Assessments of plasma acyl-ghrelin levels in Parkinson's disease patients treated with deep brain stimulation

Associations between gut microbiota characteristics and non-motor symptoms following pharmacological and surgical treatments in Parkinson's disease patients

BACKGROUND

The gut microbiota has been implicated in Parkinson's disease (PD), with alterations observed in microbial composition and reduced microbial species richness, which may influence gastrointestinal symptoms in PD patients. It remains to be determined whether the severity of gastrointestinal symptoms correlates with microbiota variations in PD patients treated pharmacologically or with subthalamic nucleus deep brain stimulation (STN-DBS) therapy. This study aims to explore how these treatments affect gut microbiota and gastrointestinal symptoms in PD, identifying specific microbial differences associated with each treatment modality.

METHODS

A total of 42 individuals diagnosed with PD, along with 38 age-matched household control participants, contributed stool samples for microbiota characterization. Differences in the gut microbiota across various groups of PD patients and their households were identified through comprehensive sequencing of the 16S rRNA gene amplicon sequencing.

KEY RESULTS

Differences in microbial communities were observed between PD patients and controls, as well as between PD patients receiving pharmacological treatment and those with STN-DBS. Pharmacologically treated advanced PD patients have higher gastrointestinal dysfunctions. Gut microbiota profile linked to STN-DBS and reduced levodopa consumption, characterized by its anti-inflammatory properties, might play a role in diminishing gastrointestinal dysfunction relative to only pharmacological treatments.

CONCLUSIONS & INFERENCES

Advanced PD patients on medication exhibit more gastrointestinal issues, despite relatively stable microbial diversity, indicating a complex interaction between gut microbiota, PD progression, and treatment effects. An imbalanced gut-brain axis, particularly due to reduced butyrate production, may lead to constipation by affecting the enteric nervous system, which emphasizes the need to incorporate gut microbiome insights into treatment strategies.

Body mass index in patients with Parkinson's disease: a systematic review

Body mass index (BMI) has been found to have an impact on neurodegenerative diseases such as Parkinson's disease (PD). Several studies suggested that patients with PD have a lower BMI compared with controls. However, some studies indicated the differences between patients and controls as statistically insignificant. We performed this meta-analysis to clarify the relationship between BMI and PD based on the studies published from 1975 to April 2023 in the PubMed, Embase, and Cochrane Library databases. In total, 18 case-control studies met the inclusion criteria for meta-analysis. We found a statistically significant difference in mean BMI between patients with PD and healthy controls {standardized mean difference (SMD) [95% confidence interval (CI)] = -0.36 (-0.43, -0.29), P < 0.05}. Regarding sex, seven studies were included in the meta-analysis for female/male patients with PD. The mean BMI was significantly different between males with PD and healthy males [SMD (95% CI) = -0.34 (-0.47, -0.22), P < 0.05]. Moreover, the mean BMI of females with PD was significantly different from that of corresponding healthy females [SMD (95% CI) = -0.44 (-0.57, -0.30), P < 0.05]. The meta-analysis demonstrates a significantly lower BMI in patients with PD, but no gender differences, when compared with their respective healthy individuals.NEW & NOTEWORTHY The meta-analysis demonstrates a significantly lower body mass index in patients with PD, but no gender differences, when compared with their respective healthy individuals.

"Sibling" battle or harmony: crosstalk between nesfatin-1 and ghrelin

Ghrelin was first identified as an endogenous ligand of the growth hormone secretagogue receptor (GHSR) in 1999, with the function of stimulating the release of growth hormone (GH), while nesfatin-1 was identified in 2006. Both peptides are secreted by the same kind of endocrine cells, X/A-like cells in the stomach. Compared with ghrelin, nesfatin-1 exerts opposite effects on energy metabolism, glucose metabolism, gastrointestinal functions and regulation of blood pressure, but exerts similar effects on anti-inflammation and neuroprotection. Up to now, nesfatin-1 remains as an orphan ligand because its receptor has not been identified. Several studies have shown the effects of nesfatin-1 are dependent on the receptor of ghrelin. We herein compare the effects of nesfatin-1 and ghrelin in several aspects and explore the possibility of their interactions.