From Forest to Brain: Tamarack Bark in Alzheimer’s Research

Hi, my name is Molly, and I'm Ashton.

We are from the Naskapi Nation. Our project is about Tamarack tea and how it could help prevent the chemical reaction that causes Alzheimer's. We found the idea in our culture class about the traditional uses of tamarack tea. The tea is known as a nerve medicine, so we decided to look into Alzheimer's. Laboratory tests done at the University of Quebec assessed the effects of various inhibitors' activity. Alzheimer's medication reduces breakdown, while Tamarack tea extracts demonstrates significant reduced breakdown, especially in concentrated forms. A total phenolic content test revealed that 50% glycerine had the highest content. We also did a community survey, and the results showed that the tea is regularly consumed and that people in the community feel clearer headed after drinking it, noting its potential benefits for brain health derived from traditional practices. In the future, we would love to continue the project by experimenting with trees in different seasons. We would also want to see if the tea samples would be able to survive the digestive system.

We undertook this project to investigate whether the traditional Indigenous tamarack bark tea has actual biochemical effects that might relate to Alzheimer's disease. We wanted to bridge community knowledge of the tea preparation with laboratory experiments. We wanted to understand both the traditional knowledge and the biochemical activity of tamarack to explore its potential protective effects against neurodegenerative disease, in a way that respects its traditional use.

This project began in a culture class where we heard about the uses of tamarack bark tea. We were fascinated to learn about how it has been traditionally used to improve memory and health in general. The wisdom from Indigenous perspectives, particularly around tamarack being a "nerve medicine", inspired us to see if these traditional methods could be backed up by recent science.

We wanted to see whether different methods and solvents in whoch th tea os prepared affects inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzymes of Alzheimer's disease.

This research can benefit Indigenous communities, people those who are interested in medicinal plants, and herbal medicine. It can also assist scientists in biomedical research and development, such as Alzheimer's disease research.

This project bridges traditional and scientific knowledge. By demonstrating the value of cultural practices in science, it encourages the respect of traditional knowledge systems while helping with Alzheimer's disease research. Long-term, this type of research may help create more economical, natural, and culturally relevant strategies for brain health, and help to conserve traditional practices.

A mixed-methods design was used in this study, including 4 lab experiments and a community survey to examine the biochemical effects of tamarack bark

For the laboratory experiments, the tamarack bark was washed and dried in the air and cut to enhance extraction. Two hot-water samples were made by boiling the bark for 30 and 60 minutes, and cold-water extracts by letting the bark steep for 48 hours. A 50% glycerine solution was used to create a glycerine-water extract for 48 hours. Evaporation was controlled to form a concentrated extract. All five samples were tested at Université du Québec à Trois-Rivières.

Lab Test 1: The tamarack bark extracts of different concentrations and boiling periods were incubated with the Acetylcholinesterase (AChE) enzyme using Ellman’s method. The enzyme activity was measured by the yellow colour obtained at 412 nm, an indication of the breakdown of the substrate acetylthiocholine.

Lab Test 2: To test for additional enzyme activity related to Alzheimer’s, we used the Butyrylcholinesterase inhibitory assay with Butyrylcholinesterase substrate.

Lab Test 3: The total of the phenolic compounds (polyphenols and flavonoids) of the tamarack bark extracts is measured using the Folin-Ciocalteu Total Phenolic Content (TPC) Assay. These compounds are important as they are related with antioxidant and neuroprotective activities that are relevant for studies on Alzheimer’s disease.

Lab Test 4: The Chicken Acetylcholinesterase (AChE) ELISA Kit was another biochemical procedure that was employed to further explore the relationship between tamarack bark extract and acetylcholinesterase. This test provided a supplementary piece of evidence, as it was possible to identify the presence of the enzyme in this test.

Survey: It included 18 years and older, asking them about how often they drink tea, how they make it, how they think it influences their brain health, and the importance of traditional knowledge.

Observations:

Lab Test 1 revealed that higher concentrations of Tamarack bark extracts were able to slow down the breakdown of acetylcholine, showing the potential of tea's bioactive compounds in the enzyme regulation of Alzheimer’s disease. Rivastigmine and galantamine showed lower inhibition than the concentrated extracts, while quercetin and kaempferol showed medium effects.

In Lab Test 2, the % inhibition level was similar for tea extracts and rivastigmine. Inhibition was higher for the sample with cold water and all other extracts at room temperature than for galanthamine. Plant-derived inhibitors such as quercetin and kaempferol also inhibited the enzyme. The no enzyme well did not change colour confirming the accuracy of the assays. The stronger extracts did the higher inhibition.

Lab Test 3 determined the total phenolic content of tamarack bark extracts by different techniques of extraction by utilizing the Folin-Ciocalteu test. Sample D (50% glycerine-water extract) and sample E (concentrated extract) had the highest phenolic content, sample B (60-minute boil) and sample C (cold-water extract) had moderate phenolic content and sample A (30-minute boil) had the lowest phenolic content.

Lab Test 4: In this test, the control sample that had pure buffer and the standard enzyme showed a clear positive result, which proves that acetylcholinesterase was successfully detected under the conditions of the assay. However, the tamarack-treated sample possessed a significant shift in the intensity of the colour, which can be interpreted as the high interaction between the plant extract and the enzyme system.

The community survey indicated the common use of Tamarack bark tea, which was usually boiled. Memory support and mental clarity were enhanced by longer boiling times (20-60 minutes).In order to present the data in the survey in a graphical manner, we transformed the qualitative data into numerical data based on a 0 to 5 scale. This was to facilitate easy interpretation and comparison of results across aspects. The ratings were given according to the comparative intensity and frequency of the answers of each type.

Results and Analysis:

Lab Test/Assay 1: Acetylcholine (AChE)

No inhibitor:

Acetylcholine → [AChE enzyme] → Choline + Acetate

With inhibitors:

Tamarack bark tea extracts:

Concentrated extract → Strong inhibition leading most acetylcholine

Diluted extracts [including 30 min, 60 min, cold water, glycerine] → Partial inhibition leading some acetylcholine

Lab Test/Assay 2: Butyrylcholinesterase (BuChE)

No inhibitor:

Butyrylcholine → [BuChE enzyme] → Choline + Butyrate

With inhibitors:

Tamarack bark tea extracts:

Concentrated → Strong inhibition leading more than Galantamine

60 min boil extract → Moderate inhibition and similar to Rivastigmine

A lighter yellow or pale brown appearance in these lab assays implies more enzyme inhibition.

Lab Test/Assay 3: Total Phenolic Content (TPC)

Linearity of the gallic acid curve indicates the validity of the 3rd assay.

Lab Test/Assay 4: Chicken Acetylcholinesterase (AChE) ELISA

The colour change between the buffer and the concentrated sample results suggests that there are compounds in tamarack bark that bind to acetylcholinesterase and affect the detectable acetylcholinesterase in the environment.

The survey found community interest in Tamarack bark tea is high due to its traditional use.

Discussion: This research explores the connection between traditional knowledge and biochemical evidence supporting the role of tamarack bark tea in Alzheimer's research. Results suggest the biochemical activity of tamarack extracts is highly dependent on preparation techniques, revealing the importance of extraction parameters as well as the presence of active compounds.

Compounds in the tamarack extracts bind to cholinesterase enzymes and inhibit them. This is consistent with Alzheimer's studies of acetylcholinesterase and butyrylcholinesterase inhibition to control neurotransmitters. The active roles of these extracts suggest specific interactions with the enzyme structure through the ELISA test.

The present study bridges the gap between biochemical findings and ethnographic data, demonstrating the biochemically effective traditional preparation processes and the empirically based ethnobotanical traditional knowledge for the creation of plant-based treatments.

The tamarack bark tea is characterized by the complexity of its chemical composition, preparation, and biological activity. The integration of traditional and scientific methods is important for its therapeutic use.

Conclusions and Learnings: This study relates lab and local traditional and medicinal knowledge to gain a better understanding of tamarack bark and emphasizes the role of traditional knowledge in employing experimental approaches to improve natural resources.

The results of this study reveal that tamarack bark contains neuroactive polyphenolic chemicals that require further study of mechanisms of action, isolation of compounds, and evaluations of complex systems.

In Alzheimer’s disease research, this project successfully integrates ethnobotany, indigenous knowledge, and modern science for improved understanding of the potential of tamarack bark tea.

If we could have done the project differently, then we could have used different species of the Tamarack Bark, harvest the tree bark in different seasons.

For improvement, we could have incorporated a larger sample (community participants).

Future studies could investigate the effect of different boiling times on the extraction of phenolic active compounds in Tamarack bark tea. Moreover, we could investigate Tamarack bark tea's infusion and/or compatibility with other indigenous medicines or foods. Studies on the safety and optimum concentration of the tea over time could also be examined, particularly for daily use.

Our adult and scientific supervisor: Ms. Shaveta Sharma, supervised our lab work and field surveys.

Our Naskapi Cultural Teacher: Ms. Shannon Uniam, for providing us with Tamarack Bark and the technique to make the tea.

Our Elders: For giving us knowledge on the Tamarack Bark Tea.

Quebec Indigenous Science Fair (QISF) ethics committee: Marc Lalande, President, and Martine Couture, Secrétaire.

Mentor: Dr. Natacha Merindol, Associate Professor at the Université du Québec à Trois-Rivières, who provided us with the university lab of Isabel Desgagné-Penix, to perform our lab tests.

Our Community Members: for filling out our surveys.

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