including the peripheral nervous system (PNS) to produce several proteins neurotransmitters, for example Beta-endorphin but there are several others.
POMC is amazing and is called a neuropeptide. Which is made up of amino acids, the building blocks of proteins. POMC depending on how cut by enzymes into smaller neuropeptides can act on many different receptors to activate many different cellular functions.
For example, the two shorter neuropeptides from POMC-melanocyte stimulating hormone (MSH) and adrenocorticotropin (ACTH). MSH stimulates the production of melanin, which gives skin its dark color and for those with lighter colored skin a tan following ultraviolet light exposure.
As melanin is important to protect our DNA in cells as it absorbs >99.9% of UV light.1 As ultraviolet light is made up of both UV-A and UV-B fractions and both can damage our DNA and cause cancer. The distinction between UV-A and UV-B is important.
But first a bit about sun screens which as those of you who have followed what I have written before, know that I am not a big fan of sun screen lotions. Well they are worse than I thought. So, let me be more specific as I have not been before.
I am not a big fan of both the older ones and the current ones as they block UV-B which is what helps produce vitamin D3. UV-A doesn’t. Despite “updates” to the chemicals used in them, there is no telling if they will realize the newer chemicals used in sunscreens cause problems.
See in the past we probably did significant damage to ourselves by what they don’t block UV-A. Many older sunscreens contained chemicals like para amino butyric acid (PABA) and octinoxate. Both which could cause several harmful things.
Then the sun screen chemical octinoxate and one still often used today, oxybenzone are thought to cause damage to sea coral.2 Some areas banning them but significant damage having already been done. Second naturally formed vitamin D3 in skin attaches to the vitamin D binding protein (DBP).
DBP is important in immune function as it is what is called a macrophage activating factor (MAF). MAF may be effective against cancer.3 Reduced or no UV-B then reduced or no vitamin D3, DBP or MAF. Don’t worry if your main source of vitamin D3 is taken orally as it’s also attached to DBP but in the liver.
Well there are other problems with the sun screen chemicals like PABA and octinoxate, though they are used infrequently now, that they were used may be an issue for those that did. These two only block UV-B but not UV-A.
Thus, sunscreen containing these compounds gave those who used them a false sense of protection. Thus, no protection from UV-A exposure. Protecting from UV-A may be important in preventing skin cancer.4 UV-A exposure appears to be associated with melanoma a less common, but more deadly type of skin cancer.5
1. Meredith P, Riesz J (2004). “Radiative relaxation quantum yields for synthetic eumelanin”. Photochemistry and Photobiology. 79(2): 211-216.
2. A. Down CA, Kramarsky-Winter E, Segal R, et al. (February 2016). Toxicopathological effects of sunscreen UV filter, oxybenzone (Benzophenone-3) , on coral planulae and cultured primary cells and its environmental contamination in Hawaii and U.S. Virgin Islands. Arch Envir Contamin Toxicol. 70(2):265-288.
3. Yamamoto N, Suyama H, Yamamoto N (July 2008). Immunotherapy for prostrate cancer with Gc protein derived macrophage activating factor, GcMaF” Translational Oncology. 1 (2):65-72.
4. Poon T, Barneston R, Halliday GM. (2003). Prevention of immunosuppression by sunscreens in humans is unrelated to protection from erythema and dependent on protection from ultraviolet A and in the face of constant ultraviolet B protection. J Invest Dermatol. 121(1):184-90.
5. Wang SQ, Sellow R, Berwick M, et al. (May 2001). Ultraviolet light and melanoma: a review. J Am Acad Dermatol. 44(5):837-46
*The information posted above is for educational purposes only. Always check with your doctor before initiating any changes in your medical treatment. If you do not, then The Two-Minute Health Fact, Dr. Judson Somerville, nor The Optimal Dose is responsible!