In 2015-2016 Mitosynergy hired me to help them get an FDA letter of acknowledgement for their new dietary ingredient cuprous niacin. The owner and CEO of Mitosynergy went to Egypt to obtain a remedy for his nephew who had suffered a spinal cord injury. He came back with a protocol for the production of what the Egyptians called copper nicotinate. We call it cuprous niacin to emphasize the+1 oxidation state. Much of the toxicology assessment had already been performed in three species of fish grown for food in Egyptian fish farms.
Top left: The structure of cuprous niacin. Bottom left: images of cuprous niacin and cupric glycinate, a common copper supplement. Other images are of crystals in all of ther cuprous, +1, beauty. Mitosynergy likes to refer to cuprous copper as “proper copper” and cupric copper as “toxic copper.” Note the difference in color.
Asking the right questions
We used an FDA NDI draft guidance that was a little less polished to the one available at the link.
Short term toxicology
Thanks to some very resourceful Egyptian scientists, a lot of the toxicology tests had already been performed. These clever people performed blood work including liver enzymes and more in inexpensive fish. It should be noted that they were also looking for a dietary supplement to decrease infections in farm raised fish. Mitosynergy had also contracted a small clinical trial with human subjects. Extensive blood work was performed for these participants. In both the fish and human studies, researchers were looking for liver enzymes in the blood and changes in red and white blood cells. No indications of toxicity were found.
The answer that got the letter of acknowledgement
The final piece of data that got Mitosynergy the “letter of acknowledgement” from the FDA was proving that copper and niacin dissociate under the acidic conditions of the stomach. Both the lawyers and the FDA examiner suggested this question be answered. In a way, it was disappointing in that consuming copper nicotinate would be no different than consuming foods rich in both copper and niacin. I demonstrated copper niacin dissociation by creating stomach conditions with hydrochloric acid, cuprous niacin, and potato starch. I had found some references for copper binding to various cereal grains and starches. I centrifuged this stomach like mixture to pellet the potato starch. I measured the UV absorbance of the supernatant.
A 1% wt/vol solution of niacin has an absorbance of 432, assuming a 1cm path length. This “extinction coefficient” was used to calculate the amount of niacin in the supernatant.
Mal J Nutr 2: 49-65, 1996 Development of a HPLC method for the simultaneous determination of several B-vitamins and ascorbic acid Khor Swan-Choo & Tee E-Siong
The potato starch pellet was sent to my colleague David Luttrell at LP Analytical to use his ICP mass specrometry to show copper bound to the potato starch.
Szymońska J, Wieczorek J, Molenda M, Bielańska E.(2008) Uptake of Cu2+ by starch granules as affected by counterions. J Agric Food Chem. 56(11):4054-9.
Relevant questions for other dietary ingredients
Once we had proven dissociation under conditions of the stomach, questions concerning developmental toxicity and genetic toxicity did not need to be addressed for the FDA letter of acknowledgement. These FDA questions are nonetheless good questions.
Perhaps we could have tested the copper niacin on newly hatched chickens and monitored their development. The Egyptians were testing cuprous niacin as a means of controlling bacterial infections in farm raised fish. Perhaps cuprous niacin could help a chicken farmer cut down on the use of antibiotics.
We never addressed the issue of genetic toxicity because cuprous niacin, as sold by Mitosynergy, is in the +1 oxidation state. The Cu(II) +2 oxidation state may be a problem.
Picolinic acid based Cu(II) complexes with heterocyclic bases–crystal structure, DNA binding and cleavage studies. Eur J Med Chem. 2014 May 22;79:117-27. Pulimamidi RR, Nomula R, Pallepogu R, Shaik H.
DNA single and double strand breaks induced by aliphatic and aromatic aldehydes in combination with copper (II). Free Radic Res. 1996 24(5):325-32. Becker TW, Krieger G, Witte I.
. These are just two publications along the theme of conditional Cu(II) toxicity. We may have been able to test for DNA strand breaks in mammalian cells with the Comet Assay We may also have used the Ames test to compare the ability of cuprous niacin and cupric dietary supplements to cause reverse mutations in bacteria.
In 2018 I helped Mitosynergy register cuprous niacin with Health Canada. Health Canada was concerned that cuprous niacin was not naturally occurring. My contribution was to provide evidence from the peer reviewed literature that plants store copper in the Cu(I) oxidation state.
Plants also express Cu/Zn superoxide dismutase. Like we demonstrated for cuprous niacin, the amino acid histidine may no longer bind copper when it is protonated in the pH 1.7-2 environment of the stomach. I performed an in silico pepsin digest followed by a small intestine digest with trypsin. Chymotrypsin was left out. Copper binding histidines are marked with red stars. Remaining histidines, marked with cyan stars, may be available to bind copper as peptides become shorter. In the educing environment of the small intestine, one can speculate that this copper will be in the Cu((I) oxidation state.
Red stars mark the copper binding histidines. Lines mark an in silico digestion with pepsin at pH 2. The copper is predicted to dissociate from histidine in the stomach. We may predict that when the kidney bean meal enters the duodenum, copper may reassociate with both histidines and any niacin in the kidney bean meal.
From Transdermal Delivery to Cosmetics work
Mitosynergy had some thoughts about transdermal delivery of cuprous niacin as a mineral nutrient in the +1 oxidation state. Do we register cuprous niacin as a drug which would really cost the company? Could we consider the complex as a delivery system for delivery of copper in the +1 oxidation state directly to the blood? After discussing this with a lawyer, it was decided to go the cosmetics route.
New Cosmetic ingredients, not as easy as one would think
A plan B was floated that Mitosynergy simply put the cuprous niacin in a dermal cream. An FDA certified company that compounds cosmetics was contacted. They are not permitted to compound anything unless all ingredients are INCI registered.
Plan B through the dermal application wall sent us on a detour, that felt like splattering into a legal wall. We came back to the same FDA question, “Is it a Cosmetic, a Drug, or Both? (Or is it a Soap)?”
International Nomenclature of Cosmetic Ingredients INCI
Not only were we required to supply chemical and production information, but were were also required to select from a list of many dozen possible functions. We chose color agent. Lakes are a class of pigments composed of organic dyes that have been rendered insoluble by interaction with a compound of a metal. Many of the images of cuprous niacin in the dry form, appear to be larger than the 1000 nm cut off. We could have proven as much after defined incubations in sweat like solutions.
If not a color, is copper nicotinate an antimicrobial?
Parabens are currently an FDA approved preservative in cosmetics. The FDA states that the literature is continuously being monitored for the safety of parabens. They seem to be tolerated only because a better alternative does not exist. We had explored the potential antimicrobial action of cuprous niacin as a dermal drug. I had devised a way of processing pig skin from a local slaughter facility into a substance that was somewhere between agar plates used to grow bacteria or molds and the native skin. Could cuprous niacin in a Shea butter or a related emulsion penetrate into hair follicles that tend to support microbial growth?
The pig skin substance was incubated at 37oC with a topical application of cuprous niacin in Shea butter. The skin was cut into sections and photographed at 40x. The black object on the left is a hair follicle.
Note the blood vessels in the cartoon of a human skin section. The concern of cosmetic compounds entering the general circulation is easy to understand. Perhaps many consumers would probably prefer risking cuprous niacin entering their circulation than an artificial dye. While the road to proving antimicrobial activity of cuprous niacin is a long and expensive one, cuprous niacin could be preferable to parabens.
Safety studies performed on cosmetic ingredients may be submitted to the Cosmetic Ingredient Review board. I’ve read the reviews of copper and niacin compounds used as cosmetic ingredients. Elaborate toxicology studies were performed on some and relatively simple studies performed on others. There publications are peer reviewed and can be given to those who use or distribute your cosmetic product.
The FDA has a voluntary cosmetic registry program (VCRP). This registry is not only for the individual ingredients but also for the entire formulation and the manufacturing process. Having each ingredient registered with INCI may protect you and your customers. A currently accepted ingredient may be shown to be toxic in some individuals. Two cosmetic common cosmetic ingredients may later be shown to interact to produce a toxin.