Apis mellifera syriaca Venom Modulates Splenic Cytokines Levels in BALB/c Mice.

Bee venoms are well-known for their important biological activities. More specifically, the venom of Apis mellifera syriaca was shown to exhibit various biological effects, including antimicrobial effects. It is suggested that the anti-microbial effect of venom could be accompanied by an immunomodulatory response in the host favoring anti-inflammatory responses. Thus, in this work, we investigated, for the first time, the immunomodulatory effects of A. mellifera syriaca venom in mice. Firstly, it was found that this venom exhibited mild toxicity in BALB/c mice after intraperitoneal injection with an LD50 of 3.8 mg/kg. We then investigated its immunomodulatory effects by evaluating the splenic levels of both pro- and anti-inflammatory cytokines in mice by ELISA. Interestingly, at 1 mg/kg, A. mellifera syriaca venom induced a decrease in IFN-γ, TNF-α, IL-4, and IL-10 at 24h postinjection. At a higher dose (3 mg/kg), an increase in IFN-γ and IL-4 levels was observed, while the levels of TNF-α and IL-10 remained low compared to the control. Altogether, these preliminary data suggest that A. mellifera syriaca venom exhibits anti-inflammatory effects at a sublethal dose (1 mg/kg), while at a higher dose (3 mg/kg), it induces inflammatory effects.