The term “neurodegenerative diseases” is a generic term that includes a series of diseases of the nervous system involving neurons in which primary degeneration in specific anatomical regions is observed. More specifically, there is a disorder in the structure and function of neurons in distinct regions of the nervous system and affects specific cell populations.
Neurodegenerative diseases are closely related to age and are largely incurable conditions that weaken the patient, cause disability, lead to progressive degeneration and / or death of nerve cells. This development causes problems in movement (ataxia) or in mental function (dementia).
ND do not include myelin elytron ailments and conditions such as neoplasms, trauma, ischemia and infections where neuronal degeneration is secondary.
What are neurons?
Neurons are structural units of the nervous system that includes the brain and the spinal cord. As a rule, neurons do not reproduce and are not renewed, so if they are harmed or die they can not be replaced by the body.
The proportion of the world population affected by ND is steadily rising, perhaps due to the increase in life expectancy and population growth. These are diseases that affect mainly elderly people. Among these ND, dementia of various types presents the highest rates of morbidity, followed by Alzheimer’s disease and related disorders affecting up to 7 million people in Europe. It is noteworthy that this number is expected to double every 20 years as the population ages. At present, the cost for the care of people with dementia across Europe is about € 130 billion a year, highlighting age-related neurodegenerative diseases as one of the top medical and social challenges facing our society.
It is striking that ND, apart from the older age, can also occur at the age of 30 or 40, although these cases are rather rare. It may occur rarely at younger ages, especially when there are specific aggravating genetic or environmental factors. For example, in Alzheimer’s disease, mutations in 3 genes, APP, PSEN1 and PSEN2 cause the disease between the ages of 30-60 years. Increased expression of the APP gene is also observed in individuals with Down syndrome, due to an additional copy on chromosome 21, these individuals usually show the disease in their fifth decade of life.
Which are the most common NDs?
- Alzheimer’s disease (AD) and other forms of dementia
- Parkinson’s disease (PD) and PD-related disorders
- Prion Diseases
- Motor Neuron Disease (MND)
- Huntington Disease (HD)
- Spinocerebellar Ataxia (SCA)
- Spinal Muscular Atrophy (SMA)
- Myasthenia Gravis
- Multiple Sclerosis
- Amyotrophic Lateral Sclerosis
Classical classification of neurodegenerative diseases based on the main clinical picture and the topography of the dominant lesions,
- Cerebral cortex: Dementia (AD), Without Dementia
Basic ganglia: promotor (PD), hyperkinetic (HD)
- Cerebellum and its connections: cerebellum – cortex atrophy, cerebellum-pontile atrophy (multiple structures in brain’s cortex and cerebellum), Friedreich ataxia. Many of the diseases of this category can not get classified i.e Machado-Joseph disease (motor neurons, substantia-nigra cerebellorubral-system)
- Spine: ALS, spinal muscular atrophy
What is the common feature of most neurodegenerative diseases?
A common feature of many neurodegenerative diseases is the disorder in protein folding and the accumulation of these leading to the formation of endothelial inclusions or plaques
It is believed that proteins with a folding disorder have toxic effects and induce degeneration of neurons. In particular, neurons with intense metabolic activity, increased oxygen consumption and neurotransmitter synthesis are more susceptible to changes that lead to protein accumulation. In particular, oxidative radicals (free radicals) and oxidative derivatives released during cellular metabolism and not eliminated due to the lack of antioxidant molecules lead to protein lesions.
Factors contributing to the emergence of ND
Genetic and environmental factors play an important role in the emergence of neurodegenerative diseases.
Epidemiological studies have confirmed that environmental toxins are one of the most important factors contributing to the development of neurodegenerative disorders (eg excessive exposure to pesticides, heavy metals, etc.)
Several scientific groups have also discovered that ND contributes to the gene response, and in particular, a large number of genes involved in these conditions have been reported (e.g., a mutation of the hGDH2 protein has accelerated the onset of Parkinson’s disease and that one mutation of the SLC25 gene causes ataxia)
What are these lifestyle factors that facilitate the occurrence of a ND?
A study in 7 countries (2009) has shown that factors such as smoking, hypertension and increased total cholesterol in the middle age are associated with increased risk for dementia.
An analysis published in Lancet2 in 2011 shows that about 50% of cases of Alzheimer’s disease globally are factors such as diabetes mellitus, middle-age hypertension, middle-age obesity, smoking, depression, mental Inactivity or low educational level and lack of physical activity.
What are the lifestyle factors that can protect us from a ND?
Dieting can significantly help in prevention, as demonstrated by a recent analysis of the Caerphilly Prospective Study (2013) in Wales. According to this study, daily consumption of more than three portions of fruit and vegetables reduces the risk of dementia by 20% in 30 years. If this change is combined with other lifestyle changes such as alcohol abstinence and systematic, mild physical exercise, the benefits are far greater
Also the Mediterranean, and especially the Cretan Diet, which is characterized by high intake of vegetables, legumes, nuts and seeds, fruits, cereals, moderate fish intake, high intake of beneficial polyunsaturated fatty acids, low intake of saturated fatty acids, low intake of meat and dairy products and limited consumption of alcohol, mainly in the form of wine, has been associated with a reduced risk of cardiovascular disease, several types of cancer and overall mortality, but also in reducing the risk for the onset of Alzheimer’s disease. It is noteworthy that the Mediterranean Diet may have significant benefits, even when Alzheimer’s disease is settled and its symptoms have begun.
The role of Functional Medicine in ND
Functional Medicine has as a rule, as in all diseases and for ND, first of all the prevention. Even though the news that neurodegenerative diseases are increasing is ominous, the news is so optimistic about the prevention of these conditions. As we know from the Greek medical tradition, it is more important to receive than to cure, because treating it when the disease has occurred is like digging to find water when you have already thirsty. Even more important than diagnosis, it is therefore not necessary to diagnose!
If, however, the onset of the disease is not avoided, it is important that the diagnosis be made as early as possible so that there is room for reversing even partial or even slowing progression of the disease. Even when there are genes predisposing to such a disease, lifestyle factors can modify gene expression and thus suppress or reverse the mechanisms that lead to inflammation and degeneration. Thus, the onset of the disease can be avoided or, in the worst of cases, delayed significantly.
The specialized examinations available to Functional Medicine are able to read cellular function and understand the mechanism of disease so targeted to support the healthy cell or even the cell that is already diseased;thus contributing to the treatment of neurodegenerative diseases based mainly on the application of antioxidant, anti-inflammatory and protective vascular or other biological mechanisms, and not chemotherapy.
In this way, Operational Medicine has proven not to address the causes of pathogenicity at its root, but artificially attempts to overturn the final visible effect and symptom.