Influence of envenomation timing on peripheral immune and oxidative responses in experimental scorpion envenomation

Scorpion envenomation poses a significant health threat in endemic regions, eliciting complex immune responses in affected individuals. Recent research suggests that the timing of envenomation - whether it occurs during the day or night - may influence the host inflammatory response and subsequent organ damage. This study investigates the impact of envenomation timing on host inflammatory and oxidative responses using an experimental scorpion envenomation model.

Mice were divided into two groups, corresponding to their resting phase (day) and activity phase (night), and were monitored for twenty-four hours post-envenomation. We analyzed systemic inflammatory markers, hormonal changes within the hypothalamic-pituitary-adrenal (HPA) axis, and assessed liver toxicity.

Our findings reveal that the release of the myeloperoxidase enzyme, along with the pro-inflammatory cytokines IL-6 and IL-17, varied significantly based on the timing of envenomation. Notably, envenomation occurring during the nighttime resulted in elevated levels of these mediators. We also observed a pronounced imbalance in oxidative stress, characterized by a higher presence of prooxidant species during the daytime and enhanced antioxidant activities during the nighttime. This diurnal variation highlights the dynamic nature of the inflammatory and oxidative processes. Importantly, our analysis points to the probable involvement of corticosterone, the final effector of the HPA axis, in modulating these variations in the inflammatory response. By influencing both the intensity of the immune response and the degree of oxidative stress, corticosterone appears to play a pivotal role in the overall pathophysiology of scorpion envenomation.

This study provides valuable insights into how the timing of scorpion envenomation influences inflammatory responses and organ-specific toxicity, offering potential implications for the treatment and management of envenomation cases.