Dihydroartemisinin inhibits multiplication of Brucella suis vaccine strain 2 in murine microglia BV2 cells via stimulation of caspase‑dependent apoptosis.

Abstract

Brucellosis, caused by a facultative intracellular parasite Brucella species, is the most common bacterial zoonotic infection worldwide. Brucella can survive and proliferate in several phagocytic and non-phagocytic cell types. Human brucellosis has similar clinical symptoms with systemic diseases, which may lead to delay of diagnosis and increasing of complications. Therefore, investigating the proliferation of Brucella in host cells is important to understand the pathogenesis of the disease. Dihydroartemisinin (DHA), a semi-synthetic derivative of artemisinin, has been recommended by World Health Organization as an anti-malarial drug. However, there have been few studies regarding its effectiveness against bacteria. In the present study, it was revealed that B. suis vaccine strain 2 (S2) grew in BV2 cells without significant cytotoxicity, and less than 20 µM DHA had no inhibitory effects on BV2 cells. Furthermore, DHA reduced B. suis S2 growth in BV2 cells, and increased the percentage of apoptosis and the expression of cleaved caspase-3 in B. suis S2-infected cells. Collectively, the present data indicated that DHA induced the caspase-dependent apoptotic pathway to inhibit the intracellular B. suis S2 growth.