Bothrops jararaca venom and renal failure: molecular bases of toxicity on mesangial cells and murine renal tissue, the synergistic effect of plasma protein degradation products, and the role of cathepsins

• Grant number: 23/17619-5
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: April 01, 2024
• End date: May 31, 2026
• Field of knowledge: Biological Sciences - Biochemistry - Chemistry of Macromolecules
• Principal Investigator: Solange Maria de Toledo Serrano
• Grantee: Jorge da Cruz Moschem
• Host Institution: Instituto Butantan. Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil
• Associated research grant: 13/07467-1 - CeTICS - Center of Toxins, Immune-Response and Cell Signaling, AP.CEPID
• Associated scholarship(s): 24/22646-4 - Mapping of spatial distribution of tissue protease activity in mice injected with Bothrops jararaca snake venom by mass spectrometry and multispectral microscopy., BE.EP.DD

Abstract

Bothrops snake venoms are composed of several families of protein toxins, in addition to bioactive peptides. In Brazil, Bothrops snakes are responsible for more than 90% of cases of accidents, in which the clinical symptoms observed after the bite include local and systemic effects, with the presence of edema, hemorrhage, necrosis, severe coagulopathy, and kidney failure. Therefore, to better understand the mechanisms of venom toxicity, especially in the kidneys, the general objective of the present project is to analyze the effects of Bothrops jararaca venom on renal tissue and mesangial cells derived from the murine renal glomerulus (SV40 MES 13 cells). Furthermore, we intend to evaluate the possible synergistic effect between the venom toxins and the degradation products of plasma proteins by the venom proteolytic enzymes, as well as the participation of endogenous cysteine proteases (cathepsins) in the renal pathological conditions triggered upon envenomation. To this end, the following specific objectives are proposed: I. To evaluate cell viability after exposure to native venom; II. In case of decreased cell viability, to characterize the type of cell death induced by the native venom; III. To characterize the morphological changes of kidney cells exposed to native venom, using light microscopy and immunofluorescence; IV. To analyze the proteomic/N-terminomic and peptidomic profiles of the secretome of cells incubated with native venom of adult snakes and newborn, by mass spectrometry; V. To analyze the proteomic/N-terminomic and peptidomic profiles of the secretome of cells incubated with the native venom in the presence of peptides generated from the incubation of plasma with the venom, by mass spectrometry (proteins and peptides); VI. To analyze the proteomic/N-terminomic and peptidomic profiles of cells in culture and kidney tissue from mouse exposed to the native venom of B. jararaca together with an inhibitor of cathepsin-type cysteine proteases, by mass spectrometry. By exploring the effects of a venom on kidney tissue and cells, using quantitative molecular methods combined with immunostaining, this study will contribute to the understanding of the renal tissue response to a complex mixture of toxins (venom), mapping the signaling pathways involved in this response. Furthermore, the poorly studied aspect of the synergistic effect of plasma protein degradation products generated by a venom rich in proteases, as is the case of B. jararaca, may shed light on the concerted action of toxins in the generation of local and systemic pathology of envenomation. (AU)