IL6 and systemic lupus erythematosus: Naja naja atra snake venom and its toxin neurotoxin-Nna has been shown to decrease IL-1β and TNF-α levels in the kidney and the serum of rats, respectively [86,87]; in addition, N. n. atra venom can inhibit IL-6 and TNF-α production in systemic lupus erythematosus in mice [88].