SusanJ wrote:Interesting that manipulating serotonin was associated with less Aβ accumulation.
We certainly understand that Aβ is an immune response. Leaves me wondering how/why would serotonin play into impacting that immune response under normal circumstances?
Immunomodulatory capacity of the serotonin receptor 5-HT2B in a subset of human dendritic cells.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5788853/ (Gonna have to reread this one when I have more time.)Our results expand the biological role of 5-HT2B which may act not only as a neurotransmitter receptor, but also as an important modulator of both innate and adaptive immune responses.
Yes, I had a read and it mentioned that apart from its role in regulating gastrointestinal motility (GI tract), vasoconstriction, blood clotting, hemostasis (cardiovascular system), mood and cognition (CNS), serotonin is also involved in the regulation of inflammation and immune functions via controlling the release of cytokines and chemokines in a cell type-dependent manner. It is interesting as well as some think depression is related to, or caused by, inflammation, as well. Here it also describes anti-inflammatory effects http://onlinelibrary.wiley.com/doi/10.1 ... 2.231/full
"Studies have found the following important functions of fluoxetine related to the central nervous system: neuroprotection; anti-inflammatory properties similar to standard drugs for the treatment of inflammatory conditions; antioxidant properties, contributing to its therapeutic action and an important intracellular mechanism underlying the protective pharmacological effects seen in clinical practice in the treatment of different stress-related adverse health conditions; and antiapoptotic properties, with greater neuron survival and a reduction in apoptosis mediators as well as oxidative substances, such as superoxide dismutase and hydrogen peroxide."
And depression, which can reflect a serotonin problem, is linked to a higher risk of AD, but treating depression leads to lower conversion.
https://www.ncbi.nlm.nih.gov/pubmed/29179578Impact of SSRI Therapy on Risk of Conversion From Mild Cognitive Impairment to Alzheimer's Dementia in Individuals With Previous Depression.
https://www.ncbi.nlm.nih.gov/pubmed/29438781A long-term treatment with antidepressants such as selective-serotonin-reuptake inhibitors (SSRIs) is known to reduce the risk of AD in patients with depression and, SSRIs, such as fluoxetine, increase the release of TGF-β1 from astrocytes and exert relevant neuroprotective effects in experimental models of AD. We propose the TGF-β1 signaling pathway as a common pharmacological target in depression and AD, and discuss the potential rescue of TGF-β1 signaling by antidepressants as a way to prevent the transition from depression to AD.
That looks interesting, will have a read.
And another vote for omega-3s.
N-3 PUFA diet enrichment prevents amyloid beta-induced depressive-like phenotype. (Rat study)https://www.ncbi.nlm.nih.gov/pubmed/29203442Results showed that n-3 PUFA enriched diet prevented the Aβ- induced depressive-like behaviors, as reveled by the reduction in the immobility time in the FST test. Furthermore, n-3 PUFA rich diet exposure reverted also serotonin and neurotrophin level reduction in prefrontal cortex of Aβ treated rats. Taken together, our data support the concept that supplementation of diet with n-3 PUFA represents a valid approach to reduce the risk of developing depressive symptoms, as well as reducing the risk of Aβ-related pathologies, such as AD.
Omega 3 oil is definitely something I read was good for depression as well, in the past and mood. Might be a link there.
Interesting stuff. And now I wonder how the gut / vagus nerve play into all of this, in terms of serotonin and signaling from the microbiome in the gut...hmm. I see some new rabbit holes, here.
Yes I can see that! I read somewhere that most of the serotonin is in the gut, rather than the brain! It seems it may interact in several different ways.
Here is an interesting article about How to increase serotonin in the human brain without drugs
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2077351/
I was interested to see this section, as it seems to tie in with the recent article on here about positive thinking and ageing..and how that improved things for those with APOE4. Could it be a link to serotonin, perhaps, amongst other things?
"The constitution of the WHO states “Health is a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity.”20 This may sound exaggerated but positive mood within the normal range is an important predictor of health and longevity. In a classic study, those in the lowest quartile for positive emotions, rated from autobiographies written at a mean age of 22 years, died on average 10 years earlier than those in the highest quartile.21 Even taking into account possible confounders, other studies “found the same solid link between feeling good and living longer.”12 In a series of recent studies, negative emotions were associated with increased disability due to mental and physical disorders,22 increased incidence of depression,23 increased suicide24 and increased mortality25 up to 2 decades later. Positive emotions protected against these outcomes"
"Several studies found an association between measures related to serotonin and mood in the normal range. Lower platelet serotonin2 receptor function was associated with lower mood in one study,30 whereas better mood was associated with higher blood serotonin levels in another.31 Two studies found that greater prolactin release in response to fenfluramine was associated with more positive mood.32,33 The idea that these associations indicate a causal association between serotonin function and mood within the normal range is consistent with a study demonstrating that, in healthy people with high trait irritability, tryptophan, relative to placebo, decreased quarrelsome behaviours, increased agreeable behaviours and improved mood.34 Serotonin may be associated with physical health as well as mood"
Ways shown to improve levels without drugs include:
self-induced changes in mood can influence serotonin synthesis.
exposure to bright light
exercise
possibly diet but unclear (tryptophan)
I definitely find personally exercise and music help me, and being outside in the sunshine, as much as the meds. Or the combination together. I wonder if any of this would be helpful for those who are not suffering or have had depression in the past, or whether it is mainly helpful to those people. I guess, it may be particularly of benefit to them. Around 1 in 4 of us do struggle with it at some point so i guess it is something to be aware of. And it seems to be linked with first stages of AD as well, as well as possibly being linked to APOE4 in women https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2583456/