Microbubble-mediated sonothrombolysis with BR38 of a venous full blood thrombus in a rat embolic stroke model.

ABSTRACT:

Background

Early recanalization of an occluded vessel is associated with a better clinical outcome in acute ischemic stroke. Intravenous thrombolysis using recombinant tissue plasminogen activator (rt-PA) is only available in a minority of patients and often fails to reopen the occluded vessel. Mechanical recanalization is more effective in this matter but only available for selected patients when a thrombectomy centre can be reached. Therefore, sonothrombolysis might represent an alternative or complementary approach. Here, we tested microbubble-mediated sonothrombolysis (mmSTL) in a thromboembolic stroke model for middle cerebral artery occlusion (MCAO) in rats.

Methods

Sixty-seven male Wistar rats underwent MCAO using an autologous full blood thrombus and were randomly assigned to four groups receiving rt-PA, mmSTL, a combination of both, or a placebo. Diagnostic workup included neurological examination, assessment of infarct size, and presence of intracerebral haemorrhage by magnetic resonance imaging (MRI) and presence of microbleedings in histological staining.

Results

Neurological examination revealed no differences between the treatment groups. In all treatment groups, there was a reduction in infarct size 24 hours after MCAO as compared to the placebo (P≤0.05), but there were no differences between the active treatment groups (P>0.05) (placebo 0.75±0.10 cm³; mmSTL 0.43±0.07 cm³; rt-PA 0.4±0.07 cm³; mmSTL + rt-PA 0.27±0.08 cm³). Histological staining displayed intracerebral microbleedings in all animals. The frequency of gross bleeding detected by MRI did not differ between the groups (placebo 3; mmSTL 4; rt-PA 2; mmSTL + rt-PA 2; P>0.05) and was not associated with worse performance in clinical testing (P>0.05). There were no statistical differences in the mortality between the groups (P>0.05).

Conclusions

Our study showed the efficacy and safety of mmSTL with or without rt-PA in an embolic rat stroke model using a continuous full blood thrombus. Sonothrombolysis might be useful for patients who need to be transported to a thrombectomy centre or for those with distal vessel occlusion.

SUBMITTER: Braun T 

PROVIDER: S-EPMC8339866 | biostudies-literature |

REPOSITORIES: biostudies-literature