Recent literature review:
Probiotic supplementation for anxiety symptoms in people with Parkinson’s disease: a randomized, double-blind, placebo-controlled trial 2026
12-week probiotic supplement containing nine bacterial strains (Bifidobacterium bifidum W23, Bifidobacterium lactis W51 and W52, Lactobacillus acidophilus W37, Levilactobacillus brevis W63, Lacticaseibacillus casei W56, Ligilactobacillus salivarius W24, and Lactococcus lactis W19 and W58) on anxiety symptoms in 61 individuals with PD and clinically significant anxiety. Both the probiotic (n = 30) and placebo (n = 31) groups showed significant within-group improvements on the Parkinson Anxiety Scale, with no significant between-group differences. The probiotic group showed a statistically significant improvement on the Montreal Cognitive Assessment compared with placebo (adjusted mean difference of 1.1 points; 95% confidence interval: 0.04–2.1; p = 0.043). No treatment effects were seen on other secondary outcomes, including depression, constipation, or motor symptoms.
Blood-based biomarkers of ferroptosis in Parkinson’s disease 2026
At baseline, UPDRS III-Worst OFF was positively correlated with log-4-HNE (p = 0.007). PDQ-39 was negatively correlated with log-ferritin concentration (p = 2.38 10−4), selenium concentration (p = 0.033) and the rs7887981 in the ACSL4 gene (p = 0.033).
Our results strongly support an association between 4-HNE levels and the progression of motor disability in advanced PD. They also provide multiple lines of evidence favoring a role for ferroptosis in PD progression. Subject to further validation, they could therefore be used to select and stratify patients for future clinical trials.
We also found that higher selenium and log-ferritin levels were both associated with a better quality of life, as attested by a lower PDQ-39 total score (−0.118 ± 0.055; p = 0.033 and − 4.324 ± 1.167; p = 2.38 10−4; respectively). But after adjustment for multiple comparisons, only the association between log-ferritin and PDQ-39 stayed significant (adjusted p-value = 0.094 and 1.34*10−3; respectively).
In particular, we found that lower log-ferritin levels at baseline were associated with a poorer quality of life. These results suggest that alterations to iron metabolism influenced PD severity in our cohort. Ferritin is an essential protein for iron storage in the body, and it serves as a marker of inflammation. Our observations are consistent with the reported lower concentration of ferritin in the substantia nigra of PD patients than in that of healthy patients (Dexter et al., 1990; Connor et al., 1995). Interestingly, ferritin degradation by ferritinophagy has been shown to be instrumental in triggering or maintaining ferroptosis (Ajoolabady et al., 2021). In a context of ferroptosis, low ferritin concentration may lead to an increase in the labile iron pool, causing oxidative damage and resulting in lipid peroxidation and an increase in 4-HNE levels. However, low ferritin levels may also be linked to mild iron deficiency or to iron consumption/relocation by macrophages during inflammatory responses.
Elevated levels of colonic interleukin-1beta and interleukin-8 in isolated REM sleep behavior disorder without associated changes in permeability 2026
Our findings provide evidence that enteric inflammation is present at a moderate level in prodromal PD, not higher than in individuals with established PD, and without concurrent changes in intestinal permeability.
Blood mtDNA markers of mitochondrial subtype and early-onset Parkinson’s disease biology 2026
MtDNA damage markers, particularly deletion burden, capture mitochondrial dysfunction arising from both genetic and environmental influences and are detectable across early clinical stages of PD. While not serving as stand-alone diagnostic biomarkers, mtDNA measures provide complementary biological information within a multimodal framework and may support patient stratification based on mitochondrial involvement using a minimally invasive approach.
Higher glymphatic system activity is linked to longer prodromal stage in isolated REM sleep behavior disorder: a possible protective factor 2026
These findings suggest that preserved glymphatic function may be associated with prolonged prodromal stability in iRBD.
=> Could this be a possible protective factor?
Deciphering novel genotypic biomarkers and functional alterations in double strand break repair pathways for Parkinson’s disease 2026
Together, the results highlight a critical role of inherited DSB repair deficiencies in PD etiology and suggest potential avenues for personalized risk prediction and prevention.
The surprising science behind red-light therapy — and how it really works
Researchers have seen benefits in animal models of Parkinson’s last for weeks after treatment, and early human trials are under way, using optical fibres that put the light close to the diseased cells
RFC1-related disorders: A case series of 4-aminopyridine and acetyl-DL-leucine treatment 2026
Tanganil failed?
In this multicenter case series of 30 genetically confirmed RFC1-positive patients, we evaluated the real-world effects of 4-AP and ADLL, both administered on a named patient use basis. Only a minority of patients reported subjective clinical benefits, and objective improvements were restricted to gait and observed in a similarly small proportion.
GLP1R expression and parkinson’s disease and related disorders in GLP-1RA-treated type 2 diabetes 2026
These findings link a mechanism-anchored genetic proxy for higher systemic GLP1R expression to a lower risk of incident PDRD among GLP-1RA–treated adults with type 2 diabetes. Systemic GLP1R-mediated pathways may be relevant to interindividual differences in observed PDRD risk, and genetic instruments for GLP1R expression may inform hypotheses for future PDRD trial design.
@John_Hemming: a few interesting papers here for you, especially on ferritin levels and mtDNA.
CAUTION - DISREPUTABLE AUTHORS INVOLVED!!!
