Vitamin A (and ATRA) Upregulate Oxytocin via CD38

 A familiar site to Maja, the confluence of the Sava and the Danube

Today’s post is to document an interesting discovery by Maja, one reader of this blog.  She is just ahead of some Korean researchers, who very recently published a paper in Experimental Neurobiology on the same subject.

Maja noticed that giving a small dose of fish oil produced the same benefits as those often claimed for Oxytocin; she then did some investigation and noted that an enzyme called CD38 upregulates oxytocin in the brain.  The level of CD38 is affected by inflammatory cytokines and certain vitamins.  In particular, all-trans retinoic acid (ATRA) increases CD38. All-trans retinoic acid (ATRA) is made in the body from vitamin A.  ATRA is also called vitamin A acid.

Maja suggested this paper:-

All-trans Retinoic Acid Upregulates Reduced CD38 Transcription in Lymphoblastoid Cell Lines from Autism Spectrum Disorder

Deficits in social behavior in mice lacking the CD38 gene have been attributed to impaired secretion of oxytocin. In humans, similar deficits in social behavior are associated with autistic spectrum disorder (ASD), for which genetic variants of CD38 have been pinpointed as provisional risk factors. We sought to explore, in an in vitro model, the feasibility of the theory that restoring the level of CD38 in ASD patients could be of potential clinical benefit. CD38 transcription is highly sensitive to several cytokines and vitamins. One of these, all-trans retinoic acid (ATRA), a known inducer of CD38, was added during cell culture and tested on a large sample of N = 120 lymphoblastoid cell (LBC) lines from ASD patients and their parents. Analysis of CD38 mRNA levels shows that ATRA has an upmodulatory potential on LBC derived from ASD patients as well as from their parents. The next crucial issue addressed in our study was the relationship between levels of CD38 expression and psychological parameters. The results obtained indicate a positive correlation between CD38 expression levels and patient scores on the Vineland Adaptive Behavior Scale. In addition, analysis of the role of genetic polymorphisms in the dynamics of the molecule revealed that the genotype of a single-nucleotide polymorphism (rs6449182; C>G variation) in the CpG island of intron 1, harboring the retinoic-acid response element, exerts differential roles in CD38 expression in ASD and in parental LBC. In conclusion, our results provide an empirical basis for the development of a pharmacological ASD treatment strategy based on retinoids.

In December some Korean researchers also suggested that ATRA might be used therapeutically to increase Oxytocin.  Maja discovered that vitamin A can also be used, which makes sense.

The Korean paper reviews the existing literature and clinical trials on oxytocin in autism, and I suggest those interested should read it.

Some people clearly benefit from oxytocin, some do not and some suffer side effects.

In those that benefit from oxytocin, it might be simpler to upregulate the body’s own oxytocin via ATRA, or vitamin A.

Is this proof?

Of course there are other explanations possible for what Maja has noted.  She was using fish oil as a source of vitamin A, so it could be related to the other constituents.

However, I for one think it is highly plausible and does fit nicely with the ideas put forward by the Korean researchers and the earlier paper.

Vitamin A for all?

We know that autism genes include many for oxytocin, oxytocin receptors and indeed CD38, so anyone with those genes dysfunctional might benefit.

However, as we saw with biotin, more people may be affected to a lesser degree.

CD38 affects oxytocin secretion in the brain and CD38 is affected by inflammatory cytokines, so at times of elevated cytokine expression, CD38 and oxytocin might be reduced in people with no relevant genetic dysfunction.

You can have too much vitamin A, this is called Hypervitaminosis A.  You cannot suffer this condition by eating fruit and vegetables, but you can by eating too much preformed vitamin A from foods (such as fish or animal liver), supplements, or prescription medications; it can be prevented by ingesting no more than the recommended daily amount.

High intake of provitamin carotenoids (such as beta carotene) from vegetables and fruits does not cause Hypervitaminosis A, as conversion from carotenoids to the active form of vitamin A is regulated by the body to maintain an optimum level of the vitamin. Carotenoids themselves cannot produce toxicity.

So, too much cod liver oil can be bad for you, but you can eat carrots like Bugs Bunny and do no harm.  If you really overdo it, your skin may change colour to orange, something called carotenosis

You can buy vitamin A supplements as the preformed vitamin or as beta carotene.

Too much of a good thing?

In times gone by, children used to be given a tablespoon of cod liver oil daily, as a good source of vitamin D and vitamin A.  These days that amount of both vitamins would be seen as excessive.  Excess of both vitamins is bad for you, but easy to achieve, by accident, while trying to do a good thing.

Maja’s Dose

Maja achieved her positive results with a modest dose of fish oil (using 40% of one capsule) giving 3-4000 IU of vitamin A.

This is actually quite a high dose of vitamin A, if you look at the maximum safe dose.

I think many people are giving kids with autism much larger doses of fish oil and thus far too much vitamin A and D.  This has been raised as an issue by Seth, another reader of this blog.

CD38

CD38 has many other functions other than regulating oxytocin. In people who have an oxytocin dysfunction due to an upstrean CD38 dysfunction, correcting the lack of CD38 might be particularly beneficial.   

CD38 is used as a prognostic biomarker for leukemia.  This is a complex area of science.  In essence, it is an accepted fact that increased CD38 expression is associated with favorable prognosis in adult acute leukemia.

Leukemia is associated with Down Syndrome. 

Not surprisingly, both vitamin A and ATRA can be beneficial in treating leukemia.

ATRA (All Trans-Retinoic Acid) for acute myeloid leukaemia (AML)

CD38 expression is apparently easy to measure.

Perhaps in those numerous oxytocin trials for autism, they might want to bother measuring CD38?

The Recent Korean Paper

Here is what the Koreans have to say about Oxytocin:-

 Is Oxytocin Application for Autism Spectrum Disorder Evidence-Based?

CD38 is a transmembrane antigen that has been studied as a negative prognostic marker for chronic lymphocytic leukemia [72]. CD38 participates in the oxytocin secretion in the brain and affects maternal nurturing and social behavior [73]. Plasma levels of oxytocin are strongly reduced in CD38 knockout mice (CD38-/-mice) and subcutaneous oxytocin injection or lentiviralvector-mediated delivery of human CD38 into the hypothalamus rescued social memory and maternal care in these mice [73].

CD38 transcription is highly sensitive to cytokines and vitamins, including all-trans retinoic acid (ATRA), a known inducer of CD38 [75]. In a study on lymphoblastoid cell lines in patients with ASD and their parents, ATRA exhibited an upmodulatory potential on CD38 mRNA [75]. Although there have been almost no follow up studies on ATRA and ASD treatment, there is a possibility that substances affecting CD38 expression, such as ATRA, may be potential therapeutic candidates