Alzheimer’s Disease (AD) is the most common neurodegenerative disease in the world and the main cause of functional dependence, institutionalization and death among the elderly population in Brazil.
With the increase in life expectancy, it is estimated that every 33 seconds there is a new case of the disease. According to the World Health Organization (WHO), there are already 35.6 million people with AD in the world, and this number is expected to double by 2030 and triple by 2050. Therefore, it is essential that we make progress in researching the most promising therapeutic alternatives for the disease.
One of the strands currently explored is medicinal Cannabis. In a review carried out in the Pubmed, Cochrane, Biblioteca Virtual em Saúde [Virtual Health Library] (BVS) and Scielo, Sousa and Marques databases, they conclude that medicinal Cannabis is a promising therapy to aid in the treatment of Alzheimer’s Disease, as it has few side effects and act directly on the main pathophysiological mechanisms of the disease (regulation of neurotransmitters, formation and deposition of β amyloid plaques, toxicity and neuronal death). The work was presented at the VI International Congress on Human Aging, in 2019.
>> Read on: Findings on the use of Cannabis in the Alzheimer’s Disease: a literature review
What is already known about medicinal Cannabis use in Alzheimer’s
In 2016, a study was carried out with 11 participants with AD, all with behavioral and psychological symptoms related to dementia. Patients were treated with Cannabis oil for 4 weeks and the results were promising: a significant reduction in the Clinical Global Impression score, less caregiver stress and improvement in neuropsychological domains such as delusions, insomnia, apathy and irritability were observed. Apparently, this occurred due to the activation of the Endocannabinoid System and, consequently, to the reduction of neuronal death induced by deposition of β amyloid plaques.
>> Check here the study Safety and Efficacy of Medical Cannabis Oil for Behavioral and Psychological Symptoms of Dementia: An-Open Label, Add-On, Pilot Study
Another 2014 study of Alzheimer’s and medical Cannabis in mice, improvement in symptoms of memory loss, social recognition and learningwas seen in the animals. Alzheimer’s mice were 1 year old and were treated with 50 mg/kg/day of CDB for 3 weeks. The reduction in symptoms was accompanied by a decrease in beta amyloid protein deposits in the hippocampus of the animals.
>> See Long-term cannabidiol treatment prevents the development of social recognition memory deficits in Alzheimer’s disease transgenic mice
In another 2020 study of Alzheimer’s and medical Cannabis in mice, improvement in symptoms of memory loss, social recognition and learning was seen in the animals. Alzheimer’s mice were 1 year old and were treated with 50 mg/kg/day of CDB for 3 weeks. The reduction in symptoms was accompanied by a decrease in beta amyloid protein deposits in the hippocampus of the animals.
>> Access the research here: Chronic Treatment with 50 mg/kg Cannabidiol Improves Cognition and Moderately Reduces Aβ40 Levels in 12-Month-Old Male AβPPswe/PS1ΔE9 Transgenic Mice
Overall, CBD and THC can act to recover from memory decline even in more advanced and severe stages of the disease.This is shown by a 2016 study in which the authors argue that cognitive recovery in animal models occurred through the modulation of glutamatergic and GABAergic neurotransmission – in AD progression, there is a loss of GABAergic neurons.
>> Read Delineating the Efficacy of a Cannabis-Based Medicine at Advanced Stages of Dementia in a Murine Model
Why can medical Cannabis be an important ally in the treatment of Alzheimer’s Dementia?
The main current therapeutic arsenal for AD is acetylcholinesterase (AChE) inhibitor drugs, which increase the availability of acetylcholine in the synaptic cleft, alleviate AD symptoms, and reduce the rate of progression of cognitive decline. However, most patients are not sensitive to AChE inhibitors and do not demonstrate satisfactory clinical results with these drugs.
>> Learn more about it in this article Alzheimer’s Disease: Etiological Hypotheses and Treatment Perspectives
Furthermore, despite the increased availability of ACh showing improvements in AD symptoms, AChE inhibitors are not selective, which makes frequent a myriad of dose-dependent adverse effects, such as gastrointestinal disorders (diarrhea, nausea, vomiting, reduction appetite) and bronchoconstriction.
In this scenario, cannabinoid derivatives prove to be an interesting therapeutic toolas they act as neuroprotectors, neuroantioxidants and neuroanti-inflammatory drugs, and at the same time, they present a low profile of toxicity and adverse effects.
>> About this, read the article Canabinoides como uma nova opção terapêutica nas doenças de Parkinson e Alzheimer: uma revisão de literatura. e confira nosso Guia de como dosar derivados canabinoides.
The main phytocannabinoids CBD and THC demonstrate the ability to reduce the formation and deposition of β amyloid plaques, reduce tau protein hyperphosphorylation, modulate glutamatergic and GABAergic neurotransmission, protect neuronal toxicity and prevent degeneration of the hippocampus and cerebral cortex.
If you are interested in learning more about safe and assertive prescriptions for cannabinoid derivatives, be sure to follow our blog. Also check out the WeCann Academy’s international certification, which aims to prepare physicians to safely and effectively incorporate Endocannabinoid Medicine into their medical practice.
Aso E, Andrés-Benito P, Ferrer I. Delineating the Efficacy of a Cannabis-Based Medicine at Advanced Stages of Dementia in a Murine Model. J Alzheimers Dis. 2016 Oct 4;54(3):903-912. doi: 10.3233/JAD-160533. PMID: 27567873.
ASSOCIAÇÃO BRASILEIRA DE ALZHEIMER. Doença de Alzheimer. Disponível em: http://abraz.org.br/web/. Acesso em: 09 jun. 2021.
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Shelef A, Barak Y, Berger U, Paleacu D, Tadger S, Plopsky I, Baruch Y. Safety and Efficacy of Medical Cannabis Oil for Behavioral and Psychological Symptoms of Dementia: An-Open Label, Add-On, Pilot Study. J Alzheimers Dis. 2016;51(1):15-9. doi: 10.3233/JAD-150915. PMID: 26757043.
SOUSA, I. G. D; MARQUES N. M. Descobertas sobre o uso de cannabis nadoença de alzheimer: uma revisão da literatura. In: CONGRESSO INTERNACIONAL DE ENVELHECIMENTO HUMANO, 6, 2019, Campina Grande. Anais eletrônicos…Campina Grande, 2019.