Abstract

Rheumatoid arthritis (RA) patients suffer from the effects of acute and chronic inflammation, and it can be deteriorated by the production of endothelin-1, which is a pro-inflammatory molecule and participates in the pathogenesis of RA. Bee venom (BV) with low doses plays an anti-inflammatory role in the treatment of RA. Besides, nano-emulsions (NEs) increase topical drug delivery and its effectiveness. This project was designed to explore the effects of nano-emulsions containing bee venom (Top-NEs) on the serum level of endothelin-1 in the rats of the collagen-induced RA (CIA) model. After induction of CIA in Wistar rats and grouping, the serum levels of endothelin-1 were measured in four steps. In healthy rats on day 0, in CIA model before, middle, and at the end of treatment on days 7, 14, and 21, respectively. The results demonstrated that serum levels of endothelin-1 had significantly increased in CIA rats before treatment, and they were more in the middle and the end of treatment about blank and negative control groups. However, they had significantly decreased in the Top-NEs groups in the middle and the end of treatment. Topical NEs containing BV can ameliorate the serum level of endothelin-1 in the CIA model; in addition, they can pass BV through the skin. Also, it appears that endothelin-1 can be considered as the main target for the treatment of RA. © 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.