Non-motor fluctuations (NMFs) in Parkinson’s disease (PD) significantly affect patients’ well-being. Despite being identified over two decades ago, NMFs remain largely underrecognized, undertreated, and poorly understood. While they are often temporally associated with motor fluctuations (MFs) and can share common risk factors and pathophysiologic mechanisms, NMFs and MFs are currently considered distinct entities. The prevalence and severity of NMFs, often categorized into neuropsychiatric, sensory, and autonomic subtypes, vary significantly across studies due to the heterogeneous PD populations screened and the diverse evaluation tools applied. The consistent negative impact of NMFs on PD patients’ quality of life underscores the importance of further investigations via focused and controlled studies, validated assessment instruments and novel digital technologies. High-quality research is essential to illuminate the complex pathophysiology and clinical nuances of NMFs, ultimately enhancing clinicians’ diagnostic and treatment options in routine clinical practice.

Non-motor fluctuations (NMFs) in Parkinson’s disease (PD) significantly affect patients’ well-being. Despite being identified over two decades ago, NMFs remain largely underrecognized, undertreated, and poorly understood. While they are often temporally associated with motor fluctuations (MFs) and can share common risk factors and pathophysiologic mechanisms, NMFs and MFs are currently considered distinct entities. The prevalence and severity of NMFs, often categorized into neuropsychiatric, sensory, and autonomic subtypes, vary significantly across studies due to the heterogeneous PD populations screened and the diverse evaluation tools applied. The consistent negative impact of NMFs on PD patients’ quality of life underscores the importance of further investigations via focused and controlled studies, validated assessment instruments and novel digital technologies. High-quality research is essential to illuminate the complex pathophysiology and clinical nuances of NMFs, ultimately enhancing clinicians’ diagnostic and treatment options in routine clinical practice.

Non-motor fluctuations (NMFs) in Parkinson’s disease (PD) significantly affect patients’ well-being. Despite being identified over two decades ago, NMFs remain largely underrecognized, undertreated, and poorly understood. While they are often temporally associated with motor fluctuations (MFs) and can share common risk factors and pathophysiologic mechanisms, NMFs and MFs are currently considered distinct entities. The prevalence and severity of NMFs, often categorized into neuropsychiatric, sensory, and autonomic subtypes, vary significantly across studies due to the heterogeneous PD populations screened and the diverse evaluation tools applied. The consistent negative impact of NMFs on PD patients’ quality of life underscores the importance of further investigations via focused and controlled studies, validated assessment instruments and novel digital technologies. High-quality research is essential to illuminate the complex pathophysiology and clinical nuances of NMFs, ultimately enhancing clinicians’ diagnostic and treatment options in routine clinical practice.

Background and Objectives: The physiological oxygen tension in fetal brains (∼3%, physioxia) is beneficial for the maintenance of neural stem cells (NSCs). Sensitivity to oxygen varies between NSCs from different fetal brain regions, with midbrain NSCs showing selective susceptibility. Data on Hif-1α/Notch regulatory interactions as well as our observations that Hif-1α and oxygen affect midbrain NSCs survival and proliferation prompted our investigations on involvement of Notch signalling in physioxia-dependent midbrain NSCs performance. Methods: and Results: Here we found that physioxia (3% O2 ) compared to normoxia (21% O 2 ) increased proliferation, maintained stemness by suppression of spontaneous differentiation and supported cell cycle progression. Microarray and qRT-PCR analyses identified significant changes of Notch related genes in midbrain NSCs after long-term (13 days), but not after short-term physioxia (48 hours). Consistently, inhibition of Notch signalling with DAPT increased, but its stimulation with Dll4 decreased spontaneous differentiation into neurons solely under normoxic but not under physioxic conditions. Conclusions Notch signalling does not influence the fate decision of midbrain NSCs cultured in vitro in physioxia, where other factors like Hif-1α might be involved. Our findings on how physioxia effects in midbrain NSCs are transduced by alternative signalling might, at least in part, explain their selective susceptibility to oxygen.