The other day I was having a conversation with forum member Millbrook about the potential use of melatonin (one of my favorite supplements) for PD and I was discussing how well PD deficits align with what melatonin seems to offer based on other studies, but I was dismayed by the lack of meaningful human studies of the two together and my hesitancy to even mention melatonin for PD on this forum due to the lack of a useful human study of melatonin in PWP.
Here is a link to that brief exchange in which I mentioned that from other studies, it appears that melatonin ticks many of the boxes that would be desirable in a PD supplement or drug :
Today I decided to see if there were any new studies on this subject, and I found this new (May 2020) randomized, double blind, placebo controlled study at just 10 mg/day! It is not the dose I would like to have seen, but this is a real step in the right direction!
Melatonin is a highly potent antioxidant among many other things and the study shows that melatonin increases glutathione significantly and PWP seem to be more focused on glutathione, but directly and indirectly, melatonin is a much more potent antioxidant and antiinflammatory than glutathione because melatonin upregulates the gene expression of glutathione peroxidase, catalase and superoxide dismutase.
Melatonin itself is a very potent scavenger of reactive oxygen species/hydroxyl radicals, reactive nitrogen species and peroxynitrite! Melatonin also has potent antiinflammatory effects and lowers multiple inflammatory cytokines and mediators that are known to be elevated in PWP.
Melatonin Lowers IL-1b, IL-6, Tnf-alpha, NF kappa-B, IL-17, MMP-2, MMP-9 and IL-8 among many others. You may remember the chemokine IL-8 from a post I wrote about it where I described that IL-8 level is low in the blood of PWP, but maliciously elevated in the cerebrospinal fluid (CSF).
Well melatonin enters the CSF and melatonin and its metabolites not only easily cross the blood brain barrier (BBB), but also repair damage to the BBB! In PWP, brain inflammation and brain oxidative stress are elevated and feed off of each other in a vicious cycle that can destroy neurons and cells of all types and melatonin works against this cycle by reducing inflammation and excess oxidative stress.
IL-8 is higher up in the inflammatory cascade and reducing it is very important because a reduction of IL-8 means a reduction of proinflammatory mediators that are downstream from IL-8 in the inflammatory cascade and that is a big deal! Here is a link to that post that helps tie the usefulness of lowering IL-8 in PD.
As you can see from that post, lowering the IL-8 level in the brain and CSF should clearly be beneficial for PWP and people with MS. Many diseases present with elevated IL-8 levels in the blood, but MS and PD show elevation in the CSF and this can be very damaging and nothing that PWP or MSP want!
Another important point about the antioxidant power of melatonin itself and not even counting the melatonin induced upregulation of the bodies own potent antioxidants is the fact that melatonin can neutralize as many as 10 oxygen radicals because once it neutralizes a radical it becomes a metabolite that can also reduce oxygen radicals and this process just keeps repeating with different melatonin metabolites, whereas other antioxidants like vitamin C and vitamin E which might only be able to neutralize one or possibly two oxygen radicals and this starts to give you a clue of what melatonin can do in the body, including the brain because melatonin easily enters all tissues of the body. Add in the potent antiinflammatory effects which melatonin can express in the brain and body in general and you start to get an idea of the potential value of melatonin in PWP.
There are many other positive health effects that melatonin is known for such as its ability to act as a potent anticarcinogenic at high dose.
Finally, a study I have waited years for, has arrived and hopefully it will be one of many human studies that attempts to show the value of melatonin for PWP! Now it looks like melatonin could potentially be useful for Covid-19 and PD at the same time! Future studies could consider pharmacologic dosing of melatonin in PD patients.
Do not think that you can just jump in and start using melatonin without your doctor's consent and supervision because some people can not tolerate melatonin and it may not be compatible with the medications you are currently taking, so your doctor's or professional health care provider's approval and supervision is definitely needed to stay as safe as possible!