Objective: We examined the glial and blood brain barrier (BBB) changes related to normal aging and PD in the Asian-Indian striatum.

Background: increases the risk of Parkinson’s disease (PD); while disease prevalence varies by ethnicity. The mild changes in the aging nigra of Asian-Indians support the lower prevalence of PD in this population compared to the Caucasians. Studies suggest the striatum is affected prior to nigra. The growing incidence of PD in Asian-Indians thus makes it relevant to study aging and PD effects on the striatum.

Method: We used 5μm formalin-fixed paraffin embedded striatal sections from PD patients and normally aging subjects who died of road traffic accidents. The sections were subjected to immunofluorescent staining for fibrinogen (FIB), glial fibrillary acidic protein (GFAP) and ionized calcium binding protein 1 (IBA1). Expression, size and number of glia were determined in the blood vessels, perivasculature, neuropil and ventricles adjoining the striatum using the LASX software (Leica Microsystems, Germany). Mixed effect model was used for statistical analysis.

Results: Striatal GFAP expression was comparable in the elderly and PD. Yet, the putamenal neuropil had significantly higher number of astrocytes in PD vis-à-vis the age-matched controls (p=.015). Ventricular astrocytes of PD brains show mild increase in size, with high GFAP expression (PD vascular p=.031, PD perivascular p=.060) compared to young. IBA1 expression was unchanged in aging and PD. Blood vessels stained intensely for FIB, but significant upregulation was limited to PD ventricular blood vessels (vascular vs perivascular, p=.045; vascular vs peri-lumen, p=.020) and putamenal neuropil (PD vs young, p=.030). Significant increase in FIB profiles was noted in PD ventricular perilumen (p=.048).

Conclusion: The astrogliosis and FIB upregulation in the putamenal neuropil in PD is suggestive of glial role in PD pathogenesis and the regional vulnerability of putamen to PD pathology. PD also induces periventricular gliosis together with intense FIB expression. Thus, gliosis may initiate BBB breach, allowing plasma FIB to leak into the striatum or vice-versa. The mild age-related effect on glia and BBB aligns with the sub-liminal nigral neurodegeneration and lower prevalence of PD in the Asian-Indians. The enhanced FIB expression in PD brains seeks in-depth analysis.

« Back to 2024 International Congress

MDS Abstracts - https://www.mdsabstracts.org/abstract/a-post-mortem-study-on-striatal-glia-and-blood-brain-barrier-integrity-in-aging-and-pd-asian-indians/