The aim of the study was to explore the therapeutic effect of ultrasound targeted destruction of schisandrin A contrast microbubbles on liver cancer and its related mechanism.
The Span-PEG microbubbles loaded with schisandrin A were prepared using Span60, NaCl, PEG-1500, and schisandrin A. The loading rate of schisandrin A in Span-PEG composite microbubbles was determined by ultraviolet spectrophotometry method. The Walker-256 cell survival rate of schisandrin A was determined by 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide (MTT) assay. The content of schisandrin A in the cells was determined by high performance liquid chromatography. Ultrasound imaging was used to evaluate the therapeutic effect
The composite microbubbles were uniform in size, and the particle size distribution was unimodal and stable, which met the requirements of ultrasound contrast agents. The loading rate of schisandrin A in Span-PEG microbubbles was 8.84 ± 0.14%, the encapsulation efficiency was 82.24±1.21%. The IC50 value of schisandrin A was 2.87 μg/mL. The drug + microbubbles + ultrasound (D+M+U) group had the most obvious inhibitory effect on Walker-256 cancer cells, the highest intracellular drug concentration, the largest reduction in tumor volume, the most obvious reduction in serum inflammatory factors, and the most obvious improvement in pathological results. The results of immunohistochemistry showed that HIF-1α, VEGF and VEGFR-2 protein decreased most significantly in D+M+U group (
Schisandrin A had an anti-tumor effect, and its mechanism might be related to the inhibition of the PI3K/AKT/mTOR signaling pathway. The schisandrin A microbubbles could promote the intake of schisandrin A in tumor cells after being destroyed at the site of tumor under ultrasound irradiation, thus playing the best anti-tumor effect.