Dataset Information

Retinal-glia ischemia and inflammation induced by chronic stress: The SABPA study

ABSTRACT:

Background

Psychobiological processes linking stress and vascular diseases remain poorly understood. The retina and the brain share a common embryonic-diencephalon origin and blood-barrier physiology e.g. ongoing ischemia facilitates S100B release with astrocytic activity and glial-fibrillary-acidic-protein expression (GFAP). However, GFAP decreases revealed astrocyte pathology in the prefrontal cortex of depression/suicide cases; and might be a key mechanism in stress – disease pathways.

Methods

A chronic emotional stress phenotype independent of age, ethnicity or sex was used to stratify the current prospective cohort (N = 359; aged 46 ± 9 years) into Stress (N = 236) and no-Stress groups (N = 123). Prospective data for glia ischemia risk markers were obtained, including 24 h BP, fasting S100B, GFAP, HbA1C and tumor-necrosis-factor-α (TNF-α). At 3-yr follow-up: diastolic-ocular-perfusion-pressure (indicating hypo-perfusion risk) was measured and retinal vessel calibers were quantified from digital images in the mydriatic eye.

Results

Higher hypertension (75% vs. 16%), diabetes (13% vs. 0%) and retinopathy (57% vs. 45%) prevalence was observed in Stress compared to no-Stress individuals. Stressed individuals had consistently raised S100B, TNF-α, HbA1C and higher diastolic-ocular-perfusion-pressure, but decreases in GFAP and GFAP:S100B. Furthermore stroke risk markers, arterial narrowing and venous widening were associated with consistently raised S100B, GFAP:S100B (p = 0.060), TNF-α and higher diastolic-ocular-perfusion-pressure [Adj. R2 0.39–0.41, p ≤ 0.05]. No retinal-glia associations were evident in the no-Stress group.

Conclusions

Retinal-glia ischemia and inflammation was induced by chronic stress. Persistent higher inflammation and S100B with GFAP decreases further reflected stress-induced astrocyte pathology in the human retina. It is recommended to increase awareness on chronic stress and susceptibility for brain ischemia. Highlights • Hypertension, retinopathy and perfusion deficits are enhanced in chronic stressed individuals.• Stress-induced ischemia facilitated consistent S100B and TNF-α release but GFAP decreases.• Retinal arterial narrowing and venous widening reflected ischemia and endothelial dysfunction.• Stress-induced astrocyte ischemia pathology was evident in the human retina.• It is recommended to increase awareness on chronic stress and susceptibility for brain ischemia.

SUBMITTER: Malan L

PROVIDER: S-EPMC8474432 | biostudies-literature |

REPOSITORIES: biostudies-literature

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