vitamin A

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jimmylegs
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vitamin A

Post by jimmylegs » Sun Nov 01, 2020 12:36 pm

Overview

Vitamin A Fact Sheet for Health Professionals
https://ods.od.nih.gov/factsheets/Vitam ... fessional/
Vitamin A Fact Sheet for Consumers
https://ods.od.nih.gov/factsheets/VitaminA-Consumer/
Hypervitaminosis A
https://www.healthline.com/health/hypervitaminosis-a
"Most people develop vitamin A toxicity by taking high-dose dietary supplements, possibly ... in an attempt to prevent or treat diseases [ .... or] by long-term use of certain acne treatments ... such as isotretinoin (Sotret, Absorica)."

Laboratory Medicine Best Practice Guideline: Vitamins A, E and the Carotenoids in Blood (2014)
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4159783/

Food sources (retinol and carotenoid)



Sample Toxicity Reports

Acute hepatomegaly with severe liver toxicity due to all-trans-retinoic acid (2000)
https://haematologica.org/article/view/1694
pdf dl https://haematologica.org/article/view/1694/7251

" ... To our knowledge, only two other cases of severe acute toxicity due to this drug have been reported ,,,"

The acute and chronic toxic effects of vitamin A (2006)
https://pubmed.ncbi.nlm.nih.gov/16469975/

"... Emerging evidence suggests that subtoxicity without clinical signs of toxicity may be a growing concern, because intake from preformed sources of vitamin A often exceeds the recommended dietary allowances (RDA) for adults, especially in developed countries. Osteoporosis and hip fracture are associated with preformed vitamin A intakes that are only twice the current RDA. ... "

Refractory hypercalcemia owing to vitamin A toxicity in a 4-year-old boy (2020)
https://www.cmaj.ca/content/192/25/E671.short

" ... Ultimately, his vitamin A level was 2.5 times greater than the normal range, which was likely caused by high vitamin A intake. ... Our patient was ingesting 1850–3780 IU/kg/day of predominantly provitamin A for years. While children can develop toxicity at lower total doses of preformed vitamin A than those required to cause toxicity in adults, our case is somewhat unusual in that the patient was consuming large quantities of provitamin A from fruits and vegetables, notably kale.3,6,7 One explanation is that intake of large quantities of provitamin A and preformed vitamin A from cod liver supplements together may have caused toxicity, as the effect of high levels of preformed vitamin A on the metabolism of provitamin A may be synergistic.4 ... "
https://www.who.int/news-room/q-a-detail/q-a-coronaviruses

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jimmylegs
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vitamin A & MS research

Post by jimmylegs » Sun Nov 01, 2020 3:51 pm

Serum Levels of Antioxidant Vitamins and Lipid Peroxidation in Multiple Sclerosis (2002) NEW
https://bit.ly/3f5MTJV

"... Twenty-four patients (35.9 ^ 7.3 years) with secondary progressive MS were included in the present study ...
Serum levels of ascorbic acid, alpha tocopherol, retinol and beta-carotene were found to be lower in MS patients during exacerbation than in the healthy age- and sex-matched control group ...
Parameter......................MS patients...................Controls
Retinol (mmol/l) (Ranges)...2.07 ^ 0.21* (1.39–2.48).....2.53 ^ 0.26 (1.67–3.29)"
(given the conversions below i will presume they meant mumol??)

Retinol measurements and retinoid receptor gene expression in patients with multiple sclerosis (2002) NEW
https://journals.sagepub.com/doi/abs/10 ... 502ms858oa

"...
Plasma retinol means (ug/dl)
RRMS IFN-.....46.56 (1.62 umol/l)
RRMS TOT.......50.41 (1.76 umol/l)
MS IFN-.....50.86 (1.78 umol/l)
MS TOT.......52.84 (1.84 umol/l)

RRMS IFN+.....57.80 (2.02 umol/l)
CONTROLS....57.95 (2.02 umol/l)
...
These studies suggest an association between plasma retinol levels and clinical disease activity in patients with MS and that treatment with IFN-β1a may be associated with activation of specific retinoid receptor subtypes."

ug/dl units conversion via http://www.scymed.com/en/smnxtb/tbcbmng1.htm

Retinol levels are associated with magnetic resonance imaging outcomes in multiple sclerosis (2012)
https://journals.sagepub.com/doi/abs/10 ... 8512457843
... Each 1 µmol/L increase in serum-retinol reduced the odds (95% confidence interval) for
new T1 gadolinium enhanced (Gd+) lesions by 49 (8–70)%, new T2 lesions by 42 (2–66)%,
...
Serum-retinol also predicted new T1Gd+ and T2 lesions six months ahead. The associations were not affected by HLA-DRB1*15, or serum levels of 25-hydroxyvitamin D, eicosapentaenoic acid or docosahexaenoic acid. ...

The effect of vitamin A supplementation on stimulated T-cell proliferation with myelin oligodendrocyte glycoprotein in patients with multiple sclerosis (2012) NEW
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3505320/
... results suggest supplementation with retinyl palmitate [25000 IU/d retinyl palmitate] in patients with MS reduce MOG stimulatory effects on T-cells.

Fat‐soluble vitamins as disease modulators in multiple sclerosis (2012) NEW
https://onlinelibrary.wiley.com/doi/abs ... /ane.12045

"For vitamin A and E, level 4 and 5 evidence exists for a modulatory effect in MS... All the fat‐soluble vitamins have ... been demonstrated to be effective in different animal models for the disease, and vitamin A and E have biological properties that could be relevant for MS pathogenesis. Thus, vitamin A and E seem to be promising candidates for future case–control and cohort studies."

Impact of vitamin A supplementation on RAR gene expression in multiple sclerosis patients (2013) NEW
https://link.springer.com/article/10.10 ... 013-0090-9
... results show that vitamin A supplementation [25000 IU/d retinyl palmitate] can significantly downregulate the expression of RAR-α gene in PBMCs of MS patients that suggest the presence of in vivo regulatory mechanisms for the action of vitamin A on the immune system.

The effect of vitamin a supplementation on biochemical parameters in multiple sclerosis patients (2013) NEW
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3745746/
... The current study aimed to investigate the possible complications and find solutions to minimize the adverse effects. ...
CRP level in vitamin A group was 1.3 mg/L more than those of the placebo group after intervention (P=0.011).

about CRP https://www.mayoclinic.org/tests-proced ... c-20385228
(it's all about the balancing act. look into the CRP-lowering possibilities of vit C and magnesium for example, and med diet esp veg and fruit - ie food vit c, mag, vit a and more!)

The Evidence for a Beneficial Role of Vitamin A in Multiple Sclerosis (2014)
https://link.springer.com/article/10.10 ... 014-0148-4
... The present review discusses the beneficial effects that vitamin A might have for controlling MS, although it must be clearly stated that, at the present time, there is no clear indication for using vitamin A as a treatment for MS. However, the results from the present review should encourage clinical trials with vitamin supplementation as a potential treatment or as an add-on option. Vitamin A acts in synergy with vitamin D, and the immunological homeostasis ensured by these vitamins should not be unbalanced in favour of only one of them.

Vitamin A is not associated with exacerbations in multiple sclerosis (2014)
https://www.sciencedirect.com/science/a ... 4813000771
...Results
Mean vitamin A levels were lower in patients (2.16 μmol/l) than in controls (2.44 μmol/l) but with borderline significance (p=0.05). I
...
... Conclusion
We did not find evidence for a role for vitamin A in the disease course of RRMS. We did find an association between vitamin A and D levels in the RRMS patients, possibly explained by dietary products that contain both fat-soluble vitamins.

Impact of Vitamin A supplementation on disease progression in patients with multiple sclerosis (2015)
http://www.aimjournal.ir/Article/855
"... The treated group received 25000 IU/d retinyl palmitate for six month followed by 10000 IU/d retinyl palmitate for another six month. Results for the expanded disability status scale (EDSS) and multiple sclerosis functional composite (MSFC) were recorded at the beginning and the end of the study. ... CONCLUSION: Vitamin A improved total MSFC score in RRMS patients, but it did not change EDSS, relapse rate and brain active lesions."

(i'm having trouble finding the baseline and post treatment serum vit A levels in this ^ one... )

Retinoic acid enhances the levels of IL-10 in TLR-stimulated B cells from patients with relapsing–remitting multiple sclerosis (2015) NEW
https://www.sciencedirect.com/science/a ... 2814009801

Highlights
•Retinoic acid enhances the levels of IL-10 secreted by B cells from MS patients.
•IFN-β and retinoic acid display the same ability to enhance IL-10-secretion.
•Retinoic acid still has a beneficial effect after treatment of MS patients.

Molecular Mechanisms of the Action of Vitamin A in Th17/Treg Axis in Multiple Sclerosis (2015) NEW
https://link.springer.com/article/10.10 ... 015-0643-1

... Evidence suggests that vitamin A and its active metabolites (all-trans-retinoic acid and 9-cis-retinoic acid) modulate the imbalance of Th17 and Treg cells through multiple molecular pathways and can be considered as a promising target in the prevention and treatment of MS.

The Molecular Mechanisms of Vitamin A Deficiency in Multiple Sclerosis (2016)
https://link.springer.com/article/10.10 ... 016-0781-0

There is evidence that the level of plasma vitamin A (retinol) is lower in MS patients and that there is a negative correlation between serum vitamin A and disease development (Besler et al. 2002; Royal et al. 2002) ...Vitamin A may ameliorate MS pathogenesis through numerous mechanisms including a reduction in inflammatory processes by re-establishing the balance between pathogenic (Th1, Th17, Th9) and immunoprotective cells (Th2, Tregs), modulating B cell and dendritic cell function as well as increasing tolerance of autoimmunity and regeneration in the CNS. Thus, the results from the current review suggest that vitamin A can be considered as a potential treatment in MS disease management.

Effect of vitamin A supplementation on fatigue and depression in multiple sclerosis patients: a double-blind placebo-controlled clinical trial (2016)
https://ijaai.tums.ac.ir/index.php/ijaa ... e/view/692

"... The treatment group was administered 25000 IU/d retinyl palmitate (RP) for 6 months followed by 10000 IU/d RP for another 6 months. ... The results showed significant improvement in the treatment group for fatigue (p=0.004) and depression (p=0.01). ... "

Serum retinol levels are associated with brain volume loss in patients with multiple sclerosis (2017)
https://journals.sagepub.com/doi/full/1 ... 7317729688

" ... Conclusions
Our study shows that lower serum retinol levels are associated with greater longitudinal brain volume loss (BVL) and that serum retinol binding protein (RBP) and (sic) can be a predictor of BVL."

Retinoic Acid, Leaky Gut, and Autoimmune Diseases (2018) NEW
https://www.mdpi.com/2072-6643/10/8/1016/htm

"Retinoic acid (RA) can increase the relative abundance of Lactobacillus spp. in the gut. Interestingly, RA has also been shown to strengthen the barrier function of epithelial cells in vitro and in the absence of probiotic bacteria. These reports bring up an interesting question of whether RA exerts protective effects on the intestinal barrier directly or through regulating the microbiota colonization. In this review, we will discuss the roles of RA in immunomodulation, recent literature on the involvement of a leaky gut in different autoimmune diseases, and how RA shapes the outcomes of these diseases."

The effect of retinyl-palmitate on the level of pro and anti-inflammatory cytokines in multiple sclerosis patients: A randomized double blind clinical trial (2019)
https://www.sciencedirect.com/science/a ... 6719300034

"Patients and methods
Thirty-six relapsing-remitting MS patients were enrolled in this double-blind randomized clinical trial. Participants received one capsule of 25,000 IU RP or a placebo per day for six months. ...
Conclusion
Unexpectedly, this study found no significant changes in cytokine levels after six months of RP supplementation in MS patients. ...
These findings are not in agreement with the results of some studies evaluating cytokine levels in MS patients in response to vitamin A. ...
This contradiction may be due to the form of vitamin A supplementation, retinyl-palmitate, in the current study [9,22]. Other studies that reported significant changes in the production of anti- and pro-inflammatory cytokines in cell cultures or animal models in response to vitamin A have used RA, the active form of vitamin A [9,22,23]. Because of the possible harmful effects of RA on humans [24,25], the RP form of vitamin A was used in this study. When RP is converted to RA in the body, many regulatory mechanisms are involved that inhibit the peak of RA concentration in the circulatory system. So, The effect of RP cannot be as was hypothesized for RA [19,26]. It is likely that a different dose or period from that used in this study is needed to obtain results that are similar to direct intervention with RA. ..."

A systematic review and meta-analysis of randomized controlled trials to evaluating the trend of cytokines to vitamin A supplementation in autoimmune diseases (2019)
https://pubmed.ncbi.nlm.nih.gov/30473441/

" ... Results: Fixed effect analysis of the WMD (95% CI) of the changes in gene expression showed that gene expression of the inflammatory (IL-17, IFN-γ and T-bet) and anti-inflammatory (TGF-β and FOXP3) cytokines significantly decreased and increased due to vitamin A supplementation in patients with autoimmune (Multiple sclerosis and atherosclerosis) diseases.

Conclusions: Vitamin A supplementation effects on gene expression and may improve serum level of cytokines and clinical signs of autoimmune disease but there is no adequate evidence."

Nutritional supplementation of vitamin A and health-related outcomes in patients with multiple sclerosis
A protocol for a systematic review and meta-analysis of randomized clinical trials (2019)

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6636979/

"... Results:
In this study, we hope to find a considerable number of articles presenting evidence about the effectiveness of vitamin A supplementation in patients with MS. ..."

Advances and challenges in retinoid delivery systems in regenerative and therapeutic medicine (2020) NEW
fft: https://www.nature.com/articles/s41467-020-18042-2

"... In this Review, we discuss advances in preclinical and clinical tests regarding retinoid formulations, specifically the ones based in natural retinoids, evaluated in the context of regenerative medicine, brain, cancer, skin, and immune diseases. Advantages and limitations of retinoid formulations, as well as prospects to push the field forward, will be presented."
https://www.who.int/news-room/q-a-detail/q-a-coronaviruses

take control of your own health.
pursue optimal self care, with or without a diagnosis.

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jimmylegs
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Re: vitamin A

Post by jimmylegs » Mon Nov 16, 2020 4:27 am

re research compilation post above, newly added studies (Nov 16 and 17, 20) are flagged NEW
https://www.who.int/news-room/q-a-detail/q-a-coronaviruses

take control of your own health.
pursue optimal self care, with or without a diagnosis.

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