Brain morphological and connectivity changes on MRI after stem cell therapy in a rat stroke model

Area of Science:

• Neuroscience
• Regenerative Medicine
• Medical Imaging

Background:

• Stroke animal models require robust assessment methods.
• Neuroimaging complements behavioral tests for understanding recovery mechanisms.
• Stem cell therapy efficacy in stroke is an active research area.

Purpose of the Study:

• To evaluate morphological and connectivity changes after human mesenchymal stem cell (hMSC) treatment in a rat stroke model.
• To correlate neuroimaging findings with functional recovery.
• To assess the potential of quantitative MRI as outcome predictors for stem cell therapy in stroke.

Main Methods:

• Transient middle cerebral artery occlusion in rats, followed by treatment with PBS, FBS-cultured hMSCs, or stroke patient serum-cultured hMSCs (SS-hMSCs).
• Functional assessment using modified neurological severity score (mNSS).
• Quantitative T2-weighted imaging for lesion and ventricular volume, and Diffusion Tensor Imaging (DTI) for microstructural indices (rFA, rAD, rRD) and relative fiber density (rFD).

Main Results:

• The SS-hMSCs group demonstrated the most significant functional improvement (mNSS).
• SS-hMSCs treatment led to decreased infarct lesion volume and brain atrophy compared to controls.
• DTI revealed increased rFA and rFD, and decreased rRD in the SS-hMSCs group, correlating with morphological changes and functional recovery.

Conclusions:

• Stroke patient serum-cultured hMSCs promote superior functional recovery and neuroplasticity.
• Quantitative MRI (T2-weighted imaging and DTI) effectively captures structural and microstructural changes post-treatment.
• These MRI metrics show promise as predictive biomarkers for functional recovery in stem cell therapy for stroke.