High-Throughput Screening Assay Identifies Berberine and Mubritinib as Neuroprotection Drugs for Spinal Cord Injury via Blood-Spinal Cord Barrier Protection.

Because the breakdown of the blood-brain spinal cord barrier (BBSCB) worsens many central nervous system (CNS) diseases, prevention of BBSCB breakdown has been a major therapeutic target, especially for spinal cord injury (SCI). However, effective drugs that protect BBSCB function have yet to be developed. The purpose of the current study was 1) to develop a high-throughput screening assay (HTSA) to identify candidate drugs to protect BBSCB function, 2) to identify candidate drugs from existing drugs with newly developed HTSA, and 3) to examine the therapeutic effects of candidate drugs on SCI. Our HTSA included a culture of immortalized human brain endothelial cells primed with candidate drugs, stress with H2O2, and evaluation of their viability. A combination of the resazurin-based assay with 0.45 mM H2O2 qualified as a reliable HTSA. Screening of 1,570 existing drugs identified 90 drugs as hit drugs. Through a combination of reproducibility tests, exclusion of drugs inappropriate for clinical translation, and dose dependency tests, berberine, mubritinib, and pioglitazone were identified as a candidate. An in vitro BBSCB functional test revealed that berberine and mubritinib, but not pioglitazone, protected BBSCB from oxygen-glucose deprivation and reoxygenation stress. Additionally, these two drugs minimized BBSCB breakdown 1 day after cervical SCI in mice. Furthermore, berberine and mubritinib reduced neuronal loss and improved gait performance 8 weeks after SCI. Collectively, the current study established a useful HTSA to identify potential neuroprotective drugs by maintaining BBSCB function and demonstrated the neuroprotective effect of berberine and mubritinib after SCI.