Unraveling the potential of gasotransmitters as neurogenic and neuroprotective molecules: focus on Alzheimer's and Parkinson's diseases.

Alzheimer's disease and Parkinson's disease are the two most prevalent neurodegenerative disorders worldwide, both characterized by progressive neuronal loss. Despite distinct pathophysiological features, they share cellular dysfunctions such as abnormal protein aggregation, oxidative stress, and neuroinflammation, research into which might be beneficial for developing novel therapeutic strategies that could tackle both conditions. This review highlights the emerging role of the gasotransmitters nitric oxide, carbon monoxide and hydrogen sulfide as modulators of adult neurogenesis and neuroprotection in Alzheimer's disease and Parkinson's disease. We have gathered recent evidence demonstrating that these endogenous gases exert anti-inflammatory, antioxidant, and anti-apoptotic effects, and, critically, promote neurogenesis - suggesting a dual neuroprotective and neuroregenerative therapeutic potential. The unique physicochemical features of these gasotransmitters, including their ability to cross the blood-brain barrier and diffuse rapidly throughout the neural tissue, further support their suitability as candidates for innovative neuroregenerative treatments. While clinical translation remains challenging, harnessing the neurogenic and neuroprotective actions of these gasotransmitters may offer transformative avenues for addressing the increasing burden of Alzheimer's disease and Parkinson's disease.