Protective effects of mesenchymal stromal cell-derived secretome on dermonecrosis induced in rabbits by Loxosceles intermedia spider venom

• Published in: Journal of Venomous Animals and Toxins including Tropical Diseases
• Main Authors: Gabriela Marques Rodrigues, Mara Elvira de Almeida, Sóstenes Apolo Correia Marcelino, Paula Bretas Ullmann Fernandes, Jessica Oliveira Pereira da Cruz, Françoise Louanne Araújo, Raquel da Silva Ferreira, Ana Flávia Machado Botelho, Francisco Javier Bedoya, Gladys Margot Cahuana, Ana Belén Hitos, Bernat Soria, Fernanda Costal-Oliveira, Clara Guerra Duarte, Juan R. Tejedo, Carlos Chávez-Olórtegui, Marília Martins Melo
• Format: Article in Journal/Newspaper
• Language: English
• Published: SciELO 2024
• Subjects: Loxoscelism; Loxosceles intermedia; Regenerative therapy; Secretome; Arctic medicine. Tropical medicine; RC955-962; Toxicology. Poisons; RA1190-1270; Zoology; QL1-991; Arctic
• Online Access: https://doi.org/10.1590/1678-9199-jvatitd-2024-0004; https://doaj.org/article/f80704d0eb384d8389ae0111396b9270

Abstract Background: Loxoscelism refers to a set of clinical manifestations caused by the bite of spiders from the Loxosceles genus. The classic clinical symptoms are characterized by an intense inflammatory reaction at the bite site followed by local necrosis and can be classified as cutaneous loxoscelism. This cutaneous form presents difficult healing, and the proposed treatments are not specific or effective. This study aimed to evaluate the protective effect of mesenchymal stromal cells-derived secretome on dermonecrosis induced by Loxosceles intermedia spider venom in rabbits. Methods: Sixteen rabbits were distributed into four groups (n = 4). Except for group 1 (G1), which received only PBS, the other three groups (G2, G3, and G4) were initially challenged with 10 μg of L. intermedia venom, diluted in 100 μL of NaCl 0.9%, by intradermic injection in the interscapular region. Thirty minutes after the challenge all groups were treated with secretome, except for group 2. Group 1 (G1-control group) received intradermal injection (ID) of 60 μg of secretome in 0.15 M PBS; Group 2 (G2) received 0.9% NaCl via ID; Group 3 (G3) received 60 μg of secretome, via ID and Group 4 (G4), received 60 μg of secretome by intravenous route. Rabbits were evaluated daily and after 15 days were euthanized, necropsied and skin samples around the necrotic lesions were collected for histological analysis. Results: Rabbits of G1 did not present edema, erythema, hemorrhagic halo, or necrosis. In animals from G2, G3, and G4, edema appeared after 6h. However, minor edema was observed in the animals of G2 and G3. Hemorrhagic halo was observed in animals, six hours and three days after, on G2, G3, and G4. Macroscopically, in G4, only one animal out of four had a lesion that evolved into a dermonecrotic wound. No changes were observed in the skin of the animals of G1, by microscopic evaluation. All animals challenged with L. intermedia venom showed similar alterations, such as necrosis and heterophilic infiltration. However, animals from ...