Evaluation of bristles extract effects of Premolis semirufa, etiologic agent of pararamose, on human chondrocytes

Abstract

Present in the Amazon region, the caterpillar of Premolis semirufa (Pararama) is the parasite of the rubber Hevea genus. The contact with the bristles, in most cases, causes an intense itching sensation, followed by symptoms of the acute inflammation such as pain, heat and redness, which last for three to seven days. On the other hand, a chronic inflammatory reaction frequently occurs in individuals after multiple accidents, which is characterized by articular synovial 'membrane thickening. These deformities are common to chronic synovitis mono or oligoarticulares, such as rheumatoid I arthritis and osteoarthritis, chronic degenerative diseases of the joint, which result in the degradation of articular cartilage, inflammation of the synovium (synovitis) and changes in subchondral bone, with involvement of production of many cytokines, inflammatory mediators and growth factors for the articular tissues. So far, there is no effective treatment for the accidents with pararama. Studies about the pararamose are scarce, not only regarding the characterization of the toxic substances released by the caterpillar bristles, but also on the molecular mechanisms involved in its pathogenesis. Thus, the aim of the present study is to evaluate the possible toxic effect of the Premolis semirufa's bristles extract on human chondrocytes by means of analysis of the viability and morphological changes of the cells, production of cytokines, such as IL-1, IL-6, IL-7, IL-17 and TNF-α and of chemokines, such as IL-8 and CCL5, NO dosage, expression of matrix metalloproteinases and angiogenic factors, both from culture supernatants as from nuclear and cytoplasmic extracts of cells. Moreover, it is intended to assess the production of components of the Complement System and the expression of TLRs by these cells. (AU)