Scorpion Venom Interactions with the Immune System

Abstract

Scorpion envenomation (SE) is a common medical problem in many countries; it is an important cause of morbidity and mortality, especially among children. In certain cases scorpion stings lead to multiorgan failure that may be fatal; the manifestations include acute respiratory distress syndrome and systemic inflammatory response syndrome. Neurotoxins are the most active components of the scorpion venom responsible for the toxic effects induced after SE. They induce a massive release of neurotransmitters during stimulation of sympathetic and parasympathetic of the autonomic nervous system. The pathophysiological disturbances caused by scorpion venom are not exclusively assigned to the released neurotransmitters. The activation and release of inflammatory mediators (cytokines, kinins, eicosanoids, reactive oxygen species, and nitric oxide) may also play an important role in the pathophysiology of envenomation after stings and may be responsible for some of the inflammatory manifestations and organ failure. The massive release of these mediators from injured and activated cells promotes the inflammatory response and may be responsible for its exacerbation and its maintenance. The present chapter focuses on the role of inflammatory mediators and on elucidation of the potential mechanisms by which the immune system affects the pathophysiology following SE. Understanding of involved inflammatory cascade in scorpion envenoming syndromes may have future therapeutic and diagnostic benefits.

Cytotoxic activity of Androctonus australis hector venom and its toxic fractions on human lung cancer cell line

“…Androctonus australis hector (Aah) scorpion is the most endemic species from North Africa belonging to Buthidae family [ 19 ]. Typical manifestations of Aah scorpion envenomation are cardiac dysfunction, systemic inflammatory response syndrome, pulmonary edema and respiratory failure [ 20 ]. Three fractions were isolated from this venom by gel filtration.…”

Scorpion Venom: Detriments and Benefits

“…Several scorpion toxins can modulate the immune system [158]. Indeed, the contribution of released inflammatory mediators (e.g., cytokines, eicosanoids, and reactive oxygen species) and activation of the complement system is well explored in the envenoming pathophysiology following scorpion stings [57,158,159].…”

Neurological and Systemic Manifestations of Severe Scorpion Envenomation

“…Two groups of these substances stand out, those that trigger and sustain inflammation such as interleukin (IL)-1β, IL-6, IL-8, and tumor necrosis factor (TNF)-alpha, while others oppose, counterbalancing the action of the previous ones such as IL-4 and IL-10. The balance of pro-and anti-inflammatory responses will depend on the clinical manifestations of the poisoning [4,[6][7][8][9].…”

“…Additionally, the toxin stimulates the release of nitric oxide, endothelin, and neuropeptide Y. It activates the coagulation and complement systems, resulting in a vicious circle of inflammation, micro-thrombosis, and neuronal damage [4,[6][7][8][9] (Figure 2).…”

“…The antivenom dose depends on the severity of the clinical picture and the amount of inoculated venom (generally unknown). If we take into account 30 to 50 LD50 of venom, based on the type of antivenom, generally 5 mL in mild to 20 mL or more in severe cases is required [9].…”