Meroterpenoids from Terrestrial and Marine Fungi: Promising Agents for Neurodegenerative Disorders—An Updated Review

(1) Background: Meroterpenoids represent a remarkably diverse class of natural secondary metabolites, some of which are synthesized via terpenoid biosynthetic pathways. Over the past ten years, these compounds have gained interest because of their wide range of biological activities, such as anti-cholinesterase, COX-2 inhibitory, antibacterial, antiviral, antidiabetic, antioxidant, anti-inflammatory, antineoplastic, and cardioprotective properties. This review aims to consolidate the recognized neuroprotective effects of meroterpenoids from marine and terrestrial fungi. (2) Methods: Data compiled from several databases, including PubMed, Science Direct, Scopus and Google Scholar, include articles published since 2000 using keywords such as “neuroprotective”, “fungi”, “mushroom”, “marine sponge” “Alzheimer's”, and “dementia” in connection with “meroterpenoids”. (3) Results: The reviewed studies indicate that further investigation is required, suggesting that meroterpenoids may serve as promising therapeutic agents for neurodegenerative diseases by modulating different cell signaling pathways and exhibiting different and often combined mechanisms of action to ameliorate neuronal damage and dysfunction. Reported activities include anti-cholinesterase, antioxidant, BACE1 inhibition and anti-inflammatory, all of which have potential in the treatment of dementia associated with neurodegenerative diseases such as Alzheimer's and Parkinson's. The advantages of slowing disease progression, enhancing cognitive abilities, and elevating quality of life have been emphasized. (4) Conclusions: Meroterpenoids have the potential to be developed as effective tools for neuropathological diseases. Ongoing research to elucidate the various neuroprotective pathways remains essential and requires further investigation.