Increasing Brain-Derived Neurotrophic Factor to Improve Memory
By Dr. Ayo Bankole
Age related cognitive decline is one of the most common complaints in primary care and has grown more prevalent as the size of the aging population increases. By 2040 adults 65 and older are expected to grow by 6%, making up 22% of the population. Although cognitive decline is a sign of aging and dementia, it can occur in the absent of both and instead be due to chronic emotional stress and elevated cortisol, viral infections affecting the brain like COVID-19, gluten intolerance, mold, and hormonal imbalances for example. No matter the cause, preserving brain function and memory is best done by addressing the underlying cause and early treatment. A healthy memory, especially one that we can preserve into aging is one of the most valuable attributes of health and quality of life we can have. Without it we lose our confidence, wit, communication, our ability to experience joy, appreciation and ultimately, we can lose ourselves.
Cognitive decline is associated with a decrease in brain cell activity, decreased cell signaling and cell to cell communication. Most notable, cognitive decline is characterized by a decrease in neurogenesis. Neuroscientists describe neurogenesis as the growth of neurons (brain cells), and the communication pathways that connect them, known as synapses. Neurogenesis is the cornerstone of dynamic memory and healthy brain aging. Boosting Brain-derived neurotrophic factor (BDNF) has been shown to be effective in increasing both neurogenesis and healthy memory in human adults.
Neurogenesis and Brain-Derived Neurotrophic Factor
BDNF is a protein that in humans is encoded by the BDNF gene. It functions as a neurotrophic factor, promoting the development, function and survival of neurons.(1) BDNF also prevents the activation of programmed cell death or apoptosis in neurons.(1) Neurotrophins like BDNF are also important in neuroplasticity(2), the brain’s ability to adapt, modify and change based on stimuli, circumstances or trauma. Essentially, BDNF influences neuroplasticity, protects and repairs our brain cells, and promotes neurogenesis.(3) High levels of BDNF are associated with improved cognitive function. Three factors that can be stacked together to increase BDNF are high intensity exercise, gardening, and the use of Synapsin.
Exercise and BDNF
Studies have shown increases in neurotrophic factors such as BDNF are enhanced by higher aerobic activity.(4) For example, individuals who participated in a six-week study performed twenty minutes of high intensity interval training three-times weekly. Individuals who gained the largest adaptation to aerobic activity had the greatest increases in both BDNF and IGF-1 (insulin-like growth factor-1). (5) IGF-1 is thought to increase BDNF levels as well.(5)
Synapsin and Neurocognition
A novel natural agent available to improve neurocognition is Synapsin. Synapsin contains RG3, a component of the ginseng root, along with nicotinamide riboside (NR) a precursor to NAD+. The RG3 component is known to enhance BDNF and is therefore neuroprotective. It also functions to shut off inflammation in the brain from microglial cells. Microglial cells function as the brain’s immune cells. They are known to upregulate chronic inflammation in the brain and have no inherent “off switch.” Synapsin turns down neuroinflammation induced from microglial cells, rather the inflammation is triggered by a traumatic brain injury, an infection, toxic metals, or stress. Synapsin is administered as a nasal spray, twice daily. Although it is a natural compound, it is available by prescription only. It can work as fast as a month, is safe and typically causes no side effects other than temporary nasal irritation.
Gardening and BDNF
Forty-one seniors averaging 76.6 years of age had their brain-derived neurotrophic factor measured before and after performing low to moderate intensity gardening that included raking, watering, planting and digging.(7) The researchers recorded an average 8.4% increase in BDNF. (6) Exposure to green space has long been associated with improvements in health parameters such as cardiometabolic, cognition and stress. It may be that gardening, for one, combines the benefits of exercise and green space together as other outdoor activities can. Gardening’s impact on BDNF may have some ancient relationship with humans age old symbiotic relationship found in cultivating the earth that has gone on for tens of thousands of years. Or perhaps related to the satisfaction we gain from seeing the fruits of our labor come forth to enjoy and share with others. No matter how, gardening is an activity that along with its’ many benefits, can increase BDNF.
Summary
Some causes of cognitive decline include dementia, aging, and other factors such as chronic emotional stress and elevated cortisol, viral infections affecting the brain like COVID-19, gluten intolerance, mold, and hormonal imbalances. Preserving our memory and brain function is easily one of the most important factors related to quality of life as we age. No matter what the cause of cognitive decline is, it is best treated early and while addressing the underlying cause. Neurogenesis is the cornerstone of dynamic memory and healthy brain aging and can be enhanced with BDNF. Exercise, gardening, and Synapsin are three strategies that can be stacked together to increase BDNF levels in aim of supporting healthy memory and brain function.
References:
- Kowiański P, Lietzau G, Czuba E, et al. BDNF: A Key Factor with Multipotent Impact on Brain Signaling and Synaptic Plasticity. Cell Mol Neurobiol. 2018:38(3):579-593.
- Baj G, Carlin D, Gardossi L, Tongiorgi E. Toward a unified biological hypothesis for the BDNF Val66Met-associated memory deficits in humans: a model of impaired dendritic mRNA trafficking. Front Neurosci. 2013:7:188.)
- [Vaynman S, Ying Z, Gomez-Pinilla F. Hippocampal BDNF mediates the efficacy of exercise on synaptic plasticity and cognition. Eur J Neurosci. 2004;20(10):2580-2590.
- Cotman CW, Berchtold NC, Christie LA. Exercise builds brain health: key roles of growth factor cascades and inflammation. Trends Neurosci. 2007;30(9):464-472.)
- Heisz J, Clark I, Bonin K, et al. The effects of physical exercise and cognitive training on memory and neurotrophic factors. J Cogn Neurosci. 2017;29(11):1895-1907.
- (Olsen RK, Moses SN, Riggs L, Ryan JD. The hippocampus supports multiple cognitive processes through relational binding and comparison. Front Hum Neurosci. 2012;6:146.)
- Park S-A, Lee A-Y, Park H-G, Lee W-L. Benefits of gardening activities for cognitive function according to measurement of brain nerve growth factor levels. Int J Environ Res Public Health. 2019;16(5):760.
