Tag Archives: BDNF

Depressed due to suboptimal BDNF? Try a little sunshine!

BDNFSome time ago I wrote a blog on sun exposure and depression, emphasizing the importance of a protein called brain derived neurotropic factor (BDNF). This is an update.

BDNF is a factor in nerve growth and maturation, and is essential in synapse formation and plasticity. A lack of of it is implicated in psychiatric disorders such as schizophrenia, intellectual disability, autism and depression. Interestingly, it has been shown that unless there is sufficient BDNF in the brain, conventional antidepressants do not work very well,[1] and when BDNF is infused directly into the brains of rodents, it produces an antidepressant effect.[2]

It has also been shown that BDNF has a seasonal variation in concentration correlating with the amount of ambient sun; it increases in the spring and summer and decreases in fall and winter. [3]  The authors of this research described the importance of their findings thusly: “This finding is important for our understanding of those factors regulating BDNF expression and may provide novel avenues to understand seasonal dependent changes in behavior and illness such as depression.”

BDNF has been shown to increase significantly after bright light exposure,[4] and in what we would consider to be a remarkably important study, both light exposure and treadmill exercise increased its expression of
 in rats,[5] or as the researchers showed, exercise and/or bright light promoted neurogenesis (new nerve cell growth) in the adult rat brain. How important is this finding for adults who are worried about cognitive decline? We are actually seeing an example of new brain cells being built by bright light and exercise. What a wonderful way to help prevent Alzheimer’s disease and maintain mental sharpness into old age! Don’t forget your (safe) sunlight!

[1] Björkholma C, Monteggiab, L. BDNF — a key transducer of antidepressant effects. Neuropharmacology. 2016 March ; 102: 72–79.

[2] Siuciak JA, Lewis DR, Wiegand SJ, Lindsay RM. Antidepressant-like effect of brain-derived neurotrophic factor (BDNF). Pharmacol. Biochem. Behav. 1997; 56(1):131–137.

[3] Molendijk ML, Haffmans JP, Bus BA, Spinhoven P, Penninx BW, Prickaerts J, Oude Voshaar RC, Elzinga BM. Serum BDNF concentrations show strong seasonal variation and correlations with the amount of ambient sun. PLoS One. 2012;7(11):e48046.

[4] Tirassa P1, Iannitelli A, Sornelli F, Cirulli F, Mazza M, Calza A, Alleva E, Branchi I, Aloe L, Bersani G, Pacitti F. Daily serum and salivary BDNF levels correlate with morning-evening personality type in women and are affected by light therapy. Riv Psichiatr. 2012 Nov-Dec;47(6):527-34.

[5] Kwon SJ, Park J, Park SY, Song KS, Jung ST, Jung SB, Park IR, Choi WS, Kwon SO. Low-intensity treadmill exercise and/or bright light promote neurogenesis in adult rat brain. Neural Regen Res. 2013 Apr 5;8(10):922-9.

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New and interesting research on cancer and sun exposure.

By Marc Sorenson, EdD, for sun exposure…

A new research paper on sun exposure and cancer has some interesting observations and some errors.[1] It is entitled, Does Sunlight protect us from cancer? Here is the abstract of the article, verbatim.

“The Ultraviolet (UV) radiation contained in sunlight is a powerful mutagen and immune suppressant which partly explains why exposure to solar UV is the biggest risk factor for the development of cutaneous tumors. Evidence is building that sunlight may be protective against some internal malignancies. Because patients with these tumors are often vitamin D deficient, this has led some to propose that vitamin D supplementation will be beneficial in the treatment of these cancers. However, the results from already completed trials have been disappointing which has given weight to the argument that there must be something else about sunlight that explains its cancer-protecting properties.”

The first sentence, of course, is false. The idea, that sun exposure is the biggest risk factor for skin cancer, is erroneous. We have presented materials many times, proving that melanoma is not caused by sun exposure, and that sun exposure is protective against that disease. And as regards common skin cancers, we have shown that high-fat nutrition, lack of antioxidants, meat consumption and alcohol intake are all risk factors. Search the blogs on this site to read the different articles.

The statement is correct, of course, that sunlight is protective against many internal cancers. Dr. Bill Grant and I are finishing our book, Embrace the Sun, where we present nearly all of the research on the protective influence of sun exposure against cancer.

The statement that vitamin D research has been disappointing is both true and false. Randomized controlled studies (RCTs) have shown the vitamin D supplements do have a protective effect against internal cancers, contrary to the statement by the researchers.

Finally, let’s look at the statement that there is something beyond vitamin D that explains the cancer-protecting properties of sun exposure. That is partially true. Beyond vitamin D, the sun causes the production of nitric oxide, serotonin, endorphin and BDNF, all of which are vital to human health, and may have their own cancer-protective properties.

The bottom line? Eat correctly (avoid junk), REGULARLY soak up some sun around midday and get plenty of exercise. That advice will be a boon to your health in myriad ways.

[1]Marshall JE, Byrne SN. Does sunlight protect us from cancer? Photochem Photobiol Sci. 2017 Jan 19. doi: 10.1039/c6pp00332j. [Epub ahead of print] 

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Protect your Brain with Sun Exposure and Exercise.

By Marc Sorenson, EdD.  Sunlight Institute

Part of our brain function is influenced by a naturally produced protein called Brain-Derived Neurotropic Factor (BDNF), part of a cascade of proteins that promotes neuron growth and prevents neuron death.[1] Research shows that BDNF has an influence on processes and behaviors such as depression and brain plasticity and has a seasonal variation in concentration that correlates with the amount of ambient sun;[2] BDNF increases in the spring and summer and decreases in fall and winter. The authors of this research summed up their findings thusly: “This finding is important for our understanding of those factors that regulate BDNF expression and may provide novel avenues to understand seasonal dependent changes in behavior and illness such as depression.”

Correct levels of BDNF, however, have many other important and positive effects in the body,[3] including promoting of long-term memory, regulation of mood and perception of pain, reduction of Alzheimer’s disease and Huntington’s disease, and control of epilepsy, depression, anxiety, bipolar disorders, schizophrenia and addiction. In addition, it has positive effects on type-two diabetes, cardiovascular disease and colorectal cancer.

BDNF has been shown to increase significantly after bright light exposure,[4] and in what I would consider to be a remarkably important study, both light exposure and treadmill exercise increased the expression of BDNF in rats,[5] or as the researchers showed, exercise and/or bright light promoted neurogenesis (new nerve cell growth) in the adult rat brain. How important is this finding for adults who are worried about cognitive decline? We are actually seeing an example of new brain cells being built by bright light and exercise. But the researchers were not through with their recommendations. They stated this in their summary: “In view of these findings, we propose that moderate exercise or exposure to sun during childhood can be beneficial for neural development.”

Other research has also indicated that physical activity is positively associated with BDNF.[6]

Add one more natural chemical that is inversely associated with depression and directly associated with sun exposure. We now have vitamin D, serotonin, endorphins, dopamine and BDNF.

Want to maintain your IQ and other brain functions? Would you rather not take the chance of suffering from Alzheimer’s? Embrace the sun, and move your body! Be careful not to burn. And remember that the use of sunscreens may negate many of the sun’s wholesome effects.

[1] http://scicurious.scientopia.org/2010/12/13/bdnf-and-depression/

[2] Molendijk ML, Haffmans JP, Bus BA, Spinhoven P, Penninx BW, Prickaerts J, Oude Voshaar RC, Elzinga BM. Serum BDNF concentrations show strong seasonal variation and correlations with the amount of ambient sun. PLoS One. 2012;7(11):e48046.

[3] Juzeniene A. Beneficial effects of UV‐radiation unrelated to Vitamin D. Presentation at International Symposium Biological Effects of Light June 11 ‐ 12, 2015 Homborg, Germany.

[4] Tirassa P, Iannitelli A, Sornelli F, Cirulli F, Mazza M, Calza A, Alleva E, Branchi I, Aloe L, Bersani G, Pacitti F. Daily serum and salivary BDNF levels correlate with morning-evening personality type in women and are affected by light therapy. Riv Psichiatr. 2012 Nov-Dec;47(6):527-34.

[5] Kwon SJ, Park J, Park SY, Song KS, Jung ST, Jung SB, Park IR, Choi WS, Kwon SO. Low-intensity treadmill exercise and/or bright light promote neurogenesis in adult rat brain. Neural Regen Res. 2013 Apr 5;8(10):922-9.

[6] Gomes da Silva S, Arida RM. Physical activity and brain development. Expert Rev Neurother. 2015 Aug 9:1-11.

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