
Omega-3 fatty acid DHA has a role in diabetic retinopathy in mice - nocoder
https://www.nature.com/articles/d41586-017-07678-8?WT.mc_id=TWT_NA_1711_BHNVDARKFATTYACIDS_PORTFOLIO
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carlsborg
* "Dietary intake of DHA (omega 3 fatty acid) is associated with several health benefits, including normal brain and eye function2. .. _mice that lack the protein Mfsd2a_ , which transports DHA across the blood–brain barrier into the brain, develop severe retinal and brain dysfunction3"

* A quick search shows that a) DHAs are vital for brain function and b) the role of Mfsd2a is known: "Mfsd2a-deficient (Mfsd2a-knockout) mice show markedly reduced levels of DHA in brain accompanied by neuronal cell loss in hippocampus and cerebellum, as well as cognitive deficits and severe anxiety, and microcephaly. " [https://www.nature.com/articles/nature13241?WT.feed_name=sub...](https://www.nature.com/articles/nature13241?WT.feed_name=subjects_phospholipids)

* OP paper says: DHA and DHA oxidation produced epoxide metabolites "are associated with beneficial retinal effects" and an enzyme called sEH degrade them to form 19,20-DHDP, "suggesting that sEH has a causal role in diabetic retinopathy." (which is "a major cause of blindness in middle age").

* Then .. plot twist: And then "Hu and colleagues showed that it is the production of 19,20-DHDP, rather than the reduction in DHA or epoxide molecules, that is the key trigger of vascular degeneration.

* "19,20-DHDP acts through a different mechanism from that of another player in retinopathy — vascular endothelial growth factor (VEGF). This protein is induced under low-oxygen conditions.."

* So the real villain here is increased sEH and the question for future research is "what triggers increases in sEH production in diabetic retinopathy"

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terminalcommand
I've had type 1 diabetes for 12 years, in the recent couple of years I
occasionally take Omega3 and DHA supplements every day. My daily intake is 300
mg of Omega 3, 180 mg of EPA, 120 mg of DHA.

I couldn't really understand the full article. Does this mean I should switch
to pure Vitamin D supplements instead of DHA?

As far as I could find, current understanding is that Omega3 (EPA and DHA)
help prevent vascular damage and retinopathy.

"Mice receiving the omega-3 rich diet were observed to have 40-50% less
initial retinal vessel loss compared to omega-6 fed mice. As a result, the
omega-3 group had a similar 40-50% reduction in pathological vessel growth.
The results were virtually identical in the Fat-1 mice, confirming that
increased retinal omega-3 levels inhibited neo-vascularization." (Source:
[http://www.sciencebasedhealth.com/-DHA-and-EPA-May-
Protect-A...](http://www.sciencebasedhealth.com/-DHA-and-EPA-May-Protect-
Against-Retinopathy-W71.aspx))

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WilliamSt
Please do not take advice about your health from hacker news. Type 1 diabetes
is a serious condition. Consult a medical professional about your diet and
medication.

~~~
DoofusOfDeath
That being said, you may find it worthwhile to work with an endocrinologist
who stays abreast of this kind of research.

~~~
dominotw
Most doctors are totally clueless regarding nutrition or supplements.

How do you even go about finding a doctor who "stays abreast of this kind of
research" .

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DoofusOfDeath
Depends on where you live. If it were me, I'd start with doctors who are
actively involved with Joslin, or with a research-oriented teaching hospital
like Mass. General.

If you don't live close to a city with one of those, I'm not sure what your
best options would be.

If it's a huge deal, you might consider establishing a relationship with a
specialist who you have to travel a long distance to visit, or even consider
relocating.

EDIT: It's also been my experience that the occasional clinical
endocrinologist NOT affiliated with a research / teaching hospital stays on
top of current research. If your GP has been in working locally for a while,
he/she may know which local endocrinologists are the sharpest, and may trust
you well enough to make a few recommendations.

Also, I'm not sure if this is just an anomaly, but I've found that the local
endocrinologists who immigrated from Poland are really on top of things.

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hannob
"The molecule 19,20-dihydroxydocosapentaenoic acid, formed by the metabolism
of a fatty acid involved in normal brain function, promotes the development of
a diabetes-associated form of blindness in a mouse model."

tl;dr Mice should be really careful when consuming too much omega-3 fatty
acids.

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qwerty456127
Wow! So dark...

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DoofusOfDeath
Ah crap! You may have retinopathy! ;)

