Dr. Weeks; Comment: Alzheimer’s is a disease which is driven by inflammation. The brain and all neurological tissue is fatty tissue and comprised of 100x more omega 6 fatty acids than omega 3 fatty acids. There are many naturally occurring compounds which are anti-neurodegenerative. One such compound is thymoquinol recently found in a chinese plant, S. Chinensis.
Conclusions This is the first scientific report on isolation and identi- fication of neuroprotective compounds from the rattan stems of S. chinensis. Seven new compounds were iden- tified, which include three new lignans (1 – 3) and four new thymoquinol glycosides (4 – 7). Neuroprotective activity was screened by the MTT assay. As a result, dibenzocyclooctadiene lignans 2 and 3 showed protec- tive effects on the PC12 cells in a dose-dependent man- ner (Table5) at the tested concentration. Thus, dibenzocyclooctadiene lignans appear to be the anti- neurodegenerative constituents of the rattan stems of S. chinensis. (SOURCE)
Lithium is neuroprotective in low doses (20mg).
Closer to home and available now, SOUL is a delicious drink rich in thymoquinol and made from anti-inflammatory seeds rich in omega 6 fatty acids.
Neuroprotective effect of natural products against Alzheimer’s disease.
Nature has gifted mankind with a plethora of flora-bearing fruits, vegetables and nuts. The diverse array of bioactive nutrients present in these natural products plays a pivotal role in prevention and cure of various neurodegenerative diseases, such as Alzheimer’s disease (AD), Parkinson’s disease and other neuronal dysfunctions. Accumulated evidence suggests that naturally occurring phyto-compounds, such as polyphenolic antioxidants found in fruits, vegetables, herbs and nuts, may potentially hinder neurodegeneration, and improve memory and cognitive function. Nuts such as walnut have also demonstrated neuroprotective effect against AD. The molecular mechanisms behind the curative effects rely mainly on the action of phytonutrients on distinct signalling pathways associated with protein folding and neuroinflammation. The neuroprotective effects of various naturally occurring compounds in AD is evaluating in this review.
Review question/objective: The objective of this review is to explore the existing literature related to phytochemicals and cognitive/behavioral function in patients with Alzheimer’s disease, to examine and conceptually map the evidence, and to identify any gaps.
The question of this review is: what is the evidence on phytochemicals and cognitive/behavioral function in patients with Alzheimer’s disease?
Alzheimer’s disease (AD) is a neurodegenerative disease characterized by progressive deterioration in cognitive and behavioral function.1-3 In Western countries, AD accounts for more than half of all dementia cases.2,4,5 Autopsy is considered necessary for definitive diagnosis, however clinical diagnosis is often made through measurements of physical and cognitive function such as the Mini Mental Status Examination (MMSE).6 It is estimated that there are currently over 25 million people living with AD worldwide and that this number will increase to over 100 million by 2050,2-8 with roughly one in eighty-five people throughout the world living with AD.8 Approximately US$100 billion is spent annually to provide care for AD patients including adult day programs, residential care communities, home health agencies hospice and nursing homes.7 Risk factors for AD include age, nutrition and exposure to toxins in our food and environment.3,4
The symptoms of AD include impaired cognitive, visuospatial and language abilities as well as changes in behavior and personality.9 These are manifestations of the pathophysiologic changes occurring within the body due to toxins present in our food and environment.2,3,5 Exposure to toxins induces a stress response throughout the body’s tissues which results in mitochondrial dysfunction, protein misfolding and aggregation as well as synapse loss.5,10 As protein clusters form, they inhibit the body’s abilities for cellular signalling and neuronal function, leading to eventual neuron loss through apoptosis.10 Physical changes can be seen in MRI scans showing medial temporal lobe (MTL) atrophy as well as in positron emission tomography (PET) scans showing hypoperfusion in temporoparietal areas.11 Recent research has focused on dietary factors and their ability to modify or inhibit inflammatory pathways to slow or halt disease progression.7
Although interest in holistic treatments is not entirely new to the medical world, the mechanism of action of these therapies has not been well understood, resulting in more recent research into therapies such as herbal medicine and phytochemicals for AD.12,13 Phytochemicals or the non-nutrient plant compounds in fruits, vegetables other plant foods show promise in the treatment of many chronic conditions.14 Studies focusing on plant phytochemicals have shown that they act as antioxidants by scavenging free radicals that have been induced through stress.2,3,5,15 This leads to neuronal cell regeneration, neuroprotection and neurorescue activities in the brain that support improved neuronal survival, differentiation, long-term potentiation and memory enhancement.5,10,16 Regular intake of phytochemicals through a diet high in fruits and vegetables has been shown to improve mental and physical function, increase neuron cell survival and boost the antioxidant system.2,3,5,7,16,17
The brain requires a large, constant source of energy which is provided by nutrients found in our diets, making personal food choices important.7,18 A diet high in saturated fats, red meat and other processed meats has been linked to the development of iron-induced free radicals which contribute to insoluble deposits in the brain typically seen in AD.19 Conversely, diets consisting of mostly fruits, vegetables and nuts provide a natural source of bioactive phytochemicals that are thought to play a pivotal role in the prevention and slowed progression of chronic conditions.7,17 Fatty acids, sterols, alkaloids, flavonoids, glycosides, saponins, tannins and terpenes are some of the phytochemicals known to be found in these food sources.13,14 Researchers are beginning to understand their mode of action, however, it is unclear whether their benefit is due to a combined action as a whole food or if it could be replicated with supplementation of individual phytochemicals.14
There are currently several pharmaceutical options marketed for the treatment of AD symptoms, such as cholinergic drugs, cholinesterase inhibitors, stimulants and vasodilators.13 However, they have only provided modest benefits to patients suffering from the disease.2 This has led to an interest in alternative therapies within the Western medical community, but there is still limited data available in humans regarding the effects of phytochemicals on the progression of AD.5 Both in vitro and in vivo studies representing the effects of supplementation with phytochemicals on the brain function of animal models who have been modified to represent brains affected with AD are more widely available.2,3,5,7,16 These studies have cited significant reversal of age related deficits in neuronal and behavior parameters as well as decreased neuron damage and oxidative stress.5,7,17 Other studies, also using rat models, have shown improved locomotor activity and neuronal protection mechanisms.5,7 Most interestingly, one study even showed that certain phytochemicals found in berberine can cross the blood brain barrier in rats with positive effects on brain function.16 Considering the lack of proven treatment for AD, a review of dietary changes to include phytochemicals is of extreme importance.
There are systematic reviews investigating diet and vitamin consumption in the setting of AD. However, the existing systematic reviews focus on interventions to increase food consumption, increase vitamin/mineral supplementation and dietary interventions in older dementia patients or people who have not yet been diagnosed with AD.20-23 This review does not aim to find strategies to increase food consumption in late stage AD patients or to review literature relating to vitamin deficiency. This review aims to explore the topic of phytochemicals and the progression of AD. A preliminary search for systematic and scoping reviews has been conducted and none have been identified. The following sources were searched for scoping reviews: JBI Database of Systematic Reviews and Implementation Reports, PROSPERO, Campbell Systematic Reviews and Database of Abstracts of Reviews and Effects.
A review of this subject is vital to the future of healthcare as around the world, the population is aging and millions of people are living with a diagnosis of AD.8 Current pharmaceutical treatment options are not providing sufficient relief from the burden of disease and current projections show the number of people living with AD continuously growing until at least 2050.1 Nurses, providers and caregivers everywhere will need to understand how to best care for these patients and what options they have for symptom management. As AD patients develop obvious deficits, their disease process is already advanced and even the most proven medical therapies will be less effective.11 This creates a sense of urgency to find an intervention that could be applied easily in the early stages of disease, such as a dietary intervention with phytochemicals. The purpose of this scoping review is therefore to find what is known about phytochemicals and cognitive/behavioral function in patients with AD. The JBI methodology for scoping reviews will be used for this review.24
This review is to contribute towards the degree award of Doctorate of Nursing Practice (DNP) from University of Mississippi Medical Center School of Nursing for DRB.
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Alzheimer’s disease; Alzheimer’s; dementia; diet; phytochemicals