Serum glial cell line-derived neurotrophic factor (GDNF) a potential biomarker of executive function in Parkinson's disease

Cerebrospinal fluid mesencephalic astrocyte-derived neurotrophic factor: A moderating effect on sleep time and cognitive function

BACKGROUND

Sleeping late has been associated with cognitive impairment, and insufficient sleep can affect the secretion of feeding-related cytokines. Feeding-related cytokines may contribute to cognitive deficits resulting from delayed bedtime. Glial cell line-derived neurotrophic factor (GDNF) and mesencephalic astrocyte-derived neurotrophic factor (MANF), which are feeding-related neurotrophic factors, have been associated with improved cognitive function and neuroprotective abilities. Enhanced expression of GDNF and MANF is linked to increased energy expenditure and hyperphagia, respectively.

AIMS

This study aimed to investigate the association between cerebrospinal fluid (CSF) GDNF, MANF, cognition, and sleep time and to explore the moderating effects of GDNF and MANF on cognitive impairment in individuals who sleep late.

METHOD

This cross-sectional study included participants (mean age 31.76 ± 10.22 years) who were categorized as ≤23 o'clock sleepers (n = 66) and >23 o'clock sleepers (n = 125) based on sleep time. Cognition was assessed using Montreal Cognitive Assessment (MoCA), and GDNF and MANF levels in CSF were measured.

RESULTS

MANF may play a moderating role in the relationship between sleep time and cognition (R2 = 0.06, β = 0.59, p = 0.031). Age showed a negative correlation with MoCA scores (R2 = 0.08, β = -0.18), while education exhibited a positive correlation (β = 0.17, both p < 0.05). Only ≤23 o'clock sleepers exhibited a negative correlation between MANF levels and BMI (r = -0.35, p = 0.005).

CONCLUSIONS

This study provides hitherto undocumented evidence of the potential protective effect of CSF MANF on cognitive impairment of late sleepers, which suggests that maintaining a regular sleep schedule may contribute to cognition and overall health, with MANF playing a role in this process.

GDNF/GFRA1 signaling contributes to chemo- and radioresistance in glioblastoma

Glioblastoma is the most common primary brain tumor in adults, characterized by an inherent aggressivity and resistance to treatment leading to poor prognoses. While some resistance mechanisms have been elucidated, a deeper understanding of these mechanisms is needed to increase therapeutic efficacy. In this study we first discovered glial-cell derived neurotrophic factor (GDNF) to be upregulated in patient-derived glioblastoma spheroid cultures after chemotherapeutic temozolomide treatment, through RNA-Seq experiments. Therefore, we investigated the role of the GDNF/GDNF receptor alpha 1 (GFRA1) signaling pathway as a resistance mechanism to chemotherapy with temozolomide and lomustine, as well as irradiation using patient-derived glioblastoma spheroid cultures. With qPCR experiments we showed a consistent upregulation of GDNF and its primary receptor GFRA1 following all three lines of treatment. Moreover, CRISPR/Cas9 knock-outs of GDNF in two patient-derived models sensitized these cells to chemotherapy treatment, but not radiotherapy. The increased sensitivity was completely reversed by the addition of exogeneous GDNF, confirming the key role of this factor in chemoresistance. Finally, a CRISPR KO of GFRA1 demonstrated a similar increased sensitivity to temozolomide and lomustine treatment, as well as radiotherapy. Together, our findings support the role of the GDNF/GFRA1 signaling pathway in glioblastoma chemo and radioresistance.

Poly(rC)-binding protein 1 alleviates neurotoxicity in 6-OHDA-induced SH-SY5Y cells and modulates glial cells in neuroinflammation

BACKGROUND

Parkinson's disease (PD) is a debilitating neurodegenerative condition characterized by the loss of dopaminergic neurons and neuroinflammation. Previous research has identified the involvement of Poly (rC)-binding protein 1 (PCBP1) in certain degenerative diseases; however, its specific mechanisms in PD remain incompletely understood.

METHODS

In this study, 6-OHDA-induced neurotoxicity in the cell lines SH-SY5Y, BV-2 and HA, was used to evaluate the protective effects of PCBP1. We assessed alterations in BDNF levels in SY5Y cells, changes in GDNF expression in glial cells, as well as variations in HSP70 and NF-κB activation. Additionally, glial cells were used as the in vitro model for neuroinflammation mechanisms.

RESULTS

The results indicate that the overexpression of PCBP1 significantly enhances cell growth compared to the control plasmid pEGFP/N1 group. Overexpression of PCBP1 leads to a substantial reduction in early apoptosis rates in SH-SY5Y, HA, and BV-2 cells, with statistically significant differences (p < 0.05). Furthermore, the overexpression of PCBP1 in cells results in a marked increase in the expression of HSP70, GDNF, and BDNF, while reducing NF-κB expression. Additionally, in SH-SY5Y, HA, and BV-2 cells overexpressing PCBP1, there is a decrease in the inflammatory factor IL-6 compared to the control plasmid pEGFP/N1 group, while BV-2 cells exhibit a significant increase in the anti-inflammatory factor IL-10.

CONCLUSION

Our findings suggest that PCBP1 plays a substantial role in promoting cell growth and modulating the balance of neuroprotective and inflammatory factors. These results offer valuable insights into the potential therapeutic utility of PCBP1 in mitigating neuroinflammation and enhancing neuronal survival in PD.

The significance of glial cell line-derived neurotrophic factor analysis in Progressive Supranuclear Palsy

Progressive Supranuclear Palsy (PSP) is an atypical parkinsonism. Major subtypes of the disease: PSP-Richardson's Syndrome (PSP-RS) and PSP Parkinsonism Predominant (PSP-P) vary in clinical features, the pathomechanism remains unexplored. The aim of this work is to analyze the relevance of glial cell line-derived neurotrophic factor (GDNF) evaluation in the serum and cerebrospinal fluid (CSF) in PSP subtypes and to verify its significance as a possible factor in the in vivo examination. Authors assessed the concentration of GDNF in the serum and CSF of 12 patients with PSP-RS, 12 with PSP-P and 12 controls. Additionally authors evaluated patients using Unified Parkinson's Disease Rating Scale-III part (UPDRS-III), Frontal Assessment Battery (FAB) and Magnetic Resonance Imaging (MRI). The evaluation revealed significantly increased concentrations of GDNF in the CSF among PSP-RS patients and substantially increased concentrations of GDNF in the serum in PSP-P. Though the GDNF concentrations differentiated PSP subtypes, no correlations between with clinical factors were observed however certain correlations with atrophic changes in MRI were detected. GDNF is a factor which may impact the pathogenesis of PSP. Possible implementation of GDNF as a therapeutic factor could be a perspective in the search for therapy in this currently incurable disease.