The acute effects of nonstructural-1 protein dengue virus type 2 on wet liver weight, zonulin expression and serum zonulin.

Background and objectives: Intestinal leakage commonly occurs in severe dengue infection with zonulin as a biomarker. The aim of this study was to determine the effects of NS1 on liver weight, zonulin expression and serum zonulin levels.

Materials and methods: This laboratory experiment used 18 ddY mice, which were randomly divided into control (C), PBS (T1), and PBS + NS1 (T2) groups. Mice in the T1 and T2 groups were intravenously injected with 500 μl PBS only and 50 μg NS1 respectively. Mice blood samples were collected before and after three-day treatment for measurement of zonulin level. The fresh liver was weighted directly and were then used for immunostaining.

Results: The C group had lower wet liver weight compared to the T groups (p=0.001). Increased expression of liver zonulin was found in the T2 group, significant different from the C (p=0.014) and T1 groups (p=0.020). After treatment, serum zonulin levels in the T1 group was higher than that of the T1 group before treatment (p=0.035) but not in control (p=0.753) and T2 groups (p=0.869).

Conclusion: Administration of 50 μg NS 1 increases wet liver weight and zonulin expression in hepatocytes, but did not increase serum zonulin levels in ddY mice.