OCLN and serum lipopolysaccharide activity: Isoorientin (25 and 50 mg/kg) and LiCl (100 mg/kg) upregulated the expression of occludin, ZO-1 and p-GSK3β in the brain of endotoxemia mice (Figure 5), showing a good potential of reversing the destruction of BBB and treatment for GSK3β-related brain diseases.