Alzheimer's Disease and Toxins Produced by Marine Dinoflagellates: An Issue to Explore

Area of Science:

• Marine Biology
• Neuroscience
• Pharmacology

Background:

• Alzheimer's disease (AD) is characterized by β-amyloid plaques and tau hyperphosphorylation.
• Marine natural products are being investigated for therapeutic potential in neurodegenerative diseases.
• Understanding marine toxins' effects on AD pathology is crucial for developing new treatments.

Purpose of the Study:

• To examine marine dinoflagellate toxins for their impact on Alzheimer's disease pathology.
• To explore the potential of specific marine toxins in reducing β-amyloid plaques and tau hyperphosphorylation.
• To discuss current advances and challenges in Alzheimer's disease treatment and global patterns.

Main Methods:

• Focused on yessotoxins (YTXs), gymnodimine (GYM), spirolides (SPXs), and gambierol, known to reduce AD markers.
• Described okadaic acid (OA) and derivatives that inhibit protein phosphatase activity, increasing tau phosphorylation.
• Considered the use of OA in zebrafish models to test in vivo drug efficacy for AD.

Main Results:

• YTXs, GYM, SPXs, and gambierol demonstrated a reduction in β-amyloid plaques and tau hyperphosphorylation.
• OA and its derivatives were identified as facilitators of tau protein hyperphosphorylation.
• Marine toxins present a dual action: some mitigate AD hallmarks, while others can induce them, useful for drug screening.

Conclusions:

• Marine toxins offer promising avenues for Alzheimer's disease therapeutic strategies.
• The study highlights the need for further research into the distinct mechanisms of action of different marine toxins.
• Constraints on marine toxin production for research and therapeutic use were considered.