Andrographolide: Mechanisms and Therapeutic Potential in Alzheimer's and Parkinson's Disease

Neurodegenerative diseases such as Alzheimer's disease (AD) and Parkinson's disease (PD) are characterized by the progressive loss of specific neuronal cell populations and are associated with protein aggregates. Current therapeutic approaches are still limited due to the complexity and heterogeneity of these diseases, which points toward an urgent need to discover and develop new therapeutic agents. Natural compounds are a promising source of novel bioactive agents targeting multiple mechanisms of action implicated in neurodegeneration. Andrographolide (ANDRO) is a natural compound extracted from Andrographis paniculata, a traditional Chinese herb known for its anti-inflammatory and antioxidant properties, which has emerged as a potential neuroprotective agent due to its ability to cross the blood-brain barrier (BBB). ANDRO can exert neuroprotective effects by modulating numerous transcription factors and signaling pathways across different cell types in the central nervous system (CNS). It has been described that ANDRO reverses cognitive and/or motor impairments in AD and PD study models. However, the cellular and molecular mechanisms behind these protective effects are still being elucidated. In this review, we analyze the most recent findings on ANDRO, a neuroprotective agent with multiple biological targets that could reduce the progression of the most prevalent neurodegenerative diseases, AD and PD.